WorldWideScience

Sample records for borrelia outer surface

  1. Analysis of the lipidated recombinant outer surface protein A from Borrelia burgdorferi by mass spectrometry

    NARCIS (Netherlands)

    Bouchon, B.; Klein, Michele; Bischoff, Rainer; Van Dorsselaer, A.; Roitsch, C.

    1997-01-01

    The outer surface protein A, OspA, from the spirochete Borrelia burgdorferi is a lipoprotein of 25 kDa. The recombinant OspA (rOspA) expressed in Escherichia coli has been purified and analyzed by electrospray mass spectrometry (ESMS). A heterogenous spectrum gave a measured mass of 28,462 +/- 9 Da

  2. Rapid outer-surface protein C DNA tattoo vaccination protects against Borrelia afzelii infection.

    Science.gov (United States)

    Wagemakers, A; Mason, L M K; Oei, A; de Wever, B; van der Poll, T; Bins, A D; Hovius, J W R

    2014-12-01

    Borrelia afzelii is the predominant Borrelia species causing Lyme borreliosis in Europe. Currently there is no human vaccine against Lyme borreliosis, and most research focuses on recombinant protein vaccines against Borrelia burgdorferi sensu stricto. DNA tattooing is a novel vaccination method that can be applied in a rapid vaccination schedule. We vaccinated C3H/HeN mice with B. afzelii strain PKo OspC (outer-surface protein C) using a codon-optimized DNA vaccine tattoo and compared this with recombinant protein vaccination in a 0-2-4 week vaccination schedule. We also assessed protection by DNA tattoo in a 0-3-6 day schedule. DNA tattoo and recombinant OspC vaccination induced comparable total IgG responses, with a lower IgG1/IgG2a ratio after DNA tattoo. Two weeks after syringe-challenge with 5 × 10(5) B. afzelii spirochetes most vaccinated mice had negative B. afzelii tissue DNA loads and all were culture negative. Furthermore, DNA tattoo vaccination in a 0-3-6 day regimen also resulted in negative Borrelia loads and cultures after challenge. To conclude, DNA vaccination by tattoo was fully protective against B. afzelii challenge in mice in a rapid vaccination protocol, and induces a favorable humoral immunity compared to recombinant protein vaccination. Rapid DNA tattoo is a promising vaccination strategy against spirochetes.

  3. Outer surface protein B is critical for Borrelia burgdorferi adherence and survival within Ixodes ticks.

    Directory of Open Access Journals (Sweden)

    Girish Neelakanta

    2007-03-01

    Full Text Available Survival of Borrelia burgdorferi in ticks and mammals is facilitated, at least in part, by the selective expression of lipoproteins. Outer surface protein (Osp A participates in spirochete adherence to the tick gut. As ospB is expressed on a bicistronic operon with ospA, we have now investigated the role of OspB by generating an OspB-deficient B. burgdorferi and examining its phenotype throughout the spirochete life cycle. Similar to wild-type isolates, the OspB-deficient B. burgdorferi were able to readily infect and persist in mice. OspB-deficient B. burgdorferi were capable of migrating to the feeding ticks but had an impaired ability to adhere to the tick gut and survive within the vector. Furthermore, the OspB-deficient B. burgdorferi bound poorly to tick gut extracts. The complementation of the OspB-deficient spirochete in trans, with a wild-type copy of ospB gene, restored its ability to bind tick gut. Taken together, these data suggest that OspB has an important role within Ixodes scapularis and that B. burgdorferi relies upon multiple genes to efficiently persist in ticks.

  4. Selective association of outer surface lipoproteins with the lipid rafts of Borrelia burgdorferi.

    Science.gov (United States)

    Toledo, Alvaro; Crowley, Jameson T; Coleman, James L; LaRocca, Timothy J; Chiantia, Salvatore; London, Erwin; Benach, Jorge L

    2014-03-11

    Borrelia burgdorferi contains unique cholesterol-glycolipid-rich lipid rafts that are associated with lipoproteins. These complexes suggest the existence of macromolecular structures that have not been reported for prokaryotes. Outer surface lipoproteins OspA, OspB, and OspC were studied for their participation in the formation of lipid rafts. Single-gene deletion mutants with deletions of ospA, ospB, and ospC and a spontaneous gene mutant, strain B313, which does not express OspA and OspB, were used to establish their structural roles in the lipid rafts. All mutant strains used in this study produced detergent-resistant membranes, a common characteristic of lipid rafts, and had similar lipid and protein slot blot profiles. Lipoproteins OspA and OspB but not OspC were shown to be associated with lipid rafts by transmission electron microscopy. When the ability to form lipid rafts in live B. burgdorferi spirochetes was measured by fluorescence resonance energy transfer (FRET), strain B313 showed a statistically significant lower level of segregation into ordered and disordered membrane domains than did the wild-type and the other single-deletion mutants. The transformation of a B313 strain with a shuttle plasmid containing ospA restored the phenotype shared by the wild type and the single-deletion mutants, demonstrating that OspA and OspB have redundant functions. In contrast, a transformed B313 overexpressing OspC neither rescued the FRET nor colocalized with the lipid rafts. Because these lipoproteins are expressed at different stages of the life cycle of B. burgdorferi, their selective association is likely to have an important role in the structure of prokaryotic lipid rafts and in the organism's adaptation to changing environments. IMPORTANCE Lipid rafts are cholesterol-rich clusters within the membranes of cells. Lipid rafts contain proteins that have functions in sensing the cell environment and transmitting signals. Although selective proteins are present in

  5. Rapid outer-surface protein C DNA tattoo vaccination protects against Borrelia afzelii infection

    NARCIS (Netherlands)

    Wagemakers, A.; Mason, L. M. K.; Oei, A.; de Wever, B.; van der Poll, T.; Bins, A. D.; Hovius, J. W. R.

    2014-01-01

    Borrelia afzelii is the predominant Borrelia species causing Lyme borreliosis in Europe. Currently there is no human vaccine against Lyme borreliosis, and most research focuses on recombinant protein vaccines against Borrelia burgdorferi sensu stricto. DNA tattooing is a novel vaccination method

  6. Borrelia burgdorferi outer surface protein C (OspC) binds complement component C4b and confers bloodstream survival.

    Science.gov (United States)

    Caine, Jennifer A; Lin, Yi-Pin; Kessler, Julie R; Sato, Hiromi; Leong, John M; Coburn, Jenifer

    2017-12-01

    Borrelia burgdorferi (Bb) is the causative agent of Lyme disease in the United States, a disease that can result in carditis, and chronic and debilitating arthritis and/or neurologic symptoms if left untreated. Bb survives in the midgut of the Ixodes scapularis tick, or within tissues of immunocompetent hosts. In the early stages of infection, the bacteria are present in the bloodstream where they must resist clearance by the innate immune system of the host. We have found a novel role for outer surface protein C (OspC) from B. burgdorferi and B. garinii in interactions with the complement component C4b and bloodstream survival in vivo. Our data show that OspC inhibits the classical and lectin complement pathways and competes with complement protein C2 for C4b binding. Resistance to complement is important for maintenance of the lifecycle of Bb, enabling survival of the pathogen within the host as well as in the midgut of a feeding tick when ospC expression is induced. © 2017 John Wiley & Sons Ltd.

  7. Use of T7 RNA polymerase to direct expression of outer Surface Protein A (OspA) from the Lyme disease Spirochete, Borrelia burgdorferi

    Science.gov (United States)

    Dunn, John J.; Lade, Barbara N.

    1991-01-01

    The OspA gene from a North American strain of the Lyme disease Spirochete, Borrelia burgdorferi, was cloned under the control of transciption and translation signals from bacteriophage T7. Full-length OspA protein, a 273 amino acid (31kD) lipoprotein, is expressed poorly in Escherichia coli and is associated with the insoluble membrane fraction. In contrast, a truncated form of OspA lacking the amino-terminal signal sequence which normally would direct localization of the protein to the outer membrane is expressed at very high levels (less than or equal to 100 mg/liter) and is soluble. The truncated protein was purified to homogeneity and is being tested to see if it will be useful as an immunogen in a vaccine against Lyme disease. Circular dichroism and fluorescence spectroscopy was used to characterize the secondary structure and study conformational changes in the protein. Studies underway with other surface proteins from B burgdorferi and a related spirochete, B. hermsii, which causes relapsing fever, leads us to conclude that a strategy similar to that used to express the truncated OspA can provide a facile method for producing variations of Borrelia lipoproteins which are highly expressed in E. coli and soluble without exposure to detergents.

  8. Competitive advantage of Borrelia burgdorferi with outer surface protein BBA03 during tick-mediated infection of the mammalian host.

    Science.gov (United States)

    Bestor, Aaron; Rego, Ryan O M; Tilly, Kit; Rosa, Patricia A

    2012-10-01

    Linear plasmid lp54 is one of the most highly conserved and differentially expressed elements of the segmented genome of the Lyme disease spirochete Borrelia burgdorferi. We previously reported that deletion of a 4.1-kb region of lp54 (bba01 to bba07 [bba01-bba07]) led to a slight attenuation of tick-transmitted infection in mice following challenge with a large number of infected ticks. In the current study, we reduced the number of ticks in the challenge to more closely mimic the natural dose and found a profound defect in tick-transmitted infection of the bba01-bba07 mutant relative to wild-type B. burgdorferi. We next focused on deletion of bba03 as the most likely cause of this mutant phenotype, as previous studies have shown that expression of bba03 is increased by culture conditions that simulate tick feeding. Consistent with this hypothesis, we demonstrated increased expression of bba03 by spirochetes in fed relative to unfed ticks. We also observed that a bba03 deletion mutant, although fully competent by itself, did not efficiently infect mice when transmitted by ticks that were simultaneously coinfected with wild-type B. burgdorferi. These results suggest that BBA03 provides a competitive advantage to spirochetes carrying this protein during tick transmission to a mammalian host in the natural infectious cycle.

  9. Stable Transmission of Borrelia burgdorferi Sensu Stricto on the Outer Banks of North Carolina.

    Science.gov (United States)

    Levine, J F; Apperson, C S; Levin, M; Kelly, T R; Kakumanu, M L; Ponnusamy, L; Sutton, H; Salger, S A; Caldwell, J M; Szempruch, A J

    2017-08-01

    The spirochaete (Borrelia burgdorferi) associated with Lyme disease was detected in questing ticks and rodents during a period of 18 years, 1991-2009, at five locations on the Outer Banks of North Carolina. The black-legged tick (Ixodes scapularis) was collected at varied intervals between 1991 and 2009 and examined for B. burgdorferi. The white-footed mouse (Peromyscus leucopus), house mouse (Mus musculus) marsh rice rat (Oryzomys palustris), marsh rabbit (Sylvilagus palustris), eastern cottontail (Sylvilagus floridanus) and six-lined racerunner (Cnemidophorus sexlineatus) were live-trapped, and their tissues cultured to isolate spirochaetes. Borrelia burgdorferi isolates were obtained from questing adult I. scapularis and engorged I. scapularis removed from P. leucopus, O. palustris and S. floridanus. The prevalence of B. burgdorferi infection was variable at different times and sites ranging from 7 to 14% of examined questing I. scapularis. Mitochondrial (16S) rRNA gene phylogenetic analysis from 65 adult I. scapularis identified 12 haplotypes in two major clades. Nine haplotypes were associated with northern/Midwestern I. scapularis populations and three with southern I. scapularis populations. Sixteen isolates obtained from tick hosts in 2005 were confirmed to be B. burgdorferi by amplifying and sequencing of 16S rRNA and 5S-23S intergenic spacer fragments. The sequences had 98-99% identity to B. burgdorferi sensu stricto strains B31, JD1 and M11p. Taken together, these studies indicate that B. burgdorferi sensu stricto is endemic in questing I. scapularis and mammalian tick hosts on the Outer Banks of North Carolina. © 2016 Blackwell Verlag GmbH.

  10. Coordinated Expression of Borrelia burgdorferi Complement Regulator-Acquiring Surface Proteins during the Lyme Disease Spirochete's Mammal-Tick Infection Cycle▿

    OpenAIRE

    Bykowski, Tomasz; Woodman, Michael E.; Cooley, Anne E.; Brissette, Catherine A.; Brade, Volker; Wallich, Reinhard; Kraiczy, Peter; Stevenson, Brian

    2007-01-01

    The Lyme disease spirochete, Borrelia burgdorferi, is largely resistant to being killed by its hosts’ alternative complement activation pathway. One possible resistance mechanism of these bacteria is to coat their surfaces with host complement regulators, such as factor H. Five different B. burgdorferi outer surface proteins having affinities for factor H have been identified: complement regulator-acquiring surface protein 1 (BbCRASP-1), encoded by cspA; BbCRASP-2, encoded by cspZ; and three ...

  11. Transcriptional regulation of the Borrelia burgdorferi antigenically variable VlsE surface protein.

    Science.gov (United States)

    Bykowski, Tomasz; Babb, Kelly; von Lackum, Kate; Riley, Sean P; Norris, Steven J; Stevenson, Brian

    2006-07-01

    The Lyme disease agent Borrelia burgdorferi can persistently infect humans and other animals despite host active immune responses. This is facilitated, in part, by the vls locus, a complex system consisting of the vlsE expression site and an adjacent set of 11 to 15 silent vls cassettes. Segments of nonexpressed cassettes recombine with the vlsE region during infection of mammalian hosts, resulting in combinatorial antigenic variation of the VlsE outer surface protein. We now demonstrate that synthesis of VlsE is regulated during the natural mammal-tick infectious cycle, being activated in mammals but repressed during tick colonization. Examination of cultured B. burgdorferi cells indicated that the spirochete controls vlsE transcription levels in response to environmental cues. Analysis of PvlsE::gfp fusions in B. burgdorferi indicated that VlsE production is controlled at the level of transcriptional initiation, and regions of 5' DNA involved in the regulation were identified. Electrophoretic mobility shift assays detected qualitative and quantitative changes in patterns of protein-DNA complexes formed between the vlsE promoter and cytoplasmic proteins, suggesting the involvement of DNA-binding proteins in the regulation of vlsE, with at least one protein acting as a transcriptional activator.

  12. BB0347, from the lyme disease spirochete Borrelia burgdorferi, is surface exposed and interacts with the CS1 heparin-binding domain of human fibronectin.

    Directory of Open Access Journals (Sweden)

    Robert A Gaultney

    Full Text Available The causative agent of Lyme disease, Borrelia burgdorferi, codes for several known fibronectin-binding proteins. Fibronectin a common the target of diverse bacterial pathogens, and has been shown to be essential in allowing for the development of certain disease states. Another borrelial protein, BB0347, has sequence similarity with these other known fibronectin-binding proteins, and may be important in Lyme disease pathogenesis. Herein, we perform an initial characterization of BB0347 via the use of molecular and biochemical techniques. We found that BB0347 is expressed, produced, and presented on the outer surface of intact B. burgdorferi. We also demonstrate that BB0347 has the potential to be important in Lyme disease progression, and have begun to characterize the nature of the interaction between human fibronectin and this bacterial protein. Further work is needed to define the role of this protein in the borrelial infection process.

  13. Ultrasonic examination of defects close to the outer surface

    International Nuclear Information System (INIS)

    Benoist, P.; Serre, M.; Champigny, F.

    1986-11-01

    During the examination of a pressurized water reactor vessel with an in Service Inspection Machine (MIS), various welds are scanned with immersion ultrasonic focused transducers from the inside of the vessel. Defects close to the outer surface are sometimes detected, and sizing with the successive 6 dB drop method leads to oversize some indications; this is caused by various reflections on the outer wall; the corner echo is of particular importance here. CEA and EDF have started an experimental program in order to study the response of volumetric and planar defects located near the outer surface. We present here the first results obtained with artificial defects. 2 refs

  14. Stability of marginally outer trapped surfaces and symmetries

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, Alberto; Mars, Marc, E-mail: acf@usal.e, E-mail: marc@usal.e [Facultad de Ciencias, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain)

    2009-09-07

    We study the properties of stable, strictly stable and locally outermost marginally outer trapped surfaces in spacelike hypersurfaces of spacetimes possessing certain symmetries such as isometries, homotheties and conformal Killings. We first obtain results for general diffeomorphisms in terms of the so-called metric deformation tensor and then particularize to different types of symmetries. In particular, we find restrictions at the surfaces on the vector field generating the symmetry. Some consequences are discussed. As an application, we present a result on non-existence of stable marginally outer trapped surfaces in slices of FLRW.

  15. Exposed and hidden lectin-binding epitopes at the surface of Borrelia burgdorferi

    Czech Academy of Sciences Publication Activity Database

    Stoitsova, S. R.; Grubhoffer, Libor; Nebesářová, Jana

    2003-01-01

    Roč. 48, č. 5 (2003), s. 654-658 ISSN 0015-5632 R&D Projects: GA AV ČR IAA6022001 Grant - others:National Research Council at the Ministry of Education and Science(BG) K-709/97 Institutional research plan: CEZ:AV0Z6022909 Keywords : Borrelia burgdorferi * lectin-binding epitopes Subject RIV: EE - Microbiology, Virology Impact factor: 0.857, year: 2003

  16. Borrelia-induced cytokine production is mediated by spleen tyrosine kinase (Syk) but is Dectin-1 and Dectin-2 independent

    NARCIS (Netherlands)

    Oosting, M.; Buffen, K.; Cheng, S.C.; Verschueren, I.C.; Koentgen, F.; Veerdonk, F.L. van de; Netea, M.G.; Joosten, L.A.B.

    2015-01-01

    Although it is known that Borrelia species express sugar-like structures on their outer surface, not much is known about the role of these structures in immune recognition by host cells. Fungi, like Candida albicans, are mainly recognized by C-type lectin receptors, in specific Dectin-1 and

  17. Fluid flow near the surface of earth's outer core

    Science.gov (United States)

    Bloxham, Jeremy; Jackson, Andrew

    1991-01-01

    This review examines the recent attempts at extracting information on the pattern of fluid flow near the surface of the outer core from the geomagnetic secular variation. Maps of the fluid flow at the core surface are important as they may provide some insight into the process of the geodynamo and may place useful constraints on geodynamo models. In contrast to the case of mantle convection, only very small lateral variations in core density are necessary to drive the flow; these density variations are, by several orders of magnitude, too small to be imaged seismically; therefore, the geomagnetic secular variation is utilized to infer the flow. As substantial differences exist between maps developed by different researchers, the possible underlying reasons for these differences are examined with particular attention given to the inherent problems of nonuniqueness.

  18. Inverse analysis of inner surface temperature history from outer surface temperature measurement of a pipe

    International Nuclear Information System (INIS)

    Kubo, S; Ioka, S; Onchi, S; Matsumoto, Y

    2010-01-01

    When slug flow runs through a pipe, nonuniform and time-varying thermal stresses develop and there is a possibility that thermal fatigue occurs. Therefore it is necessary to know the temperature distributions and the stress distributions in the pipe for the integrity assessment of the pipe. It is, however, difficult to measure the inner surface temperature directly. Therefore establishment of the estimation method of the temperature history on inner surface of pipe is needed. As a basic study on the estimation method of the temperature history on the inner surface of a pipe with slug flow, this paper presents an estimation method of the temperature on the inner surface of a plate from the temperature on the outer surface. The relationship between the temperature history on the outer surface and the inner surface is obtained analytically. Using the results of the mathematical analysis, the inverse analysis method of the inner surface temperature history estimation from the outer surface temperature history is proposed. It is found that the inner surface temperature history can be estimated from the outer surface temperature history by applying the inverse analysis method, even when it is expressed by the multiple frequency components.

  19. Whole-Genome Sequences of Borrelia bissettii Borrelia valaisiana and Borrelia spielmanii

    Energy Technology Data Exchange (ETDEWEB)

    Schutzer S. E.; Dunn J.; Fraser-Liggett C. M.; Qiu W.-G.; Kraiczy P.; Mongodin E. F.; Luft B. J.; Casjens S. R.

    2012-01-01

    It has been known for decades that human Lyme disease is caused by the three spirochete species Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. Recently, Borrelia valaisiana, Borrelia spielmanii, and Borrelia bissettii have been associated with Lyme disease. We report the complete genome sequences of B. valaisiana VS116, B. spielmanii A14S, and B. bissettii DN127.

  20. Study on residual stress across the pipes' thickness using outer surface rapid heating. Development of pipe outer surface irradiated laser stress improvement process (L-SIP)

    International Nuclear Information System (INIS)

    Ohta, Takahiro; Terasaki, Toshio

    2009-01-01

    The new process called L-SIP (outer surface irradiated Laser Stress Improvement Process) is developed to improve the tensile residual stress of the inner surface near the butt welded joints of pipes in the compression stress. The temperature gradient occurs in the thickness of pipes in heating the outer surface rapidly by laser beam. By the thermal expansion difference between the inner surface and the outer surface, the compression plastic strain generates near the outer surface and the tensile plastic strain generates near the inner surface of pipes. The compression stress occurs near the inner surface of pipes by the plastic deformation. In this paper, the theoretical equation which calculates residual stress distribution from the inherent strain distribution in the thickness of pipes is derived. And, the relation between the distribution of temperature and the residual stress in the thickness is examined for various pipes size. (1) By rapidly heating from the outer surface, the residual stress near the inner surface of the pipe is improved to the compression stress. (2) Pipes size hardly affects the distribution of the residual stress in the stainless steel pipes for piping (JISG3459). (3) The temperature rising area from the outside is smaller, the area of the compression residual stress near the inner surface becomes wider. (author)

  1. Fine tuning the ionic liquid-vacuum outer atomic surface using ion mixtures.

    Science.gov (United States)

    Villar-Garcia, Ignacio J; Fearn, Sarah; Ismail, Nur L; McIntosh, Alastair J S; Lovelock, Kevin R J

    2015-03-28

    Ionic liquid-vacuum outer atomic surfaces can be created that are remarkably different from the bulk composition. In this communication we demonstrate, using low-energy ion scattering (LEIS), that for ionic liquid mixtures the outer atomic surface shows significantly more atoms from anions with weaker cation-anion interactions (and vice versa).

  2. Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis.

    Science.gov (United States)

    Hennig, Anna; Bonfig, Katharina; Roitsch, Thomas; Warzecha, Heribert

    2007-11-01

    Bacterial lipoproteins play crucial roles in host-pathogen interactions and pathogenesis and are important targets for the immune system. A prominent example is the outer surface protein A (OspA) of Borrelia burgdorferi, which has been efficiently used as a vaccine for the prevention of Lyme disease. In a previous study, OspA could be produced in tobacco chloroplasts in a lipidated and immunogenic form. To further explore the potential of chloroplasts for the production of bacterial lipoproteins, the role of the N-terminal leader sequence was investigated. The amount of recombinant OspA could be increased up to ten-fold by the variation of the insertion site in the chloroplast genome. Analysis of OspA mutants revealed that replacement of the invariant cysteine residue as well as deletion of the leader sequence abolishes palmitolyation of OspA. Also, decoration of OspA with an N-terminal eukaryotic lipidation motif does not lead to palmitoylation in chloroplasts. Strikingly, the bacterial signal peptide of OspA efficiently targets the protein to thylakoids, and causes a mutant phenotype. Plants accumulating OspA at 10% total soluble protein could not grow without exogenously supplied sugars and rapidly died after transfer to soil under greenhouse conditions. The plants were found to be strongly affected in photosystem II, as revealed by the analyses of temporal and spatial dynamics of photosynthetic activity by chlorophyll fluorescence imaging. Thus, overexpression of OspA in chloroplasts is limited by its concentration-dependent interference with essential functions of chloroplastic membranes required for primary metabolism.

  3. Application of Nanotrap technology for high sensitivity measurement of urinary outer surface protein A carboxyl-terminus domain in early stage Lyme borreliosis.

    Science.gov (United States)

    Magni, Ruben; Espina, Benjamin H; Shah, Ketul; Lepene, Benjamin; Mayuga, Christine; Douglas, Temple A; Espina, Virginia; Rucker, Sally; Dunlap, Ross; Petricoin, Emanuel F Iii; Kilavos, Mary Frekko; Poretz, Donald M; Irwin, Gilbert R; Shor, Samuel M; Liotta, Lance A; Luchini, Alessandra

    2015-11-04

    Prompt antibiotic treatment of early stage Lyme borreliosis (LB) prevents progression to severe multisystem disease. There is a clinical need to improve the diagnostic specificity of early stage Lyme assays in the period prior to the mounting of a robust serology response. Using a novel analyte harvesting nanotechnology, Nanotrap particles, we evaluated urinary Borrelia Outer surface protein A (OspA) C-terminus peptide in early stage LB before and after treatment, and in patients suspected of late stage disseminated LB. We employed Nanotrap particles to concentrate urinary OspA and used a highly specific anti-OspA monoclonal antibody (mAb) as a detector of the C-terminus peptides. We mapped the mAb epitope to a narrow specific OspA C-terminal domain OspA236-239 conserved across infectious Borrelia species but with no homology to human proteins and no cross-reactivity with relevant viral and non-Borrelia bacterial proteins. 268 urine samples from patients being evaluated for all categories of LB were collected in a LB endemic area. The urinary OspA assay, blinded to outcome, utilized Nanotrap particle pre-processing, western blotting to evaluate the OspA molecular size, and OspA peptide competition for confirmation. OspA test characteristics: sensitivity 1.7 pg/mL (lowest limit of detection), % coefficient of variation (CV) = 8 %, dynamic range 1.7-30 pg/mL. Pre-treatment, 24/24 newly diagnosed patients with an erythema migrans (EM) rash were positive for urinary OspA while false positives for asymptomatic patients were 0/117 (Chi squared p antibiotic therapy, 10/10 were positive for urinary OspA. Urinary OspA of 8/8 patients switched from detectable to undetectable following symptom resolution post-treatment. Specificity of the urinary OspA test for the clinical symptoms was 40/40. Specificity of the urinary OspA antigen test for later serology outcome was 87.5 % (21 urinary OspA positive/24 serology positive, Chi squared p = 4.072e(-15)). 41 of 100 patients under

  4. Charged particle modification of surfaces in the outer solar system

    International Nuclear Information System (INIS)

    Johnson, R.E.

    1987-01-01

    Voyager reflectance spectra data have indicated clear leading/trailing differences in the albedo of the icy Galilean and Saturian satellites. For the Galilean satellites, these have been analyzed by Nelson, et al. and, more recently, by McEwen. They have described the longitudinal dependence of this data and attempted to interpret this in terms of plasma and meteorite modification of the surface. Primary attention has been paid to Europa at which the leading/trailing differences are the largest. This data was reanalyzed extracting the single grain albedo (w) and constructing the Espat-function, W = (1-w)/w from this. Because w is near unity, W is approximately 2(alpha)D where alpha is the absorption coefficient and D is the grain size. In doing so, a direct comparison to the longitudinal plasma bombardment flux was found for the first time. This occurs primarily in the UV and is probably due to an absorption associated with implanted S, as the UV band of Voyager overlaps the IUE data of Lane et al. The relative importance of grain size effects and implant impurity effects can now be studied

  5. New configuration for efficient and durable copper coating on the outer surface of a tube

    Directory of Open Access Journals (Sweden)

    Irfan Ahmad

    2017-03-01

    Full Text Available A well-adhered copper coating on stainless steel power coupler parts is required in superconducting radio frequency (SRF accelerators. Radio frequency power coupler parts are complex, tubelike stainless steel structures, which require copper coating on their outer and inner surfaces. Conventional copper electroplating sometimes produces films with inadequate adhesion strength for SRF applications. Electroplating also requires a thin nickel strike layer under the copper coating, whose magnetic properties can be detrimental to SRF applications. Coaxial energetic deposition (CED and sputtering methods have demonstrated efficient conformal coating on the inner surfaces of tubes but coating the outer surface of a tube is challenging because these coating methods are line of sight. When the substrate is off axis and the plasma source is on axis, only a small section of the substrate’s outer surface is exposed to the source cathode. The conventional approach is to rotate the tube to achieve uniformity across the outer surface. This method results in poor film thickness uniformity and wastes most of the source plasma. Alameda Applied Sciences Corporation (AASC has developed a novel configuration called hollow external cathode CED (HEC-CED to overcome these issues. HEC-CED produces a film with uniform thickness and efficiently uses all eroded source material. The Cu film deposited on the outside of a stainless steel tube using the new HEC-CED configuration survived a high pressure water rinse adhesion test. HEC-CED can be used to coat the outside of any cylindrical structure.

  6. Low prevalence of Borrelia bavariensis in Ixodes ricinus ticks in southeastern Austria.

    Science.gov (United States)

    Glatz, Martin; Muellegger, Robert R; Hizo-Teufel, Cecilia; Fingerle, Volker

    2014-10-01

    Borrelia bavariensis was recently described as a distinct genospecies among the B. burgdorferi sensu lato complex. The prevalence of B. bavariensis in Austria, a highly endemic area for tick-transmitted pathogens, is scarcely characterized. To investigate the prevalence of B. bavariensis in Ixodes ricinus ticks we reevaluated the results of a study conducted in 518 ticks from southeastern Austria collected in 2002 and 2003. The presence of B. burgdorferi s.l.-specific DNA in ticks was analyzed by a PCR for the outer surface protein A (ospA) gene. Borrelia species were differentiated by restriction fragment length polymorphism (RFLP) analysis, and samples positive for B. bavariensis were further analyzed by multilocus sequence analysis. Two of 133 (1.5%) B. burgdorferi s.l.-positive I. ricinus ticks were infected with B. bavariensis. Both specimens were coinfected with the OspA serotype 5 of B. garinii. Borrelia bavariensis is present; however, seem to be rare in I. ricinus ticks in southeastern Austria. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. ErpC, a member of the complement regulator-acquiring family of surface proteins from Borrelia burgdorferi, possesses an architecture previously unseen in this protein family

    International Nuclear Information System (INIS)

    Caesar, Joseph J. E.; Johnson, Steven; Kraiczy, Peter; Lea, Susan M.

    2013-01-01

    The structure of ErpC, a member of the complement regulator-acquiring surface protein family from B. burgdorferi, has been solved, providing insights into the strategies of complement evasion by this zoonotic bacterium and suggesting a common architecture for other members of this protein family. Borrelia burgdorferi is a spirochete responsible for Lyme disease, the most commonly occurring vector-borne disease in Europe and North America. The bacterium utilizes a set of proteins, termed complement regulator-acquiring surface proteins (CRASPs), to aid evasion of the human complement system by recruiting and presenting complement regulator factor H on its surface in a manner that mimics host cells. Presented here is the atomic resolution structure of a member of this protein family, ErpC. The structure provides new insights into the mechanism of recruitment of factor H and other factor H-related proteins by acting as a molecular mimic of host glycosaminoglycans. It also describes the architecture of other CRASP proteins belonging to the OspE/F-related paralogous protein family and suggests that they have evolved to bind specific complement proteins, aiding survival of the bacterium in different hosts

  8. Further structural insights into the binding of complement factor H by complement regulator-acquiring surface protein 1 (CspA) of Borrelia burgdorferi

    International Nuclear Information System (INIS)

    Caesar, Joseph J. E.; Wallich, Reinhard; Kraiczy, Peter; Zipfel, Peter F.; Lea, Susan M.

    2013-01-01

    B. burgdorferi binds complement factor H using a dimeric surface protein, CspA (BbCRASP-1). Presented here is a new structure of CspA that suggests that there is a degree of flexibility between subunits which may have implications for complement regulator binding. Borrelia burgdorferi has evolved many mechanisms of evading the different immune systems across its range of reservoir hosts, including the capture and presentation of host complement regulators factor H and factor H-like protein-1 (FHL-1). Acquisition is mediated by a family of complement regulator-acquiring surface proteins (CRASPs), of which the atomic structure of CspA (BbCRASP-1) is known and shows the formation of a homodimeric species which is required for binding. Mutagenesis studies have mapped a putative factor H binding site to a cleft between the two subunits. Presented here is a new atomic structure of CspA which shows a degree of flexibility between the subunits which may be critical for factor H scavenging by increasing access to the binding interface and allows the possibility that the assembly can clamp around the bound complement regulators

  9. Overexpression and surface localization of the Chlamydia trachomatis major outer membrane protein in Escherichia coli

    DEFF Research Database (Denmark)

    Koehler, JF; Birkelund, Svend; Stephens, RS

    1992-01-01

    The Chlamydia trachomatis major outer membrane protein (MOMP) is the quantitatively predominant surface protein which has important functional, structural and antigenic properties. We have cloned and overexpressed the MOMP in Escherichia coli. The MOMP is surface exposed in C. trachomatis....... The induction of MOMP expression had a rapidly lethal effect on the L2rMOMP E. coli clone. Although no genetic system exists for Chlamydia, development of a stable, inducible E. coli clone which overexpresses the chlamydial MOMP permits a study of the biological properties of the MOMP, including...

  10. An overlapping region between the two terminal folding units of the outer surface protein A (OspA) controls its folding behavior.

    Science.gov (United States)

    Makabe, Koki; Nakamura, Takashi; Dhar, Debanjan; Ikura, Teikichi; Koide, Shohei; Kuwajima, Kunihiro

    2018-04-27

    Although many naturally occurring proteins consist of multiple domains, most studies on protein folding to date deal with single-domain proteins or isolated domains of multi-domain proteins. Studies of multi-domain protein folding are required for further advancing our understanding of protein folding mechanisms. Borrelia outer surface protein A (OspA) is a β-rich two-domain protein, in which two globular domains are connected by a rigid and stable single-layer β-sheet. Thus, OspA is particularly suited as a model system for studying the interplays of domains in protein folding. Here, we studied the equilibria and kinetics of the urea-induced folding-unfolding reactions of OspA probed with tryptophan fluorescence and ultraviolet circular dichroism. Global analysis of the experimental data revealed compelling lines of evidence for accumulation of an on-pathway intermediate during kinetic refolding and for the identity between the kinetic intermediate and a previously described equilibrium unfolding intermediate. The results suggest that the intermediate has the fully native structure in the N-terminal domain and the single layer β-sheet, with the C-terminal domain still unfolded. The observation of the productive on-pathway folding intermediate clearly indicates substantial interactions between the two domains mediated by the single-layer β-sheet. We propose that a rigid and stable intervening region between two domains creates an overlap between two folding units and can energetically couple their folding reactions. Copyright © 2018. Published by Elsevier Ltd.

  11. Inverse estimation for temperatures of outer surface and geometry of inner surface of furnace with two layer walls

    International Nuclear Information System (INIS)

    Chen, C.-K.; Su, C.-R.

    2008-01-01

    This study provides an inverse analysis to estimate the boundary thermal behavior of a furnace with two layer walls. The unknown temperature distribution of the outer surface and the geometry of the inner surface were estimated from the temperatures of a small number of measured points within the furnace wall. The present approach rearranged the matrix forms of the governing differential equations and then combined the reversed matrix method, the linear least squares error method and the concept of virtual area to determine the unknown boundary conditions of the furnace system. The dimensionless temperature data obtained from the direct problem were used to simulate the temperature measurements. The influence of temperature measurement errors upon the precision of the estimated results was also investigated. The advantage of this approach is that the unknown condition can be directly solved by only one calculation process without initially guessed temperatures, and the iteration process of the traditional method can be avoided in the analysis of the heat transfer. Therefore, the calculation in this work is more rapid and exact than the traditional method. The result showed that the estimation error of the geometry increased with increasing distance between measured points and inner surface and in preset error, and with decreasing number of measured points. However, the geometry of the furnace inner surface could be successfully estimated by only the temperatures of a small number of measured points within and near the outer surface under reasonable preset error

  12. Finite element simulation of surface defects in the automobile door outer panel

    International Nuclear Information System (INIS)

    Fukumura, Masaru; Yamasaki, Yuji; Inage, Daisuke; Fujita, Takashi

    2004-01-01

    Recently, a sheet metal forming simulation has become an indispensable tool for developing a new model of an automobile part within a limited short period. In these days, the utilization of a springback calculation of the formed part has been increasing. However, only a few papers on the prediction of surface defects have been reported in spite of serious needs.In this paper, surface defects in the door outer panel, especially those around the door handle embossment, have been investigated. Applying an explicit solver to the forming simulation, and an implicit solver to the springback calculation, we have tried to evaluate surface defects in the panel. In order to improve the accuracy of the simulation, numerical tools have been modeled including the precise shape of the draw beads so that the draw bead effects on both the material flow and the restraint on the springback deformation have been considered. Compared with the actual panel shape, which shows apparent surface defects, the simulated result has closely predicted the above defects around the embossment.To demonstrate the applicability of our simulation, a few sensitivity analyses have been carried out, modifying forming conditions such as blank holder force. Each result has shown slight but distinctive differences in the cross section profile of the panel. As a result, it has been realized that the influence of each considered factor on surface defects is qualitatively consistent with our practical knowledge

  13. Difference in radiocarbon ages of carbonized material from the inner and outer surfaces of pottery from a wetland archaeological site.

    Science.gov (United States)

    Miyata, Yoshiki; Minami, Masayo; Onbe, Shin; Sakamoto, Minoru; Matsuzaki, Hiroyuki; Nakamura, Toshio; Imamura, Mineo

    2011-01-01

    AMS (Accelerator Mass Spectrometry) radiocarbon dates for eight potsherds from a single piece of pottery from a wetland archaeological site indicated that charred material from the inner pottery surfaces (5052 ± 12 BP; N = 5) is about 90 (14)C years older than that from the outer surfaces (4961 ± 22 BP; N = 7). We considered three possible causes of this difference: the old wood effect, reservoir effects, and diagenesis. We concluded that differences in the radiocarbon ages between materials from the inner and outer surfaces of the same pot were caused either by the freshwater reservoir effect or by diagenesis. Moreover, we found that the radiocarbon ages of carbonized material on outer surfaces (soot) of pottery from other wetland archaeological sites were the same as the ages of material on inner surfaces (charred food) of the same pot within error, suggesting absence of freshwater reservoir effect or diagenesis.

  14. Study on the essential variables for pipe outer surface irradiated laser stress improvement process (L-SIP). Development of pipe outer surface irradiated laser stress improvement process (L-SIP)

    International Nuclear Information System (INIS)

    Ohta, Takahiro; Kamo, Kazuhiko; Muroya, Itaru; Asada, Seiji; Nakamura, Yasuo

    2009-01-01

    The new process called L-SIP (outer surface irradiated Laser Stress Improvement Process) is developed to improve the tensile residual stress of the inner surface near the butt welded joints of pipes in the compression stress. The temperature gradient occurs in the thickness of pipes in heating the outer surface rapidly by laser beam. By the thermal expansion difference between the inner surface and the outer surface, the compression stress occurs near the inner surface of pipes. In this paper, the essential variables for L-SIP is studied by experimental and FEM analysis. The range of the essential variables for L-SIP, which are defined by thermo-elastic FEM analysis, are Tmax=550 - 650degC, L Q /√rh ≥ 3, W Q /√rh ≥ 1.7, and, 0.04 ≤ F 0 ≤ 0.10 where Tmax is maximum temperature on the monitor point of the outer surface, F 0 is k x τ 0 /h 2 , k is thermal diffusivity coefficient, τ 0 is the temperature rise time from 100degC to maximum temperature on the monitor point of the outer surface, W Q is τ 0 x v, υ is moving velocity, L Q is the uniform temperature length in the axial direction, h is thickness of the pipe, and r is average radius of the pipe. It is showed by thermo-elastic-plastic FEM analysis that the residual stresses near the inner surface of pipes are improved in 4 different size pipes under the same essential variables. L-SIP is actually applied to welding joints of 4B x Sch160 and 2B x Sch80 SUS304 type stainless steel pipes within the defined range of the essential variables. The measured welding residual stresses on the inner surface near the welding joints are tensile. The residual stresses on the inner surface change to compression in all joints by L-SIP. (author)

  15. Modeling Surface Processes Occurring on Moons of the Outer Solar System

    Science.gov (United States)

    Umurhan, O. M.; White, O. L.; Moore, J. M.; Howard, A. D.; Schenk, P.

    2016-12-01

    A variety of processes, some with familiar terrestrial analogs, are known to take place on moon surfaces in the outer solar system. In this talk, we discuss the observed features of mass wasting and surface transport seen on both Jupiter's moon Calisto and one of Saturn's Trojan moons Helene. We provide a number of numerical models using upgraded version of MARSSIM in support of several hypotheses suggested on behalf of the observations made regarding these objects. Calisto exhibits rolling plains of low albedo materials surrounding relatively high jutting peaks harboring high albedo deposits. Our modeling supports the interpretation that Calisto's surface is a record of erosion driven by the sublimation of CO2 and H2O contained in the bedrock. Both solar insolation and surface re-radiation drives the sublimation leaving behind debris which we interpret to be the observed darkened regolith and, further, the high albedo peaks are water ice deposits on surface cold traps. On the other hand, the 45 km scale Helene, being a milligravity environment, exhibits mysterious looking streaks and grooves of very high albedo materials extending for several kilometers with a down-sloping grade of 7o-9o. Helene's cratered terrain also shows evidence of narrowed septa. The observed surface features suggest some type of advective processes are at play in this system. Our modeling lends support to the suggestion that Helene's surface materials behave as a Bingham plastic material - our flow modeling with such rheologies can reproduce the observed pattern of streakiness depending upon the smoothness of the underlying bedrock; the overall gradients observed; and the narrowed septa of inter-crater regions.

  16. Elastic-plastic fracture mechanics analysis of a pressure vessel with an axial outer surface flaw

    International Nuclear Information System (INIS)

    Aurich, D.

    1988-04-01

    Elastic-plastic finite element analyses of a test vessel (steel 1.6310=20 MnMoNi 55) with a semi-elliptical axial outer surface crack have been performed. The variations of J and CTOD along the crack front and the stresse state in the vicinity of the crack are presented. The applicability of approaches to determine J is examined. The FE results are compared with the experimental data. The results are analyzed with respect to the validity of J-controlled crack growth. It will be shown that the local ductile crack growth and, especially, the 'canoe effect' for a semi-elliptical crack can only be described correctly if local J R -curves are used which account for the varying triaxiality of the stress state along the crack front. (orig./HP) [de

  17. Xylella fastidiosa outer membrane vesicles modulate plant colonization by blocking attachment to surfaces.

    Science.gov (United States)

    Ionescu, Michael; Zaini, Paulo A; Baccari, Clelia; Tran, Sophia; da Silva, Aline M; Lindow, Steven E

    2014-09-16

    Outer membrane vesicles (OMVs) of Gram-negative bacteria have been studied intensively in recent years, primarily in their role in delivering virulence factors and antigens during pathogenesis. However, the near ubiquity of their production suggests that they may play other roles, such as responding to envelope stress or trafficking various cargoes to prevent dilution or degradation by other bacterial species. Here we show that OMVs produced by Xylella fastidiosa, a xylem-colonizing plant pathogenic bacterium, block its interaction with various surfaces such as the walls of xylem vessels in host plants. The release of OMVs was suppressed by the diffusible signal factor-dependent quorum-sensing system, and a X. fastidiosa ΔrpfF mutant in which quorum signaling was disrupted was both much more virulent to plants and less adhesive to glass and plant surfaces than the WT strain. The higher virulence of the ΔrpfF mutant was associated with fivefold higher numbers of OMVs recovered from xylem sap of infected plants. The frequency of attachment of X. fastidiosa to xylem vessels was 20-fold lower in the presence of OMVs than in their absence. OMV production thus is a strategy used by X. fastidiosa cells to adjust attachment to surfaces in its transition from adhesive cells capable of insect transmission to an "exploratory" lifestyle for systemic spread within the plant host which would be hindered by attachment. OMV production may contribute to the movement of other bacteria in porous environments by similarly reducing their contact with environmental constituents.

  18. Does host complement kill Borrelia burgdorferi within ticks?

    Science.gov (United States)

    Rathinavelu, Sivaprakash; Broadwater, Anne; de Silva, Aravinda M

    2003-02-01

    The Lyme disease spirochete, Borrelia burgdorferi, inhabits the gut lumen of the tick vector. At this location the spirochete is exposed to host blood when a tick feeds. We report here on studies that were done with normal and complement-deficient (C3-knockout) mice to determine if the host complement system killed spirochetes within the vector. We found that spirochete numbers within feeding nymphs were not influenced by complement, most likely because host complement was inactivated within the vector. The Lyme disease outer surface protein A (OspA) vaccine is a transmission-blocking vaccine that targets spirochetes in the vector. In experiments with mice hyperimmunized with OspA, complement was not required to kill spirochetes within nymphs and to block transmission from nymphs to the vaccinated host. However, host complement did enhance the ability of OspA antibody to block larvae from acquiring spirochetes. Thus, the effects of OspA antibody on nymphal transmission and larval acquisition appear to be based on different mechanisms.

  19. Simultaneous and long-lasting hydrophilization of inner and outer wall surfaces of polytetrafluoroethylene tubes by transferring atmospheric pressure plasmas

    International Nuclear Information System (INIS)

    Chen, Faze; Song, Jinlong; Huang, Shuai; Xu, Wenji; Sun, Jing; Liu, Xin; Xu, Sihao; Xia, Guangqing; Yang, Dezheng

    2016-01-01

    Plasma hydrophilization is a general method to increase the surface free energy of materials. However, only a few works about plasma modification focus on the hydrophilization of tube inner and outer walls. In this paper, we realize simultaneous and long-lasting plasma hydrophilization on the inner and outer walls of polytetrafluoroethylene (PTFE) tubes by atmospheric pressure plasmas (APPs). Specifically, an Ar atmospheric pressure plasma jet (APPJ) is used to modify the PTFE tube’s outer wall and meanwhile to induce transferred He APP inside the PTFE tube to modify its inner wall surface. The optical emission spectrum (OES) shows that the plasmas contain many chemically active species, which are known as enablers for various applications. Water contact angle (WCA) measurements, x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) are used to characterize the plasma hydrophilization. Results demonstrate that the wettability of the tube walls are well improved due to the replacement of the surface fluorine by oxygen and the change of surface roughness. The obtained hydrophilicity decreases slowly during more than 180 d aging, indicating a long-lasting hydrophilization. The results presented here clearly demonstrate the great potential of transferring APPs for surface modification of the tube’s inner and outer walls simultaneously. (paper)

  20. Methylation and in vivo expression of the surface-exposed Leptospira interrogans outer-membrane protein OmpL32.

    Science.gov (United States)

    Eshghi, Azad; Pinne, Marija; Haake, David A; Zuerner, Richard L; Frank, Ami; Cameron, Caroline E

    2012-03-01

    Recent studies have revealed that bacterial protein methylation is a widespread post-translational modification that is required for virulence in selected pathogenic bacteria. In particular, altered methylation of outer-membrane proteins has been shown to modulate the effectiveness of the host immune response. In this study, 2D gel electrophoresis combined with MALDI-TOF MS identified a Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130 protein, corresponding to ORF LIC11848, which undergoes extensive and differential methylation of glutamic acid residues. Immunofluorescence microscopy implicated LIC11848 as a surface-exposed outer-membrane protein, prompting the designation OmpL32. Indirect immunofluorescence microscopy of golden Syrian hamster liver and kidney sections revealed expression of OmpL32 during colonization of these organs. Identification of methylated surface-exposed outer-membrane proteins, such as OmpL32, provides a foundation for delineating the role of this post-translational modification in leptospiral virulence.

  1. On the geodesic incompleteness of spacetimes containing marginally (outer) trapped surfaces

    International Nuclear Information System (INIS)

    Costa e Silva, I P

    2012-01-01

    In a recent paper, Eichmair et al (2012 arXiv:1204.0278v1) have proved a Gannon–Lee-type singularity theorem based on the existence of marginally outer trapped surfaces (MOTS) on noncompact initial data sets for globally hyperbolic spacetimes. A natural question is whether the corresponding incomplete geodesics could still be complete in a possible non-globally hyperbolic extension of spacetime. In this paper, some variants of their result are given with weaker causality assumptions, thus suggesting that the answer is generically negative, at least if the putative extension has no closed timelike curves. We consider first marginally trapped surfaces (MTS) in chronological spacetimes, introducing the natural notion of a generic MTS, a notion also applicable to MOTS. In particular, a Hawking–Penrose-type singularity theorem is proven in chronological spacetimes with dimension n ⩾ 3 containing a generic MTS. Such surfaces naturally arise as cross-sections of quasi-local generalizations of black hole horizons, such as dynamical and trapping horizons, and we discuss some natural conditions which ensure the existence of MTS in initial data sets. Nevertheless, much of the more recent literature has focused on MOTS rather than MTS as quasi-local substitutes for the description of black holes, as they are arguably more natural and easier to handle in a number of situations. It is therefore pertinent to ask to what extent one can deduce the existence of singularities in the presence of MOTS alone. We address this issue and show that singularities indeed arise in the presence of generic MOTS, but under slightly stronger causal conditions than those in the case of MTS (specifically, for causally simple spacetimes). On the other hand, we show that with additional conditions on the MOTS itself, namely that it is either the boundary of a compact spatial region, or strictly stable in a suitable sense, a Penrose–Hawking-type singularity theorem can still be established for

  2. Sedimentology and geochemistry of surface sediments, outer continental shelf, southern Bering Sea

    Science.gov (United States)

    Gardner, J.V.; Dean, W.E.; Vallier, T.L.

    1980-01-01

    Islands and the outer continental shelf and slope, indicates that Holocene sediment dynamics cannot be used to explain the observed distribution of surface sediment derived from the Aleutian Islands. We suggest that this pattern is relict and resulted from sediment dynamics during lower sea levels of the Pleistocene. ?? 1980.

  3. Recombinant constructs of Borrelia burgdorferi

    Energy Technology Data Exchange (ETDEWEB)

    Dattwyler, Raymond J. (Setauket, NY); Gomes-Solecki, Maria J. C. (New York, NY); Luft, Benjamin J. (East Setauket, NY); Dunn, John J.(Bellport, NY)

    2007-02-20

    Novel chimeric nucleic acids, encoding chimeric Borrelia proteins comprising OspC or an antigenic fragment thereof and OspA or an antigenic fragment thereof, are disclosed. Chimeric proteins encoded by the nucleic acid sequences are also disclosed. The chimeric proteins are useful as vaccine immunogens against Lyme borreliosis, as well as for immunodiagnostic reagents.

  4. Laboratory Studies of Ethane Ice Relevant to Outer Solar System Surfaces

    Science.gov (United States)

    Moore, Marla H.; Hudson, Reggie; Raines, Lily

    2009-01-01

    Oort Cloud comets, as well as TNOs Makemake (2045 FYg), Quaoar, and Pluto, are known to contain ethane. However, even though this molecule is found on several outer Solar System objects relatively little information is available about its amorphous and crystalline phases. In new experiments, we have prepared ethane ices at temperatures applicable to the outer Solar System, and have heated and ion-irradiated these ices to study phase changes and ethane's radiation chemistry using mid-IR spectroscopy (2.2 - 16.6 microns). Included in our work is the meta-stable phase that exists at 35 - 55 K. These results, including newly obtained optical constants, are relevant to ground-based observational campaigns, the New Horizons mission, and supporting laboratory work. An improved understanding of solid-phase ethane may contribute to future searches for this and other hydrocarbons in the outer Solar System.

  5. Computation of the temperatures of a fluid flowing through a pipe from temperature measurements on the pipe's outer surface

    International Nuclear Information System (INIS)

    Sauer, G.

    1999-01-01

    A method for computing the temperatures of a fluid flowing through a pipe on the basis of temperatures recorded at the pipe's outer surface is presented. The heat conduction in the pipe wall is described by one-dimensional heat conduction elements. Heat transfer between fluid, pipe and surrounding is allowed for. The equation system resulting from the standard finite element discretization is reformulated to enable the computation of temperature events preceding the recorded temperature in time. It is shown that the method can be used to identify the actual fluid temperature from temperature data obtained only at the outer surface of the pipe. The temperatures in the pipe wall are computed with good accuracy even in the case of a severe thermal shock. (orig.) [de

  6. Coinfection with Borrelia burgdorferi sensu stricto and Borrelia garinii alters the course of murine Lyme borreliosis

    NARCIS (Netherlands)

    Hovius, Joppe W. R.; Li, Xin; Ramamoorthi, Nandhini; van Dam, Alje P.; Barthold, Stephen W.; van der Poll, Tom; Speelman, Peter; Fikrig, Erol

    2007-01-01

    Ixodes ricinus ticks and mice can be infected with both Borrelia burgdorferi sensu stricto and Borrelia garinii. The effect of coinfection with these two Borrelia species on the development of murine Lyme borreliosis is unknown. Therefore, we investigated whether coinfection with the

  7. In situ spectroscopic evidence for neptunium(V)-carbonate inner-sphere and outer-sphere ternary surface complexes on hematite surfaces.

    Science.gov (United States)

    Arai, Yuji; Moran, P B; Honeyman, B D; Davis, J A

    2007-06-01

    Np(V) surface speciation on hematite surfaces at pH 7-9 under pC2 = 10(-3.45) atm was investigated using X-ray absorption spectroscopy (XAS). In situ XAS analyses suggest that bis-carbonato inner-sphere and tris-carbonato outer-sphere ternary surface species coexist at the hematite-water interface at pH 7-8.8, and the fraction of outer-sphere species gradually increases from 27 to 54% with increasing pH from 7 to 8.8. The results suggest that the heretofore unknown Np(V)-carbonato ternary surface species may be important in predicting the fate and transport of Np(V) in the subsurface environment down gradient of high-level nuclear waste respositories.

  8. Mass and heat transfer at the outer surface of helical coils under single and two phase flow

    International Nuclear Information System (INIS)

    Abdel-Aziz, M.H.; Nirdosh, I.; Sedahmed, G.H.

    2016-01-01

    Highlights: • The work aims to develop reactors which need rapid temperature control. • Mass and heat transfer at the outer surface of helical coils was studied experimentally. • The experiments were conducted under gas sparing, single and two phase flow. • Variables were helical tube diameter, physical properties, and gas and liquid velocity. • Results verification in terms of natural convection and surface renewal mechanism was explained. - Abstract: The mass transfer behavior of the outer surface of vertical helical coil was studied by the electrochemical technique under single phase flow, gas sparging and two phase flow. Variables studied were helical tube diameter, physical properties of the solution, solution velocity and superficial gas velocity. The mass transfer data were correlated by dimensionless equations. Mass transfer enhancement ratio in case of two phase flow ranged from 1.1 to 4.9 compared to single phase flow. Implication of the results for the design and operation of helical coil reactors used to conduct L–S exothermic diffusion controlled reactions which need rapid temperature control were outlined. In this case the inner coil surface will act as a cooler while the outer surface will act a reaction surface. Immobilized enzyme catalyzed biochemical reactions where heat sensitive materials may be involved represent an example for the reactions which can employ the helical coil reactor. Also the importance of the results in the design of and operation of diffusion controlled membrane processes which employ helical coil membrane was noted. In view of the analogy between heat and mass transfer the possibility of using the results in the design and operation of helical coil heat exchangers was highlighted.

  9. A Miniaturized Seismometer for Surface Measurements in the Outer Solar System

    Science.gov (United States)

    Banerdt, W. B.; Pike, W. T.

    2001-01-01

    Seismology is a powerful tool for investigating the inner structure and dynamic processes of a planetary body. The interior structure information derived from seismic measurements is complementary to other methods of probing the subsurface (such as gravity and electromagnetics), both in terms of spatial and depth resolution and the relevant types of material properties being sensed. The propagation of seismic waves is sensitive to composition (via density and elastic parameters), temperature (via attenuation) and physical state (solid vs. liquid). In addition, the seismicity (level and distribution in space and time of seismic activity) provides information on the impact flux and tectonic forces currently active within the body. The major satellites of the outer solar system provide obvious targets for seismic investigations. In addition, small bodies, such as asteroids and comets, can also benefit from seismic measurements. We have developed an extremely small, lightweight, low-power seismometer for planetary applications which is ideally suited for use in the outer solar system. This instrument has previously been proposed and selected for use on a comet (on the Rosetta Lander, subsequently deselected for programmatic reasons) and Mars (on the NetLander mission). Additional information is contained in the original extended abstract.

  10. Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells.

    Directory of Open Access Journals (Sweden)

    Kelly P Nevin

    Full Text Available The mechanisms by which Geobacter sulfurreducens transfers electrons through relatively thick (>50 microm biofilms to electrodes acting as a sole electron acceptor were investigated. Biofilms of Geobacter sulfurreducens were grown either in flow-through systems with graphite anodes as the electron acceptor or on the same graphite surface, but with fumarate as the sole electron acceptor. Fumarate-grown biofilms were not immediately capable of significant current production, suggesting substantial physiological differences from current-producing biofilms. Microarray analysis revealed 13 genes in current-harvesting biofilms that had significantly higher transcript levels. The greatest increases were for pilA, the gene immediately downstream of pilA, and the genes for two outer c-type membrane cytochromes, OmcB and OmcZ. Down-regulated genes included the genes for the outer-membrane c-type cytochromes, OmcS and OmcT. Results of quantitative RT-PCR of gene transcript levels during biofilm growth were consistent with microarray results. OmcZ and the outer-surface c-type cytochrome, OmcE, were more abundant and OmcS was less abundant in current-harvesting cells. Strains in which pilA, the gene immediately downstream from pilA, omcB, omcS, omcE, or omcZ was deleted demonstrated that only deletion of pilA or omcZ severely inhibited current production and biofilm formation in current-harvesting mode. In contrast, these gene deletions had no impact on biofilm formation on graphite surfaces when fumarate served as the electron acceptor. These results suggest that biofilms grown harvesting current are specifically poised for electron transfer to electrodes and that, in addition to pili, OmcZ is a key component in electron transfer through differentiated G. sulfurreducens biofilms to electrodes.

  11. Iodo-gen-catalysed iodination for identification of surface-exposed outer membrane proteins of Escherichia coli K12

    International Nuclear Information System (INIS)

    Ferreira, L.C.S.; Almeida, D.F. de

    1987-01-01

    Surface proteins of Escherichia coli K12 were identified by radiolabelling using 1,3,4,6 - tatrachloro, 3-alpha, 6-alpha - diphenylgycoluryl (Iodo-Gen) and 131 I. Labelled proteins were localized in the outer membrane of the cells. Using this technique it has been possible to observe technique it has been possible to observe that the eletrophoretic pattern of surface proteins changes according to the growth phases in culture. Radiolabelling of E.coli cells inculbated at 42 0 C showed that the syntheses of two surface proteins were temperature-inducible. At least one such protein may be involved in the process of cell division in E.coli K12. (author) [pt

  12. Iodo-gen-catalysed iodination for identification of surface-exposed outer membrane proteins of Escherichia coli K12

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, L C.S.; Almeida, D.F. de

    1987-12-01

    Surface proteins of Escherichia coli K12 were identified by radiolabelling using 1,3,4,6 - tatrachloro, 3-alpha, 6-alpha - diphenylgycoluryl (Iodo-Gen) and /sup 131/I. Labelled proteins were localized in the outer membrane of the cells. Using this technique it has been possible to observe technique it has been possible to observe that the eletrophoretic pattern of surface proteins changes according to the growth phases in culture. Radiolabelling of E.coli cells inculbated at 42/sup 0/C showed that the syntheses of two surface proteins were temperature-inducible. At least one such protein may be involved in the process of cell division in E.coli K12.

  13. Surface expression, single-channel analysis and membrane topology of recombinant Chlamydia trachomatis Major Outer Membrane Protein

    Directory of Open Access Journals (Sweden)

    McClafferty Heather

    2005-01-01

    Full Text Available Abstract Background Chlamydial bacteria are obligate intracellular pathogens containing a cysteine-rich porin (Major Outer Membrane Protein, MOMP with important structural and, in many species, immunity-related roles. MOMP forms extensive disulphide bonds with other chlamydial proteins, and is difficult to purify. Leaderless, recombinant MOMPs expressed in E. coli have yet to be refolded from inclusion bodies, and although leadered MOMP can be expressed in E. coli cells, it often misfolds and aggregates. We aimed to improve the surface expression of correctly folded MOMP to investigate the membrane topology of the protein, and provide a system to display native and modified MOMP epitopes. Results C. trachomatis MOMP was expressed on the surface of E. coli cells (including "porin knockout" cells after optimizing leader sequence, temperature and medium composition, and the protein was functionally reconstituted at the single-channel level to confirm it was folded correctly. Recombinant MOMP formed oligomers even in the absence of its 9 cysteine residues, and the unmodified protein also formed inter- and intra-subunit disulphide bonds. Its topology was modeled as a (16-stranded β-barrel, and specific structural predictions were tested by removing each of the four putative surface-exposed loops corresponding to highly immunogenic variable sequence (VS domains, and one or two of the putative transmembrane strands. The deletion of predicted external loops did not prevent folding and incorporation of MOMP into the E. coli outer membrane, in contrast to the removal of predicted transmembrane strands. Conclusions C. trachomatis MOMP was functionally expressed on the surface of E. coli cells under newly optimized conditions. Tests of its predicted membrane topology were consistent with β-barrel oligomers in which major immunogenic regions are displayed on surface-exposed loops. Functional surface expression, coupled with improved understanding of MOMP

  14. Study of temperature distribution of pipes heated by moving rectangular gauss distribution heat source. Development of pipe outer surface irradiated laser stress improvement process (L-SIP)

    International Nuclear Information System (INIS)

    Ohta, Takahiro; Kamo, Kazuhiko; Asada, Seiji; Terasaki, Toshio

    2009-01-01

    The new process called L-SIP (outer surface irradiated Laser Stress Improvement Process) is developed to improve the tensile residual stress of the inner surface near the butt welded joints of pipes in the compression stress. The temperature gradient occurs in the thickness of pipes in heating the outer surface rapidly by laser beam. By the thermal expansion difference between the inner surface and the outer surface, the compression stress occurs near the inner surface of pipes. In this paper, the theoretical equation for the temperature distributions of pipes heated by moving rectangular Gauss distribution heat source on the outer surface is derived. The temperature histories of pipes calculated by theoretical equation agree well with FEM analysis results. According to the theoretical equation, the controlling parameters of temperature distributions and histories are q/2a y , vh, a x /h and a y /h, where q is total heat input, a y is heat source length in the axial direction, a x is Gaussian radius of heat source in the hoop direction, ν is moving velocity, and h is thickness of the pipe. The essential variables for L-SIP, which are defined on the basis of the measured temperature histories on the outer surface of the pipe, are Tmax, F 0 =kτ 0 /h 2 , vh, W Q and L Q , where Tmax is maximum temperature on the monitor point of the outer surface, k is thermal diffusivity coefficient, τ 0 is the temperature rise time from 100degC to maximum temperature on the monitor point of the outer surface, W Q is τ 0 x ν, and L Q is the uniform temperature length in the axial direction. It is verified that the essential variables for L-SIP match the controlling parameters by the theoretical equation. (author)

  15. Immunization with a recombinant subunit OspA vaccine markedly impacts the rate of newly acquired Borrelia burgdorferi infections in client-owned dogs living in a coastal community in Maine, USA.

    Science.gov (United States)

    Eschner, Andrew K; Mugnai, Kristen

    2015-02-10

    In North America, Borrelia burgdorferi is the causative bacterial agent of canine Lyme borreliosis and is transmitted following prolonged attachment and feeding of vector ticks, Ixodes scapularis or Ixodes pacificus. Its prevention is predicated upon tick-avoidance, effective on-animal tick control and effective immunization strategies. The purpose of this study is to characterize dogs that are newly seropositive for Borrelia burgdorferi infection in relation to compliant use of a recombinant OspA canine Lyme borreliosis vaccine. Specifically, Preventive Fractions (PF) and Risk Ratios (RR) associated with the degree of vaccine compliancy (complete versus incomplete) are determined. 6,202 dogs were tested over a five year period in a single veterinary hospital utilizing a non-adjuvanted, recombinant OspA vaccine according to a 0, 1, 6 month (then yearly) protocol. Rates of newly acquired "Lyme-positive" antibody test results were compared between protocol compliant and poorly compliant (incompletely and/or non-vaccinated) dogs. Over the five-year span, one percent (range 0.39 - 1.3) of protocol compliant vaccinated, previously antibody negative dogs became seropositive for infection. Approximately twenty-one percent (range 16.8 - 33.3) of incompletely vaccinated dogs became positive for infection-specific antibodies. The Preventative Fraction for testing positive for antibodies specific for infection with Borrelia burgdorferi in any given year based on optimal vaccine compliance was, on average, 95.3% (range 93.29 - 98.08). The Risk Ratio for becoming infected with Borrelia burgdorferi antibodies in any given year if vaccine non-compliant was 21.41 (range 14.9 - 52.1). There was a high statistically significant relationship (p = <0.0001) in the observed data in terms of vaccination protocol compliance and the probability of Borrelia burgdorferi infection in each of the five years under study. The recombinant outer surface protein A (rOspA) vaccine for dogs is highly

  16. Use of CFSE staining of borreliae in studies on the interaction between borreliae and human neutrophils

    Directory of Open Access Journals (Sweden)

    Hytönen Jukka

    2006-10-01

    Full Text Available Abstract Background Species of the tick-transmitted spirochete group Borrelia burgdorferi sensu lato (B. burgdorferi cause Lyme borreliosis. Acute borrelial infection of the skin has unusual characteristics with only a mild local inflammatory response suggesting that the interaction between borreliae and the cells of the first-line defence might differ from that of other bacteria. It has been reported that human neutrophils phagocytose motile borreliae through an unconventional mechanism (tube phagocytosis which is not observed with non-motile borreliae. Therefore, it would be of great interest to visualise the bacteria by a method not affecting motility and viability of borreliae to be able to study their interaction with the cells of the innate immunity. Carboxyfluorescein diacetate, succinimidyl ester (CFSE labelling has been previously used for studying the adhesion of labelled bacteria to host cells and the uptake of labelled substrates by various cells using flow cytometry. Results In this study, CFSE was shown to efficiently stain different genospecies of B. burgdorferi without affecting bacterial viability or motility. Use of CFSE staining allowed subsequent quantification of borreliae associated with human neutrophils with flow cytometry and confocal microscopy. As a result, no difference in association between different borrelial genospecies (Borrelia burgdorferi sensu stricto, Borrelia afzelii, Borrelia garinii, or between borreliae and the pyogenic bacterium Streptococcus pyogenes, with neutrophils could be detected. Borrelial virulence, on the other hand, affected association with neutrophils, with significantly higher association of a non-virulent mutant B. burgdorferi sensu stricto strain compared to the parental virulent wild type strain. Conclusion These results suggest that the flow cytometric assay using CFSE labelled borreliae is a valuable tool in the analysis of the interaction between borreliae and human neutrophils. The

  17. Fabrication of cell outer membrane mimetic polymer brush on polysulfone surface via RAFT technique

    International Nuclear Information System (INIS)

    Ma Qian; Zhang Hui; Zhao Jiang; Gong Yongkuan

    2012-01-01

    Highlights: ► Cell membrane mimetic antifouling polymer brush was grown on polysulfone surface. ► Graft density and polymerization degree were calculated from XPS results. ► Water contact angle measurements showed an extremely hydrophilic surface. ► Platelet adhesion and protein adsorption results suggested excellent antifouling ability. - Abstract: Cell membrane mimetic antifouling polymer brush was grown on polysulfone (PSF) membrane by surface-induced reversible addition–fragmentation chain transfer (RAFT) polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC). The RAFT agent immobilized PSF substrate was prepared by successive chloromethylation, amination with ethylenediamine (EDA) and amidation of the amine group of grafted EDA with the carboxylic group of 4-cyanopentanoic acid dithiobenzoate (CPAD). The surface RAFT polymerization of MPC was initiated in aqueous solution by 4,4′-azobis-4-cyanopentanoic acid (ACPA). The formation of PMPC brush coating is evidenced by X-ray photoelectron spectroscopy and water contact angle measurements. The degree of polymerization of PMPC and the polymer grafting density were calculated from the high resolution XPS spectra. The platelet adhesion and protein adsorption results showed that the PMPC-grafted PSF surface has excellent antifouling ability to resist platelet adhesion completely and suppress protein adsorption significantly. This biomimetic and bio-friendly surface RAFT polymerization strategy could be promising for a variety of biomedical applications.

  18. OPUS - Outer Planets Unified Search with Enhanced Surface Geometry Parameters - Not Just for Rings

    Science.gov (United States)

    Gordon, Mitchell; Showalter, Mark Robert; Ballard, Lisa; Tiscareno, Matthew S.; Heather, Neil

    2016-10-01

    In recent years, with the massive influx of data into the PDS from a wide array of missions and instruments, finding the precise data you need has been an ongoing challenge. For remote sensing data obtained from Jupiter to Pluto, that challenge is being addressed by the Outer Planets Unified Search, more commonly known as OPUS.OPUS is a powerful search tool available at the PDS Ring-Moon Systems Node (RMS) - formerly the PDS Rings Node. While OPUS was originally designed with ring data in mind, its capabilities have been extended to include all of the targets within an instrument's field of view. OPUS provides preview images of search results, and produces a zip file for easy download of selected products, including a table of user specified metadata. For Cassini ISS and Voyager ISS we have generated and include calibrated versions of every image.Currently OPUS supports data returned by Cassini ISS, UVIS, VIMS, and CIRS (Saturn data through June 2010), New Horizons Jupiter LORRI, Galileo SSI, Voyager ISS and IRIS, and Hubble (ACS, WFC3 and WFPC2).At the RMS Node, we have developed and incorporated into OPUS detailed geometric metadata, based on the most recent SPICE kernels, for all of the bodies in the Cassini Saturn observations. This extensive set of geometric metadata is unique to the RMS Node and enables search constraints such as latitudes and longitudes (Saturn, Titan, and icy satellites), viewing and illumination geometry (phase, incidence and emission angles), and distances and resolution.Our near term plans include adding the full set of Cassini CIRS Saturn data (with enhanced geometry), New Horizons MVIC Jupiter encounter images, New Horizons LORRI and MVIC Pluto data, HST STIS observations, and Cassini and Voyager ring occultations. We also plan to develop enhanced geometric metadata for the New Horizons LORRI and MVIC instruments for both the Jupiter and the Pluto encounters.OPUS: http://pds-rings.seti.org/search/

  19. The outer disks of early-type galaxies. I. Surface-brightness profiles of barred galaxies

    NARCIS (Netherlands)

    Erwin, Peter; Pohlen, Michael; Beckman, John E.

    We present a study of 66 barred, early-type (S0-Sb) disk galaxies, focused on the disk surface brightness profile outside the bar region, with the aim of throwing light on the nature of Freeman type I and II profiles, their origins, and their possible relation to disk truncations. This paper

  20. Calculation of plastic deformation of a conical shell with the transformation of inner surface into outer one

    Directory of Open Access Journals (Sweden)

    A. I. Uvarov

    2014-01-01

    Full Text Available An analytical model of plastic deformation of a conical shell with the transformation of internal surface into outer one was developed with a use of the kinematic method. The shell material was assumed to be perfectly plastic. The theory of thin shells and the kinematic theorem of limit equilibrium were utilized in this work. Both geometric and physical nonlinearities were taken into account. Dependences for calculating radius of curvature of the intensive deformation zones, value of chain ring deformation and values of the deforming force as a function of axial displacement were determined. Analysis showed the possibility of using a conical shell to absorb energy with high efficiency. Obtained results could be used for calculation and selection of optimal parameters of the energy-absorbing elements in shock absorbers.

  1. A countermeasure for external stress corrosion cracking in piping components by means of residual stress improvement on the outer surface

    International Nuclear Information System (INIS)

    Tanaka, Yasuhiro; Umemoto, Tadahiro

    1988-01-01

    Many techniques have been proposed as countermeasures for the External Stress Corrosion Cracking (ESCC) on austenitic stainless steel piping caused by sea salt particles. However, not one seems perfect. The method proposed here is an expansion of IHSI (Induction Heating Stress Improvement) which has been successfully implemented in many nuclear power plants as a remedy for Intergranular Stress Corrossion Cracking. The proposed method named EIHSI (External IHSI) can make the residual stress compressive on the outer surface of the piping components. In order to confirm the effectiveness of EIHSI, one series of tests were conducted on a weld joint between the pipe flange and the straight pipe. The measured residual stresses and also the results of the cracking test revealed that EIHSI is a superior method to suppress the ESCC. The outline of EIHSI and the verification tests are presented in this paper. (author)

  2. Turbine airfoil with outer wall thickness indicators

    Science.gov (United States)

    Marra, John J; James, Allister W; Merrill, Gary B

    2013-08-06

    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  3. Environment on the Surfaces of the Drip Shield and Waste Package Outer Barrier

    International Nuclear Information System (INIS)

    T. Wolery

    2005-01-01

    This report provides supporting analysis of the conditions at which an aqueous solution can exist on the drip shield or waste package surfaces, including theoretical underpinning for the evolution of concentrated brines that could form by deliquescence or evaporation, and evaluation of the effects of acid-gas generation on brine composition. This analysis does not directly feed the total system performance assessment for the license application (TSPA-LA), but supports modeling and abstraction of the in-drift chemical environment (BSC 2004 [DIRS 169863]; BSC 2004 [DIRS 169860]). It also provides analyses that may support screening of features, events, and processes, and input for response to regulatory inquiries. This report emphasizes conditions of low relative humidity (RH) that, depending on temperature and chemical conditions, may be dry or may be associated with an aqueous phase containing concentrated electrolytes. Concentrated solutions at low RH may evolve by evaporative concentration of water that seeps into emplacement drifts, or by deliquescence of dust on the waste package or drip shield surfaces. The minimum RH for occurrence of aqueous conditions is calculated for various chemical systems based on current understanding of site geochemistry and equilibrium thermodynamics. The analysis makes use of known characteristics of Yucca Mountain waters and dust from existing tunnels, laboratory data, and relevant information from the technical literature and handbooks

  4. Environment on the Surfaces of the Drip Shield and Waste Package Outer Barrier

    Energy Technology Data Exchange (ETDEWEB)

    T. Wolery

    2005-02-22

    This report provides supporting analysis of the conditions at which an aqueous solution can exist on the drip shield or waste package surfaces, including theoretical underpinning for the evolution of concentrated brines that could form by deliquescence or evaporation, and evaluation of the effects of acid-gas generation on brine composition. This analysis does not directly feed the total system performance assessment for the license application (TSPA-LA), but supports modeling and abstraction of the in-drift chemical environment (BSC 2004 [DIRS 169863]; BSC 2004 [DIRS 169860]). It also provides analyses that may support screening of features, events, and processes, and input for response to regulatory inquiries. This report emphasizes conditions of low relative humidity (RH) that, depending on temperature and chemical conditions, may be dry or may be associated with an aqueous phase containing concentrated electrolytes. Concentrated solutions at low RH may evolve by evaporative concentration of water that seeps into emplacement drifts, or by deliquescence of dust on the waste package or drip shield surfaces. The minimum RH for occurrence of aqueous conditions is calculated for various chemical systems based on current understanding of site geochemistry and equilibrium thermodynamics. The analysis makes use of known characteristics of Yucca Mountain waters and dust from existing tunnels, laboratory data, and relevant information from the technical literature and handbooks.

  5. Elastic-plastic fracture mechanics analysis of a pressure vessel with an axial outer surface flaw. Pt. 2

    International Nuclear Information System (INIS)

    Brocks, W.; Kuenecke, G.

    1989-06-01

    Continuing preceding investigations, a further elastic-plastic finite element analysis of a test vessel with a semi-elliptical axial outer surface crack has been performed. The variations of J and CTOD along the crack front and the stress state in the vicinity of the crack are presented. The applicability of analytical approaches to determine J is examined. The FE results are used to analyze the experimental data with respect to the validity of J-controlled crack growth. Local J R -curves of the surface flaw are compared with J R -curves of various specimens of different geometries. Again, it became evident that the local ductile crack growth and, especially, the developing 'canoe shape' of the surface crack cannot be described by a single resistance curve which is assumed to be a material property. A method described in a previous report to predict the ductile crack growth by using local J R -curves which depend on the triaxiality of the stress state did not result in a satisfactory outcome, in the present case. The presumed reasons will be discussed. (orig.) [de

  6. Rate of mass deposition of scaling compounds from seawater on the outer surface of heat exchangers in MED evaporators

    Energy Technology Data Exchange (ETDEWEB)

    Omar, W. [Department of Natural Resources and Chemical Engineering, Tafila Technical University, Tafila (Jordan); Ulrich, J. [FB Ingenieurwissenschaften, Institut fuer Verfahrenstechnik/TVT, Martin-Luther-Universitaet Halle-Wittenberg, Halle (Germany)

    2006-08-15

    The scaling problem in Multi Effect Distillation (MED) evaporators is investigated by the experimental measurement of the deposition rate under different operating conditions. The measurements are conducted in a batch vessel containing artificial seawater, which is allowed to contact the outer surface of a hot pipe under controlled temperature, salinity and pH. The rate of mass deposition is higher at elevated temperature. The salinity of the seawater also influences the scaling process - an increase in salinity from 47-59 g/L leads to an increase of 75.6 % in the deposition rate. Decreasing the pH value of seawater to 2.01 results in a complete inhibition of scaling, whereas the severity of the scaling increases in neutral and basic mediums. Polyacrylic acid is tested as an antifoulant and it was found that its presence in seawater reduces the scaling process. The nature of the heat transfer surface material also plays an important role in the scaling process. It is found experimentally that the rate of scaling is higher in the case of a Cu-Ni alloy as the surface material of the tube rather than stainless steel. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  7. Delineation of a New Species of the Borrelia burgdorferi Sensu Lato Complex, Borrelia americana sp. nov

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Lin, T.; Gao, L.; Grubhoffer, Libor; Oliver, J. H., Jr.

    2009-01-01

    Roč. 47, č. 12 (2009), s. 3875-3880 ISSN 0095-1137 R&D Projects: GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : multilocus sequence analysis * B. burgdorferi sl complex * new borrelia species * Borrelia americana Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 4.162, year: 2009

  8. Lipid exchange between Borrelia burgdorferi and host cells.

    Directory of Open Access Journals (Sweden)

    Jameson T Crowley

    2013-01-01

    Full Text Available Borrelia burgdorferi, the agent of Lyme disease, has cholesterol and cholesterol-glycolipids that are essential for bacterial fitness, are antigenic, and could be important in mediating interactions with cells of the eukaryotic host. We show that the spirochetes can acquire cholesterol from plasma membranes of epithelial cells. In addition, through fluorescent and confocal microscopy combined with biochemical approaches, we demonstrated that B. burgdorferi labeled with the fluorescent cholesterol analog BODIPY-cholesterol or (3H-labeled cholesterol transfer both cholesterol and cholesterol-glycolipids to HeLa cells. The transfer occurs through two different mechanisms, by direct contact between the bacteria and eukaryotic cell and/or through release of outer membrane vesicles. Thus, two-way lipid exchange between spirochetes and host cells can occur. This lipid exchange could be an important process that contributes to the pathogenesis of Lyme disease.

  9. Exposure of outer membrane proteins on the surface of Pseudomonas aeruginosa PA01 revealed by labelling with [125I]lactoperoxidase

    International Nuclear Information System (INIS)

    Lambert, P.A.; Booth, B.R.

    1982-01-01

    The authors have investigated the exposure of the major outer membrane proteins on the cell surface by treating whole cells of P. aeruginosa with [ 125 I]lactoperoxidase. This reagent catalyses the iodination of tyrosine and histidine residues of proteins in the presence of hydrogen peroxide. It is too large to penetrate the outer membrane (Msub(r) 77500), therefore it is assumed to label only those proteins which have such residues exposed on the cell surface and has been applied to a number of Gram-negative organisms. It is found that F was the major labelled protein, D1 and/or D2 were less heavily labelled, and G was very faintly labelled. In addition, two proteins (Msub(r) 72500 and 38000) which did not appear to be major outer membrane proteins were labelled. (Auth.)

  10. Pseudomonas aeruginosa outer membrane vesicles triggered by human mucosal fluid and lysozyme can prime host tissue surfaces for bacterial adhesion

    Directory of Open Access Journals (Sweden)

    Matteo Maria Emiliano Metruccio

    2016-06-01

    Full Text Available Pseudomonas aeruginosa is a leading cause of human morbidity and mortality that often targets epithelial surfaces. Host immunocompromise, or the presence of indwelling medical devices, including contact lenses, can predispose to infection. While medical devices are known to accumulate bacterial biofilms, it is not well understood why resistant epithelial surfaces become susceptible to P. aeruginosa. Many bacteria, including P. aeruginosa, release Outer Membrane Vesicles (OMVs in response to stress that can fuse with host cells to alter their function. Here, we tested the hypothesis that mucosal fluid can trigger OMV release to compromise an epithelial barrier. This was tested using tear fluid and corneal epithelial cells in vitro and in vivo. After 1 h both human tear fluid, and the tear component lysozyme, greatly enhanced OMV release from P. aeruginosa strain PAO1 compared to PBS controls (~100 fold. TEM and SDS-PAGE showed tear fluid and lysozyme-induced OMVs were similar in size and protein composition, but differed from biofilm-harvested OMVs, the latter smaller with fewer proteins. Lysozyme-induced OMVs were cytotoxic to human corneal epithelial cells in vitro and murine corneal epithelium in vivo. OMV exposure in vivo enhanced Ly6G/C expression at the corneal surface, suggesting myeloid cell recruitment, and primed the cornea for bacterial adhesion (~4-fold, P < 0.01. Sonication disrupted OMVs retained cytotoxic activity, but did not promote adhesion, suggesting the latter required OMV-mediated events beyond cell killing. These data suggest that mucosal fluid induced P. aeruginosa OMVs could contribute to loss of epithelial barrier function during medical device-related infections.

  11. Analysis of influence of heat exchange conditions on the outer surface of the lithium-ion battery to electrolyte temperature under the conditions of high current loads

    Directory of Open Access Journals (Sweden)

    Krasnoshlykov Alexander

    2017-01-01

    Full Text Available Numerical analysis of thermal conditions of a lithium-ion battery using the software package ANSYS Electric and ANSYS Fluent has been carried out. Time dependence of the electrolyte temperature on the various heat exchange conditions on the outer surface has been obtained.

  12. Whole-Genome Sequences of Two Borrelia afzelii and Two Borrelia garinii Lyme Disease Agent Isolates

    Energy Technology Data Exchange (ETDEWEB)

    Casjens, S.R.; Dunn, J.; Mongodin, E. F.; Qiu, W.-G.; Luft, B. J.; Fraser-Liggett, C. M.; Schutzer, S. E.

    2011-12-01

    Human Lyme disease is commonly caused by several species of spirochetes in the Borrelia genus. In Eurasia these species are largely Borrelia afzelii, B. garinii, B. burgdorferi, and B. bavariensis sp. nov. Whole-genome sequencing is an excellent tool for investigating and understanding the influence of bacterial diversity on the pathogenesis and etiology of Lyme disease. We report here the whole-genome sequences of four isolates from two of the Borrelia species that cause human Lyme disease, B. afzelii isolates ACA-1 and PKo and B. garinii isolates PBr and Far04.

  13. Identification and functional characterisation of Complement Regulator Acquiring Surface Protein-1 of serum resistant Borrelia garinii OspA serotype 4

    Directory of Open Access Journals (Sweden)

    Zipfel Peter F

    2010-02-01

    Full Text Available Abstract Background B. burgdorferi sensu lato (sl is the etiological agent of Lyme borreliosis in humans. Spirochetes have adapted themselves to the human immune system in many distinct ways. One important immune escape mechanism for evading complement activation is the binding of complement regulators Factor H (CFH or Factor H-like protein1 (FHL-1 to Complement Regulator-Acquiring Surface Proteins (CRASPs. Results We demonstrate that B. garinii OspA serotype 4 (ST4 PBi resist complement-mediated killing by binding of FHL-1. To identify the primary ligands of FHL-1 four CspA orthologs from B. garinii ST4 PBi were cloned and tested for binding to human CFH and FHL-1. Orthologs BGA66 and BGA71 were found to be able to bind both complement regulators but with different intensities. In addition, all CspA orthologs were tested for binding to mammalian and avian CFH. Distinct orthologs were able to bind to CFH of different animal origins. Conclusions B. garinii ST4 PBi is able to evade complement killing and it can bind FHL-1 to membrane expressed proteins. Recombinant proteins BGA66 can bind FHL-1 and human CFH, while BGA71 can bind only FHL-1. All recombinant CspA orthologs from B. garinii ST4 PBi can bind CFH from different animal origins. This partly explains the wide variety of animals that can be infected by B. garinii.

  14. Borrelia sp. phylogenetically different from Lyme disease- and relapsing fever-related Borrelia spp. in Amblyomma varanense from Python reticulatus.

    Science.gov (United States)

    Trinachartvanit, Wachareeporn; Hirunkanokpun, Supanee; Sudsangiem, Ronnayuth; Lijuan, Wanwisa; Boonkusol, Duangjai; Baimai, Visut; Ahantarig, Arunee

    2016-06-24

    Species of the genus Borrelia are causative agents of Lyme disease and relapsing fever. Lyme disease is the most commonly reported vector-borne disease in the northern hemisphere. However, in some parts of the world Lyme borreliosis and relapsing fever may be caused by novel Borrelia genotypes. Herein, we report the presence of a Borrelia sp. in an Amblyomma varanense collected from Python reticulatus. Ticks were collected from snakes, identified to species level and examined by PCR for the presence of Borrelia spp. flaB and 16S rRNA genes. Phylogenetic trees were constructed using the neighbour-joining method. Three A. varanense ticks collected from P. reticulatus were positive for a unique Borrelia sp., which was phylogenetically divergent from both Lyme disease- and relapsing fever-associated Borrelia spp. The results of this study suggest for the first time that there is a Borrelia sp. in A. varanense tick in the snake P. reticulatus that might be novel.

  15. THE HUBBLE WIDE FIELD CAMERA 3 TEST OF SURFACES IN THE OUTER SOLAR SYSTEM: SPECTRAL VARIATION ON KUIPER BELT OBJECTS

    International Nuclear Information System (INIS)

    Fraser, Wesley C.; Brown, Michael E.; Glass, Florian

    2015-01-01

    Here, we present additional photometry of targets observed as part of the Hubble Wide Field Camera 3 (WFC3) Test of Surfaces in the Outer Solar System. Twelve targets were re-observed with the WFC3 in the optical and NIR wavebands designed to complement those used during the first visit. Additionally, all of the observations originally presented by Fraser and Brown were reanalyzed through the same updated photometry pipeline. A re-analysis of the optical and NIR color distribution reveals a bifurcated optical color distribution and only two identifiable spectral classes, each of which occupies a broad range of colors and has correlated optical and NIR colors, in agreement with our previous findings. We report the detection of significant spectral variations on five targets which cannot be attributed to photometry errors, cosmic rays, point-spread function or sensitivity variations, or other image artifacts capable of explaining the magnitude of the variation. The spectrally variable objects are found to have a broad range of dynamical classes and absolute magnitudes, exhibit a broad range of apparent magnitude variations, and are found in both compositional classes. The spectrally variable objects with sufficiently accurate colors for spectral classification maintain their membership, belonging to the same class at both epochs. 2005 TV189 exhibits a sufficiently broad difference in color at the two epochs that span the full range of colors of the neutral class. This strongly argues that the neutral class is one single class with a broad range of colors, rather than the combination of multiple overlapping classes

  16. Outer magnetosphere

    International Nuclear Information System (INIS)

    Schardt, A.W.; Behannon, K.W.; Lepping, R.P.; Carbary, J.F.; Eviatar, A.; Siscoe, G.L.

    1984-01-01

    Similarities between the Saturnian and terrestrial outer magnetosphere are examined. Saturn, like earth, has a fully developed magnetic tail, 80 to 100 RS in diameter. One major difference between the two outer magnetospheres is the hydrogen and nitrogen torus produced by Titan. This plasma is, in general, convected in the corotation direction at nearly the rigid corotation speed. Energies of magnetospheric particles extend to above 500 keV. In contrast, interplanetary protons and ions above 2 MeV have free access to the outer magnetosphere to distances well below the Stormer cutoff. This access presumably occurs through the magnetotail. In addition to the H+, H2+, and H3+ ions primarily of local origin, energetic He, C, N, and O ions are found with solar composition. Their flux can be substantially enhanced over that of interplanetary ions at energies of 0.2 to 0.4 MeV/nuc

  17. Borrelia bissettiae sp. nov. and Borrelia californiensis sp. nov. prevail in diverse enzootic transmission cycles.

    Science.gov (United States)

    Margos, Gabriele; Lane, Robert S; Fedorova, Natalia; Koloczek, Johannes; Piesman, Joseph; Hojgaard, Andrias; Sing, Andreas; Fingerle, Volker

    2016-03-01

    Two species of the genus Borrelia , Borrelia bissettiae sp. nov. and Borrelia californiensis sp. nov., were first described by Postic and co-workers on the basis of genetic analyses of several loci. Multilocus sequence analysis of eight housekeeping loci confirmed that these two Borrelia genomospecies are distinct members of the Borrelia burgdorferi sensu lato complex. B. bissettiae sp. nov. was initially described in transmission cycles involving Neotoma fuscipes wood rats and Ixodes pacificus ticks in California, and Neotoma mexicana and Ixodes spinipalpis in Colorado. The preferred host of B. californiensis sp. nov. appears to be the California kangaroo rat, Dipodomys californicus ; Ixodes jellisoni , I. spinipalipis and I. pacificus ticks are naturally infected with it. Thus, the ecological associations of the two genomospecies and their genetic distance from all other known Borrelia genomospecies species justify their description as separate genomospecies: B. bissettiae sp. nov. (type strain DN127 T  = DSM 17990 T  =  CIP 109136 T ) and B. californiensis (type strain CA446 T  = DSM 17989 T  = ATCC BAA-2689 T ).

  18. Enhancement of immune response towards non-lipidized Borrelia burgdorferi recombinant OspC antigen by binding onto the surface of metallochelating nanoliposomes with entrapped lipophilic derivatives of norAbuMDP

    Czech Academy of Sciences Publication Activity Database

    Křupka, M.; Mašek, J.; Bartheldyová, E.; Turánek Knotigová, P.; Plocková, J.; Korvasová, Z.; Škrabalová, M.; Koudelka, Š.; Kulich, P.; Zachová, K.; Czerneková, L.; Strouhal, O.; Horynová, M.; Šebela, M.; Miller, A. D.; Ledvina, Miroslav; Raška, M.; Turánek, J.

    2012-01-01

    Roč. 160, č. 2 (2012), s. 374-381 ISSN 0168-3659 R&D Projects: GA ČR(CZ) GAP304/10/1951; GA TA ČR TA01011165; GA AV ČR(CZ) KAN200520703; GA AV ČR KAN200100801 Grant - others:GA UP(CZ) LF-2010-014; GA UP(CZ) LF-2011-002 Institutional research plan: CEZ:AV0Z40550506 Keywords : Borrelia burgdorferi * OspC * metallochelating liposomes * MDP Subject RIV: CC - Organic Chemistry Impact factor: 7.633, year: 2012

  19. Enzyme activities of Borrelia burgdorferi sensu lato

    Czech Academy of Sciences Publication Activity Database

    Heroldová, M.; Němec, M.; Hubálek, Zdeněk; Halouzka, Jiří

    2001-01-01

    Roč. 46, č. 3 (2001), s. 179-182 ISSN 0015-5632 R&D Projects: GA ČR GA206/00/1204 Institutional research plan: CEZ:AV0Z6093917 Keywords : Borrelia burgdorferi * Lyme disease Subject RIV: EE - Microbiology, Virology Impact factor: 0.776, year: 2001

  20. Methylation and in vivo expression of the surface-exposed Leptospira interrogans outer membrane protein OmpL32

    Science.gov (United States)

    Recent studies have revealed that bacterial protein methylation is a widespread post-translational modification that is required for virulence in selected pathogenic bacteria. In particular, altered methylation of outer membrane proteins has been shown to modulate the effectiveness of the host immu...

  1. Complement factor H-related proteins CFHR2 and CFHR5 represent novel ligands for the infection-associated CRASP proteins of Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Corinna Siegel

    2010-10-01

    Full Text Available One virulence property of Borrelia burgdorferi is its resistance to innate immunity, in particular to complement-mediated killing. Serum-resistant B. burgdorferi express up to five distinct complement regulator-acquiring surface proteins (CRASP which interact with complement regulator factor H (CFH and factor H-like protein 1 (FHL1 or factor H-related protein 1 (CFHR1. In the present study we elucidate the role of the infection-associated CRASP-3 and CRASP-5 protein to serve as ligands for additional complement regulatory proteins as well as for complement resistance of B. burgdorferi.To elucidate whether CRASP-5 and CRASP-3 interact with various human proteins, both borrelial proteins were immobilized on magnetic beads. Following incubation with human serum, bound proteins were eluted and separated by Glycine-SDS-PAGE. In addition to CFH and CFHR1, complement regulators CFHR2 and CFHR5 were identified as novel ligands for both borrelial proteins by employing MALDI-TOF. To further assess the contributions of CRASP-3 and CRASP-5 to complement resistance, a serum-sensitive B. garinii strain G1 which lacks all CFH-binding proteins was used as a valuable model for functional analyses. Both CRASPs expressed on the B. garinii outer surface bound CFH as well as CFHR1 and CFHR2 in ELISA. In contrast, live B. garinii bound CFHR1, CFHR2, and CFHR5 and only miniscute amounts of CFH as demonstrated by serum adsorption assays and FACS analyses. Further functional analysis revealed that upon NHS incubation, CRASP-3 or CRASP-5 expressing borreliae were killed by complement.In the absence of CFH and the presence of CFHR1, CFHR2 and CFHR5, assembly and integration of the membrane attack complex was not efficiently inhibited indicating that CFH in co-operation with CFHR1, CFHR2 and CFHR5 supports complement evasion of B. burgdorferi.

  2. Inductance and resistance measurement method for vessel detection and coil powering in all-surface inductive heating systems composed of outer squircle coils

    Science.gov (United States)

    Kilic, Veli Tayfun; Unal, Emre; Demir, Hilmi Volkan

    2017-05-01

    In this work, we investigate a method proposed for vessel detection and coil powering in an all-surface inductive heating system composed of outer squircle coils. Besides conventional circular coils, coils with different shapes such as outer squircle coils are used for and enable efficient all-surface inductive heating. Validity of the method, which relies on measuring inductance and resistance values of a loaded coil at different frequencies, is experimentally demonstrated for a coil with shape different from conventional circular coil. Simple setup was constructed with a small coil to model an all-surface inductive heating system. Inductance and resistance maps were generated by measuring coil's inductance and resistance values at different frequencies loaded by a plate made of different materials and located at various positions. Results show that in an induction hob for various coil geometries it is possible to detect a vessel's presence, to identify its material type and to specify its position on the hob surface by considering inductance and resistance of the coil measured on at least two different frequencies. The studied method is important in terms of enabling safe, efficient and user flexible heating in an all-surface inductive heating system by automatically detecting the vessel's presence and powering on only the coils that are loaded by the vessel with predetermined current levels.

  3. Molecular detection of Borrelia burgdorferi sensu lato

    DEFF Research Database (Denmark)

    Lager, Malin; Faller, Maximilian; Wilhelmsson, Peter

    2017-01-01

    the protocols using 16S rRNA as the target gene, however, this concordance was mainly related to cDNA as the type of template. When comparing cDNA and DNA as the type of template the analytical sensitivity was in general higher for the protocols using DNA as template regardless of the use of target gene...... molecular detection by polymerase chain reaction (PCR) may serve as a complement. Aim: The purpose of this study was to evaluate the analytical sensitivity, analytical specificity and concordance of eight different real-time PCR methods at five laboratories in Sweden, Norway and Denmark. Method: Each...... participating laboratory was asked to analyse three different sets of samples (reference panels; all blinded) i) cDNA extracted and transcribed from water spiked with cultured Borrelia strains, ii) cerebrospinal fluid spiked with cultured Borrelia strains, and iii) DNA dilution series extracted from cultured...

  4. Borrelia infection and risk of celiac disease.

    Science.gov (United States)

    Alaedini, Armin; Lebwohl, Benjamin; Wormser, Gary P; Green, Peter H; Ludvigsson, Jonas F

    2017-09-15

    Environmental factors, including infectious agents, are speculated to play a role in the rising prevalence and the geographic distribution of celiac disease, an autoimmune disorder. In the USA and Sweden where the regional variation in the frequency of celiac disease has been studied, a similarity with the geographic distribution of Lyme disease, an emerging multisystemic infection caused by Borrelia burgdorferi spirochetes, has been found, thus raising the possibility of a link. We aimed to determine if infection with Borrelia contributes to an increased risk of celiac disease. Biopsy reports from all of Sweden's pathology departments were used to identify 15,769 individuals with celiac disease. Through linkage to the nationwide Patient Register, we compared the rate of earlier occurrence of Lyme disease in the patients with celiac disease to that in 78,331 matched controls. To further assess the temporal relationship between Borrelia infection and celiac disease, we also examined the risk of subsequent Lyme disease in patients with a diagnosis of celiac disease. Twenty-five individuals (0.16%) with celiac disease had a prior diagnosis of Lyme disease, whereas 79 (0.5%) had a subsequent diagnosis of Lyme disease. A modest association between Lyme disease and celiac disease was seen both before (odds ratio, 1.61; 95% confidence interval (CI), 1.06-2.47) and after the diagnosis of celiac disease (hazard ratio, 1.82; 95% CI, 1.40-2.35), with the risk of disease being highest in the first year of follow-up. Only a minor fraction of the celiac disease patient population had a prior diagnosis of Lyme disease. The similar association between Lyme disease and celiac disease both before and after the diagnosis of celiac disease is strongly suggestive of surveillance bias as a likely contributor. Taken together, the data indicate that Borrelia infection is not a substantive risk factor in the development of celiac disease.

  5. Established Population of Blacklegged Ticks with High Infection Prevalence for the Lyme Disease Bacterium, Borrelia burgdorferi Sensu Lato, on Corkscrew Island, Kenora District, Ontario

    Science.gov (United States)

    Scott, John D.; Foley, Janet E.; Clark, Kerry L.; Anderson, John F.; Durden, Lance A.; Manord, Jodi M.; Smith, Morgan L.

    2016-01-01

    We document an established population of blacklegged ticks, Ixodes scapularis, on Corkscrew Island, Kenora District, Ontario, Canada. Primers of the outer surface protein A (OspA) gene, the flagellin (fla) gene, and the flagellin B (flaB) gene were used in the PCR assays to detect Borrelia burgdorferi sensu lato (s.l.), the Lyme disease bacterium. In all, 60 (73%) of 82 adult I. scapularis, were infected with B. burgdorferi s.l. As well, 6 (43%) of 14 unfed I. scapularis nymphs were positive for B. burgdorferi s.l. An I. scapularis larva was also collected from a deer mouse, and several unfed larvae were gathered by flagging leaf litter. Based on DNA sequencing of randomly selected Borrelia amplicons from six nymphal and adult I. scapularis ticks, primers for the flagellin (fla) and flagellin B (flaB) genes reveal the presence of B. burgdorferi sensu stricto (s.s.), a genospecies pathogenic to humans and certain domestic animals. We collected all 3 host-feeding life stages of I. scapularis in a single year, and report the northernmost established population of I. scapularis in Ontario. Corkscrew Island is hyperendemic for Lyme disease and has the highest prevalence of B. burgdorferi s.l. for any established population in Canada. Because of this very high infection prevalence, this population of I. scapularis has likely been established for decades. Of epidemiological significance, cottage owners, island visitors, outdoors enthusiasts, and medical professionals must be vigilant that B. burgdorferi s.l.-infected I. scapularis on Corkscrew Island pose a serious public health risk. PMID:27877080

  6. Preface to the special issue of PSS on "Surfaces, atmospheres and magnetospheres of the outer planets, their satellites and ring systems: Part XII″

    Science.gov (United States)

    Coustenis, A.; Atreya, S.; Castillo-Rogez, J.; Mueller-Wodarg, I.; Spilker, L.; Strazzulla, G.

    2018-06-01

    This issue contains six articles on original research and review papers presented in the past year in sessions organized during several international meetings and congresses including the European Geosciences Union (EGU), European Planetary Science Congress (EPSC) and others. The manuscripts cover recent observations and models of the atmospheres, magnetospheres and surfaces of the giant planets and their satellites based on ongoing and recent planetary missions. Concepts of architecture and payload for future space missions are also presented. The six articles in this special issue cover a variety of objects in the outer solar system ranging from Jupiter to Neptune and the possibilities for their exploration. A brief introductory summary of their findings follows.

  7. DipA, a pore-forming protein in the outer membrane of Lyme disease spirochetes exhibits specificity for the permeation of dicarboxylates.

    Directory of Open Access Journals (Sweden)

    Marcus Thein

    Full Text Available Lyme disease Borreliae are highly dependent on the uptake of nutrients provided by their hosts. Our study describes the identification of a 36 kDa protein that functions as putative dicarboxylate-specific porin in the outer membrane of Lyme disease Borrelia. The protein was purified by hydroxyapatite chromatography from Borrelia burgdorferi B31 and designated as DipA, for dicarboxylate-specific porin A. DipA was partially sequenced, and corresponding genes were identified in the genomes of B. burgdorferi B31, Borrelia garinii PBi and Borrelia afzelii PKo. DipA exhibits high homology to the Oms38 porins of relapsing fever Borreliae. B. burgdorferi DipA was characterized using the black lipid bilayer assay. The protein has a single-channel conductance of 50 pS in 1 M KCl, is slightly selective for anions with a permeability ratio for cations over anions of 0.57 in KCl and is not voltage-dependent. The channel could be partly blocked by different di- and tricarboxylic anions. Particular high stability constants up to about 28,000 l/mol (in 0.1 M KCl were obtained among the 11 tested anions for oxaloacetate, 2-oxoglutarate and citrate. The results imply that DipA forms a porin specific for dicarboxylates which may play an important role for the uptake of specific nutrients in different Borrelia species.

  8. Monte carlo calculation of the neutron effective dose rate at the outer surface of the biological shield of HTR-10 reactor

    International Nuclear Information System (INIS)

    Remetti, Romolo; Andreoli, Giulio; Keshishian, Silvina

    2012-01-01

    Highlights: ► We deal with HTR-10, that is a helium-cooled graphite-moderated pebble bed reactor. ► We carried out Monte Carlo simulation of the core by MCNP5. ► Extensive use of MCNP5 variance reduction methods has been done. ► We calculated the trend of neutron flux within the biological shield. ► We calculated neutron effective dose at the outer surface of biological shield. - Abstract: Research on experimental reactors, such as HTR-10, provide useful data about potentialities of very high temperature gas-cooled reactors (VHTR). The latter is today rated as one of the six nuclear reactor types involved in the Generation-IV International Forum (GIF) Initiative. In this study, the MCNP5 code has been employed to evaluate the neutron radiation trend vs. the biological shield's thickness and to calculate the neutron effective dose rate at the outer surface. The reactor's geometry has been completely modeled by means of lattices and universes provided by MCNP, even though some approximations were required. Monte Carlo calculations have been performed by means of a simple PC and, as a consequence, in order to obtain acceptable run times, it was made an extensive recourse to variance reduction methods.

  9. Measuring Borrelia burgdorferi Motility and Chemotaxis.

    Science.gov (United States)

    Zhang, Kai; Li, Chunhao

    2018-01-01

    Swimming plate, cell motion tracking, and capillary tube assays are very useful tools to quantitatively measure bacterial motility and chemotaxis. These methods were modified and applied to study Borrelia burgdorferi motility and chemotaxis. By using these methods, numerous motility and chemotaxis mutants have been characterized and several chemoattractants were identified. With the assistance of these tools, the role of motility and chemotaxis in the pathogenicity of B. burgdorferi has been established. In addition, these tools also facilitate the study of motility and chemotaxis in other spirochetes.

  10. Absence of Ni on the outer surface of Sr doped La 2 NiO 4 single crystals

    KAUST Repository

    Burriel, Mó nica; Wilkins, Stuart; Hill, John P.; Muñ oz-Má rquez, Miguel A.; Brongersma, Hidde H.; Kilner, John A.; Ryan, Mary P.; Skinner, Stephen J.

    2014-01-01

    A combination of surface sensitive techniques was used to determine the surface structure and chemistry of La2-xSrxNiO 4+δ. These measurements unequivocally showed that Ni is not present in the outermost atomic layer, suggesting that the accepted model with the B-site cations exposed to the environment is incorrect. © 2014 The Royal Society of Chemistry.

  11. A distance measurement between specific sites on the cytoplasmic surface of bovine rhodopsin in rod outer segment disk membranes.

    Science.gov (United States)

    Albert, A D; Watts, A; Spooner, P; Groebner, G; Young, J; Yeagle, P L

    1997-08-14

    Structural information on mammalian integral membrane proteins is scarce. As part of work on an alternative approach to the structure of bovine rhodopsin, a method was devised to obtain an intramolecular distance between two specific sites on rhodopsin while in the rod outer segment disk membrane. In this report, the distance between the rhodopsin kinase phosphorylation site(s) on the carboxyl terminal and the top of the third transmembrane helix was measured on native rhodopsin. Rhodopsin was labeled with a nuclear spin label (31P) by limited phosphorylation with rhodopsin kinase. Major phosphorylation occurs at serines 343 and 338 on the carboxyl terminal. The phosphorylated rhodopsin was then specifically labeled on cysteine 140 with an electron spin label. Magic angle spinning 31P-nuclear magnetic resonance revealed the resonance arising from the phosphorylated protein. The enhancement of the transverse relaxation of this resonance by the paramagnetic spin label was observed. The strength of this perturbation was used to determine the through-space distance between the phosphorylation site(s) and the spin label position. A distance of 18 +/- 3 A was obtained.

  12. Development and Evaluation of Compact Robot Imitating a Hermit Crab for Inspecting the Outer Surface of Pipes

    Directory of Open Access Journals (Sweden)

    Naoto Imajo

    2015-01-01

    Full Text Available Terrestrial hermit crabs which are a type of hermit crabs live on land, whereas typical hermit crabs inhabit the sea. They have an ability of climbing a tree vertically. Their claws allow them to hang on the tree. In this study, an outer-pipe inspection robot was developed. Its locomotion mechanism was developed in imitation of the terrestrial hermit crab’s claws. It is equipped with two rimless wheels. Each of the spokes is tipped with a neodymium magnet, which allows the robot to remain attached to even a vertical steel pipe. Moreover, the robot has a mechanism for adjusting the camber angle of the right and left wheels, allowing it to tightly grip pipes with different diameters. Experiments were conducted to check the performance of the robot using steel pipes with different diameters, placed horizontally, vertically, or obliquely. The robot attempted to move a certain distance along a pipe, and its success rate was measured. It was found that the robot could successfully travel along pipes with vertical orientations, although it sometimes fell from oblique or horizontal pipes. The most likely reason for this is identified and discussed. Certain results were obtained in laboratory. Further experiments in actual environment are required.

  13. Multispacer sequence typing relapsing fever Borreliae in Africa.

    Directory of Open Access Journals (Sweden)

    Haitham Elbir

    Full Text Available BACKGROUND: In Africa, relapsing fevers are neglected arthropod-borne infections caused by closely related Borrelia species. They cause mild to deadly undifferentiated fever particularly severe in pregnant women. Lack of a tool to genotype these Borrelia organisms limits knowledge regarding their reservoirs and their epidemiology. METHODOLOGY/PRINCIPAL FINDINGS: Genome sequence analysis of Borrelia crocidurae, Borrelia duttonii and Borrelia recurrentis yielded 5 intergenic spacers scattered between 10 chromosomal genes that were incorporated into a multispacer sequence typing (MST approach. Sequencing these spacers directly from human blood specimens previously found to be infected by B. recurrentis (30 specimens, B. duttonii (17 specimens and B. crocidurae (13 specimens resolved these 60 strains and the 3 type strains into 13 species-specific spacer types in the presence of negative controls. B. crocidurae comprised of 8 spacer types, B. duttonii of 3 spacer types and B. recurrentis of 2 spacer types. CONCLUSIONS/SIGNIFICANCE: Phylogenetic analyses of MST data suggested that B. duttonii, B. crocidurae and B. recurrentis are variants of a unique ancestral Borrelia species. MST proved to be a suitable approach for identifying and genotyping relapsing fever borreliae in Africa. It could be applied to both vectors and clinical specimens.

  14. Vacuum Outer-Gap Structure in Pulsar Outer Magnetospheres

    International Nuclear Information System (INIS)

    Gui-Fang, Lin; Li, Zhang

    2009-01-01

    We study the vacuum outer-gap structure in the outer magnetosphere of rotation-powered pulsars by considering the limit of trans-field height through a pair production process. In this case, the trans-field height is limited by the photon-photon pair production process and the outer boundary of the outer gap can be extended outside the light cylinder. By solving self-consistently the Poisson equation for electrical potential and the Boltzmann equations of electrons/positrons and γ-rays in a vacuum outer gap for the parameters of Vela pulsar, we obtain an approximate geometry of the outer gap, i.e. the trans-field height is limited by the pair-production process and increases with the radial distance to the star and the width of the outer gap starts at the inner boundary (near the null charge surface) and ends at the outer boundary which locates inside or outside the light cylinder depending on the inclination angle. (geophysics, astronomy, and astrophysics)

  15. Comparative genome analysis: selection pressure on the Borrelia vls cassettes is essential for infectivity

    Directory of Open Access Journals (Sweden)

    Wilske Bettina

    2006-08-01

    Full Text Available Abstract Background At least three species of Borrelia burgdorferi sensu lato (Bbsl cause tick-borne Lyme disease. Previous work including the genome analysis of B. burgdorferi B31 and B. garinii PBi suggested a highly variable plasmid part. The frequent occurrence of duplicated sequence stretches, the observed plasmid redundancy, as well as the mainly unknown function and variability of plasmid encoded genes rendered the relationships between plasmids within and between species largely unresolvable. Results To gain further insight into Borreliae genome properties we completed the plasmid sequences of B. garinii PBi, added the genome of a further species, B. afzelii PKo, to our analysis, and compared for both species the genomes of pathogenic and apathogenic strains. The core of all Bbsl genomes consists of the chromosome and two plasmids collinear between all species. We also found additional groups of plasmids, which share large parts of their sequences. This makes it very likely that these plasmids are relatively stable and share common ancestors before the diversification of Borrelia species. The analysis of the differences between B. garinii PBi and B. afzelii PKo genomes of low and high passages revealed that the loss of infectivity is accompanied in both species by a loss of similar genetic material. Whereas B. garinii PBi suffered only from the break-off of a plasmid end, B. afzelii PKo lost more material, probably an entire plasmid. In both cases the vls gene locus encoding for variable surface proteins is affected. Conclusion The complete genome sequences of a B. garinii and a B. afzelii strain facilitate further comparative studies within the genus Borrellia. Our study shows that loss of infectivity can be traced back to only one single event in B. garinii PBi: the loss of the vls cassettes possibly due to error prone gene conversion. Similar albeit extended losses in B. afzelii PKo support the hypothesis that infectivity of Borrelia

  16. Turbine airfoil with a compliant outer wall

    Science.gov (United States)

    Campbell, Christian X [Oviedo, FL; Morrison, Jay A [Oviedo, FL

    2012-04-03

    A turbine airfoil usable in a turbine engine with a cooling system and a compliant dual wall configuration configured to enable thermal expansion between inner and outer layers while eliminating stress formation in the outer layer is disclosed. The compliant dual wall configuration may be formed a dual wall formed from inner and outer layers separated by a support structure. The outer layer may be a compliant layer configured such that the outer layer may thermally expand and thereby reduce the stress within the outer layer. The outer layer may be formed from a nonplanar surface configured to thermally expand. In another embodiment, the outer layer may be planar and include a plurality of slots enabling unrestricted thermal expansion in a direction aligned with the outer layer.

  17. Outer geosciences

    International Nuclear Information System (INIS)

    Blake, R.L.

    1979-06-01

    This report presents an objective discussion of the importance of the atmospheric/solar-terrestrial system to national energy programs. A brief sketch is given of the solar-terrestrial environment, extending from the earth's surface to the sun. Processes in this natural system influence several energy activities directly or indirectly, and some present and potential energy activities can influence the natural system. It is not yet possible to assess the two-way interactions quantitatively or to evaluate the economic impact. An investment by the Department of Energy (DOE) in a long-range basic research program would be an important part of the department's mission. Existing programs by other agencies in this area of research are reviewed, and a compatible DOE program is outlined. 18 figures, 5 tables

  18. Borrelia infection and risk of non-Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Schollkopf, C.; Melbye, M.; Munksgaard, L.

    2008-01-01

    Reports of the presence of Borrelia burgdorferi DNA in malignant lymphomas have raised the hypothesis that infection with B. burgdorferi may be causally related to non-Hodgkin lymphoma (NHL) development. We conducted a Danish-Swedish case-control study including 3055 NHL patients and 3187.......9-2.0]). However, in analyses of NHL subtypes, self-reported history of B. burgdorferi infection (OR = 2.5 [1.2-5.1]) and seropositivity for anti-Borrelia antibodies (OR = 3.6 [1.8-7.4]) were both associated with risk of mantle cell lymphoma. Notably, this specific association was also observed in persons who did...... not recall Borrelia infection yet tested positive for anti-Borrelia antibodies (OR = 4.2 [2.0-8.9]). Our observations suggest a previously unreported association between B. burgdorferi infection and risk of mantle cell lymphoma Udgivelsesdato: 2008/6/15...

  19. Antimicrobial Activity of Bee Venom and Melittin against Borrelia burgdorferi

    OpenAIRE

    Kayla M. Socarras; Priyanka A. S. Theophilus; Jason P. Torres; Khusali Gupta; Eva Sapi

    2017-01-01

    Lyme disease is a tick-borne, multi-systemic disease, caused by the bacterium Borrelia burgdorferi. Though antibiotics are used as a primary treatment, relapse often occurs after the discontinuation of antimicrobial agents. The reason for relapse remains unknown, however previous studies suggest the possible presence of antibiotic resistant Borrelia round bodies, persisters and attached biofilm forms. Thus, there is an urgent need to find antimicrobial agents suitable to eliminate all known f...

  20. Does RecA have a role in Borrelia recurrentis?

    OpenAIRE

    Cutler, S.J.; Rinky, I.J.; Bonilla, E.M.

    2011-01-01

    Genomic sequencing of two relapsing fever spirochaetes showed truncation of recA in Borrelia recurrentis, but not in Borrelia duttonii. RecA has an important role among bacteria; we investigated whether this characteristic was representative of B. recurrentis, or an artefact following in vitro cultivation. We sequenced recA directly from samples of patient with louse-borne relapsing fever (B. recurrentis) or tick-borne relapsing fever (B. duttonii). We confirmed the premature stop codon in se...

  1. Device for positioning ultrasonic probes and/or television cameras on the outer surface of reactor pressure vessels

    International Nuclear Information System (INIS)

    Zipser, R.; Dose, G.F.

    1977-01-01

    The device makes possible periodical in-service inspections of welding seams and material of a reactor pressure vessel without local human presence. A 'support ring' encloses the pressure vessel in a horizontal plane with free space. It is vertically moved up and down in the space between pressure vessel and thermal shield by means of tackles. At a control desk placed in a protected area its movement is controlled and its vertical position is indicated. A 'rotating track' with its own drive is rotating remote-controlled on the 'support ring'. By a combination of the vertical with the rotating movement, an ultrasonic probe placed removably on the 'rotating hack', or a television camera will be brought to any position on the cylindrical circumference of the pressure vessel. Special devices extend the radius of action, in upward direction for inspecting the welding seams of the coolant nozzles, and in downward direction for the inspection of welds on the hemispherical bottom of the pressure vessel or on the outlet pipe nozzle placed there. The device remains installed during reactor operation, but is moved down to the lower horizontal surface of the thermal shield. Parts which are sensible to radiation like probes or television cameras and special devices will then be removed respectively mounted before beginning an inspection compaign. This position may be reached by the lower access in the biological shield and through an opening in the horizontal surface of the thermal shield. (HP) [de

  2. Apatite fission track and (U-Th)/He dating of teschenite intrusions gives time constraints on accretionary processes and development of planation surfaces in the Outer Western Carpathians

    Energy Technology Data Exchange (ETDEWEB)

    Danisik, Martin; Frisch, Wolfgang [Tuebingen Univ. (Germany). Inst. of Geosciences; Panek, Tomas [Ostrava Univ. (Czech Republic). Dept. of Physical Geography and Geoecology; Matysek, Dalibor [Technical Univ. of Ostrava (Czech Republic). Dept. of Geological Engineering; Dunkl, Istvan [Geoscience Center Goettingen (Germany). Sedimentology and Environmental Geology

    2008-09-15

    The age of planation surfaces in the Podbeskydska pahorkatina Upland in the Outer Western Carpathians (OWC, Czech Republic) is constrained by low-temperature thermochronological dating methods for the first time. Our apatite fission track and apatite (U-Th)/He data measured on teschenite intrusions show that planation surfaces in the study area formed in post-Pannonian time (>7.1 Ma) and are therefore younger than traditionally believed. This contradicts the classical concepts, which stipulate that a large regional planation surface of Pannonian age (the so-called ''midmountain level'') developed in the whole Western Carpathians. Geodynamic implications of our data are the following: (i) the investigated Tesin and Godula nappes of the OWC were buried and thermally overprinted in the accretionary wedge in different ways, and consequently experienced different cooling histories. This indicates a dynamic basin setting with an active accretionary process in a subduction zone; (ii) accretionary processes in the OWC were active already during Late Eocene times. (orig.)

  3. Characterization of biofilm formation by Borrelia burgdorferi in vitro.

    Directory of Open Access Journals (Sweden)

    Eva Sapi

    Full Text Available Borrelia burgdorferi, the causative agent of Lyme disease, has long been known to be capable of forming aggregates and colonies. It was recently demonstrated that Borrelia burgdorferi aggregate formation dramatically changes the in vitro response to hostile environments by this pathogen. In this study, we investigated the hypothesis that these aggregates are indeed biofilms, structures whose resistance to unfavorable conditions are well documented. We studied Borrelia burgdorferi for several known hallmark features of biofilm, including structural rearrangements in the aggregates, variations in development on various substrate matrices and secretion of a protective extracellular polymeric substance (EPS matrix using several modes of microscopic, cell and molecular biology techniques. The atomic force microscopic results provided evidence that multilevel rearrangements take place at different stages of aggregate development, producing a complex, continuously rearranging structure. Our results also demonstrated that Borrelia burgdorferi is capable of developing aggregates on different abiotic and biotic substrates, and is also capable of forming floating aggregates. Analyzing the extracellular substance of the aggregates for potential exopolysaccharides revealed the existence of both sulfated and non-sulfated/carboxylated substrates, predominately composed of an alginate with calcium and extracellular DNA present. In summary, we have found substantial evidence that Borrelia burgdorferi is capable of forming biofilm in vitro. Biofilm formation by Borrelia species might play an important role in their survival in diverse environmental conditions by providing refuge to individual cells.

  4. Weak Organic Acids Decrease Borrelia burgdorferi Cytoplasmic pH, Eliciting an Acid Stress Response and Impacting RpoN- and RpoS-Dependent Gene Expression

    Directory of Open Access Journals (Sweden)

    Daniel P. Dulebohn

    2017-09-01

    Full Text Available The spirochete Borrelia burgdorferi survives in its tick vector, Ixodes scapularis, or within various hosts. To transition between and survive in these distinct niches, B. burgdorferi changes its gene expression in response to environmental cues, both biochemical and physiological. Exposure of B. burgdorferi to weak monocarboxylic organic acids, including those detected in the blood meal of fed ticks, decreased the cytoplasmic pH of B. burgdorferi in vitro. A decrease in the cytoplasmic pH induced the expression of genes encoding enzymes that have been shown to restore pH homeostasis in other bacteria. These include putative coupled proton/cation exchangers, a putative Na+/H+ antiporter, a neutralizing buffer transporter, an amino acid deaminase and a proton exporting vacuolar-type VoV1 ATPase. Data presented in this report suggested that the acid stress response triggered the expression of RpoN- and RpoS-dependent genes including important virulence factors such as outer surface protein C (OspC, BBA66, and some BosR (Borreliaoxidative stress regulator-dependent genes. Because the expression of virulence factors, like OspC, are so tightly connected by RpoS to general cellular stress responses and cell physiology, it is difficult to separate transmission-promoting conditions in what is clearly a multifactorial and complex regulatory web.

  5. Absence of sodA Increases the Levels of Oxidation of Key Metabolic Determinants of Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Maria D Esteve-Gassent

    Full Text Available Borrelia burgdorferi, the causative agent of Lyme disease, alters its gene expression in response to environmental signals unique to its tick vector or vertebrate hosts. B. burgdorferi carries one superoxide dismutase gene (sodA capable of controlling intracellular superoxide levels. Previously, sodA was shown to be essential for infection of B. burgdorferi in the C3H/HeN model of Lyme disease. We employed two-dimensional electrophoresis (2-DE and immunoblot analysis with antibodies specific to carbonylated proteins to identify targets that were differentially oxidized in the soluble fractions of the sodA mutant compared to its isogenic parental control strain following treatment with an endogenous superoxide generator, methyl viologen (MV, paraquat. HPLC-ESI-MS/MS analysis of oxidized proteins revealed that several proteins of the glycolytic pathway (BB0057, BB0020, BB0348 exhibited increased carbonylation in the sodA mutant treated with MV. Levels of ATP and NAD/NADH were reduced in the sodA mutant compared with the parental strain following treatment with MV and could be attributed to increased levels of oxidation of proteins of the glycolytic pathway. In addition, a chaperone, HtpG (BB0560, and outer surface protein A (OspA, BBA15 were also observed to be oxidized in the sodA mutant. Immunoblot analysis revealed reduced levels of Outer surface protein C (OspC, Decorin binding protein A (DbpA, fibronectin binding protein (BBK32, RpoS and BosR in the sodA mutant compared to the control strains. Viable sodA mutant spirochetes could not be recovered from both gp91/phox-⁄- and iNOS deficient mice while borrelial DNA was detected in multiple tissues samples from infected mice at significantly lower levels compared to the parental strain. Taken together, these observations indicate that the increased oxidation of select borrelial determinants and reduced levels of critical pathogenesis-associated lipoproteins contribute to the in vivo deficit of

  6. Heterogeneity of Borrelia burgdorferi sensu lato and their reflection on immune response

    Czech Academy of Sciences Publication Activity Database

    Stefančíková, A.; Derdáková, M.; Tresová, Gabriela; Peťko, B.; Szestáková, E.; Škardová, I.; Čisláková, L.

    2005-01-01

    Roč. 12, č. 2 (2005), s. 211-216 ISSN 1232-1966 Institutional research plan: CEZ:AV0Z60220518 Keywords : horses * ELISA * SDS-PAGE * IgG * seroprevalence * Borrelia burgdorferi * Borrelia garinii * Borrelia afzelii Subject RIV: EC - Immunology Impact factor: 1.051, year: 2005

  7. Evidence for frequent OspC gene transfer between Borrelia valaisiana sp. nov. and other Lyme disease spirochetes

    NARCIS (Netherlands)

    Wang, G.; van Dam, A. P.; Dankert, J.

    1999-01-01

    Molecular polymorphism of the ospC gene has been reported in Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii, the spirochetes causing human Lyme borreliosis. To assess the genetic relationship between ospC genes from the recently described Borrelia valaisiana sp. nov. and

  8. Genome-Wide Mutagenesis in Borrelia burgdorferi.

    Science.gov (United States)

    Lin, Tao; Gao, Lihui

    2018-01-01

    Signature-tagged mutagenesis (STM) is a functional genomics approach to identify bacterial virulence determinants and virulence factors by simultaneously screening multiple mutants in a single host animal, and has been utilized extensively for the study of bacterial pathogenesis, host-pathogen interactions, and spirochete and tick biology. The signature-tagged transposon mutagenesis has been developed to investigate virulence determinants and pathogenesis of Borrelia burgdorferi. Mutants in genes important in virulence are identified by negative selection in which the mutants fail to colonize or disseminate in the animal host and tick vector. STM procedure combined with Luminex Flex ® Map™ technology and next-generation sequencing (e.g., Tn-seq) are the powerful high-throughput tools for the determination of Borrelia burgdorferi virulence determinants. The assessment of multiple tissue sites and two DNA resources at two different time points using Luminex Flex ® Map™ technology provides a robust data set. B. burgdorferi transposon mutant screening indicates that a high proportion of genes are the novel virulence determinants that are required for mouse and tick infection. In this protocol, an effective signature-tagged Himar1-based transposon suicide vector was developed and used to generate a sequence-defined library of nearly 4800 mutants in the infectious B. burgdorferi B31 clone. In STM, signature-tagged suicide vectors are constructed by inserting unique DNA sequences (tags) into the transposable elements. The signature-tagged transposon mutants are generated when transposon suicide vectors are transformed into an infectious B. burgdorferi clone, and the transposable element is transposed into the 5'-TA-3' sequence in the B. burgdorferi genome with the signature tag. The transposon library is created and consists of many sub-libraries, each sub-library has several hundreds of mutants with same tags. A group of mice or ticks are infected with a mixed

  9. Temporomandibular joint involvement caused by Borrelia Burgdorferi.

    Science.gov (United States)

    Lesnicar, Gorazd; Zerdoner, Danijel

    2007-12-01

    Lyme borreliosis is an endemic disease in Slovenia with an incidence of around 150 patients per 100,000 inhabitants. Although the large joints are most typically affected in Lyme borreliosis, there are also periods of disease activity with arthritis or arthralgias involving smaller joints, including the temporo-mandibular joint. During the years between 2000 and 2003, two patients with Lyme borreliosis affecting the temporo-mandibular joints were treated. The patients presented with fatigue and pain in diverse muscle groups accompanied by arthralgia, which was most pronounced in the temporomandibular joint area. None of the patients were febrile or had joint effusions. Both patients were examined by means of biochemical and serological examinations for Borrelia burgdorferi using ELISA assay and Western blot test (both for IgM and IgG), plain radiographs, MR and CT scans, and scinti-scan of the temporo-mandibular joints They both had positive serum markers for an acute B. burgdorferi infection and were treated with intravenous ceftriaxone. None of the patients had clinical or laboratory signs of chronic Lyme disease activity two and four years following therapy, respectively. Roentgenographic and nuclear magnetic resonance imaging of the temporo-mandibular joints had not shown any persistent sign of acute inflammation. There are only few reports of patients with manifest temporo-mandibular joint involvement of Lyme borreliosis in the literature. This report emphasizes the importance of differential diagnosis of acute temporo-mandibular joint arthralgia, of early diagnosis of Lyme borreliosis, and of the necessity for prompt antibiotic treatment.

  10. Monoinfections caused by Borrelia burgdorferi and Borrelia burgdorferi / Anaplasma phagocytophilum co-infections in forestry workers and farmers

    Directory of Open Access Journals (Sweden)

    Małgorzata Tokarska-Rodak

    2015-10-01

    Full Text Available Background: The presence of co-infections induced by tick-borne pathogens in humans is an important epidemiological phenomenon. This issue has attracted growing attention of doctors and people working under conditions of an increased risk of being exposed to tick bites. Material and Methods: The research group consisted of 93 individuals with current anti-immunoglobulin M/G (IgM/ IgG Borrelia burgdorferi or IgG anti-Anaplasma phagocytophilum. The respondents were identified during the screening survey in a group of farmers and foresters occupationally exposed to tick bites. The aim of the work was to analyse the frequency of antibodies to specific antigens of B. burgdorferi and the levels of cytokines in forestry workers and farmers with B. burgdorferi monoinfections and B. burgdorferi / A. phagocytophilum co-infections. Statistical analysis was performed using the Chi2, Mann-Whitney U and Kruskal-Wallis tests. Results: There is a stronger generation of IgG antibodies to B. burgdorferi antigens in patients with B. burgdorferi / A. phagocytophilum co-infections, such as variable major protein-like sequence expressed (VlsE (p < 0.05, p19 (p < 0.02, p17 (p < 0.05 and complement regulator-acquiring surface protein 3 (CRASP3 (p < 0.02 compared to persons with B. burgdorferi monoinfections. The discrepancies in the synthesis of cytokines interleukin 6 (IL-6, IL-10, and tumor necrosis factor α (TNF-α have not been found in persons with B. burgdorferi monoinfections and B. burgdorferi / A. phagocytophilum co-infection. Conclusions: The immune response directed against B. burgdorferi is stronger in patients co-infected with B. burgdorferi and A. phagocytophilum than in those with monoinfection. Med Pr 2015;66(5:645–651

  11. Population dynamics of Borrelia burgdorferi in Lyme disease

    Directory of Open Access Journals (Sweden)

    Sebastian Christoph Binder

    2012-03-01

    Full Text Available Many chronic inflammatory diseases are known to be caused by persistent bacterial or viral infections. A well-studied example is the tick-borne infection by the gram-negative Spirochaetes of the genus Borrelia in humans and other mammals, causing severe symptoms of chronic inflammation and subsequent tissue damage (Lyme Disease, particularly in large joints and the central nervous system, but also in the heart and other tissues of untreated patients. Although killed efficiently by human phagocytic cells in vitro, Borrelia exhibits a remarkably high infectivity in mice and men. In experimentally infected mice, the first immune response almost clears the infection. However, approximately one week post infection, the bacterial population recovers and reaches an even larger size before entering the chronic phase. We developed a mathematical model describing the bacterial growth and the immune response against Borrelia burgdorferi in the C3H mouse strain that has been established as an experimental model for Lyme disease. The peculiar dynamics of the infection exclude two possible mechanistic explanations for the regrowth of the almost cleared bacteria. Neither the hypothesis of bacterial dissemination to different tissue nor a limitation of phagocytic capacity were compatible with experiment. The mathematical model predicts that Borrelia recovers from the strong initial immune response by the regrowth of an immune-resistant sub-population of the bacteria. The chronic phase appears as an equilibration of bacterial growth and adaptive immunity. This result has major implications for the development of the chronic phase of Borrelia infections as well as on potential protective clinical interventions.

  12. Whole genome sequence of an unusual Borrelia burgdorferi sensu lato isolate

    Energy Technology Data Exchange (ETDEWEB)

    Casjens, S.R.; Dunn, J.; Fraser-Liggett, C. M.; Mongodin, E. F.; Qiu, W. G.; Luft, B. J.; Schutzer, S. E.

    2011-03-01

    Human Lyme disease is caused by a number of related Borrelia burgdorferi sensu lato species. We report here the complete genome sequence of Borrelia sp. isolate SV1 from Finland. This isolate is to date the closest known relative of B. burgdorferi sensu stricto, but it is sufficiently genetically distinct from that species that it and its close relatives warrant its candidacy for new-species status. We suggest that this isolate should be named 'Borrelia finlandensis.'

  13. Perpetuation of the Lyme Disease Spirochete Borrelia lusitaniae by Lizards

    Science.gov (United States)

    Richter, Dania; Matuschka, Franz-Rainer

    2006-01-01

    To determine whether the Lyme disease spirochete Borrelia lusitaniae is associated with lizards, we compared the prevalence and genospecies of spirochetes present in rodent- and lizard-associated ticks at a site where this spirochete frequently infects questing ticks. Whereas questing nymphal Ixodes ricinus ticks were infected mainly by Borrelia afzelii, one-half of the infected adult ticks harbored B. lusitaniae at our study site. Lyme disease spirochetes were more prevalent in sand lizards (Lacerta agilis) and common wall lizards (Podarcis muralis) than in small rodents. Although subadult ticks feeding on rodents acquired mainly B. afzelii, subadult ticks feeding on lizards became infected by B. lusitaniae. Genetic analysis confirmed that the spirochetes isolated from ticks feeding on lizards are members of the B. lusitaniae genospecies and resemble type strain PotiB2. At our central European study site, lizards, which were previously considered zooprophylactic for the agent of Lyme disease, appear to perpetuate B. lusitaniae. PMID:16820453

  14. Does RecA have a role in Borrelia recurrentis?

    Science.gov (United States)

    Cutler, S J; Rinky, I J; Bonilla, E M

    2011-02-01

    Genomic sequencing of two relapsing fever spirochaetes showed truncation of recA in Borrelia recurrentis, but not in Borrelia duttonii. RecA has an important role among bacteria; we investigated whether this characteristic was representative of B. recurrentis, or an artefact following in vitro cultivation. We sequenced recA directly from samples of patient with louse-borne relapsing fever (B. recurrentis) or tick-borne relapsing fever (B. duttonii). We confirmed the premature stop codon in seven louse-borne relapsing fever samples, and its absence from three tick-borne relapsing fever samples. Furthermore, specific signature polymorphisms were found that could differentiate between these highly similar spirochaetes. © 2010 The Authors. Journal Compilation © 2010 European Society of Clinical Microbiology and Infectious Diseases.

  15. Presence of Borrelia spp. DNA in ticks, but absence of Borrelia spp. and of Leptospira spp. DNA in blood of fever patients in Madagascar.

    Science.gov (United States)

    Hagen, Ralf Matthias; Frickmann, Hagen; Ehlers, Julian; Krüger, Andreas; Margos, Gabriele; Hizo-Teufel, Cecilia; Fingerle, Volker; Rakotozandrindrainy, Raphael; Kalckreuth, Vera von; Im, Justin; Pak, Gi Deok; Jeon, Hyon Jin; Rakotondrainiarivelo, Jean Philibert; Heriniaina, Jean Noël; Razafindrabe, Tsiry; Konings, Frank; May, Jürgen; Hogan, Benedikt; Ganzhorn, Jörg; Panzner, Ursula; Schwarz, Norbert Georg; Dekker, Denise; Marks, Florian; Poppert, Sven

    2018-01-01

    The occurrence of tick-borne relapsing fever and leptospirosis in humans in Madagascar remains unclear despite the presence of their potential vectors and reservoir hosts. We screened 255 Amblyomma variegatum ticks and 148 Rhipicephalus microplus ticks from Zebu cattle in Madagascar for Borrelia-specific DNA. Borrelia spp. DNA was detected in 21 Amblyomma variegatum ticks and 2 Rhipicephalus microplus ticks. One Borrelia found in one Rhipicephalus microplus showed close relationship to Borrelia theileri based on genetic distance and phylogenetic analyses on 16S rRNA and flaB sequences. The borreliae from Amblyomma variegatum could not be identified due to very low quantities of present DNA reflected by high cycle threshold values in real-time-PCR. It is uncertain whether these low numbers of Borrelia spp. are sufficient for transmission of infection from ticks to humans. In order to determine whether spirochaete infections are relevant in humans, blood samples of 1009 patients from the highlands of Madagascar with fever of unknown origin were screened for Borrelia spp. - and in addition for Leptospira spp. - by real-time PCR. No target DNA was detected, indicating a limited relevance of these pathogens for humans in the highlands of Madagascar. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Borreliae in Ixodes ricinus ticks feeding on humans

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Halouzka, Jiří; Juřicová, Zina

    2004-01-01

    Roč. 18, č. 3 (2004), s. 228-231 ISSN 0269-283X R&D Projects: GA ČR GA206/03/0726; GA AV ČR IBS6093007 Institutional research plan: CEZ:AV0Z6093917 Keywords : Borrelia burgdorferi * Ixodes ricinus * Lyme disease Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 1.405, year: 2004

  17. Longitudinal surveillance of the tick Ixodes ricinus for borreliae

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Halouzka, Jiří; Juřicová, Zina

    2003-01-01

    Roč. 17, č. 1 (2003), s. 46-51 ISSN 0269-283X R&D Projects: GA ČR GA206/00/1204; GA AV ČR IBS6093007 Institutional research plan: CEZ:AV0Z6093917 Keywords : Borrelia burgdorferi * Ixodes ricinus * Lyme disease Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 1.040, year: 2003

  18. Spirochetes, including Borrelia burgdorferi sensu lato, in mosquitoes

    Czech Academy of Sciences Publication Activity Database

    Sanogo, Yibayiri Osée; Halouzka, Jiří; Hubálek, Zdeněk

    2000-01-01

    Roč. 62, 3 Suppl. (2000), s. 288-289 ISSN 0002-9637. [Annual meeting of the American Society of Tropical Medicine and Hygiene /49./. Houston, 29.10.2000-02.11.2000] R&D Projects: GA ČR GA206/00/1234 Institutional research plan: CEZ:AV0Z6093917 Keywords : Borrelia burgdorferi Subject RIV: EE - Microbiology, Virology Impact factor: 1.765, year: 2000

  19. Does Host Complement Kill Borrelia burgdorferi within Ticks?

    OpenAIRE

    Rathinavelu, Sivaprakash; Broadwater, Anne; de Silva, Aravinda M.

    2003-01-01

    The Lyme disease spirochete, Borrelia burgdorferi, inhabits the gut lumen of the tick vector. At this location the spirochete is exposed to host blood when a tick feeds. We report here on studies that were done with normal and complement-deficient (C3-knockout) mice to determine if the host complement system killed spirochetes within the vector. We found that spirochete numbers within feeding nymphs were not influenced by complement, most likely because host complement was inactivated within ...

  20. Detection of Borrelia burgdorferi DNA in Lizards from Southern Maryland

    OpenAIRE

    SWANSON, KATHERINE I.; NORRIS, DOUGLAS E.

    2007-01-01

    Lizards serve as hosts for Ixodes ticks in the western and southeastern United States and may affect the transmission cycles of Borrelia burgdorferi in these regions. In Maryland, the role of lizards in the maintenance and transmission cycle of this pathogen has not been examined. We tested 29 lizards (Sceloporus undulatus and Eumeces spp.) and 21 ticks from these lizards for the presence of B. burgdorferi. Eight lizards were positive by polymerase chain reaction (PCR) for at least one B. bur...

  1. Characterization of the β-barrel assembly machine accessory lipoproteins from Borrelia burgdorferi.

    Science.gov (United States)

    Dunn, Joshua P; Kenedy, Melisha R; Iqbal, Henna; Akins, Darrin R

    2015-03-24

    Like all diderm bacteria studied to date, Borrelia burgdorferi possesses a β-barrel assembly machine (BAM) complex. The bacterial BAM complexes characterized thus far consist of an essential integral outer membrane protein designated BamA and one or more accessory proteins. The accessory proteins are typically lipid-modified proteins anchored to the inner leaflet of the outer membrane through their lipid moieties. We previously identified and characterized the B. burgdorferi BamA protein in detail and more recently identified two lipoproteins encoded by open reading frames bb0324 and bb0028 that associate with the borrelial BamA protein. The role(s) of the BAM accessory lipoproteins in B. burgdorferi is currently unknown. Structural modeling of B. burgdorferi BB0028 revealed a distinct β-propeller fold similar to the known structure for the E. coli BAM accessory lipoprotein BamB. Additionally, the structural model for BB0324 was highly similar to the known structure of BamD, which is consistent with the prior finding that BB0324 contains tetratricopeptide repeat regions similar to other BamD orthologs. Consistent with BB0028 and BB0324 being BAM accessory lipoproteins, mutants lacking expression of each protein were found to exhibit altered membrane permeability and enhanced sensitivity to various antimicrobials. Additionally, BB0028 mutants also exhibited significantly impaired in vitro growth. Finally, immunoprecipitation experiments revealed that BB0028 and BB0324 each interact specifically and independently with BamA to form the BAM complex in B. burgdorferi. Combined structural studies, functional assays, and co-immunoprecipitation experiments confirmed that BB0028 and BB0324 are the respective BamB and BamD orthologs in B. burgdorferi, and are important in membrane integrity and/or outer membrane protein localization. The borrelial BamB and BamD proteins both interact specifically and independently with BamA to form a tripartite BAM complex in B

  2. Antimicrobial Activity of Bee Venom and Melittin against Borrelia burgdorferi.

    Science.gov (United States)

    Socarras, Kayla M; Theophilus, Priyanka A S; Torres, Jason P; Gupta, Khusali; Sapi, Eva

    2017-11-29

    Lyme disease is a tick-borne, multi-systemic disease, caused by the bacterium Borrelia burgdorferi. Though antibiotics are used as a primary treatment, relapse often occurs after the discontinuation of antimicrobial agents. The reason for relapse remains unknown, however previous studies suggest the possible presence of antibiotic resistant Borrelia round bodies, persisters and attached biofilm forms. Thus, there is an urgent need to find antimicrobial agents suitable to eliminate all known forms of B. burgdorferi . In this study, natural antimicrobial agents such as Apis mellifera venom and a known component, melittin, were tested using SYBR Green I/PI, direct cell counting, biofilm assays combined with LIVE/DEAD and atomic force microscopy methods. The obtained results were compared to standalone and combinations of antibiotics such as Doxycycline, Cefoperazone, Daptomycin, which were recently found to be effective against Borrelia persisters. Our findings showed that both bee venom and melittin had significant effects on all the tested forms of B. burgdorferi. In contrast, the control antibiotics when used individually or even in combinations had limited effects on the attached biofilm form. These findings strongly suggest that whole bee venom or melittin could be effective antimicrobial agents for B. burgdorferi; however, further research is necessary to evaluate their effectiveness in vivo, as well as their safe and effective delivery method for their therapeutic use.

  3. Occurrence of multiple infections with different Borrelia burgdorferi genospecies in Danish Ixodes ricinus nymphs

    DEFF Research Database (Denmark)

    Andersen, Jean Vennestrøm; Egholm, H.; Mikkelsen, Per Jensen

    2008-01-01

    The pathogen Borrelia burgdorferi causes Lyme Borreliosis in human and animals world-wide. In Europe the pathogen is transmitted to the host by the vector Ixodes ricinus. The nymph is the primary instar for transmission to humans. We here study the infection rate of five Borrelia genospecies: B...

  4. Borrelia burgdorferi sensu lato in humans in a rural area of Paraná State, Brazil

    Directory of Open Access Journals (Sweden)

    Daniela Dib Gonçalves

    2015-06-01

    Full Text Available This study describes the detection of Borrelia garinii and Borrelia burgdorferi sensu stricto (s.s. in Brazilian individuals using PCR and DNA sequencing. Our results suggest that these species are emerging pathogens in this country, and additional studies are necessary to determine the epidemiological characteristics of this disease in Brazil.

  5. The ecology of Lyme borreliosis risk : interactions between lxodes ricinus, rodents and Borrelia burgdorferi sensu lato

    NARCIS (Netherlands)

    Duijvendijk, van Gilian

    2016-01-01

    The sheep tick (Ixodes ricinus) is widespread throughout Europe and can transmit Borrelia burgdorferi sensu lato (s.l.), which can cause Lyme borreliosis and B. miyamotoi, the agent of Borrelia miyamotoi disease in humans.

  6. Larvae of Ixodes ricinus transmit Borrelia afzelii and B. miyamotoi to vertebrate hosts

    NARCIS (Netherlands)

    van Duijvendijk, Gilian; Coipan, Claudia; Wagemakers, Alex; Fonville, Manoj; Ersöz, Jasmin; Oei, Anneke; Földvári, Gábor; Hovius, Joppe; Takken, Willem; Sprong, Hein

    2016-01-01

    Lyme borreliosis is the most common tick-borne human disease and is caused by Borrelia burgdorferi sensu lato (s.l.). Borrelia miyamotoi, a relapsing fever spirochaete, is transmitted transovarially, whereas this has not been shown for B. burgdorferi (s.l). Therefore, B. burgdorferi (s.l) is

  7. Larvae of Ixodes ricinus transmit Borrelia afzelii and B. miyamotoi to vertebrate hosts

    NARCIS (Netherlands)

    Duijvendijk, van Gilian; Coipan, Claudia; Wagemakers, Alex; Fonville, Manoj; Ersöz, Jasmin; Oei, Anneke; Földvári, Gábor; Hovius, Joppe; Takken, Willem; Sprong, Hein

    2016-01-01

    Background: Lyme borreliosis is the most common tick-borne human disease and is caused by Borrelia burgdorferi sensu lato (s.l.). Borrelia miyamotoi, a relapsing fever spirochaete, is transmitted transovarially, whereas this has not been shown for B. burgdorferi (s.l). Therefore, B. burgdorferi

  8. Preferential protection of Borrelia burgdorferi sensu stricto by a Salp15 homologue in Ixodes ricinus saliva

    NARCIS (Netherlands)

    Hovius, J. W.; Schuijt, T. J.; de Groot, K. A.; Roelofs, J. J. T. H.; Oei, G. A.; Marquart, J. A.; de Beer, R.; van 't Veer, C.; van der Poll, T.; Ramamoorthi, N.; Fikrig, E.; van Dam, A. P.

    2008-01-01

    BACKGROUND: Ixodes ticks are the main vectors for Borrelia burgdorferi sensu lato. In the United States, B. burgdorferi is the sole causative agent of Lyme borreliosis and is transmitted by Ixodes scapularis. In Europe, 3 Borrelia species-B. burgdorferi, B. garinii, and B. afzelii-are prevalent,

  9. The Outer Space Treaty

    Science.gov (United States)

    Johnson, Christopher Daniel

    2018-01-01

    Negotiated at the United Nations and in force since 1967, the Outer Space Treaty has been ratified by over 100 countries and is the most important and foundational source of space law. The treaty, whose full title is "Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies," governs all of humankind's activities in outer space, including activities on other celestial bodies and many activities on Earth related to outer space. All space exploration and human spaceflight, planetary sciences, and commercial uses of space—such as the global telecommunications industry and the use of space technologies such as position, navigation, and timing (PNT), take place against the backdrop of the general regulatory framework established in the Outer Space Treaty. A treaty is an international legal instrument which balances rights and obligations between states, and exists as a kind of mutual contract of shared understandings, rights, and responsibilities between them. Negotiated and drafted during the Cold War era of heightened political tensions, the Outer Space Treaty is largely the product of efforts by the United States and the USSR to agree on certain minimum standards and obligations to govern their competition in "conquering" space. Additionally, the Outer Space Treaty is similar to other treaties, including treaties governing the high seas, international airspace, and the Antarctic, all of which govern the behavior of states outside of their national borders. The treaty is brief in nature and only contains 17 articles, and is not comprehensive in addressing and regulating every possible scenario. The negotiating states knew that the Outer Space Treaty could only establish certain foundational concepts such as freedom of access, state responsibility and liability, non-weaponization of space, the treatment of astronauts in distress, and the prohibition of non-appropriation of

  10. Saturn's outer magnetosphere

    Science.gov (United States)

    Schardt, A. W.; Behannon, K. W.; Carbary, J. F.; Eviatar, A.; Lepping, R. P.; Siscoe, G. L.

    1983-01-01

    Similarities between the Saturnian and terrestrial outer magnetosphere are examined. Saturn, like Earth, has a fully developed magnetic tail, 80 to 100 RS in diameter. One major difference between the two outer magnetospheres is the hydrogen and nitrogen torus produced by Titan. This plasma is, in general, convected in the corotation direction at nearly the rigid corotation speed. Energies of magnetospheric particles extend to above 500 keV. In contrast, interplanetary protons and ions above 2 MeV have free access to the outer magnetosphere to distances well below the Stormer cutoff. This access presumably occurs through the magnetotail. In addition to the H+, H2+, and H3+ ions primarily of local origin, energetic He, C, N, and O ions are found with solar composition. Their flux can be substantially enhanced over that of interplanetary ions at energies of 0.2 to 0.4 MeV/nuc.

  11. Borrelia carolinensis sp. nov., a new (14th) member of the Borrelia burgdorferi Sensu Lato complex from the southeastern region of the United States

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Grubhoffer, Libor; Oliver, J. H., Jr.

    2009-01-01

    Roč. 47, č. 1 (2009), s. 134-141 ISSN 0095-1137 R&D Projects: GA MŠk(CZ) LC06009; GA ČR(CZ) GA524/06/1479 Institutional research plan: CEZ:AV0Z60220518 Keywords : multilocus sequence analysis * B. burgdorferi sl complex * new borrelia species * Borrelia carolinensis Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 4.162, year: 2009

  12. Inner-sphere, outer-sphere and ternary surface complexes: a TRLFS study of the sorption process of europium(III) onto smectite

    International Nuclear Information System (INIS)

    Stumpf, Th.; Fanghaenel, Th.; Bauer, A.; Kim, J.I.

    2002-01-01

    The surface sorption process of Eu(III) onto smectite was investigated by TRLFS in the trace concentration range. With increasing pH the formation of an inner-sphere Eu(III) surface complex was observed. The differences in the spectra and the fluorescence emission lifetimes of the surface sorbed Eu(III) in presence and absence of carbonate indicate the formation of ternary clay/Eu(III)/carbonate complexes /1/. (orig.)

  13. Whole-Genome Sequences of Thirteen Isolates of Borrelia burgdorferi

    Energy Technology Data Exchange (ETDEWEB)

    Schutzer S. E.; Dunn J.; Fraser-Liggett, C. M.; Casjens, S. R.; Qiu, W.-G.; Mongodin, E. F.; Luft, B. J.

    2011-02-01

    Borrelia burgdorferi is a causative agent of Lyme disease in North America and Eurasia. The first complete genome sequence of B. burgdorferi strain 31, available for more than a decade, has assisted research on the pathogenesis of Lyme disease. Because a single genome sequence is not sufficient to understand the relationship between genotypic and geographic variation and disease phenotype, we determined the whole-genome sequences of 13 additional B. burgdorferi isolates that span the range of natural variation. These sequences should allow improved understanding of pathogenesis and provide a foundation for novel detection, diagnosis, and prevention strategies.

  14. Lyme borreliosis: insights into tick- / host-borrelia relations

    Czech Academy of Sciences Publication Activity Database

    Grubhoffer, Libor; Golovchenko, Maryna; Vancová, Marie; Zacharovová, Klára; Rudenko, Natalia; Oliver, J. H., Jr.

    2005-01-01

    Roč. 52, č. 4 (2005), s. 279-294 ISSN 0015-5683 R&D Projects: GA ČR GA524/03/1326; GA ČR GA206/03/1323 Grant - others:National Institutes of Health(US) R37 AI-24899; Science and Technology Collaboration AVCR-NRC Canada(CZ) Z60220518/58-8500 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia spirochetes * ticks * lectins * glycoproteins Subject RIV: EE - Microbiology, Virology Impact factor: 1.138, year: 2005

  15. Long-Lived Glass Mirrors For Outer Space

    Science.gov (United States)

    Bouquet, Frank L.; Maag, Carl R.; Heggen, Philip M.

    1988-01-01

    Paper summarizes available knowledge about glass mirrors for use in outer space. Strengths and weaknesses of various types of first and second reflective surfaces identified. Second-surface glass mirrors used in outer space designed to different criteria more stringent for terrestrial mirrors. Protons, electrons, cosmic rays, meteorites, and orbiting space debris affect longevities of components. Contamination also factor in space.

  16. Relapsing fever causative agent in Southern Iran is a closely related species to East African borreliae.

    Science.gov (United States)

    Naddaf, Saied Reza; Ghazinezhad, Behnaz; Kazemirad, Elham; Cutler, Sally Jane

    2017-10-01

    We obtained two blood samples from relapsing fever patients residing in Jask County, Hormozgan Province, southern Iran in 2013. Sequencing of a partial fragment of glpQ from two samples, and further characterization of one of them by analyzing flaB gene, and 16S-23S spacer (IGS) revealed the greatest sequence identity with East African borreliae, Borrelia recurrentis, and Borrelia duttonii, and Borrelia microti from Iran. Phylogenetic analyses of glpQ, flaB, and concatenated sequences (glpQ, flab, and IGS) clustered these sequences amongst East African Relapsing fever borreliae and B. microti from Iran. However, the more discriminatory IGS disclosed a unique 8-bp signature (CAGCCTAA) separating these from B. microti and indeed other relapsing fever borreliae. In southern Iran, relapsing fever cases are mostly from localities in which O. erraticus ticks, the notorious vector of B. microti, prevail. There are chances that this argasid tick serves as a host and vector of several closely related species or ecotypes including the one we identified in the present study. The distribution of this Borrelia species remains to be elucidated, but it is assumed to be endemic to lowland areas of the Hormozgan Province, as well as Sistan va Baluchistan in the southeast and South Khorasan (in Persian: Khorasan-e Jonobi) in the east of Iran. Copyright © 2017 Elsevier GmbH. All rights reserved.

  17. TPS for Outer Planets

    Science.gov (United States)

    Venkatapathy, Ethiraj; Ellerby, D.; Gage, P.; Gasch, M.; Hwang, H.; Prabhu, D.; Stackpoole, M.; Wercinski, Paul

    2018-01-01

    This invited talk will provide an assessment of the TPS needs for Outer Planet In-situ missions to destinations with atmosphere. The talk will outline the drivers for TPS from destination, science, mission architecture and entry environment. An assessment of the readiness of the TPS, both currently available and under development, for Saturn, Titan, Uranus and Neptune are provided. The challenges related to sustainability of the TPS for future missions are discussed.

  18. Combined natural convection and surface radiation in the annular region between a volumetrically heated inner tube and a finite conducting outer tube

    International Nuclear Information System (INIS)

    Gianoulakis, S.; Klein, D.E.

    1993-01-01

    Buoyancy-driven natural-convection heat transfer in enclosures has been the subject of considerable research with applications to electronic packaging, solar collectors, and shipping containers for spent nuclear fuel. A numerical study has been carried out to predict combined natural-convection and radiation heat transfer in the annular region between concentric tubes. The inner tube was volumetrically heated. Both tubes were of finite conductance. The surfaces of the annular region were diffuse and gray. The gas in the annulus was assumed to be nonparticipating. A newly developed hybrid finite element finite difference method was used for the study. This method combines finite element discretization of geometries with finite difference discretized solution procedures for the governing differential equations. This study examined the effects of surface radiative properties and material conductivities on the temperature and velocity fields and on local heat transfer rates. Fluid Raleigh numbers ranging from 10 3 to 10 7 , ratios of solid to fluid region thermal conductivities ranging from 10 to 10 4 , and surface total hemispherical emissivities ranging from 0.0 to 1.0 were examined in this study. It was found that the heat transfer across the annulus was dominated by conduction and radiation for the lower Raleigh number flows. As the fluid Raleigh number increased, convection became a primary mode of heat transfer. As the surface emissivity was increased in the annulus, the average Nusselt number on the inner tube surface decreased

  19. Outer Continental Shelf Lands Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data represents geographic terms used within the Outer Continental Shelf Lands Act (OCSLA or Act). The Act defines the United States outer continental shelf...

  20. Chemical design of pH-sensitive nanovalves on the outer surface of mesoporous silicas for controlled storage and release of aromatic amino acid

    International Nuclear Information System (INIS)

    Roik, N.V.; Belyakova, L.A.

    2014-01-01

    Mesoporous silicas with hexagonally arranged pore channels were synthesized in water–ethanol-ammonia solution using cetyltrimethylammonium bromide as template. Directed modification of silica surface with N-[N′-(N′-phenyl)-2-aminophenyl]-3-aminopropyl groups was realized by postsynthetic activation of halogenoalkylsilicas, which have surface uniformly or selectively distributed 3-chloropropyl groups, with 2-aminodiphenylamine in the liquid phase. Chemical composition of silica materials was estimated by IR spectroscopy and chemical analysis of the surface products of reactions. Characteristics of porous structure of MCM-41-type silicas were determined from X-ray and low-temperature nitrogen ad-desorption measurements. Release ability of synthesized silica carriers was established on encapsulation of 4-aminobenzoic acid in pore channels and subsequent delivery at pH=6.86 and pH=1.00. It was found that N-[N′-(N′-phenyl)-2-aminophenyl]-3-aminopropyl groups block pore entrances at neutral pH preventing 4-aminobenzoic acid release. At pH=1.00 repulsion of positively charged surface aromatic amino groups localized near pore orifices provides unhindered liberation of aromatic amino acid from mesoporous channels. - Graphical abstract: Blocking of pores with N-[N′-(N′-phenyl)-2-aminophenyl]-3-aminopropyl groups at pH=6.86 for storage of ABA and opening of pore entrances at pH=1.00 for unhindered ABA liberation. - Highlights: • Modification of MCM-41 with N-[N′-(N′-phenyl)-2-aminophenyl]-3-aminopropyl groups. • Study of release ability of synthesized silica carriers in relation to amino acid. • Controlled blocking and opening of pores by amino groups at pH change were performed. • Retention of amino acid at pH=6.86 and its liberation at pH=1.00 was proved

  1. Persistent Borrelia Infection in Patients with Ongoing Symptoms of Lyme Disease

    Directory of Open Access Journals (Sweden)

    Marianne J. Middelveen

    2018-04-01

    Full Text Available Introduction: Lyme disease is a tickborne illness that generates controversy among medical providers and researchers. One of the key topics of debate is the existence of persistent infection with the Lyme spirochete, Borrelia burgdorferi, in patients who have been treated with recommended doses of antibiotics yet remain symptomatic. Persistent spirochetal infection despite antibiotic therapy has recently been demonstrated in non-human primates. We present evidence of persistent Borrelia infection despite antibiotic therapy in patients with ongoing Lyme disease symptoms. Methods: In this pilot study, culture of body fluids and tissues was performed in a randomly selected group of 12 patients with persistent Lyme disease symptoms who had been treated or who were being treated with antibiotics. Cultures were also performed on a group of ten control subjects without Lyme disease. The cultures were subjected to corroborative microscopic, histopathological and molecular testing for Borrelia organisms in four independent laboratories in a blinded manner. Results: Motile spirochetes identified histopathologically as Borrelia were detected in culture specimens, and these spirochetes were genetically identified as Borrelia burgdorferi by three distinct polymerase chain reaction (PCR-based approaches. Spirochetes identified as Borrelia burgdorferi were cultured from the blood of seven subjects, from the genital secretions of ten subjects, and from a skin lesion of one subject. Cultures from control subjects without Lyme disease were negative for Borrelia using these methods. Conclusions: Using multiple corroborative detection methods, we showed that patients with persistent Lyme disease symptoms may have ongoing spirochetal infection despite antibiotic treatment, similar to findings in non-human primates. The optimal treatment for persistent Borrelia infection remains to be determined.

  2. Persistent Borrelia Infection in Patients with Ongoing Symptoms of Lyme Disease.

    Science.gov (United States)

    Middelveen, Marianne J; Sapi, Eva; Burke, Jennie; Filush, Katherine R; Franco, Agustin; Fesler, Melissa C; Stricker, Raphael B

    2018-04-14

    Lyme disease is a tickborne illness that generates controversy among medical providers and researchers. One of the key topics of debate is the existence of persistent infection with the Lyme spirochete, Borrelia burgdorferi , in patients who have been treated with recommended doses of antibiotics yet remain symptomatic. Persistent spirochetal infection despite antibiotic therapy has recently been demonstrated in non-human primates. We present evidence of persistent Borrelia infection despite antibiotic therapy in patients with ongoing Lyme disease symptoms. In this pilot study, culture of body fluids and tissues was performed in a randomly selected group of 12 patients with persistent Lyme disease symptoms who had been treated or who were being treated with antibiotics. Cultures were also performed on a group of ten control subjects without Lyme disease. The cultures were subjected to corroborative microscopic, histopathological and molecular testing for Borrelia organisms in four independent laboratories in a blinded manner. Motile spirochetes identified histopathologically as Borrelia were detected in culture specimens, and these spirochetes were genetically identified as Borrelia burgdorferi by three distinct polymerase chain reaction (PCR)-based approaches. Spirochetes identified as Borrelia burgdorferi were cultured from the blood of seven subjects, from the genital secretions of ten subjects, and from a skin lesion of one subject. Cultures from control subjects without Lyme disease were negative for Borrelia using these methods. Using multiple corroborative detection methods, we showed that patients with persistent Lyme disease symptoms may have ongoing spirochetal infection despite antibiotic treatment, similar to findings in non-human primates. The optimal treatment for persistent Borrelia infection remains to be determined.

  3. Management of outer space

    Science.gov (United States)

    Perek, Lubos

    1993-10-01

    Various aspects of space-environment management are discussed. Attention is called to the fact that, while space radio communications are already under an adequate management by the International Communications Union, the use of nuclear power sources is regulated by the recently adopted set of principles, and space debris will be discussed in the near future at the UN COPUOS, other aspects of management of outer space received little or no attention of the international community. These include the competency of crews and technical equipment of spacecraft launched by newcomers to space exploration; monitoring of locations and motions of space objects (now in national hands), with relevant data made accessible through a computer network; and the requirement to use space only for beneficial purposes and not for promoting narrow and debatable interests damaging the outer space environment and impeding on astronomical observations. It is suggested that some of these tasks would be best performed by an international space agency within the UN system of organizations.

  4. Differentiated THP-1 Cells Exposed to Pathogenic and Nonpathogenic Borrelia Species Demonstrate Minimal Differences in Production of Four Inflammatory Cytokines.

    Science.gov (United States)

    Stokes, John V; Moraru, Gail M; McIntosh, Chelsea; Kummari, Evangel; Rausch, Keiko; Varela-Stokes, Andrea S

    2016-11-01

    Tick-borne borreliae include Lyme disease and relapsing fever agents, and they are transmitted primarily by ixodid (hard) and argasid (soft) tick vectors, respectively. Tick-host interactions during feeding are complex, with host immune responses influenced by biological differences in tick feeding and individual differences within and between host species. One of the first encounters for spirochetes entering vertebrate host skin is with local antigen-presenting cells, regardless of whether the tick-associated Borrelia sp. is pathogenic. In this study, we performed a basic comparison of cytokine responses in THP-1-derived macrophages after exposure to selected borreliae, including a nonpathogen. By using THP-1 cells, differentiated to macrophages, we eliminated variations in host response and reduced the system to an in vitro model to evaluate the extent to which the Borrelia spp. influence cytokine production. Differentiated THP-1 cells were exposed to four Borrelia spp., Borrelia hermsii (DAH), Borrelia burgdorferi (B31), B. burgdorferi (NC-2), or Borrelia lonestari (LS-1), or lipopolysaccharides (LPS) (activated) or media (no treatment) controls. Intracellular and secreted interferon (IFN)-γ, interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were measured using flow cytometric and Luminex-based assays, respectively, at 6, 24, and 48 h postexposure time points. Using a general linear model ANOVA for each cytokine, treatment (all Borrelia spp. and LPS compared to no treatment) had a significant effect on secreted TNF-α only. Time point had a significant effect on intracellular IFN-γ, TNF-α and IL-6. However, we did not see significant differences in selected cytokines among Borrelia spp. Thus, in this model, we were unable to distinguish pathogenic from nonpathogenic borreliae using the limited array of selected cytokines. While unique immune profiles may be detectable in an in vitro model and may reveal predictors for pathogenicity in borreliae

  5. Two ways of experimental infection of Ixodes ricinus ticks (Acari: Ixodidae) with spirochetes of Borrelia burgdorferi sensu lato complex

    Czech Academy of Sciences Publication Activity Database

    Fišerová, Lenka; Černá, Kateřina; Horká, Helena; Kopecký, Jan

    2008-01-01

    Roč. 55, č. 2 (2008), s. 150-154 ISSN 0015-5683 R&D Projects: GA ČR GA524/05/0811; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lyme disease spirochete * Borrelia burgdorferi * Borrelia baronii * Borrelia afzelii * tick * Ixodes ricinus Subject RIV: EC - Immunology Impact factor: 1.307, year: 2008

  6. Zinc is the metal cofactor of Borrelia burgdorferi peptide deformylase.

    Science.gov (United States)

    Nguyen, Kiet T; Wu, Jen-Chieh; Boylan, Julie A; Gherardini, Frank C; Pei, Dehua

    2007-12-15

    Peptide deformylase (PDF, E.C. 3.5.1.88) catalyzes the removal of N-terminal formyl groups from nascent ribosome-synthesized polypeptides. PDF contains a catalytically essential divalent metal ion, which is tetrahedrally coordinated by three protein ligands (His, His, and Cys) and a water molecule. Previous studies revealed that the metal cofactor is a Fe2+ ion in Escherichia coli and many other bacterial PDFs. In this work, we found that PDFs from two iron-deficient bacteria, Borrelia burgdorferi and Lactobacillus plantarum, are stable and highly active under aerobic conditions. The native B. burgdorferi PDF (BbPDF) was purified 1200-fold and metal analysis revealed that it contains approximately 1.1 Zn2+ ion/polypeptide but no iron. Our studies suggest that PDF utilizes different metal ions in different organisms. These data have important implications in designing PDF inhibitors and should help address some of the unresolved issues regarding PDF structure and catalytic function.

  7. Borrelia burgdorferi-specific IgA in Lyme Disease

    Directory of Open Access Journals (Sweden)

    Christina D'Arco

    2017-05-01

    Full Text Available The laboratory diagnosis of Lyme disease is currently dependent on the detection of IgM and IgG antibodies against Borrelia burgdorferi, the causative agent of the disease. The significance of serum IgA against B. burgdorferi remains unclear. The production of intrathecal IgA has been noted in patients with the late Lyme disease manifestation, neuroborreliosis, but production of antigen-specific IgA during early disease has not been evaluated. In the current study, we assessed serum IgA binding to the B. burgdorferi peptide antigens, C6, the target of the FDA-cleared C6 EIA, and FlaB(211-223-modVlsE(275-291, a peptide containing a Borrelia flagellin epitope linked to a modified VlsE sequence, in patients with early and late Lyme disease. Specific IgA was detected in 59 of 152 serum samples (38.8% from early Lyme disease patients. Approximately 50% of early Lyme disease patients who were seropositive for peptide-specific IgM and/or IgG were also seropositive for peptide-specific IgA. In a subpopulation of patients, high peptide-specific IgA could be correlated with disseminated disease, defined as multiple erythema migrans lesions, and neurological disease complications. These results suggest that there may be an association between elevated levels of antigen-specific IgA and particular disease manifestations in some patients with early Lyme disease.

  8. Borrelia burgdorferi-specific IgA in Lyme Disease.

    Science.gov (United States)

    D'Arco, Christina; Dattwyler, Raymond J; Arnaboldi, Paul M

    2017-05-01

    The laboratory diagnosis of Lyme disease is currently dependent on the detection of IgM and IgG antibodies against Borrelia burgdorferi, the causative agent of the disease. The significance of serum IgA against B. burgdorferi remains unclear. The production of intrathecal IgA has been noted in patients with the late Lyme disease manifestation, neuroborreliosis, but production of antigen-specific IgA during early disease has not been evaluated. In the current study, we assessed serum IgA binding to the B. burgdorferi peptide antigens, C6, the target of the FDA-cleared C6 EIA, and FlaB(211-223)-modVlsE(275-291), a peptide containing a Borrelia flagellin epitope linked to a modified VlsE sequence, in patients with early and late Lyme disease. Specific IgA was detected in 59 of 152 serum samples (38.8%) from early Lyme disease patients. Approximately 50% of early Lyme disease patients who were seropositive for peptide-specific IgM and/or IgG were also seropositive for peptide-specific IgA. In a subpopulation of patients, high peptide-specific IgA could be correlated with disseminated disease, defined as multiple erythema migrans lesions, and neurological disease complications. These results suggest that there may be an association between elevated levels of antigen-specific IgA and particular disease manifestations in some patients with early Lyme disease. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Borrelia host adaptation Regulator (BadR) regulates rpoS to modulate host adaptation and virulence factors in Borrelia burgdorferi

    OpenAIRE

    Miller, Christine L.; Rajasekhar Karna, S. L.; Seshu, J.

    2013-01-01

    The RpoS transcription factor of Borrelia burgdorferi is a “gatekeeper” because it activates genes required for spirochetes to transition from tick to vertebrate hosts. However, it remains unknown how RpoS becomes repressed to allow the spirochetes to transition back from the vertebrate host to the tick vector. Here we show that a putative carbohydrate-responsive regulatory protein, designated BadR (Borrelia host adaptation Regulator), is a transcriptional repressor of rpoS. BadR levels are e...

  10. Outer atmospheric research

    International Nuclear Information System (INIS)

    Anderson, J.L.

    1988-01-01

    The region above the earth from about 90 km to 150 km is a major part of the upper or outer atmosphere. It is relatively unexplored, being too high for balloons or aircraft and too low for persistent orbiting spacecraft. However, the concept of a tethered subsatellite, deployed downward from an orbiting, more massive craft such as the Space Shuttle, opens the possibility of a research capability that could provide global mapping of this region. The need for research in this thick spherical shell above the earth falls into two major categories: (1) scientific data for understanding and modeling the global atmosphere and thereby determining its role in the earth system, and (2) engineering data for the design of future aerospace vehicles that will operate there. This paper presents an overview and synthesis of the currently perceived research needs and the state-of-the-art of the proposed tethered research capability. 16 references

  11. Geographical and genospecies distribution of Borrelia burgdorferi sensu lato DNA detected in humans in the USA.

    Science.gov (United States)

    Clark, Kerry L; Leydet, Brian F; Threlkeld, Clifford

    2014-05-01

    The present study investigated the cause of illness in human patients primarily in the southern USA with suspected Lyme disease based on erythema migrans-like skin lesions and/or symptoms consistent with early localized or late disseminated Lyme borreliosis. The study also included some patients from other states throughout the USA. Several PCR assays specific for either members of the genus Borrelia or only for Lyme group Borrelia spp. (Borrelia burgdorferi sensu lato), and DNA sequence analysis, were used to identify Borrelia spp. DNA in blood and skin biopsy samples from human patients. B. burgdorferi sensu lato DNA was found in both blood and skin biopsy samples from patients residing in the southern states and elsewhere in the USA, but no evidence of DNA from other Borrelia spp. was detected. Based on phylogenetic analysis of partial flagellin (flaB) gene sequences, strains that clustered separately with B. burgdorferi sensu stricto, Borrelia americana or Borrelia andersonii were associated with Lyme disease-like signs and symptoms in patients from the southern states, as well as from some other areas of the country. Strains most similar to B. burgdorferi sensu stricto and B. americana were found most commonly and appeared to be widely distributed among patients residing throughout the USA. The study findings suggest that human cases of Lyme disease in the southern USA may be more common than previously recognized and may also be caused by more than one species of B. burgdorferi sensu lato. This study provides further evidence that B. burgdorferi sensu stricto is not the only species associated with signs and/or symptoms consistent with Lyme borreliosis in the USA.

  12. Molecular Typing of Borrelia burgdorferi Sensu Lato by Randomly Amplified Polymorphic DNA Fingerprinting Analysis

    Science.gov (United States)

    Wang, Guiqing; van Dam, Alje P.; Spanjaard, Lodewijk; Dankert, Jacob

    1998-01-01

    To study whether pathogenic clusters of Borrelia burgdorferi sensu lato strains occur, we typed 136 isolates, cultured from specimens from patients (n = 49) with various clinical entities and from ticks (n = 83) or dogs (n = 4) from different geographic regions, by randomly amplified polymorphic DNA (RAPD) fingerprinting with four arbitrary primers. The RAPD patterns were reproducible up to the 95% similarity level as shown in duplicate experiments. In these experiments the purified DNAs prepared on different days, from different colonies, and after various passages were used as templates. With an intergroup difference of 55%, the 136 strains could be divided into seven genetic clusters. Six clusters comprised and corresponded to the established species B. burgdorferi sensu stricto (n = 23), Borrelia garinii (n = 39), Borrelia afzelii (n = 59), Borrelia japonica (n = 1), Borrelia valaisiana (n = 12), and genomic group DN127 (n = 1). One strain from a patient with erythema migrans (EM) did not belong to any of the species or genomic groups known up to now. The RAPD types of B. burgdorferi sensu stricto, B. garinii, and B. afzelii isolates, which may give rise to human Lyme borreliosis (LB), were associated with their geographic origins. A high degree of genetic diversity was observed among the 39 B. garinii strains, and six subgroups could be recognized. One of these comprised eight isolates from patients with disseminated LB only and no tick isolates. B. afzelii strains from patients with EM or acrodermatitis chronica atrophicans were not clustered in particular branches. Our study showed that RAPD analysis is a powerful tool for discriminating different Borrelia species as well as Borrelia isolates within species. PMID:9508310

  13. Genetic variation of the Borrelia burgdorferi gene vlsE involves cassette-specific, segmental gene conversion.

    Science.gov (United States)

    Zhang, J R; Norris, S J

    1998-08-01

    The Lyme disease spirochete Borrelia burgdorferi possesses 15 silent vls cassettes and a vls expression site (vlsE) encoding a surface-exposed lipoprotein. Segments of the silent vls cassettes have been shown to recombine with the vlsE cassette region in the mammalian host, resulting in combinatorial antigenic variation. Despite promiscuous recombination within the vlsE cassette region, the 5' and 3' coding sequences of vlsE that flank the cassette region are not subject to sequence variation during these recombination events. The segments of the silent vls cassettes recombine in the vlsE cassette region through a unidirectional process such that the sequence and organization of the silent vls loci are not affected. As a result of recombination, the previously expressed segments are replaced by incoming segments and apparently degraded. These results provide evidence for a gene conversion mechanism in VlsE antigenic variation.

  14. Divergence of Borrelia burgdorferi sensu lato spirochetes could be driven by the host: diversity of Borrelia strains isolated from ticks feeding on a single bird

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Belfiore, N. M.; Grubhoffer, Libor; Oliver, J. H., Jr.

    2014-01-01

    Roč. 7, JAN 2014 (2014), s. 4 ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : Borrelia burgdorferi sensu lato * Ixodes minor * bird migration * bird reservoir host * multilocus sequence analysis * multilocus sequence typing * recombinant genotypes * Southeastern United States Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.430, year: 2014

  15. Association of Borrelia and Rickettsia spp. and bacterial loads in Ixodes ricinus ticks.

    Science.gov (United States)

    Raulf, Marie-Kristin; Jordan, Daniela; Fingerle, Volker; Strube, Christina

    2018-01-01

    In recent years, awareness of coinfections has increased as synergistic or antagonistic effects on interacting bacteria have been observed. To date, several reports on coinfections of ticks with Rickettsia and Borrelia spp. are available. However, associations are rarely described and studies are based on rather low sample sizes. In the present study, coinfections of Ixodes ricinus with these pathogens were investigated by determining their association in a meta-analysis. A total of 5079 tick samples examined for Rickettsia and Borrelia spp. via probe-based quantitative real-time PCR in previous prevalence studies or as submitted diagnostic material were included. In Borrelia-positive ticks, genospecies were determined by Reverse Line Blot. Determination of bacterial loads resulted in an increase between developmental tick stages with highest mean bacterial loads in female ticks (7.96×10 4 in Borrelia single-infected, 4.87×10 5 in Rickettsia single-infected and 3.22×10 5 in Borrelia-Rickettsia coinfected females). The determined Borrelia-Rickettsia tick coinfection rate was 12.3% (626/5079) with a significant difference to the expected coinfection rate of 9.0% (457/5079). A significant slight association as well as correlation between Borrelia and Rickettsia were determined. In addition, a significant interrelation of the bacterial load in coinfected ticks was shown. At the level of Borrelia genospecies, significant weak associations with Rickettsia spp. were detected for B. afzelii, B. garinii/bavariensis, B. valaisiana and B. lusitaniae. The positive association provides evidence for interactions between Borrelia and Rickettsia spp. in the tick vector, presumably resulting in higher bacterial replication rates in the tick vector and possibly the reservoir host. However, coinfection may impact the vector negatively as indicated by an absent increase in coinfection rates from nymphs to adults. Future studies are needed to investigate the underlying mechanisms of

  16. Convective heat transport of high-pressure flows inside active, thick walled-tubes with isothermal outer surfaces: usage of Nusselt correlation equations for an inactive, thin walled-tube

    Energy Technology Data Exchange (ETDEWEB)

    Campo, Antonio [Idaho State Univ., Nuclear Engineering Dept., Pocatello, ID (United States); Sanchez, Alejo [Universidad de los Andes, Depto. de Ingenieria Mecanica, Merida (Venezuela)

    1998-03-01

    A semi-analytical analysis was conducted for the prediction of the mean bulk- and interface temperatures of gaseous and liquid fluids moving laminarly at high pressures inside thick-walled metallic tubes. The outer surfaces of the tubes are isothermal. The central goal of this article is to critically examine the thermal response of this kind of in-tube flows utilizing two versions of the 1-D lumped model: one is differential-numerical while the other is differential-algebraic. For the former, the local Nusselt number characterizing an inactive, isothermal tube was taken from correlation equations reported in the heat transfer literature. For the latter, a streamwise-mean Nusselt number associated with an active, isothermal tube was taken from standard correlation equations that appear in text-books on basic heat transfer. For the two different versions of the 1-D lumped model tested, the computed results consistently demonstrate that the differential-algebraic, provides accurate estimates of both the mean bulk- and the interface temperatures when compared with those temperature results computed with formal 2-D differential models. (author)

  17. Isolation of live Borrelia burgdorferi sensu lato spirochaetes from patients with undefined disorders and symptoms not typical for Lyme borreliosis

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Vancová, Marie; Clark, K.; Grubhoffer, Libor; Oliver, J. H., Jr.

    2016-01-01

    Roč. 22, č. 3 (2016), 267.e9-267.e15 ISSN 1198-743X EU Projects: European Commission(XE) 278976 - ANTIGONE Institutional support: RVO:60077344 Keywords : antibiotic treatment * live Borrelia burgdorferi * live Borrelia bissettii * Lyme borreliosis * recovery of live spirochaetes Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 5.292, year: 2016

  18. Identification of Borrelia burgdorferi genospecies isolated from Ixodes ricinus ticks in the South Moravian region of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Bonczek, Ondřej; Žákovská, A.; Vargová, L.; Šerý, Omar

    2015-01-01

    Roč. 22, č. 4 (2015), s. 642-646 ISSN 1232-1966 Institutional support: RVO:67985904 Keywords : Borrelia burgdorferi s. I. * Borrelia spielmanii * Ixodes ricinus Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.895, year: 2015

  19. Outer Solar System Nomenclature

    National Research Council Canada - National Science Library

    Owen, Tobias C

    2000-01-01

    The work to be carried out on the subject grant during the next funding period will center on names needed for surface features on the Galilean satellites of Jupiter, names for the newly discovered...

  20. Will Outer Tropical Cyclone Size Change due to Anthropogenic Warming?

    Science.gov (United States)

    Schenkel, B. A.; Lin, N.; Chavas, D. R.; Vecchi, G. A.; Knutson, T. R.; Oppenheimer, M.

    2017-12-01

    Prior research has shown significant interbasin and intrabasin variability in outer tropical cyclone (TC) size. Moreover, outer TC size has even been shown to vary substantially over the lifetime of the majority of TCs. However, the factors responsible for both setting initial outer TC size and determining its evolution throughout the TC lifetime remain uncertain. Given these gaps in our physical understanding, there remains uncertainty in how outer TC size will change, if at all, due to anthropogenic warming. The present study seeks to quantify whether outer TC size will change significantly in response to anthropogenic warming using data from a high-resolution global climate model and a regional hurricane model. Similar to prior work, the outer TC size metric used in this study is the radius in which the azimuthal-mean surface azimuthal wind equals 8 m/s. The initial results from the high-resolution global climate model data suggest that the distribution of outer TC size shifts significantly towards larger values in each global TC basin during future climates, as revealed by 1) statistically significant increase of the median outer TC size by 5-10% (p<0.05) according to a 1,000-sample bootstrap resampling approach with replacement and 2) statistically significant differences between distributions of outer TC size from current and future climate simulations as shown using two-sample Kolmogorov Smirnov testing (p<<0.01). Additional analysis of the high-resolution global climate model data reveals that outer TC size does not uniformly increase within each basin in future climates, but rather shows substantial locational dependence. Future work will incorporate the regional mesoscale hurricane model data to help focus on identifying the source of the spatial variability in outer TC size increases within each basin during future climates and, more importantly, why outer TC size changes in response to anthropogenic warming.

  1. Proteome Analysis of Borrelia burgdorferi Response to Environmental Change

    Energy Technology Data Exchange (ETDEWEB)

    Angel, Thomas E.; Luft, Benjamin J.; Yang, Xiaohua; Nicora, Carrie D.; Camp, David G.; Jacobs, Jon M.; Smith, Richard D.

    2010-11-02

    We examined global changes in protein expression in the B31 strain of Borrelia burgdorferi, in response to two environmental cues (pH and temperature) chosen for their reported similarity to those encountered at different stages of the organism’s life cycle. Multidimensional nano-liquid chromatographic separations coupled with tandem mass spectrometry were used to examine the array of proteins (i.e., the proteome) of B. burgdorferi for different pH and temperature culture conditions. Changes in pH and temperature elicited in vitro adaptations of this spirochete known to cause Lyme disease and led to alterations in protein expression that are associated with increased microbial pathogenesis. We identified 1031 proteins that represent 59% of the annotated genome of B. burgdorferi and elucidated a core proteome of 414 proteins that were present in all environmental conditions investigated. Observed changes in protein abundances indicated varied replicon usage, as well as proteome functional distributions between the in vitro cell culture conditions. Surprisingly, the pH and temperature conditions that mimicked B. burgdorferi residing in the gut of a fed tick showed a marked reduction in protein diversity. Additionally, the results provide us with leading candidates for exploring how B. burgdorferi adapts to and is able to survive in a wide variety of environmental conditions and lay a foundation for planned in situ studies of B. burgdorferi isolated from the tick midgut and infected animals.

  2. Borrelia spirochetes in Russia: Genospecies differentiation by real-time PCR.

    Science.gov (United States)

    Mukhacheva, T A; Kovalev, S Y

    2014-10-01

    Spirochetes of the Borrelia burgdorferi sensu lato complex are the causative agent of Lyme borreliosis which is widespread in Russia. Nowadays, three clinically important B. burgdorferi s.l. genospecies, B. afzelii, B. garinii, B. bavariensis sp. nov., can be found in Russia, as well as B. miyamotoi, which belongs to the tick-borne relapsing fever group of spirochetes. Several techniques have been developed to differentiate Borrelia genospecies. However, most of them do not allow detection of all of these genospecies simultaneously. Also, no method based on the RT-PCR TaqMan approach has been proposed to differentiate the genetically closely related species B. bavariensis and B. garinii. In the present paper, we investigated two species of ticks, I. persulcatus and I. pavlovskyi (1343 and 92 adults, respectively). Two sets of primers and probes for RT-PCR, with uvrA, glpQ and nifS genes as targets, were designed to detect four Borrelia genospecies in positive samples. The average prevalence of Borrelia sp. was about 40%, with B. afzelii as the most prevalent genospecies. Mixed infections of B. bavariensis and B. garinii were found to be extremely rare. While B. bavariensis was predominant in I. persulcatus, I. pavlovskyi ticks were infected exclusively by B. garinii. The proposed technique proved to be efficient in selection of individual Borrelia species for further genetic analysis, in particular, for multilocus sequence typing. Also, it could be applied for the differentiation of Borrelia genospecies in clinical material. Copyright © 2014 Elsevier GmbH. All rights reserved.

  3. Infection of Ixodes ricinus by Borrelia burgdorferi sensu lato in peri-urban forests of France.

    Directory of Open Access Journals (Sweden)

    Axelle Marchant

    Full Text Available Lyme borreliosis is the most common tick-borne disease in the northern hemisphere. In Europe, it is transmitted by Ixodes ticks that carry bacteria belonging to the Borrelia burgdorferi sensu lato complex. The objective of this work was to explore eco-epidemiological factors of Lyme borreliosis in peri-urban forests of France (Sénart, Notre-Dame and Rambouillet. We investigated whether the introduction of Tamias sibiricus in Sénart could alter the density of infected ticks. Moreover, the density and tick infection were investigated according to the tree species found in various patches of Sénart forest. For this purpose, ticks were sampled during 3 years. In the Sénart forest, the density of nymph and adult ticks showed no significant difference between 2008, 2009 and 2011. The nymph density varied significantly as a function of the month of collection. Regarding the nymphs, a higher rate of infection and infected density were found in 2009. Plots with chipmunks (C presented a lower density of both nymphs and adult ticks than plots without chipmunks (NC did. A higher rate of infection of nymphs with Borrelia was seen in C plots. The prevalence of the various species of Borrelia was also found to vary between C and NC plots with the year of the collect. The presence of chestnut trees positively influenced the density of both nymphs and adults. The infected nymph density showed a significant difference depending on the peri-urban forest studied, Sénart being higher than Rambouillet. The prevalence of Borrelia species also differed between the various forests studied. Concerning the putative role that Tamias sibiricus may play in the transmission of Borrelia, our results suggest that its presence is correlated with a higher rate of infection of questing ticks by Borrelia genospecies and if its population increases, it could play a significant role in the risk of transmission of Lyme borreliosis.

  4. Cryovolcanism in the outer solar system

    Science.gov (United States)

    Geissler, Paul E.

    2015-01-01

    Cryovolcanism is defined as the extrusion of liquids and vapors of materials that would be frozen solid at the planetary surface temperatures of the icy bodies of the outer solar system. Active cryovolcanism is now known to occur on Saturn's moon Enceladus and on Neptune's moon Triton and is suspected on Jupiter's moon Europa, while evidence for past cryovolcanic activity is widespread throughout the outer solar system. This chapter examines the mechanisms and manifestations of cryovolcanism, beginning with a review of the materials that make up these unusual ‘‘magmas’’ and the means by which they might erupt and concluding with a volcanologist's tour of the farthest reaches of the solar system.

  5. First insights in the variability of Borrelia recurrentis genomes.

    Directory of Open Access Journals (Sweden)

    Durdica Marosevic

    2017-09-01

    Full Text Available Borrelia recurrentis is the causative agent of louse-borne relapsing fever, endemic to the Horn of Africa. New attention was raised in Europe, with the highest number of cases (n = 45 reported among migrants in 2015 in Germany and sporadically from other European countries. So far only one genome was sequenced, hindering the development of specific molecular diagnostic and typing tools. Here we report on modified culture conditions for B. recurrentis and the intraspecies genome variability of six isolates isolated and cultured in different years in order to explore the possibility to identify new targets for typing and examine the molecular epidemiology of the pathogen.Two historical isolates from Ethiopia and four isolates from migrants from Somalia (n = 3 and Ethiopia (n = 1 obtained in 2015 were cultured in MPK-medium supplemented with 50% foetal calf serum. Whole DNA was sequenced using Illumina MiSeq technology and analysed using the CLC Genomics Workbench and SPAdes de novo assembler. Compared to the reference B. recurrentis A1 29-38 SNPs were identified in the genome distributed on the chromosome and plasmids. In addition to that, plasmids of differing length, compared to the available reference genome were identified.The observed low genetic variability of B. recurrentis isolates is possibly due to the adaptation to a very conserved vector-host (louse-human cycle, or influenced by the fastidious nature of the pathogen and their resistance to in vitro growth. Nevertheless, isolates obtained in 2015 were bearing the same chromosomal SNPs and could be distinguished from the historical isolates by means of whole genome sequencing, but not hitherto used typing methods. This is the first study examining the molecular epidemiology of B. recurrentis and provides the necessary background for the development of better diagnostic tools.

  6. Babesia microti, human babesiosis, and Borrelia burgdorferi in Connecticut.

    Science.gov (United States)

    Anderson, J F; Mintz, E D; Gadbaw, J J; Magnarelli, L A

    1991-12-01

    Babesia microti was isolated from a white-footed mouse (Peromyscus leucopus) that was captured in southeastern Connecticut in 1988, when the first human case of babesiosis acquired in Connecticut was recognized. To date, 13 cases of babesiosis have been reported in Connecticut, the largest number of human cases reported on the mainland United States. Two of nine patients quiried remembered a prior tick bite. Since Babesia parasites are known to be vectored only by ticks, we surmise that 12 of these infections were acquired via tick bites; 1 was obtained by blood transfusion (the patient was 46 years of age) from an endemically infected donor. The ages of the patients with tick-acquired babesiosis ranged from 61 to 95 years. Two patients died with active infections, and one patient died from chronic obstructive pulmonary disease soon after treatment with clindamycin and quinine. Indirect fluorescent-antibody titers of blood samples drawn at the time of hospitalization for 11 patients and at the time of active infection for 1 asymptomatic person ranged from 1:1,024 to 1:4,096. Five of eight patients with babesiosis also had significant immunoglobulin G or immunoglobulin M titers (1:640 to 1:5,120) to Borrelia burgdorferi. B. microti was isolated in Syrian hamsters inoculated with blood from 7 of 12 patients tested and was also isolated from mice captured in six towns. The peridomestic nature of the disease was demonstrated by isolating the parasite from white-footed mice captured in or near the yards of eight different patients. Of 59 mice tested, 27 were positive and 25 were coinfected with B. burgdorferi. The isolation of B. microti from a white-footed mouse captured in north-central Connecticut (West Hartford), away from the focus of human infections in southeastern Connecticut, suggests that this pathogen may spread into other areas where Ixodes dammini, the tick vector, becomes established.

  7. Borrelia carolinensis sp. nov., a novel species of the Borrelia burgclorferi sensu lato complex isolated from rodents and a tick from the south-eastern USA

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Grubhoffer, Libor; Oliver, J. H., Jr.

    2011-01-01

    Roč. 61, č. 2 (2011), 381-383 ISSN 1466-5026 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GA206/09/1782 Institutional research plan: CEZ:AV0Z60220518 Keywords : MULTILOCUS SEQUENCE-ANALYSIS * FRAGMENT-LENGTH-POLYMORPHISM * LYME -DISEASE * RIBOSOMAL-RNA * Borrelia carolinensis sp. nov. * phylogeny Subject RIV: EE - Microbiology, Virology Impact factor: 2.268, year: 2011

  8. Detection of relapsing fever Borrelia spp., Bartonella spp. and Anaplasmataceae bacteria in argasid ticks in Algeria.

    Science.gov (United States)

    Lafri, Ismail; El Hamzaoui, Basma; Bitam, Idir; Leulmi, Hamza; Lalout, Reda; Mediannikov, Oleg; Chergui, Mohamed; Karakellah, Mohamed; Raoult, Didier; Parola, Philippe

    2017-11-01

    Argasid ticks (soft ticks) are blood-feeding arthropods that can parasitize rodents, birds, humans, livestock and companion animals. Ticks of the Ornithodoros genus are known to be vectors of relapsing fever borreliosis in humans. In Algeria, little is known about relapsing fever borreliosis and other bacterial pathogens transmitted by argasid ticks. Between May 2013 and October 2015, we investigated the presence of soft ticks in 20 rodent burrows, 10 yellow-legged gull (Larus michahellis) nests and animal shelters in six locations in two different bioclimatic zones in Algeria. Six species of argasid ticks were identified morphologically and through 16S rRNA gene sequencing. The presence and prevalence of Borrelia spp., Bartonella spp., Rickettsia spp. and Anaplasmataceae was assessed by qPCR template assays in each specimen. All qPCR-positive samples were confirmed by standard PCR, followed by sequencing the amplified fragments. Two Borrelia species were identified: Borrelia hispanica in Ornithodoros occidentalis in Mostaganem, and Borrelia cf. turicatae in Carios capensis in Algiers. One new Bartonella genotype and one new Anaplasmataceae genotype were also identified in Argas persicus. The present study highlights the presence of relapsing fever borreliosis agents, although this disease is rarely diagnosed in Algeria. Other bacteria of unknown pathogenicity detected in argasid ticks which may bite humans deserve further investigation.

  9. Differential expression of Ixodes ricinus tick genes induced by blood feeding or Borrelia burgdorferi infection

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Edwards, M. J.; Grubhoffer, Libor

    2005-01-01

    Roč. 42, č. 1 (2005), s. 36-41 ISSN 0022-2585 R&D Projects: GA AV ČR IAA6022306 Institutional research plan: CEZ:AV0Z60220518 Keywords : Ixodes ricinus * Borrelia burgdorferi * subtractive hybridization Subject RIV: EE - Microbiology, Virology Impact factor: 1.489, year: 2005

  10. Lectin-binding characteristics of a Lyme borreliosis spirochete Borrelia burgdorferi sensu stricto

    Czech Academy of Sciences Publication Activity Database

    Vancová, M.; Nebesářová, J.; Grubhoffer, Libor

    2005-01-01

    Roč. 50, č. 3 (2005), s. 229-238 ISSN 0015-5632 R&D Projects: GA ČR GA206/03/1323; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia burgdorferi * electron microscopy * lectin binding Subject RIV: EE - Microbiology, Virology Impact factor: 0.918, year: 2005

  11. Prevalence of borreliae in ixodid ticks from a floodplain forest ecosystem

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Stünzner, D.; Halouzka, Jiří; Sixl, W.; Wendelin, I.; Juřicová, Zina; Sanogo, Yibayiri Osée

    2003-01-01

    Roč. 115, 3-4 (2003), s. 121-124 ISSN 0043-5325 R&D Projects: GA MŠk ME 229; GA ČR GA206/00/1204 Institutional research plan: CEZ:AV0Z6093917 Keywords : Lyme disease * Borrelia burgdorferi * floodplain forest Subject RIV: EE - Microbiology, Virology Impact factor: 0.774, year: 2003

  12. Molecular typing of Borrelia burgdorferi sensu lato by randomly amplified polymorphic DNA fingerprinting analysis

    NARCIS (Netherlands)

    Wang, G.; van Dam, A. P.; Spanjaard, L.; Dankert, J.

    1998-01-01

    To study whether pathogenic clusters of Borrelia burgdorferi sensu lato strains occur, we typed 136 isolates, cultured from specimens from patients (n = 49) with various clinical entities and from ticks (n = 83) or dogs (n = 4) from different geographic regions, by randomly amplified polymorphic DNA

  13. A Novel Animal Model of Borrelia recurrentis Louse-Borne Relapsing Fever Borreliosis Using Immunodeficient Mice

    NARCIS (Netherlands)

    Larsson, C.; Lundqvist, J.; Rooijen, van N.; Bergstrom, S.

    2009-01-01

    Louse-borne relapsing fever (LBRF) borreliosis is caused by Borrelia recurrentis, and it is a deadly although treatable disease that is endemic in the Horn of Africa but has epidemic potential. Research on LBRF has been severely hampered because successful infection with B. recurrentis has been

  14. A Borrelia afzelii Infection Increases Larval Tick Burden on Myodes glareolus (Rodentia

    NARCIS (Netherlands)

    Duijvendijk, van Gilian; Andel, van Wouter; Fonville, Manoj; Gort, Gerrit; Hovius, Joppe W.; Sprong, Hein; Takken, Willem

    2017-01-01

    Several microorganisms have been shown to manipulate their host or vector to enhance their own transmission. Here we examined whether an infection with Borrelia afzelii affects its transmission between its bank vole (Myodes glareolus, Schreber, 1780) host and tick vector. Captive-bred bank voles

  15. Tick salivary gland extract-activated transmission of Borrelia afzelii spirochaetes

    Czech Academy of Sciences Publication Activity Database

    Pechová, Jitka; Tresová, Gabriela; Kovář, Lubomír; Kopecký, Jan

    2002-01-01

    Roč. 49, č. 2 (2002), s. 153ů159 ISSN 0015-5683 R&D Projects: GA ČR GA524/02/0901 Institutional research plan: CEZ:AV0Z6022909 Keywords : Ixodes ricinus * salivary gland extract * Borrelia afzelii Subject RIV: EC - Immunology Impact factor: 0.515, year: 2002

  16. Phylogenetic analysis of the spirochete Borrelia microti, a potential agent of relapsing fever in Iran.

    Science.gov (United States)

    Naddaf, Saied Reza; Ghazinezhad, Behnaz; Bahramali, Golnaz; Cutler, Sally Jane

    2012-09-01

    We report a role for Borrelia microti as a cause of relapsing fever in Iran supported by robust epidemiological evidence. The molecular identity of this spirochete and its relation with other relapsing fever borreliae have, until now, been poorly delineated. We analyzed an isolate of B. microti, obtained from Ornithodoros erraticus ticks, by sequencing four loci (16S rRNA, flaB, glpQ, intragenic spacer [IGS]) and comparing these sequences with those of other relapsing fever borreliae. Phylogenetic analysis using concatenated sequences of 16S rRNA, flaB, and glpQ grouped B. microti alongside three members of the African group, B. duttonii, B. recurrentis, and B. crocidurae, which are distinct from B. persica, the most prevalent established cause of tick-borne relapsing fever in Iran. The similarity values for 10 concatenated sequences totaling 2,437 nucleotides ranged from 92.11% to 99.84%, with the highest homologies being between B. duttonii and B. microti and between B. duttonii and B. recurrentis. Furthermore, the more discriminatory IGS sequence analysis corroborated the close similarity (97.76% to 99.56%) between B. microti and B. duttonii. These findings raise the possibility that both species may indeed be the same and further dispel the one-species, one-vector theory that has been the basis for classification of relapsing fever Borrelia for the last 100 years.

  17. Effect of tick saliva on immune interactions between Borrelia afzelii and murine dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Slámová, M.; Skallová, A.; Páleníková, J.; Kopecký, Jan

    2011-01-01

    Roč. 33, č. 12 (2011), 654-660 ISSN 0141-9838 R&D Projects: GA AV ČR IAA600960811; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia * dendritic cell * immune modulation * Ixodes ricinus Subject RIV: EC - Immunology Impact factor: 2.601, year: 2011

  18. Tick sialostatins L and L2 differentially influence dendritic cell responses to Borrelia spirochetes

    Czech Academy of Sciences Publication Activity Database

    Lieskovská, Jaroslava; Páleníková, Jana; Langhansová, Helena; Chagas, A. C.; Calvo, E.; Kotsyfakis, Michalis; Kopecký, Jan

    2015-01-01

    Roč. 8, MAY 15 2015 (2015), s. 275 ISSN 1756-3305 R&D Projects: GA ČR GAP302/12/2208 Institutional support: RVO:60077344 Keywords : Dendritic cell s * Borrelia burgdorferi * Tick cystatin * Signalling Subject RIV: EC - Immunology Impact factor: 3.234, year: 2015

  19. Effect of tick saliva on mechanisms of innate immune response against Borrelia afzelii

    Czech Academy of Sciences Publication Activity Database

    Kýčková, Kateřina; Kopecký, Jan

    2006-01-01

    Roč. 43, č. 4 (2006), s. 1208-1214 ISSN 0022-2585 R&D Projects: GA ČR GA524/05/0811; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Ixodes ricinus * Borrelia afzelii * phagocytosis Subject RIV: EC - Immunology Impact factor: 1.950, year: 2006

  20. Detection of relapsing fever Borrelia spp., Bartonella spp. and Anaplasmataceae bacteria in argasid ticks in Algeria.

    Directory of Open Access Journals (Sweden)

    Ismail Lafri

    2017-11-01

    Full Text Available Argasid ticks (soft ticks are blood-feeding arthropods that can parasitize rodents, birds, humans, livestock and companion animals. Ticks of the Ornithodoros genus are known to be vectors of relapsing fever borreliosis in humans. In Algeria, little is known about relapsing fever borreliosis and other bacterial pathogens transmitted by argasid ticks.Between May 2013 and October 2015, we investigated the presence of soft ticks in 20 rodent burrows, 10 yellow-legged gull (Larus michahellis nests and animal shelters in six locations in two different bioclimatic zones in Algeria. Six species of argasid ticks were identified morphologically and through 16S rRNA gene sequencing. The presence and prevalence of Borrelia spp., Bartonella spp., Rickettsia spp. and Anaplasmataceae was assessed by qPCR template assays in each specimen. All qPCR-positive samples were confirmed by standard PCR, followed by sequencing the amplified fragments. Two Borrelia species were identified: Borrelia hispanica in Ornithodoros occidentalis in Mostaganem, and Borrelia cf. turicatae in Carios capensis in Algiers. One new Bartonella genotype and one new Anaplasmataceae genotype were also identified in Argas persicus.The present study highlights the presence of relapsing fever borreliosis agents, although this disease is rarely diagnosed in Algeria. Other bacteria of unknown pathogenicity detected in argasid ticks which may bite humans deserve further investigation.

  1. Detection and identification of Anaplasma phagocytophilum, Borrelia burgdorferi, and Rickettsia helvetica in Danish Ixodes ricinus ticks

    DEFF Research Database (Denmark)

    Skarphédinsson, Sigurdur; Lyholm, Birgitte Fjendbo; Ljungberg, Marianne

    2007-01-01

    % of adult ticks. The difference in prevalence between Anaplasma and Borrelia in adult ticks supports the idea that their maintenance cycles in nature may be different. Ticks were also infected with Rickettsia helvetica. Our study indicates that A. phagocytophilum prevalence in ticks in Denmark is as high...

  2. Granuloma Annulare and Morphea: Correlation with Borrelia burgdorferi Infections and Chlamydia-related Bacteria

    Directory of Open Access Journals (Sweden)

    Lauri Tolkki

    2017-12-01

    Full Text Available A retrospective study of 109 skin biopsies with granuloma annulare (GA or morphea histology from patients with suspected tick bite was performed. Biopsies were tested for cutaneous Borrelia burgdorferi DNA using PCR. The same biopsies were analysed for tick-borne novel agents, Chlamydia-related bacteria (members of the Chlamydiales order, using a PCR-based method. Borrelia DNA was detected in 7/73 (9.6% biopsies with GA and in 1/36 (2.8 % biopsies with morphea, while Chlamydiales DNA was found in 53/73 (72.6% biopsies with GA and 25/34 (73.4% biopsies with morphea. All Borrelia DNA-positive GA samples were also positive for Chlamydiales DNA. The Chlamydiales sequences detected in GA were heterogeneous and contained Waddliaceae and Rhabdochlamydiaceae bacteria, which are also present in Ixodes ricinus ticks, while the Chlamydiales sequences detected in morphea closely resembled those found in healthy skin. In conclusion, tick-mediated infections can trigger GA in some cases, while correlation of either Borrelia or Chlamydiales with morphea is unlikely.

  3. Evidence of Borrelia in wild and domestic mammals from the state of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Emmanuel Montandon

    Full Text Available The main of the study was to evaluate the presence of Borrelia burgdorferi infection in domestic and wild vertebrates and ectoparasites in endemic areas from the state of Minas Gerais, Brazil. A total of 445 serum samples were examined by ELISA, which used the Borrelia burgdorferi strain G39/40 U.S. source and 3,821 tick samples were tested by polymerase chain reaction (PCR. B. burgdorferi antibodies were found in 30 serum samples (6.74%; three in marsupials (7.69%, three in rodents (2.80%, nine in dogs (6.25%, and 15 in horses (9.68%. Nested-PCR performed in DNA samples obtained from collected ticks demonstrated negative results. Although attempts to amplify B. burgdorferi DNA from ticks had been not successful, the presence of seroreactive vertebrates suggests the possibility the Borrelia species circulating in these regions. Further research is required to provide information on the presence of Borrelia in Brazilian territory and its association with Baggio-Yoshinari syndrome.

  4. Human pathogenic borreliae in Ixodes ricinus ticks in natural and urban ecosystem (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Venclíková, Kristýna; Betášová, Lenka; Šikutová, Silvie; Jedličková, Petra; Hubálek, Zdeněk; Rudolf, Ivo

    2014-01-01

    Roč. 59, č. 4 (2014), s. 717-720 ISSN 1230-2821 EU Projects: European Commission(XE) 261504 - EDENEXT Institutional support: RVO:68081766 Keywords : Ixodes ricinus * Borrelia burgdorgeri s.l. * genomic species * ixodid ticks Subject RIV: EE - Microbiology, Virology Impact factor: 0.905, year: 2014

  5. Tick saliva suppresses IFN signalling in dendritic cells upon Borrelia afzelii infection

    Czech Academy of Sciences Publication Activity Database

    Lieskovská, Jaroslava; Kopecký, Jan

    2012-01-01

    Roč. 34, č. 1 (2012), s. 32-39 ISSN 0141-9838 R&D Projects: GA MŠk(CZ) LC06009 Institutional support: RVO:60077344 Keywords : Borrelia * dendritic cells * interferon signalling * tick saliva Subject RIV: EC - Immunology Impact factor: 2.208, year: 2012

  6. First detection of Borrelia miyamotoi in Ixodes ricinus ticks from northern Italy.

    NARCIS (Netherlands)

    Ravagnan, Silvia; Tomassone, Laura; Montarsi, Fabrizio; Krawczyk, Aleksandra Iwona; Mastrorilli, Eleonora; Sprong, Hein; Milani, Adelaide; Rossi, Luca; Capelli, Gioia

    2018-01-01

    Borrelia miyamotoi is a spirochete transmitted by several ixodid tick species. It causes a relapsing fever in humans and is currently considered as an emerging pathogen. In Europe, B. miyamotoi seems to occur at low prevalence in Ixodes ricinus ticks but has a wide distribution. Here we report the

  7. An Ixodes ricinus Tick Salivary Lectin Pathway Inhibitor Protects Borrelia burgdorferi sensu lato from Human Complement

    NARCIS (Netherlands)

    Wagemakers, Alex; Coumou, Jeroen; Schuijt, Tim J.; Oei, Anneke; Nijhof, Ard M.; van 't Veer, Cornelis; van der Poll, Tom; Bins, Adriaan D.; Hovius, Joppe W. R.

    2016-01-01

    We previously identified tick salivary lectin pathway inhibitor (TSLPI) in Ixodes scapularis, a vector for Borrelia burgdorferi sensu stricto (s.s.) in North America. TSLPI is a salivary protein facilitating B. burgdorferi s.s. transmission and acquisition by inhibiting the host lectin complement

  8. Large scale spatial risk and comparative prevalence of Borrelia miyamotoi and Borrelia burgdorferi sensu lato in Ixodes pacificus.

    Directory of Open Access Journals (Sweden)

    Kerry Padgett

    Full Text Available Borrelia miyamotoi is a newly described emerging pathogen transmitted to people by Ixodes species ticks and found in temperate regions of North America, Europe, and Asia. There is limited understanding of large scale entomological risk patterns of B. miyamotoi and of Borreila burgdorferi sensu stricto (ss, the agent of Lyme disease, in western North America. In this study, B. miyamotoi, a relapsing fever spirochete, was detected in adult (n=70 and nymphal (n=36 Ixodes pacificus ticks collected from 24 of 48 California counties that were surveyed over a 13 year period. Statewide prevalence of B. burgdorferi sensu lato (sl, which includes B. burgdorferi ss, and B. miyamotoi were similar in adult I. pacificus (0.6% and 0.8%, respectively. In contrast, the prevalence of B. burgdorferi sl was almost 2.5 times higher than B. miyamotoi in nymphal I. pacificus (3.2% versus 1.4%. These results suggest similar risk of exposure to B. burgdorferi sl and B. miyamotoi from adult I. pacificus tick bites in California, but a higher risk of contracting B. burgdorferi sl than B. miyamotoi from nymphal tick bites. While regional risk of exposure to these two spirochetes varies, the highest risk for both species is found in north and central coastal California and the Sierra Nevada foothill region, and the lowest risk is in southern California; nevertheless, tick-bite avoidance measures should be implemented in all regions of California. This is the first study to comprehensively evaluate entomologic risk for B. miyamotoi and B. burgdorferi for both adult and nymphal I. pacificus, an important human biting tick in western North America.

  9. Crystal Structure of Borrelia turicatae protein, BTA121, a differentially regulated  gene in the tick-mammalian transmission cycle of relapsing fever spirochetes

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Zhipu; Kelleher, Alan J.; Darwiche, Rabih; Hudspeth, Elissa M.; Shittu, Oluwatosin K.; Krishnavajhala, Aparna; Schneiter, Roger; Lopez, Job E.; Asojo, Oluwatoyin A. (Baylor); (Fribourg); (NCI)

    2017-11-10

    Tick-borne relapsing fever (RF) borreliosis is a neglected disease that is often misdiagnosed. RF species circulating in the United States include Borrelia turicatae, which is transmitted by argasid ticks. Environmental adaptation by RF Borrelia is poorly understood, however our previous studies indicated differential regulation of B. turicatae genes localized on the 150 kb linear megaplasmid during the tick-mammalian transmission cycle, including bta121. This gene is up-regulated by B. turicatae in the tick versus the mammal, and the encoded protein (BTA121) is predicted to be surface localized. The structure of BTA121 was solved by single-wavelength anomalous dispersion (SAD) using selenomethionine-derivative protein. The topology of BTA121 is unique with four helical domains organized into two helical bundles. Due to the sequence similarity of several genes on the megaplasmid, BTA121 can serve as a model for their tertiary structures. BTA121 has large interconnected tunnels and cavities that can accommodate ligands, notably long parallel helices, which have a large hydrophobic central pocket. Preliminary in-vitro studies suggest that BTA121 binds lipids, notably palmitate with a similar order of binding affinity as tablysin-15, a known palmitate-binding protein. The reported data will guide mechanistic studies to determine the role of BTA121 in the tick-mammalian transmission cycle of B. turicatae.

  10. Natural foci of Borrelia lusitaniae in a mountain region of Central Europe.

    Science.gov (United States)

    Tarageľová, Veronika Rusňáková; Mahríková, Lenka; Selyemová, Diana; Václav, Radovan; Derdáková, Markéta

    2016-03-01

    Lyme borreliosis is the most prevalent tick-borne disease in Europe. It is caused by spirochaetes of the Borrelia burgdorferi sensu lato (s.l.) complex and transmitted to humans by ticks of the genus Ixodes. Borrelia afzelii, Borrelia garinii, and Borrelia valaisiana are the most common genospecies in Central Europe. In contrast, Borrelia lusitaniae predominates in Mediterranean countries such as Portugal, Morocco, and Tunisia. In Slovakia, its prevalence is low and restricted to only a few sites. The aim of our research was to study the expansion of ticks into higher altitudes in the ecosystem of the Malá Fatra mountains (north Slovakia) and their infection with B. burgdorferi s.l. pathogens. Questing ticks were collected by flagging in seven years (2004, 2006-2011) at three different altitudes: low (630-660 m above sea level (ASL)), intermediate (720-750 m ASL), and high (1040-1070 m ASL). Tick abundance was highest at the lowest altitude and lowest at the highest altitude. The average infection prevalence of B. burgdorferi s.l. in nymphs and adults was 16.8% and 36.2%, respectively. The number of infected ticks decreased from 38.5% at the lowest altitude to 4.4% at the highest altitude. B. lusitaniae was the most frequently found genospecies (>60% of the ticks found positive for B. burgdorferi s.l.) in all sites in all the studied years with the exception of 2008 when B. afzelii predominated (62%). Our study confirms the spread of Ixodes ricinus ticks to higher altitudes in Slovakia. The discovery that our mountain study sites were a natural foci of B. lusitaniae was unexpected because this genospecies is usually associated with lizards and xerothermic habitats. Copyright © 2015 Elsevier GmbH. All rights reserved.

  11. The CMS Outer Hadron Calorimeter

    CERN Document Server

    Acharya, Bannaje Sripathi; Banerjee, Sunanda; Banerjee, Sudeshna; Bawa, Harinder Singh; Beri, Suman Bala; Bhandari, Virender; Bhatnagar, Vipin; Chendvankar, Sanjay; Deshpande, Pandurang Vishnu; Dugad, Shashikant; Ganguli, Som N; Guchait, Monoranjan; Gurtu, Atul; Kalmani, Suresh Devendrappa; Kaur, Manjit; Kohli, Jatinder Mohan; Krishnaswamy, Marthi Ramaswamy; Kumar, Arun; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mondal, Naba Kumar; Nagaraj, P; Narasimham, Vemuri Syamala; Patil, Mandakini Ravindra; Reddy, L V; Satyanarayana, B; Sharma, Seema; Singh, B; Singh, Jas Bir; Sudhakar, Katta; Tonwar, Suresh C; Verma, Piyush

    2006-01-01

    The CMS hadron calorimeter is a sampling calorimeter with brass absorber and plastic scintillator tiles with wavelength shifting fibres for carrying the light to the readout device. The barrel hadron calorimeter is complemented with a outer calorimeter to ensure high energy shower containment in CMS and thus working as a tail catcher. Fabrication, testing and calibrations of the outer hadron calorimeter are carried out keeping in mind its importance in the energy measurement of jets in view of linearity and resolution. It will provide a net improvement in missing $\\et$ measurements at LHC energies. The outer hadron calorimeter has a very good signal to background ratio even for a minimum ionising particle and can hence be used in coincidence with the Resistive Plate Chambers of the CMS detector for the muon trigger.

  12. Origin of Outer Solar System

    Science.gov (United States)

    Holman, Matthew J.; Lindstrom, David (Technical Monitor)

    2005-01-01

    Our ongoing research program combines extensive deep and wide-field observations using a variety of observational platforms with numerical studies of the dynamics of small bodies in the outer solar system in order to advance the main scientific goals of the community studying the Kuiper belt and the outer solar system. These include: (1) determining the relative populations of the known classes of KBOs as well as other possible classes; ( 2 ) determining the size distributions or luminosity function of the individual populations or the Kuiper belt as a whole; (3) determining the inclinations distributions of these populations; (4) establishing the radial extent of the Kuiper belt; ( 5 ) measuring and relating the physical properties of different types of KBOs to those of other solar system bodies; and, (6) completing our systematic inventory of the satellites of the outer planets.

  13. Nuclear fuel grid outer strap

    International Nuclear Information System (INIS)

    Duncan, R.; Craver, J.E.

    1989-01-01

    This patent describes a nuclear reactor fuel assembly grid. It comprises a first outer grip strap segment end. The first end having a first tab arranged in substantially the same plane as the plane defined by the first end; a second outer grip strap end. The second end having a second slot arranged in substantially the same plane as the plane defined by the second end, with the tab being substantially disposed in the slot, defining a socket therebetween; and a fort tine interposed substantially perpendicularly in the socket

  14. Use of nonelectrolytes reveals the channel size and oligomeric constitution of the Borrelia burgdorferi P66 porin.

    Directory of Open Access Journals (Sweden)

    Iván Bárcena-Uribarri

    Full Text Available In the Lyme disease spirochete Borrelia burgdorferi, the outer membrane protein P66 is capable of pore formation with an atypical high single-channel conductance of 11 nS in 1 M KCl, which suggested that it could have a larger diameter than 'normal' Gram-negative bacterial porins. We studied the diameter of the P66 channel by analyzing its single-channel conductance in black lipid bilayers in the presence of different nonelectrolytes with known hydrodynamic radii. We calculated the filling of the channel with these nonelectrolytes and the results suggested that nonelectrolytes (NEs with hydrodynamic radii of 0.34 nm or smaller pass through the pore, whereas neutral molecules with greater radii only partially filled the channel or were not able to enter it at all. The diameter of the entrance of the P66 channel was determined to be ≤1.9 nm and the channel has a central constriction of about 0.8 nm. The size of the channel appeared to be symmetrical as judged from one-sidedness of addition of NEs. Furthermore, the P66-induced membrane conductance could be blocked by 80-90% by the addition of the nonelectrolytes PEG 400, PEG 600 and maltohexaose to the aqueous phase in the low millimolar range. The analysis of the power density spectra of ion current through P66 after blockage with these NEs revealed no chemical reaction responsible for channel block. Interestingly, the blockage of the single-channel conductance of P66 by these NEs occurred in about eight subconductance states, indicating that the P66 channel could be an oligomer of about eight individual channels. The organization of P66 as a possible octamer was confirmed by Blue Native PAGE and immunoblot analysis, which both demonstrated that P66 forms a complex with a mass of approximately 460 kDa. Two dimension SDS PAGE revealed that P66 is the only polypeptide in the complex.

  15. The Tick Salivary Protein Salp15 Inhibits the Killing of Serum-Sensitive Borrelia burgdorferi Sensu Lato Isolates▿

    OpenAIRE

    Schuijt, Tim J.; Hovius, Joppe W. R.; van Burgel, Nathalie D.; Ramamoorthi, Nandhini; Fikrig, Erol; van Dam, Alje P.

    2008-01-01

    Borrelia burgdorferi, the agent of Lyme disease, is transmitted by ticks. During transmission from the tick to the host, spirochetes are delivered with tick saliva, which contains the salivary protein Salp15. Salp15 has been shown to protect spirochetes against B. burgdorferi-specific antibodies. We now show that Salp15 from both Ixodes ricinus and Ixodes scapularis protects serum-sensitive isolates of Borrelia burgdorferi sensu lato against complement-mediated killing. I. ricinus Salp15 show...

  16. Getting Sloshed in Outer Space

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 12. Getting Sloshed in Outer Space - Liquid Behavior in Microgravity. N Ananthkrishnan. General Article Volume 12 Issue 12 December 2007 pp 40-45. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. Outer space structure and development

    International Nuclear Information System (INIS)

    Zeldovich, J.; Novikov, I.

    1975-01-01

    A brief account is presented answering the question of what in fact the outer space we observe consists of. The principle of spatial homogeneity of the universe and the idea of non-stationary cosmology are discussed. The origin and the future development of the universe are explained using the two above mentioned and some other hypotheses. (J.K.)

  18. Outer space structure and development

    Energy Technology Data Exchange (ETDEWEB)

    Zeldovich, J; Novikov, I

    1975-10-01

    A brief account is presented answering the question of what in fact the outer space we observe consists of. The principle of spatial homogeneity of the universe and the idea of non-stationary cosmology are discussed. The origin and the future development of the universe are explained using the two above mentioned and some other hypotheses.

  19. Plasmas in the outer heliosphere

    Science.gov (United States)

    Belcher, J. W.; Richardson, J. D.; Lazarus, A. J.; Gazis, P. R.; Barnes, A.

    1995-01-01

    We review the observed properties of the solar wind in the outer heliosphere, including observations from Voyager and the Pioneers, as well as from inner heliospheric probes as appropriate. These observations are crucial to modeling of the heliosphere and its interactions with the interstellar medium, since the wind ram pressure and its temporal variations are important in understanding the distance to the termination shock and heliopause and how those boundaries might vary in time. We focus on results since Solar Wind 7. Among the issues we will discuss are: (1) the time scales for and statistical properties of variations in the ram pressure in the outer heliosphere, and how those variations might affect the morphology of the heliospheric/interstellar medium interface; (2) the question of possible solar wind slowing in the outer heliosphere due to the pick-up of interstellar ions; (3) the issue of whether there is bulk heating of the solar wind associated either with interstellar ion pick-up or with continued heating due to stream-stream interactions; (4) evidence for latitudinal variations in solar wind properties; and (5) the 1.3 year periodicities apparent in the outer heliosphere, and the close correspondence with similar variations seen with inner heliospheric probes.

  20. Outer Synchronization of Complex Networks by Impulse

    International Nuclear Information System (INIS)

    Sun Wen; Yan Zizong; Chen Shihua; Lü Jinhu

    2011-01-01

    This paper investigates outer synchronization of complex networks, especially, outer complete synchronization and outer anti-synchronization between the driving network and the response network. Employing the impulsive control method which is uncontinuous, simple, efficient, low-cost and easy to implement in practical applications, we obtain some sufficient conditions of outer complete synchronization and outer anti-synchronization between two complex networks. Numerical simulations demonstrate the effectiveness of the proposed impulsive control scheme. (general)

  1. [Using the polymerase chain reaction to Borrelia burgdorferi infection in localized scleroderma injure (morphea), in Venezuelan patients].

    Science.gov (United States)

    Espinoza-León, Fabiola; Arocha, Francisco; Hassanhi, Manzur; Arévalo, Julio

    2010-09-01

    Borrelia burgdorferi is the causative agent of Lyme Borreliosis, an infectious multisystemic disease transmitted to humans by the Ixodes ticks bite. A possible association of Borrelia burgdorferi with localized scleroderma has been postulated. However, published data do not provide unequivocal results. Previous serologic analysis of patients with localized scleroderma in South American countries (including Venezuela), have been reported as yielding some reactivity. The present study looked for evidence of Borrelia burgdorferi infection in venezuelan patients with localized scleroderma, using the polymerase chain reaction to analyze 21 skin samples of patients with this skin condition. The results were negative in all the samples studied. Our data do not support an association of Borrelia burgdorferi infection and the sclerotic lesions of localized scleroderma; but do not rule out the possibility of a relationship between localized scleroderma and an unknown geno-specie of Borrelia burgdorferi sensu lato complex, a different Borrelia specie or a different spirochetal organism, as the etiological agents of the skin lesions in this area.

  2. Inner- and outer-sphere complexation of ions at the goethite-solution interface

    NARCIS (Netherlands)

    Rahnemaie, R.; Hiemstra, T.; Riemsdijk, van W.H.

    2006-01-01

    Formation of inner- and outer-sphere complexes of environmentally important divalent ions on the goethite surface was examined by applying the charge distribution CD model for inner- and outer-sphere complexation. The model assumes spatial charge distribution between the surface (0-plane) and the

  3. [Recombinant OspC identification and antigenicity detection from Borrelia burgdorferi PD91 in China].

    Science.gov (United States)

    Chen, Jian; Wan, Kang-Lin

    2003-10-01

    To recombine OspC gene from Borrelia burgdorferi PD91 of China and expressed it in E. coli for early diagnosis of Lyme disease. The OspC gene was amplified from the genome of Borrelia burgdorferi PD91 strain by polymerase chain reaction and recombined with plasmid PET-11D. The recombinant plasmid PET-11D-OspC was identified with PCR, restriction endonuclease analysis and sequencing. The antigenicity was verified with Western Blot. OspC gene was cloned correctly into vector PET-11D. The resultant sequence was definitely different from the published sequence. The recombinant OspC seemed to have had strong antigenicity. The findings laid basis for the studies on early diagnosis of Lyme disease.

  4. Analysis of nanomechanical properties of Borrelia burgdorferi spirochetes under the influence of lytic factors in an in vitro model using atomic force microscopy

    Directory of Open Access Journals (Sweden)

    Małgorzata Tokarska-Rodak

    2015-11-01

    Full Text Available Background: Atomic force microscopy (AFM is an experimental technique which recently has been used in biology, microbiology, and medicine to investigate the topography of surfaces and in the evaluation of mechanical properties of cells. The aim of this study was to evaluate the influence of the complement system and specific anti-Borrelia antibodies in in vitro conditions on the modification of nanomechanical features of B. burgdorferi B31 cells. Material and methods: In order to assess the influence of the complement system and anti-Borrelia antibodies on B. burgdorferi s.s. B31 spirochetes, the bacteria were incubated together with plasma of identified status. The samples were applied on the surface of mica disks. Young’s modulus and adhesive forces were analyzed with a NanoScope V, MultiMode 8 AFM microscope (Bruker by the PeakForce QNM technique in air using NanoScope Analysis 1.40 software (Bruker.Results/Conclusion: The average value of flexibility of spirochetes’ surface expressed by Young’s modulus was 10185.32 MPa, whereas the adhesion force was 3.68 nN. AFM is a modern tool with a broad spectrum of observational and measurement abilities. Young’s modulus and the adhesion force can be treated as parameters in the evaluation of intensity and changes which take place in pathogenic microorganisms under the influence of various lytic factors. The visualization of the changes in association with nanomechanical features provides a realistic portrayal of the lytic abilities of the elements of the innate and adaptive human immune system.

  5. Turbine exhaust diffuser with region of reduced flow area and outer boundary gas flow

    Science.gov (United States)

    Orosa, John

    2014-03-11

    An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

  6. Reclassification of Borrelia spp. isolated in South Korea using Multilocus Sequence Typing.

    Science.gov (United States)

    Park, Kyung-Hee; Choi, Yeon-Joo; Kim, Jeoungyeon; Park, Hye-Jin; Song, Dayoung; Jang, Won-Jong

    2018-05-31

    Using Borrelia isolated from South Korea, we evaluated by MLST and three intergenic genes (16S rRNA, ospA, and 5S-23S IGS) typing to analyze the relationship between host and vector and molecular background. Using the MLST analysis, we identified B. afzelii, B. yangtzensis, B. garinii, and B. bavariensis. This study was first report of the identification of B. yangtzensis using the MLST in South Korea.

  7. Updates on Borrelia burgdorferi sensu lato complex with respect to public health

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Grubhoffer, Libor; Oliver, J. H., Jr.

    2011-01-01

    Roč. 2, č. 3 (2011), s. 123-128 ISSN 1877-959X R&D Projects: GA MŠk(CZ) LC06009; GA ČR GA206/09/1782 Institutional research plan: CEZ:AV0Z60220518 Keywords : Spirochetes * Borrelia * Genetic diversity * Lyme borreliosis * Distribution * New species Subject RIV: EE - Microbiology, Virology Impact factor: 2.370, year: 2011

  8. A Case of Canine Borreliosis in Iran Caused by Borrelia persica

    OpenAIRE

    Shirani, Darush; Rakhshanpoor, Alaleh; Cutler, Sally J.; Ghazinezhad, Behnaz; Naddaf, Saied Reza

    2016-01-01

    Tick-borne relapsing fever is an endemic disease in Iran, with most cases attributed to infection by B. persica, which is transmitted by Ornithodoros tholozani soft ticks. Here, we report spirochetemia in blood of a puppy residing in Tehran, Iran. The causative species was identified by use of highly discriminative IGS sequencing; the 489 bp IGS sequence obtained in our study showed 99% identity (100% coverage) when compared with Borrelia persica sequences derived from clinical cases or from ...

  9. In silico evaluation of PCR - primers for detection of Lyme Borrelia

    OpenAIRE

    Sultan, Nasir

    2016-01-01

    Lyme borreliosis (LB) or Lyme disease is the most prevalent vector-borne disease in US and Europe. The etiologic is some species of tick-borne spirochetes Borrelia burgdorferi sensu lato (B. burgdorferi sl) complex. The most common clinical symptoms of LB is the erythema migrans (EM). The pathogen is transmitted to humans through the tick bite of Ixodes species, and spread to cause more severe manifestations such as Acrodermatitis Chronica Atrophicans (ACA), Lyme arthritis, and neuroborrelios...

  10. Borrelia burgdorferi infection and immunity in mice deficient in the fifth component of complement.

    OpenAIRE

    Bockenstedt, L K; Barthold, S; Deponte, K; Marcantonio, N; Kantor, F S

    1993-01-01

    When immunocompetent mice are inoculated with Borrelia burgdorferi, they develop acute arthritis and carditis that undergo spontaneous regression despite the persistence of infection. Specific T- and/or B-cell immunity appears to be necessary for resolution of disease manifestations. Humoral immune responses to B. burgdorferi are also important in prevention of B. burgdorferi infection, in that passive transfer of immune sera or protective monoclonal antibodies prevents the spirochete from es...

  11. Antibody responses to Borrelia burgdorferi detected by western blot vary geographically in Canada

    OpenAIRE

    Ogden, Nicholas H.; Arsenault, Julie; Hatchette, Todd F.; Mechai, Samir; Lindsay, L. Robbin

    2017-01-01

    Lyme disease is emerging in eastern and central Canada, and most cases are diagnosed using the two-tier serological test (Enzyme Immuno Assay [EIA] followed by Western blot [WB]). Simplification of this algorithm would be advantageous unless it impacts test performance. In this study, accuracy of individual proteins of the IgG WB algorithm in predicting the overall test result in samples from Canadians was assessed. Because Borrelia burgdorferi strains vary geographically in Canada, geographi...

  12. Suppression of Long-Lived Humoral Immunity Following Borrelia burgdorferi Infection.

    Directory of Open Access Journals (Sweden)

    Rebecca A Elsner

    2015-07-01

    Full Text Available Lyme Disease caused by infection with Borrelia burgdorferi is an emerging infectious disease and already by far the most common vector-borne disease in the U.S. Similar to many other infections, infection with B. burgdorferi results in strong antibody response induction, which can be used clinically as a diagnostic measure of prior exposure. However, clinical studies have shown a sometimes-precipitous decline of such antibodies shortly following antibiotic treatment, revealing a potential deficit in the host's ability to induce and/or maintain long-term protective antibodies. This is further supported by reports of frequent repeat infections with B. burgdorferi in endemic areas. The mechanisms underlying such a lack of long-term humoral immunity, however, remain unknown. We show here that B. burgdorferi infected mice show a similar rapid disappearance of Borrelia-specific antibodies after infection and subsequent antibiotic treatment. This failure was associated with development of only short-lived germinal centers, micro-anatomical locations from which long-lived immunity originates. These showed structural abnormalities and failed to induce memory B cells and long-lived plasma cells for months after the infection, rendering the mice susceptible to reinfection with the same strain of B. burgdorferi. The inability to induce long-lived immune responses was not due to the particular nature of the immunogenic antigens of B. burgdorferi, as antibodies to both T-dependent and T-independent Borrelia antigens lacked longevity and B cell memory induction. Furthermore, influenza immunization administered at the time of Borrelia infection also failed to induce robust antibody responses, dramatically reducing the protective antiviral capacity of the humoral response. Collectively, these studies show that B. burgdorferi-infection results in targeted and temporary immunosuppression of the host and bring new insight into the mechanisms underlying the failure

  13. Reptile-associated Borrelia species in the goanna tick (Bothriocroton undatum) from Sydney, Australia

    Czech Academy of Sciences Publication Activity Database

    Panetta, J. L.; Šíma, Radek; Calvani, N.E.D.; Hajdušek, Ondřej; Chandra, S.; Panuccio, J.; Šlapeta, J.

    2017-01-01

    Roč. 10, 20 December (2017), č. článku 616. ISSN 1756-3305 R&D Projects: GA ČR GA17-27393S; GA ČR GA17-27386S Institutional support: RVO:60077344 Keywords : Borrelia * Bothriocroton undatum * Coxiella burnetii * DNA extraction * Goanna tick * Illumina * Ixodidae * MiSeq Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 3.080, year: 2016

  14. Antibodies to Rickettsia spp. and Borrelia burgdorferi in Spanish Wild Red Foxes (Vulpes vulpes).

    Science.gov (United States)

    Lledó, Lourdes; Serrano, José Luis; Isabel Gegúndez, María; Giménez-Pardo, Consuelo; Saz, José Vicente

    2016-01-01

    We examined 314 red foxes (Vulpes vulpes) from the province of Soria, Spain, for Rickettsia typhi, Rickettsia slovaca, and Borrelia burgdorferi infection. Immunofluorescence assays showed 1.9% had antibodies to R. typhi, 6.7% had antibodies to R. slovaca, and 8.3% had antibodies to B. burgdorferi. Serostatus was not correlated with sex or age. Because red foxes can be infected by Rickettsiae and B. burgdorferi, presence of red foxes may be and indicator for the presence of these pathogens.

  15. Risk of occupational infections caused by Borrelia burgdorferi among forestry workers and farmers

    Directory of Open Access Journals (Sweden)

    Małgorzata Tokarska-Rodak

    2014-02-01

    Full Text Available Background: The aim of the work was to analyze the incidence of infection with Borrelia burgdorferi in forestry workers and farmers, major groups occupationally exposed to tick bites. Material and Methods: The study group included 275 workers (171 foresters and 104 farmers. The control group consisted of 45 people, who have not been occupationally exposed to tick bites. The screening Elisa and Wb tests for the presence of anti-Borrelia IgM/IgG antibodies were performed in all subjects of the study and control groups. Statistical analysis was performed using the Chi2 test. Results: The positive results denoting the presence of anti-Borrelia IgM/IgG antibodies were found in 55% of farmers and 28% of foresters occupationally exposed to Lyme borreliosis and coming from the area of South Podlasie Lowland and Lublin Polesie. The differences between the forestry workers and the control group (p ≤ 0.00001 and between farmers and the control group (p ≤ 0.001 were statistically significant. The species, such as B. spielmanii and B. bavariensis, which have not yet been reported in Poland, are significant etiologic agents of Lyme disease. Conclusion: The risk of occupational exposure to the B. burgdorferi infection is high for foresters and farmers, and the infection with spirochetes is frequently confirmed on the basis of positive results of the Wb test. The presence of specific antibodies against protein antigens of B. spielmanii and B. bavariensis suggest that these bacteria can cause Lyme disease both independently and in participation with other Borrelia species, which influences the development of the clinical manifestations of infection. Med Pr 2014;65(1:109–117

  16. Few vertebrate species dominate the Borrelia burgdorferi s.l. life cycle

    Science.gov (United States)

    Hofmeester, T. R.; Coipan, E. C.; van Wieren, S. E.; Prins, H. H. T.; Takken, W.; Sprong, H.

    2016-04-01

    Background. In the northern hemisphere, ticks of the Ixodidae family are vectors of diseases such as Lyme borreliosis, Rocky Mountain spotted fever and tick-borne encephalitis. Most of these ticks are generalists and have a three-host life cycle for which they are dependent on three different hosts for their blood meal. Finding out which host species contribute most in maintaining ticks and the pathogens they transmit, is imperative in understanding the drivers behind the dynamics of a disease. Methods. We performed a systematic review to identify the most important vertebrate host species for Ixodes ricinus and Borrelia burgdorferi s.l. as a well-studied model system for tick-borne diseases. We analyzed data from 66 publications and quantified the relative contribution for 15 host species. Review results. We found a positive correlation between host body mass and tick burdens for the different stages of I. ricinus. We show that nymphal burdens of host species are positively correlated with infection prevalence with B. burgdorferi s.l., which is again positively correlated with the realized reservoir competence of a host species for B. burgdorferi s.l. Our quantification method suggests that only a few host species, which are amongst the most widespread species in the environment (rodents, thrushes and deer), feed the majority of I. ricinus individuals and that rodents infect the majority of I. ricinus larvae with B. burgdorferi s.l. Discussion. We argue that small mammal-transmitted Borrelia spp. are maintained due to the high density of their reservoir hosts, while bird-transmitted Borrelia spp. are maintained due to the high infection prevalence of their reservoir hosts. Our findings suggest that Ixodes ricinus and Borrelia burgdorferi s.l. populations are maintained by a few widespread host species. The increase in distribution and abundance of these species, could be the cause for the increase in Lyme borreliosis incidence in Europe in recent decades.

  17. Heating of the outer solar atmosphere

    International Nuclear Information System (INIS)

    Parker, E.N.

    1983-01-01

    The author discusses the idea that there must be a source of magnetic fields somewhere below the solar surface. He starts by considering present day ideas about the sun's internal structure. The sun has a radius of approximately 700,000 km, of which the outer 100,000 km or so is the convective zone, according to mixing-length models. The dynamo is believed to operate in the convective zone, across which there may be a 5-10% variation in the angular velocity. There are the stretched east-west fields similar to the ones in the earth's core. Associated with these are poloidal fields which contribute to a net dipole moment of the sun and are generated by a dynamo. The author shows that essentially no magnetic field configuration has an equilibrium; they dissipate quickly in spite of the high conductivity in fluid motions and heating. This is probably the major part of the heating of the sun's outer atmosphere. (Auth.)

  18. Mitochondrial dysfunction underlying outer retinal diseases

    DEFF Research Database (Denmark)

    Lefevere, Evy; Toft-Kehler, Anne Katrine; Vohra, Rupali

    2017-01-01

    Dysfunction of photoreceptors, retinal pigment epithelium (RPE) or both contribute to the initiation and progression of several outer retinal disorders. Disrupted Müller glia function might additionally subsidize to these diseases. Mitochondrial malfunctioning is importantly associated with outer...

  19. Identification of outer membrane proteins of Yersinia pestis through biotinylation

    NARCIS (Netherlands)

    Smither, S.J.; Hill, J.; Baar, B.L.M. van; Hulst, A.G.; Jong, A.L. de; Titball, R.W.

    2007-01-01

    The outer membrane of Gram-negative bacteria contains proteins that might be good targets for vaccines, antimicrobials or detection systems. The identification of surface located proteins using traditional methods is often difficult. Yersinia pestis, the causative agent of plague, was labelled with

  20. Borrelia persica infection in dogs and cats: clinical manifestations, clinicopathological findings and genetic characterization.

    Science.gov (United States)

    Baneth, Gad; Nachum-Biala, Yaarit; Halperin, Tamar; Hershko, Yizhak; Kleinerman, Gabriela; Anug, Yigal; Abdeen, Ziad; Lavy, Eran; Aroch, Itamar; Straubinger, Reinhard K

    2016-05-10

    Relapsing fever (RF) is an acute infectious disease caused by arthropod-borne spirochetes of the genus Borrelia. The disease is characterized by recurrent episodes of fever that concur with spirochetemia. The RF borrelioses include louse-borne RF caused by Borrelia recurrentis and tick-borne endemic RF transmitted by argasid soft ticks and caused by several Borrelia spp. such as B. crocidurae, B. coriaceae, B. duttoni, B. hermsii, B. hispanica and B. persica. Human infection with B. persica is transmitted by the soft tick Ornithodoros tholozani and has been reported from Iran, Israel, Egypt, India, and Central Asia. During 2003-2015, five cats and five dogs from northern, central and southern Israel were presented for veterinary care and detected with borrelia spirochetemia by blood smear microscopy. The causative infective agent in these animals was identified and characterized by PCR from blood and sequencing of parts of the flagellin (flab), 16S rRNA and glycerophosphodiester phosphodiestrase (GlpQ) genes. All animals were infected with B. persica genetically identical to the causative agent of human RF. Phylogenetic analysis indicated that DNA sequences from these pet carnivores clustered together with B. persica genotypes I and II from humans and O. tholozani ticks and distinctly from other RF Borrelia spp. The main clinical findings in cats included lethargy, anorexia, anemia in 5/5 cats and thrombocytopenia in 4/5. All dogs were lethargic and anorectic, 4/5 were febrile and anemic and 3/5 were thrombocytopenic. Three dogs were co-infected with Babesia spp. The animals were all treated with antibiotics and the survival rate of both dogs and cats was 80 %. The cat and dog that succumbed to disease died one day after the initiation of antibiotic treatment, while survival in the others was followed by the rapid disappearance of spirochetemia. This is the first report of disease due to B. persica infection in cats and the first case series in dogs. Infection was

  1. WORKSHOP: Inner space - outer space

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    During the first week of May, the Fermilab theoretical astrophysics group hosted an international conference on science at the interface of particle physics and cosmology/astrophysics. The conference (Inner Space-Outer Space) was attended by a very diverse group of more than 200 physical scientists, including astronomers, astrophysicists, cosmologists, low-temperature physicists, and elementary particle theorists and experimentalists. The common interest which brought this diverse group to gether is the connection between physics on the smallest scale probed by man - the realm of elementary particle physics - and physics on the largest scale imaginable (the entire Universe) - the realm of cosmology

  2. WORKSHOP: Inner space - outer space

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1984-09-15

    During the first week of May, the Fermilab theoretical astrophysics group hosted an international conference on science at the interface of particle physics and cosmology/astrophysics. The conference (Inner Space-Outer Space) was attended by a very diverse group of more than 200 physical scientists, including astronomers, astrophysicists, cosmologists, low-temperature physicists, and elementary particle theorists and experimentalists. The common interest which brought this diverse group to gether is the connection between physics on the smallest scale probed by man - the realm of elementary particle physics - and physics on the largest scale imaginable (the entire Universe) - the realm of cosmology.

  3. Outer scale of atmospheric turbulence

    Science.gov (United States)

    Lukin, Vladimir P.

    2005-10-01

    In the early 70's, the scientists in Italy (A.Consortini, M.Bertolotti, L.Ronchi), USA (R.Buser, Ochs, S.Clifford) and USSR (V.Pokasov, V.Lukin) almost simultaneously discovered the phenomenon of deviation from the power law and the effect of saturation for the structure phase function. During a period of 35 years we have performed successively the investigations of the effect of low-frequency spectral range of atmospheric turbulence on the optical characteristics. The influence of the turbulence models as well as a outer scale of turbulence on the characteristics of telescopes and systems of laser beam formations has been determined too.

  4. Development and optimization of an in vitro cultivation protocol allows for isolation of Borrelia miyamotoi from patients with hard tick-borne relapsing fever

    NARCIS (Netherlands)

    Koetsveld, Joris; Kolyasnikova, Nadezhda M.; Wagemakers, Alex; Toporkova, Marina G.; Sarksyan, Denis S.; Oei, Anneke; Platonov, Alexander E.; Hovius, Joppe W.

    2017-01-01

    Objectives: Borrelia miyamotoi has been shown to infect humans in Eurasia and North America causing hard tick-borne relapsing fever (HTBRF). In vitro cultivation of B. miyamotoi was described recently; but clinical isolation of relapsing fever Borrelia is cumbersome. Our aim was to develop a

  5. A divergent spirochete strain isolated from a resident of the southeastern United States was identified by multilocus sequence typing as Borrelia bissettii

    Czech Academy of Sciences Publication Activity Database

    Golovchenko, Maryna; Vancová, Marie; Clark, K.; Oliver, J. H., Jr.; Grubhoffer, Libor; Rudenko, Natalia

    2016-01-01

    Roč. 9, FEB 4 (2016), č. článku 68. ISSN 1756-3305 EU Projects: European Commission(XE) 278976 - ANTIGONE Institutional support: RVO:60077344 Keywords : Borrelia * Borrelia bissettii * MLST analysis * live spirochete * divergent strain Subject RIV: EG - Zoology Impact factor: 3.080, year: 2016

  6. Immunity against Ixodes scapularis salivary proteins expressed within 24 hours of attachment thwarts tick feeding and impairs Borrelia transmission.

    Directory of Open Access Journals (Sweden)

    Sukanya Narasimhan

    2007-05-01

    Full Text Available In North America, the black-legged tick, Ixodes scapularis, an obligate haematophagus arthropod, is a vector of several human pathogens including Borrelia burgdorferi, the Lyme disease agent. In this report, we show that the tick salivary gland transcriptome and proteome is dynamic and changes during the process of engorgement. We demonstrate, using a guinea pig model of I. scapularis feeding and B. burgdorferi transmission, that immunity directed against salivary proteins expressed in the first 24 h of tick attachment - and not later - is sufficient to evoke all the hallmarks of acquired tick-immunity, to thwart tick feeding and also to impair Borrelia transmission. Defining this subset of proteins will promote a mechanistic understanding of novel I. scapularis proteins critical for the initiation of tick feeding and for Borrelia transmission.

  7. Topological analysis of Chlamydia trachomatis L2 outer membrane protein 2

    DEFF Research Database (Denmark)

    Mygind, P; Christiansen, Gunna; Birkelund, Svend

    1998-01-01

    Using monospecific polyclonal antisera to different parts of Chlamydia trachomatis L2 outer membrane protein 2 (Omp2), we show that the protein is localized at the inner surface of the outer membrane. Omp2 becomes immunoaccessible when Chlamydia elementary bodies are treated with dithiothreitol...

  8. Ohmic losses in coaxial resonators with longitudinal inner-outer corrugation

    Energy Technology Data Exchange (ETDEWEB)

    Shenyong Hou, A. [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); Yangtze Normal University, Chongqing 408001 (China); Sheng Yu, B.; Hongfu Li, C.; Qixiang Zhao, D. [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); Xiang Li, E. [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); Queen Mary University of London, London E1 4NS (United Kingdom)

    2013-05-15

    In this paper, a coaxial resonator with longitudinal inner-outer corrugation is introduced. Its eigen-equation and expression of ohmic losses are derived. Ohmic losses in the cavity are investigated. Results show that ohmic losses in the outer and inner conductors share a similar variation trend, while the former is larger than the later. What's more, changes of the inner and outer slot depth and width induce different variations of ohmic losses on the surface of the inner and outer conductors.

  9. Borrelia burgdorferi genospecies detection by RLB hybridization in Ixodes ricinus ticks from different sites of North-Eastern Poland.

    Science.gov (United States)

    Dunaj, Justyna; Zajkowska, Joanna Maria; Kondrusik, Maciej; Gern, Lise; Rais, Oliver; Moniuszko, Anna; Pancewicz, Sławomir; Świerzbińska, Renata

    2014-01-01

    RLB (Reverse Line Blot Hybridization) is a molecular biology technique that might be used for Borrelia burgdorferi sensu lato (sl) DNA detection with genospecies specification. Among B. burgdorferi sl genospecies at least 7 are regarded as pathogenic in Europe. The aim of the study was to evaluate the frequency of different Borrelia genospecies DNA detection in Ixodes ricinus ticks in the endemic area of North-Eastern Poland by using RLB. Ixodes ricinus ticks were collected in May - June, from 6 different sites in North-Eastern Poland (Jakubin, Kolno, Grajewo, Suwałki, Siemiatycze, Białowieża) by flagging. Extracted DNA was amplified by polymerase chain reaction (PCR) targeting the intergenic spacer 5S 23S of B. burgdorferi sl. PCR products were hybridised to 15 different oligonucleotide probes for 9 different Borrelia genospecies (B. burgdorferi sl, B. burgdorferi ss, B. garinii, B. afzelii, B. valaisiana, B. lusitaniae, B. spielmanii, B. bissettii and B. relapsing fever-like spirochetes (B. myamotoi)) by RLB. Borrelia genospecies DNA was detected in 205 Ixodes ricinus ticks. Among 14 infected with Borrelia ticks, 4 were identified as B. garinii and 10 as B. afzelii. Higher numbers of infected ticks were noticed in the eastern part of the research area, where large forest complexes dominate. Nymphs appeared to be the most frequently infected tick stage, which has an epidemiological meaning in the incidence of Lyme borreliosis. The study demonstrated that RLB might be easily used in Borrelia DNA detection with genospecies-identification, and indicated the domination of B. afzelii and B. garinii in ticks from North-Eastern Poland.

  10. Borreliacidal activity of Borrelia metal transporter A (BmtA binding small molecules by manganese transport inhibition

    Directory of Open Access Journals (Sweden)

    Wagh D

    2015-02-01

    Full Text Available Dhananjay Wagh,* Venkata Raveendra Pothineni,* Mohammed Inayathullah, Song Liu, Kwang-Min Kim, Jayakumar Rajadas Biomaterials and Advanced Drug Delivery Laboratory, Stanford Cardiovascular Pharmacology Division, Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA *These authors contributed equally to this work  Abstract: Borrelia burgdorferi, the causative agent of Lyme disease, utilizes manganese (Mn for its various metabolic needs. We hypothesized that blocking Mn transporter could be a possible approach to inhibit metabolic activity of this pathogen and eliminate the infection. We used a combination of in silico protein structure prediction together with molecular docking to target the Borrelia metal transporter A (BmtA, a single known Mn transporter in Borrelia and screened libraries of FDA approved compounds that could potentially bind to the predicted BmtA structure with high affinity. Tricyclic antihistamines such as loratadine, desloratadine, and 3-hydroxydesloratadine as well as yohimbine and tadalafil demonstrated a tight binding to the in silico folded BmtA transporter. We, then, tested borreliacidal activity and dose response of the shortlisted compounds from this screen using a series of in vitro assays. Amongst the probed compounds, desloratadine exhibited potent borreliacidal activity in vitro at and above 78 µg/mL (250 µM. Borrelia treated with lethal doses of desloratadine exhibited a significant loss of intracellular Mn specifically and a severe structural damage to the bacterial cell wall. Our results support the possibility of developing a novel, targeted therapy to treat Lyme disease by targeting specific metabolic needs of Borrelia.  Keywords: Lyme disease, BmtA, Borrelia burgdorferi, desloratadine, Bac Titer-Glo assay

  11. Rotational instability in the outer region of protoplanetary disks

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Tomohiro [Department of Astronomy, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Nomura, Hideko; Takeuchi, Taku, E-mail: ono.t@kusastro.kyoto-u.ac.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8551 (Japan)

    2014-05-20

    We analytically calculate the marginally stable surface density profile for the rotational instability of protoplanetary disks. The derived profile can be utilized for considering the region in a rotating disk where radial pressure gradient force is comparable to the gravitational force, such as an inner edge, steep gaps or bumps, and an outer region of the disk. In this paper, we particularly focus on the rotational instability in the outer region of disks. We find that a protoplanetary disk with a surface density profile of similarity solution becomes rotationally unstable at a certain radius, depending on its temperature profile and a mass of the central star. If the temperature is relatively low and the mass of the central star is high, disks have rotationally stable similarity profiles. Otherwise, deviation from the similarity profiles of surface density could be observable, using facilities with high sensitivity, such as ALMA.

  12. Rotational instability in the outer region of protoplanetary disks

    International Nuclear Information System (INIS)

    Ono, Tomohiro; Nomura, Hideko; Takeuchi, Taku

    2014-01-01

    We analytically calculate the marginally stable surface density profile for the rotational instability of protoplanetary disks. The derived profile can be utilized for considering the region in a rotating disk where radial pressure gradient force is comparable to the gravitational force, such as an inner edge, steep gaps or bumps, and an outer region of the disk. In this paper, we particularly focus on the rotational instability in the outer region of disks. We find that a protoplanetary disk with a surface density profile of similarity solution becomes rotationally unstable at a certain radius, depending on its temperature profile and a mass of the central star. If the temperature is relatively low and the mass of the central star is high, disks have rotationally stable similarity profiles. Otherwise, deviation from the similarity profiles of surface density could be observable, using facilities with high sensitivity, such as ALMA.

  13. Clinical characteristics associated with Borrelia burgdorferi sensu lato skin culture results in patients with erythema migrans.

    Directory of Open Access Journals (Sweden)

    Franc Strle

    Full Text Available Clinical characteristics associated with isolation of Borrelia burgdorferi sensu lato from skin have not been fully evaluated. To gain insight into predictors for a positive EM skin culture, we compared basic demographic, epidemiologic, and clinical data in 608 culture-proven and 501 culture-negative adult patients with solitary EM. A positive Borrelia spp. skin culture was associated with older age, a time interval of >2 days between tick bite and onset of the skin lesion, EM ≥ 5 cm in diameter, and location of the lesion on the extremities, whereas several other characteristics used as clinical case definition criteria for the diagnosis of EM (such as tick bite at the site of later EM, information on expansion of the skin lesion, central clearing were not. A patient with a 15-cm EM lesion had almost 3-fold greater odds for a positive skin culture than patients with a 5-cm lesion. Patients with a free time interval between the tick bite and onset of EM had the same probability of a positive skin culture as those who did not recall a tick bite (OR=1.02; however, the two groups had >3-fold greater odds for EM positivity than patients who reported a tick bite with no interval between the bite and onset of the lesion. In conclusion, several yet not all clinical characteristics used in EM case definitions were associated with positive Borrelia spp. skin culture. The findings are limited to European patients with solitary EM caused predominantly by B. afzelii but may not be valid for other situations.

  14. Evidence that two ATP-dependent (Lon proteases in Borrelia burgdorferi serve different functions.

    Directory of Open Access Journals (Sweden)

    James L Coleman

    2009-11-01

    Full Text Available The canonical ATP-dependent protease Lon participates in an assortment of biological processes in bacteria, including the catalysis of damaged or senescent proteins and short-lived regulatory proteins. Borrelia spirochetes are unusual in that they code for two putative ATP-dependent Lon homologs, Lon-1 and Lon-2. Borrelia burgdorferi, the etiologic agent of Lyme disease, is transmitted through the blood feeding of Ixodes ticks. Previous work in our laboratory reported that B. burgdorferi lon-1 is upregulated transcriptionally by exposure to blood in vitro, while lon-2 is not. Because blood induction of Lon-1 may be of importance in the regulation of virulence factors critical for spirochete transmission, the clarification of functional roles for these two proteases in B. burgdorferi was the object of this study. On the chromosome, lon-2 is immediately downstream of ATP-dependent proteases clpP and clpX, an arrangement identical to that of lon of Escherichia coli. Phylogenetic analysis revealed that Lon-1 and Lon-2 cluster separately due to differences in the NH(2-terminal substrate binding domains that may reflect differences in substrate specificity. Recombinant Lon-1 manifested properties of an ATP-dependent chaperone-protease in vitro but did not complement an E. coli Lon mutant, while Lon-2 corrected two characteristic Lon-mutant phenotypes. We conclude that B. burgdorferi Lons -1 and -2 have distinct functional roles. Lon-2 functions in a manner consistent with canonical Lon, engaged in cellular homeostasis. Lon-1, by virtue of its blood induction, and as a unique feature of the Borreliae, may be important in host adaptation from the arthropod to a warm-blooded host.

  15. Expression of spoT in Borrelia burgdorferi during Serum Starvation

    OpenAIRE

    Concepcion, Marc B.; Nelson, David R.

    2003-01-01

    Borrelia burgdorferi, the causative agent of Lyme disease, is transmitted by the tick Ixodes scapularis. A 2.9-kb fragment containing a putative spoT gene was isolated from B. burgdorferi genomic DNA by PCR amplification and cloned into a pBAD24 vector. The cloned gene complemented Escherichia coli mutant strain CF1693, which contains deletions of both the relA and spoT genes. The spoT gene in E. coli encodes a bifunctional enzyme capable of synthesizing and degrading (p)ppGpp, which mediates...

  16. A new (14th) member of Borrelia burgdorferi sensu lato complex

    Czech Academy of Sciences Publication Activity Database

    Oliver, J.; Rudenko, Natalia; Golovchenko, Maryna; Grubhoffer, Libor

    2008-01-01

    Roč. 14, S7 (2008), S110-S110 ISSN 1198-743X. [ECCMID /18./. 19.04.2008-22.04.2008, Barcelona] R&D Projects: GA ČR(CZ) GA524/06/1479; GA MŠk(CZ) LC06009 Grant - others:National Institutes of Health (NIH)(US) R37AI-24899; Centers for Disease Control and Prevention (CDC)(US) U50/CCU410282 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia burgdorferi s.l. complex * new member * multilocus sequence analysis Subject RIV: EC - Immunology

  17. Host association of Borrelia burgdorferi sensu lato--the key role of host complement.

    Science.gov (United States)

    Kurtenbach, Klaus; De Michelis, Simona; Etti, Susanne; Schäfer, Stefanie M; Sewell, Henna-Sisko; Brade, Volker; Kraiczy, Peter

    2002-02-01

    Borrelia burgdorferi sensu lato (s.l.), the tick-borne agent of Lyme borreliosis, is a bacterial species complex comprising 11 genospecies. Here, we discuss whether the delineation of genospecies is ecologically relevant. We provide evidence that B. burgdorferi s.l. is structured ecologically into distinct clusters that are host specific. An immunological model for niche adaptation is proposed that suggests the operation of complement-mediated selection in the midgut of the feeding tick. We conclude that vertebrate hosts rather than tick species are the key to Lyme borreliosis spirochaete diversity.

  18. Erythema migrans and serodiagnosis by enzyme immunoassay and immunoblot with three borrelia species.

    Science.gov (United States)

    Stanek, G; Breier, F; Menzinger, G; Schaar, B; Hafner, M; Partsch, H

    1999-12-10

    There is wide divergence of opinion between physicians regarding the use of serological measures for the diagnosis and treatment of erythema migrans, the hallmark of Lyme borreliosis. We studied the outcome of an enzyme immunoassay and immunoblot (Western blot) used on the sera of patients who had suffered tick bite and erythema migrans, and had been subsequently treated with various antibiotics. Ninety-nine consecutive patients presenting with erythema migrans after tick bite were prospectively recruited at the outpatient department of two Vienna City hospitals and at the consultation office for Lyme borreliosis of the Institute of Hygiene. University Vienna. Blood samples were taken before antibiotic treatment and 3 and 6 months thereafter. Blood samples from 100 blood donors served as controls. Antibodies against Borrelia burgdorferi sensu lato were determined by enzyme immunoassay (IgG and IgM EIA) and by IgG immunoblot. The latter was performed with isolates of B. alzelii (H2) B. burgdorferi sensu stricto (Le) and B. garinii (W) from Austrian patients. The 4 interpretation criteria for immunoblot results were: A (3 bands out of 8), B (2 bands out of 9), C and D (1 band out of 6). In all patients, the erythema resolved within the treatment period. No complications secondary to the borrelia infection were registered. After treatment there was no significant change in titre, nor was there a difference in the immunoblot pattern between the first, second and third serum samples. Serum antibodies to B. burgdorferi were positive by EIA in 22.9% (IgG) and 2.5% (IgM). Immunoblot results offered by borrelia species and by the interpretation criteria, ranging between 8.3% (criterion A, strain Le) and 44.2% (criterion D, strain H2). By EIA, control samples were IgG and IgM positive in 5% and 1%, respectively. Positive immunoblot results with strain H2 were found in 9%, 13%, 18%, and 20% by the criteria A through D respectively. After antibiotic treatment of erythema

  19. Outer grid strap protruding spring repair apparatus

    International Nuclear Information System (INIS)

    Widener, W.H.

    1987-01-01

    This patent describes a nuclear fuel assembly grid spring repair apparatus for repairing a spring formed on an outer strap of a fuel assembly grid and having a portion protruding outwardly beyond the strap, the apparatus comprising: (a) a support frame defining an opening and having means defining a guide channel extending along the opening in a first direction; (b) means mounted on the frame and being adjustable for attaching the frame to the outer strap of the support grid so that the frame opening is aligned with the outwardly protruding spring on the outer strap; (c) an outer slide having a passageway defined therethrough and being mounted in the guide channel for reciprocable movement along the frame opening in the first direction for aligning the passageway with the outwardly protruding portion of the spring on the outer strap. The outer slide also has means defining a guide way extending along the passageway in a second direction generally orthogonal to the first direction; (d) a spring reset mechanism being operable for resetting the protruding spring to a nonprotruding position relative to the outer strap when the mechanism is aligned with the protruding portion of the spring; and (e) an inner slide supporting the spring reset mechanism and being mounted to the guide way for reciprocable movement along the passageway of the outer slide in the second direction for aligning the spring reset mechanism with the protruding portion of the spring on the outer strap

  20. Seroprevalence of anti-Toxoplasma gondii and anti-Borrelia species antibodies in patients with schizophrenia: a case-control study from western Turkey.

    Science.gov (United States)

    Cevizci, Sibel; Celik, Merve; Akcali, Alper; Oyekcin, Demet Gulec; Sahin, Ozlem Oztürk; Bakar, Coskun

    2015-06-01

    We examined IgG antibody seroprevalence and risk factors for anti-Toxoplasma gondii and anti-Borrelia sp. in schizophrenic patients. This case-control study included 30 schizophrenic patients and 60 healthy individuals. Serological analyses were identified by using ELISA technique. In the case group the Toxoplasma seropositivity was 33.3% and Borrelia seropositivity was 13.3%, while in the control group the Toxoplasma positivity was 21.7% and Borrelia seropositivity was 15.0%. There was no significant difference with regard to seroprevalence between the groups (P = 0.232; P = 0.832, respectively). There was statistically significant difference between case and control groups related to hand and kitchen utensil hygiene after dealing with raw meat (P = 0.001). Our data showed the rate of Toxoplasma antibodies was higher in the case group, while the rate of Borrelia antibodies was higher in the control group. In both groups the high rates of seropositivity for Toxoplasma gondii and Borrelia sp. is thought to be due to neglect of personal hygiene. The present study also is the first to examine the association between Borrelia sp. and schizophrenia. Further studies are needed to determine whether there is an association between Borrelia sp. and schizophrenia or not.

  1. Heterolytic cleavage of ammonia N-H bond by bifunctional activation in silica-grafted single site Ta(V) imido amido surface complex. Importance of the outer sphere NH3 assistance

    KAUST Repository

    Gouré, Eric

    2011-01-01

    Ammonia N-H bond is cleaved at room temperature by the silica-supported tantalum imido amido complex [(≡SiO)2Ta(NH)(-NH2)], 2, if excess ammonia is present, but requires 150 °C to achieve the same reaction if only one equivalent NH3 is added to 2. MAS solid-state 15N NMR and in situ IR spectroscopic studies of the reaction of either 15N or 2H labeled ammonia with 2 show that initial coordination of the ammonia is followed by scrambling of either 15N or 2H among ammonia, amido and imido groups. Density functional theory (DFT) calculations with a cluster model [{(μ-O)[(H3SiO) 2SiO]2}Ta(NH)(-NH2)(NH3)], 2 q·NH3, show that the intramolecular H transfer from Ta-NH2 to TaNH is ruled out, but the H transfers from the coordinated ammonia to the amido and imido groups have accessible energy barriers. The energy barrier for the ammonia N-H activation by the Ta-amido group is energetically preferred relative to the Ta-imido group. The importance of excess NH3 for getting full isotope scrambling is rationalized by an outer sphere assistance of ammonia acting as proton transfer agent, which equalizes the energy barriers for H transfer from coordinated ammonia to the amido and imido groups. In contrast, additional coordinated ammonia does not favor significantly the H transfer. These results rationalize the experimental conditions used. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2011.

  2. Establishment of a minor groove binder-probe based quantitative real time PCR to detect Borrelia burgdorferi sensu lato and differentiation of Borrelia spielmanii by ospA-specific conventional PCR

    Directory of Open Access Journals (Sweden)

    Strube Christina

    2010-08-01

    Full Text Available Abstract Background Borrelia burgdorferi sensu lato (sl, the causative agent of Lyme borreliosis, is transmitted by ticks of the genus Ixodes as vector. For identification of Borrelia infections in ticks a TaqMan™ minor groove binder (MGB probe-based quantitative real time PCR (qPCR was established targeting the 5S-23S intergenic spacer. Extension to a duplex qPCR included an Ixodes spp. positive control to verify successful DNA isolation. Besides qPCR, an ospA-specific conventional PCR for species-specific identification of B. spielmanii was established. Afterwards 1000 I. ricinus flagged in the city of Hanover, Germany, were investigated for B. burgdorferi sl infections followed by species identification. Furthermore, I. hexagonus ticks were investigated to proof applicability of the PCRs. Results Quantitative real time PCR (qPCR identifying B. burgdorferi sl in ticks was able to detect 1-10 copies per reaction. B. spielmanii ospA-specific conventional PCR was also highly specific and showed no cross reactions with the other tested Borrelia species. From 1000 hanoveranian ticks 24.3% were positive compared to only 7.4% positives by dark-field microscopy. Related to tick stage 1.7% larvae, 18.1% nymphs, and 34.6% adults were positive. The most frequent species was B. garinii, followed by B. afzelii, B. spielmanii, B. valaisiana and B. burgdorferi sensu stricto (ss. 70.6% of I. ricinus were mono-infected, whereas 28.0% and 1.4% were infected with two and three Borrelia species, respectively. From 232 I. hexagonus collected from hedgehogs in different sites of Germany, qPCR detected 5.7% to be infected with B. burgdorferi sl, which were identified as B. afzelii, B. garinii and B. spielmanii. Conclusions The evaluated qPCR to detect B. burgdorferi sl in Ixodes spp. is highly specific and sensitive. As a duplex qPCR including detection of Ixodes spp. DNA it is the first DNA based technique incorporating a control for successful DNA isolation from

  3. Tick Thioester-Containing Proteins and Phagocytosis Do Not Affect Transmission of Borrelia afzelii from the Competent Vector Ixodes ricinus

    Czech Academy of Sciences Publication Activity Database

    Urbanová, V.; Hajdušek, O.; Hönig Mondeková, Helena; Šíma, R.; Kopáček, P.

    2017-01-01

    Roč. 7, MAR 16 (2017), s. 1-16, č. článku 73. ISSN 2235-2988 Institutional support: RVO:61388971 Keywords : Borrelia * complement * phagocytosis Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.300, year: 2016

  4. Seroprevalence of Borrelia burgdorferi sensu lato and tick-borne encephalitis virus in zoo animal species in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Širmarová, J.; Tichá, L.; Golovchenko, Maryna; Salát, Jiří; Grubhoffer, L.; Rudenko, Natalia; Nowotny, N.; Růžek, Daniel

    2014-01-01

    Roč. 5, č. 5 (2014), s. 523-527 ISSN 1877-959X R&D Projects: GA ČR GAP502/11/2116 Institutional support: RVO:60077344 Keywords : Tick-borne encephalitis virus * Borrelia burgdorferi sensu lato * Lyme borreliosis * Seroprevalence * Zoo animals Subject RIV: EE - Microbiology, Virology Impact factor: 2.718, year: 2014

  5. Isolation, cultivation and identification of Borrelia burgdorferi genospecies from Ixodes ricinus ticks from the city of Brno, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Pejchalová, K.; Žákovská, A.; Mejzlíková, M.; Halouzka, Jiří; Dendis, M.

    2007-01-01

    Roč. 14, č. 1 (2007), s. 75-79 ISSN 1232-1966 Institutional research plan: CEZ:AV0Z60930519 Keywords : Borrelia burgdorferi * cultivation * DFM method * Ixodes ricinus * Lyme Subject RIV: EE - Microbiology, Virology Impact factor: 1.074, year: 2007 http://www.aaem.pl/pdf/1475.pdf

  6. A tick gut protein with fibronectin III domains aids Borrelia burgdorferi congregation to the gut during transmission

    NARCIS (Netherlands)

    Narasimhan, Sukanya; Coumou, Jeroen; Schuijt, Tim J.; Boder, Eric; Hovius, Joppe W.; Fikrig, Erol

    2014-01-01

    Borrelia burgdorferi transmission to the vertebrate host commences with growth of the spirochete in the tick gut and migration from the gut to the salivary glands. This complex process, involving intimate interactions of the spirochete with the gut epithelium, is pivotal to transmission. We utilized

  7. First detection of Borrelia burgdorferi sensu lato DNA in king penguins (Aptenodytes patagonicus halli).

    Science.gov (United States)

    Schramm, Frédéric; Gauthier-Clerc, Michel; Fournier, Jean-Charles; McCoy, Karen D; Barthel, Cathy; Postic, Danièle; Handrich, Yves; Le Maho, Yvon; Jaulhac, Benoît

    2014-10-01

    The hard tick Ixodes uriae parasitises a wide range of seabird species in the circumpolar areas of both Northern and Southern hemispheres and has been shown to be infected with Borrelia burgdorferi sensu lato, the bacterial agents of Lyme borreliosis. Although it is assumed that seabirds represent viable reservoir hosts, direct demonstrations of infection are limited to a single study from the Northern hemisphere. Here, the blood of 50 tick-infested adult king penguins (Aptenodytes patagonicus halli) breeding in the Crozet Archipelago (Southern Indian Ocean) was examined for B. burgdorferi sl exposure by serology and for spirochetemia by in vitro DNA amplification. Four birds were found positive by serology, whereas B. burgdorferi sl DNA was detected in two other birds. Our data therefore provide the first direct proof of Borrelia burgdorferi sl spirochetes in seabirds of the Southern hemisphere and indicate a possible reservoir role for king penguins in the natural maintenance of this bacterium. Although the bacterial genetic diversity present in these hosts and the infectious period for tick vectors remain to be elucidated, our results add to a growing body of knowledge on the contribution of seabirds to the complex epizootiology of Lyme disease and the global dissemination of B. burgdorferi sl spirochetes. Copyright © 2014 Elsevier GmbH. All rights reserved.

  8. Refractoriness of the western fence lizard (Sceloporus occidentalis) to the Lyme disease group spirochete Borrelia bissettii.

    Science.gov (United States)

    Lane, R S; Mun, J; Eisen, L; Eisen, R J

    2006-08-01

    The western fence lizard, Sceloporus occidentalis, is refractory to experimental infection with Borrelia burgdorferi sensu stricto, one of several Lyme disease spirochetes pathogenic for humans. Another member of the Lyme disease spirochete complex, Borrelia bissettii, is distributed widely throughout North America and a similar, if not identical, spirochete has been implicated as a human pathogen in southern Europe. To determine the susceptibility of S. occidentalis to B. bissettii, 6 naïve lizards were exposed to the feeding activities of Ixodes pacificus nymphs experimentally infected with this spirochete. None of the lizards developed spirochetemias detectable by polymerase chain reaction for up to 8 wk post-tick feeding, infected nymphs apparently lost their B. bissettii infections within 1-2 wk after engorgement, and xenodiagnostic L. pacificus larvae that co-fed alongside infected nymphs did not acquire and maintain spirochetes. In contrast, 3 of 4 naïve deer mice (Peromyscus maniculatus) exposed similarly to feeding by 1 or more B. bissettii-infected nymphs developed patent infections within 4 wk. These and previous findings suggest that the complement system of S. occidentalis typically destroys B. burgdorferi sensu lato spirochetes present in tissues of attached and feeding I. pacificus nymphs, thereby potentially reducing the probability of transmission of these bacteria to humans or other animals by the resultant adult ticks.

  9. Seroprevalence against Rickettsia and Borrelia Species in Patients with Uveitis: A Prospective Survey

    Directory of Open Access Journals (Sweden)

    Kim B. Madsen

    2017-01-01

    Full Text Available Vector-borne diseases such as Lyme borreliosis and rickettsioses have been associated with ocular inflammation. Our aim was to study patients with diagnosed uveitis to evaluate serological signs of infection or exposure to these tick-borne agents. Forty-eight patients were prospectively examined with serology together with medical records and a questionnaire concerning previous exposure, diseases, and treatments. Seven patients (14.6% showed seroconversion to Rickettsia spp. between acute and convalescent phase sera, which provides support for a positive Rickettsia diagnosis according to guidelines. The specificity was confirmed by Western blot. Additional 28 patients had stationary titres of which eight (16.6% had 1 : 256 or higher titre in the first serum, and another 13 patients were seronegative. No epidemiological risk factor or marker could be identified. For Borrelia, only three patients showed moderate IgG titres. A control group of 100 blood donors, 60 patients with rheumatic disease, and 56 patients seeking medical care were tested of which 2.0–7.1% showed low anti-Rickettsia titres and 3.0–8.3% anti-Borrelia titres. The findings are indicative for an association between infection or exposure to Rickettsia spp. and uveitis with a seropositivity among patients with recurrent uveitis in concordance with the spread of rickettsial exposure in a tick-exposed population.

  10. Seroprevalence against Rickettsia and Borrelia Species in Patients with Uveitis: A Prospective Survey

    Science.gov (United States)

    Madsen, Kim B.; Wallménius, Katarina; Fridman, Åke; Påhlson, Carl

    2017-01-01

    Vector-borne diseases such as Lyme borreliosis and rickettsioses have been associated with ocular inflammation. Our aim was to study patients with diagnosed uveitis to evaluate serological signs of infection or exposure to these tick-borne agents. Forty-eight patients were prospectively examined with serology together with medical records and a questionnaire concerning previous exposure, diseases, and treatments. Seven patients (14.6%) showed seroconversion to Rickettsia spp. between acute and convalescent phase sera, which provides support for a positive Rickettsia diagnosis according to guidelines. The specificity was confirmed by Western blot. Additional 28 patients had stationary titres of which eight (16.6%) had 1 : 256 or higher titre in the first serum, and another 13 patients were seronegative. No epidemiological risk factor or marker could be identified. For Borrelia, only three patients showed moderate IgG titres. A control group of 100 blood donors, 60 patients with rheumatic disease, and 56 patients seeking medical care were tested of which 2.0–7.1% showed low anti-Rickettsia titres and 3.0–8.3% anti-Borrelia titres. The findings are indicative for an association between infection or exposure to Rickettsia spp. and uveitis with a seropositivity among patients with recurrent uveitis in concordance with the spread of rickettsial exposure in a tick-exposed population. PMID:29318041

  11. Positive IgG Western Blot for Borrelia burgdorferi in Colombia

    Directory of Open Access Journals (Sweden)

    Palacios Ricardo

    1999-01-01

    Full Text Available In order to evaluate the presence of specific IgG antibodies to Borrelia burgdorferi in patients with clinical manifestations associated with Lyme borreliosis in Cali, Colombia, 20 serum samples from patients with dermatologic signs, one cerebrospinal fluid (CSF sample from a patient with chronic neurologic and arthritic manifestations, and twelve serum samples from individuals without clinical signs associated with Lyme borreliosis were analyzed by IgG Western blot. The results were interpreted following the recommendations of the Centers for Diseases Control and Prevention (CDC for IgG Western blots. Four samples fulfilled the CDC criteria: two serum specimens from patients with morphea (localized scleroderma, the CSF from the patient with neurologic and arthritic manifestations, and one of the controls. Interpretation of positive serology for Lyme disease in non-endemic countries must be cautious. However these results suggest that the putative "Lyme-like" disease may correlate with positivity on Western blots, thus raising the possibility that a spirochete genospecies distinct from B. burgdorferi sensu stricto, or a Borrelia species other than B. burgdorferi sensu lato is the causative agent. Future work will focus on a survey of the local tick and rodent population for evidence of spirochete species that could be incriminated as the etiologic agent.

  12. Fatal spirochetosis due to a relapsing fever-like Borrelia sp. in northern spotted owl

    Science.gov (United States)

    Thomas, N.J.; Bunikis, J.; Barbour, A.G.; Wolcott, M.J.

    2002-01-01

    Acute septicemic spirochetosis was diagnosed in an adult male northern spotted owl (Strix occidentalis caurina) found dead in Kittitas County, Washington, USA. Gross necropsy findings included marked enlargement of the liver and spleen and serofibrinous deposits on the serous membranes lining the body cavities and the pericardial and perihepatic sacs. Microscopic observations included macrophage infiltration in the liver and spleen with mild thrombosis and multifocal necrosis, as well as hemorrhage and acute inflammation in the choroid plexus of the brain. No viruses or pathogenic bacteria were isolated from brain, liver, or spleen, and no parasites were found in blood smears or impression smears of the liver. Chlamydial culture attempts were unsuccessful and no chlamydial antibodies were detected in serum. In silver-stained microscopic sections and by transmission electron microscopy of liver, numerous long, thin, spiral-shaped bacteria were seen in the liver, spleen, cerebral ventricles, and within blood vessels in many organs. The organism was identified as a member of the Borrelia genus by sequence analysis of the PCR-amplified 16S rRNA gene. The most closely related species is B. hermsii, an agent of relapsing fever in humans in the western United States. This is the first report of a relapsing fever-related Borrelia in a wild bird.

  13. Improved method of measurement for outer leak

    International Nuclear Information System (INIS)

    Xu Guang

    2012-01-01

    Pneumatic pipeline is installed for the airborne radioactivity measurement equipment, air tightness and outer leak rate are essential for the testing of the characteristics, both in the national criteria and ISO standards, an improved practical method is available for the measurement of the outer air leak rate based on the engineering experiences for the equipment acceptance and testing procedure. (authors)

  14. Survey of Borreliae in ticks, canines, and white-tailed deer from Arkansas, U.S.A.

    Directory of Open Access Journals (Sweden)

    Fryxell Rebecca T

    2012-07-01

    Full Text Available Abstract Background In the Eastern and Upper Midwestern regions of North America, Ixodes scapularis (L. is the most abundant tick species encountered by humans and the primary vector of B. burgdorferi, whereas in the southeastern region Amblyomma americanum (Say is the most abundant tick species encountered by humans but cannot transmit B. burgdorferi. Surveys of Borreliae in ticks have been conducted in the southeastern United States and often these surveys identify B. lonestari as the primary Borrelia species, surveys have not included Arkansas ticks, canines, or white-tailed deer and B. lonestari is not considered pathogenic. The objective of this study was to identify Borrelia species within Arkansas by screening ticks (n = 2123, canines (n = 173, and white-tailed deer (n = 228 to determine the identity and locations of Borreliae endemic to Arkansas using PCR amplification of the flagellin (flaB gene. Methods Field collected ticks from canines and from hunter-killed white-tailed were identified to species and life stage. After which, ticks and their hosts were screened for the presence of Borrelia using PCR to amplify the flaB gene. A subset of the positive samples was confirmed with bidirectional sequencing. Results In total 53 (21.2% white-tailed deer, ten (6% canines, and 583 (27.5% Ixodid ticks (252 Ixodes scapularis, 161 A. americanum, 88 Rhipicephalus sanguineus, 50 Amblyomma maculatum, 19 Dermacentor variabilis, and 13 unidentified Amblyomma species produced a Borrelia flaB amplicon. Of the positive ticks, 324 (22.7% were collected from canines (151 A. americanum, 78 R. sanguineus, 43 I. scapularis, 26 A. maculatum, 18 D. variabilis, and 8 Amblyomma species and 259 (37.2% were collected from white-tailed deer (209 I. scapularis, 24 A. maculatum, 10 A. americanum, 10 R. sanguineus, 1 D. variabilis, and 5 Amblyomma species. None of the larvae were PCR positive. A majority of the flaB amplicons were homologous with B

  15. Mapping of the seasonal dynamic properties of building walls in actual periodic conditions and effects produced by solar radiation incident on the outer and inner surfaces of the wall

    International Nuclear Information System (INIS)

    Mazzeo, D.; Oliveti, G.; Arcuri, N.

    2016-01-01

    Highlights: • Dynamic thermal behaviour of building walls subjected to actual periodic loadings. • Dynamic parameters of wall in terms of energy and of heat flux are defined. • Different solar absorption coefficients and orientations of wall are considered. • On the internal surface is present or absent a shortwave radiant field. • Seasonal thermal characteristics for different plant operating regime are provided. - Abstract: In this work, the dynamic characteristics of the external walls of air-conditioned buildings subject to the joint action of periodic non-sinusoidal external and internal loadings are determined. The dynamic parameters used are the energy decrement factor, which is evaluated by means of the fluctuating heat flux in a semi-period exiting and entering the wall, the decrement factor of the maximum peak and minimum peak of the heat flux in a period and the relative time lags. The fluctuating heat flux in the wall in steady periodic regime conditions is determined with an analytical model obtained by resolving the equivalent electrical circuit. The preceding parameters are used for a study of the influence of solar radiation on the dynamic characteristics of the walls in summer and winter air-conditioning. Solar radiation is considered as operating on the external surface and on the internal surface due to the presence in the indoor environments of a shortwave radiant field. The absorbed solar heat flux by the external surface varies, modifying the solar absorption coefficient and wall orientation. Indoors, we considered a continuous operating regime of the plant and a regime with nocturnal attenuation. The results obtained, relating to 1152 different boundary conditions, were used for the construction of maps of dynamic characteristics, different on variation of the plant functioning regime and of the shortwave radiant load on the internal surface. The maps show the dependence of the decrement factors and of the time lags on variation of

  16. Incorporation of squalene into rod outer segments

    International Nuclear Information System (INIS)

    Keller, R.K.; Fliesler, S.J.

    1990-01-01

    We have reported previously that squalene is the major radiolabeled nonsaponifiable lipid product derived from [ 3 H]acetate in short term incubations of frog retinas. In the present study, we demonstrate that newly synthesized squalene is incorporated into rod outer segments under similar in vitro conditions. We show further that squalene is an endogenous constituent of frog rod outer segment membranes; its concentration is approximately 9.5 nmol/mumol of phospholipid or about 9% of the level of cholesterol. Pulse-chase experiments with radiolabeled precursors revealed no metabolism of outer segment squalene to sterols in up to 20 h of chase. Taken together with our previous absolute rate studies, these results suggest that most, if not all, of the squalene synthesized by the frog retina is transported to rod outer segments. Synthesis of protein is not required for squalene transport since puromycin had no effect on squalene incorporation into outer segments. Conversely, inhibition of isoprenoid synthesis with mevinolin had no effect on the incorporation of opsin into the outer segment. These latter results support the conclusion that the de novo synthesis and subsequent intracellular trafficking of opsin and isoprenoid lipids destined for the outer segment occur via independent mechanisms

  17. Small RNAs controlling outer membrane porins

    DEFF Research Database (Denmark)

    Valentin-Hansen, Poul; Johansen, Jesper; Rasmussen, Anders A

    2007-01-01

    are key regulators of environmental stress. Recent work has revealed an intimate interplay between small RNA regulation of outer membrane proteins and the stress-induced sigmaE-signalling system, which has an essential role in the maintenance of the integrity of the outer membrane.......Gene regulation by small non-coding RNAs has been recognized as an important post-transcriptional regulatory mechanism for several years. In Gram-negative bacteria such as Escherichia coli and Salmonella, these RNAs control stress response and translation of outer membrane proteins and therefore...

  18. Outer brain barriers in rat and human development

    DEFF Research Database (Denmark)

    Brøchner, Christian B; Holst, Camilla Bjørnbak; Møllgård, Kjeld

    2015-01-01

    Complex barriers at the brain's surface, particularly in development, are poorly defined. In the adult, arachnoid blood-cerebrospinal fluid (CSF) barrier separates the fenestrated dural vessels from the CSF by means of a cell layer joined by tight junctions. Outer CSF-brain barrier provides...... diffusion restriction between brain and subarachnoid CSF through an initial radial glial end feet layer covered with a pial surface layer. To further characterize these interfaces we examined embryonic rat brains from E10 to P0 and forebrains from human embryos and fetuses (6-21st weeks post...

  19. Automated purification of Borrelia burgdorferi s.l. PCR products with KingFisherTM magnetic particle processor prior to genome sequencing

    International Nuclear Information System (INIS)

    Maekinen, Johanna; Marttila, Harri; Viljanen, Matti K.

    2001-01-01

    Borrelia burgdorferi sensu lato genospecies were differentiated by PCR-based sequencing of the borrelial flagellin gene. To evaluate the usefulness of KingFisher TM magnetic particle processor in PCR product purification, borrelia PCR products were purified with KingFisher TM magnetic particle processor prior to cycle sequencing and the quality of the sequence data received was analyzed. KingFisher was found to offer a rapid and reliable alternative for borrelial PCR product purification

  20. Abundance of Ixodes ricinus and prevalence of Borrelia burgdorferi s.l. in the nature reserve Siebengebirge, Germany, in comparison to three former studies from 1978 onwards

    Czech Academy of Sciences Publication Activity Database

    Schwarz, Alexandra; Hönig, Václav; Vavrušková, Zuzana; Grubhoffer, Libor; Balczun, C.; Albring, A.; Schaub, G. A.

    2012-01-01

    Roč. 5, NOV 21 (2012) ISSN 1756-3305 R&D Projects: GA ČR GD206/09/H026; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Ixodes ricinus * Tick density * Borrelia prevalence * Borrelia lusitaniae * Multiple infections * Siebengebirge Subject RIV: EC - Immunology Impact factor: 3.246, year: 2012 http://www.parasitesandvectors.com/content/5/1/268

  1. Students’ misconceptions about Newton's second law in outer space

    International Nuclear Information System (INIS)

    Temiz, B K; Yavuz, A

    2014-01-01

    Students’ misconceptions about Newton's second law in frictionless outer space were investigated. The research was formed according to an epistemic game theoretical framework. The term ‘epistemic’ refers to students’ participation in problem-solving activities as a means of constructing new knowledge. The term ‘game’ refers to a coherent activity that consists of moves and rules. A set of questions in which students are asked to solve two similar Newton's second law problems, one of which is on the Earth and the other in outer space, was administered to 116 undergraduate students. The findings indicate that there is a significant difference between students’ epistemic game preferences and race-type (outer space or frictional surface) question. So students who used Newton's second law on the ground did not apply this law and used primitive reasoning when it came to space. Among these students, voluntary interviews were conducted with 18 students. Analysis of interview transcripts showed that: (1) the term ‘space’ causes spontaneity among students that prevents the use of the law; (2) students hesitate to apply Newton's second law in space due to the lack of a condition—the friction; (3) students feel that Newton's second law is not valid in space for a variety of reasons, but mostly for the fact that the body in space is not in contact with a surface. (paper)

  2. Structure-function mapping of BbCRASP-1, the key complement factor H and FHL-1 binding protein of Borrelia burgdorferi.

    Science.gov (United States)

    Cordes, Frank S; Kraiczy, Peter; Roversi, Pietro; Simon, Markus M; Brade, Volker; Jahraus, Oliver; Wallis, Russell; Goodstadt, Leo; Ponting, Chris P; Skerka, Christine; Zipfel, Peter F; Wallich, Reinhard; Lea, Susan M

    2006-05-01

    Borrelia burgdorferi, a spirochaete transmitted to human hosts during feeding of infected Ixodes ticks, is the causative agent of Lyme disease, the most frequent vector-borne disease in Eurasia and North America. Sporadically Lyme disease develops into a chronic, multisystemic disorder. Serum-resistant B. burgdorferi strains bind complement factor H (FH) and FH-like protein 1 (FHL-1) on the spirochaete surface. This binding is dependent on the expression of proteins termed complement-regulator acquiring surface proteins (CRASPs). The atomic structure of BbCRASP-1, the key FHL-1/FH-binding protein of B. burgdorferi, has recently been determined. Our analysis indicates that its protein topology apparently evolved to provide a high affinity interaction site for FH/FHL-1 and leads to an atomic-level hypothesis for the functioning of BbCRASP-1. This work demonstrates that pathogens interact with complement regulators in ways that are distinct from the mechanisms used by the host and are thus obvious targets for drug design.

  3. Serodiagnosis of Borrelia miyamotoi disease by measuring antibodies against GlpQ and variable major proteins

    DEFF Research Database (Denmark)

    Koetsveld, J.; Kolyasnikova, N. M.; Wagemakers, A.

    2018-01-01

    previously shown the differential expression of antigenic variable major proteins (Vmps) in B. miyamotoi, our aim was to study antibody responses against GlpQ and Vmps in PCR-proven BMD patients and controls. Methods: We assessed seroreactivity against GlpQ and four Vmps in a well-described, longitudinal......, and IgG between 21 and 50 days, after disease onset. Various combinations of GlpQ and Vmps increased sensitivity and/or specificity compared to single antigens. Notably, the GlpQ or variable large protein (Vlp)-15/16 combination yielded a sensitivity of 94.7% (95% CI: 75.4–99.7) 11–20 days after disease......Objectives: Borrelia miyamotoi disease (BMD) is an emerging tick-borne disease in the Northern hemisphere. Serodiagnosis by measuring antibodies against glycerophosphodiester-phosphodiesterase (GlpQ) has been performed experimentally but has not been extensively clinically validated. Because we had...

  4. Borrelia miyamotoi, Other Vector-Borne Agents in Cat Blood and Ticks in Eastern Maryland.

    Science.gov (United States)

    Shannon, Avery B; Rucinsky, Renee; Gaff, Holly D; Brinkerhoff, R Jory

    2017-12-01

    We collected blood and tick samples in eastern Maryland to quantify vector-borne pathogen exposure and infection in healthy cats and to assess occupational disease risk to veterinary professionals and others who regularly interact with household pets. Thirty-six percent of healthy cats parasitized by ticks at time of examination (9/25) were exposed to, and 14% of bloods (7/49) tested PCR-positive for, at least one vector-borne pathogen including several bloods and ticks with Borrelia miyamotoi, a recently recognized tick-borne zoonotic bacterium. There was no indication that high tick burdens were associated with exposure to vector-borne pathogens. Our results underscore the potential importance of cats to human vector-borne disease risk.

  5. Increasing RpoS expression causes cell death in Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Linxu Chen

    Full Text Available RpoS, one of the two alternative σ factors in Borrelia burgdorferi, is tightly controlled by multiple regulators and, in turn, determines expression of many critical virulence factors. Here we show that increasing RpoS expression causes cell death. The immediate effect of increasing RpoS expression was to promote bacterial division and as a consequence result in a rapid increase in cell number before causing bacterial death. No DNA fragmentation or degradation was observed during this induced cell death. Cryo-electron microscopy showed induced cells first formed blebs, which were eventually released from dying cells. Apparently blebbing initiated cell disintegration leading to cell death. These findings led us to hypothesize that increasing RpoS expression triggers intracellular programs and/or pathways that cause spirochete death. The potential biological significance of induced cell death may help B. burgdorferi regulate its population to maintain its life cycle in nature.

  6. Polymerase chain reaction in diagnosis of Borrelia burgdorferi infections and studies on taxonomic classification

    DEFF Research Database (Denmark)

    Lebech, Anne-Mette

    2002-01-01

    Lyme borreliosis caused by the spirochete Borrelia burgdorferi is now the most common vectorborne disease in North America, Europe and Asia. It is a multisystemic infection which may cause skin, neurological, cardiac or rheumatologic disorders. The aims of the present thesis were: (i) to develop...... and different clinical presentations (dermatoborreliosis versus neuroborreliosis) and courses (self-limiting versus chronic disease). Furthermore, strain differences were of importance for selection of suitable antigens for diagnostic assays and for vaccine development. Since then, B. burgdorferi isolates have...... a histological B. burgdorferi specific immunophosphatase-staining method. The utility of the PCR was then tested for identification of B. burgdorferi DNA in skin biopsies from 31 patients with erythema migrans. The sensitivity of PCR was 71%, which was superior to culture and serology. Based on own and otherwise...

  7. Borrelia burgdorferi Infection and Lyme Disease in North American Horses: A Consensus Statement

    Science.gov (United States)

    Gardner, R.B.; Madigan, J.E.; Witonsky, S.G.; Bertone, J.J.; Swinebroad, E.L.; Schutzer, S.E.; Johnson, A.L.

    2018-01-01

    Borrelia burgdorferi infection is common in horses living in Lyme endemic areas and the geographic range for exposure is increasing. Morbidity after B. burgdorferi infection in horses is unknown. Documented, naturally occurring syndromes attributed to B. burgdorferi infection in horses include neuroborreliosis, uveitis, and cutaneous pseudolymphoma. Although other clinical signs such as lameness and stiffness are reported in horses, these are often not well documented. Diagnosis of Lyme disease is based on exposure to B. burgdorferi, cytology or histopathology of infected fluid or tissue and antigen detection. Treatment of Lyme disease in horses is similar to treatment of humans or small animals but treatment success might not be the same because of species differences in antimicrobial bioavailability and duration of infection before initiation of treatment. There are no approved equine label Lyme vaccines but there is strong evidence that proper vaccination could prevent infection in horses. PMID:29469222

  8. Borrelia burgdorferi antibodies in dogs from Cotia county, São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    JOPPERT Adriana Marques

    2001-01-01

    Full Text Available Dogs sera samples collected from Cotia County, São Paulo were tested using indirect immunoenzymatic test (ELISA in order to study Lyme disease serology in dogs. ELISA method was standardized and G39/40 North American strain of Borrelia burgdorferi was used as antigen. Positive results were confirmed employing the Western blotting technique. Because of the possibility of cross-reactions, sera were also tested for different serological strains of Leptospira interrogans and L. biflexa using microscopic sera agglutination test. Twenty-three of 237 (9.7% serum samples were positive in the ELISA; 20 of them (86.9% were confirmed by the Western blotting, what suggests that Cotia may be a risk area for Lyme disease. Although 4 samples (1.7% were positive for Lyme disease and leptospirosis, no correlation was found between the results (X² = 0.725; p = 0.394 what suggests absence of serological cross reactivity.

  9. Genome Stability of Lyme Disease Spirochetes: Comparative Genomics of Borrelia burgdorferi Plasmids

    Energy Technology Data Exchange (ETDEWEB)

    Casjens S. R.; Dunn J.; Mongodin, E. F.; Qiu, W.-G.; Luft, B. J.; Schutzer, S. E.; Gilcrease, E. B.; Huang, W. M.; Vujadinovic, M.; Aron, J. K.; Vargas, L. C.; Freeman, S.; Radune, D.; Weidman, J. F.; Dimitrov, G. I.; Khouri, H. M.; Sosa, J. E.; Halpin, R. A.; Fraser, C. M.

    2012-03-14

    Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33-40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi {approx}900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short {le}20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant.

  10. Complement-mediated killing of Borrelia burgdorferi by nonimmune sera from sika deer.

    Science.gov (United States)

    Nelson, D R; Rooney, S; Miller, N J; Mather, T N

    2000-12-01

    Various species of cervid deer are the preferred hosts for adult, black-legged ticks (Ixodes scapularis and Ixodes pacificus) in the United States. Although frequently exposed to the agent of Lyme disease (Borrelia burgdorferi), these animals, for the most part, are incompetent as transmission reservoirs. We examined the borreliacidal activity of normal and B. burgdorferi-immune sera from sika deer (Cervus nippon) maintained in a laboratory setting and compared it to that of similar sera from reservoir-competent mice and rabbits. All normal deer sera (NDS) tested killed > 90% of B. burgdorferi cells. In contrast, normal mouse and rabbit sera killed feeding exhibited IFA titers of 1:256, whereas sera from mice and rabbits similarly exposed had titers of > 1:1,024. Heat treatment (56 C, 30 min) of NDS reduced borreliacidal activity, with complement-mediated killing. The chelators EGTA and EDTA were used to block the classical or both the classical and alternative complement pathways, respectively. Addition of 10 mM EGTA to NDS had a negligible effect on borreliacidal activity, with > 90% of the cells killed. Addition of 10 mM EDTA reduced the killing to approximately 30%, whereas the addition of Mg2+ (10 mM) restored borreliacidal activity to NDS. The addition of zymosan A, an activator of the alternative pathway, increased the survival of B. burgdorferi cells to approximately 80% in NDS. These data suggest that the alternative complement activation pathway plays a major role in the borreliacidal activity of NDS. Additionally, 10 mM EGTA had almost no effect on the killing activity of B. burgdorferi-exposed deer sera, suggesting that the classical pathway is not involved in Borrelia killing, even in sera from B. burgdorferi-exposed deer.

  11. An Ixodes ricinus Tick Salivary Lectin Pathway Inhibitor Protects Borrelia burgdorferi sensu lato from Human Complement.

    Science.gov (United States)

    Wagemakers, Alex; Coumou, Jeroen; Schuijt, Tim J; Oei, Anneke; Nijhof, Ard M; van 't Veer, Cornelis; van der Poll, Tom; Bins, Adriaan D; Hovius, Joppe W R

    2016-04-01

    We previously identified tick salivary lectin pathway inhibitor (TSLPI) in Ixodes scapularis, a vector for Borrelia burgdorferi sensu stricto (s.s.) in North America. TSLPI is a salivary protein facilitating B. burgdorferi s.s. transmission and acquisition by inhibiting the host lectin complement pathway through interference with mannose binding lectin (MBL) activity. Since Ixodes ricinus is the predominant vector for Lyme borreliosis in Europe and transmits several complement sensitive B. burgdorferi sensu lato (s.l.) strains, we aimed to identify, describe, and characterize the I. ricinus ortholog of TSLPI. We performed (q)PCRs on I. ricinus salivary gland cDNA to identify a TSLPI ortholog. Next, we generated recombinant (r)TSLPI in a Drosophila expression system and examined inhibition of the MBL complement pathway and complement-mediated killing of B. burgdorferi s.l. in vitro. We identified a TSLPI ortholog in I. ricinus salivary glands with 93% homology at the RNA and 89% at the protein level compared to I. scapularis TSLPI, which was upregulated during tick feeding. In silico analysis revealed that TSLPI appears to be part of a larger family of Ixodes salivary proteins among which I. persulcatus basic tail salivary proteins and I. scapularis TSLPI and Salp14. I. ricinus rTSLPI inhibited the MBL complement pathway and protected B. burgdorferi s.s. and Borrelia garinii from complement-mediated killing. We have identified a TSLPI ortholog, which protects B. burgdorferi s.l. from complement-mediated killing in I. ricinus, the major vector for tick-borne diseases in Europe.

  12. Outer Magnetospheric Boundaries Cluster Results

    CERN Document Server

    Paschmann, Goetz; Schwartz, S J

    2006-01-01

    When the stream of plasma emitted from the Sun (the solar wind) encounters Earth's magnetic field, it slows down and flows around it, leaving behind a cavity, the magnetosphere. The magnetopause is the surface that separates the solar wind on the outside from the Earth's magnetic field on the inside. Because the solar wind moves at supersonic speed, a bow shock must form ahead of the magnetopause that acts to slow the solar wind to subsonic speeds. Magnetopause, bow shock and their environs are rich in exciting processes in collisionless plasmas, such as shock formation, magnetic reconnection, particle acceleration and wave-particle interactions. They are interesting in their own right, as part of Earth's environment, but also because they are prototypes of similar structures and phenomena that are ubiquitous in the universe, having the unique advantage that they are accessible to in situ measurements. The boundaries of the magnetosphere have been the target of direct in-situ measurements since the beginning ...

  13. Colours of the Outer Solar System Origins Survey: An Update

    Science.gov (United States)

    Schwamb, Megan E.; Fraser, Wesley C.; Pike, Rosemary E.; Bannister, Michele T.; Marsset, Michaël; Kavelaars, J. J.; Benecchi, Susan; Delsanti, Audrey C.; Lehner, Matthew J.; Wang, Shiang-Yu; Thirouin, Audrey; Nesvorný, David

    2018-01-01

    The vast majority of the known dwarf-planet sized bodies are bright enough to be studied through optical and infrared spectroscopy. As a result, we have an understanding of the surface properties for the largest Kuiper belt objects (KBOs) which retain their primordial inventory of volatile ices. For the typically smaller > 22 mag KBO, we must rely instead on what colors reveal by proxy; yet this picture remains incomplete. Most KBO physical property studies examine the hodgepodge set of objects discovered by various surveys with different and varying detection biases that make it difficult if not impossible to reliably estimate the sizes of the different surface color groupings (compositional classes) residing in the modern-day Kuiper belt.The Colours of the Outer Solar System Origins Survey (Col-OSSOS) probes the surface properties within the Kuiper belt primarily through near simultaneous g,r and J colors with the Gemini North Telescope and u-band with Canada-France-Hawaii Telescope. The project aims to target ~100 KBOs brighter than 23.6 r‧ mag found by the Outer Solar System Origins Survey (OSSOS), a survey with a well-measured detection efficiency. Thus, Col-OSSOS provides the first brightness-complete, compositional-dynamical map of the Outer Solar System, probing in a new light the radial color distribution in the primordial planetesimal disk from which KBOs originated. We will provide an update on the current status of the program highlighting results from the first two years of the survey; including size estimates of the two color KBO subgroups (the red and neutral surfaces) within the dynamically excited Kuiper belt and implications for the early planetesimal disk composition based on neutral-colored binaries found in the cold classical Kuiper belt.

  14. Water and Volatiles in the Outer Solar System

    Science.gov (United States)

    Grasset, O.; Castillo-Rogez, J.; Guillot, T.; Fletcher, L. N.; Tosi, F.

    2017-10-01

    Space exploration and ground-based observations have provided outstanding evidence of the diversity and the complexity of the outer solar system. This work presents our current understanding of the nature and distribution of water and water-rich materials from the water snow line to the Kuiper Belt. This synthesis is timely, since a thorough exploration of at least one object in each region of the outer solar system has now been achieved. Next steps, starting with the Juno mission now in orbit around Jupiter, will be more focused on understanding the processes at work than on describing the general characteristics of each giant planet systems. This review is organized in three parts. First, the nature and the distribution of water and volatiles in giant and intermediary planets are described from their inner core to their outer envelopes. A special focus is given to Jupiter and Saturn, which are much better understood than the two ice giants (Uranus and Neptune) thanks to the Galileo and Cassini missions. Second, the icy moons will be discussed. Space missions and ground-based observations have revealed the variety of icy surfaces in the outer system. While Europa, Enceladus, and maybe Titan present past or even active tectonic and volcanic activities, many other moons have been dead worlds for more than 3 billion years. Ice compositions found at these bodies are also complex and it is now commonly admitted that icy surfaces are never composed of pure ices. A detailed review of the distribution of non-ice materials on the surfaces and in the tenuous atmospheres of the moons is proposed, followed by a more focused discussion on the nature and the characteristics of the liquid layers trapped below the cold icy crusts that have been suggested in the icy Galilean moons, and in Enceladus, Dione, and Titan at Saturn. Finally, the recent observations collected by Dawn at Ceres and New Horizons at Pluto, as well as the state of knowledge of other transneptunian objects

  15. Oscillations of the Outer Boundary of the Outer Radiation Belt During Sawtooth Oscillations

    Directory of Open Access Journals (Sweden)

    Jae-Hun Kim

    2006-09-01

    Full Text Available We report three sawtooth oscillation events observed at geosynchronous orbit where we find quasi-periodic (every 2-3 hours sudden flux increases followed by slow flux decreases at the energy levels of ˜50-400 keV. For these three sawtooth events, we have examined variations of the outer boundary of the outer radiation belt. In order to determine L values of the outer boundary, we have used data of relativistic electron flux observed by the SAMPEX satellite. We find that the outer boundary of the outer radiation belt oscillates periodically being consistent with sawtooth oscillation phases. Specifically, the outer boundary of the outer radiation belt expands (namely, the boundary L value increases following the sawtooth particle flux enhancement of each tooth, and then contracts (namely, the boundary L value decreases while the sawtooth flux decreases gradually until the next flux enhancement. On the other hand, it is repeatedly seen that the asymmetry of the magnetic field intensity between dayside and nightside decreases (increases due to the dipolarization (the stretching on the nightside as the sawtooth flux increases (decreases. This implies that the periodic magnetic field variations during the sawtooth oscillations are likely responsible for the expansion-contraction oscillations of the outer boundary of the outer radiation belt.

  16. Detection of Lyme Disease Bacterium, Borrelia burgdorferi sensu lato, in Blacklegged Ticks Collected in the Grand River Valley, Ontario, Canada

    Science.gov (United States)

    Scott, John D.; Foley, Janet E.; Anderson, John F.; Clark, Kerry L.; Durden, Lance A.

    2017-01-01

    We document the presence of blacklegged ticks, Ixodes scapularis, in the Grand River valley, Centre Wellington, Ontario. Overall, 15 (36%) of 42 I. scapularis adults collected from 41 mammalian hosts (dogs, cats, humans) were positive for the Lyme disease bacterium, Borrelia burgdorferi sensu lato (s.l.). Using real-time PCR testing and DNA sequencing of the flagellin (fla) gene, we determined that Borrelia amplicons extracted from I. scapularis adults belonged to B. burgdorferi sensu stricto (s.s.), which is pathogenic to humans and certain domestic animals. Based on the distribution of I. scapularis adults within the river basin, it appears likely that migratory birds provide an annual influx of I. scapularis immatures during northward spring migration. Health-care providers need to be aware that local residents can present with Lyme disease symptoms anytime during the year. PMID:28260991

  17. Cinética do crescimento de Borrelia burgdorferi (Spirochaetaceae em diferentes meios de cultivo Cinetic growth of Borrelia burgdorferi (Spirochaetacease in different culture media

    Directory of Open Access Journals (Sweden)

    Angela de Oliveira

    2004-06-01

    Full Text Available Estudou-se a cinética de crescimento de Borrelia burgdorferi, por um período de 3 meses, utilizando os seguintes oito meios de cultivo : (1 BSK adicionado de soro de coelho, (2 BSK adicionado de soro de suíno, (3 BSK adicionado de soro de suíno + 5 fluorouracil, (4 PMR, (5 CTB, (6 Dubos, (7 Caldo Brucella e (8 BHI. Todos os meios foram preparados assepticamente e mantidos em tubos de ensaio com capacidade para 10 ml. Para cada meio, o inoculo foi padronizado para conter no início 10² espiroquetas para cada 0,1 ml de cultivo. O monitoramento do crescimento foi feito contando-se o total de espiroquetas em 0,1 ml do meio entre lâmina de microscopia e lamínula com dimen sões de 10x30mm, tendo sido utilizado microscópio de campo escuro. A contagem foi realizada durante 14 semanas, tendo sido diária nos primeiros 12 dias e semanal a partir desta data. Houve crescimento de B. burgdorferi em todos meios testados, com melhor performance para três deles: BSK adicionado de soro de coelho, BSK adicionado de soro de suíno + 5 fluorouracil e meio CTB. Observou-se crescimento de B. burgdorferi a partir da 4ª semana, atingindo o platô de crescimento entre a 8ª e 12ª semanas, quando começou a exaustão do meio de cultivo. Formas císticas de B. burgdorferi foram observadas em todos os meios testados.The cinetic of growth of Borrelia burgdorferi was studied during a 3-month period, using the following 8 culture media: (1 rabbit serum BSK, (2 swine serum BSK, (3 swine serum BSK+5 fluorouracil, (4 PMR, (5 CTB, (6 Dubos, (7 Brucella broth and (8 BHI. All media were prepared aseptically and were maintained in culture tubes of 10 ml capacity. For each medium, the inoculum was standardized to contain initially 10² spirochetes for each 0.1 ml of culture. The growth was monitorized by counting the total number of spirochetes in 0.1ml of medium in a dark field microscope, using a 10x30 mm cover slip. For the first 12 days, counting was done each 24

  18. Exploring the association between Morgellons disease and Lyme disease: identification of Borrelia burgdorferi in Morgellons disease patients.

    Science.gov (United States)

    Middelveen, Marianne J; Bandoski, Cheryl; Burke, Jennie; Sapi, Eva; Filush, Katherine R; Wang, Yean; Franco, Agustin; Mayne, Peter J; Stricker, Raphael B

    2015-02-12

    Morgellons disease (MD) is a complex skin disorder characterized by ulcerating lesions that have protruding or embedded filaments. Many clinicians refer to this condition as delusional parasitosis or delusional infestation and consider the filaments to be introduced textile fibers. In contrast, recent studies indicate that MD is a true somatic illness associated with tickborne infection, that the filaments are keratin and collagen in composition and that they result from proliferation and activation of keratinocytes and fibroblasts in the skin. Previously, spirochetes have been detected in the dermatological specimens from four MD patients, thus providing evidence of an infectious process. Based on culture, histology, immunohistochemistry, electron microscopy and molecular testing, we present corroborating evidence of spirochetal infection in a larger group of 25 MD patients. Irrespective of Lyme serological reactivity, all patients in our study group demonstrated histological evidence of epithelial spirochetal infection. Strength of evidence based on other testing varied among patients. Spirochetes identified as Borrelia strains by polymerase chain reaction (PCR) and/or in-situ DNA hybridization were detected in 24/25 of our study patients. Skin cultures containing Borrelia spirochetes were obtained from four patients, thus demonstrating that the organisms present in dermatological specimens were viable. Spirochetes identified by PCR as Borrelia burgdorferi were cultured from blood in seven patients and from vaginal secretions in three patients, demonstrating systemic infection. Based on these observations, a clinical classification system for MD is proposed. Our study using multiple detection methods confirms that MD is a true somatic illness associated with Borrelia spirochetes that cause Lyme disease. Further studies are needed to determine the optimal treatment for this spirochete-associated dermopathy.

  19. Effect of salivary gland extract from Ixodes ricinus ticks on the proliferation of Borrelia burgdorferi sensu stricto in vivo

    Czech Academy of Sciences Publication Activity Database

    Macháčková, Martina; Oborník, Miroslav; Kopecký, Jan

    2006-01-01

    Roč. 53, č. 2 (2006), s. 153-158 ISSN 0015-5683 R&D Projects: GA ČR GA524/05/0811 Grant - others:Studentská grantová agentura, Biologická fakulta Jihočeské univerzity(CZ) SGA2004/009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia burgdorferi * Ixodes ricinus * saliva-activated transmission Subject RIV: EC - Immunology Impact factor: 1.511, year: 2006

  20. Effect of forest clearing on the abundance of Ixodes ricinus ticks and the prevalence of Borrelia burgdorferi s.l

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Halouzka, Jiří; Juřicová, Zina; Šikutová, Silvie; Rudolf, Ivo

    2006-01-01

    Roč. 20, č. 2 (2006), s. 166-172 ISSN 0269-283X R&D Projects: GA ČR GA206/03/0726 EU Projects: European Commission(XE) 10284 - EDEN Institutional research plan: CEZ:AV0Z60930519 Keywords : Ixodes ricinus * Borrelia burgdorferi sensu lato * Lyme borreliosis risk Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 2.033, year: 2006

  1. Salivary gland extract from engorged Ixodes ricinus (Acari: Ixodidae) stimulates in vitro growth of Borrelia burgdorferi sensu lato

    Czech Academy of Sciences Publication Activity Database

    Rudolf, Ivo; Šikutová, Silvie; Kopecký, Jan; Hubálek, Zdeněk

    2010-01-01

    Roč. 50, č. 3 (2010), s. 294-298 ISSN 0233-111X R&D Projects: GA ČR GA206/03/0726; GA AV ČR IAA600960811 Institutional research plan: CEZ:AV0Z60930519; CEZ:AV0Z60220518 Keywords : salivary gland extract * Ixodes ricinus ticks * Borrelia burgdorferi sensu lato Subject RIV: EE - Microbiology, Virology Impact factor: 1.395, year: 2010

  2. In vitro susceptibility of Borrelia burgdorferi isolates to three antibiotics commonly used for treating equine Lyme disease.

    Science.gov (United States)

    Caol, Sanjie; Divers, Thomas; Crisman, Mark; Chang, Yung-Fu

    2017-09-29

    Lyme disease in humans is predominantly treated with tetracycline, macrolides or beta lactam antibiotics that have low minimum inhibitory concentrations (MIC) against Borrelia burgdorferi. Horses with Lyme disease may require long-term treatment making frequent intravenous or intramuscular treatment difficult and when administered orally those drugs may have either a high incidence of side effects or have poor bioavailability. The aim of the present study was to determine the in vitro susceptibility of three B. burgdorferi isolates to three antibiotics of different classes that are commonly used in practice for treating Borrelia infections in horses. Broth microdilution assays were used to determine minimum inhibitory concentration of three antibiotics (ceftiofur sodium, minocycline and metronidazole), for three Borrelia burgdorferi isolates. Barbour-Stoner-Kelly (BSK K + R) medium with a final inoculum of 10 6 Borrelia cells/mL and incubation periods of 72 h were used in the determination of MICs. Observed MICs indicated that all isolates had similar susceptibility to each drug but susceptibility to the tested antimicrobial agents varied; ceftiofur sodium (MIC = 0.08 μg/ml), minocycline hydrochloride (MIC = 0.8 μg/ml) and metronidazole (MIC = 50 μg/ml). The MIC against B. burgorferi varied among the three antibiotics with ceftiofur having the lowest MIC and metronidazole the highest MIC. The MIC values observed for ceftiofur in the study fall within the range of reported serum and tissue concentrations for the drug metabolite following ceftiofur sodium administration as crystalline-free acid. Minocycline and metronidazole treatments, as currently used in equine practice, could fall short of attaining MIC concentrations for B. burgdorferi.

  3. Europe-Wide Meta-Analysis of Borrelia burgdorferi Sensu Lato Prevalence in Questing Ixodes ricinus Ticks

    Czech Academy of Sciences Publication Activity Database

    Strnad, Martin; Hönig, Václav; Růžek, Daniel; Grubhoffer, Libor; Rego, Ryan O. M.

    2017-01-01

    Roč. 83, č. 15 (2017), č. článku e00609-17. ISSN 0099-2240 EU Projects: European Commission(XE) 278976 - ANTIGONE; European Commission(XE) 602272 - ANTIDotE Institutional support: RVO:60077344 Keywords : Borrelia burgdorferi sensu lato * tick * Ixodes ricinus * genospecies * meta-analysis * Lyme borreliosis * Lyme disease Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.807, year: 2016

  4. Prevalence of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) in Ixodes scapularis (Acari: Ixodidae) adults in New Jersey, 2000-2001.

    Science.gov (United States)

    Schulze, Terry L; Jordan, Robert A; Hung, Robert W; Puelle, Rose S; Markowski, Daniel; Chomsky, Martin S

    2003-07-01

    Using polymerase chain reaction, we analyzed 529 Ixodes scapularis Say adults collected from 16 of New Jersey's 21 counties for the presence of Borrelia burgdorferi, the etiological agent of Lyme disease. Overall, 261 (49.3%) were positive. B. burgdorferi was detected in ticks obtained from each county and from 53 of the 58 (93.1%) municipalities surveyed. The observed statewide prevalence in New Jersey is similar to those reported from other northeastern and mid-Atlantic states.

  5. Comparison of MKP and BSK-H media for the cultivation and isolation of Borrelia burgdorferi sensu lato.

    Directory of Open Access Journals (Sweden)

    Eva Ružić-Sabljić

    Full Text Available The isolation of B. burgdorferi sensu lato requires the use of complex cultivation media. The aim of the study was to compare the usefulness of BSK-H (a commercial medium produced by HiMedia, India and MKP medium. MKP and BSK-H media were prepared in accordance with the relevant protocols. Borrelia strains and skin culture biopsies were simultaneously inoculated into both media, incubated and checked for growth. Borrelial growth characteristics, isolation rates and characteristics of the isolated borreliae were analysed and compared. Initially, numbers of spirochaetes were higher in BSK-H than in MKP; however, in comparison with MKP, the strains subcultured in BSK-H medium were more frequently irregular, thin and non-motile, and rapidly died. In addition, the borrelial isolation rate from erythema migrans skin samples was higher in MKP than in BSK-H medium (108/171, 63.2% versus 70/171, 40.9%; p<0.0001. The far most frequently isolated species was Borrelia afzelii (92.9% and 97.2% strains isolated from BSK-H and MKP, respectively. Comparison of strains cultured from individual patients in both media showed differences in plasmid contents in 9/46 (19.6% strain pairs, and protein profiles differed in 30/43 (69.8% strain pairs, most often in the expression of OspC (in 27/28 patients OspC was expressed only in strains growing in MKP. BSK-H medium supports the growth of borrelial strains but MKP is superior with regard to the isolation rate, morphology and motility of strains. BSK-H medium supports fast initial growth of borreliae but this is followed by rapid deformation and death of the spirochaetes.

  6. Effect of tick saliva on signalling pathways activated by TLR-2 ligand and Borrelia afzelii in dendritic cells

    Czech Academy of Sciences Publication Activity Database

    Lieskovská, Jaroslava; Kopecký, Jan

    2012-01-01

    Roč. 35, č. 8-9 (2012), s. 421-429 ISSN 0141-9838 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GAP302/12/2208 Institutional support: RVO:60077344 Keywords : Borrelia * dendritic cells * tick saliva * Toll-like receptor signalling Subject RIV: EC - Immunology Impact factor: 2.208, year: 2012 http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3024.2012.01375.x/abstract

  7. Serological studies on the infection of dogs in Ontario with Borrelia burgdorferi, the etiological agent of Lyme disease

    OpenAIRE

    Artsob, Harvey; Barker, Ian K.; Fister, Richard; Sephton, Gregory; Dick, Daryl; Lynch, John A.; Key, Doug

    1993-01-01

    A serological study was undertaken to determine whether dogs in Ontario are being exposed to Borrelia burgdorferi, the etiological agent of Lyme disease. This study consisted of a survey of randomly selected dogs and testing of diagnostic submissions from candidate Lyme disease cases. The survey of 1,095 dogs, bled between January 1988 and August 1989, revealed a total of 65 (5.9%) enzyme-linked immunosorbent assay (ELISA) reactors, of which 22 had immuno-fluorescent antibody assay (IFA) tite...

  8. A plasmid-encoded nicotinamidase (PncA) is essential for infectivity of Borrelia burgdorferi in a mammalian host.

    Science.gov (United States)

    Purser, Joye E; Lawrenz, Matthew B; Caimano, Melissa J; Howell, Jerrilyn K; Radolf, Justin D; Norris, Steven J

    2003-05-01

    Borrelia burgdorferi, a spirochaete that causes Lyme borreliosis, contains 21 linear and circular plasmids thought to be important for survival in mammals or ticks. Our results demonstrate that the gene BBE22 encoding a nicotinamidase is capable of replacing the requirement for the 25 kb linear plasmid lp25 during mammalian infection. Transformation of B. burgdorferi lacking lp25 with a shuttle vector containing the lp25 gene BBE22 (pBBE22) restored infectivity in mice to a level comparable to that of wild-type Borrelia. This complementation also restored the growth and host adaptation of lp25-B. burgdorferi in dialysis membrane chambers (DMCs) implanted in rats. A single Cys to Ala conversion at the putative active site of BBE22 abrogated the ability of pBBE22 to re-establish infectivity or growth in DMCs. Additional Salmonella typhimurium complementation studies and enzymatic analysis demonstrated that the BBE22 gene product has nicotinamidase activity and is most probably required for the biosynthesis of NAD. These results indicate that some plasmid-encoded products fulfil physiological functions required in the enzootic cycle of pathogenic Borrelia.

  9. Spatial clustering of Borrelia burgdorferi sensu lato within populations of Allen's chipmunks and dusky-footed woodrats in northwestern California.

    Science.gov (United States)

    Hacker, Gregory M; Brown, Richard N; Fedorova, Natalia; Girard, Yvette A; Higley, Mark; Clueit, Bernadette; Lane, Robert S

    2018-01-01

    The ecology of Lyme borreliosis is complex in northwestern California, with several potential reservoir hosts, tick vectors, and genospecies of Borrelia burgdorferi sensu lato. The primary objective of this study was to determine the fine-scale spatial distribution of different genospecies in four rodent species, the California ground squirrel (Otospermophilus beecheyi), northern flying squirrel (Glaucomys sabrinus), dusky-footed woodrat (Neotoma fuscipes), and Allen's chipmunk (Neotamias senex). Rodents were live-trapped between June 2004 and May 2005 at the Hoopa Valley Tribal Reservation (HVTR) in Humboldt County, California. Ear-punch biopsies obtained from each rodent were tested by polymerase chain reaction (PCR) and sequencing analysis. The programs ArcGIS and SaTScan were used to examine the spatial distribution of genospecies. Multinomial log-linear models were used to model habitat and host-specific characteristics and their effect on the presence of each borrelial genospecies. The Akaike information criterion (AICc) was used to compare models and determine model fit. Borrelia burgdorferi sensu stricto was primarily associated with chipmunks and B. bissettiae largely with woodrats. The top model included the variables "host species", "month", and "elevation" (weight = 0.84). Spatial clustering of B. bissettiae was detected in the northwestern section of the HVTR, whereas B. burgdorferi sensu stricto was clustered in the southeastern section. We conclude that the spatial distribution of these borreliae are driven at least in part by host species, time-of-year, and elevation.

  10. Spheres of influence: Porphyromonas gingivalis outer membrane vesicles.

    Science.gov (United States)

    Gui, M J; Dashper, S G; Slakeski, N; Chen, Y-Y; Reynolds, E C

    2016-10-01

    Outer membrane vesicles (OMVs) are asymmetrical single bilayer membranous nanostructures produced by Gram-negative bacteria important for bacterial interaction with the environment. Porphyromonas gingivalis, a keystone pathogen associated with chronic periodontitis, produces OMVs that act as a virulence factor secretion system contributing to its pathogenicity. Despite their biological importance, the mechanisms of OMV biogenesis have not been fully elucidated. The ~14 times more curvature of the OMV membrane than cell outer membrane (OM) indicates that OMV biogenesis requires energy expenditure for significant curvature of the OMV membrane. In P. gingivalis, we propose that this may be achieved by upregulating the production of certain inner or outer leaflet lipids, which causes localized outward curvature of the OM. This results in selection of anionic lipopolysaccharide (A-LPS) and associated C-terminal domain (CTD) -family proteins on the outer surface due to their ability to accommodate the curvature. Deacylation of A-LPS may further enable increased curvature leading to OMV formation. Porphyromonas gingivalis OMVs that are selectively enriched in CTD-family proteins, largely the gingipains, can support bacterial coaggregation, promote biofilm development and act as an intercessor for the transport of non-motile bacteria by motile bacteria. The P. gingivalis OMVs are also believed to contribute to host interaction and colonization, evasion of immune defense mechanisms, and destruction of periodontal tissues. They may be crucial for both micro- and macronutrient capture, especially heme and probably other assimilable compounds for its own benefit and that of the wider biofilm community. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Detailed analysis of sequence changes occurring during vlsE antigenic variation in the mouse model of Borrelia burgdorferi infection.

    Directory of Open Access Journals (Sweden)

    Loïc Coutte

    2009-02-01

    Full Text Available Lyme disease Borrelia can infect humans and animals for months to years, despite the presence of an active host immune response. The vls antigenic variation system, which expresses the surface-exposed lipoprotein VlsE, plays a major role in B. burgdorferi immune evasion. Gene conversion between vls silent cassettes and the vlsE expression site occurs at high frequency during mammalian infection, resulting in sequence variation in the VlsE product. In this study, we examined vlsE sequence variation in B. burgdorferi B31 during mouse infection by analyzing 1,399 clones isolated from bladder, heart, joint, ear, and skin tissues of mice infected for 4 to 365 days. The median number of codon changes increased progressively in C3H/HeN mice from 4 to 28 days post infection, and no clones retained the parental vlsE sequence at 28 days. In contrast, the decrease in the number of clones with the parental vlsE sequence and the increase in the number of sequence changes occurred more gradually in severe combined immunodeficiency (SCID mice. Clones containing a stop codon were isolated, indicating that continuous expression of full-length VlsE is not required for survival in vivo; also, these clones continued to undergo vlsE recombination. Analysis of clones with apparent single recombination events indicated that recombinations into vlsE are nonselective with regard to the silent cassette utilized, as well as the length and location of the recombination event. Sequence changes as small as one base pair were common. Fifteen percent of recovered vlsE variants contained "template-independent" sequence changes, which clustered in the variable regions of vlsE. We hypothesize that the increased frequency and complexity of vlsE sequence changes observed in clones recovered from immunocompetent mice (as compared with SCID mice is due to rapid clearance of relatively invariant clones by variable region-specific anti-VlsE antibody responses.

  12. Central role of the Holliday junction helicase RuvAB in vlsE recombination and infectivity of Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Tao Lin

    2009-12-01

    Full Text Available Antigenic variation plays a vital role in the pathogenesis of many infectious bacteria and protozoa including Borrelia burgdorferi, the causative agent of Lyme disease. VlsE, a 35 kDa surface-exposed lipoprotein, undergoes antigenic variation during B. burgdorferi infection of mammalian hosts, and is believed to be a critical mechanism by which the spirochetes evade immune clearance. Random, segmental recombination between the expressed vlsE gene and adjacent vls silent cassettes generates a large number of different VlsE variants within the infected host. Although the occurrence and importance of vlsE sequence variation is well established, little is known about the biological mechanism of vlsE recombination. To identify factors important in antigenic variation and vlsE recombination, we screened transposon mutants of genes known to be involved in DNA recombination and repair for their effects on infectivity and vlsE recombination. Several mutants, including those in BB0023 (ruvA, BB0022 (ruvB, BB0797 (mutS, and BB0098 (mutS-II, showed reduced infectivity in immunocompetent C3H/HeN mice. Mutants in ruvA and ruvB exhibited greatly reduced rates of vlsE recombination in C3H/HeN mice, as determined by restriction fragment polymorphism (RFLP screening and DNA sequence analysis. In severe combined immunodeficiency (C3H/scid mice, the ruvA mutant retained full infectivity; however, all recovered clones retained the 'parental' vlsE sequence, consistent with low rates of vlsE recombination. These results suggest that the reduced infectivity of ruvA and ruvB mutants is the result of ineffective vlsE recombination and underscores the important role that vlsE recombination plays in immune evasion. Based on functional studies in other organisms, the RuvAB complex of B. burgdorferi may promote branch migration of Holliday junctions during vlsE recombination. Our findings are consistent with those in the accompanying article by Dresser et al., and together

  13. Outer planet probe cost estimates: First impressions

    Science.gov (United States)

    Niehoff, J.

    1974-01-01

    An examination was made of early estimates of outer planetary atmospheric probe cost by comparing the estimates with past planetary projects. Of particular interest is identification of project elements which are likely cost drivers for future probe missions. Data are divided into two parts: first, the description of a cost model developed by SAI for the Planetary Programs Office of NASA, and second, use of this model and its data base to evaluate estimates of probe costs. Several observations are offered in conclusion regarding the credibility of current estimates and specific areas of the outer planet probe concept most vulnerable to cost escalation.

  14. Prevalence of ticks and tick-borne pathogens: Babesia and Borrelia species in ticks infesting cats of Great Britain.

    Science.gov (United States)

    Davies, Saran; Abdullah, Swaid; Helps, Chris; Tasker, Séverine; Newbury, Hannah; Wall, Richard

    2017-09-15

    In a study of tick and tick-borne pathogen prevalence, between May and October 2016, 278 veterinary practices in Great Britain examined 1855 cats. Six-hundred and one cats were found to have attached ticks. The most frequently recorded tick species was Ixodes ricinus (57.1%), followed by Ixodes hexagonus (41.4%) and Ixodes trianguliceps (1.5%). Male cats, 4-6 years of age living in rural areas were most likely to be carrying a tick; hair length and tick treatment history had no significant association with attachment. For cats that were parasitized by ticks in large urban areas, I. hexagonus was the most frequent species recorded. Molecular analysis was possible for 541 individual tick samples, others were too damaged for analysis; Babesia spp., and Borrelia burgdorferi sensu lato were identified in 1.1% (n=6) and 1.8% (n=10) of these, respectively. Babesia spp. included Babesia vulpes sp. nov./Babesia microti-like (n=4) in I. hexagonus and Babesia venatorum (n=2) in I. ricinus. Borrelia burgdorferi s.l. species included Borrelia garinii (n=6) and Borrelia afzelii (n=4). The majority of B. burgorferi s.l. cases were found in I. ricinus, with B. afzelii in one I. hexagonus nymph. No Borrelia or Babesia spp. were present in I. trianguliceps. To determine a true prevalence for ticks on cats, practices that only submitted questionnaires from cats with ticks and practices that submitted fewer than 5 returns per week were removed; amongst those considered to have adhered strictly to the collection protocol, feline tick prevalence amongst cats that had access to the outdoors was 6.6%. These results show that ticks can be found on cats throughout Great Britain, which harbour a range of species of Babesia and B. burgdorferi s.l. and that cats, particularly in green spaces within urban areas, may form an important host for I. hexagonus, a known vector of pathogens. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. 27 CFR 9.207 - Outer Coastal Plain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Outer Coastal Plain. 9.207... Outer Coastal Plain. (a) Name. The name of the viticultural area described in this section is “Outer Coastal Plain”. For purposes of part 4 of this chapter, “Outer Coastal Plain” is a term of viticultural...

  16. Lack of IgG antibody seropositivity to Borrelia burgdorferi in patients with Parry-Romberg syndrome and linear morphea en coup de sabre in Mexico.

    Science.gov (United States)

    Gutiérrez-Gómez, Claudia; Godínez-Hana, Ana L; García-Hernández, Marisela; Suárez-Roa, María de Lourdes; Toussaint-Caire, Sonia; Vega-Memije, Elisa; Gutiérrez-Mendoza, Daniela; Pérez-Dosal, Marcia; Medina-De la Garza, Carlos E

    2014-08-01

    Progressive hemifacial atrophy or Parry-Romberg Syndrome (PRS) is a rare, acquired, progressive dysplasia of subcutaneous tissue and bone characterized by unilateral facial involvement. Its etiology is unknown, but theories about its pathogenesis include infectious, degenerative, autoimmune, and traumatic causes among others. The causal relationship of PRS and linear morphea en coup de sabre (LMCS) with Borrelia burgdorferi infection remains controversial. Our goal was to serologically determine anti-B. burgdorferi antibodies in patients diagnosed with PRS and LMCS to establish a possible association as a causative agent. We conducted a serology study with patients belonging to a group of 21 individuals diagnosed with PRS, six with LMCS, and 21 matched controls. Anti-Borrelia IgG antibodies were determined by ELISA. A descriptive statistical analysis and Fischer's exact test were done. In serological tests, only two cases had borderline values and were further analyzed by Western blot with non-confirmatory results. For both the PRS and LMCS group, the association test was not significant, suggesting a lack of association between PRS or LMCS and the presence of anti-Borrelia antibodies. In Mexico there are no previous studies on Borrelia infection and its relationship between PRS or LMCS. Our result showed a lack of association of either clinical entities with anti-Borrelia-antibodies. Former reports of this association may suggest coincidental findings without causal relationship. © 2014 The International Society of Dermatology.

  17. Validate or falsify: Lessons learned from a microscopy method claimed to be useful for detecting Borrelia and Babesia organisms in human blood.

    Science.gov (United States)

    Aase, Audun; Hajdusek, Ondrej; Øines, Øivind; Quarsten, Hanne; Wilhelmsson, Peter; Herstad, Tove K; Kjelland, Vivian; Sima, Radek; Jalovecka, Marie; Lindgren, Per-Eric; Aaberge, Ingeborg S

    2016-01-01

    A modified microscopy protocol (the LM-method) was used to demonstrate what was interpreted as Borrelia spirochetes and later also Babesia sp., in peripheral blood from patients. The method gained much publicity, but was not validated prior to publication, which became the purpose of this study using appropriate scientific methodology, including a control group. Blood from 21 patients previously interpreted as positive for Borrelia and/or Babesia infection by the LM-method and 41 healthy controls without known history of tick bite were collected, blinded and analysed for these pathogens by microscopy in two laboratories by the LM-method and conventional method, respectively, by PCR methods in five laboratories and by serology in one laboratory. Microscopy by the LM-method identified structures claimed to be Borrelia- and/or Babesia in 66% of the blood samples of the patient group and in 85% in the healthy control group. Microscopy by the conventional method for Babesia only did not identify Babesia in any samples. PCR analysis detected Borrelia DNA in one sample of the patient group and in eight samples of the control group; whereas Babesia DNA was not detected in any of the blood samples using molecular methods. The structures interpreted as Borrelia and Babesia by the LM-method could not be verified by PCR. The method was, thus, falsified. This study underlines the importance of doing proper test validation before new or modified assays are introduced.

  18. Outer-2-independent domination in graphs

    Indian Academy of Sciences (India)

    independent dominating set of a graph is a set of vertices of such that every vertex of ()\\ has a neighbor in and the maximum vertex degree of the subgraph induced by ()\\ is at most one. The outer-2-independent domination ...

  19. Intershell correlations in photoionization of outer shells

    Energy Technology Data Exchange (ETDEWEB)

    Amusia, M.Ya. [The Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); A.F. Ioffe Physical-Technical Institute, St. Petersburg 194021 (Russian Federation); Chernysheva, L.V. [A.F. Ioffe Physical-Technical Institute, St. Petersburg 194021 (Russian Federation); Drukarev, E.G. [National Research Center “Kurchatov Institute”, Konstantinov Petersburg Nuclear Physics Institute, St. Petersburg 188300 (Russian Federation)

    2016-02-15

    We demonstrate that the cross sections for photoionization of the outer shells are noticeably modified at the photon energies close to the thresholds of ionization of the inner shells due to correlations with the latter. The correlations may lead to increase or to decrease of the cross sections just above the ionization thresholds.

  20. Outer-2-independent domination in graphs

    Indian Academy of Sciences (India)

    Outer-2-independent domination in graphs. MARCIN KRZYWKOWSKI1,2,∗, DOOST ALI MOJDEH3 and MARYEM RAOOFI4. 1Department of Pure and Applied Mathematics, University of Johannesburg,. Johannesburg, South Africa. 2Faculty of Electronics, Telecommunications and Informatics, Gdansk University.

  1. Intershell correlations in photoionization of outer shells

    International Nuclear Information System (INIS)

    Amusia, M.Ya.; Chernysheva, L.V.; Drukarev, E.G.

    2016-01-01

    We demonstrate that the cross sections for photoionization of the outer shells are noticeably modified at the photon energies close to the thresholds of ionization of the inner shells due to correlations with the latter. The correlations may lead to increase or to decrease of the cross sections just above the ionization thresholds.

  2. Identification of new drug candidates against Borrelia burgdorferi using high-throughput screening

    Directory of Open Access Journals (Sweden)

    Pothineni VR

    2016-04-01

    Full Text Available Venkata Raveendra Pothineni,1 Dhananjay Wagh,1 Mustafeez Mujtaba Babar,1 Mohammed Inayathullah,1 David Solow-Cordero,2 Kwang-Min Kim,1 Aneesh V Samineni,1 Mansi B Parekh,1 Lobat Tayebi,3 Jayakumar Rajadas1 1Biomaterials and Advanced Drug Delivery Laboratory, Stanford Cardiovascular Pharmacology Division, Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, 2Chemical & Systems Biology, Stanford University School of Medicine, Stanford, CA, 3Department of Developmental Sciences, Marquette University School of Dentistry, Milwaukee, WI, USA Abstract: Lyme disease is the most common zoonotic bacterial disease in North America. It is estimated that >300,000 cases per annum are reported in USA alone. A total of 10%–20% of patients who have been treated with antibiotic therapy report the recrudescence of symptoms, such as muscle and joint pain, psychosocial and cognitive difficulties, and generalized fatigue. This condition is referred to as posttreatment Lyme disease syndrome. While there is no evidence for the presence of viable infectious organisms in individuals with posttreatment Lyme disease syndrome, some researchers found surviving Borrelia burgdorferi population in rodents and primates even after antibiotic treatment. Although such observations need more ratification, there is unmet need for developing the therapeutic agents that focus on removing the persisting bacterial form of B. burgdorferi in rodent and nonhuman primates. For this purpose, high-throughput screening was done using BacTiter-Glo assay for four compound libraries to identify candidates that stop the growth of B. burgdorferi in vitro. The four chemical libraries containing 4,366 compounds (80% Food and Drug Administration [FDA] approved that were screened are Library of Pharmacologically Active Compounds (LOPAC1280, the National Institutes of Health Clinical Collection, the Microsource Spectrum, and the Biomol FDA. We subsequently identified 150

  3. Outer Sphere Adsorption of Pb(II)EDTA on Goethite

    Energy Technology Data Exchange (ETDEWEB)

    Bargar, John R

    1999-07-16

    FTIR and EXAFS spectroscopic measurements were performed on Pb(II)EDTA adsorbed on goethite as functions of pH (4-6), Pb(II)EDTA concentration (0.11 {micro}M - 72 {micro}M), and ionic strength (16 {micro}M - 0.5M). FTIR measurements show no evidence for carboxylate-Fe(III) bonding or protonation of EDTA at Pb:EDTA = 1:1. Both FTIR and EXAFS measurements suggest that EDTA acts as a hexadentate ligand, with all four of its carboxylate and both amine groups bonded to Pb(II). No evidence was observed for inner-sphere Pb(II)-goethite bonding at Pb:EDTA = 1:1. Hence, the adsorbed complexes should have composition Pb(II)EDTA{sup 2{minus}}. Since substantial uptake of PbEDTA(II){sup 2{minus}} occurred in the samples, we infer that Pb(II)EDTA{sup 2{minus}} adsorbed as outer-sphere complexes and/or as complexes that lose part of their solvation shells and hydrogen bond directly to goethite surface sites. We propose the term ''hydration-sphere'' for the latter type of complexes because they should occupy space in the primary hydration spheres of goethite surface functional groups, and to distinguish this mode of sorption from common structural definitions of inner- and outer-sphere complexes. The similarity of Pb(II) uptake isotherms to those of other divalent metal ions complexed by EDTA suggests that they too adsorb by these mechanisms. The lack of evidence for inner-sphere EDTA-Fe(III) bonding suggests that previously proposed metal-ligand - promoted dissolution mechanisms should be modified, specifically to account for the presence of outer-sphere precursor species.

  4. Outer boundary as arrested history in general relativity

    International Nuclear Information System (INIS)

    Lau, Stephen R

    2002-01-01

    We present explicit outer boundary conditions for the canonical variables of general relativity. The conditions are associated with the causal evolution of a finite Cauchy domain, a so-called quasilocal boost, and they suggest a consistent scheme for modelling such an evolution numerically. The scheme involves a continuous boost in the spacetime orthogonal complement 'orthogonal' T p (B) of the tangent space T p (B) belonging to each point p on the system boundary B. We show how the boost rate may be computed numerically via equations similar to those appearing in canonical investigations of black-hole thermodynamics (although here holding at an outer two-surface rather than the bifurcate two-surface of a Killing horizon). We demonstrate the numerical scheme on a model example, the quasilocal boost of a spherical three-ball in Minkowski spacetime. Developing our general formalism with recent hyperbolic formulations of the Einstein equations in mind, we use Anderson and York's 'Einstein-Christoffel' hyperbolic system as the evolution equations for our numerical simulation of the model

  5. Outer boundary as arrested history in general relativity

    Science.gov (United States)

    Lau, Stephen R.

    2002-06-01

    We present explicit outer boundary conditions for the canonical variables of general relativity. The conditions are associated with the causal evolution of a finite Cauchy domain, a so-called quasilocal boost, and they suggest a consistent scheme for modelling such an evolution numerically. The scheme involves a continuous boost in the spacetime orthogonal complement ⊥Tp(B) of the tangent space Tp(B) belonging to each point p on the system boundary B. We show how the boost rate may be computed numerically via equations similar to those appearing in canonical investigations of black-hole thermodynamics (although here holding at an outer two-surface rather than the bifurcate two-surface of a Killing horizon). We demonstrate the numerical scheme on a model example, the quasilocal boost of a spherical three-ball in Minkowski spacetime. Developing our general formalism with recent hyperbolic formulations of the Einstein equations in mind, we use Anderson and York's 'Einstein-Christoffel' hyperbolic system as the evolution equations for our numerical simulation of the model.

  6. Outer boundary as arrested history in general relativity

    CERN Document Server

    Lau, S

    2002-01-01

    We present explicit outer boundary conditions for the canonical variables of general relativity. The conditions are associated with the causal evolution of a finite Cauchy domain, a so-called quasilocal boost, and they suggest a consistent scheme for modelling such an evolution numerically. The scheme involves a continuous boost in the spacetime orthogonal complement 'orthogonal' T sub p (B) of the tangent space T sub p (B) belonging to each point p on the system boundary B. We show how the boost rate may be computed numerically via equations similar to those appearing in canonical investigations of black-hole thermodynamics (although here holding at an outer two-surface rather than the bifurcate two-surface of a Killing horizon). We demonstrate the numerical scheme on a model example, the quasilocal boost of a spherical three-ball in Minkowski spacetime. Developing our general formalism with recent hyperbolic formulations of the Einstein equations in mind, we use Anderson and York's 'Einstein-Christoffel' hy...

  7. Outer- and middle-ear contributions to presbycusis in the Brown Norway rat.

    Science.gov (United States)

    Gratton, Michael Anne; Bateman, Kristin; Cannuscio, Joseph F; Saunders, James C

    2008-01-01

    This paper examines the contribution of the outer and middle ears to the hearing loss associated with presbycusis in Brown Norway rats. Animals were formed into two groups; young adults (2-3 months old) and aged animals (approximately 34 months old). Auditory brainstem response (ABR) thresholds were obtained with the outer ear intact or surgically removed. Tympanic membrane (TM) velocity transfer functions were measured from the umbo with the outer ear removed. The length of the auditory meatus, TM surface area, and TM thickness were quantified. The ABR thresholds were 17-26 dB less sensitive in the aged animals between 8.0 and 40.0 kHz when the outer ear was intact. A significant and reliable reduction in the aged rat velocity transfer function of 5-8 dB occurred between 10.0 and 32.0 kHz, while the low frequency velocity response was only a few decibels greater in the younger animals. The ABR threshold differences between young adult and aged ears were compensated by removing the outer/middle ear effects of aging to reveal a purely sensorineural component of presbycusis. The outer and middle ear effects were calculated directly when the ABR and TM velocity data were obtained with the outer ear removed. The outer ear intact condition was modeled in order to compare the ABR data obtained with the outer ear intact with the TM velocity data obtained with the outer removed. With either procedure, removal of the age-related contributions of the outer and middle ear to the ABR threshold resulted in similar age-related ABR threshold shifts between the two age groups. The pure sensorineural threshold shift component of the ABR response was restricted to frequencies between 5.0 and 20.0 kHz and reached a maximum of approximately 15 dB. These results support the conclusion that there is an outer- and middle-ear contribution to the threshold loss defining presbycusis. (c) 2008 S. Karger AG, Basel.

  8. Molecular characterization of the Borrelia burgdorferi in vivo-essential protein PncA.

    Science.gov (United States)

    Jewett, Mollie W; Jain, Sunny; Linowski, Angelika K; Sarkar, Amit; Rosa, Patricia A

    2011-10-01

    The conversion of nicotinamide to nicotinic acid by nicotinamidase enzymes is a critical step in maintaining NAD(+) homeostasis and contributes to numerous important biological processes in diverse organisms. In Borrelia burgdorferi, the nicotinamidase enzyme, PncA, is required for spirochaete survival throughout the infectious cycle. Mammals lack nicotinamidases and therefore PncA may serve as a therapeutic target for Lyme disease. Contrary to the in vivo importance of PncA, the current annotation for the pncA ORF suggests that the encoded protein may be inactive due to the absence of an N-terminal aspartic acid residue that is a conserved member of the catalytic triad of characterized PncA proteins. Herein, we have used genetic and biochemical strategies to determine the N-terminal sequence of B. burgdorferi PncA. Our data demonstrate that the PncA protein is 24 aa longer than the currently annotated sequence and that pncA translation is initiated from the rare, non-canonical initiation codon AUU. These findings are an important first step in understanding the catalytic function of this in vivo-essential protein.

  9. Serologic evidence for Borrelia hermsii infection in rodents on federally owned recreational areas in California.

    Science.gov (United States)

    Fritz, Curtis L; Payne, Jessica R; Schwan, Tom G

    2013-06-01

    Tick-borne relapsing fever (TBRF) is endemic in mountainous regions of the western United States. In California, the principal agent is the spirochete Borrelia hermsii, which is transmitted by the argasid tick Ornithodoros hermsi. Humans are at risk of TBRF when infected ticks leave an abandoned rodent nest in quest of a blood meal. Rodents are the primary vertebrate hosts for B. hermsii. Sciurid rodents were collected from 23 sites in California between August, 2006, and September, 2008, and tested for serum antibodies to B. hermsii by immunoblot using a whole-cell sonicate and a specific antigen, glycerophosphodiester phosphodiesterase (GlpQ). Antibodies were detected in 20% of rodents; seroprevalence was highest (36%) in chipmunks (Tamias spp). Seroprevalence in chipmunks was highest in the Sierra Nevada (41%) and Mono (43%) ecoregions and between 1900 and 2300 meters elevation (43%). The serological studies described here are effective in implicating the primary vertebrate hosts involved in the maintenance of the ticks and spirochetes in regions endemic for TBRF.

  10. Characterisation of silent and active genes for a variable large protein of Borrelia recurrentis

    Directory of Open Access Journals (Sweden)

    Scragg Ian G

    2002-10-01

    Full Text Available Abstract Background We report the characterisation of the variable large protein (vlp gene expressed by clinical isolate A1 of Borrelia recurrentis; the agent of the life-threatening disease louse-borne relapsing fever. Methods The major vlp protein of this isolate was characterised and a DNA probe created. Use of this together with standard molecular methods was used to determine the location of the vlp1B. recurrentis A1 gene in both this and other isolates. Results This isolate was found to carry silent and expressed copies of the vlp1B. recurrentis A1 gene on plasmids of 54 kbp and 24 kbp respectively, whereas a different isolate, A17, had only the silent vlp1B. recurrentis A17 on a 54 kbp plasmid. Silent and expressed vlp1 have identical mature protein coding regions but have different 5' regions, both containing different potential lipoprotein leader sequences. Only one form of vlp1 is transcribed in the A1 isolate of B. recurrentis, yet both 5' upstream sequences of this vlp1 gene possess features of bacterial promoters. Conclusion Taken together these results suggest that antigenic variation in B. recurrentis may result from recombination of variable large and small protein genes at the junction between lipoprotein leader sequence and mature protein coding region. However, this hypothetical model needs to be validated by further identification of expressed and silent variant protein genes in other B. recurrentis isolates.

  11. Seroprevalence of Borrelia burgdorferi antibodies in white-tailed deer from Texas

    Directory of Open Access Journals (Sweden)

    Shakirat A. Adetunji

    2016-08-01

    Full Text Available Lyme Disease is caused by the bacterial pathogen Borrelia burgdorferi, and is transmitted by the tick-vector Ixodes scapularis. It is the most prevalent arthropod-borne disease in the United States. To determine the seroprevalence of B. burgdorferi antibodies in white-tailed deer (Odocoileus virginianus from Texas, we analyzed serum samples (n = 1493 collected during the 2001–2015 hunting seasons, using indirect ELISA. Samples with higher sero-reactivity (0.803 and above than the negative control group (0.662 were further tested using a more specific standardized western immunoblot assay to rule out false positives. Using ELISA, 4.7% of the samples were sero-reactive against B. burgdorferi, and these originated in two eco-regions in Texas (Edwards Plateau and South Texas Plains. However, only 0.5% of the total samples were sero-reactive by standardized western immunoblot assay. Additionally, both ELISA and standardized western immunoblot assay results correlated with an increased incidence in human Lyme Disease cases reported in Texas. This is the first longitudinal study to demonstrate fluctuation in sero-reactivity of white-tailed deer to B. burgdorferi sensu stricto antigens in southern United States. Future ecological and geographical studies are needed to assess the environmental factors governing the prevalence of Lyme Disease in non-endemic areas of the southern United States.

  12. A case of canine borreliosis in Iran caused by Borrelia persica.

    Science.gov (United States)

    Shirani, Darush; Rakhshanpoor, Alaleh; Cutler, Sally Jane; Ghazinezhad, Behnaz; Naddaf, Saied Reza

    2016-04-01

    Tick-borne relapsing fever is an endemic disease in Iran, with most cases attributed to infection by Borrelia persica, which is transmitted by Ornithodoros tholozani soft ticks. Here, we report spirochetemia in blood of a puppy residing in Tehran, Iran. The causative species was identified by use of highly discriminative IGS sequencing; the 489 bp IGS sequence obtained in our study showed 99% identity (100% coverage) when compared with B. persica sequences derived from clinical cases or from O. tholozani ticks. Our IGS sequence also showed 99% similarity over 414 bp (85% coverage) with a strain from a domestic dog, and 96% over 328 bp (69% coverage) with a strain from a domestic cat. Pet-keeping in cosmopolitan cities like Tehran has become increasingly popular in recent years. Animals are often transported into the city in cages or cardboard boxes that might also harbor minute tick larvae and/or early stages of the nymphs bringing them into the urban environment. This may pose a threat to household members who buy and keep these puppies and as a result may come into close contact with infected ticks. Copyright © 2016 Elsevier GmbH. All rights reserved.

  13. Determination of Seroprevalence of Borrelia burgdorferi IgG in Adult Population Living in Trabzon.

    Science.gov (United States)

    Cora, Merve; Kaklıkkaya, Neşe; Topbaş, Murat; Çan, Gamze; Yavuzyılmaz, Asuman; Tosun, İlknur; Aydın, Faruk

    2017-01-01

    Lyme borreliosis is a tick-borne, multi-systemic infectious disease that is thought to be wide spread in Turkey even though studies on its seroprevalence are limited. To determine the seroprevalence of Lyme borreliosis in part of north-eastern Tur-key (in the city of Trabzon), and to identify possible relationships between seropositivity and various factors such as location, gender, age group, occupation, income, and educational level. Retrospective cross-sectional study. A total of 884 blood samples collected from provincial and district health centers serving a population of about 800,000 were included in this study. ELISA was used to determine the anti-Borrelia IgG antibody levels in the samples. Samples that yielded positive results by ELISA were further subjected to western blot (WB). IgG antibodies were found in 128 samples (14.5%). Statistical analysis revealed significant differences between age groups and educational levels in terms of the incidence of seropositivity, whereas location, gender, occupational group and income level had no effect (p<0.001, p<0.001, p=0.948, p=0.645, p=0.131, p=0.080 respectively). The risk of contracting Lyme borreliosis in Trabzon is high, and necessary measures need to be taken to avoid the spread of disease.

  14. Determination of Seroprevalence of Borrelia burgdorferi IgG in Adult Population Living in Trabzon

    Directory of Open Access Journals (Sweden)

    Merve Cora

    2017-02-01

    Full Text Available Background: Lyme borreliosis is a tick-borne, multi-systemic infectious disease that is thought to be wide spread in Turkey even though studies on its seroprevalence are limited. Aims: To determine the seroprevalence of Lyme borreliosis in part of north-eastern Tur-key (in the city of Trabzon, and to identify possible relationships between seropositivity and various factors such as location, gender, age group, occupation, income, and educational level. Study Design: Retrospective cross-sectional study. Methods: A total of 884 blood samples collected from provincial and district health centers serving a population of about 800,000 were included in this study. ELISA was used to determine the anti-Borrelia IgG antibody levels in the samples. Samples that yielded positive results by ELISA were further subjected to western blot (WB. Results: IgG antibodies were found in 128 samples (14.5%. Statistical analysis revealed significant differences between age groups and educational levels in terms of the incidence of seropositivity, whereas location, gender, occupational group and income level had no effect (p<0.001, p<0.001, p=0.948, p=0.645, p=0.131, p=0.080 respectively. Conclusions: The risk of contracting Lyme borreliosis in Trabzon is high, and necessary measures need to be taken to avoid the spread of disease

  15. Borrelia burgdorferi in ticks and dogs in the province of Vojvodina, Serbia*

    Directory of Open Access Journals (Sweden)

    Savić S.

    2010-12-01

    Full Text Available Lyme disease is a tick borne zoonotic infection, caused by Borrelia burgdorferi s.l. bacteria. For the transmission of the disease, the presence of ticks is a prerequisite. Lyme borreliosis mostly occurs in people and dogs, but it may occur in other animals. Ticks which carry B. burgdorferi s.l. in Serbia are of the Ixodes ricinus specis. In Serbia, Lyme disease was detected for the first time in the late ‘80-es. In dogs, clinical symptoms may occur even months after a tick bite, and include weakness, lymphadenopathy, fever, lameness, arthritis, etc. In our survey, we have observed tick and dog populations in the province of Vojvodina (northern part of Serbia. I. ricinus ticks were collected and examined for the presence of B. burgdorferi s.l. in several chosen locations. In addition, blood samples were collected from house dogs and pets from the same locations, and analyzed for the presence of antibodies specific for B. burgdorferi s.l. The results showed a mean infection of ticks of 22.12 %, and a mean seroprevalence of Lyme disease in dogs of 25.81 %. We conclude that in Vojvodina there is an actual risk of Lyme borreliosis for other animals and humans, because of the persistence of B. burgdorferi s.l. in both tick and dog populations.

  16. The cyclic-di-GMP signaling pathway in the Lyme disease spirochete, Borrelia burgdorferi

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Novak

    2014-05-01

    Full Text Available In nature, the Lyme disease spirochete Borrelia burgdorferi cycles between the unrelated environments of the Ixodes tick vector and mammalian host. In order to survive transmission between hosts, B. burgdorferi must be able to not only detect changes in its environment, but also rapidly and appropriately respond to these changes. One manner in which this obligate parasite regulates and adapts to its changing environment is through cyclic-di-GMP (c-di-GMP signaling. c-di-GMP has been shown to be instrumental in orchestrating the adaptation of B. burgdorferi to the tick environment. B. burgdorferi possesses only one set of c-di-GMP-metabolizing genes (one diguanylate cyclase and two distinct phosphodiesterases and one c-di-GMP-binding PilZ-domain protein designated as PlzA. While studies in the realm of c-di-GMP signaling in B. burgdorferi have exploded in the last few years, there are still many more questions than answers. Elucidation of the importance of c-di-GMP signaling to B. burgdorferi may lead to the identification of mechanisms that are critical for the survival of B. burgdorferi in the tick phase of the enzootic cycle as well as potentially delineate a role (if any c-di-GMP may play in the transmission and virulence of B. burgdorferi during the enzootic cycle, thereby enabling the development of effective drugs for the prevention and/or treatment of Lyme disease.

  17. Inefficient co-feeding transmission of Borrelia afzelii in two common European songbirds

    Science.gov (United States)

    Heylen, Dieter J. A.; Sprong, Hein; Krawczyk, Aleksandra; Van Houtte, Natalie; Genné, Dolores; Gomez-Chamorro, Andrea; van Oers, Kees; Voordouw, Maarten J.

    2017-01-01

    The spirochete bacterium Borrelia afzelii is the most common cause of Lyme borreliosis in Europe. This tick-borne pathogen can establish systemic infections in rodents but not in birds. However, several field studies have recovered larval Ixodes ricinus ticks infected with B. afzelii from songbirds suggesting successful transmission of B. afzelii. We reviewed the literature to determine which songbird species were the most frequent carriers of B. afzelii-infected I. ricinus larvae and nymphs. We tested experimentally whether B. afzelii is capable of co-feeding transmission on two common European bird species, the blackbird (Turdus merula) and the great tit (Parus major). For each bird species, four naïve individuals were infested with B. afzelii-infected I. ricinus nymphal ticks and pathogen-free larval ticks. None of the co-feeding larvae tested positive for B. afzelii in blackbirds, but a low percentage of infected larvae (3.33%) was observed in great tits. Transstadial transmission of B. afzelii DNA from the engorged nymphs to the adult ticks was observed in both bird species. However, BSK culture found that these spirochetes were not viable. Our study suggests that co-feeding transmission of B. afzelii is not efficient in these two songbird species. PMID:28054584

  18. Functional analysis of the Borrelia burgdorferi bba64 gene product in murine infection via tick infestation.

    Directory of Open Access Journals (Sweden)

    Toni G Patton

    Full Text Available Borrelia burgdorferi, the causative agent of Lyme borreliosis, is transmitted to humans from the bite of Ixodes spp. ticks. During the borrelial tick-to-mammal life cycle, B. burgdorferi must adapt to many environmental changes by regulating several genes, including bba64. Our laboratory recently demonstrated that the bba64 gene product is necessary for mouse infectivity when B. burgdorferi is transmitted by an infected tick bite, but not via needle inoculation. In this study we investigated the phenotypic properties of a bba64 mutant strain, including 1 replication during tick engorgement, 2 migration into the nymphal salivary glands, 3 host transmission, and 4 susceptibility to the MyD88-dependent innate immune response. Results revealed that the bba64 mutant's attenuated infectivity by tick bite was not due to a growth defect inside an actively feeding nymphal tick, or failure to invade the salivary glands. These findings suggested there was either a lack of spirochete transmission to the host dermis or increased susceptibility to the host's innate immune response. Further experiments showed the bba64 mutant was not culturable from mouse skin taken at the nymphal bite site and was unable to establish infection in MyD88-deficient mice via tick infestation. Collectively, the results of this study indicate that BBA64 functions at the salivary gland-to-host delivery interface of vector transmission and is not involved in resistance to MyD88-mediated innate immunity.

  19. The first case of imported Borrelia miyamotoi disease concurrent with Lyme disease.

    Science.gov (United States)

    Oda, Rentaro; Kutsuna, Satoshi; Sekikawa, Yoshiyuki; Hongo, Igen; Sato, Kozue; Ohnishi, Makoto; Kawabata, Hiroki

    2017-05-01

    Borrelia miyamotoi disease (BMD) is an emerging infectious disease caused by B. miyamotoi. Although BMD has been reported in the United States, Europe, and Japan, no case of imported BMD has been described in the world. Here, we report a 63-year-old American man living in Japan who presented with malaise, headache, myalgia, and arthralgia. We suspected Lyme disease because of his travel history to Minnesota and presence of erythema migrans. Serologic analysis supported our diagnosis, and doxycycline was administered for 14 days. However, we also suspected coinfection with BMD because of his fever, elevated liver function test results and his travel history. The patient was seropositive for the immunoglobulin M antibody to recombinant glycerophosphodiester phosphodiesterase, and was diagnosed with coinfection with BMD. This case suggests that BMD should be considered in febrile travelers returning from the Northeastern and Midwestern regions of the United States, and that BMD and Lyme disease coinfection should be considered to detect cases of imported BMD. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  20. Acute Zonal Cone Photoreceptor Outer Segment Loss.

    Science.gov (United States)

    Aleman, Tomas S; Sandhu, Harpal S; Serrano, Leona W; Traband, Anastasia; Lau, Marisa K; Adamus, Grazyna; Avery, Robert A

    2017-05-01

    The diagnostic path presented narrows down the cause of acute vision loss to the cone photoreceptor outer segment and will refocus the search for the cause of similar currently idiopathic conditions. To describe the structural and functional associations found in a patient with acute zonal occult photoreceptor loss. A case report of an adolescent boy with acute visual field loss despite a normal fundus examination performed at a university teaching hospital. Results of a complete ophthalmic examination, full-field flash electroretinography (ERG) and multifocal ERG, light-adapted achromatic and 2-color dark-adapted perimetry, and microperimetry. Imaging was performed with spectral-domain optical coherence tomography (SD-OCT), near-infrared (NIR) and short-wavelength (SW) fundus autofluorescence (FAF), and NIR reflectance (REF). The patient was evaluated within a week of the onset of a scotoma in the nasal field of his left eye. Visual acuity was 20/20 OU, and color vision was normal in both eyes. Results of the fundus examination and of SW-FAF and NIR-FAF imaging were normal in both eyes, whereas NIR-REF imaging showed a region of hyporeflectance temporal to the fovea that corresponded with a dense relative scotoma noted on light-adapted static perimetry in the left eye. Loss in the photoreceptor outer segment detected by SD-OCT co-localized with an area of dense cone dysfunction detected on light-adapted perimetry and multifocal ERG but with near-normal rod-mediated vision according to results of 2-color dark-adapted perimetry. Full-field flash ERG findings were normal in both eyes. The outer nuclear layer and inner retinal thicknesses were normal. Localized, isolated cone dysfunction may represent the earliest photoreceptor abnormality or a distinct entity within the acute zonal occult outer retinopathy complex. Acute zonal occult outer retinopathy should be considered in patients with acute vision loss and abnormalities on NIR-REF imaging, especially if

  1. Borrelia burgdorferi genospecies detection by RLB hybridization in Ixodes cinus ticks from different sites of North-Eastern Poland

    Directory of Open Access Journals (Sweden)

    Justyna Dunaj

    2014-06-01

    Full Text Available Introduction. RLB (Reverse Line Blot Hybridization is a molecular biology technique that might be used for [i]Borrelia burgdorferi [/i]sensu lato (sl DNA detection with genospecies specification. Among[i] B. burgdorferi[/i] sl genospecies at least 7 are regarded as pathogenic in Europe. objective. The aim of the study was to evaluate the frequency of different [i]Borrelia[/i] genospecies DNA detection in Ixodes ricinus ticks in the endemic area of North-Eastern Poland by using RLB. materials and method. Ixodes ricinus ticks were collected in May – June, from 6 different sites in North-Eastern Poland (Jakubin, Kolno, Grajewo, Suwałki, Siemiatycze, Białowieża by flagging. Extracted DNA was amplified by polymerase chain reaction (PCR targeting the intergenic spacer 5S 23S of [i]B. burgdorferi sl.[/i] PCR products were hybridised to 15 different oligonucleotide probes for 9 different [i]Borrelia [/i]genospecies ([i]B. burgdorferi sl, B. burgdorferi ss, B. garinii, B. afzelii, B. valaisiana, B. lusitaniae, B. spielmanii, B. bissettii and B. relapsing[/i] fever-like spirochetes (B. myamotoi by RLB. results. [i]Borrelia [/i]genospecies DNA was detected in 205 Ixodes ricinus ticks. Among 14 infected with [i]Borrelia[/i] ticks, 4 were identified as B. garinii and 10 as B. afzelii. Higher numbers of infected ticks were noticed in the eastern part of the research area, where large forest complexes dominate. Nymphs appeared to be the most frequently infected tick stage, which has an epidemiological meaning in the incidence of Lyme borreliosis. conclusions. The study demonstrated that RLB might be easily used in [i]Borrelia[/i] DNA detection with genospecies-identification, and indicated the domination of [i]B. afzelii and B. garinii [/i]in ticks from North-Eastern Poland.

  2. Performance of the LHCb Outer Tracker

    CERN Document Server

    Arink, R; Bachmann, S.; Bagaturia, Y.; Band, H.; Bauer, Th.; Berkien, A.; Farber, Ch.; Bien, A.; Blouw, J.; Ceelie, L.; Coco, V.; Deckenhoff, M.; Deng, Z.; Dettori, F.; van Eijk, D.; Ekelhof, R.; Gersabeck, E.; Grillo, L.; Hulsbergen, W.D.; Karbach, T.M.; Koopman, R.; Kozlinskiy, A.; Langenbruch, Ch.; Lavrentyev, V.; Linn, Ch.; Merk, M.; Merkel, J.; Meissner, M.; Michalowski, J.; Morawski, P.; Nawrot, A.; Nedos, M.; Pellegrino, A.; Polok, G.; van Petten, O.; Rovekamp, J.; Schimmel, F.; Schuylenburg, H.; Schwemmer, R.; Seyfert, P.; Serra, N.; Sluijk, T.; Spaan, B.; Spelt, J.; Storaci, B.; Szczekowski, M.; Swientek, S.; Tolk, S.; Tuning, N.; Uwer, U.; Wiedner, D.; Witek, M.; Zeng, M.; Zwart, A.

    2014-01-01

    The LHCb Outer Tracker is a gaseous detector covering an area of 5x6 m2 with 12 double layers of straw tubes. The detector with its services are described together with the commissioning and calibration procedures. Based on data of the first LHC running period from 2010 to 2012, the performance of the readout electronics and the single hit resolution and efficiency are presented. The efficiency to detect a hit in the central half of the straw is estimated to be 99.2%, and the position resolution is determined to be approximately 200 um. The Outer Tracker received a dose in the hottest region corresponding to 0.12 C/cm, and no signs of gain deterioration or other ageing effects are observed.

  3. The Outer Space as an Educational Motivation

    Science.gov (United States)

    Pérez-Pérez, Melquíades; Hernández-López, Montserrat

    2017-06-01

    STEAM is an educational approach to learning that uses Science, Technology, Engineering, the Arts and Mathematics as access points for guiding student inquiry, dialogue, and critical thinking. The end results are students who take thoughtful risks, engage in experiential learning, persist in problem-solving, embrace collaboration, and work through the creative process. The Outer Space is a window to the past and the future of our travel around the history of the Universe and can be used as a educational tool in primary and secondary education. This paper talks about the integration of the resources of European Space Agency, Space Awareness, Nuclio, Scientix and Schoolnet as motivation to integrate STEAM methodology in secondary education. Keywords: STEAM, outer space, motivation, methodology

  4. The Outer Banks of North Carolina

    Science.gov (United States)

    Dolan, Robert; Lins, Harry F.; Smith, Jodi Jones

    2016-12-27

    The Outer Banks of North Carolina are excellent examples of the nearly 300 barrier islands rimming the Atlantic and Gulf coasts of the United States. These low, sandy islands are among the most dynamic natural landscapes occupied by man. Beach sands move offshore, onshore, and along the shore in the direction of the prevailing longshore currents. In this way, sandy coasts continuously adjust to different tide, wave, and current conditions and to rising sea level that causes the islands to migrate landward.Despite such changes, barrier islands are of considerable environmental importance. The Outer Banks are home to diverse natural ecosystems that are adapted to the harsh coastal environment. Native species tend to be robust and many are specifically adapted to withstand salt spray, periodic saltwater flooding, and the islands’ well-drained sandy soil. The Outer Banks provide an important stopover for birds on the Atlantic flyway, and many species inhabit the islands year round. In addition, Outer Banks beaches provide an important nesting habitat for five endangered or threatened sea turtle species.European explorers discovered North Carolina’s barrier islands in the 16th century, although the islands were not permanently settled until the middle 17th century. By the early 19th century, shipbuilding and lumber industries were among the most successful, until forest resources were depleted. Commercial fishing eventually followed, and it expanded considerably after the Civil War. By the Great Depression, however, little industry existed on the Outer Banks. In response to the effects of a severe hurricane in 1933, the National Park Service and the Civilian Conservation Corps proposed a massive sand-fixation program to stabilize the moving sand and prevent storm waves from sweeping across the entire width of some sections of the islands. Between 1933 and 1940, this program constructed sand fencing on 185 kilometers (115 miles) of beach and planted grass seedlings

  5. Protection of nuclear facilities against outer aggressions

    International Nuclear Information System (INIS)

    Aussourd, P.; Candes, P.; Le Quinio, R.

    1976-01-01

    The various types of outer aggressions envisaged in safety analysis for nuclear facilities are reviewed. These outer aggressions are classified as natural and non-natural phenomena, the latter depending on the human activities in the vicinity of nuclear sites. The principal natural phenomena able to constitute aggressions are atmospheric phenomena (strong winds, snow storms, hail, frosting mists), hydrologie phenomena such as tides, surges, flood, low waters, and geologic phenomena such as earthquakes. Artificial phenomena are concerned with aircraft crashes, projectiles, fire, possible ruptures of dams, and intentional human aggressions. The protection against intentional human aggressions is of two sorts: first, the possibility of access to the installations mostly sensitive to sabotage are to be prevented or reduced, secondly redundant circuits and functions must be separated for preventing their simultaneous destruction in the case when sabotage actors have reach the core of the facility [fr

  6. Outer crust of nonaccreting cold neutron stars

    International Nuclear Information System (INIS)

    Ruester, Stefan B.; Hempel, Matthias; Schaffner-Bielich, Juergen

    2006-01-01

    The properties of the outer crust of nonaccreting cold neutron stars are studied by using modern nuclear data and theoretical mass tables, updating in particular the classic work of Baym, Pethick, and Sutherland. Experimental data from the atomic mass table from Audi, Wapstra, and Thibault of 2003 are used and a thorough comparison of many modern theoretical nuclear models, both relativistic and nonrelativistic, is performed for the first time. In addition, the influences of pairing and deformation are investigated. State-of-the-art theoretical nuclear mass tables are compared to check their differences concerning the neutron drip line, magic neutron numbers, the equation of state, and the sequence of neutron-rich nuclei up to the drip line in the outer crust of nonaccreting cold neutron stars

  7. Boundary layers of the earth's outer magnetosphere

    Science.gov (United States)

    Eastman, T. E.; Frank, L. A.

    1984-01-01

    The magnetospheric boundary layer and the plasma-sheet boundary layer are the primary boundary layers of the earth's outer magnetosphere. Recent satellite observations indicate that they provide for more than 50 percent of the plasma and energy transport in the outer magnetosphere although they constitute less than 5 percent by volume. Relative to the energy density in the source regions, plasma in the magnetospheric boundary layer is predominantly deenergized whereas plasma in the plasma-sheet boundary layer has been accelerated. The reconnection hypothesis continues to provide a useful framework for comparing data sampled in the highly dynamic magnetospheric environment. Observations of 'flux transfer events' and other detailed features near the boundaries have been recently interpreted in terms of nonsteady-state reconnection. Alternative hypotheses are also being investigated. More work needs to be done, both in theory and observation, to determine whether reconnection actually occurs in the magnetosphere and, if so, whether it is important for overall magnetospheric dynamics.

  8. Boundary layers of the earth's outer magnetosphere

    International Nuclear Information System (INIS)

    Eastman, T.E.; Frank, L.A.

    1984-01-01

    The magnetospheric boundary layer and the plasma-sheet boundary layer are the primary boundary layers of the earth's outer magnetosphere. Recent satellite observations indicate that they provide for more than 50 percent of the plasma and energy transport in the outer magnetosphere although they constitute less than 5 percent by volume. Relative to the energy density in the source regions, plasma in the magnetospheric boundary layer is predominantly deenergized whereas plasma in the plasma-sheet boundary layer has been accelerated. The reconnection hypothesis continues to provide a useful framework for comparing data sampled in the highly dynamic magnetospheric environment. Observations of flux transfer events and other detailed features near the boundaries have been recently interpreted in terms of nonsteady-state reconnection. Alternative hypotheses are also being investigated. More work needs to be done, both in theory and observation, to determine whether reconnection actually occurs in the magnetosphere and, if so, whether it is important for overall magnetospheric dynamics. 30 references

  9. Differential Rotation within the Earth's Outer Core

    Science.gov (United States)

    Hide, R.; Boggs, D. H.; Dickey, J. O.

    1998-01-01

    Non-steady differential rotation drive by bouyancy forces within the Earth's liquid outer core (OC) plays a key role not only in the generation of the main geomagnetic field by the magnetohydrodynamic (MHD) dynamo process but also in the excitation of irregular fluctuations in the angular speed of rotation of the overlying solid mantle, as evidenced by changes in the length of the day (LOD) on decadal and longer timescales (1-8).

  10. Fluxgate magnetometers for outer planets exploration

    Science.gov (United States)

    Acuna, M. H.

    1974-01-01

    The exploration of the interplanetary medium and the magnetospheres of the outer planets requires the implementation of magnetic field measuring instrumentation with wide dynamic range, high stability, and reliability. The fluxgate magnetometers developed for the Pioneer 11 and Mariner-Jupiter-Saturn missions are presented. These instruments cover the range of .01 nT to 2 million nT with optimum performance characteristics and low power consumption.

  11. Outer Limits of Biotechnologies: A Jewish Perspective

    Directory of Open Access Journals (Sweden)

    John D. Loike

    2018-01-01

    Full Text Available A great deal of biomedical research focuses on new biotechnologies such as gene editing, stem cell biology, and reproductive medicine, which have created a scientific revolution. While the potential medical benefits of this research may be far-reaching, ethical issues related to non-medical applications of these technologies are demanding. We analyze, from a Jewish legal perspective, some of the ethical conundrums that society faces in pushing the outer limits in researching these new biotechnologies.

  12. Borrelia burgdorferi genospecies detection by RLB hybridization in Ixodes cinus ticks from different sites of North-Eastern Poland

    OpenAIRE

    Justyna Dunaj; Joanna Maria Zajkowska; Maciej Kondrusik; Lise Gern; Oliver Rais; Anna Moniuszko; Sławomir Pancewicz; Renata Świerzbińska

    2014-01-01

    Introduction. RLB (Reverse Line Blot Hybridization) is a molecular biology technique that might be used for [i]Borrelia burgdorferi [/i]sensu lato (sl) DNA detection with genospecies specification. Among[i] B. burgdorferi[/i] sl genospecies at least 7 are regarded as pathogenic in Europe. objective. The aim of the study was to evaluate the frequency of different [i]Borrelia[/i] genospecies DNA detection in Ixodes ricinus ticks in the endemic area of North-Eastern Poland by using RLB. ...

  13. A New Strain Collection for Improved Expression of Outer Membrane Proteins

    Directory of Open Access Journals (Sweden)

    Ina Meuskens

    2017-11-01

    Full Text Available Almost all integral membrane proteins found in the outer membranes of Gram-negative bacteria belong to the transmembrane β-barrel family. These proteins are not only important for nutrient uptake and homeostasis, but are also involved in such processes as adhesion, protein secretion, biofilm formation, and virulence. As surface exposed molecules, outer membrane β-barrel proteins are also potential drug and vaccine targets. High production levels of heterologously expressed proteins are desirable for biochemical and especially structural studies, but over-expression and subsequent purification of membrane proteins, including outer membrane proteins, can be challenging. Here, we present a set of deletion mutants derived from E. coli BL21(DE3 designed for the over-expression of recombinant outer membrane proteins. These strains harbor deletions of four genes encoding abundant β-barrel proteins in the outer membrane (OmpA, OmpC, OmpF, and LamB, both single and in all combinations of double, triple, and quadruple knock-outs. The sequences encoding these outer membrane proteins were deleted completely, leaving only a minimal scar sequence, thus preventing the possibility of genetic reversion. Expression tests in the quadruple mutant strain with four test proteins, including a small outer membrane β-barrel protein and variants thereof as well as two virulence-related autotransporters, showed significantly improved expression and better quality of the produced proteins over the parent strain. Differences in growth behavior and aggregation in the presence of high salt were observed, but these phenomena did not negatively influence the expression in the quadruple mutant strain when handled as we recommend. The strains produced in this study can be used for outer membrane protein production and purification, but are also uniquely useful for labeling experiments for biophysical measurements in the native membrane environment.

  14. Distribution of Soft Ticks and Their Natural Infection with Borrelia in a Focus of Relapsing Fever in Iran

    Directory of Open Access Journals (Sweden)

    Z Aghighi

    2007-11-01

    Full Text Available Tick-borne diseases such as relapsing fever and Crimean-Congo Hemorrhagic Fever (CCHF are of public health impor¬tance in Iran. There are 471 reported cases of relapsing fever in 2003, according to the Ministry of Health of Iran.The num¬ber of cases has been increased in recent years. Its distribution is more or less prevalent in different parts of Iran. The aim of this study was to find out the fauna and natural infection of soft ticks with Borrelia in Qazvin Province, during their sea¬sonal activity. The province covers 15821 km² between 48-45 to 50-50 east of Greenwich Meridian of longitude and 35-37 to 36-45 north latitude of the equator. For this purpose a field study was carried out in the region. A total of 54 villages from 19 districts were selected ran¬domly and ticks were collected from their habitats according to the standard method. A total of 3197 Argasidae ticks were collected from human dwellings, poultry and animal shelters. They belonged to Argas and Or¬nithodoros genera which 36.8% were Argas persicus, 4% A. reflexus, 6.4% O. canestrini, 45.5% O. lahorensis and 7.3% O. tholozani. It should be noted that 12 ticks of O. erraticus were collected from 12 rodents borrows. We found that 8.82 % of O. tholozani ticks were infected with Borrelia persica and half of the O. erraticus were infected with Borrelia microti. All the people who are in¬volved with veterinary activities should be aware of disease transmission by the ticks. In the endemic area of the disease tick control is recommended.

  15. Seroprevalence of antibodies to Borrelia burgdorferi sensu lato in healthy adults from western Norway: risk factors and methodological aspects.

    Science.gov (United States)

    Hjetland, Reidar; Nilsen, Roy M; Grude, Nils; Ulvestad, Elling

    2014-11-01

    The aim of this study was to assess the seroprevalence of antibodies to Borrelia burgdorferi sensu lato in a healthy adult population from Sogn and Fjordane county in western Norway by different assays. Sera from 1213 blood donors at four different blood banks were analysed in Enzygnost Lyme link VlsE/IgG (IgG), Enzygnost Borreliosis IgM (IgM), and Immunetics C6 Lyme ELISA kit (C6). Sera showing positive or grey-zone reactivities were further examined with Borrelia-EUROLine-RN-AT IgG blot and Borrelia-EUROLine-RN-AT IgM blot. The seroprevalences were 9.6%, 8.2%, 8.4%, 6.4% and 5.7%, respectively. The seroprevalence for IgG was lower in the eastern part of the county and in owners of pet animals. It was higher in men, and increased with age and number of tick bites. C6 and IgG gave comparable results. IgM only was found in 4.5%, more often in women, did not increase with age, and showed no relationship with geography, and 56.4% were positive in IgM blot. In conclusion, antibodies to B. burgdorferi s.l. are common in blood donors in western Norway. The results may be used for evaluation of predictive values of test results in patients, as well as a basis for test algorithms in the laboratory. © 2014 APMIS. Published by John Wiley & Sons Ltd.

  16. Borrelia burgdorferi sensu lato spirochetes in wild birds in northwestern California: associations with ecological factors, bird behavior and tick infestation.

    Science.gov (United States)

    Newman, Erica A; Eisen, Lars; Eisen, Rebecca J; Fedorova, Natalia; Hasty, Jeomhee M; Vaughn, Charles; Lane, Robert S

    2015-01-01

    Although Borrelia burgdorferi sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult Ixodes pacificus ticks and potential reservoirs of the Lyme disease spirochete B. burgdorferi sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 I. pacificus larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by I. pacificus with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of Borrelia bissettii in birds. Moreover, our data suggest that the Golden-crowned Sparrow (Zonotrichia atricapilla), a non-resident species, could be an important reservoir for B. burgdorferi s.s. Of 12 individual birds (9 species) that carried B. burgdorferi s.l.-infected larvae, no birds carried the same genospecies of B. burgdorferi s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of B. burgdorferi s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and Borrelia infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States.

  17. Europe-Wide Meta-Analysis of Borrelia burgdorferi Sensu Lato Prevalence in Questing Ixodes ricinus Ticks.

    Science.gov (United States)

    Strnad, Martin; Hönig, Václav; Růžek, Daniel; Grubhoffer, Libor; Rego, Ryan O M

    2017-08-01

    Lyme borreliosis is the most common zoonotic disease transmitted by ticks in Europe and North America. Despite having multiple tick vectors, the causative agent, Borrelia burgdorferi sensu lato , is vectored mainly by Ixodes ricinus in Europe. In the present study, we aimed to review and summarize the existing data published from 2010 to 2016 concerning the prevalence of B. burgdorferi sensu lato spirochetes in questing I. ricinus ticks. The primary focus was to evaluate the infection rate of these bacteria in ticks, accounting for tick stage, adult tick gender, region, and detection method, as well as to investigate any changes in prevalence over time. The data obtained were compared to the findings of a previous metastudy. The literature search identified data from 23 countries, with 115,028 ticks, in total, inspected for infection with B. burgdorferi sensu lato We showed that the infection rate was significantly higher in adults than in nymphs and in females than in males. We found significant differences between European regions, with the highest infection rates in Central Europe. The most common genospecies were B. afzelii and B. garinii , despite a negative correlation of their prevalence rates. No statistically significant differences were found among the prevalence rates determined by conventional PCR, nested PCR, and real-time PCR. IMPORTANCE Borrelia burgdorferi sensu lato is a pathogenic bacterium whose clinical manifestations are associated with Lyme borreliosis. This vector-borne disease is a major public health concern in Europe and North America and may lead to severe arthritic, cardiovascular, and neurological complications if left untreated. Although pathogen prevalence is considered an important predictor of infection risk, solitary isolated data have only limited value. Here we provide summarized information about the prevalence of B. burgdorferi sensu lato spirochetes among host-seeking Ixodes ricinus ticks, the principal tick vector of

  18. Tick thioester-containing proteins and phagocytosis do not affect transmission of Borrelia afzelii from the competent vector ixodes ricinus

    Czech Academy of Sciences Publication Activity Database

    Urbanová, Veronika; Hajdušek, Ondřej; Hönig Mondeková, Helena; Šíma, Radek; Kopáček, Petr

    2017-01-01

    Roč. 7, MAR (2017), č. článku 73. ISSN 2235-2988 R&D Projects: GA ČR GJ15-12006Y; GA ČR GA13-11043S; GA ČR GA17-27386S; GA ČR GA17-27393S EU Projects: European Commission(XE) 602272 - ANTIDotE Institutional support: RVO:60077344 Keywords : Borrelia * complement * Ixodes * phagocytosis * thioester-containing proteins Subject RIV: EC - Immunology OBOR OECD: Immunology Impact factor: 4.300, year: 2016

  19. Molecular detection of Borrelia bissettii DNA in serum samples from patients in the Czech Republic with suspected borreliosis

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Růžek, Daniel; Piskunova, N.; Mallátová, N.; Grubhoffer, Libor

    2009-01-01

    Roč. 292, č. 2 (2009), s. 274-281 ISSN 0378-1097 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GD524/03/H133; GA ČR(CZ) GA524/06/1479 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia bissettii in human serum * causative agent * co-infection * co-detection of different species * phylogenetic analysis Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.199, year: 2009

  20. Predictive value of Borrelia burgdorferi IgG antibody levels in patients referred to a tertiary Lyme centre.

    Science.gov (United States)

    Zwerink, M; Zomer, T P; van Kooten, B; Blaauw, G; van Bemmel, T; van Hees, B C; Vermeeren, Y M; Landman, G W

    2018-03-01

    A two-step testing strategy is recommended in serological testing for Lyme borreliosis; positive and indeterminate enzyme-linked immunosorbent assay (ELISA) results are confirmed with immunoblots. Several ELISAs quantify the concentration of antibodies tested, however, no recommendation exists for an upper cut-off value at which an IgG ELISA is sufficient and the immunoblot can be omitted. The study objective was to determine at which IgG antibody level an immunoblot does not have any additional predictive value compared to ELISA results. Data of adult patients who visited a tertiary Lyme centre between 2008 and 2014 were analysed. Both an ELISA (Enzygnost Lyme link VlsE IgG) and immunoblot (recomLine blot Borrelia) were performed. Clinical data were extracted from the patient's digital medical record. Positive predictive values (PPVs) for either previous or active infection with Borrelia burgdorferi s.l. were calculated for different cut-off ELISA IgG antibody levels where the immunoblot was regarded as reference test. In total, 1454 patients were included. According to the two-step test strategy, 486 (33%), 69 (5%) and 899 (62%) patients had positive, indeterminate and negative Borrelia IgG serology, respectively. At IgG levels of 500 IU/ml and higher, all immunoblots were positive, resulting in a 100% PPV (95% CI: 97.0-100). At IgG levels of 200 IU/ml and higher, the PPV was 99.3% (95% CI: 97.4-99.8). In conclusion, at IgG levels of 200 IU/ml and higher, an ELISA was sufficient to detect antibodies to Borrelia burgdorferi s.l. At those IgG levels, a confirmatory immunoblot may be omitted in patients referred to a tertiary Lyme centre. Before these results can be implemented in routine diagnosis of Lyme borreliosis, confirmation of the results is necessary in other patient populations and using other quantitative ELISAs and immunoblots. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Culture and identification of Borrelia spirochetes in human vaginal and seminal secretions [version 3; referees: 2 approved, 2 not approved

    Directory of Open Access Journals (Sweden)

    Marianne J. Middelveen

    2015-04-01

    Full Text Available Background: Recent reports indicate that more than 300,000 cases of Lyme disease are diagnosed yearly in the USA. Preliminary clinical, epidemiological and immunological studies suggest that infection with the Lyme disease spirochete Borrelia burgdorferi (Bb could be transferred from person to person via intimate human contact without a tick vector. Failure to detect viable Borrelia spirochetes in vaginal and seminal secretions would argue against this hypothesis. Methods: Patients with and without a history of Lyme disease were selected for the study after informed consent was obtained. Serological testing for Bb was performed on all subjects. Semen or vaginal secretions were inoculated into BSK-H medium and cultured for four weeks. Examination of genital cultures and culture concentrates for the presence of spirochetes was performed using light and darkfield microscopy, and spirochete concentrates were subjected to Dieterle silver staining, anti-Bb immunohistochemical staining, molecular hybridization and PCR analysis for further characterization. Immunohistochemical and molecular testing was performed in three independent laboratories in a blinded fashion. Positive and negative controls were included in all experiments. Results: Control subjects who were asymptomatic and seronegative for Bb had no detectable spirochetes in genital secretions by PCR analysis. In contrast, spirochetes were observed in cultures of genital secretions from 11 of 13 subjects diagnosed with Lyme disease, and motile spirochetes were detected in genital culture concentrates from 12 of 13 Lyme disease patients using light and darkfield microscopy. Morphological features of spirochetes were confirmed by Dieterle silver staining and immunohistochemical staining of culture concentrates. Molecular hybridization and PCR testing confirmed that the spirochetes isolated from semen and vaginal secretions were strains of Borrelia, and all cultures were negative for treponemal

  2. 75 FR 1076 - Outer Continental Shelf Civil Penalties

    Science.gov (United States)

    2010-01-08

    ... initiate civil penalty proceedings; however, violations that cause injury, death, or environmental damage... DEPARTMENT OF THE INTERIOR Minerals Management Service Outer Continental Shelf Civil Penalties... daily civil penalty assessment. SUMMARY: The Outer Continental Shelf Lands Act requires the MMS to...

  3. Definition phase of Grand Tour missions/radio science investigations study for outer planets missions

    Science.gov (United States)

    Tyler, G. L.

    1972-01-01

    Scientific instrumentation for satellite communication and radio tracking systems in the outer planet exploration mission is discussed. Mission planning considers observations of planetary and satellite-masses, -atmospheres, -magnetic fields, -surfaces, -gravitational fields, solar wind composition, planetary radio emissions, and tests of general relativity in time delay and ray bending experiments.

  4. Intra-articular co-infection by Borrelia burgdorferi and Chlamydia trachomatis

    Science.gov (United States)

    Putschky, N; Schnarr, S; Wollenhaupt, J; Zeidler, H; Kuipers, J

    2001-01-01

    OBJECTIVE—Chlamydia trachomatis and Borrelia burgdorferi infections are frequently the cause of unexplained oligoarthritis, as shown by identification of bacteria specific DNA in joint material from patients with reactive arthritis, Lyme arthritis, and undifferentiated oligoarthritis. The aim of this study was to determine whether the two organisms occur simultaneously in joint material from patients with arthritis.
METHODS—Seventy six patients with unexplained arthritis were prospectively studied. Synovial fluid was obtained from all patients and examined for DNA from C trachomatis and B burgdorferi using specific polymerase chain reaction (PCR) protocols. Data concerning prior genitourinary infection or a history of tick bite were recorded and serum antibodies to C trachomatis and B burgdorferi were determined.
RESULTS—Six patients (8%) had DNA from both C trachomatis and B burgdorferi in the same synovial fluid specimen (mean leucocyte count 11.925/mm3, 65% granulocytes). These patients (four men, two women; mean age 33.7 years) all had oligoarthritis of the knee, ankle, or both (mean disease duration 11.3 months). From the history and serological examination, four patients had some evidence of actual or previous infection with one or other of the bacteria, while the other two patients had a positive serological test for Chlamydia only.
CONCLUSIONS—DNA from two different microorganisms which are known to be triggering agents for arthritis may be present simultaneously in joint material from patients with unexplained oligoarthritis. This finding raises the question as to whether, in such cases, one or both bacteria contribute to the pathogenesis of the disease or whether they are only innocent bystanders.

 PMID:11350854

  5. Resurgence of persisting non-cultivable Borrelia burgdorferi following antibiotic treatment in mice.

    Directory of Open Access Journals (Sweden)

    Emir Hodzic

    Full Text Available The agent of Lyme borreliosis, Borrelia burgdorferi, evades host immunity and establishes persistent infections in its varied mammalian hosts. This persistent biology may pose challenges to effective antibiotic treatment. Experimental studies in dogs, mice, and non-human primates have found persistence of B. burgdorferi DNA following treatment with a variety of antibiotics, but persisting spirochetes are non-cultivable. Persistence of B. burgdorferi DNA has been documented in humans following treatment, but the significance remains unknown. The present study utilized a ceftriaxone treatment regimen in the C3H mouse model that resulted in persistence of non-cultivable B. burgdorferi in order to determine their long-term fate, and to examine their effects on the host. Results confirmed previous studies, in which B. burgdorferi could not be cultured from tissues, but low copy numbers of B. burgdorferi flaB DNA were detectable in tissues at 2, 4 and 8 months after completion of treatment, and the rate of PCR-positive tissues appeared to progressively decline over time. However, there was resurgence of spirochete flaB DNA in multiple tissues at 12 months, with flaB DNA copy levels nearly equivalent to those found in saline-treated mice. Despite the continued non-cultivable state, RNA transcription of multiple B. burgdorferi genes was detected in host tissues, flaB DNA was acquired by xenodiagnostic ticks, and spirochetal forms could be visualized within ticks and mouse tissues by immunofluorescence and immunohistochemistry, respectively. A number of host cytokines were up- or down-regulated in tissues of both saline- and antibiotic-treated mice in the absence of histopathology, indicating host response to the presence of non-cultivable, despite the lack of inflammation in tissues.

  6. Antibody responses to Borrelia burgdorferi detected by western blot vary geographically in Canada.

    Science.gov (United States)

    Ogden, Nicholas H; Arsenault, Julie; Hatchette, Todd F; Mechai, Samir; Lindsay, L Robbin

    2017-01-01

    Lyme disease is emerging in eastern and central Canada, and most cases are diagnosed using the two-tier serological test (Enzyme Immuno Assay [EIA] followed by Western blot [WB]). Simplification of this algorithm would be advantageous unless it impacts test performance. In this study, accuracy of individual proteins of the IgG WB algorithm in predicting the overall test result in samples from Canadians was assessed. Because Borrelia burgdorferi strains vary geographically in Canada, geographic variations in serological responses were also explored. Metrics of relative sensitivity, specificity and the kappa statistic measure of concordance were used to assess the capacity of responses to individual proteins to predict the overall IgG WB result of 2524 EIA (C6)-positive samples from across Canada. Geographic and interannual variations in proportions of samples testing positive were explored by logistic regression. No one protein was highly concordant with the IgG WB result. Significant variations were found amongst years and geographic regions in the prevalence of samples testing positive using the overall IgG WB algorithm, and for individual proteins of the algorithm. In most cases the prevalence of samples testing positive were highest in Nova Scotia, and lower in samples from Manitoba westwards. These findings suggest that the current two tier test may not be simplified and continued use of the current two-tier test method and interpretation is recommended. Geographic and interannual variations in the prevalence of samples testing positive may be consistent with B. burgdorferi strain variation in Canada, and further studies are needed to explore this.

  7. Antibody responses to Borrelia burgdorferi detected by western blot vary geographically in Canada.

    Directory of Open Access Journals (Sweden)

    Nicholas H Ogden

    Full Text Available Lyme disease is emerging in eastern and central Canada, and most cases are diagnosed using the two-tier serological test (Enzyme Immuno Assay [EIA] followed by Western blot [WB]. Simplification of this algorithm would be advantageous unless it impacts test performance. In this study, accuracy of individual proteins of the IgG WB algorithm in predicting the overall test result in samples from Canadians was assessed. Because Borrelia burgdorferi strains vary geographically in Canada, geographic variations in serological responses were also explored. Metrics of relative sensitivity, specificity and the kappa statistic measure of concordance were used to assess the capacity of responses to individual proteins to predict the overall IgG WB result of 2524 EIA (C6-positive samples from across Canada. Geographic and interannual variations in proportions of samples testing positive were explored by logistic regression. No one protein was highly concordant with the IgG WB result. Significant variations were found amongst years and geographic regions in the prevalence of samples testing positive using the overall IgG WB algorithm, and for individual proteins of the algorithm. In most cases the prevalence of samples testing positive were highest in Nova Scotia, and lower in samples from Manitoba westwards. These findings suggest that the current two tier test may not be simplified and continued use of the current two-tier test method and interpretation is recommended. Geographic and interannual variations in the prevalence of samples testing positive may be consistent with B. burgdorferi strain variation in Canada, and further studies are needed to explore this.

  8. Borrelia burgdorferi requires glycerol for maximum fitness during the tick phase of the enzootic cycle.

    Directory of Open Access Journals (Sweden)

    Christopher J Pappas

    2011-07-01

    Full Text Available Borrelia burgdorferi, the spirochetal agent of Lyme disease, is a vector-borne pathogen that cycles between a mammalian host and tick vector. This complex life cycle requires that the spirochete modulate its gene expression program to facilitate growth and maintenance in these diverse milieus. B. burgdorferi contains an operon that is predicted to encode proteins that would mediate the uptake and conversion of glycerol to dihydroxyacetone phosphate. Previous studies indicated that expression of the operon is elevated at 23°C and is repressed in the presence of the alternative sigma factor RpoS, suggesting that glycerol utilization may play an important role during the tick phase. This possibility was further explored in the current study by expression analysis and mutagenesis of glpD, a gene predicted to encode glycerol 3-phosphate dehydrogenase. Transcript levels for glpD were significantly lower in mouse joints relative to their levels in ticks. Expression of GlpD protein was repressed in an RpoS-dependent manner during growth of spirochetes within dialysis membrane chambers implanted in rat peritoneal cavities. In medium supplemented with glycerol as the principal carbohydrate, wild-type B. burgdorferi grew to a significantly higher cell density than glpD mutant spirochetes during growth in vitro at 25°C. glpD mutant spirochetes were fully infectious in mice by either needle or tick inoculation. In contrast, glpD mutants grew to significantly lower densities than wild-type B. burgdorferi in nymphal ticks and displayed a replication defect in feeding nymphs. The findings suggest that B. burgdorferi undergoes a switch in carbohydrate utilization during the mammal to tick transition. Further, the results demonstrate that the ability to utilize glycerol as a carbohydrate source for glycolysis during the tick phase of the infectious cycle is critical for maximal B. burgdorferi fitness.

  9. Co-feeding transmission facilitates strain coexistence in Borrelia burgdorferi, the Lyme disease agent

    Directory of Open Access Journals (Sweden)

    S.L. States

    2017-06-01

    Full Text Available Coexistence of multiple tick-borne pathogens or strains is common in natural hosts and can be facilitated by resource partitioning of the host species, within-host localization, or by different transmission pathways. Most vector-borne pathogens are transmitted horizontally via systemic host infection, but transmission may occur in the absence of systemic infection between two vectors feeding in close proximity, enabling pathogens to minimize competition and escape the host immune response. In a laboratory study, we demonstrated that co-feeding transmission can occur for a rapidly-cleared strain of Borrelia burgdorferi, the Lyme disease agent, between two stages of the tick vector Ixodes scapularis while feeding on their dominant host, Peromyscus leucopus. In contrast, infections rapidly became systemic for the persistently infecting strain. In a field study, we assessed opportunities for co-feeding transmission by measuring co-occurrence of two tick stages on ears of small mammals over two years at multiple sites. Finally, in a modeling study, we assessed the importance of co-feeding on R0, the basic reproductive number. The model indicated that co-feeding increases the fitness of rapidly-cleared strains in regions with synchronous immature tick feeding. Our results are consistent with increased diversity of B. burgdorferi in areas of higher synchrony in immature feeding – such as the midwestern United States. A higher relative proportion of rapidly-cleared strains, which are less human pathogenic, would also explain lower Lyme disease incidence in this region. Finally, if co-feeding transmission also occurs on refractory hosts, it may facilitate the emergence and persistence of new pathogens with a more limited host range.

  10. Borrelia burgdorferi Sensu Lato in Siberian chipmunks (Tamias sibiricus) introduced in suburban forests in France.

    Science.gov (United States)

    Vourc'h, Gwenaël; Marmet, Julie; Chassagne, Michelle; Bord, Séverine; Chapuis, Jean-Louis

    2007-01-01

    Numerous vertebrate reservoirs have been described for Borrelia burgdorferi sensu lato (sl), which includes the etiological agents of Lyme Borreliosis (LB). The Siberian chipmunk (Tamias sibiricus) is a rodent originating from Asia, where it is suspected to be a B. burgdorferi reservoir. It has been intentionally released into the wild in Europe since the 1970s, but has not yet been subject to any study regarding its association with the LB agent. In this paper we studied Siberian chipmunk infestation with the LB vector (Ixodes ricinus) and infection prevalence by LB spirochetes in a suburban introduced population. We compared these findings with known competent reservoir hosts, the bank vole (Myodes [clethrionomys] glareolus) and wood mouse (Apodemus sylvaticus). All Siberian chipmunks were infested with larvae and larval abundance was higher in this species (mean number of larvae [95% Confidence Interval]: 73.5 [46.0, 117.2]) than in the two other rodent species (bank voles: 4.4 [3.0, 6.3] and wood mice: 10.2 [4.9, 21.2]). Significant factors affecting abundance of larvae were host species and sampling season. Nymphs were most prevalent on chipmunks (86.2%, mean: 5.1 [3.3, 8.0]), one vole carried only two nymphs, and none of the mice had any nymphs. Nymph abundance in chipmunks was affected by sampling season and sex. Furthermore, the infection prevalence of B. burgdorferi sl in the Siberian chipmunk was the highest (33.3%) and predominantly of B. afzelii. The infection prevalence was 14.1% in bank voles, but no wood mouse was found to be infected. Our results suggest that the Siberian chipmunk may be an important reservoir host for LB.

  11. Identification of Additional Anti-Persister Activity against Borrelia burgdorferi from an FDA Drug Library

    Directory of Open Access Journals (Sweden)

    Jie Feng

    2015-09-01

    Full Text Available Lyme disease is a leading vector-borne disease in the United States. Although the majority of Lyme patients can be cured with standard 2–4 week antibiotic treatment, 10%–20% of patients continue to suffer from prolonged post-treatment Lyme disease syndrome (PTLDS. While the cause for this is unclear, persisting organisms not killed by current Lyme antibiotics may be involved. In our previous study, we screened an FDA drug library and reported 27 top hits that showed high activity against Borrelia persisters. In this study, we present the results of an additional 113 active hits that have higher activity against the stationary phase B. burgdorferi than the currently used Lyme antibiotics. Many antimicrobial agents (antibiotics, antivirals, antifungals, anthelmintics or antiparasitics used for treating other infections were found to have better activity than the current Lyme antibiotics. These include antibacterials such as rifamycins (3-formal-rifamycin, rifaximin, rifamycin SV, thiostrepton, quinolone drugs (sarafloxacin, clinafloxacin, tosufloxacin, and cell wall inhibitors carbenicillin, tazobactam, aztreonam; antifungal agents such as fluconazole, mepartricin, bifonazole, climbazole, oxiconazole, nystatin; antiviral agents zanamivir, nevirapine, tilorone; antimalarial agents artemisinin, methylene blue, and quidaldine blue; antihelmintic and antiparasitic agents toltrazuril, tartar emetic, potassium antimonyl tartrate trihydrate, oxantel, closantel, hycanthone, pyrimethamine, and tetramisole. Interestingly, drugs used for treating other non-infectious conditions including verteporfin, oltipraz, pyroglutamic acid, pidolic acid, and dextrorphan tartrate, that act on the glutathione/γ-glutamyl pathway involved in protection against free radical damage, and also the antidepressant drug indatraline, were found to have high activity against stationary phase B. burgdorferi. Among the active hits, agents that affect cell membranes, energy

  12. Identification of Additional Anti-Persister Activity against Borrelia burgdorferi from an FDA Drug Library.

    Science.gov (United States)

    Feng, Jie; Weitner, Megan; Shi, Wanliang; Zhang, Shuo; Sullivan, David; Zhang, Ying

    2015-09-16

    Lyme disease is a leading vector-borne disease in the United States. Although the majority of Lyme patients can be cured with standard 2-4 week antibiotic treatment, 10%-20% of patients continue to suffer from prolonged post-treatment Lyme disease syndrome (PTLDS). While the cause for this is unclear, persisting organisms not killed by current Lyme antibiotics may be involved. In our previous study, we screened an FDA drug library and reported 27 top hits that showed high activity against Borrelia persisters. In this study, we present the results of an additional 113 active hits that have higher activity against the stationary phase B. burgdorferi than the currently used Lyme antibiotics. Many antimicrobial agents (antibiotics, antivirals, antifungals, anthelmintics or antiparasitics) used for treating other infections were found to have better activity than the current Lyme antibiotics. These include antibacterials such as rifamycins (3-formal-rifamycin, rifaximin, rifamycin SV), thiostrepton, quinolone drugs (sarafloxacin, clinafloxacin, tosufloxacin), and cell wall inhibitors carbenicillin, tazobactam, aztreonam; antifungal agents such as fluconazole, mepartricin, bifonazole, climbazole, oxiconazole, nystatin; antiviral agents zanamivir, nevirapine, tilorone; antimalarial agents artemisinin, methylene blue, and quidaldine blue; antihelmintic and antiparasitic agents toltrazuril, tartar emetic, potassium antimonyl tartrate trihydrate, oxantel, closantel, hycanthone, pyrimethamine, and tetramisole. Interestingly, drugs used for treating other non-infectious conditions including verteporfin, oltipraz, pyroglutamic acid, pidolic acid, and dextrorphan tartrate, that act on the glutathione/γ-glutamyl pathway involved in protection against free radical damage, and also the antidepressant drug indatraline, were found to have high activity against stationary phase B. burgdorferi. Among the active hits, agents that affect cell membranes, energy production, and reactive

  13. Isolation of Borrelia burgdorferi from the blood of seven patients with Lyme disease.

    Science.gov (United States)

    Nadelman, R B; Pavia, C S; Magnarelli, L A; Wormser, G P

    1990-01-01

    Borrelia burgdorferi, the etiologic agent of Lyme disease, has rarely been successfully cultured from blood. We report on seven patients from Westchester County, New York, with B. burgdorferi bacteremia diagnosed between April 1987 and August 1987. One hundred thirty-two attempts to isolate spirochetes were made on blood specimens obtained from 104 patients. Twenty-two of these specimens were obtained from nine patients who had recently been bitten by Ixodes ticks but who were asymptomatic. Heparinized blood or serum specimens (0.2 to 0.4 mL) were inoculated onto 6 mL of modified Barbour-Stoenner-Kelly medium. Lyme serology was performed by enzyme-linked immunosorbent polyvalent, IgM, and IgG assays, fluorescent immunoassay, and microhemagglutination. Four of the seven patients had erythema migrans, two had facial nerve palsy, and one had a flu-like syndrome without rash. These patients represented 21% (four of 19) of all patients with the characteristic skin lesion who had blood cultures for B. burgdorferi, and 40% (two of five) of all those with facial nerve palsy. Serologic testing was frequently nonreactive; two patients had no detectable antibody on multiple sera by five different assays. All patients improved with antibiotic treatment, and had negative subsequent blood cultures, but five of seven had persistent complaints after completion of therapy. Culturing blood for B. burgdorferi may be useful in confirming the diagnosis of Lyme disease in selected patients. Use of spirochete blood cultures may facilitate a better understanding of the pathogenesis and natural history of Lyme disease.

  14. Issues concerning outer space investments in international law ...

    African Journals Online (AJOL)

    Issues concerning outer space investments in international law. ... Recent improvements in technology have in essence increased the viability of outer space as the next frontier for international investment and development. In addition to ... Key words: Outer Space, Investments, International Law, International Space Station ...

  15. Dark matter in the outer solar system

    Science.gov (United States)

    Owen, T.; Cruikshank, D.; De Bergh, C.; Geballe, T.

    1994-01-01

    There are now a large number of small bodies in the outer solar system that are known to be covered with dark material. Attempts to identify that material have been thwarted by the absence of discrete absorption features in the reflection spectra of these planetesimals. An absorption at 2.2 micrometers that appeared to be present in several objects has not been confirmed by new observations. Three absorptions in the spectrum of the unusually red planetesimal 5145 Pholus are well-established, but their identity remains a mystery.

  16. Inner and Outer Life at Work

    DEFF Research Database (Denmark)

    Lundgaard Andersen, Linda

    2012-01-01

    involving people to people interactions offered by psychodynamic theories and methods take up a pivotal position. Psychoanalytic organisational and work life research explores how work, organisations and individuals are affected by psychic dynamics, the influence of the unconscious in the forms of human...... development and interaction situated in a societal context. Based on this substantial work I draw upon two influential psychoanalytical positions—the British Tavistock position and German psychoanalytic social psychology in order to situate and identify how to understand the inner and outer life at work...

  17. The urgency of outer territories anthropology

    Directory of Open Access Journals (Sweden)

    Miloš Milenković

    2016-02-01

    Full Text Available In the context of transforming a part of Serbian anthropology into social theoretic management of identity, I suggest both comparative historiographic and ethnographic learning from societies with similar post-colonial experience, with the aim to include the discipline into an urgent defense of Serbia and Belgrade from further ethno-profiteering interests of elites in/from outer territories, left over on the ruins of our ill judged, resource incompatible, exaggerated or immoral twentieth century adventures. Serbian anthropology, written by anthropologists to whom Serbia and Belgrade are "homeland" by origin or civilized choice, should play the key role in the defense of Serbian citizens from the interest of elites in/from the outer "homelands", particularly by revealing the processes for which it is, as a discipline, most expert at – the professionalization of ethnicity, interactive and hybrid nature of identity, instrumental nature of tradition and the identity politics in general. Having in mind the latest attempt, a particularly successful one, conducted by the end of the 20th and the beginning of the 21st century that the lives, health, well-being, dignity and future of persons born in and loyal to the interest of Serbia and Belgrade, in large scale, thoroughly and long term be sacrificed and dedicated to the interests of ethno-profiteering elites in/from outer territories, in this article I point to the possibility to, along with the comparative learning from the above mentioned post-colonial experiences, delicate experiences of urgent anthropology be applied as well as the rich tradition of collective research. This text analyzes the results of first such research, that represenst the initial, praiseworthy and a brave step in the wise striving to engage social sciences and humanities in a search of expert and not mythical/daily-political solutions of the key problem of the Serbian nation – that of how to settle the interests of the

  18. The Complement Binding and Inhibitory Protein CbiA of Borrelia miyamotoi Degrades Extracellular Matrix Components by Interacting with Plasmin(ogen

    Directory of Open Access Journals (Sweden)

    Ngoc T. T. Nguyen

    2018-02-01

    Full Text Available The emerging relapsing fever spirochete Borrelia (B. miyamotoi is transmitted by ixodid ticks and causes the so-called hard tick-borne relapsing fever or B. miyamotoi disease (BMD. More recently, we identified a surface-exposed molecule, CbiA exhibiting complement binding and inhibitory capacity and rendering spirochetes resistant to complement-mediated lysis. To gain deeper insight into the molecular principles of B. miyamotoi-host interaction, we examined CbiA as a plasmin(ogen receptor that enables B. miyamotoi to interact with the serine protease plasmin(ogen. Recombinant CbiA was able to bind plasminogen in a dose-dependent fashion. Moreover, lysine residues appear to play a crucial role in the protein-protein interaction as binding of plasminogen was inhibited by the lysine analog tranexamic acid as well as increasing ionic strength. Of relevance, plasminogen bound to CbiA can be converted by urokinase-type plasminogen activator (uPa to active plasmin which cleaved both, the chromogenic substrate S-2251 and its physiologic substrate fibrinogen. Concerning the involvement of specific amino acids in the interaction with plasminogen, lysine residues located at the C-terminus are frequently involved in the binding as reported for various other plasminogen-interacting proteins of Lyme disease spirochetes. Lysine residues located within the C-terminal domain were substituted with alanine to generate single, double, triple, and quadruple point mutants. However, binding of plasminogen to the mutated CbiA proteins was not affected, suggesting that lysine residues distant from the C-terminus might be involved in the interaction.

  19. Assessment of decorin-binding protein A to the infectivity of Borrelia burgdorferi in the murine models of needle and tick infection

    Directory of Open Access Journals (Sweden)

    Hagman Kayla E

    2008-05-01

    Full Text Available Abstract Background Decorin-binding proteins (Dbps A and B of Borrelia burgdorferi, the agent of Lyme disease, are surface-exposed lipoproteins that presumably bind to the extracellular matrix proteoglycan, decorin. B. burgdorferi infects various tissues including the bladder, heart, joints, skin and the central nervous system, and the ability of B. burgdorferi to bind decorin has been hypothesized to be important for this disseminatory pathogenic strategy. Results To determine the role of DbpBA in the infectious lifecycle of B. burgdorferi, we created a DbpBA-deficient mutant of B. burgdorferi strain 297 and compared the infectious phenotype of the mutant to the wild-type strain in the experimental murine model of Lyme borreliosis. The mutant strain exhibited a 4-log decrease in infectivity, relative to the wild-type strain, when needle inoculated into mice. Upon complementation of the DbpBA-mutant strain with DbpA, the wild-type level of infectivity was restored. In addition, we demonstrated that the DbpBA-deficient mutant was able to colonize Ixodes scapularis larval ticks after feeding on infected mice and persist within the ticks during the molt to the nymphal state. Moreover, surprisingly, the DbpBA-mutant strain was capable of being transmitted to naïve mice via tick bite, giving rise to infected mice. Conclusion These results suggest that DbpBA is not required for the natural tick-transmission process to mammals, despite inferences from needle-inoculation experiments implying a requirement for DbpBA during mammalian infection. The combined findings also send a cautionary note regarding how results from needle-inoculation experiments with mice should be interpreted.

  20. Potential alternative energy technologies on the Outer Continental Shelf.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.; Environmental Assessment

    2007-04-20

    This technical memorandum (TM) describes the technology requirements for three alternative energy technologies for which pilot and/or commercial projects on the U.S. Outer Continental Shelf (OCS) are likely to be proposed within the next five to seven years. For each of the alternative technologies--wind, wave, and ocean current--the TM first presents an overview. After each technology-specific overview, it describes the technology requirements for four development phases: site monitoring and testing, construction, operation, and decommissioning. For each phase, the report covers the following topics (where data are available): facility description, electricity generated, ocean area (surface and bottom) occupied, resource requirements, emissions and noise sources, hazardous materials stored or used, transportation requirements, and accident potential. Where appropriate, the TM distinguishes between pilot-scale (or demonstration-scale) facilities and commercial-scale facilities.

  1. Tick-borne relapsing fever imported from West Africa: diagnosis by quantitative buffy coat analysis and in vitro culture of Borrelia crocidurae

    NARCIS (Netherlands)

    van Dam, A. P.; van Gool, T.; Wetsteyn, J. C.; Dankert, J.

    1999-01-01

    West African tick-borne relapsing fever (TBRF) is difficult to diagnose due to the low number of spirochetes in the bloodstream of patients. Previously, the causative microorganism, Borrelia crocidurae, had never been cultured in vitro. TBRF was rapidly diagnosed for two patients returning from

  2. IrC2/Bf - A yeast and Borrelia responsive component of the complement system from the hard tick Ixodes ricinus

    Czech Academy of Sciences Publication Activity Database

    Urbanová, V.; Hajdušek, O.; Šíma, R.; Franta, Z.; Hönig Mondeková, Helena; Grunclová, L.; Bartošová-Sojková, P.; Jalovecká, M.; Kopáček, P.

    2018-01-01

    Roč. 76, FEB 2018 (2018), s. 86-94 ISSN 0145-305X Institutional support: RVO:61388971 Keywords : Borrelia * C3-complement convertase * Factor B Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.218, year: 2016

  3. Serological survey for antibodies to Borrelia burgdorferi in rodents and detection of spirochaetes in ticks and fleas in South Moravia (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Juřicová, Zina; Halouzka, Jiří; Hubálek, Zdeněk

    2002-01-01

    Roč. 57, č. 3 (2002), s. 383-387 ISSN 0006-3088 R&D Projects: GA AV ČR IAA6087601; GA ČR GA206/00/1204 Institutional research plan: CEZ:AV0Z6093917 Keywords : Borrelia burgdorferi * Lyme disease Subject RIV: EE - Microbiology, Virology Impact factor: 0.169, year: 2002

  4. Prevalence of Borrelia burgdorferi sensu lato genospecies in host-seeking Ixodes ricinus ticks in selected South Bohemian locations (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Danielová, V.; Daniel, M.; Rudenko, Natalia; Golovchenko, Maryna

    2004-01-01

    Roč. 12, č. 3 (2004), s. 151-156 ISSN 1210-7778 R&D Projects: GA ČR GA524/03/1326 Institutional research plan: CEZ:AV0Z6022909 Keywords : Ixodes ricinus * Borrelia * Czech Republic Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine

  5. Co-inoculation of Borrelia afzelii with tick salivary gland extract influences distribution of immunocompetent cells in the skin and lymph nodes of mice

    Czech Academy of Sciences Publication Activity Database

    Severinová, Jana; Salát, Jiří; Kročová, Z.; Řezníčková, Jana; Demová, Hana; Horká, Helena; Kopecký, Jan

    2005-01-01

    Roč. 50, č. 5 (2005), s. 457-463 ISSN 0015-5632 R&D Projects: GA ČR GA524/02/0901 Institutional research plan: CEZ:AV0Z6022909 Keywords : tick salivary gland extract * inflammation * Borrelia Subject RIV: EC - Immunology Impact factor: 0.918, year: 2005

  6. Polymorphisms at the innate immune receptor TLR2 are associated with Borrelia infection in a wild rodent population.

    Science.gov (United States)

    Tschirren, Barbara; Andersson, Martin; Scherman, Kristin; Westerdahl, Helena; Mittl, Peer R E; Råberg, Lars

    2013-05-22

    The discovery of the key role of Toll-like receptors (TLRs) in initiating innate immune responses and modulating adaptive immunity has revolutionized our understanding of vertebrate defence against pathogens. Yet, despite their central role in pathogen recognition and defence initiation, there is little information on how variation in TLRs influences disease susceptibility in natural populations. Here, we assessed the extent of naturally occurring polymorphisms at TLR2 in wild bank voles (Myodes glareolus) and tested for associations between TLR2 variants and infection with Borrelia afzelii, a common tick-transmitted pathogen in rodents and one of the causative agents of human Lyme disease. Bank voles in our population had 15 different TLR2 haplotypes (10 different haplotypes at the amino acid level), which grouped in three well-separated clusters. In a large-scale capture-mark-recapture study, we show that voles carrying TLR2 haplotypes of one particular cluster (TLR2c2) were almost three times less likely to be Borrelia infected than animals carrying other haplotypes. Moreover, neutrality tests suggested that TLR2 has been under positive selection. This is, to our knowledge, the first demonstration of an association between TLR polymorphism and parasitism in wildlife, and a striking example that genetic variation at innate immune receptors can have a large impact on host resistance.

  7. Isolation of live Borrelia burgdorferi sensu lato spirochaetes from patients with undefined disorders and symptoms not typical for Lyme borreliosis.

    Science.gov (United States)

    Rudenko, N; Golovchenko, M; Vancova, M; Clark, K; Grubhoffer, L; Oliver, J H

    2016-03-01

    Lyme borreliosis is a multisystem disorder with a diverse spectrum of clinical manifestations, caused by spirochaetes of the Borrelia burgdorferi sensu lato complex. It is an infectious disease that can be successfully cured by antibiotic therapy in the early stages; however, the possibility of the appearance of persistent signs and symptoms of disease following antibiotic treatment is recognized. It is known that Lyme borreliosis mimics multiple diseases that were never proven to have a spirochaete aetiology. Using complete modified Kelly-Pettenkofer medium we succeeded in cultivating live B. burgdorferi sensu lato spirochaetes from samples taken from people who suffered from undefined disorders, had symptoms not typical for Lyme borreliosis, but who had undergone antibiotic treatment due to a suspicion of having Lyme disease even though they were seronegative. We report the first recovery of live B. burgdorferi sensu stricto from residents of southeastern USA and the first successful cultivation of live Borrelia bissettii-like strain from residents of North America. Our results support the fact that B. bissettii is responsible for human Lyme borreliosis worldwide along with B. burgdorferi s.s. The involvement of new spirochaete species in Lyme borreliosis changes the understanding and recognition of clinical manifestations of this disease. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  8. Effectiveness of Stevia Rebaudiana Whole Leaf Extract Against the Various Morphological Forms of Borrelia Burgdorferi in Vitro

    Science.gov (United States)

    Theophilus, P. A. S.; Victoria, M. J.; Socarras, K. M.; Filush, K. R.; Gupta, K.; Luecke, D. F.; Sapi, E.

    2015-01-01

    Lyme disease is a tick-borne multisystemic disease caused by Borrelia burgdorferi. Administering antibiotics is the primary treatment for this disease; however, relapse often occurs when antibiotic treatment is discontinued. The reason for relapse remains unknown, but recent studies suggested the possibilities of the presence of antibiotic resistant Borrelia persister cells and biofilms. In this study, we evaluated the effectiveness of whole leaf Stevia extract against B. burgdorferi spirochetes, persisters, and biofilm forms in vitro. The susceptibility of the different forms was evaluated by various quantitative techniques in addition to different microscopy methods. The effectiveness of Stevia was compared to doxycycline, cefoperazone, daptomycin, and their combinations. Our results demonstrated that Stevia had significant effect in eliminating B. burgdorferi spirochetes and persisters. Subculture experiments with Stevia and antibiotics treated cells were established for 7 and 14 days yielding, no and 10% viable cells, respectively compared to the above-mentioned antibiotics and antibiotic combination. When Stevia and the three antibiotics were tested against attached biofilms, Stevia significantly reduced B. burgdorferi forms. Results from this study suggest that a natural product such as Stevia leaf extract could be considered as an effective agent against B. burgdorferi. PMID:26716015

  9. Direct Molecular Detection and Genotyping of Borrelia burgdorferi from Whole Blood of Patients with Early Lyme Disease

    Science.gov (United States)

    Eshoo, Mark W.; Crowder, Christopher C.; Rebman, Alison W.; Rounds, Megan A.; Matthews, Heather E.; Picuri, John M.; Soloski, Mark J.; Ecker, David J.; Schutzer, Steven E.; Aucott, John N.

    2012-01-01

    Direct molecular tests in blood for early Lyme disease can be insensitive due to low amount of circulating Borrelia burgdorferi DNA. To address this challenge, we have developed a sensitive strategy to both detect and genotype B. burgdorferi directly from whole blood collected during the initial patient visit. This strategy improved sensitivity by employing 1.25 mL of whole blood, a novel pre-enrichment of the entire specimen extract for Borrelia DNA prior to a multi-locus PCR and electrospray ionization mass spectrometry detection assay. We evaluated the assay on blood collected at the initial presentation from 21 endemic area patients who had both physician-diagnosed erythema migrans (EM) and positive two-tiered serology either at the initial visit or at a follow-up visit after three weeks of antibiotic therapy. Results of this DNA analysis showed detection of B. burgdorferi in 13 of 21 patients (62%). In most cases the new assay also provided the B. burgdorferi genotype. The combined results of our direct detection assay with initial physician visit serology resulted in the detection of early Lyme disease in 19 of 21 (90%) of patients at the initial visit. In 5 of 21 cases we demonstrate the ability to detect B. burgdorferi in early Lyme disease directly from whole blood specimens prior to seroconversion. PMID:22590620

  10. Serological studies on the infection of dogs in Ontario with Borrelia burgdorferi, the etiological agent of Lyme disease

    Science.gov (United States)

    Artsob, Harvey; Barker, Ian K.; Fister, Richard; Sephton, Gregory; Dick, Daryl; Lynch, John A.; Key, Doug

    1993-01-01

    A serological study was undertaken to determine whether dogs in Ontario are being exposed to Borrelia burgdorferi, the etiological agent of Lyme disease. This study consisted of a survey of randomly selected dogs and testing of diagnostic submissions from candidate Lyme disease cases. The survey of 1,095 dogs, bled between January 1988 and August 1989, revealed a total of 65 (5.9%) enzyme-linked immunosorbent assay (ELISA) reactors, of which 22 had immuno-fluorescent antibody assay (IFA) titers ≥1:32. All but one of the IFA-positive and 10 of the ELISA-positive, IFA-negative sera were further tested by western blot. Eight western blot positive and three equivocal reactors were obtained. Three of the eight confirmed reactors had visited areas known to be endemic for Lyme disease, leaving five reactors that might have been infected in previously undocumented areas for B. burgdorferi activity in Ontario. Diagnostic submissions of sera from 223 dogs were received between August 1987 and February 1992. Test results revealed 21 (9.4%) IFA reactors, of which only six had significant titers (≥1:256) and were reactive by an immunodot Borrelia test. All six dogs had travelled to known Lyme endemic areas. Based on results obtained from this study, it seems likely that the agent of Lyme disease is not widespread in Ontario. PMID:17424284

  11. Evaluation of BSK-H Complete Medium Supplemented with Rabbit Serum and Sodium Bicarbonate for the Growth of Borrelia anserina

    Directory of Open Access Journals (Sweden)

    Bilal Aslam, Iftikhar Hussain*, Muhammad Shahid Mahmood and Ahrar Khan1

    2013-04-01

    Full Text Available The present study was conducted to compare the effect of 3 formulations Barbour-Stoenner-Kelly (BSK medium on the growth of Borrelia (B. anserina, the causative agent of avian borreliosis. Three different formulations of BSK medium (BSK-H, BSK-II and BSK-H complete medium were prepared. For the isolation of B. anserina, Argas ticks were inoculated in all the three (BSK-H, BSK-II and BSK-H complete formulations of BSK medium. All the samples were also observed for the impact of BSK medium on the growth (Generation time, Growth per hour, Specific growth rate of B. anserina. Phase contrast microscopy was performed for the observation of viable B. anserina cells, and additional confirmation of all the isolates was done by performing indirect immunofluorescence assay and PCR. BSK-H complete medium supplemented with 6% rabbit serum and sodium bicarbonate was found best when compared to two other formulations of BSK medium with respect to the isolation, generation time and growth rate of Borrelia spirochetes.

  12. Magnetohydrodynamic Convection in the Outer Core and its Geodynamic Consequences

    Science.gov (United States)

    Kuang, Weijia; Chao, Benjamin F.; Fang, Ming

    2004-01-01

    The Earth's fluid outer core is in vigorous convection through much of the Earth's history. In addition to generating and maintaining Earth s time-varying magnetic field (geodynamo), the core convection also generates mass redistribution in the core and a dynamical pressure field on the core-mantle boundary (CMB). All these shall result in various core-mantle interactions, and contribute to surface geodynamic observables. For example, electromagnetic core-mantle coupling arises from finite electrically conducting lower mantle; gravitational interaction occurs between the cores and the heterogeneous mantle; mechanical coupling may also occur when the CMB topography is aspherical. Besides changing the mantle rotation via the coupling torques, the mass-redistribution in the core shall produce a spatial-temporal gravity anomaly. Numerical modeling of the core dynamical processes contributes in several geophysical disciplines. It helps explain the physical causes of surface geodynamic observables via space geodetic techniques and other means, e.g. Earth's rotation variation on decadal time scales, and secular time-variable gravity. Conversely, identification of the sources of the observables can provide additional insights on the dynamics of the fluid core, leading to better constraints on the physics in the numerical modeling. In the past few years, our core dynamics modeling efforts, with respect to our MoSST model, have made significant progress in understanding individual geophysical consequences. However, integrated studies are desirable, not only because of more mature numerical core dynamics models, but also because of inter-correlation among the geophysical phenomena, e.g. mass redistribution in the outer core produces not only time-variable gravity, but also gravitational core-mantle coupling and thus the Earth's rotation variation. They are expected to further facilitate multidisciplinary studies of core dynamics and interactions of the core with other

  13. Cosmics in the LHCb Outer Tracker

    CERN Document Server

    Aaij, Roel

    2010-01-01

    The LHCb experiment at the Large Hadron Collider studies the decay of B mesons to test the description of CP violation in the Standard Model and to search for new physics. The decay $B_s \\to \\mu^+ \\mu^-$ has been identified as very promising in the search for new physics. An excellent invariant mass resolution is required to suppress backgrounds to this decay. This in turn requires a momentum resolution of dp/p = 0.4%. The Outer Tracker is part of the LHCb tracking system and has been commissioned with cosmic muons. The noise in the Outer Tracker is shown to be less than 0.05%. To use drift time information in the reconstruction of cosmic tracks, the event time must be known. Four methods to obtain the event time are studied and compared. It is shown that the event time can be obtained with a resolution better than 2.6 ns. Using drift time information, tracks are reconstructed with a resolution of 344 $\\mu$m. Knowledge of the event time enables the calibration of electronic time offsets and the r(t)– relati...

  14. Gamma rays from pulsar outer gaps

    International Nuclear Information System (INIS)

    Chiang, J.; Romani, R.W.; Cheng Ho

    1993-01-01

    We describe a gamma ray pulsar code which computes the high energy photon emissivities from vacuum gaps in the outer magnetosphere, after the model outlined by Cheng, Ho and Ruderman (1986) and Ho (1989). Pair-production due to photon-photon interactions and radiation processes including curvature, synchrotron and inverse Compton processes are computed with an iterative scheme which converges to self-consistent photon and particle distributions for a sampling of locations in the outer magnetosphere. We follow the photons from these distributions as they propagate through the pulsar magnetosphere toward a distant observer. We include the effects of relativistic aberration, time-of-flight delays and reabsorption by photon-photon pair-production to determine an intensity map of the high energy pulsar emission on the sky. Using data from radio and optical observations to constrain the geometry of the magnetosphere as well as the possible observer viewing angles, we derive light curves and phase dependent spectra which can be directly compared to data from the Compton Observatory. Observations for Crab, Vela and the recently identified gamma ray pulsars Geminga, PSR1706-44 aNd PSR 1509-58 will provide important tests of our model calculations, help us to improve our picture of the relevant physics at work in pulsar magnetospheres and allow us to comment on the implications for future pulsar discoveries

  15. Residual Stress Testing of Outer 3013 Containers

    International Nuclear Information System (INIS)

    Dunn, K.

    2004-01-01

    A Gas Tungsten Arc Welded (GTAW) outer 3013 container and a laser welded outer 3013 container have been tested for residual stresses according to the American Society for Testing Materials (ASTM) Standard G-36-94 [1]. This ASTM standard describes a procedure for conducting stress-corrosion cracking tests in boiling magnesium chloride (MgCl2) solution. Container sections in both the as-fabricated condition as well as the closure welded condition were evaluated. Significantly large residual stresses were observed in the bottom half of the as-fabricated container, a result of the base to can fabrication weld because through wall cracks were observed perpendicular to the weld. This observation indicates that regardless of the closure weld technique, sufficient residual stresses exist in the as-fabricated container to provide the stress necessary for stress corrosion cracking of the container, at the base fabrication weld. Additionally, sufficiently high residual stresses were observed in both the lid and the body of the GTAW as well as the laser closure welded containers. The stresses are oriented perpendicular to the closure weld in both the container lid and the container body. Although the boiling MgCl2 test is not a quantitative test, a comparison of the test results from the closure welds shows that there are noticeably more through wall cracks in the laser closure welded container than in the GTAW closure welded container

  16. Radioiodination of an outer membrane protein in intact Rickettsia prowazekii

    International Nuclear Information System (INIS)

    Smith, D.K.; Winkler, H.H.

    1980-01-01

    Intact Rickettsia prowazekii was radiolabeled with the glucose oxidase-lactoperoxidase method of iodination. Separation of the rickettsial extract into cytoplasmic, outer and inner membrane fractions demonstrated that the outer membrane was preferentially labeled. Analysis of the polypeptides of these fractions on high-resolution slab polyacrylamide gels showed that most of the 125 I was in polypeptide T49, an outer membrane constituent. Additional outer membrane polypeptides were iodinated in broken envelope preparations, demonstrating that T49 is uniquely accessible to the external environment and the asymmetric polypeptide organization of the outer membrane

  17. Structure of Rotavirus Outer-Layer Protein VP7 Bound with a Neutralizing Fab

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Scott T.; Settembre, Ethan C.; Trask, Shane D.; Greenberg, Harry B.; Harrison, Stephen C.; Dormitzer, Philip R.; (Stanford-MED); (CH-Boston)

    2009-06-17

    Rotavirus outer-layer protein VP7 is a principal target of protective antibodies. Removal of free calcium ions (Ca{sup 2+}) dissociates VP7 trimers into monomers, releasing VP7 from the virion, and initiates penetration-inducing conformational changes in the other outer-layer protein, VP4. We report the crystal structure at 3.4 angstrom resolution of VP7 bound with the Fab fragment of a neutralizing monoclonal antibody. The Fab binds across the outer surface of the intersubunit contact, which contains two Ca{sup 2+} sites. Mutations that escape neutralization by other antibodies suggest that the same region bears the epitopes of most neutralizing antibodies. The monovalent Fab is sufficient to neutralize infectivity. We propose that neutralizing antibodies against VP7 act by stabilizing the trimer, thereby inhibiting the uncoating trigger for VP4 rearrangement. A disulfide-linked trimer is a potential subunit immunogen.

  18. T2 Magnetic Resonance Assay-Based Direct Detection of Three Lyme Disease-Related Borrelia Species in Whole-Blood Samples.

    Science.gov (United States)

    Snyder, Jessica L; Giese, Heidi; Bandoski-Gralinski, Cheryl; Townsend, Jessica; Jacobson, Beck E; Shivers, Robert; Schotthoefer, Anna M; Fritsche, Thomas R; Green, Clayton; Callister, Steven M; Branda, John A; Lowery, Thomas J

    2017-08-01

    In early Lyme disease (LD), serologic testing is insensitive and seroreactivity may reflect active or past infection. In this study, we evaluated a novel assay for the direct detection of three species of Borrelia spirochetes in whole blood. The T2 magnetic resonance (T2MR) assay platform was used to amplify Borrelia DNA released from intact spirochetes and to detect amplicon. Analytical sensitivity was determined from blood spiked with known concentrations of spirochetes, and the assay's limit of detection was found to be in the single-cell-per-milliliter range: 5 cells/ml for B. afzelii and 8 cells/ml for Borrelia burgdorferi and Borrelia garinii Clinical samples ( n = 66) from confirmed or suspected early LD patients were also analyzed. B. burgdorferi was detected using T2MR in 2/2 (100%) of blood samples from patients with confirmed early LD, based on the presence of erythema migrans and documentation of seroconversion or a positive real-time blood PCR. T2MR detected B. burgdorferi in blood samples from 17/54 (31%) of patients with probable LD, based on the presence of erythema migrans without documented seroconversion or of documented seroconversion in patients with a compatible clinical syndrome but without erythema migrans. Out of 21 clinical samples tested by real-time PCR, only 1 was positive and 13 were negative with agreement with T2MR. An additional 7 samples that were negative by real-time PCR were positive with T2MR. Therefore, T2MR enables a low limit of detection (LoD) for Borrelia spp. in whole blood samples and is able to detect B. burgdorferi in clinical samples. Copyright © 2017 American Society for Microbiology.

  19. Identification of host blood-meal sources and Borrelia in field-collected Ixodes ricinus ticks in north-western Poland

    Directory of Open Access Journals (Sweden)

    Beata Wodecka

    2015-12-01

    Full Text Available Forest animals play fundamental roles in the maintenance of [i]Ixodes ricinus[/i] and [i]Borrelia[/i] species in the forest biotope. To identify the forest vertebrate species that are host for I. ricinus and for the recognition of the reservoirs of [i]Borrelia[/i] species, the blood-meal of 325 [i]I. ricinus[/i] ticks collected at two forest sites in north-western Poland were analysed. Nested PCR was used to detect polymorphisms in a fragment of the mitochondrial 12S rRNA gene for the identification of the hosts species. The products were digested with the restriction enzymes, a combination that allows the identification of 60 vertebrate species, comprising 17 bird, 4 reptile and 39 mammalian species. Host DNA was detected in 244 (75%[i] I. ricinus[/i] individuals, with the species being detected and classified for 210 (86% samples. The restriction patterns resulted in the identification of 14 vertebrate species, including 2 species of birds, lizard, badger, rabbit, deer; most of the samples contained DNA from wild boar ([i]Sus scrofa[/i], red fox ([i]Vulpes vulpes[/i], red deer ([i]Cervus elaphus[/i] and roe deer ([i]Capreolus capreolus[/i]. Identification of Borrelia species was based on the flaB gene using nested PCR coupled to RFLP. This method allows the identification of all [i]Borrelia[/i] species transmitted by [i]I. ricinus [/i]in Europe, including [i]B. miyamotoi[/i] and 3 genetic variants of [i]B. garinii[/i]. In the studied isolates, 2 species belonging to [i]B. burgdorferi[/i] sensu lato were identified – B. [i]garinii [/i]and B. [i]afzelii[/i], and B. [i]miyamotoi,[/i] which are related to relapsing fever borreliae.

  20. Antibody profile to Borrelia burgdorferi in veterinarians from Nuevo León, Mexico, a non-endemic area of this zoonosis

    Directory of Open Access Journals (Sweden)

    Cassandra M. Skinner-Taylor

    2016-07-01

    Full Text Available Objectives: Lyme disease is a tick-borne disease caused by infections with Borrelia . Persons infected with Borrelia can be asymptomatic or can develop disseminated disease. Diagnosis and recognition of groups at risk of infection with Borrelia burgdorferi is of great interest to contemporary rheumatology. There are a few reports about Borrelia infection in Mexico, including lymphocytoma cases positive to B. burgdorferi sensu stricto by PCR and a patient with acrodermatitis chronica atrophicans. Veterinarians have an occupational risk due to high rates of tick contact. The aim of this work was to investigate antibodies to Borrelia in students at the Faculty of Veterinary Medicine and Zootechnics, at Nuevo León, Mexico, and determine the antibody profile to B. burgdorferi antigens. Material and methods: Sera were screened using a C6 ELISA, IgG and IgM ELISA using recombinant proteins from B. burgdorferi , B. gariniii and B. afzelii . Sera with positive or grey-zone values were tested by IgG Western blot to B. burgdorferi sensu stricto. Results : All volunteers reported tick exposures and 72.5% remembered tick bites. Only nine persons described mild Lyme disease related symptoms, including headaches, paresthesias, myalgias and arthralgias. None of the volunteers reported erythema migrans. Nine samples were confirmed by IgG Western blot. The profile showed 89% reactivity to OspA, 67% to p83, and 45% to BmpA. Conclusions : Positive sera samples shared antibody reactivity to the markers of late immune response p83 and BmpA, even if individuals did not present symptoms of Lyme arthritis or post-Lyme disease. The best criterion to diagnose Lyme disease in our country remains to be established, because it is probable that different strains coexist in Mexico. This is the first report of antibodies to B. burgdorferi in Latin American veterinarians. Veterinarians and high-risk people should be alert to take precautionary measures to prevent tick

  1. Outer membrane lipoprotein biogenesis: Lol is not the end.

    Science.gov (United States)

    Konovalova, Anna; Silhavy, Thomas J

    2015-10-05

    Bacterial lipoproteins are lipid-anchored proteins that contain acyl groups covalently attached to the N-terminal cysteine residue of the mature protein. Lipoproteins are synthesized in precursor form with an N-terminal signal sequence (SS) that targets translocation across the cytoplasmic or inner membrane (IM). Lipid modification and SS processing take place at the periplasmic face of the IM. Outer membrane (OM) lipoproteins take the localization of lipoproteins (Lol) export pathway, which ends with the insertion of the N-terminal lipid moiety into the inner leaflet of the OM. For many lipoproteins, the biogenesis pathway ends here. We provide examples of lipoproteins that adopt complex topologies in the OM that include transmembrane and surface-exposed domains. Biogenesis of such lipoproteins requires additional steps beyond the Lol pathway. In at least one case, lipoprotein sequences reach the cell surface by being threaded through the lumen of a beta-barrel protein in an assembly reaction that requires the heteropentomeric Bam complex. The inability to predict surface exposure reinforces the importance of experimental verification of lipoprotein topology and we will discuss some of the methods used to study OM protein topology. © 2015 The Author(s).

  2. The Outer Planets and their Moons Comparative Studies of the Outer Planets prior to the Exploration of the Saturn System by Cassini-Huygens

    CERN Document Server

    Encrenaz, T; Owen, T. C; Sotin, C

    2005-01-01

    This volume gives an integrated summary of the science related to the four giant planets in our solar system. It is the result of an ISSI workshop on «A comparative study of the outer planets before the exploration of Saturn by Cassini-Huygens» which was held at ISSI in Bern on January 12-16, 2004. Representatives of several scientific communities, such as planetary scientists, astronomers, space physicists, chemists and astrobiologists have met with the aim to review the knowledge on four major themes: (1) the study of the formation and evolution processes of the outer planets and their satellites, beginning with the formation of compounds and planetesimals in the solar nebula, and the subsequent evolution of the interiors of the outer planets, (2) a comparative study of the atmospheres of the outer planets and Titan, (3) the study of the planetary magnetospheres and their interactions with the solar wind, and (4) the formation and properties of satellites and rings, including their interiors, surfaces, an...

  3. Subdominant Outer Membrane Antigens in Anaplasma marginale: Conservation, Antigenicity, and Protective Capacity Using Recombinant Protein.

    Directory of Open Access Journals (Sweden)

    Deirdre R Ducken

    Full Text Available Anaplasma marginale is a tick-borne rickettsial pathogen of cattle with a worldwide distribution. Currently a safe and efficacious vaccine is unavailable. Outer membrane protein (OMP extracts or a defined surface protein complex reproducibly induce protective immunity. However, there are several knowledge gaps limiting progress in vaccine development. First, are these OMPs conserved among the diversity of A. marginale strains circulating in endemic regions? Second, are the most highly conserved outer membrane proteins in the immunogens recognized by immunized and protected animals? Lastly, can this subset of OMPs recognized by antibody from protected vaccinates and conserved among strains recapitulate the protection of outer membrane vaccines? To address the first goal, genes encoding OMPs AM202, AM368, AM854, AM936, AM1041, and AM1096, major subdominant components of the outer membrane, were cloned and sequenced from geographically diverse strains and isolates. AM202, AM936, AM854, and AM1096 share 99.9 to 100% amino acid identity. AM1041 has 97.1 to 100% and AM368 has 98.3 to 99.9% amino acid identity. While all four of the most highly conserved OMPs were recognized by IgG from animals immunized with outer membranes, linked surface protein complexes, or unlinked surface protein complexes and shown to be protected from challenge, the highest titers and consistent recognition among vaccinates were to AM854 and AM936. Consequently, animals were immunized with recombinant AM854 and AM936 and challenged. Recombinant vaccinates and purified outer membrane vaccinates had similar IgG and IgG2 responses to both proteins. However, the recombinant vaccinates developed higher bacteremia after challenge as compared to adjuvant-only controls and outer membrane vaccinates. These results provide the first evidence that vaccination with specific antigens may exacerbate disease. Progressing from the protective capacity of outer membrane formulations to

  4. Complex Population Structure of Lyme Borreliosis Group Spirochete Borrelia garinii in Subarctic Eurasia

    Science.gov (United States)

    Comstedt, Pär; Asokliene, Loreta; Eliasson, Ingvar; Olsen, Björn; Wallensten, Anders; Bunikis, Jonas; Bergström, Sven

    2009-01-01

    Borrelia garinii, a causative agent of Lyme borreliosis in Europe and Asia, is naturally maintained in marine and terrestrial enzootic cycles, which primarily involve birds, including seabirds and migratory passerines. These bird groups associate with, correspondingly, Ixodes uriae and Ixodes ricinus ticks, of which the latter species may bite and transmit the infection to humans. Studies of the overlap between these two natural cycles of B. garinii have been limited, in part due to the absence of representative collections of this spirochete's samples, as well as of the lack of reliable measure of the genetic heterogeneity of its strains. As a prerequisite for understanding the epidemiological correlates of the complex maintenance of B. garinii, the present study sought to assess the diversity and phylogenetic relationships of this species' strains from its natural hosts and patients with Lyme borreliosis from subarctic Eurasia. We used sequence typing of the partial rrs-rrl intergenic spacer (IGS) of archived and prospective samples of B. garinii from I. uriae ticks collected predominantly on Commander Islands in North Pacific, as well as on the islands in northern Sweden and arctic Norway. We also typed B. garinii samples from patients with Lyme borreliosis and I. ricinus ticks infesting migratory birds in southern Sweden, or found questing in selected sites on the islands in the Baltic Sea and Lithuania. Fifty-two (68%) of 77 B. garinii samples representing wide geographical range and associated with I. ricinus and infection of humans contributed 12 (60%) of total 20 identified IGS variants. In contrast, the remaining 25 (32%) samples recovered from I. uriae ticks from a few islands accounted for as many as 10 (50%) IGS types, suggesting greater local diversity of B. garinii maintained by seabirds and their ticks. Two IGS variants of the spirochete in common for both tick species were found in I. ricinus larvae from migratory birds, an indication that B

  5. Probable late lyme disease: a variant manifestation of untreated Borrelia burgdorferi infection

    Science.gov (United States)

    2012-01-01

    Background Lyme disease, a bacterial infection with the tick-borne spirochete Borrelia burgdorferi, can cause early and late manifestations. The category of probable Lyme disease was recently added to the CDC surveillance case definition to describe patients with serologic evidence of exposure and physician-diagnosed disease in the absence of objective signs. We present a retrospective case series of 13 untreated patients with persistent symptoms of greater than 12 weeks duration who meet these criteria and suggest a label of ‘probable late Lyme disease’ for this presentation. Methods The sample for this analysis draws from a retrospective chart review of consecutive, adult patients presenting between August 2002 and August 2007 to the author (JA), an infectious disease specialist. Patients were included in the analysis if their current illness had lasted greater than or equal to 12 weeks duration at the time of evaluation. Results Probable late Lyme patients with positive IgG serology but no history of previous physician-documented Lyme disease or appropriate Lyme treatment were found to represent 6% of our heterogeneous sample presenting with ≥ 12 weeks of symptom duration. Patients experienced a range of symptoms including fatigue, widespread pain, and cognitive complaints. Approximately one-third of this subset reported a patient-observed rash at illness onset, with a similar proportion having been exposed to non-recommended antibiotics or glucocorticosteroid treatment for their initial disease. A clinically significant response to antibiotics treatment was noted in the majority of patients with probable late Lyme disease, although post-treatment symptom recurrence was common. Conclusions We suggest that patients with probable late Lyme disease share features with both confirmed late Lyme disease and post-treatment Lyme disease syndrome. Physicians should consider the recent inclusion of probable Lyme disease in the CDC Lyme disease surveillance

  6. Recurrent Neural Network for Computing Outer Inverse.

    Science.gov (United States)

    Živković, Ivan S; Stanimirović, Predrag S; Wei, Yimin

    2016-05-01

    Two linear recurrent neural networks for generating outer inverses with prescribed range and null space are defined. Each of the proposed recurrent neural networks is based on the matrix-valued differential equation, a generalization of dynamic equations proposed earlier for the nonsingular matrix inversion, the Moore-Penrose inversion, as well as the Drazin inversion, under the condition of zero initial state. The application of the first approach is conditioned by the properties of the spectrum of a certain matrix; the second approach eliminates this drawback, though at the cost of increasing the number of matrix operations. The cases corresponding to the most common generalized inverses are defined. The conditions that ensure stability of the proposed neural network are presented. Illustrative examples present the results of numerical simulations.

  7. Ageing of the LHCb outer tracker

    CERN Document Server

    Blom, M R; Tuning, N

    2009-01-01

    The modules of the LHCb outer tracker have shown to suffer severe gain loss under moderate irradiation. This process is called ageing. Ageing of the modules results from contamination of the gas system by glue, araldite AY 103-1, used in their construction. In this thesis the ageing process will be shown. The schemes known to reduce, reverse, or prevent ageing have been investigated to determine their effect on the detector performance. The addition of O2 to the gas mixture lowers the detector response by an acceptable amount and does not affect the gas transport properties significantly. The ageing rate is decreased after extensive flushing and HV training could eventually repair the irradiation damage. The risks of HV training have been assessed. Furthermore, several gaseous and aquatic additions have been tested for their capability to prevent, or moderate ageing, but none showed significant improvement.

  8. The fate of the outer plasmasphere

    International Nuclear Information System (INIS)

    Elphic, R.C.; Thomsen, M.F.; Borovsky, J.E.

    1997-01-01

    Both the solar wind and the ionosphere contribute to Earth close-quote s magnetospheric plasma environment. However, it is not widely appreciated that the plasmasphere is a large reservoir of ionospheric ions that can be tapped to populate the plasma sheet. We employ empirical models of high-latitude ionospheric convection and the geomagnetic field to describe the transport of outer plasmasphere flux tubes from the dayside, over the polar cap and into the magnetotail during the early phases of a geomagnetic storm. We calculate that this process can give rise to high densities of cold plasma in the magnetotail lobes and in the near-Earth plasma sheet during times of enhanced geomagnetic activity, and especially during storms. This model can help explain both polar cap ionization patches and the presence of cold flowing ions downtail.copyright 1997 American Geophysical Union

  9. Impulsive ion acceleration in earth's outer magnetosphere

    International Nuclear Information System (INIS)

    Baker, D.N.; Belian, R.D.

    1985-01-01

    Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions are not of dominant importance for magnetotail plasma dynamics, they serve as an important tracer population. Their absolute intensity and brief temporal appearance bespeaks a strong and rapid acceleration process in the near-tail, very probably involving large induced electric fields substantially greater than those associated with cross-tail potential drops. Subsequent to their impulsive acceleration, these ions are injected into the outer trapping regions forming ion ''drift echo'' events, as well as streaming tailward away from their acceleration site in the near-earth plasma sheet. Most auroral ion acceleration processes occur (or are greatly enhanced) during the time that these global magnetospheric events are occurring in the magnetotail. A qualitative model relating energetic ion populations to near-tail magnetic reconnection at substorm onset followed by global redistribution is quite successful in explaining the primary observational features. Recent measurements of the elemental composition and charge-states have proven valuable for showing the source (solar wind or ionosphere) of the original plasma population from which the ions were accelerated

  10. Crystal structures of the Erp protein family members ErpP and ErpC from Borrelia burgdorferi reveal the reason for different affinities for complement regulator factor H.

    Science.gov (United States)

    Brangulis, Kalvis; Petrovskis, Ivars; Kazaks, Andris; Akopjana, Inara; Tars, Kaspars

    2015-05-01

    Borrelia burgdorferi is the causative agent of Lyme disease, which can be acquired after the bite of an infected Ixodes tick. As a strategy to resist the innate immunity and to successfully spread and proliferate, B. burgdorferi expresses a set of outer membrane proteins that are capable of binding complement regulator factor H (CFH), factor H-like protein 1 (CFHL-1) and factor H-related proteins (CFHR) to avoid complement-mediated killing. B. burgdorferi B31 contains three proteins that belong to the Erp (OspE/F-related) protein family and are capable of binding CFH and some CFHRs, namely ErpA, ErpC and ErpP. We have determined the crystal structure of ErpP at 2.53Å resolution and the crystal structure of ErpC at 2.15Å resolution. Recently, the crystal structure of the Erp family member OspE from B. burgdorferi N40 was determined in complex with CFH domains 19-20, revealing the residues involved in the complex formation. Despite the high sequence conservation between ErpA, ErpC, ErpP and the homologous protein OspE (78-80%), the affinity for CFH and CFHRs differs markedly among the Erp family members, suggesting that ErpC may bind only CFHRs but not CFH. A comparison of the binding site in OspE with those of ErpC and ErpP revealed that the extended loop region, which is only observed in the potential binding site of ErpC, plays an important role by preventing the binding of CFH. These results can explain the inability of ErpC to bind CFH, whereas ErpP and ErpA still possess the ability to bind CFH. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Stem loop sequences specific to transposable element IS605 are found linked to lipoprotein genes in Borrelia plasmids.

    Directory of Open Access Journals (Sweden)

    Nicholas Delihas

    Full Text Available BACKGROUND: Plasmids of Borrelia species are dynamic structures that contain a large number of repetitive genes, gene fragments, and gene fusions. In addition, the transposable element IS605/200 family, as well as degenerate forms of this IS element, are prevalent. In Helicobacter pylori, flanking regions of the IS605 transposase gene contain sequences that fold into identical small stem loops. These function in transposition at the single-stranded DNA level. METHODOLOGY/PRINCIPAL FINDINGS: In work reported here, bioinformatics techniques were used to scan Borrelia plasmid genomes for IS605 transposable element specific stem loop sequences. Two variant stem loop motifs are found in the left and right flanking regions of the transposase gene. Both motifs appear to have dispersed in plasmid genomes and are found "free-standing" and phylogenetically conserved without the associated IS605 transposase gene or the adjacent flanking sequence. Importantly, IS605 specific stem loop sequences are also found at the 3' ends of lipoprotein genes (PFam12 and PFam60, however the left and right sequences appear to develop their own evolutionary patterns. The lipoprotein gene-linked left stem loop sequences maintain the IS605 stem loop motif in orthologs but only at the RNA level. These show mutations whereby variants fold into phylogenetically conserved RNA-type stem loops that contain the wobble non-Watson-Crick G-U base-pairing. The right flanking sequence is associated with the family lipoprotein-1 genes. A comparison of homologs shows that the IS605 stem loop motif rapidly dissipates, but a more elaborate secondary structure appears to develop in its place. CONCLUSIONS/SIGNIFICANCE: Stem loop sequences specific to the transposable element IS605 are present in plasmid regions devoid of a transposase gene and significantly, are found linked to lipoprotein genes in Borrelia plasmids. These sequences are evolutionarily conserved and/or structurally developed in

  12. The Presence of Borrelia miyamotoi, A Relapsing Fever Spirochaete, in Questing Ixodes ricinus in Belgium and in The Netherlands.

    Science.gov (United States)

    Cochez, C; Heyman, P; Heylen, D; Fonville, M; Hengeveld, P; Takken, W; Simons, L; Sprong, H

    2015-08-01

    Borrelia miyamotoi is a tick-borne bacterium that may cause relapsing fever in humans. As this pathogen has been discovered in Europe only recently, only little is known about its local impact on human health and its spatial distribution. In this study, we show the results of PCR screenings for B. miyamotoi in flagged Ixodes ricinus from Belgium and the Netherlands. B. miyamotoi was detected in nine of thirteen, and three of five locations from the Netherlands and Belgium, respectively. These outcomes indicate that B. miyamotoi is more spread than previously thought. The mean infection rate B. miyamotoi was 1.14% for Belgium and 3.84% for the Netherlands. © 2014 Blackwell Verlag GmbH.

  13. HERSCHEL OBSERVATIONS OF THE T CHA TRANSITION DISK: CONSTRAINING THE OUTER DISK PROPERTIES

    International Nuclear Information System (INIS)

    Cieza, Lucas A.; Olofsson, Johan; Henning, Thomas; Harvey, Paul M.; Evans II, Neal J.; Pinte, Christophe; Augereau, Jean-Charles; Ménard, Francois; Merín, Bruno; Najita, Joan

    2011-01-01

    T Cha is a nearby (d ∼ 100 pc) transition disk known to have an optically thin gap separating optically thick inner and outer disk components. Huélamo et al. recently reported the presence of a low-mass object candidate within the gap of the T Cha disk, giving credence to the suspected planetary origin of this gap. Here we present the Herschel photometry (70, 160, 250, 350, and 500 μm) of T Cha from the 'Dust, Ice, and Gas in Time' Key Program, which bridges the wavelength range between existing Spitzer and millimeter data and provide important constraints on the outer disk properties of this extraordinary system. We model the entire optical to millimeter wavelength spectral energy distribution (SED) of T Cha (19 data points between 0.36 and 3300 μm without any major gaps in wavelength coverage). T Cha shows a steep spectral slope in the far-IR, which we find clearly favors models with outer disks containing little or no dust beyond ∼40 AU. The full SED can be modeled equally well with either an outer disk that is very compact (only a few AU wide) or a much larger one that has a very steep surface density profile. That is, T Cha's outer disk seems to be either very small or very tenuous. Both scenarios suggest a highly unusual outer disk and have important but different implications for the nature of T Cha. Spatially resolved images are needed to distinguish between the two scenarios.

  14. HERSCHEL OBSERVATIONS OF THE T CHA TRANSITION DISK: CONSTRAINING THE OUTER DISK PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Cieza, Lucas A. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Olofsson, Johan; Henning, Thomas [Max Planck Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg (Germany); Harvey, Paul M.; Evans II, Neal J. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Pinte, Christophe; Augereau, Jean-Charles; Menard, Francois [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041 (France); Merin, Bruno [Herschel Science Centre, European Space Agency (ESAC), P.O. Box 78, 28691 Villanueva de la Canada, Madrid (Spain); Najita, Joan, E-mail: lcieza@ifa.hawaii.edu [National Optical Astronomy Observatory, 950 N. Cherry Avenue, Tucson, AZ 86719 (United States)

    2011-11-10

    T Cha is a nearby (d {approx} 100 pc) transition disk known to have an optically thin gap separating optically thick inner and outer disk components. Huelamo et al. recently reported the presence of a low-mass object candidate within the gap of the T Cha disk, giving credence to the suspected planetary origin of this gap. Here we present the Herschel photometry (70, 160, 250, 350, and 500 {mu}m) of T Cha from the 'Dust, Ice, and Gas in Time' Key Program, which bridges the wavelength range between existing Spitzer and millimeter data and provide important constraints on the outer disk properties of this extraordinary system. We model the entire optical to millimeter wavelength spectral energy distribution (SED) of T Cha (19 data points between 0.36 and 3300 {mu}m without any major gaps in wavelength coverage). T Cha shows a steep spectral slope in the far-IR, which we find clearly favors models with outer disks containing little or no dust beyond {approx}40 AU. The full SED can be modeled equally well with either an outer disk that is very compact (only a few AU wide) or a much larger one that has a very steep surface density profile. That is, T Cha's outer disk seems to be either very small or very tenuous. Both scenarios suggest a highly unusual outer disk and have important but different implications for the nature of T Cha. Spatially resolved images are needed to distinguish between the two scenarios.

  15. Recurrent evolution of host and vector association in bacteria of the Borrelia burgdorferi sensu lato species complex.

    Science.gov (United States)

    Becker, Noémie S; Margos, Gabriele; Blum, Helmut; Krebs, Stefan; Graf, Alexander; Lane, Robert S; Castillo-Ramírez, Santiago; Sing, Andreas; Fingerle, Volker

    2016-09-15

    The Borrelia burgdorferi sensu lato (s.l.) species complex consists of tick-transmitted bacteria and currently comprises approximately 20 named and proposed genospecies some of which are known to cause Lyme Borreliosis. Species have been defined via genetic distances and ecological niches they occupy. Understanding the evolutionary relationship of species of the complex is fundamental to explaining patterns of speciation. This in turn forms a crucial basis to frame testable hypotheses concerning the underlying processes including host and vector adaptations. Illumina Technology was used to obtain genome-wide sequence data for 93 strains of 14 named genospecies of the B. burgdorferi species complex and genomic data already published for 18 additional strain (including one new species) was added. Phylogenetic reconstruction based on 114 orthologous single copy genes shows that the genospecies represent clearly distinguishable taxa with recent and still ongoing speciation events apparent in Europe and Asia. The position of Borrelia species in the phylogeny is consistent with host associations constituting a major driver for speciation. Interestingly, the data also demonstrate that vector associations are an additional driver for diversification in this tick-borne species complex. This is particularly obvious in B. bavariensis, a rodent adapted species that has diverged from the bird-associated B. garinii most likely in Asia. It now consists of two populations one of which most probably invaded Europe following adaptation to a new vector (Ixodes ricinus) and currently expands its distribution range. The results imply that genotypes/species with novel properties regarding host or vector associations have evolved recurrently during the history of the species complex and may emerge at any time. We suggest that the finding of vector associations as a driver for diversification may be a general pattern for tick-borne pathogens. The core genome analysis presented here

  16. Lyme disease caused by Borrelia burgdorferi with two homeologous 16S rRNA genes: a case report

    Directory of Open Access Journals (Sweden)

    Lee SH

    2016-04-01

    Full Text Available Sin Hang Lee,1,21Pathology Department, Milford Hospital, Milford, CT, USA; 2Milford Molecular Diagnostics, Milford, CT, USA Abstract: Lyme disease (LD, the most common tick-borne disease in North America, is believed to be caused exclusively by Borrelia burgdorferi sensu stricto and is usually diagnosed by clinical evaluation and serologic assays. As reported previously in a peer-reviewed article, a 13-year-old boy living in the Northeast of the USA was initially diagnosed with LD based on evaluation of his clinical presentations and on serologic test results. The patient was treated with a course of oral doxycycline for 28 days, and the symptoms resolved. A year later, the boy developed a series of unusual symptoms and did not attend school for 1 year. A LD specialist reviewed the case and found the serologic test band patterns nondiagnostic of LD. The boy was admitted to a psychiatric hospital. After discharge from the psychiatric hospital, a polymerase chain reaction test performed in a winter month when the boy was 16 years old showed a low density of B. burgdorferi sensu lato in the blood of the patient, confirmed by partial 16S rRNA (ribosomal RNA gene sequencing. Subsequent DNA sequencing analysis presented in this report demonstrated that the spirochete isolate was a novel strain of B. burgdorferi with two homeologous 16S rRNA genes, which has never been reported in the world literature. This case report shows that direct DNA sequencing is a valuable tool for reliable molecular diagnosis of Lyme and related borrelioses, as well as for studies of the diversity of the causative agents of LD because LD patients infected by a rare or novel borrelial variant may produce an antibody pattern that can be different from the pattern characteristic of an infection caused by a typical B. burgdorferi sensu stricto strain. Keywords: Lyme disease, Borrelia burgdorferi, homeologous 16S rRNA genes, DNA sequencing

  17. The role of Ixodes scapularis, Borrelia burgdorferi and wildlife hosts in Lyme disease prevalence: A quantitative review.

    Science.gov (United States)

    Halsey, Samniqueka J; Allan, Brian F; Miller, James R

    2018-04-16

    Due to the ongoing expansion of Ixodes scapularis (blacklegged tick) throughout the northeastern and midwestern United States, there is need to identify the role wildlife hosts play in the establishment and maintenance of tick populations. To quantify and synthesize the patterns of I. scapularis and Borrelia burgdorferi sensu stricto and sensu lato prevalence relative to wildlife hosts, we reviewed the findings of independent studies conducted throughout the United States. We performed a comprehensive literature search from 1970 to 2017 using the ISS Web of Science Core Collection and the keywords "Ixodes scapularis," "Ixodes dammini" and "Borrelia burgdorferi." We identified 116 studies for inclusion in our meta-analysis, with 187,414 individual wildlife hosts captured and examined for I. scapularis and either the host or ticks collected subsequently tested for B. burgdorferi. We found that only 13% of the wildlife mammals sampled comprised species other than Odocoileus virginianus (white-tailed deer) and Peromyscus leucopus (white-footed mouse). To examine whether there were regional differences between the Northeast, Midwest and the Southeast U.S. in I. scapularis infestation rates on wildlife hosts, we used general linear models (glm), with post hoc pairwise comparisons. In most cases, detection of I. scapularis and B. burgdorferi was significantly higher in the Northeast than the Midwest. Using data on host-specific I. scapularis infestation prevalence, B. burgdorferi prevalence in feeding larvae, and host permissiveness, we developed an epizootiological model to determine the relative contributions of individual hosts to B. burgdorferi-infected nymphs. Our model provides additional evidence that wildlife hosts other than P. leucopus may contribute more to Lyme disease risk than commonly thought. To aid in understanding the ecology of Lyme disease, we propose that additional studies sample non-Peromyscus spp. hosts to obtain more detailed tick and pathogen

  18. Closely-related Borrelia burgdorferi (sensu stricto) strains exhibit similar fitness in single infections and asymmetric competition in multiple infections.

    Science.gov (United States)

    Rynkiewicz, Evelyn C; Brown, Julia; Tufts, Danielle M; Huang, Ching-I; Kampen, Helge; Bent, Stephen J; Fish, Durland; Diuk-Wasser, Maria A

    2017-02-06

    Wild hosts are commonly co-infected with complex, genetically diverse, pathogen communities. Competition is expected between genetically or ecologically similar pathogen strains which may influence patterns of coexistence. However, there is little data on how specific strains of these diverse pathogen species interact within the host and how this impacts pathogen persistence in nature. Ticks are the most common disease vector in temperate regions with Borrelia burgdorferi, the causative agent of Lyme disease, being the most common vector-borne pathogen in North America. Borrelia burgdorferi is a pathogen of high public health concern and there is significant variation in infection phenotype between strains, which influences predictions of pathogen dynamics and spread. In a laboratory experiment, we investigated whether two closely-related strains of B. burgdorferi (sensu stricto) showed similar transmission phenotypes, how the transmission of these strains changed when a host was infected with one strain, re-infected with the same strain, or co-infected with two strains. Ixodes scapularis, the black-legged tick, nymphs were used to sequentially infect laboratory-bred Peromyscus leucopus, white-footed mice, with one strain only, homologous infection with the same stain, or heterologous infection with both strains. We used the results of this laboratory experiment to simulate long-term persistence and maintenance of each strain in a simple simulation model. Strain LG734 was more competitive than BL206, showing no difference in transmission between the heterologous infection groups and single-infection controls, while strain BL206 transmission was significantly reduced when strain LG734 infected first. The results of the model show that this asymmetry in competition could lead to extinction of strain BL206 unless there was a tick-to-host transmission advantage to this less competitive strain. This asymmetric competitive interaction suggests that strain identity and

  19. Statistics of the outer radiation belt

    International Nuclear Information System (INIS)

    Rodgers, D.J.; Johnstone, A.D.

    1996-01-01

    The highly variable electron flux levels in the outer radiation belt come about by competition between time-dependent source and loss mechanisms. In order to identify some of the different mechanisms involved, we examine the statistics of the variability of fluxes at geostationary orbit. Data from the SEM-2 analyzer on Meteosat-3 and from GOES-7 are used. Correlation analysis is used to find time-delays between changes in flux at different energies. We see that low energy flux is added to this region during sub-storms and that higher energy fluxes appear after 2 or 3 days. Whilst the timescale for this process is brief compared to a complete cycle of the open-quote Recirculation close-quote energization process, it is consistent with the timescale of its final step endash outward radial diffusion. By isolating periods when no new injection of plasma occurs, we make an assessment of flux loss rates in a quiet magnetosphere. copyright 1996 American Institute of Physics

  20. Evaluation of recomBead Borrelia. Quantitative analysis using 13 antigens for IgM and IgG. Do Borrelia IgM antibodies have diagnostic use in Northern Scandinavia? - A comparison of sero-reactivity of samples from Åland and Denmark

    DEFF Research Database (Denmark)

    Dessau, Ram; Møller, Jens Kjølseth

    2012-01-01

    Evaluering af recomBead borrelia. Ny multiplex metode. Der blev præsenteret overvejelser om hvordan man skal score den den store mængde resultater for at opnå optimal diagnostisk diskriminations evne. Disse metode overvejelser er var vigtige, da det samme kit afprøves både to steder i Sverige ogs...

  1. Radiolysis of Amino Acids in Outer Solar-System Ice Analogs

    Science.gov (United States)

    Gerakines, Perry A.; Hudson, Reggie L.

    2011-01-01

    Amino acids have been found in cometary dust particles and in the organic component of meteorites. These molecules, important for pre-biotic chemistry and for active biological systems, might be formed in cold planetary or interstellar environments and then delivered to H20-rich surfaces in the outer solar system. Many models for the availability of organic species on Earth and elsewhere depend on the ability of these molecules to survive in radiation-rich space environments. This poster presents results of O.8-MeV proton radiolysis of ice films at lS-140K. using infrared spectroscopy, the destruction rates of glycine, alanine, and phenylalanine have been determined for both pure films and those containing amino acids diluted in H2o. our results are discussed in terms of the survivability of these molecules in the icy surfaces present in the outer solar system and the possibility of their detection by instruments on board the New Horizons spacecraft

  2. 46 CFR 154.170 - Outer hull steel plating.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Outer hull steel plating. 154.170 Section 154.170... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Hull Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the...

  3. Outer space and nuclear deterrence: problems and prospects

    International Nuclear Information System (INIS)

    Gasparini Alves, P.

    1993-01-01

    The presentation deals with the role of outer-space applications and prospects for near future developments in nuclear deterrence. Outer space capabilities of United Sates, Russian Federation, Belarus, Kazakhstan, Ukraine, China, and United Kingdom as well as other states are analyzed. Conceptual problems of offensive and defensive doctrines are reviewed together with legal implications

  4. Newborns' Face Recognition: Role of Inner and Outer Facial Features

    Science.gov (United States)

    Turati, Chiara; Macchi Cassia, Viola; Simion, Francesca; Leo, Irene

    2006-01-01

    Existing data indicate that newborns are able to recognize individual faces, but little is known about what perceptual cues drive this ability. The current study showed that either the inner or outer features of the face can act as sufficient cues for newborns' face recognition (Experiment 1), but the outer part of the face enjoys an advantage…

  5. Proteomics of Aggregatibacter actinomycetemcomitans Outer Membrane Vesicles.

    Directory of Open Access Journals (Sweden)

    Thomas Kieselbach

    Full Text Available Aggregatibacter actinomycetemcomitans is an oral and systemic pathogen associated with aggressive forms of periodontitis and with endocarditis. Outer membrane vesicles (OMVs released by this species have been demonstrated to deliver effector proteins such as cytolethal distending toxin (CDT and leukotoxin (LtxA into human host cells and to act as triggers of innate immunity upon carriage of NOD1- and NOD2-active pathogen-associated molecular patterns (PAMPs. To improve our understanding of the pathogenicity-associated functions that A. actinomycetemcomitans exports via OMVs, we studied the proteome of density gradient-purified OMVs from a rough-colony type clinical isolate, strain 173 (serotype e using liquid chromatography-tandem mass spectrometry (LC-MS/MS. This analysis yielded the identification of 151 proteins, which were found in at least three out of four independent experiments. Data are available via ProteomeXchange with identifier PXD002509. Through this study, we not only confirmed the vesicle-associated release of LtxA, and the presence of proteins, which are known to act as immunoreactive antigens in the human host, but we also identified numerous additional putative virulence-related proteins in the A. actinomycetemcomitans OMV proteome. The known and putative functions of these proteins include immune evasion, drug targeting, and iron/nutrient acquisition. In summary, our findings are consistent with an OMV-associated proteome that exhibits several offensive and defensive functions, and they provide a comprehensive basis to further disclose roles of A. actinomycetemcomitans OMVs in periodontal and systemic disease.

  6. Tick-Borne Relapsing Fever Imported from West Africa: Diagnosis by Quantitative Buffy Coat Analysis and In Vitro Culture of Borrelia crocidurae

    OpenAIRE

    van Dam, Alje P.; van Gool, Tom; Wetsteyn, José C. F. M.; Dankert, Jacob

    1999-01-01

    West African tick-borne relapsing fever (TBRF) is difficult to diagnose due to the low number of spirochetes in the bloodstream of patients. Previously, the causative microorganism, Borrelia crocidurae, had never been cultured in vitro. TBRF was rapidly diagnosed for two patients returning from western Africa with fever of unknown origin by quantitative buffy coat (QBC) analysis. Diagnosis was confirmed by intraperitoneal inoculation of blood specimens from patients into laboratory mice. In v...

  7. Detection of Borrelia bissetii in the South Bohemia region of the Czech Republic: cases of single and multiple infections in humans

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Piskunova, N.; Růžek, Daniel; Grubhoffer, Libor

    2008-01-01

    Roč. 14, S7 (2008), S109-S110 ISSN 1198-743X. [ECCMID /18./. 19.04.2008-22.04.2008, Barcelona] R&D Projects: GA MŠk(CZ) LC06009; GA ČR GD524/03/H133; GA ČR(CZ) GA524/06/1479 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lyme disease * Borrelia bissettii * causative agent * human samples Subject RIV: EC - Immunology

  8. Detection of Borrelia bissettii in cardiac valve tissue of a patient with endocarditis and aortic valve stenosis in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Mokráček, A.; Piskunova, N.; Růžek, Daniel; Mallátová, N.; Grubhoffer, Libor

    2008-01-01

    Roč. 46, č. 10 (2008), s. 3540-3543 ISSN 0095-1137 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GD524/03/H133; GA ČR(CZ) GA524/06/1479 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lyme disease * Borrelia bissettii * carditis * causative agent Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.945, year: 2008

  9. 北海道におけるBorrelia spp.の伝播に対する鹿の役割 [全文の要約

    OpenAIRE

    李, 景利

    2014-01-01

    The intent of this research was to describe the role of deer in the transmission of different species of Borrelia spp. Sika deer (Cervus nippon yesoensis) are the hosts of ticks of various species and stages in Hokkaido. Deer overpopulation has caused problems with forestry and agricultural production. The potential of deer involvement in zoonoses is also being watched. In this study, deer caught in the nuisance control scheme and ticks collected from deer and the field were tested to detect ...

  10. Validate or falsify: Lessons learned from a microscopy method claimed to be useful for detecting Borrelia and Babesia organisms in human blood

    Czech Academy of Sciences Publication Activity Database

    Aase, A.; Hajdušek, Ondřej; Øines, Ø.; Quarsten, H.; Wilhelmsson, P.; Herstad, T.K.; Kjelland, V.; Šíma, Radek; Jalovecká, Marie; Lindgren, P-E.; Aaberge, I.S.

    2016-01-01

    Roč. 48, č. 6 (2016), s. 411-419 ISSN 2374-4235 R&D Projects: GA ČR GP13-27630P; GA ČR GP13-12816P EU Projects: European Commission(XE) 316304 - MODBIOLIN Institutional support: RVO:60077344 Keywords : Lyme disease * Borrelia burgdorferi sensu lato * babesiosis * Babesia spp. * Lyme borreliosis * PCR * microscopy Subject RIV: EC - Immunology Impact factor: 1.119, year: 2016

  11. Exposure to hepatitis E virus, hepatitis A virus and Borrelia spp. infections in forest rangers from a single forest district in western Poland.

    Science.gov (United States)

    Bura, Maciej; Bukowska, Alicja; Michalak, Michał; Bura, Aleksandra; Nawrocki, Mariusz J; Karczewski, Marek; Mozer-Lisewska, Iwona

    2018-03-13

    Hepatitis E virus (HEV) infection is an emerging problem in developed countries. At least 2 zoonotic genotypes of the virus (HEV-3 and HEV-4) infect human beings. There are some data suggesting that forest rangers (FRs) can be at a higher risk of contact with HEV. The aim of this study was to assess the prevalence of HEV exposure markers in FRs from a single forest district in Greater Poland in relation to anti-HAV (hepatitis A virus) IgG, and anti-Borrelia spp. IgM and IgG antibodies. In total, 138 participants (48 FRs and 90 blood donors - BDs) were tested for anti-HEV IgM and IgG (EUROIMMUN Medizinische Labordiagnostika AG, Luebeck, Germany) and 96 individuals (48 FRs and 48 BDs) were tested for anti-HAV IgG (ARCHITECT immunoassays, Abbott Laboratories, Wiesbaden, Germany); anti-Borrelia IgM and IgG (EUROIMMUN kits) were assessed in FRs only. Anti-HEV markers were detected in 3 participants (2.2%; IgM in 1 FR, IgG in 2 BDs), less frequently than anti-HAV (16 out of 96 individuals, about 17%; FRs 19% vs BDs 15%) or anti-Borrelia antibodies (18 out of 48 individuals, 37.5%) (p < 0.0001 for both). Older study participants (≥45 years of age) were more frequently HAV-seropositive (29% vs 4% of the younger individuals; p = 0.0012). We failed to unequivocally prove HEV exposure in FRs. The HAV seroprevalence in this study paralleled the situation in the general population. Exposure to Borrelia spp. in FRs was common.

  12. Prevalence of Borrelia burgdorferi in ticks removed from skin of people and circumstances of being bitten – research from the area of Poland, 2012–2014

    Directory of Open Access Journals (Sweden)

    Edyta Gałęziowska

    2018-03-01

    Infestation of ticks infected with Lyme disease spirochete in this study proved to be variable and depend on the season, the area of tick attack and the region in Poland. The results of the study clearly show that ticks infected with Borrelia burgdorferi inhabit all regions of Poland. The results are consistent with National Institute of Hygiene data which indicates that Lyme disease cases are recorded in all regions of Poland.

  13. Tick saliva affects both proliferation and distribution of Borrelia burgdorferi spirochetes in mouse organs and increases transmission of spirochetes to ticks

    Czech Academy of Sciences Publication Activity Database

    Horká, Helena; Černá-Kýčková, Kateřina; Skallová, Anna; Kopecký, Jan

    2009-01-01

    Roč. 299, č. 5 (2009), s. 373-380 ISSN 1438-4221 R&D Projects: GA AV ČR IAA600960811; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z60220518 Keywords : Borrelia burgdorferi * Ixodes ricinus * saliva-activated transmission * real-time PCR Subject RIV: EC - Immunology Impact factor: 2.802, year: 2009

  14. Evaluation of the possibility to use thick slabs of reconstructed outer breast tomosynthesis slice images

    Science.gov (United States)

    Petersson, Hannie; Dustler, Magnus; Tingberg, Anders; Timberg, Pontus

    2016-03-01

    The large image volumes in breast tomosynthesis (BT) have led to large amounts of data and a heavy workload for breast radiologists. The number of slice images can be decreased by combining adjacent image planes (slabbing) but the decrease in depth resolution can considerably affect the detection of lesions. The aim of this work was to assess if thicker slabbing of the outer slice images (where lesions seldom are present) could be a viable alternative in order to reduce the number of slice images in BT image volumes. The suggested slabbing (an image volume with thick outer slabs and thin slices between) were evaluated in two steps. Firstly, a survey of the depth of 65 cancer lesions within the breast was performed to estimate how many lesions would be affected by outer slabs of different thicknesses. Secondly, a selection of 24 lesions was reconstructed with 2, 6 and 10 mm slab thickness to evaluate how the appearance of lesions located in the thicker slabs would be affected. The results show that few malignant breast lesions are located at a depth less than 10 mm from the surface (especially for breast thicknesses of 50 mm and above). Reconstruction of BT volumes with 6 mm slab thickness yields an image quality that is sufficient for lesion detection for a majority of the investigated cases. Together, this indicates that thicker slabbing of the outer slice images is a promising option in order to reduce the number of slice images in BT image volumes.

  15. Search for Borrelia sp. in ticks collected from potential reservoirs in an urban forest reserve in the State of Mato Grosso do Sul, Brazil: a short report

    Directory of Open Access Journals (Sweden)

    IP da Costa

    2002-07-01

    Full Text Available A total of 128 ticks of the genus Amblyomma were recovered from 5 marsupials (Didelphis albiventris - with 4 recaptures - and 17 rodents (16 Bolomys lasiurus and 1 Rattus norvegicus captured in an urban forest reserve in Campo Grande, State of Mato Grosso do Sul, Brazil. Of the ticks collected, 95 (78.9% were in larval form and 22 (21.1% were nymphs; the only adult (0.8% was identified as A. cajennense. Viewed under dark-field microscopy in the fourth month after seeding, 9 cultures prepared from spleens and livers of the rodents, blood of the marsupials, and macerates of Amblyomma sp. nymphs revealed spiral-shaped, spirochete-like structures resembling those of Borrelia sp. Some of them showed little motility, while others were non-motile. No such structures could be found either in positive Giemsa-stained culture smears or under electron microscopy. No PCR amplification of DNA from those cultures could be obtained by employing Leptospira sp., B. burgdorferi, and Borrelia sp. primers. These aspects suggest that the spirochete-like structures found in this study do not fit into the genera Borrelia or Leptospira, requiring instead to be isolated for proper identification.

  16. Molecular Survey on Rickettsia spp., Anaplasma phagocytophilum, Borrelia burgdorferi Sensu Lato, and Babesia spp. in Ixodes ricinus Ticks Infesting Dogs in Central Italy.

    Science.gov (United States)

    Morganti, Giulia; Gavaudan, Stefano; Canonico, Cristina; Ravagnan, Silvia; Olivieri, Emanuela; Diaferia, Manuela; Marenzoni, Maria Luisa; Antognoni, Maria Teresa; Capelli, Gioia; Silaghi, Cornelia; Veronesi, Fabrizia

    2017-11-01

    Dogs are a common feeding hosts for Ixodes ricinus and may act as reservoir hosts for zoonotic tick-borne pathogens (TBPs) and as carriers of infected ticks into human settings. The aim of this work was to evaluate the presence of several selected TBPs of significant public health concern by molecular methods in I. ricinus recovered from dogs living in urban and suburban settings in central Italy. A total of 212 I. ricinus specimens were collected from the coat of domestic dogs. DNA was extracted from each specimen individually and tested for Rickettsia spp., Borrelia burgdorferi sensu lato, Babesia spp., and Anaplasma phagocytophilum, using real-time and conventional PCR protocols, followed by sequencing. Sixty-one ticks (28.8%) tested positive for TBPs; 57 samples were infected by one pathogen, while four showed coinfections. Rickettsia spp. was detected in 39 specimens (18.4%), of which 32 were identified as Rickettsia monacensis and seven as Rickettsia helvetica. Twenty-two samples (10.4%) tested positive for A. phagocytophilum; Borrelia lusitaniae and Borrelia afzelii were detected in two specimens and one specimen, respectively. One tick (0.5%) was found to be positive for Babesia venatorum (EU1). Our findings reveal the significant exposure of dogs to TBPs of public health concern and provide data on the role of dogs in the circulation of I. ricinus-borne pathogens in central Italy.

  17. The Eccentric Kozai-Lidov Mechanism for Outer Test Particle

    Science.gov (United States)

    Naoz, Smadar; Li, Gongjie; Zanardi, Macarena; de Elía, Gonzalo Carlos; Di Sisto, Romina P.

    2017-07-01

    The secular approximation of the hierarchical three body systems has been proven to be very useful in addressing many astrophysical systems, from planets to stars to black holes. In such a system, two objects are on a tight orbit and the tertiary is on a much wider orbit. Here, we study the dynamics of a system by taking the tertiary mass to zero and solve the hierarchical three body system up to the octupole level of approximation. We find a rich dynamics that the outer orbit undergoes due to gravitational perturbations from the inner binary. The nominal result of the precession of the nodes is mostly limited for the lowest order of approximation; however, when the octupole level of approximation is introduced, the system becomes chaotic, as expected, and the tertiary oscillates below and above 90°, similarly to the non-test particle flip behavior. We provide the Hamiltonian of the system and investigate the dynamics of the system from the quadrupole to the octupole level of approximations. We also analyze the chaotic and quasi-periodic orbital evolution by studying the surfaces of sections. Furthermore, including general relativity, we showcase the long-term evolution of individual debris disk particles under the influence of a far-away interior eccentric planet. We show that this dynamics can naturally result in retrograde objects and a puffy disk after a long timescale evolution (a few Gyr) for initially aligned configuration.

  18. Geocosmos: mapping outer space into a hollow earth

    Energy Technology Data Exchange (ETDEWEB)

    Abdelkader, M.A. (Alexandria, Egypt)

    1983-04-01

    The authors regards the earth's surface as a sphere and applies a purely mathematical mapping taking outer space in the Copernican universe (C) into a hollow earth, Geocosmos (G). The enormous galaxies and other remote objects are mapped inside as microscopic objects, and the moon as by far the largest of the celestial objects, all of which revolve daily around the earth's axis. Straight rays of light are mapped as arcs of circles, so that all celestial phenomena appear to inside observers in G just as they do to outside observers in C. He next considers the hypothesis that, conversely, the actual universe is this finite G. Then there seems to be no way of testing this, except by drilling a hole right through the earth's centre. However, in C the origin of cosmic rays of super-high energies is very controversial, whereas in G it is unequivocal. The idea of G was first conceived qualitatively by Karl E. Neupert in 1900; this revival is somewhat different. The main appeal of G stems from the very grave difficulty of believing in the fantastic vastness of C, and the consequent reduction of the earth to an infinitesimal.

  19. A geocosmos: mapping outer space into a hollow earth

    International Nuclear Information System (INIS)

    Abdelkader, M.A.

    1983-01-01

    The authors regards the earth's surface as a sphere and applies a purely mathematical mapping taking outer space in the Copernican universe (C) into a hollow earth, Geocosmos (G). The enormous galaxies and other remote objects are mapped inside as microscopic objects, and the moon as by far the largest of the celestial objects, all of which revolve daily around the earth's axis. Straight rays of light are mapped as arcs of circles, so that all celestial phenomena appear to inside observers in G just as they do to outside observers in C. He next considers the hypothesis that, conversely, the actual universe is this finite G. Then there seems to be no way of testing this, except by drilling a hole right through the earth's centre. However, in C the origin of cosmic rays of super-high energies is very controversial, whereas in G it is unequivocal. The idea of G was first conceived qualitatively by Karl E. Neupert in 1900; this revival is somewhat different. The main appeal of G stems from the very grave difficulty of believing in the fantastic vastness of C, and the consequent reduction of the earth to an infinitesimal. (Auth.)

  20. The Eccentric Kozai–Lidov Mechanism for Outer Test Particle

    Energy Technology Data Exchange (ETDEWEB)

    Naoz, Smadar [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Li, Gongjie [Harvard Smithsonian Center for Astrophysics, Institute for Theory and Computation, 60 Garden Street, Cambridge, MA 02138 (United States); Zanardi, Macarena; De Elía, Gonzalo Carlos; Di Sisto, Romina P., E-mail: snaoz@astro.ucla.edu [Instituto de Astrofísica de La Plata, CCT La Plata-CONICET-UNLP Paseo del Bosque S/N (1900), La Plata (Argentina)

    2017-07-01

    The secular approximation of the hierarchical three body systems has been proven to be very useful in addressing many astrophysical systems, from planets to stars to black holes. In such a system, two objects are on a tight orbit and the tertiary is on a much wider orbit. Here, we study the dynamics of a system by taking the tertiary mass to zero and solve the hierarchical three body system up to the octupole level of approximation. We find a rich dynamics that the outer orbit undergoes due to gravitational perturbations from the inner binary. The nominal result of the precession of the nodes is mostly limited for the lowest order of approximation; however, when the octupole level of approximation is introduced, the system becomes chaotic, as expected, and the tertiary oscillates below and above 90°, similarly to the non-test particle flip behavior. We provide the Hamiltonian of the system and investigate the dynamics of the system from the quadrupole to the octupole level of approximations. We also analyze the chaotic and quasi-periodic orbital evolution by studying the surfaces of sections. Furthermore, including general relativity, we showcase the long-term evolution of individual debris disk particles under the influence of a far-away interior eccentric planet. We show that this dynamics can naturally result in retrograde objects and a puffy disk after a long timescale evolution (a few Gyr) for initially aligned configuration.

  1. Soluble cysteine-rich tick saliva proteins Salp15 and Iric-1 from E. coli

    OpenAIRE

    Kolb, Philipp; Vorreiter, Jolanta; Habicht, J?ri; Bentrop, Detlef; Wallich, Reinhard; Nassal, Michael

    2014-01-01

    Ticks transmit numerous pathogens, including borreliae, which cause Lyme disease. Tick saliva contains a complex mix of anti-host defense factors, including the immunosuppressive cysteine-rich secretory glycoprotein Salp15 from Ixodes scapularis ticks and orthologs like Iric-1 from Ixodes ricinus. All tick-borne microbes benefit from the immunosuppression at the tick bite site; in addition, borreliae exploit the binding of Salp15 to their outer surface protein C (OspC) for enhanced transmissi...

  2. Pressure Gradients in the Inner Surf and Outer Swash Zone

    Science.gov (United States)

    Kidwell, A.; Puleo, J. A.; Torres-Freyermuth, A.

    2010-12-01

    The swash zone is a highly dynamic region of the beach profile. Although there has been significant progression in understanding the complex hydrodynamics of the swash zone, an improvement in the understanding of the sediment transport mechanisms deserves further investigation. Prior studies have demonstrated that the existing formulations derived from the energetics-type formulation do not accurately and consistently predict sediment transport. Thus, measurements and numerical modeling can contribute in the improvement of the current predictive capability of sediment transport. A potential enhancement to nearshore sediment transport is the horizontal pressure gradient. However, measuring the dynamic pressure gradient in nearshore flows is a difficult task. For instance, standard pressure sensors are generally ill-suited for this type of measurement in shallow swash flows due to the obstructing size of the sensor and the potential for flow interference. With improved measurement apparati and techniques, it is possible to obtain measurements of the horizontal pressure gradient. Our current research includes laboratory and numerical model investigation of the horizontal pressure gradient in the inner surf and outer swash zone. An inexpensive differential pressure gauge is employed allowing for a pressure port on the order of 2 mm diameter. Four pressure sensor pairs are installed 1 cm above the bed with a cross-shore spacing of 8 cm. The sensors are deployed just outside of and at various locations within the outer swash zone to determine spatio-temporal pressure variations. The measurement of total pressure coupled with the corresponding free surface measurements from co-located capacitance wave gauges yields time series of the hydrostatic and dynamic pressure and pressure gradients. A VOF-type RANS model is employed in this investigation. Firstly, the numerical model is validated with swash measurements. Then, model simulations will be performed in order to

  3. Quantitative kinetic analysis of blood vessels in the outer membranes of chronic subdural hematomas

    International Nuclear Information System (INIS)

    Mori, Kentaro; Adachi, Keiji; Cho, Kajin; Ishimaru, Sumio; Maeda, Minoru

    1998-01-01

    Dynamic biologic modeling was used to calculate the transfer rate constant for gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA) and capillary permeability in the outer membrane of chronic subdural hematomas and effusions. Following intravenous Gd-DTPA injection, Gd concentrations in the subdural fluid and in timed arterial blood samples were measured by ion-coupled plasma emission spectrometry in 53 chronic subdural hematomas and 18 chronic subdural effusions. The capillary surface area in outer membrane was assessed morphometrically. Transfer rate constants for subdural hematomas and subdural effusions were 12.4±1.0 and 20.6±1.7 (x 10 -4 )min -1 , respectively. Capillary permeabilities for subdural hematomas and subdural effusions were 16±1.2 and 19±3.7 ml·min -1 (mm 2 /mm 3 ) -1 , respectively. The capillary surface areas for subdural hematomas and subdural effusions were 48±3 and 77±10 mm 2 /mm 3 , respectively. The high degree of infiltration of Gd into subdural effusions reflects the high capillary surface area in the outer membrane rather than greater permeability of individual capillaries. The value of transfer rate constant was correlated inversely with the duration of the chronic subdural fluid collection. Immature outer membrane has a high transfer rate constant which allows extravasation of plasma components into the subdural space, resulting in increasing volume of the subdural effusion. Delayed magnetic resonance imaging following Gd administration may be clinically useful for estimating the age of chronic subdural fluid accumulations. (author)

  4. Nodulation outer proteins: double-edged swords of symbiotic rhizobia.

    Science.gov (United States)

    Staehelin, Christian; Krishnan, Hari B

    2015-09-15

    Rhizobia are nitrogen-fixing bacteria that establish a nodule symbiosis with legumes. Nodule formation depends on signals and surface determinants produced by both symbiotic partners. Among them, rhizobial Nops (nodulation outer proteins) play a crucial symbiotic role in many strain-host combinations. Nops are defined as proteins secreted via a rhizobial T3SS (type III secretion system). Functional T3SSs have been characterized in many rhizobial strains. Nops have been identified using various genetic, biochemical, proteomic, genomic and experimental approaches. Certain Nops represent extracellular components of the T3SS, which are visible in electron micrographs as bacterial surface appendages called T3 (type III) pili. Other Nops are T3 effector proteins that can be translocated into plant cells. Rhizobial T3 effectors manipulate cellular processes in host cells to suppress plant defence responses against rhizobia and to promote symbiosis-related processes. Accordingly, mutant strains deficient in synthesis or secretion of T3 effectors show reduced symbiotic properties on certain host plants. On the other hand, direct or indirect recognition of T3 effectors by plant cells expressing specific R (resistance) proteins can result in effector triggered defence responses that negatively affect rhizobial infection. Hence Nops are double-edged swords that may promote establishment of symbiosis with one legume (symbiotic factors) and impair symbiotic processes when bacteria are inoculated on another legume species (asymbiotic factors). In the present review, we provide an overview of our current understanding of Nops. We summarize their symbiotic effects, their biochemical properties and their possible modes of action. Finally, we discuss future perspectives in the field of T3 effector research. © 2015 Authors; published by Portland Press Limited.

  5. Prevention of an arms race in outer space

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The space age may be the to have begun in 1957, when for the first time a man-made object was lofted into orbit round the Earth. Since that date, the new problems of outer space have been discussed in the United Nations, particularly in the General Assembly, in the Committee on the Peaceful Uses of Outer Space and its subsidiary bodies, and in the Conference on Disarmament. The discussions have contributed to the conclusion of a number of international agreements concerning both military and peaceful aspects of the use of outer space. This paper reports that according to the 1967 Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, known as the outer space Treaty, outer space, including the moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means (article II), and the parties undertake not to place in orbit around the earth any objects carrying nuclear weapons or any other kinds of weapons of ass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner (article IV). Detailed norms for States' actions in this environment are included in the 1979 Agreement Governing the Activities of States on the Moon and other Celestial Bodies to ensure that the Moon and other celestial bodies within the solar system, other than Earth, are used exclusively for peaceful purposes

  6. Legal Provisions Applicable to the Definition of Outer Space

    Science.gov (United States)

    Thorin, T.

    2002-01-01

    and decreeing the basic principle that no state can make claims to sovereignty or territory in space. This is followed by the Agreement of 11th September 1984 which governs the activities of states on the Moon and other celestial bodies. There are also three multilateral agreements which provide guiding principles in three specific areas: the Agreement on the Rescue and Return of Astronauts; the Convention on International Liability for Damage Caused by Space Objects; and, the Convention on Registration of Objects Launched into Outer Space. We shall then discuss other sources of law which also contribute towards defining the notion of space. These are essentially doctrinal positions which surface from the fundamental debate among legal experts divided between "functionalists" and "spacialists", which discussion is part of the general economic framework of international law, and considering naturally that Space law is an integral part of this framework. We shall also examine, as mentioned previously, the position taken by the various political and thus economic players in the international arena and we shall see that their somewhat diverging conceptions are often legitimised by very concrete concerns, far removed from theoretical debates, contributing to the development of international law. Finally, this will lead us to consider the pragmatic approach to such a problem, by discussing the various applications of legitimacy in demarcating space. So, we will among others discuss whether it is feasible to study a given territory without the permission of the country concerned; if "forbidden" orbits exist; in particular considering frequencies allocations and, of course, the simple right of flying and crossing, by shuttle designed vehicles both plane and rocket, over various states and their upper areas. In summary, the purpose of this paper is to determine when space law takes over from air law.

  7. Outer membrane biogenesis in Helicobacter pylori: A deviation from the paradigm

    Directory of Open Access Journals (Sweden)

    George W. Liechti

    2012-04-01

    Full Text Available The bacterial pathogen Helicobacter pylori is capable of colonizing the gastric mucosa of the human stomach using a variety of factors associated with or secreted from its outer membrane (OM. Lipopolysaccharide (LPS and numerous outer membrane proteins have been shown to be involved in adhesion and immune stimulation/evasion. Many of these factors are essential for colonization and/or pathogenesis in a variety of animal models. Despite this wide array of potential targets present on the bacterial surface, the ability of H. pylori to vary its outer membrane profile limits the effectiveness of vaccines that use any single one of these components. However, it has become evident that the proteins comprising the complexes that transport the majority of these molecules to the OM are highly conserved and often essential. The field of membrane biogenesis has progressed remarkably in the last few years, and the possibility now exists for targeting the mechanisms by which β-barrel proteins, lipoproteins, and LPS are transported to the OM, resulting in loss of bacterial fitness and significant altering of membrane permeability. In this review, the OM transport machinery for LPS, lipoproteins, and outer membrane proteins are discussed. While the principal investigations of these transport mechanisms have been conducted in Escherichia coli and Neisseria meningitidis, here these systems will be presented in the genetic context of ε- proteobacteria. Bioinformatic analysis reveals that minimalist genomes, such as that of Helicobacter pylori, offer insight into the smallest number of components required for these essential pathways to function. Interestingly, in the majority of ε-proteobacteria, while the inner and outer membrane associated apparatus of LPS, lipoprotein, and OM protein transport pathways appear to all be intact, most of the components associated with the periplasmic compartment are either missing or are almost unrecognizable when compared to

  8. Structural Aspects of Bacterial Outer Membrane Protein Assembly.

    Science.gov (United States)

    Calmettes, Charles; Judd, Andrew; Moraes, Trevor F

    2015-01-01

    The outer membrane of Gram-negative bacteria is predominantly populated by β-Barrel proteins and lipid anchored proteins that serve a variety of biological functions. The proper folding and assembly of these proteins is essential for bacterial viability and often plays a critical role in virulence and pathogenesis. The β-barrel assembly machinery (Bam) complex is responsible for the proper assembly of β-barrels into the outer membrane of Gram-negative bacteria, whereas the localization of lipoproteins (Lol) system is required for proper targeting of lipoproteins to the outer membrane.

  9. The use of paraffin wax in a new solar cooker with inner and outer reflectors

    Directory of Open Access Journals (Sweden)

    Arabacigil Bihter

    2015-01-01

    Full Text Available In this paper, the potential use and effectiveness of paraffin wax in a new solar cooker was experimentally investigated during daylight and late evening hours. For these experiments, a cooker having an inner reflecting surface was designed, constructed by filling paraffin wax and metal shavings. The side- and sub-surface temperatures of the paraffin wax in the cooker are measured in the summer months of June and July. The thermal efficiency of the cooker was tested on different conditions. The results show that the optimum angle of the outer reflector is 30°. Here, the peak temperature of the paraffin wax in the solar cooker was 83.4 °C. The average solar radiation reflected makes a contribution of 9.26% to the temperature of paraffin wax with the outer reflector. The solar cooker with the outer reflector angle of 30° receives also reflected radiation from the inner reflectors. Besides, the heating time is decreased to approximately 1 hour. The designed solar cooker can be effectively used with 30.3% daily thermal efficiency and paraffin wax due to the amount of energy stored.

  10. Dual role of Fcγ receptors in host defense and disease in Borrelia burgdorferi-infected mice

    Directory of Open Access Journals (Sweden)

    Alexia Anne Belperron

    2014-06-01

    Full Text Available Arthritis in mice infected with the Lyme disease spirochete, Borrelia burgdorferi, results from the influx of innate immune cells responding to the pathogen in the joint and is influenced in part by mouse genetics. Production of inflammatory cytokines by innate immune cells in vitro is largely mediated by Toll-like receptor (TLR interaction with Borrelia lipoproteins, yet surprisingly mice deficient in TLR2 or the TLR signaling molecule MyD88 still develop arthritis comparable to that seen in wild type mice after B. burgdorferi infection. These findings suggest that other, MyD88-independent inflammatory pathways can contribute to arthritis expression. Clearance of B. burgdorferi is dependent on the production of specific antibody and phagocytosis of the organism. As Fc receptors (FcγR are important for IgG-mediated clearance of immune complexes and opsonized particles by phagocytes, we examined the role that FcγR play in host defense and disease in B. burgdorferi-infected mice. B. burgdorferi-infected mice deficient in the Fc receptor common gamma chain (FcεRγ-/- mice harbored ~10 fold more spirochetes than similarly infected wild type mice, and this was associated with a transient increase in arthritis severity. While the elevated pathogen burdens seen in B. burgdorferi-infected MyD88-/- mice were not affected by concomitant deficiency in FcγR, arthritis was reduced in FcεRγ-/-MyD88-/- mice in comparison to wild type or single knockout mice. Gene expression analysis from infected joints demonstrated that absence of both MyD88 and FcγR lowers mRNA levels of proteins involved in inflammation, including Cxcl1 (KC, Xcr1 (Gpr5, IL-1beta, and C reactive protein. Taken together, our results demonstrate a role for FcγR-mediated immunity in limiting pathogen burden and arthritis in mice during the acute phase of B. burgdorferi infection, and further suggest that this pathway contributes to the arthritis that develops in B. burgdorferi

  11. Atmospheric Mining in the Outer Solar System: Outer Planet Orbital Transfer and Lander Analyses

    Science.gov (United States)

    Palaszewski, Bryan

    2016-01-01

    Atmospheric mining in the outer solar system has been investigated as a means of fuel production for high energy propulsion and power. Fusion fuels such as Helium 3 (3He) and deuterium can be wrested from the atmospheres of Uranus and Neptune and either returned to Earth or used in-situ for energy production. Helium 3 and deuterium were the primary gases of interest with hydrogen being the primary propellant for nuclear thermal solid core and gas core rocket-based atmospheric flight. A series of analyses were undertaken to investigate resource capturing aspects of atmospheric mining in the outer solar system. This included the gas capturing rate, storage options, and different methods of direct use of the captured gases. While capturing 3He, large amounts of hydrogen and 4He are produced. Analyses of orbital transfer vehicles (OTVs), landers, and the issues with in-situ resource utilization (ISRU) mining factories are included. Preliminary observations are presented on near-optimal selections of moon base orbital locations, OTV power levels, and OTV and lander rendezvous points. For analyses of round trip OTV flights from Uranus to Miranda or Titania, a 10- Megawatt electric (MWe) OTV power level and a 200 metricton (MT) lander payload were selected based on a relative short OTV trip time and minimization of the number of lander flights. A similar optimum power level is suggested for OTVs flying from low orbit around Neptune to Thalassa or Triton. Several moon base sites at Uranus and Neptune and the OTV requirements to support them are also addressed.

  12. Outer hair cell piezoelectricity: frequency response enhancement and resonance behavior.

    Science.gov (United States)

    Weitzel, Erik K; Tasker, Ron; Brownell, William E

    2003-09-01

    Stretching or compressing an outer hair cell alters its membrane potential and, conversely, changing the electrical potential alters its length. This bi-directional energy conversion takes place in the cell's lateral wall and resembles the direct and converse piezoelectric effects both qualitatively and quantitatively. A piezoelectric model of the lateral wall has been developed that is based on the electrical and material parameters of the lateral wall. An equivalent circuit for the outer hair cell that includes piezoelectricity shows a greater admittance at high frequencies than one containing only membrane resistance and capacitance. The model also predicts resonance at ultrasonic frequencies that is inversely proportional to cell length. These features suggest all mammals use outer hair cell piezoelectricity to support the high-frequency receptor potentials that drive electromotility. It is also possible that members of some mammalian orders use outer hair cell piezoelectric resonance in detecting species-specific vocalizations.

  13. Inner and Outer Recursive Neural Networks for Chemoinformatics Applications.

    Science.gov (United States)

    Urban, Gregor; Subrahmanya, Niranjan; Baldi, Pierre

    2018-02-26

    Deep learning methods applied to problems in chemoinformatics often require the use of recursive neural networks to handle data with graphical structure and variable size. We present a useful classification of recursive neural network approaches into two classes, the inner and outer approach. The inner approach uses recursion inside the underlying graph, to essentially "crawl" the edges of the graph, while the outer approach uses recursion outside the underlying graph, to aggregate information over progressively longer distances in an orthogonal direction. We illustrate the inner and outer approaches on several examples. More importantly, we provide open-source implementations [available at www.github.com/Chemoinformatics/InnerOuterRNN and cdb.ics.uci.edu ] for both approaches in Tensorflow which can be used in combination with training data to produce efficient models for predicting the physical, chemical, and biological properties of small molecules.

  14. Photoreceptor atrophy in acute zonal occult outer retinopathy

    DEFF Research Database (Denmark)

    Zibrandtsen, N.; Munch, I.C.; Klemp, K.

    2006-01-01

    Purpose: To assess retinal morphology in acute zonal occult outer retinopathy (AZOOR). Methods: Three patients with a normal ophthalmoscopic fundus appearance, a history of photopsia, and visual field loss compatible with AZOOR were examined using optical coherence tomography, automated perimetry...

  15. The molecular mechanism of Zinc acquisition by the neisserial outer-membrane transporter ZnuD

    Science.gov (United States)

    Calmettes, Charles; Ing, Christopher; Buckwalter, Carolyn M.; El Bakkouri, Majida; Chieh-Lin Lai, Christine; Pogoutse, Anastassia; Gray-Owen, Scott D.; Pomès, Régis; Moraes, Trevor F.

    2015-01-01

    Invading bacteria from the Neisseriaceae, Acinetobacteriaceae, Bordetellaceae and Moraxellaceae families express the conserved outer-membrane zinc transporter zinc-uptake component D (ZnuD) to overcome nutritional restriction imposed by the host organism during infection. Here we demonstrate that ZnuD is required for efficient systemic infections by the causative agent of bacterial meningitis, Neisseria meningitidis, in a mouse model. We also combine X-ray crystallography and molecular dynamics simulations to gain insight into the mechanism of zinc recognition and transport across the bacterial outer-membrane by ZnuD. Because ZnuD is also considered a promising vaccine candidate against N. meningitidis, we use several ZnuD structural intermediates to map potential antigenic epitopes, and propose a mechanism by which ZnuD can maintain high sequence conservation yet avoid immune recognition by altering the conformation of surface-exposed loops. PMID:26282243

  16. Lipopolysaccharide biogenesis and transport at the outer membrane of Gram-negative bacteria.

    Science.gov (United States)

    Sperandeo, Paola; Martorana, Alessandra M; Polissi, Alessandra

    2017-11-01

    The outer membrane (OM) of Gram-negative bacteria is an asymmetric lipid bilayer containing a unique glycolipid, lipopolysaccharide (LPS) in its outer leaflet. LPS molecules confer to the OM peculiar permeability barrier properties enabling Gram-negative bacteria to exclude many toxic compounds, including clinically useful antibiotics, and to survive harsh environments. Transport of LPS poses several problems to the cells due to the amphipatic nature of this molecule. In this review we summarize the current knowledge on the LPS transport machinery, discuss the challenges associated with this process and present the solutions that bacterial cells have evolved to address the problem of LPS transport and assembly at the cell surface. Finally, we discuss how knowledge on LPS biogenesis can be translated for the development of novel antimicrobial therapies. This article is part of a Special Issue entitled: Bacterial Lipids edited by Russell E. Bishop. Copyright © 2016. Published by Elsevier B.V.

  17. Outer Rail for Wall Plate Covering

    DEFF Research Database (Denmark)

    2013-01-01

    including an abutment part, which extends inwards from the inner side of the retention web such as to form an abutment surface for the respective screw web when the latter is positioned to be retained in the retention device, and extends from the abutment part into a locking part, which extends at an angle...... to the abutment part and at a distance from the respective retention web. Each locking part comprising a first resilient locking pin adapted to lock a first screw web configuration and a second, separate resilient locking pin adapted to lock a second screw web configuration, the first and second screw web...

  18. Insights into PG-binding, conformational change, and dimerization of the OmpA C-terminal domains from Salmonella enterica serovar Typhimurium and Borrelia burgdorferi: Characterization of OmpA C-Terminal Domain

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Kemin [Center for Structural Genomics of Infectious Diseases, University of Chicago, 5735 South Ellis Avenue Chicago Illinois 60637; Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne Illinois 60439; Deatherage Kaiser, Brooke L. [National Security Directorate, Pacific Northwest National Laboratory, Richland Washington 99352; Wu, Ruiying [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Cuff, Marianne [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Fan, Yao [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Bigelow, Lance [Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Jedrzejczak, Robert P. [Center for Structural Genomics of Infectious Diseases, University of Chicago, 5735 South Ellis Avenue Chicago Illinois 60637; Adkins, Joshua N. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland Washington 99352; Cort, John R. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland Washington 99352; Babnigg, Gyorgy [Center for Structural Genomics of Infectious Diseases, University of Chicago, 5735 South Ellis Avenue Chicago Illinois 60637; Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Joachimiak, Andrzej [Center for Structural Genomics of Infectious Diseases, University of Chicago, 5735 South Ellis Avenue Chicago Illinois 60637; Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Structural Biology Center, Biosciences, Argonne National Laboratory, Argonne Illinois 60439

    2017-06-19

    S. Typhimurium can induce both humoral and cell-mediated responses when establishing itself in the host. These responses are primarily stimulated against the lipopolysaccharide and major outer membrane (OM) proteins of the bacterium. OmpA is one of these major OM proteins. It comprises a N-terminal eight-stranded -barrel membrane domain and a C-terminal so-called OmpA C-terminal domain (OmpACTD). The OmpACTD and its homologs are believed to bind to peptidoglycan (PG) within the periplasm, maintaining bacterial osmotic homeostasis and modulating the permeability and integrity of the outer membrane. Here we present the structures of two forms of the OmpACTD of S. Typhimurium (STOmpACTD) and one structure of the less-studied OmpACTD of Borrelia burgdorferi (BbOmpACTD). In the open form of STOmpACTD, an aspartic acid residue from a long 2-3 loop points into the binding pocket, suggesting that an anion group such as a carboxylate group from PG is favored at the binding site. In the closed form of STOmpACTD and in the structure of BbOmpACTD, a sulfate group from the crystallization buffer is tightly bound at the equivalent site. The differences between the closed and open forms of STOmpACTD, suggest a large conformational change that includes an extension of 3 helix by ordering a part of 2-3 loop. We suggest that the sulfate anion observed in these structures mimics the carboxylate group of PG when bound to STOmpACTD. In addition, the binding of PG or a ligand mimic may enhance dimerization of STOmpACTD, or possibly that of full length STOmpA.

  19. Proposal for the LHCb outer tracker front-end electronics

    CERN Document Server

    Deppe, H; Feuerstack-Raible, M; Srowig, A; Stange, U; Hommels, B; Sluijk, T

    2001-01-01

    A market survey on available TDCs for reading out the LHCb Outer Tracker has left over only one TDC, which is not optimal for this purpose. Hence, a new readout architecture which is based on a TDC to be developed anew has been defined. This system fits optimal the requirements of the LHCb Outer Tracker and also should be much cheaper. The system and its main issues are described in this paper.

  20. Developments for the outer tracking system of the LHCb experiment

    CERN Document Server

    Bachmann, S; Haas, T; Uwer, U; Walter, M; Wiedner, D

    2004-01-01

    The outer tracking system of the LHCb experiment is discussed. The outer tracking system (OT) is made of three stations and every station is made up of four detecting planes with a double layer of straw tubes. The straw tubes are mounted in detector module boxes made up of sandwich panels. The use of a counting gas with a high drift velocity is suggested to cope with high bunch crossing rate at the LHCb experiment. (Edited abstract) 3 Refs.

  1. Inner and outer cylinders of the CMS vacuum tank.

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    The vacuum tank of the CMS magnet system consists of inner and outer stainless-steel cylinders and houses the superconducting coil. The inner cylinder contains all the barrel sub-detectors, which it supports via a system of horizontal rails. The cylinder is pictured here in the vertical position on a yellow platform mounted on the ferris-wheel support structure. This will allow it to be pivoted and inserted into the already installed outer cylinder, through which this photo was taken.

  2. Star laws: legal controls on armed conflict in outer space

    International Nuclear Information System (INIS)

    Stephens, Dale

    2016-01-01

    An undeclared military space race is unfolding yet there is no clear understanding of how international las operates in the field of armed conflict in outer space. In conjunction with McGill University Law School, Montreal, Canada, a 'Manual on international law applicable to military uses of outer space' has been drafted. This article looks at types of space weapons, previous space treaties and discusses humanitarian law.

  3. Development of CHF models for inner and outer RPV gaps in a meltdown severe accident

    International Nuclear Information System (INIS)

    Wang, J.; Tian, W.X.; Feng, K.; Yu, H.X.; Zhang, Y.P.; Su, G.H.; Qiu, S.Z.

    2013-01-01

    Highlights: • A CHF model was developed to predict the CHF in hemispherical narrow gap. • The computed result was validated by the test data of Park and Köhler. • An analytical CHF model was developed to predict the CHF on the outer surface of the lower head. • The predicted CHF was compared with the experimental data of ULPU-V. • Two CHF models developed for the inner and outer CHF predict the CHF well. - Abstract: During a severe accident, the core melt relocates in the lower head and a hemispherical narrow gap may appear between the crust and the lower head because of the different material expansion ratio. The existence of this gap is very important to the integrity of the lower head. Based on the counter current flow limitation (CCFL) between the vapor phase and the liquid phase, a CHF model was developed to predict the CHF in hemispherical narrow gap. The CHF model developed was validated by the test data of Park and Köhler. The effect of key parameters, including the system pressure, radius of melt, and gap size, on the CHF were investigated. And the TMI-2 accident was also calculated by using the CHF formula. Moreover, based on the interface separation model, an analytical CHF model was developed to predict the CHF on the outer surface of the lower head. The predicted CHF was compared with the experimental data of ULPU-V. It indicated that the CHF models developed for the inner and outer CHF could predict the CHF well

  4. THE OUTER MEMBRANE OF PATHOGENIC REPRESENTATIVES OF THE LEPTOSPIRA GENIUS

    Directory of Open Access Journals (Sweden)

    A. N. Vaganova

    2011-01-01

    Full Text Available Abstract. Pathogenic leptospires can infect wide spectrum of hosts and they can survive in the environment long time. The outer membrane is the cellular component participated in interaction of microorganisms and environment. In present time several proteins located in the outer membrane of leptospires which are responsible for colonization of host organism, protection from influence of immune system of host, transport of substances in to the cell and other processes have been described. The outer membrane contains proteins and lipopolysaccharide molecules which have citotoxic effect. It was shown that regulation of protein composition of membranes depends on several factors of environment such as temperature, osmolarity, presence of certain substances in environment. Lipopolysaccharide and protein molecules of outer membranes have antigenic properties. These molecules can be used in practice as the components of vaccine against leptospiroses and diagnostic tools. Current review summarize information concerning structural organization of the outer membrane of leptospires, diversities of incoming parts of molecules and regulation of their synthesis. Moreover, perspectives of practical using of the outer membrane components in diagnostics and prevention of leptospiroses are presented.

  5. Canine infection with Borrelia burgdorferi, Dirofilaria immitis, Anaplasma spp. and Ehrlichia spp. in Canada, 2013-2014.

    Science.gov (United States)

    Herrin, Brian H; Peregrine, Andrew S; Goring, Jonas; Beall, Melissa J; Little, Susan E

    2017-05-19

    Canine test results generated by veterinarians throughout Canada from 2013-2014 were evaluated to assess the geographical distribution of canine infection with Borrelia burgdorferi, Dirofilaria immitis, Ehrlichia spp., and Anaplasma spp. The percent positive test results of 115,636 SNAP® 4Dx® Plus tests from dogs tested were collated by province and municipality to determine the distribution of these vector-borne infections in Canada. A total of 2,844/115,636 (2.5%) dogs tested positive for antibody to B. burgdorferi. In contrast, positive test results for D. immitis antigen and antibodies to Ehrlichia spp. and Anaplasma spp. were low, with less than 0.5% of dogs testing positive for any one of these three agents nationwide. Provincial seroprevalence for antibodies to B. burgdorferi ranged from 0.5% (Saskatchewan)-15.7% (Nova Scotia); the areas of highest percent positive test results were in proximity to regions in the USA considered endemic for Lyme borreliosis, including Nova Scotia (15.7%) and Eastern Ontario (5.1%). These high endemic foci, which had significantly higher percent positive test results than the rest of the nation (P Canada. Using dogs as sentinels for these pathogens can aid in recognition of the public and veterinary health threat that each pose.

  6. Polysynovitis in a horse due to [i]Borrelia burgdorferi[/i] sensu lato infection – Case study

    Directory of Open Access Journals (Sweden)

    Fabrizio Passamonti

    2015-05-01

    Full Text Available Lyme borreliosis (LB is a multi-systemic tick-borne disease affecting both humans and animals, including horses, and is caused by a group of interrelated spirochetes classified within the[i] Borrelia burgdorferi [/i]sensu lato (s.l. complex. Despite the high reported seroprevalence in the European equine population for [i]B. burgdorferi[/i] s.l., to-date no documented clinical cases have been described. A 6-year-old Paint gelding was referred with a history of three weeks of fever, intermittent lameness and digital flexor tendon sheath effusion of the right hind limb. Based on a strict diagnostic protocol, which included serological tests for infectious diseases and molecular investigations, a final diagnosis was made of polysynovitis due to [i]B. burgdorferi [/i]s.l. infection. An unreported aspect observed in this case was the absence of the pathogen DNA in two of the affected joints. To the authors’ knowledge, the case described represents the first documented clinical case of equine LB in Italy. Moreover, the absence of pathogen DNA in two of the affected joints observed in this case revealed a possible similarity with the same condition described in humans, where an immunomediated pathogenesis for arthropathy due to [i]B. burgdorferi[/i] s.l. infection is suspected. Since humans and horses share the same habitat, this report supports the role of the horse as potential sentinel for human biological risk.

  7. Leptospira spp. vaccinal antibodies do not react with Borrelia burgdorferi peptides used in the AccuPlex 4.

    Science.gov (United States)

    Caress, Amber L; Moroff, Scott; Lappin, Michael R

    2017-11-01

    We attempted to determine if Leptospira spp. antibodies induced by vaccination would cross-react with Borrelia burgdorferi antigens used in a commercial automated immunofluorescent assay (AccuPlex 4 BioCD; Antech). Staff- and student-owned dogs ( n = 31) were recruited at a veterinary teaching hospital in a B. burgdorferi nonendemic area. The dogs were randomized and administered 1 of 4 commercial Leptospira spp. vaccines that contained serovars Canicola, Grippotyphosa, Icterohaemorrhagiae, and Pomona, then booster vaccinated 3 wk later. Blood was collected on weeks 0, 3, 4, 8, and 12. After confirming that maximal Leptospira spp. titers occurred on week 4, aliquots of sera from week 4 were shipped frozen for analysis of B. burgdorferi antibodies against OspA, OspC, OspF, P39, and SLP with the AccuPlex system. Week 4 sera from all 31 dogs had a titer of 1:100 for at least 1 Leptospira spp. serovar. Titers of 1:800 or greater were detected against multiple serovars in 27 dogs. None of the samples contained antibodies against the B. burgdorferi OspA, OspC, OspF, P39, and SLP peptides used in the commercial assay. The B. burgdorferi peptides used in the AccuPlex system do not recognize naturally occurring Leptospira spp. antibodies or those induced by the commercial Leptospira spp. vaccines administered in our study.

  8. Minimal role of eastern fence lizards in Borrelia burgdorferi transmission in central New Jersey oak/pine woodlands

    Science.gov (United States)

    Rulison, Eric L.; Kerr, Kaetlyn T; Dyer, Megan C; Han, Seungeun; Burke, Russell L.; Tsao, Jean I.; Ginsberg, Howard S.

    2014-01-01

    The Eastern fence lizard, Sceloporus undulatus, is widely distributed in eastern and central North America, ranging through areas with high levels of Lyme disease, as well as areas where Lyme disease is rare or absent. We studied the potential role of S. undulatus in transmission dynamics of Lyme spirochetes by sampling ticks from a variety of natural hosts at field sites in central New Jersey, and by testing the reservoir competence of S. undulatus for Borrelia burgdorferi in the laboratory. The infestation rate of ticks on fence lizards was extremely low (proportion infested = 0.087, n = 23) compared to that on white footed mice and other small mammals (proportion infested = 0.53, n = 140). Of 159 nymphs that had fed as larvae on lizards that had previously been exposed to infected nymphs, none was infected with B. burgdorferi, compared with 79.9% of 209 nymphs that had fed as larvae on infected control mice. Simulations suggest that changes in the numbers of fence lizards in a natural habitat would have little effect on the infection rate of nymphal ticks with Lyme spirochetes. We conclude that in central New Jersey S. undulatus plays a minimal role in the enzootic transmission cycle of Lyme spirochetes.

  9. Managing Japanese barberry (Ranunculales: Berberidaceae) infestations reduces blacklegged tick (Acari: Ixodidae) abundance and infection prevalence with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae).

    Science.gov (United States)

    Williams, Scott C; Ward, Jeffrey S; Worthley, Thomas E; Stafford, Kirby C

    2009-08-01

    In many Connecticut forests with an overabundance of white-tailed deer (Odocoileus virginianus Zimmermann), Japanese barberry (Berberis thunbergii DC) has become the dominant understory shrub, which may provide a habitat favorable to blacklegged tick (Ixodes scapularis Say) and white-footed mouse (Peromyscus leucopus Rafinesque) survival. To determine mouse and larval tick abundances at three replicate sites over 2 yr, mice were trapped in unmanipulated dense barberry infestations, areas where barberry was controlled, and areas where barberry was absent. The number of feeding larval ticks/mouse was recorded. Adult and nymphal ticks were sampled along 200-m draglines in each treatment, retained, and were tested for Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner) presence. Total first-captured mouse counts did not differ between treatments. Mean number of feeding larval ticks per mouse was highest on mice captured in dense barberry. Adult tick densities in dense barberry were higher than in both controlled barberry and no barberry areas. Ticks sampled from full barberry infestations and controlled barberry areas had similar infection prevalence with B. burgdorferi the first year. In areas where barberry was controlled, infection prevalence was reduced to equal that of no barberry areas the second year of the study. Results indicate that managing Japanese barberry will have a positive effect on public health by reducing the number of B. burgdorferi-infected blacklegged ticks that can develop into motile life stages that commonly feed on humans.

  10. Borrelia burgdorferi in small mammal reservoirs in Kentucky, a traditionally non-endemic state for Lyme disease.

    Science.gov (United States)

    Buchholz, Matthew J; Davis, Cheryl; Rowland, Naomi S; Dick, Carl W

    2018-04-01

    The incidence of tick-borne zoonoses such as Lyme disease has steadily increased in the southeastern United States. Southeastern states accounted for 1500 of over 28,000 confirmed cases of Lyme disease reported in the United States during 2015. Borrelia burgdorferi, the etiologic agent of Lyme disease, is maintained in small mammal reservoirs and vectored to new hosts by ixodid ticks. This study examined ecological relationships of the B. burgdorferi/vector/reservoir system in order to understand the dynamics of Lyme disease risk in Kentucky. Small mammals were captured using live traps from November 2014 to October 2015. Ticks were removed and blood and tissue collected from small mammals were screened for B. burgdorferi DNA by PCR with primers specific to the OspA gene. Prevalence of B. burgdorferi (21.8%) in Kentucky small mammals was comparable to the lowest recorded prevalence in regions where Lyme disease is endemic. Moreover, infestation of small mammals by Ixodes scapularis, the primary vector of B. burgdorferi, was rare, while Dermacentor variabilis comprised the majority of ticks collected. These findings provide ecological insight into the relative paucity of Lyme disease in Kentucky.

  11. Comprehensive surveillance of the antibody response to Borrelia burgdorferi s.l. in small ruminants in China

    Directory of Open Access Journals (Sweden)

    Jifei Yang

    2015-05-01

    Full Text Available Borrelia burgdorferi sensu lato, the etiological agent of Lyme disease, is tick transmitted and has a wide range of mammalian reservoirs in nature, including both wild and domestic animals. To understand the seroprevalence of B. burgdorferi s.l. in small ruminants will add value to the risk analysis of Lyme disease. The current study was intended to map the potential endemic regions of Lyme disease by large-scale investigation of sera from sheep and goats. In this study, a total of 2,758 serum samples from sheep and goats in 21 provinces located in 40 different districts of China were tested for antibodies against B. burgdorferi s.l. by enzyme-linked immunosorbent assay. The results of this survey indicated that the overall prevalence of B. burgdorferi s.l. infection ranges from 5.3 to 63.5 % (mean: 26.3%, and the infection was found in all provinces investigated. Generally, the positive rate declined from the south (34.7% in south and 32.4% in southwest towards the north of China (18.4% in north, 16.5% in northeast and 17.2% in northwest. A significant difference was also observed in the infection rate between south and north (33.2% versus 17.4%, PB. burgdorferi s.l. in small ruminants in China.

  12. Detailed Structure of the Outer Disk Around HD 169142 with Polarized Light in H-band

    Science.gov (United States)

    Momose, Munetake; Morita, Ayaka; Fukagawa, Misato; Muto, Takayuki; Takeuchi, Taku; Hashimoto, Jun; Honda, Mitsuhiko; Kudo, Tomoyuki; Okamoto, Yoshiko K.; Kanagawa, Kazuhiro D.; hide

    2015-01-01

    Coronagraphic imagery of the circumstellar disk around HD 169142 in H-band polarized intensity (PI) with Subaru/HiCIAO is presented. The emission scattered by dust particles at the disk surface in 0.''2=r=1.''2, or 29=r=174 AU, is successfully detected. The azimuthally-averaged radial profile of the PI shows a double power-law distribution, in which the PIs in r = 29-52 AU and r = 81.2-145 AU respectively show r-3-dependence. These two power-law regions are connected smoothly with a transition zone (TZ), exhibiting an apparent gap in r = 40-70 AU. The PI in the inner power-law region shows a deep minimum whose location seems to coincide with the point source at lambda = 7 mm. This can be regarded as another sign of a protoplanet in TZ. The observed radial profile of the PI is reproduced by a minimally flaring disk with an irregular surface density distribution or with an irregular temperature distribution or with the combination of both. The depletion factor of surface density in the inner power-law region (r <50 AU) is derived to be =0.16 from a simple model calculation. The obtained PI image also shows small scale asymmetries in the outer power-law region. Possible origins for these asymmetries include corrugation of the scattering surface in the outer region, and shadowing effect by a puffed up structure in the inner power-law region.

  13. Building a flagellum in biological outer space

    Directory of Open Access Journals (Sweden)

    Lewis D. B. Evans

    2014-01-01

    Full Text Available Flagella, the rotary propellers on the surface of bacteria, present a paradigm for how cells build and operate complex molecular ‘nanomachines’. Flagella grow at a constant rate to extend several times the length of the cell, and this is achieved by thousands of secreted structural subunits transiting through a central channel in the lengthening flagellum to incorporate into the nascent structure at the distant extending tip. A great mystery has been how flagella can assemble far outside the cell where there is no conventional energy supply to fuel their growth. Recent work published by Evans et al.[Nature (2013 504: 287-290], has gone some way towards solving this puzzle, presenting a simple and elegant transit mechanism in which growth is powered by the subunits themselves as they link head-to-tail in a chain that is pulled through the length of the growing structure to the tip. This new mechanism answers an old question and may have resonance in other assembly processes.

  14. Formation of the outer layer of the Dictyostelium spore coat depends on the inner-layer protein SP85/PsB.

    Science.gov (United States)

    Metcalf, Talibah; Kelley, Karen; Erdos, Gregory W; Kaplan, Lee; West, Christopher M

    2003-02-01

    The Dictyostelium spore is surrounded by a 220 microm thick trilaminar coat that consists of inner and outer electron-dense layers surrounding a central region of cellulose microfibrils. In previous studies, a mutant strain (TL56) lacking three proteins associated with the outer layer exhibited increased permeability to macromolecular tracers, suggesting that this layer contributes to the coat permeability barrier. Electron microscopy now shows that the outer layer is incomplete in the coats of this mutant and consists of a residual regular array of punctate electron densities. The outer layer is also incomplete in a mutant lacking a cellulose-binding protein associated with the inner layer, and these coats are deficient in an outer-layer protein and another coat protein. To examine the mechanism by which this inner-layer protein, SP85, contributes to outer-layer formation, various domain fragments were overexpressed in forming spores. Most of these exert dominant negative effects similar to the deletion of outer-layer proteins, but one construct, consisting of a fusion of the N-terminal and Cys-rich C1 domain, induces a dense mat of novel filaments at the surface of the outer layer. Biochemical studies show that the C1 domain binds cellulose, and a combination of site-directed mutations that inhibits its cellulose-binding activity suppresses outer-layer filament induction. The results suggest that, in addition to a previously described early role in regulating cellulose synthesis, SP85 subsequently contributes a cross-bridging function between cellulose and other coat proteins to organize previously unrecognized structural elements in the outer layer of the coat.

  15. A Peptidomimetic Antibiotic Targets Outer Membrane Proteins and Disrupts Selectively the Outer Membrane in Escherichia coli.

    Science.gov (United States)

    Urfer, Matthias; Bogdanovic, Jasmina; Lo Monte, Fabio; Moehle, Kerstin; Zerbe, Katja; Omasits, Ulrich; Ahrens, Christian H; Pessi, Gabriella; Eberl, Leo; Robinson, John A

    2016-01-22

    Increasing antibacterial resistance presents a major challenge in antibiotic discovery. One attractive target in Gram-negative bacteria is the unique asymmetric outer membrane (OM), which acts as a permeability barrier that protects the cell from external stresses, such as the presence of antibiotics. We describe a novel β-hairpin macrocyclic peptide JB-95 with potent antimicrobial activity against Escherichia coli. This peptide exhibits no cellular lytic activity, but electron microscopy and fluorescence studies reveal an ability to selectively disrupt the OM but not the inner membrane of E. coli. The selective targeting of the OM probably occurs through interactions of JB-95 with selected β-barrel OM proteins, including BamA and LptD as shown by photolabeling experiments. Membrane proteomic studies reveal rapid depletion of many β-barrel OM proteins from JB-95-treated E. coli, consistent with induction of a membrane stress response and/or direct inhibition of the Bam folding machine. The results suggest that lethal disruption of the OM by JB-95 occurs through a novel mechanism of action at key interaction sites within clusters of β-barrel proteins in the OM. These findings open new avenues for developing antibiotics that specifically target β-barrel proteins and the integrity of the Gram-negative OM. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Linear stability of resistive MHD modes: axisymmetric toroidal computation of the outer region matching data

    International Nuclear Information System (INIS)

    Pletzer, A.; Bondeson, A.; Dewar, R.L.

    1993-11-01

    The quest to determine accurately the stability of tearing and resistive interchange modes in two-dimensional toroidal geometry led to the development of the PEST-3 code, which is based on solving the singular, zero-frequency ideal MHD equation in the plasma bulk and determining the outer data Δ', Γ' and A' needed to match the outer region solutions to those arising in the inner layers. No assumption regarding the aspect ratio, the number of rational surfaces or the pressure are made a priori. This approach is numerically less demanding than solving the full set of resistive equations, and has the major advantage of non-MHD theories of the non-ideal layers. Good convergence is ensured by the variational Galerkin scheme used to compute the outer matching data. To validate the code, we focus on the growth rate calculations of resistive kink modes which are reproduced in good agreement with those obtained by the full resistive MHD code MARS. (author) 11 figs., 27 refs

  17. The mitochondrial outer membrane protein MDI promotes local protein synthesis and mtDNA replication.

    Science.gov (United States)

    Zhang, Yi; Chen, Yong; Gucek, Marjan; Xu, Hong

    2016-05-17

    Early embryonic development features rapid nuclear DNA replication cycles, but lacks mtDNA replication. To meet the high-energy demands of embryogenesis, mature oocytes are furnished with vast amounts of mitochondria and mtDNA However, the cellular machinery driving massive mtDNA replication in ovaries remains unknown. Here, we describe a Drosophila AKAP protein, MDI that recruits a translation stimulator, La-related protein (Larp), to the mitochondrial outer membrane in ovaries. The MDI-Larp complex promotes the synthesis of a subset of nuclear-encoded mitochondrial proteins by cytosolic ribosomes on the mitochondrial surface. MDI-Larp's targets include mtDNA replication factors, mitochondrial ribosomal proteins, and electron-transport chain subunits. Lack of MDI abolishes mtDNA replication in ovaries, which leads to mtDNA deficiency in mature eggs. Targeting Larp to the mitochondrial outer membrane independently of MDI restores local protein synthesis and rescues the phenotypes of mdi mutant flies. Our work suggests that a selective translational boost by the MDI-Larp complex on the outer mitochondrial membrane might be essential for mtDNA replication and mitochondrial biogenesis during oogenesis. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  18. Green Modification of Outer Selective P84 Nanofiltration (NF) Hollow Fiber Membranes for Cadmium Removal

    KAUST Repository

    Gao, Jie

    2015-10-26

    Outer-selective thin-film composite (TFC) hollow fiber membranes are normally made from interfacial polymerization of m-phenylenediamine (MPD) and trimesoyl chloride (TMC). However, the removal of excess MPD solution and the large consumption of alkane solvents are their technical bottlenecks. In this study, green methods to prepare the outer selective TFC hollow fiber membranes were explored by firstly modifying the membrane substrate with polyethyleneimine (PEI) and then by water soluble small molecules such as glutaraldehyde (GA) and epichlorohydrin (ECH). Using P84 polyimide as the substrate, not only do these modifications decrease substrate\\'s pore size, but also vary surface charge by making the membranes less positively charged. As a result, the resultant membranes have higher rejections against salts such as Na2SO4, NaCl and MgSO4. The PEI and then GA modified membrane has the best separation performance with a NaCl rejection over 90% and a pure water permeability (PWP) of 1.74±0.01 Lm−2bar−1h−1. It also shows an impressive rejection to CdCl2 (94%) during long-term stability tests. The CdCl2 rejection remains higher than 90% at operating temperatures from 5 to 60 °C. This study may provide useful insights for green manufacturing of outer-selective nanofiltration (NF) hollow fiber membranes.

  19. The Effects of Urethane on Rat Outer Hair Cells

    Directory of Open Access Journals (Sweden)

    Mingyu Fu

    2016-01-01

    Full Text Available The cochlea converts sound vibration into electrical impulses and amplifies the low-level sound signal. Urethane, a widely used anesthetic in animal research, has been shown to reduce the neural responses to auditory stimuli. However, the effects of urethane on cochlea, especially on the function of outer hair cells, remain largely unknown. In the present study, we compared the cochlear microphonic responses between awake and urethane-anesthetized rats. The results revealed that the amplitude of the cochlear microphonic was decreased by urethane, resulting in an increase in the threshold at all of the sound frequencies examined. To deduce the possible mechanism underlying the urethane-induced decrease in cochlear sensitivity, we examined the electrical response properties of isolated outer hair cells using whole-cell patch-clamp recording. We found that urethane hyperpolarizes the outer hair cell membrane potential in a dose-dependent manner and elicits larger outward current. This urethane-induced outward current was blocked by strychnine, an antagonist of the α9 subunit of the nicotinic acetylcholine receptor. Meanwhile, the function of the outer hair cell motor protein, prestin, was not affected. These results suggest that urethane anesthesia is expected to decrease the responses of outer hair cells, whereas the frequency selectivity of cochlea remains unchanged.

  20. Software alignment of the LHCb Outer Tracker chambers

    Energy Technology Data Exchange (ETDEWEB)

    Deissenroth, Marc

    2010-04-21

    This work presents an alignment algorithm that was developed to precisely determine the positions of the LHCb Outer Tracker detector elements. The algorithm is based on the reconstruction of tracks and exploits that misalignments of the detector change the residual between a measured hit and the reconstructed track. It considers different levels of granularities of the Outer Tracker geometry and fully accounts for correlations of all elements which are imposed by particle trajectories. In extensive tests, simulated shifts and rotations for different levels of the detector granularity have been used as input to the track reconstruction and alignment procedure. With about 260 000 tracks the misalignments are recovered with a statistical precision of O(10 - 100 {mu}m) for the translational degrees of freedom and of O(10{sup -2} - 10{sup -1} mrad) for rotations. A study has been performed to determine the impact of Outer Tracker misalignments on the performance of the track reconstruction algorithms. It shows that the achieved statistical precision does not decrease the track reconstruction performance in a significant way. During the commissioning of the LHCb detector, cosmic ray muon events have been collected. The events have been analysed and used for the first alignment of the 216 Outer Tracker modules. The module positions have been determined within {proportional_to} 90 {mu}m. The developed track based alignment algorithm has demonstrated its reliability and is one of the core algorithms which are used for the precise determination of the positions of the LHCb Outer Tracker elements. (orig.)

  1. AN OUTER ARM IN THE SECOND GALACTIC QUADRANT: STRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Du, Xinyu; Xu, Ye; Yang, Ji; Sun, Yan; Li, Facheng; Zhang, Shaobo; Zhou, Xin, E-mail: xydu@pmo.ac.cn, E-mail: xuye@pmo.ac.cn [Purple Mountain Observatory, Chinese Academy of Science, Nanjing 210008 (China)

    2016-05-01

    The lack of arm tracers, especially remote tracers, is one of the most difficult problems preventing us from studying the structure of the Milky Way. Fortunately, with its high-sensitivity CO survey, the Milky Way Imaging Scroll Painting (MWISP) project offers such an opportunity. Since completing about one-third of its mission, an area of l = [100, 150]°, b = [−3, 5]° has nearly been covered. The Outer arm of the Milky Way first clearly revealed its shape in the second galactic quadrant in the form of molecular gas—this is the first time that the Outer arm has been reported in such a large-scale mapping of molecular gas. Using the 115 GHz {sup 12}CO(1–0) data of MWISP at the LSR velocity ≃[−100, −60] km s{sup −1} and in the area mentioned above, we have detected 481 molecular clouds in total, and among them 332 (about 69%) are newly detected and 457 probably belong to the Outer arm. The total mass of the detected Outer arm clouds is ∼3.1 × 10{sup 6} M {sub ⊙}. Assuming that the spiral arm is a logarithmic spiral, the pitch angle is fitted as ∼13.°1. Besides combining both the CO data from MWISP and the 21 cm H i data from the Canadian Galactic Plane Survey (CGPS), the gas distribution, warp, and thickness of the Outer arm are also studied.

  2. Software alignment of the LHCb Outer Tracker chambers

    International Nuclear Information System (INIS)

    Deissenroth, Marc

    2010-01-01

    This work presents an alignment algorithm that was developed to precisely determine the positions of the LHCb Outer Tracker detector elements. The algorithm is based on the reconstruction of tracks and exploits that misalignments of the detector change the residual between a measured hit and the reconstructed track. It considers different levels of granularities of the Outer Tracker geometry and fully accounts for correlations of all elements which are imposed by particle trajectories. In extensive tests, simulated shifts and rotations for different levels of the detector granularity have been used as input to the track reconstruction and alignment procedure. With about 260 000 tracks the misalignments are recovered with a statistical precision of O(10 - 100 μm) for the translational degrees of freedom and of O(10 -2 - 10 -1 mrad) for rotations. A study has been performed to determine the impact of Outer Tracker misalignments on the performance of the track reconstruction algorithms. It shows that the achieved statistical precision does not decrease the track reconstruction performance in a significant way. During the commissioning of the LHCb detector, cosmic ray muon events have been collected. The events have been analysed and used for the first alignment of the 216 Outer Tracker modules. The module positions have been determined within ∝ 90 μm. The developed track based alignment algorithm has demonstrated its reliability and is one of the core algorithms which are used for the precise determination of the positions of the LHCb Outer Tracker elements. (orig.)

  3. Pleomorphism and Viability of the Lyme Disease Pathogen Borrelia burgdorferi Exposed to Physiological Stress Conditions: A Correlative Cryo-Fluorescence and Cryo-Scanning Electron Microscopy Study

    Czech Academy of Sciences Publication Activity Database

    Vancová, Marie; Rudenko, Natalia; Vaněček, Jiří; Golovchenko, Maryna; Strnad, Martin; Rego, Ryan O. M.; Tichá, Lucie; Grubhoffer, Libor; Nebesářová, Jana

    2017-01-01

    Roč. 8, 11 April (2017), č. článku 596. ISSN 1664-302X R&D Projects: GA TA ČR(CZ) TE01020118; GA MŠk(CZ) LM2015062 EU Projects: European Commission(XE) 278976 - ANTIGONE Institutional support: RVO:60077344 Keywords : cryo-fluorescence * cryo-scanning electron microscopy * Borrelia burgdorferi * Lyme disease * round body * pleomorphism * viability staining Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: 2.11 Other engineering and technologies Impact factor: 4.076, year: 2016

  4. Prevalence of Borrelia burgdorferi in ticks removed from skin of people and circumstances of being bitten - research from the area of Poland, 2012-2014.

    Science.gov (United States)

    Gałęziowska, Edyta; Rzymowska, Jolanta; Najda, Nella; Kołodziej, Przemysław; Domżał-Drzewicka, Renata; Rząca, Marcin; Muraczyńska, Bożena; Charzyńska-Gula, Marianna; Szadowska-Szlachetka, Zdzisława; Ślusarska, Barbara; Guty, Edyta

    2018-03-14

    During feeding, the tick sucks blood from the host along with the pathogens that are in the blood, simultaneously exchanging its own pathogens with the host. Humans can also be a host. It is important to understand the most typical circumstances in which people might become infected with Borrelia burgdorferi. This knowledge will help to prepare health education programmes aimed at the prevention of Lyme disease and other tick-borne diseases. The aim of the study was to determine the percentage of ticks infected with Borrelia burgdorferi sensu lato, depending on the circumstances of getting bitten. The research material consisted of ticks acquired from people who had been bitten, and questionnaires completed by these people. 510 ticks were acquired from 257 females and 253 males. Following delivery of a tick for testing, the stage of its development was determined and a molecular assay of Borrelia burgdorferi DNA performed. A positive result of the nested-PCR test was obtained in 78 ticks, which represents 15.30% of all ticks. The infected ticks were collected from male (41 ticks - 52.56%) and female subjects (37 ticks - 47.44%). The biggest number of infected ticks were collected in autumn (54 ticks - 69.23%) and from people who had been into forests (44 ticks - 56.41%). Among the people from whom the infected ticks were acquired, the dominating group included persons over 16 years of age (53 persons - 67.95%) and children aged 0-5 years (16 persons - 20.51%). One in four infected ticks were acquired from the southwestern (20 ticks - 25.64%) and eastern regions of Poland (21 ticks - 26.92%). Infestation of ticks infected with Lyme disease spirochete in this study proved to be variable and depend on the season, the area of tick attack and the region in Poland. The results of the study clearly show that ticks infected with Borrelia burgdorferi inhabit all regions of Poland. The results are consistent with National Institute of Hygiene data which indicates that Lyme

  5. Detection of Borrelia lusitaniae, Rickettsia sp. IRS3, Rickettsia monacensis, and Anaplasma phagocytophilum in Ixodes ricinus collected in Madeira Island, Portugal.

    Science.gov (United States)

    de Carvalho, Isabel Lopes; Milhano, Natacha; Santos, Ana Sofia; Almeida, Victor; Barros, Silvia C; De Sousa, Rita; Núncio, Maria Sofia

    2008-08-01

    A total of 300 Ixodes ricinus ticks were tested by polymerase chain reaction (PCR) for the presence of Borrelia spp., Rickettsia spp., and Anaplasma phagocytophilum. Sequence analysis demonstrated 8 (2.7%) ticks infected with B. lusitaniae, 60 (20%) with Rickettsia spp., and 1 (0.3%) with A. phagocytophilum. Seven (2.3%) ticks were coinfected with B. lusitaniae and Rickettsia spp., 2 (0.6%) with R. monacensis, and 5 (1.7%) with Rickettsia sp. IRS3. The results of this study suggest simultaneous transmission of multiple tick-borne agents on Madeira Island, Portugal.

  6. Exposure to ticks and seroprevalence of [i]Borrelia burgdorferi [/i]among a healthy young population living in the area of southern Podlasie, Poland

    Directory of Open Access Journals (Sweden)

    Anna Pańczuk

    2014-09-01

    Full Text Available [b]Objectives[/b]. The objective of the study was assessment of risk of infection with [i]Borrelia burgdorferi[/i] in the area of southern Podlasie in Poland, near the border with Belarus, by analysis of post-exposure procedure, and evaluation of asymptomatic infection in adolescents bitten by a tick, confirmed by serologic tests. [b]Material and methods[/b]. The study was conducted among 128 healthy individuals aged 16–20 who declared being bitten by a tick. The level of IgM and IgG class antibodies was determined using the immunoenzymatic test (Borrelia 14 kD + OspC IgM ELISA and Borrelia IgG + VlsE ELISA, DRG Diagnostics. Positive and doubtful results were confirmed using the Western blot method (EUROLINE-WB, EUROIMMUN. [b]Results[/b]. In the study group, the largest number of respondents (59.4% declared tick bite in the region of the lower extremities, most often in the knee pit. Among the methods for removing the tick the largest number of respondents indicated removing it with the use of tweezers, with a simple, swift steady movement (29.7%, and pulling it out with the fingers (22.7%. In the ELISA test, a positive or doubtful result in at least one class was observed in 25.0% of respondents (n=32/128: in IgM class – 23.4% (n=30/128, and in IgG class – 4.7% (n=6/128. After verification with the Western blot test, infection was confirmed in 5.5% of respondents (n=7/128: in IgM class – 1.6% (n=2/128, in IgG class – 3.9% (n=5/128. In IgM class antibodies, the Western blot test confirmed positive or doubtful results of the ELISA test in 6.7%, while in IgG class antibodies in 83.3%. [b]Conclusion[/b]. Evaluation of the actual infection with [i]Borrelia spp.[/i] using serologic tests is difficult due to a certain non-specificity of the ELISA test, especially in IgM class antibodies, and difficulties with performance of a wide scope of specific Western blot tests. The variety of methods of tick removal declared by adolescents suggests

  7. Solar System Exploration Augmented by Lunar and Outer Planet Resource Utilization: Historical Perspectives and Future Possibilities

    Science.gov (United States)

    Palaszewski, Bryan

    2014-01-01

    Establishing a lunar presence and creating an industrial capability on the Moon may lead to important new discoveries for all of human kind. Historical studies of lunar exploration, in-situ resource utilization (ISRU) and industrialization all point to the vast resources on the Moon and its links to future human and robotic exploration. In the historical work, a broad range of technological innovations are described and analyzed. These studies depict program planning for future human missions throughout the solar system, lunar launched nuclear rockets, and future human settlements on the Moon, respectively. Updated analyses based on the visions presented are presented. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal propulsion, nuclear surface power, as well as advanced chemical propulsion can significantly enhance these scenarios. Robotic and human outer planet exploration options are described in many detailed and extensive studies. Nuclear propulsion options for fast trips to the outer planets are discussed. To refuel such vehicles, atmospheric mining in the outer solar system has also been investigated as a means of fuel production for high energy propulsion and power. Fusion fuels such as helium 3 (3He) and hydrogen (H2) can be wrested from the atmospheres of Uranus and Neptune and either returned to Earth or used in-situ for energy production. Helium 3 and H2 (deuterium, etc.) were the primary gases of interest with hydrogen being the primary propellant for nuclear thermal solid core and gas core rocket-based atmospheric flight. A series of analyses have investigated resource capturing aspects of atmospheric mining in the outer solar system. These analyses included the gas capturing rate, storage options, and different methods of direct use of the captured gases. While capturing 3He, large amounts of hydrogen and 4He are produced. With these two additional

  8. Analyses of a steel containment vessel with an outer contact structure under severe internal overpressurization conditions

    International Nuclear Information System (INIS)

    Porter, V.L.

    1994-01-01

    Many Mark-I and Mark-II BWR plants are designed with a steel vessel as the primary containment. Typically, the steel containment vessel (SCV) is enclosed within a reinforced concrete shield building with only a small gap (74-90 mm) separating the two structures. This paper describes finite element analyses performed to evaluate the effects of contact and friction between a steel containment vessel and an outer contact structure when the containment vessel is subjected to large internal pressures. These computations were motivated by a joint program on containment integrity involving the Nuclear Power Engineering Corporation (NUPEC) of Japan, the US Nuclear Regulatory Commission (NRC), and Sandia National Laboratories for testing model containments. Under severe accident loading conditions, the steel containment vessel in a typical Mark-I or Mark-II plant may deform under internal pressurization such that it contacts the inner surface of a shield building wall. (Thermal expansion from increasing accident temperatures would also close the gap between the SCV and the shield building, but temperature effects are not considered in these analyses.) The amount and location of contact and the pressure at which it occurs all affect how the combined structure behaves. A preliminary finite element model has been developed to analyze a model of a typical steel containment vessel con-ling into contact with an outer structure. Both the steel containment vessel and the outer contact structure were modelled with axisymmetric shell finite elements. Of particular interest are the influence that the contact structure has on deformation and potential failure modes of the containment vessel. Furthermore, the coefficient of friction between the two structures was varied to study its effects on the behavior of the containment vessel and on the uplift loads transmitted to the contact structure. These analyses show that the material properties of an outer contact structure and the amount

  9. Substrate specificity within a family of outer membrane carboxylate channels.

    Directory of Open Access Journals (Sweden)

    Elif Eren

    2012-01-01

    Full Text Available Many Gram-negative bacteria, including human pathogens such as Pseudomonas aeruginosa, do not have large-channel porins. This results in an outer membrane (OM that is highly impermeable to small polar molecules, making the bacteria intrinsically resistant towards many antibiotics. In such microorganisms, the majority of small molecules are taken up by members of the OprD outer membrane protein family. Here we show that OprD channels require a carboxyl group in the substrate for efficient transport, and based on this we have renamed the family Occ, for outer membrane carboxylate channels. We further show that Occ channels can be divided into two subfamilies, based on their very different substrate specificities. Our results rationalize how certain bacteria can efficiently take up a variety of substrates under nutrient-poor conditions without compromising membrane permeability. In addition, they explain how channel inactivation in response to antibiotics can cause resistance but does not lead to decreased fitness.

  10. Knitted outer gloves in primary hip and knee arthroplasty.

    Science.gov (United States)

    Tanner, J; Wraighte, P; Howard, P

    2006-01-01

    A randomised trial was carried out to determine the rate of perforation to inner gloves when comparing latex with knitted gloves during hip and knee arthroplasty. Members of the surgical team were randomised to wear either two pairs of latex gloves (standard double gloving) or a knitted glove on top of a latex glove. In addition, participants completed a visual analogue assessment of their overall satisfaction with the gloves. A total of 406 inner gloves were tested for perforations over a four-month period: 23% of inner gloves were perforated when latex outer gloves were used and 6% of inner gloves were perforated when knitted outer gloves were used. In total, there were 64 perforations to the inner gloves; only one of these perforations was detected by the glove wearer. Wearing knitted outer gloves during hip and knee arthroplasty statistically significantly reduces the risk of perforation to inner latex gloves (p<0.0001).

  11. Outer Planet Missions with Electric Propulsion Systems—Part I

    Directory of Open Access Journals (Sweden)

    Carlos Renato Huaura Solórzano

    2010-01-01

    Full Text Available For interplanetary missions, efficient electric propulsion systems can be used to increase the mass delivered to the destination. Outer planet exploration has experienced new interest with the launch of the Cassini and New Horizons Missions. At the present, new technologies are studied for better use of electric propulsion systems in missions to the outer planets. This paper presents low-thrust trajectories using the method of the transporting trajectory to Uranus, Neptune, and Pluto. They use nuclear and radio isotopic electric propulsion. These direct transfers have continuous electric propulsion of low power along the entire trajectory. The main goal of the paper is to optimize the transfers, that is, to provide maximum mass to be delivered to the outer planets.

  12. The outer magnetosphere. [composition and comparison with earth

    Science.gov (United States)

    Schardt, A. W.; Behannon, K. W.; Lepping, R. P.; Carbary, J. F.; Eviatar, A.; Siscoe, G. L.

    1984-01-01

    Similarities between the Saturnian and terrestrial outer magnetosphere are examined. Saturn, like earth, has a fully developed magnetic tail, 80 to 100 RS in diameter. One major difference between the two outer magnetospheres is the hydrogen and nitrogen torus produced by Titan. This plasma is, in general, convected in the corotation direction at nearly the rigid corotation speed. Energies of magnetospheric particles extend to above 500 keV. In contrast, interplanetary protons and ions above 2 MeV have free access to the outer magnetosphere to distances well below the Stormer cutoff. This access presumably occurs through the magnetotail. In addition to the H+, H2+, and H3+ ions primarily of local origin, energetic He, C, N, and O ions are found with solar composition. Their flux can be substantially enhanced over that of interplanetary ions at energies of 0.2 to 0.4 MeV/nuc.

  13. Time travel and chemical evolution - a look at the outer solar system

    International Nuclear Information System (INIS)

    Owen, T.

    1987-01-01

    It has been hypothesized that the chemical conditions today on the planets and moons of the outer solar system are similar to conditions on earth soon after it formed. If this is so, much can be learned about the chemistry that led to life on earth. While Jupiter is a poor terrestrial analog, its satellite Europa has a smooth icy surface that may cover a layer of liquid water tens of kilometers deep. It is possible that sunlight could filter through cracks in the ice, providing energy to drive chemical reactions in the water below the ice. It is noted that the surface of Titan may include lakes or oceans of ethane and that Triton may also have liquids on its surface. Studies of cometary nuclei will be undertaken during the Comet Rendezvous-Asteroid Flyby mission

  14. Study of Power Options for Jupiter and Outer Planet Missions

    Science.gov (United States)

    Landis, Geoffrey A.; Fincannon, James

    2015-01-01

    Power for missions to Jupiter and beyond presents a challenging goal for photovoltaic power systems, but NASA missions including Juno and the upcoming Europa Clipper mission have shown that it is possible to operate solar arrays at Jupiter. This work analyzes photovoltaic technologies for use in Jupiter and outer planet missions, including both conventional arrays, as well as analyzing the advantages of advanced solar cells, concentrator arrays, and thin film technologies. Index Terms - space exploration, spacecraft solar arrays, solar electric propulsion, photovoltaic cells, concentrator, Fresnel lens, Jupiter missions, outer planets.

  15. Colors of Outer Solar System Objects Measured with VATT

    Science.gov (United States)

    Romanishin, William; Tegler, S. C.; Consolmagno, G. J.

    2010-10-01

    Over the past 7 years, we have measured optical B-V and V-R colors for about 40 minor outer solar system objects using the 1.8-m Vatican Advanced Technology Telescope (VATT) located on Mt. Graham in southeast Arizona. We will present these colors and use them to update the discussion of colors of minor bodies in the outer solar system. We gratefully acknowledge funding from the NASA Planetary Astronomy Program to Northern Arizona University and the U. of Oklahoma which helped support this work.

  16. Photoprotective substance occurs primarily in outer layers of fish skin.

    Science.gov (United States)

    Fabacher, D L; Little, E E

    1998-01-01

    Methanol extracts of dorsal skin layers, eyes, gills, and livers from ultraviolet-B (UVB) radiation-sensitive and UVB-tolerant species of freshwater fish were examined for a substance that appears to be photoprotective. Significantly larger amounts of this substance were found in extracts of outer dorsal skin layers from both UVB-sensitive and UVB-tolerant fish when compared with extracts of inner dorsal skin layers. This substance occurred in minor amounts or was not detected in eye, gill, and liver extracts. The apparent primary function of this substance in fish is to protect the cells in outer dorsal skin layers from harmful levels of UVB radiation.

  17. Selective Essential Oils from Spice or Culinary Herbs Have High Activity against Stationary Phase and Biofilm Borrelia burgdorferi.

    Science.gov (United States)

    Feng, Jie; Zhang, Shuo; Shi, Wanliang; Zubcevik, Nevena; Miklossy, Judith; Zhang, Ying

    2017-01-01

    Although the majority of patients with acute Lyme disease can be cured with the standard 2-4 week antibiotic treatment, about 10-20% of patients continue suffering from chronic symptoms described as posttreatment Lyme disease syndrome. While the cause for this is debated, one possibility is that persister bacteria are not killed by the current Lyme antibiotics and remain active in the system. It has been reported that essential oils have antimicrobial activities and some have been used by patients with persisting Lyme disease symptoms. However, the activity of essential oils against the causative agent Borrelia burgdorferi ( B. burgdorferi ) has not been well studied. Here, we evaluated the activity of 34 essential oils against B. burgdorferi stationary phase culture as a model for persister bacteria. We found that not all essential oils had activity against the B. burgdorferi stationary phase culture, with top five essential oils (oregano, cinnamon bark, clove bud, citronella, and wintergreen) at a low concentration of 0.25% showing high anti-persister activity that is more active than the known persister drug daptomycin. Interestingly, some highly active essential oils were found to have excellent anti-biofilm ability as shown by their ability to dissolve the aggregated biofilm-like structures. The top three hits, oregano, cinnamon bark, and clove bud completely eradicated all viable cells without any regrowth in subculture in fresh medium, whereas but not citronella and wintergreen did not have this effect. Carvacrol was found to be the most active ingredient of oregano oil showing excellent activity against B. burgdorferi stationary phase cells, while other ingredients of oregano oil p-cymene and α-terpinene had no apparent activity. Future studies are needed to characterize and optimize the active essential oils in drug combination studies in vitro and in vivo and to address their safety and pharmacokinetic properties before they can be considered as a

  18. Using Landscape Analysis to Test Hypotheses about Drivers of Tick Abundance and Infection Prevalence with Borrelia burgdorferi.

    Science.gov (United States)

    Ferrell, A Michelle; Brinkerhoff, R Jory

    2018-04-12

    Patterns of vector-borne disease risk are changing globally in space and time and elevated disease risk of vector-borne infection can be driven by anthropogenic modification of the environment. Incidence of Lyme disease, caused by the bacterium Borrelia burgdorferi sensu stricto, has risen in a number of locations in North America and this increase may be driven by spatially or numerically expanding populations of the primary tick vector, Ixodes scapularis . We used a model selection approach to identify habitat fragmentation and land-use/land cover variables to test the hypothesis that the amount and configuration of forest cover at spatial scales relevant to deer, the primary hosts of adult ticks, would be the predominant determinants of tick abundance. We expected that land cover heterogeneity and amount of forest edge, a habitat thought to facilitate deer foraging and survival, would be the strongest driver of tick density and that larger spatial scales (5-10 km) would be more important than smaller scales (1 km). We generated metrics of deciduous and mixed forest fragmentation using Fragstats 4.4 implemented in ArcMap 10.3 and found, after adjusting for multicollinearity, that total forest edge within a 5 km buffer had a significant negative effect on tick density and that the proportion of forested land cover within a 10 km buffer was positively associated with density of I. scapularis nymphs. None of the 1 km fragmentation metrics were found to significantly improve the fit of the model. Elevation, previously associated with increased density of I. scapularis nymphs in Virginia, while significantly predictive in univariate analysis, was not an important driver of nymph density relative to fragmentation metrics. Our results suggest that amount of forest cover (i.e., lack of fragmentation) is the most important driver of I. scapularis density in our study system.

  19. The Western progression of lyme disease: infectious and Nonclonal Borrelia burgdorferi Sensu Lato populations in Grand Forks County, North Dakota.

    Science.gov (United States)

    Stone, Brandee L; Russart, Nathan M; Gaultney, Robert A; Floden, Angela M; Vaughan, Jefferson A; Brissette, Catherine A

    2015-01-01

    Scant attention has been paid to Lyme disease, Borrelia burgdorferi, Ixodes scapularis, or reservoirs in eastern North Dakota despite the fact that it borders high-risk counties in Minnesota. Recent reports of B. burgdorferi and I. scapularis in North Dakota, however, prompted a more detailed examination. Spirochetes cultured from the hearts of five rodents trapped in Grand Forks County, ND, were identified as B. burgdorferi sensu lato through sequence analyses of the 16S rRNA gene, the 16S rRNA gene-ileT intergenic spacer region, flaB, ospA, ospC, and p66. OspC typing revealed the presence of groups A, B, E, F, L, and I. Two rodents were concurrently carrying multiple OspC types. Multilocus sequence typing suggested the eastern North Dakota strains are most closely related to those found in neighboring regions of the upper Midwest and Canada. BALB/c mice were infected with B. burgdorferi isolate M3 (OspC group B) by needle inoculation or tick bite. Tibiotarsal joints and ear pinnae were culture positive, and B. burgdorferi M3 was detected by quantitative PCR (qPCR) in the tibiotarsal joints, hearts, and ear pinnae of infected mice. Uninfected larval I. scapularis ticks were able to acquire B. burgdorferi M3 from infected mice; M3 was maintained in I. scapularis during the molt from larva to nymph; and further, M3 was transmitted from infected I. scapularis nymphs to naive mice, as evidenced by cultures and qPCR analyses. These results demonstrate that isolate M3 is capable of disseminated infection by both artificial and natural routes of infection. This study confirms the presence of unique (nonclonal) and infectious B. burgdorferi populations in eastern North Dakota. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  20. Inter- and intra-specific pan-genomes of Borrelia burgdorferi sensu lato: genome stability and adaptive radiation

    Science.gov (United States)

    2013-01-01

    Background Lyme disease is caused by spirochete bacteria from the Borrelia burgdorferi sensu lato (B. burgdorferi s.l.) species complex. To reconstruct the evolution of B. burgdorferi s.l. and identify the genomic basis of its human virulence, we compared the genomes of 23 B. burgdorferi s.l. isolates from Europe and the United States, including B. burgdorferi sensu stricto (B. burgdorferi s.s., 14 isolates), B. afzelii (2), B. garinii (2), B. “bavariensis” (1), B. spielmanii (1), B. valaisiana (1), B. bissettii (1), and B. “finlandensis” (1). Results Robust B. burgdorferi s.s. and B. burgdorferi s.l. phylogenies were obtained using genome-wide single-nucleotide polymorphisms, despite recombination. Phylogeny-based pan-genome analysis showed that the rate of gene acquisition was higher between species than within species, suggesting adaptive speciation. Strong positive natural selection drives the sequence evolution of lipoproteins, including chromosomally-encoded genes 0102 and 0404, cp26-encoded ospC and b08, and lp54-encoded dbpA, a07, a22, a33, a53, a65. Computer simulations predicted rapid adaptive radiation of genomic groups as population size increases. Conclusions Intra- and inter-specific pan-genome sizes of B. burgdorferi s.l. expand linearly with phylogenetic diversity. Yet gene-acquisition rates in B. burgdorferi s.l. are among the lowest in bacterial pathogens, resulting in high genome stability and few lineage-specific genes. Genome adaptation of B. burgdorferi s.l. is driven predominantly by copy-number and sequence variations of lipoprotein genes. New genomic groups are likely to emerge if the current trend of B. burgdorferi s.l. population expansion continues. PMID:24112474

  1. Role of acetyl-phosphate in activation of the Rrp2-RpoN-RpoS pathway in Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Haijun Xu

    2010-09-01

    Full Text Available Borrelia burgdorferi, the Lyme disease spirochete, dramatically alters its transcriptome and proteome as it cycles between the arthropod vector and mammalian host. During this enzootic cycle, a novel regulatory network, the Rrp2-RpoN-RpoS pathway (also known as the σ(54-σ(S sigma factor cascade, plays a central role in modulating the differential expression of more than 10% of all B. burgdorferi genes, including the major virulence genes ospA and ospC. However, the mechanism(s by which the upstream activator and response regulator Rrp2 is activated remains unclear. Here, we show that none of the histidine kinases present in the B. burgdorferi genome are required for the activation of Rrp2. Instead, we present biochemical and genetic evidence that supports the hypothesis that activation of the Rrp2-RpoN-RpoS pathway occurs via the small, high-energy, phosphoryl-donor acetyl phosphate (acetyl∼P, the intermediate of the Ack-Pta (acetate kinase-phosphate acetyltransferase pathway that converts acetate to acetyl-CoA. Supplementation of the growth medium with acetate induced activation of the Rrp2-RpoN-RpoS pathway in a dose-dependent manner. Conversely, the overexpression of Pta virtually abolished acetate-induced activation of this pathway, suggesting that acetate works through acetyl∼P. Overexpression of Pta also greatly inhibited temperature and cell density-induced activation of RpoS and OspC, suggesting that these environmental cues affect the Rrp2-RpoN-RpoS pathway by influencing acetyl∼P. Finally, overexpression of Pta partially reduced infectivity of B. burgdorferi in mice. Taken together, these findings suggest that acetyl∼P is one of the key activating molecule for the activation of the Rrp2-RpoN-RpoS pathway and support the emerging concept that acetyl∼P can serve as a global signal in bacterial pathogenesis.

  2. Serological and molecular evidence for spotted fever group Rickettsia and Borrelia burgdorferi sensu lato co-infections in The Netherlands.

    Science.gov (United States)

    Koetsveld, Joris; Tijsse-Klasen, Ellen; Herremans, Tineke; Hovius, Joppe W R; Sprong, Hein

    2016-03-01

    Only a few reported cases indicate that Rickettsia helvetica and Rickettsia monacensis can cause disease in humans. Exposure to these two spotted fever group (SFG) rickettsiae occurs through bites of Ixodes ricinus, also the primary vector of Lyme borreliosis in Europe. To date, it is unclear how often exposure to these two microorganisms results in infection or disease. We show that of all the Borrelia burgdorferi s.l.-positive ticks, 25% were co-infected with rickettsiae. Predominantly R. helvetica was detected while R. monacensis was only found in approximately 2% of the ticks. In addition, exposure to tick-borne pathogens was compared by serology in healthy blood donors, erythema migrans (EM)-patients, and patients suspected of Lyme neuroborreliosis (LNB). As could be expected, seroreactivity against B. burgdorferi sensu lato was lower in blood donors (6%) compared to EM patients (34%) and suspected LNB cases (64%). Interestingly, seroreactivity against SFG Rickettsia antigens was not detected in serum samples from blood donors (0%), but 6% of the EM patients and 21% of the LNB suspects showed anti-rickettsial antibodies. Finally, the presence of B. burgdorferi s.l. and Rickettsia spp. in cerebrospinal fluid samples of a large cohort of patients suspected of LNB (n=208) was investigated by PCR. DNA of B. burgdorferi s.l., R. helvetica and R. monacensis was detected in seventeen, four and one patient, respectively. In conclusion, our data show that B. burgdorferi s.l. and SFG rickettsiae co-infection occurs in Dutch I. ricinus and that Lyme borreliosis patients, or patients suspected of Lyme borreliosis, are indeed exposed to both tick-borne pathogens. Whether SFG rickettsiae actually cause disease, and whether co-infections alter the clinical course of Lyme borreliosis, is not clear from our data, and warrants further investigation. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Analysis of an ordered, comprehensive STM mutant library in infectious Borrelia burgdorferi: insights into the genes required for mouse infectivity.

    Directory of Open Access Journals (Sweden)

    Tao Lin

    Full Text Available The identification of genes important in the pathogenesis of Lyme disease Borrelia has been hampered by exceedingly low transformation rates in low-passage, infectious organisms. Using the infectious, moderately transformable B. burgdorferi derivative 5A18NP1 and signature-tagged versions of the Himar1 transposon vector pGKT, we have constructed a defined transposon library for the efficient genome-wide investigation of genes required for wild-type pathogenesis, in vitro growth, physiology, morphology, and plasmid replication. To facilitate analysis, the insertion sites of 4,479 transposon mutants were determined by sequencing. The transposon insertions were widely distributed across the entire B. burgdorferi genome, with an average of 2.68 unique insertion sites per kb DNA. The 10 linear plasmids and 9 circular plasmids had insertions in 33 to 100 percent of their predicted genes. In contrast, only 35% of genes in the 910 kb linear chromosome had incapacitating insertions; therefore, the remaining 601 chromosomal genes may represent essential gene candidates. In initial signature-tagged mutagenesis (STM analyses, 434 mutants were examined at multiple tissue sites for infectivity in mice using a semi-quantitative, Luminex-based DNA detection method. Examples of genes found to be important in mouse infectivity included those involved in motility, chemotaxis, the phosphoenolpyruvate phosphotransferase system, and other transporters, as well as putative plasmid maintenance genes. Availability of this ordered STM library and a high-throughput screening method is expected to lead to efficient assessment of the roles of B. burgdorferi genes in the infectious cycle and pathogenesis of Lyme disease.

  4. Induction of type I and type III interferons by Borrelia burgdorferi correlates with pathogenesis and requires linear plasmid 36.

    Directory of Open Access Journals (Sweden)

    Michelle A Krupna-Gaylord

    Full Text Available The capacity for Borrelia burgdorferi to cause disseminated infection in humans or mice is associated with the genotype of the infecting strain. The cytokine profiles elicited by B. burgdorferi clinical isolates of different genotype (ribosomal spacer type groups were assessed in a human PBMC co-incubation model. RST1 isolates, which are more frequently associated with disseminated Lyme disease in humans and mice, induced significantly higher levels of IFN-α and IFN-λ1/IL29 relative to RST3 isolates, which are less frequently associated with disseminated infection. No differences in the protein concentrations of IFN-γ, IL-1β, IL-6, IL-8, IL-10 or TNF-α were observed between isolates of differing genotype. The ability of B. burgdorferi to induce type I and type III IFNs was completely dependent on the presence of linear plasmid (lp 36. An lp36-deficient B. burgdorferi mutant adhered to, and was internalized by, PBMCs and specific dendritic cell (DC subsets less efficiently than its isogenic B31 parent strain. The association defect with mDC1s and pDCs could be restored by complementation of the mutant with the complete lp36. The RST1 clinical isolates studied were found to contain a 2.5-kB region, located in the distal one-third of lp36, which was not present in any of the RST3 isolates tested. This divergent region of lp36 may encode one or more factors required for optimal spirochetal recognition and the production of type I and type III IFNs by human DCs, thus suggesting a potential role for DCs in the pathogenesis of B. burgdorferi infection.

  5. Selective Essential Oils from Spice or Culinary Herbs Have High Activity against Stationary Phase and Biofilm Borrelia burgdorferi

    Science.gov (United States)

    Feng, Jie; Zhang, Shuo; Shi, Wanliang; Zubcevik, Nevena; Miklossy, Judith; Zhang, Ying

    2017-01-01

    Although the majority of patients with acute Lyme disease can be cured with the standard 2–4 week antibiotic treatment, about 10–20% of patients continue suffering from chronic symptoms described as posttreatment Lyme disease syndrome. While the cause for this is debated, one possibility is that persister bacteria are not killed by the current Lyme antibiotics and remain active in the system. It has been reported that essential oils have antimicrobial activities and some have been used by patients with persisting Lyme disease symptoms. However, the activity of essential oils against the causative agent Borrelia burgdorferi (B. burgdorferi) has not been well studied. Here, we evaluated the activity of 34 essential oils against B. burgdorferi stationary phase culture as a model for persister bacteria. We found that not all essential oils had activity against the B. burgdorferi stationary phase culture, with top five essential oils (oregano, cinnamon bark, clove bud, citronella, and wintergreen) at a low concentration of 0.25% showing high anti-persister activity that is more active than the known persister drug daptomycin. Interestingly, some highly active essential oils were found to have excellent anti-biofilm ability as shown by their ability to dissolve the aggregated biofilm-like structures. The top three hits, oregano, cinnamon bark, and clove bud completely eradicated all viable cells without any regrowth in subculture in fresh medium, whereas but not citronella and wintergreen did not have this effect. Carvacrol was found to be the most active ingredient of oregano oil showing excellent activity against B. burgdorferi stationary phase cells, while other ingredients of oregano oil p-cymene and α-terpinene had no apparent activity. Future studies are needed to characterize and optimize the active essential oils in drug combination studies in vitro and in vivo and to address their safety and pharmacokinetic properties before they can be considered as a

  6. Space weathering and the color indexes of minor bodies in the outer Solar System

    Science.gov (United States)

    Kaňuchová, Zuzana; Brunetto, Rosario; Melita, Mario; Strazzulla, Giovanni

    2012-09-01

    The surfaces of small bodies in the outer Solar System are rich in organic compounds and carbonaceous refractories mixed with ices and silicates. As made clear by dedicated laboratory experiments space weathering (e.g. energetic ion bombardment) can produce red colored materials starting from bright and spectrally flat ices. In a classical scenario, the space weathering processes “nurture” alter the small bodies surface spectra but are in competition with resurfacing agents that restore the original colors, and the result of these competing processes continuously modifying the surfaces is supposed to be responsible for the observed spectral variety of those small bodies. However an alternative point of view is that the different colors are due to “nature” i.e. to the different primordial composition of different objects. In this paper we present a model, based on laboratory results, that gives an original contribution to the “nature” vs. “nurture” debate by addressing the case of surfaces showing different fractions of rejuvenated vs. space weathered surface, and calculating the corresponding color variations. We will show how a combination of increasing dose coupled to different resurfacing can reproduce the whole range of observations of small outer Solar System bodies. Here we demonstrate, for the first time that objects having a fully weathered material turn back in the color-color diagrams. At the same time, object with the different ratio of pristine and weathered surface areas lay on specific lines in color-color diagrams, if exposed to the same amount of irradiation.

  7. Prototype repository - Microbes in the retrieved outer section

    International Nuclear Information System (INIS)

    Arlinger, Johanna; Bengtsson, Andreas; Edlund, Johanna; Eriksson, Lena; Johansson, Jessica; Lydmark, Sara; Rabe, Lisa; Pedersen, Karsten

    2013-10-01

    The Prototype repository is an international project to build and study a full-scale model of the planned Swedish final repository for spent nuclear fuel. The Prototype consists of two sections with four and two full-scale copper canisters, respectively. In 2011, the outer section with two canisters (nos. 5 and 6) was excavated. Groundwater surrounding the Prototype has been demonstrated to include microorganisms such as iron-reducing bacteria (IRB) and sulphate-reducing bacteria (SRB) with the ability to affect the repository through reduction of structural Fe(III) in the buffer or by the production of sulphide, respectively. During excavation, samples were taken for microbiological and molecular biological analysis from backfill, buffer, and canister surfaces and analysed with an emphasis on microbial presence and number. The underground environment is anaerobic, but the construction of a repository will raise the oxygen levels. Oxygen is not favourable for the longevity of the copper canister, but oxygen levels will decrease over time, partly due to microbial activity that consumes oxygen. Therefore, evaluating the presence and numbers of the heterotrophic aerobic bacteria that consume oxygen as well as monitoring the oxygen levels are important. The oxygen content of the bentonite itself is also a primary concern, and a method for measuring how the oxygen diffuses through the clay has long been needed. In the work reported here, we performed two pilot studies to address this need. One of these studies tested a method for differentiating between oxygen saturation in aerobic versus anaerobic bentonite; this method has potential for further development. The tunnel above the Prototype canisters was backfilled with a mixture of bentonite and crushed rock. Sixty-three randomly chosen samples from a cross-section through the backfill were analysed for culturable heterotrophic aerobic bacteria. All but one exhibited growth, with four samples exhibiting numbers over 106

  8. Prototype repository - Microbes in the retrieved outer section

    Energy Technology Data Exchange (ETDEWEB)

    Arlinger, Johanna; Bengtsson, Andreas; Edlund, Johanna; Eriksson, Lena; Johansson, Jessica; Lydmark, Sara; Rabe, Lisa; Pedersen, Karsten [Microbial Analytics Sweden, Moelnlycke (Sweden)

    2013-10-15

    The Prototype repository is an international project to build and study a full-scale model of the planned Swedish final repository for spent nuclear fuel. The Prototype consists of two sections with four and two full-scale copper canisters, respectively. In 2011, the outer section with two canisters (nos. 5 and 6) was excavated. Groundwater surrounding the Prototype has been demonstrated to include microorganisms such as iron-reducing bacteria (IRB) and sulphate-reducing bacteria (SRB) with the ability to affect the repository through reduction of structural Fe(III) in the buffer or by the production of sulphide, respectively. During excavation, samples were taken for microbiological and molecular biological analysis from backfill, buffer, and canister surfaces and analysed with an emphasis on microbial presence and number. The underground environment is anaerobic, but the construction of a repository will raise the oxygen levels. Oxygen is not favourable for the longevity of the copper canister, but oxygen levels will decrease over time, partly due to microbial activity that consumes oxygen. Therefore, evaluating the presence and numbers of the heterotrophic aerobic bacteria that consume oxygen as well as monitoring the oxygen levels are important. The oxygen content of the bentonite itself is also a primary concern, and a method for measuring how the oxygen diffuses through the clay has long been needed. In the work reported here, we performed two pilot studies to address this need. One of these studies tested a method for differentiating between oxygen saturation in aerobic versus anaerobic bentonite; this method has potential for further development. The tunnel above the Prototype canisters was backfilled with a mixture of bentonite and crushed rock. Sixty-three randomly chosen samples from a cross-section through the backfill were analysed for culturable heterotrophic aerobic bacteria. All but one exhibited growth, with four samples exhibiting numbers over 106

  9. Thermographic studies of outer target heat fluxes on KSTAR

    Directory of Open Access Journals (Sweden)

    H.H. Lee

    2017-08-01

    Full Text Available A new infra-red (IR thermography system with high spatial resolution has been installed on KSTAR and is now mainly applied to measure the outer divertor heat load profile. The first measurement results of the outer divertor heat load profiles between ELMs have been applied to characterize the inter-ELMs outer divertor heat loads in KSTAR H-mode plasmas. In particular, the power decay length (λq of the divertor heat load profile has been determined by fitting the profile to a convolution of an exponential decay and a Gaussian function. The analysis on the power decay length shows a good agreement with the recent multi-machine λq scaling, which predicts λq of the inter-ELMs divertor heat load to be ∼1 mm under the standard H-mode scenario in ITER. The divertor IR thermography system has also successfully measured the strike point splitting of the outer divertor heat flux during the application of resonant magnetic perturbation (RMP fields. In addition, it has provided a clear evidence that the strike point splitting pattern depends on the RMP fields configuration.

  10. 75 FR 71734 - Outer Continental Shelf (OCS), Scientific Committee (SC)

    Science.gov (United States)

    2010-11-24

    ... Environmental Studies Program (ESP) and environmental aspects of the offshore energy and marine minerals... oceanography, as well as studies of the social and economic impacts of OCS energy and marine minerals... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management, Regulation and Enforcement Outer...

  11. Detergent organisation in crystals of monomeric outer membrane phospholipase A

    NARCIS (Netherlands)

    Snijder, HJ; Timmins, PA; Kalk, KH; Dijkstra, BW

    The structure of the detergent in crystals of outer membrane phospholipase A (OMPLA) has been determined using neutron diffraction contrast variation. Large crystals were soaked in stabilising solutions, each containing a different H2O/D2O contrast. From the neutron diffraction at five contrasts,

  12. Exploring bacterial outer membrane barrier to combat bad bugs.

    Science.gov (United States)

    Ghai, Ishan; Ghai, Shashank

    2017-01-01

    One of the main fundamental mechanisms of antibiotic resistance in Gram-negative bacteria comprises an effective change in the membrane permeability to antibiotics. The Gram-negative bacterial complex cell envelope comprises an outer membrane that delimits the periplasm from the exterior environment. The outer membrane contains numerous protein channels, termed as porins or nanopores, which are mainly involved in the influx of hydrophilic compounds, including antibiotics. Bacterial adaptation to reduce influx through these outer membrane proteins (Omps) is one of the crucial mechanisms behind antibiotic resistance. Thus to interpret the molecular basis of the outer membrane permeability is the current challenge. This review attempts to develop a state of knowledge pertinent to Omps and their effective role in antibiotic influx. Further, it aims to study the bacterial response to antibiotic membrane permeability and hopefully provoke a discussion toward understanding and further exploration of prospects to improve our knowledge on physicochemical parameters that direct the translocation of antibiotics through the bacterial membrane protein channels.

  13. Outer casing of the AA antiproton production target

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long (actually a row of 11 rods, each 1 cm long) and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing made of stainless steel. The casing had fins for forced-air cooling.

  14. A progenitor of the outer membrane LamB trimer.

    OpenAIRE

    Stader, J; Silhavy, T J

    1988-01-01

    During its localization to the outer membrane, LamB possesses distinctive biochemical properties as it passes through the cytoplasmic membrane. Because LamB entered this dynamic state with an attached signal sequence and leaves after cleavage, we call this export-related form of LamB the early-translocation form (et-LamB).

  15. Ethane Ices in the Outer Solar System: Spectroscopy and Chemistry

    Science.gov (United States)

    Hudson, R. L.; Moore, M. H.; Raines, L. L.

    2009-01-01

    We report recent experiments on ethane ices made at temperatures applicable to the outer Solar System. New near- and mid-infrared data for crystalline and amorphous ethane, including new spectra for a seldom-studied solid phase that exists at 35-55 K, are presented along with radiation-chemical experiments showing the formation of more-complex hydrocarbons

  16. The outer membrane protein assembly machinery of Neisseria meningitidis

    NARCIS (Netherlands)

    Volokhina, E.B.|info:eu-repo/dai/nl/304837202

    2009-01-01

    Gram-negative bacteria are characterized by a cell envelope consisting of an inner membrane (IM) and an outer membrane (OM), which are separated by the peptidoglycan-containing periplasm. While the integral IM proteins are alpha-helical, all but one known integral OM proteins (OMPs) are

  17. Exploring bacterial outer membrane barrier to combat bad bugs

    Directory of Open Access Journals (Sweden)

    Ghai I

    2017-08-01

    Full Text Available Ishan Ghai,1 Shashank Ghai2 1School of Engineering and Life Sciences, Jacobs University, Bremen, 2Leibniz University, Hannover, Germany Abstract: One of the main fundamental mechanisms of antibiotic resistance in Gram-negative bacteria comprises an effective change in the membrane permeability to antibiotics. The Gram-negative bacterial complex cell envelope comprises an outer membrane that delimits the periplasm from the exterior environment. The outer membrane contains numerous protein channels, termed as porins or nanopores, which are mainly involved in the influx of hydrophilic compounds, including antibiotics. Bacterial adaptation to reduce influx through these outer membrane proteins (Omps is one of the crucial mechanisms behind antibiotic resistance. Thus to interpret the molecular basis of the outer membrane permeability is the current challenge. This review attempts to develop a state of knowledge pertinent to Omps and their effective role in antibiotic influx. Further, it aims to study the bacterial response to antibiotic membrane permeability and hopefully provoke a discussion toward understanding and further exploration of prospects to improve our knowledge on physicochemical parameters that direct the translocation of antibiotics through the bacterial membrane protein channels. Keywords: antibiotics, Gram-negative bacteria, cell envelope, protein channels, nanopores, influx, antibiotic resistance

  18. Disagreement between the results from three commercial tests for the detection of Borrelia-specific serum antibodies in the Netherlands associated with antibiotic treatment for Lyme borreliosis: a retrospective study.

    NARCIS (Netherlands)

    van Gorkom, T; Kremer, K; Voet, W; Notermans, D W; Vlaminckx, B J M; Sankatsing, S U C; Thijsen, S F T

    2017-01-01

    The diagnosis of Lyme borreliosis is challenging because of the often non-specific symptoms and persisting antibodies after infection. We investigated the diagnostic characteristics of two enzyme-linked immunosorbent assays (ELISAs) and an immunoblot for the detection of Borrelia-specific serum

  19. Wisps in the outer edge of the Keeler Gap

    Science.gov (United States)

    Tiscareno, Matthew S.; Arnault, Ethan G.

    2015-11-01

    Superposed upon the relatively smooth outer edge of the Keeler Gap are a system of "wisps," which appear to be ring material protruding inward into the gap, usually with a sharp trailing edge and a smooth gradation back to the background edge location on the leading side (Porco et al. 2005, Science). The radial amplitude of wisps is usually 0.5 to 1 km, and their azimuthal extent is approximately a degree of longitude (~2400 km). Wisps are likely caused by an interplay between Daphnis (and perhaps other moons) and embedded moonlets within the ring, though the details remain unclear.Aside from the wisps, the Keeler Gap outer edge is the only one of the five sharp edges in the outer part of Saturn's A ring that is reasonably smooth in appearance (Tiscareno et al. 2005, DPS), with occultations indicating residuals less than 1 km upon a possibly non-zero eccentricity (R.G. French, personal communication, 2014). The other four (the inner and outer edges of the Encke Gap, the inner edge of the Keeler Gap, and the outer edge of the A ring itself) are characterized by wavy structure at moderate to high spatial frequencies, with amplitudes ranging from 2 to 30 km (Tiscareno et al. 2005, DPS).We will present a catalogue of wisp detections in Cassini images. We carry out repeated gaussian fits of the radial edge location in order to characterize edge structure and visually scan those fitted edges in order to detect wisps. With extensive coverage in longitude and in time, we will report on how wisps evolve and move, both within an orbit period and on longer timescales. We will also report on the frequency and interpretation of wisps that deviate from the standard morphology. We will discuss the implications of our results for the origin and nature of wisps, and for the larger picture of how masses interact within Saturn's rings.

  20. Erosion, Transportation, and Deposition on Outer Solar System Satellites: Landform Evolution Modeling Studies

    Science.gov (United States)

    Moore, Jeffrey Morgan; Howard, Alan D.; Schenk, Paul M.

    2013-01-01

    Mass movement and landform degradation reduces topographic relief by moving surface materials to a lower gravitational potential. In addition to the obvious role of gravity, abrasive mechanical erosion plays a role, often in combination with the lowering of cohesion, which allows disaggregation of the relief-forming material. The identification of specific landform types associated with mass movement and landform degradation provides information about local sediment particle size and abundance and transportation processes. Generally, mass movements can be classified in terms of the particle sizes of the transported material and the speed the material moved during transport. Most degradation on outer planet satellites appears consistent with sliding or slumping, impact erosion, and regolith evolution. Some satellites, such as Callisto and perhaps Hyperion and Iapetus, have an appearance that implies that some additional process is at work, most likely sublimation-driven landform modification and mass wasting. A variant on this process is thermally driven frost segregation as seen on all three icy Galilean satellites and perhaps elsewhere. Titan is unique among outer planet satellites in that Aeolian and fluvial processes also operate to erode, transport, and deposit material. We will evaluate the sequence and extent of various landform-modifying erosional and volatile redistribution processes that have shaped these icy satellites using a 3-D model that simulates the following surface and subsurface processes: 1) sublimation and re-condensation of volatiles; 2) development of refractory lag deposits; 3) disaggregation and downward sloughing of surficial material; 4) radiative heating/cooling of the surface (including reflection, emission, and shadowing by other surface elements); 5) thermal diffusion; and 6) vapor diffusion. The model will provide explicit simulations of landform development and thusly predicts the topographic and volatile evolution of the surface