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Sample records for carry flea-borne rickettsia

  1. Ixodes ricinus ticks are reservoir hosts for Rickettsia helvetica and potentially carry flea-borne Rickettsia species.

    NARCIS (Netherlands)

    Sprong, H.; Wielinga, P.R.; Fonville, M.; Reusken, C.; Brandenburg, A.H.; Borgsteede, F.H.M.

    2009-01-01

    Background - Hard ticks have been identified as important vectors of rickettsiae causing the spotted fever syndrome. Tick-borne rickettsiae are considered to be emerging, but only limited data are available about their presence in Western Europe, their natural life cycle and their reservoir hosts.

  2. Ixodes ricinus ticks are reservoir hosts for Rickettsia helvetica and potentially carry flea-borne Rickettsia species

    Directory of Open Access Journals (Sweden)

    Gaasenbeek Cor

    2009-09-01

    Full Text Available Abstract Background Hard ticks have been identified as important vectors of rickettsiae causing the spotted fever syndrome. Tick-borne rickettsiae are considered to be emerging, but only limited data are available about their presence in Western Europe, their natural life cycle and their reservoir hosts. Ixodes ricinus, the most prevalent tick species, were collected and tested from different vegetation types and from potential reservoir hosts. In one biotope area, the annual and seasonal variability of rickettsiae infections of the different tick stages were determined for 9 years. Results The DNA of the human pathogen R. conorii as well as R. helvetica, R. sp. IRS and R. bellii-like were found. Unexpectedly, the DNA of the highly pathogenic R. typhi and R. prowazekii and 4 other uncharacterized Rickettsia spp. related to the typhus group were also detected in I. ricinus. The presence of R. helvetica in fleas isolated from small rodents supported our hypothesis that cross-infection can occur under natural conditions, since R. typhi/prowazekii and R. helvetica as well as their vectors share rodents as reservoir hosts. In one biotope, the infection rate with R. helvetica was ~66% for 9 years, and was comparable between larvae, nymphs, and adults. Larvae caught by flagging generally have not yet taken a blood meal from a vertebrate host. The simplest explanation for the comparable prevalence of R. helvetica between the defined tick stages is, that R. helvetica is vertically transmitted through the next generation with high efficiency. The DNA of R. helvetica was also present in whole blood from mice, deer and wild boar. Conclusion Besides R. helvetica, unexpected rickettsiae are found in I. ricinus ticks. We propose that I. ricinus is a major reservoir host for R. helvetica, and that vertebrate hosts play important roles in the further geographical dispersion of rickettsiae.

  3. Detection of flea-borne Rickettsia species in the Western Himalayan region of India

    Directory of Open Access Journals (Sweden)

    R Chahota

    2015-01-01

    Full Text Available Human infections by various rickettsial species are frequently reported globally. We investigated a flea-borne rickettsial outbreak infecting 300 people in Western Himalayan region of India. Arthropod vectors (ticks and fleas and animal and human blood samples from affected households were analysed by gltA and ompB genes based polymerase chain reaction (PCR. Rat flea (Ceratophyllus fasciatus samples were found harbouring a Rickettsia sp. Phylogenetic analysis based on gltA gene using PHYLIP revealed that the detected Rickettsia sp. has 100% identity with SE313 and RF2125 strains of Rickettsia sp. of flea origin from Egypt and Thai-Myanmar border, respectively and cf1 and 5 strains from fleas and lice from the USA. But, the nucleotide sequence of genetically variable gene ompB of R14 strain was found closely related to cf9 strain, reported from Ctenocephalides felis fleas. These results highlight the public health importance of such newly discovered or less recognised Rickettsia species/strains, harboured by arthropod vectors like fleas.

  4. Two Pathogens and One Disease: Detection and Identification of Flea-Borne Rickettsiae in Areas Endemic for Murine Typhus in California

    Science.gov (United States)

    EREMEEVA, MARINA E.; KARPATHY, SANDOR E.; KRUEGER, LAURA; HAYES, ERICA K.; WILLIAMS, ASHLEY M.; ZALDIVAR, YAMITZEL; BENNETT, STEPHEN; CUMMINGS, ROBERT; TILZER, ART; VELTEN, ROBERT K.; KERR, NELSON; DASCH, GREGORY A.; HU, RENJIE

    2018-01-01

    Results of an environmental assessment conducted in a newly emergent focus of murine typhus in southern California are described. Opossums, Didelphis virginiana Kerr, infested with cat fleas, Ctenocephalides felis Buché, in the suburban area were abundant. Animal and flea specimens were tested for the DNA of two flea-borne rickettsiae, Rickettsia typhi and Rickettsia felis. R. felis was commonly detected in fleas collected throughout this area while R. typhi was found at a much lower prevalence in the vicinity of just 7 of 14 case-patient homes identified. DNA of R. felis, but not R. typhi, was detected in renal, hepatic, and pulmonary tissues of opossums. In contrast, there were no hematologic polymerase chain reaction findings of R. felis or R. typhi in opossums, rats, and cats within the endemic area studied. Our data suggest a significant probability of human exposure to R. felis in the area studied; however, disease caused by this agent is not recognized by the medical community and may be misdiagnosed as murine typhus using nondiscriminatory serologic methods. PMID:23270180

  5. Molecular detection of Rickettsia felis and Candidatus Rickettsia Asemboensis in fleas from human habitats, Asembo, Kenya

    OpenAIRE

    Jiang, J.; Maina, A.N; Knobel, D.L.; Cleaveland, S.; Laudisoit, A.; Wamburu, K.; Ogola, E.; Parola, P.; Breiman, R.F.; Njenga, M.K.; Richards, A.L.

    2013-01-01

    The flea-borne rickettsioses murine typhus (Rickettsia typhi) and flea-borne spotted fever (FBSF) (Rickettsia felis) are febrile diseases distributed among humans worldwide. Murine typhus has been known to be endemic to Kenya since the 1950s, but FBSF was only recently documented in northeastern (2010) and western (2012) Kenya. To characterize the potential exposure of humans in Kenya to flea-borne rickettsioses, a total of 330 fleas (134 pools) including 5 species (Xenopsylla cheopis, Ctenoc...

  6. RICKETTSIA

    Directory of Open Access Journals (Sweden)

    Nova Pramestuti

    2012-10-01

    Full Text Available Mungkin sebagian orang belum mengetahui bahkan baru mendengar tentang Rickettsia. Di Indonesia, skrining terhadap kasus Rickettsia ini masih jarang dan belum banyak dilakukan penelitian. Rickettsia sebenarnya merupakan bakteri yang mempunyai sifat parasit obligat intrasel uler, berukuran kecil (0,3-0,5 x 0,8-2,0 µm, mempunyai bentuk coccobacilli, gram negatif, tidak berflagel (kecuali Rickettsia prowazekii, dan mengalami pembelahan ganda dalam set pejamu. Rickettsia dianggap sebagai kelompok bakteri yang terpisah karena mempunyai ciri sebagai agent penyakit yang ditularkan oleh vektor arthropoda (tungau, pinjal, caplak, dan kutu.

  7. Rickettsial Infections among Ctenocephalides felis and Host Animals during a Flea-Borne Rickettsioses Outbreak in Orange County, California

    Science.gov (United States)

    Fogarty, Carrie; Krueger, Laura; Macaluso, Kevin R.; Odhiambo, Antony; Nguyen, Kiet; Farris, Christina M.; Luce-Fedrow, Alison; Bennett, Stephen; Jiang, Ju; Sun, Sokanary; Cummings, Robert F.; Richards, Allen L.

    2016-01-01

    Due to a resurgence of flea-borne rickettsioses in Orange County, California, we investigated the etiologies of rickettsial infections of Ctenocephalides felis, the predominant fleas species obtained from opossums (Didelphis virginiana) and domestic cats (Felis catus), collected from case exposure sites and other areas in Orange County. In addition, we assessed the prevalence of IgG antibodies against spotted fever group (SFGR) and typhus group (TGR) rickettsiae in opossum sera. Of the 597 flea specimens collected from opossums and cats, 37.2% tested positive for Rickettsia. PCR and sequencing of rickettsial genes obtained from C. felis flea DNA preparations revealed the presence of R. typhi (1.3%), R. felis (28.0%) and R. felis-like organisms (7.5%). Sera from opossums contained TGR-specific (40.84%), but not SFGR-specific antibodies. The detection of R. felis and R. typhi in the C. felis fleas in Orange County highlights the potential risk for human infection with either of these pathogens, and underscores the need for further investigations incorporating specimens from humans, animal hosts, and invertebrate vectors in endemic areas. Such studies will be essential for establishing a link in the ongoing flea-borne rickettsioses outbreaks. PMID:27537367

  8. Outbreaks of Rickettsia felis in Kenya and Senegal, 2010

    Centers for Disease Control (CDC) Podcasts

    2010-06-09

    This podcast describes the outbreak of Rickettsia felis in Kenya between August 2006 and June 2008, and in rural Senegal from November 2008 through July 2009. CDC infectious disease pathologist Dr. Chris Paddock discusses what researchers learned about this flea-borne disease and how to prevent infection.  Created: 6/9/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/24/2010.

  9. Identification of Dermacentor reticulatus Ticks Carrying Rickettsia raoultii on Migrating Jackal, Denmark

    DEFF Research Database (Denmark)

    Schou, Kirstine Klitgaard; Chriél, Mariann; Isbrand, Anastasia

    2017-01-01

    From a migrating golden jackal (Canis aureus), we retrieved 21 live male Dermacentor reticulatus ticks, a species not previously reported from wildlife in Denmark. We identified Rickettsia raoultii from 18 (86%) of the ticks. This bacterium is associated with scalp eschar and neck lymphadenopathy...

  10. Molecular detection of Rickettsia felis and Candidatus Rickettsia asemboensis in fleas from human habitats, Asembo, Kenya.

    Science.gov (United States)

    Jiang, Ju; Maina, Alice N; Knobel, Darryn L; Cleaveland, Sarah; Laudisoit, Anne; Wamburu, Kabura; Ogola, Eric; Parola, Philippe; Breiman, Robert F; Njenga, M Kariuki; Richards, Allen L

    2013-08-01

    The flea-borne rickettsioses murine typhus (Rickettsia typhi) and flea-borne spotted fever (FBSF) (Rickettsia felis) are febrile diseases distributed among humans worldwide. Murine typhus has been known to be endemic to Kenya since the 1950s, but FBSF was only recently documented in northeastern (2010) and western (2012) Kenya. To characterize the potential exposure of humans in Kenya to flea-borne rickettsioses, a total of 330 fleas (134 pools) including 5 species (Xenopsylla cheopis, Ctenocephalides felis, Ctenocephalides canis, Pulex irritans, and Echidnophaga gallinacea) were collected from domestic and peridomestic animals and from human dwellings within Asembo, western Kenya. DNA was extracted from the 134 pooled flea samples and 89 (66.4%) pools tested positively for rickettsial DNA by 2 genus-specific quantitative real-time PCR (qPCR) assays based upon the citrate synthase (gltA) and 17-kD antigen genes and the Rfelis qPCR assay. Sequences from the 17-kD antigen gene, the outer membrane protein (omp)B, and 2 R. felis plasmid genes (pRF and pRFd) of 12 selected rickettsia-positive samples revealed a unique Rickettsia sp. (n=11) and R. felis (n=1). Depiction of the new rickettsia by multilocus sequence typing (MLST) targeting the 16S rRNA (rrs), 17-kD antigen gene, gltA, ompA, ompB, and surface cell antigen 4 (sca4), shows that it is most closely related to R. felis but genetically dissimilar enough to be considered a separate species provisionally named Candidatus Rickettsia asemboensis. Subsequently, 81 of the 134 (60.4%) flea pools tested positively for Candidatus Rickettsia asemboensis by a newly developed agent-specific qPCR assay, Rasemb. R. felis was identified in 9 of the 134 (6.7%) flea pools, and R. typhi the causative agent of murine typhus was not detected in any of 78 rickettsia-positive pools assessed using a species-specific qPCR assay, Rtyph. Two pools were found to contain both R. felis and Candidatus Rickettsia asemboensis DNA and 1 pool

  11. Retracing the evolutionary path that led to flea-borne transmission of Yersinia pestis.

    Science.gov (United States)

    Sun, Yi-Cheng; Jarrett, Clayton O; Bosio, Christopher F; Hinnebusch, B Joseph

    2014-05-14

    Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced cyclic-di-GMP-mediated bacterial biofilm formation in the flea foregut, which greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Ecological Opportunity, Evolution, and the Emergence of Flea-Borne Plague.

    Science.gov (United States)

    Hinnebusch, B Joseph; Chouikha, Iman; Sun, Yi-Cheng

    2016-07-01

    The plague bacillus Yersinia pestis is unique among the pathogenic Enterobacteriaceae in utilizing an arthropod-borne transmission route. Transmission by fleabite is a recent evolutionary adaptation that followed the divergence of Y. pestis from the closely related food- and waterborne enteric pathogen Yersinia pseudotuberculosis A combination of population genetics, comparative genomics, and investigations of Yersinia-flea interactions have disclosed the important steps in the evolution and emergence of Y. pestis as a flea-borne pathogen. Only a few genetic changes, representing both gene gain by lateral transfer and gene loss by loss-of-function mutation (pseudogenization), were fundamental to this process. The emergence of Y. pestis fits evolutionary theories that emphasize ecological opportunity in adaptive diversification and rapid emergence of new species. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  13. Role of the Yersinia pestis yersiniabactin iron acquisition system in the incidence of flea-borne plague.

    Directory of Open Access Journals (Sweden)

    Florent Sebbane

    2010-12-01

    Full Text Available Plague is a flea-borne zoonosis caused by the bacterium Yersinia pestis. Y. pestis mutants lacking the yersiniabactin (Ybt siderophore-based iron transport system are avirulent when inoculated intradermally but fully virulent when inoculated intravenously in mice. Presumably, Ybt is required to provide sufficient iron at the peripheral injection site, suggesting that Ybt would be an essential virulence factor for flea-borne plague. Here, using a flea-to-mouse transmission model, we show that a Y. pestis strain lacking the Ybt system causes fatal plague at low incidence when transmitted by fleas. Bacteriology and histology analyses revealed that a Ybt-negative strain caused only primary septicemic plague and atypical bubonic plague instead of the typical bubonic form of disease. The results provide new evidence that primary septicemic plague is a distinct clinical entity and suggest that unusual forms of plague may be caused by atypical Y. pestis strains.

  14. Serological evidence of exposure to Rickettsia felis and Rickettsia typhi in Australian veterinarians.

    Science.gov (United States)

    Teoh, Yen Thon; Hii, Sze Fui; Stevenson, Mark A; Graves, Stephen; Rees, Robert; Stenos, John; Traub, Rebecca J

    2017-03-13

    Rickettsia felis and Rickettsia typhi are emerging arthropod-borne zoonoses causing fever and flu-like symptoms. Seroprevalence and risk factors associated with exposure to these organisms was explored in Australian veterinarians. One hundred and thirty-one veterinarians from across Australia were recruited to participate in a cross-sectional survey. Veterinarians provided a single blood sample and answered a questionnaire on potential risk factors influencing their exposure to R. felis and R. typhi. Indirect microimmunofluorescence antibody testing (IFAT) was used to identify evidence of serological exposure of the participants to R. felis and R. typhi. Results were analyzed and a logistical regression model performed to predict risk factors associated with seropositivity. In total, 16.0% of participants were seropositive to R. felis, 4.6% to R. typhi and 35.1% seropositive to both, where cross-reactivity of the IFAT between R. felis and R. typhi precluded a definitive diagnosis. Veterinarians residing within the south-eastern states of Victoria and Tasmania were at a higher risk of exposure to R. felis or generalised R. felis or R. typhi exposure. Older veterinarians and those that recommended flea treatment to their clients were found to be significantly protected from exposure. The high exposure to R. felis amongst veterinary professionals suggests that flea-borne spotted fever is an important cause of undifferentiated fever conditions that may not be adequately recognized in Australia.

  15. Development and validation of a quantitative real-time polymerase chain reaction assay specific for the detection of Rickettsia felis and not Rickettsia felis-like organisms.

    Science.gov (United States)

    Odhiambo, Antony M; Maina, Alice N; Taylor, Melissa L; Jiang, Ju; Richards, Allen L

    2014-07-01

    Human infections with Rickettsia felis have been reported worldwide. Recent studies have revealed the presence of many closely related but unique rickettsiae, referred to as Rickettsia felis-like organisms (RFLO), identified in various arthropods. Due to the recent discovery of the lack of specificity of earlier R. felis-specific assays, there has become a need to develop a new generation of R. felis-specific molecular assays that will differentiate R. felis not only from other rickettsiae but more importantly from other members of the R. felis genogroup that may not be pathogenic to humans. This new generation of assays is essential for determining the true risk for flea-borne spotted fever (FBSF) by surveying arthropod vectors/hosts. Because of the lack of specificity of previous assays developed to detect R. felis infections, prior surveys may have overestimated the prevalence of R. felis in arthropod vectors and thus the perceived risk of FBSF. We have developed a specific quantitative real-time polymerase chain reaction (qPCR) assay to detect R. felis (RfelB). Specificity of the assay was determined by testing it with a panel of 17 related Rickettsia species and 12 nonrickettsial bacterial DNA preparations. The RfelB qPCR assay was positive for R. felis DNA and negative for all of the 17 related Rickettsia species and 12 nonrickettsia bacterial DNA preparations. The limit of detection of the RfelB qPCR assay was determined to be two copies (two genoequivalents) per microliter of R. felis target ompB fragment-containing plasmid. Validation of the RfelB qPCR assay was accomplished by testing 83 previously sequence-confirmed R. felis and RFLOs containing DNA preparations from human and flea samples collected from different geographical locations around the world. This assay will be useful for rapid detection, identification, and enumeration of R. felis, an emerging human pathogen of worldwide importance, from both clinical and environmental samples.

  16. Detection of Rickettsia felis, Rickettsia typhi, Bartonella Species and Yersinia pestis in Fleas (Siphonaptera) from Africa.

    Science.gov (United States)

    Leulmi, Hamza; Socolovschi, Cristina; Laudisoit, Anne; Houemenou, Gualbert; Davoust, Bernard; Bitam, Idir; Raoult, Didier; Parola, Philippe

    2014-10-01

    Little is known about the presence/absence and prevalence of Rickettsia spp, Bartonella spp. and Yersinia pestis in domestic and urban flea populations in tropical and subtropical African countries. Fleas collected in Benin, the United Republic of Tanzania and the Democratic Republic of the Congo were investigated for the presence and identity of Rickettsia spp., Bartonella spp. and Yersinia pestis using two qPCR systems or qPCR and standard PCR. In Xenopsylla cheopis fleas collected from Cotonou (Benin), Rickettsia typhi was detected in 1% (2/199), and an uncultured Bartonella sp. was detected in 34.7% (69/199). In the Lushoto district (United Republic of Tanzania), R. typhi DNA was detected in 10% (2/20) of Xenopsylla brasiliensis, and Rickettsia felis was detected in 65% (13/20) of Ctenocephalides felis strongylus, 71.4% (5/7) of Ctenocephalides canis and 25% (5/20) of Ctenophthalmus calceatus calceatus. In the Democratic Republic of the Congo, R. felis was detected in 56.5% (13/23) of Ct. f. felis from Kinshasa, in 26.3% (10/38) of Ct. f. felis and 9% (1/11) of Leptopsylla aethiopica aethiopica from Ituri district and in 19.2% (5/26) of Ct. f. strongylus and 4.7% (1/21) of Echidnophaga gallinacea. Bartonella sp. was also detected in 36.3% (4/11) of L. a. aethiopica. Finally, in Ituri, Y. pestis DNA was detected in 3.8% (1/26) of Ct. f. strongylus and 10% (3/30) of Pulex irritans from the villages of Wanyale and Zaa. Most flea-borne infections are neglected diseases which should be monitored systematically in domestic rural and urban human populations to assess their epidemiological and clinical relevance. Finally, the presence of Y. pestis DNA in fleas captured in households was unexpected and raises a series of questions regarding the role of free fleas in the transmission of plague in rural Africa, especially in remote areas where the flea density in houses is high.

  17. Carry

    DEFF Research Database (Denmark)

    Koijen, Ralph S.J.; Moskowitz, Tobias J.; Heje Pedersen, Lasse

    that include global equities, global bonds, currencies, commodities, US Treasuries, credit, and equity index options. This predictability underlies the strong returns to "carry trades" that go long high-carry and short low-carry securities, applied almost exclusively to currencies, but shown here...

  18. Carry

    DEFF Research Database (Denmark)

    Koijen, Ralph S.J.; Moskowitz, Tobias; Pedersen, Lasse Heje

    2018-01-01

    -sectionally and in time series for a host of different asset classes, including global equities, global bonds, commodities, US Treasuries, credit, and options. Carry is not explained by known predictors of returns from these asset classes, and it captures many of these predictors, providing a unifying framework...... for return predictability. We reject a generalized version of Uncovered Interest Parity and the Expectations Hypothesis in favor of models with varying risk premia, in which carry strategies are commonly exposed to global recession, liquidity, and volatility risks, though none fully explains carry’s premium....

  19. Rickettsia Species in Ticks Removed from Humans in Istanbul, Turkey

    Science.gov (United States)

    Gargili, Aysen; Palomar, Ana M.; Midilli, Kenan; Portillo, Aránzazu; Kar, Sırrı

    2012-01-01

    Abstract A total of 167 ticks collected from humans in Istanbul (Turkey) in 2006 were screened for Rickettsia species, and nested PCRs targeting gltA and ompA rickettsial fragment genes were carried out. Rickettsia monacensis (51), R. aeschlimannii (8), R. conorii subsp. conorii (3), R. helvetica (2), R. raoultii (1), R. africae (1), R. felis (1), and other Rickettsia spp. (2), were detected. To our knowledge, these Rickettsia species (except R. conorii) had never been reported in ticks removed from humans in Turkey. The presence of R. africae also had not been previously described, either in Hyalomma ticks or in any European tick species. In addition, R. aeschlimannii and R. felis had not been found associated with Rhipicephalus bursa specimens. The presence of human pathogenic Rickettsia in ticks removed from humans provides information about the risk of tick-borne rickettsioses in Turkey. PMID:22925016

  20. Rickettsia felis in cat fleas, Ctenocephalides felis parasitizing opossums, San Bernardino County, California.

    Science.gov (United States)

    Abramowicz, K F; Wekesa, J W; Nwadike, C N; Zambrano, M L; Karpathy, S E; Cecil, D; Burns, J; Hu, R; Eremeeva, M E

    2012-12-01

    Los Angeles and Orange Counties are known endemic areas for murine typhus in California; however, no recent reports of flea-borne rickettsioses are known from adjacent San Bernardino County. Sixty-five opossums (Didelphis virginiana) were trapped in the suburban residential and industrial zones of the southwestern part of San Bernardino County in 2007. Sixty out of 65 opossums were infested with fleas, primarily cat fleas, Ctenocephalides felis (Bouché, 1835). The flea minimum infection rate with Rickettsia felis was 13.3% in pooled samples and the prevalence was 23.7% in single fleas, with two gltA genotypes detected. In spite of historic records of murine typhus in this area, no evidence for circulation of R. typhi in fleas was found during the present study. Factors contributing to the absence of R. typhi in these cat fleas in contrast to its presence in cat fleas from Orange and Los Angeles Counties are unknown and need to be investigated further in San Bernardino County. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

  1. Rickettsia and Bartonella species in fleas from Reunion Island.

    Science.gov (United States)

    Dieme, Constentin; Parola, Philippe; Guernier, Vanina; Lagadec, Erwan; Le Minter, Gildas; Balleydier, Elsa; Pagès, Frederic; Dellagi, Koussay; Tortosa, Pablo; Raoult, Didier; Socolovschi, Cristina

    2015-03-01

    Rickettsia felis, Rickettsia typhi, and Bartonella DNA was detected by molecular tools in 12% of Rattus rattus fleas (Xenopsylla species) collected from Reunion Island. One-third of the infested commensal rodents captured during 1 year carried at least one infected flea. As clinical signs of these zoonoses are non-specific, they are often misdiagnosed. © The American Society of Tropical Medicine and Hygiene.

  2. Absence of zoonotic Bartonella species in questing ticks: First detection of Bartonella clarridgeiae and Rickettsia felis in cat fleas in the Netherlands

    Directory of Open Access Journals (Sweden)

    Reimerink Johan R

    2011-04-01

    Full Text Available Abstract Background Awareness for flea- and tick-borne infections has grown in recent years and the range of microorganisms associated with these ectoparasites is rising. Bartonella henselae, the causative agent of Cat Scratch Disease, and other Bartonella species have been reported in fleas and ticks. The role of Ixodes ricinus ticks in the natural cycle of Bartonella spp. and the transmission of these bacteria to humans is unclear. Rickettsia spp. have also been reported from as well ticks as also from fleas. However, to date no flea-borne Rickettsia spp. were reported from the Netherlands. Here, the presence of Bartonellaceae and Rickettsiae in ectoparasites was investigated using molecular detection and identification on part of the gltA- and 16S rRNA-genes. Results The zoonotic Bartonella clarridgeiae and Rickettsia felis were detected for the first time in Dutch cat fleas. B. henselae was found in cat fleas and B. schoenbuchensis in ticks and keds feeding on deer. Two Bartonella species, previously identified in rodents, were found in wild mice and their fleas. However, none of these microorganisms were found in 1719 questing Ixodes ricinus ticks. Notably, the gltA gene amplified from DNA lysates of approximately 10% of the questing nymph and adult ticks was similar to that of an uncultured Bartonella-related species found in other hard tick species. The gltA gene of this Bartonella-related species was also detected in questing larvae for which a 16S rRNA gene PCR also tested positive for "Candidatus Midichloria mitochondrii". The gltA-gene of the Bartonella-related species found in I. ricinus may therefore be from this endosymbiont. Conclusions We conclude that the risk of acquiring Cat Scratch Disease or a related bartonellosis from questing ticks in the Netherlands is negligible. On the other hand fleas and deer keds are probable vectors for associated Bartonella species between animals and might also transmit Bartonella spp. to humans.

  3. Detection of Rickettsia massiliae/Bar29 and Rickettsia conorii in red foxes (Vulpes vulpes) and their Rhipicephalus sanguineus complex ticks.

    Science.gov (United States)

    Ortuño, Anna; Sanfeliu, Isabel; Nogueras, Mª Mercè; Pons, Imma; López-Claessens, Sonia; Castellà, Joaquim; Antón, Esperança; Segura, Ferran

    2018-03-01

    To determine the prevalence of exposure to Rickettsia massiliae/Bar29 and Rickettsia conorii in wild red foxes, we collected blood samples and ticks from 135 foxes shot in different game reserve areas in Catalonia. To detect SFG rickettsia in Rhipicephalus sanguineus complex ticks collected from the foxes, we used real-time polymerase chain reaction (PCR) to screen for ompA gene and a tick-borne bacteria flow chip technique based on multiplex PCR. Serum samples were positive for antibodies against spotted fever group (SFG) rickettsiae in 68 (50.3%). Molecular techniques identified R. massiliae in 107 ticks, R. aeschlimannii in 3 ticks, and R. slovaca in one tick; no R. conorii was identified in any of the ticks analyzed. We conclude that red foxes can carry ticks with SFG rickettsia. Copyright © 2018 Elsevier GmbH. All rights reserved.

  4. Detection of Bartonella tamiae, Coxiella burnetii and rickettsiae in arthropods and tissues from wild and domestic animals in northeastern Algeria.

    Science.gov (United States)

    Leulmi, Hamza; Aouadi, Atef; Bitam, Idir; Bessas, Amina; Benakhla, Ahmed; Raoult, Didier; Parola, Philippe

    2016-01-20

    In recent years, the scope and importance of emergent vector-borne diseases has increased dramatically. In Algeria, only limited information is currently available concerning the presence and prevalence of these zoonotic diseases. For this reason, we conducted a survey of hematophagous ectoparasites of domestic mammals and/or spleens of wild animals in El Tarf and Souk Ahras, Algeria. Using real-time PCR, standard PCR and sequencing, the presence of Bartonella spp., Rickettsia spp., Borrelia spp. and Coxiella burnetii was evaluated in 268/1626 ticks, 136 fleas, 11 Nycteribiidae flies and 16 spleens of domestic and/or wild animals from the El Tarf and Souk Ahras areas. For the first time in Algeria, Bartonella tamiae was detected in 12/19 (63.2%) Ixodes vespertilionis ticks, 8/11 (72.7%) Nycteribiidae spp. flies and in 6/10 (60%) bat spleens (Chiroptera spp.). DNA from Coxiella burnetii, the agent of Q fever, was also identified in 3/19 (15.8%) I. vespertilionis from bats. Rickettsia slovaca, the agent of tick-borne lymphadenopathy, was detected in 1/1 (100%) Haemaphysalis punctata and 2/3 (66.7%) Dermacentor marginatus ticks collected from two boars (Sus scrofa algira) respectively. Ri. massiliae, an agent of spotted fever, was detected in 38/94 (40.4%) Rhipicephalus sanguineus sensu lato collected from cattle, sheep, dogs, boars and jackals. DNA of Ri. aeschlimannii was detected in 6/20 (30%) Hyalomma anatolicum excavatum and 6/20 (30%) Hy. scupense from cattle. Finally, Ri. felis, an emerging rickettsial pathogen, was detected in 80/110 (72.7%) Archaeopsylla erinacei and 2/2 (100%) Ctenocephalides felis of hedgehogs (Atelerix algirus). In this study, we expanded knowledge about the repertoire of ticks and flea-borne bacteria present in ectoparasites and/or tissues of domestic and wild animals in Algeria.

  5. Dose-response model of murine typhus (Rickettsia typhi: time post inoculation and host age dependency analysis

    Directory of Open Access Journals (Sweden)

    Tamrakar Sushil B

    2012-03-01

    Full Text Available Abstract Background Rickettsia typhi (R. mooseri is the causative agent of murine typhus. It is one of the most widely distributed flea-borne diseases with a relatively mild febrile initial illness with six to 14 days of incubation period. The bacterium is gram negative and an obligate intracellular pathogen. The disease is transmitted to humans and vertebrate host through fleabites or via contact with infected feces. This paper develops dose-response models of different routes of exposure for typhus in rodents. Methods Data from published articles were analyzed using parametric dose-response relationship models. Dose-response relationships were fit to data using the method of maximum likelihood estimation (MLE. Results Dose-response models quantifying the effects of different ages of rats and time post inoculation in BALB/c mice were analyzed in the study. Both the adult rats (inoculated intradermally and newborn rats (inoculated subcutaneously were best fit by exponential models and both distributions could be described by a single dose-response relationship. The BALB/C mice inoculated subcutaneously were best fit by Beta-Poisson models. The time post inoculation analysis showed that there was a definite time and response relationship existed in this case. Conclusions Intradermally or subcutaneously inoculated rats (adult and newborn models suggest that less than 1 plaque-forming unit (PFU (1.33 to 0.38 in 95% confidence limits of the pathogen is enough to seroconvert 50% of the exposed population on average. For the BALB/c mouse time post inoculation model, an average dose of 0.28 plaque-forming units (PFU (0.75 to 0.11 in 95% confidence limits will seroconvert 50% of the exposed mice.

  6. Genome sequence of Rickettsia bellii illuminates the role of amoebae in gene exchanges between intracellular pathogens.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Ogata

    2006-05-01

    Full Text Available The recently sequenced Rickettsia felis genome revealed an unexpected plasmid carrying several genes usually associated with DNA transfer, suggesting that ancestral rickettsiae might have been endowed with a conjugation apparatus. Here we present the genome sequence of Rickettsia bellii, the earliest diverging species of known rickettsiae. The 1,552,076 base pair-long chromosome does not exhibit the colinearity observed between other rickettsia genomes, and encodes a complete set of putative conjugal DNA transfer genes most similar to homologues found in Protochlamydia amoebophila UWE25, an obligate symbiont of amoebae. The genome exhibits many other genes highly similar to homologues in intracellular bacteria of amoebae. We sought and observed sex pili-like cell surface appendages for R. bellii. We also found that R. bellii very efficiently multiplies in the nucleus of eukaryotic cells and survives in the phagocytic amoeba, Acanthamoeba polyphaga. These results suggest that amoeba-like ancestral protozoa could have served as a genetic "melting pot" where the ancestors of rickettsiae and other bacteria promiscuously exchanged genes, eventually leading to their adaptation to the intracellular lifestyle within eukaryotic cells.

  7. Integrated morphological and molecular identification of cat fleas (Ctenocephalides felis) and dog fleas (Ctenocephalides canis) vectoring Rickettsia felis in central Europe.

    Science.gov (United States)

    Lawrence, Andrea L; Hii, Sze-Fui; Jirsová, Dagmar; Panáková, Lucia; Ionică, Angela M; Gilchrist, Katrina; Modrý, David; Mihalca, Andrei D; Webb, Cameron E; Traub, Rebecca J; Šlapeta, Jan

    2015-06-15

    Fleas of the genus Ctenocephalides are the most common ectoparasites infesting dogs and cats world-wide. The species Ctenocephalides felis and Ctenocephalides canis are competent vectors for zoonotic pathogens such as Rickettsia felis and Bartonella spp. Improved knowledge on the diversity and phylogenetics of fleas is important for understanding flea-borne pathogen transmission cycles. Fleas infesting privately owned dogs and cats from the Czech Republic (n=97) and Romania (n=66) were subjected to morphological and molecular identification and phylogenetic analysis. There were a total of 59 (60.82%) cat fleas (Ctenocephalides felis felis), 30 (30.93%) dog fleas (Ctenocephalides canis), 7 (7.22%) European chicken fleas (Ceratophyllus gallinae) and 1 (1.03%) northern rat flea (Nosopsyllus fasciatus) collected in the Czech Republic. Both C. canis and C. felis felis were identified in Romania. Mitochondrial DNA sequencing at the cox1 gene on a cohort of 40 fleas revealed the cosmopolitan C. felis felis clade represented by cox1 haplotype 1 is present in the Czech Republic. A new C. felis felis clade from both the Czech Republic and Romania is also reported. A high proportion of C. canis was observed from dogs and cats in the current study and phylogeny revealed that C. canis forms a sister clade to the oriental cat flea Ctenocephalides orientis (syn. C. felis orientis). Out of 33 fleas tested, representing C. felis felis, C. canis and Ce. gallinae, 7 (21.2%) were positive for R. felis using diagnostic real-time PCR targeting the gltA gene and a conventional PCR targeting the ompB gene. No samples tested positive for Bartonella spp. using a diagnostic real-time PCR assay targeting ssrA gene. This study confirms high genetic diversity of C. felis felis globally and serves as a foundation to understand the implication for zoonotic disease carriage and transmission by the flea genus Ctenocephalides. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Rickettsiae in questing Ixodes ricinus ticks in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Venclíková, Kristýna; Rudolf, Ivo; Mendel, Jan; Betášová, Lenka; Hubálek, Zdeněk

    2014-01-01

    Roč. 5, č. 2 (2014), s. 135-138 ISSN 1877-959X Institutional support: RVO:68081766 Keywords : Ixodes ricinus * Anaplasma phagocytophilum * Rickettsia spp. * Rickettsia helvetica * Rickettsia monacensis * Candidatus Neoehrlichia mikurensis Subject RIV: EE - Microbiology, Virology Impact factor: 2.718, year: 2014

  9. Exotic Rickettsiae in Ixodes ricinus: fact or artifact?

    NARCIS (Netherlands)

    Tijsse-Klasen, E.; Fonville, M.; Overbeek, van L.S.; Reimerink, J.H.J.; Sprong, H.

    2010-01-01

    Several pathogenic Rickettsia species can be transmitted via Ixodes ricinus ticks to humans and animals. Surveys of I. ricinus for the presence of Rickettsiae using part of its 16S rRNA gene yield a plethora of new and different Rickettsia sequences. Interpreting these data is sometimes difficult

  10. Rickettsia bellii infecting Amblyomma sabanerae ticks in El Salvador.

    Science.gov (United States)

    Barbieri, Amália R M; Romero, Luis; Labruna, Marcelo B

    2012-07-01

    Four Amblyomma sabanerae ticks collected from a turtle (Kinosternon sp.) in San Miguel, El Salvador, were found by molecular analysis to be infected by Rickettsia bellii. We provide the first report of Rickettsia bellii in Central America, and the first report of a Rickettsia species in El Salvador.

  11. 'Candidatus Rickettsia mendelii', a novel basal group rickettsia detected in Ixodes ricinus ticks in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Hajdušková, Eva; Literák, I.; Papoušek, I.; Costa, F.B.; Nováková, M.; Labruna, M. B.; Zdražilová-Dubská, L.

    2016-01-01

    Roč. 7, č. 3 (2016), s. 482-486 ISSN 1877-959X Institutional support: RVO:60077344 Keywords : Rickettsiae * Candidatus Rickettsia mendelii * Ixodes ricinus * basal group rickettsiae * ticks * Czech Republic Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.230, year: 2016

  12. Rickettsia raoultii, the predominant Rickettsia found in Dermacentor silvarum ticks in China-Russia border areas.

    Science.gov (United States)

    Wen, Jing; Jiao, Dan; Wang, Jian-Hua; Yao, De-Hai; Liu, Zhi-Xiang; Zhao, Gang; Ju, Wen-Dong; Cheng, Cheng; Li, Yi-Jing; Sun, Yi

    2014-08-01

    Since the year 2000, clinical patterns resembling tick-borne rickettsioses have been noticed in China-Russia border areas. Epidemiological data regarding species of the aetiological agent, tick vector prevalence and distribution as well as incidence of human cases in the areas are still sparse to date. In order to identify Rickettsia species occurring in the areas, we investigated Dermacentor silvarum collected in the selected areas. Rickettsia raoultii was the predominant Rickettsia found in D. silvarum evident with ompA, ompB, gltA and 17 kDa protein genes. The Rickettsia prevalence in D. silvarum appeared to be 32.25 % with no sex difference. The results extend the common knowledge about the geographic distribution of R. raoultii and its candidate vector tick species, which suggest an emerged potential threat of human health in the areas.

  13. Spotted fever group rickettsiae in ticks of migratory birds in Romania.

    Science.gov (United States)

    Mărcuţan, Ioan-Daniel; Kalmár, Zsuzsa; Ionică, Angela Monica; D'Amico, Gianluca; Mihalca, Andrei Daniel; Vasile, Cozma; Sándor, Attila D

    2016-05-20

    Birds are important hosts and dispersers of parasitic arthropods and vector-borne zoonotic pathogens. Particularly migratory species may carry these parasites over long distances in short time periods. Migratory hotspots present ideal conditions to get a snapshot of parasite and pathogen diversity of birds migrating between continents. The aim of this study was to investigate the presence and diversity of Rickettsia spp. in ticks collected from birds at a migratory hot-spot in the Danube Delta, Romania, eastern Europe. DNA was extracted from ticks that were collected from migratory birds in the Danube Delta during migratory seasons in 2011-2012. Two 360 bp  fragments of the 16S ribosomal RNA gene and a 381 bp  fragment Gene gltA were PCR amplified and analyzed by sequence analysis (performed at Macrogen Europe, Amsterdam, The Netherlands). Nucleotide sequences were compared to reference sequences available in the GenBank database, using Basic Local Alignment Search Tool. Four hundred ticks of four different species were found on 11 bird species. The prevalence of Rickettsia spp. infection was 14 % (56/400, CI: 11.7-29.1), with significantly more nymphs hosting rickettsial infection compared to larvae (48 vs 7; P birds migrating through eastern Europe may carry ticks infected with a high diversity of rickettsial pathogens, with four Rickettsia spp. recorded. Migratory direction was important for pathogen burden, with seasonal differences in the occurrence of individual Rickettsia species. Here we report the first individual records of different Rickettsia spp. in H. concinna (R. monacensis), I. arboricola (R. helvetica, R. massiliae) and I. redikorzevi (R. helvetica) and also the first geographical record of occurrence of R. massiliae in Romania, representing the easternmost observation on the continent.

  14. 'Candidatus Rickettsia nicoyana': A novel Rickettsia species isolated from Ornithodoros knoxjonesi in Costa Rica.

    Science.gov (United States)

    Moreira-Soto, Rolando D; Moreira-Soto, Andrés; Corrales-Aguilar, Eugenia; Calderón-Arguedas, Ólger; Troyo, Adriana

    2017-06-01

    Rickettsiae are intracellular bacteria commonly associated with hematophagous arthropods. Most of them have been described in hard ticks, but some have been found in soft ticks. Here we report the detection and isolation of a new Rickettsia from Ornithodoros knoxjonesi larvae collected from Balantiopteryx plicata (Emballonuridae) in Nicoya, Costa Rica. Two ticks were processed to detect Rickettsia spp. genes gltA, ompA, ompB, and htrA by PCR. Part of the macerate was also inoculated into Vero E6 and C6/36 cell lines, and cells were evaluated by Giménez stain, indirect immunofluorescence assay (IFA), and PCR. Both ticks were positive by PCR and rickettsial growth was successful in Vero E6 cells. Amplification and sequencing of near full length rrs, gltA, sca4 genes, and fragments of ompA and ompB showed that the Rickettsia sp. was different from described species. The highest homologies were with 'Candidatus Rickettsia wissemanii' and Rickettsia peacockii: 99.70% (1321/1325) with both sequences for rrs, 99.58% (1172/1177) and 99.76% (1246/1249) for gltA, 99.26% with both sequences (2948/2970 and 2957/2979) for sca4, 98.78% (485/491) and 98.39% (2069/2115) for ompA, and 98.58 (1453/1474) and 98.92% (1459/1475) for ompB; respectively. Bat blood, spleen, liver, and lung samples analyzed for Rickettsia detection were negative. Results demonstrate that the Rickettsia isolated from O. knoxjonesi is probably an undescribed species that belongs to the spotted fever group, for which 'Candidatus Rickettsia nicoyana' is proposed. Considering that B. plicata inhabits areas where contact with humans may occur and that human parasitism by Ornithodoros has been reported in the country, it will be important to continue with the characterization of this species and its pathogenic potential. Copyright © 2017 Elsevier GmbH. All rights reserved.

  15. Genotypic and biological characteristics of non-identified strain of spotted fever group rickettsiae isolated in Crimea.

    Science.gov (United States)

    Balayeva, N M; Demkin, V V; Rydkina, E B; Ignatovich, V F; Artemiev, M I; Lichoded LYa; Genig, V A

    1993-12-01

    A strain of rickettsiae, designated Crimea-108, was isolated from ticks Dermacentor marginatus in the Crimea in 1977. Its immunobiological characteristics involve low pathogenicity for experimental animals, moderate infectivity for chick embryos, and antigenic relatedness to spotted fever group (SFG) rickettsiae (R. sibirica, R. conorii, R. akari), especially to R. sibirica. The genotypic characterization of the strain Crimea-108 was carried out in comparison with SFG and typhus group rickettsiae by using restriction fragment length polymorphism (RFLP) analysis and DNA-probe hybridization. The marked similarity was detected between DNA restriction patterns of the strains Crimea-108, R. sibirica and R. conorii, but each of them besides comigrating fragments had specific ones. Genotypic analysis of the strain Crimea-108, the SFG and typhus group rickettsiae by three independent DNA probes, based on R. prowazekii DNA, gave unique hybridization patterns for the Crimea-108 strain with all probes. The obtained data show that the Crimea-108 isolate does not belong to the species of R. sibirica, R. conorii, R. akari. The strain Crimea-108 is a novel strain of SFG rickettsiae for the Crimea region.

  16. Co-infection of Borrelia burgdorferi sensu lato and Rickettsia species in ticks and in an erythema migrans patient.

    Science.gov (United States)

    Tijsse-Klasen, Ellen; Sprong, Hein; Pandak, Nenad

    2013-12-10

    Lyme borreliosis is the most prevalent tick-borne disease in Europe. Ixodes ricinus also carries other pathogenic bacteria, but corresponding human diseases are rarely reported. Here, we compared the exposure to Rickettsia helvetica and Rickettsia monacensis with that to Lyme borreliosis spirochetes. We assumed that their exposure corresponds to their infection rate in questing I. ricinus. Three Rickettsia species were detected in ticks with a total prevalence of 7.9%, of which the majority was R. helvetica (78%) and R. monacensis (21%). From the same geographic area, skin biopsies of erythema migrans patients were investigated for possible co-infections with Rickettsia spp.. Forty-seven out of 67 skin biopsies were PCR positive for Borrelia burgdorferi s.l. and one sample was positive for R. monacensis. The Borrelia genospecies from the R. monacensis positive patient was identified as Borrelia afzelii. The patient did not show any symptoms associated with rickettsiosis. Co-infections of I. ricinus with Rickettsia spp. and B. burgdorferi s.l. were as high as expected from the individual prevalence of both pathogens. Co-infection rate in erythema migrans patients corresponded well with tick infection rates. To our knowledge, this is the first reported co-infection of B. afzelii and R. monacensis.

  17. Green Fluorescent Protein as a Marker in Rickettsia typhi Transformation

    OpenAIRE

    Troyer, Jill Michelle; Radulovic, Suzana; Azad, Abdu F.

    1999-01-01

    Transformation of rickettsiae is a recent accomplishment, but utility of this technique is limited due to the paucity of selectable markers suitable for use in this intracellular pathogen. We chose a green fluorescent protein variant optimized for fluorescence under UV lights (GFPUV) as a fluorometric marker and transformed Rickettsia typhi with an rpoB-GFPUV fusion construct. The rickettsiae were subsequently grown in Vero cells, and cultures were screened by PCR and restriction fragment len...

  18. Rickettsia conorii transcriptional response within inoculation eschar.

    Directory of Open Access Journals (Sweden)

    Patricia Renesto

    Full Text Available BACKGROUND: Rickettsia conorii, the causative agent of the Mediterranean spotted fever, is transmitted to humans by the bite of infected ticks Rhipicephalus sanguineus. The skin thus constitutes an important barrier for the entry and propagation of R. conorii. Given this, analysis of the survival strategies used by the bacterium within infected skin is critical for our understanding of rickettsiosis. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the first genome-wide analysis of R. conorii gene expression from infected human skin biopsies. Our data showed that R. conorii exhibited a striking transcript signature that is remarkably conserved across patients, regardless of genotype. The expression profiles obtained using custom Agilent microarrays were validated by quantitative RT-PCR. Within eschars, the amount of detected R. conorii transcripts was of 55%, this value being of 74% for bacteria grown in Vero cells. In such infected host tissues, approximately 15% (n = 211 of the total predicted R. conorii ORFs appeared differentially expressed compared to bacteria grown in standard laboratory conditions. These genes are mostly down-regulated and encode proteins essential for bacterial replication. Some of the strategies displayed by rickettsiae to overcome the host defense barriers, thus avoiding killing, were also pointed out. The observed up-regulation of rickettsial genes associated with DNA repair is likely to correspond to a DNA-damaging agent enriched environment generated by the host cells to eradicate the pathogens. Survival of R. conorii within eschars also involves adaptation to osmotic stress, changes in cell surface proteins and up-regulation of some virulence factors. Interestingly, in contrast to down-regulated transcripts, we noticed that up-regulated ones rather exhibit a small nucleotide size, most of them being exclusive for the spotted fever group rickettsiae. CONCLUSION/SIGNIFICANCE: Because eschar is a site for rickettsial

  19. 21 CFR 866.3500 - Rickettsia serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rickettsia serological reagents. 866.3500 Section 866.3500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... the diagnosis of diseases caused by virus-like bacteria belonging to the genus Rickettsiae and...

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

    Science.gov (United States)

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

    2016-03-01

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

  1. Detection of Rickettsia helvetica in Ixodes ricinus infesting wild and domestic animals and in a botfly larva (Cephenemyia stimulator) infesting roe deer in Germany.

    Science.gov (United States)

    Scheid, Patrick; Speck, Stephanie; Schwarzenberger, Rafael; Litzinger, Mark; Balczun, Carsten; Dobler, Gerhard

    2016-10-01

    Ixodes ricinus is a well-known vector of different human pathogens including Rickettsia helvetica. The role of wild mammals in the distribution and probable maintenance of Rickettsia in nature is still to be determined. We therefore investigated various parasites from different wild mammals as well as companion animals for the presence of Rickettsia. A total of 606 I. ricinus, 38 Cephenemyia stimulator (botfly larvae), one Dermacentor reticulatus, 24 Haematopinus suis (hog lice) and 30 Lipoptena cervi (deer flies) were collected from free-ranging animals during seasonal hunting, and from companion animals. Sample sites included hunting leases at three main sampling areas and five additional areas in West and Central Germany. All collected parasites were screened for Rickettsia spp. and I. ricinus were investigated for tick-borne encephalitis virus (TBEV) in addition. While no TBEV was detected, the minimum infection rate (MIR) of I. ricinus with Rickettsia was 4.1% referring to all sampling sites and up to 6.9% at the main sampling site in Koblenz area. Sequencing of a fragment of the ompB gene identified R. helvetica. Approximately one third (29.5%) of the animals carried Rickettsia-positive ticks and the MIR in ticks infesting wild mammals ranged from 4.1% (roe deer) to 9.5%. These data affirm the widespread distribution of R. helvetica in Germany. One botfly larva from roe deer also harboured R. helvetica. Botfly larvae are obligate parasites of the nasal cavity, pharynx and throat of cervids and feed on cell fragments and blood. Based on this one might hypothesise that R. helvetica likely induces rickettsemia in cervids thus possibly contributing to maintenance and distribution of this rickettsia in the field. Copyright © 2016 Elsevier GmbH. All rights reserved.

  2. Rickettsia felis in Ctenocephalides felis from Guatemala and Costa Rica.

    Science.gov (United States)

    Troyo, Adriana; Álvarez, Danilo; Taylor, Lizeth; Abdalla, Gabriela; Calderón-Arguedas, Ólger; Zambrano, Maria L; Dasch, Gregory A; Lindblade, Kim; Hun, Laya; Eremeeva, Marina E; Estévez, Alejandra

    2012-06-01

    Rickettsia felis is an emerging human pathogen associated primarily with the cat flea Ctenocephalides felis. In this study, we investigated the presence of Rickettsia felis in C. felis from Guatemala and Costa Rica. Ctenocephalides felis were collected directly from dogs and cats, and analyzed by polymerase chain reaction for Rickettsia-specific fragments of 17-kDa protein, OmpA, and citrate synthase genes. Rickettsia DNA was detected in 64% (55 of 86) and 58% (47 of 81) of flea pools in Guatemala and Costa Rica, respectively. Sequencing of gltA fragments identified R. felis genotype URRWXCal(2) in samples from both countries, and genotype Rf2125 in Costa Rica. This is the first report of R. felis in Guatemala and of genotype Rf2125 in Costa Rica. The extensive presence of this pathogen in countries of Central America stresses the need for increased awareness and diagnosis.

  3. Zoonotic surveillance for rickettsiae in domestic animals in Kenya.

    Science.gov (United States)

    Mutai, Beth K; Wainaina, James M; Magiri, Charles G; Nganga, Joseph K; Ithondeka, Peter M; Njagi, Obadiah N; Jiang, Ju; Richards, Allen L; Waitumbi, John N

    2013-06-01

    Abstract Rickettsiae are obligate intracellular bacteria that cause zoonotic and human diseases. Arthropod vectors, such as fleas, mites, ticks, and lice, transmit rickettsiae to vertebrates during blood meals. In humans, the disease can be life threatening. This study was conducted amidst rising reports of rickettsioses among travelers to Kenya. Ticks and whole blood were collected from domestic animals presented for slaughter at major slaughterhouses in Nairobi and Mombasa that receive animals from nearly all counties in the country. Blood samples and ticks were collected from 1019 cattle, 379 goats, and 299 sheep and were screened for rickettsiae by a quantitative PCR (qPCR) assay (Rick17b) using primers and probe that target the genus-specific 17-kD gene (htrA). The ticks were identified using standard taxonomic keys. All Rick17b-positive tick DNA samples were amplified and sequenced with primers sets that target rickettsial outer membrane protein genes (ompA and ompB) and the citrate-synthase encoding gene (gltA). Using the Rick17b qPCR, rickettsial infections in domestic animals were found in 25/32 counties sampled (78.1% prevalence). Infection rates were comparable in cattle (16.3%) and sheep (15.1%) but were lower in goats (7.1%). Of the 596 ticks collected, 139 had rickettsiae (23.3%), and the detection rates were highest in Amblyomma (62.3%; n=104), then Rhipicephalus (45.5%; n=120), Hyalomma (35.9%; n=28), and Boophilus (34.9%; n=30). Following sequencing, 104 out of the 139 Rick17b-positive tick DNA had good reverse and forward sequences for the 3 target genes. On querying GenBank with the generated consensus sequences, homologies of 92-100% for the following spotted fever group (SFG) rickettsiae were identified: Rickettsia africae (93.%, n=97), Rickettsia aeschlimannii (1.9%, n=2), Rickettsia mongolotimonae (0.96%, n=1), Rickettsia conorii subsp. israelensis (0.96%, n=1), Candidatus Rickettsia kulagini (0.96% n=1), and Rickettsia spp. (1.9% n=2). In

  4. Detection of Rickettsia in Rhipicephalus sanguineus Ticks and Ctenocephalides felis Fleas from Southeastern Tunisia by Reverse Line Blot Assay

    Science.gov (United States)

    Khrouf, Fatma; M'Ghirbi, Youmna; Znazen, Abir; Ben Jemaa, Mounir; Hammami, Adnene

    2014-01-01

    Ticks (n = 663) and fleas (n = 470) collected from domestic animals from southeastern Tunisia were screened for Rickettsia infection using reverse line blot assay. Evidence of spotted fever group Rickettsia was obtained. We detected Rickettsia felis in fleas, Rickettsia massiliae Bar 29 and the Rickettsia conorii Israeli spotted fever strain in ticks, and Rickettsia conorii subsp. conorii and Rickettsia spp. in both arthropods. The sensitivity of the adopted technique allowed the identification of a new association between fleas and R. conorii subsp. conorii species. The presence of these vector-borne Rickettsia infections should be considered when diagnosing this disease in humans in Tunisia. PMID:24226919

  5. Development of shuttle vectors for transformation of diverse Rickettsia species.

    Directory of Open Access Journals (Sweden)

    Nicole Y Burkhardt

    Full Text Available Plasmids have been identified in most species of Rickettsia examined, with some species maintaining multiple different plasmids. Three distinct plasmids were demonstrated in Rickettsia amblyommii AaR/SC by Southern analysis using plasmid specific probes. Copy numbers of pRAM18, pRAM23 and pRAM32 per chromosome in AaR/SC were estimated by real-time PCR to be 2.0, 1.9 and 1.3 respectively. Cloning and sequencing of R. amblyommii AaR/SC plasmids provided an opportunity to develop shuttle vectors for transformation of rickettsiae. A selection cassette encoding rifampin resistance and a fluorescent marker was inserted into pRAM18 yielding a 27.6 kbp recombinant plasmid, pRAM18/Rif/GFPuv. Electroporation of Rickettsia parkeri and Rickettsia bellii with pRAM18/Rif/GFPuv yielded GFPuv-expressing rickettsiae within 2 weeks. Smaller vectors, pRAM18dRG, pRAM18dRGA and pRAM32dRGA each bearing the same selection cassette, were made by moving the parA and dnaA-like genes from pRAM18 or pRAM32 into a vector backbone. R. bellii maintained the highest numbers of pRAM18dRGA (13.3 - 28.1 copies, and R. parkeri, Rickettsia monacensis and Rickettsia montanensis contained 9.9, 5.5 and 7.5 copies respectively. The same species transformed with pRAM32dRGA maintained 2.6, 2.5, 3.2 and 3.6 copies. pRM, the plasmid native to R. monacensis, was still present in shuttle vector transformed R. monacensis at a level similar to that found in wild type R. monacensis after 15 subcultures. Stable transformation of diverse rickettsiae was achieved with a shuttle vector system based on R. amblyommii plasmids pRAM18 and pRAM32, providing a new research tool that will greatly facilitate genetic and biological studies of rickettsiae.

  6. Detection of an undescribed Rickettsia sp. in Ixodes boliviensis from Costa Rica.

    Science.gov (United States)

    Troyo, Adriana; Moreira-Soto, Andrés; Carranza, Marco; Calderón-Arguedas, Olger; Hun, Laya; Taylor, Lizeth

    2014-10-01

    Ixodes boliviensis is a tick of carnivores that is common on domestic dogs. The only Rickettsia that has been detected previously in this species is 'Candidatus Rickettsia andeanae'. We report the detection of an undescribed Rickettsia sp., named strain IbR/CRC, in I. boliviensis collected from dogs in Costa Rica. Analyses of gltA, ompA, and htrA partial sequences place Rickettsia sp. strain IbR/CRC in the group of R. monacensis, also close to an endosymbiont of Ixodes scapularis and other undescribed rickettsiae. It was not possible to isolate Rickettsia sp. strain IbR/CRC in Vero E6 or C6/36 cell lines. Isolation and further characterization of Rickettsia sp. strain IbR/CRC and the other undescribed rickettsiae are required to determine their taxonomic status and pathogenic potential. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. Diversity of rickettsiae in a rural community in northern California.

    Science.gov (United States)

    Stephenson, Nicole; Blaney, Alexandra; Clifford, Deana; Gabriel, Mourad; Wengert, Greta; Foley, Patrick; Brown, Richard N; Higley, Mark; Buckenberger-Mantovani, Sarah; Foley, Janet

    2017-06-01

    Far northern California forests are highly biodiverse in wildlife reservoirs and arthropod vectors that may propagate rickettsial pathogens in nature. The proximity of small rural communities to these forests puts people and domestic animals at risk of vector-borne infection due to spillover from wildlife. The current study was conducted to document exposure to rickettsial pathogens in people and domestic animals in a rural community, and identify which rickettsiae are present in sylvatic and peri-domestic environments near this community. Blood samples from people, domestic animals (dogs, cats, and horses) and wild carnivores were tested for Rickettsia spp. antibodies and DNA (people and domestic animals only) by serology and real time (RT)-PCR, respectively. Ectoparasites were collected from dogs, wild carnivores and from vegetation by flagging, and tested for Rickettsia spp. DNA by RT-PCR. DNA sequencing of the rickettsial 17kDa protein gene or the ompA gene was used for species identification. Despite a seroprevalence of 3% in people, 42% in dogs, 79% in cats, 33% in gray foxes, and 83% in bobcats, RT-PCR on blood was consistently negative, likely because the sensitivity of this test is low, as Rickettsia spp. do not often circulate in high numbers in the blood. Rickettsia spp. DNA was found in four flea species collected from bobcats and Ctenocephalides felis collected from domestic dogs. All amplicons sequenced from fleas were R. felis. Ixodes pacificus collected by flagging were commonly infected with a Rickettsia sp. endosymbiont. Rickettsia rhipicephali DNA was found in Dermacentor variabilis from dogs, black bears, a gray fox, and a D. occidentalis collected by flagging. Dermacentor variabilis from dogs and black bears also contained R. montanensis DNA. Multiple Rickettsia spp. (including species with zoonotic and pathogenic potential) were found among human biting arthropod vectors of both wild and domestic carnivores and on flags. Knowledge of the

  8. Molecular Evidence of Different Rickettsia Species in Villeta, Colombia.

    Science.gov (United States)

    Faccini-Martínez, Álvaro A; Ramírez-Hernández, Alejandro; Forero-Becerra, Elkin; Cortés-Vecino, Jesús A; Escandón, Patricia; Rodas, Juan D; Palomar, Ana M; Portillo, Aránzazu; Oteo, José A; Hidalgo, Marylin

    2016-02-01

    The aim of this work was to detect and identify Rickettsia species in ticks collected in rural areas of Villeta, Colombia. Tick specimens were collected from domestic animals and walls of houses in five rural villages of Villeta town and from humans in Naranjal village (same town). Moreover, a flea collected from the same area was also processed. DNA was extracted and tested by conventional, semi-nested, and nested PCR reactions targeting rickettsial genes. In the ticks collected from humans from Naranjal village, a nymph of Amblyomma cajennense sensu lato was amplified using primers for ompA and sequenced (100% identity with "Candidatus Rickettsia amblyommii"). Last, three amplicons from the Ctenocephalides felis flea, corresponding to gltA, ompB, and 16S rRNA genes, showed high identity with R. felis (98.5%, 97.3%, and 99.2%, respectively) and "Candidatus Rickettsia asemboensis" (99.7% and 100%, respectively). To our knowledge, these results correspond to the first molecular detection in Colombia of "Candidatus Rickettsia amblyommii" and "Ca. Rickettsia asemboensis" in fleas.

  9. THE ANTIGENIC RELATIONSHIP BETWEEN PROTEUS X-19 AND TYPHUS RICKETTSIA

    Science.gov (United States)

    Castaneda, M. Ruiz

    1934-01-01

    A soluble specific substance was isolated from Mexican typhus Rickettsia which gave, with Proteus X-19 antiserum and typhus human serum, the same precipitation reactions as the polysaccharides extracted from B. proteus OX-19. The soluble specific substance extracted from Rickettsia and Proteus OX-19 is likely to be of a polysaccharide nature owing to the strong Molisch reactions obtained with such extracts, the heat stability and the negative protein reactions (biuret). Since, however, it still contains 7 per cent nitrogen, this is not certain. In the antigenic composition of both Proteus X-19 and typhus Rickettsia there is a common soluble specific factor which is responsible for the Weil-Felix reaction. PMID:19870282

  10. Novos relatos de carrapatos infectados por Rickettsia bellii no Brasil

    OpenAIRE

    Francisco Borges Costa; Amália Regina Barbieri; Matias pablo Juan Szabó; Vanessa Nascimento Ramos; Ubiratan Piovezan; Marcelo Bahia Labruna

    2017-01-01

    O presente trabalho investigou a ocorrência de infecção por Rickettsia em carrapatos coletados em animais selvagens de duas áreas do Brasil. Carrapatos da espécie Amblyomma dubitatum foram coletados de uma capivara (Hydrochoerus hydrochaeris) no município de Guarda-Mor, Minas Gerais, enquanto exemplares da espécie Amblyomma pseudoconcolor foram coletados de um tatu-peba (Euphractus sexcinctus) do município de Corumbá, Mato Grosso do Sul. Tentativas para isolar Rickettsia em cultura de células...

  11. 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.

  12. Serological evidence of infection with Rickettsia typhi among ...

    African Journals Online (AJOL)

    Poor sanitary conditions/personal hygiene, history of fleabite/contact with animals and overcrowding in the prison were found to be significantly associated with the infection in this population (p< 0.05). Our data seem to reveal the presence of Rickettsia typhi among prison inmates in Jos. Conclusion: Rodent and flea control ...

  13. Direct evidence of Rickettsia typhi infection in Rhipicephalus ...

    African Journals Online (AJOL)

    These studies remarks that in addition to rats, other animals like cats, opossums and dogs could be implied in the transmission of Rickettsia typhi as infected fleas obtained from serologically positive animals have been detected in samples from endemic areas. In Mexico, the higher number of murine typhus cases have ...

  14. Cat fleas (Ctenocephalides felis) from cats and dogs in New Zealand: Molecular characterisation, presence of Rickettsia felis and Bartonella clarridgeiae and comparison with Australia.

    Science.gov (United States)

    Chandra, Shona; Forsyth, Maureen; Lawrence, Andrea L; Emery, David; Šlapeta, Jan

    2017-01-30

    The cat flea (Ctenocephalides felis) is the most common flea species parasitising both domestic cats and dogs globally. Fleas are known vectors of zoonotic pathogens such as vector borne Rickettsia and Bartonella. This study compared cat fleas from domestic cats and dogs in New Zealand's North and South Islands to Australian cat fleas, using the mitochondrial DNA (mtDNA) marker, cytochrome c oxidase subunit I and II (cox1, cox2). We assessed the prevalence of Rickettsia and Bartonella using genus specific multiplexed real-time PCR assays. Morphological identification confirmed that the cat flea (C. felis) is the most common flea in New Zealand. The examined fleas (n=43) at cox1 locus revealed six closely related C. felis haplotypes (inter-haplotype distance 1.1%) across New Zealand. The New Zealand C. felis haplotypes were identical or near identical with haplotypes from southern Australia demonstrating common dispersal of haplotype lineage across both the geographical (Tasman Sea) and climate scale. New Zealand cat fleas carried Rickettsia felis (5.3%) and Bartonella clarridgeiae (18.4%). To understand the capability of C. felis to vector zoonotic pathogens, we determined flea cox1 and cox2 haplotype diversity with the tandem multiplexed real-time PCR and sequencing for Bartonella and Rickettsia. This enabled us to demonstrate highly similar cat fleas on cat and dog populations across Australia and New Zealand. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Plant-mediated horizontal transmission of Rickettsia endosymbiont between different whitefly species.

    Science.gov (United States)

    Li, Yi-Han; Ahmed, Muhammad Z; Li, Shao-Jian; Lv, Ning; Shi, Pei-Qiong; Chen, Xiao-Sheng; Qiu, Bao-Li

    2017-12-01

    A growing number of studies have revealed the presence of closely related endosymbionts in phylogenetically distant arthropods, indicating horizontal transmission of these bacteria. Here we investigated the interspecific horizontal transmission of Rickettsia between two globally invasive whitefly species, Bemisia tabaci MEAM1 and B. tabaci MED, via cotton plants. We found both scattered and confined distribution patterns of Rickettsia in these whiteflies. After entering cotton leaves, Rickettsia was restricted to the leaf phloem vessels and could be taken up by both species of the Rickettsia-free whitefly adults, but only the scattered pattern was observed in the recipient whiteflies. Both the relative quantity of Rickettsia and the efficiency of transmitting Rickettsia into cotton leaves were significantly higher in MEAM1 females than in MED females. The retention time of Rickettsia transmitted from MEAM1 into cotton leaves was at least 5 days longer than that of MED. Phylogenetic analysis based on 16S rRNA and gltA genes confirmed that the Rickettsia extracted from the donor MEAM1, the cotton leaves, the recipient MEAM1 and the recipient MED were all identical. We conclude that cotton plants can mediate horizontal transmission of Rickettsia between different insect species, and that the transmission dynamics of Rickettsia vary with different host whitefly species. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Carrying Capacity

    DEFF Research Database (Denmark)

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive....../cities. Four different sectors (water, food production, waste, and forests) were selected as core areas for decentralised spatial planning. Indicators for SCC and ACC were identified and assessed with regard to relevance and quantifiability. For each of the indicators selected, a legal threshold or guiding...... was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive carrying capacity (SCC) and assimilative...

  17. 'Candidatus Rickettsia mendelii', a novel basal group rickettsia detected in Ixodes ricinus ticks in the Czech Republic.

    Science.gov (United States)

    Hajduskova, Eva; Literak, Ivan; Papousek, Ivo; Costa, Francisco B; Novakova, Marketa; Labruna, Marcelo B; Zdrazilova-Dubska, Lenka

    2016-04-01

    A novel rickettsial sequence in the citrate synthase gltA gene indicating a novel Rickettsia species has been detected in 7 out of 4524 Ixodes ricinus ticks examined within several surveys performed in the Czech Republic from 2005 to 2009. This new Candidatus Rickettsia sp. sequence has been found in 2 nymphs feeding on wild birds (Luscinia megarhynchos and Erithacus rubecula), in a male tick from vegetation, and 4 ticks feeding on a dog (3 males, 1 female tick). Portions of the ompA, ompB, sca4, and htrA genes were not amplifiable in these samples. A maximum likelihood tree of rickettsiae based on comparisons of partial amino acid sequences of citrate synthase and nucleotide sequences of 16S rDNA genes and phylogenetic analysis revealed a basal position of the novel species in the proximity of R. bellii and R. canadensis. The novel species has been named 'Candidatus Rickettsia mendelii' after the founder of genetics, Gregor Mendel. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Urban family cluster of spotted fever rickettsiosis linked to Rhipicephalus sanguineus infected with Rickettsia conorii subsp. caspia and Rickettsia massiliae.

    Science.gov (United States)

    Renvoisé, Aurélie; Delaunay, Pascal; Blanchouin, Elea; Cannavo, Isabelle; Cua, Eric; Socolovschi, Cristina; Parola, Philippe; Raoult, Didier

    2012-12-01

    Here, we report an epidemiological and entomological investigation of a cluster of cases of spotted fever group (SFG) rickettsiosis occurring in southern France. A family of 3 (husband, wife, and their son) presented with symptoms compatible with SFG rickettsiosis. For 2 patients, serum samples presented increased levels of IgM and IgG for SFG Rickettsia. The patients' home was investigated, and Rhipicephalus sanguineus ticks were collected from the floor from behind the furniture. Of 22 ticks collected, 20 tested positive for Rickettsia. As Rh. sanguineus serves as a vector for both Rickettsia conorii and Ri. massiliae in southern France, all Rh. sanguineus isolates were tested by real-time PCR and conventional PCR to detect the 2 species. Nine ticks tested positive for Ri. conorii subsp. caspia (marking the first documentation of this subspecies in France), 7 tested positive for Ri. massiliae, and 4 tested positive for both rickettsiae. This study is the first report of coinfection of Rh. sanguineus ticks with Ri. conorii and Ri. massiliae in southern France. Copyright © 2012 Elsevier GmbH. All rights reserved.

  19. Seroprevalence of Rickettsia spp. in Equids and Molecular Detection of 'Candidatus Rickettsia amblyommii' in Amblyomma cajennense Sensu Lato Ticks From the Pantanal Region of Mato Grosso, Brazil.

    Science.gov (United States)

    Alves, Alvair Da S; Melo, Andréia L T; Amorim, Marcus V; Borges, Alice M C M; Gaíva E Silva, Lucas; Martins, Thiago F; Labruna, Marcelo B; Aguiar, Daniel M; Pacheco, Richard C

    2014-11-01

    The aim of the study was to evaluate exposure of equids to rickettsial agents (Rickettsia rickettsii, Rickettsia parkeri, 'Candidatus Rickettsia amblyommii', Rickettsia rhipicephali, and Rickettsia bellii) and rickettsial infection in ticks of a Pantanal region of Brazil. Sera of 547 equids (500 horses and 47 donkeys) were evaluated by indirect immunofluorescence assay. In total, 665 adults and 106 nymphal pools of Amblyomma cajennense F. sensu lato, 10 Dermacentor nitens Neumann ticks, and 88 larval pools of Amblyomma sp. were tested by polymerase chain reaction (PCR). Overall, 337 (61.6%) equids were reactive (titer ≥64) to at least one antigen of Rickettsia spp. The prevalence values for Rickettsia were 66%, and the highest endpoint titers were observed for 'Ca. R. amblyommii'. By PCR 3 (0.45%) A. cajennense s.l. females were positive for 'Ca. R. amblyommii'. Minimum infection rates of 0.75% for nymphs and 0.34% for larvae were calculated. Positive samples of ticks have had a fragment of the 16S mitochondrial rRNA gene sequenced and sequences showed 99% identity to Amblyomma sculptum Berlese. This study reports a wide exposure of equids to Rickettsia agents, and PCR evidence of infection with 'Ca. R. amblyommii', for the first time, in A. sculptum. © 2014 Entomological Society of America.

  20. Dissemination of spotted fever rickettsia agents in Europe by migrating birds.

    Science.gov (United States)

    Elfving, Karin; Olsen, Björn; Bergström, Sven; Waldenström, Jonas; Lundkvist, Ake; Sjöstedt, Anders; Mejlon, Hans; Nilsson, Kenneth

    2010-01-05

    Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp.IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases.

  1. 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.

  2. Propagation of Arthropod-Borne Rickettsia spp. in Two Mosquito Cell Lines▿

    OpenAIRE

    Sakamoto, Joyce M.; Azad, Abdu F.

    2007-01-01

    Rickettsiae are obligate intracellular alphaproteobacteria that include pathogenic species in the spotted fever, typhus, and transitional groups. The development of a standardized cell line in which diverse rickettsiae can be grown and compared would be highly advantageous to investigate the differences among and between pathogenic and nonpathogenic species of rickettsiae. Although several rickettsial species have been grown in tick cells, tick cells are more difficult to maintain and they gr...

  3. Serological evidence of Rickettsia infections in forestry rangers in north-eastern Italy.

    Science.gov (United States)

    Cinco, M; Luzzati, R; Mascioli, M; Floris, R; Brouqui, P

    2006-05-01

    The prevalence of antibodies to Rickettsiae and other tick-borne microrganisms in the sera of 181 forestry rangers from Friuli-Venezia-Giulia, Italy, was examined. Seven (3.9%) sera were positive for Rickettsia conorii and Rickettsia helvetica, as single or dual infections; four of these sera had been found previously to be positive for Borrelia burgdorferi. Antibodies to Coxiella burnetii were detected in five (2.8%) sera, four of which were also positive for B. burgdorferi. These findings indicate that patients in this north-eastern Italian region with fever subsequent to tick-bite should be investigated for Rickettsia and Coxiella infections.

  4. Borrelia, Rickettsia, and Ehrlichia species in bat ticks, France, 2010.

    Science.gov (United States)

    Socolovschi, Cristina; Kernif, Tahar; Raoult, Didier; Parola, Philippe

    2012-12-01

    Argas vespertilionis, an argasid tick associated with bats and bat habitats in Europe, Africa, and Asia has been reported to bite humans; however, studies investigating the presence of vector-borne pathogens in these ticks are lacking. Using molecular tools, we tested 5 A. vespertilionis ticks collected in 2010 from the floor of a bat-infested attic in southwestern France that had been converted into bedrooms. Rickettsia sp. AvBat, a new genotype of spotted fever group rickettsiae, was detected and cultivated from 3 of the 5 ticks. A new species of the Ehrlichia canis group, Ehrlichia sp. AvBat, was also detected in 3 ticks. Four ticks were infected with Borrelia sp. CPB1, a relapsing fever agent of the Borrelia group that caused fatal borreliosis in a bat in the United Kingdom. Further studies are needed to characterize these new agents and determine if the A. vespertilionis tick is a vector and/or reservoir of these agents.

  5. INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp.) FROM YUCATAN, MEXICO.

    Science.gov (United States)

    Peniche-Lara, Gaspar; Ruiz-Piña, Hugo A; Reyes-Novelo, Enrique; Dzul-Rosado, Karla; Zavala-Castro, Jorge

    2016-01-01

    Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis) and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis) by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltA and 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1%) from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

  6. Detection of Rickettsia bellii and Rickettsia amblyommii in Amblyomma longirostre (Acari: Ixodidae) from Bahia state, Northeast Brazil.

    Science.gov (United States)

    McIntosh, Douglas; Bezerra, Rodrigo Alves; Luz, Hermes Ribeiro; Faccini, João Luiz Horacio; Gaiotto, Fernanda Amato; Giné, Gastón Andrés Fernandez; Albuquerque, George Rego

    2015-01-01

    Studies investigating rickettsial infections in ticks parasitizing wild animals in the Northeast region of Brazil have been confined to the detection of Rickettsia amblyommii in immature stages of Amblyomma longirostre collected from birds in the state of Bahia, and in immatures and females of Amblyomma auricularium collected from the striped hog-nosed skunk (Conepatus semistriatus) and armadillos (Euphractus sexcinctus) in the state of Pernambuco. The current study extends the distribution of R. amblyommii (strain Aranha), which was detected in A. longirostre collected from the thin-spined porcupine Chaetomys subspinosus and the hairy dwarf porcupine Coendou insidiosus. In addition, we report the first detection of Rickettsia bellii in adults of A. longirostre collected from C. insidiosus in the state of Bahia.

  7. Detection of Rickettsia bellii and Rickettsia amblyommii in Amblyomma longirostre (Acari: Ixodidae from Bahia state, Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Douglas McIntosh

    2015-09-01

    Full Text Available Studies investigating rickettsial infections in ticks parasitizing wild animals in the Northeast region of Brazil have been confined to the detection of Rickettsia amblyommii in immature stages of Amblyomma longirostre collected from birds in the state of Bahia, and in immatures and females of Amblyomma auriculariumcollected from the striped hog-nosed skunk (Conepatus semistriatus and armadillos (Euphractus sexcinctus in the state of Pernambuco. The current study extends the distribution of R. amblyommii (strain Aranha, which was detected in A. longirostre collected from the thin-spined porcupine Chaetomys subspinosus and the hairy dwarf porcupine Coendou insidiosus. In addition, we report the first detection of Rickettsia bellii in adults of A. longirostre collected from C. insidiosus in the state of Bahia.

  8. Serological and molecular evidence for spotted fever group Rickettsia and Borrelia burgdorferi sensu lato co-infections in The Netherlands

    NARCIS (Netherlands)

    Koetsveld, Joris; Tijsse-Klasen, Ellen; Herremans, Tineke; Hovius, Joppe W. R.; Sprong, Hein

    2016-01-01

    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

  9. Spotted fever group rickettsiae detected in immature stages of ticks parasitizing on Iberian endemic lizard Lacerta schreiberi Bedriaga, 1878

    Czech Academy of Sciences Publication Activity Database

    Kubelová, M.; Papoušek, I.; Bělohlávek, T.; Goüy de Bellocq, Joëlle; Baird, Stuart J. E.; Široký, P.

    2015-01-01

    Roč. 6, č. 6 (2015), s. 711-714 ISSN 1877-959X Institutional support: RVO:68081766 Keywords : Spotted fever group rickettsiae * Rickettsia monacensis * Rickettsia helvetica * Ixodes ricinus * Lacerta schreiberi Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.690, year: 2015

  10. Bartonella quintana and Typhus Group Rickettsiae Exposure among Homeless Persons, Bogotá, Colombia.

    Science.gov (United States)

    Faccini-Martínez, Álvaro A; Márquez, Andrea C; Bravo-Estupiñan, Diana M; Calixto, Omar-Javier; López-Castillo, Christian A; Botero-García, Carlos A; Hidalgo, Marylin; Cuervo, Claudia

    2017-11-01

    In 2015, we investigated Bartonella quintana and typhus group rickettsiae in body lice from homeless persons in Bogotá, Colombia. We found B. quintana-infected body lice and seroprevalence of this microorganism in 19% of homeless persons and typhus group rickettsiae in 56%. Public health professionals should start preemptive measures and active vector control.

  11. Genome Sequence of Rickettsia hoogstraalii, a Geographically Widely Distributed Tick-Associated Bacterium.

    Science.gov (United States)

    Sentausa, Erwin; El Karkouri, Khalid; Nguyen, Thi-Tien; Caputo, Aurélia; Raoult, Didier; Fournier, Pierre-Edouard

    2014-11-06

    Rickettsia hoogstraalii is a tick-associated member of the spotted fever group rickettsiae that is geographically widely distributed. We report here the draft genome of R. hoogstraalii strain Croatica(T) (=DSM 22243 = UTMB 00003), which was isolated from Haemaphysalis sulcata ticks collected in Croatia. Copyright © 2014 Sentausa et al.

  12. Diversity of Babesia and Rickettsia species in questing Ixodes ricinus: a longitudinal study in urban, pasture, and natural habitats.

    Science.gov (United States)

    Overzier, Evelyn; Pfister, Kurt; Thiel, Claudia; Herb, Ingrid; Mahling, Monia; Silaghi, Cornelia

    2013-08-01

    In a previous study, our group investigated the Babesia spp. prevalence in questing Ixodes ricinus ticks from nine city parks in South Germany in the years 2009 and 2010. We showed predominant prevalence of B. venatorum (in previous literature also known as Babesia sp. EU1), especially in those parks in a more natural condition and with occurrence of large wild animals, such as roe deer. To obtain longitudinal data and to broaden the knowledge about this pathogen, further investigations were carried out in 2011 and 2012 in four of those city parks. Two additional habitat types were chosen for comparison of prevalence data and species analysis focusing on occurrence of potential reservoir hosts. A total of 10,303 questing I. ricinus were collected in four city parks, a pasture, and a natural area in Bavaria, and a representative number of samples were investigated for prevalence of DNA of Babesia spp. (n=4381) and Rickettsia spp. (n=2186) by PCR. In the natural and pasture area, a significantly higher Babesia spp. prevalence compared to the urban area was detected. The natural area revealed sequences of B. microti, B. venatorum, and B. capreoli. In the pasture and urban habitat, predominantly B. venatorum was found, whereas B. capreoli was less frequent and only one B. microti-infected tick was found. All B. microti sequences were 100% identical to the zoonotic Jena/Germany strain. For Rickettsia spp., the significantly highest prevalence was also detected in the natural and pasture areas, whereas lower prevalence was found in the urban area. Sequence analysis revealed R. helvetica (98%) and R. monacensis (2%). Prevalence rates and occurrence of Babesia spp. and Rickettsia spp. differed in urban, pasture and natural sites, most likely depending on the habitat structure (natural or cultivated) and therefore on the appearance and availability of reservoir hosts like roe deer or small mammals.

  13. Urban zoonoses caused by Bartonella, Coxiella, Ehrlichia, and Rickettsia species.

    Science.gov (United States)

    Comer, J A; Paddock, C D; Childs, J E

    2001-01-01

    The last half of the 20th Century witnessed an increase in the occurrence and recognition of urban zoonoses caused by members of the genera Bartonella, Coxiella, Ehrlichia, and Rickettsia, all traditionally considered to be members of the family Rickettsiaceae. In recent years, new human pathogens (Bartonella elizabethae, Bartonella henselae, and Rickettsia felis) have been recognized in urban environments. Other newly recognized pathogens (Ehrlichia chaffeensis and Ehrlichia phagocytophila in the United States) have sylvan zoonotic cycles but are present in urban areas because their vertebrate hosts and associated ectoparasitic arthropod vectors are able to survive in cities. Still other agents, which were primarily of historical importance (Bartonella quintana) or have not traditionally been associated with urban environments (Rickettsia rickettsii), have been recognized as causes of human disease in urban areas. Some diseases that have traditionally been associated with urban environments, such as rickettsialpox (caused by Rickettsia akari) and murine typhus (caused by Rickettsia typhi), still occur in large cities at low or undetermined frequencies and often go undetected, despite the availability of effective measures to diagnose and control them. In addition, alternate transmission cycles have been discovered for Coxiella burnetii, Rickettsia prowazekii, and R. typhi that differ substantially from their established, classic cycles, indicating that the epidemiology of these agents is more complex than originally thought and may be changing. Factors leading to an increase in the incidence of illnesses caused by these bacteria in urban areas include societal changes as well as intrinsic components of the natural history of these organisms that favor their survival in cities. Transovarial and transstadial transmission of many of the agents in their arthropod hosts contributes to the highly focal nature of many of the diseases they cause by allowing the pathogens

  14. Sca1, a previously undescribed paralog from autotransporter protein-encoding genes in Rickettsia species

    Directory of Open Access Journals (Sweden)

    Raoult Didier

    2006-02-01

    Full Text Available Abstract Background Among the 17 genes encoding autotransporter proteins of the "surface cell antigen" (sca family in the currently sequenced Rickettsia genomes, ompA, sca5 (ompB and sca4 (gene D, have been extensively used for identification and phylogenetic purposes for Rickettsia species. However, none of these genes is present in all 20 currently validated Rickettsia species. Of the remaining 14 sca genes, sca1 is the only gene to be present in all nine sequenced Rickettsia genomes. To estimate whether the sca1 gene is present in all Rickettsia species and its usefulness as an identification and phylogenetic tool, we searched for sca1genes in the four published Rickettsia genomes and amplified and sequenced this gene in the remaining 16 validated Rickettsia species. Results Sca1 is the only one of the 17 rickettsial sca genes present in all 20 Rickettsia species. R. prowazekii and R. canadensis exhibit a split sca1 gene whereas the remaining species have a complete gene. Within the sca1 gene, we identified a 488-bp variable sequence fragment that can be amplified using a pair of conserved primers. Sequences of this fragment are specific for each Rickettsia species. The phylogenetic organization of Rickettsia species inferred from the comparison of sca1 sequences strengthens the classification based on the housekeeping gene gltA and is similar to those obtained from the analyses of ompA, sca5 and sca4, thus suggesting similar evolutionary constraints. We also observed that Sca1 protein sequences have evolved under a dual selection pressure: with the exception of typhus group rickettsiae, the amino-terminal part of the protein that encompasses the predicted passenger domain, has evolved under positive selection in rickettsiae. This suggests that the Sca1 protein interacts with the host. In contrast, the C-terminal portion containing the autotransporter domain has evolved under purifying selection. In addition, sca1 is transcribed in R. conorii

  15. [Lymphangitis-associated rickettsiosis caused by Rickettsia sibirica mongolitimonae].

    Science.gov (United States)

    Foissac, M; Socolovschi, C; Raoult, D

    2013-01-01

    Rickettsia sibirica mongolitimonae was first isolated 20 years ago in Asia but has now been identified on three continents. Hyalomma spp. and Rhipicephalus pusillus ticks are vectors but only a small number of cases have been reported to date, mainly on the Mediterranean coast. This bacterium induces the lymphangitis-associated rickettsiosis, a still unfamiliar rickettsiosis that is mainly characterized by fever with a rope-like lymphangitis and/or lymphadenopathy and skin eschar occurring after tick bites. These features are especially evocative if they occur in spring. Sequellae are very rare and treatment with doxycycline is recommended. Copyright © 2013. Published by Elsevier Masson SAS.

  16. Rickettsioses in Europe.

    Science.gov (United States)

    Portillo, Aránzazu; Santibáñez, Sonia; García-Álvarez, Lara; Palomar, Ana M; Oteo, José A

    2015-01-01

    Bacteria of the genera Rickettsia and Orientia (family rickettsiaceae, order rickettsiales) cause rickettsioses worldwide, and are transmitted by lice, fleas, ticks and mites. In Europe, only Rickettsia spp. cause rickettsioses. With improvement of hygiene, the risk of louse-borne rickettsiosis (epidemic typhus) is low in Europe. Nevertheless, recrudescent form of Rickettsia prowazekii infection persists. There could be an epidemic typhus outbreak if a body lice epidemic occurs under unfavorable sanitary conditions. In Europe, endemic typhus or Rickettsia typhi infection, transmitted by rats and fleas, causes febrile illness. At the beginning of this century, flea-borne spotted fever cases caused by Rickettsia felis were diagnosed. Flea-borne rickettsiosis should be suspected after flea bites if fever, with or without rash, is developed. Tick-borne rickettsioses are the main source of rickettsia infections in Europe. Apart from Rickettsia conorii, the Mediterranean Spotted Fever (MSF) agent, other Rickettsia spp. cause MSF-like: Rickettsia helvetica, Rickettsia monacensis, Rickettsia massiliae or Rickettsia aeschlimannii. In the 1990s, two 'new' rickettsioses were diagnosed: Lymphangitis Associated Rickettsiosis (LAR) caused by Rickettsia sibirica mongolitimonae, and Tick-Borne Lymphadenopathy/Dermacentor-Borne-Necrosis-Erythema-Lymphadenopathy/Scalp Eschar Neck Lymphadenopathy (TIBOLA/DEBONEL/SENLAT), caused by Rickettsia slovaca, Candidatus Rickettsia rioja and Rickettsia raoultii. Lastly, European reports about mite-borne rickettsiosis are scarce. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  17. Horizontal transmission of the insect symbiont Rickettsia is plant-mediated

    Science.gov (United States)

    Caspi-Fluger, Ayelet; Inbar, Moshe; Mozes-Daube, Netta; Katzir, Nurit; Portnoy, Vitaly; Belausov, Eduard; Hunter, Martha S.; Zchori-Fein, Einat

    2012-01-01

    Bacteria in the genus Rickettsia, best known as vertebrate pathogens vectored by blood-feeding arthropods, can also be found in phytophagous insects. The presence of closely related bacterial symbionts in evolutionarily distant arthropod hosts presupposes a means of horizontal transmission, but no mechanism for this transmission has been described. Using a combination of experiments with live insects, molecular analyses and microscopy, we found that Rickettsia were transferred from an insect host (the whitefly Bemisia tabaci) to a plant, moved inside the phloem, and could be acquired by other whiteflies. In one experiment, Rickettsia was transferred from the whitefly host to leaves of cotton, basil and black nightshade, where the bacteria were restricted to the phloem cells of the plant. In another experiment, Rickettsia-free adult whiteflies, physically segregated but sharing a cotton leaf with Rickettsia-plus individuals, acquired the Rickettsia at a high rate. Plants can serve as a reservoir for horizontal transmission of Rickettsia, a mechanism which may explain the occurrence of phylogenetically similar symbionts among unrelated phytophagous insect species. This plant-mediated transmission route may also exist in other insect–symbiont systems and, since symbionts may play a critical role in the ecology and evolution of their hosts, serve as an immediate and powerful tool for accelerated evolution. PMID:22113034

  18. Rickettsial ompB promoter regulated expression of GFPuv in transformed Rickettsia montanensis.

    Directory of Open Access Journals (Sweden)

    Gerald D Baldridge

    2010-01-01

    Full Text Available Rickettsia spp. (Rickettsiales: Rickettsiaceae are Gram-negative, obligate intracellular, alpha-proteobacteria that have historically been associated with blood-feeding arthropods. Certain species cause typhus and spotted fevers in humans, but others are of uncertain pathogenicity or may be strict arthropod endosymbionts. Genetic manipulation of rickettsiae should facilitate a better understanding of their interactions with hosts.We transformed a species never associated with human disease, Rickettsia montanensis, by electroporation with a TN5 transposon (pMOD700 containing green fluorescent protein (GFPuv and chloramphenicol acetyltransferase (CAT genes under regulation of promoters cloned from the Rickettsia rickettsii ompB gene, and isolated a Chloramphenicol-resistant GFP-fluorescent rickettsiae population (Rmontanensis700. The Rmontanensis700 rickettsiae contained a single transposon integrated near an acetyl-CoA acetyltransferase gene in the rickettsial chromosome. Northern blots showed that GFPuv and CAT mRNAs were both expressed as two transcripts of larger and smaller than predicted length. Western immunoblots showed that Rmontanensis700 and E. coli transformed with a plasmid containing the pMOD700 transposon both expressed GFPuv proteins of the predicted molecular weight.Long-standing barriers to transformation of rickettsiae have been overcome by development of transposon-based rickettsial transformation vectors. The ompB promoter may be the most problematic of the four promoters so far employed in those vectors.

  19. Establishment of a replicating plasmid in Rickettsia prowazekii.

    Directory of Open Access Journals (Sweden)

    David O Wood

    Full Text Available Rickettsia prowazekii, the causative agent of epidemic typhus, grows only within the cytosol of eukaryotic host cells. This obligate intracellular lifestyle has restricted the genetic analysis of this pathogen and critical tools, such as replicating plasmid vectors, have not been developed for this species. Although replicating plasmids have not been reported in R. prowazekii, the existence of well-characterized plasmids in several less pathogenic rickettsial species provides an opportunity to expand the genetic systems available for the study of this human pathogen. Competent R. prowazekii were transformed with pRAM18dRGA, a 10.3 kb vector derived from pRAM18 of R. amblyommii. A plasmid-containing population of R. prowazekii was obtained following growth under antibiotic selection, and the rickettsial plasmid was maintained extrachromosomally throughout multiple passages. The transformant population exhibited a generation time comparable to that of the wild type strain with a copy number of approximately 1 plasmid per rickettsia. These results demonstrate for the first time that a plasmid can be maintained in R. prowazekii, providing an important genetic tool for the study of this obligate intracellular pathogen.

  20. Sequencing and comparison of the Rickettsia genomes from the whitefly Bemisia tabaci Middle East Asia Minor I.

    Science.gov (United States)

    Zhu, Dan-Tong; Xia, Wen-Qiang; Rao, Qiong; Liu, Shu-Sheng; Ghanim, Murad; Wang, Xiao-Wei

    2016-08-01

    The whitefly, Bemisia tabaci, harbors the primary symbiont 'Candidatus Portiera aleyrodidarum' and a variety of secondary symbionts. Among these secondary symbionts, Rickettsia is the only one that can be detected both inside and outside the bacteriomes. Infection with Rickettsia has been reported to influence several aspects of the whitefly biology, such as fitness, sex ratio, virus transmission and resistance to pesticides. However, mechanisms underlying these differences remain unclear, largely due to the lack of genomic information of Rickettsia. In this study, we sequenced the genome of two Rickettsia strains isolated from the Middle East Asia Minor 1 (MEAM1) species of the B. tabaci complex in China and Israel. Both Rickettsia genomes were of high coding density and AT-rich, containing more than 1000 coding sequences, much larger than that of the coexisted primary symbiont, Portiera. Moreover, the two Rickettsia strains isolated from China and Israel shared most of the genes with 100% identity and only nine genes showed sequence differences. The phylogenetic analysis using orthologs shared in the genus, inferred the proximity of Rickettsia in MEAM1 and Rickettsia bellii. Functional analysis revealed that Rickettsia was unable to synthesize amino acids required for complementing the whitefly nutrition. Besides, a type IV secretion system and a number of virulence-related genes were detected in the Rickettsia genome. The presence of virulence-related genes might benefit the symbiotic life of the bacteria, and hint on potential effects of Rickettsia on whiteflies. The genome sequences of Rickettsia provided a basis for further understanding the function of Rickettsia in whiteflies. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  1. DNA Microarray Analysis of Human Monocytes Early Response Genes upon Infection with Rickettsia rickettsii

    National Research Council Canada - National Science Library

    Chao, Chien-Chung

    2004-01-01

    Rickettsia are arthropod-borne bacteria which have caused diseases that have had a military impact by sweeping through troops and incapacitating them, such as the so called Trench Fevers of World War I and II...

  2. Amblyomma sculptum: genetic diversity and rickettsias in the Brazilian Cerrado biome.

    Science.gov (United States)

    Bitencourth, K; Amorim, M; DE Oliveira, S V; Caetano, R L; Voloch, C M; Gazêta, G S

    2017-12-01

    Amblyomma sculptum (Ixodida: Ixodidae) Berlese, 1888 is the most important tick vector in Brazil, transmitting the bioagent of the most severe form of spotted fever (SF) in part of the Cerrado (in the states of Minas Gerais and São Paulo). In another part of the Cerrado (Central-West region of Brazil), a milder form of SF has been recorded. However, neither the rickettsia nor the vector involved have been characterized. The aim of the current study was to analyse genetic variation and the presence of rickettsia in A. sculptum in Cerrado, from silent areas and with the milder form of SF. Samples were subjected to DNA extraction, amplification and sequencing of 12S rDNA, cytochrome oxidase subunit II and D-loop mitochondrial genes (for tick population analyses), and gltA, htrA, ompA and gene D (sca4) genes for rickettsia researches. Exclusive haplotypes with low frequencies, high haplotype diversity and low nucleotide diversity, star-shaped networks and significant results in neutrality tests indicate A. sculptum population expansions in some areas. Rickettsia amblyommatis, Candidatus Rickettsia andeanae and Rickettsia felis were detected. The A. sculptum diversity is not geographically, or biome delimited, pointing to a different potential in vector capacity, possibly associated with differing tick genetic profiles. © 2017 The Royal Entomological Society.

  3. THE DISTRIBUTION OF RICKETTSIA IN THE TISSUES OF INSECTS AND ARACHNIDS.

    Science.gov (United States)

    Cowdry, E V

    1923-03-31

    In the absence of a satisfactory definition of Rickettsia the observations herein recorded were arbitrarily limited to bacterium-like organisms which are intracellular and Gram-negative. Rickettsia of this type were found in the following species: Amblyomma americana, Amblyomma hebraeum, Boophilus decoloratus, Atomus sp., Casinaria infesta, Chrysopa oculata, Ctenocephalus canis, Dermacentor variabilis, Lepisma saccharina, Lucoppia curviseta, Margaropus annulatus, Margaropus annulatus australis, Ornithodoros turicata, Pulex irritans, Rhipicephalus sanguineus, Rhipicephalus evertsi, and Salticus scenicus. Since intracellular, Gram-negative Rickettsia have been recorded in the literature as existing in Cimex lectularius, Dermacentor venustus, Melophagus ovinus, and Pediculus humanus, the occasional occurrence of such bodies must be conceded in the following groups not closely related phylogenetically: Attidae, Trombidiidae, Argasidae, lxodidae, Cinura, Acanthiidae, Pediculidae, Hippoboscidae, Chrysopidae, Pulicidae, and Ichneumonidae. The species which harbor Rickettsia differ widely in diet and habitat. One such species is insectivorous throughout life, two are insectivorous in larval stages, becoming vegetarian in the adult condition, one is chiefly vegetarian but partakes of some animal products, and two are usually entirely vegetarian; while the remainder subsist wholly upon a diet of mammalian blood. Rickettsia are associated, in only a few cases, with diseases in mammals. The evidence at hand does not lead beyond the conclusion that the Rickettsia mentioned above are true Gram-negative microorganisms, easily distinguishable from mitochondria and all other cytoplasmic and nuclear granulations, rather completely adapted to an intracellular existence, exhibiting in some cases a remarkable degree of host specificity, and often inherited through the eggs.

  4. Ticks and spotted fever group rickettsiae of southeastern Virginia.

    Science.gov (United States)

    Nadolny, Robyn M; Wright, Chelsea L; Sonenshine, Daniel E; Hynes, Wayne L; Gaff, Holly D

    2014-02-01

    The incidence of tick-borne rickettsial disease in the southeastern United States has been rising steadily through the past decade, and the range expansions of tick species and tick-borne infectious agents, new and old, has resulted in an unprecedented mix of vectors and pathogens. The results of an ongoing 4-year surveillance project describe the relative abundance of questing tick populations in southeastern Virginia. Since 2009, more than 66,000 questing ticks of 7 species have been collected from vegetation in a variety of habitats, with Amblyomma americanum constituting over 95% of ticks collected. Other species represented included Ixodes scapularis, Dermacentor variabilis, Amblyomma maculatum, Ixodes affinis, Haemaphysalis leporispalustris, and Ixodes brunneus. We found that 26.9-54.9% of A. americanum ticks tested were positive for Rickettsia amblyommii, a non-pathogenic symbiont of this tick species. We also found no evidence of R. rickettsii in D. variabilis ticks, although they did show low infection rates of R. montanensis (1.5-2.0%). Rickettsia parkeri and Candidatus R. andeanae were found in 41.8-55.7% and 0-1.5% A. maculatum ticks, respectively. The rate of R. parkeri in A. maculatum ticks is among the highest in the literature and has increased in the 2 years since R. parkeri and A. maculatum were first reported in southeastern Virginia. We conclude that tick populations in southeastern Virginia have recently undergone dramatic changes in species and abundance and that these populations support a variety of rickettsial agents with the potential for increased risk to human health. Copyright © 2013 Elsevier GmbH. All rights reserved.

  5. THE ANTIGENIC RELATIONSHIP BETWEEN BACILLUS PROTEUS X-19 AND RICKETTSIAE

    Science.gov (United States)

    Castaneda, M. Ruiz

    1935-01-01

    Two substances differing in immunological behavior as well as in certain chemical properties have been isolated from soluble extracts of B. proteus X-19. Both substances appear to be polysaccharides. The first substance is precipitated from X-19 crude extracts by a relatively low percentage of alcohol and electrolytes (from one to two and a half volumes of alcohol). When purified as far as possible, it gives a negative biuret reaction, a positive Molish and has a nitrogen content of 4 per cent. This material, which we call X factor, has the immunological properties of the common antigenic factor in Proteus X-19 and typhus Rickettsiae, described elsewhere. It has the property of precipitating with typhus serum as well as anti-Proteus serum, even after treatment with hot alkali. The second substance we call P factor, suggesting a material which is proper to Proteus X-19 and has nothing to do with the Weil-Felix reaction. It is obtained from the crude extracts of B. proteus X-19 by treating the fluids from which the X factor has been removed with an excess of alcohol (seven to ten volumes, according to electrolytes in solution). The purified material shows a nitrogen content of a little less than 1 per cent, gives a negative biuret and a positive Molish reaction. The P factor produces precipitates with anti-Proteus serum in considerable dilution, but has no effect on typhus serum. It is quickly destroyed on treating with alkali, a fact in accordance with the results already cited, which were obtained by White with whole extracts of B. proteus X-19. The duality of the X-19 extracts seems to be explained by the isolation of two immunologically different factors; one which is alkali-labile and which is proper to B. proteus X-19; and the other which is alkali-stable and is the common antigenic factor in Proteus X-19 and typhus Rickettsiae. PMID:19870415

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

    Science.gov (United States)

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

    2015-01-01

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

  7. INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp. FROM YUCATAN, MEXICO

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    Gaspar PENICHE-LARA

    2016-01-01

    Full Text Available Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltAand 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1% from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

  8. Development of three quantitative real-time PCR assays for the detection of Rickettsia raoultii, Rickettsia slovaca, and Rickettsia aeschlimannii and their validation with ticks from the country of Georgia and the Republic of Azerbaijan.

    Science.gov (United States)

    Jiang, Ju; You, Brian J; Liu, Evan; Apte, Anisha; Yarina, Tamasin R; Myers, Todd E; Lee, John S; Francesconi, Stephen C; O'Guinn, Monica L; Tsertsvadze, Nikoloz; Vephkhvadze, Nino; Babuadze, Giorgi; Sidamonidze, Ketevan; Kokhreidze, Maka; Donduashvili, Marina; Onashvili, Tinatin; Ismayilov, Afrail; Agayev, Nigar; Aliyev, Mubariz; Muttalibov, Nizam; Richards, Allen L

    2012-12-01

    A previous surveillance study of human pathogens within ticks collected in the country of Georgia showed a relatively high infection rate for Rickettsia raoultii, R. slovaca, and R. aeschlimannii. These 3 spotted fever group rickettsiae are human pathogens: R. raoultii and R. slovaca cause tick-borne lymphadenopathy (TIBOLA), and R. aeschlimannii causes an infection characterized by fever and maculopapular rash. Three quantitative real-time polymerase chain reaction (qPCR) assays, Rraoul, Rslov, and Raesch were developed and optimized to detect R. raoultii, R. slovaca, and R. aeschlimannii, respectively, by targeting fragments of the outer membrane protein B gene (ompB) using species-specific molecular beacon or TaqMan probes. The 3 qPCR assays showed 100% specificity when tested against a rickettsiae DNA panel (n=20) and a bacteria DNA panel (n=12). The limit of detection was found to be at least 3 copies per reaction for all assays. Validation of the assays using previously investigated tick nucleic acid preparations, which included Rickettsia-free tick samples, tick samples that contain R. raoultii, R. slovaca, R. aeschlimannii, and other Rickettsia spp., gave 100% sensitivity for all 3 qPCR assays. In addition, a total of 65 tick nucleic acid preparations (representing 259 individual ticks) collected from the country of Georgia and the Republic of Azerbaijan in 2009 was tested using the 3 qPCR assays. R. raoultii, R. slovaca, and R. aeschlimannii were not detected in any ticks (n=31) from the Republic of Azerbaijan, but in the ticks from the country of Georgia (n=228) the minimal infection rate for R. raoultii and R. slovaca in Dermacentor marginatus was 10% and 4%, respectively, and for R. aeschlimannii in Haemaphysalis sulcata and Hyalomma spp. it was 1.9% and 20%, respectively. Published by Elsevier GmbH.

  9. Rickettsia spp. among wild mammals and their respective ectoparasites in Pantanal wetland, Brazil.

    Science.gov (United States)

    de Sousa, Keyla Carstens Marques; Herrera, Heitor Miraglia; Rocha, Fabiana Lopes; Costa, Francisco Borges; Martins, Thiago Fernandes; Labruna, Marcelo Bahia; Machado, Rosangela Zacarias; André, Marcos Rogério

    2018-01-01

    The genus Rickettsia comprises obligatory intracellular bacteria, well known to cause zoonotic diseases around the world. The present work aimed to investigate the occurrence of Rickettsia spp. in wild animals, domestic dogs and their respective ectoparasites in southern Pantanal region, central-western Brazil, by molecular and serological techniques. Between August 2013 and March 2015, serum, whole blood and/or spleen samples were collected from 31 coatis, 78 crab-eating foxes, seven ocelots, 42 dogs, 110 wild rodents, and 30 marsupials. Serum samples from canids, felids, rodents and marsupials were individually tested by indirect fluorescent antibody test (IFAT) in order to detect IgG antibodies to Rickettsia rickettsii, Rickettsia parkeri and Rickettsia amblyommatis. DNA samples from mammals and ectoparasites were submitted to a multiplex qPCR assay in order to detect and quantify spotted fever group (SFG) and typhus group (TG) rickettsiae and Orientia tsutsugamushi. Positive samples in qPCR assays were submitted to conventional PCR assays targeting gltA, ompA, ompB and htrA genes, followed by sequencing and phylogenetic analyses. The ticks collected (1582) from animals belonged to the species Amblyomma sculptum, Amblyomma parvum, Amblyomma ovale, Amblyomma tigrinum, Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus sensu lato and Amblyomma auricularium. Overall, 27 (64.2%) dogs, 59 (75.6%) crab-eating foxes and six (85.7%) ocelots were seroreactive (titer≥64) to at least one Rickettsia species. For 17 (40.4%) dogs, 33 (42.3%) crab-eating foxes, and two (33.3%) ocelots, homologous reactions to R. amblyommatis or a closely related organism were suggested. One hundred and sixteen (23.5%) tick samples and one (1.2%) crab-eating fox blood sample showed positivity in qPCR assays for SFG Rickettsia spp. Among SFG Rickettsia-positive ticks samples, 93 (80.2%) belonged to A. parvum, 14 (12%) belonged to A. sculptum species, three (2.5%) belonged to A

  10. Wholly Rickettsia! Reconstructed Metabolic Profile of the Quintessential Bacterial Parasite of Eukaryotic Cells

    Directory of Open Access Journals (Sweden)

    Timothy P. Driscoll

    2017-09-01

    Full Text Available Reductive genome evolution has purged many metabolic pathways from obligate intracellular Rickettsia (Alphaproteobacteria; Rickettsiaceae. While some aspects of host-dependent rickettsial metabolism have been characterized, the array of host-acquired metabolites and their cognate transporters remains unknown. This dearth of information has thwarted efforts to obtain an axenic Rickettsia culture, a major impediment to conventional genetic approaches. Using phylogenomics and computational pathway analysis, we reconstructed the Rickettsia metabolic and transport network, identifying 51 host-acquired metabolites (only 21 previously characterized needed to compensate for degraded biosynthesis pathways. In the absence of glycolysis and the pentose phosphate pathway, cell envelope glycoconjugates are synthesized from three imported host sugars, with a range of additional host-acquired metabolites fueling the tricarboxylic acid cycle. Fatty acid and glycerophospholipid pathways also initiate from host precursors, and import of both isoprenes and terpenoids is required for the synthesis of ubiquinone and the lipid carrier of lipid I and O-antigen. Unlike metabolite-provisioning bacterial symbionts of arthropods, rickettsiae cannot synthesize B vitamins or most other cofactors, accentuating their parasitic nature. Six biosynthesis pathways contain holes (missing enzymes; similar patterns in taxonomically diverse bacteria suggest alternative enzymes that await discovery. A paucity of characterized and predicted transporters emphasizes the knowledge gap concerning how rickettsiae import host metabolites, some of which are large and not known to be transported by bacteria. Collectively, our reconstructed metabolic network offers clues to how rickettsiae hijack host metabolic pathways. This blueprint for growth determinants is an important step toward the design of axenic media to rescue rickettsiae from the eukaryotic cell.

  11. Multispacer typing of Rickettsia isolates from humans and ticks in Tunisia revealing new genotypes.

    Science.gov (United States)

    Znazen, Abir; Khrouf, Fatma; Elleuch, Nihel; Lahiani, Dorra; Marrekchi, Chakib; M'Ghirbi, Youmna; Ben Jemaa, Mounir; Bouattour, Ali; Hammami, Adnene

    2013-12-31

    Rickettsioses are important remerging vector born infections. In Tunisia, many species have been described in humans and vectors. Genotyping is important for tracking pathogen movement between hosts and vectors. In this study, we characterized Rickettsia species detected in patients and vectors using multispacer typing (MST), proposed by Founier et al. and based on three intergenic spacers (dksA-xerC, rmpE- tRNA(fMet), mppA-pruC) sequencing. Our study included 25 patients hospitalized during 2009. Ticks and fleas were collected in the vicinity of confirmed cases. Serology was performed on serum samples by microimmunofluorescence using Rickettsia conorii and Rickettsia typhi antigens. To detect and identify Rickettsia species, PCR targeting ompA, ompB and gltA genes followed by sequencing was performed on 18 obtained skin biopsies and on all collected vectors. Rickettsia positive samples were further characterized using primers targeting three intergenic spacers (dksA-xerC, rmpE- tRNA(fMet) and mppA-purC). A rickettsial infection was confirmed in 15 cases (60%). Serology was positive in 13 cases (52%). PCR detected Rickettsia DNA in four biopsies (16%) allowing the identification of R. conorii subsp israelensis in three cases and R. conorii subsp conorii in one case. Among 380 collected ticks, nine presented positive PCR (2.4%) allowing the identification of six R. conorii subsp israelensis, two R. massiliae and one R. conorii subsp conorii. Among 322 collected fleas, only one was positive for R. felis. R. conorii subsp israelensis strains detected in humans and vectors clustered together and showed a new MST genotype. Similarly, R. conorii subsp conorii strains detected in a skin biopsy and a tick were genetically related and presented a new MST genotype. New Rickettsia spotted fever strain genotypes were found in Tunisia. Isolates detected in humans and vectors were genetically homogenous despite location differences in their original isolation suggesting

  12. Mapping of Monoclonal Antibody Binding Sites on CNBr Fragments of the S- Layer Protein Antigens of Rickettsia Typhi and Rickettsia Prowazekii

    Science.gov (United States)

    1992-01-01

    Security Clasification ) Mapping of monoclonal antibody binding sites on CNBr fragments o; the S-layer protein antigens of Rickettsia Typhi and...homology was found in all the viral polypeptides have long fatty acids attached to fragments which react with type I antibody (Fig. 4). A their N-termini

  13. Proposal to create subspecies of Rickettsia conorii based on multi-locus sequence typing and an emended description of Rickettsia conorii

    Directory of Open Access Journals (Sweden)

    Raoult Didier

    2005-03-01

    Full Text Available Abstract Background Rickettsiae closely related to the Malish strain, the reference Rickettsia conorii strain, include Indian tick typhus rickettsia (ITTR, Israeli spotted fever rickettsia (ISFR, and Astrakhan fever rickettsia (AFR. Although closely related genotypically, they are distinct serotypically. Using multilocus sequence typing (MLST, we have recently found that distinct serotypes may not always represent distinct species within the Rickettsia genus. We investigated the possibility of classifying rickettsiae closely related to R. conorii as R. conorii subspecies as proposed by the ad hoc committee on reconciliation of approaches to bacterial systematics. For this, we first estimated their genotypic variability by using MLST including the sequencing of 5 genes, of 31 rickettsial isolates closely related to R. conorii strain Malish, 1 ITTR isolate, 2 isolates and 3 tick amplicons of AFR, and 2 ISFR isolates. Then, we selected a representative of each MLST genotype and used multi-spacer typing (MST and mouse serotyping to estimate their degree of taxonomic relatedness. Results Among the 39 isolates or tick amplicons studied, four MLST genotypes were identified: i the Malish type; ii the ITTR type; iii the AFR type; and iv the ISFR type. Among these four MLST genotypes, the pairwise similarity in nucleotide sequence varied from 99.8 to 100%, 99.4 to 100%, 98.2 to 99.8%, 98.4 to 99.8%, and 99.2 to 99.9% for 16S rDNA, gltA, ompA, ompB, and sca4 genes, respectively. Representatives of the 4 MLST types were also classified within four types using MST genotyping as well as mouse serotyping. Conclusion Although homogeneous genotypically, strains within the R. conorii species show MST genotypic, serotypic, and epidemio-clinical dissimilarities. We, therefore, propose to modify the nomenclature of the R. conorii species through the creation of subspecies. We propose the names R. conorii subsp. conorii subsp. nov. (type strain = Malish, ATCC VR-613

  14. Vector competence of Amblyomma americanum (Acari: Ixodidae) for Rickettsia rickettsii.

    Science.gov (United States)

    Levin, Michael L; Zemtsova, Galina E; Killmaster, Lindsay F; Snellgrove, Alyssa; Schumacher, Lauren B M

    2017-06-01

    Rickettsia rickettsii - the etiologic agent of Rocky Mountain spotted fever (RMSF) - is widely spread across the Americas. In the US, Dermacentor spp. ticks are identified as primary vectors of R. rickettsii and Rhipicephalus sanguineus s.l. has been implicated in transmission of this pathogen in several locations in the Southwest. Conversely, ticks of the genus Amblyomma are recognized vectors of RMSF in Central and South America, but not in the US. A. americanum is one of the most aggressive human-biting ticks in the US, whose geographical range overlaps with that of reported RMSF cases. Despite sporadic findings of R. rickettsii DNA in field-collected A. americanum and circumstantial association of this species with human RMSF cases, its vector competence for R. rickettsii has not been appropriately studied. Therefore, we assessed the ability of A. americanum to acquire and transmit two geographically distant isolates of R. rickettsii. The Di-6 isolate of R. rickettsii used in this study originated in Virginia and the AZ-3 isolate originated in Arizona. Under laboratory conditions, A. americanum demonstrated vector competence for both isolates, although the efficiency of acquisition and transovarial transmission was higher for Di-6 than for AZ-3 isolate. Uninfected larvae acquired the pathogen from systemically infected guinea pigs, as well as while feeding side by side with Rickettsia-infected ticks on non-rickettsiemic hosts. Once acquired, R. rickettsii was successfully maintained through the tick molting process and transmitted to susceptible animals during subsequent feedings. Guinea pigs and dogs infested with infected A. americanum developed fever, scrotal edema and dermatitis or macular rash. R. rickettsii DNA was identified in animal blood, skin, and internal organs. The prevalence of infection within tick cohorts gradually increased due to side-by-side feeding of infected and uninfected individuals from 33 to 49% in freshly molted nymphs to 71-98% in

  15. Presence of Pathogenic Rickettsiae and Protozoan in Samples of Raw Milk from Cows, Goats, and Sheep.

    Science.gov (United States)

    Cisak, Ewa; Zając, Violetta; Sroka, Jacek; Sawczyn, Anna; Kloc, Anna; Dutkiewicz, Jacek; Wójcik-Fatla, Angelina

    2017-04-01

    The aim of the present work was to determine the presence of various rickettsiae and protozoan in raw milk and the assessment the potential, milk-borne route in the spread of selected zoonotic pathogens. A total of 119 raw milk samples collected randomly from 63 cows, 29 goats, and 27 sheep bred on 34 farms situated on eight communities in eastern Poland were examined by polymerase chain reaction (PCR) method for the presence of pathogenic rickettsiae (Coxiella burnetii, Anaplasma phagocytophilum, and Rickettsia spp.) and protozoan (Toxoplasma gondii). The only prevalent pathogen was T. gondii, which was found in 10 samples of cow milk (15.9%), in one sample of goat milk (3.4%), and in one sample of sheep milk (3.7%). One sample of cow milk was positive for C. burnetii; however, the sequence analysis did not confirm any species of Coxiella or Coxiella-like organisms, but showed 100% homology to Psychrobacter alimentarius. None of the examined samples showed the presence of A. phagocytophilum or Rickettsia spp. The results of this study suggest a potential hazard of milk-borne Toxoplasma infection, mostly by consumption of raw cow milk. The milk-borne spread seems to be limited or nonsignificant in the case of C. burnetii, A. phagocytophilum, and Rickettsia spp. The false-positive sample for Coxiella spp. suggests that some care should be taken in the interpretation of the results obtained by using the PCR method.

  16. Rickettsia lusitaniae associated with Ornithodoros yumatensis (Acari: Argasidae) from two caves in Yucatan, Mexico.

    Science.gov (United States)

    Sánchez-Montes, Sokani; Guzmán-Cornejo, Carmen; Martínez-Nájera, Yecenia; Becker, Ingeborg; Venzal, José M; Labruna, Marcelo B

    2016-10-01

    The genus Rickettsia includes obligate intracellular bacteria transmitted by several hematophagous arthropods such as ticks, fleas and sucking lice. In particular hard ticks (Ixodidae) have been cited as the main vectors of pathogenic rickettsiae in Mexico. However, there have been only two records of a single Rickettsia species associated with Mexican soft ticks (Argasidae). In this study, we searched for rickettsial DNA in argasid ticks (13 adults and eight nymphs of Ornithodoros yumatensis) from two bat caves in the state of Yucatan, Mexico. Additionally one larva collected in a cave from Chiapas, Mexico, and associated with Desmodus rotundus was used to corroborate the tick taxonomic determination. Of these, nine ticks (43%) yielded expected PCR products for the rickettsial gltA gene. These PCR-positive ticks were tested with additional PCR protocols targeting the rickettsial genes gltA, ompA and ompB. DNA partial sequences from these genes showed 99-100% identities with Rickettsia lusitaniae, an agent isolated from O. erraticus in Portugal, and closely related to R. felis and R. hoogstraalii. Based on the results from this study, the inventory of rickettsiae distributed in Mexico increases from six to seven species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. The Facultative Symbiont Rickettsia Protects an Invasive Whitefly against Entomopathogenic Pseudomonas syringae Strains

    Science.gov (United States)

    Hunter, Martha S.; Baltrus, David A.

    2014-01-01

    Facultative endosymbionts can benefit insect hosts in a variety of ways, including context-dependent roles, such as providing defense against pathogens. The role of some symbionts in defense may be overlooked, however, when pathogen infection is transient, sporadic, or asymptomatic. The facultative endosymbiont Rickettsia increases the fitness of the sweet potato whitefly (Bemisia tabaci) in some populations through mechanisms that are not yet understood. In this study, we investigated the role of Rickettsia in mediating the interaction between the sweet potato whitefly and Pseudomonas syringae, a common environmental bacterium, some strains of which are pathogenic to aphids. Our results show that P. syringae multiplies within whiteflies, leading to host death, and that whiteflies infected with Rickettsia show a decreased rate of death due to P. syringae. Experiments using plants coated with P. syringae confirmed that whiteflies can acquire the bacteria at a low rate while feeding, leading to increased mortality, particularly when the whiteflies are not infected with Rickettsia. These results suggest that P. syringae may affect whitefly populations in nature and that Rickettsia can ameliorate this effect. This study highlights the possible importance of interactions among opportunistic environmental pathogens and endosymbionts of insects. PMID:25217020

  18. Evidence of Extensive Homologous Recombination in the Core Genome of Rickettsia

    Directory of Open Access Journals (Sweden)

    Jinyu Wu

    2009-01-01

    Full Text Available The important role of homologous recombination has been extensively demonstrated to be fundamental for genetic variation in bacterial genomes. In contrast to extracellular or facultative intracellular bacteria, obligate intracellular bacteria are considered to be less prone to recombination, especially for their core genomes. In Rickettsia, only antigen-related genes were identified to have experienced homologous recombination. In this study, we employed evolutionary genomic approaches to investigate the impact of recombination on the core genome of Rickettsia. Phylogenetic network and phylogenetic compatibility matrix analyses are clearly consistent with the hypothesis that recombination has occurred frequently during Rickettsia evolution. 28% of Rickettsia core genes (194 out of 690 are found to present the evidence of recombination under four independent statistical methods. Further functional classification shows that these recombination events occur across all functional categories, with a significant overrepresentation in the cell wall/membrane/envelope biogenesis, which may provide a molecular basis for the parasite adaptation to host immunity. This evolutionary genomic analysis provides insight into the substantial role of recombination in the evolution of the intracellular pathogenic bacteria Rickettsia.

  19. Rickettsia parkeri infecting free-living Amblyomma triste ticks in the Brazilian Pantanal.

    Science.gov (United States)

    Melo, Andréia L T; Alves, Alvair S; Nieri-Bastos, Fernanda A; Martins, Thiago F; Witter, Rute; Pacheco, Thábata A; Soares, Herbert S; Marcili, Arlei; Chitarra, Cristiane S; Dutra, Valéria; Nakazato, Luciano; Pacheco, Richard C; Labruna, Marcelo B; Aguiar, Daniel M

    2015-04-01

    The present study evaluated the infection of rickettsiae in 151 Rhipicephalus sanguineus, 59 Amblyomma ovale, 166 Amblyomma triste, one Amblyomma dissimile and four Amblyomma dubitatum ticks collected in the municipality of Poconé, State of Mato Grosso, within the Pantanal biome of Brazil. Ticks were individually processed by the hemolymph test with Gimenez staining, isolation of rickettsia in Vero cell culture by the shell vial technique, and polymerase chain reaction (PCR) targeting the citrate synthase rickettsial gene. Through the shell vial technique, rickettsiae were successfully isolated and established in Vero cell culture from one free-living A. triste female tick, which previously showed to contain Rickettsia-like organisms by the hemolymph test. Molecular characterization of the rickettsial isolate was achieved through DNA partial sequences of three rickettsial genes (gltA, ompA, ompB), which showed to be all 100% identical to Rickettsia parkeri. After testing all ticks by PCR, the frequency of R. parkeri infection was 7.23% (12/166) in A. triste adult ticks. The remaining ticks were negative by PCR. This is the first report of in vitro isolation of R. parkeri in the Pantanal biome, confirming the occurrence of this emerging rickettsial pathogen in this natural area of South America. Copyright © 2015 Elsevier GmbH. All rights reserved.

  20. High prevalence of Rickettsia typhi and Bartonella species in rats and fleas, Kisangani, Democratic Republic of the Congo

    NARCIS (Netherlands)

    Laudisoit, A.; Falay, D.; Amundala, N.; de Bellock, J.G.; van Houtte, N.; Breno, M.; Verheven, E.; Wilschut, Liesbeth; Parola, P.; Raoult, D.; C., Socolovschi

    2014-01-01

    The prevalence and identity of Rickettsia and Bartonella in urban rat and flea populations were evaluated in Kisangani, Democratic Republic of the Congo (DRC) by molecular tools. An overall prevalence of 17% Bartonella species and 13% Rickettsia typhi, the agent of murine typhus, was found in the

  1. Molecular detection of Rickettsia amblyommii in Amblyomma americanum parasitizing humans.

    Science.gov (United States)

    Jiang, Ju; Yarina, Tamasin; Miller, Melissa K; Stromdahl, Ellen Y; Richards, Allen L

    2010-05-01

    A quantitative real-time polymerase chain reaction assay to detect and quantify a portion of the outer membrane protein B gene (ompB) of Rickettsia amblyommii was employed to assess the threat of R. amblyommii exposure to humans parasitized by Amblyomma americanum (the lone star tick). A total of 72 pools of lone star ticks removed from humans were acquired from two collections and used in this study: 44 pools of A. americanum submitted to the Department of Defense Human Tick Test Kit Program in 2003 collected from 220 individuals from 14 states, and 28 pools of A. americanum representing 120 ticks obtained from boy scouts and adult leaders at the Boy Scouts of America National Jamboree held at Fort A.P. Hill, Virginia, in 2005. Of the 72 lone star tick pools representing 340 lone star ticks, 58 pools (80.5%) were positive for R. amblyommii. In addition, individual A. americanum ticks parasitizing humans collected as part of the Department of Defense Human Tick Test Kit Program in 2002 and 2003 from 17 states were evaluated. It was found that 244 of 367 (66.5%) individual A. americanum ticks tested positive for the presence of R. amblyommii DNA. These results clearly show that lone star ticks parasitizing humans are highly infected with R. amblyommii, which may potentiate rickettsial infection of and possibly disease in humans.

  2. Molecular Detection and Identification of Spotted Fever Group Rickettsiae in Ticks Collected from the West Bank, Palestinian Territories.

    Directory of Open Access Journals (Sweden)

    Suheir Ereqat

    2016-01-01

    Full Text Available Tick-borne rickettsioses are caused by obligate intracellular bacteria belonging to the spotted fever group (SFG rickettsiae. Although Spotted Fever is prevalent in the Middle East, no reports for the presence of tick-borne pathogens are available or any studies on the epidemiology of this disease in the West Bank. We aimed to identify the circulating hard tick vectors and genetically characterize SFG Rickettsia species in ixodid ticks from the West Bank-Palestinian territories.A total of 1,123 ixodid ticks belonging to eight species (Haemaphysalis parva, Haemaphysalis adleri, Rhipicephalus turanicus, Rhipicephalus sanguineus, Rhipicephalus bursa, Hyalomma dromedarii, Hyalomma aegyptium and Hyalomma impeltatum were collected from goats, sheep, camels, dogs, a wolf, a horse and a tortoise in different localities throughout the West Bank during the period of January-April, 2014. A total of 867 ticks were screened for the presence of rickettsiae by PCR targeting a partial sequence of the ompA gene followed by sequence analysis. Two additional genes, 17 kDa and 16SrRNA were also targeted for further characterization of the detected Rickettsia species. Rickettsial DNA was detected in 148 out of the 867 (17% tested ticks. The infection rates in Rh. turanicus, Rh. sanguineus, H. adleri, H. parva, H. dromedarii, and H. impeltatum ticks were 41.7, 11.6, 16.7, 16.2, 11.8 and 20%, respectively. None of the ticks, belonging to the species Rh. bursa and H. aegyptium, were infected. Four SFG rickettsiae were identified: Rickettsia massiliae, Rickettsia africae, Candidatus Rickettsia barbariae and Candidatus Rickettsia goldwasserii.The results of this study demonstrate the geographic distribution of SFG rickettsiae and clearly indicate the presence of at least four of them in collected ticks. Palestinian clinicians should be aware of emerging tick-borne diseases in the West Bank, particularly infections due to R. massiliae and R. africae.

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

    Science.gov (United States)

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

    2015-11-01

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

  4. Orientia, rickettsia, and leptospira pathogens as causes of CNS infections in Laos

    DEFF Research Database (Denmark)

    Dittrich, Sabine; Rattanavong, Sayaphet; Lee, Sue J

    2015-01-01

    , Neisseria meningitidis, Haemophilus influenzae, S suis) and O tsutsugamushi, Rickettsia typhi/Rickettsia spp, and Leptospira spp infections in blood or cerebrospinal fluid (CSF). We analysed and compared causes and clinical and CSF characteristics between patient groups. FINDINGS: 1051 (95%) of 1112...... patients who presented had CSF available for analysis, of whom 254 (24%) had a CNS infection attributable to a bacterial or fungal pathogen. 90 (35%) of these 254 infections were caused by O tsutsugamushi, R typhi/Rickettsia spp, or Leptospira spp. These pathogens were significantly more frequent than...... conventional bacterial infections (90/1051 [9%] vs 42/1051 [4%]; pLeptospira spp combined, and 33% (13/39) for conventional bacterial...

  5. RickA expression is not sufficient to promote actin-based motility of Rickettsia raoultii.

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    Premanand Balraj

    Full Text Available BACKGROUND: Rickettsia raoultii is a novel Rickettsia species recently isolated from Dermacentor ticks and classified within the spotted fever group (SFG. The inability of R. raoultii to spread within L929 cells suggests that this bacterium is unable to polymerize host cell actin, a property exhibited by all SFG rickettsiae except R. peacocki. This result led us to investigate if RickA, the protein thought to generate actin nucleation, was expressed within this rickettsia species. METHODOLOGY/PRINCIPAL FINDINGS: Amplification and sequencing of R. raoultii rickA showed that this gene encoded a putative 565 amino acid protein highly homologous to those found in other rickettsiae. Using immunofluorescence assays, we determined that the motility pattern (i.e. microcolonies or cell-to-cell spreading of R. raoultii was different depending on the host cell line in which the bacteria replicated. In contrast, under the same experimental conditions, R. conorii shares the same phenotype both in L929 and in Vero cells. Transmission electron microscopy analysis of infected cells showed that non-motile bacteria were free in the cytosol instead of enclosed in a vacuole. Moreover, western-blot analysis demonstrated that the defect of R. raoultii actin-based motility within L929 cells was not related to lower expression of RickA. CONCLUSION/SIGNIFICANCE: These results, together with previously published data about R. typhi, strongly suggest that another factor, apart from RickA, may be involved with be responsible for actin-based motility in bacteria from the Rickettsia genus.

  6. Molecular evidence of Rickettsia felis infection in dogs from northern territory, Australia

    Directory of Open Access Journals (Sweden)

    Rees Robert L

    2011-10-01

    Full Text Available Abstract The prevalence of spotted fever group rickettsial infection in dogs from a remote indigenous community in the Northern Territory (NT was determined using molecular tools. Blood samples collected from 130 dogs in the community of Maningrida were subjected to a spotted fever group (SFG-specific PCR targeting the ompB gene followed by a Rickettsia felis-specific PCR targeting the gltA gene of R. felis. Rickettsia felis ompB and gltA genes were amplified from the blood of 3 dogs. This study is the first report of R. felis infection in indigenous community dogs in NT.

  7. Rickettsia hoogstraalii sp. nov., isolated from hard- and soft-bodied ticks.

    Science.gov (United States)

    Duh, Darja; Punda-Polic, Volga; Avsic-Zupanc, Tatjana; Bouyer, Donald; Walker, David H; Popov, Vsevolod L; Jelovsek, Mateja; Gracner, Maja; Trilar, Tomi; Bradaric, Nikola; Kurtti, Timothy J; Strus, Jasna

    2010-04-01

    A novel spotted fever group Rickettsia was found in Haemaphysalis sulcata ticks collected from sheep and goats in Croatia in 2006. At the same time, a genetically identical organism was co-isolated with the embryonic cell line CCE3 obtained from the soft tick Carios capensis in Georgia, USA. In this study, further phenotypic and genotypic characteristics of the novel rickettsial strain present in H. sulcata ticks were investigated. Based on the cultivation of bacteria in mosquito and Vero cell cultures, the presence of rickettsiae in tick tissues and cell cultures [confirmed by transmission electron microscopy (TEM)] and the amplification and sequencing of five rickettsial genes, it was demonstrated that the novel Rickettsia strain fulfils the criteria to be classified as a novel species. The name Rickettsia hoogstraalii sp. nov. is proposed for the new strain. Rickettsia hoogstraalii sp. nov., an obligately intracellular bacterium, was grown in Vero cells and arthropod CCE3, ISE6 and C6/36 cell lines. The morphology of the cells of the novel species was typical of SFG rickettsiae. The small coccobacillary appearance of the bacteria was apparent with light microscopy. A Gram-negative bacterial cell wall and a cytoplasmic membrane separated by a narrow periplasmic space were visible by TEM. To date, Rickettsia hoogstraalii sp. nov. has been isolated from two species of ticks, H. sulcata and C. capensis. The novel species appears to be geographically widely distributed, having been detected in Croatia, Spain and Georgia, USA. Although no information is available regarding the possible pathogenicity of the novel species for vertebrate hosts, R. hoogstraalii sp. nov. has a cytopathic effect in Vero, CCE3 and ISE6 cells. Sequence analyses of the 16S rRNA, 17 kDa, gltA, ompA and ompB genes indicated that even though R. hoogstraalii sp. nov. was closely related to Rickettsia felis, it represents a separate species within the spotted fever group. The type strain of R

  8. Rickettsia sp. strain colombianensi (Rickettsiales: Rickettsiaceae): a new proposed Rickettsia detected in Amblyomma dissimile (Acari: Ixodidae) from iguanas and free-living larvae ticks from vegetation.

    Science.gov (United States)

    Miranda, Jorge; Portillo, Aránzazu; Oteo, José A; Mattar, Salim

    2012-07-01

    From January to December 2009, 55 Amblyomma dissimile (Koch) ticks removed from iguanas in the municipality of Monteria and 3,114 ticks [458 Amblyomma sp. larvae, 2,636 Rhipicephalus microplus (Canestrini) larvae and 20 Amblyomma sp. nymphs] collected over vegetation in Los Cordobas were included in the study. The ticks were pooled into groups from which DNA was extracted. For initial screening of Rickettsia sp., each pool was analyzed by gltA real-time polymerase chain reaction (PCR). Positive pools were further studied using gltA, ompA, and ompB conventional PCR assays. Sequencing and phylogenetic analysis were also conducted. Rickettsial DNA was found in 28 pools of ticks (16 A. dissimile pools and 12 free-living larvae pools) out of 113 (24.7%) using real-time PCR. The same 28 pools were also positive using conventional PCR assays aimed to amplify gltA, ompA, and ompB. For each gene analyzed, PCR products obtained from 4/28 pools (two pools of A. dissimile, one pool of Amblyomma sp. larvae and one pool of Rh. microplus larvae) were randomly chosen and sequenced twice. Nucleotide sequences generated were identical to each other for each of the rickettsial genes gltA, ompA, and ompB, and showed 99.4, 95.6, and 96.4% identity with those of Rickettsia tamurae. They were deposited in the GenBank database under accession numbers JF905456, JF905458, and JF905457, respectively. In conclusion, we present the first molecular evidence of a novel Rickettsia (Rickettsia sp. strain Colombianensi) infecting A. dissimile ticks collected from iguanas, and also Rh. microplus and unspeciated Amblyomma larvae from vegetation in Colombia.

  9. Bacteria of the genus Rickettsia in ticks (Acari: Ixodidae) collected from birds in Costa Rica

    Czech Academy of Sciences Publication Activity Database

    Ogrzewalska, M.; Literák, I.; Čapek, Miroslav; Sychra, O.; Calderón, V. Á.; Rodríguez, B. C.; Prudencio, C.; Martins, T. F.; Labruna, M. B.

    2015-01-01

    Roč. 6, č. 4 (2015), s. 478-482 ISSN 1877-959X R&D Projects: GA AV ČR IAA601690901 Institutional support: RVO:68081766 Keywords : Rickettsia * Ticks * Birds * Ixodes * Amblyomma * Costa Rica Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.690, year: 2015

  10. Rickettsia bellii in ticks Amblyomma varium Koch, 1844, from birds in Peru

    Czech Academy of Sciences Publication Activity Database

    Ogrzewalska, M.; Literák, I.; Cárdenas-Callirgos, J. M.; Čapek, Miroslav; Labruna, M. B.

    2012-01-01

    Roč. 3, č. 4 (2012), s. 254-256 ISSN 1877-959X R&D Projects: GA AV ČR IAA601690901; GA MŠk LC06073 Institutional support: RVO:68081766 Keywords : Rickettsia bellii * ticks * Amblyomma calcaratum * birds * Peru Subject RIV: EG - Zoology Impact factor: 2.353, year: 2012

  11. First report of Rickettsia raoultii in field collected Dermacentor reticulatus ticks from Austria

    Czech Academy of Sciences Publication Activity Database

    Duscher, G. G.; Hodžić, A.; Weiler, M.; Vaux, A. G. C.; Rudolf, Ivo; Sixl, W.; Medlock, J. M.; Versteirt, V.; Hubálek, Zdeněk

    2016-01-01

    Roč. 7, č. 5 (2016), s. 720-722 ISSN 1877-959X Institutional support: RVO:68081766 Keywords : Rickettsia raoultii * Dermacentor reticulatus * TIBOLA * DEBONEL * Austria Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.230, year: 2016

  12. Rickettsia typhi and R. felis in Rat Fleas (Xenopsylla cheopis), Oahu, Hawaii

    OpenAIRE

    Eremeeva, Marina E.; Warashina, Wesley R.; Sturgeon, Michele M.; Buchholz, Arlene E.; Olmsted, Gregory K.; Park, Sarah Y.; Effler, Paul V.; Karpathy, Sandor E.

    2008-01-01

    Rickettsia typhi (prevalence 1.9%) and R. felis (prevalence 24.8%) DNA were detected in rat fleas (Xenopsylla cheopis) collected from mice on Oahu Island, Hawaii. The low prevalence of R. typhi on Oahu suggests that R. felis may be a more common cause of rickettsiosis than R. typhi in Hawaii.

  13. Rickettsia typhi and R. felis in rat fleas (Xenopsylla cheopis), Oahu, Hawaii.

    Science.gov (United States)

    Eremeeva, Marina E; Warashina, Wesley R; Sturgeon, Michele M; Buchholz, Arlene E; Olmsted, Gregory K; Park, Sarah Y; Effler, Paul V; Karpathy, Sandor E

    2008-10-01

    Rickettsia typhi (prevalence 1.9%) and R. felis (prevalence 24.8%) DNA were detected in rat fleas (Xenopsylla cheopis) collected from mice on Oahu Island, Hawaii. The low prevalence of R. typhi on Oahu suggests that R. felis may be a more common cause of rickettsiosis than R. typhi in Hawaii.

  14. Evidence of Rickettsia and Orientia Infections Among Abattoir Workers in Djibouti.

    Science.gov (United States)

    Horton, Katherine C; Jiang, Ju; Maina, Alice; Dueger, Erica; Zayed, Alia; Ahmed, Ammar Abdo; Pimentel, Guillermo; Richards, Allen L

    2016-08-03

    Of 49 workers at a Djiboutian abattoir, eight (16%, 95% confidence interval [CI]: 9-29) were seropositive against spotted fever group rickettsiae (SFGR), two (4%, 95% CI: 1-14) against typhus group rickettsiae, and three (6%, 95% CI: 2-17) against orientiae. One worker (9%, 95% CI: 2-38) seroconverted against orientiae during the study period. This is the first evidence of orientiae exposure in the Horn of Africa. SFGR were also identified by polymerase chain reaction in 32 of 189 (11%, 95% CI: 8-15) tick pools from 26 of 72 (36%) cattle. Twenty-five (8%, 95% CI: 6-12) tick pools were positive for Rickettsia africae, the causative agent of African tick-bite fever. Health-care providers in Djibouti should be aware of the possibility of rickettsiae infections among patients, although further research is needed to determine the impact of these infections in the country. © The American Society of Tropical Medicine and Hygiene.

  15. Molecular detection of Rickettsia species in Amblyomma ticks collected from snakes in Thailand

    Czech Academy of Sciences Publication Activity Database

    Sumrandee, C.; Hirunkanokpun, S.; Doornbos, K.; Kitthawee, S.; Baimai, V.; Grubhoffer, Libor; Trinachartvanit, W.; Ahantarig, A.

    2014-01-01

    Roč. 5, č. 6 (2014), s. 632-640 ISSN 1877-959X Institutional support: RVO:60077344 Keywords : Tick * Rickettsia spp. * Amblyomma varanense * Amblyomma helvolum * Snake * Thailand Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.718, year: 2014

  16. Pathogenic potential of a Costa Rican strain of 'Candidatus Rickettsia amblyommii' in guinea pigs (Cavia porcellus) and protective immunity against Rickettsia rickettsii.

    Science.gov (United States)

    Rivas, Juan J; Moreira-Soto, Andrés; Alvarado, Gilberth; Taylor, Lizeth; Calderón-Arguedas, Olger; Hun, Laya; Corrales-Aguilar, Eugenia; Morales, Juan Alberto; Troyo, Adriana

    2015-09-01

    'Candidatus Rickettsia amblyommii' is a spotted fever group rickettsia that is not considered pathogenic, although there is serologic evidence of possible infection in animals and humans. The aim of this study was to evaluate the pathogenic potential of a Costa Rican strain of 'Candidatus R. amblyommii' in guinea pigs and determine its capacity to generate protective immunity against a subsequent infection with a local strain of Rickettsia rickettsii isolated from a human case. Six guinea pigs were inoculated with 'Candidatus R. amblyommii' strain 9-CC-3-1 and two controls with cell culture medium. Health status was evaluated, and necropsies were executed at days 2, 4, and 13. Blood and tissues were processed by PCR to detect the gltA gene, and end titers of anti-'Candidatus R. amblyommii' IgG were determined by indirect immunofluorescence. To evaluate protective immunity, another 5 guinea pigs were infected with 'Candidatus R. amblyommii' (IGPs). After 4 weeks, these 5 IGPs and 3 controls (CGPs) were inoculated with pathogenic R. rickettsii. Clinical signs and titers of anti-Rickettsia IgG were determined. IgG titers reached 1:512 at day 13 post-infection with 'Candidatus R. amblyommii'. On day 2 after inoculation, two guinea pigs had enlarged testicles and 'Candidatus R. amblyommii' DNA was detected in testicles. Histopathology confirmed piogranulomatous orchitis with perivascular inflammatory infiltrate in the epididymis. In the protective immunity assay, anti-Rickettsia IgG end titers after R. rickettsii infection were lower in IGPs than in CGPs. IGPs exhibited only transient fever, while CGP showed signs of severe disease and mortality. R. rickettsii was detected in testicles and blood of CGPs. Results show that the strain 9-CC-3-1 of 'Candidatus R. amblyommii' was able to generate pathology and an antibody response in guinea pigs. Moreover, its capacity to generate protective immunity against R. rickettsii may modulate the epidemiology and severity of Rocky

  17. Bacteria of the genus Rickettsia in ticks (Acari: Ixodidae) collected from birds in Costa Rica.

    Science.gov (United States)

    Ogrzewalska, Maria; Literák, Ivan; Capek, Miroslav; Sychra, Oldřich; Calderón, Víctor Álvarez; Rodríguez, Bernardo Calvo; Prudencio, Carlos; Martins, Thiago F; Labruna, Marcelo B

    2015-06-01

    The aim of this study was to document the presence of Rickettsia spp. in ticks parasitizing wild birds in Costa Rica. Birds were trapped at seven locations in Costa Rica during 2004, 2009, and 2010; then visually examined for the presence of ticks. Ticks were identified, and part of them was tested individually for the presence of Rickettsia spp. by polymerase chain reaction (PCR) using primers targeting fragments of the rickettsial genes gltA and ompA. PCR products were DNA-sequenced and analyzed in BLAST to determine similarities with previously reported rickettsial agents. A total of 1878 birds were examined, from which 163 birds (9%) were infested with 388 ticks of the genera Amblyomma and Ixodes. The following Amblyomma (in decreasing order of abundance) were found in immature stages (larvae and nymphs): Amblyomma longirostre, Amblyomma calcaratum, Amblyomma coelebs, Amblyomma sabanerae, Amblyomma varium, Amblyomma maculatum, and Amblyomma ovale. Ixodes ticks were represented by Ixodes minor and two unclassified species, designated here as Ixodes sp. genotype I, and Ixodes sp. genotype II. Twelve of 24 tested A. longirostre ticks were found to be infected with 'Candidatus Rickettsia amblyommii', and 2 of 4 A. sabanerae were found to be infected with Rickettsia bellii. Eight of 10 larval Ixodes minor were infected with an endosymbiont (a novel Rickettsia sp. agent) genetically related to the Ixodes scapularis endosymbiont. No rickettsial DNA was found in A. calcaratum, A. coelebs, A. maculatum, A. ovale, A. varium, Ixodes sp. I, and Ixodes sp. II. We report the occurrence of I. minor in Costa Rica for the first time and a number of new bird host-tick associations. Moreover, 'Candidatus R. amblyommii' and R. bellii were found in A. longirostre and A. sabanerae, respectively, in Costa Rica for the first time. Copyright © 2015 Elsevier GmbH. All rights reserved.

  18. Neorickettsia risticii, Rickettsia sp. and Bartonella sp. in Tadarida brasiliensis bats from Buenos Aires, Argentina.

    Science.gov (United States)

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

    2017-06-01

    Bats are potential reservoirs of many vector-borne bacterial pathogens. The aim of the present study was to detect species of Anaplasma, Ehrlichia, Neorickettsia, Rickettsia, Borrelia and Bartonella in Brazilian free-tailed bats (Tadarida brasiliensis, Molossidae) from Buenos Aires city, Argentina. Between 2012 and 2013, 61 T. brasiliensis from urban areas of Buenos Aires city were studied. The samples were molecularly screened by PCR and sequencing. Five bats (8.2%) were positive to Neorickettsia risticii, one (1.6%) was positive to Rickettsia sp. and three bats (4.9%) to Bartonella sp. For molecular characterization, the positive samples were subjected to amplification and sequencing of a fragment of p51 gene for N. risticii, a fragment of citrate synthase gene (gltA) for Rickettsia genus and a fragment of gltA for Bartonella genus. Phylogenetic tree was constructed using the maximum-likelihood method. Phylogenetic analysis of N. risticii detect in our study revealed that it relates to findings in the USA West Coast; Rickettsia sp. detected is phylogenetically within R. bellii group, which also includes many other Rickettsia endosymbionts of insects; and Bartonella sp. found is related to various Bartonella spp. described in Vespertilionidae bats, which are phylogenetically related to Molossidae. Our results are in accordance to previous findings, which demonstrate that insectivorous bats could be infected with vector-borne bacteria representing a potential risk to public health. Future research is necessary to clarify the circulation of these pathogens in bats from Buenos Aires. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Pesquisa de Rickettsia spp em carrapatos Amblyomma cajennense e Amblyomma dubitatum no Estado de São Paulo Survey of Rickettsia spp in the ticks Amblyomma cajennense and Amblyomma dubitatum in the State of São Paulo

    Directory of Open Access Journals (Sweden)

    Richard Campos Pacheco

    2009-06-01

    Full Text Available Foi pesquisada a presença de riquétsias em 3.545 carrapatos Amblyomma cajennense e 2.666 Amblyomma dubitatum. Através do teste de hemolinfa, reação em cadeia pela polimerase e isolamento de rickettsia em cultivo celular, todos os Amblyomma cajennense foram negativos, sendo que 634 (23,8% Amblyomma dubitatum mostraram-se infectados com Rickettsia bellii.The presence of rickettsial infection was surveyed in 3,545 Amblyomma cajennense ticks and 2,666 Amblyomma dubitatum ticks. Using the hemolymph test, polymerase chain reaction and isolation of Rickettsia in cell cultures, all of the Amblyomma cajennense were negative, whereas 634 (23.8% of the Amblyomma dubitatum ticks were shown to be infected with Rickettsia bellii.

  20. Spotted fever group Rickettsia in Amblyomma dubitatum tick from the urban area of Campo Grande, Mato Grosso do Sul, Brazil.

    Science.gov (United States)

    Matias, Jaqueline; Garcia, Marcos Valério; Cunha, Rodrigo Casquero; Aguirre, André de Abreu Rangel; Barros, Jacqueline Cavalvante; Csordas, Bárbara Guimarães; Andreotti, Renato

    2015-03-01

    Rickettsia infection of each tick was evaluated by the hemolymph test and polymerase chain reaction (PCR) targeting gltA and ompA genes. All hemolymph tests were negative and PCR of one A. dubitatum detected both Rickettsia genes. Sequence of ompA exhibited a 99% identity with Rickettsia parkeri and R. africae and a 98% identity with R. sibirica. Rickettsia of the spotted fever group in A. dubitatum is described for the first time in an urban area within the municipality of Campo Grande in the state of Mato Grosso do Sul (MS), Brazil. This finding reinforces the importance of more detailed studies to determine the role of A. dubitatum in the transmission of spotted fever agents. Copyright © 2014 Elsevier GmbH. All rights reserved.

  1. Molecular Pathogenesis of Rickettsioses and Development of Novel Anti-Rickettsia Treatment by Comginatorial Peptide-Based Libraries

    National Research Council Canada - National Science Library

    Walker, David H; Olano, Juan P

    2005-01-01

    ...) library and challenge with R. prowazekii, R. rickettsii, and 0. tsutsugamushi; 2) To determine the role of NF-KB, cytokines, ROS and NO in intracellular killing of rickettsia-infected monolayers containing adapteins and 3...

  2. The genome sequence of Rickettsia felis identifies the first putative conjugative plasmid in an obligate intracellular parasite.

    OpenAIRE

    Hiroyuki Ogata; Patricia Renesto; Stéphane Audic; Catherine Robert; Guillaume Blanc; Pierre-Edouard Fournier; Hugues Parinello; Jean-Michel Claverie; Didier Raoult

    2005-01-01

    We sequenced the genome of Rickettsia felis, a flea-associated obligate intracellular alpha-proteobacterium causing spotted fever in humans. Besides a circular chromosome of 1,485,148 bp, R. felis exhibits the first putative conjugative plasmid identified among obligate intracellular bacteria. This plasmid is found in a short (39,263 bp) and a long (62,829 bp) form. R. felis contrasts with previously sequenced Rickettsia in terms of many other features, including a number of transposases, sev...

  3. Serological and molecular detection of spotted fever group Rickettsia in a group of pet dogs from Luanda, Angola.

    Science.gov (United States)

    Barradas, Patrícia F; Vilhena, Hugo; Oliveira, Ana Cristina; Granada, Sara; Amorim, Irina; Ferreira, Paula; Cardoso, Luís; Gärtner, Fátima; de Sousa, Rita

    2017-05-31

    Infections with tick-borne rickettsiae can cause diseases well known in humans but still not so well characterized in dogs. Susceptibility to infection depends on the virulence of Rickettsia spp. and only a few of them have been described to cause disease in dogs. The aim of this study was to investigate the exposure to Rickettsia spp. among a group of pet dogs from Luanda, Angola. Out of 103 dogs included in the study, 62 (60.2%) were infested with ticks. Plasma specimens tested for serology by an immunofluorescence assay (IFA) revealed that six (5.8%) dogs had detectable immunoglobulin G (IgG) antibodies to spotted fever group Rickettsia (SFGR), with endpoint titers of 64 for two dogs, 128 for three dogs and 1024 for one dog. From the seropositive group of dogs, five (83%) of them were males, with their age ranging from 1 to 8 years old. Among the seropositive dogs, four (66.7%) were parasitized with ticks and no breed (or cross) was found to be associated with specific antibodies. Rickettsia spp. DNA was detected by nested-polymerase chain reaction (PCR) in two (1.9%) dogs that were found to be seronegative. Seroprevalence and molecular detection of Rickettsia spp. infection in this group of pet dogs from Luanda is low compared with other studies performed in the same type of hosts in other areas. Although many dogs were parasitized with ticks, a low prevalence of Rickettsia spp. could be related with the hypothesis of a low rickettsial prevalence in the infesting ticks. This study provides evidence that dogs in Luanda are exposed to Rickettsia spp., but further studies are needed to better characterize the bacterial infections in dogs and in their ectoparasites.

  4. Rickettsia in Synanthropic and Domestic Animals and Their Hosts from Two Areas of Low Endemicity for Brazilian Spotted Fever in the Eastern Region of Minas Gerais, Brazil

    Science.gov (United States)

    Milagres, Bruno S.; Padilha, Amanda F.; Barcelos, Rafael M.; Gomes, Gabriel G.; Montandon, Carlos E.; Pena, Dárlen C. H.; Nieri Bastos, Fernanda A.; Silveira, Iara; Pacheco, Richard; Labruna, Marcelo B.; Bouyer, Donald H.; Freitas, Renata N.; Walker, David H.; Mafra, Cláudio L.; Galvao, Márcio A. M.

    2010-01-01

    The aim of this study was to understand the current epidemiology of rickettsial diseases in two rickettsial-endemic regions in Brazil. In the municipalities of Pingo D'Agua and Santa Cruz do Escalvado, among serum samples obtained from horses and dogs, reactivity by immunofluorescent assay against spotted fever group rickettsiae was verified. In some serum samples from opossums (Didelphis aurita) captured in Santa Cruz do Escalvado, serologic response against rickettsiae was also verified. Polymerase chain reaction identified rickettsiae only in ticks and fleas obtained in Santa Cruz do Escalvado. Rickettsiae in samples had 100% sequence homology with Rickettsia felis. These results highlight the importance of marsupials in maintenance of the sylvatic cycle of rickettsial disease and potential integration with the domestic cycle. Our data also support the importance of horses and dogs as sentinels in monitoring circulation of rickettsiae in an urban area. PMID:21118939

  5. First report of Rickettsia raoultii and R. slovaca in Melophagus ovinus, the sheep ked

    Directory of Open Access Journals (Sweden)

    Dan Liu

    2016-11-01

    Full Text Available Abstract Background Melophagus ovinus (Diptera: Hippoboscidae, a hematophagous ectoparasite, is mainly found in Europe, Northwestern Africa, and Asia. This wingless fly infests sheep, rabbits, and red foxes, and causes inflammation, wool loss and skin damage. Furthermore, this parasite has been shown to transmit diseases, and plays a role as a vector. Herein, we investigated the presence of various Rickettsia species in M. ovinus. Methods In this study, a total of 95 sheep keds were collected in Kuqa County and Alaer City southern region of Xinjiang Uygur Autonomous Region, northwestern China. First, collected sheep keds were identified on the species level using morphological keys and molecular methods based on a fragment of the 18S ribosomal DNA gene (18S rDNA. Thereafter, to assess the presence of rickettsial DNA in sheep keds, the DNA of individual samples was screened by PCR based on six Rickettsia-specific gene fragments originating from six genes: the 17-kilodalton antigen gene (17-kDa, 16S rRNA gene (rrs, surface cell antigen 4 gene (sca4, citrate synthase gene (gltA, and outer membrane protein A and B genes (ompA and ompB. The amplified products were confirmed by sequencing and BLAST analysis ( https://blast.ncbi.nlm.nih.gov/Blast.cgi?PROGRAM=blastn&PAGE_TYPE=BlastSearch&LINK_LOC=blasthome . Results According to its morphology and results of molecular analysis, the species was identified as Melophagus ovinus, with 100% identity to M. ovinus from St. Kilda, Australia (FN666411. DNA of Rickettsia spp. were found in 12 M. ovinus samples (12.63%, 12/95. Rickettsia raoultii and R. slovaca were confirmed based on phylogenetic analysis, although the genetic markers of these two rickettsial agents amplified in this study showed molecular diversity. Conclusions This is the first report of R. raoultii and R. slovaca DNA in M. ovinus. Rickettsia slovaca was found for the first time around the Taklimakan Desert located in China. This finding

  6. An anomalous type IV secretion system in Rickettsia is evolutionarily conserved.

    Directory of Open Access Journals (Sweden)

    Joseph J Gillespie

    Full Text Available Bacterial type IV secretion systems (T4SSs comprise a diverse transporter family functioning in conjugation, competence, and effector molecule (DNA and/or protein translocation. Thirteen genome sequences from Rickettsia, obligate intracellular symbionts/pathogens of a wide range of eukaryotes, have revealed a reduced T4SS relative to the Agrobacterium tumefaciens archetype (vir. However, the Rickettsia T4SS has not been functionally characterized for its role in symbiosis/virulence, and none of its substrates are known.Superimposition of T4SS structural/functional information over previously identified Rickettsia components implicate a functional Rickettsia T4SS. virB4, virB8 and virB9 are duplicated, yet only one copy of each has the conserved features of similar genes in other T4SSs. An extraordinarily duplicated VirB6 gene encodes five hydrophobic proteins conserved only in a short region known to be involved in DNA transfer in A. tumefaciens. virB1, virB2 and virB7 are newly identified, revealing a Rickettsia T4SS lacking only virB5 relative to the vir archetype. Phylogeny estimation suggests vertical inheritance of all components, despite gene rearrangements into an archipelago of five islets. Similarities of Rickettsia VirB7/VirB9 to ComB7/ComB9 proteins of epsilon-proteobacteria, as well as phylogenetic affinities to the Legionella lvh T4SS, imply the Rickettsiales ancestor acquired a vir-like locus from distantly related bacteria, perhaps while residing in a protozoan host. Modern modifications of these systems likely reflect diversification with various eukaryotic host cells.We present the rvh (Rickettsiales vir homolog T4SS, an evolutionary conserved transporter with an unknown role in rickettsial biology. This work lays the foundation for future laboratory characterization of this system, and also identifies the Legionella lvh T4SS as a suitable genetic model.

  7. “Candidatus Rickettsia andeanae” en Amblyomma tigrinum, San Luis, Argentina

    Directory of Open Access Journals (Sweden)

    Gabriel CICUTTIN

    2016-11-01

    Full Text Available El objetivo del estudio fue detectar especies del género Rickettsia en garrapatas de la especie Amblyomma tigrinum colectadas sobre carnívoros domésticos y en sangre de caninos domésticos de la provincia de San Luis (Argentina. Entre 2013 y 2015 se colectaron 56 garrapatas adultas de la especie A. tigrinum sobre caninos y felinos domésticos, y se obtuvieron 65 muestras sanguíneas de caninos. Tres garrapatas resultaron positivas mediante la amplificación de un fragmento del espacio intergénico 23S-5S ARNr del género Rickettsia, lográndose secuenciar uno de los productos positivos. La muestra positiva secuenciada también resultó positiva por PCRs de los fragmentos de los genes gltA y ompA. Las secuencias obtenidas resultaron tener una identidad del 100 % de identidad con “Candidatus Rickettsia andeanae”. Todas las muestras sanguíneas resultaron negativas. “Ca. R. andeanae” no ha sido asociada con enfermedad en humanos o animales, sin embargo, es necesario realizar nuevas investigaciones para lograr un mayor conocimiento del riesgo potencial de transmisión de rickettsiosis en la región. SUMMARY. “Candidatus Rickettsia andeanae” in Amblyomma tigrinum ticks from San Luis (Argentina. The aim of this study was to detect species of Rickettsia in Amblyomma tigrinum ticks collected from domestic carnivores and blood of domestic dogs of San Luis (Argentina. Between 2013 and 2015, 56 adults of A. tigrinum from dogs and cats and 65 blood from dogs were collected. Three ticks were positive by amplification of a 23S-5S rRNA fragment, and the sequence of one of the positive products was obtained. The positive sample sequenced was positive by PCRs of fragments of genes gltA and ompA. The sequences obtained were 100% identical with "Candidatus Rickettsia andeanae". All blood samples were negative. “Ca. R. andeanae” has not been associated with disease in humans or animals; however, further research is necessary to achieve greater

  8. First report of Rickettsia raoultii and R. slovaca in Melophagus ovinus, the sheep ked.

    Science.gov (United States)

    Liu, Dan; Wang, Yuan-Zhi; Zhang, Huan; Liu, Zhi-Qiang; Wureli, Ha-Zi; Wang, Shi-Wei; Tu, Chang-Chun; Chen, Chuang-Fu

    2016-11-25

    Melophagus ovinus (Diptera: Hippoboscidae), a hematophagous ectoparasite, is mainly found in Europe, Northwestern Africa, and Asia. This wingless fly infests sheep, rabbits, and red foxes, and causes inflammation, wool loss and skin damage. Furthermore, this parasite has been shown to transmit diseases, and plays a role as a vector. Herein, we investigated the presence of various Rickettsia species in M. ovinus. In this study, a total of 95 sheep keds were collected in Kuqa County and Alaer City southern region of Xinjiang Uygur Autonomous Region, northwestern China. First, collected sheep keds were identified on the species level using morphological keys and molecular methods based on a fragment of the 18S ribosomal DNA gene (18S rDNA). Thereafter, to assess the presence of rickettsial DNA in sheep keds, the DNA of individual samples was screened by PCR based on six Rickettsia-specific gene fragments originating from six genes: the 17-kilodalton antigen gene (17-kDa), 16S rRNA gene (rrs), surface cell antigen 4 gene (sca4), citrate synthase gene (gltA), and outer membrane protein A and B genes (ompA and ompB). The amplified products were confirmed by sequencing and BLAST analysis ( https://blast.ncbi.nlm.nih.gov/Blast.cgi?PROGRAM=blastn&PAGE_TYPE=BlastSearch&LINK_LOC=blasthome ). According to its morphology and results of molecular analysis, the species was identified as Melophagus ovinus, with 100% identity to M. ovinus from St. Kilda, Australia (FN666411). DNA of Rickettsia spp. were found in 12 M. ovinus samples (12.63%, 12/95). Rickettsia raoultii and R. slovaca were confirmed based on phylogenetic analysis, although the genetic markers of these two rickettsial agents amplified in this study showed molecular diversity. This is the first report of R. raoultii and R. slovaca DNA in M. ovinus. Rickettsia slovaca was found for the first time around the Taklimakan Desert located in China. This finding extends the geographical range of spotted fever group

  9. Molecular detection of Rickettsia rhipicephali and other spotted fever group Rickettsia species in Amblyomma ticks infesting wild birds in the state of Minas Gerais, Brazil.

    Science.gov (United States)

    Zeringóta, Viviane; Maturano, Ralph; Luz, Hermes Ribeiro; Senra, Tatiane Oliveira Souza; Daemon, Erik; Faccini, João Luiz Horacio; McIntosh, Douglas

    2017-01-01

    The current study evaluated parasitism of wild birds by ticks in a fragment of Atlantic Forest in the state of Minas Gerais, Brazil, and examined the ticks for rickettsial agents. Birds were captured during 2014 and 2015 and ticks were identified by sequencing fragments of the 16S and 12S ribosomal DNA. Among 260 birds representing 19 families and 52 species, a total of 69 (26.5%) were found to be infested by larvae (LL) and/or nymphs (NN) of Amblyomma longirostre (Koch, 1844) (45 LL, 4 NN), Amblyomma calcaratum Neumann, 1899 (9 LL, 15 NN), Amblyomma nodosum Neumann, 1899 (2 NN), Amblyomma parkeri Fonseca and Aragão, 1952 (21 LL), Amblyomma sp. haplotype Nazaré (77 LL), and Haemaphysalis leporispalustris (Packard, 1869) (17 LL, 1 NN). The use of PCR and sequencing of the rickettsial genes gltA, htrA, ompA and ompB, revealed the presence of "Candidatus Rickettsia amblyommii" in A. longirostre (13/49; 26%) and Rickettsia parkeri (strain ApPR) in both A. parkeri (1/21; 5%) and haplotype Nazaré (42/77; 55%) ticks. In addition, we detected Rickettsia rhipicephali in 31 (40%) of the 77 haplotype Nazaré ticks. This is the first record of this rickettsial agent in a species of the genus Amblyomma. The pathogenic potential of this bacterium is undetermined, but the unprecedented association with Amblyomma ticks may represent a cause for concern for public and/or animal health. Copyright © 2016 Elsevier GmbH. All rights reserved.

  10. Rickettsia amblyommatis infecting ticks and exposure of domestic dogs to Rickettsia spp. in an Amazon-Cerrado transition region of northeastern Brazil.

    Science.gov (United States)

    Costa, Francisco B; da Costa, Andréa P; Moraes-Filho, Jonas; Martins, Thiago F; Soares, Herbert S; Ramirez, Diego G; Dias, Ricardo A; Labruna, Marcelo B

    2017-01-01

    This study was performed in Maranhão state, a transition area two Brazilian biomes, Amazon and Cerrado. During 2011-2013, 1,560 domestic dogs were sampled for collection of serum blood samples and ticks in eight counties (3 within the Amazon and 5 within the Cerrado). A total of 959 ticks were collected on 150 dogs (9.6%). Rhipicephalus sanguineus sensu lato (s.l.) was the most abundant tick (68% of all collected specimens), followed by Amblyomma cajennense sensu lato (s.l.) (12.9%), Amblyomma parvum (9.2%), and Amblyomma ovale (5.2%). Other less abundant species (Cerrado area, and A. cajennense s.s. from pigs in an Amazon area revealed R. amblyommatis infecting only the A. cajennense s.s. ticks. Serological analysis of the 1,560 canine blood samples revealed 12.6% canine seroreactivity to Rickettsia spp., with the highest specific seroreactivity rate (10.2%) for R. amblyommatis. Endpoint titers to R. amblyommatis were significantly higher than those for the other Rickettsia antigens, suggesting that most of the seroreactive dogs were exposed to R. amblyommatis-infected ticks. Highest canine seroreactivity rates per locality (13.1-30.8%) were found in Amazon biome, where A. cajennense s.s. predominated. Lowest seroreactivity rates (1.9-6.5%) were found in Cerrado localities that were further from the Amazon, where A. sculptum predominated. Multivariate analyses revealed that canine seroreactivity to Rickettsia spp. or R. amblyommatis was statistically associated with rural dogs, exposed to Amblyomma ticks.

  11. Detection of Babesia Sp. EU1 and members of spotted fever group rickettsiae in ticks collected from migratory birds at Curonian Spit, North-Western Russia.

    Science.gov (United States)

    Movila, Alexandru; Reye, Anna L; Dubinina, Helen V; Tolstenkov, Oleg O; Toderas, Ion; Hübschen, Judith M; Muller, Claude P; Alekseev, Andrey N

    2011-01-01

    To reveal the prevalence of spotted fever group (SFG) rickettsiae and Babesia sp. in Ixodes ricinus (L.) ticks from migratory birds, 236 specimens represented 8 species of Passeriformes and were collected at Curonian Spit in Kaliningrad enclave of North-Western Russia. The ticks (total 126) being detached from four bird species, Turdus philomelos, Fringilla coelebs, Parus major, and Sturnus vulgaris, were investigated by PCR using the primers Rp CS.877p/Rp CS.1258n for the detection of Rickettsia and BJ1/BN2 for Babesia spp. Babesia spp. were detected in 2 of 126 (1.6%) ticks. The partial sequence of 18S rDNA had 100% similarity to human pathogenic Babesia sp. EU1. The SFG rickettsiae were detected in 19 of 126 (15.1%) ticks collected from the above-mentioned bird species. BLAST analysis of SFG rickettsia gltA assigned sequences to human pathogenic Rickettsia helvetica (10.3%), Rickettsia monacensis (3.9%), and Rickettsia japonica (0.8%) with 98%-100% sequence similarity. The SFG rickettsiae and Babesia sp. EU1 in ticks collected from the passerines in Russia were detected for the first time. The survey indicates that migratory birds may become a reservoir for Babesia spp. and SFG rickettsiae. Future investigations need to characterize the role of birds in the epidemiology of these human pathogens in the region.

  12. Outbreak of Rickettsia africae infections in participants of an adventure race in South Africa.

    Science.gov (United States)

    Fournier, P E; Roux, V; Caumes, E; Donzel, M; Raoult, D

    1998-08-01

    African tick-bite fever, caused by Rickettsia africae and transmitted by Amblyomma ticks, is an emerging rickettsiosis in southern Africa. Because of increased tourism to this area, several cases in tourists have been reported recently. We report 13 cases of R. africae infection diagnosed in France that occurred in competitors returning from an adventure race in South Africa and compare our data with previously reported findings. Most of our patients presented with fever, headache, multiple inoculation eschars, and regional lymphadenopathies, but only 15.4% had a cutaneous rash. Diagnosis was confirmed either by isolation of R. africae from an eschar biopsy specimen or by serological methods, including cross-adsorption between R. africae and Rickettsia conorii. The purpose of this study was to raise physicians' awareness of R. africae infections in an attempt to facilitate the rapid diagnosis and treatment of imported African tick-bite fever in developed countries.

  13. Evidence of spotted fever group rickettsiae in state of Rio de Janeiro, Brazil

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    ROZENTAL Tatiana

    2002-01-01

    Full Text Available Ticks were obtained from dogs from February to September of 1999 at weekly intervals, in the County of Piraí, State of Rio de Janeiro. Four hundred seventy four ixodids were taxonomically identified, 103 Amblyomma cajennense, seven Amblyomma ovale, 209 Rhipicephalus sanguineus, and 155 Amblyomma sp. An hemolymph test associated with Giemsa's stain revealed two specimens in 163 ticks tested (R. sanguineus and Amblyomma sp, containing rickettsia-like organisms. Direct immunofluorescence verified the presence of spotted fever group rickettsia in one specimen of R. sanguineus. Considering the limited information on rickettsiosis in Brazil, principally in relation to the vectors involved in perpetuating it in foci, these preliminary results give us an idea on the importance of infection in ticks, allowing to expand our knowledge on this zoonosis.

  14. Molecular Detection of Rickettsia africae in Amblyomma variegatum Collected from Sudan.

    Science.gov (United States)

    Nakao, Ryo; Qiu, Yongjin; Salim, Bashir; Hassan, Shawgi Mohamed; Sugimoto, Chihiro

    2015-05-01

    Despite the increasing awareness of the importance of emerging vector-borne diseases, human tick-borne diseases, particularly rickettsial infections, are overlooked, especially in the countries such as Sudan with limited resources to perform molecular-based surveys. This study aimed at detection and genetic characterization of Rickettsia spp. in ticks collected from Sudan. The samples were first screened for the presence of rickettsial agents by gltA real-time PCR and subsequently characterized by gltA and ompA PCR and size-based multispacer typing. The results demonstrated the wide distribution of Rickettsia africae and/or closely related species across Sudan. The results of this report highlight the need for careful consideration of rickettsial infections in patients with nonmalarial febrile illness in this country. Nationwide surveillance on ticks associated with human rickettsial infections in Sudan is warranted.

  15. Orientia, rickettsia, and leptospira pathogens as causes of CNS infections in Laos: a prospective study.

    Science.gov (United States)

    Dittrich, Sabine; Rattanavong, Sayaphet; Lee, Sue J; Panyanivong, Phonepasith; Craig, Scott B; Tulsiani, Suhella M; Blacksell, Stuart D; Dance, David A B; Dubot-Pérès, Audrey; Sengduangphachanh, Amphone; Phoumin, Phonelavanh; Paris, Daniel H; Newton, Paul N

    2015-02-01

    Scrub typhus (caused by Orientia tsutsugamushi), murine typhus (caused by Rickettsia typhi), and leptospirosis are common causes of febrile illness in Asia; meningitis and meningoencephalitis are severe complications. However, scarce data exist for the burden of these pathogens in patients with CNS disease in endemic countries. Laos is representative of vast economically poor rural areas in Asia with little medical information to guide public health policy. We assessed whether these pathogens are important causes of CNS infections in Laos. Between Jan 10, 2003, and Nov 25, 2011, we enrolled 1112 consecutive patients of all ages admitted with CNS symptoms or signs requiring a lumbar puncture at Mahosot Hospital, Vientiane, Laos. Microbiological examinations (culture, PCR, and serology) targeted so-called conventional bacterial infections (Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, S suis) and O tsutsugamushi, Rickettsia typhi/Rickettsia spp, and Leptospira spp infections in blood or cerebrospinal fluid (CSF). We analysed and compared causes and clinical and CSF characteristics between patient groups. 1051 (95%) of 1112 patients who presented had CSF available for analysis, of whom 254 (24%) had a CNS infection attributable to a bacterial or fungal pathogen. 90 (35%) of these 254 infections were caused by O tsutsugamushi, R typhi/Rickettsia spp, or Leptospira spp. These pathogens were significantly more frequent than conventional bacterial infections (90/1051 [9%] vs 42/1051 [4%]; pLaos. Antibiotics, such as tetracyclines, needed for the treatment of murine typhus and scrub typhus, are not routinely advised for empirical treatment of CNS infections. These severely neglected infections represent a potentially large proportion of treatable CNS disease burden across vast endemic areas and need more attention. Wellcome Trust UK. Copyright © 2015 Dittrich et al. Open Access article published under the terms of CC BY. Published by .. All

  16. First report of Rickettsia raoultii and R. slovaca in Melophagus ovinus, the sheep ked

    OpenAIRE

    Liu, Dan; Wang, Yuan-Zhi; Zhang, Huan; Liu, Zhi-Qiang; Wureli, Ha-zi; Wang, Shi-Wei; Tu, Chang-Chun; Chen, Chuang-Fu

    2016-01-01

    Background Melophagus ovinus (Diptera: Hippoboscidae), a hematophagous ectoparasite, is mainly found in Europe, Northwestern Africa, and Asia. This wingless fly infests sheep, rabbits, and red foxes, and causes inflammation, wool loss and skin damage. Furthermore, this parasite has been shown to transmit diseases, and plays a role as a vector. Herein, we investigated the presence of various Rickettsia species in M. ovinus. Methods In this study, a total of 95 sheep keds were collected in Kuqa...

  17. Arsenophonus nasoniae and Rickettsiae Infection of Ixodes ricinus Due to Parasitic Wasp Ixodiphagus hookeri.

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    Monika Bohacsova

    Full Text Available Arsenophonus nasoniae, a male-killing endosymbiont of chalcid wasps, was recently detected in several hard tick species. Following the hypothesis that its presence in ticks may not be linked to the direct occurrence of bacteria in tick's organs, we identified A. nasoniae in wasps emerging from parasitised nymphs. We confirmed that 28.1% of Ixodiphagus hookeri wasps parasitizing Ixodes ricinus ticks were infected by A. nasoniae. Moreover, in examined I. ricinus nymphs, A. nasoniae was detected only in those, which were parasitized by the wasp. However, in part of the adult wasps as well as in some ticks that contained wasp's DNA, we did not confirm A. nasoniae. We also found, that in spite of reported male-killing, some newly emerged adult wasp males were also infected by A. nasoniae. Additionally, we amplified the DNA of Rickettsia helvetica and Rickettsia monacensis (known to be Ixodes ricinus-associated bacteria in adult parasitoid wasps. This may be related either with the digested bacterial DNA in wasp body lumen or with a role of wasps in circulation of rickettsiae among tick vectors.

  18. Tick- and fly-borne bacteria in ungulates: the prevalence of Anaplasma phagocytophilum, haemoplasmas and rickettsiae in water buffalo and deer species in Central Europe, Hungary.

    Science.gov (United States)

    Hornok, Sándor; Sugár, László; Fernández de Mera, Isabel G; de la Fuente, José; Horváth, Gábor; Kovács, Tibor; Micsutka, Attila; Gönczi, Enikő; Flaisz, Barbara; Takács, Nóra; Farkas, Róbert; Meli, Marina L; Hofmann-Lehmann, Regina

    2018-03-20

    Hunting constitutes an important industry in Europe. However, data on the prevalence of vector-borne bacteria in large game animal species are lacking from several countries. Blood or spleen samples (239 and 270, respectively) were taken from red, fallow and roe deer, as well as from water buffaloes, mouflons and wild boars in Hungary, followed by DNA extraction and molecular analyses for Anaplasma phagocytophilum, haemoplasmas and rickettsiae. Based on blood samples, the prevalence rate of A. phagocytophilum infection was significantly higher in red deer (97.9%) than in fallow deer (72.7%) and roe deer (60%), and in all these compared to mouflons (6.3%). In addition, 39.2% of the spleen samples from wild boars were PCR positive for A. phagocytophilum, but none of the buffalos. Based on blood samples, the prevalence rates of both Mycoplasma wenyonii (Mw) and 'Candidatus M. haemobos' (CMh) infections were significantly higher in buffaloes (Mw: 91.2%; CMh: 73.3%) than in red deer (Mw: 64.6%; CMh: 45.8%), and in both of them compared to fallow deer (Mw: 30.3%; CMh: 9.1%) and roe deer (Mw: 20%; CMh: 1.5%). The prevalence of Mw and CMh infection significantly correlated with the body sizes of these hosts. Furthermore, Mw was significantly more prevalent than CMh in buffaloes, red and roe deer. Mycoplasma ovis was detected in mouflons, M. suis in wild boars, R. helvetica in one fallow deer and one mouflon, and an unidentified Rickettsia sp. in a fallow deer. Forest-dwelling game animal species were found to be important carriers of A. phagocytophilum. In contrast, animals grazing grassland (i.e. buffaloes) were less likely to get infected with this Ixodes ricinus-borne pathogen. Water buffaloes, deer species, mouflons and wild boars harbored haemoplasmas that may affect domestic ungulates. Evaluated animals with larger body size had significantly higher prevalence of infection with haemoplasmas compared to smaller deer species. The above host species rarely carried

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

    Science.gov (United States)

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

    2006-01-01

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

  20. First molecular evidence of Anaplasma ovis and Rickettsia spp. in keds (Diptera: Hippoboscidae) of sheep and wild ruminants.

    Science.gov (United States)

    Hornok, Sándor; de la Fuente, José; Biró, Nóra; Fernández de Mera, Isabel G; Meli, Marina L; Elek, Vilmos; Gönczi, Eniko; Meili, Theres; Tánczos, Balázs; Farkas, Róbert; Lutz, Hans; Hofmann-Lehmann, Regina

    2011-10-01

    To evaluate the presence of rickettsial agents in hippoboscid flies with molecular methods, 81 sheep keds (Melophagus ovinus) were collected from 23 sheep, 144 deer keds (Lipoptena cervi) were caught in the environment, and a further 463 and 59 individuals of the latter species were obtained from fresh carcasses of 29 red deer and 17 roe deer, respectively. DNA was extracted individually or in pools. Anaplasma ovis was demonstrated in all examined sheep keds, and from one pool of free-living deer keds. Rickettsia helvetica or other, unidentified rickettsiae were also present in one pool of sheep keds, and in four pools of deer keds from both red deer and roe deer. This is the first account of polymerase chain reaction positivity of hippoboscid flies for A. ovis and rickettsiae. These results raise the possibility that-apart from cattle and roe deer as already reported-sheep and red deer might also play a reservoir role in the epidemiology of rickettsioses.

  1. Rickettsia amblyommii infecting Amblyomma auricularium ticks in Pernambuco, northeastern Brazil: isolation, transovarial transmission, and transstadial perpetuation.

    Science.gov (United States)

    Saraiva, Danilo G; Nieri-Bastos, Fernanda A; Horta, Maurício C; Soares, Herbert S; Nicola, Patricia A; Pereira, Luiz Cezar M; Labruna, Marcelo B

    2013-09-01

    This study investigated rickettsial infection in Amblyomma auricularium ticks from the state of Pernambuco, northeastern Brazil. An engorged female of A. auricularium collected from a skunk (Conepatus semistriatus) was sent alive to the laboratory, where the female was found through molecular analysis to be infected by Rickettsia amblyommii. This engorged female oviposited, and its offspring was reared through three consecutive generations, always using tick-naïve rabbits to feed the ticks. PCR performed on five egg pools, 10 larvae, 10 nymphs, and 10 adults of each of the three generations always yielded rickettsial DNA, indicating maintenance of rickettsial infection in the ticks by transstadial and transovarial passages. DNA sequences of random PCR products from eggs, larvae, nymphs, and adults were identified as R. amblyommii. All infested rabbits seroconverted to R. amblyommii antigens at the 21(st) day after infestation, indicating that larvae, nymphs, and adults transmitted R. amblyommii through parasitism. However, no infested rabbit presented fever or any clinical alteration during the experimental period. Rickettsiae were successfully isolated from the two A. auricularium females, and the isolates were established in Vero cell culture. Molecular characterization of the isolates confirmed R. amblyommii by sequencing partial gltA, ompA, and ompB genes. From another sample of 15 A. auricularium adult ticks collected from two armadillos (Euphractus sexcinctus), eight (53.3%) were infected by R. amblyommii. This study reports R. amblyommii infecting the tick A. auricularium for the first time. This is also the first report of rickettsia infecting ticks in the northeastern region of Brazil.

  2. Surface proteome analysis and characterization of surface cell antigen (Sca or autotransporter family of Rickettsia typhi.

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    Khandra T Sears

    Full Text Available Surface proteins of the obligate intracellular bacterium Rickettsia typhi, the agent of murine or endemic typhus fever, comprise an important interface for host-pathogen interactions including adherence, invasion and survival in the host cytoplasm. In this report, we present analyses of the surface exposed proteins of R. typhi based on a suite of predictive algorithms complemented by experimental surface-labeling with thiol-cleavable sulfo-NHS-SS-biotin and identification of labeled peptides by LC MS/MS. Further, we focus on proteins belonging to the surface cell antigen (Sca autotransporter (AT family which are known to be involved in rickettsial infection of mammalian cells. Each species of Rickettsia has a different complement of sca genes in various states; R. typhi, has genes sca1 thru sca5. In silico analyses indicate divergence of the Sca paralogs across the four Rickettsia groups and concur with previous evidence of positive selection. Transcripts for each sca were detected during infection of L929 cells and four of the five Sca proteins were detected in the surface proteome analysis. We observed that each R. typhi Sca protein is expressed during in vitro infections and selected Sca proteins were expressed during in vivo infections. Using biotin-affinity pull down assays, negative staining electron microscopy, and flow cytometry, we demonstrate that the Sca proteins in R. typhi are localized to the surface of the bacteria. All Scas were detected during infection of L929 cells by immunogold electron microscopy. Immunofluorescence assays demonstrate that Scas 1-3 and 5 are expressed in the spleens of infected Sprague-Dawley rats and Scas 3, 4 and 5 are expressed in cat fleas (Ctenocephalides felis. Sca proteins may be crucial in the recognition and invasion of different host cell types. In short, continuous expression of all Scas may ensure that rickettsiae are primed i to infect mammalian cells should the flea bite a host, ii to remain

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

    Science.gov (United States)

    Hudman, D A; Sargentini, N J

    2016-07-01

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

  4. Molecular detection of Rickettsia bellii in Amblyomma rotundatum from imported red-footed tortoise (Chelonoides carbonaria).

    Science.gov (United States)

    Erster, Oran; Roth, Asael; Avni, Zvi; King, Rony; Shkap, Varda

    2015-06-01

    Introduction of exotic ticks and pathogens through international animal trade (farm animals and pets) is a serious threat to public health and local fauna. Rapid and correct identification of potential threats is an important step on the way to conduct an efficient control of imported pests. In this report we describe the molecular identification of the neotropic tick Amblyomma rotundatum intercepted from red-footed tortoise (Chelonoides carbonaria), imported to Israel from Florida, USA. Molecular analysis of the ticks conducted upon their identification, revealed that they were infected with Rickettsia bellii. Following their collection, the ticks were examined morphologically and five molecular markers were used to determine their taxonomic identity: cytochrome c oxidase subunit 1 (COX1), cytochrome b (CytB), 12S rRNA, 16S rRNA and internal transcribed sequence 2 (ITS-2). Molecular analysis indicated that all of the collected ticks were Amblyomma rotundatum. Using rickettsial gltA (citrate synthase) gene in real-time PCR analysis we found that approximately 25% of the intercepted ticks (8 of 33) were infected with Rickettsia bellii. It is concluded that accurate and timely identification of imported exotic ticks prevented their introduction to Israel, and that use of molecular tools may further improve the response to such potential threats. Copyright © 2015 Elsevier GmbH. All rights reserved.

  5. Human prevalence of the spotted fever group (SFG) rickettsiae in endemic zones of Northwestern Colombia.

    Science.gov (United States)

    Londoño, Andrés F; Acevedo-Gutiérrez, Leidy Y; Marín, Diana; Contreras, Verónica; Díaz, Francisco J; Valbuena, Gustavo; Labruna, Marcelo B; Hidalgo, Marylin; Arboleda, Margarita; Mattar, Salim; Solari, Sergio; Rodas, Juan D

    2017-06-01

    In February 2006, an outbreak of human rickettsiosis occurred in the municipality of Necoclí Colombia, with 35% of lethality. This episode was, followed by two more, one in the municipality of Los Cordobas in 2007 with a 54% of lethality and the other one in the municipality of Turbo in 2008 with 27% of lethality. The aim of this study was to perform serological tests in healthy persons to determine the seroprevalence of antibodies against spotted fever group (SFG) rickettsiae and develop a survey to study some infection risk-related factors. A cross-sectional study was performed in 2011 and 2012. A blood sample and survey of associated factors was performed in healthy persons. A prevalence of 32%-41% was found in healthy people. From the multivariate analysis, we found that people living more than 16 years in these sites had a 79% higher risk of being seropositive and a 46% higher risk when they reported having birds in their houses if the variable of having a horse was included in the model. In conclusion, this study shows endemicity of at least one spotted fever group Rickettsia in the study zone. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Bartonella and Rickettsia in arthropods from the Lao PDR and from Borneo, Malaysia☆

    Science.gov (United States)

    Kernif, Tahar; Socolovschi, Cristina; Wells, Konstans; Lakim, Maklarin B.; Inthalad, Saythong; Slesak, Günther; Boudebouch, Najma; Beaucournu, Jean-Claude; Newton, Paul N.; Raoult, Didier; Parola, Philippe

    2012-01-01

    Rickettsioses and bartonelloses are arthropod-borne diseases of mammals with widespread geographical distributions. Yet their occurrence in specific regions, their association with different vectors and hosts and the infection rate of arthropod-vectors with these agents remain poorly studied in South-east Asia. We conducted entomological field surveys in the Lao PDR (Laos) and Borneo, Malaysia by surveying fleas, ticks, and lice from domestic dogs and collected additional samples from domestic cows and pigs in Laos. Rickettsia felis was detected by real-time PCR with similar overall flea infection rate in Laos (76.6%, 69/90) and Borneo (74.4%, 268/360). Both of the encountered flea vectors Ctenocephalides orientis and Ctenocephalides felis felis were infected with R. felis. The degrees of similarity of partial gltA and ompA genes with recognized species indicate the rickettsia detected in two Boophilus spp. ticks collected from a cow in Laos may be a new species. Isolation and further characterization will be necessary to specify it as a new species. Bartonella clarridgeiae was detected in 3/90 (3.3%) and 2/360 (0.6%) of examined fleas from Laos and Borneo, respectively. Two fleas collected in Laos and one flea collected in Borneo were co-infected with both R. felis and B. clarridgeiae. Further investigations are needed in order to isolate these agents and to determine their epidemiology and aetiological role in unknown fever in patients from these areas. PMID:22153360

  7. Investigation of Ehrlichia spp., Anaplasma spp. and Rickettsia spp. in ectoparasites collected from domestic animals, Rio de Janeiro State, Brazil

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    Thayssa Keren da Silva

    2017-09-01

    Full Text Available The aim of this study was to determine the occurrence of emerging arthropod-borne pathogens Anaplasma, Ehrlichia and Rickettsia infection in ticks (Acari: Ixodidae and fleas (Insecta: Siphonaptera collected from dogs and horses within municipality of Itaboraí, Rio de Janeiro State, Southern Brazil. Samples from 280 ticks and two fleas were subjected to family or/and genus specific PCR for Anaplasmataceae, Ehrlichia and Rickettsia, followed by DNA sequencing to ensure pathogen identity. In ticks Rhipicephalus sanguineus collected from dogs the DNA of Anaplasma platys and Ehrlichia canis was detected in 6.8% and 2.2% samples respectively. In two R. sanguineus confection with two pathogens was observed. In Dermacentor nitens ticks, collected from horses Francisella-like endosymbiont was found in 42.8% samples. DNA of Rickettsia felis and Wolbachia pi-petens was detected in fleas Ctenocephalides canis fleas. No DNA of Rickettsia was found in tested ticks. The findings contribute to our knowledge of tick-borne bacteria, ticks and endosymbionts distribution in Brazil.

  8. Tick-borne zoonotic pathogens in ticks feeding on the common nightingale including a novel strain of Rickettsia sp

    Czech Academy of Sciences Publication Activity Database

    Dubská, L.; Literák, I.; Kverek, P.; Roubalová, Eva; Kocianova, E.; Taragelova, V.

    2012-01-01

    Roč. 3, č. 4 (2012), s. 265-268 ISSN 1877-959X Institutional support: RVO:60077344 Keywords : tick * Ixodes ricinus * Borrelia garinii * Anaplasma phagocytophilum * Rickettsia helvetica * Babesia sp. EU1 * Common nightingale Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.353, year: 2012 http://www.sciencedirect.com/science/article/pii/S1877959X12000556

  9. Silencing urease: A key evolutionary step that facilitated the adaptation of Yersinia pestis to the flea-borne transmission route

    Science.gov (United States)

    Chouikha, Iman; Hinnebusch, B. Joseph

    2014-01-01

    The arthropod-borne transmission route of Yersinia pestis, the bacterial agent of plague, is a recent evolutionary adaptation. Yersinia pseudotuberculosis, the closely related food-and water-borne enteric species from which Y. pestis diverged less than 6,400 y ago, exhibits significant oral toxicity to the flea vectors of plague, whereas Y. pestis does not. In this study, we identify the Yersinia urease enzyme as the responsible oral toxin. All Y. pestis strains, including those phylogenetically closest to the Y. pseudotuberculosis progenitor, contain a mutated ureD allele that eliminated urease activity. Restoration of a functional ureD was sufficient to make Y. pestis orally toxic to fleas. Conversely, deletion of the urease operon in Y. pseudotuberculosis rendered it nontoxic. Enzymatic activity was required for toxicity. Because urease-related mortality eliminates 30–40% of infective flea vectors, ureD mutation early in the evolution of Y. pestis was likely subject to strong positive selection because it significantly increased transmission potential. PMID:25453069

  10. Estimated seroprevalence of Anaplasma spp. and spotted fever group Rickettsia exposure among herders and livestock in Mongolia.

    Science.gov (United States)

    von Fricken, Michael E; Lkhagvatseren, Sukhbaatar; Boldbaatar, Bazartseren; Nymadawa, Pagbajab; Weppelmann, Thomas A; Baigalmaa, Bekh-Ochir; Anderson, Benjamin D; Reller, Megan E; Lantos, Paul M; Gray, Gregory C

    2018-01-01

    To better understand the epidemiology of tick-borne disease in Mongolia, a comprehensive seroprevalence study was conducted investigating exposure to Anaplasma spp. and spotted fever group (SFG) Rickettsia spp. in nomadic herders and their livestock across three provinces from 2014 to 2015. Blood was collected from 397 herders and 2370 livestock, including sheep, goats, cattle, horses and camels. Antibodies against Anaplasma spp. and SFG Rickettsia were determined by indirect immunofluorescence using commercially available slides coated with Anaplasma phagocytophilum and Rickettsia rickettsii antigens. Logistic regression was used to determine if the odds of previous exposure differed by gender, location, and species, with or without adjustment for age. To examine the association between seroprevalence and environmental variables we used ArcGIS to circumscribe the five major clusters where human and animal data were collected. Anaplasma spp. exposure was detected in 37.3% (136/365) of humans and 47.3% (1120/2370) of livestock; SFG Rickettsia exposure was detected in 19.5% (73/374) humans and 20.4% (478/2342) livestock. Compared to the southern province (aimag) of Dornogovi, located in the Gobi Desert, humans were significantly more likely to be exposed to Anaplasma spp. and SFG Rickettsia in the northern provinces of Tov (OR=7.3, 95% CI: 3.5, 15.1; OR=3.3, 95% CI: 1.7, 7.5), and Selenge (OR=6.9, 95% CI: 3.4, 14.0; OR=2.2, 95% CI: 1.1, 4.8). The high seroprevalence of Anaplasma spp. and SFG Rickettsia in humans and livestock suggests that exposure to tick-borne pathogens may be common in herders and livestock in Mongolia, particularly in the more northern regions of the country. Until more is known about these pathogens in Mongolia, physicians and veterinarians in the countryside should consider testing for Anaplasma and SFG Rickettsia infections and treating clinically compatible cases, while public health authorities should expand surveillance efforts for these

  11. Multi-omics Analysis Sheds Light on the Evolution and the Intracellular Lifestyle Strategies of Spotted Fever Group Rickettsia spp.

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    Khalid El Karkouri

    2017-07-01

    Full Text Available Arthropod-borne Rickettsia species are obligate intracellular bacteria which are pathogenic for humans. Within this genus, Rickettsia slovaca and Rickettsia conorii cause frequent and potentially severe infections, whereas Rickettsia raoultii and Rickettsia massiliae cause rare and milder infections. All four species belong to spotted fever group (SFG rickettsiae. However, R. slovaca and R. raoultii cause scalp eschar and neck lymphadenopathy (SENLAT and are mainly associated with Dermacentor ticks, whereas the other two species cause Mediterranean spotted fever (MSF and are mainly transmitted by Rhipicephalus ticks. To identify the potential genes and protein profiles and to understand the evolutionary processes that could, comprehensively, relate to the differences in virulence and pathogenicity observed between these four species, we compared their genomes and proteomes. The virulent and milder agents displayed divergent phylogenomic evolution in two major clades, whereas either SENLAT or MSF disease suggests a discrete convergent evolution of one virulent and one milder agent, despite their distant genetic relatedness. Moreover, the two virulent species underwent strong reductive genomic evolution and protein structural variations, as well as a probable loss of plasmid(s, compared to the two milder species. However, an abundance of mobilome genes was observed only in the less pathogenic species. After infecting Xenopus laevis cells, the virulent agents displayed less up-regulated than down-regulated proteins, as well as less number of identified core proteins. Furthermore, their similar and distinct protein profiles did not contain some genes (e.g., ompA/B and rickA known to be related to rickettsial adhesion, motility and/or virulence, but may include other putative virulence-, antivirulence-, and/or disease-related proteins. The identified evolutionary forces herein may have a strong impact on intracellular expressions and strategies in

  12. Molecular detection of Rickettsia typhi in cats and fleas.

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    Maria Mercedes Nogueras

    Full Text Available BACKGROUND: Rickettsiatyphi is the etiological agent of murine typhus (MT, a disease transmitted by two cycles: rat-flea-rat, and peridomestic cycle. Murine typhus is often misdiagnosed and underreported. A correct diagnosis is important because MT can cause severe illness and death. Our previous seroprevalence results pointed to presence of human R. typhi infection in our region; however, no clinical case has been reported. Although cats have been related to MT, no naturally infected cat has been described. The aim of the study is to confirm the existence of R. typhi in our location analyzing its presence in cats and fleas. METHODOLOGY/PRINCIPAL FINDINGS: 221 cats and 80 fleas were collected from Veterinary clinics, shelters, and the street (2001-2009. Variables surveyed were: date of collection, age, sex, municipality, living place, outdoor activities, demographic area, healthy status, contact with animals, and ectoparasite infestation. IgG against R. typhi were evaluated by indirect immunofluorescence assay. Molecular detection in cats and fleas was performed by real-time PCR. Cultures were performed in those cats with positive molecular detection. Statistical analysis was carried out using SPSS. A p < 0.05 was considered significant. Thirty-five (15.8% cats were seropositive. There were no significant associations among seropositivity and any variables. R. typhi was detected in 5 blood and 2 cultures. High titres and molecular detection were observed in stray cats and pets, as well as in spring and winter. All fleas were Ctenocephalides felis. R. typhi was detected in 44 fleas (55%, from shelters and pets. Co-infection with R. felis was observed. CONCLUSIONS: Although no clinical case has been described in this area, the presence of R. typhi in cats and fleas is demonstrated. Moreover, a considerable percentage of those animals lived in households. To our knowledge, this is the first time R. typhi is detected in naturally infected cats.

  13. RC1339/APRc from Rickettsia conorii is a novel aspartic protease with properties of retropepsin-like enzymes.

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    Rui Cruz

    2014-08-01

    Full Text Available Members of the species Rickettsia are obligate intracellular, gram-negative, arthropod-borne pathogens of humans and other mammals. The life-threatening character of diseases caused by many Rickettsia species and the lack of reliable protective vaccine against rickettsioses strengthens the importance of identifying new protein factors for the potential development of innovative therapeutic tools. Herein, we report the identification and characterization of a novel membrane-embedded retropepsin-like homologue, highly conserved in 55 Rickettsia genomes. Using R. conorii gene homologue RC1339 as our working model, we demonstrate that, despite the low overall sequence similarity to retropepsins, the gene product of rc1339 APRc (for Aspartic Protease from Rickettsia conorii is an active enzyme with features highly reminiscent of this family of aspartic proteases, such as autolytic activity impaired by mutation of the catalytic aspartate, accumulation in the dimeric form, optimal activity at pH 6, and inhibition by specific HIV-1 protease inhibitors. Moreover, specificity preferences determined by a high-throughput profiling approach confirmed common preferences between this novel rickettsial enzyme and other aspartic proteases, both retropepsins and pepsin-like. This is the first report on a retropepsin-like protease in gram-negative intracellular bacteria such as Rickettsia, contributing to the analysis of the evolutionary relationships between the two types of aspartic proteases. Additionally, we have also shown that APRc is transcribed and translated in R. conorii and R. rickettsii and is integrated into the outer membrane of both species. Finally, we demonstrated that APRc is sufficient to catalyze the in vitro processing of two conserved high molecular weight autotransporter adhesin/invasion proteins, Sca5/OmpB and Sca0/OmpA, thereby suggesting the participation of this enzyme in a relevant proteolytic pathway in rickettsial life-cycle. As a

  14. Candidatus Rickettsia andeanae, a spotted fever group agent infecting Amblyomma parvum ticks in two Brazilian biomes

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    Fernanda Aparecida Nieri-Bastos

    2014-04-01

    Full Text Available Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul and from horses in the Cerrado biome (state of Piauí in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63 and 66.7% (2/3 of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB genes of Candidatus Rickettsia andeanae. This report is the first to describe Ca. R. andeanae in Brazil.

  15. Candidatus Rickettsia andeanae, a spotted fever group agent infecting Amblyomma parvum ticks in two Brazilian biomes.

    Science.gov (United States)

    Nieri-Bastos, Fernanda Aparecida; Lopes, Marcos Gomes; Cançado, Paulo Henrique Duarte; Rossa, Giselle Ayres Razera; Faccini, João Luiz Horácio; Gennari, Solange Maria; Labruna, Marcelo Bahia

    2014-04-01

    Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the Cerrado biome (state of Piauí) in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR) targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB genes of Candidatus Rickettsia andeanae. This report is the first to describe Ca. R. andeanae in Brazil.

  16. Rickettsia felis in Ctenocephalides felis felis from Five Geographic Regions of Brazil

    Science.gov (United States)

    Horta, Mauricio C.; Ogrzewalska, Maria; Azevedo, Milka C.; Costa, Francisco B.; Ferreira, Fernando; Labruna, Marcelo B.

    2014-01-01

    This study evaluated rickettsial infection in 701 Ctenocephalides felis felis fleas that were collected from dogs and cats in 31 municipalities, encompassing all regions and major biomes of Brazil. A total of 268 (38.2%) fleas from 30 municipalities were polymerase chain reaction (PCR) positive for the rickettsial gltA gene. The PCR products from 44 fleas, consisting of at least 1 PCR-positive flea from each of 30 municipalities, generated DNA sequences identical to Rickettsia felis. Rickettsial prevalence was highly variable among 30 municipalities, with values ranging from 2.9% to 100%. Significantly higher infection rates by R. felis were associated with the Pampa biome (southern Brazil), and the temperate climate that prevails in southern Brazil. In contrast, lowest R. felis-infection rates were significantly associated with the Caatinga biome, and its semiarid climate. Further studies should evaluate the effect of temperature and moisture on the R. felis infection in Ctenocephalides fleas world widely. PMID:24778194

  17. Feeding period required by Amblyomma aureolatum ticks for transmission of Rickettsia rickettsii to vertebrate hosts.

    Science.gov (United States)

    Saraiva, Danilo G; Soares, Herbert S; Soares, João Fábio; Labruna, Marcelo B

    2014-09-01

    Rocky Mountain spotted fever is endemic to the São Paulo metropolitan area, Brazil, where the etiologic agent, Rickettsia rickettsii, is transmitted to humans by adult Amblyomma aureolatum ticks. We determined the minimal feeding period required by A. aureolatum nymphs and adults to transmit R. rickettsii to guinea pigs. Unfed nymphs and unfed adult ticks had to be attached to the host for >10 hours to transmit R. rickettsii. In contrast, fed ticks needed a minimum of 10 minutes of attachment to transmit R. rickettsii to hosts. Most confirmed infections of Rocky Mountain spotted fever in humans in the São Paulo metropolitan area have been associated with contact with domestic dogs, the main host of A. aureolatum adult ticks. The typical expectation that transmission of tickborne bacteria to humans as well as to dogs requires ≥2 hours of tick attachment may discourage persons from immediately removing them and result in transmission of this lethal bacterium.

  18. 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

    Borreliosis is an endemic infection in Denmark. Recent serosurveys have indicated that human anaplasmosis may be equally common. The aim of this study was to look for Anaplasma phagocytophilum and related pathogens in Ixodes ricinus ticks and estimate their prevalence, compared to Borrelia, using...... Jutland and Funen, while 11% were positive for Borrelia burgdorferi. The Borrelia genotype B. afzelii was most prevalent, followed by B. valaisiana, B. burgdorferi s.s. and B. garinii.A. phagocytophilum was found in 14.5% of nymphs and 40.5% of adult ticks, while Borrelia was found in 13% of nymphs and 8......% 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...

  19. Novel Rickettsia raoultii strain isolated and propagated from Austrian Dermacentor reticulatus ticks

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    Michiel Wijnveld

    2016-11-01

    Full Text Available Abstract Background Continuous culture of tick cell lines has proven a valuable asset in isolating and propagating several different vector-borne pathogens, making it possible to study these microorganisms under laboratory conditions and develop serological tests to benefit public health. We describe a method for effective, cost- and labor-efficient isolation and propagation of Rickettsia raoultii using generally available laboratory equipment and Rhipicephalus microplus cells, further demonstrating the usefulness of continuous tick cell lines. R. raoultii is one of the causative agents of tick-borne lymphadenopathy (TIBOLA and is, together with its vector Dermacentor reticulatus, emerging in novel regions of Europe, giving rise to an increased threat to general public health. Methods Dermacentor reticulatus ticks were collected in the Donau-Auen (Lobau national park in Vienna, Austria. The hemolymph of ten collected ticks was screened by PCR-reverse line blot for the presence of rickettsial DNA. A single tick tested positive for R. raoultii DNA and was used to infect Rhipicephalus microplus BME/CTVM2 cells. Results Sixty-five days after infection of the tick-cell line with an extract from a R. raoultii-infected tick, we observed intracellular bacteria in the cultured cells. On the basis of microscopy we suspected that the intracellular bacteria were a species of Rickettsia; this was confirmed by several PCRs targeting different genes. Subsequent sequencing showed 99–100 % identity with R. raoultii. Cryopreservation and resuscitation of R. raoultii was successful. After 28 days identical intracellular bacteria were microscopically observed. Conclusions R. raoultii was successfully isolated and propagated from D. reticulatus ticks using R. microplus BME/CTVM2 cells. The isolated strain shows significant molecular variation compared to currently known sequences. Furthermore we show for the first time the successful cryopreservation and

  20. Identification of novel surface-exposed proteins of Rickettsia rickettsii by affinity purification and proteomics.

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    Wenping Gong

    Full Text Available Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, is the most pathogenic member among Rickettsia spp. Surface-exposed proteins (SEPs of R. rickettsii may play important roles in its pathogenesis or immunity. In this study, R. rickettsii organisms were surface-labeled with sulfo-NHS-SS-biotin and the labeled proteins were affinity-purified with streptavidin. The isolated proteins were separated by two-dimensional electrophoresis, and 10 proteins were identified among 23 protein spots by electrospray ionization tandem mass spectrometry. Five (OmpA, OmpB, GroEL, GroES, and a DNA-binding protein of the 10 proteins were previously characterized as surface proteins of R. rickettsii. Another 5 proteins (Adr1, Adr2, OmpW, Porin_4, and TolC were first recognized as SEPs of R. rickettsii herein. The genes encoding the 5 novel SEPs were expressed in Escherichia coli cells, resulting in 5 recombinant SEPs (rSEPs, which were used to immunize mice. After challenge with viable R. rickettsii cells, the rickettsial load in the spleen, liver, or lung of mice immunized with rAdr2 and in the lungs of mice immunized with other rSEPs excluding rTolC was significantly lower than in mice that were mock-immunized with PBS. The in vitro neutralization test revealed that sera from mice immunized with rAdr1, rAdr2, or rOmpW reduced R. rickettsii adherence to and invasion of vascular endothelial cells. The immuno-electron microscopic assay clearly showed that the novel SEPs were located in the outer and/or inner membrane of R. rickettsii. Altogether, the 5 novel SEPs identified herein might be involved in the interaction of R. rickettsii with vascular endothelial cells, and all of them except TolC were protective antigens.

  1. Identification of Rickettsia africae and Wolbachia sp. in Ceratophyllus garei fleas from Passerine birds migrated from Africa.

    Science.gov (United States)

    Sekeyová, Zuzana; Mediannikov, Oleg; Roux, Véronique; Subramanian, Geetha; Spitalská, Eva; Kristofík, Jano; Darolová, Alžbeta; Raoult, Didier

    2012-07-01

    The aim of the study was to reveal new aspects of the role of flea vector taken from migratory birds by screening of specimens with molecular biological methods. A field study was done in fishponds in Slovakia. Actually, 47 fleas were collected from reed warblers (Acrocephalus scirpaceus) and their nests. DNA was extracted and analyzed for representatives of the orders Rickettsiales. A rickettsia that shares 99.7% of identity by gltA gene with Rickettsia africae was identified in Ceratophyllus garei collected from A. scirpaceus. Moreover, two Wolbachia sp. were also detected in fleas. This is the first record of R. africae and Wolbachia sp. identified so far in Central Europe in fleas collected from migratory bird returning from Africa. This molecular study extends the geographic range and vector spectrum of arthropod-borne agents.

  2. Liolaemus lizards (Squamata: Liolaemidae) as hosts for the nymph of Amblyomma parvitarsum (Acari: Ixodidae), with notes on Rickettsia infection.

    Science.gov (United States)

    Muñoz-Leal, Sebastián; Tarragona, Evelina L; Martins, Thiago F; Martín, Claudia M; Burgos-Gallardo, Freddy; Nava, Santiago; Labruna, Marcelo B; González-Acuña, Daniel

    2016-10-01

    Adults of Amblyomma parvitarsum are common ectoparasites of South American camelids of the genera Lama and Vicugna, occuring in highlands of Argentina, Bolivia, Chile, Peru and also in Argentinean Patagonia. Whereas larval stages of this tick are known to feed on small lizards, host records for the nymphal instar have remained unreported. Supported by morphological and molecular analyses, herein we report A. parvitarsum nymphs parasitizing two Liolaemus species (Reptilia: Squamata) in the Andean Plateau of Argentina and Chile. Additionally, by a PCR screening targetting gltA and ompA genes, DNA of Rickettsia was detected in one of the collected nymphs. Obtained sequences of this agent were identical to a recent Rickettsia sp. described infecting adults of this tick species in Chile and Argentina.

  3. Molecular detection of hemoprotozoa and Rickettsia species in arthropods collected from wild animals in the Burgos Province, Spain

    OpenAIRE

    Lledó, Lourdes; Giménez-Pardo, Consuelo; Domínguez-Peñafiel, Gerardo; Sousa, Rita; Gegúndez, Maria Isabep; Casado, Nieves; Criado, Angel

    2010-01-01

    Limited information on the presence of bacterial and hematozoan infections in parasitic arthropods from Spain is available. In an attempt to address this issue, the prevalence of Theileria, Babesia, Hepatozoon, and Rickettsia species was investigated by polymerase chain reaction plus sequencing. In a survey for zoonotic pathogens in ectoparasites, 42 wild animals (which included rodents, carnivores, Sciuridae, and Cervidae) were captured in Burgos (Spain). A total of 256 arthropods (including...

  4. Rickettsia rickettsii infecting Rhipicephalus sanguineus sensu lato (Latreille 1806), in high altitude atlantic forest fragments, Ceara State, Brazil.

    Science.gov (United States)

    Silva, Arannadia Barbosa; Duarte, Myrian Morato; da Costa Cavalcante, Robson; de Oliveira, Stefan Vilges; Vizzoni, Vinicius Figueiredo; de Lima Duré, Ana Íris; de Melo Iani, Felipe Campos; Machado-Ferreira, Erik; Gazêta, Gilberto Salles

    2017-09-01

    In Brazil, Spotted Fever (SF) is caused by Rickettsia rickettsii and Rickettsia parkeri strain Atlantic Forest. In recent years, several human cases of a milder SF have been reported from the Maciço de Baturité region of Ceará State. Previous studies in this region found R. parkeri strain Atlantic Forest to be present in Rhipicephalus sanguineus sensu lato and Amblyomma ovale ticks. The present study isolated and identified the Rickettsia spp. present in this new endemic area in Brazil. In March 2015, R. sanguineus s.l. and A. ovale were collected in rural areas of the Maciço de Baturité region, and subjected to the isolation technique. A bacterium was isolated from one R. sanguineus s.l., which phylogenetic analysis clustered to the R. rickettsii group. In conclusion, R. rickettsii bacteria is circulating in the studied area and may in future have an impact on the clinical diagnoses and consequently cause changes in the profile of the disease in the region. In addition, we suggest the increase of epidemiological and environmental surveillance in the area, in order to prevent Brazilian Spotted Fever cases. Copyright © 2017. Published by Elsevier B.V.

  5. High detection rate of Rickettsia africae in Amblyomma variegatum but low prevalence of anti-rickettsial antibodies in healthy pregnant women in Madagascar.

    Science.gov (United States)

    Keller, Christian; Krüger, Andreas; Schwarz, Norbert Georg; Rakotozandrindrainy, Raphael; Rakotondrainiarivelo, Jean Philibert; Razafindrabe, Tsiry; Derschum, Henri; Silaghi, Cornelia; Pothmann, Daniela; Veit, Alexandra; Hogan, Benedikt; May, Jürgen; Girmann, Mirko; Kramme, Stefanie; Fleischer, Bernhard; Poppert, Sven

    2016-02-01

    Tick-borne spotted fever group (SFG) rickettsioses are emerging infectious diseases in Sub-Saharan Africa. In Madagascar, the endemicity of tick-borne rickettsiae and their vectors has been incompletely studied. The first part of the present study was conducted in 2011 and 2012 to identify potential anthropophilic tick vectors for SFG rickettsiae on cattle from seven Malagasy regions, and to detect and characterize rickettsiae in these ticks. Amblyomma variegatum was the only anthropophilic tick species found on 262 cattle. Using a novel ompB-specific qPCR, screening for rickettsial DNA was performed on 111 A. variegatum ticks. Rickettsial DNA was detected in 96 of 111 ticks studied (86.5%). Rickettsia africae was identified as the only infecting rickettsia using phylogenetic analysis of ompA and ompB gene sequences and three variable intergenic spacers from 11 ticks. The second part of the study was a cross-sectional survey for antibodies against SFG rickettsiae in plasma samples taken from healthy, pregnant women at six locations in Madagascar, two at sea level and four between 450 and 1300m altitude. An indirect fluorescent antibody test with Rickettsia conorii as surrogate SFG rickettsial antigen was used. We found R. conorii-seropositives at all altitudes with prevalences between 0.5% and 3.1%. Our results suggest that A. variegatum ticks highly infected with R. africae are the most prevalent cattle-associated tick vectors for SFG rickettsiosis in Madagascar. Transmission of SFG rickettsiosis to humans occurs at different altitudes in Madagascar and should be considered as a relevant cause of febrile diseases. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. Isolamento de Rickettsia em cultura de células vero

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    Melles Heloisa Helena Barbosa

    1999-01-01

    Full Text Available Embora o diagnóstico da febre maculosa baseie-se em sinais e sintomas característicos, o mesmo requer confirmação laboratorial, pois existem alguns diagnósticos diferenciais possíveis como meningococcemia, leptospirose, infecção por enterovírus e febre tifóide. A confirmação laboratorial pode ser feita através da pesquisa de anticorpos específicos, possível somente alguns dias após o aparecimento da doença, através do isolamento do agente em amostras de sangue e/ou biópsia de pele, e ainda, de amostras de carrapatos coletados do paciente ou de animais reservatório. O isolamento a partir de sangue ou biópsia de pele resulta em diagnóstico precoce da doença, pois na fase de rickettsemia ainda não há anticorpos detectáveis no sangue. Assim, com o objetivo de facilitar o diagnóstico precoce da febre maculosa, estabelecemos um método de isolamento de rickettsia em cultura de células vero. Para a padronização foi inoculada amostra padrão de Rickettsia rickettsii, cepa Sheyla Smith, cedida pelo CDC. A identificação foi feita através da reação de imunofluorescência indireta. A presença de microrganismos verdes fluorescentes visualizados no interior do citoplasma das células caracterizou o crescimento do agente. Posteriormente, a metodologia foi confirmada pelo isolamento do agente da febre maculosa em amostras de biópsia de pele de paciente proveniente de área endêmica no Estado de São Paulo, bem como, de amostras de carrapato do gênero Amblyomma, considerado o reservatório e transmissor da doença no Brasil.

  7. Prevalence of Rickettsia spp. in Ticks and Serological and Clinical Outcomes in Tick-Bitten Individuals in Sweden and on the Åland Islands.

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    Anders Lindblom

    Full Text Available Tick-transmitted diseases are an emerging health problem, and the hard tick Ixodes ricinus is the main vector for Borrelia spp., tick-borne encephalitis virus and most of the spotted fever Rickettsiae in Europe. The aim of the present study was to examine the incidence of rickettsial infection in the southernmost and south central parts of Sweden and the Åland Islands in Finland, the risk of infection in humans and its correlation with a bite of a Rickettsia-infected tick, the self-reported symptoms of rickettsial disease, and the prevalence of co-infection between Rickettsia spp. and Borrelia spp. Persons with a recent tick bite were enrolled through public media and asked to answer a questionnaire, provide a blood sample and bring detached ticks at enlistment and at follow-up three months later. Blood samples were previously analysed for Borrelia spp. antibodies and, for this report, analysed for antibodies to Rickettsia spp. by immunofluorescence and in 16 cases also using Western Blot. Ninety-six (44.0% of the 218 participants were seropositive for IgG antibodies to Rickettsia spp. Forty (18.3% of the seropositive participants had increased titres at the follow-up, indicating recent/current infection, while four (1.8% had titres indicating probable recent/current infection (≥1:256. Of 472 ticks, 39 (8.3% were Rickettsia sp. positive. Five (31.3% of 16 participants bitten by a Rickettsia-infected tick seroconverted. Experience of the self-reported symptoms nausea (p = 0.006 and radiating pain (p = 0.041 was more common among those with recent, current or probable infection compared to those who did not seroconvert. Participants who showed seroreactivity or seroconversion to Rickettsia spp. had more symptoms than those who were seronegative. Seven (3.2% participants showed seroconversion to Borrelia spp., and three (1.4% of these showed seroconversion to both Rickettsia spp. and Borrelia spp., in accordance with previous studies in Sweden

  8. Prevalence of Rickettsia spp. in Ticks and Serological and Clinical Outcomes in Tick-Bitten Individuals in Sweden and on the Åland Islands.

    Science.gov (United States)

    Lindblom, Anders; Wallménius, Katarina; Sjöwall, Johanna; Fryland, Linda; Wilhelmsson, Peter; Lindgren, Per-Eric; Forsberg, Pia; Nilsson, Kenneth

    2016-01-01

    Tick-transmitted diseases are an emerging health problem, and the hard tick Ixodes ricinus is the main vector for Borrelia spp., tick-borne encephalitis virus and most of the spotted fever Rickettsiae in Europe. The aim of the present study was to examine the incidence of rickettsial infection in the southernmost and south central parts of Sweden and the Åland Islands in Finland, the risk of infection in humans and its correlation with a bite of a Rickettsia-infected tick, the self-reported symptoms of rickettsial disease, and the prevalence of co-infection between Rickettsia spp. and Borrelia spp. Persons with a recent tick bite were enrolled through public media and asked to answer a questionnaire, provide a blood sample and bring detached ticks at enlistment and at follow-up three months later. Blood samples were previously analysed for Borrelia spp. antibodies and, for this report, analysed for antibodies to Rickettsia spp. by immunofluorescence and in 16 cases also using Western Blot. Ninety-six (44.0%) of the 218 participants were seropositive for IgG antibodies to Rickettsia spp. Forty (18.3%) of the seropositive participants had increased titres at the follow-up, indicating recent/current infection, while four (1.8%) had titres indicating probable recent/current infection (≥1:256). Of 472 ticks, 39 (8.3%) were Rickettsia sp. positive. Five (31.3%) of 16 participants bitten by a Rickettsia-infected tick seroconverted. Experience of the self-reported symptoms nausea (p = 0.006) and radiating pain (p = 0.041) was more common among those with recent, current or probable infection compared to those who did not seroconvert. Participants who showed seroreactivity or seroconversion to Rickettsia spp. had more symptoms than those who were seronegative. Seven (3.2%) participants showed seroconversion to Borrelia spp., and three (1.4%) of these showed seroconversion to both Rickettsia spp. and Borrelia spp., in accordance with previous studies in Sweden. Symptoms

  9. [Detection of Rickettsia in ectoparasites of wild and domestic mammals from the Cerro Chucanti private reserve and from neighboring towns, Panamá, 2007-2010].

    Science.gov (United States)

    Bermúdez, Sergio; Miranda, Roberto; Zaldívar, Yamitze; González, Publio; Berguido, Guido; Trejos, Diomedes; Pascale, Juan M; Labruna, Marcelo

    2012-06-01

    Ectoparasites are the main vectors of rickettsiosis. In Panama, however, limited data are available concerning the arthropod species that serve as vectors or reservoirs. Data are presented concerning the presence of Rickettsia in ectoparasites of wildlife and domestic animals in the Cerro Chucantí private nature reserve and in neighboring villages. Nine humans, 95 domestic mammals and 48 wild mammals were examined. Twenty-one species of ectoparasites were obtained, including fleas, lice, ticks and mites. These were preserved in 95% ethanol. Later, the DNA was extracted from the ticks and fleas and analyzed by molecular techniques to detect presence of Rickettsia. Of a total of 425 PCR reactions, 270 were positive for Rickettsia and 155 negative. Among the positive samples, 86 PCR amplified for the gltA gene (55% of positives) and 41 of these also amplified the ompA gene. DNA of Rickettsia amblyommii was found in horses ticks (Amblyomma cajennense, Dermacentor nitens), dogs ticks (Rhipicephalus sanguineus) and free living nymphs in the forest. Additionally, DNA of R. felis was found in fleas from dogs Ctenocephalides felis. The presence of R. amblyommii and R. felis was detected in ticks and fleas of domestic animals in villages near Cerro Chucanti; however no Rickettsia DNA was found in ectoparasites of non-domestic wildlife.

  10. Spotted Fever Group Rickettsia in Small Rodents from Areas of Low Endemicity for Brazilian Spotted Fever in the Eastern Region of Minas Gerais State, Brazil

    Science.gov (United States)

    Milagres, Bruno S.; Padilha, Amanda F.; Montandon, Carlos E.; Freitas, Renata N.; Pacheco, Richard; Walker, David H.; Labruna, Marcelo B.; Mafra, Cláudio L.; Galvão, Márcio A. M.

    2013-01-01

    We investigated the humoral immune response against different species of Rickettsia in serum samples from small rodents collected in two areas of a silent focus for Brazilian spotted fever in the eastern region of Minas Gerais State, Brazil. Sera samples were analyzed by indirect immunofluorescence assay using antigens from Rickettsia species of the spotted fever, ancestral, and transition groups. Titers ≥ 1:64 were considered positive. In Santa Cruz do Escalvado, 94% (30 of 32) of the samples collected from Rattus rattus, 22% (5 of 23) from Nectomys squamipes, and 80% (4 of 5) from Akodon sp., reacted by indirect immunofluorescence assay with Rickettsia antigens of the spotted fever group. In the municipality of Pingo D'Água, 84% (26 of 31) of the samples collected from R. rattus, 86% (6 of 7) of the samples from Oryzomys subflavus, 86% (6 of 7) from N. squamipes, and 100% (1 of 1) from Bolomys sp. contained antibodies that reacted with rickettsial antigens of the spotted fever group. These results demonstrated the previous exposure of small rodents to spotted fever group Rickettsia, suggesting the participation of these animals in the natural history of these rickettsiae in this region. PMID:23509125

  11. Distribution of Rickettsia rickettsii in ovary cells of Rhipicephalus sanguineus (Latreille1806 (Acari: Ixodidae

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    da Silva Costa Luís

    2011-11-01

    Full Text Available Abstract Background Considering the fact that the dog tick, Rhipicephalus sanguineus, has a great potential to become the vector of Brazilian Spotted Fever (BSF for humans, the present study aimed to describe the distribution of the bacterium Rickettsia rickettsii, the etiological agent of BSF, in different regions of the ovaries of R. sanguineus using histological techniques. The ovaries were obtained from positive females confirmed by the hemolymph test and fed in the nymph stage on guinea pigs inoculated with R. rickettsii. Results The results showed a general distribution of R. rickettsii in the ovary cells, being found in oocytes in all stages of development (I, II, III, IV and V most commonly in the periphery of the oocyte and also in the cytoplasm of pedicel cells. Conclusions The histological analysis of the ovaries of R. sanguineus infected females confirmed the presence of the bacterium, indicating that the infection can interfere negatively in the process of reproduction of the ticks, once alterations were detected both in the shape and cell structure of the oocytes which contained bacteria.

  12. Fiebre manchada por rickettsias en el Delta del Paraná: Una enfermedad emergente Rickettsial spotted fever in the Paraná Delta: An emerging disease

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    Alfredo Seijo

    2007-12-01

    Full Text Available Se comunica un caso de fiebre manchada por rickettsia autóctono del delta del Paraná correspondiente a la provincia de Buenos Aires. Luego de cinco días de haber permanecido en una región cercana a la localidad de ingeniero Otamendi, partido de Campana, el paciente presentó un síndrome febril agudo caracterizado por hipertermia con escalofríos y sudoración, mialgias, cefalea, astenia y discreta odinofagia, seguido a las 72 horas por un exantema maculopapuloso congestivo con elementos purpúricos, de distribución universal. En la región preauricular izquierda se observaba una lesión papuloerosiva, producida cinco días antes de iniciada la fiebre por una garrapata adquirida en el lugar. El cuadro clínico remitió rápidamente con la administración de doxiciclina. Por inmunofluorescencia indirecta se identificaron anticuerpos reactivos contra el grupo de rickettsias causantes de fiebres manchadas (CDC, Atlanta, EE.UU.. Se realizan consideraciones sobre la especie de rickettsia, el vector involucrado y la posibilidad que la enfermedad fuera debida a Rickettsia parkeri.We describe a case of rickettsial spotted fever in the Paraná Delta region of Buenos Aires province in Argentina. The patient developed an acute febrile syndrome characterized by myalgias, headache, asthenia and moderate odynophagia, followed by a diffuse macular, papular, and purpuric exanthema. The patient had been bitten recently by a tick on the left preauricular region and an erosive papular lesion was evident at the bite site. An indirect immunofluorescence antibody assay identified antibodies reactive with spotted fever group rickettsiae in the patient's serum. The patient improved rapidly with doxycycline. Several considerations relating to the identity of the rickettsial species and tick vector are discussed, including the possibility that this patient's illness may have been caused by Rickettsia parkeri.

  13. Transmission dynamics and control of Rickettsia rickettsii in populations of Hydrochoerus hydrochaeris and Amblyomma sculptum.

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    Gina Polo

    2017-06-01

    Full Text Available Brazilian Spotted Fever (BSF, caused by the bacterium Rickettsia rickettsii, is the tick-borne disease that generates the largest number of human deaths in the world. In Brazil, the current increase of BSF human cases has been associated with the presence and expansion of capybaras Hydrochoerus hydrochaeris, which act as primary hosts for the tick Amblyomma sculptum, vector of the R. rickettsii in this area.We proposed a semi-discrete-time stochastic model to evaluate the role of capybaras in the transmission dynamics of R. rickettsii. Through a sensitivity analysis, we identified the parameters with significant influence on the R. rickettsii establishment. Afterward, we implemented the Gillespie's algorithm to simulate the impact of potential public health interventions to prevent BSF human cases.The introduction of a single infected capybara with at least one infected attached tick is enough to trigger the disease in a non-endemic area. We found that to avoid the formation of new BSF-endemic areas, it is crucial to impede the emigration of capybaras from endemic areas by reducing their birth rate by more than 58%. Model results were corroborated by ex-situ data generated from field studies, and this supports our proposal to prevent BSF human cases by implementing control strategies focused on capybaras.The proposed stochastic model illustrates how strategies for the control and prevention of vector-borne infectious diseases can be focused on amplifier hosts management practices. This work provides a basis for future prevention strategies for other neglected vector-borne diseases.

  14. Investigation of tick-borne bacteria (Rickettsia spp., Anaplasma spp., Ehrlichia spp. and Borrelia spp.) in ticks collected from Andean tapirs, cattle and vegetation from a protected area in Ecuador.

    Science.gov (United States)

    Pesquera, Cristina; Portillo, Aránzazu; Palomar, Ana M; Oteo, José A

    2015-01-24

    Ixodid ticks play an important role in the transmission and ecology of infectious diseases. Information about the circulation of tick-borne bacteria in ticks is lacking in Ecuador. Our aims were to investigate the tick species that parasitize Andean tapirs and cattle, and those present in the vegetation from the buffer zone of the Antisana Ecological Reserve and Cayambe-Coca National Park (Ecuador), and to investigate the presence of tick-borne bacteria. Tick species were identified based on morphologic and genetic criteria. Detection of tick-borne bacteria belonging to Rickettsia, Anaplasma, Ehrlichia and Borrelia genera was performed by PCRs. Our ticks included 91 Amblyomma multipunctum, 4 Amblyomma spp., 60 Rhipicephalus microplus, 5 Ixodes spp. and 1 Ixodes boliviensis. A potential Candidatus Rickettsia species closest to Rickettsia monacensis and Rickettsia tamurae (designated Rickettsia sp. 12G1) was detected in 3 R. microplus (3/57, 5.3%). In addition, Anaplasma spp., assigned at least to Anaplasma phagocytophilum (or closely related genotypes) and Anaplasma marginale, were found in 2 A. multipunctum (2/87, 2.3%) and 13 R. microplus (13/57, 22.8%). This is the first description of Rickettsia sp. in ticks from Ecuador, and the analyses of sequences suggest the presence of a potential novel Rickettsia species. Ecuadorian ticks from Andear tapirs, cattle and vegetation belonging to Amblyomma and Rhipicephalus genera were infected with Anaplasmataceae. Ehrlichia spp. and Borrelia burgdorferi sensu lato were not found in any ticks.

  15. Properties of Carry Value Transformation

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    Suryakanta Pal

    2012-01-01

    Full Text Available Carry Value Transformation (CVT is a model of discrete deterministic dynamical system. In the present study, it has been proved that (1 the sum of any two nonnegative integers is the same as the sum of their CVT and XOR values. (2 the number of iterations leading to either CVT=0 or XOR=0 does not exceed the maximum of the lengths of the two addenda expressed as binary strings. A similar process of addition of modified Carry Value Transformation (MCVT and XOR requires a maximum of two iterations for MCVT to be zero. (3 an equivalence relation is shown to exist on Z×Z which divides the CV table into disjoint equivalence classes.

  16. Catalase is a determinant of the colonization and transovarial transmission of Rickettsia parkeri in the Gulf Coast tick Amblyomma maculatum.

    Science.gov (United States)

    Budachetri, K; Kumar, D; Karim, S

    2017-08-01

    The Gulf Coast tick (Amblyomma maculatum) has evolved as a competent vector of the spotted-fever group rickettsia, Rickettsia parkeri. In this study, the functional role of catalase, an enzyme responsible for the degradation of toxic hydrogen peroxide, in the colonization of the tick vector by R. parkeri and transovarial transmission of this pathogen to the next tick generation, was investigated. Catalase gene (CAT) expression in midgut, salivary glands and ovarian tissues exhibited a 2-11-fold increase in transcription level upon R. parkeri infection. Depletion of CAT transcripts using an RNA-interference approach significantly reduced R. parkeri infection levels in midgut and salivary gland tissues by 53-63%. The role of CAT in transovarial transmission of R. parkeri was confirmed by simultaneously blocking the transcript and the enzyme by injecting double-stranded RNA for CAT and a catalase inhibitor (3-amino-1,2,4-triazole) into gravid females. Simultaneous inhibition of the CAT transcript and the enzyme significantly reduced the egg conversion ratio with a 44% reduction of R. parkeri transovarial transmission. These data suggest that catalase is required for rickettsial colonization of the tick vector and transovarial transmission to the next generation. © 2017 The Royal Entomological Society.

  17. Serum levels of copper, selenium and manganese in forestry workers testing IgG positive for Brucella, Borrelia, and Rickettsia.

    Science.gov (United States)

    Abbate, Simona; Giorgianni, Concetto; D'Arrigo, Graziella; Brecciaroli, Renato; Catanoso, Rosaria; Alibrando, Carmela; Spatari, Giovanna; Gangemi, Silvia; Abbate, Carmelo

    2013-09-01

    The aim of this study is to measure the alterations in the trace levels of serum copper (Cu), selenium (Se), and manganese (Mn) in forestry workers testing immunoglobulin G (IgG)-positive for Brucella, Borrelia, and Rickettsia. The study was conducted on a sample of 758 subjects (560 male and 198 female). All the subjects underwent medical examinations, which investigated particularly the presence of clinical signs compatible with zoonoses, and routine blood tests from venous blood sample, which tested previous immunisation versus cited microorganisms and serum concentration of Cu, Se, and Mn. The subjects were divided according to IgG positivity versus the cited microorganisms. The group of subjects with IgG positive versus Brucella showed statistically significant higher Cu levels than controls, while the Mn levels were not; the group of subjects with IgG positive versus Rickettsia showed higher levels of all three tested metals. The concentration of the examined metals did not show statistically significant difference between IgG-positive subjects versus subjects with Borrelia compared to controls. These data could confirm the role of both Cu and Se  in the regulation of immune response.

  18. The genome sequence of Rickettsia felis identifies the first putative conjugative plasmid in an obligate intracellular parasite.

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    2005-08-01

    Full Text Available We sequenced the genome of Rickettsia felis, a flea-associated obligate intracellular alpha-proteobacterium causing spotted fever in humans. Besides a circular chromosome of 1,485,148 bp, R. felis exhibits the first putative conjugative plasmid identified among obligate intracellular bacteria. This plasmid is found in a short (39,263 bp and a long (62,829 bp form. R. felis contrasts with previously sequenced Rickettsia in terms of many other features, including a number of transposases, several chromosomal toxin-antitoxin genes, many more spoT genes, and a very large number of ankyrin- and tetratricopeptide-motif-containing genes. Host-invasion-related genes for patatin and RickA were found. Several phenotypes predicted from genome analysis were experimentally tested: conjugative pili and mating were observed, as well as beta-lactamase activity, actin-polymerization-driven mobility, and hemolytic properties. Our study demonstrates that complete genome sequencing is the fastest approach to reveal phenotypic characters of recently cultured obligate intracellular bacteria.

  19. The genome sequence of Rickettsia felis identifies the first putative conjugative plasmid in an obligate intracellular parasite.

    Science.gov (United States)

    Ogata, Hiroyuki; Renesto, Patricia; Audic, Stéphane; Robert, Catherine; Blanc, Guillaume; Fournier, Pierre-Edouard; Parinello, Hugues; Claverie, Jean-Michel; Raoult, Didier

    2005-08-01

    We sequenced the genome of Rickettsia felis, a flea-associated obligate intracellular alpha-proteobacterium causing spotted fever in humans. Besides a circular chromosome of 1,485,148 bp, R. felis exhibits the first putative conjugative plasmid identified among obligate intracellular bacteria. This plasmid is found in a short (39,263 bp) and a long (62,829 bp) form. R. felis contrasts with previously sequenced Rickettsia in terms of many other features, including a number of transposases, several chromosomal toxin-antitoxin genes, many more spoT genes, and a very large number of ankyrin- and tetratricopeptide-motif-containing genes. Host-invasion-related genes for patatin and RickA were found. Several phenotypes predicted from genome analysis were experimentally tested: conjugative pili and mating were observed, as well as beta-lactamase activity, actin-polymerization-driven mobility, and hemolytic properties. Our study demonstrates that complete genome sequencing is the fastest approach to reveal phenotypic characters of recently cultured obligate intracellular bacteria.

  20. Molecular evidence for the presence of Rickettsia Felis in the feces of wild-living African apes.

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    Alpha Kabinet Keita

    Full Text Available Rickettsia felis is a common emerging pathogen detected in mosquitoes in sub-Saharan Africa. We hypothesized that, as with malaria, great apes may be exposed to the infectious bite of infected mosquitoes and release R. felis DNA in their feces.We conducted a study of 17 forest sites in Central Africa, testing 1,028 fecal samples from 313 chimpanzees, 430 gorillas and 285 bonobos. The presence of rickettsial DNA was investigated by specific quantitative real-time PCR. Positive results were confirmed by a second PCR using primers and a probe targeting a specific gene for R. felis. All positive samples were sequenced.Overall, 113 samples (11% were positive for the Rickettsia-specific gltA gene, including 25 (22% that were positive for R. felis. The citrate synthase (gltA sequence and outer membrane protein A (ompA sequence analysis indicated 99% identity at the nucleotide level to R. felis. The 88 other samples (78% were negative using R. felis-specific qPCR and were compatible with R. felis-like organisms.For the first time, we detected R. felis in wild-living ape feces. This non invasive detection of human pathogens in endangered species opens up new possibilities in the molecular epidemiology and evolutionary analysis of infectious diseases, beside HIV and malaria.

  1. Structure of 3-ketoacyl-(acyl-carrier-protein) reductase from Rickettsia prowazekii at 2.25 Å resolution

    International Nuclear Information System (INIS)

    Subramanian, Sandhya; Abendroth, Jan; Phan, Isabelle Q. H.; Olsen, Christian; Staker, Bart L.; Napuli, A.; Van Voorhis, Wesley C.; Stacy, Robin; Myler, Peter J.

    2011-01-01

    The R. prowazekii 3-ketoacyl-(acyl-carrier-protein) reductase is similar to those from other prokaryotic pathogens but differs significantly from the mammalian orthologue, strengthening its case as a potential drug target. Rickettsia prowazekii, a parasitic Gram-negative bacterium, is in the second-highest biodefense category of pathogens of the National Institute of Allergy and Infectious Diseases, but only a handful of structures have been deposited in the PDB for this bacterium; to date, all of these have been solved by the SSGCID. Owing to its small genome (about 800 protein-coding genes), it relies on the host for many basic biosynthetic processes, hindering the identification of potential antipathogenic drug targets. However, like many bacteria and plants, its metabolism does depend upon the type II fatty-acid synthesis (FAS) pathway for lipogenesis, whereas the predominant form of fatty-acid biosynthesis in humans is via the type I pathway. Here, the structure of the third enzyme in the FAS pathway, 3-ketoacyl-(acyl-carrier-protein) reductase, is reported at a resolution of 2.25 Å. Its fold is highly similar to those of the existing structures from some well characterized pathogens, such as Mycobacterium tuberculosis and Burkholderia pseudomallei, but differs significantly from the analogous mammalian structure. Hence, drugs known to target the enzymes of pathogenic bacteria may serve as potential leads against Rickettsia, which is responsible for spotted fever and typhus and is found throughout the world

  2. Structure of fumarate hydratase from Rickettsia prowazekii, the agent of typhus and suspected relative of the mitochondria

    International Nuclear Information System (INIS)

    Phan, Isabelle; Subramanian, Sandhya; Olsen, Christian; Edwards, Thomas E.; Guo, Wenjin; Zhang, Yang; Van Voorhis, Wesley C.; Stewart, Lance J.; Myler, Peter J.

    2011-01-01

    Fumarate hydratase is an enzyme of the tricarboxylic acid cycle, one of the metabolic pathways characteristic of the mitochondria. The structure of R. prowazekii class II fumarate hydratase is reported at 2.4 Å resolution and is compared with the available structure of the human homolog. Rickettsiae are obligate intracellular parasites of eukaryotic cells that are the causative agents responsible for spotted fever and typhus. Their small genome (about 800 protein-coding genes) is highly conserved across species and has been postulated as the ancestor of the mitochondria. No genes that are required for glycolysis are found in the Rickettsia prowazekii or mitochondrial genomes, but a complete set of genes encoding components of the tricarboxylic acid cycle and the respiratory-chain complex is found in both. A 2.4 Å resolution crystal structure of R. prowazekii fumarate hydratase, an enzyme catalyzing the third step of the tricarboxylic acid cycle pathway that ultimately converts phosphoenolpyruvate into succinyl-CoA, has been solved. A structure alignment with human mitochondrial fumarate hydratase highlights the close similarity between R. prowazekii and mitochondrial enzymes

  3. Detection of Rickettsia helvetica and Candidatus R. tarasevichiae DNA in Ixodes persulcatus ticks collected in Northeastern European Russia (Komi Republic).

    Science.gov (United States)

    Kartashov, Mikhail Yu; Glushkova, Ludmila I; Mikryukova, Tamara P; Korabelnikov, Igor V; Egorova, Yulia I; Tupota, Natalia L; Protopopova, Elena V; Konovalova, Svetlana N; Ternovoi, Vladimir A; Loktev, Valery B

    2017-06-01

    The number of tick-borne infections in the northern European regions of Russia has increased considerably in the last years. In the present study, 676 unfed adult Ixodes persulcatus ticks were collected in the Komi Republic from 2011 to 2013 to study tick-borne rickettsioses. Rickettsia spp. DNA was detected by PCR in 51 (7.6%) ticks. The nucleotide sequence analysis of gltA fragments (765bp) from 51 ticks indicated that 60.8% and 39.2% of the ticks were infected with Rickettsia helvetica and Candidatus R. tarasevichiae, respectively. The gltA fragments showed 100% identity with those of Candidatus R. tarasevichiae previously discovered in Siberia and China, whereas R. helvetica showed 99.9% sequence identity with European isolates. The ompB had 8 nucleotide substitutions, 6 of which resulted in amino acid substitutions. In the sca9 gene, 3 nucleotide substitutions were detected, and only one resulted in amino acid substitution. The smpA, ompW, and β-lactamase genes of R. helvetica also showed a high level of sequence identity. Copyright © 2017 Elsevier GmbH. All rights reserved.

  4. Associations between coinfection prevalence of Borrelia lusitaniae, Anaplasma sp., and Rickettsia sp. in hard ticks feeding on reptile hosts.

    Science.gov (United States)

    Václav, Radovan; Ficová, Martina; Prokop, Pavol; Betáková, Tatiana

    2011-02-01

    An increasing number of studies reveal that ticks and their hosts are infected with multiple pathogens, suggesting that coinfection might be frequent for both vectors and wild reservoir hosts. Whereas the examination of associations between coinfecting pathogen agents in natural host-vector-pathogen systems is a prerequisite for a better understanding of disease maintenance and transmission, the associations between pathogens within vectors or hosts are seldom explicitly examined. We examined the prevalence of pathogen agents and the patterns of associations between them under natural conditions, using a previously unexamined host-vector-pathogen system--green lizards Lacerta viridis, hard ticks Ixodes ricinus, and Borrelia, Anaplasma, and Rickettsia pathogens. We found that immature ticks infesting a temperate lizard species in Central Europe were infected with multiple pathogens. Considering I. ricinus nymphs and larvae, the prevalence of Anaplasma, Borrelia, and Rickettsia was 13.1% and 8.7%, 12.8% and 1.3%, and 4.5% and 2.7%, respectively. The patterns of pathogen prevalence and observed coinfection rates suggest that the risk of tick infection with one pathogen is not independent of other pathogens. Our results indicate that Anaplasma can play a role in suppressing the transmission of Borrelia to tick vectors. Overall, however, positive effects of Borrelia on Anaplasma seem to prevail as judged by higher-than-expected Borrelia-Anaplasma coinfection rates.

  5. Rickettsia parkeri invasion of diverse host cells involves an Arp2/3 complex, WAVE complex and Rho-family GTPase-dependent pathway.

    Science.gov (United States)

    Reed, Shawna C O; Serio, Alisa W; Welch, Matthew D

    2012-04-01

    Rickettsiae are obligate intracellular pathogens that are transmitted to humans by arthropod vectors and cause diseases such as spotted fever and typhus. Although rickettsiae require the host cell actin cytoskeleton for invasion, the cytoskeletal proteins that mediate this process have not been completely described. To identify the host factors important during cell invasion by Rickettsia parkeri, a member of the spotted fever group (SFG), we performed an RNAi screen targeting 105 proteins in Drosophila melanogaster S2R+ cells. The screen identified 21 core proteins important for invasion, including the GTPases Rac1 and Rac2, the WAVE nucleation-promoting factor complex and the Arp2/3 complex. In mammalian cells, including endothelial cells, the natural targets of R. parkeri, the Arp2/3 complex was also crucial for invasion, while requirements for WAVE2 as well as Rho GTPases depended on the particular cell type. We propose that R. parkeri invades S2R+ arthropod cells through a primary pathway leading to actin nucleation, whereas invasion of mammalian endothelial cells occurs via redundant pathways that converge on the host Arp2/3 complex. Our results reveal a key role for the WAVE and Arp2/3 complexes, as well as a higher degree of variation than previously appreciated in actin nucleation pathways activated during Rickettsia invasion. © 2011 Blackwell Publishing Ltd.

  6. Genetic Diversity of the Invasive Gall Wasp Leptocybe invasa (Hymenoptera: Eulophidae) and of its Rickettsia Endosymbiont, and Associated Sex-Ratio Differences.

    Science.gov (United States)

    Nugnes, Francesco; Gebiola, Marco; Monti, Maurilia Maria; Gualtieri, Liberata; Giorgini, Massimo; Wang, Jianguo; Bernardo, Umberto

    2015-01-01

    The blue-gum chalcid Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae) is a gall wasp pest of Eucalyptus species, likely native to Australia. Over the past 15 years it has invaded 39 countries on all continents where eucalypts are grown. The worldwide invasion of the blue gum chalcid was attributed to a single thelytokous morphospecies formally described in 2004. Subsequently, however, males have been recorded in several countries and the sex ratio of field populations has been found to be highly variable in different areas. In order to find an explanation for such sex ratio differences, populations of L. invasa from a broad geographical area were screened for the symbionts currently known as reproductive manipulators, and both wasps and symbionts were genetically characterized using multiple genes. Molecular analyses suggested that L. invasa is in fact a complex of two cryptic species involved in the rapid and efficient spread of the wasp, the first recovered from the Mediterranean region and South America, the latter from China. All screened specimens were infected by endosymbiotic bacteria belonging to the genus Rickettsia. Two closely related Rickettsia strains were found, each infecting one of the two putative cryptic species of L. invasa and associated with different average sex ratios. Rickettsia were found to be localized in the female reproductive tissues and transovarially transmitted, suggesting a possible role of Rickettsia as the causal agent of thelytokous parthenogenesis in L. invasa. Implications for the variation of sex ratio and for the management of L. invasa are discussed.

  7. Molecular surveillance of spotted fever group rickettsioses in wildlife and detection of Rickettsia sibirica in a Topi (Damaliscus lunatus ssp. jimela in Kenya

    Directory of Open Access Journals (Sweden)

    David Ndeereh

    2017-01-01

    Full Text Available Spotted fever group rickettsioses are a group of tick-borne zoonotic diseases caused by intracellular bacteria of the genus Rickettsia. The diseases are widely reported amongst international travellers returning from most sub-Saharan Africa with fever, yet their importance in local populations largely remains unknown. Although this has started to change and recently there have been increasing reports of the diseases in livestock, ticks and humans in Kenya, they have not been investigated in wildlife. We examined the presence, prevalence and species of Rickettsia present in wildlife in two regions of Kenya with a unique human–wildlife–livestock interface. For this purpose, 79 wild animals in Laikipia County and 73 in Maasai Mara National Reserve were sampled. DNA extracted from blood was tested using the polymerase chain reaction (PCR to amplify the intergenic spacer rpmE-tRNAfMet and the citrate synthase-encoding gene gltA. Rickettsial DNA was detected in 2 of the 79 (2.5% animals in Laikipia and 4 of the 73 (5.5% in Maasai Mara. The PCR-positive amplicons of the gltA gene were sequenced to determine the detected Rickettsia species. This revealed Rickettsia sibirica in a Topi (Damaliscus lunatus ssp. jimela. This is the first report of spotted fever group rickettsioses in wildlife and the first to report R. sibirica in Kenya. The finding demonstrates the potential role of wild animals in the circulation of the diseases.

  8. Genetic Diversity of the Invasive Gall Wasp Leptocybe invasa (Hymenoptera: Eulophidae and of its Rickettsia Endosymbiont, and Associated Sex-Ratio Differences.

    Directory of Open Access Journals (Sweden)

    Francesco Nugnes

    Full Text Available The blue-gum chalcid Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae is a gall wasp pest of Eucalyptus species, likely native to Australia. Over the past 15 years it has invaded 39 countries on all continents where eucalypts are grown. The worldwide invasion of the blue gum chalcid was attributed to a single thelytokous morphospecies formally described in 2004. Subsequently, however, males have been recorded in several countries and the sex ratio of field populations has been found to be highly variable in different areas. In order to find an explanation for such sex ratio differences, populations of L. invasa from a broad geographical area were screened for the symbionts currently known as reproductive manipulators, and both wasps and symbionts were genetically characterized using multiple genes. Molecular analyses suggested that L. invasa is in fact a complex of two cryptic species involved in the rapid and efficient spread of the wasp, the first recovered from the Mediterranean region and South America, the latter from China. All screened specimens were infected by endosymbiotic bacteria belonging to the genus Rickettsia. Two closely related Rickettsia strains were found, each infecting one of the two putative cryptic species of L. invasa and associated with different average sex ratios. Rickettsia were found to be localized in the female reproductive tissues and transovarially transmitted, suggesting a possible role of Rickettsia as the causal agent of thelytokous parthenogenesis in L. invasa. Implications for the variation of sex ratio and for the management of L. invasa are discussed.

  9. 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.

  10. How honey bees carry pollen

    Science.gov (United States)

    Matherne, Marguerite E.; Anyanwu, Gabriel; Leavey, Jennifer K.; Hu, David L.

    2017-11-01

    Honey bees are the tanker of the skies, carrying thirty percent of their weight in pollen per foraging trip using specialized orifices on their body. How do they manage to hang onto those pesky pollen grains? In this experimental study, we investigate the adhesion force of pollen to the honeybee. To affix pollen to themselves, honey bees form a suspension of pollen in nectar, creating a putty-like pollen basket that is skewered by leg hairs. We use tensile tests to show that the viscous force of the pollen basket is more than ten times the honeybee's flight force. This work may provide inspiration for the design of robotic flying pollinators.

  11. Loren Shriver carries Olympic torch

    Science.gov (United States)

    1996-01-01

    KSC Shuttle Operations Manager Loren J. Shriver proudly displays the Olympic torch that he carried to the top of Launch Pad 39A as his contribution to the July 7, 1996 KSC Olympic torch relay effort. Nineteen other KSC runners also participated in the relay effort at the Center. The Olympic torch arrived at KSC at 1:40 p.m. and traveled a 20-mile course to the pad and then out to the KSC visitor Center. The Space Shuttle Atlantis is behind Shriver, poised for the STS-79 mission, which will feature the fourth docking of the Shuttle with the Russian Mir space station.

  12. Are Apodemus spp. mice and Myodes glareolus reservoirs for Borrelia miyamotoi, Candidatus Neoehrlichia mikurensis, Rickettsia helvetica, R. monacensis and Anaplasma phagocytophilum?

    Science.gov (United States)

    Burri, C; Schumann, O; Schumann, C; Gern, L

    2014-04-01

    In Europe, in addition to Borrelia burgdorferi sensu lato and tick-borne encephalitis (TBE) virus, other zoonotic pathogens, like B. miyamotoi, a species related to the relapsing fever spirochaetes, Candidatus Neoehrlichia mikurensis (N. mikurensis), Rickettsia helvetica, Rickettsia monacensis, and Anaplasma phagocytophilum have been reported in the ixodid tick Ixodes ricinus. No study was conducted to identify reservoir hosts for these pathogens. Here, we investigated the role played by wild rodents in the natural transmission cycle of B. miyamotoi, N. mikurensis, R. helvetica, R. monacensis, and A. phagocytophilum in Switzerland. In 2011 and 2012, small mammals were captured in an area where these pathogens occur in questing ticks. Ixodes ricinus ticks infesting captured small mammals were analysed after their moult by PCR followed by reverse line blot to detect the different pathogens. Xenodiagnostic larvae were used to evaluate the role of rodents as reservoirs and analysed after their moult. Most of the 108 captured rodents (95.4%) were infested by I. ricinus ticks; 4.9%, 3.9%, 24.0%, and 0% of the rodents were infested by Borrelia, N. mikurensis, Rickettsia spp., and A. phagocytophilum-infected larvae, respectively. Borrelia afzelii, B. miyamotoi, N. mikurensis, Rickettsia spp., and A. phagocytophilum were detected in 2.8%, 0.17%, 2.6%, 6.8%, and 0% of the ticks attached to rodents, respectively. Borrelia afzelii was transmitted by 4 rodents to 41.2% of the xenodiagnostic ticks, B. miyamotoi by 3 rodents to 23.8%, and N. mikurensis was transmitted by 6 rodents to 41.0% of the xenodiagnostic ticks. None of the tested rodent transmitted Rickettsia spp. or A. phagocytophilum to I. ricinus xenodiagnostic larvae. This study showed that rodents are reservoir hosts for B. miyamotoi and N. mikurensis in Europe. Copyright © 2014 Elsevier GmbH. All rights reserved.

  13. Development of Recombinase Polymerase Amplification Assays for Detection of Orientia tsutsugamushi or Rickettsia typhi.

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    Chien-Chung Chao

    Full Text Available Sensitive, specific and rapid diagnostic tests for the detection of Orientia tsutsugamushi (O. tsutsugamushi and Rickettsia typhi (R. typhi, the causative agents of scrub typhus and murine typhus, respectively, are necessary to accurately and promptly diagnose patients and ensure that they receive proper treatment. Recombinase polymerase amplification (RPA assays using a lateral flow test (RPA-nfo and real-time fluorescent detection (RPA-exo were developed targeting the 47-kDa gene of O. tsutsugamushi or 17 kDa gene of R. typhi. The RPA assay was capable of detecting O. tsutsugamushi or R. typhi at levels comparable to that of the quantitative PCR method. Both the RPA-nfo and RPA-exo methods performed similarly with regards to sensitivity when detecting the 17 kDa gene of R. typhi. On the contrary, RPA-exo performed better than RPA-nfo in detecting the 47 kDa gene of O. tsutsugamushi. The clinical performance of the O. tsutsugamushi RPA assay was evaluated using either human patient samples or infected mouse samples. Eight out of ten PCR confirmed positives were determined positive by RPA, and all PCR confirmed negative samples were negative by RPA. Similar results were obtained for R. typhi spiked patient sera. The assays were able to differentiate O. tsutsugamushi and R. typhi from other phylogenetically related bacteria as well as mouse and human DNA. Furthermore, the RPA-nfo reaction was completed in 20 minutes at 37°C followed by a 10 minute incubation at room temperature for development of an immunochromatographic strip. The RPA-exo reaction was completed in 20 minutes at 39°C. The implementation of a cross contamination proof cassette to detect the RPA-nfo fluorescent amplicons provided an alternative to regular lateral flow detection strips, which are more prone to cross contamination. The RPA assays provide a highly time-efficient, sensitive and specific alternative to other methods for diagnosing scrub typhus or murine typhus.

  14. Why do dolphins carry sponges?

    Science.gov (United States)

    Mann, Janet; Sargeant, Brooke L; Watson-Capps, Jana J; Gibson, Quincy A; Heithaus, Michael R; Connor, Richard C; Patterson, Eric

    2008-01-01

    Tool use is rare in wild animals, but of widespread interest because of its relationship to animal cognition, social learning and culture. Despite such attention, quantifying the costs and benefits of tool use has been difficult, largely because if tool use occurs, all population members typically exhibit the behavior. In Shark Bay, Australia, only a subset of the bottlenose dolphin population uses marine sponges as tools, providing an opportunity to assess both proximate and ultimate costs and benefits and document patterns of transmission. We compared sponge-carrying (sponger) females to non-sponge-carrying (non-sponger) females and show that spongers were more solitary, spent more time in deep water channel habitats, dived for longer durations, and devoted more time to foraging than non-spongers; and, even with these potential proximate costs, calving success of sponger females was not significantly different from non-spongers. We also show a clear female-bias in the ontogeny of sponging. With a solitary lifestyle, specialization, and high foraging demands, spongers used tools more than any non-human animal. We suggest that the ecological, social, and developmental mechanisms involved likely (1) help explain the high intrapopulation variation in female behaviour, (2) indicate tradeoffs (e.g., time allocation) between ecological and social factors and, (3) constrain the spread of this innovation to primarily vertical transmission.

  15. Why do dolphins carry sponges?

    Directory of Open Access Journals (Sweden)

    Janet Mann

    Full Text Available Tool use is rare in wild animals, but of widespread interest because of its relationship to animal cognition, social learning and culture. Despite such attention, quantifying the costs and benefits of tool use has been difficult, largely because if tool use occurs, all population members typically exhibit the behavior. In Shark Bay, Australia, only a subset of the bottlenose dolphin population uses marine sponges as tools, providing an opportunity to assess both proximate and ultimate costs and benefits and document patterns of transmission. We compared sponge-carrying (sponger females to non-sponge-carrying (non-sponger females and show that spongers were more solitary, spent more time in deep water channel habitats, dived for longer durations, and devoted more time to foraging than non-spongers; and, even with these potential proximate costs, calving success of sponger females was not significantly different from non-spongers. We also show a clear female-bias in the ontogeny of sponging. With a solitary lifestyle, specialization, and high foraging demands, spongers used tools more than any non-human animal. We suggest that the ecological, social, and developmental mechanisms involved likely (1 help explain the high intrapopulation variation in female behaviour, (2 indicate tradeoffs (e.g., time allocation between ecological and social factors and, (3 constrain the spread of this innovation to primarily vertical transmission.

  16. Novelties that change carrying capacity.

    Science.gov (United States)

    Erwin, Douglas H

    2012-09-01

    Comparative developmental studies have revealed a rich array of details about the patterns and processes of morphological change in animals and increasingly in plants. But, applying these insights to the study of major episodes of evolutionary innovation requires understanding how these novel morphologies become established and sufficiently abundant (either as individuals within a species or as a clade of species) to be preserved in the fossil record, and, in many cases, to influence ecological processes. Evolutionary novelties may: (1) disappear without changing the species; (2) be associated with the generation (through selection or drift) of a new species; and if the latter (3) may or may not become ecologically significant. Only the latter are commonly preserved in the fossil record. These alternatives mirror the distinction among historians of technology between innovation and invention. Here, I argue that specific sorts of evolutionary inventions drive ecological transformation, essentially constructing an environment for themselves and ancillary organisms through ecological spillover effects, increasing the "carrying capacity" of an ecosystem. Copyright © 2011 Wiley Periodicals, Inc.

  17. Rickettsia parkeri Rickettsiosis in Different Ecological Regions of Argentina and Its Association with Amblyomma tigrinum as a Potential Vector

    Science.gov (United States)

    Romer, Yamila; Nava, Santiago; Govedic, Francisco; Cicuttin, Gabriel; Denison, Amy M.; Singleton, Joseph; Kelly, Aubree J.; Kato, Cecilia Y.; Paddock, Christopher D.

    2014-01-01

    Rickettsia parkeri, a newly recognized tick-borne pathogen of humans in the Americas, is a confirmed cause of spotted fever group rickettsiosis in Argentina. Until recently, almost all cases of R. parkeri rickettsiosis in Argentina have originated from the Paraná River Delta, where entomological surveys have identified populations of R. parkeri-infected Amblyomma triste ticks. In this report, we describe confirmed cases of R. parkeri rickettsiosis from Córdoba and La Rioja provinces, which are located several hundred kilometers inland, and in a more arid ecological region, where A. triste ticks do not occur. Additionally, we identified questing A. tigrinum ticks naturally infected with R. parkeri in Córdoba province. These data provide evidence that another human-biting tick species serves as a potential vector of R. parkeri in Argentina and possibly, other countries of South America. PMID:25349376

  18. Study of infection by Rickettsiae of the spotted fever group in humans and ticks in an urban park located in the City of Londrina, State of Paraná, Brazil Estudo da infecção por Rickettsias do grupo da febre maculosa em humanos e carrapatos de um parque urbano na Cidade de Londrina, Estado do Paraná

    Directory of Open Access Journals (Sweden)

    Roberta Santos Toledo

    2011-06-01

    Full Text Available INTRODUCTION: Spotted fevers are emerging zoonoses caused by Rickettsia species in the spotted fever group (SFG. Rickettsia rickettsii is the main etiologic agent of Brazilian spotted fever (BSF and it is transmitted by Amblyomma spp. ticks. METHODS: The study aimed to investigate SFG rickettsiae in the Arthur Thomas Municipal Park in Londrina, PR, by collecting free-living ticks and ticks from capybaras and blood samples from personnel working in these areas. Samples from A. dubitatum and A. cajennense were submitted for PCR in pools to analyze the Rickettsia spp. gltA (citrate synthase gene. RESULTS: All the pools analyzed were negative. Human sera were tested by indirect immunofluorescence assay with R. rickettsii and R. parkeri as antigens. Among the 34 sera analyzed, seven (20.6% were reactive for R. rickettsii: four of these had endpoint titers equal to 64, 2 titers were 128 and 1 titer was 256. None of the samples were reactive for R. parkeri. An epidemiological questionnaire was applied to the park staff, but no statistically significant associations were identified. CONCLUSIONS: The serological studies suggest the presence of Rickettsiae related to SFG that could be infecting the human population studied; however, analysis of the ticks collected was unable to determine which species may be involved in transmission to humans.INTRODUÇÃO: A febre maculosa é uma zoonose emergente causada por espécies de Rickettsia do grupo febre maculosa (GFM. Rickettsia rickettsii é o principal agente etiológico da febre maculosa brasileira (FMB e é transmitida por Amblyomma spp. MÉTODOS: Com o objetivo de obter informações sobre GFM Rickettsiae no Parque Municipal Arthur Thomas em Londrina, PR, carrapatos de vida livre e de capivaras foram coletados, assim como amostras de sangue das pessoas que trabalham no parque. A. dubitatum e A. cajennense foram submetidos à PCR em pools para analises de Rickettsia spp. gltA (citrate synthase gene

  19. Incidence of Male-Killing Rickettsia spp. (α-Proteobacteria) in the Ten-Spot Ladybird Beetle Adalia decempunctata L. (Coleoptera: Coccinellidae)

    Science.gov (United States)

    von der Schulenburg, J. Hinrich Graf; Habig, Michael; Sloggett, John J.; Webberley, K. Mary; Bertrand, Dominique; Hurst, Gregory D. D.; Majerus, Michael E. N.

    2001-01-01

    The diversity of endosymbiotic bacteria that kill male host offspring during embryogenesis and their frequencies in certain groups of host taxa suggest that the evolution of male killing and the subsequent spread of male-killing symbionts are primarily determined by host life history characteristics. We studied the 10-spot ladybird beetle, Adalia decempunctata L. (Coleoptera: Coccinellidae), in which male killing has not been recorded previously, to test this hypothesis, and we also assessed the evolution of the male killer identified by DNA sequence analysis. Our results show that A. decempunctata harbors male-killing Rickettsia (α-proteobacteria). Male-killing bacteria belonging to the genus Rickettsia have previously been reported only for the congeneric two-spot ladybird beetle, Adalia bipunctata L. Phylogenetic analysis of Rickettsia DNA sequences isolated from different populations of the two host species revealed a single origin of male killing in the genus Rickettsia. The data also indicated possible horizontal transfer of symbionts between host species. In addition, A. bipunctata is known to bear at least four different male-killing symbionts in its geographic range two of which coexist in the two locations from which A. decempunctata specimens were obtained for the present study. Since only a single male-killing taxon was found in A. decempunctata, we assume that the two closely related ladybird beetle species must differ in the number and/or geographic distribution of male killers. We discuss the importance of these findings to our understanding of the evolution and dynamics of symbiotic associations between male-killing bacteria and their insect hosts. PMID:11133455

  20. Transcriptional regulation of the gltA and tlc genes in Rickettsia prowazekii growing in a respiration-deficient host cell

    International Nuclear Information System (INIS)

    Cai, J.; Winkler, H.H.

    1997-01-01

    The regulation of the citrate synthase (gltA) and ATP/ADP translocase (tlc) genes of the obligate intracellular bacterium, Rickettsia prowazekii, was analyzed in rickettsia-infected respiration-deficient G14 cells. The level of the gltA mRNAII and the tlc mRNA was much lower in the total RNA isolated from the infected G 14 cells grown in 1 g/1 glucose (low glucose, GL) medium than in that from infected G 14 cells grown in 4.5 g/l glucose (high glucose, GH) medium. However, the level of the gltA mRNAI relative to 16 S rRNA was the same in GL and GH media. An increase in the level of the gltA mRNAII and the tlc mRNA could be observed as early as 2 hrs after shifting from GL to GH medium. We conclude that, under these experimental conditions, the tlc promoter and the gltA promoter P2, but not gltA promoter P1, were transcriptionally regulated. Key words: Rickettsia prowazekii; gltA gene; tlC gene; transcriptional regulation; G 14 cells (authors)

  1. Occurrence of Babesia spp., Rickettsia spp. and Bartonella spp. in Ixodes ricinus in Bavarian public parks, Germany

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    Mahling Monia

    2011-07-01

    Full Text Available Abstract Background Only limited information is available about the occurrence of ticks and tick-borne pathogens in public parks, which are areas strongly influenced by human beings. For this reason, Ixodes ricinus were collected in public parks of different Bavarian cities in a 2-year survey (2009 and 2010 and screened for DNA of Babesia spp., Rickettsia spp. and Bartonella spp. by PCR. Species identification was performed by sequence analysis and alignment with existing sequences in GenBank. Additionally, coinfections with Anaplasma phagocytophilum were investigated. Results The following prevalences were detected: Babesia spp.: 0.4% (n = 17, including one pool of two larvae in 2009 and 0.5 to 0.7% (n = 11, including one pool of five larvae in 2010; Rickettsia spp.: 6.4 to 7.7% (n = 285, including 16 pools of 76 larvae in 2009. DNA of Bartonella spp. in I. ricinus in Bavarian public parks could not be identified. Sequence analysis revealed the following species: Babesia sp. EU1 (n = 25, B. divergens (n = 1, B. divergens/capreoli (n = 1, B. gibsoni-like (n = 1, R. helvetica (n = 272, R. monacensis IrR/Munich (n = 12 and unspecified R. monacensis (n = 1. The majority of coinfections were R. helvetica with A. phagocytophilum (n = 27, but coinfections between Babesia spp. and A. phagocytophilum, or Babesia spp. and R. helvetica were also detected. Conclusions I. ricinus ticks in urban areas of Germany harbor several tick-borne pathogens and coinfections were also observed. Public parks are of particularly great interest regarding the epidemiology of tick-borne pathogens, because of differences in both the prevalence of pathogens in ticks as well as a varying species arrangement when compared to woodland areas. The record of DNA of a Babesia gibsoni-like pathogen detected in I. ricinus suggests that I. ricinus may harbor and transmit more Babesia spp. than previously known. Because of their high recreational value for human beings, urban green

  2. Occurrence of Babesia spp., Rickettsia spp. and Bartonella spp. in Ixodes ricinus in Bavarian public parks, Germany.

    Science.gov (United States)

    Schorn, Sabine; Pfister, Kurt; Reulen, Holger; Mahling, Monia; Silaghi, Cornelia

    2011-07-15

    Only limited information is available about the occurrence of ticks and tick-borne pathogens in public parks, which are areas strongly influenced by human beings. For this reason, Ixodes ricinus were collected in public parks of different Bavarian cities in a 2-year survey (2009 and 2010) and screened for DNA of Babesia spp., Rickettsia spp. and Bartonella spp. by PCR. Species identification was performed by sequence analysis and alignment with existing sequences in GenBank. Additionally, coinfections with Anaplasma phagocytophilum were investigated. The following prevalences were detected: Babesia spp.: 0.4% (n = 17, including one pool of two larvae) in 2009 and 0.5 to 0.7% (n = 11, including one pool of five larvae) in 2010; Rickettsia spp.: 6.4 to 7.7% (n = 285, including 16 pools of 76 larvae) in 2009. DNA of Bartonella spp. in I. ricinus in Bavarian public parks could not be identified. Sequence analysis revealed the following species: Babesia sp. EU1 (n = 25), B. divergens (n = 1), B. divergens/capreoli (n = 1), B. gibsoni-like (n = 1), R. helvetica (n = 272), R. monacensis IrR/Munich (n = 12) and unspecified R. monacensis (n = 1). The majority of coinfections were R. helvetica with A. phagocytophilum (n = 27), but coinfections between Babesia spp. and A. phagocytophilum, or Babesia spp. and R. helvetica were also detected. I. ricinus ticks in urban areas of Germany harbor several tick-borne pathogens and coinfections were also observed. Public parks are of particularly great interest regarding the epidemiology of tick-borne pathogens, because of differences in both the prevalence of pathogens in ticks as well as a varying species arrangement when compared to woodland areas. The record of DNA of a Babesia gibsoni-like pathogen detected in I. ricinus suggests that I. ricinus may harbor and transmit more Babesia spp. than previously known. Because of their high recreational value for human beings, urban green areas are likely to remain in the research focus on

  3. Detecção de proteínas imunorreativas de Rickettsia sp. cepa Mata Atlântica

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    Caroline S. Oliveira

    Full Text Available RESUMO: A Febre Maculosa Brasileira (FMB é uma doença infecciosa, transmitida por carrapatos ao homem. Uma nova riquetsiose humana foi descrita como causadora de Febre Maculosa no Estado de São Paulo, sendo denominada de Rickettsia sp. cepa Mata Atlântica. O presente trabalho teve como objetivo detectar e identificar proteínas com potencial de estimular o sistema imune de hospedeiro mamífero, desta nova cepa descrita. Para tanto, foi realizado a extração proteica total de Rickettsia sp. cepa Mata Atlântica. As proteínas extraídas foram fracionadas por eletroforese. As bandas proteicas foram transferidas para membranas de nitrocelulose por migração elétrica e submetidas à técnica de Western-blot, para detecção proteica. Ao todo sete proteínas imunorreativas foram detectadas. Duas proteínas apresentaram maior abundancia, com peso molecular, de 200 e 130 kDa respectivamente. Através da comparação de mapas proteômicos existentes e pelo peso molecular que estas proteínas apresentaram, sugere-se que as duas proteínas detectadas representem rOmpA (200 kDa e rOmpB (130 kDa. As demais proteínas detectadas apresentaram menor ocorrência e peso molecular inferior a 78 kDa, podendo representar membros da família de antígenos de superfície celular (Sca - Surface cell antigen. As proteínas detectadas poderão servir como base de estudo na elaboração de métodos diagnósticos sensíveis e específicos, no desenvolvimento de vacinas, além de possibilitarem novos estudos para terapias mais eficazes.

  4. Should women carry their antenatal records?

    OpenAIRE

    Draper, J; Field, S; Thomas, H; Hare, M J

    1986-01-01

    A study of women's views on carrying their medical records during their pregnancy was conducted in Cambridge in 1982. Eighty eight women who were given their full records were compared with a control group of 83 women who carried the traditional cooperation card, both groups answering postal questionnaires about the advantages and disadvantages of carrying their respective records. Most women found advantages in carrying the complete record, although it was too large to carry for practical pu...

  5. The enzootic life-cycle of Borrelia burgdorferi (sensu lato) and tick-borne rickettsiae: an epidemiological study on wild-living small mammals and their ticks from Saxony, Germany.

    Science.gov (United States)

    Obiegala, Anna; Król, Nina; Oltersdorf, Carolin; Nader, Julian; Pfeffer, Martin

    2017-03-13

    Borrelia burgdorferi (sensu lato) and rickettsiae of the spotted fever group are zoonotic tick-borne pathogens. While small mammals are confirmed reservoirs for certain Borrelia spp., little is known about the reservoirs for tick-borne rickettsiae. Between 2012 and 2014, ticks were collected from the vegetation and small mammals which were trapped in Saxony, Germany. DNA extracted from ticks and the small mammals' skin was analyzed for the presence of Rickettsia spp. and B. burgdorferi (s.l.) by qPCR targeting the gltA and p41 genes, respectively. Partial sequencing of the rickettsial ompB gene and an MLST of B. burgdorferi (s.l.) were conducted for species determination. In total, 673 small mammals belonging to eight species (Apodemus agrarius, n = 7; A. flavicollis, n = 214; Microtus arvalis, n = 8; Microtus agrestis, n = 1; Mustela nivalis, n = 2; Myodes glareolus, n = 435; Sorex araneus, n = 5; and Talpa europaea, n = 1) were collected and examined. In total, 916 questing ticks belonging to three species (Ixodes ricinus, n = 741; Dermacentor reticulatus, n = 174; and I. trianguliceps, n = 1) were collected. Of these, 474 ticks were further investigated. The prevalence for Rickettsia spp. and B. burgdorferi (s.l.) in the investigated small mammals was 25.3 and 31.2%, respectively. The chance of encountering Rickettsia spp. in M. glareolus was seven times higher for specimens infested with D. reticulatus than for those which were free of D. reticulatus (OR: 7.0; 95% CI: 3.3-14.7; P < 0.001). In total, 11.4% of questing I. ricinus and 70.5% of D. reticulatus were positive for Rickettsia spp. DNA of B. burgdorferi (s.l.) was detected only in I. ricinus (5.5%). Sequence analysis revealed 9 R. helvetica, 5 R. raoultii, and 1 R. felis obtained from 15 small mammal samples. Small mammals may serve as reservoirs for Rickettsia spp. and B. burgdorferi (s.l.). While the prevalence for Rickettsia spp. in M. glareolus is most

  6. Energetics of load carrying in Nepalese porters.

    Science.gov (United States)

    Bastien, Guillaume J; Schepens, Bénédicte; Willems, Patrick A; Heglund, Norman C

    2005-06-17

    Nepalese porters routinely carry head-supported loads equal to 100 to 200% of their body weight (Mb) for many days up and down steep mountain footpaths at high altitudes. Previous studies have shown that African women carry head-supported loads of up to 60% of their Mb far more economically than army recruits carrying equivalent loads in backpacks. Here we show that Nepalese porters carry heavier loads even more economically than African women. Female Nepalese porters, for example, carry on average loads that are 10% of their Mb heavier than the maximum loads carried by the African women, yet do so at a 25% smaller metabolic cost.

  7. 'Candidatus Megaira polyxenophila' gen. nov., sp. nov.: considerations on evolutionary history, host range and shift of early divergent rickettsiae.

    Directory of Open Access Journals (Sweden)

    Martina Schrallhammer

    Full Text Available "Neglected Rickettsiaceae" (i.e. those harboured by non-hematophagous eukaryotic hosts display greater phylogenetic variability and more widespread dispersal than pathogenic ones; yet, the knowledge about their actual host range and host shift mechanism is scarce. The present work reports the characterization following the full-cycle rRNA approach (SSU rRNA sequence, specific in situ hybridization, and ultrastructure of a novel rickettsial bacterium, herewith proposed as 'Candidatus Megaira polyxenophila' gen. nov., sp. nov. We found it in association with four different free-living ciliates (Diophrys oligothrix, Euplotes octocarinatus, Paramecium caudatum, and Spirostomum sp., all belonging to Alveolata, Ciliophora; furthermore it was recently observed as intracellular occurring in Carteria cerasiformis and Pleodorina japonica (Chlorophyceae, Chlorophyta. Phylogenetic analyses demonstrated the belonging of the candidate new genus to the family Rickettsiaceae (Alphaproteobacteria, Rickettsiales as a sister group of the genus Rickettsia. In situ observations revealed the ability of the candidate new species to colonize either nuclear or cytoplasmic compartments, depending on the host organism. The presence of the same bacterial species within different, evolutionary distant, hosts indicates that 'Candidatus Megaira polyxenophila' recently underwent several distinct host shifts, thus suggesting the existence of horizontal transmission pathways. We consider these findings as indicative of an unexpected spread of rickettsial infections in aquatic communities, possibly by means of trophic interactions, and hence propose a new interpretation of the origin and phylogenetic diversification of rickettsial bacteria.

  8. Local Dynamic Stability Associated with Load Carrying

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    Jian Liu

    2013-03-01

    Conclusion: Current study confirmed the sensitivity of local dynamic stability measure in load carrying situation. It was concluded that load carrying tasks were associated with declined local dynamic stability, which may result in increased risk of fall accident. This finding has implications in preventing fall accidents associated with occupational load carrying.

  9. Exposure and risk factors to coxiella burnetii, spotted fever group and typhus group Rickettsiae, and Bartonella henselae among volunteer blood donors in Namibia.

    Directory of Open Access Journals (Sweden)

    Bruce H Noden

    Full Text Available The role of pathogen-mediated febrile illness in sub-Saharan Africa is receiving more attention, especially in Southern Africa where four countries (including Namibia are actively working to eliminate malaria. With a high concentration of livestock and high rates of companion animal ownership, the influence of zoonotic bacterial diseases as causes of febrile illness in Namibia remains unknown.The aim of the study was to evaluate exposure to Coxiella burnetii, spotted fever and typhus group rickettsiae, and Bartonella henselae using IFA and ELISA (IgG in serum collected from 319 volunteer blood donors identified by the Blood Transfusion Service of Namibia (NAMBTS. Serum samples were linked to a basic questionnaire to identify possible risk factors. The majority of the participants (64.8% had extensive exposure to rural areas or farms. Results indicated a C. burnetii prevalence of 26.1% (screening titre 1∶16, and prevalence rates of 11.9% and 14.9% (screening titre 1∶100 for spotted fever group and typhus group rickettsiae, respectively. There was a significant spatial association between C. burnetii exposure and place of residence in southern Namibia (P0.012, especially cattle (P>0.006, were also significantly associated with C. burnetii exposure. Males were significantly more likely than females to have been exposed to spotted fever (P<0.013 and typhus (P<0.011 group rickettsiae. Three (2.9% samples were positive for B. henselae possibly indicating low levels of exposure to a pathogen never reported in Namibia.These results indicate that Namibians are exposed to pathogenic fever-causing bacteria, most of which have flea or tick vectors/reservoirs. The epidemiology of febrile illnesses in Namibia needs further evaluation in order to develop comprehensive local diagnostic and treatment algorithms.

  10. Measuring Social carrying Capacity: An Exploratory Study

    OpenAIRE

    López-Bonilla, Jesús Manuel; López-Bonilla, Luis Miguel

    2007-01-01

    The tourist carrying capacity commands a growing interest given that it is closely linked with sustainable tourist development. The justification of the utility of this concept is given by means of a simple and efficient methodological proposal, by analysing the social carrying capacity. To this end, an empirical application is carried out in the Western Andalusia. In some of the cases analysed, the satisfaction of the tourist is found to decline when the levels of the tourist use are higher ...

  11. Effect of Rickettsia felis Strain Variation on Infection, Transmission, and Fitness in the Cat Flea (Siphonaptera: Pulicidae).

    Science.gov (United States)

    Healy, Sean P; Brown, Lisa D; Hagstrom, Melena R; Foil, Lane D; Macaluso, Kevin R

    2017-07-01

    Rickettsia felis is a human pathogen transmitted by the cat flea, Ctenocephalides felis (Bouché) (str. LSU), as well as an obligate symbiont of the parthenogenic booklouse Liposcelis bostrychophila (Badonnel) (str. LSU-Lb). The influence of genetic variability in these two strains of R. felis on host specialization and fitness and possible resulting differences on infection and transmission kinetics in C. felis is unknown. Utilizing an artificial host system, cat fleas were exposed to a R. felis str. LSU-Lb-infected bloodmeal and monitored for infection at 7-d intervals for 28 d. Quantitative real-time PCR was used to determine rickettsial load and infection density in newly exposed cat fleas, and transmission frequency between cat fleas. The effect of persistent R. felis infection on cat flea F1 progeny was also assessed. At 7 d postexposure 76.7% of the cat fleas successfully acquired R. felis str. LSU-Lb. In R. felis str. LSU-Lb-exposed cat fleas, the mean infection load (6.15 × 106), infection density (0.76), and infection prevalence (91/114) were significantly greater than R. felis str. LSU infection load (3.09 × 106), infection density (0.68), and infection prevalence (76/113). A persistent R. felis str. LSU-Lb infection was detected for 28 d in adult cat fleas but neither female:male ratio distortion nor vertical transmission was observed in F1 progeny. While infection kinetics differed, with higher intensity associated with R. felis str. LSU-Lb, no distinct phenotype was observed in the F1 progeny. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  12. Assessment of Domestic Goats as Models for Experimental and Natural Infection with the North American Isolate of Rickettsia slovaca.

    Directory of Open Access Journals (Sweden)

    Nicole Lukovsky-Akhsanov

    Full Text Available Rickettsia slovaca is a tick-borne human pathogen that is associated with scalp eschars and neck lymphadenopathy known as tick-borne lymphadenopathy (TIBOLA or Dermacentor-borne necrosis erythema and lymphadenopathy (DEBONEL. Originally, R. slovaca was described in Eastern Europe, but since recognition of its pathogenicity, human cases have been reported throughout Europe. European vertebrate reservoirs of R. slovaca remain unknown, but feral swine and domestic goats have been found infected or seropositive for this pathogen. Recently, a rickettsial pathogen identical to R. slovaca was identified in, and isolated from, the American dog tick, Dermacentor variabilis. In previous experimental studies, this organism was found infectious to guinea pigs and transovarially transmissible in ticks. In this study, domestic goats (Capra hircus were experimentally inoculated with the North American isolate of this R. slovaca-like agent to assess their reservoir competence-the ability to acquire the pathogens and maintain transmission between infected and uninfected ticks. Goats were susceptible to infection as demonstrated by detection of the pathogen in skin biopsies and multiple internal tissues, but the only clinical sign of illness was transient fever noted in three out of four goats, and reactive lymphoid hyperplasia. On average, less than 5% of uninfected ticks acquired the pathogen while feeding upon infected goats. Although domestic goats are susceptible to the newly described North American isolate of R. slovaca, they are likely to play a minor role in the natural transmission cycle of this pathogen. Our results suggest that goats do not propagate the North American isolate of R. slovaca in peridomestic environments and clinical diagnosis of infection could be difficult due to the brevity and mildness of clinical signs. Further research is needed to elucidate the natural transmission cycle of R. slovaca both in Europe and North America, as well as

  13. MOLECULAR DETECTION AND CLONING FOR RICKETTSIA-LIKE BACTERIA OF MILKY HAEMOLYMPH DISEASE OF SPINY LOBSTER Panulirus spp.

    Directory of Open Access Journals (Sweden)

    Isti Koesharyani

    2017-01-01

    Full Text Available Spiny lobster (Panulirus homarus and Panulirus ornatus are important commodities for Indonesia. The aquaculture of lobster is susceptible for several diseases like parasite, fungi, bacteria, and virus. Among those diseases, milky haemolymph disease (MHD is often seen as a symptom to mass mortality occurred at lobster farms in Gerupuk Bay of Lombok. The purpose of this study was to determine the lobster diseases on cage culture in Gerupuk Bay of Lombok, West Nusa Tenggara. The study was undertaken from January to March 2015. Diseases status was determined by application of molecular plat-form, polymerase chain reaction (PCR with designation of specific primer for MHD (254F/R, 254F: 5’-CGA-GGA-CCA-GAG-ATG-GAC-CTT-3’ and 254R: 5’-GCT-CAT-TGT-CAC-CGC-CAT-TGT-3’ with PCR size product of 254 bp. and for cloned the pathogen was used TA-cloning Invitrogen for the DNA plasmid as positive control for other analysis. Several tissue samples i.e hepatopancreas, haemolymph, part of muscle hepatopancreas P. homarus and P. ornatus were taken from cage culture farms at Gerupuk Bay then preserved on 90% ethanol for further analysis by PCR and then the amplificated DNA were cloned into pCR®2.1 plasmid and transformed into competent E. coli. The result showed that almost all lobster samples from Gerupuk Bay were positive infected by MHD, as the results of PCR amplification whereas the band appeared at 254bp. Also MHD plasmid has been successfully cloned and will be used for further examination. Histopathologically in hepatopancreas infection have seen necrosis that contain numerous of rickettsia-like bacteria.

  14. Bivalve carrying capacity in coastal ecosystems

    NARCIS (Netherlands)

    Dame, R.F.; Prins, T.C.

    1998-01-01

    carrying capacity of suspension feeding bivalves in 11 coastal and estuarine ecosystems is examined. Bivalve carrying capacity is defined in terms of water mass residence time, primary production time and bivalve clearance time. Turnover times for the 11 ecosystems are compared both two and three

  15. The Concept of Carrying Capacity in Tourism

    Directory of Open Access Journals (Sweden)

    Josef Zelenka

    2014-05-01

    Full Text Available Carrying capacity is often pragmatically, theoretically as well as purely intuitively considered as a concept in the context of tourism sustainability. The carrying capacity application has the greatest potential in protected areas, in frequently visited cultural and natural attractions, and in relation to sustaining of the lifestyle of the local community and tourism destination potential in general. Despite its importance, partial applications, determination of basic theoretical principles, and specifying connection to the other theoretical concepts in tourism (particularly destination life cycle, LAC concept, visitors management, there still is a rightful opinion of some authors suggesting that there is no consistent theory of tourism carrying capacity. This theory would be the base for sophisticated practical carrying capacity applications. This paper is therefore focused on introduction of the theoretical concept of carrying capacity, which can be discussed and possibly further elaborated.

  16. Relative sensitivity of conventional and real-time PCR assays for detection of SFG Rickettsia in blood and tissue samples from laboratory animals.

    Science.gov (United States)

    Zemtsova, Galina E; Montgomery, Merrill; Levin, Michael L

    2015-01-01

    Studies on the natural transmission cycles of zoonotic pathogens and the reservoir competence of vertebrate hosts require methods for reliable diagnosis of infection in wild and laboratory animals. Several PCR-based applications have been developed for detection of infections caused by Spotted Fever group Rickettsia spp. in a variety of animal tissues. These assays are being widely used by researchers, but they differ in their sensitivity and reliability. We compared the sensitivity of five previously published conventional PCR assays and one SYBR green-based real-time PCR assay for the detection of rickettsial DNA in blood and tissue samples from Rickettsia- infected laboratory animals (n = 87). The real-time PCR, which detected rickettsial DNA in 37.9% of samples, was the most sensitive. The next best were the semi-nested ompA assay and rpoB conventional PCR, which detected as positive 18.4% and 14.9% samples respectively. Conventional assays targeting ompB, gltA and hrtA genes have been the least sensitive. Therefore, we recommend the SYBR green-based real-time PCR as a tool for the detection of rickettsial DNA in animal samples due to its higher sensitivity when compared to more traditional assays.

  17. Evidencia serológica de la presencia de Rickettsias del grupo de la fiebre manchada en la Amazonía del Perú

    Directory of Open Access Journals (Sweden)

    Moisés Sihuincha M

    2006-10-01

    Full Text Available Con el objetivo de demostrar la existencia de transmisión de Rickettsias del grupo de la fiebre manchada en la Amazonía peruana, se tomaron muestras de sangre a pacientes febriles agudos en establecimientos de salud de la ciudad de Iquitos, la ciudad más poblada de la Amazonía del Perú. Las muestras fueron procesadas mediante inmunofluorescencia indirecta para medir anticuerpos totales e IgG específica para el grupo de fiebre de las manchadas. Entre enero y julio de 2006, se obtuvieron muestras de 250 pacientes. El 37% de las muestras tuvieron títulos positivos de IgG, demostrando así haber tenido contacto con el agente, de ellas, nueve fueron clasificadas como casos agudos, en los que se descartó otras infecciones endémicas como dengue, malaria y leptospirosis. Los casos presentaron una enfermedad febril acompañada de síntomas como tos, sarpullido y hemoptisis. Cuatro casos fueron hospitalizados, dos fueron graves y uno de ellos falleció. En conclusión, existe evidencia serológica de la circulación de Rickettsias del grupo de las fiebre manchada en la Amazonía peruana, por su frecuencia y potencial gravedad debería ser tomada en cuenta como diagnóstico diferencial del síndrome febril agudo en esta región.

  18. Prevalence and clinical presentation of Rickettsia, Coxiella, Leptospira, Bartonella and chikungunya virus infections among hospital-based febrile patients from December 2008 to November 2009 in Bangladesh.

    Science.gov (United States)

    Faruque, Labib Imran; Zaman, Rashid Uz; Gurley, Emily S; Massung, Robert F; Alamgir, A S M; Galloway, Renee L; Powers, Ann M; Bai, Ying; Kosoy, Michael; Nicholson, William L; Rahman, Mahmudur; Luby, Stephen P

    2017-02-13

    We conducted a study to identify Rickettsia, Coxiella, Leptospira, Bartonella, and Chikungunya virus infections among febrile patients presenting at hospitals in Bangladesh. We collected blood samples from patients at six tertiary hospitals from December 2008 to November 2009 and performed laboratory tests at the United States Centers for Disease Control and Prevention (CDC). Out of 720 enrolled patients, 263 (37%) were infected with Rickettsia; 132 patients had immunofluorescence antibody titer >64 against spotted fever, 63 patients against scrub typhus fever and 10 patients against typhus fever. Ten patients were identified with Coxiella. We isolated Leptospira from two patients and Bartonella from one patient. Ten patients had antibodies against Chikungunya virus. The proportion of patients who died was higher with rickettsial fever (5%) compared to those without a diagnosis of rickettsial infection (2%). None of the patients were initially diagnosed with rickettsial fever. Rickettsial infections are frequent yet under-recognized cause of febrile illness in Bangladesh. Clinical guidelines should be revised so that local clinicians can diagnose rickettsial infections and provide appropriate drug treatment.

  19. Properties of information carrying waves in cosmology

    International Nuclear Information System (INIS)

    O'Shea, E.M.

    2004-01-01

    Recently we studied the effects of information carrying waves propagating through isotropic cosmologies. By information carrying we mean that the waves have an arbitrary dependence on a function. We found that the waves introduce shear and anisotropic stress into the universe. We then constructed explicit examples of pure gravity wave perturbations for which the presence of this anisotropic stress is essential and the null hypersurfaces playing the role of the histories of the wavefronts in the background space-time are shear free. Motivated by this result we now prove that these two properties are true for all information carrying waves in isotropic cosmologies

  20. Population growth and earth's human carrying capacity.

    Science.gov (United States)

    Cohen, J E

    1995-07-21

    Earth's capacity to support people is determined both by natural constraints and by human choices concerning economics, environment, culture (including values and politics), and demography. Human carrying capacity is therefore dynamic and uncertain. Human choice is not captured by ecological notions of carrying capacity that are appropriate for nonhuman populations. Simple mathematical models of the relation between human population growth and human carrying capacity can account for faster-than-exponential population growth followed by a slowing population growth rate, as observed in recent human history.

  1. Gun Carrying by High School Students in Boston, MA: Does Overestimation of Peer Gun Carrying Matter?

    Science.gov (United States)

    Hemenway, David; Vriniotis, Mary; Johnson, Renee M.; Miller, Matthew; Azrael, Deborah

    2011-01-01

    This paper investigates: (1) whether high school students overestimate gun carrying by their peers, and (2) whether those students who overestimate peer gun carrying are more likely to carry firearms. Data come from a randomly sampled survey conducted in 2008 of over 1700 high school students in Boston, MA. Over 5% of students reported carrying a…

  2. First identification of natural infection of Rickettsia rickettsii in the Rhipicephalus sanguineus tick, in the State of Rio de Janeiro Primeira identificação de infecção natural por Rickettsia rickettsii no carrapato Rhipicephalus sanguineus no Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Nathalie C. Cunha

    2009-02-01

    Full Text Available The Brazilian Spotted Fever (BSF is a zoonotic disease caused by Rickettsia rickettsii and transmitted by ticks of the genus Amblyomma, more frequently, Amblyomma cajennense. The aim of this paper was to report the first molecular detection of R. rickettsii on R. sanguineus naturally infected in Rio de Janeiro, Brazil. Ticks were collected from dogs in a rural region of Resende municipality, Rio de Janeiro State, Brazil (22º30'9.46"S, 44º42'44.29"WO, where occurred five human cases of BSF in 2006. The ticks were identified under a stereoscopic microscope and separated in pools by stages, species and sex. DNA extraction was carried out using QIAamp DNA Mini Kit (QIAGEN®. The DNA was submitted to PCR amplification using 04 set of primers: Rr190.70p/Rr190.602n (OmpA, 532bp, BG1-21/BG2-20 (OmpB, 650bp, Tz15/Tz16 (17 kDa protein-encoding gene, 246bp and RpCS.877p/RpCS.1258n (gltA, 381bp. PCR products were separated by electrophoresis on 1% agarose gels and visualized under ultraviolet light with ethidium bromide. PCR products of the expected sizes were purified by QIAquick® and sequenced by ABI PRISM®. The generated nucleotide sequences were edited with using Bioedit® software and compared with the corresponding homologous sequences available through GenBank, using Discontiguous Mega Blast (http://www.ncbi.nlm.nih.gov. It was confirmed R. rickettsii by sequencing of the material (GenBank FJ356230. The molecular characterization of R. rickettsii in the tick R. sanguineus emphasizes the role of dogs as carriers of ticks from the environment to home. Moreover, this result suggests that there is a considerable chance for active participation of R. sanguineus as one of tick species in the transmission of R. ricketsii to human being in the Brazilian territory.A Febre Maculosa Brasileira (FMB é uma zoonose causada por Rickettsia rickettsii e transmitida por carrapatos do gênero Amblyomma, mais freqüentemente pela espécie Amblyomma cajennense. Este

  3. Optimal growth trajectories with finite carrying capacity

    Science.gov (United States)

    Caravelli, F.; Sindoni, L.; Caccioli, F.; Ududec, C.

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  4. An Optical Carry Chain Fast Adder

    Directory of Open Access Journals (Sweden)

    D. Al-Dabass

    1994-12-01

    Full Text Available A significant problem in Arithmetic Unit design and particularly for systolic arrays remains the speed attainable in achieving high speed addition. The root of the problem is carry propagation and a method is presented which is relatively independent of word length. The problem is addressed by the description of a suggested radical design involving a hybrid optical and electronic approach. The method of carry chain addition through pass gates is explained and a suggested implementation utilising Fabry-Perott resonators, optical waveguides and voltage controlled couplers is described. The design is suitable for n-stage modular expansion.

  5. Parallelization of Reversible Ripple-carry Adders

    DEFF Research Database (Denmark)

    Thomsen, Michael Kirkedal; Axelsen, Holger Bock

    2009-01-01

    The design of fast arithmetic logic circuits is an important research topic for reversible and quantum computing. A special challenge in this setting is the computation of standard arithmetical functions without the generation of \\emph{garbage}. Here, we present a novel parallelization scheme......{O}(m\\cdot k)$. The underlying mechanisms of the parallelization scheme are formally proven correct. We also show designs for garbage-less reversible comparison circuits. We compare the circuit costs of the resulting ripple-block carry adder with known optimized reversible ripple-carry adders in measures...

  6. Abstraction carrying code and resource-awareness

    OpenAIRE

    Hermenegildo, Manuel V.; Albert Albiol, Elvira; López García, Pedro; Puebla Sánchez, Alvaro Germán

    2005-01-01

    Proof-Carrying Code (PCC) is a general approach to mobile code safety in which the code supplier augments the program with a certifícate (or proof). The intended benefit is that the program consumer can locally validate the certifícate w.r.t. the "untrusted" program by means of a certifícate checker—a process which should be much simpler, eíñcient, and automatic than generating the original proof. Abstraction Carrying Code (ACC) is an enabling technology for PCC in which an abstract mod...

  7. Carrying capacity: maintaining outdoor recreation quality

    Science.gov (United States)

    David W. Lime; George H. Stankey

    1971-01-01

    A discussion of (1) what is meant by the concept of recreational carrying capacity; (2) what is known about capacities in terms of both how resources and experience of visitors are affected by recreational use; and (3) what alternative procedures the administrator can use to manage both resources and visitors for capacity.

  8. Error propagation in energetic carrying capacity models

    Science.gov (United States)

    Pearse, Aaron T.; Stafford, Joshua D.

    2014-01-01

    Conservation objectives derived from carrying capacity models have been used to inform management of landscapes for wildlife populations. Energetic carrying capacity models are particularly useful in conservation planning for wildlife; these models use estimates of food abundance and energetic requirements of wildlife to target conservation actions. We provide a general method for incorporating a foraging threshold (i.e., density of food at which foraging becomes unprofitable) when estimating food availability with energetic carrying capacity models. We use a hypothetical example to describe how past methods for adjustment of foraging thresholds biased results of energetic carrying capacity models in certain instances. Adjusting foraging thresholds at the patch level of the species of interest provides results consistent with ecological foraging theory. Presentation of two case studies suggest variation in bias which, in certain instances, created large errors in conservation objectives and may have led to inefficient allocation of limited resources. Our results also illustrate how small errors or biases in application of input parameters, when extrapolated to large spatial extents, propagate errors in conservation planning and can have negative implications for target populations.

  9. Construction of expression vectors carrying mouse peroxisomal ...

    African Journals Online (AJOL)

    The aim of this study was to construct expression vectors carrying mouse peroxisomal protein gene (PEP-cDNA) in prokaryotic and mammalian expression vectors in ... pGEX6p2-PEP and pUcD3-FLAG-PEP constructed vectors were transformed into the one shot TOP10 and JM105 bacterial competent cells, respectively.

  10. Transgenic cassava lines carrying heterologous alternative oxidase ...

    African Journals Online (AJOL)

    Afuape

    2013-07-03

    Jul 3, 2013 ... Organized embryogenic callus development: In our experiment, somatic embryos were developed from leaf lobes collected from transgenic cassava lines carrying the AtAOX1a gene. Immature leaf lobes measuring about 1 to 6 mm obtained from about six weeks old in vitro derived plants were used.

  11. Magnetoacoustic waves in current-carrying plasmas

    International Nuclear Information System (INIS)

    Brennan, M.H.

    1980-04-01

    The results of theoretical and experimental investigations of the characteristics of magnetoacoustic waves in non-uniform, current-carrying plasmas are reviewed. Dissipative MHD and collisionless theories are considered. Also discussed is the use of magnetoacoustic waves in plasma diagnostics and plasma heating

  12. Microfluidic device for carrying out a reaction

    NARCIS (Netherlands)

    Iordanov, V.; Bastemeijer, J.; Bossche, A.; Sarro, P.M.

    2005-01-01

    A device for carrying out a reaction, which device comprises a wafer provided with a group of at least two wells. The wells are thermally separate from each other by means of a groove in a layer of the device, while parts separated by the groove are locally connected by bridges. In this way a device

  13. Transgenic cassava lines carrying heterologous alternative oxidase ...

    African Journals Online (AJOL)

    Messenger RNA was extracted from selected PCR-positive lines for reverse transcription-PCR analysis for gene expression. To screen positive lines for gene function, leaf lobes from two transgenic lines with a line carrying an empty vector and the wild type were subjected to somatic embryogenesis (SE), a known oxidative ...

  14. Development of Oxygen-Carrying Compounds

    Science.gov (United States)

    1942-10-16

    lth-ugh nc suggestion w:.s nude th t the oxygen in tiu compounds night be carried reversibly they c.ppeared worth investig. ting. The - llylamine...revolution every nine- teen minutes. The accompanying diagram ehovs the machine in its first form. The driv~ and Rear reduction mechanism of this

  15. Like an eagle carries its young

    Directory of Open Access Journals (Sweden)

    Hans-Georg Wünch

    2016-07-01

    Full Text Available The picture of an eagle carrying its young on its wings (Dt 32:11 is a powerful and encouraging image of trust and security in God. It is particularly relevant for Western culture, where the eagle is a prominent symbol of power and strength. In recent years, though, the translation of the Hebrew term רֶשֶׁנ as ‘eagle’ has come into question and modern exegetes claim that it is more accurately translated as ‘vulture’. But can this really be a symbol of comfort? Furthermore, do eagles (or vultures even carry their young on their wings? This article intends to shed some light on these questions. Keywords: Old Testament; Deuteronomy; Eagle; Vulture

  16. Proof-Carrying Code with Correct Compilers

    Science.gov (United States)

    Appel, Andrew W.

    2009-01-01

    In the late 1990s, proof-carrying code was able to produce machine-checkable safety proofs for machine-language programs even though (1) it was impractical to prove correctness properties of source programs and (2) it was impractical to prove correctness of compilers. But now it is practical to prove some correctness properties of source programs, and it is practical to prove correctness of optimizing compilers. We can produce more expressive proof-carrying code, that can guarantee correctness properties for machine code and not just safety. We will construct program logics for source languages, prove them sound w.r.t. the operational semantics of the input language for a proved-correct compiler, and then use these logics as a basis for proving the soundness of static analyses.

  17. Rickettsia amblyommii associado a roedores e marsupiais nativos da Estação Experimental Rafael Fernandes da UFERSA, Rio Grande do Norte

    Directory of Open Access Journals (Sweden)

    Kaliane A.R. Paiva

    Full Text Available RESUMO: O presente estudo teve como objetivo registrar a ocorrência de Rickettsia sp. em roedores e marsupiais nativos da Estação Experimental Rafael Fernandes da UFERSA, Mossoró/RN. O trabalho consistiu em uma pesquisa de campo, com roedores e marsupiais silvestres, com os dados expressos em frequência simples e porcentagem através do programa estatístico IBM SPSS (Armonk, NY: IBM Corp., versão 22.0. Coletaram-se amostras de plasma sanguíneo de marsupiais (36 e de roedores (5. Destes, 64 continham Amblyomma auricularium, 7 Amblyomma parvum e 12 Amblyomma sp. As amostras de plasma sanguíneo foram analisadas através da técnica de Reação de Imunofluorescência Indireta. Exemplares de A. auricularium e a A. parvum foram macerados e submetidos a Técnica de Reação em Cadeia da Polimerase. Das amostras de plasma testadas, 17,60% apresentaram soropositividade para Rickettsia amblyommii. Oito exemplares de A. auricularium estavam positivos para R. amblyommii na análise de fragmentos dos genes gltA (350 bp e ompA (587 pb, com 100% de similaridade com Candidatus R. amblyommii estirpe Bahia e AaPE, correspondendo a uma baixa circulação do agente dentre os vetores e hospedeiros. Esta pesquisa registra pela primeira vez a ocorrência de R. amblyommii em marsupiais Gracilinanus agilis e Monodelphis domestica pertencentes a Família Didelphidae, e roedores das Famílias Echimyidae e Cricetidae, cujas espécies foram Thrichomys sp. e Wiedomys sp., respectivamente, em Mossoró, estado do Rio Grande do Norte.

  18. Comparative genomic analysis of Rickettsia rickettsii for identification of drug and vaccine targets: tolC as a proposed candidate for case study.

    Science.gov (United States)

    Maurya, Pramod Kumar; Singh, Swati; Mani, Ashutosh

    2018-02-21

    Antibiotic resistance is increasing rapidly in pathogenic organisms, creating more complications for treatment of diseases. Rocky Mountain spotted fever (RMSF) is a neglected tropical disease in humans caused by Rickettsia rickettsii for which no effective therapeutic is available. Subtractive genomics methods facilitate the characterization of non-homologous essential proteins that could be targeted for the discovery of potential therapeutic compounds against R. rickettsii to combat RMSF. Present study followed an in-silico based methodology, involving scanning and filtering the complete proteome of Rickettsia rickettsii by using several prioritization parameters in the search of potential candidates for drug development. Further the putative targets were subjected to series of molecular dockings with ligands obtained from PDB ligand database to identify suitable potential inhibitors. The comparative genomic analysis revealed 606 non-homologous proteins and 233 essential non-homologous proteins of R. rickettsii. The metabolic pathway analysis predicted 120 proteins as putative drug targets, out of which 56 proteins were found to be associated with metabolic pathways unique to the bacteria and further subcellular localization analysis revealed that 9 proteins as potential drug targets which are secretion proteins, involved in peptidoglycan biosynthesis, folate biosynthesis and bacterial secretion system. As secretion proteins are more feasible as vaccine candidates, we have selected a most potential target i.e. tolC, an outer membrane efflux protein that belongs to type I secretion system and has major role in pathogen survival as well as MDR persistence. So for case study, we have modelled the three dimensional structure of tolC (tunnel protein). The model was further subjected to virtual screening and in-silico docking. The study identified three potential inhibitors having PDB Id 19V, 6Q8 and 39H. Further we have suggested that the above study would be most

  19. Development of pellet chain for charge carrying

    International Nuclear Information System (INIS)

    Chung, K.H.; Ko, S.K.; Choi, B.H.; Hong, J.H.

    1988-01-01

    This paper reports on the development of pellet chain and charge induction components which are used for charge carrying in electrostatic accelerators. It has very simple structure, and its fabrication cost is low. As the results of the test, first, mechanical vibration is reduced for operation and torsional stress due to belt twisting is removed completely. Second, after insertion of the material with high dielectric constant in charge induction assembly, the capacitance between pellets and inductor is increased. Third, for measurement of the life time of chain, it is continuously on the operation

  20. Cryptococcus neoformans carried by Odontomachus bauri ants

    Directory of Open Access Journals (Sweden)

    Mariana Santos de Jesus

    2012-06-01

    Full Text Available Cryptococcus neoformans is the most common causative agent of cryptococcosis worldwide. Although this fungus has been isolated from a variety of organic substrates, several studies suggest that hollow trees constitute an important natural niche for C. neoformans. A previously surveyed hollow of a living pink shower tree (Cassia grandis positive for C. neoformans in the city of Rio de Janeiro, Brazil, was chosen for further investigation. Odontomachus bauri ants (trap-jaw ants found inside the hollow were collected for evaluation as possible carriers of Cryptococcus spp. Two out of 10 ants were found to carry phenoloxidase-positive colonies identified as C. neoformans molecular types VNI and VNII. The ants may have acted as a mechanical vector of C. neoformans and possibly contributed to the dispersal of the fungi from one substrate to another. To the best of our knowledge, this is the first report on the association of C. neoformans with ants of the genus Odontomachus.

  1. Azobenzene derivatives carrying a nitroxide radical.

    Science.gov (United States)

    Nakatsuji, Shin'ichi; Fujino, Masahiro; Hasegawa, Satoko; Akutsu, Hiroki; Yamada, Jun-ichi; Gurman, Vladimir S; Kh Vorobiev, Andrey

    2007-03-16

    Several trans-azobenzene derivatives carrying a nitroxide (aminoxyl) radical (2a, 6a-12a) were prepared, and their photoisomerization reactions to the corresponding cis-isomers were investigated. Although no fruitful results could be obtained for the photoisomerizations of the derivatives with para-subsituents (9a-12a), the unsubstututed derivatives at the para-position (2a, 6a, 7a, 8a) were found to show photoisomerizations by irradiation to give the corresponding cis-isomers (2b, 6b, 7b, 8b), being isolated as relatively stable solid materials, and the change of the intermolecular magnetic interactions was apparently observed by the structural change for each photochromic couple.

  2. DETECTING VESSELS CARRYING MIGRANTS USING MACHINE LEARNING

    Directory of Open Access Journals (Sweden)

    A. Sfyridis

    2017-10-01

    Full Text Available Political instability, conflicts and inequalities result into significant flows of people worldwide, moving to different countries in search of a better life, safety or to be reunited with their families. Irregular crossings into Europe via sea routes, despite not being new, have recently increased together with the loss of lives of people in the attempt to reach EU shores. This highlights the need to find ways to improve the understanding of what is happening at sea. This paper, intends to expand the knowledge available on practices among smugglers and contribute to early warning and maritime situational awareness. By identifying smuggling techniques and based on anomaly detection methods, behaviours of interest are modelled and one class support vector machines are used to classify unlabelled data and detect potential smuggling vessels. Nine vessels are identified as potentially carrying irregular migrants and refugees. Though, further inspection of the results highlights possible misclassifications caused by data gaps and limited knowledge on smuggling tactics. Accepted classifications are considered subject to further investigation by the authorities.

  3. Detecting Vessels Carrying Migrants Using Machine Learning

    Science.gov (United States)

    Sfyridis, A.; Cheng, T.; Vespe, M.

    2017-10-01

    Political instability, conflicts and inequalities result into significant flows of people worldwide, moving to different countries in search of a better life, safety or to be reunited with their families. Irregular crossings into Europe via sea routes, despite not being new, have recently increased together with the loss of lives of people in the attempt to reach EU shores. This highlights the need to find ways to improve the understanding of what is happening at sea. This paper, intends to expand the knowledge available on practices among smugglers and contribute to early warning and maritime situational awareness. By identifying smuggling techniques and based on anomaly detection methods, behaviours of interest are modelled and one class support vector machines are used to classify unlabelled data and detect potential smuggling vessels. Nine vessels are identified as potentially carrying irregular migrants and refugees. Though, further inspection of the results highlights possible misclassifications caused by data gaps and limited knowledge on smuggling tactics. Accepted classifications are considered subject to further investigation by the authorities.

  4. Voltage-carrying states in superconducting microstrips

    International Nuclear Information System (INIS)

    Stuivinga, M.E.C.

    1983-01-01

    When the critical current is exceeded in a superconducting microstrip, voltage-carrying states with a resistance significantly below the normal state resistance can occur. Phase-slip centers (PSC) appear at about the critical temperature. These are successive local voltage units which manifest themselves as strip-like increments in voltage in the I-V characteristic. For temperatures off the critical temperature the PSC regime degenerates into a region of normal material, a so-called hot spot. These two phenomena, PSC and hot spots, form the subject of this thesis. To gain a better understanding of the phase-slip center process, an experiment was designed to measure local values of the quasi-particle and pair potential. The results of local potential and gap measurements at a PSC in aluminium are presented and discussed. Special attention is paid to pair-breaking interactions which can shorten the relaxation time. A non-linear differential equation is derived which describes the development of a PSC into a normal hot spot under the influence of Joule heating. It incorporates the temperature rise due to the dissipative processes occurring in the charge imbalance tails. Numerical solutions are presented for a set of parameters, including those for aluminium and tin. Subsequently, they are compared with experiments. (Auth.)

  5. Biofouling control using microparticles carrying a biocide.

    Science.gov (United States)

    Ferreira, C; Rosmaninho, R; Simoes, M; Pereira, M C; Bastos, M M S M; Nunes, O C; Coelho, M; Melo, L F

    2010-01-01

    This study presents a new technological approach to minimize the use of antimicrobial (AMB) agents and their deleterious effects, based on the principle of drug-delivery systems whereby the AMB chemicals are transported on microparticles. The efficacy of microparticles carrying the quaternary ammonium compound (QAC), benzyldimethyldodecyl ammonium chloride (BDMDAC), was assessed against Pseudomonas fluorescens in both the planktonic and the biofilm state. The microparticles were prepared using a layer-by-layer (LBL) self-assembly technique. Oppositely charged molecules of polyethyleneimine (PEI), sodium polystyrene sulfonate (PSS), and BDMDAC were assembled on polystyrene (PS) cores. BDMDAC-coated particles were observed by CryoSEM and their composition analyzed by X-ray microanalysis. Zeta potential measurements indicated that changes in surface charge were compatible with a BDMDAC/particle interaction. This biocidal carrier structure had significant stability, verified by the release of only 15% of the BDMDAC when immersed in water for 18 months. Biocidal carrier activity was evaluated by determining the survival ratio of P. fluorescens planktonic and biofilm cells after different exposure periods to BDMDAC-coated particles. Tests with biofilm cells were also performed with the free QAC. An efficient AMB effect (minimum bactericidal concentration) against suspended cells was found for a concentration of 9.2 mg l(-1) of BDMDAC on coated particles after incubation for 30 min and 6.5 mg l(-1) of BDMDAC on coated particles after 60 min. Exposure of biofilms to PS-PEI/PSS/BDMDAC (0.87 mg l(-1)) resulted in a decrease in viability of 60.5% and 66.5% of the total biofilm population for 30 and 60 min exposure times, respectively. Exposure for 60 min to 6.33 mg l(-1) and 11.75 mg l(-1) of BDMDAC in PS-PEI/PSS/BDMDAC particles promoted inactivation of 80.6% and 87.2% of the total population, respectively. The AMB effects obtained with the application of free BDMDAC were

  6. Serological survey of Rickettsia sp. in horses and dogs in an non-endemic area in Brazil Identificação sorológica de Rickettsia sp. em equinos e cães de área não endêmica no Brasil

    Directory of Open Access Journals (Sweden)

    Fernanda Gonçalves Batista

    2010-12-01

    Full Text Available Brazilian Spotted Fever (BSF is a lethal rickettsiosis in humans caused by the bacteria Rickettsia rickettsii, and is endemic in some areas of Brazil. Horses and dogs are part of the disease's life cycle and they may also serve as sentinel animals in epidemiological studies. The first human BSF case in the State of Paraná was reported in 2005. The present study was conducted in the municipality of Almirante Tamandaré, where no previous case of BSF was reported. Serum samples were collected from 71 horses and 20 dogs from nine properties in the area. Ticks were also collected from these animals. All farmers completed a questionnaire about their knowledge of BSF and animal health management. Serum samples were analyzed by indirect immunofluorescent-antibody assay (IFA using R. rickettsii and R. parkeri as antigens. Ticks were analyzed by PCR for Rickettsia sp., and all of them were PCR-negative. Six horses (8.45% and 4 dogs (20% were identified as seropositive. Farmers were not aware of the correlation between the presence of ticks and risk of BSF. Although a non-endemic area, Almirante Tamandaré is a vulnerable environment for BSF and effective tick control measures are required.A Febre Maculosa Brasileira (FMB é uma riquetsiose letal para humanos, causada pela bactéria Rickettsia rickettsii, e é endêmica em algumas regiões brasileiras. Equinos e cães podem participar do ciclo da doença e podem também servir como sentinelas em estudos epidemiológicos. O primeiro caso humano relatado no Estado do Paraná ocorreu em 2005. O presente estudo foi realizado no município de Almirante Tamandaré, região onde não há relatos de casos de FMB. Foram coletadas amostras de sangue de 71 cavalos e 20 cães em nove propriedades rurais na região. Carrapatos também foram colhidos dos animais. Todos os proprietários responderam a um questionário sobre o manejo sanitário dos animais e o conhecimento a respeito da FMB. As amostras de soro foram

  7. Ultrastructural description of new Rickettsia-like organisms in the commercial abalone Haliotis tuberculata (Gastropoda: Haliotidae) from the NW of Spain.

    Science.gov (United States)

    Azevedo, Carlos; Conchas, Ramón F; Tajdari, Jessica; Montes, Jaime

    2006-08-30

    Rickettsia-like organisms (RLOs) were found in the commercially farmed abalone Haliotis tuberculata in the northwestern region of the Atlantic Coast of Spain and are described from light and transmission electron microscopy observations. The RLOs measured approximately 1.6 x 0.9 microm and were found in intracytoplasmic, spherical to ellipsoidal vacuoles (up to 8 microm) in the epithelial cells of the digestive diverticulae. The morphological ultrastructure of these organisms was typically prokaryotic, including a plasmalemma and a thin Gram-negative type cell wall. Several ultrastructural changes were observed in the epithelial cells of the host containing the RLOs. The nuclei became pycnotic and several basophilic dense inclusions appeared in the cytoplasm. In addition, the host cell appeared lysed and was ruptured in advanced stages of infection. It was impossible to ascertain whether the RLOs are responsible for this disease, as a haplosporidian infection was also present. We can only conclude that the presence of RLOs simultaneously with a haplosporidian parasite may contribute to the mortality of the abalone host.

  8. Comparative Evaluation of Infected and Noninfected Amblyomma triste Ticks with Rickettsia parkeri, the Agent of an Emerging Rickettsiosis in the New World

    Directory of Open Access Journals (Sweden)

    F. A. Nieri-Bastos

    2013-01-01

    Full Text Available The distribution of Rickettsia parkeri in South America has been associated with Amblyomma triste ticks. The present study evaluated under laboratory conditions two colonies of A. triste: one started from engorged females that were naturally infected by R. parkeri (designated as infected group; the other started from noninfected females (designated as control group. Both colonies were reared in parallel for five consecutive generations. Tick-naïve domestic rabbits were used for feeding of each tick stage and generation. R. parkeri was preserved by transstadial maintenance and transovarial transmission in A. triste ticks for five consecutive generations, because all tested larvae, nymphs, and adults from the infected group were shown by PCR to contain rickettsial DNA. All rabbits infested by larvae, nymphs, and adults from the infected group seroconverted, indicating that these tick stages were all vector competent for R. parkeri. Expressive differences in mortality rates were observed between engorged nymphs from the infected and control groups, as indicated by 65.9% and 92.4% molting success, respectively. Our results indicate that A. triste can act as a natural reservoir for R. parkeri. However, due to deleterious effect caused by R. parkeri on engorged nymphs, amplifier vertebrate hosts might be necessary for natural long-term maintenance of R. parkeri in A. triste.

  9. Bacterial tick-borne diseases caused by Bartonella spp., Borrelia burgdorferi sensu lato, Coxiella burnetii, and Rickettsia spp. among patients with cataract surgery.

    Science.gov (United States)

    Chmielewski, Tomasz; Brydak-Godowska, Joanna; Fiecek, Beata; Rorot, Urszula; Sędrowicz, Elżbieta; Werenowska, Małgorzata; Kopacz, Dorota; Hevelke, Agata; Michniewicz, Magdalena; Kęcik, Dariusz; Tylewska-Wierzbanowska, Stanisława

    2014-06-05

    Clinical data have shown that tick-borne diseases caused by Borrelia burgdorferi sensu lato, Bartonella spp., Coxiella burnetii, and Rickettsia spp. can affect the central nervous system, including the eye. The aim of this study was to establish a relationship between the incidence of cataract and evidence of bacterial infections transmitted by ticks. Fluid with lenticular masses from inside of the eye and blood from 109 patients were tested by PCR and sequencing. Sera from patients and the control group were subjected to serological tests to search specific antibodies to the bacteria. Microbiological analysis revealed the presence of Bartonella sp. DNA in intraoperative specimens from the eye in 1.8% of patients. Serological studies have shown that infections caused by B. burgdorferi sensu lato and Bartonella sp. were detected in 34.8% and 4.6% of patients with cataract surgery, respectively. Presence of DNA of yet uncultured and undescribed species of Bartonella in eye liquid indicates past infection with this pathogen. Specific antibodies to B. burgdorferi sensu lato and Bartonella sp. are detected more frequently in patients with cataract compared to the control group. This could indicate a possible role of these organisms in the pathological processes within the eyeball, leading to changes in the lens. Further studies are needed to identify Bartonella species, as well as to recognize the infectious mechanisms involved in cataract development.

  10. Canine vector-borne pathogens in semi-domesticated dogs residing in northern Cambodia.

    Science.gov (United States)

    Inpankaew, Tawin; Hii, Sze Fui; Chimnoi, Wissanuwat; Traub, Rebecca J

    2016-05-10

    In Southeast Asia, the canine vector-borne pathogens Babesia spp., Ehrlichia canis, Anaplasma platys, Hepatozoon canis, haemotropic mycoplasmas and Dirofilaria immitis cause significant morbidity and mortality in dogs. Moreover, dogs have also been implicated as natural reservoirs for Rickettsia felis, the agent of flea-borne spotted fever, increasingly implicated as a cause of undifferentiated fever in humans in Southeast Asia. The objective of this study was to determine the prevalence and diversity of canine vector-borne pathogens in 101 semi-domesticated dogs from rural Cambodia using molecular diagnostic techniques. The most common canine vector-borne pathogens found infecting dogs in this study were Babesia vogeli (32.7 %) followed by Ehrlichia canis (21.8 %), Dirofilaria immitis (15.8 %), Hepatozoon canis (10.9 %), Mycoplasma haemocanis (9.9 %) and "Candidatus Mycoplasma haematoparvum" (2.9 %). A high level of co-infection with CVBD agents (23.8 %) was present, most commonly B. vogeli and E. canis. Naturally occurring R. felis infection was also detected in 10.9 % of dogs in support of their role as a natural mammalian reservoir for flea-borne spotted fever in humans. This study reports for the first time, the prevalence and diversity of CVBD pathogens in dogs in Cambodia. In total, five species of CVBD pathogens were found infecting semi-domesticated dogs and many were co-infected with two or more pathogens. This study supports the role of dogs as natural mammalian reservoirs for R. felis, the agent of flea-borne spotted fever in humans.

  11. The Distinct Transcriptional Response of the Midgut of Amblyomma sculptum and Amblyomma aureolatum Ticks to Rickettsia rickettsii Correlates to Their Differences in Susceptibility to Infection

    Directory of Open Access Journals (Sweden)

    Andréa C. Fogaça

    2017-04-01

    Full Text Available Rickettsia rickettsii is a tick-borne obligate intracellular bacterium that causes Rocky Mountain Spotted Fever (RMSF. In Brazil, two species of ticks in the genus Amblyomma, A. sculptum and A. aureolatum, are incriminated as vectors of this bacterium. Importantly, these two species present remarkable differences in susceptibility to R. rickettsii infection, where A. aureolatum is more susceptible than A. sculptum. In the current study, A. aureolatum and A. sculptum ticks were fed on suitable hosts previously inoculated with R. rickettsii, mimicking a natural infection. As control, ticks were fed on non-infected animals. Both midgut and salivary glands of all positively infected ticks were colonized by R. rickettsii. We did not observe ticks with infection restricted to midgut, suggesting that important factors for controlling rickettsial colonization were produced in this organ. In order to identify such factors, the total RNA extracted from the midgut (MG was submitted to next generation RNA sequencing (RNA-seq. The majority of the coding sequences (CDSs of A. sculptum differentially expressed by infection were upregulated, whereas most of modulated CDSs of A. aureolatum were downregulated. The functional categories that comprise upregulated CDSs of A. sculptum, for instance, metabolism, signal transduction, protein modification, extracellular matrix, and immunity also include CDSs of A. aureolatum that were downregulated by infection. This is the first study that reports the effects of an experimental infection with the highly virulent R. rickettsii on the gene expression of two natural tick vectors. The distinct transcriptional profiles of MG of A. sculptum and A. aureolatum upon infection stimulus strongly suggest that molecular factors in this organ are responsible for delineating the susceptibility to R. rickettsii. Functional studies to determine the role played by proteins encoded by differentially expressed CDSs in the acquisition of R

  12. Serosurvey of Rickettsia spp. in dogs and humans from an endemic area for Brazilian spotted fever in the State of São Paulo, Brazil Sorologia para Rickettsia spp. em cães e humanos de uma área endêmica para febre maculosa brasileira no Estado de São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Adriano Pinter

    2008-02-01

    Full Text Available The present study provides a rickettsial serosurvey in 25 dogs and 35 humans in an endemic area for Brazilian spotted fever in the State of São Paulo, where the tick Amblyomma aureolatum is the main vector. Testing canine and human sera by indirect immunofluorescence against four Rickettsia antigens (R. rickettsii, R. parkeri, R. felis and R. bellii showed that 16 (64% of canine sera and 1 (2.8% of human sera reacted to at least one of these rickettsial antigens with titers ³ 64. Seven canine sera and the single reactive human serum showed titers to R. rickettsii at least four times those of any of the other three antigens. The antibody titers in these 7 animals and 1 human were attributed to stimulation by R. rickettsii infection. No positive canine or human serum was attributed to stimulation by R. parkeri, R. felis, or R. bellii. Our serological results showed that dogs are important sentinels for the presence of R. rickettsii in areas where the tick A. aureolatum is the main vector of Brazilian spotted fever.Este estudo avaliou a ocorrência de anticorpos anti-Rickettsia em 25 cães e 35 humanos, em uma área endêmica para a febre maculosa brasileira no Estado de São Paulo, onde o principal vetor é o carrapato Amblyomma aureolatum. Soros dos cães e humanos foram testados pela técnica de imunofluorescência indireta contra quatro antígenos de riquétsias (R. rickettsii, R. parkeri, R. felis, R. bellii, mostrando que soros de 16 (64% cães e 1 (2,8% humano reagiram com títulos ³ 64 para pelo menos um dos antígenos de riquétsias. Sete soros caninos e o único soro humano reativo demonstraram títulos para R. rickettsii no mínimo quatro vezes maior do que aqueles para os outros antígenos de riquétsias. Os títulos de anticorpos nesses cães e um humano foram considerados homólogos a R. rickettsii, enquanto que nenhum soro de cão ou humano foi considerado reativamente homólogo para R. parkeri, R. felis ou R. bellii. Os

  13. Predicting stretcher carriage: Investigating variations in bilateral carry tests.

    Science.gov (United States)

    Beck, Ben; Middleton, Kane J; Carstairs, Greg L; Billing, Daniel C; Caldwell, Joanne N

    2016-07-01

    Carrying a casualty on a stretcher is a critical task within military and emergency service occupations. This study evaluated the impact of manipulating carry speed and the object type in bilateral carries on the ability to predict performance and reflect the physical and physiological requirements of a unilateral stretcher carry. We demonstrated that three task-related predictive tests; a jerry can carry performed at 4.5 km h(-1)or 5.0 km h(-1) and a kettle-bell carry performed at 5.0 km h(-1) were strongly predictive of the physical and physiological demands of an individual participating as part of a four-person stretcher carry team. Therefore, bilateral predictive assessments have the utility for predicting the suitability of employees to effectively and safely conduct a four-person unilateral stretcher carry. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  14. Estimation and Determination of Carrying Capacity in Loblolly Pine

    OpenAIRE

    Yang, Sheng-I

    2016-01-01

    Stand carrying capacity is the maximum size of population for a species under given environmental conditions. Site resources limit the maximum volume or biomass that can be sustained in forest stands. This study was aimed at estimating and determining the carrying capacity in loblolly pine. Maximum stand basal area (BA) that can be sustained over a long period of time can be regarded as a measure of carrying capacity. To quantify and project stand BA carrying capacity, one approach is to use ...

  15. 46 CFR 111.105-35 - Vessels carrying coal.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Vessels carrying coal. 111.105-35 Section 111.105-35...-GENERAL REQUIREMENTS Hazardous Locations § 111.105-35 Vessels carrying coal. (a) The following are Class II, Division 1, (Zone 10 or Z) locations on a vessel that carries coal: (1) The interior of each coal...

  16. Training to Increase Safe Tray Carrying Among Cocktail Servers

    OpenAIRE

    Scherrer, Megan D; Wilder, David A

    2008-01-01

    We evaluated the effects of training on proper carrying techniques among 3 cocktail servers to increase safe tray carrying on the job and reduce participants' risk of developing musculoskeletal disorders. As participants delivered drinks to their tables, their finger, arm, and neck positions were observed and recorded. Each participant received individual safety training that focused on proper carrying positions and techniques after baseline data were collected. A multiple baseline design acr...

  17. Organization and carrying out the triathlon competitions in Ukraine

    Directory of Open Access Journals (Sweden)

    Volodymyr Vodlozerov

    2016-02-01

    Full Text Available Purpose: the aim is analyzing of system of organization and carrying out the triathlon competitions in Ukraine in accordance with rules of triathlon international federation. Material & Methods: comparative analysis of process of organization and carrying out the triathlon competitions in the world and Ukraine was carried out on basis of specialist literature studying, normative base of sports organizations (triathlon federation. Results: inconsistencies were identified in competitions carried out in cold season, particularity of triathlon that intends overcoming the combined distance without time durations between stages. Conclusions: recommendation in eliminate inconsistencies that affect to performance of triathlon competitions in Ukraine was suggested.

  18. The Population Growth and Carrying Capacity in Semarang City

    Science.gov (United States)

    Hariyanto; Hadi, Sudharto P.; Buchori, Imam

    2018-02-01

    Population growth and development of city activities take some lands to carry them. As a result, land use competition happens among persons, society or sector. Land necessity for settlement, industry, or sector has taken over farm land, therefore farm land has been converted intensively and massively. Chronologically, population growth will cause land necessity increase. Unproductive land, especially farm land will be converted. Furthermore, farm land conversion will cause carrying capacity change. Carrying capacity has certain bio capacity. With the population growth, it will increase resource consumption; on the other side, farm land conversion will decrease carrying capacity. The objective of the study is to know about the influence of population growth towards carrying capacity (bio capacity) in Semarang city. Land consumption per capita is indeed influenced by city population, the higher the population is, the lower the land consumption per capita. With the population growth, it will influence carrying capacity. Carrying capacity here is the ratio of area to population. Analytical descriptive method is applied in the study with all sub-districts in Semarang city as the analysis unit. Population here is sub-district area and population per sub-district in Semarang city. Population growth data period is from 2000 until 2015. Main variables of the study are area per sub-district, population, population growth, carrying capacity. Result of the study shows significant influence of carrying capacity decrease, especially some outskirts in Semarang city. This condition happens because the outskirts in Semarang city tend to have dense population growth. Range of carrying capacity in Semarang city is from 0,007 to 0,117 of 0 to 1. Almost all sub-districts in Semarang city show miserable condition, except Mijen and Tugu. The conclusion of the study is that population will decrease carrying capacity. Therefore, the government should control population growth by paying

  19. Hand-carried echocardiography by hospitalists: a randomized trial.

    Science.gov (United States)

    Lucas, Brian P; Candotti, Carolina; Margeta, Bosko; Mba, Benjamin; Kumapley, Rudolf; Asmar, Abdo; Franco-Sadud, Ricardo; Baru, Joshua; Acob, Christine; Borkowsky, Shane; Evans, Arthur T

    2011-08-01

    Hospitalists can use hand-carried echocardiography for accurate point-of-care information, but patient outcome data for its application are sparse. We performed an unblinded, parallel-group randomized trial between July 2008 and March 2009 at one teaching hospital in Chicago, Illinois. We randomly assigned adult general medicine inpatients referred for standard echocardiography with indications investigatable by hand-carried echocardiography to care guided by hand-carried echocardiography or usual care. The main outcome measure was length of stay on the referring hospitalist's service. Secondary outcomes included a before-after analysis of reported changes in management due to hand-carried echocardiography and the diagnostic accuracy of hand-carried echocardiography. The difference in length of stay between 226 participants randomized to care guided by hand-carried echocardiography (geometric mean 46.1 hours, interquartile range 29.0-70.9 hours) and 227 participants randomized to usual care (46.9 hours, interquartile range 34.1-68.3 hours) corresponded to a 1.7% reduction in length of stay that was not statistically significant (95% confidence interval, -12.1 to 9.8%). In post hoc subgroup analyses, care guided by hand-carried echocardiography reduced length of stay in participants who were referred for heart failure (P=.0008). Among participants who underwent both hand-carried and standard echocardiography, hospitalists changed management due to hand-carried echocardiography in 37%. Despite the favorable diagnostic accuracy of hand-carried echocardiography, most changes to the timing of hospital discharge occurred after standard echocardiography. Hospitalist care guided by hand-carried echocardiography for unselected general medicine patients does not meaningfully affect length of stay. Whether or not it affects care quality remains unstudied. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. 25 CFR 23.51 - Grant carry-over authority.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Grant carry-over authority. 23.51 Section 23.51 Indians... Uniform Grant Administration Provisions and Requirements § 23.51 Grant carry-over authority. Unless... two years beyond the initial grant funding period and must be utilized only for the intent, purpose...

  1. 46 CFR 98.30-3 - Vessels carrying MPTs.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Vessels carrying MPTs. 98.30-3 Section 98.30-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL... Vessels carrying MPTs. Each MPT on a vessel to which this part applies must bear, on a metal or other...

  2. 46 CFR 111.105-45 - Vessels carrying agricultural products.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Vessels carrying agricultural products. 111.105-45... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Hazardous Locations § 111.105-45 Vessels carrying agricultural products. (a) The following areas are Class II, Division 1, (Zone 10 or Z) locations on vessels...

  3. Optimising the allocation of groundwater carrying capacity in a data ...

    African Journals Online (AJOL)

    An analysis model of groundwater carrying capacity was then established and is solved with the Lagrange multiplier method. A case study of groundwater resource carrying capacity in 2010 and 2015 in the Yaoba Oasis irrigation district, Alxa Left Prefecture, Inner Mongolia Autonomous Region, China, was performed.

  4. Ecological Carrying Capacity of Saanane Island Proposed National ...

    African Journals Online (AJOL)

    The study on ecological carrying capacity of Saanane Island aimed at assessing stocking capacity of the island to provide guidance to the introduction of animals to enhance its ecological value and tourism potential. To evaluate the ecological carrying capacity of the Island, wet and dry season data were collected in 2014 ...

  5. [Fitness, carrying capacity and competition in an ecosystem].

    Science.gov (United States)

    Wedekind, J; Wöhrmann, K

    1975-01-01

    In this paper a model is introduced in which fitness, carrying capacity and competition are considered. Thereby as well genetic as ecological parameters were assumed to become active. It results from the investigations that: 1. Competition may compensate the influence of genotypic fitness. 2. The carrying capacity has a more important influence on the construction of a population than the genotypic fitness. 3. As well competition as carrying capacity are parameters which do influence not only the size of the populations but also the genotypic construction of the populations. Therefore for a description of populations it is necessary to take into account a polyfactorial system with genotypic fitness, carrying capacity and competition. The model proposed has been compared with those described in the literature. The importance of population fitness and by it the genetic load has been discussed considering ecological parameters such as competition and carrying capacity.

  6. The flexible application of carrying capacity in ecology

    Directory of Open Access Journals (Sweden)

    Eric J. Chapman

    2018-01-01

    Full Text Available Carrying capacity encompasses a broad collection of approaches used to better understand biotic interactions in ecosystems and is often applied with no explicit regard to its historical origin. In this paper, we reviewed the primary literature to examine how carrying capacity is applied in ecology. We focused our review on ecosystem studies—studies that frame their results at the ecosystem level—published after the 1950s and highlight emerging trends of this concept. We found that while carrying capacity offers some underlying commonalities, a wide range of definitions and approaches hinders a unified framework to better understand biotic ecosystem interactions. Not surprisingly, these studies most often use K—the number of individuals that the environment “can support” in a given area—to define carrying capacity, despite considerable ambiguity and uncertainty in this approach. Furthermore, the studies that we reviewed spanned several levels of ecological organization: molecules to communities and up to landscapes. To add further complexity, it is not clear whether carrying capacity was intended as a dynamic concept subject to temporal variability as it was often applied in the reviewed studies. We found that carrying capacity is most often applied to studies in conservation biology, rangeland and wildlife management, aquaculture, and fisheries biology. We explore ecosystem level responses to implications of “carrying capacity” overshoot and discuss proposed mechanisms that govern ecosystem carrying capacity. We discuss the usefulness of the concept and end with suggestions to improve carrying capacity's general application in ecosystem studies. Keywords: Carrying capacity, Conservation biology, Ecosystems, Ecosystem management, Natural resources

  7. US Public Opinion on Carrying Firearms in Public Places.

    Science.gov (United States)

    Wolfson, Julia A; Teret, Stephen P; Azrael, Deborah; Miller, Matthew

    2017-06-01

    To estimate US public opinion, overall and by gun ownership status, about the public places where legal gun owners should be allowed to carry firearms. We fielded an online survey among 3949 adults, including an oversample of gun owners and veterans, in April 2015. We used cross-tabulations with survey weights to generate nationally representative estimates. Fewer than 1 in 3 US adults supported gun carrying in any of the specified venues. Support for carrying in public was consistently higher among gun owners than among non-gun owners. Overall, support for carrying in public was lowest for schools (19%; 95% confidence interval [CI] = 16.7, 21.1), bars (18%; 95% CI = 15.9, 20.6), and sports stadiums (17%; 95% CI = 15.0, 19.5). Most Americans, including most gun owners, support restricting public places legal gun owners can carry firearms. These views contrast sharply with the current trend in state legislatures of expanding where, how, and by whom guns can be carried in public. Recent state laws and proposed federal legislation that would force states to honor out-of-state concealed carry permits are out of step with American public opinion.

  8. Correlates of gun-carrying among adolescents in south Louisiana.

    Science.gov (United States)

    McNabb, S J; Farley, T A; Powell, K E; Rolka, H R; Horan, J M

    1996-01-01

    In the majority of episodes of fatal interpersonal violence, the weapon used is a firearm. Amid frequent reports of youths carrying weapons, including firearms, we conducted a case-control study to identify risk factors for being charged with gun-carrying and gun-carrying, per se, among adolescents in Jefferson Parish, Louisiana. Cases were defined as incidents of gun-carrying among adolescents juvenile court from January 1, 1992, through April 15, 1993. For each case, we randomly drew three age-, gender-, and school-matched control subjects from the enrollment rosters of the Jefferson Parish public schools and administered a questionnaire. The data set comprised 38 case subjects and 103 matched control subjects. Thirty (29%) control subjects reported gun-carrying. Both case subjects and gun-carrying control subjects reported self-defense (40%) as the main reason for gun-carrying. Most case subjects (25 [66%]) were African Americans, but only 8 (27%) gun-carrying and 27 (37%) non-gun-carrying control subjects were African Americans. Case subjects were significantly more likely than gun-carrying control subjects to report being African American (odds ratio [OR] = 5.3, 95% confidence intervals [CI] = 1.6, 17.5). In crude analyses, case subjects were more likely than non-gun-carrying control subjects to report adult-male unemployment among households with adult men, to foresee a likelihood to be shot in school, to have seen a shooting, to use marijuana, to watch television > 6 hours per day, and to be African American. After the effect estimates were adjusted in conditional logistic regression modeling, case subjects were more likely than non-gun-carrying control subjects to report adult-male unemployment among households with adult men, using marijuana, and watching television > 6 hours per day (OR = 8.6, 95% CI = 1.2, 61,2; OR = 11.7, 95% CI = 2, 70.2; and OR = 6.5, 95% CI = 0.8, 51.9, respectively). Gun-carrying control subjects were significantly more likely than

  9. Estimating the recreational carrying capacity of a lowland river section.

    Science.gov (United States)

    Lorenz, Stefan; Pusch, Martin T

    2012-01-01

    Recreational boating represents a major human use of inland waters in many regions. However, boating tourism may affect the ecological integrity of surface waters in multiple ways. In particular, surface waves produced by boating may disturb freshwater invertebrates, such as interrupting the filtration activity of benthic mussels. As mussels may significantly contribute to self-purification, disturbance may have crucial impacts on water quality, and thus on water tourism. In this paper we calculate the carrying capacity of a river section for sustainable boating tourism based on the preservation of water quality. This approach is complemented by spatial and social approaches for carrying capacity estimates. The ecological carrying capacity significantly decreases with lower water levels during summer. Hence, the analysis of variables that influence the river's carrying capacity allows the formation of recommendations for management measures that integrate social, touristic and ecological aspects.

  10. Hand Sanitizers Carry Unproven Claims to Prevent MRSA Infections

    Science.gov (United States)

    ... For Consumers Home For Consumers Consumer Updates Hand Sanitizers Carry Unproven Claims to Prevent MRSA Infections Share ... Flickr. Subscribe: FDA Consumer Health Information Some hand sanitizers and antiseptic products come with claims that they ...

  11. Optimising the allocation of groundwater carrying capacity in a data ...

    African Journals Online (AJOL)

    2009-08-26

    scarce region, Oasis irrigation district. Introduction. The concept of carrying ... a united definition of WRCC. Though different researchers .... data and the mining of useful information implied in the data, a new evaluation criterion of ...

  12. 46 CFR 122.340 - Vessels carrying vehicles.

    Science.gov (United States)

    2010-10-01

    ... vehicles freely in the event of fire or other disaster. The decks, where necessary, must be distinctly... smoking or carrying of lighted or smoldering pipes, cigars, cigarettes, or similar items in the deck area...

  13. 46 CFR 185.340 - Vessels carrying vehicles.

    Science.gov (United States)

    2010-10-01

    ... and away from the vehicles freely in the event of fire or other disaster. The decks, where necessary... precautions to prevent smoking or carrying of lighted or smoldering pipes, cigars, cigarettes, or similar...

  14. Foreign exchange predictability and the carry trade: a decomposition approach

    Czech Academy of Sciences Publication Activity Database

    Anatolyev, Stanislav; Gospodinov, N.; Jamali, I.; Liu, X.

    2017-01-01

    Roč. 42, June (2017), s. 199-211 ISSN 0927-5398 Institutional support: RVO:67985998 Keywords : exchange rate forecasting * carry trade * return decomposition Subject RIV: AH - Economics OBOR OECD: Finance Impact factor: 0.979, year: 2016

  15. Regression equations for circular CFST columns carrying capacity evaluation

    Directory of Open Access Journals (Sweden)

    Vatulia Glib

    2017-01-01

    Full Text Available Within the last decades, a considerable amount of experimental studies have been carried out by numerous researchers across the world with the purpose to study the carrying capacity of concrete-filled steel tubular (CFST columns and evaluation of their stressed-strained state. The array of the obtained results have allowed designing a mathematical model to determine the maximum carrying capacity value of such constructions using the methods of mathematical statistics. The authors obtained three types of regression equations for short and long circular CFST columns with different geometrical and physical properties under axial compression. Statistical quality of the obtained models was verified by both regression equation quality in general and statistical significance of the equation parameters. The comparison of the obtained carrying capacity values with the results calculated by Eurocode 4 and AIJ methodologies allows making a conclusion on the sufficient calculation accuracy of the designed mathematical models.

  16. Assessment of feeding value of vegetable-carried pineapple fruit ...

    African Journals Online (AJOL)

    This study compared the sun-drying characteristics of five blends each (w/w; 1:1, 1:1.5, 1:2, 1:2.5, 1:3) of wheat offal-carried pineapple waste (WO:PW) and brewers' dried grains-carried pineapple waste (BDG:PW), assessed the blends for their nutrient contents and the feeding value of the optimum blends with Red Sokoto ...

  17. Integrated Coastal Zone Planning Based on Environment Carrying Capacity Analysis

    Science.gov (United States)

    Miharja, M.; Arsallia, S.

    2017-07-01

    Coastal zone is a crucial area in terms of planning development. It holds high economic value, which affect to increasing number of inhabitants living in the area. As a result, this condition influences environmental degradation. Thus, in every attempt towards coastal zone development, it is crucial to always refer to environment carrying capacity. Carrying capacity is the limit of a certain coastal zone capability to support all human created activities, in which all ecological performances are maintained at sustainable level. The failure to establish strong and clear method and regulation on carrying capacity analysis will lead to a very risky coastal zone development, which in turn would threat the area’s sustainability. This paper discusses method for analysing carrying capacity of coastal zone as important input for the area development plan. Two key parameters, i.e. land and clean water carrying capacities are discussed to form carrying capacity analytical method. Furthermore, an empirical data of Ambon Bay, Moluccas Province, is used to illustrate the operationalization of the method.

  18. Carrying capacity: the tradition and policy implications of limits

    Directory of Open Access Journals (Sweden)

    Virginia Deane Abernethy

    2001-01-01

    Full Text Available ABSTRACT: Within just the last few centuries, science and technology have enlarged human capabilities and population size until humans now take, for their own use, nearly half of the Earth's net terrestrial primary production. An ethical perspective suggests that potentials to alter, or further increase, humanity's use of global resources should be scrutinized through the lenses of self-interested foresightedness and respect for non-human life. Without overtly invoking ethics, studies of the carrying capacity achieve just this objective. Carrying capacity is an ecological concept that expresses the relationship between a population and the natural environment on which it depends for ongoing sustenance. Carrying capacity assumes limits on the number of individuals that can be supported at a given level of consumption without degrading the environment and, therefore, reducing future carrying capacity. That is, carrying capacity addresses long-term sustainability. Worldviews differ in the importance accorded to the carrying capacity concept. This paper addresses three worldviews - ecological, romantic, and entrepreneurial - and explores the ethics and the policy implications of their contrasting perspectives.

  19. Carrying capacity of water resources in Bandung Basin

    Science.gov (United States)

    Marganingrum, D.

    2018-02-01

    The concept of carrying capacity is widely used in various sectors as a management tool for sustainable development processes. This idea has also been applied in watershed or basin scale. Bandung Basin is the upstream of Citarum watershed known as one of the national strategic areas. This area has developed into a metropolitan area loaded with various environmental problems. Therefore, research that is related to environmental carrying capacity in this area becomes a strategic issue. However, research on environmental carrying capacity that has been done in this area is still partial either in water balance terminology, land suitability, ecological footprint, or balance of supply and demand of resources. This paper describes the application of the concept of integrated environmental carrying capacity in order to overcome the increasing complexity and dynamic environmental problems. The sector that becomes the focus of attention is the issue of water resources. The approach method to be carried out is to combine the concept of maximum balance and system dynamics. The dynamics of the proposed system is the ecological dynamics and population that cannot be separated from one another as a unity of the Bandung Basin ecosystem.

  20. [Ecological carrying capacity and Chongming Island's ecological construction].

    Science.gov (United States)

    Wang, Kaiyun; Zou, Chunjing; Kong, Zhenghong; Wang, Tianhou; Chen, Xiaoyong

    2005-12-01

    This paper overviewed the goals of Chongming Island's ecological construction and its background, analyzed the current eco-economic status and constraints of the Island, and put forward some scientific issues on its ecological construction. It was suggested that for the resources-saving and sustainable development of the Island, the researches on its ecological construction should be based on its ecological carrying capacity, fully take the regional characteristics into consideration, and refer the successful development modes at home and abroad. The carrying capacity study should ground on systemic and dynamic views, give a thorough evaluation of the Island's present carrying capacity, simulate its possible changes, and forecast its demands and risks. Operable countermeasures to promote the Island's carrying capacity should be worked out, new industry structure, population scale, and optimized distribution projects conforming to regional carrying capacity should be formulated, and effective ecological security alarming and control system should be built, with the aim of providing suggestions and strategic evidences for the decision-making of economic development and sustainable environmental resources use of the region.

  1. Molecular evidence of vector-borne pathogens in dogs and cats and their ectoparasites in Algiers, Algeria.

    Science.gov (United States)

    Bessas, Amina; Leulmi, Hamza; Bitam, Idir; Zaidi, Sara; Ait-Oudhia, Khatima; Raoult, Didier; Parola, Philippe

    2016-04-01

    In Algeria, only limited information is currently available on the prevalence of emergent canine and feline vector-borne diseases. The aim of the present work was to detect by qPCR vector-associated bacteria in stray dogs and cats and their ectoparasites from Algiers. 18/117 (15.38%) dogs and 2/107 (1.87%) cats were positive for at least one vector-borne agent. Coxiella burnetii and Bartonella henselae were identified in 1/117 (0.85%) dog individually. Ehrlichia canis DNA was detected in 17/117 (14.52%) dogs. 1/107 (0.93%) cat was positive to C. burnetii and another 1/107 (0.93%) to B. henselae. DNA of Rickettsia massiliae, Rickettsia conorii and E. canis was detected in Rhipicephalus sanguineus. Cat fleas were infected with Rickettsia felis, B. henselae and Bartonella clarridgeiae. B. vinsonii subsp. berkhoffii was identified in Xenopsylla cheopis collected from dogs. The findings of this study indicate that dogs and cats from Algeria are exposed to multiple tick and flea-borne pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Evaluation of carrying capacity and territorial environmental sustainability

    Directory of Open Access Journals (Sweden)

    Giuseppe Ruggiero

    2012-09-01

    Full Text Available Land use has a great impact on environmental quality, use of resources, state of ecosystems and socio-economic development. Land use can be considered sustainable if the environmental pressures of human activities do not exceed the ecological carrying capacity. A scientific knowledge of the capability of ecosystems to provide resources and absorb waste is a useful and innovative means of supporting territorial planning. This study examines the area of the Province of Bari to estimate the ecosystems’ carrying capacity, and compare it with the current environmental pressures exerted by human activities. The adapted methodology identified the environmentally sustainable level for one province.

  3. General relativistic galvano-gravitomagnetic effect in current carrying conductors

    International Nuclear Information System (INIS)

    Ahmedov, B.J.

    1998-11-01

    The analogy between general relativity and electromagnetism suggests that there is a galvano-gravitomagnetic effect, which is the gravitational analogue of the Hall effect. This new effect takes place when a current carrying conductor is placed in a gravitomagnetic field and the conduction electrons moving inside the conductor are deflected transversally with respect to the current flow. In connection with this galvano-gravitomagnetic effect, we explore the possibility of using current carrying conductors for detecting the gravitomagnetic field of the Earth. (author)

  4. Carry trade as a speculative investment strategy in Serbia

    Directory of Open Access Journals (Sweden)

    Bungin Sanja

    2012-12-01

    Full Text Available This paper is analyses causes and the consequences of a speculative investment carry trade strategy in the exchange market in Serbia. The presence of such type of investor is related to high yields of risk free securities denominated in dinars, as well as the perception of future movements of dinar exchange rate related to currency that serves as source of investment. The consequences of carry trade may significantly influence exchange rate movements when monetary policy has limited facilities to combat negative and sudden shocks.

  5. Development of heavy load carrying vehicle for nuclear power station

    International Nuclear Information System (INIS)

    Terabayashi, Yasuharu; Oono, Hiroo; Aizu, Takao; Kawaguchi, Kaname; Yamanaka, Masayuki; Hirobe, Tamio; Inagaki, Yoshiaki.

    1985-01-01

    In nuclear power stations, in order to carry out sound and stable operation, the routine inspection and regular inspection of machinery and equipment are performed, therefore, the transportation of heavy things is frequently carried out. Especially, the transportation of heavy things over the steps of passages and stairs requires much labor. Therefore, Chubu Electric Power Co., Inc. and Chubu Plant Service Co., Ltd. carried out the research on the development of a vehicle for transporting heavy components of nuclear power plants. In this research, it was aimed at developing a vehicle which can carry heavy components and get over a step, climb and descend stairs, and run through a narrow passage having many curves as well as running on flat ground. For this purpose, the actual state of the transportation of heavy things was investigated during the regular inspection of a nuclear power station, and on the basis of this results, a prototype vehicle was made and tested. Thereafter, a transporting vehicle of actual scale was made and tested. The investigation of actual state and the examination of the fundamental concept, the design, trial manufacture and verifying test are reported. (Kako, I.)

  6. The KB WOT Fisheries Programme carried out in 2015

    NARCIS (Netherlands)

    Damme, van C.J.G.; Verver, S.W.

    2017-01-01

    The KB WOT Fisheries programme is established to maintain and develop the expertise needed to carry out the statutory obligations of the Netherlands in fisheries monitoring and advice. It is also a flexible program which responds to changes over time in WOT requirements, fisheries management and

  7. Application of Load Carrying Sandwich Elements in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Jensen, Jacob Fisker; Schultz, Jacob Pagh; Berggreen, Carl Christian

    2005-01-01

    The present work investigates the possibilities and drawbacks when applying sandwich as opposed to single skin composites in the flanges of the load carrying spar in a future 180 m wind turbine rotor. FEA is applied to investigate two basic designs with single skin and sandwich flanges respectively...

  8. Charges and Fields in a Current-Carrying Wire

    Science.gov (United States)

    Redzic, Dragan V.

    2012-01-01

    Charges and fields in a straight, infinite, cylindrical wire carrying a steady current are determined in the rest frames of ions and electrons, starting from the standard assumption that the net charge per unit length is zero in the lattice frame and taking into account a self-induced pinch effect. The analysis presented illustrates the mutual…

  9. Carrying capacity of Chaetoceros gracilis in Homa Lagoon and the ...

    African Journals Online (AJOL)

    The possibility for nutrient limitation to affect C. gracilis was assessed from two different ecosystems (Izmir Bay and Homa Lagoon). Our goal was to determine the growth rate of all nutrients and the maximum levels of the C. gracilis phytoplankton biomass (the maximum biomass carrying capacity) on the extent of its full ...

  10. Anthelmintic activity procedure The anthelmintic assay was carried ...

    Indian Academy of Sciences (India)

    Indian adult earthworms Pheretima posthuma. The worms were procured from local supplier at Shimoga at the time of carrying out the experiment. The worms were washed with normal saline to remove all fecal matter used for the anthelmintic study. The earthworms of 4 -6 cm in length and 0.3-0.4 cm in width were used for ...

  11. Cognitive Load in Voice Therapy Carry-Over Exercises

    DEFF Research Database (Denmark)

    Iwarsson, Jenny; Morris, David Jackson; Balling, Laura Winther

    2017-01-01

    Purpose The cognitive load generated by online speech production may vary with the nature of the speech task. This article examines 3 speech tasks used in voice therapy carry-over exercises, in which a patient is required to adopt and automatize new voice behaviors, ultimately in daily spontaneous...

  12. The effect of manufacturing tolerances on the load carrying capacity ...

    Indian Academy of Sciences (India)

    Abstract. This paper deals with simplified 3D finite element (FE) analysis on the effect of manufacturing tolerances on the load carrying capacity of large diameter bearings based on Hertz theory. The nonlinear connector elements are used to model the rolling elements. This model enables us to evaluate the contact load on ...

  13. Stress Carry-Over and College Student Health Outcomes

    Science.gov (United States)

    Pedersen, Daphne E.

    2012-01-01

    Objective: Using a stress carry-over perspective, this study examines the relationship between stress stemming from school and family domains and physical and mental health outcomes. Methods: The study sample included 268 undergraduate men and women from a Midwestern university. Participants completed an anonymous online questionnaire. OLS…

  14. Foreign exchange predictability and the carry trade: a decomposition approach

    Czech Academy of Sciences Publication Activity Database

    Anatolyev, Stanislav; Gospodinov, N.; Jamali, I.; Liu, X.

    2017-01-01

    Roč. 42, June (2017), s. 199-211 ISSN 0927-5398 Institutional support: Progres-Q24 Keywords : exchange rate forecasting * carry trade * return decomposition Subject RIV: AH - Economics OBOR OECD: Finance Impact factor: 0.979, year: 2016

  15. El naturalismo americano: Theodore Dreiser y Sister Carrie

    Directory of Open Access Journals (Sweden)

    Dolores G. ALONSO MULAS

    2009-08-01

    Full Text Available Para situar a un escritor, como Theodore Dreiser, y especialmente su novela Sister Carrie dentro de un movimiento literario y de una etapa determinada de la historia americana, es necesario dar un breve repaso al naturalismo, llegado a América a través de Stephen Crane

  16. How to carry out a clinical audit project

    African Journals Online (AJOL)

    improve patient care and outcomes through systematic review of care against explicit criteria and implementation of change. Aspects of the structure, processes and outcomes of care are selected and systematically evaluated against explicit criteria. ... on admission or perhaps refusal to have the investigations carried out.

  17. Carrying capacity of a heterogeneous lake for migrating swans

    NARCIS (Netherlands)

    Gyimesi, A.

    2010-01-01

    One way to express the value of a natural habitat is its capacity to harbour a particular target species. In the case of migratory birds, the cumulative number of birds that can be accommodated at a site for a given period of time (‘bird-days’) became an accepted currency for this carrying capacity.

  18. An apparatus for carrying and transporting a product

    NARCIS (Netherlands)

    Van Ostayen, R.A.J.; Munnig Schmidt, R.H.; Hong, P.V.

    2014-01-01

    An apparatus for carrying and transporting a product, comprising a conveyor having a surface, which surface is during use directed towards the product and is provided with inlet openings and outlet openings for a medium for supporting and providing the product with traction, wherein the surface is

  19. Can we measure carrying capacity with foraging behavior?

    Science.gov (United States)

    Morris, Douglas W; Mukherjee, Shomen

    2007-03-01

    Carrying capacity is one of the most important, yet least understood and rarely estimated, parameters in population management and modeling. A simple behavioral metric of carrying capacity would advance theory, conservation, and management of biological populations. Such a metric should be possible because behavior is finely attuned to variation in environment including population density. We connect optimal foraging theory with population dynamics and life history to develop a simple model that predicts this sort of adaptive density-dependent change in food consumption. We then confirm the model's unexpected and manifold predictions with field experiments. The theory predicts reproductive thresholds that alter the marginal value of energy as well as the value of time. Both effects cause a pronounced discontinuity in quitting-harvest rate that we revealed with foraging experiments. Red-backed voles maintained across a range of high densities foraged at a lower density-dependent rate than the same animals exposed to low-density treatments. The change in harvest rate is diagnostic of populations that exceed their carrying capacity. Ecologists, conservation biologists, and wildlife managers may thus be able to use simple and efficient foraging experiments to estimate carrying capacity and habitat quality.

  20. Random noise characterization on the carrying capacities of a ...

    African Journals Online (AJOL)

    The process of the survival of species dependent on a limited resource in a polluted environment which isnot a new idea can be described by the technique of a mathematical modelling. We have utilised the technique of a numerical simulation to study the impact of environmental random noise on the carrying capacities of ...

  1. A METHOD OF SECURITY SCANNING OF CARRY-ON ITEMS, AND A CARRY-ON ITEMS SECURITY SCANNING SYSTEM

    DEFF Research Database (Denmark)

    2017-01-01

    A security scanning system (1) comprises a first stage module (3) having at least one X-ray source (6) and at least three first detectors (7) that are line-shaped and arranged in mutually different orientations and have at least dual energy resolution. A group of carry-on items (4) on a carrier...... are scanned simultaneously in the first stage module solely by transmission contrast radiography generating projections of two-dimensional image data. A processing device (9) reconstructs a 3D representation of the carry-on items and analyzes the 3D representation to determine whether further scanning...

  2. Carrying guns in public: legal and public health implications.

    Science.gov (United States)

    Vernick, Jon S

    2013-03-01

    In District of Columbia v. Heller, the U.S. Supreme Court ruled that the Second Amendment protects an individual's right to own handguns in the home for protection, invalidating a Washington, D.C. law banning most handgun possession. The Heller decision, however, provided lower courts with little guidance regarding how to judge the constitutionality of gun laws other than handgun bans. Nevertheless, lower courts have upheld the vast majority of federal, state, and local gun laws challenged since Heller. One area in which some lower courts have disagreed has been the constitutionality of laws regulating the ability to carry firearms in public. This issue may be the next to be addressed by the Supreme Court under its evolving Second Amendment jurisprudence. Courts should carefully consider the negative public health and safety implications of gun carrying in public as they weigh the constitutionality of these laws. © 2013 American Society of Law, Medicine & Ethics, Inc.

  3. Experiments on criticality carried out from 1975 till 1980

    International Nuclear Information System (INIS)

    Heinicke, W.; Tischer, A.; Weber, W.J.

    1981-11-01

    The report on hand includes the experiments on criticality published from 1975 till 1980. About 90 experiments with the most important related data are listed. They are capable of being called up, with the data base system KRITEXP, by 14 different descriptors or printed in any arrangement or order. This is the basis for a global or purposeful verification of the calculating method for criticality safety. The proof of reliability of the calculations for the criticality analysis are immediately relevant for the licencing procedure under atomic law for all plants of the nuclear fuel cycle where nuclear fuels are handled. Since no criticality experiments are being carried out in the Federal Republic of Germany, the data collection on hand will help to fill this gap with regard to the assessment of experiments carried out in other countries. (orig.) [de

  4. [Evolvement of ecological footprint model representing ecological carrying capacity].

    Science.gov (United States)

    Cao, Shu-yan; Xie, Gao-di

    2007-06-01

    Ecological footprint (EF) is an important index of ecological carrying capacity. The original EF model is excellent in simplicity, aggregation, comparability, and lifelikeness in presenting results, but short in predictability, configuration, and applicability. To overcome these shortcomings, many researches were conducted to modify and promote the EF model, and developed it from static with single time scale to diversified ones, which included: 1) time series EF model, 2) input-output analysis based EF model, 3) integrated assessment incorporated EF model, 4) land disturbance degree based EF model, and 5) life cycle analysis based EF model, or component EF model. The function of EF as a measurement of ecological carrying capacity was significantly improved, but its accuracy and integrality still need to be advanced.

  5. Different Ways of Carrying Bags in Mental Retarded Students

    Directory of Open Access Journals (Sweden)

    Saideh-Sadat Mortazavi

    2012-10-01

    Full Text Available School as an educational and social center is linked with various aspects of child’s growth. The impact of objects, tools, and lifestyle on the development of human performance is not hidden from anyone [1].Tasell Lauri, the head of Cairo Praktive in Australia, in a paper warned parents about bags as a tool that students carry every day, and he is believes that many spinal disorders in adults is caused by childhood trauma. Studies on children and patients with special needs and such as myelomenangocele, cerebral palsy, and neurofibromatosis precisely show abnormal growth of spinal disorders, muscle imbalance, wrong posture [2]. Carrying stationery in an inappropriate tool can cause irreversible effects.

  6. Parallel Optimization of a Reversible (Quantum) Ripple-Carry Adder

    DEFF Research Database (Denmark)

    Thomsen, Michael Kirkedal; Axelsen, Holger Bock

    2008-01-01

    ) ripple-carry adder. We optimize this design with a novel parallelization scheme wherein m parallel k-bit CDKM-adders are combined to form a reversible mk-bit ripple-block carry adder with logic depth O(m+k) for a minimal logic depth O(\\sqrt{mk}), thus improving on the mk-bit CDKM-adder logic depth O......(mk). We also show designs for garbage-less reversible set-less-than circuits. We compare the circuit costs of the CDKM and parallel adder in measures of circuit delay, width, gate and transistor count, and find that the parallelized adder offers significant speedups at realistic word sizes with modest...... parallelization overhead....

  7. Gluteus medius and thigh muscles electromyography during load carrying walking

    Directory of Open Access Journals (Sweden)

    Petr Šťastný

    2015-11-01

    Full Text Available This study compares the electromyographic (EMG peak amplitude changes of gluteus medius (Gmed, vastus medialis (VMO, vastus lateralis (VL and biceps femoris (BF during load carrying walking due to the increased load. The percentage of maximum isometric voluntary contractions (%MVIC of both limbs and 3D kinematic of lower limbs were detected on eighteen resistance-trained men (mean age ± SD, 31 ± 3.4 years while carrying loads of 25, 50 and 75% of their body mass (BM. The repeated measurement ANOVA was used to evaluate the differences in muscles %MVIC and 3D kinematics at all load conditions. Significant differences were found for Gmed %MVIC (F3,99 = 19.8, p < 0.001. Gmed activity was significantly different between load carrying walking with 25% of BM (mean ± SD, 20 ± 12%MVIC, 50% of BM (32 ± 17%MVIC and 75% of BM (45 ± 26%MVIC condition. Differences were found in hip flexion at Gmed EMG peak (F3,96 = 14, p < 0.001, between 25% of BM (18 ± 11° and 50% of BM (29 ± 7°. No significant differences were found for thigh muscles, when thigh muscle activity did not exceed 30%MVIC even at 75% of BM condition. Load carrying walking is an exercise which activates Gmed more than thigh muscles. This exercise increases the Gmed activity along with increased loads and it should be regarded as a complex Gmed strengthening exercise. This exercise is recommended for strengthening the Gmed with low activation of VL and VMO.

  8. Digitization Projects Carried out by the Mathematical Institute Belgrade

    OpenAIRE

    Ognjanovič, Zoran; Mijajlovič, Žarco

    2004-01-01

    In this paper some current digitization projects carried out by the Mathematical Institute of Serbian Academy of Science and Arts Belgrade and the Faculty of Mathematics Belgrade are described. The projects concern developing of a virtual library of retro-digitized books and an Internet data base and presentation of electronic editions of some leading Serbian journals in science and arts, and the work on the South-Eastern European Digitization Initiative (SEEDI).

  9. Hydrodynamic pressure, carrying capacities, friction forces in biobearing gap.

    Science.gov (United States)

    Wierzcholski, Krzysztof Ch

    2009-01-01

    The present paper deals with the calculations of the pressure distributions, carrying capacities and friction forces derivations in a super- thin layer of biological synovial fluid inside the slide biobearing gap limited by a spherical, conical, cylindrical, parabolic, hyperbolic bone heads. There are also described unsteady and random flow conditions of the bio-bearing lubrication with the changes of the dynamic viscosity of the synovial fluid in the gap height in general.

  10. The calming effect of maternal carrying in different mammalian species

    Directory of Open Access Journals (Sweden)

    Gianluca eEsposito

    2015-04-01

    Full Text Available Attachment theory postulates that mothers and their infants possess some basic physiological mechanisms that favour their dyadic interaction and bonding. Many studies have focused on the maternal physiological mechanisms that promote attachment (e.g. mothers’ automatic responses to infant faces and/or cries, and relatively less have examined infant physiology. Thus, the physiological mechanisms regulating infant bonding behaviors remain largely undefined. This review elucidates some of the neurobiological mechanisms governing social bonding and cooperation in humans by focusing on maternal carrying and its beneficial effect on mother-infant interaction in mammalian species (e.g. in humans, big cats and rodents. These studies show that infants have a specific calming response to maternal carrying. A human infant carried by his/ her walking mother exhibits a rapid heart rate decrease, and immediately stops voluntary movement and crying compared to when he/ she is held in a sitting position. Furthermore, strikingly similar responses were identified in mouse rodents, who exhibit immobility, diminished ultra-sonic vocalizations and heart rate. In general, the studies described in the current review demonstrate the calming effect of maternal carrying to be comprised of a complex set of behavioral and physiological components, each of which has a specific postnatal time window and is orchestrated in a well-matched manner with the maturation of the infants. Such reactions could have been evolutionarily adaptive in mammalian mother-infant interactions. The findings have implications for parenting practices in developmentally normal populations. In addition, we propose that infants’ physiological response may be useful in clinical assessments as we discuss possible implications on early screening for child psychopathology (e.g. Autism Spectrum Disorders, and Perinatal Brain Disorders.

  11. Superpositions of light fields carrying orbital angular momentum

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2012-01-01

    Full Text Available OF LIGHT FIELDS CARRYING ORBITAL ANGULAR MOMENTUM By Angela Dudley A thesis submitted in fulfilment of the academic requirements for the PhD degree of Science in the School of Chemistry and Physics, University of KwaZulu-Natal, Durban... this dissertation for submission. _________________________________ Prof Andrew Forbes On this_______day of____________________________2012 iv Declaration 2 - Plagiarism I, ???????????????. declare that 1...

  12. Plant Agricultural Streptomycin Formulations Do Not Carry Antibiotic Resistance Genes▿

    OpenAIRE

    Rezzonico, Fabio; Stockwell, Virginia O.; Duffy, Brion

    2009-01-01

    Streptomycin is used in plant agriculture for bacterial disease control, particularly against fire blight in pome fruit orchards. Concerns that this may increase environmental antibiotic resistance have led to bans or restrictions on use. Experience with antibiotic use in animal feeds raises the possible influence of formulation-delivered resistance genes. We demonstrate that agricultural streptomycin formulations do not carry producer organism resistance genes. By using an optimized extracti...

  13. On Kolmogorov Complexity and the Costs of Carrying out Strategies

    OpenAIRE

    Justin Smith

    2000-01-01

    It is common to model costs of carrying out strategies in games in relation to the complexity, in some sense, of the strategies. We show a particularly general definition of complexity for this purpose, one that subsumes many alternatives as special cases. We explore how this definition can be used and developed, and illustrate with applications to the analysis of two player finite repeated games.

  14. Apollo 11 Astronaut Aldrin Carries Equipment on Lunar Surface

    Science.gov (United States)

    1969-01-01

    The first manned lunar landing mission, Apollo 11, launched from the Kennedy Space Center (KSC) in Florida via the Marshall Space Flight Center (MSFC) developed Saturn V launch vehicle on July 16, 1969 and safely returned to Earth on July 24, 1969. Aboard the space craft were astronauts Neil A. Armstrong, commander; Michael Collins, Command Module (CM) pilot; and Edwin E. (Buzz) Aldrin Jr., Lunar Module (LM) pilot. The CM, piloted by Michael Collins, remained in a parking orbit around the Moon, while the LM, named 'Eagle'', carrying astronauts Armstrong and Aldrin, landed on the Moon in the Sea of Tranquility. During 2½ hours of surface exploration, the crew set up experiments, collected 47 pounds of lunar surface material for analysis back on Earth, planted the U.S Flag, and left a message for all mankind. In this photograph, Aldrin walks past some rocks, easily carrying scientific equipment which would have been too heavy to carry on Earth. The two packages made up the Early Apollo Scientific Experiment Package (EASEP) on Apollo 11. On the left is the Passive Seismic Experiment Package (PSEP) and on the right is the Laser Ranging Retroreflector (LRR).

  15. Magnetohydrodynamic sausage waves in current-carrying coronal tubes

    Science.gov (United States)

    Bahari, Karam

    2017-09-01

    Magnetohydrodynamic (MHD) sausage waves in a coronal loop consisting of a core with longitudinal magnetic field and a current-carrying annulus with azimuthal magnetic field in the presence of plasma pressure are studied. As the plasma pressure is introduced to the loop a narrow band of infinite slow waves appear in the dispersion diagram, and the oscillation frequency of the fast sausage waves increases. In the loops with thinner annulus, more fast sausage waves with higher radial mode numbers are supported by the loop, and the fast sausage waves have smaller cut off wave numbers. The eigenfunction of the long wavelength fast sausage wave supported by the current-carrying loop, in the case of low density contrast, is similar to the eigenfunction of the slow sausage wave in a straight homogeneous loop with the maximum frequency of the frequency band. Other slow sausage waves both in a straight homogeneous loop and a current-carrying loop do not perturb the surrounding environment substantially.

  16. Violence and weapon carrying in music videos. A content analysis.

    Science.gov (United States)

    DuRant, R H; Rich, M; Emans, S J; Rome, E S; Allred, E; Woods, E R

    1997-05-01

    The positive portrayal of violence and weapon carrying in televised music videos is thought to have a considerable influence on the normative expectations of adolescents about these behaviors. To perform a content analysis of the depictions of violence and weapon carrying in music videos, including 5 genres of music (rock, rap, adult contemporary, rhythm and blues, and country), from 4 television networks and to analyze the degree of sexuality or eroticism portrayed in each video and its association with violence and weapon carrying, as an indicator of the desirability of violent behaviors. Five hundred eighteen videos were recorded during randomly selected days and times of the day from the Music Television, Video Hits One, Black Entertainment Television, and Country Music Television networks. Four female and 4 male observers aged 17 to 24 years were trained to use a standardized content analysis instrument. Interobserver reliability testing resulted in a mean (+/- SD) percentage agreement of 89.25% +/- 7.10% and a mean (+/- SD) kappa of 0.73 +/- 0.20. All videos were observed by rotating 2-person, male-female teams that were required to reach agreement on each behavior that was scored. Music genre and network differences in behaviors were analyzed with chi 2 tests. A higher percentage (22.4%) of Music Television videos portrayed overt violence than Video Hits One (11.8%), Country Music Television (11.8%), and Black Entertainment Television (11.5%) videos (P = .02). Rap (20.4%) had the highest portrayal of violence, followed by rock (19.8%), country (10.8%), adult contemporary (9.7%), and rhythm and blues (5.9%) (P = .006). Weapon carrying was higher on Music Television (25.0%) than on Black Entertainment Television (11.5%), Video Hits One (8.4%), and Country Music Television (6.9%) (P music videos are between 3 and 4 minutes long, these data indicate that even modest levels of viewing may result in substantial exposure to violence and weapon carrying, which is

  17. Estimating cetacean carrying capacity based on spacing behaviour.

    Directory of Open Access Journals (Sweden)

    Janelle E Braithwaite

    Full Text Available Conservation of large ocean wildlife requires an understanding of how they use space. In Western Australia, the humpback whale (Megaptera novaeangliae population is growing at a minimum rate of 10% per year. An important consideration for conservation based management in space-limited environments, such as coastal resting areas, is the potential expansion in area use by humpback whales if the carrying capacity of existing areas is exceeded. Here we determined the theoretical carrying capacity of a known humpback resting area based on the spacing behaviour of pods, where a resting area is defined as a sheltered embayment along the coast. Two separate approaches were taken to estimate this distance. The first used the median nearest neighbour distance between pods in relatively dense areas, giving a spacing distance of 2.16 km (± 0.94. The second estimated the spacing distance as the radius at which 50% of the population included no other pods, and was calculated as 1.93 km (range: 1.62-2.50 km. Using these values, the maximum number of pods able to fit into the resting area was 698 and 872 pods, respectively. Given an average observed pod size of 1.7 whales, this equates to a carrying capacity estimate of between 1187 and 1482 whales at any given point in time. This study demonstrates that whale pods do maintain a distance from each other, which may determine the number of animals that can occupy aggregation areas where space is limited. This requirement for space has implications when considering boundaries for protected areas or competition for space with the fishing and resources sectors.

  18. Physical fitness of young women: carrying simulated patients.

    Science.gov (United States)

    von Restorff, W

    2000-06-01

    An evaluation of physical fitness prior to employment appears to be mandatory for several occupations in order to protect the employee from overburdening and the employer from placing excess demands on the employee. One such occupation seems to be that of the field medical specialist who needs special physical strength since terrain conditions deny wheel-assisted transport of stretcher patients. The anthropometric and isometric force data of a total of 62 female and 48 male recruits for the medical service of the Bundeswehr were evaluated, together with their ability to carry a patient on a stretcher (weight = 14 kg) within a gymnasium. Initially the 'casualties' were simulated by sandbags weighing 60, 70, 80 and 90 kg each on stretchers; subsequently equivalent-weight water cans were used. The tests were administered at the beginning and at the end of the general Basic Military Training (BMT). While all males were able to carry the simulated 90 kg patient, only 22 out of 62 female recruits were able to do so at the beginning of BMT. At the end, the number had improved to 29 out of 55 women soldiers completing training. At the beginning of BMT 22.5% of the women soldiers were unable to rescue a simulated 70 kg patient; at the end of BMT the number had fallen to 18%. The isometric force values as measured revealed the hand grip strength as the best predictor for the capacity to carry simulated 90 kg patients. It is, therefore, suggested that a hand strength test be administered prior to field medical specialist training in order to channel unsuitable candidates into other training schemes.

  19. Care for patients carrying out dialysis therapy at home.

    Science.gov (United States)

    Imada, Akio

    2012-01-01

    The goal of home dialysis is to more successfully reintegrate dialysis patients with high activities in daily life (ADL) into society as compared to hemodialysis (HD), which is carried out at a dialysis facility. By achieving this goal, this therapy can prove to be more effective than renal plantation, which has been carried out only in a few cases in Japan. Since self-management forms the basis of home dialysis, dialysis complications can be reduced by arranging meals, fluid management and dialysis schedule according to the lifestyle of the patient himself. In addition, long-term survival rate with health conditions similar to that of a healthy person can be increased. On the other hand, the goal of home dialysis for dialysis patients with a lower ADL is to strengthen the family bond, and improve quality of life and life prognosis, since nursing and support from family members are essential to ensure a long-term survival rate and ADL. For safe operation of home dialysis, which can be more effective than HD carried out in dialysis facilities, it is important for doctors, nurses, clinical engineers, social workers and all other members of the dialysis staff to work together as a united team. The type of nursing varies depending on period (during conservative treatment of end-stage renal disease, during the introduction and maintenance of dialysis, and when changing to end-stage renal disease replacement therapy). It also varies depending on whether continuous ambulatory peritoneal dialysis or home hemodialysis is implemented. The important points of nursing in home dialysis for each treatment period, depending on whether by continuous ambulatory peritoneal dialysis and home hemodialysis, are summarized here. Copyright © 2012 S. Karger AG, Basel.

  20. Killing cancer cells by targeted drug-carrying phage nanomedicines

    Directory of Open Access Journals (Sweden)

    Yacoby Iftach

    2008-04-01

    Full Text Available Abstract Background Systemic administration of chemotherapeutic agents, in addition to its anti-tumor benefits, results in indiscriminate drug distribution and severe toxicity. This shortcoming may be overcome by targeted drug-carrying platforms that ferry the drug to the tumor site while limiting exposure to non-target tissues and organs. Results We present a new form of targeted anti-cancer therapy in the form of targeted drug-carrying phage nanoparticles. Our approach is based on genetically-modified and chemically manipulated filamentous bacteriophages. The genetic manipulation endows the phages with the ability to display a host-specificity-conferring ligand. The phages are loaded with a large payload of a cytotoxic drug by chemical conjugation. In the presented examples we used anti ErbB2 and anti ERGR antibodies as targeting moieties, the drug hygromycin conjugated to the phages by a covalent amide bond, or the drug doxorubicin conjugated to genetically-engineered cathepsin-B sites on the phage coat. We show that targeting of phage nanomedicines via specific antibodies to receptors on cancer cell membranes results in endocytosis, intracellular degradation, and drug release, resulting in growth inhibition of the target cells in vitro with a potentiation factor of >1000 over the corresponding free drugs. Conclusion The results of the proof-of concept study presented here reveal important features regarding the potential of filamentous phages to serve as drug-delivery platform, on the affect of drug solubility or hydrophobicity on the target specificity of the platform and on the effect of drug release mechanism on the potency of the platform. These results define targeted drug-carrying filamentous phage nanoparticles as a unique type of antibody-drug conjugates.

  1. Astronaut Edgar Mitchell carries penetrometer attached to handle during EVA

    Science.gov (United States)

    1971-01-01

    Astronaut Edgar D. Mitchell, lunar module pilot, carries the penetrometer attached to an extension handle during extravehicular activity on the lunar surface. The geophone alignment flag is attached to the penetrometer. Several components of the Apollo Lunar Surface Experiments Package (ALSEP) are in the background. The shadow of Astronaut Alan B. Shepard Jr., commander, who took this photograph, is in the foreground, near several prints made by lunar overshoes of the two astronauts and a long track made by a wheel of the Modularized Equipment Transporter (MET).

  2. Nonlinear vibration of an axially loaded beam carrying rigid bodies

    Directory of Open Access Journals (Sweden)

    O. Barry

    2016-12-01

    Full Text Available This paper investigates the nonlinear vibration due to mid-plane stretching of an axially loaded simply supported beam carrying multiple rigid masses. Explicit expressions and closed form solutions of both linear and nonlinear analysis of the present vibration problem are presented for the first time. The validity of the analytical model is demonstrated using finite element analysis and via comparison with the result in the literature. Parametric studies are conducted to examine how the nonlinear frequency and frequency response curve are affected by tension, rotational inertia, and number of intermediate rigid bodies.

  3. Plant agricultural streptomycin formulations do not carry antibiotic resistance genes.

    Science.gov (United States)

    Rezzonico, Fabio; Stockwell, Virginia O; Duffy, Brion

    2009-07-01

    Streptomycin is used in plant agriculture for bacterial disease control, particularly against fire blight in pome fruit orchards. Concerns that this may increase environmental antibiotic resistance have led to bans or restrictions on use. Experience with antibiotic use in animal feeds raises the possible influence of formulation-delivered resistance genes. We demonstrate that agricultural streptomycin formulations do not carry producer organism resistance genes. By using an optimized extraction procedure, Streptomyces 16S rRNA genes and the streptomycin resistance gene strA were not detected in agricultural streptomycin formulations. This diminishes the likelihood for one potential factor in resistance development due to streptomycin use.

  4. Necking down of sausages in current-carrying plasma pinches

    Energy Technology Data Exchange (ETDEWEB)

    Trubnikov, B.A.; Zhdanov, S.K.

    1986-07-01

    The evolution of long-wave perturbations is shown to be equivalent, for various unstable media, to the dynamics of a gas with a negative adiabatic index ..gamma... This evolution is described (for various values at N) by the quasi-Chaplygin system of equations Several examples of such media are considered, including a ''Chaplygin gas'' (N = 3), drops on a ceiling or ''solitons which have broken'' (N = 0), necks in a current-carrying plasma pinch with a skin effect, for both incompressible and compressible models (N = 2), and the breakup of liquid jets into drops (N = 3/2). A principle for selecting evolutionary solutions corresponding to the absence of perturbations in the limit t ..-->.. -infinity is formulated. In the cases N = 0 and N = 2, a hodograph transformation reduces system (1) to a magnetostatic equation (..delta..A)/sub phi/ = -(4..pi../c)j/sub phi/ and all the instability modes are equivalent to multipoles of circular currents which are localized on a circle. Exact solutions are given for periodic and isolated (localized) perturbations. The breakup of a medium into distinct blobs, in particular, the rupture of necks in a current-carrying plasma pinch, is demonstrated.

  5. Langkawi Island, Social Aspect and the Carrying Capacity

    Directory of Open Access Journals (Sweden)

    Mohamad Diana

    2014-01-01

    Full Text Available The aptitude to convince a range of preferences has facilitated the island tourism attractions to achieve international recognition and at present KILIM Geopark is enjoyed by a prominent percentage of individuals wide-reaching. Conventional knowledge has that the island attractions are operating on the limited immobile resources, of which, have raised the scholars’ concerns over the carrying capacity issue. When analyzing carrying capacity, scholars have traditionally focused on the environmental part, hence, this working paper is motivated to convey onto the table issues relating to the social characteristics. This particular paper employed the self-administered questionnaire survey instrument which was structured to answer the two-fold objective specifically the tourists’ satisfaction level with their tourism experience and knowledge gap in relation to improving the island tourism. Targeting the tourists with minimum age of 18, this working paper collects information on the tourists’ perception towards hospitality, facilities and safety issues. In addition, this working paper comes to scrutinize different results of demographic factors as compared to what have been documented by earlier studies. Besides, it is learned that ‘safety issue’ variable plays an important role when it comes to the following factors: tourist arrival, access to facilities and tourism experience.

  6. Necking down of sausages in current-carrying plasma pinches

    International Nuclear Information System (INIS)

    Trubnikov, B.A.; Zhdanov, S.K.

    1986-01-01

    The evolution of long-wave perturbations is shown to be equivalent, for various unstable media, to the dynamics of a gas with a negative adiabatic index γ. This evolution is described (for various values at N) by the quasi-Chaplygin system of equations Several examples of such media are considered, including a ''Chaplygin gas'' (N = 3), drops on a ceiling or ''solitons which have broken'' (N = 0), necks in a current-carrying plasma pinch with a skin effect, for both incompressible and compressible models (N = 2), and the breakup of liquid jets into drops (N = 3/2). A principle for selecting evolutionary solutions corresponding to the absence of perturbations in the limit t → -∞ is formulated. In the cases N = 0 and N = 2, a hodograph transformation reduces system (1) to a magnetostatic equation (ΔA)/sub phi/ = -(4π/c)j/sub phi/ and all the instability modes are equivalent to multipoles of circular currents which are localized on a circle. Exact solutions are given for periodic and isolated (localized) perturbations. The breakup of a medium into distinct blobs, in particular, the rupture of necks in a current-carrying plasma pinch, is demonstrated

  7. c-Myc-Induced Extrachromosomal Elements Carry Active Chromatin

    Directory of Open Access Journals (Sweden)

    Greg Smith

    2003-03-01

    Full Text Available Murine Pre-13 lymphocytes with experimentally activated MycER show both chromosomal and extrachromosomal gene amplification. In this report, we have elucidated the size, structure, functional components of c-Myc-induced extrachromosomal elements (EEs. Scanning electron microscopy revealed that EEs isolated from MycER-activated Pre-B+ cells are an average of 10 times larger than EEs isolated from non-MycER-activated control Pre-B- cells. We demonstrate that these large c-Myc-induced EEs are associated with histone proteins, whereas EEs of non-MycER-activated Pre B- cells are not. Immunohistochemistry and Western blot analyses using pan -histone-specific, histone H3 phosphorylation-specific, histone H4 acetylation-specific antibodies indicate that a significant proportion of EEs analyzed from MycER-activated cells harbors transcriptionally competent and/or active chromatin. Moreover, these large, c-Myc-induced EEs carry genes. Whereas the total genetic make-up of these c-Myc-induced EEs is unknown, we found that 30.2% of them contain the dihydrofolate reductase (DHFR gene, whereas cyclin C (CCNC was absent. In addition, 50% of these c-Myc-activated Pre-B+ EEs incorporated bromodeoxyuridine (BrdU, identifying them as genetic structures that self-propagate. In contrast, EEs isolated from non-Myc-activated cells neither carry the DHFR gene nor incorporate BrdU, suggesting that c-Myc deregulation generates a new class of EEs.

  8. Opa protein repertoires of disease-causing and carried meningococci.

    Science.gov (United States)

    Callaghan, Martin J; Buckee, Caroline; McCarthy, Noel D; Ibarz Pavón, Ana Belén; Jolley, Keith A; Faust, Saul; Gray, Stephen J; Kaczmarski, Edward B; Levin, Michael; Kroll, J Simon; Maiden, Martin C J; Pollard, Andrew J

    2008-09-01

    The meningococcal Opa proteins play an important role in pathogenesis by mediating invasion of human cells. The aim of this investigation was to determine whether carried and disease-associated meningococci possess different Opa repertoires and whether the diversity of these proteins is associated with clinical severity of disease. Opa repertoires in 227 disease-associated meningococci, isolated in the United Kingdom over a period of 6 years, were compared to the repertoires in 190 asymptomatically carried meningococci isolated in the United Kingdom from a contemporary, nonepidemic period. Multidimensional scaling (MDS) was employed to investigate the association between Opa repertoires and multilocus sequence typing (MLST) genotypes. Associations with clinical severity were also analyzed statistically. High levels of diversity were observed in opa alleles, variable regions, and repertoires, and MDS revealed that MLST genotypes were strongly associated with particular Opa repertoires. Individual Opa proteins or repertoires were not associated with clinical severity, though there was a trend toward an association with the opaD locus. Meningococcal Opa repertoire is strongly linked to MLST genotype irrespective of epidemiological sampling and therefore correlates with invasiveness. It is not, however, strongly associated with severity of meningococcal disease.

  9. Oxygen carrying perfluorochemical emulsion as an adjuvant to radiation therapy

    International Nuclear Information System (INIS)

    Teicher, B.A.; Rose, C.M.

    1984-01-01

    The potential of a perfluorochemical emulsion which as an excellent carrying capacity for oxygen to enhance the ability of radiation therapy to delay the growth of Lewis lung tumor was examined. There was a highly significant effect produced by the addition of perfluorochemical emulsion and carbogen breathing in combination with irradiation. With single dose x-ray treatment the dose of perfluorochemical emulsion was varied from 0.05-0.6 ml addition to the blood volume of the animals. The dose response effect was very broad peaking at 0.3-0.4 ml which gave a dose modifying effect of 2.8 +- 0.6 with 1000 rad of x-rays. The addition of 0.3 ml of perfluorochemical free annex solution with carbogen breathing produced a small enhancement in tumor growth delay addition of the same volume of the complete emulsion increased the tumor growth delay time about 3-fold compared to the annex solution. When the perfluorochemical emulsion was added to a fractionated course of radiation therapy a dose modifying effect of 1.8 +- 0.3 was obtained. Oxygen carrying perfluorochemical emulsions may provide a nontoxic clinically useful means of increasing the effectiveness of radiation therapy and of certain chemotherapeutic agents

  10. Extinguishing experiments of sodium fires carried out by TNO

    International Nuclear Information System (INIS)

    Meijer, G.J.A.M.; Rulkens, W.H.

    1979-01-01

    For the collection of burning sodium from the components and pipes of the secondary circuit of SNR 300, spill-trays are foreseen which are connected to dump tanks. These spill-trays are covered with a sieve in order to reduce the flow of air to the sodium in the spill-tray and hence to reduce the burning rate. In order to further minimize the consequences of a large sodium fire for the components, the licensing authority required as a back-up the installation of a remotely operated distribution system by means of which an extinguishing powder can be sprayed upon the spill-trays. Experiments were carried out in which the effectiveness of different extinguishing powders in combination with the sieve covered spill-trays were tested in a comparative manner. Attention was paid to the question whether such a spray system would have also additional benefits in the case of smaller sodium leaks. To this purpose three commercially available extinguishing powders were tested, one on a sodium chloride, two on a carbonate base. Also the effectiveness of the sieves proper with respect to reducing the burning rate was tested without applying any extinguishing powders. Finally for a reference some tests were done on open spill-trays, i.e. spill-trays not covered with a sieve.The investigations which were carried out in 1976-1977 were limited to fire experiments, aspects of transport of the powder in the distribution system were not investigated

  11. Elastic-plastic load-carrying capacity of steel members

    Directory of Open Access Journals (Sweden)

    Juhas Pavol

    2018-01-01

    Full Text Available The load-carrying capacity of steel structures and members subjected mostly to bending depends in large measure on local stability of their compressed flanges and bending webs in decided cross-sections and areas. Depending on local stability, the elastic or plastic, eventually the elastic-plastic analysis and design can be applied. The actual standards for design of steel structures contain relatively detailed rules for elastic analysis by the elastic theory and for plastic analysis by the plastic theory. The elastic-plastic analysis and design of steel members are meanwhile still problematic from theory, standard and application point of view. The real elastic-plastic behavior of the steel members is complicated strength and stability problem. Therefore, the representative experimental knowledge and results about the real elastic-plastic behavior and mechanisms of failure of the steel members have been very important from the scientific and applied aspects. The author of paper realized in previous time the wide experimental research within the range of this intention. The paper contains selected knowledge and results of the previous experimental-theoretical investigation of the elastic-plastic local stability of the steel members subjected mostly to bending. The adequate slenderness – strain relation and methodology for practical calculation of the elastic-plastic bending load-carrying capacity of the steel cross-sections and members are presented in the paper.

  12. Assessment of Carrying Capacity of Timber Element Using SBRA Method

    Science.gov (United States)

    Kraus, Michal

    2017-10-01

    Wood as a building material has a significant perspective in the context of nonrenewable energy sources and production of greenhouse gas emissions. The subject of this paper is to verify the carrying capacity of the timber element using the probabilistic method Simulation Based Reliability Assessment (SBRA). The simulation is performed for one million cycles. Key factors decreasing the strength of wooden material at the time include the duration of the loads, and combinations thereof. Inconsiderable factor affecting the strength of wood is also the humidity. Continuous beam with three fields (length 15 m, glued laminated timber, and strength class GL 36 according to the DIN EN 1194) is placed in an environment with a thermal-humidity regime of the 2nd class according to the EC 5. Average life of carrying timber structure is estimated to be 50 years. The simulation results show that there is no risk of failure of wood during the first year. The probability of failure is common in the 10 years of its life. Then, wooden element already meets only a reduced level of reliability.

  13. Modelling of carry-over in recovery furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Fakhrai, Reza [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Metallurgy

    2000-04-01

    Development of mathematical modelling of the combustion process in the furnace of recovery boilers is the subject of this work. This work as a continuation of many years of modelling efforts carried out at KTH/Vaerme- och Ugnsteknik focussed particularly on: char bed modelling; droplets-wall interaction modelling; and carry-over modelling. The char bed model has been studied. Droplets/parcels were considered as a single reactor working independently of the other droplets. The mass of the droplets was not distributed uniformly but induced in the landing place. The droplets hitting the char bed will stick to it and they are alive and part of the calculation. In this way the distribution of the mass on the char bed is only dependent on the parameters which effect flight history such as droplet/parcel diameter, boilers flow field, etc. The droplet- wall interaction model has been studied and found to be very important for obtaining the correct temperature distribution in the recovery furnace. The new approach is based on removal of droplets which hits the wall in the upper part of the recovery boiler from carryover calculation. This model has been proposed and implemented into the GRFM (General Recovery Furnace Model). The carryover modelling effort was based on mass balance in which the number and physical statistics of the droplets/parcel were estimated and the amount of unburned mass was calculated. All of the above listed models were tested together with all other models of heat and mass transfer processes in recovery furnaces using a GRFM. Three-dimensional numerical simulations of the industrial recovery boiler (63 kg/s, 82 bar, 480 deg C) were performed. The number of grid was 232,000 and the number of air ports in this simulation was 178. The air entering the furnace by these ports has different flow rates. Flow and temperature fields as well as species distributions were calculated. The results show good agreement with previously published data and modelling

  14. Time dependent variation of carrying capacity of prestressed precast beam

    Science.gov (United States)

    Le, Tuan D.; Konečný, Petr; Matečková, Pavlína

    2018-04-01

    The article deals with the evaluation of the precast concrete element time dependent carrying capacity. The variation of the resistance is inherited property of laboratory as well as in-situ members. Thus the specification of highest, yet possible, laboratory sample resistance is important with respect to evaluation of laboratory experiments based on the test machine loading capabilities. The ultimate capacity is evaluated through the bending moment resistance of a simply supported prestressed concrete beam. The probabilistic assessment is applied. Scatter of random variables of compressive strength of concrete and effective height of the cross section is considered. Monte Carlo simulation technique is used to investigate the performance of the cross section of the beam with changes of tendons’ positions and compressive strength of concrete.

  15. MRSA carrying mecC in captive mara

    DEFF Research Database (Denmark)

    Gongora, Carmen Espinosa; Harrison, Ewan M; Moodley, Arshnee

    2015-01-01

    OBJECTIVES: To characterize the staphylococcal cassette chromosome mec (SCCmec), virulence and antimicrobial susceptibility of Staphylococcus aureus ST130 isolated from mara (Dolichotis patagonum), a large rodent species native to South America and kept in captivity at Copenhagen Zoo. METHODS......: The presence of mecC was confirmed by PCR in 15 S. aureus ST130 isolated from mara during a previous study. WGS was performed on two randomly selected isolates to characterize their genomes with respect to SCCmec, virulence and resistance gene content. Antimicrobial susceptibility was tested using commercial...... broth microdilution tests. RESULTS: All the isolates belonged to spa type t528 ST130 and carried mecC. Based on WGS, mecC was 100% identical to the prototype sequence of S. aureus strain LGA251. The sequence of SCCmec type XI in the mara isolates had 23 SNPs compared with the one described in LGA251...

  16. A portable virtual machine target for proof-carrying code

    DEFF Research Database (Denmark)

    Franz, Michael; Chandra, Deepak; Gal, Andreas

    2005-01-01

    Virtual Machines (VMs) and Proof-Carrying Code (PCC) are two techniques that have been used independently to provide safety for (mobile) code. Existing virtual machines, such as the Java VM, have several drawbacks: First, the effort required for safety verification is considerable. Second and more...... are the sizes of the proofs and the fact that the certified code is no longer machine-independent. In this paper, we describe work in progress on combining these approaches. Our hybrid safe-code solution uses a virtual machine that has been designed specifically to support proofcarrying code, while...... simultaneously providing efficient justin-time compilation and target-machine independence. In particular, our approach reduces the complexity of the required proofs, resulting in fewer proof obligations that need to be discharged at the target machine....

  17. Carry Trade e Risco Cambial: um Conto de Dois Fatores

    Directory of Open Access Journals (Sweden)

    Alex Luiz Ferreira

    2015-12-01

    Full Text Available Retornos da estratégia de carry trade tem sido explicados usando-se funções de utilidade inseparáveis no tempo que permitem prêmios de risco voláteis. Tipicamente tais funções mimetizam as preferências de economia fechada que dependem de bens duráveis e não duráveis. Este trabalho retorna a uma classificação mais tradicional, em macroeconomia internacional, de consumo entre bens domésticos e importados. O modelo é aplicado para países que representam 98,2% do volume mundial do comércio bilateral de câmbio. Reporta-se uma melhora acentuada na significância dos betas de consumo.

  18. Carrying capacity of the eastern ecological gradient of Kenya.

    Science.gov (United States)

    Bernard, F E; Campbell, D J; Thom, D J

    1989-01-01

    Kenya's rate of natural population increase exceeds 4.0%/year. At this rate, Kenya's population of 23.5 million will expand to 35 million by the year 2000. Rural migrants are being forced out of the highlands into marginal arid and semiarid regions to the east and south in the eastern ecological gradient including Meru, Kitui, Machakos, and Kajiado districts. The people have become victims of marginalization by which the productivity of a unit of land declines relative to the demands of its occupants. The concept of carrying capacity means the number of people a given area can sustain over the long term. In Maasailand, 3.5 standard stock units (450 kg each) are required per adult equivalent for full subsistence, about 7 cows/person. For the Maasai pastoralists, carrying capacities were examined at 2 levels of subsistence: 100% from the herds and 80% from the herds; 2 technological levels; and population-growth rates of 2%, 2.5%, and 3%/annum. Using the median, 3.5%/year, population-growth scenario these districts will have almost 5 million inhabitants in the year 2000. Poverty at technology level I for 40% of them, or for 2 million people, is implausible. Technology level II implies that current rural-development programs will succeed with technological innovations for farm households, access to credit, and markets for their produce. Level II is likely to prevail toward the end of the century for the majority of farmers. Level III necessitates best agricultural and livestock technology as well as the best management. At most, 25% of the households of the eastern ecological gradient could enter this realm by the year 2000. Current strategies of voluntary family planning, rural development emerging from an antiquated extension system, inability to address inequity in land distribution, and laissez-faire resource management are inadequate to deal with the pace of change.

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

    Directory of Open Access Journals (Sweden)

    Wenping Gong

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

  20. Tumor uptake of /sup 67/Ga-carrying liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Ogihara, Izumi; Kojima, Shuji; Kubodera, Akiko; Jay, M.

    1986-02-01

    The in vivo distribution, excretion, and tumor localization of liposome-encapsulated /sup 67/Ga in normal and Ehrlich tumor (solid form)-bearing mice were studied. In normal mice, multilamellar vesicles (MLVs) were taken up mainly be the liver and spleen, whereas small, unilamellar vesicles (SUVs) exhibited a broader tissue distribution. When /sup 67/Ga was encapsulated in MLVs or SUVs, the excretion of the radiotracer in the urine and feces was less than that observed for free tracer at 72 h after i.v. administration. In tumor-bearing mice, SUVs were formed to accumulate preferentially in tumors. The tumor uptake of neutral, positive, and negative SUVs was 10%-13% of the administered dose per gram of tumor tissue at 24 h after their injection. These values were about three times higher than those found for free /sup 67/Ga-nitrilotriacetic acid trisodium salt (NTA) or /sup 67/Ga-citrate. Significant differences in tumor uptake due to different surface charges of liposomes were not observed. Enhanced tumor-to-blood and tumor-to-muscle ratios were also observed at 24 h after injection. These results suggest that /sup 67/Ga-carrying liposomes may be a useful for tumor imaging.

  1. Tumor uptake of 67Ga-carrying liposomes

    International Nuclear Information System (INIS)

    Ogihara, Izumi; Kojima, Shuji; Kubodera, Akiko; Jay, M.

    1986-01-01

    The in vivo distribution, excretion, and tumor localization of liposome-encapsulated 67 Ga in normal and Ehrlich tumor (solid form)-bearing mice were studied. In normal mice, multilamellar vesicles (MLVs) were taken up mainly be the liver and spleen, whereas small, unilamellar vesicles (SUVs) exhibited a broader tissue distribution. When 67 Ga was encapsulated in MLVs or SUVs, the excretion of the radiotracer in the urine and feces was less than that observed for free tracer at 72 h after i.v. administration. In tumor-bearing mice, SUVs were formed to accumulate preferentially in tumors. The tumor uptake of neutral, positive, and negative SUVs was 10%-13% of the administered dose per gram of tumor tissue at 24 h after their injection. These values were about three times higher than those found for free 67 Ga-nitrilotriacetic acid trisodium salt (NTA) or 67 Ga-citrate. Significant differences in tumor uptake due to different surface charges of liposomes were not observed. Enhanced tumor-to-blood and tumor-to-muscle ratios were also observed at 24 h after injection. These results suggest that 67 Ga-carrying liposomes may be a useful for tumor imaging. (orig.)

  2. Fatigue Analysis of Load-Carrying Fillet Welds

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Tychsen, Jesper; Andersen, Jens Ulfkjær

    2006-01-01

    The fatigue strength of load-carrying fillet welds is, in most codes of practice, performed neglecting the influence of bending in the weld throat section. However, some commonly applied structural details give rise to significant bending in the weld throat section. An example of such a detail is....... Using the test results, it is shown that the new definition of fatigue stress can be used for a wide range of DOB with a low standard deviation of the resulting SN curve....... is a doubler plate connection, which is often applied in connection with modifications of offshore structures. As a part of the present work, fatigue tests have been performed with test specimens fabricated by the current industry standard for welded offshore steel structures. The fatigue tests show...... that the degree of bending (DOB) has an influence on the fatigue lifetime. The fatigue lifetime decreases significantly when increasing the bending stress. In order to take into account the effect of the bending, a new fatigue stress definition applicable for fillet welds failing through the weld is presented...

  3. Single-electron states near a current-carrying core

    International Nuclear Information System (INIS)

    Masale, M.

    2004-01-01

    The energy spectrum of an electron confined near a current-carrying core is obtained as a function of the azimuthal applied magnetic field within the effective-mass approximation. The double degeneracy of the non-zero electron's axial wave number (k z ) states is lifted by the current-induced magnetic field while that of the non-zero azimuthal quantum number (m) states is preserved. A further analysis is the evaluations of the oscillator strengths for optical transitions involving the lowest-order pair of the electron's energy subbands within the dipole approximation. The radiation field is taken as that of elliptically polarized light incident along the core axis. In this polarization and within the dipole approximation, the allowed transitions are only those governed by the following specific selection rules. The azimuthal quantum numbers of the initial and final states must differ by unity while the electron's axial wave number is conserved. The azimuthal magnetic field is also found to lift the multiple degeneracies of the k z ≠0 interaction integrals as well as those of the oscillator strengths for optical transitions

  4. Roadmap and performance carried out during Ciemat site decommissioning

    International Nuclear Information System (INIS)

    Quinones, Javier; Diaz Diaz, Jose Luis

    2005-01-01

    Ciemat (Research Centre for Energy, Environment and Technology) located in the heart of the Ciudad Universitaria of Madrid, occupies a property of 20 Ha. Since its creation in 1951 as JEN, and in 1986 renowned as Ciemat, it has involved on R and D projects in the field of Energy and Environment, i.e., Nuclear Fission, Nuclear Fusion, Fossils Fuels, Renewable Energy. As a consequence of the R and D projects developed between 1951 - 1986 on Nuclear Fission field (fuel design, fabrication, characterization on irradiated fuels, safety studies, etc) and to the diversification of the goals as well, it is necessary to Decommissioning and Dismantling (D and D) from nuclear facilities (nuclear reactor, Hot Cells, Irradiation facility), buildings and soils. Preparations for D and D included a staged shutdown of operations, planning documentation and licensing for decommissioning. As a prerequisite to Ciemat application for a decommissioning license and nuclear environmental assessment was carried out according to Spanish Nuclear Council (CSN) and approval of the site decommissioning project was obtained in 2000 and valid until December 31, 2006. Since 2001 - 2003 is underway and focussed on the radiological characterization of the site (divided in pieces of ground), when each piece of ground is characterized a planning for D and D is presented to CSN in order to obtain a license for actuation. Nowadays several pieces of ground are decontaminated and modifications have been done in order to achieve a safe state of storage-with-surveillance. Later phases have planned waste management improvements for selected wastes already on temporally storage, eventually followed by final decommissioning of facilities and buildings and cleaning of contaminants from soils and removal of waste from the site. This paper describes the planning, nuclear and environment assessment and descriptions of decommissioning activities currently underway at Ciemat. (Author)

  5. Estimating landscape carrying capacity through maximum clique analysis

    Science.gov (United States)

    Donovan, Therese; Warrington, Greg; Schwenk, W. Scott; Dinitz, Jeffrey H.

    2012-01-01

    Habitat suitability (HS) maps are widely used tools in wildlife science and establish a link between wildlife populations and landscape pattern. Although HS maps spatially depict the distribution of optimal resources for a species, they do not reveal the population size a landscape is capable of supporting--information that is often crucial for decision makers and managers. We used a new approach, "maximum clique analysis," to demonstrate how HS maps for territorial species can be used to estimate the carrying capacity, N(k), of a given landscape. We estimated the N(k) of Ovenbirds (Seiurus aurocapillus) and bobcats (Lynx rufus) in an 1153-km2 study area in Vermont, USA. These two species were selected to highlight different approaches in building an HS map as well as computational challenges that can arise in a maximum clique analysis. We derived 30-m2 HS maps for each species via occupancy modeling (Ovenbird) and by resource utilization modeling (bobcats). For each species, we then identified all pixel locations on the map (points) that had sufficient resources in the surrounding area to maintain a home range (termed a "pseudo-home range"). These locations were converted to a mathematical graph, where any two points were linked if two pseudo-home ranges could exist on the landscape without violating territory boundaries. We used the program Cliquer to find the maximum clique of each graph. The resulting estimates of N(k) = 236 Ovenbirds and N(k) = 42 female bobcats were sensitive to different assumptions and model inputs. Estimates of N(k) via alternative, ad hoc methods were 1.4 to > 30 times greater than the maximum clique estimate, suggesting that the alternative results may be upwardly biased. The maximum clique analysis was computationally intensive but could handle problems with < 1500 total pseudo-home ranges (points). Given present computational constraints, it is best suited for species that occur in clustered distributions (where the problem can be

  6. Detección de Rickettsia spp. en ectoparásitos de animales domésticos y silvestres de la Reserva Natural Privada Cerro Chucantí y comunidades aledañas, Panamá, 2007-2010

    Directory of Open Access Journals (Sweden)

    Sergio Bermúdez

    2012-06-01

    Full Text Available Introducción. Los ectoparásitos son los principales vectores de rickettsiosis. En Panamá se tienen escasos datos sobre los artrópodos que pudieran considerarse vectores o reservorios. Objetivos. Presentar datos sobre la presencia de Rickettsia spp. en ectoparásitos de fauna silvestre y animales domésticos en la Reserva Natural Privada Cerro Chucantí y poblados vecinos. Materiales y métodos. Se revisaron 9 personas, 95 mamíferos domésticos y 48 silvestres. Los animales domésticos se examinaron con anuencia del propietario, mientras que la fauna silvestre se capturó con trampas Sherman y Tomahawk. Se extrajeron 21 especies de ectoparásitos: pulgas, piojos, garrapatas y otros ácaros, los cuales se preservaron en etanol al 95 %. Se extrajo material genético de garrapatas y pulgas para ser analizado por técnicas moleculares en la detección de Rickettsia spp. Resultados. Se practicaron 425 reacciones de PCR, de las cuales, 270 resultaron negativas y 155 positivas. De las positivas, 86 amplificaron para el gen gltA (55 % de las positivas; de estos también amplificaron 41 (26 % para ompA. Se encontró material genético de Rickettsia amblyommii, en garrapatas de caballos (Amblyomma cajennense, Dermacentor nitens, de perros (Rhipicephalus sanguineus y ninfas de Amblyomma recolectadas en el bosque. Además, se detectó ADN de R. felis en pulgas Ctenocephalides felis de perros. Conclusiones. Se pudo detectar la presencia de R. amblyommii y R. felis en garrapatas y pulgas de animales domésticos de los poblados cercanos a Cerro Chucantí, aun cuando no se pudo encontrar material genético de Rickettsia en ectoparásitos de la fauna silvestre.   doi: http://dx.doi.org/10.7705/biomedica.v32i2.390

  7. Seroprevalencia de la infección por Borrelia burgdorgferi y Rickettsia conorii en población humana y canina de la zona básica de salud de San Andrés del Rabanedo (León, España)

    OpenAIRE

    Rojo Vázquez Jaime

    1997-01-01

    FUNDAMENTOS: Se estudia la seroprevalencia de la infección por Borrelia burgdorferi y Rickettsia conorii en población humana y canina para conocer la situación de ambas en humanos, al mismo tiempo que la significación del perro, como indicador de la circulación de estos agentes entre aquéllos, en la Zona de Salud de San Andrés del Rabanedo, León. MÉTODO: Se realizó un estudio en 98 sueros humanos y 95 caninos (de diversas razas y aptitudes) frente a B. burgdorferi (títulos de positividad > a ...

  8. Detección de Rickettsia spp. en ectoparásitos de animales domésticos y silvestres de la Reserva Natural Privada Cerro Chucantí y comunidades aledañas, Panamá, 2007-2010

    OpenAIRE

    Sergio Bermúdez; Roberto Miranda; Yamitzel Zaldívar; Publio González; Guido Berguido; Diomedes Trejos; Juan M. Pascale; Marcelo Labruna

    2012-01-01

    Introducción. Los ectoparásitos son los principales vectores de rickettsiosis. En Panamá se tienen escasos datos sobre los artrópodos que pudieran considerarse vectores o reservorios. Objetivos. Presentar datos sobre la presencia de Rickettsia spp. en ectoparásitos de fauna silvestre y animales domésticos en la Reserva Natural Privada Cerro Chucantí y poblados vecinos. Materiales y métodos. Se revisaron 9 personas, 95 mamíferos domésticos y 48 silvestres. Los animales domésticos se ex...

  9. Tensorial spacetime geometries carrying predictive, interpretable and quantizable matter dynamics

    International Nuclear Information System (INIS)

    Rivera Hernandez, Sergio

    2012-01-01

    Which tensor fields G on a smooth manifold M can serve as a spacetime structure? In the first part of this thesis, it is found that only a severely restricted class of tensor fields can provide classical spacetime geometries, namely those that can carry predictive, interpretable and quantizable matter dynamics. The obvious dependence of this characterization of admissible tensorial spacetime geometries on specific matter is not a weakness, but rather presents an insight: it was Maxwell theory that justified Einstein to promote Lorentzian manifolds to the status of a spacetime geometry. Any matter that does not mimick the structure of Maxwell theory, will force us to choose another geometry on which the matter dynamics of interest are predictive, interpretable and quantizable. These three physical conditions on matter impose three corresponding algebraic conditions on the totally symmetric contravariant coefficient tensor field P that determines the principal symbol of the matter field equations in terms of the geometric tensor G: the tensor field P must be hyperbolic, time-orientable and energy-distinguishing. Remarkably, these physically necessary conditions on the geometry are mathematically already sufficient to realize all kinematical constructions familiar from Lorentzian geometry, for precisely the same structural reasons. This we were able to show employing a subtle interplay of convex analysis, the theory of partial differential equations and real algebraic geometry. In the second part of this thesis, we then explore general properties of any hyperbolic, time-orientable and energy-distinguishing tensorial geometry. Physically most important are the construction of freely falling non-rotating laboratories, the appearance of admissible modified dispersion relations to particular observers, and the identification of a mechanism that explains why massive particles that are faster than some massless particles can radiate off energy until they are slower than all

  10. Tensorial spacetime geometries carrying predictive, interpretable and quantizable matter dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Rivera Hernandez, Sergio

    2012-02-15

    Which tensor fields G on a smooth manifold M can serve as a spacetime structure? In the first part of this thesis, it is found that only a severely restricted class of tensor fields can provide classical spacetime geometries, namely those that can carry predictive, interpretable and quantizable matter dynamics. The obvious dependence of this characterization of admissible tensorial spacetime geometries on specific matter is not a weakness, but rather presents an insight: it was Maxwell theory that justified Einstein to promote Lorentzian manifolds to the status of a spacetime geometry. Any matter that does not mimick the structure of Maxwell theory, will force us to choose another geometry on which the matter dynamics of interest are predictive, interpretable and quantizable. These three physical conditions on matter impose three corresponding algebraic conditions on the totally symmetric contravariant coefficient tensor field P that determines the principal symbol of the matter field equations in terms of the geometric tensor G: the tensor field P must be hyperbolic, time-orientable and energy-distinguishing. Remarkably, these physically necessary conditions on the geometry are mathematically already sufficient to realize all kinematical constructions familiar from Lorentzian geometry, for precisely the same structural reasons. This we were able to show employing a subtle interplay of convex analysis, the theory of partial differential equations and real algebraic geometry. In the second part of this thesis, we then explore general properties of any hyperbolic, time-orientable and energy-distinguishing tensorial geometry. Physically most important are the construction of freely falling non-rotating laboratories, the appearance of admissible modified dispersion relations to particular observers, and the identification of a mechanism that explains why massive particles that are faster than some massless particles can radiate off energy until they are slower than all

  11. Pesquisa de anticorpos anti-Rickettsia rickettsii em eqüinos do Centro de Controle de Zoonoses do município de São Paulo (CCZ/SP

    Directory of Open Access Journals (Sweden)

    Jonas Moraes-Filho

    2009-04-01

    Full Text Available A Febre Maculosa Brasileira (FMB é uma zoonose transmitida por pelo menos duas espécies de carrapatos: Amblyomma cajennense e Amblyomma aureolatum. Os eqüinos assumem um importante papel de sentinela da FMB em áreas onde o carrapato vetor é o A. cajennense, por ser considerado hospedeiro primário dessa espécie de carrapato. O A. aureolatum, cujos hospedeiros primários são aves, alguns roedores silvestres e canídeos, é incriminado como vetor da doença na região da Grande São Paulo. Este trabalho objetivou pesquisar a presença de anticorpos contra Rickettsia rickettsii, agente da FMB, em eqüinos encaminhados ao Centro de Controle de Zoonoses do município de São Paulo (CCZ/SP no período de 2003 a 2005. Após coleta de sangue, o soro obtido pela centrifugação foi submetido à reação de imunofluorescência indireta (RIFI e os animais foram considerados positivos quando as amostras de soro apresentaram títulos >; 64. Durante os três anos, foram testados 363 amostras pela RIFI, sendo que 64 se mostraram reagentes: 6 (2003, 16 (2004 e 42 (2005. Os títulos finais variaram de 64 a 1.024. Os resultados obtidos demonstram uma baixa porcentagem de animais reagentes (17,6% quando comparados com dados de literatura de áreas endêmicas para FMB onde o vetor é o A. cajennense, sugerindo não ser essa espécie responsável pela transmissão da doença na área de estudo

  12. Cytotoxic effector functions of T cells are not required for protective immunity against fatal Rickettsia typhi infection in a murine model of infection: Role of TH1 and TH17 cytokines in protection and pathology.

    Directory of Open Access Journals (Sweden)

    Kristin Moderzynski

    2017-02-01

    Full Text Available Endemic typhus caused by Rickettsia (R. typhi is an emerging febrile disease that can be fatal due to multiple organ pathology. Here we analyzed the requirements for protection against R. typhi by T cells in the CB17 SCID model of infection. BALB/c wild-type mice generate CD4+ TH1 and cytotoxic CD8+ T cells both of which are sporadically reactivated in persistent infection. Either adoptively transferred CD8+ or CD4+ T cells protected R. typhi-infected CB17 SCID mice from death and provided long-term control. CD8+ T cells lacking either IFNγ or Perforin were still protective, demonstrating that the cytotoxic function of CD8+ T cells is not essential for protection. Immune wild-type CD4+ T cells produced high amounts of IFNγ, induced the release of nitric oxide in R. typhi-infected macrophages and inhibited bacterial growth in vitro via IFNγ and TNFα. However, adoptive transfer of CD4+IFNγ-/- T cells still protected 30-90% of R. typhi-infected CB17 SCID mice. These cells acquired a TH17 phenotype, producing high amounts of IL-17A and IL-22 in addition to TNFα, and inhibited bacterial growth in vitro. Surprisingly, the neutralization of either TNFα or IL-17A in CD4+IFNγ-/- T cell recipient mice did not alter bacterial elimination by these cells in vivo, led to faster recovery and enhanced survival compared to isotype-treated animals. Thus, collectively these data show that although CD4+ TH1 cells are clearly efficient in protection against R. typhi, CD4+ TH17 cells are similarly protective if the harmful effects of combined production of TNFα and IL-17A can be inhibited.

  13. [Ecotourism carrying capacity of Hangzhou Xixi National Wetland Park in China].

    Science.gov (United States)

    Li, Rui; Rong, Liang

    2007-10-01

    In this paper, an integrated estimation on the ecotourism carrying capacity of Hangzhou Xixi National Wetland Park in China was made from the aspects of ecological carrying capacity, spatial carrying capacity, facility carrying capacity, management carrying capacity, and psychological carrying capacity. The results indicated that the tourism carrying capacity of the Park was 4 145 - 6 450 persons per day. The rational distance between man and bird was first adopted to determine the ecotourism carrying capacity of wetland, which provided an effective solution both to fully ensure bird safety and to appropriately develop wetland tourism. The estimation of psychological carrying capacity based on tourist satisfaction degree reflected more objectively the extent the tourist demands satisfied at the planning, construction and management of tour places. Such an integrated estimation method based on the distance between man and bird and the tourist satisfaction degree could be of practical and instructive significances in the planning and management of wetland parks.

  14. Circulação de Rickettsias do Grupo da Febre Maculosa em cães no entorno de Unidades de Conservação Federais do estado do Rio de Janeiro: evidência sorológica e fatores associados

    Directory of Open Access Journals (Sweden)

    Sabrina D.E. Campos

    Full Text Available RESUMO: Doenças causadas por rickettsias tem ampla distribuição geográfica e estão associadas a artrópodes hematófagos. Rickettsia rickettsii é espécie mais patogênica do Grupo da Febre Maculosa (GFM e responsável pela Febre Maculosa Brasileira. No sudeste do país a doença é endêmica e inquéritos sorológicos tem demonstrado presença de anticorpos para antígenos do GFM em cães, reforçando a participação do cão como sentinela. Os principais vetores são carrapatos do gênero Amblyomma, cujos hospedeiros são, muitas vezes, animais de vida silvestre. Assim, objetivou-se avaliar a circulação de rickettsias do GFM no entorno de Unidades de Conservação (UC no Rio de Janeiro por meio da Imunofluorescência Indireta em cães, além de determinar os fatores associados. Amostras de soro de 155 cães foram testadas, sendo 16,1% dos animais sororreagentes pelo menos a um dos antígenos testados. Houve associação entre a sororreatividade dos cães e o acesso à mata; falta de assistência médico-veterinária; falta de medidas contra carrapatos; e renda familiar do responsável de até dois salários mínimos. Cães com este perfil apresentaram maior chance de serem expostos aos agentes do GFM. De acordo com o modelo de regressão logística, não frequentar áreas de mata foi considerado um fator de proteção para o cão, juntamente com possuir acompanhamento médico-veterinário e receber medidas contra carrapatos. Concluiu-se que patógenos do GFM circulam no entorno das UC estudadas, sendo possível que R. rickettsii e R. parkeri infectem cães, uma vez que os animais demonstraram exposição aos dois agentes. Ressalta-se a participação do veterinário e a adoção de medidas de combate a carrapatos como ferramentas na prevenção da infecção rickettsial.

  15. Moment of the Legal Termination of the Organization and/or Carrying out Gambling Which is Carried Out in the Information Communication Network Internet

    Directory of Open Access Journals (Sweden)

    Boris R. Avetisyan

    2016-03-01

    Full Text Available Both for the legal doctrine, and for law enforcement the category "moment of the termination of a crime" is determined by the general concept of the moment of legal completion of criminal encroachment. In article the content of this category for the organization and carrying out the gamblings which are carried out on the Internet is specified. In the conclusion author concluds that the moment of the termination of the organization and carrying out gamblings out of a gambling zone should be regarded as an independent objective sign.

  16. Sdelki carry trade ne roskosh, a sredstvo nakoplenija / Darius Gecevicius, Dmitri Fokin

    Index Scriptorium Estoniae

    Gecevicius, Darius

    2007-01-01

    Strateegia carry trade kasutamisest valuutaturgudel. Carry trade on tehing, mis enamasti toimub valuutaturul, kus investor laenab raha sisse valuutas, mille intressid on madalamad ning paigutab selle valuutas, kus intressid on kõrgemad. Diagramm

  17. Free vibrations of a multi-span Timoshenko beam carrying multiple ...

    Indian Academy of Sciences (India)

    The literature regarding the free vibration analysis of Bernoulli–Euler single-span beams carrying a number of spring-mass system and Bernoulli–Euler multi-span beams carrying multiple spring-mass systems are plenty, but on Timoshenko multi-span beams carrying multiple spring-mass systems is fewer. This paper aims ...

  18. 36 CFR 1005.4 - Commercial passenger-carrying motor vehicles.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Commercial passenger-carrying motor vehicles. 1005.4 Section 1005.4 Parks, Forests, and Public Property PRESIDIO TRUST COMMERCIAL AND PRIVATE OPERATIONS § 1005.4 Commercial passenger-carrying motor vehicles. Passenger-carrying motor...

  19. 46 CFR 25.45-2 - Cooking systems on vessels carrying passengers for hire.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Cooking systems on vessels carrying passengers for hire... REQUIREMENTS Cooking, Heating, and Lighting Systems § 25.45-2 Cooking systems on vessels carrying passengers for hire. (a) No fuel may be used in any cooking system on any vessel carrying passengers for hire...

  20. 25 CFR 161.204 - How are carrying capacities and stocking rates established?

    Science.gov (United States)

    2010-04-01

    ... WATER NAVAJO PARTITIONED LANDS GRAZING PERMITS General Provisions § 161.204 How are carrying capacities... on each range or management unit. (c) BIA will review the carrying capacity of the grazing units on a... 25 Indians 1 2010-04-01 2010-04-01 false How are carrying capacities and stocking rates...

  1. The energetic costs of load-carrying and the evolution of bipedalism.

    Science.gov (United States)

    Watson, J C; Payne, R C; Chamberlain, A T; Jones, R K; Sellers, W I

    2008-05-01

    The evolution of habitual bipedalism is still a fundamental yet unsolved question for paleoanthropologists, and carrying is popular as an explanation for both the early adoption of upright walking and as a positive selection pressure once a terrestrial lifestyle had been adopted. However, to support or reject any hypothesis that suggests carrying efficiency was an important selective pressure, we need quantitative data on the costs of different forms of carrying behavior, especially infant-carrying since reduction in the grasping capabilities of the foot would have prevented infants from clinging on for long durations. In this study, we tested the hypothesis that the mode of load carriage influences the energetic cost of locomotion. Oxygen consumption was measured in seven female participants walking at a constant speed while carrying four different 10-kg loads (a weighted vest, 5-kg dumbbells carried in each hand, a mannequin infant carried on one hip, and a 10-kg dumbbell carried in a single hand). Oxygen consumption was also measured during unloaded standing and unloaded walking. The results show that the weighted vest requires the least amount of energy of the four types of carrying and that, for this condition, humans are as efficient as mammals in general. The balanced load was carried with approximately the predicted energy cost. However, the asymmetrical conditions were considerably less efficient, indicating that, unless infant-carrying was the adaptive response to a strong environmental selection pressure, this behavior is unlikely to have been the precursor to the evolution of bipedalism.

  2. Literature review on land carrying capacity of the coordinated development of population, resources, environment and economy

    Science.gov (United States)

    Ma, Biao

    2017-10-01

    Land carrying capacity is an important index of evaluation on land resources. And the land carrying capacity is also very important for guiding regional plans and promoting sustainable development of regional economy. So it is significant to clarify the land carrying capacity in the sequence of events which helps the decision makers understand and grasp the knowledge of land carrying capacity more clearly and make the right judgment and decision. Based on the theory of population, resources, environment and economy, the method of reviewing literatures is used in this paper to summarize the theory of the land carrying capacity and the researching methods of the land carrying capacity, as well as the problems existing in the study of land carrying capacity.

  3. Emergence of Klebsiella pneumoniae ST273 Carrying blaNDM-7and ST656 Carrying blaNDM-1in Manila, Philippines.

    Science.gov (United States)

    Chou, Andrew; Roa, Marylette; Evangelista, Michael A; Sulit, Arielle Kae; Lagamayo, Evelina; Torres, Brian C; Klinzing, David C; Daroy, Maria Luisa G; Navoa-Ng, Josephine; Sucgang, Richard; Zechiedrich, Lynn

    2016-10-01

    We sought to determine the epidemiology of carbapenem-resistant Enterobacteriaceae and to investigate the emergence of carbapenem-resistant Klebsiella pneumoniae in two teaching hospitals in Manila, Philippines. We screened 364 Enterobacteriaceae for carbapenem resistance between 2012 and 2013 and detected four carbapenem-resistant K. pneumoniae isolates from three different patients. We used whole genome sequencing to determine the antibiotic resistance profiles and confirmed the presence of carbapenemase genes by multiplex PCR. We used multilocus sequence typing and PCR-based replicon typing to genetically characterize the carbapenem-resistant isolates. The carbapenemase gene bla NDM was detected in K. pneumoniae isolates from two patients. The first patient had ventilator-associated pneumonia and lumbar shunt infection from K. pneumoniae ST273 carrying bla NDM-7 . The second patient had asymptomatic genitourinary colonization with K. pneumoniae ST656 carrying bla NDM-1 . The third patient had a gluteal abscess with K. pneumoniae ST1 that did not carry a carbapenemase gene, but did carry bla DHA-1 , bla OXA-1 , and bla SHV-1 . In this study, we report the first cases of bla NDM -carrying pathogens in the Philippines and add to the growing evidence of the worldwide spread of ST273 and NDM-7, a more efficient carbapenem hydrolyzer than NDM-1.

  4. Estimating Recreational Carrying Capacity of Gheisary Protected Area in Chaharmahal & Bakhtiari Province

    Directory of Open Access Journals (Sweden)

    A. Sheikh

    2014-03-01

    Full Text Available It is now certain that to ensure a long term sustainable development, protected areas, the favored destinations for ecotourism, required a well written planning management. Each destination however has limited capability which is called “carrying capacity” to invite visitors. Physical, real (ecological and effective (manageable are different kinds of carrying capacity. The current study presented these varieties of carrying capacities for Gheisary protected area, stretched over 10,000 ha in Cheharmahal- & Bakhtiary province. The physical carrying capacity was measured using an ecotourism-based zoning followed by imposing periodic, pedologic, climatic and vegetative limitations, based on the minimum area needed for each person. Real carrying capacity was then calculated according to the physical carrying capacity. The results showed that the intensive recreation zone with surface of 1,292 ha had the annual physical carrying capacity of 2,079,227 and real carrying capacity of 18,465 people. The values for the extensive recreation zone with surface of 2,378 ha were 2,478,832 and 1,215 respectively. The study has also speculated the embedded management strength and recreation convenience of the area and concluded that effective carrying capacity can only enjoy 10% of the real carrying capacity, which were 1,968 people.

  5. Pathogenesis of Cell Injury by Rickettsia conorii

    Science.gov (United States)

    1986-11-26

    This is also one explanation for the scarcity of information about the prevalence of the disease. The low endemicity that prevails in the majority...Ixodes granulatus in Malaysia ; Rhipicephalus simus, Antlyomma variegatum, A. cohaeren, ’and A. gemma in Ethiopia; and. Rhipicephalus bursa, Hyalomma...reported in France, South’Africa, Israel, Spain, Belglum, and Portugal. Old age, alcohol ism diabetes , male sex, and gl ucose-6-phosphate dehydrogenase

  6. Rickettsia rickettsii isolation from naturally infected Amblyomma ...

    African Journals Online (AJOL)

    . rickettsii) and is transmitted by the bite of ticks of the genera Dermacentor, Amblyomma and Rhipicephalus. The illness results in a high mortality rate and may be easily confused with other febrile syndromes. In Yucatan State, Mexico, ...

  7. Rickettsiae, protozoa, and opisthokonta/metazoa.

    Science.gov (United States)

    Schmutzhard, Erich; Helbok, Raimund

    2014-01-01

    Rhizobiales (formerly named Rickettsiales) cause in rare instances meningitis and meningovasculitis, respectively. In case of history of exposure, infection by Rhizobiales needs to be considered since both diagnosis and therapy may be extremely difficult and pathogen-specific. The same applies to protozoa; in this chapter, Babesia species, free-living amoebae and Entamoeba histolytica infection, including severe meningitis and brain abscess, infection by Trypanosoma species (South American and African trypanosomiasis) are discussed with respect to history, epidemiology, clinical signs, and symptoms as well as differential diagnosis and therapy. Parasitic flatworms and roundworms, potentially able to invade the central nervous system, trematodes (flukes), cestodes (in particular, Cysticercus cellulosae), but also nematodes (in particular, Strongyloides spp. in the immunocompromised) are of worldwide importance. In contrast, filarial worms, Toxocara spp., Trichinella spp., Gnathostoma and Angiostrongylus spp. are seen only in certain geographically confined areas. Even more regionally confined are infestations of the central nervous system by metazoa, in particular, tongue worms (=arthropods) or larvae of flies (=maggots). The aim of this chapter is (1) to alert the neurologist to these infections, and (2) to enable the attending emergency neurologist to take a knowledgeable history, with an emphasis on epidemiology, clinical signs, and symptoms as well as therapeutic management possibilities. © 2014 Elsevier B.V. All rights reserved.

  8. Pathogenesis of Cell Injury by Rickettsia conorii

    Science.gov (United States)

    1985-05-17

    from our laboratory. It documented rickettsial vascular lesions of vasculitis or thrombosis in stomach in 89% of the cases, in the small intestine in all...cases, in the large intestine in 92%, and In the pancreas of 70%. Although it is possible 4 for rickettsial vasculitis to result in gastrointestinal...conorii Clin. Microbiot .. I1: 503-507. 4. Parker, R. T.. Menon, G. P.. Merideth, A. M., in the IgG class than in tht IgM class, as would Snyder. M. G

  9. Human Infection with Rickettsia felis, Kenya

    Science.gov (United States)

    2010-07-01

    Prescribed by ANSI Std Z39-18 RESEARCH rickeltsiosis, brucellosis . leptospirosis, and other viral in- fections. The study protocol was approved by the...province hns an averag..: annual rainfall ម mm; is inhabited by a predominantly seminomadic pastora list population of So- ma li origin who keep cattle ...contact with livestock animals such as cattle , sheep, goats, or camels. Although this was not captured in the question- naire, almost all livestock

  10. Kinetic characteristics of the gait of a musician carrying or not his instrument

    Directory of Open Access Journals (Sweden)

    Carlos Bolli Mota

    2009-01-01

    Full Text Available The integrity of the locomotor system can be compromised by the transport of certain objects, especially when done in an inadequate manner. Due to their weight and size, the transport of musical instruments can contribute to body dysfunctions in musicians who frequently have to carry their instruments, influencing balance andbody posture. Thus, the soil reaction force was investigated during the gait of a musician carrying or not his instrument. Two AMTI (Advanced Mechanical Technologies, Inc. platforms were used for kinetic data acquisition. A total of 40 measurements were obtainedfor gait and balance: 20 without carrying the instrument and 20 while carrying the instrument. The t test showed significant differences between the two situations for all variables analyzed. The results suggest that the locomotor system suffers alterationswhen carrying any kind of load, as was the case here in which the subject carried 7.75% of his own weight.

  11. A model to estimate aquaculture carrying capacity in three areas of the Philippines

    Directory of Open Access Journals (Sweden)

    Tarzan Legović

    2008-12-01

    Full Text Available A model was developed to estimate the production carrying capacity of water bodies based on nutrient inputs from aquaculture and other sources, flushing rates, and the risk of algal blooms for three different areas of the Philippines – Bolinao (marine site, Dagupan (brackishwater site and Taal Lake (freshwater site. The results suggest that aquaculture production in the Taal Lake was greater than the sustainable carrying capacity. Aquaculture structures in Bolinao were close to carrying capacity during average tidal exchange but greater than the carrying capacity during low tidal exchange and no winds.Aquaculture production in the Dagupan estuary has not overcome its carrying capacity even during low flow. However, during very low flow and no tidal flushing, carrying capacity has been overcome.

  12. Evaluation of Ecological Carrying Capacity of Henan Province under the Sustainable Development

    OpenAIRE

    Jiang, Xiao-ping

    2010-01-01

    Based on the overview of social economy of Henan Province, I probe into the concept and evaluation of ecological carrying capacity. By using the ecological footprint analysis and the data of various kinds of land supply of Henan Province from 2000 to 2008, the ecological carrying capacity of Henan Province is analyzed. It is unveiled that inharmonious population, natural resources and economic resources affects the efficiency of the sustainable development of ecological carrying capacity of H...

  13. Concept and Connotation of Water Resources Carrying Capacity in Water Ecological Civilization Construction

    Science.gov (United States)

    Chao, Zhilong; Song, Xiaoyu; Feng, Xianghua

    2018-01-01

    Water ecological civilization construction is based on the water resources carrying capacity, guided by the sustainable development concept, adhered to the human-water harmony thoughts. This paper has comprehensive analyzed the concept and characteristics of the carrying capacity of water resources in the water ecological civilization construction, and discussed the research methods and evaluation index system of water carrying capacity in the water ecological civilization construction, finally pointed out that the problems and solutions of water carrying capacity in the water ecological civilization construction and put forward the future research prospect.

  14. New insights in the role of working memory in carry and borrow operations

    Directory of Open Access Journals (Sweden)

    Ineke Imbo

    2005-06-01

    Full Text Available The present paper provides a state-of-the-art overview concerning the role of working memory in carry and borrow operations in mental arithmetic. The role of the executive working-memory component is discussed, alongside the contribution of the phonological and visuo-spatial working-memory components. Moreover, a broad view on various carry characteristics (such as the number of carry/borrow operations and the value of the carry and various operations (addition, subtraction, and multiplication is provided. Finally, some ideas for further research are offered.

  15. Modeling of predictive muscular strength for sustained one-handed carrying task.

    Science.gov (United States)

    Li, Kai Way; Wang, Chien Wen; Yu, Ruifeng

    2015-01-01

    Manual materials handling (MMH) tasks are common. They are considered major contributors of musculoskeletal injuries and are the sources of financial burden for industries in terms of lost work days and worker compensation costs. One-handed carrying is common and could result in arm fatigue. The purpose of this study was to establish predictive models for one-handed carrying strength considering weight handed and handedness conditions. Twenty male subjects were recruited for the study. The subject carried a weight of 6 or 12 kg using either dominant or non-dominant hand lasting a time period of 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, or 4 minutes. The results showed that handedness (p carrying strength. Predictive models of single arm carrying strength were established under handedness and weight conditions. The MADs of these models ranged from 0.39 to 2.19 kgf. The exponential function based predictive models may be adopted to describe the single arm carrying strength with reasonable predictive errors. The trend of the carrying strength after carrying a load for a certain period may be employed to describe muscular fatigue for sustained carrying tasks.

  16. Specifying the Role of Exposure to Violence and Violent Behavior on Initiation of Gun Carrying: A Longitudinal Test of Three Models of Youth Gun Carrying

    Science.gov (United States)

    Spano, Richard; Pridemore, William Alex; Bolland, John

    2012-01-01

    Two waves of longitudinal data from 1,049 African American youth living in extreme poverty are used to examine the impact of exposure to violence (Time 1) and violent behavior (Time 1) on first time gun carrying (Time 2). Multivariate logistic regression results indicate that (a) violent behavior (Time 1) increased the likelihood of initiation of…

  17. Elemental content of the placenta: A comparison between two high-risk obstetrical populations, adult women carrying multiples and adolescents carrying singletons.

    Science.gov (United States)

    de Angelis, Paolo; Miller, Richard K; Darrah, Thomas H; Katzman, Philip J; Pressman, Eva K; Kent, Tera R; O'Brien, Kimberly O

    2017-10-01

    The placenta is responsible for the exchange of nutrients and for preventing harmful compounds from entering the fetal circulation. With increasing industrialization, exposures to commercial and toxic metals become a concern for both pregnant women and those planning a pregnancy. The understanding of transport mechanisms and pharmacokinetics for most inorganic elements is incomplete and limited to normal term deliveries. To obtain novel data on 46 inorganic elements in placentae from two high-risk obstetric populations, women carrying multiples and adolescents carrying singletons, evaluating differences, if present, and identifying predictors of placental content. Placental tissue was collected from adolescents carrying singletons and adults carrying multiples. Elemental content was analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). Multivariate regression and factor analyses were used. With the exception of Au and Pt, almost all placentae contained quantifiable concentrations of each element analyzed. All placentae contained the essential elements Ca, Fe, Mg, Se and Zn, which clustered together onto the same factor. Most elements were higher in placentae from women carrying multiples. Differences in placental content disappeared after adjusting for maternal age. Rare earth elements (REEs) clustered together and remained higher in the multiples even after adjusting for maternal age. Human placentae contain a wide range of elements, including REEs. Ranges differed considerably between cohorts. Elements with similar chemical properties, like REEs or nutritionally essential elements, clustered together. Maternal age, and therefore longer environmental exposure, was significantly associated with elevated element concentrations in the placenta. Placental concentrations of several metals that are known to be nutritionally essential (e.g., Fe, Ca, Mg, and Zn) did not differ significantly between cohorts, suggesting tight regulation, whereas

  18. Carry A. Nation: "The Famous and Original Bar Room Smasher" Curriculum Packet.

    Science.gov (United States)

    Kansas State Historical Society, Topeka.

    Carry Nation's personality, religious beliefs, and marriages to Charles Gloyd and, after his death, to David Nation all formed her into the reformer for which she became known. Carry Nation was involved in a variety of reform causes including prohibition, anti-smoking, women's health, and suffrage. Her prohibition reform efforts took place after…

  19. 75 FR 17313 - Temporary Assistance for Needy Families (TANF) Carry-Over Funds

    Science.gov (United States)

    2010-04-06

    ... RIN 0970-AC40 Temporary Assistance for Needy Families (TANF) Carry-Over Funds AGENCY: Administration.... SUMMARY: This final rule implements the statutory change to section 404(e) of the Social Security Act as... Territories to use Temporary Assistance for Needy Families (TANF) program funds carried over from a prior year...

  20. Examining Adolescent Suicidal Behaviors in Relation to Gun Carrying and Bullying

    Science.gov (United States)

    Romero, Andrea; Bauman, Sheri; Ritter, Marissa; Anand, Payal

    2017-01-01

    Guided by the interpersonal theory of suicide, this study examines the associations between gun carrying, bullying, and suicidal behaviors among high school students. Arizona Youth Risk Behavior Surveys were completed by 2,677 students in 2011; 9.0% reported suicide attempt in the past year, 5.5% carried a gun in the past 30 days, 8.5% were…

  1. Neutralization of bactericidal activity related to antimicrobial carry-over in broiler carcass rinse samples

    Science.gov (United States)

    Chemical antimicrobial interventions used as poultry processing aids may have potential for carry-over into whole poultry carcass buffered peptone water (BPW) rinses collected for the recovery of viable Salmonella. Such carry-over may lead to false negative indications due to continuing bactericidal...

  2. 46 CFR 25.45-1 - Heating and lighting systems on vessels carrying passengers for hire.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Heating and lighting systems on vessels carrying... UNINSPECTED VESSELS REQUIREMENTS Cooking, Heating, and Lighting Systems § 25.45-1 Heating and lighting systems on vessels carrying passengers for hire. (a) No fuel may be used in any heating or lighting system on...

  3. 42 CFR 71.56 - African rodents and other animals that may carry the monkeypox virus.

    Science.gov (United States)

    2010-10-01

    ... the monkeypox virus. 71.56 Section 71.56 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND... and other animals that may carry the monkeypox virus. (a) What actions are prohibited? What animals... transmitting or carrying the monkeypox virus. Such products include, but are not limited to, fully taxidermied...

  4. Energetic cost of carrying loads: have African women discovered an economic way?

    Science.gov (United States)

    Maloiy, G M; Heglund, N C; Prager, L M; Cavagna, G A; Taylor, C R

    When travelling in East Africa one is often surprised at the prodigious loads carried by the women of the area. It is not uncommon to see women of the Luo tribe carrying loads equivalent to 70% of their body mass balanced on the top of their heads (Fig. 1). Women of the Kikuyu tribe carry equally large loads supported by a strap across their foreheads; this frequently results in a permanently grooved skull. Recent experiments on running horses, humans, dogs and rats showed that the energy expended in carrying a load increased in direct proportion to the weight of the load for each animal at each speed, that is, carrying a load equal to 20% of body weight increased the rate of energy consumption by 20% (ref. 1). The purpose of the present study was to determine whether these African women use specialized mechanisms for carrying very large loads cheaply. We found that both the Luo and Kikuyu women could carry loads of up to 20% of their body weight without increasing their rate of energy consumption. For heavier loads there was a proportional increase in energy consumption, that is, a 30% load increased energy consumption by 10%, a 40% load by 20% and so on. We suggest that some element of training and/or anatomical change since childhood may allow these women to carry heavy loads economically.

  5. Effects of Sprint Training With or Without Ball Carry in Elite Rugby Players.

    Science.gov (United States)

    Seitz, Laurent B; Barr, Matt; Haff, G Gregory

    2015-09-01

    To compare the effects of sprint training with or without ball carry on the sprint performance of elite rugby league players. Twenty-four elite rugby league players were divided into a ball-carry group (BC; n = 12) and a no-ball-carry group (NBC; n = 12). The players of the BC group were required to catch and carry the ball under 1 arm during each sprint, whereas the NBC group performed sprints without carrying a ball. The 8-wk training intervention took place during the precompetitive phase of the season and consisted of 2 sessions/wk. Sprint performance was measured before and after the training intervention with 40-m linear sprints performed under 2 conditions: with and without ball carry. Split times of 10, 20, and 40 m were recorded for further analysis. A 3-way (group × time × condition) factorial ANOVA was performed to compare changes in sprint performance with and without the ball, before and after the training intervention for both BC and NBC training groups Results: The BC and NBC groups experienced similar improvements in 10-, 20-, and 40-m sprint times and accelerations, regardless of the condition under which the sprint tests were performed (P = .19). Sprint training while carrying a rugby ball is as effective as sprint training without carrying a rugby ball for improving the sprint performance of elite rugby league players.

  6. 46 CFR 98.30-4 - Vessels carrying portable tanks other than MPTs.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Vessels carrying portable tanks other than MPTs. 98.30-4 Section 98.30-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS... Portable Tanks § 98.30-4 Vessels carrying portable tanks other than MPTs. (a) Each portable tank, other...

  7. Gun Cultures or Honor Cultures? Explaining Regional and Race Differences in Weapon Carrying

    Science.gov (United States)

    Felson, Richard B.; Pare, Paul-Philippe

    2010-01-01

    We use the National Violence against Women (and Men) Survey to examine the effects of region and race on the tendency to carry weapons for protection. We find that Southern and Western whites are much more likely than Northern whites to carry guns for self-protection, controlling for their risk of victimization. The difference between Southern and…

  8. Effect of Gun Carrying on Perceptions of Risk Among Adolescent Offenders.

    Science.gov (United States)

    Loughran, Thomas A; Reid, Joan A; Collins, Megan Eileen; Mulvey, Edward P

    2016-02-01

    We observed how perceptions of risks, costs, crime rewards, and violence exposure change as individual gun-carrying behavior changes among high-risk adolescents. We analyzed a longitudinal study (2000-2010) of serious juvenile offenders in Maricopa County, Arizona, or Philadelphia County, Pennsylvania, assessing within-person changes in risk and reward perceptions, and violence exposure as individuals initiated or ceased gun carrying. Despite being associated with heightened exposure to violence, gun carrying was linked to lower perceptions of risks and costs and higher perceived rewards of offending. Gun carrying was not time-stable, as certain individuals both started and stopped carrying during the study. Within-person changes in carrying guns were associated with shifting perceptions of risks, costs, and rewards of crime, and changes in exposure to violence in expected directions. Gun carrying reduces perceptions of risks associated with offending while increasing actual risk of violence exposure. This suggests that there is an important disconnect between perceptions and objective levels of safety among high-risk youths. Gun-carrying decisions may not only be influenced by factors of protection and self-defense, but also by perceptions of risks and reward associated with engaging in crime more generally.

  9. Carrying capacity of the succulent valley bushveld of the eastern Cape

    African Journals Online (AJOL)

    Dense bushveld (high ecological status) had higher overall carrying capacity than open bushveld (low ecological status). Carrying capacity changed considerably depending on annual rainfall and this was complicated because the more degraded the veld the greater the variation. Maximum long-term grass production ...

  10. Free vibrations of a multi-span Timoshenko beam carrying multiple ...

    Indian Academy of Sciences (India)

    natural frequency values and mode shapes for a beam carrying any number of spring masses. Naguleswaran (2002, 2003) obtained the natural frequency values of the beams on up to five resilient supports including ends and carrying several particles by using EBT and obtained a fourth-order determinant equated to zero.

  11. 12 CFR 615.5090 - Reduction in carrying value of collateral.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Reduction in carrying value of collateral. 615... FISCAL AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Collateral § 615.5090 Reduction in carrying value of collateral. When the bank or Farm Credit Administration determines that a loan did not...

  12. 77 FR 59408 - Finding of Equivalence; Alternate Pressure Relief Valve Settings on Certain Vessels Carrying...

    Science.gov (United States)

    2012-09-27

    ... Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) Section VIII with respect to...; Alternate Pressure Relief Valve Settings on Certain Vessels Carrying Liquefied Gases in Bulk AGENCY: Coast...-ENG Policy Letter 04-12, ``Alternative Pressure Relief Valve Settings on Vessels Carrying Liquefied...

  13. 36 CFR 702.8 - Use and carrying of food and beverages in Library buildings.

    Science.gov (United States)

    2010-07-01

    ... CONDUCT ON LIBRARY PREMISES § 702.8 Use and carrying of food and beverages in Library buildings. Consumption of food and beverages in Library buildings is prohibited except at point of purchase or other authorized eating places. Under no circumstances may food or beverages be carried to the bookstacks or other...

  14. 46 CFR 98.25-5 - How anhydrous ammonia may be carried.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false How anhydrous ammonia may be carried. 98.25-5 Section 98... Anhydrous Ammonia in Bulk § 98.25-5 How anhydrous ammonia may be carried. (a) Anhydrous ammonia shall be..., except as otherwise provided in paragraph (b) of this section. (b) When anhydrous ammonia is to be...

  15. Form and Function of Carrying Tools in Traditional and Contemporary Culture

    Directory of Open Access Journals (Sweden)

    Hendriana Werdhaningsih

    2009-07-01

    Full Text Available The Javanese Traditional Carrying Tools are categorized into two kinds based used of materials: anyaman made of woven bamboo or rattan and the other was made of cloth. The Traditional Javanese Carrying Tools that were made of bamboo/ rattan is actually a kind of container with different shapes. The types of goods that were brought was related to the shapes of the containers, demonstrate the type of interactions between the carrier and the goods. The Traditional Carrying Tools made of cloth have the flexibility in terms of being the containers of the carried goods. Selendang is used to carry goods, including the bamboo/ rattan containers and to carry babies. It can be used rumpled and straightened depends on the technical needs of carrying tools preferred by the user. In contemporary culture, the form and design of carrying tools more less construct by fashion and trends besides those practical used. Some product are being 'classic', some other are being 'fad'. Both products, traditional and contemporary have their own style, uniqueness, and own context. Analyzing both in design point of view is important as evaluation process, to finding new problems that will be starting point to create new products. Indonesia is well known for its abundant richness in traditions, which include the culture, the art, and the traditional products. Such treasure of traditions can inspire the development and invention of various kinds of artwork and current products.

  16. Comparative analysis of environmental carrying capacity of the Bohai Sea Rim area in China.

    Science.gov (United States)

    Lin, Lu; Liu, Yi; Chen, Jining; Zhang, Tianzhu; Zeng, Siyu

    2011-11-01

    Environmental carrying capacity is an essential metric for measuring regional sustainability. Although the term "carrying capacity" has been applied for over a century, the concept definition, quantitative methods and comprehensive evaluation remain arguable. This study analyzed the carrying capacity of four environmental elements, including water resources, air, surface water and offshore sea, and integrated them into a comprehensive index to represent overall regional profiles of resources and environment. The method was then applied to thirteen municipalities in the Bohai Sea Rim area, one of the most rapidly developing regions in transition China. The results show that the comprehensive environmental carrying capacity of the municipalities in the south sub-region were largest in 2007, while that of the west municipalities were lowest. The regional economic development exceeded the overall environmental carrying capacity by 36% and the west sub-region area deserves overwhelming attention for future industrial allocation.

  17. Environmental sustainability control by water resources carrying capacity concept: application significance in Indonesia

    Science.gov (United States)

    Djuwansyah, M. R.

    2018-02-01

    This paper reviews the use of Water Resources carrying capacity concept to control environmental sustainability with the particular note for the case in Indonesia. Carrying capacity is a capability measure of an environment or an area to support human and the other lives as well as their activities in a sustainable manner. Recurrently water-related hazards and environmental problems indicate that the environments are exploited over its carrying capacity. Environmental carrying capacity (ECC) assessment includes Land and Water Carrying Capacity analysis of an area, suggested to always refer to the dimension of the related watershed as an incorporated hydrologic unit on the basis of resources availability estimation. Many countries use this measure to forecast the future sustainability of regional development based on water availability. Direct water Resource Carrying Capacity (WRCC) assessment involves population number determination together with their activities could be supported by available water, whereas indirect WRCC assessment comprises the analysis of supply-demand balance status of water. Water resource limits primarily environmental carrying capacity rather than the land resource since land capability constraints are easier. WRCC is a crucial factor known to control land and water resource utilization, particularly in a growing densely populated area. Even though capability of water resources is relatively perpetual, the utilization pattern of these resources may change by socio-economic and cultural technology level of the users, because of which WRCC should be evaluated periodically to maintain usage sustainability of water resource and environment.

  18. Estimation of carrying angle based on CT images in preoperative surgical planning for cubitus deformities.

    Science.gov (United States)

    Park, Shinsuk; Kim, Eugene

    2009-12-01

    Conventionally, the carrying angle of the elbow is measured using simple two-dimensional radiography or goniometry, which has questionable reliability. This study proposes a novel method for estimating carrying angles using computed tomography that can enhance the reliability of the angle measurement. Data of CT scans from 25 elbow joints were processed to build segmented three-dimensional models. The cross-sectional centerlines of the ulna and the humerus were traced from the 3D models, and the angle between 2 vectors formed from the centerlines of the humerus and the ulna was defined as the "three-dimensional carrying angle." These angles were compared with those measured by simple radiograph. Two cases of angular deformity were underwent surgery based on this preoperative surgical planning, and the postoperative 3D carrying angles were evaluated using the proposed method. The mean value of the calculated three-dimensional carrying angle was 20.7 degrees +/-3.61, while it was 16.3 degrees +/-3.21 based on simple radiography without statistical difference. Based on the 3D carrying angle estimations, 2 surgical cases of cubitus deformities were planned by comparison with the normal contra-lateral elbow. Postoperative angle estimations confirmed that the corrected angles were nearly identical to the planned angles for both cases. The results of this study showed that the carrying angle can be accurately estimated using three-dimensional CT and that the proposed method is useful in evaluating deformities of the elbow with high reliability.

  19. Infant carrying: the role of increased locomotory costs in early tool development.

    Science.gov (United States)

    Wall-Scheffler, C M; Geiger, K; Steudel-Numbers, K L

    2007-06-01

    Among the costs of reproduction, carrying one's infant incurs one of the greatest drains on maternal energy, simply because of the added mass alone. Because of the dearth of archaeological evidence, however, how early bipeds dealt with the additional cost of having to carry infants who were less able to support their body weight against gravity is not particularly well understood. This article presents evidence on the caloric drain of carrying an infant in one's arms versus having a tool with which to sling the infant and carry her passively. The burden of carrying an infant in one's arms is on average 16% greater than having a tool to support the baby's mass and seems to have the potential to be a greater energetic burden even than lactation. In addition, carrying a baby in one's arms shortens and quickens the stride. An anthropometric trait that seems to offset some of the increased cost of carrying a baby in the arms is a wider bi-trochanteric width.

  20. Physical and Emotional Health Problems Experienced by Youth Engaged in Physical Fighting and Weapon Carrying

    Science.gov (United States)

    Walsh, Sophie D.; Molcho, Michal; Craig, Wendy; Harel-Fisch, Yossi; Huynh, Quynh; Kukaswadia, Atif; Aasvee, Katrin; Várnai, Dora; Ottova, Veronika; Ravens-Sieberer, Ulrike; Pickett, William

    2013-01-01

    Then aims of the current study were 1) to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11–15 years; (2) To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries) and emotional health outcomes (multiple health complaints) among adolescents within the theoretical framework of Problem Behaviour Theory. 20,125 adolescents aged 11–15 in five countries (Belgium, Israel, USA, Canada, FYR Macedonia) were surveyed via the 2006 Health Behaviour in School Aged Children survey. Prevalence was calculated for physical fighting and weapon carrying along with physical and emotional measures that potentially result from violence. Regression analyses were used to quantify associations between violence/weapon carrying and the potential health consequences within each country. Large variations in fighting and weapon carrying were observed across countries. Boys reported more frequent episodes of fighting/weapon carrying and medically attended injuries in every country, while girls reported more emotional symptoms. Although there were some notable variations in findings between different participating countries, increased weapon carrying and physical fighting were both independently and consistently associated with more frequent reports of the potential health outcomes. Adolescents engaging in fighting and weapon carrying are also at risk for physical and emotional health outcomes. Involvement in fighting and weapon carrying can be seen as part of a constellation of risk behaviours with obvious health implications. Our findings also highlight the importance of the cultural context when examining the nature of violent behaviour for adolescents. PMID:23437126

  1. Physical and emotional health problems experienced by youth engaged in physical fighting and weapon carrying.

    Directory of Open Access Journals (Sweden)

    Sophie D Walsh

    Full Text Available Then aims of the current study were 1 to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11-15 years; (2 To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries and emotional health outcomes (multiple health complaints among adolescents within the theoretical framework of Problem Behaviour Theory. 20,125 adolescents aged 11-15 in five countries (Belgium, Israel, USA, Canada, FYR Macedonia were surveyed via the 2006 Health Behaviour in School Aged Children survey. Prevalence was calculated for physical fighting and weapon carrying along with physical and emotional measures that potentially result from violence. Regression analyses were used to quantify associations between violence/weapon carrying and the potential health consequences within each country. Large variations in fighting and weapon carrying were observed across countries. Boys reported more frequent episodes of fighting/weapon carrying and medically attended injuries in every country, while girls reported more emotional symptoms. Although there were some notable variations in findings between different participating countries, increased weapon carrying and physical fighting were both independently and consistently associated with more frequent reports of the potential health outcomes. Adolescents engaging in fighting and weapon carrying are also at risk for physical and emotional health outcomes. Involvement in fighting and weapon carrying can be seen as part of a constellation of risk behaviours with obvious health implications. Our findings also highlight the importance of the cultural context when examining the nature of violent behaviour for adolescents.

  2. State Gun Law Environment and Youth Gun Carrying in the United States.

    Science.gov (United States)

    Xuan, Ziming; Hemenway, David

    2015-11-01

    Gun violence and injuries pose a substantial threat to children and youth in the United States. Existing evidence points to the need for interventions and policies for keeping guns out of the hands of children and youth. (1) To examine the association between state gun law environment and youth gun carrying in the United States, and (2) to determine whether adult gun ownership mediates this association. This was a repeated cross-sectional observational study design with 3 years of data on youth gun carrying from US states. The Youth Risk Behavior Survey comprises data of representative samples of students in grades 9 to 12 from biennial years of 2007, 2009, and 2011. We hypothesized that states with more restrictive gun laws have lower rates of youth gun carrying, and this association is mediated by adult gun ownership. State gun law environment as measured by state gun law score. Youth gun carrying was defined as having carried a gun on at least 1 day during the 30 days before the survey. In the fully adjusted model, a 10-point increase in the state gun law score, which represented a more restrictive gun law environment, was associated with a 9% decrease in the odds of youth gun carrying (adjusted odds ratio [AOR], 0.91 [95% CI, 0.86-0.96]). Adult gun ownership mediated the association between state gun law score and youth gun carrying (AOR, 0.94 [ 95% CI, 0.86-1.01], with 29% attenuation of the regression coefficient from -0.09 to -0.07 based on bootstrap resampling). More restrictive overall gun control policies are associated with a reduced likelihood of youth gun carrying. These findings are relevant to gun policy debates about the critical importance of strengthening overall gun law environment to prevent youth gun carrying.

  3. Quantifying spatially derived carrying capacity occupation: Framework for characterisation modelling and application to terrestrial acidification

    DEFF Research Database (Denmark)

    Bjørn, Anders; Margni, M.; Bulle, C.

    *year. This metric resembles that of the ecological footprint method and may be compared to the availability of land or water. The framework was applied to the terrestrial acidification impact category. The geochemical steady-state model PROFILE was used to quantify carrying capacities as deposition levels......The popularity of the ecological footprint method and the planetary boundaries concept shows an increasing interest among decision makers in comparing environmental impacts to carrying capacities of natural systems. Recently carrying capacity-based normalisation references were developed for impact...

  4. Impact of Flexibility Options on Grid Economic Carrying Capacity of Solar and Wind: Three Case Studies

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Novacheck, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-12-01

    In this study, we attempt to quantify the benefits of various options of grid flexibility by measuring their impact on two measures: economic carrying capacity and system costs. Flexibility can increase economic carrying capacity and reduce overall system costs. In some cases, options that provide a limited increase in economic carrying capacity can provide significant operational savings, thus demonstrating the need to evaluate flexibility options using multiple metrics. The value of flexibility options varies regionally due to different generation mixes and types of renewables. The more rapid decline in PV value compared to wind makes PV more dependent on adding flexibility options, including transmission and energy storage.

  5. Clinging to their Guns? The New Politics of Gun Carry in Everyday Life

    OpenAIRE

    Carlson, Jennifer

    2013-01-01

    Alongside a series of high-profile massacres over the past decade, Americans continue to turn to guns as the solution to, rather than the cause of, violent crime. Since the 1970s, most US states have significantly loosened restrictions on gun carrying for self-defense, and today, over 8 million Americans hold permits to carry guns concealed. Contrary to popular images of gun culture, this is not a white-only affair: in Michigan, whites and African Americans are licensed to carry guns at rough...

  6. On-line measurements of liquid carry-over from scrubbers using radioactive tracers

    International Nuclear Information System (INIS)

    Haugan, A.; Hassfjell, S.; Finborud, A.

    2004-01-01

    A method to measure liquid carry-over from scrubbers using gamma-emitting tracers is described and results from field tests at two onshore installations are presented. One water/1,2-ethanediol (MEG) and two hydrocarbon liquid (condensate) tracers have been used in the tests. One of the condensate tracers deposited to some extent inside the process pipe, while the other had a too high vapor pressure. The water/MEG tracer showed no MEG carry-over while the carry-over of MEG was documented to be considerable. (author)

  7. Causal assessment of occupational carrying and low back pain: results of a systematic review.

    Science.gov (United States)

    Wai, Eugene K; Roffey, Darren M; Bishop, Paul; Kwon, Brian K; Dagenais, Simon

    2010-07-01

    Occupational low back pain (LBP) is a common musculoskeletal disorder that results in high healthcare use and a heavy societal burden from morbidity and medical costs. The etiology of LBP is unclear, although numerous physical activities in the workplace have been implicated in its development. Determining the causal relationship between LBP and specific occupational activities requires a rigorous methodological approach. To conduct a systematic review of the scientific literature focused on establishing a causal relationship between occupational carrying and LBP. Systematic review of the literature was performed. Studies reporting an association between occupational carrying and LBP. Numerical association between different levels of exposure to occupational carrying and the presence or severity of LBP. A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship between occupational carrying and LBP by using the commonly used Bradford-Hill framework. The literature was searched using Medline, Embase, CINAHL, Cochrane Library, the Occupational Safety and Health (OSH-ROM) database, gray literature (eg, studies not published in peer-reviewed journals), hand-searching occupational health journals, reference lists of included studies, and content experts. Study quality was evaluated using a modified version of the Newcastle-Ottawa Scale. Levels of evidence supporting specific Bradford-Hill criteria were evaluated for different categories of carrying and types of LBP outcomes. This search yielded 2,766 citations. A total of nine high-quality studies reported on occupational carrying and LBP, including four case-control studies and five prospective cohort studies. These nine studies reported strong and consistent evidence against a statistical association between carrying and LBP. Three studies assessed dose-response, of which only one reported a dose-response trend that was not statistically

  8. Carrying Capacity Model Applied to Coastal Ecotourism of Baluran National Park, Indonesia

    Science.gov (United States)

    Armono, H. D.; Rosyid, D. M.; Nuzula, N. I.

    2017-07-01

    The resources of Baluran National Park have been used for marine and coastal ecotourism. The increasing number of visitors has led to the increasing of tourists and its related activities. This condition will cause the degradation of resources and the welfare of local communities. This research aims to determine the sustainability of coastal ecotourism management by calculating the effective number of tourists who can be accepted. The study uses the concept of tourism carrying capacity, consists the ecological environment, economic, social and physical carrying capacity. The results of the combined carrying capacity analysis in Baluran National Park ecotourism shows that the number of 3.288 people per day (151.248 tourists per year) is the maximum number of accepted tourists. The current number of tourist arrivals is only 241 people per day (87.990 tourists per year) which is far below the carrying capacity.

  9. Correlates of Weapon Carrying in School among Adolescents in Three Countries

    Czech Academy of Sciences Publication Activity Database

    Stickley, A.; Koyanagi, A.; Koposov, R.; Blatný, Marek; Hrdlička, M.; Schwab-Stone, M.; Ruchkin, V.

    2015-01-01

    Roč. 39, č. 1 (2015), s. 99-108 ISSN 1945-7359 Institutional support: RVO:68081740 Keywords : adolescent * Czech Republic * Russia * United States * weapon carrying Subject RIV: AN - Psychology Impact factor: 1.270, year: 2015

  10. Geometry of carrying simplices of 3-species competitive Lotka–Volterra systems

    International Nuclear Information System (INIS)

    Baigent, Stephen

    2013-01-01

    We investigate the existence, uniqueness and Gaussian curvature of the invariant carrying simplices of 3 species autonomous totally competitive Lotka–Volterra systems. Explicit examples are given where the carrying simplex is convex or concave, but also where the curvature is not single-signed. Our method monitors the curvature of an evolving surface that converges uniformly to the carrying simplex, and generally relies on establishing that the Gaussian image of the evolving surface is confined to an invariant cone. We also discuss the relationship between the curvature of the carrying simplex near an interior fixed point and its Split Lyapunov stability. Finally we comment on extensions to general Lotka–Volterra systems that are not competitive. (paper)

  11. Information technologies in carrying out monitoring comparisons of pedagogical higher education institutions

    Directory of Open Access Journals (Sweden)

    Вадим Валерьевич Гриншкун

    2014-12-01

    Full Text Available In article various approaches to use of information technologies when carrying out monitoring researches of higher educational institutions are described. Results of researches are considered on the example of indicators of pedagogical university.

  12. Spawner-recruit relationships and fish stock carrying capacity in aquatic ecosystems

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Myers, R.A.; Bowen, K.G.

    2003-01-01

    Few marine ecologists have addressed important questions about the relative productivity and carrying capacity of different ecosystems required to support fish populations. Whereas many researchers have investigated interannual variability in recruitment within a stock, we asked whether relations...

  13. Works carried out in the south of Cerro Largo district. Uranium prospection programme. Preliminary report

    International Nuclear Information System (INIS)

    Goso, H.

    1978-01-01

    During the carried out work of radimetric preliminary Investigation in the northeast of the uraniferous country were detected radimetric anonalias which are associated to the formation San Gregorio and Tres Islas. Later the works of prospection ratified those anomalies to which they defined in the environs other anomalies. The studies of revision of these conducted anomalies they took to conclude the necessity to carry out a detailed study of the area to that district was denominated Cerro Largo Sur

  14. Modifications carried out in Heavy Water Plant, Tuticorin for maximising productivity (Paper No. 1.6)

    International Nuclear Information System (INIS)

    Periakaruppan, M.; Sunderesan, S.; Chellapandi, D.

    1992-01-01

    Many modifications have been carried out in Heavy Water Plant, Tuticorin, after commissioning of the plant in July 1978. During the initial 4/5 years many teething problems were faced and they have been tackled effectively with suitable modifications which resulted in sustained production from the year 1984 onwards. In this paper some modifications carried out and changes in operational procedures adopted which resulted in achieving sustained production year after year since 1984 are described. (author)

  15. Reproductive and life cycle strategies in egg-carrying cyclopoid and free-spawning calanoid copepods

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Sabatini, Marian

    1994-01-01

    Egg-carrying cyclopoid copepods have lower fecundity and feeding rates, and longer egg hatching times, than free-spawning calanoid copepods. Simple demographic considerations suggest that the lower feeding and fecundity of egg-carrying cyclopoids are adaptations to the potentially elevated...... mortality of ovigerous females, while the shorter egg hatching time and higher feeding and fecundity rates found in free-spawning calanoid copepods represent adaptations to the very high mortality rates experienced by suspended eggs....

  16. Sagittal plane lumbar loading when navigating an obstacle and carrying a load.

    Science.gov (United States)

    Kiriella, Jeevaka B; Perry, Carolyn J; Hawkins, Kara M; Shanahan, Camille J; Gage, William H; Moore, Anne E

    2016-11-01

    The current study quantified lumbar loading while carrying an anterior load mass and navigating an obstacle. Eight healthy male participants walked down a walkway and crossed an obstacle under three randomised LOAD conditions; empty-box (2 KG), five kilogram (5 KG) and ten kilogram (10 KG). Each walk was assessed at two events: left foot mid-stance (LMS) and right toe-crossing (TC) to characterise any changes from approach to crossing. Measures of interest included: trunk pitch, L4/L5 joint moment, compression, joint anterior-posterior shear and erector spinae activation. Findings demonstrate that obstacle crossing extended posture by 50, 41, 44%, respectively for each carried load magnitude. Further, these results indicate that shear rather than compressive loading may be an important consideration during crossing due to increase by 8, 9, 22% from LMS to TC for each load magnitude tested. These results provide insight into sagittal lumbar loading when navigating an obstacle while carrying a load. Practitioner Summary: The risk of carrying while navigating obstacles on the lumbar spine is not completely understood. The forces at the lumbar spine while simultaneously carrying and obstacle crossing were analysed. Data indicate that carrying and obstacle crossing influence lumbar shear loads, thereby moderately increasing the relative risk at lumbar spine.

  17. Evaluating Beijing's human carrying capacity from the perspective of water resource constraints.

    Science.gov (United States)

    Zhang, Yingxuan; Chen, Min; Zhou, Wenhua; Zhuang, Changwei; Ouyang, Zhiyun

    2010-01-01

    As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city's future development. We developed a method to quantify the carrying capacity of Beijing's water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45:22:33 (% of total, respectively), an optimized structure as 40:20:40, and an ideal structure as 50:15:35. We also considered four domestic water quotas: 55, 75, 95, and 115 m3/(person x yr). The urban carrying capacity of 10-12 million was closest to Beijing's actual 2003 population for all three water-use structures with urban domestic water use of 75 m3/(person x yr). However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5-6 million. Thus, Beijing's population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing's excessive population and propose measures to mitigate these problems.

  18. Carrying capacity of U.S. agricultural land: Ten diet scenarios

    Directory of Open Access Journals (Sweden)

    Christian J. Peters

    2016-07-01

    Full Text Available Abstract Strategies for environmental sustainability and global food security must account for dietary change. Using a biophysical simulation model we calculated human carrying capacity under ten diet scenarios. The scenarios included two reference diets based on actual consumption and eight “Healthy Diet” scenarios that complied with nutritional recommendations but varied in the level of meat content. We considered the U.S. agricultural land base and accounted for losses, processing conversions, livestock feed needs, suitability of land for crops or grazing, and land productivity. Annual per capita land requirements ranged from 0.13 to 1.08 ha person-1 year-1 across the ten diet scenarios. Carrying capacity varied from 402 to 807 million persons; 1.3 to 2.6 times the 2010 U.S. population. Carrying capacity was generally higher for scenarios with less meat and highest for the lacto-vegetarian diet. However, the carrying capacity of the vegan diet was lower than two of the healthy omnivore diet scenarios. Sensitivity analysis showed that carrying capacity estimates were highly influenced by starting assumptions about the proportion of cropland available for cultivated cropping. Population level dietary change can contribute substantially to meeting future food needs, though ongoing agricultural research and sustainable management practices are still needed to assure sufficient production levels.

  19. Profile of women who carried out smoking cessation treatment: a systematic review.

    Science.gov (United States)

    Pereira, Caroline Figueira; de Vargas, Divane

    2015-01-01

    OBJECTIVE Analyze the profile of women, in health services, who carry out treatment for smoking cessation. METHODS Systematic review that used the following sources of information: Cummulative Index to Nursing and Allied Health Literature (CINAHL), PubMed, Biblioteca Virtual em Saúde (BVS), Scopus and Web of Science. We included quantitative studies that addressed the characterization of women, in health services, who carried out treatment for smoking cessation, resulting in 12 articles for analysis. The assessment of the methodological quality of the studies was performed using the instrument MAStARI from Joanna Briggs Institute. RESULTS The predominant profile of women who carried out treatment for smoking cessation in health services was composed of white, married, employed, and highly level educated women. Women who carried out the treatment for smoking cessation in specialized services had a more advanced age, were white, were married and had a diagnosis of depression. The quality level of most studies was moderate. CONCLUSIONS The profile of women who carry out treatment for smoking cessation, either in general or specialized health services, is composed of white, married, and highly level educated women. Publications about smoking women are scarce and the lack of Brazilian studies characterizing the profile of women who start treatment for smoking cessation shows the need for studies that explore this subject.

  20. Population pressure and human carrying capacity in selected locations of Machakos and Kitui districts.

    Science.gov (United States)

    Bernard, F E; Thom, D J

    1981-04-01

    The nature and magnitude of population pressure in Machakos and Kitui Districts of Kenya were investigated. Specific study objectives were: 1) to examine the roots and evolution of the problem; 2) to compute carrying capacity for a sample of locations and ecozones in the 2 districts; and 3) to consider agricultural and demographic implications of the findings. Carrying capacity is defined as the number of people and the level of their activities which a region is able to sustain in perpetuity at an acceptable quality of life and without land deterioration. A methodology for calculating human carrying capacity utilizing crude soil, ecological, crop yield, and land use data for 41 locations in Machakos and Kitui Districts is demonstrated. Analysis and a comparison of population carrying capacities within the study area reveals that Machakos has reached a critical level of population pressure. To the north in Mbere and eastward in Kitui there are areas that are not currently experiencing population pressure, but it is likely that as the pressure in western Machakos becomes more acute, movement into these adjacent lands of relatively sparse settlement will increase. Signs of environmental stress resulting from overpopulation are evident throughout Machakos. The methodology used for estimating population pressure provided reasonably accurate carrying capacity estimates, but the methodology could be refined. Vigorous efforts to rejuvenate the land through soil and water conservation have been undertaken, but these have been insufficient and must be increased. Such efforts will fail unless the basic problem of population pressure in the marginal lands is resolved.

  1. Profile of women who carried out smoking cessation treatment: a systematic review

    Directory of Open Access Journals (Sweden)

    Caroline Figueira Pereira

    2015-01-01

    Full Text Available OBJECTIVE Analyze the profile of women, in health services, who carry out treatment for smoking cessation. METHODS Systematic review that used the following sources of information: Cummulative Index to Nursing and Allied Health Literature (CINAHL, PubMed, Biblioteca Virtual em Saúde (BVS, Scopus and Web of Science. We included quantitative studies that addressed the characterization of women, in health services, who carried out treatment for smoking cessation, resulting in 12 articles for analysis. The assessment of the methodological quality of the studies was performed using the instrument MAStARI from Joanna Briggs Institute. RESULTS The predominant profile of women who carried out treatment for smoking cessation in health services was composed of white, married, employed, and highly level educated women. Women who carried out the treatment for smoking cessation in specialized services had a more advanced age, were white, were married and had a diagnosis of depression. The quality level of most studies was moderate. CONCLUSIONS The profile of women who carry out treatment for smoking cessation, either in general or specialized health services, is composed of white, married, and highly level educated women. Publications about smoking women are scarce and the lack of Brazilian studies characterizing the profile of women who start treatment for smoking cessation shows the need for studies that explore this subject.

  2. Modification Of Carry-Blair Transport Media For Storage Salmonella typhi

    Directory of Open Access Journals (Sweden)

    Yati Supriatin

    2016-09-01

    Full Text Available The aim of this study was to determine transport media modification as alternative media to replace Carry Blair. One type of transport media that often use to carry faeces specimens suspected to contain Salmonella typhi is Carry-Blair media. Studies have been conducted experimentally by storing Salmonella typhi on alternative transport media with Peptone composition, disodium Phosphate, Sodium chloride, Calcium chloride, which is made using a semi-solid and Carry-Blair as a control. Three variety of storage was done (0 hour,6 hours,9 hours at a temperature 4⁰-8⁰C and then Salmonella typhi was inoculated in Salmonella Shigella Agar using spread plate technique incubated during 24 hours at 37⁰C, counted the number of colonies by the plate count method using the colony counter. The results of ANOVA could be concluded that modification media could be use as alternative media replace Carry-Blair at 6 hours. Based on regression correlation test was assumed that the Salmonella typhi bacteria still life at less than 11 hours 54 minutes.

  3. Occurrence of Enterobacter hormaechei carrying blaNDM-1 and blaKPC-2 in China.

    Science.gov (United States)

    Yang, Biwei; Feng, Yu; McNally, Alan; Zong, Zhiyong

    2018-02-01

    Three carbapenem-resistant clinical isolates of the Enterobacter cloacae complex (ECC) were recovered from different patients in a hospital. All 3 isolates carried 2 carbapenemase genes bla KPC-2 and bla NDM-1 . A study was performed to characterize their relatedness and to investigate possible links among the patients. Whole genome sequencing revealed that the isolates were Enterobacter hormaechei and belonged to ST177 of the ECC. There were 19-142 single nucleotide polymorphisms (SNPs) between the isolates, suggesting that the isolates were likely from a central reservoir, which might have existed for some time. bla KPC-2 and bla NDM-1 were carried on 2 different IncF-type plasmids in the isolates. The 3 bla NDM-1 -carrying plasmids were almost identical and were self-transmissible, while the bla KPC-2 -carrying plasmids were only transmissible in the presence of the bla NDM-1 -carrying plasmid. The source of and direct links among them were not identified, suggesting a hospital transmission of a common multidrug resistant strain. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The evolution of carrying capacity in constrained and expanding tumour cell populations.

    Science.gov (United States)

    Gerlee, Philip; Anderson, Alexander R A

    2015-08-12

    Cancer cells are known to modify their micro-environment such that it can sustain a larger population, or, in ecological terms, they construct a niche which increases the carrying capacity of the population. It has however been argued that niche construction, which benefits all cells in the tumour, would be selected against since cheaters could reap the benefits without paying the cost. We have investigated the impact of niche specificity on tumour evolution using an individual based model of breast tumour growth, in which the carrying capacity of each cell consists of two components: an intrinsic, subclone-specific part and a contribution from all neighbouring cells. Analysis of the model shows that the ability of a mutant to invade a resident population depends strongly on the specificity. When specificity is low selection is mostly on growth rate, while high specificity shifts selection towards increased carrying capacity. Further, we show that the long-term evolution of the system can be predicted using adaptive dynamics. By comparing the results from a spatially structured versus well-mixed population we show that spatial structure restores selection for carrying capacity even at zero specificity, which poses a solution to the niche construction dilemma. Lastly, we show that an expanding population exhibits spatially variable selection pressure, where cells at the leading edge exhibit higher growth rate and lower carrying capacity than those at the centre of the tumour.

  5. Categorical and continuous - disentangling the neural correlates of the carry effect in multi-digit addition

    Directory of Open Access Journals (Sweden)

    Dressel Katharina

    2010-11-01

    Full Text Available Abstract Background Recently it was suggested that the carry effect observed in addition involves both categorical and continuous processing characteristics. Methods In the present study, we aimed at identifying the specific neural correlates associated with processing either categorical or continuous aspects of the carry effect in an fMRI study on multi-digit addition. Results In line with our expectations, we observed two distinct parts of the fronto-parietal network subserving numerical cognition to be associated with either one of these two characteristics. On the one hand, the categorical aspect of the carry effect was associated with left-hemispheric language areas and the basal ganglia probably reflecting increased demands on procedural and problem solving processes. Complementarily, the continuous aspect of the carry effect was associated with increased intraparietal activation indicating increasing demands on magnitude processing as well as place-value integration with increasing unit sum. Conclusions In summary, the findings suggest representations and processes underlying the carry effect in multi-digit addition to be more complex and interactive than assumed previously.

  6. The effect of the spaceship carrying on the biological characters and sod activity of eggplant

    International Nuclear Information System (INIS)

    Wang Shiheng; Zhang Ya; Zhu Shuijin; Wang Yanfan

    2004-01-01

    The effects of the space shuttle carrying on the growth and biological characters of eggplant SP 1 population were studied. The results showed that the effect of space shuttle carrying on the growth and development of eggplant SP 1 were very significant on the characters such as the plant height, reproductive development, leaf size, fruit length, fruit quality and fruiting rate etc, especially on the plant development and the fruit size, and it is hopeful to select some good eggplant germplasm or cultivars from the population. The SOD activity showed that the SOD level in the mutant-1 plant was one time more than that in control plant, indicating that the space shuttle carrying may increase the expression of some genes and lead to the great change in morphological characters

  7. First Identification of a Patient Colonized With Klebsiella pneumoniae Carrying blaNDM-1 in Taiwan

    Directory of Open Access Journals (Sweden)

    Hua-Shin Wu

    2010-11-01

    Full Text Available New Delhi metallo-β-lactamase 1 (NDM-1 is a novel type of metallo-β-lactamase (MBL. Enterobacteriaceae carrying this NDM-1 encoding gene, blaNDM-1, have been identified worldwide. Bacteria carrying blaNDM-1 are not only resistant to carbapenem, but also highly resistant to many classes of antibiotics, which indicate the importance of prompt identification of these bacteria and implementation of strict infection control measures to prevent their transmission. Here, we report the first identification and management of a patient colonized with Klebsiella pneumoniae carrying blaNDM-1 in Taiwan, who returned from New Delhi where he had been hospitalized for a gun-shot injury.

  8. Estimating the carrying capacity of green mussel cultivation by using net nutrient removal model.

    Science.gov (United States)

    Srisunont, Chayarat; Babel, Sandhya

    2016-11-15

    This study aims to evaluate the nutrient removal potential and carrying capacity of green mussel cultivation by using the mass balance model. The developed model takes into consideration the green mussel growth rate, density and chlorophyll a concentration. The data employed in this study were based on culture conditions at Sriracha Fisheries Research Station, Thailand. Results show that net nutrient removal by green mussel is 3302, 380, and 124mg/year/indv for carbon, nitrogen, and phosphorus respectively. The carrying capacity of green mussel cultivation was found to be 300indv/m 2 based on chlorophyll a concentration which will not release phosphorus in the water environment beyond the standard (45μg-PO 4 -3 -P/L). Higher chlorophyll a concentration results in lowered green mussel carrying capacity. This model can assist farm operators with possible management strategies for a sustainable mussel cultivation and protection of the marine environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Carrying an anti-nuclear-power badge in the teaching profession

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The carrying of an anti-nuclear-power badge by a teacher during school hours violates the order to practice reticence in political activities. At the beginning of 1977 some teachers, the plaintiff as well, carried anti-nuclear-power badges, i.e. a round badge with a stylized red sun on a yellow background with the inscription 'Nuclear power - No, thank you'. Following a general direction by the educational authorities, the headmistress forbade plaintiff on 4.11.77 to visibly carry this badge during lessons. This protest having been without success, action was brought with partial success at the Administrative and Higher Administrative Court. The Federal Administrative Court dismissed the case. (orig./HSCH) [de

  10. Correlates of weapon carrying among high school students in the United States

    Directory of Open Access Journals (Sweden)

    Rudatsikira Emmanuel

    2008-07-01

    Full Text Available Abstract Background Deaths and injuries arising from interpersonal violence among adolescents are major public health concerns in the United States. The bearing of weapons among adolescents is a critical factor in many of these deaths and injuries. Methods A secondary analysis of the 2005 United States Youth Risk Behavior Surveillance System Survey data was carried out to examine the variables associated with self-reported history of weapon carrying on school property among high school students. We used logistic regression analysis to assess the associations. Results Of the 13,707 respondents who participated in the survey, 10.2% of males and 2.6% of females reported carrying a weapon on school property. In multivariate logistic regression analysis, males were more likely to report having carried a weapon than females (odds ratio (OR = 5.58; 95% confidence interval (CI [4.23, 7.62]. Self-reported race/ethnicity was also associated with weapon carrying. Other variables positively associated with weapon carrying at school were substance use (OR = 1.77; 95% CI [1.16, 2.68], depression (OR = 1.44; 95% CI [1.10, 1.89], suicidal ideation (OR = 1.64; 95% CI [1.23, 2.19], having had property stolen or deliberately damaged at school (OR = 1.55; 95% CI [1.21, 1.98], having been raped (OR = 1.70; 95% CI [1.22, 2.37], having been threatened or injured with a weapon on school property (OR = 2.19; 95% CI [1.63, 2.95], and having engaged in physical fighting (OR = 2.02; 95% CI [1.56, 2.63]. Conclusion This research identifies factors that are associated with weapon bearing among adolescents in the United States. These factors may be important in the design of interventions aimed at improving school safety and adolescent health.

  11. Missile Captive Carry Monitoring and Helicopter Identification Using a Capacitive Microelectromechanical Systems Accelerometer

    Energy Technology Data Exchange (ETDEWEB)

    Hatchell, Brian K.; Mauss, Fredrick J.; Amaya, Ivan A.; Skorpik, James R.; Silvers, Kurt L.; Marotta, Steve

    2012-03-27

    Military missiles are exposed to many sources of mechanical vibration that can affect system reliability, safety, and mission effectiveness. The U. S. Army Aviation and Missile Research Development and Engineering Center (AMRDEC) has been developing missile health monitoring systems to assess and improve reliability, reduce life cycle costs, and increase system readiness. One of the most significant exposures to vibration occurs when the missile is being carried by a helicopter or other aviation platform, which is a condition known as captive carry. Recording the duration of captive carry exposure during the missile’s service life can enable the implementation of predictive maintenance and resource management programs. Since the vibration imparted by each class of helicopter varies in frequency and amplitude, tracking the vibration exposure from each helicopter separately can help quantify the severity and harmonic content of the exposure. Under the direction of AMRDEC staff, engineers at the Pacific Northwest National Laboratory have developed a Captive Carry Health Monitor (CCHM) for the Hellfire II missile. The CCHM is an embedded usage monitoring device installed on the outer skin of the Hellfire II missile to record the cumulative hours the host missile has been in captive carry mode. To classify the vibration by class of helicopter, the CCHM analyzes the amplitude and frequency content of the vibration with the Goertzel algorithm to detect the presence of distinctive rotor harmonics. Cumulative usage data are accessible in theater from an external display; monthly usage histograms are accessible through an internal download connector. This paper provides an overview of the CCHM electrical and package design, describes field testing and data analysis techniques used to monitor captive carry identify and the class of helicopter, and discusses the potential application of missile health and usage data for real-time reliability analysis and fleet management.

  12. Botanical Composition, Grass Production, and Carrying Capacity of Pasture in Timor Tengah Selatan District

    Directory of Open Access Journals (Sweden)

    V. E. Se’u

    2015-12-01

    Full Text Available This study was conducted to analyze the botanical composition, grass production, carrying capacity, and potential production of nutrients in pasture located in Timor Tengah Selatan Regency. The experiment was conducted from February to July 2013, using field survey method. The botanical composition, grass production and carrying capacity on real condition were analyzed descriptively, while the grass production and carrying capacity based of cutting arrangement were analyzed by using randomized block factorial design with 3 altitude locations (Sub District of Mollo Utara with altitude of 1007 m above sea level; Sub District of Noebeba, 500 m ASL, and Sub District of Amanuban Selatan, 65 m ASL x 2 cutting intervals (1 and 2 month and 5 replications. The results showed that the grass type dominated the pasture in the Sub District of Mollo Utara, while legum type was more dominant in the pasture in the Sub Districts of Noebeba and Amanuban Selatan. The potential production of dry matter grass in Timor Tengah Selatan Regency based on real condition was 150 to 390 kg/ha/yr, this could accommodate 0.24 to 0.63 AU/ha/yr. The arrangement of cutting interval by 1 month in Mollo Utara and 2 months in Noebeba and Amanuban Selatan could increase (P<0.05 grass production and carrying capacity. The potential productions of grass nutrients were higher in Sub District of Mollo Utara, while potential production of grass dry matter was higher in Sub Districts of Noebeba and Amanuban Selatan. It was concluded that grass dry matter potential production and carrying capacity in Timor Tengah Selatan Regency were low. The arrangement of cutting interval could increase grass dry matter potential production, carrying capacity, nutrition production, and quality of nutrition.

  13. Performance of women with fibromyalgia in walking up stairs while carrying a load

    Directory of Open Access Journals (Sweden)

    Daniel Collado-Mateo

    2016-02-01

    Full Text Available Background. Fibromyalgia is a chronic disease characterized by widespread pain and other associated symptoms. It has a relevant impact on physical fitness and the ability to perform daily living tasks. The objective of the study was to analyze the step-by-step-performance and the trunk tilt of women with fibromyalgia in the 10-step stair climbing test compared with healthy controls. Methods. A cross-sectional study was carried out. Twelve women suffering from fibromyalgia and eight healthy controls were recruited from a local association. Participants were asked to climb 10 stairs without carrying a load and 10 stairs carrying a load of 5 kg in each hand. Mediolateral trunk tilt was assessed using the “Functional Assessment of Biomechanics (FAB” wireless motion capture device, and the time between steps was assessed via weight-bearing insoles. Results. Trunk tilt in the stair-climbing task carrying a load was significantly higher in women with fibromyalgia when compared to the healthy controls (2.31 (0.63 vs. 1.69 (0.51 respectively. The effect of carrying a load was significantly higher for women with fibromyalgia compared with healthy controls at the intermediate and final part of the task. Discussion. Trunk tilt during stair climbing while carrying a load was higher in women with FM, which could increase the risk of falling. Additionally, women with FM experienced a higher pace slowdown as a consequence of the load, which supports the need of including specific strength and resistance training to physical therapies for this population.

  14. Streptococcus salivarius strains carry either fibrils or fimbriae on the cell surface.

    Science.gov (United States)

    Handley, P S; Carter, P L; Fielding, J

    1984-01-01

    Strains of Streptococcus salivarius were screened by negative staining for the presence of surface structures. Two structural subgroups were found, carrying either fibrils or fimbriae, projecting from the cell surface. Eight strains carried a very dense peritrichous array of fibrils of two distinct lengths. Long fibrils had an average length of 175 nm, and short fibrils had an average length of 95 nm. Two strains carried only long fibrils, one strain carried only short fibrils, and another strain carried a lateral tuft of very prominent fibrils of two lengths, with a fibrillar fuzz covering the remainder of the cell surface. In all the strains in which they were present, the long fibrils were unaffected by protease or trypsin treatment. In contrast, the short fibrils were completely digested by protease and partially removed by trypsin. Neither long nor short fibrils were affected structurally by mild pepsin digestion or by lipase. The Lancefield extraction procedure removed both long and short fibrils. These twelve fibrillar strains were therefore divisible into four structural subgroups. Extracts of all the fibrillar strains reacted with group K antiserum. The second main structural subgroup consisted of nine strains of S. salivarius, all of which carried morphologically identical, flexible fimbriae arranged peritrichously over the cell surface. The fimbriae were structurally distinct from fibrils and measured 0.5 to 1.0 micron long and 3 to 4 nm wide, with an irregular outline and no obvious substructure. There was no obvious reduction in the number of fimbriae after protease or trypsin treatment. Extracts of the fimbriated strains did not react with the group K antiserum. The two serological and structural subgroups could also be distinguished by colony morphology. Images PMID:6197404

  15. Conditions for the management of carrying capacity in the parks of Parks&Benefits

    DEFF Research Database (Denmark)

    Brandt, Jesper; Holmes, Esbern

    2011-01-01

    Growth in the number of visitors is an upcoming problem in nature parks. Nature parks are at the same time facing increasing demand, falling public appropriations and receding focus on their conservation functions. To ensure a balancing of nature protection and economic utilization the concept...... of carrying capacity has received increasing attention among park-authorities all over the world. Carrying capacities understood as limits or standards not to be exceeded to protect a supporting landscape system are not scientifically determined sizes. They are a result of political decision processes among...

  16. Seasonal dynamics in wheel load-carrying capacity of a loam soil in the Swiss Plateau

    DEFF Research Database (Denmark)

    Gut, S.; Chervet, A.; Stettler, Matthias

    2015-01-01

    Subsoil compaction is a major problem in modern agriculture caused by the intensification of agricultural production and the increase in weight of agricultural machinery. Compaction in the subsoil is highly persistent and leads to deterioration of soil functions. Wheel load-carrying capacity (WLCC...... and cropping systems (mouldboard ploughing, direct drilling, permanent grassland), and the computed WLCC was compared with real wheel loads to obtain the number of trafficable days (NTD) for various agricultural machines. Wheel load-carrying capacity was higher for the top than the standard tyres...

  17. Introducing carrying capacity-based normalisation in LCA: framework and development of references at midpoint level

    DEFF Research Database (Denmark)

    Bjørn, Anders; Hauschild, Michael Zwicky

    2015-01-01

    There is currently a weak or no link between the indicator scores quantified in life cycle assessment (LCA) and the carrying capacity of the affected ecosystems. Such a link must be established if LCA is to support assessments of environmental sustainability and it may be done by developing...... capacity of a reference region divided by its population and thus describes the annual personal share of the carrying capacity.The developed references can be applied to indicator results obtained using commonly applied characterisation models in LCIA. The European NR are generally lower than the global NR...

  18. Cuttings-carried theory and erosion rule in gas drilling horizontal well

    Directory of Open Access Journals (Sweden)

    Wei Na

    2014-01-01

    Full Text Available In gas horizontal drilling, the gas with cuttings will go through the annulus at high speed which will lead strong erosion to the drill tools. This paper proposes a cuttings-carried theory and modified the critical cuttings-carried model for the gas-solid flow. Meanwhile, the erosive energy is obtained through simulating the gas-solid mixture in different conditions. The study result has positive significance on the determination of reasonable injection volume by optimizing construction parameters of horizontal well in gas drilling.

  19. Biorheological properties of reconstructed erythrocytes and its function of carrying-releasing oxygen.

    Science.gov (United States)

    Wang, Xiang; Gao, Wei; Peng, Weiyan; Xie, Jiaxin; Li, Yaojin

    2009-01-01

    Erythrocyte shape and biomechanical properties have close relation to its physiological function. In this research the erythrocyte was reconstructed with natural structure protein and lipids based on cellular mechanics and hemorheology concepts. The biomechanical properties of the reconstructed erythrocyte were determined with the micropipette aspiration system. The shapes of reconstructed erythrocyte were obtained with electron scanning microscope. The oxygen carrying-releasing function was analyzed with the HEMOX analyzer from TCS, the experimental results indicated that the reconstructed erythrocytes were similar to the natural erythrocyte: having biconcave disc shape, good deformability and carrying-releasing oxygen function.

  20. Risk-premia, Carry-trade Dynamics, and Economic Value of Currency Speculation

    DEFF Research Database (Denmark)

    Wagner, Christian

    2012-01-01

    In this paper, we derive the dynamics and assess the economic value of currency speculation by formalizing the concept of a trader inaction range. We show that exchange rate returns comprise a time-varying risk-premium and that uncovered interest parity (UIP) holds in a speculative sense. The often......-cited ‘forward bias puzzle’ originates from the omission of the risk-premium in standard UIP tests. Consistent with its popularity among market professionals, the carry-trade strategy can be rationalized as it systematically collects risk-premia, however, the economic value generated by bilateral carry...

  1. On the first tachinid fly (Diptera, Tachinidae carrying Asclepiadoideae pollinaria in the Neotropical Region

    Directory of Open Access Journals (Sweden)

    Silvio Shigueo Nihei

    2011-09-01

    Full Text Available On the first tachinid fly (Diptera, Tachinidae carrying Asclepiadoideae pollinaria in the Neotropical Region. This paper reports the first Neotropical Tachinidae species possibly associated to pollination of Asclepiadoideae: a female of Euacaulona sumichrasti Townsend, 1908 (Diptera, Tachinidae, Phasiinae, Trichopodini carrying pollinaria of Gonolobus parviflorus Decne., 1844 (Apocynaceae, Asclepiadoideae, Asclepiadeae: Gonolobinae attached to its proboscis. The fly specimen was collected in Paraguay, Departamento Canindeyú. The pollinarium is illustrated and described herein. This represents the first anthophilous record to G. parviflorus and to the genus.

  2. EVALUATION OF SHEAR STRENGTH FOR UPPER SLABS OF CAISSON FOUNDATION BASED ON LOAD CARRYING MECHANISM

    Science.gov (United States)

    Hattori, Hisamichi; Tadokoro, Toshiya; Tanimura, Yukihiro; Nishioka, Hidetoshi; Watanabe, Tadatomo; Maruyama, Osamu

    In upper slabs of caisson foundation, a seismic desi gn is difficult with an incr ease in earthquake load. So we carried out loading tests and FEM analysis for upper slabs of caisson foundation. As a result, we proposed a new design method which takes into co nsideration the effective width on the pull out side based on crack pattern of test specimens, which is not considered in the existing design method. Moreover, we proposed a rational design method based on load carrying mechanism for upper slabs of caisson foundation.

  3. Carry-chain propagation delay impacts on resolution of FPGA-based TDC

    International Nuclear Information System (INIS)

    Dong Lei; Yang Junfeng; Song Kezhu

    2014-01-01

    The architecture of carry chains in Field-Programmable Gate Array (FPGA) is introduced in this paper. The propagation delay time of the rising and falling edges in the carry chains are calculated according to the architecture and they are predicted not equal in most cases. Tests show that the measuring results of the propagation delay time in EP3C120F484C8N series FPGA of Altera are in line with the inference. The difference of propagation delay time results in different accuracies of Time-to-Digital Converter (TDC). This phenomenon shall be considered in the design of TDC implemented in FPGA. It can ensure better accuracy. (authors)

  4. Process for carrying out a chemical reaction with ionic liquid and carbon dioxide under pressure

    NARCIS (Netherlands)

    Kroon, M.C.; Shariati, A.; Florusse, L.J.; Peters, C.J.; Van Spronsen, J.; Witkamp, G.J.; Sheldon, R.A.; Gutkowski, K.I.

    2006-01-01

    The invention is directed to a process for carrying out a chemical reaction in an ionic liquid as solvent and CO2 as cosolvent, in which process reactants are reacted in a homogeneous phase at selected pressure and temperature to generate a reaction product at least containing an end-product of the

  5. Who Carries the Burden of Reproductive Health and AIDS Programs? - Evidence from OECD Donor Countries

    NARCIS (Netherlands)

    H.P. van Dalen (Hendrik)

    2006-01-01

    textabstractThis paper tries to establish who carries the burden in supporting reproductive health and AIDS programs worldwide. The 1994 International Conference of Population and Development (ICPD) in Cairo established goals for the expansion of assistance in matters of reproductive health and

  6. An evaluation of the carrying angle of the elbow joint in adolescents

    African Journals Online (AJOL)

    McRoy

    Department of Anatomy and Orthopedics, Sri Lakshmi Narayana Institute of Medical Sciences,. Pondicherry - 605 502 ... forearm deviates laterally from the long axis of the humerus, with the arm extended and the palm ... for elbow reconstruction. Key words: Carrying angle, elbow joint, adolescent, forearm, humerus, ulna ...

  7. Reduced fertility after the crash of a U.S. bomber carrying nuclear weapons?

    DEFF Research Database (Denmark)

    Juel, K

    1995-01-01

    A register-based study was performed to elucidate whether workers employed on the Thule air base in the clean-up period after the crash of a U.S. B-52 bomber carrying nuclear bombs had reduced fertility, as measured by the numbers of liveborn children. The highest birth rates were among 25-34-year...

  8. An evaluation of the carrying angle of the elbow joint in adolescents ...

    African Journals Online (AJOL)

    Aim: This study was conducted to evaluate the elbow carrying angle in normal adolescents of South India and also analyze the data statistically to find out any significant difference in the angle between the different groups of subjects within the study population. Methods: 60 adolescents with ages varying from 17 to 20 years ...

  9. E-Books in Academic Libraries: Results of a Survey Carried out in Sweden and Lithuania

    Science.gov (United States)

    Maceviciute, Elena; Wilson, T. D.; Gudinavicius, Arunas; Šuminas, Andrius

    2017-01-01

    Introduction: This paper reports on a study of e-books issues in academic libraries in two European countries representative of small language markets--Sweden and Lithuania. Method: Questionnaire surveys, using the same instrument, were carried out in Swedish and Lithuanian academic libraries. Analysis: Quantitative analysis was performed using…

  10. 49 CFR 176.192 - Cargo handling equipment for freight containers carrying Class 1 (explosive) materials.

    Science.gov (United States)

    2010-10-01

    ...) Materials Handling Class 1 (explosive) Materials in Port § 176.192 Cargo handling equipment for freight containers carrying Class 1 (explosive) materials. (a) Except in an emergency, only cargo handling equipment... load, unload, or handle freight containers containing Division 1.1 or 1.2 (explosive) materials. (b...

  11. Analyzing changes in productivity and carrying capacity under planned grazing in Madiama Commune, Mali (West Africa)

    OpenAIRE

    Badini, Oumar; Stockle, C.; Jones, J.; Bostick, M.; Kodio, Amadou; Keita, Moussa

    2004-01-01

    This presentation addresses the problems of overgrazing and degradation of pasture land. Policies that can increase pasture productivity and improve the carrying capacity and soil quality of pastures are assessed using CropSyst simulation modeling. Optimal grazing intensity and intervals (rotational grazing) are evaluated and discussed, based on model analysis from the Madiama commune in Mali (West Africa). ME (Management Entity)

  12. Carrying capacity of edge-cracked columns under concentric vertical loads

    NARCIS (Netherlands)

    Yazdchi, K.; Anaraki, A.R. Gowhari

    2008-01-01

    This paper analyses the carrying capacity of edge-cracked columns with different boundary conditions and cross sections subjected to concentric vertical loads. The transfer matrix method, combined with fundamental solutions of the intact columns (e.g. columns with no cracks) is used to obtain the

  13. Construction of a novel lentiviral vector carrying human B-domain ...

    African Journals Online (AJOL)

    ... integration were detected in all cell lines after transfection. A novel lentiviral vector carrying human FVIII³BD was constructed, which was able to transfect different mammalian cell types accompanied by high-level activity. This lentiviral vector may provide a theoretical basis for the gene therapy of patients with hemophilia ...

  14. Meta-analysis of carrying capacity and abundance-area relationships in marine fish species

    DEFF Research Database (Denmark)

    Mantzouni, Irene

    Knowledge on the carrying capacity and the abundance-area relationships of fish is critical to evaluate the impacts of exploitation and climate on the sustainability and also the recovery potential of the populations. Of particular interest is climate change, inducing major consequences for popul...

  15. Towards a strengthening of inspections carried out on pressurised equipment and pipework..

    International Nuclear Information System (INIS)

    Noel, St.

    2010-01-01

    Following the fast presidential election, a major restructuring of the administrative landscape was set in motion. Tasks that historically were the responsibility of the Ministry of Industry are now carried out by the Ministry of Sustainable Development, which in particular is responsible for the whole policy to do with the prevention of technological risks. The General Directorate for the Prevention of Risks (Direction generale de la prevention des risques (DGPR)) of this ministry is now responsible for controlling technological risks, opening up new perspectives in terms of managing accidental risks and offering a new opportunity for an 'integrated' approach, making it possible to deal with an industrial installation in all its facets. Within the DGPR, the Office for the Safety of Industrial Equipment (bureau de la securite des equipements industriels (BSEI)) is responsible for the safety of pressurised equipment, as well as pipes carrying gas, inflammable liquids and chemical products. After a quick presentation of the inspections carried out on this equipment, issues to do with their safety will be dealt with and in particular: - the suitability of inspections carried out in the tight of faults that are likely to occur and develop in the structures; - control of ageing; - management of the quality of new equipment. (author)

  16. Think locally, act globally: How research carried out in Brazil helped ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2018-04-13

    Apr 13, 2018 ... Think locally, act globally: How research carried out in Brazil helped shape global policies. Dr Cesar Victora, recipient of the 2017 John Dirks Canada Gairdner Global Health ... IDRC and DHSC partner to fight antimicrobial resistance in animals. IDRC and the United Kingdom's Global AMR Innovation ...

  17. Summary of R and D work carried out in Sri Lanka for the development of RVNRL

    International Nuclear Information System (INIS)

    Karunaratne, S.W.

    1994-01-01

    This paper discusses the advantages of radiation vulcanization of natural rubber latex and research and development carried out in this particular field. It emphasises types of centrifuge latex used, stability of this centrifuged latex, use of sensitizer, effect of leaching, antioxidants, use of low energy electron beam and training and human resources development in this field

  18. Mitigating the impact of sanitizer carry-over on pathogen monitoring

    Science.gov (United States)

    A number of sanitizer solutions are utilized in poultry processing to aid in reducing or destroying pathogenic bacteria. Post-treatment pathogen monitoring may lead to false-negative results due to carry-over of sanitizer to the analyzed rinse solution. This study was conducted to determine the suit...

  19. Forewarning Model of Regional Water Resources Carrying Capacity Based on Combination Weights and Entropy Principles

    Directory of Open Access Journals (Sweden)

    Rongxing Zhou

    2017-10-01

    Full Text Available As a new development form for evaluating the regional water resources carrying capacity, forewarning regional water resources of their carrying capacities is an important adjustment and control measure for regional water security management. Up to now, most research on this issue have been qualitative analyses, with a lack of quantitative research. For this reason, an index system for forewarning regional water resources of their carrying capacities and grade standards, has been established in Anhui Province, China, in this paper. Subjective weights of forewarning indices can be calculated using a fuzzy analytic hierarchy process, based on an accelerating genetic algorithm, while objective weights of forewarning indices can be calculated by using a projection pursuit method, based on an accelerating genetic algorithm. These two kinds of weights can be combined into combination weights of forewarning indices, by using the minimum relative information entropy principle. Furthermore, a forewarning model of regional water resources carrying capacity, based on entropy combination weight, is put forward. The model can fully integrate subjective and objective information in the process of forewarning. The results show that the calculation results of the model are reasonable and the method has high adaptability. Therefore, this model is worth studying and popularizing.

  20. Charged Particle Dynamics in the Magnetic Field of a Long Straight Current-Carrying Wire

    Science.gov (United States)

    Prentice, A.; Fatuzzo, M.; Toepker, T.

    2015-01-01

    By describing the motion of a charged particle in the well-known nonuniform field of a current-carrying long straight wire, a variety of teaching/learning opportunities are described: 1) Brief review of a standard problem; 2) Vector analysis; 3) Dimensionless variables; 4) Coupled differential equations; 5) Numerical solutions.

  1. Estimated carrying capacity for cattle competing with prairie dogs and forage utilization in western South Dakota

    Science.gov (United States)

    Daniel W. Uresk; Deborah D. Paulson

    1988-01-01

    Carrying capacities for cattle competing with black-tailed prairie dogs (Cynomys ludovicianus) were estimated by a linear programming technique for management of cool-season grasses in western South Dakota. Forage utilization was allowed to range from 20% to 80%. Under management for cool-season grasses (western wheatgrass (Agropyron smithii...

  2. Influence and selection processes in weapon carrying during adolescence : The roles of status, aggression, and vulnerability

    NARCIS (Netherlands)

    Dijkstra, Jan; Lindenberg, Siegwart; Veenstra, Rene; Steglich, Christian; Isaacs, Jenny; Card, Noel A.; Hodges, Ernest V. E.

    The role of peers in weapon carrying (guns, knives, and other weapons) inside and outside the school was examined in this study. Data stem from a longitudinal study of a high-risk sample of male students (7th to 10th grade; N = 167) from predominantly Hispanic low-socio-economic-status schools in

  3. Is carry-over of grass biomass between years important in ...

    African Journals Online (AJOL)

    We show that the size of areas burned in three southern African parks is dominated by the amount of rainfall in the immediately preceding summer. Considering mean rainfall from two years previous changes r2 values by <20%. We interpret this to suggest that carry-over of grass from one fire year to another is relatively ...

  4. Carrying Position Independent User Heading Estimation for Indoor Pedestrian Navigation with Smartphones

    Directory of Open Access Journals (Sweden)

    Zhi-An Deng

    2016-05-01

    Full Text Available This paper proposes a novel heading estimation approach for indoor pedestrian navigation using the built-in inertial sensors on a smartphone. Unlike previous approaches constraining the carrying position of a smartphone on the user’s body, our approach gives the user a larger freedom by implementing automatic recognition of the device carrying position and subsequent selection of an optimal strategy for heading estimation. We firstly predetermine the motion state by a decision tree using an accelerometer and a barometer. Then, to enable accurate and computational lightweight carrying position recognition, we combine a position classifier with a novel position transition detection algorithm, which may also be used to avoid the confusion between position transition and user turn during pedestrian walking. For a device placed in the trouser pockets or held in a swinging hand, the heading estimation is achieved by deploying a principal component analysis (PCA-based approach. For a device held in the hand or against the ear during a phone call, user heading is directly estimated by adding the yaw angle of the device to the related heading offset. Experimental results show that our approach can automatically detect carrying positions with high accuracy, and outperforms previous heading estimation approaches in terms of accuracy and applicability.

  5. Could Tourism Carrying Capacity be a useful tool for adapting to climate change?

    OpenAIRE

    Magnan , Alexandre; Duvat , Virginie

    2010-01-01

    International audience; This paper focuses on coastal areas and aims at providing a first reflection on the potential role of the tourism carrying capacity approach (TCC) in the context of adaptation to climate change (ACC). Could TCC be seen as a pragmatic and already available tool for starting implementing ACC?

  6. Identification and characterization of a Zea mays line carrying a transposon-tagged ENOD40

    NARCIS (Netherlands)

    Compaan, B.; Ruttink, T.; Albrecht, C.; Meeley, R.; Bisseling, T.; Franssen, H.G.J.M.

    2003-01-01

    In Zea mays, two ENOD40 homologous were identified that show only 30% of sequence homology to each other. We identified line e40-mum1 carrying a Mu transposon inserted in ZmENOD40-1, the maize gene that has the highest homology to leguminous ENOD40. The insertion causes a dramatic reduction of the

  7. From "Thoughts and Prayers" to Practice: Narratives of Faculty Sensemaking during Campus-Carry Policy Enactment

    Science.gov (United States)

    Cradit, Nathaniel W.

    2017-01-01

    The 2007 mass shooting at Virginia Tech is one part of a decades-long increase in the frequency of gun violence on U.S. college and university campuses (Drysdale, Modzeleski, & Simons, 2010; Ferraro, 2015). The events at Virginia Tech also served as a catalyst for the spread of so-called "campus-carry" laws, or acts of state policy…

  8. Utilization of Wheat Offal-Carried Pineapple Waste in the Diet of ...

    African Journals Online (AJOL)

    Utilization of Wheat Offal-Carried Pineapple Waste in the Diet of West African Dwarf (WAD) Goats. ... Although, the analysis of blood cells (red blood cell, white blood and packed cell volume counts) were significantly different (p<0.05) among the goats fed experimental diets, the counts fell within the normal physiological ...

  9. Ecological Footprints and Appropriated Carrying Capacity: Measuring the Natural Capital Requirements of the Human Economy.

    Science.gov (United States)

    Ress, William E.; Wackernagel, Mathis

    1996-01-01

    Contrasts conventional economic rationality with economic principles. Develops an empirical approach based on a reinterpretation of carrying capacity that can account for technological advances and trade. Discusses the necessity of diverting much of the present consumption to investment in the maintenance of natural capital stocks. (AIM)

  10. Proteinase 3 carries small unusual carbohydrates and associates with αlpha-defensins

    DEFF Research Database (Denmark)

    Zoega, Morten; Ravnsborg, Tina; Højrup, Peter

    2012-01-01

    with carbohydrates at Asn 102 and 147 carrying unusual small moieties indicating heavy processing. Mass spectrometric analysis and immuno blotting revealed strong association of highly purified PR3 with α-defensins and oligomers hereof. Irreversible inhibition of PR3 by α1-antitrypsin did not affect its association...

  11. 36 CFR 5.4 - Commercial passenger-carrying motor vehicles.

    Science.gov (United States)

    2010-07-01

    ... motor vehicles. 5.4 Section 5.4 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.4 Commercial passenger-carrying motor vehicles. (a) The commercial transportation of passengers by motor vehicles except as authorized under a contract or...

  12. Who Carries the National Flag?: The Politics of Cultural Identity in the Increasingly Multicultural Greek School

    Science.gov (United States)

    Mattheou, Dimitrios; Roussakis, Yiannis; Theocharis, Dimitris

    2006-01-01

    The change in the composition of the school population as a result of the extensive influx of immigrants in Greece has brought in a recurrent controversy on the issue of allowing non-Greek citizen to carry the national flag, the Greek's most cherished national emblem, as a reward for an excellent school performance. When a state legislator, many…

  13. 48 CFR 19.707 - The Small Business Administration's role in carrying out the program.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false The Small Business Administration's role in carrying out the program. 19.707 Section 19.707 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 19.707 The Small Busines...

  14. Successfully carrying out complex learning tasks through guiding teams’ qualitative and quantitative reasoning

    NARCIS (Netherlands)

    Slof, Bert; Erkens, Gijsbert; Kirschner, Paul A.; Janssen, Jeroen; Jaspers, Jos

    2011-01-01

    Slof, B., Erkens, G., Kirschner, P. A., Janssen, J., & Jaspers, J. G. M. (2012). Successfully carrying out complex learning tasks through guiding teams' qualitative and quantitative reasoning. Instructional Science, 40, 623-643. DOI: 10.1007/s11251-011-9185-2

  15. Test-retest reliability of lifting and carrying in a 2-day functional capacity evaluation

    NARCIS (Netherlands)

    Reneman, MF; Dijkstra, PU; Westmaas, M; Goeken, LNH; Göeken, L.N.H.

    2002-01-01

    The objectives of this study were to establish test-retest reliability of lifting and carrying of a functional capacity evaluation (FCE) on two consecutive days and to verify the need for a 2-day protocol. A cohort of 50 patients (39 men, 11 women) with nonspecific low back pain were evaluated using

  16. High-level methodology for carrying out combined red and blue teams

    CSIR Research Space (South Africa)

    Veerasamy, N

    2009-12-01

    Full Text Available This paper proposes a combined Red and Blue Team Methodology to guide the process of carrying out such security auditing and penetration testing tasks. Red and Blue Teams consist of various security auditing and penetration testing tasks which serve...

  17. Status clarification and disposal of Carrière’s ivy names

    Directory of Open Access Journals (Sweden)

    Severiano Nava, Herminio

    2016-06-01

    Full Text Available Carrière in 1890 published 34 names and 33 descriptions of a collection of live ivy plants. In this article we present the analysis of his work from a nomenclatural perspective. As a result, the legitimacy and even the validity of specific and some of the infraspecific names published in the work are questioned. In addition to this, and considering the benefits on keeping the nomenclatural stability, Hedera azorica Carrière, is proposed as a nomen conservandum.Carrière en 1890 publicó 34 nombres y 33 descripciones de una colección de plantas vivas de hiedra. En este artículo se presenta el análisis de su obra desde una perspectiva nomenclatural. Como resultado, la legitimidad e incluso la validez de algunos de los nombres específicos e infraespecíficos publicados en la obra son puestas en tela de juicio. Además, teniendo en cuenta los beneficios de mantener la estabilidad nomenclatural, Hedera azorica Carrière se propone como nomen conservandum.

  18. Robust interferometer for the routing of light beams carrying orbital angular momentum

    CSIR Research Space (South Africa)

    Lavery, MPJ

    2011-09-01

    Full Text Available The authors have developed an interferometer requiring only minimal angular alignment for the routing of beams carrying orbital angular momentum. The Mach–Zehnder interferometer contains a Dove prism in each arm where each has a mirror plane around...

  19. Effect of Gamma Radiation on Amino Acid Based Vesicle Carrying Radiosensitizer

    International Nuclear Information System (INIS)

    Nur Ratasha Alia Mohd Rosli; Faizal Mohamed; Muhammad Amir Syafiq Mohd Sah; Irman Abdul Rahman

    2014-01-01

    Vesicles has been developed and studied to be used as a medium to transport radiosensitizer in treating cancer cells by increasing its sensitivity effectively towards the radiation given during radiotherapy. This study was conducted to investigate the effect of gamma radiation on amino acid-based vesicle carrying radiosensitizer. Amino acid based vesicles carrying radiosensitizer were synthesized using sonication method with sodium N-lauroylsarcosinate hydrate and decanol being the primary surfactant, while hydrogen peroxide and sodium hyaluronate as the encapsulated radiosensitizer. The synthesized vesicle was then irradiated at radiation doses equivalent to those given during radiotherapy. Irradiated vesicle carrying radiosensitizer were then characterized using Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and Polarized Light Microscope. Results obtained shows that there were no significant changes in morphology and molecular conformation of the synthesized vesicle after irradiation. Even at higher radiation dose of 100 Gray and 200 Gray, the results remained unchanged. This indicates that the synthesized vesicle carrying radiosensitizer is morphologically and spectroscopically stable even at high radiation doses. (author)

  20. Specific experiments carried out in Germany in order to demonstrate the safety of existing structures

    International Nuclear Information System (INIS)

    Krutzik, Norbert

    2002-01-01

    Specific experiments are carried out in Germany in order to demonstrate the safety of existing NPPs. HDR research program includes operational loads testing (pressure test, pressure and temperature test, thermal shock, fatigue); extreme loads (earthquake, aircraft crash, external explosion); internal emergency loads (blowdown, hydrogen combustion, fire, thermal shock, water hammer, condensation loads)

  1. Prescription Audit carried out at the Pharmacy Practice Centre of the ...

    African Journals Online (AJOL)

    A retrospective descriptive study was carried out from June to November 2004 in a retail pharmacy situated at the School of Pharmacy, University of Nairobi within the Kenyatta National Hospital complex. The objective was to evaluate prescribing habits and to determine the frequency of prescribing of commonly used drug ...

  2. CEC paper on an overview of activities carried out by the WGCS

    International Nuclear Information System (INIS)

    Guinovart, J.

    1994-01-01

    The paper overviews the activities carried out by the WGCS (Working Group Codes and Standards). Summary of conclusions, established in some reports which were finalized in 1992, are outlined for three sub-groups of activity. Two tables summarize the LWR 1992-93 programs are attached. 2 tabs

  3. Like an eagle carries its young | Wünch | HTS Teologiese Studies ...

    African Journals Online (AJOL)

    The picture of an eagle carrying its young on its wings (Dt 32:11) is a powerful and encouraging image of trust and security in God. It is particularly relevant for Western culture, where the eagle is a prominent symbol of power and strength. In recent years, though, the translation of the Hebrew term נשֶֶׁר as 'eagle' has come ...

  4. Carrying large fuel loads during sustained bird flight is cheaper than expected

    NARCIS (Netherlands)

    Kvist, A; Lindström, A; Green, M; Piersma, T.; Visser, G.H.

    2001-01-01

    Birds on migration alternate between consuming fuel stores during flights and accumulating fuel stores during stopovers. The optimal timing and length of flights and stopovers for successful migration depend heavily on the extra metabolic power input (fuel use) required to carry the fuel stores

  5. In vivo characteristics of targeted drug-carrying filamentous bacteriophage nanomedicines

    Directory of Open Access Journals (Sweden)

    Vaks Lilach

    2011-12-01

    Full Text Available Abstract Background Targeted drug-carrying phage nanomedicines are a new class of nanomedicines that combines biological and chemical components into a modular nanometric drug delivery system. The core of the system is a filamentous phage particle that is produced in the bacterial host Escherichia coli. Target specificity is provided by a targeting moiety, usually an antibody that is displayed on the tip of the phage particle. A large drug payload is chemically conjugated to the protein coat of the phage via a chemically or genetically engineered linker that provides for controlled release of the drug after the particle homed to the target cell. Recently we have shown that targeted drug-carrying phage nanomedicines can be used to eradicate pathogenic bacteria and cultured tumor cells with great potentiation over the activity of the free untargeted drug. We have also shown that poorly water soluble drugs can be efficiently conjugated to the phage coat by applying hydrophilic aminoglycosides as branched solubility-enhancing linkers. Results With an intention to move to animal experimentation of efficacy, we tested anti-bacterial drug-carrying phage nanomedicines for toxicity and immunogenicity and blood pharmacokinetics upon injection into mice. Here we show that anti-bacterial drug-carrying phage nanomedicines that carry the antibiotic chloramphenicol conjugated via an aminoglycoside linker are non-toxic to mice and are greatly reduced in immunogenicity in comparison to native phage particles or particles to which the drug is conjugated directly and are cleared from the blood more slowly in comparison to native phage particles. Conclusion Our results suggest that aminoglycosides may serve as branched solubility enhancing linkers for drug conjugation that also provide for a better safety profile of the targeted nanomedicine.

  6. Variation in local carrying capacity and the individual fate of bacterial colonizers in the phyllosphere

    Science.gov (United States)

    Remus-Emsermann, Mitja N P; Tecon, Robin; Kowalchuk, George A; Leveau, Johan H J

    2012-01-01

    Using a phyllosphere model system, we demonstrated that the term ‘carrying capacity', as it is commonly used in microbial ecology, needs to be understood as the sum of many ‘local carrying capacities' in order to better explain and predict the course and outcome of bacterial colonization of an environment. Using a green fluorescent protein-based bioreporter system for the quantification of reproductive success (RS) in individual Erwinia herbicola cells, we were able to reconstruct the contribution of individual immigrants to bacterial population sizes on leaves. Our analysis revealed that plant foliage represents to bacteria an environment where individual fate is determined by the local carrying capacity of the site where an immigrant cell lands. With increasing inoculation densities, the RS of most immigrants declined, suggesting that local carrying capacity under the tested conditions was linked to local nutrient availability. Fitting the observed experimental data to an adapted model of phyllosphere colonization indicated that there might exist three types of sites on leaves, which differ in their frequency of occurrence and local carrying capacity. Specifically, our data were consistent with a leaf environment that is characterized by few sites where individual immigrants can produce high numbers of offspring, whereas the remainder of the leaf offered an equal number of sites with low and medium RS. Our findings contribute to a bottom–up understanding of bacterial colonization of leaf surfaces, which includes a quantifiable role of chance in the experience at the individual level and in the outcome at the population level. PMID:22258099

  7. Nanoemulsions and nonwoven fabrics carrying AgNPs: antibacterial but may be cytotoxic.

    Science.gov (United States)

    Moghtader, Farzaneh; Salouti, Mojtaba; Türk, Mustafa; Pişkin, Erhan

    2014-12-01

    Abstract The aim of this study is to prepare nonwoven fabrics carrying silver nanoparticles (AgNPs), and to investigate their antibacterial activities and cytotoxicities in parallel. AgNPs were impregnated from their nanoemulsions onto two commercially available nonwoven fabrics: pure-cotton fabrics (PCF) and polyester/viscous fabrics (PVF), by a simple adsorption (dipping) and were then heat stabilized. PCF exhibited stronger antibacterial effects on both Staphylococcus aureus and Escherichia coli. In-vitro cell culture studies demonstrated that AgNPs nanoemulsions and also fabrics carrying them were cytotoxic on L929-fibroblasts in all concentrations used here (6.25-400 ppm) in different extends. Only the fabrics loaded with AgNPs using nanoemulsion with the lowest concentration of 6.25 ppm exhibited low cytotoxicity but were still antibacterial.

  8. Chemical composition shape form and size of suspended solids in the atmosphere carried by rain water

    International Nuclear Information System (INIS)

    Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la

    2001-01-01

    The interest of this work is to know about shape form, size and chemical composition of the suspended solids in the atmosphere of Toluca city and which are carried by the rains. The harvest of the samples was carried out during january to november 1999. The separation of the particulate matter from the rain water was realized through centrifugation. The solids were analysed by Scanning Electron Microscopy to know the shape form and size and the chemical composition was determined by X-ray dispersive energy in general form and of some particles individually analysed. The p H was measured to the solutions and the quantification of some dissolved ions by the Icp technique was realized. The results of the solids showed C, O, Na, Mg, Al, Si, S, P, K, Ca, Ti and Fe. Moreover they present sizes which varying from a ten of nanometers until some tens of microns. (Author)

  9. Analysis on economic carrying capacity index of pig breeding in China

    Science.gov (United States)

    Leng, Bi-Bin; Liu, Jia-Ling; Xu, Yue-Feng

    2017-08-01

    In this paper, factor analysis method was employed to analyze and calculate the Gross Domestic Product (GDP) per capita in the last decade, the proportion of research and experiment development (R&D) expenditure equivalent to GDP, urban and rural residents’ pork consumption and explored the scale of Chinese pig breeding on economic carrying capacity index. The result showed that the growth of GDP had led to better techniques and higher field investment, and stronger support like science and technology from the government provided good conditions for large scale of pig breeding. Besides, the substantial increase of pork consumption between rural and urban residents has contributed to the pig breeding in large scale. As a result, the economic carrying capacity index in Chinese pig farming is on the rise.

  10. Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia

    Science.gov (United States)

    Zhang, Liye; Chung, ShanShan

    2015-12-01

    This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

  11. Carrying pharyngeal of Streptococcus pyogenes and sensitivity profiles in schoolchild from Cartagena

    Directory of Open Access Journals (Sweden)

    Lucy Margarita Villafañe-Ferrer

    2015-07-01

    Full Text Available To determine the frequency of carrying pharyngeal of Streptococcus pyogenes and their sensitivity profiles in schoolchildren from Cartagena. Analytical cross-sectional study, the sample was composed by 131 children. Strains of Streptococcus pyogenes were identified using conventional methods. Antibiotic sensitivity was determined the Kirby-Bauer methods. A questionnaire was applied in order to identify risk factors associated.19,8% of children were carriers of bacterium. 26 isolates of Streptococcus pyogenes were obtained. To evaluate the sensitivity were found strains sensible to ceftriaxone and erytrhomycin (84,6% each one. 23,1% (6/26 0f isolates were resistant to ampicillin. It not was found association between carrying pharyngeal of Streptococcus pyogenes and risk factors (p>0,05. It were found resistant strains to antibiotics considered of first election for therapy of infectious diseases produced by this bacterium.

  12. The development of Coke Carried-Heat Gasification Coal-Fired Combined Cycle

    Science.gov (United States)

    Zhao, Li; Xu, Xiangdong

    1999-12-01

    Carried-Heat Partial Gasification Combined cycle is a novel combined cycle which was proposed by Thermal Engineering Department of Tsinghua University in 1992. The idea of the system comes from the situation that the efficiency of the power plants in China is much lower than that of the advanced countries, but the coal consumption is much higher, which brings about the waste of primary energy resources and the pollution of the environment. With the deep study of the gasification technology, Coke Carried-Heat Gasification Coal-Fired Combined Cycle, as the improved system, came into birth in 1996 based on the partial gasification one. At the end of 1997, a new cycle scheme similar to IGCC was created. This paper focuses on several classes combined cycle put forward by Tsinghua University, depending on the plant configuration and carbon conversion, making the solution a viable and attractive option for efficient coal utilization.

  13. University presidents' perceptions and practice regarding the carrying of concealed handguns on college campuses.

    Science.gov (United States)

    Price, James H; Thompson, Amy; Khubchandani, Jagdish; Dake, Joseph; Payton, Erica; Teeple, Karen

    2014-01-01

    To assess the perceptions and practices of a national sample of college and university presidents regarding their support for concealed handguns being carried on college campuses. The sample for this study consisted of a national random sample of 900 college or university presidents. In the spring of 2013, a 3-wave mailing procedure was used to ensure an adequate response rate to a valid and reliable questionnaire. The response rate was 46%, more than what was needed based on the power analysis. The vast majority (95%) of respondents were not supportive of carrying concealed handguns on campuses. They perceived there to be more disadvantages than advantages to handguns on campus. However, college administrators were not focused enough on the primary prevention of campus firearm trauma. The findings of this study suggest a number of activities that could be implemented to enhance safety on college and university campuses.

  14. EVALUATION OF SHEAR CARRIED BY STEEL FIBERS OF REINFORCED CONCRETE BEAMS USING TENSION SOFTENING CURVES

    Science.gov (United States)

    Jongvivatsakul, Pitcha; Watanabe, Ken; Matsumoto, Koji; Niwa, Junichiro

    The aim of this paper is to propose the method for evaluating the shear carried by steel fibers of reinforced concrete with steel fibers (RSF) beams. Ten RSF beams with various steel fiber volume fraction, stirrup ratio and specimen size were tested by a four-point bending test. The crack surface displacement was examined by the image analysis. Length of the diagonal crack was measured. The tension softening curves were used to calculate the stress transferred across the diagonal crack. The contribution of steel fibers on the shear resistance of RSF beams has been investigated based on the fracture mechanics. The shear carried by steel fibers calculated from the proposed method showed good agreement with experimental values.

  15. Nonlinear Oscillations of Elastic Curved Plate Carried to the Associated Masses System

    Science.gov (United States)

    Sysoyev, O. Ye; Dobryshkin, A. Yu; Naing, N. S.

    2017-11-01

    Curved plates are used in many spheres of our life. Often curved plates have an articulated support. Often, the operation of such structures is associated with fluctuations as well as with the systems of attached masses. The vibrations of such structures have not been fully studied yet. In the laboratory of building structures of Komsomolsk-on-Amur State Technical University a test bench was prepared for testing curved plates hinged at the edges and carrying an attached mass or a system of attached masses. The attached mass is represented by a sensor fixed to the body of a curved plate carrying an attached mass. Experimental and theoretical data correlate with each other. Minimal discrepancies were obtained with the minimum attached mass and the maximum discrepancies at the maximum investigated attached mass. Theoretical calculations were performed using the known equations of plate oscillations.

  16. Clonal spread of blaOXA-72-carrying Acinetobacter baumannii sequence type 512 in Taiwan.

    Science.gov (United States)

    Kuo, Han-Yueh; Hsu, Po-Jui; Chen, Jiann-Yuan; Liao, Po-Cheng; Lu, Chia-Wei; Chen, Chang-Hua; Liou, Ming-Li

    2016-07-01

    This is the first report to show an insidious outbreak of armA- and blaOXA-72-carrying Acinetobacter baumannii sequence type 512 (ST512) at a study hospital in northern Taiwan. Multilocus sequence typing revealed that this was a ST512 clone. All of the isolates with ST512 carried a novel 12,056-bp repGR2 in combination with a repGR12-type plasmid. This plasmid, designated pAB-ML, had one copy of the blaOXA-72 gene that was flanked by XerC/XerD-like sites and conferred resistance to carbapenems. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  17. Investigation of diversity of plasmids carrying the blaTEM-52 gene

    DEFF Research Database (Denmark)

    Bielak, Eliza Maria; Bergenholtz, Rikke D.; Jørgensen, Mikael Skaanning

    2011-01-01

    OBJECTIVES: To investigate the diversity of plasmids that carry blaTEM-52 genes among Escherichia coli and Salmonella enterica originating from animals, meat products and humans. METHODS: A collection of 22 blaTEM-52-encoding plasmids was characterized by restriction fragment length polymorphism...... of self-transfer to a plasmid-free E. coli recipient. CONCLUSIONS: The blaTEM-52 gene found in humans could have been transmitted on transferable plasmids originating from animal sources. Some of the blaTEM-52 plasmids carry replicons that differ from the classical ones. Two novel replicons were detected...... (RFLP), replicon typing (by PCR or replicon sequencing), susceptibility testing, assessment of plasmid ability to self-transfer by conjugation and typing of the genetic environment of the blaTEM-52 gene. Detected IncI1 plasmids underwent further plasmid multilocus sequence typing. RESULTS: RFLP profiles...

  18. Transfer of stem cells carrying engineered chromosomes with XY clone laser system.

    Science.gov (United States)

    Sinko, Ildiko; Katona, Robert L

    2011-01-01

    Current transgenic technologies for gene transfer into the germline of mammals cause a random integration of exogenous naked DNA into the host genome that can generate undesirable position effects as well as insertional mutations. The vectors used to generate transgenic animals are limited by the amount of foreign DNA they can carry. Mammalian artificial chromosomes have large DNA-carrying capacity and ability to replicate in parallel with, but without integration into, the host genome. Hence they are attractive vectors for transgenesis, cellular protein production, and gene therapy applications as well. ES cells mediated chromosome transfer by conventional blastocyst injection has a limitation in unpredictable germline transmission. The demonstrated protocol of laser-assisted microinjection of artificial chromosome containing ES cells into eight-cell mouse embryos protocol described here can solve the problem for faster production of germline transchromosomic mice.

  19. Studies on solid-state physics carried out with the Saclay reactor (1962)

    International Nuclear Information System (INIS)

    Herpin, A.

    1962-01-01

    This paper deals only with solid-state physics experiments carried out on outgoing beams: rather than giving a general review of the work performed, if refers to only a few of the most important studies or those nearest completion. These are being made with the experimental beams of the two Saclay reactors EL-2, with a central flux of 10 13 n/cm 2 , and - since 1958 - EL-3, whose central flux is equal ta 10 14 n/cm 2 . The experiments are being carried out by two separate groups of physicists, employing different techniques, namely neutron diffraction using a crystal spectrometer, and inelastic scattering using a time-of-flight spectrometer. (author) [fr

  20. Studies on Cup Anemometer Performances Carried out at IDR/UPM Institute. Past and Present Research

    Directory of Open Access Journals (Sweden)

    Elena Roibas-Millan

    2017-11-01

    Full Text Available In the present work, the research derived from a wide experience on cup anemometer calibration works at IDR/UPM Institute (Instituto Universitario de Microgravedad “Ignacio Da Riva” is summarized. This research started in 2008, analyzing large series of calibrations, and is focused on two main aspects: (1 developing a procedure to predict the degradation level of these wind sensors when working on the field and (2 modeling cup anemometer performances. The wear and tear level of this sensor is evaluated studying the output signal and its main frequencies through Fourier analysis. The modeling of the cup anemometer performances is carried out analyzing first the cup aerodynamics. As a result of this process, carried out through several testing and analytical studies since 2010, a new analytical method has been developed. This methodology might represent an alternative to the classic approach used in the present standards of practice such as IEC 64000-12.