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Sample records for ganglionar por rickettsia

  1. Rickettsiosis cutáneo ganglionar por Rickettsia conorii en el Uruguay Cutaneous-ganglionar rickettsiosis by Rickettsia conorii in Uruguay

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    Ismael A. Conti-Diaz; Ivonne Rubio; Raúl E. Somma Moreira; Graciela Pérez Bórmida

    1990-01-01

    Se refieren 3 casos autóctonos de rickettsiosis cutáneo ganglionar trasmitidos por garrapatas de perros (Amblyomma maculatum, en uno de ellos) en el Uruguay. Dos de los 3 casos fueron seguramente provocados por Rickettsia conorii de acuerdo a los resultados de la reacción específica de inmunofluorescencia indirecta - IgM, anti R. conorii. Se incluye un tercer paciente no estudiado con tal técnica, por la similitud clínico-epidemiológica, la reactividad del suero frente al Proteus OX 19 y la r...

  2. Rickettsiosis cutáneo ganglionar por Rickettsia conorii en el Uruguay Cutaneous-ganglionar rickettsiosis by Rickettsia conorii in Uruguay

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    Ismael A. Conti-Diaz

    1990-10-01

    Full Text Available Se refieren 3 casos autóctonos de rickettsiosis cutáneo ganglionar trasmitidos por garrapatas de perros (Amblyomma maculatum, en uno de ellos en el Uruguay. Dos de los 3 casos fueron seguramente provocados por Rickettsia conorii de acuerdo a los resultados de la reacción específica de inmunofluorescencia indirecta - IgM, anti R. conorii. Se incluye un tercer paciente no estudiado con tal técnica, por la similitud clínico-epidemiológica, la reactividad del suero frente al Proteus OX 19 y la rápida respuesta a la tetraciclina. La no descripción previa de la rickettsiosis por R. conorii en forma autóctona en el área de las Américas confiere especial interés a la comunicación, recomendándose la búsqueda de la afección en otros países de la región.Three autochthonous cases of cutaneous-ganglionar rickettsiosis transmitted by dogs ticks (Amblyomma maculatum in one of them are reported. Two of the three cases were undoubtely produced by Rickettsia conorii according to the results of the specific indirect immunofluorescence technique IEF-IgM anti R. conorii. A third case is included due to the clinical epidemiological similarity, the positive serum reactivity with Proteus O x 19 and the rapid response to tetracycline. Autochthonous rickettsiosis by R. conorii has not been previously registered in the American area what confers special interest to this communication. The search of the disease in the other countries of the region is suggested.

  3. Clinical and laboratorial evidence of Rickettsia felis infections in Latin America Evidência clínica e laboratorial de infecções por Rickettsia felis na América Latina

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    Márcio Antônio Moreira Galvão

    2004-06-01

    Full Text Available After the discovery and initial characterization of Rickettsia felis in 1992 by Azad and cols, and the subsequent first description of a human case of infection in 1994, there have been two communications of human rickettsiosis cases caused by Rickettsia felis in Latin America. The first one was published in 2000 by Zavala-Velazquez and cols in Mexico. In 2001 Raoult and cols described the occurrence of two human cases of Rickettsia felis rickettsiosis in Brazil. In the present discussion these two articles were compared and after the description of the principal signs and symptoms, it was concluded that more studies are needed with descriptions of a greater number of patients to establish the true frequency of the clinical signs and symptoms present in Rickettsia felis rickettsiosis.Depois da descoberta e caracterização inicial da Rickettsia felis em 1992 por Azad e cols, e à descrição subseqüente do primeiro caso de infecção humana em 1994, houveram duas comunicações de rickettsioses causadas por Rickettsia felis na América Latina. A primeira foi feita por Zavala-Velazquez e cols em 2000 no México. Em 2001, Raoult e cols descreveram a ocorrência de dois casos humanos de rickettsiose por Rickettsia felis no Brasil. Na presente discussão, esses dois artigos foram comparados, e depois da descrição dos principais sinais e sintomas, conclui-se que outros estudos são necessários, com a participação de um maior número de pacientes, para se estabelecer a verdadeira freqüência dos sinais clínicos e sintomas presentes nas rickettsioses por Rickettsia felis.

  4. 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.

  5. Patogénesis de las infecciones producidas por rickettsias en las Américas

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    Gustavo Valbuena

    2010-04-01

    Full Text Available Colombia fue el segundo país en reportar rickettsiosis en Latino América (en el año de 1.937; el primero fue Brasil. Estos primeros casos reportados correspondieron a un brote de fiebre de las Montañas Rocosas que ocurrió en la localidad de Tobia, Cundinamarca (1. Además, hasta mediados de los años 40 del siglo pasado, el tifo epidémico (causado por R. prowazekii era endémico en muchas ciudades de Colombia, incluyendo Bogotá.

  6. 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

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    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

  7. Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel.

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    Waner, Trevor; Keysary, Avi; Eremeeva, Marina E; Din, Adi Beth; Mumcuoglu, Kosta Y; King, Roni; Atiya-Nasagi, Yafit

    2014-05-01

    DNA of several spotted fever group rickettsiae was found in ticks in Israel. The findings include evidence for the existence of Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel. The DNA of R. africae was detected in a Hyalomma detritum tick from a wild boar and DNA of C. Rickettsia barbariae was detected in Rhipicephalus turanicus and Rhipicephalus sanguineus collected from vegetation. The DNA of Rickettsia massiliae was found in Rh. sanguineus and Haemaphysalis erinacei, whereas DNA of Rickettsia sibirica mongolitimonae was detected in a Rhipicephalus (Boophilus) annulatus. Clinicians should be aware that diseases caused by a variety of rickettsiae previously thought to be present only in other countries outside of the Middle East may infect residents of Israel who have not necessarily traveled overseas. Furthermore, this study reveals again that the epidemiology of the spotted fever group rickettsiae may not only involve Rickettsia conorii but may include other rickettsiae.

  8. Ganglionar nervous cells and telocytes in the pancreas of Octodon degus: extra and intrapancreatic ganglionar cells and telocytes in the degus.

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    Bosco, Cleofina; Díaz, Eugenia; Gutiérrez, Rodrigo; González, Jaime; Pérez, Johanna

    2013-10-01

    This study shows for the first time the presence of intra and extrapancreatic ganglionar neurons and telocytes in Octodon degus such as those described in human and guinea pig pancreas. Pancreatic ganglionar neurons were identified by their histological characteristics as well as their positive immunostaining with mouse anti-human neuron specific enolase (NSE) antibody. Somatostatin secreting delta cells (D cells) in the islets of Langerhans were identified by positive immunostaining with rabbit antihuman polyclonal somatostatin antibody. Electron microscopy evidenced the presence of some unmyelinated axons in the interlobular spaces or septa, usually located adjacent to blood vessels and the exocrine epithelial ducts. The presence of telocytes with at least 2 telopodes was observed in the interlobular space, frequently in close spatial relationship with blood vessels and nerve endings. Telocytes were often observed in the vicinity or even in close proximity with both secretory acini and exocrine epithelial ducts and regulatory nerves and blood vessel apparatuses. A possible framework has been put forward within which such structures might contribute to elicit physiological responses in the pancreas. Further studies of synaptic interactions within and between pancreatic neuron cells are needed to help clarify the morphological results reported here. A broad overview of the field of neurogastroenterology with focus on the pancreas of O. degus related to the enteric nervous system (ENS) is provided in order to help design future studies on the connections of specific neurons forming pancreatic pathways, their neurotransmission processes and how disruption of these pathways may contribute to pancreatic disease.

  9. Tropism and pathogenicity of rickettsiae.

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    Uchiyama, Tsuneo

    2012-01-01

    Rickettsiae are obligate intracellular parasitic bacteria that cause febrile exanthematous illnesses such as Rocky Mountain spotted fever, Mediterranean spotted fever, epidemic, and murine typhus, etc. Although the vector ranges of each Rickettsia species are rather restricted; i.e., ticks belonging to Arachnida and lice and fleas belonging to Insecta usually act as vectors for spotted fever group (SFG) and typhus group (TG) rickettsiae, respectively, it would be interesting to elucidate the mechanisms controlling the vector tropism of rickettsiae. This review discusses the factors determining the vector tropism of rickettsiae. In brief, the vector tropism of rickettsiae species is basically consistent with their tropism toward cultured tick and insect cells. The mechanisms responsible for rickettsiae pathogenicity are also described. Recently, genomic analyses of rickettsiae have revealed that they possess several genes that are homologous to those affecting the pathogenicity of other bacteria. Analyses comparing the genomes of pathogenic and non-pathogenic strains of rickettsiae have detected many factors that are related to rickettsial pathogenicity. It is also known that a reduction in the rickettsial genome has occurred during the course of its evolution. Interestingly, Rickettsia species with small genomes, such as Rickettsia prowazekii, are more pathogenic to humans than those with larger genomes. This review also examines the growth kinetics of pathogenic and non-pathogenic species of SFG rickettsiae (SFGR) in mammalian cells. The growth of non-pathogenic species is restricted in these cells, which is mediated, at least in part, by autophagy. The superinfection of non-pathogenic rickettsiae-infected cells with pathogenic rickettsiae results in an elevated yield of the non-pathogenic rickettsiae and the growth of the pathogenic rickettsiae. Autophagy is restricted in these cells. These results are discussed in this review. PMID:22737150

  10. Tropism and pathogenicity of rickettsiae

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    Tsuneo eUchiyama

    2012-06-01

    Full Text Available Rickettsiae are obligate intracellular parasitic bacteria that cause febrile exanthematous illnesses such as Rocky Mountain spotted fever, Mediterranean spotted fever, epidemic and murine typhus, etc. Although the vector ranges of each Rickettsia species are rather restricted; i.e., ticks belonging to Arachnida and lice and fleas belonging to Insecta usually act as vectors for spotted fever group and typhus group rickettsiae, respectively, it would be interesting to elucidate the mechanisms controlling the vector tropism of rickettsiae. This review discusses the factors determining the vector tropism of rickettsiae. In brief, the vector tropism of rickettsiae species is basically consistent with their tropism towards cultured tick and insect cells. The mechanisms responsible for rickettsiae pathogenicity are also described. Recently, genomic analyses of rickettsiae have revealed that they possess several genes that are homologous to those affecting the pathogenicity of other bacteria. Analyses comparing the genomes of pathogenic and nonpathogenic strains of rickettsiae have detected many factors that are related to rickettsial pathogenicity. It is also known that a reduction in the rickettsial genome has occurred during the course of its evolution. Interestingly, Rickettsia species with small genomes, such as Rickettsia prowazekii, are more pathogenic to humans than those with larger genomes. This review also examines the growth kinetics of pathogenic and nonpathogenic species of spotted fever group rickettsiae in mammalian cells. The growth of nonpathogenic species is restricted in these cells, which is mediated, at least in part, by autophagy. The superinfection of nonpathogenic rickettsiae-infected cells with pathogenic rickettsiae results in an elevated yield of the nonpathogenic rickettsiae and the growth of the pathogenic rickettsiae. Autophagy is restricted in these cells. These results are discussed in this review.

  11. Tropism and Pathogenicity of Rickettsiae

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    Tsuneo eUchiyama

    2012-01-01

    Rickettsiae are obligate intracellular parasitic bacteria that cause febrile exanthematous illnesses such as Rocky Mountain spotted fever, Mediterranean spotted fever, epidemic, and murine typhus, etc. Although the vector ranges of each Rickettsia species are rather restricted; i.e., ticks belonging to Arachnida and lice and fleas belonging to Insecta usually act as vectors for spotted fever group (SFG) and typhus group (TG) rickettsiae, respectively, it would be interesting to elucidate the ...

  12. Rickettsia spp. in Ticks, Poland

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    Chmielewski, Tomasz; Podsiadly, Edyta; Karbowiak, Grzegorz; Tylewska-Wierzbanowska, Stanislawa

    2009-01-01

    Ticks are recognized as the main vectors and reservoirs of spotted fever group rickettsiae. We searched for the most prevalent Rickettsia spp. in Poland and found R. slovaca and R. helvetica bacteria in ticks in southern and central Poland; R. raoulti was found in ticks in all parts of Poland.

  13. 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

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    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

  14. Immunoproteomic profiling of Rickettsia parkeri and Rickettsia amblyommii.

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    Pornwiroon, Walairat; Bourchookarn, Apichai; Paddock, Christopher D; Macaluso, Kevin R

    2015-09-01

    Rickettsia parkeri is an Amblyomma-associated, spotted fever group Rickettsia species that causes an eschar-associated, febrile illness in multiple countries throughout the Western Hemisphere. Many other rickettsial species of known or uncertain pathogenicity have been detected in Amblyomma spp. ticks in the Americas, including Rickettsia amblyommii, "Candidatus Rickettsia andeanae" and Rickettsia rickettsii. In this study, we utilized an immunoproteomic approach to compare antigenic profiles of low-passage isolates of R. parkeri and R. amblyommii with serum specimens from patients with PCR- and culture-confirmed infections with R. parkeri. Five immunoreactive proteins of R. amblyommii and nine immunoreactive proteins of R. parkeri were identified by matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry. Four of these, including the outer membrane protein (Omp) A, OmpB, translation initiation factor IF-2, and cell division protein FtsZ, were antigens common to both rickettsiae. Serum specimens from patients with R. parkeri rickettsiosis reacted specifically with cysteinyl-tRNA synthetase, DNA-directed RNA polymerase subunit alpha, putative sigma (54) modulation protein, chaperonin GroEL, and elongation factor Tu of R. parkeri which have been reported as virulence factors in other bacterial species. Unique antigens identified in this study may be useful for further development of the better serological assays for diagnosing infection caused by R. parkeri.

  15. Rickettsiae in Gulf Coast Ticks, Arkansas, USA

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    Trout, Rebecca; Steelman, C Dayton; Szalanski, Allen L.; Williamson, Phillip C

    2010-01-01

    To determine the cause of spotted fever cases in the southern United States, we screened Gulf Coast ticks (Amblyomma maculatum) collected in Arkansas for rickettsiae. Of the screened ticks, 30% had PCR amplicons consistent with Rickettsia parkeri or Candidatus Rickettsia amblyommii.

  16. Epidemiología de rickettsiosis por Rickettsia parkeri y otras especies emergentes o re-emergentes asociadas a la antropización en Latinoamérica

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    José M Venzal

    2013-07-01

    Full Text Available Se describe la importancia regional de Rickettsia parkeri y sus respectivos vectores. Se hace énfasis en los factores de antropización que favorecen la aparición de hospedadores alternativos para las garrapatas en los entornos domésticos y peridomésticos, generando modificaciones en la epidemiología del agente etiológico. También se menciona las modificaciones ecológicas que pueden favorecen el incremento de poblaciones de reservorios para las garrapatas incrementando el riesgo para el ser humano de sufrir enfermedades rickettsiales.

  17. Epidemiología de rickettsiosis por Rickettsia parkeri y otras especies emergentes o re-emergentes asociadas a la antropización en Latinoamérica

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    Venzal, José M.

    2013-01-01

    Se describe la importancia regional de Rickettsia parkeri y sus respectivos vectores. Se hace énfasis en los factores de antropización que favorecen la aparición de hospedadores alternativos para las garrapatas en los entornos domésticos y peridomésticos, generando modificaciones en la epidemiología del agente etiológico. También se menciona las modificaciones ecológicas que pueden favorecen el incremento de poblaciones de reservorios para las garrapatas incrementando el riesgo para el ser hu...

  18. Identificación de una nueva área de infección por Rickettsias del grupo typhi: estudio de un brote de tifus en Huánuco

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    Rosa Mostorino E

    2003-03-01

    Full Text Available Objetivos: Investigar un brote de síndrome febril en el distrito de Punchao mediante una evaluación clínica, laboratorial y entomológica para conocer los factores asociados a la aparición de dicho brote. Materiales y métodos: Debido al reporte de tres pacientes con cuadro clínico febril asociado a cefalea, mialgias y postración en la semana epidemiológica Nº41 del año 2000, procedentes del distrito de Punchao, Humalíes, Huánuco y ante la información de presentación inusual de pacientes febriles en la última semana en dicho lugar, se decidió investigar la naturaleza y características del brote. Se definió como caso a todo paciente con cuadro febril agudo y uno de estos síntomas: cefalea, mialgias o postración; procediéndose a la búsqueda activa de éstos y a la evaluación de presencia de anticuerpos para rickettsias en suero mediante inmunofluorescencia indirecta (IFI. Se capturaron roedores y se colectaron ectoparásitos en las viviendas (roedores, animales domésticos y humanos, a fin de identificar la presencia de Rickettsias en ellos mediante IFI, aislamiento o PCR. Resultados: No se logró el aislamiento del agente causal. Se evidenció circulación de la Rickettsia sp. (serología positiva tanto en humanos (en casos y en no casos como en roedores. Se evidenció mayor presencia de malos hábitos de aseo y condiciones inadecuadas de saneamiento básico en los casos (respecto a los no casos y una disminución de los casos luego del inicio de las medidas de control. Conclusiones: Las evidencias encontradas permitieron identificar un brote de tifus en Punchao, no pudiéndose determinar la especie involucrada debido a que no se aisló el agente causal.

  19. Electrotransformation and Clonal Isolation of Rickettsia Species.

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    Riley, Sean P; Macaluso, Kevin R; Martinez, Juan J

    2015-11-03

    Genetic manipulation of obligate intracellular bacteria of the genus Rickettsia is currently undergoing a rapid period of change. The development of viable genetic tools, including replicative plasmids, transposons, homologous recombination, fluorescent protein-encoding genes, and antibiotic selectable markers has provided the impetus for future research development. This unit is designed to coalesce the basic methods pertaining to creation of genetically modified Rickettsia. The unit describes a series of methods, from inserting exogenous DNA into Rickettsia to the final isolation of genetically modified bacterial clones. Researchers working towards genetic manipulation of Rickettsia or similar obligate intracellular bacteria will find these protocols to be a valuable reference.

  20. Valoración probabilística de un estadio ganglionar negativo tras cirugía de resección en el cáncer de colon. Repercusiones ante una alta probabilidad de error.

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    Martínez Ramos, David

    2008-01-01

    RESUMEN INTRODUCCIÓN. El estudio ganglionar en el cáncer de colon puede considerarse como una prueba diagnóstica, en la cual se obtiene un resultado binario (ganglios positivos o negativos). Utilizando el teorema de Bayes (TB) puede calcularse la probabilidad de afectación ganglionar cuando el estudio anatomopatológico ha resultado negativo, es decir, puede calcularse la probabilidad final de error (PFE) ante un estadio ganglionar negativo. En función de la PFE que se considere aceptable y...

  1. Rickettsia helvetica in Dermacentor reticulatus Ticks

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    Dobec, Marinko; Golubic, Dragutin; Punda-Polic, Volga; Kaeppeli, Franz; Sievers, Martin

    2009-01-01

    We report on the molecular evidence that Dermacentor reticulatus ticks in Croatia are infected with Rickettsia helvetica (10%) or Rickettsia slovaca (2%) or co-infected with both species (1%). These findings expand the knowledge of the geographic distribution of R. helvetica and D. reticulatus ticks.

  2. Identificación y caracterización de la población total de las células ganglionares de la retina en rata : nuevos métodos de trazado, expresión de melanopsina y de factores de transcripción Brn3:estudio de la respuesta neuronal y microglial a la axotomía y efecto del envejecimiento en la retina

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    Nadal Nicolás, Francisco Manuel

    2015-01-01

    Introducción La retina es parte del sistema nervioso central (SNC) y se localiza en la cara interna del globo ocular. Su función principal es la fototransducción de las ondas electromagnéticas del espectro de la luz visible en energía eléctrica. Esta función es realizada por los fotorreceptores (conos y bastones). Tras su procesamiento, la información llega a las células ganglionares de retina (CGR). Las CGR son las únicas neuronas aferentes de la retina y transmiten la información visual ...

  3. Seroprevalence of Rickettsia bellii and Rickettsia felis in dogs, São José dos Pinhais, State of Paraná, Brazil Soroprevalência de Rickettsia bellii e Rickettsia felis em cães, São José dos Pinhais, Paraná, Brasil

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    Fernanda Silva Fortes

    2010-12-01

    Full Text Available Brazilian spotted fever (BSF is a vector-borne zoonosis caused by Rickettsia rickettsii bacteria. Dogs can be host sentinels for this bacterium. The aim of the study was to determine the presence of antibodies against Rickettsia spp. in dogs from the city of São José dos Pinhais, State of Paraná, Southern Brazil, where a human case of BSF was first reported in the state. Between February 2006 and July 2007, serum samples from 364 dogs were collected and tested at 1:64 dilutions by indirect immunofluorescence assay (IFA against R. rickettsii and R. parkeri. All sera that reacted at least to one of Rickettsia species were tested against the six main Rickettsia species identified in Brazil: R. rickettsii, R. parkeri, R. bellii, R. rhipicephali, R. amblyommii and R. felis. Sixteen samples (4.4% reacted to at least one Rickettsia species. Among positive animals, two dogs (15.5% showed suggestive titers for R. bellii exposure. One sample had a homologous reaction to R. felis, a confirmed human pathogen. Although Rickettsia spp. circulation in dogs in the area studied may be considered at low prevalence, suggesting low risk of human infection, the present data demonstrate for the first time the exposure of dogs to R. bellii and R. felis in Southern Brazil.A febre maculosa brasileira (FMB é uma zoonose veiculada por carrapatos e causada pela bactéria Rickettsia rickettsii, podendo os cães ser hospedeiros sentinelas para essa bactéria. O objetivo do estudo foi determinar a presença de anticorpos contra Rickettsia spp. em cães de São José dos Pinhais, estado do Paraná, Sul do Brasil. Entre fevereiro de 2006 e julho de 2007, amostras séricas de 364 cães foram coletadas e testadas na diluição de 1:64 por Reação de Imunofluorescência Indireta (RIFI contra R. rickettsii e R. parkeri. Todos os soros reagentes para pelo menos uma espécie de Rickettsia foram testados contra as seis principais espécies de Rickettsia identificadas no Brasil: R

  4. Bacterial small RNAs in the Genus Rickettsia

    OpenAIRE

    Schroeder, Casey L. C.; Narra, Hema P.; Rojas, Mark; Sahni, Abha; Patel, Jignesh; Khanipov, Kamil; Wood, Thomas G.; Fofanov, Yuriy; Sahni, Sanjeev K.

    2015-01-01

    Background Rickettsia species are obligate intracellular Gram-negative pathogenic bacteria and the etiologic agents of diseases such as Rocky Mountain spotted fever (RMSF), Mediterranean spotted fever, epidemic typhus, and murine typhus. Genome sequencing revealed that R. prowazekii has ~25 % non-coding DNA, the majority of which is thought to be either “junk DNA” or pseudogenes resulting from genomic reduction. These characteristics also define other Rickettsia genomes. Bacterial small RNAs,...

  5. Riesgo de recurrencia ganglionar y valoración evolutiva en pacientes con carcinoma de mama en estadios precoces y sometidas a la biopsia selectiva del ganglio centinela

    OpenAIRE

    Domènech Vilardell, Anna

    2011-01-01

    ANTECEDENTES DEL TEMA: El estado ganglionar axilar es el factor pronóstico más importante para determinar la supervivencia y la recurrencia en el carcinoma de mama, puesto que es conocido que la afectación axilar en estas pacientes, disminuye la supervivencia a los 5 años del 85-95 % al 55-70 % y conlleva a que presenten metástasis a distancia con más frecuencia . De todos modos, la introducción y amplia utilización del cribado mamográfico está aumentando la detección de tumores incipientes ...

  6. 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 an

  7. 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... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3500 Rickettsia serological reagents. (a) Identification. Rickettsia serological reagents are devices that consist of...

  8. Molecular detection of Rickettsia conorii and other zoonotic spotted fever group rickettsiae in ticks, Romania.

    Science.gov (United States)

    Ionita, Mariana; Silaghi, Cornelia; Mitrea, Ioan Liviu; Edouard, Sophie; Parola, Philippe; Pfister, Kurt

    2016-02-01

    The diverse tick fauna as well as the abundance of tick populations in Romania represent potential risks for both human and animal health. Spotted fever group (SFG) rickettsiae are recognized as important agents of emerging human tick-borne diseases worldwide. However, the epidemiology of rickettsial diseases has been poorly investigated in Romania. In urban habitats, companion animals which are frequently exposed to tick infestation, play a role in maintenance of tick populations and as reservoirs of tick-borne pathogens. Therefore, the aim of the present study was to investigate the occurrence of SFG rickettsiae in ticks infesting dogs in a greater urban area in South-eastern Romania. Adult ixodid ticks (n=205), including Rhipicephalus sanguineus sensu lato (n=120), Dermacentor reticulatus (n=76) and Ixodes ricinus (n=9) were collected from naturally infested dogs and were screened for SFG rickettsiae using conventional PCR followed by sequencing. Additionally, ticks were screened for DNA of Babesia spp., Hepatozoon spp., Ehrlichia canis, and Anaplasma platys. Four zoonotic SFG rickettsiae were identified: Rickettsia raoultii (16%) and Rickettsia slovaca (3%) in D. reticulatus, Rickettsia monacensis (11%) in I. ricinus, and Rickettsia conorii (0.8%) in Rh. sanguineus s.l. Moreover, pathogens of veterinary importance, such as B. canis (21%) in D. reticulatus and E. canis (7.5%) in Rh. sanguineus s.l. were identified. The findings expand the knowledge on distribution of SFG rickettsiae as well as canine pathogens in Romania. Additionally, this is the first report describing the molecular detection of R. conorii in ticks from Romania.

  9. Molecular detection of Rickettsia africae, Rickettsia aeschlimannii, and Rickettsia sibirica mongolitimonae in camels and Hyalomma spp. ticks from Israel.

    Science.gov (United States)

    Kleinerman, Gabriela; Baneth, Gad; Mumcuoglu, Kosta Y; van Straten, Michael; Berlin, Dalia; Apanaskevich, Dmitry A; Abdeen, Ziad; Nasereddin, Abed; Harrus, Shimon

    2013-12-01

    In this study, we aimed to identify and genetically characterize spotted fever group (SFG) rickettsiae in ticks, domestic one-humped camels, and horses from farms and Bedouin communities in southern Israel. A total of 618 ixodid ticks (Hyalomma dromedarii, Hyalomma turanicum, Hyalomma excavatum, and Hyalomma impeltatum) collected from camels and horses, as well as 152 blood samples from 148 camels and four horses were included in the study. Initial screening for rickettsiae was carried out by targeting the gltA gene. Positive samples were further analyzed for rickettsial ompA, 17kDa, ompB, and 16S rRNA genes. Rickettsia aeschlimannii DNA was detected in the blood of three camels and 14 ticks (H. dromedarii, H. turanicum, and H. excavatum). Rickettsia africae was found in six ticks (H. turanicum, H. impeltatum, H. dromedarii, and H. excavatum). In addition, Rickettsia sibirica mongolitimonae was detected in one H. turanicum tick. These findings represent the first autochthonous detection of R. africae in Israel. Previous detections of R. africae in Asia were reported from the Sinai Peninsula (Egypt) and Istanbul, only. Furthermore, we report for the first time the finding of R. aeschlimannii in H. turanicum and H. excavatum ticks, as well as the first identification of R. sibirica mongolitimonae in H. turanicum ticks. The tick species identified to harbor R. africae and other SFG rickettsiae have been reported to occasionally feed on people, and, therefore, physicians should be aware of the possible exposure of local communities and travelers, especially those in contact with camels, to these tick-borne rickettsial pathogens.

  10. [A simple method for counting Rickettsia cells].

    Science.gov (United States)

    Emel'ianov, V V

    1990-01-01

    A simple modification of the method for counting Rickettsiae is described. The Escherichia coli cells (ECC) which served as reference particles were stained in suspension with methylene blue mixed with Rickettsia prowazekii (RP) and quickly sprayed over the glass slide. After fixation the samples were stained according to the technique of Gimenez and examined in the light microscope under oil immersion. Through a grid in the eye-piece it was not so difficult to count red-coloured RP and dark-blue ECC against a background formed by impurities. To calculate RP concentration, the reference particles' concentration was multiplied by the dilution factor of RP suspension by the ratio of RP to ECC enumerated. The statistical approach has shown that the wash of the slides during staining procedure does not change this ratio. Differential staining of Rickettsiae with fuchsin is the main clue of this new method to count them even in the crude preparations of infected yolk sacs. PMID:1693751

  11. 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

    Directory of Open Access Journals (Sweden)

    Rojo Vázquez Jaime

    1997-01-01

    Full Text Available 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 1/128 y > a 1/64 o superiores, respectivamente y 104 sueros humanos y 84 caninos frente a R. conorii (positividad a título > a 1/64 o superiores en ambas especies mediante inmunofluorescencia indirecta (IFI. RESULTADOS: Se halló positividad a las dos infecciones, tanto en personas como en perros. Frente a B. burgdorferi fue superior en humanos que en perros y frente a R. conorii fue superior en éstos que en humanos. En personas fue del 4,08% frente a B. burgdorferi y 1% frente a R. conorii; en perros fue del 2,10% frente a B. burgdorferi y del 14,28% frente a R. conorii. Los valores más altos se hallaron en los meses de primavera-verano, salvo en el caso de B. burgdorferi en perros. La seroprevalencia fue mayor en perros dedicados al cuidado de ganado (ovino que en los de caza y guarda. CONCLUSIONES: Los porcentajes de seroprevalencia hallados en nuestro trabajo, tanto en seres humanos como en caninos, considerados en el ámbito territorial de una zona geográfica semi-rural de la provincia de León, han sido iguales o inferiores a los reseñados para otras provincias, incluida la totalidad de la de León. En perros se halló mayor seroprevalencia frente a R. conorii que frente a B. burgdorferi, lo que indica que es el agente más extendido en nuestra Provincia, como han señalado otros autores. Los valores hallados en seres humanos frente a B. burgdorferi han sido más altos que en perros; la existencia de reacciones cruzadas con otros

  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. First report on the occurrence of Rickettsia slovaca and Rickettsia raoultii in Dermacentor silvarum in China

    Directory of Open Access Journals (Sweden)

    Tian Zhan-Cheng

    2012-01-01

    Full Text Available Abstract Background Rickettsioses are among both the longest known and most recently recognized infectious diseases. Although new spotted fever group rickettsiae have been isolated in many parts of the world including China, Little is known about the epidemiology of Rickettsia pathogens in ticks from Xinjiang Autonomous Region of China. Methods In an attempt to assess the potential risk of rickettsial infection after exposure to ticks in Xinjiang Uygur Autonomous Region of China, a total of 200 Dermacentor silvarum ticks collected in Xinyuan district were screened by polymerase chain reaction based on the outer membrane protein A gene. Results 22 of the 200 specimens (11% were found to be positive by PCR. Phylogenetic analysis of OmpA sequences identified two rickettsial species, Rickettsia raoultii (4.5% and Rickettsia slovaca (6.5%. Conclusions This study has reported the occurrence of Rickettsia raoultii and Rickettsia slovaca in Xinjiang Autonomous Region of China and suggests that Dermacentor silvarum could be involved in the transmission of rickettsial agents in China. Further studies on the characterization and culture of rickettsial species found in Dermacentor silvarum should be performed to further clarify this. Additionally, the screening of human specimens for rickettsial disease in this region will define the incidence of infection.

  14. Rickettsia felis in Xenopsylla cheopis, Java, Indonesia

    OpenAIRE

    Jiang, Ju; Soeatmadji, Djoko W.; Henry, Katherine M; Ratiwayanto, Sutanti; Michael J. Bangs; Richards, Allen L.

    2006-01-01

    Rickettsia typhi and R. felis, etiologic agents of murine typhus and fleaborne spotted fever, respectively, were detected in Oriental rat fleas (Xenopsylla cheopis) collected from rodents and shrews in Java, Indonesia. We describe the first evidence of R. felis in Indonesia and naturally occurring R. felis in Oriental rat fleas.

  15. Rickettsia slovaca infection in humans, Portugal.

    Science.gov (United States)

    de Sousa, Rita; Pereira, Branca Isabel; Nazareth, Claúdia; Cabral, Susana; Ventura, Conceição; Crespo, Pedro; Marques, Nuno; da Cunha, Saraiva

    2013-10-01

    Fifteen years after the initial detection of Rickettsia slovaca in ticks in Portugal, 3 autochthonous cases of R. slovaca infection were diagnosed in humans. All patients had an eschar on the scalp and lymphadenopathy; 2 patients had facial edema. R. slovaca infection was confirmed by serologic testing, culture, and PCR.

  16. Human infections with Rickettsia raoultii, China.

    Science.gov (United States)

    Jia, Na; Zheng, Yuan-Chun; Ma, Lan; Huo, Qiu-Bo; Ni, Xue-Bing; Jiang, Bao-Gui; Chu, Yan-Li; Jiang, Rui-Ruo; Jiang, Jia-Fu; Cao, Wu-Chun

    2014-05-01

    We used molecular methods to identify Rickettsia raoultii infections in 2 persons in China. These persons had localized rashes around sites of tick bites. R. raoultii DNA was detected in 4% of Dermacentor silvarum ticks collected in the same area of China and in 1 feeding tick detached from 1 patient.

  17. Detection of Rickettsia and Anaplasma from hard ticks in Thailand.

    Science.gov (United States)

    Malaisri, Premnika; Hirunkanokpun, Supanee; Baimai, Visut; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2015-12-01

    We collected a total of 169 adult hard ticks and 120 nymphs from under the leaves of plants located along tourist nature trails in ten localities. The results present data examining the vector competence of ticks of different genera and the presence of Rickettsia and Anaplasma species. The ticks belonged to three genera, Amblyomma, Dermacentor, and Haemaphysalis, comprising 11 species. Rickettsia bacteria were detected at three collection sites, while Anaplasma bacteria were detected at only one site. Phylogenetic analysis revealed new rickettsia genotypes from Thailand that were closely related to Rickettsia tamurae, Rickettsia monacensis, and Rickettsia montana. This study was also the first to show that Anaplasma bacteria are found in Haemaphysalis shimoga ticks and are closely related evolutionarily to Anaplasma bovis. These results provide additional information for the geographical distribution of tick species and tick-borne bacteria in Thailand and can therefore be applied for ecotourism management. PMID:26611960

  18. Detection of Rickettsia and Anaplasma from hard ticks in Thailand.

    Science.gov (United States)

    Malaisri, Premnika; Hirunkanokpun, Supanee; Baimai, Visut; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2015-12-01

    We collected a total of 169 adult hard ticks and 120 nymphs from under the leaves of plants located along tourist nature trails in ten localities. The results present data examining the vector competence of ticks of different genera and the presence of Rickettsia and Anaplasma species. The ticks belonged to three genera, Amblyomma, Dermacentor, and Haemaphysalis, comprising 11 species. Rickettsia bacteria were detected at three collection sites, while Anaplasma bacteria were detected at only one site. Phylogenetic analysis revealed new rickettsia genotypes from Thailand that were closely related to Rickettsia tamurae, Rickettsia monacensis, and Rickettsia montana. This study was also the first to show that Anaplasma bacteria are found in Haemaphysalis shimoga ticks and are closely related evolutionarily to Anaplasma bovis. These results provide additional information for the geographical distribution of tick species and tick-borne bacteria in Thailand and can therefore be applied for ecotourism management.

  19. 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

  20. Rickettsia influences thermotolerance in the whitefly Bemisia tabaci B biotype

    Institute of Scientific and Technical Information of China (English)

    Marina Brumin; Svetlana Kontsedalov; Murad Ghanim

    2011-01-01

    The whitefly Bemisia tabaci harbors Portiera aleyrodidarum,an obligatory symbiotic bacterium,as well as several secondary symbionts,including Rickettsia,Hamiltonella,Wolbachia,Arsenophonus,Cardinium and Fritschea,the function of which is unknown.In Israel,Rickettsia is found in both the B and Q of B.tabaci biotypes,and while all other secondary symbionts are located in the bacteriomes,Rickettsia can occupy most of the body cavity of the insect.We tested whether Rickettsia influences the biology of B.tabaci and found that exposing a Rickettsia-containing population to increasing temperatures significantly increases its tolerance to heat shock that reached 40℃,compared to a Rickettsia-free population.This increase in tolerance to heat shock was not associated with specific induction of heat-shock protein gene expression; however,it was associated with eduction in Rickettsia numbers as was assessed by quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analyses.To assess the causes for thermotolerance when ickettsia is reduced,we tested whether its presence is associated with the induction of genes required for thermotolerance.We found that under normal 25℃ rearing temperature,genes associated with response to stress such as cytoskeleton genes are induced in the Rickettsia-containing population.Thus,the presence of Rickettsia in B.tabaci under normal conditions induces the expression of genes required for thermotolerance that under high temperatures indirectly lead to this tolerance.

  1. Plasmids and rickettsial evolution: insight from Rickettsia felis.

    Directory of Open Access Journals (Sweden)

    Joseph J Gillespie

    Full Text Available BACKGROUND: The genome sequence of Rickettsia felis revealed a number of rickettsial genetic anomalies that likely contribute not only to a large genome size relative to other rickettsiae, but also to phenotypic oddities that have confounded the categorization of R. felis as either typhus group (TG or spotted fever group (SFG rickettsiae. Most intriguing was the first report from rickettsiae of a conjugative plasmid (pRF that contains 68 putative open reading frames, several of which are predicted to encode proteins with high similarity to conjugative machinery in other plasmid-containing bacteria. METHODOLOGY/PRINCIPAL FINDINGS: Using phylogeny estimation, we determined the mode of inheritance of pRF genes relative to conserved rickettsial chromosomal genes. Phylogenies of chromosomal genes were in agreement with other published rickettsial trees. However, phylogenies including pRF genes yielded different topologies and suggest a close relationship between pRF and ancestral group (AG rickettsiae, including the recently completed genome of R. bellii str. RML369-C. This relatedness is further supported by the distribution of pRF genes across other rickettsiae, as 10 pRF genes (or inactive derivatives also occur in AG (but not SFG rickettsiae, with five of these genes characteristic of typical plasmids. Detailed characterization of pRF genes resulted in two novel findings: the identification of oriV and replication termination regions, and the likelihood that a second proposed plasmid, pRFdelta, is an artifact of the original genome assembly. CONCLUSION/SIGNIFICANCE: Altogether, we propose a new rickettsial classification scheme with the addition of a fourth lineage, transitional group (TRG rickettsiae, that is unique from TG and SFG rickettsiae and harbors genes from possible exchanges with AG rickettsiae via conjugation. We offer insight into the evolution of a plastic plasmid system in rickettsiae, including the role plasmids may have played in

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

    Science.gov (United States)

    Sumrandee, Chalao; Hirunkanokpun, Supanee; Doornbos, Kathryn; Kitthawee, Sangvorn; Baimai, Visut; Grubhoffer, Libor; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2014-10-01

    Some reptile ticks are potential vectors of pathogens such as spotted fever group (SFG) rickettsiae. Here, we report for the first time in detail the molecular evidence, DNA sequences and phylogenetic studies, for the presence of Rickettsia spp. in Amblyomma ticks (Amblyomma helvolum and Amblyomma varanense) from snakes in Thailand. A total of 24 tick samples was collected from 4 snake species and identified. A phylogenetic analysis inferred from the partial sequences of the gltA gene indicated that the Rickettsia spp. from 2 Amblyomma helvolum and 1 Amblyomma varanense belong to the same group as the SFG rickettsiae, which are closely related to Rickettsia raoultii strains. In contrast, there was 1 Rickettsia sp. from Amblyomma helvolum grouped into the same clade with other SFG rickettsiae (Rickettsia tamurae, Rickettsia monacensis, and a Rickettsia endosymbiont of Amblyomma dubitatum from Brazil). However, another Rickettsia sp. from Amblyomma varanense was closely related to Rickettsia bellii and Rickettsia sp. strain RDa420 from Thailand. In addition, from phylogenetic results based on the 16S rRNA gene and a concatenated tree of the 3 genes (gltA, ompA, and ompB), we found what may be a novel SFG rickettsia species closely related to Rickettsia raoultii (from both Amblyomma varanense and Amblyomma helvolum). In conclusion, our findings are the first report on the presence of novel SFG rickettsiae in 2 snake tick species, Amblyomma varanense and Amblyomma helvolum in Thailand and in south-eastern Asia.

  3. Detecting Rickettsia parkeri infection from eschar swab specimens.

    Science.gov (United States)

    Myers, Todd; Lalani, Tahaniyat; Dent, Mike; Jiang, Ju; Daly, Patrick L; Maguire, Jason D; Richards, Allen L

    2013-05-01

    The typical clinical presentation of several spotted fever group Rickettsia infections includes eschars. Clinical diagnosis of the condition is usually made by analysis of blood samples. We describe a more sensitive, noninvasive means of obtaining a sample for diagnosis by using an eschar swab specimen from patients infected with Rickettsia parkeri.

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

    Directory of Open Access Journals (Sweden)

    Reimerink Johan HJ

    2010-06-01

    Full Text Available Abstract 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 and presenting these findings as new or potentially pathogenic Rickettsiae should be done with caution: a recent report suggested presence of a known human pathogen, R. australis, in questing I. ricinus ticks in Europe. A refined analysis of these results revealed that R. helvetica was most likely to be misinterpreted as R. australis. Evidence in the literature is accumulating that rickettsial DNA sequences found in tick lysates can also be derived from other sources than viable, pathogenic Rickettsiae. For example, from endosymbionts, environmental contamination or even horizontal gene transfer.

  5. Molecular detection of Rickettsia bellii and Rickettsia sp. strain Colombianensi in ticks from Cordoba, Colombia.

    Science.gov (United States)

    Miranda, Jorge; Mattar, Salim

    2014-03-01

    The purpose of this study was to provide molecular evidence of Rickettsia spp. in ticks collected from 2 sites of Cordoba. From May to June 2009, 1069 Amblyomma cajennense ticks were removed from 40 capybaras (Hydrochoerus hydrochaeris) in a rural locality of Monteria. Furthermore, 458 Amblyomma sp. larvae and 20 Amblyomma sp. nymphs were collected in a rural locality of Los Cordobas (Cordoba) by drag sampling on vegetation (n=1547). Ticks were grouped into pools and tested for rickettsial infection by real-time PCR targeting the rickettsial gene gltA. Subsequently, PCR targeting for gltA, ompA, ompB, and 16S rRNA, sequencing, and phylogenetic analyses were undertaken. Rickettsial DNA was detected in 10 (4.6%) out of 214 pools of ticks by RT-PCR. Five (33%) of free-living Amblyomma sp. larval pools were positive, as well as 5 (2.6%) pools from A. cajennense. Only the gltA gene was amplified from 5 pools of free-living larvae. The nucleotide sequences were 100% identical to R. bellii by BLAST. Only one pool from A. cajennense was positive for gltA, ompA, ompB, and 16S rRNA. The partial nucleotide sequences of these genes were 100% identical to nucleotide sequences of the same genes of a new proposed species Candidatus Rickettsia sp. strain Colombianensi. This is the first report of R. bellii in ticks in Colombia and the second report of detection of Candidatus Rickettsia sp. strain Colombianensi. These Rickettsia species are still considered of unknown pathogenicity. Further studies are needed to characterize the ecological and potential pathogenic role of these 2 Rickettsia species found in Cordoba.

  6. Identificación molecular y análisis de la relación filogenética de especies de Rickettsias presentes en garrapatas provenientes de tres regiones de Colombia

    OpenAIRE

    Ramírez Hernández, Alejandro

    2014-01-01

    Las Rickettsiosis son enfermedades emergentes zoonóticas asociadas a artrópodos. Éstas son producidas por la infección de bacterias del género Rickettsia (Da Rocha-Lima, 1916) las cuales son alfa-proteobacterias que se caracterizan por ser parásitos intracelulares obligados y porque pueden desencadenar enfermedad febril inespecífica en humanos y animales, las cuales, si no son diagnosticadas y tratadas de forma oportuna pueden tener un desenlace fatal. En su ciclo biológico, las rickettsias d...

  7. Coexistência de linfadenite axilar tuberculosa e metástase ganglionar de carcinoma lobular de mama: relato de um caso Coexistence of axillary tuberculous lymphadenitis and ganglionic metastasis in mammary lobular carcinoma: a case report

    Directory of Open Access Journals (Sweden)

    José Juvenal Linhares

    2005-07-01

    Full Text Available Relato do caso de uma mulher com 83 anos apresentando nódulo e retração de pele na mama direita com oito meses de evolução. Ao exame físico verificou-se nódulo sólido de 5 cm, localizado no quadrante súpero-lateral de mama direita, associado a presença de retração de pele correspondente e linfonodos axilares não coalescentes ipsilaterais. O resultado da mamografia evidenciou nódulo de 4 cm de diâmetro irregular no quadrante súpero-lateral da mama direita (bi-rads V. Estádio clínico: T2N1M0 (IIB. O tratamento cirúrgico incluiu mastectomia radical modificada (à Maden com dissecção axilar níveis I, II e III. Avaliação histopatológica demonstrou a presença de carcinoma lobular infiltrativo que mediu 2,5 cm (T2, presença de linfadenite granulomatosa causada por tuberculose em linfonodos dos níveis I, II e III, associados a metástase de carcinoma lobular em um único nível linfático, nível I. Estádio patológico: pT2pN1aM0. A paciente recebeu tratamento para tuberculose ganglionar com rifampicina, isoniazida e pirazinamida por um ano. Foram solicitados receptores hormonais, os quais mostraram-se positivos, sendo feito terapia adjuvante com tamoxifeno. Durante o primeiro ano de seguimento a paciente evoluiu bem, sem sinais de recidiva local ou metástases a distância.Report of a case of an 83-year-old woman presenting a nodule and skin retraction in the right breast for eight months. On physical examination, a solid nodule of 5 cm was observed, located in the upper-lateral quadrant of the right breast, associated with skin retraction and ipsilateral lymph nodes. Mammographic findings showed irregularly limited nodules of 4 cm in the upper-lateral quadrant of the right breast (bi-rads V. Clinical staging: T2N1M0 (IIB. Surgical treatment included a modified radical mastectomy with axillary dissection levels I, II, and III. Histopathologic evaluation demonstrated the presence of an infiltrating lobular carcinoma

  8. 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; Bouattour, Ali

    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.

  9. Dynamics of the endosymbiont Rickettsia in an insect pest.

    Science.gov (United States)

    Cass, Bodil N; Yallouz, Rachel; Bondy, Elizabeth C; Mozes-Daube, Netta; Horowitz, A Rami; Kelly, Suzanne E; Zchori-Fein, Einat; Hunter, Martha S

    2015-07-01

    A new heritable bacterial association can bring a fresh set of molecular capabilities, providing an insect host with an almost instantaneous genome extension. Increasingly acknowledged as agents of rapid evolution, inherited microbes remain underappreciated players in pest management programs. A Rickettsia bacterium was tracked sweeping through populations of an invasive whitefly provisionally described as the "B" or "MEAM1" of the Bemisia tabaci species complex, in the southwestern USA. In this population, Rickettsia provides strong fitness benefits and distorts whitefly sex ratios under laboratory conditions. In contrast, whiteflies in Israel show few apparent fitness benefits from Rickettsia under laboratory conditions, only slightly decreasing development time. A survey of B. tabaci B samples revealed the distribution of Rickettsia across the cotton-growing regions of Israel and the USA. Thirteen sites from Israel and 22 sites from the USA were sampled. Across the USA, Rickettsia frequencies were heterogeneous among regions, but were generally very high, whereas in Israel, the infection rates were lower and declining. The distinct outcomes of Rickettsia infection in these two countries conform to previously reported phenotypic differences. Intermediate frequencies in some areas in both countries may indicate a cost to infection in certain environments or that the frequencies are in flux. This suggests underlying geographic differences in the interactions between bacterial symbionts and this serious agricultural pest. PMID:25626393

  10. Rickettsia species in fleas collected from small mammals in Slovakia.

    Science.gov (United States)

    Špitalská, Eva; Boldiš, Vojtech; Mošanský, Ladislav; Sparagano, Olivier; Stanko, Michal

    2015-11-01

    Epidemiological and epizootiological studies of Rickettsia felis and other Rickettsia spp. are very important, because their natural cycle has not yet been established completely. In total, 315 fleas (Siphonaptera) of 11 species of Ceratophyllidae, Hystrichopsyllidae and Leptopsyllidae families were tested for the presence of Rickettsia species and Coxiella burnetii with conventional and specific quantitative real-time PCR assays. Fleas were collected from five rodent hosts (Myodes glareolus, Apodemus flavicollis, Apodemus agrarius, Microtus subterraneus, Microtus arvalis) and three shrew species (Sorex araneus, Neomys fodiens, Crocidura suaveolens) captured in Eastern and Southern Slovakia. Overall, Rickettsia spp. was found in 10.8% (34/315) of the tested fleas of Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus uncinatus and Nosopsyllus fasciatus species. Infected fleas were coming from A. flavicollis, A. agrarius, and M. glareolus captured in Eastern Slovakia. C. burnetii was not found in any fleas. R. felis, Rickettsia helvetica, unidentified Rickettsia, and rickettsial endosymbionts were identified in fleas infesting small mammals in the Košice region, Eastern Slovakia. This study is the first report of R. felis infection in C. solutus male flea collected from A. agrarius in Slovakia.

  11. Dynamics of the endosymbiont Rickettsia in an insect pest.

    Science.gov (United States)

    Cass, Bodil N; Yallouz, Rachel; Bondy, Elizabeth C; Mozes-Daube, Netta; Horowitz, A Rami; Kelly, Suzanne E; Zchori-Fein, Einat; Hunter, Martha S

    2015-07-01

    A new heritable bacterial association can bring a fresh set of molecular capabilities, providing an insect host with an almost instantaneous genome extension. Increasingly acknowledged as agents of rapid evolution, inherited microbes remain underappreciated players in pest management programs. A Rickettsia bacterium was tracked sweeping through populations of an invasive whitefly provisionally described as the "B" or "MEAM1" of the Bemisia tabaci species complex, in the southwestern USA. In this population, Rickettsia provides strong fitness benefits and distorts whitefly sex ratios under laboratory conditions. In contrast, whiteflies in Israel show few apparent fitness benefits from Rickettsia under laboratory conditions, only slightly decreasing development time. A survey of B. tabaci B samples revealed the distribution of Rickettsia across the cotton-growing regions of Israel and the USA. Thirteen sites from Israel and 22 sites from the USA were sampled. Across the USA, Rickettsia frequencies were heterogeneous among regions, but were generally very high, whereas in Israel, the infection rates were lower and declining. The distinct outcomes of Rickettsia infection in these two countries conform to previously reported phenotypic differences. Intermediate frequencies in some areas in both countries may indicate a cost to infection in certain environments or that the frequencies are in flux. This suggests underlying geographic differences in the interactions between bacterial symbionts and this serious agricultural pest.

  12. Genetic variability of Rickettsia spp. in Ixodes persulcatus/Ixodes trianguliceps sympatric areas from Western Siberia, Russia: Identification of a new Candidatus Rickettsia species.

    Science.gov (United States)

    Igolkina, Yana P; Rar, Vera A; Yakimenko, Valeriy V; Malkova, Marina G; Tancev, Aleksey K; Tikunov, Artem Yu; Epikhina, Tamara I; Tikunova, Nina V

    2015-08-01

    Rickettsia spp. are the causative agents of a number of diseases in humans. These bacteria are transmitted by arthropods, including ixodid ticks. DNA of several Rickettsia spp. was identified in Ixodes persulcatus ticks, however, the association of Ixodes trianguliceps ticks with Rickettsia spp. is unknown. In our study, blood samples of small mammals (n=108), unfed adult I. persulcatus ticks (n=136), and I. persulcatus (n=12) and I. trianguliceps (n=34) ticks feeding on voles were collected in two I. persulcatus/I. trianguliceps sympatric areas in Western Siberia. Using nested PCR, ticks and blood samples were studied for the presence of Rickettsia spp. Three distinct Rickettsia species were found in ticks, but no Rickettsia species were found in the blood of examined voles. Candidatus Rickettsia tarasevichiae DNA was detected in 89.7% of unfed I. persulcatus, 91.7% of engorged I. persulcatus and 14.7% of I. trianguliceps ticks. Rickettsia helvetica DNA was detected in 5.9% of I. trianguliceps ticks. In addition, a new Rickettsia genetic variant was found in 32.4% of I. trianguliceps ticks. Sequence analysis of the 16S rRNA, gltA, ompA, оmpB and sca4 genes was performed and, in accordance with genetic criteria, a new Rickettsia genetic variant was classified as a new Candidatus Rickettsia species. We propose to name this species Candidatus Rickettsia uralica, according to the territory where this species was initially identified. Candidatus Rickettsia uralica was found to belong to the spotted fever group. The data obtained in this study leads us to propose that Candidatus Rickettsia uralica is associated with I. trianguliceps ticks.

  13. 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.

  14. Progress in the insect symbiont Rickettsia%昆虫共生细菌 Rickettsia 的研究进展

    Institute of Scientific and Technical Information of China (English)

    潘慧鹏; 张友军

    2012-01-01

    Rickettsia是传播和引起人类与其他脊椎动物疾病的胞内共生菌.引起脊椎动物疾病的这些Rickettsia,其部分生活史是在节肢动物体内完成的;而另外许多Rickettsia,其整个生活史都是在宿主节肢动物体内完成.为了叙述方便,把前者称为脊椎动物Rickettsia,后者称为节肢动物Rickettsia.过去的研究主要集中在医学上具有重大意义的脊椎动物Rickettsia,而关于节肢动物Rickettsia的生物学特性等研究则相对较少.近年来,研究者们加大了对昆虫Rickettsia的研究,发现昆虫Rickettsia广泛分布于昆虫中,且有两种存在形式.其可以通过垂直卵传的方式在世代间传递,也可以通过寄生蜂和寄主植物达到在昆虫之间传播的目的.昆虫Rickettsia可通过诱导孤雌生殖、诱导杀雄等方式影响宿主的生殖行为.其对不同宿主昆虫可产生对宿主有利或有害的作用;可增强宿主昆虫抵御高温和寄生蜂的能力,与宿主昆虫对药剂的敏感性相关.最后,昆虫Rickettsia具有一个简化的基因组,且存在进一步减小的可能性.%Rickettsia species are intracellular symbionts of eukaryotes that are well known for infecting and causing serious diseases in humans and other vertebrates. All known vertebrate associated Rickettsia bacteria are vectored by arthropods as part of their life-cycle, and many other Rickettsia species are found exclusively in arthropods without any secondary host. For convenience, we refer to the former as vertebrate Rickettsia and the latter as arthropod Rickettsia. Previous research efforts mainly focused on medically important vertebrate Rickettsia. The biological studies of arthropod Rickettsia were limited- In recent years, more efforts have been made on the insect symbiont Rickettsia and considerable achievements have been obtained. The insect symbiont Rickettsia is distributed among insects, and two different localization patterns exist in the same insect

  15. Rickettsia felis Infection in a Common Household Insect Pest, Liposcelis bostrychophila (Psocoptera: Liposcelidae)▿ †

    OpenAIRE

    Behar, Adi; McCormick, Laurie J.; Perlman, Steve J.

    2010-01-01

    Many species of Rickettsia are well-known mammalian pathogens transmitted by blood-feeding arthropods. However, molecular surveys are continually uncovering novel Rickettsia species, often in unexpected hosts, including many arthropods that do not feed on blood. This study reports a systematic molecular characterization of a Rickettsia infecting the psocid Liposcelis bostrychophila (Psocoptera: Liposcelidae), a common and cosmopolitan household pest. Surprisingly, the psocid Rickettsia is sho...

  16. A novel Rickettsia species detected in Vole Ticks (Ixodes angustus) from Western Canada.

    Science.gov (United States)

    Anstead, Clare A; Chilton, Neil B

    2013-12-01

    The genomic DNA of ixodid ticks from western Canada was tested by PCR for the presence of Rickettsia. No rickettsiae were detected in Ixodes sculptus, whereas 18% of the I. angustus and 42% of the Dermacentor andersoni organisms examined were PCR positive for Rickettsia. The rickettsiae from each tick species were characterized genetically using multiple genes. Rickettsiae within the D. andersoni organisms had sequences at four genes that matched those of R. peacockii. In contrast, the Rickettsia present within the larvae, nymphs, and adults of I. angustus had novel DNA sequences at four of the genes characterized compared to the sequences available from GenBank for all recognized species of Rickettsia and all other putative species within the genus. Phylogenetic analyses of the sequence data revealed that the rickettsiae in I. angustus do not belong to the spotted fever, transitional, or typhus groups of rickettsiae but are most closely related to "Candidatus Rickettsia kingi" and belong to a clade that also includes R. canadensis, "Candidatus Rickettsia tarasevichiae," and "Candidatus Rickettsia monteiroi."

  17. Rickettsia massiliae and Rickettsia conorii Israeli Spotted Fever Strain Differentially Regulate Endothelial Cell Responses.

    Science.gov (United States)

    Bechelli, Jeremy; Smalley, Claire; Milhano, Natacha; Walker, David H; Fang, Rong

    2015-01-01

    Rickettsiae primarily target microvascular endothelial cells. However, it remains elusive how endothelial cell responses to rickettsiae play a role in the pathogenesis of rickettsial diseases. In the present study, we employed two rickettsial species with high sequence homology but differing virulence to investigate the pathological endothelial cell responses. Rickettsia massiliae is a newly documented human pathogen that causes a mild spotted fever rickettsiosis. The "Israeli spotted fever" strain of R. conorii (ISF) causes severe disease with a mortality rate up to 30% in hospitalized patients. At 48 hours post infection (HPI), R. conorii (ISF) induced a significant elevation of IL-8 and IL-6 while R. massiliae induced a statistically significant elevated amount of MCP-1 at both transcriptional and protein synthesis levels. Strikingly, R. conorii (ISF), but not R. massiliae, caused a significant level of cell death or injury in HMEC-1 cells at 72 HPI, demonstrated by live-dead cell staining, annexin V staining and lactate dehydrogenase release. Monolayers of endothelial cells infected with R. conorii (ISF) showed a statistically significant decrease in electrical resistance across the monolayer compared to both R. massiliae-infected and uninfected cells at 72 HPI, suggesting increased endothelial permeability. Interestingly, pharmacological inhibitors of caspase-1 significantly reduced the release of lactate dehydrogenase by R. conorii (ISF)-infected HMEC-1 cells, which suggests the role of caspase-1 in mediating the death of endothelial cells. Taken together, our data illustrated that a distinct proinflammatory cytokine profile and endothelial dysfunction, as evidenced by endothelial cell death/injury and increased permeability, are associated with the severity of rickettsial diseases.

  18. Widespread Rickettsia spp. Infections in Ticks (Acari: Ixodoidea) in Taiwan.

    Science.gov (United States)

    Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Lee, Pei-Lung; Wu, Yin-Wen; Chung, Chien-Kung; Wang, Hsi-Chieh

    2015-09-01

    Ticks are second to mosquitoes as the most important disease vectors, and recent decades have witnessed the emergence of many novel tick-borne rickettsial diseases, but systematic surveys of ticks and tick-borne rickettsioses are generally lacking in Asia. We collected and identified ticks from small mammal hosts between 2006 and 2010 in different parts of Taiwan. Rickettsia spp. infections in ticks were identified by targeting ompB and gltA genes with nested polymerase chain reaction. In total, 2,732 ticks were collected from 1,356 small mammals. Rhipicephalus haemaphysaloides Supino (51.8% of total ticks), Haemaphysalis bandicota Hoogstraal & Kohls (28.0%), and Ixodes granulatus Supino (20.0%) were the most common tick species, and Rattus losea Swinhoe (44.7% of total ticks) and Bandicota indica Bechstein (39.9%) were the primary hosts. The average Rickettsia infective rate in 329 assayed ticks was 31.9% and eight Rickettsia spp. or closely related species were identified. This study shows that rickettsiae-infected ticks are widespread in Taiwan, with a high diversity of Rickettsia spp. circulating in the ticks. Because notifiable rickettsial diseases in Taiwan only include mite-borne scrub typhus and flea-borne murine typhus, more studies are warranted for a better understanding of the real extent of human risks to rickettsioses in Taiwan. PMID:26336223

  19. Widespread Rickettsia spp. Infections in Ticks (Acari: Ixodoidea) in Taiwan.

    Science.gov (United States)

    Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Lee, Pei-Lung; Wu, Yin-Wen; Chung, Chien-Kung; Wang, Hsi-Chieh

    2015-09-01

    Ticks are second to mosquitoes as the most important disease vectors, and recent decades have witnessed the emergence of many novel tick-borne rickettsial diseases, but systematic surveys of ticks and tick-borne rickettsioses are generally lacking in Asia. We collected and identified ticks from small mammal hosts between 2006 and 2010 in different parts of Taiwan. Rickettsia spp. infections in ticks were identified by targeting ompB and gltA genes with nested polymerase chain reaction. In total, 2,732 ticks were collected from 1,356 small mammals. Rhipicephalus haemaphysaloides Supino (51.8% of total ticks), Haemaphysalis bandicota Hoogstraal & Kohls (28.0%), and Ixodes granulatus Supino (20.0%) were the most common tick species, and Rattus losea Swinhoe (44.7% of total ticks) and Bandicota indica Bechstein (39.9%) were the primary hosts. The average Rickettsia infective rate in 329 assayed ticks was 31.9% and eight Rickettsia spp. or closely related species were identified. This study shows that rickettsiae-infected ticks are widespread in Taiwan, with a high diversity of Rickettsia spp. circulating in the ticks. Because notifiable rickettsial diseases in Taiwan only include mite-borne scrub typhus and flea-borne murine typhus, more studies are warranted for a better understanding of the real extent of human risks to rickettsioses in Taiwan.

  20. Detección de Rickettsia spp. en Suero y Garrapatas de Mamíferos Silvestres en Cautiverio en Montería, Córdoba -resumen-

    OpenAIRE

    Dave Wehdeking-Hernández; Laura Hernández-Fernández; César Rojano-Bolaño; J Ruíz-Rodríguez

    2014-01-01

    Las rickettsiosis transmitidas por garrapatas son causadas por bacterias intracelulares pertenecientes al grupo de las fiebres manchadas del género Rickettsia. Estas zoonosis son algunas de las enfermedades transmitidas por vectores de más antiguo conocimiento‚ e incluyen dentro de su ciclo de transmisión diversas especies de mamíferos. No obstante‚ en Colombia existen pocos trabajos enfocados a conocer la dinámica de las rickettsiosis en animales silvestres. El objetivo de este estudio fue d...

  1. Genotyping, evolution and epidemiological findings of Rickettsia species.

    Science.gov (United States)

    Merhej, Vicky; Angelakis, Emmanouil; Socolovschi, Cristina; Raoult, Didier

    2014-07-01

    Rickettsiae are obligate intracellular bacteria that can cause mild to life-threatening diseases, including epidemic typhus, one of the oldest pernicious diseases of mankind. Clinical awareness of rickettsial diseases and molecular diagnosis have shown that rickettsioses should be viewed as new emerging and reemerging diseases. Rickettsia has been shown to be a large genus with a worldwide distribution, a very diverse host range, including hosts that have no relationship with vertebrate. Genomic studies have demonstrated genome reduction due to gene loss associated with increased pathogenicity and horizontal DNA acquisition according to a sympatric mode of evolution in hosts that contain several organisms. This article presents a review of genotyping techniques and examines the principle of genotype determination in terms of taxonomic strategies and detection methods. This article summarizes the epidemiological and pathological features of Rickettsia and discusses the genomic findings that help the understanding of the evolution of pathogenicity including the deleterious mutations of repair systems and the toxin-antitoxin systems.

  2. Rickettsia conorii israelensis in Rhipicephalus sanguineus ticks, Sardinia, Italy.

    Science.gov (United States)

    Chisu, Valentina; Masala, Giovanna; Foxi, Cipriano; Socolovschi, Cristina; Raoult, Didier; Parola, Philippe

    2014-06-01

    The presence of tick-borne Rickettsia spp. was examined by PCR using DNA samples extracted from 254 ticks collected from mammals originating from northern and eastern Sardinia, Italy. The spotted fever group rickettsial agent Rickettsia conorii israelensis was detected in 3 Rhipicephalus sanguineus ticks from a dog for the first time in this geographical area. In addition, Ri. massiliae, Ri. slovaca, and Ri. aeschlimannii were detected in Rh. turanicus, Rh. sanguineus, Dermacentor marginatus, and Hyalomma marginatum marginatum ticks from dogs, goats, wild boar, and horse. Moreover, Candidatus Rickettsia barbariae was detected in 2 Rh. turanicus ticks from goats. The detection of Ri. conorii israelensis, an emergent agent which causes Israeli spotted fever, increases our knowledge on tick-borne rickettsioses in Sardinia.

  3. Rickettsia felis as Emergent Global Threat for Humans

    Science.gov (United States)

    Pérez-Osorio, Carlos E.; Zavala-Velázquez, Jorge E.; León, Juan José Arias

    2008-01-01

    Rickettsia felis is an emergent pathogen belonging to transitional group rickettsiae. First described in 1990, R. felis infections have been reported to occur worldwide in fleas, mammals, and humans. Because clinical signs of the illness are similar to those of murine typhus and other febrile illnesses such as dengue, the infection in humans is likely underestimated. R. felis has been found throughout the world in several types of ectoparasites; cat fleas appear to be the most common vectors. R. felis infection should be considered an emergent threat to human health. PMID:18598619

  4. A Case of Human Infection by Rickettsia slovaca in Greece.

    Science.gov (United States)

    Kostopoulou, Vasiliki; Chochlakis, Dimosthenis; Kanta, Chrysoula; Katsanou, Andromachi; Rossiou, Konstantina; Rammos, Aidonis; Papadopoulos, Spyridon-Filippos; Katsarou, Theodora; Tselentis, Yannis; Psaroulaki, Anna; Boukas, Chrysostomos

    2016-07-22

    Although tick-borne rickettsiosis is endemic in Greece, until recently, human samples arriving at the National Reference Centre under suspicion of rickettsial infection were routinely tested only for Rickettsia typhi and R. conorii. However, identification of additional rickettsia species in ticks prompted revision of the protocol in 2010. Until that year, all human samples received by the laboratory were tested for antibodies against R. conorii and R. typhi only. Now, tests for R. slovaca, R. felis, and R. mongolotimonae are all included in routine analysis. The current description of a human R. slovaca case is possible as a result of these changes in routine testing. PMID:26370429

  5. 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.

  6. Coinfection with "Rickettsia sibirica subsp. mongolotimonae" and Rickettsia conorii in a Human Patient: a Challenge for Molecular Diagnosis Tools.

    Science.gov (United States)

    Nogueras, María Mercedes; Roson, Beatriz; Lario, Sergio; Sanfeliu, Isabel; Pons, Immaculada; Anton, Esperança; Casanovas, Aurora; Segura, Ferran

    2015-09-01

    Rickettsioses are zoonoses transmitted by vectors. More than one agent can coexist in vectors. Although vectors may transmit more than one microorganism to humans, information on dual infections is scarce. We present a case of a patient with an atypical rickettsiosis diagnosis in whom two species of Rickettsia were detected.

  7. Rickettsia lusitaniae sp. nov. isolated from the soft tick Ornithodoros erraticus (Acarina: Argasidae).

    Science.gov (United States)

    Milhano, Natacha; Palma, Mariana; Marcili, Arlei; Núncio, Maria Sofia; de Carvalho, Isabel Lopes; de Sousa, Rita

    2014-05-01

    In this study a novel Rickettsia from the spotted fever group, isolated from Ornithodoros erraticus soft ticks collected from pigpens in the south of Portugal, is described. After initial screening revealed Rickettsia-positive ticks, isolation attempts were then performed. Successful isolates were achieved by shell-vial technique using Vero E6 cells at 28°C. Molecular characterization of the isolate was performed based on analysis of five rickettsial genes gltA, ompA, ompB, sca1 and htr with their subsequent concatenation along with other rickettsial species resulting in a clustering of the new isolate with Rickettsia felis and Rickettsia hoogstraalii. The degree of nucleotide sequence similarity with other rickettsiae fulfills the criteria for classification of our isolate as a novel species. The name Rickettsia lusitaniae sp. nov. (=CEVDI PoTiRo) is proposed for this new species found in O. erraticus.

  8. 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.

  9. Ixodes pacificus ticks maintain embryogenesis and egg hatching after antibiotic treatment of Rickettsia endosymbiont.

    Science.gov (United States)

    Kurlovs, Andre H; Li, Jinze; Cheng, Du; Zhong, Jianmin

    2014-01-01

    Rickettsia is a genus of intracellular bacteria that causes a variety of diseases in humans and other mammals and associates with a diverse group of arthropods. Although Rickettsia appears to be common in ticks, most Rickettsia-tick relationships remain generally uncharacterized. The most intimate of these associations is Rickettsia species phylotype G021, a maternally and transstadially transmitted endosymbiont that resides in 100% of I. pacificus in California. We investigated the effects of this Rickettsia phylotype on I. pacificus reproductive fitness using selective antibiotic treatment. Ciprofloxacin was 10-fold more effective than tetracycline in eliminating Rickettsia from I. pacificus, and quantitative PCR results showed that eggs from the ciprofloxacin-treated ticks contained an average of 0.02 Rickettsia per egg cell as opposed to the average of 0.2 in the tetracycline-treated ticks. Ampicillin did not significantly affect the number of Rickettsia per tick cell in adults or eggs compared to the water-injected control ticks. We found no relationship between tick embryogenesis and rickettsial density in engorged I. pacificus females. Tetracycline treatment significantly delayed oviposition of I. pacificus ticks, but the antibiotic's effect was unlikely related to Rickettsia. We also demonstrated that Rickettsia-free eggs could successfully develop into larvae without any significant decrease in hatching compared to eggs containing Rickettsia. No significant differences in the incubation period, egg hatching rate, and the number of larvae were found between any of the antibiotic-treated groups and the water-injected tick control. We concluded that Rickettsia species phylotype G021 does not have an apparent effect on embryogenesis, oviposition, and egg hatching of I. pacificus.

  10. Rickettsia infection in Amblyomma tonelliae, a tick species from the Amblyomma cajennense complex.

    Science.gov (United States)

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

    2015-03-01

    The present study was performed to evaluate the Rickettsia infection in Amblyomma tonelliae ticks from Argentina. All ticks were subjected to DNA extraction and tested by a battery of PCRs to amplify fragments of four rickettsial genes, 23S-5S, gltA, ompA and htrA. Two ticks were positive. The Rickettsia detected in one tick represents a new lineage which is named Rickettsia sp. strain El Tunal. This new strain belongs to the canadensis group because it is closely related to Rickettsia monteiroi, Rickettsia canadensis and Candidatus "Rickettsia tarasevichiae". They clustered together on a high supported clade with both gltA and htrA genes. The other positive tick was infected with Candidatus "Rickettsia amblyommii". The results presented in this study constitute the first records of Rickettsia infection in A. tonelliae ticks. However, the medical relevance of these findings should be considered cautiously because the pathogenicity of Rickettsia sp. strain El Tunal and Candidatus "R. amblyommii" remains undetermined.

  11. Molecular detection of the human pathogenic Rickettsia sp. strain Atlantic rainforest in Amblyomma dubitatum ticks from Argentina.

    Science.gov (United States)

    Monje, Lucas D; Nava, Santiago; Eberhardt, Ayelen T; Correa, Ana I; Guglielmone, Alberto A; Beldomenico, Pablo M

    2015-02-01

    To date, three tick-borne pathogenic Rickettsia species have been reported in different regions of Argentina, namely, R. rickettsii, R. parkeri, and R. massiliae. However, there are no reports available for the presence of tick-borne pathogens from the northeastern region of Argentina. This study evaluated the infection with Rickettsia species of Amblyomma dubitatum ticks collected from vegetation and feeding from capybaras (Hydrochoerus hydrochaeris) in northeastern Argentina. From a total of 374 A. dubitatum ticks collected and evaluated by PCR for the presence of rickettsial DNA, 19 were positive for the presence of Rickettsia bellii DNA, two were positive for Rickettsia sp. strain COOPERI, and one was positive for the pathogenic Rickettsia sp. strain Atlantic rainforest. To our knowledge, this study is the first report of the presence of the human pathogen Rickettsia sp. strain Atlantic rainforest and Rickettsia sp. strain COOPERI in Argentina. Moreover, our findings posit A. dubitatum as a potential vector for this pathogenic strain of Rickettsia.

  12. 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.

  13. An infection of Ruditapes decussatus (Bivalvia) by Rickettsia

    OpenAIRE

    Mialhe, Eric; Chagot, Dominique; Boulo, Viviane; Comps, Michel; Ruano, Francisco; Grizel, Henri

    1987-01-01

    The authors report the presence of a Rickettsia in Ruditapes decussatus from natural populations of the Algarve (Portugal). Light microscopic shows infections of varying importance in gill tissues. Some enclose small procaryotic colonies (cp) scattered in all lamellae; in others, the colonies are scarce and hypertrophic (100 mu m). These different pictures suggest an amplification process. Digestive diverticulae may also be infected, but to a lesser extent. The ultrastructural features of thi...

  14. Experimental Infection of Amblyomma aureolatum Ticks with Rickettsia rickettsii

    OpenAIRE

    Labruna, Marcelo B.; Ogrzewalska, Maria; Soares, João F.; Martins, Thiago F.; Soares, Herbert S.; Moraes-Filho, Jonas; Nieri-Bastos, Fernanda A.; Almeida, Aliny P.; Pinter, Adriano

    2011-01-01

    We experimentally infected Amblyomma aureolatum ticks with the bacterium Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever (RMSF). These ticks are a vector for RMSF in Brazil. R. rickettsii was efficiently conserved by both transstadial maintenance and vertical (transovarial) transmission to 100% of the ticks through 4 laboratory generations. However, lower reproductive performance and survival of infected females was attributed to R. rickettsii infection. Therefore, ...

  15. Rickettsia felis infection in cat fleas Ctenocephalides felis felis

    Directory of Open Access Journals (Sweden)

    Mauricio C. Horta

    2010-10-01

    Full Text Available The present study evaluated the rickettsial infection in a laboratory colony of cat fleas, Ctenocephalides felis felis (Bouche in Brazil. All flea samples (30 eggs, 30 larvae, 30 cocoons, 30 males, and 30 females tested by polymerase chain reaction (PCR were shown to contain rickettsial DNA. PCR products, corresponding to the rickettsial gltA, htrA, ompA and ompB gene partial sequences were sequenced and showed to correspond to Rickettsia felis, indicating that the flea colony was 100% infected by R. felis. The immunofluorescence assay (IFA showed the presence of R. felis-reactive antibodies in blood sera of 7 (87.5% out of 8 cats that were regularly used to feed the flea colony. From 15 humans that used to work with the flea colony in the laboratory, 6 (40.0% reacted positively to R. felis by IFA. Reactive feline and human sera showed low endpoint titers against R. felis, varying from 64 to 256. With the exception of one human serum, all R. felis-reactive sera were also reactive to Rickettsia rickettsii and/or Rickettsia parkeri antigens at similar titers to R. felis. The single human serum that was reactive solely to R. felis had an endpoint titer of 256, indicating that this person was infected by R. felis.

  16. 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.

  17. Spotted fever group rickettsia closely related to Rickettsia monacensis isolated from ticks in South Jeolla province, Korea.

    Science.gov (United States)

    Lee, Kyung-Min; Choi, Yeon-Joo; Shin, Sun-Hye; Choi, Min-Kyung; Song, Hyeon-Je; Kim, Heung-Chul; Klein, Terry A; Richards, Allen L; Park, Kyung-Hee; Jang, Won-Jong

    2013-07-01

    Rickettsia monacensis, a spotted fever group rickettsia, was isolated from Ixodes nipponensis ticks collected from live-captured small mammals in South Jeolla province, Korea in 2006. Homogenates of tick tissues were inoculated into L929 and Vero cell monolayers using shell vial assays. After several passages, Giemsa staining revealed rickettsia-like organisms in the inoculated Vero cells, but not the L929 cells. Sequencing analysis revealed that the ompA-small part (25-614 bp region), ompA-large part (2849-4455 bp region), nearly full-length ompB (58-4889 bp region) and gltA (196-1236 bp region) of the isolates had similarities of 100%, 99.8%, 99.3% and 99.5%, respectively, to those of R. monacensis. Furthermore, phylogenetic analysis showed that the isolate was grouped into the cluster in the same way as R. monacensis in the trees of all genes examined. These results strongly suggest that the isolate is closely related to R. monacensis. As far as is known, this is the first report of isolation of R. monacensis from ticks in Korea.

  18. Rickettsia spp. in Seabird Ticks from Western Indian Ocean Islands, 2011–2012

    OpenAIRE

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

    2014-01-01

    We found a diversity of Rickettsia spp. in seabird ticks from 6 tropical islands. The bacteria showed strong host specificity and sequence similarity with strains in other regions. Seabird ticks may be key reservoirs for pathogenic Rickettsia spp., and bird hosts may have a role in dispersing ticks and tick-associated infectious agents over large distances.

  19. Rickettsia spp. in seabird ticks from western Indian Ocean islands, 2011-2012.

    Science.gov (United States)

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

    2014-05-01

    We found a diversity of Rickettsia spp. in seabird ticks from 6 tropical islands. The bacteria showed strong host specificity and sequence similarity with strains in other regions. Seabird ticks may be key reservoirs for pathogenic Rickettsia spp., and bird hosts may have a role in dispersing ticks and tick-associated infectious agents over large distances.

  20. High prevalence of Rickettsia spp. infections in small mammals in Taiwan.

    Science.gov (United States)

    Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Wang, Hsi-Chieh

    2015-01-01

    Surveillance for Rickettsia spp. is urgently needed due to the recent emergence of many novel rickettsioses around the globe, but previous studies in Taiwan have been limited to small areas and no investigation of infections in vertebrate hosts has ever been attempted. We surveyed rickettsial infections systematically in small-mammal hosts trapped between 2006 and 2010 throughout Taiwan. Fragments of ompB and gltA genes in the liver, spleen, and kidney of mammals were targeted by nested polymerase chain reaction. We trapped 1375 individuals of 10 species, among which Rattus losea was the most common (54.6%), followed by Suncus murinus (20.6%) and Mus caroli (10.6%). The overall rate of Rickettsia infections in the liver, spleen, or kidney of 309 assayed small mammals was 60.5%, with a rate of infection ≥50% for each mammal species. DNA nucleotide sequences of 184 successfully sequenced genes were most similar to nine Rickettsia species: Rickettsia conorii, R. felis, R. japonica, R. raoultii, R. rickettsii, Rickettsia sp. IG-1, Rickettsia sp. TwKM01, Rickettsia sp. TwKM02, and R. typhi. Our results suggest that several novel Rickettsia spp. are common and widespread across various habitats throughout Taiwan and suggest the need for further study of emerging rickettsioses in Taiwan.

  1. Rickettsia felis Infection in a Common Household Insect Pest, Liposcelis bostrychophila (Psocoptera: Liposcelidae)▿ †

    Science.gov (United States)

    Behar, Adi; McCormick, Laurie J.; Perlman, Steve J.

    2010-01-01

    Many species of Rickettsia are well-known mammalian pathogens transmitted by blood-feeding arthropods. However, molecular surveys are continually uncovering novel Rickettsia species, often in unexpected hosts, including many arthropods that do not feed on blood. This study reports a systematic molecular characterization of a Rickettsia infecting the psocid Liposcelis bostrychophila (Psocoptera: Liposcelidae), a common and cosmopolitan household pest. Surprisingly, the psocid Rickettsia is shown to be Rickettsia felis, a human pathogen transmitted by fleas that causes serious morbidity and occasional mortality. The plasmid from the psocid R. felis was sequenced and was found to be virtually identical to the one in R. felis from fleas. As Liposcelis insects are often intimately associated with humans and other vertebrates, it is speculated that they acquired R. felis from fleas. Whether the R. felis in psocids causes disease in vertebrates is not known and warrants further study. PMID:20139311

  2. Rickettsia prowazekii transports UMP and GMP, but not CMP, as building blocks for RNA synthesis.

    Science.gov (United States)

    Winkler, H H; Daugherty, R; Hu, F

    1999-05-01

    Rickettsia prowazekii, the etiological agent of epidemic typhus, is an obligate intracellular bacterium and is apparently unable to synthesize ribonucleotides de novo. Here, we show that as an alternative, isolated, purified R. prowazekii organisms transported exogenous uridyl- and guanylribonucleotides and incorporated these labeled precursors into their RNA in a rifampin-sensitive manner. Transport systems for nucleotides, which we have shown previously and show here are present in rickettsiae, have never been reported in free-living bacteria, and the usual nucleobase and nucleoside transport systems are absent in rickettsiae. There was a clear preference for the monophosphate form of ribonucleotides as the transported substrate. In contrast, rickettsiae did not transport cytidylribonucleotides. The source of rickettsial CTP appears to be the transport of UMP followed by its phosphorylation and the amination of intrarickettsial UTP to CTP by CTP synthetase. A complete schema of nucleotide metabolism in rickettsiae is presented that is based on a combination of biochemical, physiological, and genetic information. PMID:10322027

  3. Detección de Rickettsia spp. en Suero y Garrapatas de Mamíferos Silvestres en Cautiverio en Montería, Córdoba -resumen-

    Directory of Open Access Journals (Sweden)

    Dave Wehdeking-Hernández

    2014-12-01

    Full Text Available Las rickettsiosis transmitidas por garrapatas son causadas por bacterias intracelulares pertenecientes al grupo de las fiebres manchadas del género Rickettsia. Estas zoonosis son algunas de las enfermedades transmitidas por vectores de más antiguo conocimiento‚ e incluyen dentro de su ciclo de transmisión diversas especies de mamíferos. No obstante‚ en Colombia existen pocos trabajos enfocados a conocer la dinámica de las rickettsiosis en animales silvestres. El objetivo de este estudio fue detectar‚ por medio de la técnica de PCR en tiempo real‚ la presencia de Rickettsia spp.‚ en muestras de suero y garrapatas colectadas en mamíferos mantenidos en cautiverio en el Centro de Atención y Valoración de Fauna Silvestre de la Corporación autónoma Regional de los Valles del Sinú y San Jorge CAV-CVS‚ entre los años 2009 y 2014. Se obtuvieron muestras de sangre de 14 felinos‚ de las especies Leopardus pardalis (10‚ Puma concolor (3 y Panthera onca (1; de 58 primates‚ correspondientes a las especies Ateles geofroyii (17‚ Alouatta seniculus (14‚ Cebus capucinus (14‚ Saguinus oedipus (6‚ Cebus albifrons (4 Aotus sp. (2 y Ateles belzebuth (1; y de otros mamíferos: Tayassu pecari (1‚ Procyon cancrivorous (1 y Cerdocyon thous (1. En cuanto a las garrapatas‚ se colectaron e identificaron individuos del género Haemaphysalis sp. en un ejemplar de Sylvilagus sp.‚ y de las especies Amblyomma ovale‚ Riphicephalus microplus y Dermacentor nitens en P. concolor. Posteriormente fueron organizadas en pool. No se encontraron muestras de suero positivas a Rickettsia spp. (0/72. Se detectó un pool de garrapatas de la especie A. ovale positivo a este microorganismo. Este es el primer reporte en Colombia de ectoparásitos de Puma concolor positivos a Rickettsia spp. Se requiere continuar con los muestreos de ectoparásitos para determinar si este microorganismo se encuentra circulante entre mamíferos silvestres en el país.

  4. 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

  5. Rickettsia felis, an emerging flea-transmitted human pathogen

    OpenAIRE

    Abdad, Mohammad Yazid; Stenos, John; Graves, Stephen

    2011-01-01

    Rickettsia felis was first recognised two decades ago and has now been described as endemic to all continents except Antarctica. The rickettsiosis caused by R. felis is known as flea-borne spotted fever or cat-flea typhus. The large number of arthropod species found to harbour R. felis, and be potential vectors, supports the view that it is a pan-global microbe. The main arthropod reservoir and vector is the cat flea, Ctenocephalides felis, yet a further twenty other species of fleas, ticks a...

  6. Rickettsia felis infection in cat fleas Ctenocephalides felis felis

    OpenAIRE

    Horta, Mauricio C.; Fabio B. Scott; Thaís R. Correia; Julio I. Fernandes; Leonardo J. Richtzenhain; Labruna, Marcelo B.

    2010-01-01

    The present study evaluated the rickettsial infection in a laboratory colony of cat fleas, Ctenocephalides felis felis (Bouche) in Brazil. All flea samples (30 eggs, 30 larvae, 30 cocoons, 30 males, and 30 females) tested by polymerase chain reaction (PCR) were shown to contain rickettsial DNA. PCR products, corresponding to the rickettsial gltA, htrA, ompA and ompB gene partial sequences were sequenced and showed to correspond to Rickettsia felis, indicating that the flea colony was 100% inf...

  7. [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.

  8. Characterization of the symbiont Rickettsia in the mirid bug Nesidiocoris tenuis (Reuter) (Heteroptera: Miridae).

    Science.gov (United States)

    Caspi-Fluger, A; Inbar, M; Steinberg, S; Friedmann, Y; Freund, M; Mozes-Daube, N; Zchori-Fein, E

    2014-12-01

    Nesidiocoris tenuis (Reuter) (Heteroptera: Miridae) is an omnivorous insect used for biological control. Augmentative release and conservation of N. tenuis have been used for pest control in tomato crops. Intracellular bacterial symbionts of arthropods are common in nature and have diverse effects on their hosts; in some cases they can dramatically affect biological control. Fingerprinting methods showed that the symbiotic complex associated with N. tenuis includes Wolbachia and Rickettsia. Rickettsia of N. tenuis was further characterized by sequencing the 16S rRNA and gltA bacterial genes, measuring its amount in different developmental stages of the insect by real-time polymerase chain reaction, and localizing the bacteria in the insect's body by fluorescence in situ hybridization. The Rickettsia in N. tenuis exhibited 99 and 96% similarity of both sequenced genes to Rickettsia bellii and Rickettsia reported from Bemisia tabaci, respectively. The highest amount of Rickettsia was measured in the 5th instar and adult, and the symbionts could be detected in the host gut and ovaries. Although the role played by Rickettsia in the biology of N. tenuis is currently unknown, their high amount in the adults and localization in the gut suggest that they may have a nutritional role in this insect.

  9. Molecular Detection of Rickettsia Species Within Ticks (Acari: Ixodidae) Collected from Arkansas United States.

    Science.gov (United States)

    Trout Fryxell, R T; Steelman, C D; Szalanski, A L; Billingsley, P M; Williamson, P C

    2015-05-01

    Rocky Mountain spotted fever (RMSF), caused by the etiological agent Rickettsia rickettsii, is the most severe and frequently reported rickettsial illness in the United States, and is commonly diagnosed throughout the southeast. With the discoveries of Rickettsia parkeri and other spotted fever group rickettsiae (SFGR) in ticks, it remains inconclusive if the cases reported as RMSF are truly caused by R. rickettsii or other SFGR. Arkansas reports one of the highest incidence rates of RMSF in the country; consequently, to identify the rickettsiae in Arkansas, 1,731 ticks, 250 white-tailed deer, and 189 canines were screened by polymerase chain reaction (PCR) for the rickettsial genes gltA, rompB, and ompA. None of the white-tailed deer were positive, while two of the canines (1.1%) and 502 (29.0%) of the ticks were PCR positive. Five different tick species were PCR positive: 244 (37%) Amblyomma americanum L., 130 (38%) Ixodes scapularis Say, 65 (39%) Amblyomma maculatum (Koch), 30 (9%) Rhipicephalus sanguineus Latreille, 7 (4%) Dermacentor variabilis Say, and 26 (44%) unidentified Amblyomma ticks. None of the sequenced products were homologous to R. rickettsii. The most common Rickettsia via rompB amplification was Rickettsia montanensis and nonpathogenic Candidatus Rickettsia amblyommii, whereas with ompA amplification the most common Rickettsia was Ca. R. amblyommii. Many tick specimens collected in northwest Arkansas were PCR positive and these were commonly A. americanum harboring Ca. R. amblyommii, a currently nonpathogenic Rickettsia. Data reported here indicate that pathogenic R. rickettsii was absent from these ticks and suggest by extension that other SFGR are likely the causative agents for Arkansas diagnosed RMSF cases.

  10. Molecular detection and groEL typing of Rickettsia aeschlimannii in Sardinian ticks.

    Science.gov (United States)

    Chisu, Valentina; Zobba, Rosanna; Foxi, Cipriano; Pisu, Danilo; Masala, Giovanna; Alberti, Alberto

    2016-09-01

    Rickettsia aeschlimannii is an emerging tick-borne pathogen of the spotted fever group Rickettsiae with considerable impact on both human and animal health. This study reports the molecular detection and groEL characterization of R. aeschlimannii in ticks collected from birds and ruminants in a typical Mediterranean environment. Phylogeny of R. aeschlimannii and species representative of the spotted fever and typhus groups based on the groEL gene is reconstructed for the first time. Results expand the knowledge on distribution and typing of emerging human tick-borne diseases in Sardinia and pave the way for future molecular epidemiology studies of zoonotic Rickettsiae. PMID:27130322

  11. Rickettsia bellii in Amblyomma rotundatum ticks parasitizing Rhinella jimi from northeastern Brazil.

    Science.gov (United States)

    Horta, Mauricio C; Saraiva, Danilo G; Oliveira, Glauber M B; Martins, Thiago F; Labruna, Marcelo B

    2015-01-01

    This study evaluated rickettsial infection in Amblyomma rotundatum ticks collected from toads (Rhinella jimi) in the Brazilian Caatinga biome, an unique semiarid region of South America. Tick infestations were observed in 57.8% toads (26/45); mean infestation: 1.6 ticks/toad. DNA extraction from 42 ticks (6 larvae, 22 nymphs and 11 female adults) was tested by polymerase chain reaction (PCR) targeting Rickettsia organisms, which were detected in 100% of the ticks. Amplicons' DNA sequences were identical to each other and 99% identical to Rickettsia bellii from GenBank. DNA samples extracted from the blood of the 45 toads were negative by rickettsia-PCR protocols.

  12. Comparative growth of spotted fever group Rickettsia spp. strains in Vero cells

    Science.gov (United States)

    Silva, Arannadia Barbosa; Duarte, Myrian Morato; Vizzoni, Vinicius Figueiredo; Duré, Ana Íris de Lima; Lopéz, Diego Montenegro; Nogueira, Rita de Maria Seabra; Soares, Carlos Augusto Gomes; Machado-Ferreira, Erik; Gazêta, Gilberto Salles

    2016-01-01

    In Brazil, the spotted fever group (SFG) Rickettsia rickettsii and Rickettsia parkeri related species are the etiological agents of spotted fever rickettsiosis. However, the SFG, Rickettsia rhipicephali, that infects humans, has never been reported. The study of growth dynamics can be useful for understanding the infective and invasive capacity of these pathogens. Here, the growth rates of the Brazilian isolates R. rickettsii str. Taiaçu, R. parkeri str. At#24, and R. rhipicephali HJ#5, were evaluated in Vero cells by quantitative polymerase chain reaction. R. rhipicephali showed different kinetic growth compared to R. rickettsii and R. parkeri. PMID:27508322

  13. Detección de Rickettsia spp. en Garrapatas de Myrmecophaga tridactyla de Vida Libre en la Sabana Inundable de Casanare‚ Colombia -resumen-

    Directory of Open Access Journals (Sweden)

    César Rojano-Bolaño

    2014-12-01

    Full Text Available Las bacterias del género Rickettsia son organismos con distribución mundial‚ causantes de algunas enfermedades zoonóticas de gran importancia en salud pública. Sin embargo‚ en Colombia son pocos los estudios enfocados a conocer su distribución y los vectores involucrados. El objetivo de este estudio fue detectar la presencia de Rickettsia spp.‚ en garrapatas colectadas en nueve osos palmeros (Myrmecophaga tridactyla de vida libre en el municipio de Pore‚ Casanare‚ entre los años 2013 y 2014. Los osos palmeros fueron capturados con el método de búsqueda activa‚ para posteriormente ser anestesiados utilizando un dardo con una combinación anestésica consistente en Ketamina 12 mg/kg y Xilacina 0‚5 mg/kg por vía intramuscular. Las garrapatas fueron colectadas directamente de los individuos‚ con ayuda de pinzas. En total se obtuvieron 204 ectoparásitos‚ que fueron almacenados en alcohol al 70%‚ y posteriormente fueron identificados como pertenecientes a la especie Amblyomma cajennense. Las garrapatas se organizaron en 68 pool de tres individuos y fueron analizadas por medio de la técnica de PCR en tiempo real. Se detectaron 12 pool de garrapatas positivos a este microorganismo (17‚6%. Los resultados preliminares de este estudio muestran que Rickettsia spp.‚ bacteria intracelular importante en salud pública‚ se encuentra circulante entre ectoparásitos de animales silvestres en la sabana inundable del municipio de Pore‚ Casanare. Dado que diversos estudios han reportado que los rickettsiales tienen una mayor incidencia en ambientes húmedos‚ se recomienda continuar con los estudios en mamíferos silvestres y sus garrapatas en la sabana natural inundable.

  14. Isolation of Candidatus Rickettsia asemboensis from Ctenocephalides Fleas.

    Science.gov (United States)

    Luce-Fedrow, Alison; Maina, Alice N; Otiang, Elkanah; Ade, Fredrick; Omulo, Sylvia; Ogola, Eric; Ochieng, Linus; Njenga, M Kariuki; Richards, Allen L

    2015-04-01

    Candidatus Rickettsia asemboensis was identified molecularly in fleas collected in 2009 from Asembo, Kenya. Multilocus sequence typing using the 17-kD antigen gene, rrs, gltA, ompA, ompB, and sca4 demonstrated that Candidatus R. asemboensis is closely related to Rickettsia felis but distinct enough to be considered for separate species classification. Following this molecular characterization of Candidatus R. asemboensis, the in vitro cultivation of this bacterium was then performed. We used Ctenocephalides canis and Ctenocephalides felis fleas removed from dogs in Kenya to initiate the in vitro isolation of Candidatus R. asemboensis. Successful cultures were obtained using Drosophila melanogaster S2 and Aedes albopictus C6/36 cell lines. Cytological staining and quantitative real-time PCR (qPCR) assays were used to visualize/confirm the culture of the bacteria in both cell lines. Sequencing of fragments of the 17-kD antigen gene, gltA, and ompB genes confirmed the identity of our Candidatus R. asemboensis isolates. To date, we have passaged Candidatus R. asemboensis 12 times through S2 and C6/36 cells, and active and frozen cultures are currently being maintained. This is the first time that a R. felis-like organism has been grown and maintained in culture and is therefore the first time that one of them, Candidatus R. asemboensis, has been characterized beyond molecular typing.

  15. 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. PMID:27273750

  16. Analysis of the Rickettsia africae genome reveals that virulence acquisition in Rickettsia species may be explained by genome reduction

    Directory of Open Access Journals (Sweden)

    Audic Stéphane

    2009-04-01

    Full Text Available Abstract Background The Rickettsia genus includes 25 validated species, 17 of which are proven human pathogens. Among these, the pathogenicity varies greatly, from the highly virulent R. prowazekii, which causes epidemic typhus and kills its arthropod host, to the mild pathogen R. africae, the agent of African tick-bite fever, which does not affect the fitness of its tick vector. Results We evaluated the clonality of R. africae in 70 patients and 155 ticks, and determined its genome sequence, which comprises a circular chromosome of 1,278,540 bp including a tra operon and an unstable 12,377-bp plasmid. To study the genetic characteristics associated with virulence, we compared this species to R. prowazekii, R. rickettsii and R. conorii. R. africae and R. prowazekii have, respectively, the less and most decayed genomes. Eighteen genes are present only in R. africae including one with a putative protease domain upregulated at 37°C. Conclusion Based on these data, we speculate that a loss of regulatory genes causes an increase of virulence of rickettsial species in ticks and mammals. We also speculate that in Rickettsia species virulence is mostly associated with gene loss. The genome sequence was deposited in GenBank under accession number [GenBank: NZ_AAUY01000001].

  17. 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

    2016-08-01

    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. PMID:27273647

  18. Spotted fever group rickettsiae in ticks collected from wild animals in Israel.

    Science.gov (United States)

    Keysary, Avi; Eremeeva, Marina E; Leitner, Moshe; Din, Adi Beth; Wikswo, Mary E; Mumcuoglu, Kosta Y; Inbar, Moshe; Wallach, Arian D; Shanas, Uri; King, Roni; Waner, Trevor

    2011-11-01

    We report molecular evidence for the presence of spotted fever group rickettsiae (SFGR) in ticks collected from roe deer, addax, red foxes, and wild boars in Israel. Rickettsia aeschlimannii was detected in Hyalomma marginatum and Hyalomma detritum while Rickettsia massiliae was present in Rhipicephalus turanicus ticks. Furthermore, a novel uncultured SFGR was detected in Haemaphysalis adleri and Haemaphysalis parva ticks from golden jackals. The pathogenicity of the novel SFGR for humans is unknown; however, the presence of multiple SFGR agents should be considered when serological surveillance data from Israel are interpreted because of significant antigenic cross-reactivity among Rickettsia. The epidemiology and ecology of SFGR in Israel appear to be more complicated than was previously believed. PMID:22049050

  19. Draft Genome Sequence of Rickettsia aeschlimannii, Associated with Hyalomma marginatum Ticks

    OpenAIRE

    Sentausa, Erwin; El Karkouri, Khalid; Michelle, Caroline; Raoult, Didier; Fournier, Pierre-Edouard

    2014-01-01

    Rickettsia aeschlimannii is a tick-associated human pathogen. We report here the draft genome of R. aeschlimannii strain MC16, isolated from Hyalomma marginatum marginatum ticks collected in Morocco.

  20. A prospective study evaluating the presence of Rickettsia in Danish patients with sarcoidosis

    DEFF Research Database (Denmark)

    Svendsen, Claus Bo; Milman, Nils; Nielsen, Henrik Winther;

    2009-01-01

    Rickettsia helvetica has previously been proposed as an aetiological agent in sarcoidosis. The purpose of the present study was to detect possible signs of Rickettsia infection in a Danish population of patients with sarcoidosis. Twenty-six patients with newly diagnosed sarcoidosis were...... interview. Evidence of rickettsial infection was assessed by an immunofluorescence assay testing for antibodies towards Rickettsia as well as specific real-time polymerase chain reaction (PCR) on lung biopsy specimens. We performed fluorescent in situ hybridization (FISH) on the biopsies to detect....... There was no difference in the reported frequency of tick bite between patients and controls. In conclusion, we found no evidence of Rickettsia being involved in the pathogenesis of sarcoidosis in Denmark....

  1. 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

    BACKGROUND: 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......, 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...

  2. Isolation of Rickettsia felis in the Mosquito Cell Line C6/36

    OpenAIRE

    Horta, Maurício C.; Labruna, Marcelo B.; Edison L. Durigon; Teresinha T.S. Schumaker

    2006-01-01

    We report the isolation and establishment of Rickettsia felis in the C6/36 cell line. Rickettsial growth was intense, always with 90 to 100% of cells being infected after few weeks. The rickettsial isolate was confirmed by testing infected cells by PCR and sequencing fragments of three major Rickettsia genes (gltA, ompB, and the 17-kDa protein gene).

  3. Infection of Amblyomma ovale by Rickettsia sp. strain Atlantic rainforest, Colombia.

    Science.gov (United States)

    Londoño, Andrés F; Díaz, Francisco J; Valbuena, Gustavo; Gazi, Michal; Labruna, Marcelo B; Hidalgo, Marylin; Mattar, Salim; Contreras, Verónica; Rodas, Juan D

    2014-10-01

    Our goal was to understand rickettsial spotted fevers' circulation in areas of previous outbreaks reported from 2006 to 2008 in Colombia. We herein present molecular identification and isolation of Rickettsia sp. Atlantic rainforest strain from Amblyomma ovale ticks, a strain shown to be pathogenic to humans. Infected ticks were found on dogs and a rodent in Antioquia and Córdoba Provinces. This is the first report of this rickettsia outside Brazil, which expands its known range considerably.

  4. A novel fluorescent in situ hybridization technique for detection of Rickettsia spp. in archival samples

    DEFF Research Database (Denmark)

    Svendsen, Claus Bo; Boye, Mette; Struve, Carsten;

    2009-01-01

    A novel, sensitive and specific method for detecting Rickettsia spp. in archival samples is described. The method involves the use of fluorescently marked oligonucleotide probes for in situ hybridization. Specific hybridization of Ricekttsia was found without problems of cross-reactions with bact......A novel, sensitive and specific method for detecting Rickettsia spp. in archival samples is described. The method involves the use of fluorescently marked oligonucleotide probes for in situ hybridization. Specific hybridization of Ricekttsia was found without problems of cross...

  5. Conditional fitness benefits of the Rickettsia bacterial symbiont in an insect pest.

    Science.gov (United States)

    Cass, Bodil N; Himler, Anna G; Bondy, Elizabeth C; Bergen, Jacquelyn E; Fung, Sierra K; Kelly, Suzanne E; Hunter, Martha S

    2016-01-01

    Inherited bacterial symbionts are common in arthropods and can have strong effects on the biology of their hosts. These effects are often mediated by host ecology. The Rickettsia symbiont can provide strong fitness benefits to its insect host, Bemisia tabaci, under laboratory and field conditions. However, the frequency of the symbiont is heterogeneous among field collection sites across the USA, suggesting that the benefits of the symbiont are contingent on additional factors. In two whitefly genetic lines collected from the same location, we tested the effect of Rickettsia on whitefly survival after heat shock, on whitefly competitiveness at different temperatures, and on whitefly competitiveness at different starting frequencies of Rickettsia. Rickettsia did not provide protection against heat shock nor affect the competitiveness of whiteflies at different temperatures or starting frequencies. However, there was a strong interaction between Rickettsia infection and whitefly genetic line. Performance measures indicated that Rickettsia was associated with significant female bias in both whitefly genetic lines, but in the second whitefly genetic line it conferred no significant fitness benefits nor conferred any competitive advantage to its host over uninfected whiteflies in population cages. These results help to explain other reports of variation in the phenotype of the symbiosis. Furthermore, they demonstrate the complex nature of these close symbiotic associations and the need to consider these interactions in the context of host population structure. PMID:26376661

  6. Detection and identification of Rickettsia species in Ixodes tick populations from Estonia.

    Science.gov (United States)

    Katargina, Olga; Geller, Julia; Ivanova, Anna; Värv, Kairi; Tefanova, Valentina; Vene, Sirkka; Lundkvist, Åke; Golovljova, Irina

    2015-09-01

    A total of 1640 ticks collected in different geographical parts of Estonia were screened for the presence of Rickettsia species DNA by real-time PCR. DNA of Rickettsia was detected in 83 out of 1640 questing ticks with an overall prevalence of 5.1%. The majority of the ticks infected by rickettsiae were Ixodes ricinus (74 of 83), while 9 of the 83 positive ticks were Ixodes persulcatus. For rickettsial species identification, a part of the citrate synthase gltA gene was sequenced. The majority of the positive samples were identified as Rickettsia helvetica (81 out of 83) and two of the samples were identified as Rickettsia monacensis and Candidatus R. tarasevichiae, respectively. Genetic characterization based on the partial gltA gene showed that the Estonian sequences within the R. helvetica, R. monacensis and Candidatus R. tarasevichiae species demonstrated 100% similarity with sequences deposited in GenBank, originating from Rickettsia species distributed over large territories from Europe to Asia.

  7. Conditional fitness benefits of the Rickettsia bacterial symbiont in an insect pest.

    Science.gov (United States)

    Cass, Bodil N; Himler, Anna G; Bondy, Elizabeth C; Bergen, Jacquelyn E; Fung, Sierra K; Kelly, Suzanne E; Hunter, Martha S

    2016-01-01

    Inherited bacterial symbionts are common in arthropods and can have strong effects on the biology of their hosts. These effects are often mediated by host ecology. The Rickettsia symbiont can provide strong fitness benefits to its insect host, Bemisia tabaci, under laboratory and field conditions. However, the frequency of the symbiont is heterogeneous among field collection sites across the USA, suggesting that the benefits of the symbiont are contingent on additional factors. In two whitefly genetic lines collected from the same location, we tested the effect of Rickettsia on whitefly survival after heat shock, on whitefly competitiveness at different temperatures, and on whitefly competitiveness at different starting frequencies of Rickettsia. Rickettsia did not provide protection against heat shock nor affect the competitiveness of whiteflies at different temperatures or starting frequencies. However, there was a strong interaction between Rickettsia infection and whitefly genetic line. Performance measures indicated that Rickettsia was associated with significant female bias in both whitefly genetic lines, but in the second whitefly genetic line it conferred no significant fitness benefits nor conferred any competitive advantage to its host over uninfected whiteflies in population cages. These results help to explain other reports of variation in the phenotype of the symbiosis. Furthermore, they demonstrate the complex nature of these close symbiotic associations and the need to consider these interactions in the context of host population structure.

  8. Rickettsia felis, an emerging flea-transmitted human pathogen

    Directory of Open Access Journals (Sweden)

    Stephen Graves

    2011-07-01

    Full Text Available Rickettsia felis was first recognised two decades ago and has now been described as endemic to all continents except Antarctica. The rickettsiosis caused by R. felis is known as flea-borne spotted fever or cat-flea typhus. The large number of arthropod species found to harbour R. felis and that may act as potential vectors support the view that it is a pan-global microbe. The main arthropod reservoir and vector is the cat flea, Ctenocephalides felis, yet more than 20 other species of fleas, ticks, and mites species have been reported to harbour R. felis. Few bacterial pathogens of humans have been found associated with such a diverse range of invertebrates. With the projected increase in global temperature over the next century, there is concern that changes to the ecology and distribution of R. felis vectors may adversely impact public health.

  9. Rickettsia retinitis cases in India: a few comments.

    Science.gov (United States)

    Tripathy, Koushik; Chawla, Rohan; Sharma, Yog Raj; Vohra, Rajpal

    2016-12-01

    An important cause of infectious retinitis, not well-described in Indian literature, has been analyzed in detail systematically by Kawali A. and colleagues. However, Rickettsia retinitis (RR) was diagnosed at titres of 1:160 by the Weil-Felix test (WFT). The sensitivity and specificity of WFT at this level are poor compared to the gold standard immunofluorescent antibody assay. However, we understand that financial constraints of the Indian patients limit the availability of more definite tests. In our opinion, the optical coherence tomography features of RR described by the authors may be mimicked by other causes of retinitis, such as toxoplasma retinitis or even cotton wool spots. Infectious retinitis including RR should be treated by an antimicrobial agent with or without oral steroids until larger series or randomized controlled trials prove otherwise. PMID:26920002

  10. Detection of antibodies anti-Rickettsia spp. in dogs and horses in the state of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius de Amorim

    2014-02-01

    Full Text Available This study evaluated the infection caused by Rickettsia spp. among dogs and horses from Mato Grosso State. A total of 384 dogs and 460 horses were tested by the Indirect Immunofluorescence Assay (IFA for Rickettsia rickettsii, Rickettsia parkeri, Rickettsia amblyommii, Rickettsia rhipicephali and Rickettsia bellii Overall, 3.12% (12/384 of the dogs were seroreactive for at least one Rickettsia species. A total of 7 (1.82% canine sera showed titers to R. bellii at least 4-fold higher than those to any of the other rickettsial antigens, allowing us to consider that these dogs were infected by R. bellii. In horses, 273 (59.34 % samples were positives for at least one antigen tested, and highest anti-Rickettsia spp. endpoint titers were observed for R. amblyommii, suggesting homologous reactions to this agent or a very closely related organism. The results showed that dogs are under low exposition to ticks infected with spotted fever group Rickettsia, indicating low risk of human infection by these agents. However, R. amblyommii is widely distributed in the State.

  11. Identification and Characterization of Novel Small RNAs in Rickettsia prowazekii

    Science.gov (United States)

    Schroeder, Casey L. C.; Narra, Hema P.; Sahni, Abha; Rojas, Mark; Khanipov, Kamil; Patel, Jignesh; Shah, Riya; Fofanov, Yuriy; Sahni, Sanjeev K.

    2016-01-01

    Emerging evidence implicates a critically important role for bacterial small RNAs (sRNAs) as post-transcriptional regulators of physiology, metabolism, stress/adaptive responses, and virulence, but the roles of sRNAs in pathogenic Rickettsia species remain poorly understood. Here, we report on the identification of both novel and well-known bacterial sRNAs in Rickettsia prowazekii, known to cause epidemic typhus in humans. RNA sequencing of human microvascular endothelial cells (HMECs), the preferred targets during human rickettsioses, infected with R. prowazekii revealed the presence of 35 trans-acting and 23 cis-acting sRNAs, respectively. Of these, expression of two trans-acting (Rp_sR17 and Rp_sR60) and one cis-acting (Rp_sR47) novel sRNAs and four well-characterized bacterial sRNAs (RNaseP_bact_a, α-tmRNA, 4.5S RNA, 6S RNA) was further confirmed by Northern blot or RT-PCR analyses. The transcriptional start sites of five novel rickettsial sRNAs and 6S RNA were next determined using 5′ RLM-RACE yielding evidence for their independent biogenesis in R. prowazekii. Finally, computational approaches were employed to determine the secondary structures and potential mRNA targets of novel sRNAs. Together, these results establish the presence and expression of sRNAs in R. prowazekii during host cell infection and suggest potential functional roles for these important post-transcriptional regulators in rickettsial biology and pathogenesis. PMID:27375581

  12. 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.

  13. High prevalence of "Candidatus Rickettsia andeanae" and apparent exclusion of Rickettsia parkeri in adult Amblyomma maculatum (Acari: Ixodidae) from Kansas and Oklahoma.

    Science.gov (United States)

    Paddock, Christopher D; Denison, Amy M; Dryden, Michael W; Noden, Bruce H; Lash, R Ryan; Abdelghani, Sarah S; Evans, Anna E; Kelly, Aubree R; Hecht, Joy A; Karpathy, Sandor E; Ganta, Roman R; Little, Susan E

    2015-04-01

    Amblyomma maculatum (the Gulf Coast tick), an aggressive, human-biting, Nearctic and Neotropical tick, is the principal vector of Rickettsia parkeri in the United States. This pathogenic spotted fever group Rickettsia species has been identified in 8-52% of questing adult Gulf Coast ticks in the southeastern United States. To our knowledge, R. parkeri has not been reported previously from adult specimens of A. maculatum collected in Kansas or Oklahoma. A total of 216 adult A. maculatum ticks were collected from 18 counties in Kansas and Oklahoma during 2011-2014 and evaluated by molecular methods for evidence of infection with R. parkeri. No infections with this agent were identified; however, 47% of 94 ticks collected from Kansas and 73% of 122 ticks from Oklahoma were infected with "Candidatus Rickettsia andeanae" a spotted fever group Rickettsia species of undetermined pathogenicity. These preliminary data suggest that "Ca. R. andeanae" is well-adapted to survival in populations of A. maculatum in Kansas and Oklahoma, and that its ubiquity in Gulf Coast ticks in these states may effectively exclude R. parkeri from their shared arthropod host, which could diminish markedly or preclude entirely the occurrence of R. parkeri rickettsiosis in this region of the United States. PMID:25773931

  14. High prevalence of "Candidatus Rickettsia andeanae" and apparent exclusion of Rickettsia parkeri in adult Amblyomma maculatum (Acari: Ixodidae) from Kansas and Oklahoma.

    Science.gov (United States)

    Paddock, Christopher D; Denison, Amy M; Dryden, Michael W; Noden, Bruce H; Lash, R Ryan; Abdelghani, Sarah S; Evans, Anna E; Kelly, Aubree R; Hecht, Joy A; Karpathy, Sandor E; Ganta, Roman R; Little, Susan E

    2015-04-01

    Amblyomma maculatum (the Gulf Coast tick), an aggressive, human-biting, Nearctic and Neotropical tick, is the principal vector of Rickettsia parkeri in the United States. This pathogenic spotted fever group Rickettsia species has been identified in 8-52% of questing adult Gulf Coast ticks in the southeastern United States. To our knowledge, R. parkeri has not been reported previously from adult specimens of A. maculatum collected in Kansas or Oklahoma. A total of 216 adult A. maculatum ticks were collected from 18 counties in Kansas and Oklahoma during 2011-2014 and evaluated by molecular methods for evidence of infection with R. parkeri. No infections with this agent were identified; however, 47% of 94 ticks collected from Kansas and 73% of 122 ticks from Oklahoma were infected with "Candidatus Rickettsia andeanae" a spotted fever group Rickettsia species of undetermined pathogenicity. These preliminary data suggest that "Ca. R. andeanae" is well-adapted to survival in populations of A. maculatum in Kansas and Oklahoma, and that its ubiquity in Gulf Coast ticks in these states may effectively exclude R. parkeri from their shared arthropod host, which could diminish markedly or preclude entirely the occurrence of R. parkeri rickettsiosis in this region of the United States.

  15. 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.

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

    Science.gov (United States)

    Hendry, Tory A; Hunter, Martha S; Baltrus, David A

    2014-12-01

    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.

  18. Isolation of the rickettsial agent genetically similar to Candidatus Rickettsia kotlanii, from Haemaphysalis megaspinosa in Japan.

    Science.gov (United States)

    Andoh, Masako; Ogasawara, Yumiko; Sakata, Akiko; Ito, Takuya; Fujita, Hiromi; Kawabata, Hiroki; Ando, Shuji

    2014-09-01

    Two rickettsial isolates, HM-1 and HM-2, were isolated from Haemaphysalis megaspinosa collected in Japan in 2006 and 2011, respectively. The isolates were analyzed by DNA sequences of the outer membrane protein A gene, the outer membrane protein B gene, the citrate synthase gene, the genus Rickettsia-specific outer membrane protein 17-kDa gene, the 16S ribosome RNA gene, and the PS120 protein gene ("geneD"). HM-1 was identified as Rickettsia tamurae. HM-2 matched most closely with 'Candidatus Rickettsia kotlanii' DNA, which has only been reported from H. concinna in Hungary. This is the first report of isolation in Japan of the agent genetically similar to 'Candidatus R. kotlanii,' which belongs phylogenetically to the spotted fever group Rickettsia. Our study shows the possibility that 'Candidatus R. kotlanii' can be carried by at least two tick species. Furthermore, because the Rickettsia sp. has been found two distant countries, Hungary and Japan, it has potential for wider distribution.

  19. Molecular characterization of 'Candidatus Rickettsia vini' in Ixodes arboricola from the Czech Republic and Slovakia.

    Science.gov (United States)

    Novakova, Marketa; Bulkova, Alexandra; Costa, Francisco B; Kristin, Anton; Krist, Milos; Krause, Frantisek; Liznarova, Eva; Labruna, Marcelo B; Literak, Ivan

    2015-04-01

    The aim of this study was to analyze the prevalence of rickettsiae in the tree-hole tick Ixodes arboricola in the Czech Republic and Slovakia. During May to September of 2009 and 2013, bird boxes belonging to three different areas were screened for ticks. In total, 454 nestlings and 109 nests of 10 hole-breeding bird species were examined. Ticks were found on Ficedula albicollis, Parus major, Cyanistes caeruleus and Sitta europaea and/or in their nests. In total, 166 ticks (17 nymphs, 10 males and 139 females) were found at 3 areas (arithmetic mean±standard error: 55.3±45.9). All ticks were tested for the presence of Rickettsia species by polymerase chain reaction targeting the rickettsial genes gltA, ompA, ompB and htrA and amplicon sequencing. All individuals except 3 nymphs were infected with 'Candidatus Rickettsia vini'. Multilocus sequence typing showed closest proximity to Rickettsia japonica and Rickettsia heilongjiangensis cluster. The presence of 'Ca. R. vini' is reported for the first time in Slovakia.

  20. 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.

  1. 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.

  2. Thoracic radiographic findings in dogs infected with Rickettsia rickettsii

    International Nuclear Information System (INIS)

    Sixteen beagle dogs were injected intradermally with Rickettsia rickettsii. The dogs were divided into four groups (n = 4): 1) infected, non-treated control; 2) infected, treated with doxycycline; 3) infected, treated with doxycycline and an anti-inflammatory dose of corticosteroid; and 4) infected, treated with doxycycline and an immunosuppressive dose of corticosteroid. Thoracic radiographs were made and ocular fluorescein angiography was performed on days 6, 10, 17 post-inoculation. A mild interstitial lung opacity was noted in 4/16 dogs on day 6, 5/16 on day 10 and 3/16 on day 17 post-inoculation. Increased retinal vascular permeability was noted in 8/16 dogs on day 6, 3/16 on day 10 and 1/16 on day 17 post-inoculation. Correlation between the presence of radiographic and retinal lesions was not significant (p = 0.08). Eleven, naturally infected, dogs with thoracic radiographs and a final diagnosis of RMSF were also evaluated. Four of the 11 dogs had an unstructured interstitial pattern. Dogs with acute, experimentally-infected or naturally-occurring RMSF may have subtle pulmonary changes characterized by an unstructured interstitial pattern

  3. Rickettsia africae in Hyalomma dromedarii ticks from sub-Saharan Algeria.

    Science.gov (United States)

    Kernif, Tahar; Djerbouh, Amel; Mediannikov, Oleg; Ayach, Bouhous; Rolain, Jean-Marc; Raoult, Didier; Parola, Philippe; Bitam, Idir

    2012-12-01

    Spotted fever group (SFG) rickettsioses are caused by obligate, intracellular Gram-negative bacteria of the genus Rickettsia. In recent years, several species and subspecies of rickettsias have been identified as emerging pathogens throughout the world, including sub-Saharan Africa. We report here the detection of Rickettsia africae, the agent responsible for African tick-bite fever, by amplification of fragments of gltA and ompA genes and multi-spacer typing from Hyalomma dromedarii ticks collected from the camel Camelus dromedarius in the Adrar and Béchar region (sub-Saharan Algeria). To date, R. africae has been associated mainly with Amblyomma spp. The role of H. dromedarii in the epidemiology of R. africae requires further investigation.

  4. "Rickettsia amblyommii" induces cross protection against lethal Rocky Mountain spotted fever in a guinea pig model.

    Science.gov (United States)

    Blanton, Lucas S; Mendell, Nicole L; Walker, David H; Bouyer, Donald H

    2014-08-01

    Rocky Mountain spotted fever (RMSF) is a severe illness caused by Rickettsia rickettsii for which there is no available vaccine. We hypothesize that exposure to the highly prevalent, relatively nonpathogenic "Rickettsia amblyommii" protects against R. rickettsii challenge. To test this hypothesis, guinea pigs were inoculated with "R. amblyommii." After inoculation, the animals showed no signs of illness. When later challenged with lethal doses of R. rickettsii, those previously exposed to "R. amblyommii" remained well, whereas unimmunized controls developed severe illness and died. We conclude that "R. amblyommii" induces an immune response that protects from illness and death in the guinea pig model of RMSF. These results provide a basis for exploring the use of low-virulence rickettsiae as a platform to develop live attenuated vaccine candidates to prevent severe rickettsioses.

  5. The Rickettsia Endosymbiont of Ixodes pacificus Contains All the Genes of De Novo Folate Biosynthesis.

    Directory of Open Access Journals (Sweden)

    Daniel J Hunter

    Full Text Available Ticks and other arthropods often are hosts to nutrient providing bacterial endosymbionts, which contribute to their host's fitness by supplying nutrients such as vitamins and amino acids. It has been detected, in our lab, that Ixodes pacificus is host to Rickettsia species phylotype G021. This endosymbiont is predominantly present, and 100% maternally transmitted in I. pacificus. To study roles of phylotype G021 in I. pacificus, bioinformatic and molecular approaches were carried out. MUMmer genome alignments of whole genome sequence of I. scapularis, a close relative to I. pacificus, against completely sequenced genomes of R. bellii OSU85-389, R. conorii, and R. felis, identified 8,190 unique sequences that are homologous to Rickettsia sequences in the NCBI Trace Archive. MetaCyc metabolic reconstructions revealed that all folate gene orthologues (folA, folC, folE, folKP, ptpS required for de novo folate biosynthesis are present in the genome of Rickettsia buchneri in I. scapularis. To examine the metabolic capability of phylotype G021 in I. pacificus, genes of the folate biosynthesis pathway of the bacterium were PCR amplified using degenerate primers. BLAST searches identified that nucleotide sequences of the folA, folC, folE, folKP, and ptpS genes possess 98.6%, 98.8%, 98.9%, 98.5% and 99.0% identity respectively to the corresponding genes of Rickettsia buchneri. Phylogenetic tree constructions show that the folate genes of phylotype G021 and homologous genes from various Rickettsia species are monophyletic. This study has shown that all folate genes exist in the genome of Rickettsia species phylotype G021 and that this bacterium has the genetic capability for de novo folate synthesis.

  6. Tick cell culture isolation and growth of Rickettsia raoultii from Dutch Dermacentor reticulatus ticks.

    Science.gov (United States)

    Alberdi, M Pilar; Nijhof, Ard M; Jongejan, Frans; Bell-Sakyi, Lesley

    2012-12-01

    Tick cell lines play an important role in research on ticks and tick-borne pathogenic and symbiotic microorganisms. In an attempt to derive continuous Dermacentor reticulatus cell lines, embryo-derived primary cell cultures were set up from eggs laid by field ticks originally collected as unfed adults in The Netherlands and maintained for up to 16 months. After several months, it became evident that cells in the primary cultures were infected with a Rickettsia-like intracellular organism. Supernatant medium containing some D. reticulatus cells was inoculated into cultures of 2 Rhipicephalus (Boophilus) microplus cell lines, BME/CTVM2 and BME/CTVM23, where abundant growth of the bacteria occurred intracellularly on transfer to both cell lines. Bacterial growth was monitored by light (live, inverted microscope, Giemsa-stained cytocentrifuge smears) and transmission electron microscopy revealing heavy infection with typical intracytoplasmic Rickettsia-like bacteria, not present in uninfected cultures. DNA was extracted from bacteria-infected and uninfected control cultures, and primers specific for Rickettsia 16S rRNA, ompB, and sca4 genes were used to generate PCR products that were subsequently sequenced. D. reticulatus primary cultures and both infected tick cell lines were positive for all 3 Rickettsia genes. Sequencing of PCR products revealed 99-100% identity with published Rickettsia raoultii sequences. The R. raoultii also grew abundantly in the D. nitens cell line ANE58, poorly in the D. albipictus cell line DALBE3, and not at all in the D. andersoni cell line DAE15. In conclusion, primary tick cell cultures and cell lines are useful systems for isolation and propagation of fastidious tick-borne microorganisms. In vitro isolation of R. raoultii from Dutch D. reticulatus confirms previous PCR-based detection in field ticks, and presence of the bacteria in the tick eggs used to initiate the primary cultures confirms that transovarial transmission of this

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Amblyomma maculatum Feeding Augments Rickettsia parkeri Infection in a Rhesus Macaque Model: A Pilot Study.

    Science.gov (United States)

    Banajee, Kaikhushroo H; Embers, Monica E; Langohr, Ingeborg M; Doyle, Lara A; Hasenkampf, Nicole R; Macaluso, Kevin R

    2015-01-01

    Rickettsia parkeri is an emerging eschar-causing human pathogen in the spotted fever group of Rickettsia and is transmitted by the Gulf coast tick, Amblyomma maculatum. Tick saliva has been shown to alter both the cellular and humoral components of the innate and adaptive immune systems. However, the effect of this immunomodulation on Rickettsia transmission and pathology in an immunocompetent vertebrate host has not been fully examined. We hypothesize that, by modifying the host immune response, tick feeding enhances infection and pathology of pathogenic spotted fever group Rickettsia sp. In order to assess this interaction in vivo, a pilot study was conducted using five rhesus macaques that were divided into three groups. One group was intradermally inoculated with low passage R. parkeri (Portsmouth strain) alone (n = 2) and another group was inoculated during infestation by adult, R. parkeri-free A. maculatum (n = 2). The final macaque was infested with ticks alone (tick feeding control group). Blood, lymph node and skin biopsies were collected at several time points post-inoculation/infestation to assess pathology and quantify rickettsial DNA. As opposed to the tick-only animal, all Rickettsia-inoculated macaques developed inflammatory leukograms, elevated C-reactive protein concentrations, and elevated TH1 (interferon-γ, interleukin-15) and acute phase inflammatory cytokines (interleukin-6) post-inoculation, with greater neutrophilia and interleukin-6 concentrations in the tick plus R. parkeri group. While eschars formed at all R. parkeri inoculation sites, larger and slower healing eschars were observed in the tick feeding plus R. parkeri group. Furthermore, dissemination of R. parkeri to draining lymph nodes early in infection and increased persistence at the inoculation site were observed in the tick plus R. parkeri group. This study indicates that rhesus macaques can be used to model R. parkeri rickettsiosis, and suggests that immunomodulatory factors

  9. 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.

  10. Seroprevalence of Rickettsia bellii and Rickettsia felis in dogs, São José dos Pinhais, State of Paraná, Brazil Soroprevalência de Rickettsia bellii e Rickettsia felis em cães, São José dos Pinhais, Paraná, Brasil

    OpenAIRE

    Fernanda Silva Fortes; Iara Silveira; Jonas Moraes-Filho; Ronaldo Viana Leite; José Edivaldo Bonacim; Alexander Welker Biondo; Marcelo Bahia Labruna; Marcelo Beltrão Molento

    2010-01-01

    Brazilian spotted fever (BSF) is a vector-borne zoonosis caused by Rickettsia rickettsii bacteria. Dogs can be host sentinels for this bacterium. The aim of the study was to determine the presence of antibodies against Rickettsia spp. in dogs from the city of São José dos Pinhais, State of Paraná, Southern Brazil, where a human case of BSF was first reported in the state. Between February 2006 and July 2007, serum samples from 364 dogs were collected and tested at 1:64 dilutions by indirect i...

  11. Survey for hantaviruses, tick-borne encephalitis virus, and Rickettsia spp. in small rodents in Croatia.

    Science.gov (United States)

    Svoboda, Petra; Dobler, Gerhard; Markotić, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinović, Lidija Cvetko; Tadin, Ante; Margaletić, Josip; Essbauer, Sandra

    2014-07-01

    In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunofluorescence assays (IIFT) and for nucleic acids by conventional (hantaviruses) and real-time RT-/PCRs (TBEV and Rickettsia spp.). A total of 25.5% (24/94) of the rodents from the mountainous area revealed specific antibodies against hantaviruses. In all, 21.3% (20/94) of the samples from the mountainous area and 29.0% (9/31) from the lowland area yielded positive results for either Puumala virus (PUUV) or Dobrava-Belgrade virus (DOBV) using a conventional RT-PCR. All processed samples (n=194) were negative for TBEV by IIFT or real-time RT-PCR. Serological evidence of rickettsial infection was detected in 4.3% (4/94) rodents from the mountainous region. Another 3.2% (3/94) rodents were positive for Rickettsia spp. by real-time PCR. None of the rodents (n=76) from the lowland area were positive for Rickettsia spp. by real-time PCR. Dual infection of PUUV and Rickettsia spp. was found in one M. glareolus from the mountainous area by RT-PCR and real-time PCR, respectively. To our knowledge, this is the first detection of Rickettsia spp. in small rodents from Croatia. Phylogenetic analyses of S- and M-segment sequences obtained from the two study sites revealed well-supported subgroups in Croatian PUUV and DOBV. Although somewhat limited, our data showed occurrence and prevalence of PUUV, DOBV, and rickettsiae in Croatia. Further studies are warranted to confirm these data and to determine the Rickettsia species present in rodents in these areas.

  12. Survey for hantaviruses, tick-borne encephalitis virus, and Rickettsia spp. in small rodents in Croatia.

    Science.gov (United States)

    Svoboda, Petra; Dobler, Gerhard; Markotić, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinović, Lidija Cvetko; Tadin, Ante; Margaletić, Josip; Essbauer, Sandra

    2014-07-01

    In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunofluorescence assays (IIFT) and for nucleic acids by conventional (hantaviruses) and real-time RT-/PCRs (TBEV and Rickettsia spp.). A total of 25.5% (24/94) of the rodents from the mountainous area revealed specific antibodies against hantaviruses. In all, 21.3% (20/94) of the samples from the mountainous area and 29.0% (9/31) from the lowland area yielded positive results for either Puumala virus (PUUV) or Dobrava-Belgrade virus (DOBV) using a conventional RT-PCR. All processed samples (n=194) were negative for TBEV by IIFT or real-time RT-PCR. Serological evidence of rickettsial infection was detected in 4.3% (4/94) rodents from the mountainous region. Another 3.2% (3/94) rodents were positive for Rickettsia spp. by real-time PCR. None of the rodents (n=76) from the lowland area were positive for Rickettsia spp. by real-time PCR. Dual infection of PUUV and Rickettsia spp. was found in one M. glareolus from the mountainous area by RT-PCR and real-time PCR, respectively. To our knowledge, this is the first detection of Rickettsia spp. in small rodents from Croatia. Phylogenetic analyses of S- and M-segment sequences obtained from the two study sites revealed well-supported subgroups in Croatian PUUV and DOBV. Although somewhat limited, our data showed occurrence and prevalence of PUUV, DOBV, and rickettsiae in Croatia. Further studies are warranted to confirm these data and to determine the Rickettsia species present in rodents in these areas. PMID:24866325

  13. Linfadenitis por vacuna de bacilo Calmette-Guérin

    Directory of Open Access Journals (Sweden)

    Armando Reyes-Cadena

    2015-03-01

    Full Text Available La linfadenitis por vacunación con bacilo de Calmette-Guérin (BCG es la complicación más frecuente de esta vacuna. Se define como el crecimiento de los ganglios linfáticos regionales ipsilaterales posteriores a la vacunación, su incidencia se estima en < 0.4/1 000 vacunados menores de 1 año y en 0.03/1 000 vacunados de entre 1 y 20 años de edad.1 Se recomienda que este término se utilice cuando el crecimiento ganglionar se palpe con facilidad, el paciente se mantenga afebril y en buen estado general. Se manifiesta con mucha frecuencia entre las 2 semanas y los 6 meses después de la aplicación de la vacuna y la gran mayoría ocurre en un lapso de 24 meses.2,3

  14. Rickettsia infection in five areas of the state of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Maurício C Horta

    2007-11-01

    Full Text Available This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi, and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting fleas, whereas Rickettsia bellii was the only agent infecting ticks, but no animal or human blood was shown to contain rickettsial DNA. Testing animal and human sera by indirect immunofluorescence assay against four rickettsia antigens (R. rickettsii, R. parkeri, R. felis, and R. bellii, some opossum, dog, horse, and human sera reacted to R. rickettsii with titers at least four-fold higher than to the other three rickettsial antigens. These sera were considered to have a predominant antibody response to R. rickettsii. Using the same criteria, opossum, dog, and horse sera showed predominant antibody response to R. parkeri or a very closely related genotype. Our serological results suggest that both R. rickettsii and R. parkeri infected animals and/or humans in the studied areas.

  15. Detection of Rickettsia helvetica in Ixodes ricinus ticks collected from Pyrenean chamois in France.

    Science.gov (United States)

    Davoust, Bernard; Socolovschi, Cristina; Revelli, Paul; Gibert, Philippe; Marié, Jean-Lou; Raoult, Didier; Parola, Philippe

    2012-12-01

    Seventy-one Ixodes ricinus ticks collected from Pyrenean chamois (Rupicapra pyrenaica) in the French Pyrenees were tested by real-time polymerase chain reaction to detect the presence of Rickettsia and Bartonella. Four ticks (6%) were positive for R. helvetica. The chamois carries infected ticks, and this enables the dissemination throughout the environment with this bacterium, a potential human pathogen.

  16. 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.

  17. Draft Genome Sequence of a New Zealand Rickettsia-Like Organism Isolated from Farmed Chinook Salmon

    Science.gov (United States)

    Draper, Jenny; Brosnahan, Cara L.; Orr, Della; McFadden, Andrew; Jones, Brian

    2016-01-01

    We report here the draft genome sequence of a rickettsia-like organism, isolated from a New Zealand Chinook salmon farm experiencing high mortality. The genome is approximately 3 Mb in size, has a G+C content of approximately 39.2%, and is predicted to contain 2,870 coding sequences. PMID:27365345

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

    Science.gov (United States)

    Chahota, R; Thakur, S D; Sharma, M; Mittra, S

    2015-01-01

    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.

  19. Isolation and maintenance of Rickettsia raoultii in a Rhipicephalus sanguineus tick cell line.

    Science.gov (United States)

    Santibáñez, Sonia; Portillo, Aránzazu; Palomar, Ana M; Bell-Sakyi, Lesley; Romero, Lourdes; Oteo, José A

    2015-01-01

    Rickettsia raoultii, a member of the spotted fever group rickettsiae, has been implicated in cases of DEBONEL/TIBOLA/SENLAT, and has been detected in Dermacentor spp. and Rhipicephalus pumilio ticks by PCR. R. raoultii has been isolated in mammalian and tick cell lines. This study aimed to isolate R. raoultii from Spanish Dermacentor marginatus in tick cell lines. A single adult D. marginatus collected from vegetation in La Rioja (Northen Spain) in October 2012 was surface-sterilised, triturated and aliquots of the homogenate were inoculated into a panel of tick cell lines derived from embryonic Rhipicephalus sanguineus, Rhipicephalus evertsi and Ixodes ricinus. Cultures were maintained at 28 °C with weekly medium changes and checked by Gimenez stain for Rickettsia-like intracellular organisms. After 50 days of incubation, intracellular Rickettsia-like organisms were observed in the R. sanguineus cell line RML-RSE using Gimenez stain. PCR assays and sequencing of fragments of 16S RNA, ompB and ompA genes in DNA extracted from the culture suspension showed 100% identity with R. raoultii. Growth of intracellular microorganisms was not observed in preparations of the other tick cell lines. In conclusion, the tick cell line RML-RSE is a useful system for the isolation and maintenance of R. raoultii.

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

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  1. Novel Candidatus rickettsia species detected in nostril tick from human, Gabon, 2014.

    Science.gov (United States)

    Lopez-Velez, Rogelio; Palomar, Ana M; Oteo, José A; Norman, Francesca F; Pérez-Molina, José A; Portillo, Aránzazu

    2015-02-01

    We report the identification of a nymphal nostril tick (Amblyomma sp.) from a national park visitor in Gabon and subsequent molecular detection and characterization of tickborne bacteria. Our findings provide evidence of a potentially new Rickettsia sp. circulating in Africa and indicate that tick bites may pose a risk to persons visiting parks in the region.

  2. Seroepidemiological survey of Rickettsia spp. in dogs from the endemic area of Rickettsia parkeri rickettsiosis in Uruguay.

    Science.gov (United States)

    Lado, Paula; Costa, Francisco B; Verdes, José M; Labruna, Marcelo B; Venzal, José M

    2015-06-01

    Rickettsia parkeri rickettsiosis is a vector-borne zoonosis that occurs in some countries of the American continent. Following the first description and determination of the pathogenicity to humans in 2004 in USA, this bacterium has been reported in several South American countries. Human cases have been diagnosed in both Uruguay and Argentina in the past years. This study consisted in a serosurvey of 1000 domestic dogs living in the endemic area of rickettsiosis in Uruguay, where Amblyomma triste is the tick vector. Sera were analyzed by Indirect Immunofluorescence Assay (IFA), against antigens of three different rickettsial species: R. rhipicephali, R. felis and R. parkeri. It was determined that 20.3% of the dogs had antibodies that reacted to at least one of the three species tested, taking as cut off ≥64 titers. Furthermore, 140 of the seropositive dogs (14%) had a titer at least 4 times higher to R. parkeri than those of any of the other species, thus, it was considered that the immune response was stimulated by that species in particular. This is the first serological survey in primary hosts for adults of A. triste in Uruguay, and therefore the first prevalence values are reported. Adult A. triste ticks collected from the environment as well as from dogs were analyzed by PCR in order to confirm the current circulation of the agent in the area. In this matter, two out of 28 ticks from dogs, and 3 out of 53 ticks from the environment were positive, and the corresponding sequence analysis revealed 100% similarity with R. parkeri strain maculatum. PMID:25735816

  3. Seroepidemiological survey of Rickettsia spp. in dogs from the endemic area of Rickettsia parkeri rickettsiosis in Uruguay.

    Science.gov (United States)

    Lado, Paula; Costa, Francisco B; Verdes, José M; Labruna, Marcelo B; Venzal, José M

    2015-06-01

    Rickettsia parkeri rickettsiosis is a vector-borne zoonosis that occurs in some countries of the American continent. Following the first description and determination of the pathogenicity to humans in 2004 in USA, this bacterium has been reported in several South American countries. Human cases have been diagnosed in both Uruguay and Argentina in the past years. This study consisted in a serosurvey of 1000 domestic dogs living in the endemic area of rickettsiosis in Uruguay, where Amblyomma triste is the tick vector. Sera were analyzed by Indirect Immunofluorescence Assay (IFA), against antigens of three different rickettsial species: R. rhipicephali, R. felis and R. parkeri. It was determined that 20.3% of the dogs had antibodies that reacted to at least one of the three species tested, taking as cut off ≥64 titers. Furthermore, 140 of the seropositive dogs (14%) had a titer at least 4 times higher to R. parkeri than those of any of the other species, thus, it was considered that the immune response was stimulated by that species in particular. This is the first serological survey in primary hosts for adults of A. triste in Uruguay, and therefore the first prevalence values are reported. Adult A. triste ticks collected from the environment as well as from dogs were analyzed by PCR in order to confirm the current circulation of the agent in the area. In this matter, two out of 28 ticks from dogs, and 3 out of 53 ticks from the environment were positive, and the corresponding sequence analysis revealed 100% similarity with R. parkeri strain maculatum.

  4. 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.

  5. "Rickettsia amblyommii" and R. montanensis infection in dogs following natural exposure to ticks.

    Science.gov (United States)

    Barrett, Anne; Little, Susan E; Shaw, Edward

    2014-01-01

    To determine the risk of canine infection with spotted fever group (SFG) Rickettsia spp. following natural tick exposure, 10 dogs determined to be free of evidence of exposure to or infection with tick-borne disease agents were exposed to ticks via weekly walks in a wooded area in north-central Oklahoma. After each walk, dogs were examined and the number and species of ticks present were recorded. The dogs were then returned to outdoor kennels to allow the infestations and subsequent transmission of any pathogens to proceed. Serum samples and whole blood were collected from each dog twice weekly for 121 days and evaluated via indirect fluorescence antibody (IFA) for antibodies reactive to Rickettsia rickettsii, R. montanensis, and "R. amblyommii," and by PCR for evidence of Rickettsia spp. Dogs became infested with a total of 57-108 ticks over the entire 8-week infestation period (weekly average tick infestation=12.0±4.1). The great majority of the ticks present were Amblyomma americanum (90.5%), with a small number of Dermacentor variabilis and A. maculatum also identified. All (10/10) dogs seroconverted to R. rickettsii, R. montanensis, and "R. amblyommii," with mean maximum inverse titers of 1176, 1448, and 6654, respectively, for all dogs in the study. Maximum inverse titers to "R. amblyommii" ranged from 4096 to 16,384 and were higher in 9/10 dogs than maximum inverse titers to R. rickettsii or R. montanensis. Sequence-confirmed SFG Rickettsia spp. (R. montanensis and "R. amblyommii") were occasionally, but not consistently, identified from whole blood by PCR. Taken together, our data suggest that, in areas where A. americanum is common, antibodies reactive to R. rickettsii in dogs may be due instead to infection with "R. amblyommii" or other, closely related SFG Rickettsia spp.

  6. 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.

  7. Serological identification of Rickettsia spp from the spotted fever group in capybaras in the region of Campinas - SP - Brazil Identificação sorológica de Rickettsia spp do grupo da febre maculosa em capivaras na região de Campinas, SP, Brasil

    Directory of Open Access Journals (Sweden)

    Celso Eduardo de Souza

    2008-09-01

    Full Text Available Diseases transmitted by ticks have been an important health problem all over the world. Brazilian Spotted Fever (BSF stands for a serious epidemiological concern due to the high mortality rates pointed out. Capybaras are commonly incriminated as possible reservoirs in the BSF transmission cycle. In the last decades the numbers of these animals raised sharply and they have invaded human areas. They intensify the contact between ticks and humans beings. This study aim is to contribute to the possible role performed for this rodent in the BSF epidemiology in some areas located in Campinas region, São Paulo. Cabybaras infected by rickettsiae of BSF group were studied through the analysis of the frequencies of BSF-group rickettisae antibodies titer = 64 by indirect immunofluorescence test (IFA, and data from human cases epidemiological surveillance. The serum frequency positiveness varied greatly according to areas where animals were captured. However it was found serum positiviness only in the areas where human cases of BSF were reported. These findings suggest the capybara may be seen as sentinel animal. Due to presence of serological cross reactivity between microorganisms belonging to SF group, the results must be interpreted carefully and additional methods to distinguish pathogenic rickettsiae are required in our country.Doenças transmitidas por carrapatos vêm sendo um importante problema de saúde pública no mundo. A Febre Maculosa Brasileira (FMB representa um sério risco epidemiológico devido às altas taxas de letalidade apresentadas. As capivaras são freqüentemente incriminadas como possíveis reservatórios no ciclo de transmissão da FMB. Nas últimas décadas o número desses animais cresceu intensamente e eles invadiram os espaços humanos. As capivaras intensificam o contato entre carrapatos e seres humanos na medida em que se apresentam muito infestadas por estes parasitos. O objetivo deste estudo é contribuir para o

  8. 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.

  9. Detection of Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in hard ticks (Acari, Ixodidae) parasitizing bats in Poland

    OpenAIRE

    Piksa, Krzysztof; Stańczak, Joanna; Biernat, Beata; Górz, Andrzej; Nowak-Chmura, Magdalena; Siuda, Krzysztof

    2016-01-01

    A total of 491 Ixodes vespertilionis and 8 Ixodes ricinus collected from bats and cave walls in southern Poland between 2010 and 2012 were examined by the polymerase chain reaction for tick-transmitted pathogens. PCR analysis for Borrelia burgdorferi s.l., Rickettsia spp., and Anaplasma phagocytophilum yielded negative results for all I. vespertilionis. DNA of Rickettsia helvetica was detected in three specimens of I. ricinus attached to Rhinolophus hipposideros or Myotis myotis, while Borrel...

  10. Sympatric occurrence of Ixodes ricinus, Dermacentor reticulatus and Haemaphysalis concinna ticks and Rickettsia and Babesia species in Slovakia.

    Science.gov (United States)

    Svehlová, Andrea; Berthová, Lenka; Sallay, Balázs; Boldiš, Vojtech; Sparagano, Olivier A E; Spitalská, Eva

    2014-09-01

    Vojka nad Dunajom in the south-west of the Slovak Republic is a locality with sympatric occurrence of 3 species of ticks. This study investigated the spatial distribution of Dermacentor reticulatus, Ixodes ricinus, and Haemaphysalis concinna ticks in this area and determined the prevalence of Babesia and Rickettsia species in questing adults of these tick species considered as potential risk for humans and animals. Ticks were collected by blanket dragging over the vegetation from September 2011 to October 2012. All ticks were subjected to DNA extraction and individually assayed with PCR-based methods targeting the gltA, sca4, 23S rRNA genes of Rickettsia spp. and the 18S rRNA gene of Babesia spp. D. reticulatus was the dominant species occurring in this area (67.7%, n=600), followed by I. ricinus (31.8%, n=282) and H. concinna (0.5%, n=4) ticks. Rickettsial infection was determined in 10.8% (n=65) and 11.7% (n=33) of D. reticulatus and I. ricinus ticks, respectively. Babesia spp. infection was confirmed in 1.8% (n=11) of D. reticulatus and 0.4% (n=1) of I. ricinus ticks. DNA of 6 different pathogenic tick-borne species, Rickettsia helvetica, Rickettsia monacensis, Rickettsia slovaca, Rickettsia raoultii, Babesia canis, and Babesia venatorum were identified in this locality with sympatric occurrence of I. ricinus, D. reticulatus, and H. concinna ticks.

  11. Isolation by a sensitive centrifugation cell culture system of 52 strains of spotted fever group rickettsiae from ticks collected in France.

    OpenAIRE

    Péter, O; Raoult, D.; Gilot, B.

    1990-01-01

    Boutonneuse fever caused by Rickettsia conorii is transmitted mainly by the brown dog tick, Rhipicephalus sanguineus. We collected 540 ticks in Marseille, France, and tried to isolate as many strains of rickettsia as possible. Ticks were evaluated for the presence of rickettsia by the hemolymph test and by a new culture system, the centrifugation-shell vial technique. We avoided contamination in the culture system. Prior to ticks being submitted to the hemolymph test, they were disinfected. O...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Tests on ticks from wild birds collected in the eastern United States for rickettsiae and viruses

    Science.gov (United States)

    Clifford, C.M.; Sonenshine, D.E.; Atwood, E.L.; Robbins, C.S.; Hughes, L.E.

    1969-01-01

    Results of tests for rickettsiae and viruses on 4,266 ticks taken from more than 10,000 birds, comprising 150 species, in the eastern United States indicated the presence of two agents: Rickettsia rickettsii and an agent of the typhus group. Infection with R. rickettsii was indicated in 24 pools of Haemaphysalis leporispalustris, five pools of Ixodes dentatus, one pool of Ixodes brunneus, and two pools that contained both I. dentatus and H. leporispalustris. The pools positive for R. rickettsii were from a variety of locations in the eastern U. S. The typhus-group agent was demonstrated only once, in a single pool of H. leporispalustris taken at Kent Point, Maryland. A strain of R. rickettsii was isolated from a pool of 21 larval H. leporispalustris collected at Ocean City, Maryland. This agent possessed several characteristics of other strains of low virulence isolated previously in this region by various authors.

  14. Defending the fort: a role for defensin-2 in limiting Rickettsia montanensis infection of Dermacentor variabilis.

    Science.gov (United States)

    Pelc, R S; McClure, J C; Sears, K T; Chung, A; Rahman, M S; Ceraul, S M

    2014-08-01

    The importance of tick defensins is evidenced by their expression in a wide variety of tick tissues and prevalence across many tick genera. To date, the functional and biological significance of defensin-2 as a rickettsiastatic or rickettsiacidal antimicrobial peptide has not been addressed. In a previous study, defensin-2 transcription was shown to increase in Dermacentor variabilis ticks challenged with Rickettsia montanensis. In the present study, the hypothesis that defensin-2 is functional as a rickettsiastatic and/or rickettsiacidal antimicrobial peptide is tested. We show that defensin-2 plays a role in reducing burden after acquisition of Rickettsia montanensis through capillary feeding. Moreover, defensin-2 is shown to associate with R. montanensis in vitro and in vivo, causing cytoplasmic leakiness.

  15. Discovery of Rickettsia species in Dermacentor niveus Neumann ticks by investigating the diversity of bacterial communities.

    Science.gov (United States)

    Zhuang, Lu; Wang, Cheng-Yan; Tong, Yi-Gang; Tang, Fang; Yang, Hong; Liu, Wei; Cao, Wu-Chun

    2014-09-01

    Ticks (Dermacentor niveus Neumann) were collected from Tacheng, Xinjiang Uygur Autonomous Region, and their bacterial diversity was investigated using the 16S RNA gene library method from one pooled sample. A total of 452 clones was successfully sequenced and assigned to 4 phyla. The dominant phylum was the Proteobacteria, accounting for 62.8% of all the clones of the 16S rRNA gene at the confidence level 80%. The other sequences were assigned to the phyla Bacteroidetes, Firmicutes, Actinobacteria and accounted for 13.5%, 12.4%, and 11.3%, respectively. These results provide an insight into the bacterial diversity associated with D. niveus ticks in the natural environment of Tacheng. They indicate the occurrence of Rickettsia raoultii and Rickettsia slovaca in D. niveus ticks in this area, and as a consequence, cases of TIBOLA/DEBONEL may occur (tick-borne lymphadenopathy/Dermacentor-borne necrosis erythema and lymphadenopathy).

  16. First molecular detection of Rickettsia parkeri in Amblyomma tigrinum and Amblyomma dubitatum ticks from Uruguay.

    Science.gov (United States)

    Lado, Paula; Castro, Oscar; Labruna, Marcelo B; Venzal, José M

    2014-10-01

    Rickettsia parkei is the etiological agent of spotted fever in Uruguay, where is transmitted to humans by the tick Amblyomma triste. In the present study, ticks were collected from capybaras (Hydrochoerus hydrochaeris) and domestic dogs during 2011-2012 in different parts of Uruguay. Three out of 11 (27.3%) Amblyomma dubitatum ticks collected from capybaras, and 4 out of 6 (66.7%) Amblyomma tigrinum ticks collected from dogs were shown by molecular analyses to be infected by Rickettsia parkeri strain Maculatum 20. Until the present work, A. triste was the only tick species that was found infected by R. parkeri in Uruguay. This is the first report of R. parkeri infecting these two tick species in Uruguay, expanding the current distribution of this rickettsial pathogen in the country.

  17. Prevalence and Infection Load Dynamics of Rickettsia felis in Actively Feeding Cat Fleas

    OpenAIRE

    Reif, Kathryn E.; Stout, Rhett W.; Gretchen C Henry; Lane D Foil; Macaluso, Kevin R.

    2008-01-01

    Background Rickettsia felis is a flea-associated rickettsial pathogen recurrently identified in both colonized and wild-caught cat fleas, Ctenocephalides felis. We hypothesized that within colonized fleas, the intimate relationship between R. felis and C. felis allows for the coordination of rickettsial replication and metabolically active periods during flea bloodmeal acquisition and oogenesis. Methodology/Principal Findings A quantitative real-time PCR assay was developed to quantify R. fel...

  18. Ehrlichia phagocytophila genogroup rickettsiae in ixodid ticks from California collected in 1995 and 1996.

    OpenAIRE

    Barlough, J E; Madigan, J E; Kramer, V. L.; Clover, J R; Hui, L T; Webb, J P; Vredevoe, L K

    1997-01-01

    A total of 1,246 ixodid ticks collected in 1995 and 1996 from seven California counties were examined for the presence of Ehrlichia phagocytophila genogroup rickettsiae by using a nested PCR technique. Of 1,112 adult Ixodes pacificus Cooley and Kohls ticks tested, nine pools, each containing five ticks, were positive (minimum percentage of ticks harboring detectable ehrlichiae, 0.8%). Positive ticks were limited to four of the seven counties (Sonoma, El Dorado, Santa Cruz, and Orange). In San...

  19. Spotted fever group rickettsiae in ticks and fleas from the Democratic Republic of the Congo

    OpenAIRE

    Mediannikov, Oleg; Davoust, B; Socolovschi, C.; Tshilolo, L.; Raoult, Didier; Parola, P

    2012-01-01

    Little is known about the prevalence of spotted fever group (SFG) rickettsiae in ticks and fleas in the Democratic Republic of the Congo. In 2008, 12 Amblyomma compressum ticks were collected from 3 pangolins (Manis gigantea). Two Haemaphysalis punctaleachi ticks were collected from 2 African civets (Civettictis civetta congica), and one was collected from an antelope (Onotragus leche). A total of 111 Rhipicephalus sanguineus ticks, 23 Ctenocephalides canis fleas, 39 C. felts fleas, and 5 Tri...

  20. Rickettsia prowazekii Transports UMP and GMP, but Not CMP, as Building Blocks for RNA Synthesis

    OpenAIRE

    Winkler, Herbert H.; Daugherty, Robin; Hu, Fuquan

    1999-01-01

    Rickettsia prowazekii, the etiological agent of epidemic typhus, is an obligate intracellular bacterium and is apparently unable to synthesize ribonucleotides de novo. Here, we show that as an alternative, isolated, purified R. prowazekii organisms transported exogenous uridyl- and guanylribonucleotides and incorporated these labeled precursors into their RNA in a rifampin-sensitive manner. Transport systems for nucleotides, which we have shown previously and show here are present in ricketts...

  1. Seasonal analysis of Rickettsia species in ticks in an agricultural site of Slovakia.

    Science.gov (United States)

    Špitalská, Eva; Stanko, Michal; Mošanský, Ladislav; Kraljik, Jasna; Miklisová, Dana; Mahríková, Lenka; Bona, Martin; Kazimírová, Mária

    2016-03-01

    Many rickettsiae of the spotted fever group are emerging pathogens causing serious diseases associated with vertebrate hosts. Ixodidae ticks are known as their vectors. Investigation of the relative abundance of questing Ixodes ricinus and their infection with Rickettsia spp. in an agricultural site comprising a game reserve in Slovakia was the aim of this study. In total, 2198 I. ricinus (492 larvae, 1503 nymphs and 203 adults) were collected by flagging the vegetation along 100 m(2) transects in Rozhanovce (eastern Slovakia): 334, 595 and 1269 in 2011, 2012 and 2013, respectively. Considering questing nymphs and adults, the highest relative density of 81 individuals/100 m(2) was observed in May 2013, the lowest of 0.3 individuals/100 m(2) in March 2012. A total of 1056 ticks (853 nymphs, 100 females and 103 males; 2011: n = 329, 2012: n = 509 and 2013: n = 218) were individually screened by PCR-based methods for the presence of Rickettsia spp. The overall prevalences were 7.3% for nymphs, 15% for females, 7.8% for males; 7.0% in 2011, 8.4% in 2012, and 8.7% in 2013. The maximum prevalences were observed in July in nymphs and in May in adults. Sequencing showed infection with R. helvetica in 73 ticks (72.6% nymphs, 16.4% females, 11% males) and with R. monacensis in 11 ticks (8 nymphs, 3 females). The results showed the circulation of pathogenic Rickettsia species in the agricultural site and a potential risk for humans to encounter infected ticks.

  2. Nonselective Persistence of a Rickettsia conorii Extrachromosomal Plasmid during Mammalian Infection.

    Science.gov (United States)

    Riley, Sean P; Fish, Abigail I; Garza, Daniel A; Banajee, Kaikhushroo H; Harris, Emma K; del Piero, Fabio; Martinez, Juan J

    2016-03-01

    Scientific analysis of the genus Rickettsia is undergoing a rapid period of change with the emergence of viable genetic tools. The development of these tools for the mutagenesis of pathogenic bacteria will permit forward genetic analysis of Rickettsia pathogenesis. Despite these advances, uncertainty still remains regarding the use of plasmids to study these bacteria in in vivo mammalian models of infection, namely, the potential for virulence changes associated with the presence of extrachromosomal DNA and nonselective persistence of plasmids in mammalian models of infection. Here, we describe the transformation of Rickettsia conorii Malish 7 with the plasmid pRam18dRGA[AmTrCh]. Transformed R. conorii stably maintains this plasmid in infected cell cultures, expresses the encoded fluorescent proteins, and exhibits growth kinetics in cell culture similar to those of nontransformed R. conorii. Using a well-established murine model of fatal Mediterranean spotted fever, we demonstrate that R. conorii(pRam18dRGA[AmTrCh]) elicits the same fatal outcomes in animals as its untransformed counterpart and, importantly, maintains the plasmid throughout infection in the absence of selective antibiotic pressure. Interestingly, plasmid-transformed R. conorii was readily observed both in endothelial cells and within circulating leukocytes. Together, our data demonstrate that the presence of an extrachromosomal DNA element in a pathogenic rickettsial species does not affect either in vitro proliferation or in vivo infectivity in models of disease and that plasmids such as pRam18dRGA[AmTrCh] are valuable tools for the further genetic manipulation of pathogenic rickettsiae. PMID:26755154

  3. Survey for Hantaviruses, Tick-Borne Encephalitis Virus, and Rickettsia spp. in Small Rodents in Croatia

    OpenAIRE

    Svoboda, Petra; Dobler, Gerhard; Markotić, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinović, Lidija Cvetko; Tadin, Ante; MARGALETIĆ, JOSIP; Essbauer, Sandra

    2014-01-01

    In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunoflourescence ass...

  4. ISOLATION OF Rickettsia bellii FROM Amblyomma ovale AND Amblyomma incisum TICKS FROM SOUTHERN BRAZIL

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    Richard Pacheco

    2008-08-01

    Full Text Available Objective. To isolate and characterize rickettsiae from the ticks Amblyomma ovale and Amblyomma incisum collected in the state of São Paulo. Materials and methods. Adult, free-living A. ovale and A. incisum were collected in an Atlantic rainforest area in the state of São Paulo, Brazil. Each tick was tested using the hemolymph assay; samples from positive ticks were placed in shell vials in order to isolate rickettsiae and subsequently grown in Vero cells. Amplification of three rickettsial genes (gltA, htrA and ompA was attempted using polymerase chain reaction (PCR for each isolate obtained. Amplicons were subsequently sequenced. Results. A total of 388 A. incisum and 50 A. ovale were collected. Only one A. incisum and one A. ovale were hemolymph-test positive. Rickettsiae were successfully isolated from these ticks; however establishment in Vero cell culture was successful only for the isolate from A. ovale. Bacterial contamination in the first cell passage of the A. incisum isolate precluded successful isolation of the organism. PCR products were obtained with the gltA and htrA primers for the two isolates, but no product was obtained with the ompA primers. By BLAST analysis, partial gltA and htrA sequences of isolates from A. ovale and A. incisum were similar to the corresponding sequences of R. bellii. Conclusions. This is the first report of R. bellii infecting A. incisum and the first successful isolation from A. ovale.

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

    Science.gov (United States)

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

    2016-01-01

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

  6. 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.

  7. Disrupting protein expression with Peptide Nucleic Acids reduces infection by obligate intracellular Rickettsia.

    Science.gov (United States)

    Pelc, Rebecca S; McClure, Jennifer C; Kaur, Simran J; Sears, Khandra T; Rahman, M Sayeedur; Ceraul, Shane M

    2015-01-01

    Peptide Nucleic Acids (PNAs) are single-stranded synthetic nucleic acids with a pseudopeptide backbone in lieu of the phosphodiester linked sugar and phosphate found in traditional oligos. PNA designed complementary to the bacterial Shine-Dalgarno or start codon regions of mRNA disrupts translation resulting in the transient reduction in protein expression. This study examines the use of PNA technology to interrupt protein expression in obligate intracellular Rickettsia sp. Their historically intractable genetic system limits characterization of protein function. We designed PNA targeting mRNA for rOmpB from Rickettsia typhi and rickA from Rickettsia montanensis, ubiquitous factors important for infection. Using an in vitro translation system and competitive binding assays, we determined that our PNAs bind target regions. Electroporation of R. typhi and R. montanensis with PNA specific to rOmpB and rickA, respectively, reduced the bacteria's ability to infect host cells. These studies open the possibility of using PNA to suppress protein synthesis in obligate intracellular bacteria.

  8. Isolation of Rickettsia massiliae from Rhipicephalus sanguineus Ticks, Buenos Aires (Argentina).

    Science.gov (United States)

    Cicuttin, G L; De Salvo, M N; La Rosa, I; Dohmen, F E Gury

    2015-12-01

    Rickettsia massiliae , a member of the spotted fever group of Rickettsia, was first isolated from a Rhipicephalus turanicus tick in France. In the New World, it has been detected in Rhipicephalus sanguineus ticks from different geographical locations in Argentina and the United States, but it has only been isolated in Arizona. The aim of this study was the isolation and genetic characterization of R. massiliae from R. sanguineus ticks collected from dogs in Buenos Aires city, Argentina. In total, 49 R. sanguineus ticks were collected from 10 dogs and grouped into 10 pools of 4-5 specimens. With a PCR assay, which detects a fragment of the Rickettsia genus-specific 23S-5S intergenic space, 1 pool of 5 ticks was found positive. Generated sequences exhibited 100% identity with R. massiliae . A new isolate, named CABA, was obtained from this pool by inoculating it into monolayers of Vero cells. Genotypic characteristics were determined, and results showed that fragments of the 23S-5S intergenic space, ompA, ompB, gltA, htrA, and sca1 genes had great similarity with R. massiliae strain Bar29 (Spain). Although few human cases have been confirmed for this pathogen, its circulation in urban areas is of great importance to public health. This isolation improves knowledge of the circulating pathogen and could improve future diagnostic processes as it allows the production of more specific antigens for serological testing.

  9. Anaplasma phagocytophilum and Rickettsia spp. infections in hard ticks (Ixodes ricinus) in the city of Hanover (Germany): revisited.

    Science.gov (United States)

    Tappe, Julia; Strube, Christina

    2013-09-01

    The present study aimed to determine the prevalence of Rickettsiales (A. phagocytophilum and Rickettsia spp.) in 2100 I. ricinus ticks collected at 10 different sampling sites every month during the tick season 2010 in the city of Hanover, northern Germany. At the same time, the results served as a fifth-year-follow-up study to monitor whether changes or stagnation of tick infection rates - possibly due to climate change--were obvious or not. To detect infections with A. phagocytophilum and/or Rickettsia spp., tick samples were analysed by quantitative real-time PCR. Differentiation of Rickettsia species was accomplished using real-time pyrosequencing technology. Overall, 4.5% (94/2100) of the collected ticks were tested positive for A. phagocytophilum and 26.2% (551/2100) were positive for Rickettsia spp. infections. Species differentiation of Rickettsia-positive ticks via real-time pyrosequencing was possible in 48.6% (268/551) of samples, which were all identified as R. helvetica. Coinfections with both pathogens were found in 1.0% (20/2100) of ticks. Statistically significant seasonal fluctuations between sampling months as well as local differences between sampling sites were detected for Rickettsia spp. infection rates. For A. phagocytophilum infections, only significant seasonal variations were found. When comparing infection rates of Hanoverian ticks in 2010 to those in 2005, infection rates of A. phagocytophilum-infected nymphs increased statistically significant (P=0.008, power: 0.762) from 2.3% in 2005 (Schicht et al., 2011) to 4.5% in 2010. Rickettsia spp. infections in female ticks decreased significantly (P=0.049, power: 0.491) from 41.8% in 2005 (Schicht et al., 2012) to 32.4% in 2010. Comparison of the remaining tick stages showed no statistically significant differences.

  10. por valores

    Directory of Open Access Journals (Sweden)

    Jazmín Díaz-Barrios

    2005-01-01

    Full Text Available La era actual se caracteriza por una búsqueda de la identidad del hombre, donde el pivote del cambio organizacional es el individuo; cambiar en este entorno depende, en gran medida, de los valores que imperen en la cultura de la organización. Este trabajo documental intenta identificar aquellos valores, condición sine-qua-non, para el logro de los objetivos de cambio y analizarlos a fin de determinar sus indicadores, con el objeto de presentar una herramienta a las organizaciones que les facilite adaptarse a los nuevos tiempos. Se encontró que los valores: Delegación, Comunicación, Colaboración, Participación y Aprendizaje, son esenciales en los cambios integrales de esta era. Se determinaron 20 indicadores de su presencia. Se concluye que con esta información cada ente puede elaborar instrumentos que le permitan saber si los valores requeridos están presentes y en caso contrario tomar decisiones que alineen a la organización alrededor de los valores humanistas planteados, incrementando así las posibilidades de éxito en el proceso de cambio y por ende, las posibilidades de supervivencia en esta nueva época.

  11. Prevalence of Rickettsiales (Anaplasma phagocytophilum and Rickettsia spp.) in hard ticks (Ixodes ricinus) in the city of Hamburg, Germany.

    Science.gov (United States)

    May, Kathrin; Strube, Christina

    2014-06-01

    To narrow the gap of missing knowledge on Rickettsia spp. and Anaplasma phagocytophilum infections in ticks in northwestern Germany and, at the same time, to provide first prevalence data on these pathogens in the city of Hamburg, a total of 1,400 questing Ixodes ricinus ticks were collected at ten different public green areas from April until October 2011. Ticks were examined using probe-based quantitative real-time PCR. A percentage of 3.6% (51/1,400) ticks were tested positive for A. phagocytophilum infections divided into 2.1% (3/141) adults [1.7% (1/60) females and 2.5% (2/81) males] and 3.8% (48/1,259) nymphs. The percentage of infected ticks per sampling site varied statistically significantly from 0.7% (1/140) to 12.1% (17/140), whereas between sampling months, no statistically significant differences were observed (2.0-6.5%, 4-13/140). The overall Rickettsia spp. infection rate was 52.5% (735/1,400). In adult ticks, Rickettsia spp. infection rate was 56% (79/141) divided into 61.7% (37/60) infected females and 51.9% (42/81) infected males. Nymphs showed an infection rate of 52.1% (656/1,259). In contrast to A. phagocytophilum infections, no statistically significant differences in Rickettsia spp. infection rates among sampling sites (44.3-63.6%, 62-89/140) were observed, whereas seasonal variations were obvious: the percentage of Rickettsia-positive ticks was significantly lower in April (36.5%, 73/200) and May (29.5%, 59/200) compared to the summer and fall months (55.0-64.5%, 110-129/200). Rickettsia species differentiation via real-time pyrosequencing revealed Rickettsia helvetica as the only occurring species. Co-infections with both Rickettsia spp. and A. phagocytophilum were detected in 2.0% (28/1,400) of the ticks. The present study revealed that in the city of Hamburg, the tick infection rate with A. phagocytophilum is comparable with other German data, whereas the Rickettsia spp. infection rate of 52.5% is by far the highest prevalence detected in

  12. Rickettsiae in arthropods collected from the North African Hedgehog (Atelerix algirus) and the desert hedgehog (Paraechinus aethiopicus) in Algeria.

    Science.gov (United States)

    Khaldi, Mourad; Socolovschi, Cristina; Benyettou, Meryam; Barech, Ghania; Biche, Mohamed; Kernif, Tahar; Raoult, Didier; Parola, Philippe

    2012-03-01

    Hedgehogs have become a popular pet despite their potential role in zoonotic disease transmission. We conducted an entomological study in a mountainous region of northeast Algeria in which we collected 387 fleas (Archeopsylla erinacei) and 342 ticks (Rhipicephalus sanguineus and Haemaphysalis erinacei) from Paraechinus aethiopicus and Atelerix algirus hedgehogs. Of the hedgehogs sampled, 77.7% and 91% were infested with fleas and ticks, respectively. Significantly more ticks and fleas were collected from A. algirus than from P. aethiopicus. Rickettsia felis was detected in 95.5% of fleas and R. massiliae was detected in 6.25% of Rh. sanguineus ticks by molecular tools. A new Rickettsia species of the spotted fever group was detected in 11.25% of Rh. sanguineus and in 77% of H. erinacei ticks. Overall, we show that hedgehogs can act as hosts for ectoparasites infected with several rickettsial agents. These data justify a more detailed investigation of animal reservoirs for Rickettsiae. PMID:22222114

  13. Detection of Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in hard ticks (Acari, Ixodidae) parasitizing bats in Poland.

    Science.gov (United States)

    Piksa, Krzysztof; Stańczak, Joanna; Biernat, Beata; Górz, Andrzej; Nowak-Chmura, Magdalena; Siuda, Krzysztof

    2016-04-01

    A total of 491 Ixodes vespertilionis and 8 Ixodes ricinus collected from bats and cave walls in southern Poland between 2010 and 2012 were examined by the polymerase chain reaction for tick-transmitted pathogens. PCR analysis for Borrelia burgdorferi s.l., Rickettsia spp., and Anaplasma phagocytophilum yielded negative results for all I. vespertilionis. DNA of Rickettsia helvetica was detected in three specimens of I. ricinus attached to Rhinolophus hipposideros or Myotis myotis, while Borrelia garinii was found in one tick parasitizing Myotis daubentonii. These pathogens were recorded for the first time in hard ticks that parasitized bats. PMID:26833325

  14. Differences in intracellular fate of two spotted fever group Rickettsia in macrophage-like cells

    Directory of Open Access Journals (Sweden)

    Pedro Curto

    2016-07-01

    Full Text Available Spotted fever group (SFG rickettsiae are recognized as important agents of human tick-borne diseases worldwide, such as Mediterranean spotted fever (R. conorii and Rocky Mountain spotted fever (R. rickettsii. Recent studies in several animal models have provided evidence of non-endothelial parasitism by pathogenic SFG Rickettsia species, suggesting that the interaction of rickettsiae with cells other than the endothelium may play an important role in pathogenesis of rickettsial diseases. These studies raise the hypothesis that the role of macrophages in rickettsial pathogenesis may have been underappreciated. Herein, we evaluated the ability of two SFG rickettsial species, R. conorii (a recognized human pathogen and R. montanensis (a non-virulent member of SFG to proliferate in THP-1 macrophage-like cells, or within non-phagocytic cell lines. Our results demonstrate that R. conorii was able to survive and proliferate in both phagocytic and epithelial cells in vitro. In contrast, R. montanensis was able to grow in non-phagocytic cells, but was drastically compromised in the ability to proliferate within both undifferentiated and PMA-differentiated THP-1 cells. Interestingly, association assays revealed that R. montanensis was defective in binding to THP-1-derived macrophages; however, the invasion of the bacteria that are able to adhere did not appear to be affected. We have also demonstrated that R. montanensis which entered into THP-1-derived macrophages were rapidly destroyed and partially co-localized with LAMP-2 and cathepsin D, two markers of lysosomal compartments. In contrast, R. conorii was present as intact bacteria and free in the cytoplasm in both cell types. These findings suggest that a phenotypic difference between a non-pathogenic and a pathogenic SFG member lies in their respective ability to proliferate in macrophage-like cells, and may provide an explanation as to why certain SFG rickettsial species are not associated with

  15. Anti-Rickettsia spp. antibodies in free-ranging and captive capybaras from southern Brazil

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    Fernanda S. Fortes

    2011-11-01

    Full Text Available Capybaras (Hydrochaeris hydrochaeris are among the main hosts of Amblyomma spp. ticks, which is able to transmit Rickettsia species to human beings and animals. Since they are often infested with potential vector ticks, capybaras may be used as sentinels for rickettsiosis, such as the Brazilian Spotted Fever. The aim of the present study was to determine the prevalence of antibodies against Rickettsia spp. using the indirect immunofluorescence assay (IFA in 21 free-ranging and 10 captive animals from the Zoological Park of the 'Bela Vista Biological Sanctuary' (BVBS, Itaipu Binational, Foz do Iguaçu, Southern Brazil. Antigens of six rickettsial species already identified in Brazil (Rickettsia rickettsii, R. parkeri, R. bellii, R. rhipicephali, R. amblyommii and R. felis were used for IFA. Ticks from each capybara were collected for posterior taxonomic identification. A total of 19 (61.3% samples reacted to at least one of tested species. Seropositivity was found in 14 (45.2%, 12 (38.7%, 5 (16.1%, 4 (12.9%, 3 (9.7% and 3 (9.7% animals for R. rickettsii, R. bellii, R. parkeri, R. amblyommii, R. felis and R. rhipicephali, respectively. Two captive capybaras presented suggestive titers of R. rickettsii infection and one sample showed homologous reaction to R. parkeri. Only one free-ranging capybara presented evidence R. bellii infection. Ticks collected on capybaras were identified as Amblyomma dubitatum e Amblyomma sp. Results evidenced the rickettsial circulation in the area, suggesting a potential role of capybaras on bacterial life cycle.

  16. Notes from the Field: Rickettsia parkeri Rickettsiosis - Georgia, 2012-2014.

    Science.gov (United States)

    Straily, Anne; Feldpausch, Amanda; Ulbrich, Carl; Schell, Kiersten; Casillas, Shannon; Zaki, Sherif R; Denison, Amy M; Condit, Marah; Gabel, Julie; Paddock, Christopher D

    2016-01-01

    During 2012-2014, five cases of Rickettsia parkeri rickettsiosis were identified by a single urgent care practice in Georgia, located approximately 40 miles southwest of Atlanta. Symptom onset occurred during June-October, and all patients had a known tick bite. Patients ranged in age from 27 to 72 years (median = 53 years), and all were male. The most commonly reported initial signs were erythema (n = 3) and swelling (n = 2) at the site of the bite. Two patients reported fever and a third patient reported a rash and lymphadenopathy without fever. Other symptoms included myalgia (n = 3), chills (n = 3), fatigue (n = 2), arthralgia (n = 2), and headache (n = 2). Eschar biopsy specimens were collected from each patient using a 4-mm or 5-mm punch and placed in 10% neutral buffered formalin or sterile saline. These specimens were tested by immunohistochemical (IHC) stains, quantitative polymerase chain reaction (qPCR) assays, or cell culture isolation to determine if there was evidence of infection with a Rickettsia species (1). IHC evidence of spotted fever group rickettsiae was found in the eschar biopsy specimens in all five cases. In four cases, the biopsy specimens were also positive for R. parkeri by qPCR. The fifth case (specimen positive only by IHC testing) was considered a probable R. parkeri case based on clinical signs and symptoms. R. parkeri was grown in cell culture from one specimen from which isolation was attempted. All patients were treated with oral doxycycline (100 mg twice daily) for a minimum of 10 days, and all recovered. PMID:27442517

  17. Genomic and comparative genomic analyses of Rickettsia heilongjiangensis provide insight into its evolution and pathogenesis.

    Science.gov (United States)

    Duan, Changsong; Xiong, Xiaolu; Qi, Yong; Gong, Wenping; Jiao, Jun; Wen, Bohai

    2014-08-01

    Rickettsia heilongjiangensis, the causative agent of far eastern spotted fever, is an obligate intracellular gram-negative bacterium that belongs to the spotted fever group rickettsiae. To understand the evolution and pathogenesis of R. heilongjiangensis, we analyzed its genome and compared it with other rickettsial genomes available in GenBank. The R. heilongjiangensis chromosome contains 1333 genes, including 1297 protein coding genes and 36 RNA coding genes. The genome also contains 121 pseudogenes, 54 insertion sequences, and 39 tandem repeats. Sixteen genes encoding the major components of the type IV secretion systems were identified in the R. heilongjiangensis genome. In total, 37 β-barrel outer membrane proteins were predicted in the genome, eight of which have been previously confirmed to be outer membrane proteins. In addition, 266 potential virulence factor genes, seven partially deleted antibiotic resistance genes, and a genomic island were identified in the genome. The codon usage in the genome is compatible with its low GC content, and the amino acid usage shows apparent bias. A comparative genomic analysis showed that R. heilongjiangensis and R. japonica share one unique fragment that may be a target sequence for a diagnostic assay. The orthologs of 37 genes of R. heilongjiangensis were found in pathogenic R. rickettsii str. Sheila Smith but not in non-pathogenic R. rickettsii str. Iowa, which may explain why R. heilongjiangensis is pathogenic. Pan-genome analysis showed that R. heilongjiangensis and 42 other rickettsiae strains share 693 core genes with a pan-genome size of 4837 genes. The pan-genome-based phylogeny showed that R. heilongjiangensis was closely related to R. japonica.

  18. 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

  19. Which Way In? The RalF Arf-GEF Orchestrates Rickettsia Host Cell Invasion.

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    Kristen E Rennoll-Bankert

    2015-08-01

    Full Text Available Bacterial Sec7-domain-containing proteins (RalF are known only from species of Legionella and Rickettsia, which have facultative and obligate intracellular lifestyles, respectively. L. pneumophila RalF, a type IV secretion system (T4SS effector, is a guanine nucleotide exchange factor (GEF of ADP-ribosylation factors (Arfs, activating and recruiting host Arf1 to the Legionella-containing vacuole. In contrast, previous in vitro studies showed R. prowazekii (Typhus Group RalF is a functional Arf-GEF that localizes to the host plasma membrane and interacts with the actin cytoskeleton via a unique C-terminal domain. As RalF is differentially encoded across Rickettsia species (e.g., pseudogenized in all Spotted Fever Group species, it may function in lineage-specific biology and pathogenicity. Herein, we demonstrate RalF of R. typhi (Typhus Group interacts with the Rickettsia T4SS coupling protein (RvhD4 via its proximal C-terminal sequence. RalF is expressed early during infection, with its inactivation via antibody blocking significantly reducing R. typhi host cell invasion. For R. typhi and R. felis (Transitional Group, RalF ectopic expression revealed subcellular localization with the host plasma membrane and actin cytoskeleton. Remarkably, R. bellii (Ancestral Group RalF showed perinuclear localization reminiscent of ectopically expressed Legionella RalF, for which it shares several structural features. For R. typhi, RalF co-localization with Arf6 and PI(4,5P2 at entry foci on the host plasma membrane was determined to be critical for invasion. Thus, we propose recruitment of PI(4,5P2 at entry foci, mediated by RalF activation of Arf6, initiates actin remodeling and ultimately facilitates bacterial invasion. Collectively, our characterization of RalF as an invasin suggests that, despite carrying a similar Arf-GEF unknown from other bacteria, different intracellular lifestyles across Rickettsia and Legionella species have driven divergent roles

  20. Which Way In? The RalF Arf-GEF Orchestrates Rickettsia Host Cell Invasion.

    Science.gov (United States)

    Rennoll-Bankert, Kristen E; Rahman, M Sayeedur; Gillespie, Joseph J; Guillotte, Mark L; Kaur, Simran J; Lehman, Stephanie S; Beier-Sexton, Magda; Azad, Abdu F

    2015-08-01

    Bacterial Sec7-domain-containing proteins (RalF) are known only from species of Legionella and Rickettsia, which have facultative and obligate intracellular lifestyles, respectively. L. pneumophila RalF, a type IV secretion system (T4SS) effector, is a guanine nucleotide exchange factor (GEF) of ADP-ribosylation factors (Arfs), activating and recruiting host Arf1 to the Legionella-containing vacuole. In contrast, previous in vitro studies showed R. prowazekii (Typhus Group) RalF is a functional Arf-GEF that localizes to the host plasma membrane and interacts with the actin cytoskeleton via a unique C-terminal domain. As RalF is differentially encoded across Rickettsia species (e.g., pseudogenized in all Spotted Fever Group species), it may function in lineage-specific biology and pathogenicity. Herein, we demonstrate RalF of R. typhi (Typhus Group) interacts with the Rickettsia T4SS coupling protein (RvhD4) via its proximal C-terminal sequence. RalF is expressed early during infection, with its inactivation via antibody blocking significantly reducing R. typhi host cell invasion. For R. typhi and R. felis (Transitional Group), RalF ectopic expression revealed subcellular localization with the host plasma membrane and actin cytoskeleton. Remarkably, R. bellii (Ancestral Group) RalF showed perinuclear localization reminiscent of ectopically expressed Legionella RalF, for which it shares several structural features. For R. typhi, RalF co-localization with Arf6 and PI(4,5)P2 at entry foci on the host plasma membrane was determined to be critical for invasion. Thus, we propose recruitment of PI(4,5)P2 at entry foci, mediated by RalF activation of Arf6, initiates actin remodeling and ultimately facilitates bacterial invasion. Collectively, our characterization of RalF as an invasin suggests that, despite carrying a similar Arf-GEF unknown from other bacteria, different intracellular lifestyles across Rickettsia and Legionella species have driven divergent roles for Ral

  1. Antibodies against spotted fever group Rickettsia sp., in horses of the colombian Orinoquia

    OpenAIRE

    Diego A. Riveros-Pinilla; Leidy Acevedo G; Andrés F. Londoño; Agustín Góngora O

    2015-01-01

    ABSTRACT Objective. It was determined the presence of antibodies against Rickettsia sp. of the spotted fever group, in horses of 8 municipalities of the Colombian Orinoquia. Matherials and methods. A cross-sectional study was conducted on 246 sera from apparently healthy horses and processed by the indirect immunofluorescence test (IFI). Results. General seropositivity was (2.85%; 7/246), while by municipalities the results were, Arauca (9.1%; 2/22), Saravena (5.6%; 1/18), San José del Guav...

  2. Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCATÁN AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

    OpenAIRE

    PENICHE-LARA, Gaspar; Dzul-Rosado, Karla; PÉREZ-OSORIO, Carlos; Zavala-Castro, Jorge

    2015-01-01

    Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chai...

  3. Multispacer Typing (MST) of Spotted Fever Group Rickettsiae Isolated from Humans and Rats in Chengmai County, Hainan Province, China.

    Science.gov (United States)

    Cheng, Xueqin; Jin, Yuming; Lao, Shijun; Huang, Changhe; Huang, Fang; Jia, Pengben; Zhang, Lijuan

    2014-09-01

    Spotted fever caused by spotted fever group rickettsiae (SFGR) is found throughout China. During 2007-2008, 28 human SFGR isolates and 34 rat SFGR isolates including 15 isolates from Rattus fulvescens, 5 isolates from R. edwardsi, 7 isolates from Callosciurus erythraeus roberti and 7 isolates from Dremomys rufigenis) were obtained from L929 cell culture. Previous research indicated that the 62 strains of SFGR mentioned above shared not only the same serophenotype but also 100% of identity sequences of 16S rRNA, gltA, ompA, groEL and 17KD, which enabled us to apply multispacer typing (MST) to the 62 SFGR isolates in the study. Six primer pairs, which were used for typing of Rickettsia rickettsii and Rickettsia conorii, were chosen, and the results exhibited greater nucleotide polymorphisms among the 62 isolates tested. A total of 48 distinct genotypes were identified. The dominant genotype, represented by h3 isolates, accounted for 21.7% (13/60) of the isolates tested, and the remaining 47 genotypes were all unique. Phylogenetic analysis showed that all the 48 genotypes could be classified in the same clade, while the genetically related strain, R. heilongjiangensis, was close but not the same as the cluster. We concluded that the genetically diverse of spotted fever group rickettsiae strains are endemic in Chengmai County, Hainan Province, China. PMID:25324688

  4. Prevalence of Rickettsia species in Dermacentor variabilis ticks from Ontario, Canada.

    Science.gov (United States)

    Wood, Heidi; Dillon, Liz; Patel, Samir N; Ralevski, Filip

    2016-07-01

    Relatively little is known about the prevalence of rickettsial species in Dermacentor ticks in eastern Canada. In this study, Dermacentor ticks from the province of Ontario, Canada, were tested for the presence of spotted fever group rickettsial (SFGR) species, Coxiella burnetii and Francisella tularensis. Rickettsia rickettsii was not detected in any ticks tested, but R. montanensis was detected at a prevalence of 2.2% in D. variabilis (17/778). Two other SFGR species, R. parkeri and Candidatus R. andeanae, were detected individually in 2 Amblyomma maculatum ticks. Rickettsia peacockii, a non-pathogenic endosymbiont, was detected in two D. andersonii ticks. Given the highly abundant nature of D. variabilis, surveillance for human pathogens in this species of tick has important public health implications, but the lack of detection of known human pathogens indicates a low risk of infection via this tick species in Ontario. However, the detection of R. parkeri in an adventive A. maculatum tick indicates that health care providers should be aware of the possibility of spotted fever rickettsioses in individuals with a history of travel outside of Ontario and symptoms compatible with a spotted fever rickettsiosis. Coxiella burnetii and Francisella tularensis, human pathogens also potentially transmitted by D. variabilis, were not detected in a subset of the ticks. PMID:27318438

  5. Seroprevalence of antibodies to Rickettsia typhi in the Waikato region of New Zealand.

    Science.gov (United States)

    Lim, M Y; Weinstein, P; Bell, A; Hambling, T; Tompkins, D M; Slaney, D

    2016-08-01

    The first reported New Zealand-acquired case of murine typhus occurred near Auckland in 1989. Since then, 72 locally acquired cases have been recorded from northern New Zealand. By 2008, on the basis of the timing and distribution of cases, it appeared that murine typhus was escalating and spreading southwards. To explore the presence of Rickettsia typhi in the Waikato region, we conducted a seroprevalence study, using indirect immunofluorescence, Western blot, and cross-adsorption assays of blood donor samples. Of 950 human sera from Waikato, 12 (1·3%) had R. typhi antibodies. The seroprevalence for R. typhi was slightly higher in northern Waikato (1·4%) compared to the south (1·2%; no significant difference, χ 2 P = 0·768 at P < 0·05). Our results extend the reported southern range of R. typhi by 140 km and indicate it is endemic in Waikato. Evidence of past Rickettsia felis infections was also detected in six sera. Globally, R. felis is an emerging disease of concern and this pathogen should also be considered when locally acquired rickettsiosis is suspected. If public health interventions are to be implemented to reduce the risk of rickettsioses as a significant public health problem, improvements in rickettsial diagnostics and surveillance will be necessary. PMID:27040715

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

    Science.gov (United States)

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

    2015-12-01

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

  7. Detection of a novel Rickettsia sp. in soft ticks (Acari: Argasidae) in Algeria.

    Science.gov (United States)

    Lafri, Ismail; Leulmi, Hamza; Baziz-Neffah, Fadhila; Lalout, Reda; Mohamed, Chergui; Mohamed, Karakallah; Parola, Philippe; Bitam, Idir

    2015-01-01

    Argasid ticks are vectors of viral and bacterial agents that can infect humans and animals. In Africa, relapsing fever borreliae are neglected arthropod-borne pathogens that cause mild to deadly septicemia and miscarriage. It would be incredibly beneficial to be able to simultaneous detect and identify other pathogens transmitted by Argasid ticks. From 2012 to 2014, we conducted field surveys in 4 distinct areas of Algeria. We investigated the occurrence of soft ticks in rodent burrows and yellow-legged gull (Larus michahellis) nests in 10 study sites and collected 154 soft ticks. Molecular identification revealed the occurrence of two different soft tick genera and five species, including Carios capensis in yellow-legged gull nests and Ornithodoros occidentalis, Ornithodoros rupestris, Ornithodoros sonrai, Ornithodoros erraticus in rodent burrows. Rickettsial DNA was detected in 41/154, corresponding to a global detection rate of 26.6%. Sequences of the citrate synthase (gltA) gene suggest that this agent is a novel spotted fever group Rickettsia. For the first time in Algeria, we characterize a novel Rickettsia species by molecular means in soft ticks.

  8. 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.

  9. Antibodies against spotted fever group Rickettsia sp., in horses of the colombian Orinoquia

    Directory of Open Access Journals (Sweden)

    Diego A. Riveros-Pinilla

    2015-11-01

    Full Text Available Objective. It was determined the presence of antibodies against Rickettsia sp. of the spotted fever group, in horses of 8 municipalities of the Colombian Orinoquia. Matherials and methods. A cross-sectional study was conducted on 246 sera from apparently healthy horses and processed by the indirect immunofluorescence test (IFI. Results. General seropositivity was (2.85%; 7/246, while by municipalities the results were, Arauca (9.1%; 2/22, Saravena (5.6%; 1/18, San José del Guaviare (4.9%; 2/41, San Martín (3.8%; 1/26, Yopal (1.9%; 1/52. It was not identified the presence of antibodies in Puerto López (0/52, Puerto Gaitán (0/15 and Villavicencio (0/20. Four of the positive samples presented titles of 1:64, while the remaining 3 1:128. Conclusions. It shows the circulation of Rickettsia sp. of the Spotted Fever Group in horses in the region of the Colombian Orinoquia, suggesting the need for further studies to understand the ecoepidemiology of municipalities with presence of seropositive.

  10. Proteome analysis and serological characterization of surface-exposed proteins of Rickettsia heilongjiangensis.

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    Yong Qi

    Full Text Available BACKGROUND: Rickettsia heilongjiangensis, the agent of Far-Eastern spotted fever (FESF, is an obligate intracellular bacterium. The surface-exposed proteins (SEPs of rickettsiae are involved in rickettsial adherence to and invasion of host cells, intracellular bacterial growth, and/or interaction with immune cells. They are also potential molecular candidates for the development of diagnostic reagents and vaccines against rickettsiosis. METHODS: R. heilongjiangensis SEPs were identified by biotin-streptavidin affinity purification and 2D electrophoreses coupled with ESI-MS/MS. Recombinant SEPs were probed with various sera to analyze their serological characteristics using a protein microarray and an enzyme-linked immune sorbent assay (ELISA. RESULTS: Twenty-five SEPs were identified, most of which were predicted to reside on the surface of R. heilongjiangensis cells. Bioinformatics analysis suggests that these proteins could be involved in bacterial pathogenesis. Eleven of the 25 SEPs were recognized as major seroreactive antigens by sera from R. heilongjiangensis-infected mice and FESF patients. Among the major seroreactive SEPs, microarray assays and/or ELISAs revealed that GroEL, OmpA-2, OmpB-3, PrsA, RplY, RpsB, SurA and YbgF had modest sensitivity and specificity for recognizing R. heilongjiangensis infection and/or spotted fever. CONCLUSIONS: Many of the SEPs identified herein have potentially important roles in R. heilongjiangensis pathogenicity. Some of them have potential as serodiagnostic antigens or as subunit vaccine antigens against the disease.

  11. 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.

  12. Molecular detection of Rickettsia aeschlimannii in Hyalomma spp. ticks from camels (Camelus dromedarius) in Nigeria, West Africa.

    Science.gov (United States)

    Kamani, J; Baneth, G; Apanaskevich, D A; Mumcuoglu, K Y; Harrus, S

    2015-06-01

    Several species of the spotted fever group rickettsiae have been identified as emerging pathogens throughout the world, including in Africa. In this study, 197 Hyalomma ticks (Ixodida: Ixodidae) collected from 51 camels (Camelus dromedarius) in Kano, northern Nigeria, were screened by amplification and sequencing of the citrate synthase (gltA), outer membrane protein A (ompA) and 17-kDa antigen gene fragments. Rickettsia sp. gltA fragments were detected in 43.3% (42/97) of the tick pools tested. Rickettsial ompA gene fragments (189 bp and 630 bp) were detected in 64.3% (n = 27) and 23.8% (n = 10) of the gltA-positive tick pools by real-time and conventional polymerase chain reaction (PCR), respectively. The amplicons were 99-100% identical to Rickettsia aeschlimannii TR/Orkun-H and R. aeschlimannii strain EgyRickHimp-El-Arish in GenBank. Furthermore, 17-kDa antigen gene fragments of 214 bp and 265 bp were detected in 59.5% (n = 25) and 38.1% (n = 16), respectively, of tick pools, and sequences were identical to one another and 99-100% identical to those of the R. aeschlimannii strain Ibadan A1 in GenBank. None of the Hyalomma impressum ticks collected were positive for Rickettsia sp. DNA. Rickettsia sp. gltA fragments (133 bp) were detected in 18.8% of camel blood samples, but all samples were negative for the other genes targeted. This is the first report to describe the molecular detection of R. aeschlimannii in Hyalomma spp. ticks from camels in Nigeria.

  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. Prevalence of Rickettsia raoultii in Dermacentor marginatus ticks from wild boars in France%法国野猪中Rickettsia raoultii的流行

    Institute of Scientific and Technical Information of China (English)

    曲芬; Jean Luc Llabers; Oleg Mediannikov; Jean-Marc Rolain

    2010-01-01

    目的 调查和鉴定法国野猪身上Rickettsia raoultii的流行情况以及野猪作为贮存宿主所起的作用.方法 收集法国2007年9月到11月的野猪身上的边缘革蜱163只.应用柠檬酸合成酶基因和外膜蛋白基因进行实时定量PCR、普通PCR技术及序列分析方法检测立克次体.结果 113只(69.3%)边缘革蜱立克次检测阳性.进一步鉴定为斑点热的两类病原,其中R.raoultii占57.5%(存在于65只蜱中)和R.slovaca占42.5%(存在于48只蜱中).结论 证明R.raoultii是野猪身上边缘革蜱的主要病原,边缘革蜱中感染率较高.应警惕野猪对立克次体的传播作用.

  15. Preliminary research on the distribution and transmission efficiency of Rickettsia, an endosymbiont of whitefly Bemisia tabaci%烟粉虱内共生菌 Rickettsia 在植物体内的分布及转移效率初探

    Institute of Scientific and Technical Information of China (English)

    安璇; 李翌菡; 李绍建; 郭长飞; 任顺祥; 邱宝利

    2015-01-01

    【目的】检测 Q 型烟粉虱 Bemisia tabaci (Gennadius)体内 Rickettsia 的感染情况,研究分析Rickettsia 共生菌经烟粉虱传入豇豆植物后的分布、转移效率等。【方法】以 Q 型烟粉虱为实验材料,利用常规 PCR 及荧光原位杂交技术(FISH),检测了烟粉虱体内 Rickettsia 的感染率,以及 Rickettsia 传入豇豆植物体内后的存留情况。【结果】 Q 型烟粉虱可以通过取食将 Rickettsia 传至豇豆植株内;接虫数量与 Rickettsia传入效率及其在取食部位相邻的下部叶片中检测到的起始时间呈负相关;Rickettsia 经烟粉虱取食传入豇豆叶片后,集中分布在叶片的韧皮部筛管中;基于16S rRNA 的系统发育分析结果表明,Q 型烟粉虱体内的Rickettsia 与经取食传入豇豆叶片的 Rickettsia 高度同源。【结论】 Rickettsia 可以通过烟粉虱的取食传入植物体内,并且可以在相邻叶片之间转移传播,Rickettsia 在由寄主昆虫向植株传播过程中高度保守。%Objectives] To detect the infection of Bemisia tabaci by Rickettsia, and the distribution and dissemination of Rickettsia after its transmission to cowpea leaves through whitefly feeding. [Methods] Infection of the B. tabaci Q biotype by Rickettsia, and its persistence in cowpea plants, were detected by PCR and fluoresent in situ hybridization (FISH). [Results] The distribution of Rickettsia was limited to the phloem vessels of cowpea leaves, Rickettsia could move along the vessels between different leaves, and its efficiency of dissemination was highly related to the initial population size of Rickettsia-positive B. tabaci individuals that fed on the cowpea leaves. Phylogenetic analysis based on 16S rRNA variation showed that Rickettsia in cowpea plants and whiteflies was 100% identical. [Conclusion] Rickettsia can be horizontally transmitted to cowpea plants through the feeding of the B. tabaci Q biotype and little genetic variation

  16. Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCATÁN AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

    Directory of Open Access Journals (Sweden)

    Gaspar PENICHE-LARA

    2015-04-01

    Full Text Available Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study’s results contributed to a better knowledge of Rickettsia epidemiology in Yucatán.

  17. Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCATÁN AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

    Science.gov (United States)

    PENICHE-LARA, Gaspar; DZUL-ROSADO, Karla; PÉREZ-OSORIO, Carlos; ZAVALA-CASTRO, Jorge

    2015-01-01

    Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucatán are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucatán. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucatán using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study’s results contributed to a better knowledge of Rickettsia epidemiology in Yucatán. PMID:25923891

  18. High prevalence of Rickettsia africae variants in Amblyomma variegatum ticks from domestic mammals in rural western Kenya: implications for human health.

    Science.gov (United States)

    Maina, Alice N; Jiang, Ju; Omulo, Sylvia A; Cutler, Sally J; Ade, Fredrick; Ogola, Eric; Feikin, Daniel R; Njenga, M Kariuki; Cleaveland, Sarah; Mpoke, Solomon; Ng'ang'a, Zipporah; Breiman, Robert F; Knobel, Darryn L; Richards, Allen L

    2014-10-01

    Tick-borne spotted fever group (SFG) rickettsioses are emerging human diseases caused by obligate intracellular Gram-negative bacteria of the genus Rickettsia. Despite being important causes of systemic febrile illnesses in travelers returning from sub-Saharan Africa, little is known about the reservoir hosts of these pathogens. We conducted surveys for rickettsiae in domestic animals and ticks in a rural setting in western Kenya. Of the 100 serum specimens tested from each species of domestic ruminant 43% of goats, 23% of sheep, and 1% of cattle had immunoglobulin G (IgG) antibodies to the SFG rickettsiae. None of these sera were positive for IgG against typhus group rickettsiae. We detected Rickettsia africae-genotype DNA in 92.6% of adult Amblyomma variegatum ticks collected from domestic ruminants, but found no evidence of the pathogen in blood specimens from cattle, goats, or sheep. Sequencing of a subset of 21 rickettsia-positive ticks revealed R. africae variants in 95.2% (20/21) of ticks tested. Our findings show a high prevalence of R. africae variants in A. variegatum ticks in western Kenya, which may represent a low disease risk for humans. This may provide a possible explanation for the lack of African tick-bite fever cases among febrile patients in Kenya.

  19. First detections of Rickettsia helvetica and R. monacensis in ectoparasitic mites (Laelapidae and Trombiculidae) infesting rodents in south-western Slovakia.

    Science.gov (United States)

    Miťková, Katarína; Berthová, Lenka; Kalúz, Stanislav; Kazimírová, Mária; Burdová, Lenka; Kocianová, Elena

    2015-07-01

    Information on circulation of rickettsiae between small mammals and their ectoparasitic mites is scarce. In this study, we investigated infestation rates of rodents with mites in some areas of SW Slovakia and the role of mites as possible vectors of pathogenic rickettsiae. A total of 615 rodents of five species were caught during 2010-2012. All individuals were examined for ectoparasites which resulted in 2821 mites belonging to three species of Laelapidae and six species of Trombiculidae. The most common Laelapidae species was Laelaps agilis (81.25 %), followed by Haemogamasus nidi, and Eulaelaps stabularis. Hirsutiella zachvatkini (16.52 %) was the dominant species of the family Trombiculidae. DNA extracted from rodent blood and ectoparasitic mites was examined for the presence of rickettsiae by PCR. By pooling mites, 345 pool samples were created, of which 112 (32.46 %) were found to be positive for the rickettsial DNA. From 487 examined rodent blood samples, rickettsial DNA was found in 46 (9.44 %). Sequencing DNA from the positive blood samples and mites revealed the identity of Rickettsia helvetica and Rickettsia monacensis. The results of the study suggest that ectoparasitic mites may be reservoirs as well as vectors of some pathogenic rickettsiae.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. 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.

  2. Progress in research of Rickettsia felis%猫立克次体研究进展

    Institute of Scientific and Technical Information of China (English)

    刘杨; 杨雨; 陈萍; 赵锋; 钟玮

    2015-01-01

    猫立克次体(Rickettsia felis)可以引起蚤传斑点热(Flea-Borne Spotted Fever,FBSF),主要传播媒介是猫蚤(Ctenocephalides felis).自上世纪90年代首次发现以来,已被证实分布于地球上除南极以外的各大洲.本文对猫立克次体的传播媒介、检测方法以及基因组学研究进展进行了综述,并讨论了在全球气候变化的背景下,开展猫立克次体研究的重要意义.

  3. A confirmed case of Rickettsia parkeri infection in a traveler from Uruguay.

    Science.gov (United States)

    Portillo, Aránzazu; García-García, Concepción; Sanz, M Mercedes; Santibáñez, Sonia; Venzal, José M; Oteo, José A

    2013-12-01

    The first confirmed case of Rickettsia parkeri infection in Uruguay is reported. To date, in South America, molecularly confirmed cases of human infection have been found in Argentina and probably, Brazil. Our patient returned to Spain after a 7-day trip to Colonia Suiza (Southwestern Uruguay). He presented fever (39°C), chills, and two eschars (tache noire-like) surrounded by an indurated, erythematous halo on the inner side of the left ankle besides a maculopapular rash on the legs. After treatment with doxycycline for 7 days, he fully recovered. R. parkeri infection was diagnosed by molecular-based detection of the microorganism in a swab specimen of the eschar. Diagnosis was supported by seroconversion between acute- and convalescent-phase sera specimens.

  4. Plasmids of the pRM/pRF family occur in diverse Rickettsia species.

    Science.gov (United States)

    Baldridge, Gerald D; Burkhardt, Nicole Y; Felsheim, Roderick F; Kurtti, Timothy J; Munderloh, Ulrike G

    2008-02-01

    The recent discoveries of the pRF and pRM plasmids of Rickettsia felis and R. monacensis have contravened the long-held dogma that plasmids are not present in the bacterial genus Rickettsia (Rickettsiales; Rickettsiaceae). We report the existence of plasmids in R. helvetica, R. peacockii, R. amblyommii, and R. massiliae isolates from ixodid ticks and in an R. hoogstraalii isolate from an argasid tick. R. peacockii and four isolates of R. amblyommii from widely separated geographic locations contained plasmids that comigrated with pRM during pulsed-field gel electrophoresis and larger plasmids with mobilities similar to that of pRF. The R. peacockii plasmids were lost during long-term serial passage in cultured cells. R. montanensis did not contain a plasmid. Southern blots showed that sequences similar to those of a DnaA-like replication initiator protein, a small heat shock protein 2, and the Sca12 cell surface antigen genes on pRM and pRF were present on all of the plasmids except for that of R. massiliae, which lacked the heat shock gene and was the smallest of the plasmids. The R. hoogstraalii plasmid was most similar to pRM and contained apparent homologs of proline/betaine transporter and SpoT stringent response genes on pRM and pRF that were absent from the other plasmids. The R. hoogstraalii, R. helvetica, and R. amblyommii plasmids contained homologs of a pRM-carried gene similar to a Nitrobacter sp. helicase RecD/TraA gene, but none of the plasmids hybridized with a probe derived from a pRM-encoded gene similar to a Burkholderia sp. transposon resolvase gene.

  5. Genomic diversification in strains of Rickettsia felis Isolated from different arthropods.

    Science.gov (United States)

    Gillespie, Joseph J; Driscoll, Timothy P; Verhoeve, Victoria I; Utsuki, Tadanobu; Husseneder, Claudia; Chouljenko, Vladimir N; Azad, Abdu F; Macaluso, Kevin R

    2015-01-01

    Rickettsia felis (Alphaproteobacteria: Rickettsiales) is the causative agent of an emerging flea-borne rickettsiosis with worldwide occurrence. Originally described from the cat flea, Ctenocephalides felis, recent reports have identified R. felis from other flea species, as well as other insects and ticks. This diverse host range for R. felis may indicate an underlying genetic variability associated with host-specific strains. Accordingly, to determine a potential genetic basis for host specialization, we sequenced the genome of R. felis str. LSU-Lb, which is an obligate mutualist of the parthenogenic booklouse Liposcelis bostrychophila (Insecta: Psocoptera). We also sequenced the genome of R. felis str. LSU, the second genome sequence for cat flea-associated strains (cf. R. felis str. URRWXCal2), which are presumably facultative parasites of fleas. Phylogenomics analysis revealed R. felis str. LSU-Lb diverged from the flea-associated strains. Unexpectedly, R. felis str. LSU was found to be divergent from R. felis str. URRWXCal2, despite sharing similar hosts. Although all three R. felis genomes contain the pRF plasmid, R. felis str. LSU-Lb carries an additional unique plasmid, pLbaR (plasmid of L. bostrychophila associated Rickettsia), nearly half of which encodes a unique 23-gene integrative conjugative element. Remarkably, pLbaR also encodes a repeats-in-toxin-like type I secretion system and associated toxin, heretofore unknown from other Rickettsiales genomes, which likely originated from lateral gene transfer with another obligate intracellular parasite of arthropods, Cardinium (Bacteroidetes). Collectively, our study reveals unexpected genomic diversity across three R. felis strains and identifies several diversifying factors that differentiate facultative parasites of fleas from obligate mutualists of booklice. PMID:25477419

  6. Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild?

    Directory of Open Access Journals (Sweden)

    Cristina Socolovschi

    Full Text Available BACKGROUND: Rickettsia conorii conorii is the etiological agent of Mediterranean spotted fever, which is transmitted by the brown dog tick, Rhipicephalus sanguineus. The relationship between the Rickettsia and its tick vector are still poorly understood one century after the first description of this disease. METHODOLOGY/PRINCIPAL FINDINGS: An entomological survey was organized in Algeria to collect ticks from the houses of patients with spotted fever signs. Colonies of R. conorii conorii-infected and non-infected ticks were established under laboratory conditions. Gimenez staining and electron microscopy on the ovaries of infected ticks indicated heavy rickettsial infection. The transovarial transmission of R. conorii conorii in naturally infected Rh. sanguineus ticks was 100% at eleven generations, and the filial infection rate was up to 99% according to molecular analyses. No differences in life cycle duration were observed between infected and non-infected ticks held at 25°C, but the average weight of engorged females and eggs was significantly lower in infected ticks than in non-infected ticks. The eggs, larvae and unfed nymphs of infected and non-infected ticks could not tolerate low (4°C or high (37°C temperatures or long starvation periods. R. conorii conorii-infected engorged nymphs that were exposed to a low or high temperature for one month experienced higher mortality when they were transferred to 25°C than non-infected ticks after similar exposure. High mortality was observed in infected adults that were maintained for one month at a low or high temperature after tick-feeding on rabbits. CONCLUSION/SIGNIFICANCE: These preliminary results suggest that infected quiescent ticks may not survive the winter and may help explain the low prevalence of infected Rh. sanguineus in nature. Further investigations on the influence of extrinsic factors on diapaused R. conorii-infected and non-infected ticks are required.

  7. Rickettsia slovaca in immature Dermacentor marginatus and tissues from Apodemus spp. in the northern Apennines, Italy.

    Science.gov (United States)

    Martello, Elisa; Selmi, Marco; Ragagli, Charlotte; Ambrogi, Cecilia; Stella, Maria Cristina; Mannelli, Alessandro; Tomassone, Laura

    2013-12-01

    Immature Dermacentor marginatus ticks and tissues from small rodents were tested for infection with Rickettsia slovaca in the northern Apennines, Lucca Province, where tick-borne lymphadenopathy (TIBOLA) was previously reported in people. Prevalence of infestation with D. marginatus was 30.5% (n=131, 95% CI: 22.8-39.2%) in Apodemus spp. and 26.5% (n=34, 95% CI: 12.9-44.4%) in Myodes glareolus, which were captured during 1980 trap nights in 2009 and 2010. Rickettsia slovaca was identified by polymerase chain reaction, targeting the gltA and OmpA genes, in ear biopsies from 8 out of 37 tested Apodemus (22%, 95% CI: 9.8-38.2%), but not from 9 M. glareolus. The prevalence of R. slovaca in D. marginatus feeding on Apodemus spp. was 53% in larvae (n=51, 95% CI: 38.5-67.1%) and 47.5% in nymphs (n=59, 95% CI: 34.3-60.9%). No larvae (0.0%, 95% CI: 0-36.9%), but one nymph removed from M. glareolus was positive (10%, 95% CI: 0.3-44.5%). Prevalence of R. slovaca in host-seeking D. marginatus larvae, collected in the same area, was 42% (n=38; 95% CI: 26.3-59.2%). Prevalence of R. slovaca was greater in larvae feeding on PCR-positive Apodemus than in those feeding on negative mice (78.6% vs. 37.1%). Furthermore, levels of infestation with D. marginatus larvae were greater for R. slovaca-positive mice. The infection of Apodemus spp. was probably the result of repeated bites by transovarially infected larvae. On the other hand, the finding of R. slovaca in mice tissues would be compatible with transmission from these hosts to feeding D. marginatus. Based on such a hypothesis, the most heavily infested Apodemus might play a role as amplifiers of the infection.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Identification of Orientia tsutsugamushi,spotted fever group and typhus group Rickettsia by duplex and nested PCR methods

    Institute of Scientific and Technical Information of China (English)

    M-C Luan; D-Z Yu; L Tang; L-J Zhang

    2008-01-01

    Objective:To identify members of genera of rickettsia and O.tsutsugamushi simultaneously.Methods:Rapid and duplex and nested PCR methods have been established by designing primers based on the conserved re-gions of heat shock protein GroEL gene.345 mouse viscera samples including liver,spleen and kidney,96 Xe-nopsylla cheopis and 32 chiggers collected from Hongta areas of Yuxi city,Yunnan province were tested by the new PCR methods.Results:The result of the study showed that the new PCR methods could identify most members of genera -Rickettsia and Orientia simultaneously with 100% specificity and its sensitivity could test one copy per microliter.The results of detection prevalence of rickettsioses in mouse,flea and mites DNA sam-ples showed that the total rickettsia infection rate in mouse was 34.78% (120 /345).The total infection rates in R.typhi,O.t Karp and R.sibirica of mouse samples were 28.12% (97 /345),19.71% (68 /345)and 0. 29% (1 /345)respectively.Co-infection rates in R.typhi and O.t Karp of mouse samples were 13.33% (46 /345).O.t Karp type has been the main epidemic strain in these areas.Conclusion:We concluded that this PCR method could be used to detect multi-genera rickettsia simultaneously.Molecular evidences provided in this and previous studies strongly support that Hongta areas of Yuxi city are a natural focus for typhus and scrub typhus with the common occurrence of their confection.

  10. In vitro effectiveness of azithromycin against doxycycline-resistant and -susceptible strains of Rickettsia tsutsugamushi, etiologic agent of scrub typhus.

    OpenAIRE

    Strickman, D; Sheer, T; Salata, K.; Hershey, J; Dasch, G; Kelly, D.; Kuschner, R

    1995-01-01

    In an effort to find a potential alternative treatment for scrub typhus, we evaluated the effectiveness of the standard drug doxycycline and the new macrolide azithromycin against a doxycycline-susceptible strain (Karp) and a doxycycline-resistant strain (AFSC-4) of Rickettsia tsutsugamushi. The antibiotics were tested in an in vitro assay system in which infected mouse fibroblast cells (L929) were incubated for 3 days in various concentrations of the drugs. Rickettsial growth was evaluated b...

  11. Multispacer Typing (MST) of Spotted Fever Group Rickettsiae Isolated from Humans and Rats in Chengmai County, Hainan Province, China

    OpenAIRE

    Cheng, Xueqin; Jin, Yuming; Lao, Shijun; Huang, Changhe; Huang, Fang; Jia, Pengben; Zhang, Lijuan

    2014-01-01

    Spotted fever caused by spotted fever group rickettsiae (SFGR) is found throughout China. During 2007–2008, 28 human SFGR isolates and 34 rat SFGR isolates including 15 isolates from Rattus fulvescens, 5 isolates from R. edwardsi, 7 isolates from Callosciurus erythraeus roberti and 7 isolates from Dremomys rufigenis) were obtained from L929 cell culture. Previous research indicated that the 62 strains of SFGR mentioned above shared not only the same serophenotype but also 100% of identity seq...

  12. Molecular evidence of potential novel spotted fever group rickettsiae, Anaplasma and Ehrlichia species in Amblyomma ticks parasitizing wild snakes

    OpenAIRE

    Kho, Kai Ling; Koh, Fui Xian; Tay, Sun Tee

    2015-01-01

    Background Amblyomma ticks parasitize a wide range of animals in tropical regions. This study describes the identification of Amblyomma ticks from wild snakes in Malaysia and the detection of potential human pathogens such as Rickettsia, Anaplasma, Ehrlichia and bartonellae in the ticks. Findings Twenty one adult ticks (twelve A. varanense and nine Amblyomma helvolum ticks) identified from seven Python molurus snakes in Sepang and a pool of six A. helvolum ticks from a Naja sumatrana snake in...

  13. Spotted fever Rickettsia species in Hyalomma and Ixodes ticks infesting migratory birds in the European Mediterranean area

    OpenAIRE

    Wallmenius, Katarina; Barboutis, Christos; Fransson, Thord; Thomas G.T. Jaenson; Lindgren, Per-Eric; Nyström, Fredrik; Olsen, Bjorn; Salaneck, Erik; Nilsson, Kenneth

    2014-01-01

    Background: A few billion birds migrate annually between their breeding grounds in Europe and their wintering grounds in Africa. Many bird species are tick-infested, and as a result of their innate migratory behavior, they contribute significantly to the geographic distribution of pathogens, including spotted fever rickettsiae. The aim of the present study was to characterize, in samples from two consecutive years, the potential role of migrant birds captured in Europe as disseminators of Ric...

  14. Rickettsia parkeri: a Rickettsial pathogen transmitted by ticks in endemic areas for spotted fever rickettsiosis in southern Uruguay

    Directory of Open Access Journals (Sweden)

    José M. Venzal

    2012-06-01

    Full Text Available At first Rickettsia conorii was implicated as the causative agent of spotted fever in Uruguay diagnosed by serological assays. Later Rickettsia parkeri was detected in human-biting Amblyomma triste ticks using molecular tests. The natural vector of R. conorii, Rhipicephalus sanguineus, has not been studied for the presence of rickettsial organisms in Uruguay. To address this question, 180 R. sanguineus from dogs and 245 A. triste from vegetation (flagging collected in three endemic localities were screened for spotted fever group (SFG rickettsiosis in southern Uruguay. Tick extracted DNA pools were subjected to PCR using primers which amplify a fragment of the rickettsial gltA gene. Positive tick DNA pools with these primers were subjected to a second PCR round with primers targeting a fragment of the ompA gene, which is only present in SFG rickettsiae. No rickettsial DNA was detected in R. sanguineus. However, DNA pools of A. triste were found to be positive for a rickettsial organism in two of the three localities, with prevalences of 11.8% to 37.5% positive pools. DNA sequences generated from these PCR-positive ticks corresponded to R. parkeri. These findings, joint with the aggressiveness shown by A. triste towards humans, support previous data on the involvement of A. triste as vector of human infections caused by R. parkeri in Uruguay.

  15. Diversity of Bartonella and Rickettsia spp. in Bats and Their Blood-Feeding Ectoparasites from South Africa and Swaziland.

    Science.gov (United States)

    Dietrich, Muriel; Tjale, Mabotse A; Weyer, Jacqueline; Kearney, Teresa; Seamark, Ernest C J; Nel, Louis H; Monadjem, Ara; Markotter, Wanda

    2016-01-01

    In addition to several emerging viruses, bats have been reported to host multiple bacteria but their zoonotic threats remain poorly understood, especially in Africa where the diversity of bats is important. Here, we investigated the presence and diversity of Bartonella and Rickettsia spp. in bats and their ectoparasites (Diptera and Siphonaptera) collected across South Africa and Swaziland. We collected 384 blood samples and 14 ectoparasites across 29 different bat species and found positive samples in four insectivorous and two frugivorous bat species, as well as their Nycteribiidae flies. Phylogenetic analyses revealed diverse Bartonella genotypes and one main group of Rickettsia, distinct from those previously reported in bats and their ectoparasites, and for some closely related to human pathogens. Our results suggest a differential pattern of host specificity depending on bat species. Bartonella spp. identified in bat flies and blood were identical supporting that bat flies may serve as vectors. Our results represent the first report of bat-borne Bartonella and Rickettsia spp. in these countries and highlight the potential role of bats as reservoirs of human bacterial pathogens. PMID:26999518

  16. Rickettsia parkeri Transmission to Amblyomma americanum by Cofeeding with Amblyomma maculatum (Acari: Ixodidae) and Potential for Spillover.

    Science.gov (United States)

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

    2015-09-01

    Amblyomma americanum (L.) is a human-biting ixodid tick distributed throughout much of the southeastern United States. Rickettsia parkeri is a member of the spotted fever group rickettsiae and causes a febrile illness in humans commonly referred to as "Tidewater spotted fever" or "R. parkeri rickettsiosis." Although the Gulf Coast tick, Amblyomma maculatum Koch, is the primary vector of R. parkeri, a small proportion of A. americanum have also been shown to harbor R. parkeri. The purpose of this investigation was to determine whether R. parkeri is spilling over into A. americanum in eastern Virginia and also to determine through laboratory experiments, whether A. americanum can acquire R. parkeri by cofeeding alongside infected ticks. Of 317 wild-caught, flat adult A. americanum tested from 29 counties and independent cities in coastal Virginia, a single female A. americanum was positive for R. parkeri, suggesting that R. parkeri is spilling over into this species, but at very low rates (Rickettsia amblyommii, however, were less likely to acquire R. parkeri, suggesting that infection with R. amblyommii may prevent R. parkeri from establishing infection in A. americanum.

  17. Molecular characterization of Rickettsia massiliae and Anaplasma platys infecting Rhipicephalus sanguineus ticks and domestic dogs, Buenos Aires (Argentina).

    Science.gov (United States)

    Cicuttin, Gabriel L; Brambati, Diego F; Rodríguez Eugui, Juan I; Lebrero, Cecilia González; De Salvo, María N; Beltrán, Fernando J; Gury Dohmen, Federico E; Jado, Isabel; Anda, Pedro

    2014-09-01

    Rickettsioses, ehrlichioses and anaplasmoses are emerging diseases that are mainly transmitted by arthropods and that affect humans and animals. The aim of the present study was to use molecular techniques to detect and characterize those pathogens in dogs and ticks from Buenos Aires city. We studied 207 Rhipicephalus sanguineus ticks and 52 canine blood samples from poor neighborhoods of Buenos Aires city. The samples were molecularly screened for the genera Rickettsia, Ehrlichia, and Anaplasma by PCR and sequencing. DNA of Rickettsia massiliae (3.4%) and Anaplasma platys (13.5%) was detected in ticks and blood samples, respectively. For characterization, the positive samples were subjected to amplification of a fragment of the 190-kDa outer membrane protein gene (spotted fever group rickettsiae) and a fragment of the groESL gene (specific for A. platys). A phylogenetic tree was constructed using the neighbor-joining method, revealing that the sequences were closely related to those of strains from other geographic regions. The results indicate that human and animal pathogens are abundant in dogs and their ticks in Buenos Aires city and portray the potentially high risk of human exposure to infection with these agents, especially in poor neighborhoods, where there is close contact with animals in an environment of poor health conditions.

  18. Diversity of Bartonella and Rickettsia spp. in Bats and Their Blood-Feeding Ectoparasites from South Africa and Swaziland.

    Science.gov (United States)

    Dietrich, Muriel; Tjale, Mabotse A; Weyer, Jacqueline; Kearney, Teresa; Seamark, Ernest C J; Nel, Louis H; Monadjem, Ara; Markotter, Wanda

    2016-01-01

    In addition to several emerging viruses, bats have been reported to host multiple bacteria but their zoonotic threats remain poorly understood, especially in Africa where the diversity of bats is important. Here, we investigated the presence and diversity of Bartonella and Rickettsia spp. in bats and their ectoparasites (Diptera and Siphonaptera) collected across South Africa and Swaziland. We collected 384 blood samples and 14 ectoparasites across 29 different bat species and found positive samples in four insectivorous and two frugivorous bat species, as well as their Nycteribiidae flies. Phylogenetic analyses revealed diverse Bartonella genotypes and one main group of Rickettsia, distinct from those previously reported in bats and their ectoparasites, and for some closely related to human pathogens. Our results suggest a differential pattern of host specificity depending on bat species. Bartonella spp. identified in bat flies and blood were identical supporting that bat flies may serve as vectors. Our results represent the first report of bat-borne Bartonella and Rickettsia spp. in these countries and highlight the potential role of bats as reservoirs of human bacterial pathogens.

  19. Rickettsia parkeri: a Rickettsial pathogen transmitted by ticks in endemic areas for spotted fever rickettsiosis in southern Uruguay.

    Science.gov (United States)

    Venzal, José M; Estrada-Peña, Agustín; Portillo, Aránzazu; Mangold, Atilio J; Castro, Oscar; De Souza, Carlos G; Félix, María L; Pérez-Martínez, Laura; Santibánez, Sonia; Oteo, José A

    2012-01-01

    At first Rickettsia conorii was implicated as the causative agent of spotted fever in Uruguay diagnosed by serological assays. Later Rickettsia parkeri was detected in human-biting Amblyomma triste ticks using molecular tests. The natural vector of R. conorii, Rhipicephalus sanguineus, has not been studied for the presence of rickettsial organisms in Uruguay. To address this question, 180 R. sanguineus from dogs and 245 A. triste from vegetation (flagging) collected in three endemic localities were screened for spotted fever group (SFG) rickettsiosis in southern Uruguay. Tick extracted DNA pools were subjected to PCR using primers which amplify a fragment of the rickettsial gltA gene. Positive tick DNA pools with these primers were subjected to a second PCR round with primers targeting a fragment of the ompA gene, which is only present in SFG rickettsiae. No rickettsial DNA was detected in R. sanguineus. However, DNA pools of A. triste were found to be positive for a rickettsial organism in two of the three localities, with prevalences of 11.8% to 37.5% positive pools. DNA sequences generated from these PCR-positive ticks corresponded to R. parkeri. These findings, joint with the aggressiveness shown by A. triste towards humans, support previous data on the involvement of A. triste as vector of human infections caused by R. parkeri in Uruguay.

  20. 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.

  1. Rickettsia helvetica and R. monacensis infections in immature Ixodes ricinus ticks derived from sylvatic passerine birds in west-central Poland.

    Science.gov (United States)

    Biernat, Beata; Stańczak, Joanna; Michalik, Jerzy; Sikora, Bożena; Cieniuch, Stella

    2016-09-01

    The aim of this study was to assess the importance of forest passerine birds in spreading ixodid ticks infected with rickettsiae of spotted fever group (SFG) in sylvatic habitats in western Poland. In total, 834 immature Ixodes ricinus ticks were found on 64 birds of 11 species which were captured during the tick-questing season between May and September of 2006. Ground-foraging passerines hosted most of the ticks compared with arboreal species, and therefore, only the former group was included into a detailed analysis. Significant predominance of larvae over nymphs was observed (581 vs. 253, respectively). Blackbirds and song thrushes hosted 82 % (n = 681) of the ticks collected from all infested passerines. The overall prevalence range of SF rickettsiae (including Rickettsia helvetica and Rickettsia monacensis) in bird-derived ticks was 10.5-26.9 %, exceeding that in questing ticks, and in ticks feeding on rodents and deer reported earlier from the same study area. This high prevalence of infection in immature I. ricinus ticks feeding on passerine birds strongly implies that they are involved in the enzootic maintenance of spotted fever group rickettsiae in the tick vector populations occurring in sylvatic habitats. PMID:27164834

  2. 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.

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

    Science.gov (United States)

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

    2013-03-01

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

  4. 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. PMID:27074326

  5. Transcriptional analysis of Rickettsia prowazekii invasion gene homolog (invA) during host cell infection.

    Science.gov (United States)

    Gaywee, Jariyanart; Radulovic, Suzana; Higgins, James A; Azad, Abdu F

    2002-11-01

    An invasion gene homolog, invA, of Rickettsia prowazekii has recently been identified to encode a member of the Nudix hydrolase subfamily which acts specifically on dinucleoside oligophosphates (Np(n)N; n >/= 5), a group of cellular signaling molecules known as alarmones. InvA is thought to enhance intracellular survival by regulating stress-induced toxic nucleotide levels during rickettsial infection. To further characterize the physiological function of InvA, the gene expression pattern during various stages of rickettsial intracellular growth was investigated. Using semiquantitative reverse transcription-PCR (RT-PCR) and real-time fluorescent probe-based quantitative RT-PCR, a differential expression profile of invA during rickettsial host cell infection was examined. The invA transcript temporarily increased during the early period of infection. Expression of rickettsial groEL, a molecular indicator of cellular stresses, was also shown to be upregulated during the early period of infection. Furthermore, invA was cotranscribed in a polycistronic message with rrp, a gene encoding the response regulator protein homolog, which is a part of a two-component signal transduction system. These results support our earlier findings that under such stress conditions dinucleoside oligophosphate pyrophosphatase may function as a buffer, enhancing rickettsial survival within the cytoplasm of a eukaryotic cell. The expression of rickettsial dinucleoside oligophosphate pyrophosphatase may be regulated by a part of the two-component signal transduction system similar to that described for response regulators in other bacterial systems.

  6. 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 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. PMID:27074326

  7. Prevalence and infection load dynamics of Rickettsia felis in actively feeding cat fleas.

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    Kathryn E Reif

    Full Text Available BACKGROUND: Rickettsia felis is a flea-associated rickettsial pathogen recurrently identified in both colonized and wild-caught cat fleas, Ctenocephalides felis. We hypothesized that within colonized fleas, the intimate relationship between R. felis and C. felis allows for the coordination of rickettsial replication and metabolically active periods during flea bloodmeal acquisition and oogenesis. METHODOLOGY/PRINCIPAL FINDINGS: A quantitative real-time PCR assay was developed to quantify R. felis in actively feeding R. felis-infected fleas. In three separate trials, fleas were allowed to feed on cats, and a mean of 3.9x10(6 R. felis 17-kDa gene copies was detected for each flea. A distinct R. felis infection pattern was not observed in fleas during nine consecutive days of bloodfeeding. However, an inverse correlation between the prevalence of R. felis-infection, which ranged from 96% in Trial 1 to 35% in Trial 3, and the R. felis-infection load in individual fleas was identified. Expression of R. felis-infection load as a ratio of R. felis/C. felis genes confirmed that fleas in Trial 3 had significantly greater rickettsial loads than those in Trial 1. CONCLUSION/SIGNIFICANCE: Examining rickettsial infection dynamics in the flea vector will further elucidate the intimate relationship between R. felis and C. felis, and facilitate a more accurate understanding of the ecology and epidemiology of R. felis transmission in nature.

  8. Nuclear Magnetic Resonance (NMR) as a tool for the study of the metabolism of Rickettsia slovaca.

    Science.gov (United States)

    García-Álvarez, Lara; Busto, Jesús H; Peregrina, Jesús M; Santibáñez, Sonia; Portillo, Aránzazu; Avenoza, Alberto; Oteo, José A

    2015-01-01

    Rickettsial infections are caused by intracellular bacteria. They do not grow in standard culture media so there are limitations in routine practice to study their metabolism. Nuclear Magnetic Resonance (NMR) spectroscopy is used for identification of metabolites in biological samples. Vero cells infected with Rickettsia slovaca as well as uninfected cells were monitored by (1)H NMR showing the presence of ethanol and lactic acid. As no differences were observed, labeled compounds were added into cultures. When D-[1-13C]glucose was monitored by (13)C NMR no differences among infected and uninfected cells were observed in metabolic profiles. Glucose was transformed into ethanol in all cultures. Monitored experiments carried out with [2-13C]glycine showed differences between infected and uninfected cell cultures spectra. Glycine was partially transformed into serine, but the amount of the serine formed was larger in those infected. Moreover, L-[2-13C]leucine, L-[1-13C]isoleucine and L-[15N]tyrosine were evaluated. No differences among infected and uninfected cells were observed in the metabolic profiles when tyrosine and leucine were monitored. The amino acid L-[1-13C]isoleucine exhibited different metabolism in presence of the R. slovaca, showing a promising behavior as biomarker. In this work we focused on finding one or more compounds that could be metabolized specifically by R. slovaca and could be used as an indicator of its activity.

  9. Genomic, proteomic, and transcriptomic analysis of virulent and avirulent Rickettsia prowazekii reveals its adaptive mutation capabilities.

    Science.gov (United States)

    Bechah, Yassina; El Karkouri, Khalid; Mediannikov, Oleg; Leroy, Quentin; Pelletier, Nicolas; Robert, Catherine; Médigue, Claudine; Mege, Jean-Louis; Raoult, Didier

    2010-05-01

    Rickettsia prowazekii, the agent of epidemic typhus, is an obligate intracellular bacterium that is transmitted to human beings by the body louse. Several strains that differ considerably in virulence are recognized, but the genetic basis for these variations has remained unknown since the initial description of the avirulent vaccine strain nearly 70 yr ago. We use a recently developed murine model of epidemic typhus and transcriptomic, proteomic, and genetic techniques to identify the factors associated with virulence. We identified four phenotypes of R. prowazekii that differed in virulence, associated with the up-regulation of antiapoptotic genes or the interferon I pathway in the host cells. Transcriptional and proteomic analyses of R. prowazekii surface protein expression and protein methylation varied with virulence. By sequencing a virulent strain and using comparative genomics, we found hotspots of mutations in homopolymeric tracts of poly(A) and poly(T) in eight genes in an avirulent strain that split and inactivated these genes. These included recO, putative methyltransferase, and exported protein. Passage of the avirulent Madrid E strain in cells or in experimental animals was associated with a cascade of gene reactivations, beginning with recO, that restored the virulent phenotype. An area of genomic plasticity appears to determine virulence in R. prowazekii and represents an example of adaptive mutation for this pathogen. PMID:20368341

  10. Rickettsia-like organism infection in a freshwater cultured fish Ophiocephalus argus C.in China

    Institute of Scientific and Technical Information of China (English)

    GUO Qionglin; JIA Weizhang; HAN Xianpu; CAI Taozhen; GONG Xiaoning; SUN Xiaofeng

    2004-01-01

    From 2001 to 2002,a new and emergent infectious disease of Ophiocephalus argus occurred in a fishery in Hubei Province,China,with an incidence of 60%~70% and a mortality as high as 100%.The diseased fish showed an enlarged abdomen,the millet-like nodules in internal organs,and the swollen kidney which was composed of 5~10 sarcoma-like bodies in cream or gray-white colour or ulcerated into beandregs-like substance.Light microscopic observation revealed the basophilic or acidphilic inclusions in cytoplasm of the cells and the granulomas,a diffusive chronic inflammation in internal organs.Further analysis under an electron microscope indicated that the intracytoplasmic inclusions were rickettsia-like organisms (RLOs) that are either spherical or coccoid,with variable size,ranging from 0.5~1.5 μm in diameter,and enclosed within membrane-bound cytoplasmic vacuoles.RLO had a central nucleoid region with some fine filamentous structures and an electron-dense granule.Its cytoplasm contained abundant ribosomal bodies.Occasionally,RLO appeared to be divided by binary fission.RLOs were also observed in the homogenized tissue of infected fish.The results suggested that the death of cultured O.Argus was caused by RLO infection.

  11. Possible Role of Rickettsia felis in Acute Febrile Illness among Children in Gabon.

    Science.gov (United States)

    Mourembou, Gaël; Lekana-Douki, Jean Bernard; Mediannikov, Oleg; Nzondo, Sydney Maghendji; Kouna, Lady Charlene; Essone, Jean Claude Biteghe Bi; Fenollar, Florence; Raoult, Didier

    2015-10-01

    Rickettsia felis has been reported to be a cause of fever in sub-Saharan Africa, but this association has been poorly evaluated in Gabon. We assessed the prevalence of this bacterium among children Gabon; the locations were in urban, semiurban, and rural areas. DNA samples from 410 febrile children and 60 afebrile children were analyzed by quantitative PCR. Overall, the prevalence of R. felis among febrile and afebrile children was 10.2% (42/410 children) and 3.3% (2/60 children), respectively. Prevalence differed among febrile children living in areas that are urban (Franceville, 1.3% [1/77]), semiurban (Koulamoutou, 2.1% [3/141]), and rural (Lastourville, 11.2% [15/134]; Fougamou, 39.7% [23/58]). Furthermore, in a rural area (Fougamou), R. felis was significantly more prevalent in febrile (39.7% [23/58]) than afebrile children (5.0% [1/20]). Additional studies are needed to better understand the pathogenic role of R. felis in this part of the world.

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

    Science.gov (United States)

    Bowman, Dwight D

    2011-11-01

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

  13. 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.

  14. Detección de Rickettsia spp. en Garrapatas de Myrmecophaga tridactyla de Vida Libre en la Sabana Inundable de Casanare‚ Colombia -resumen-

    OpenAIRE

    César Rojano-Bolaño; R Ávila-Avilán; L Miranda-Cortés; V Contreras-Cogollo; Jorge Miranda-Regino; Laura Hernández-Fernández; Salim Mattar-Velilla; Santiago Monsalve-Buriticá; J Carrascal-Velásquez

    2014-01-01

    Las bacterias del género Rickettsia son organismos con distribución mundial‚ causantes de algunas enfermedades zoonóticas de gran importancia en salud pública. Sin embargo‚ en Colombia son pocos los estudios enfocados a conocer su distribución y los vectores involucrados. El objetivo de este estudio fue detectar la presencia de Rickettsia spp.‚ en garrapatas colectadas en nueve osos palmeros (Myrmecophaga tridactyla) de vida libre en el municipio de Pore‚ Casanare‚ entre los años 2013 y 2014....

  15. Lyme borreliosis spirochetes and spotted fever group rickettsiae in ixodid ticks from Pianosa island, Tuscany Archipelago, Italy.

    Science.gov (United States)

    Tomassone, L; Grego, E; Auricchio, D; Iori, A; Giannini, F; Rambozzi, L

    2013-02-01

    A study on tick fauna and tick-borne pathogens was undertaken in Pianosa, an island in the Tuscany Archipelago that constitutes an important stopping and nesting point for migratory birds. Ticks were removed from feral cats and a few terrestrial birds, and host-seeking ticks were collected by dragging. A total of 89 ticks were found on animals: 57 Ixodes ventalloi Gil Collado, 1936 and 32 Ixodes acuminatus Neumann, 1901. Host-seeking ticks were 354 Hyalomma spp. larvae and 18 Hyalomma spp. adults, identified as Hyalomma marginatum C.L. Koch, 1844 (n=11) and 7 Hyalomma detritum Schulze, 1919 (n=7). A sample of adult ticks was subjected to molecular analyses to look for Rickettsia spp. and Borrelia burgdorferi sensu lato (s.l.). Sequence analysis of the 5S-23S intergenic spacer region and OspA gene of B. burgdorferi s.l.-positive samples showed the presence of Borrelia spielmanii (n=3; 3.7%, 95% confidence interval [CI] 0.08-10.4) and Borrelia valaisiana (n=13; 13.6%, 95% CI 7.0-23.0) in Ixodes ticks from cats and terrestrial birds. Ixodes spp. were also infected by Rickettsia helvetica (n=19; 23.4%, 95% CI 14.7-34.2). Finally, we detected Rickettsia aeschlimannii in 3 out of 12 host-seeking Hyalomma spp. adults tested (25%, 95% CI 5.5-57.2). Our study shows the presence of several tick-borne pathogens in Pianosa. Hyalomma spp. and Ixodes ticks other than I. ricinus seem to be involved in their epidemiological cycle, and birds could contribute to the pathogen dispersal along their migration routes. This is the first finding of B. spielmanii in Italy. We hypothesize the involvement of peridomestic rodents or hedgehogs in its maintenance in Pianosa.

  16. A Molecular survey of Anaplasma spp., Rickettsia spp., Ehrlichia canis and Babesia microti in foxes and fleas from Sicily.

    Science.gov (United States)

    Torina, A; Blanda, V; Antoci, F; Scimeca, S; D'Agostino, R; Scariano, E; Piazza, A; Galluzzo, P; Giudice, E; Caracappa, S

    2013-11-01

    Fleas (Insecta: Siphonaptera) are obligate bloodsucking insects, which parasitize birds and mammals, and are distributed throughout the world. Several species have been implicated in pathogen transmission. This study aimed to monitor red foxes and the fleas isolated from them in the Palermo and Ragusa provinces of Sicily, Italy, as these organisms are potential reservoirs and vectors of pathogens. Thirteen foxes (Vulpes vulpes) and 110 fleas were analysed by polymerase chain reaction (PCR) to detect DNA of the pathogens Ehrlichia canis, Babesia microti, Rickettsia spp., Anaplasma phagocytophilum, Anaplasma platys, Anaplasma marginale and Anaplasma ovis. In the foxes, A. ovis was detected in only one animal, whereas the prevalence of the E. canis pathogen was 31%. B. microti and Rickettsia spp. were not detected. Of all of the collected fleas, 75 belonged to the species Xenopsylla cheopis, 32 belonged to Ctenocephalides canis, two belonged to Ctenocephalides felis and one belonged to Cediopsylla inaequalis. In the fleas, the following pathogens were found: A. ovis (prevalence 25%), A. marginale (1%), A. phagocytophilum (1%), Rickettsia felis (2%) and E. canis (3%). X. cheopis was the flea species most frequently infected with Anaplasma, in particular A. ovis (33%), A. marginale (1%) and A. phagocytophilum (1%). Both C. felis exemplars were positive for R. felis. E. canis was found in the lone C. inaequalis and also in 3% of the X. cheopis specimens. No fleas were positive for B. microti or A. platys. As foxes often live in proximity to domestic areas, they may constitute potential reservoirs for human and animal parasites. Further studies should be performed on fleas to determine their vectorial capacity.

  17. Celulitis por citomegalovirus

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    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

  18. Serosurvey for tick-borne diseases in dogs from the Eastern Amazon, Brazil Pesquisa Sorológica por doenças transmitidas por carrapatos em cães da Amazônia oriental, Brasil

    Directory of Open Access Journals (Sweden)

    Mariana Granziera Spolidorio

    Full Text Available Canine ehrlichiosis and babesiosis are the most prevalent tick-borne diseases in Brazilian dogs. Few studies have focused attention in surveying tick-borne diseases in the Brazilian Amazon region. A total of 129 blood samples were collected from dogs living in the Brazilian eastern Amazon. Seventy-two samples from dogs from rural areas of 19 municipalities and 57 samples from urban stray dogs from Santarém municipality were collected. Serum samples were submitted to Indirect Immunofluorescence Assay (IFA with antigens of Babesia canis vogeli, Ehrlichia canis, and six Rickettsia species. The frequency of dogs containing anti-B. canis vogeli, anti-E. canis, and anti-Rickettsia spp. antibodies was 42.6%, 16.2%, and 31.7%, respectively. Anti-B. canis vogeli antibodies were detected in 59.6% of the urban dogs, and in 29.1% of the rural dogs (P Ehrliquiose canina e babesiose canina são as doenças parasitárias transmitidas por carrapatos de maior prevalência em cães do Brasil. Poucos estudos pesquisaram doenças transmitidas por carrapatos na região da Amazônia brasileira. Um total de 129 amostras de sangue foram colhidas de cães da Amazônia oriental brasileira. Setenta e dois cães eram de áreas rurais de 19 municípios do Estado do Pará, e 57 amostras foram colhidas de cães errantes vadios da área urbana do município de Santarém-PA. As amostras de soro foram submetidas ao ensaio de imunofluorescência indireta, com antígenos de Babesia canis vogeli, Ehrlichia canis, e seis espécies de Rickettsia. A frequência de cães com anticorpos anti-B. canis vogeli, anti-E. canis, e anti-Rickettsia spp. foi de 42,6%, 16,2% e 31,7%, respectivamente. Anticorpos anti-B. canis vogeli foram detectados em 59,6% dos cães urbanos, e em 29,1% dos cães rurais (P < 0.05. Para E. canis, a soroprevalência foi parecida entre os cães urbanos (15,7% e rurais (16,6%. Para Rickettsia spp., cães rurais apresentaram prevalência (P < 0.05 significativamente

  19. 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.

  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 BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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)

    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. The role of cottontail rabbits (Sylvilagus spp.) in the ecology of Rickettsia rickettsii in the United States.

    Science.gov (United States)

    Burgdorfer, W; Cooney, J C; Mavros, A J; Jellison, W L; Maser, C

    1980-07-01

    Rocky Mountain (Sylvilagus nuttallii) and eastern (S. floridanus) cottontails were examined for their susceptibility to virulent and avirulent strains of the spotted fever agent, Rickettsia rickettsii. Both species of rabbits responded to inoculation of yolk sac suspensions containing 500 egg LD50 of either virulent or avirulent rickettsiae, with rickettsemias detectable as early as 3 days after inoculation and lasting up to 7 days. When fed upon by infected ticks, only one of three Rocky Mountain and one of four eastern cottontails developed rickettsemias detectable in embryonated hens' eggs. Rickettsial concentrations in the peripheral blood fo Rocky Mountain cottontails, infected either by syringe or by bites of one or more Dermacentor andersoni ticks harboring virulent R. rickettsii, were sufficient to infect simultaneously feeding normal larvae of this tick species. However, infection rates wre low and did not exceed 11.7%. In a single experiment, the bites of D. variabilis, infected with an avirulent strain of R. rickettsii, did not produce rickettsemias sufficient to infect normal D. variabilis larvae. These laboratory findings suggest that cottontail rabbits, although susceptible to R. rickettsii, do not serve as efficient reservoirs for infecting ticks. PMID:7406116

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

    International Nuclear Information System (INIS)

    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

  4. Detection and prevalence of Anaplasma phagocytophilum and Rickettsia helvetica in Ixodes ricinus ticks in seven study areas in Sweden

    Directory of Open Access Journals (Sweden)

    Falk Kerstin

    2010-08-01

    Full Text Available Abstract Background Tick-borne Anaplasma phagocytophilum and Rickettsia spp. are considered to be emerging human pathogens, but only limited data are available on their occurrence in Sweden. Two real-time PCR assays followed by nested PCR and sequence analysis were carried out to investigate the prevalence of A. phagocytophilum and spotted fever rickettsiae in ticks from seven areas in Sweden. Results In 139 pooled samples, representing a total of 1245 Ixodes ricinus ticks (204 larvae, 963 nymphs, 38 males, 40 females, the overall positive mean infection prevalence was 1.3-15.0% for A. phagocytophilum and 1.5-17.3% for R. helvetica. A. phagocytophilum was only detected in nymphs (1.7-19.4%, whereas R. helvetica was detected in all three tick stages. Support for vertical and transstadial transmission was only obtained for R. helvetica. Both agents showed similar infection rates across study areas, although infection rates were greater in coastal areas. Conclusions The results show that both pathogens occurred in all seven locations, indicating that they are prevalent in Sweden and should be considered etiological agents in patients recently bitten by ticks.

  5. SNP-based real-time pyrosequencing as a sensitive and specific tool for identification and differentiation of Rickettsia species in Ixodes ricinus ticks

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    Janecek Elisabeth

    2012-10-01

    Full Text Available Abstract Background Rickettsioses are caused by pathogenic species of the genus Rickettsia and play an important role as emerging diseases. The bacteria are transmitted to mammal hosts including humans by arthropod vectors. Since detection, especially in tick vectors, is usually based on PCR with genus-specific primers to include different occurring Rickettsia species, subsequent species identification is mainly achieved by Sanger sequencing. In the present study a real-time pyrosequencing approach was established with the objective to differentiate between species occurring in German Ixodes ticks, which are R. helvetica, R. monacensis, R. massiliae, and R. felis. Tick material from a quantitative real-time PCR (qPCR based study on Rickettsia-infections in I. ricinus allowed direct comparison of both sequencing techniques, Sanger and real-time pyrosequencing. Methods A sequence stretch of rickettsial citrate synthase (gltA gene was identified to contain divergent single nucleotide polymorphism (SNP sites suitable for Rickettsia species differentiation. Positive control plasmids inserting the respective target sequence of each Rickettsia species of interest were constructed for initial establishment of the real-time pyrosequencing approach using Qiagen’s PSQ 96MA Pyrosequencing System operating in a 96-well format. The approach included an initial amplification reaction followed by the actual pyrosequencing, which is traceable by pyrograms in real-time. Afterwards, real-time pyrosequencing was applied to 263 Ixodes tick samples already detected Rickettsia-positive in previous qPCR experiments. Results Establishment of real-time pyrosequencing using positive control plasmids resulted in accurate detection of all SNPs in all included Rickettsia species. The method was then applied to 263 Rickettsia-positive Ixodes ricinus samples, of which 153 (58.2% could be identified for their species (151 R. helvetica and 2 R. monacensis by previous custom

  6. Survey of ticks (Acari: Ixodidae) and their rickettsia in an Atlantic rain forest reserve in the State of São Paulo, Brazil.

    Science.gov (United States)

    Sabatini, Guilherme S; Pinter, Adriano; Nieri-Bastos, Fernanda A; Marcili, Arlei; Labruna, Marcelo B

    2010-09-01

    The current study investigated the occurrence of ticks and their rickettsiae in the Serra do Mar State Park, which encompasses one of the largest Atlantic rain forest reserves of Brazil. From July 2008 to June 2009, a total of 2439 ticks (2,196 free living and 243 collected on hosts) was collected, encompassing the following 13 species: Amblyomma aureolatum (Pallas), Amblyomma brasiliense AragAo, Amblyomma dubitatum Neumann, Amblyomma fuscum Neumann, Amblyomma incisum Neumann, Amblyomma longirostre (Koch), Amblyomma naponense (Packard), Amblyomma nodosum Neumann, Amblyomma ovale Koch, Haemaphysalis juxtakochi Cooley, Ixodes aragaoi Fonseca, Ixodes loricatus Neumann, and Rhipicephalus sanguineus (Latreille). Ticks were submitted to polymerase chain reaction assays targeting portions of the rickettsial genes gltA and ompA. Polymerase chain reaction products were DNA sequenced and compared with corresponding sequences available in GenBank. Rickettsia bellii, a rickettsia of unknown pathogenicity, was detected in one A. aureolatum, one A. ovale, and three A. incisum specimens. At least 8.8% (3/34) of the free-living A. ovale ticks, 13.6% (8/59) of the A. ovale ticks collected from dogs, and 1.9% (1/54) of the R. sanguineus (Latreille) ticks were found to be infected by Rickettsia sp strain Atlantic rain forest, a novel strain that has been shown to cause an eschar-associated spotted fever in the state of Sho Paulo. Our results suggest that A. ovale is the vector of Rickettsia sp strain Atlantic rain forest in the state of São Paulo. PMID:20939390

  7. 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. PMID:24582511

  8. 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.

  9. Analysis of the Gut Microbes of the Chinese White Wax Scale Ericerus pela and Molecular Detection of Rickettsia%白蜡虫肠道微生物分析及立克次氏体分子检测

    Institute of Scientific and Technical Information of China (English)

    徐冬丽; 刘魏魏; 胡艳红; 杨璞; 陈晓鸣

    2012-01-01

    To understand the diversity of the gut microbes of Chinese white wax scale Ericerus pela, 16S rDNA clone library was constructed to analyze the gut microbes of the female E. pela adults. The results showed that, the gut of E. pela contained abundant of Rickettsia. Gut microbes Arsenophonus and Variovorax were also been identified. And Rickettsia was the main bacteria in gut of E. pela. The phylogenetic analysis of the 16S rDNA showed that, the Rickettsia from E. pela has close relationship with that of pea aphid Acyrthosiphon pisum. PCR amplification was performed using the specific primers for Rickettsia to detect infection in 30 male and 30 female individuals. The result showed that, the infected male and female were 24 and 12 respectively.

  10. 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

  11. 黑龙江口岸斑点热群立克次体调查研究%INVESTIGATION OF SPOTTED FEVER GROUP RICKETTSIA IN HEILONGJIANG PORT

    Institute of Scientific and Technical Information of China (English)

    鞠文东; 程成; 付维明; 王延禄; 呼满霞; 梁慧杰; 王红霞; 徐宁; 耿聪

    2015-01-01

    为了解黑龙江口岸地区斑点热群立克次体在人群、鼠类、蜱类中的分布特征,针对黑龙江省9个中俄边境口岸,采集出入境人群的血液样本215份、鼠类样本204份、蜱类样本188份,利用半巢式PCR方法对所有样本进行斑点热群立克次体特异性片段扩增,通过基因测序对斑点热群立克次体分型。结果在哈尔滨机场及嘉荫两个口岸的大仓鼠及小家鼠中检测到2例劳氏立克次体Rickettsia raoultii,为首次在黑龙江口岸鼠样本中检测出劳氏立克次体;在188份蜱样本中,检出斑点热群立克次体阳性样本101例,感染率达53.7%,其中劳氏立克次体89例,新塔拉塞维奇立克次体Candidatus Rickettsia tarasevichiae 11例,黑龙江立克次体Rickettsia heilongjiangii 1例,同样首次在黑龙江口岸全沟硬蜱中检测到新塔拉塞维奇立克次体。黑龙江中俄边境口岸开展SFGR的长期监测具有非常重要的公共卫生学意义。%To understand the distribution characteristics of spotted fever group Rickettsia in the residencies, rodents and ticks in Heilongjiang ports, total 9 port area along with Sino-Russian border were sampled to test the species and infection rates of spotted fever group Rickettsia from 188 ticks and 204 rodents.Moreover, 215 humans entry or exit from these ports were also include for screening the possible infection the rickettsia organisms under their permissions.Results from semi-nested PCR and sequences indicated that two Rickettsia raoultii detected in Cricetulus triton and Mus musculus Linnaeus respectively.None rickettsia organism were found in the human samples.While in ticks, 90 R.raoultii, 11 Candidatus Rickettsia tarasevichiae and 1 R.heilongiangii were found.The preliminary suggested the risk of emerged spotted fever pathogens in these areas and the necessary and urgent of long term monitoring on tick borne diseases.

  12. Static and dynamic systems in Rickettsia slovaca life cycle evaluated by quantitative real-time polymerase chain reaction.

    Science.gov (United States)

    Spitalská, E; Sparagano, O; Boldis, V

    2010-04-01

    Quantitative real-time polymerase chain reaction was used to characterize the growth of Rickettsia slovaca, a tick-borne pathogen transmitted by Dermacentor reticulatus and D. marginatus ticks, in static (L929 and Vero cells) and dynamic (D. marginatus and Ixodes ricinus ticks) cultivation systems. The highest points of bacterial multiplication and the time-spans between the inoculum and the maximum of rickettsial copies were increased in consecutive order from eukaryotic cells, I. ricinus to D. marginatus systems. In dynamic system, multiplication maximum of R. slovaca was achieved 9 days earlier in I. ricinus; however, the number of rickettsial DNA copies was approximately 3.6 x 10(6) more in D. marginatus. PMID:20537110

  13. A rickettsia-like organism from Ixodes uriae ticks collected on the Kerguelen Islands (French Subantarctic Territories).

    Science.gov (United States)

    Chastel, C; Demazure, M; Chastel, O; Genevois, F; Legrand, M C; Grulet, O; Odermatt, M; Le Goff, F

    1993-02-01

    A rickettsia-like microorganism was isolated in suckling mice from Ixodes uriae ticks collected from penguins breeding on Mayes Island, Kerguelen Archipelago, French Subantarctic Territories. At isolation, this agent mimicked a tick-borne arbovirus. Finally, electron microscopy studies of infected suckling mouse livers showed the presence of inclusions filled with pleomorphic microorganism in the cytoplasm of some hepatocytes, sometimes dividing by binary fission and thus of obviously non-viral nature. No firm serological relationship was demonstrated with Chlamydia psittaci, C. trachomatis, C. pneumoniae, Coxiella burnetti, Cowdria ruminentium, Ehrlichia canis, E. phagocytophila, E. risticii or the WSU/1044 agent. The exact taxonomic position of the "Mayes" agent remains to be clarified. PMID:8105647

  14. Prevalence, Distribution, and Development of an Ecological Niche Model of Dermacentor variabilis Ticks Positive for Rickettsia montanensis.

    Science.gov (United States)

    St John, Heidi K; Adams, Melissa L; Masuoka, Penny M; Flyer-Adams, Johanna G; Jiang, Ju; Rozmajzl, Patrick J; Stromdahl, Ellen Y; Richards, Allen L

    2016-04-01

    Rickettsia montanensis has long been considered a nonpathogenic member of the spotted fever group rickettsiae. However, the infection potential of R. montanensis is being revisited in light of its recent association with a case of human infection in the United States and the possibility that additional cases may have been misdiagnosed as Rocky Mountain spotted fever. To this end, DNA was extracted from American dog ticks (Dermacentor variabilis) removed from Department of Defense (DoD) personnel and their dependents at DoD medical treatment facilities (MTFs) during 2002-2012 (n = 4792). These 4792 samples were analyzed for the presence of R. montanensis (n =  36; 2.84%) and all vector DNA was confirmed to be of D. variabilis origin using a novel Dermacentor genus-specific quantitative real-time polymerase chain reaction procedure, Derm, and a novel Dermacentor species multilocus sequence typing assay. To assess the risk of R. montanensis infection, the positive and negative samples were geographically mapped utilizing MTF site locations. Tick localities were imported into a geographical information systems (GIS) program, ArcGIS, for mapping and analysis. The ecological niche modeling (ENM) program, Maxent, was used to estimate the probability of tick presence in eastern United States using locations of both R. montanensis-positive and -negative ticks, climate, and elevation data. The ENM for R. montanensis-positive D. variabilis estimated high probabilities of the positive ticks occurring in two main areas, including the northern Midwest and mid-Atlantic portions of the northeastern regions of United States, whereas the R. montanensis-negative D. variabilis tick model showed a wider estimated range. The results suggest that R. montanensis-positive and -negative D. variabilis have different ranges where humans may be at risk and are influenced by similar and different factors.

  15. Prevalence, Distribution, and Development of an Ecological Niche Model of Dermacentor variabilis Ticks Positive for Rickettsia montanensis.

    Science.gov (United States)

    St John, Heidi K; Adams, Melissa L; Masuoka, Penny M; Flyer-Adams, Johanna G; Jiang, Ju; Rozmajzl, Patrick J; Stromdahl, Ellen Y; Richards, Allen L

    2016-04-01

    Rickettsia montanensis has long been considered a nonpathogenic member of the spotted fever group rickettsiae. However, the infection potential of R. montanensis is being revisited in light of its recent association with a case of human infection in the United States and the possibility that additional cases may have been misdiagnosed as Rocky Mountain spotted fever. To this end, DNA was extracted from American dog ticks (Dermacentor variabilis) removed from Department of Defense (DoD) personnel and their dependents at DoD medical treatment facilities (MTFs) during 2002-2012 (n = 4792). These 4792 samples were analyzed for the presence of R. montanensis (n =  36; 2.84%) and all vector DNA was confirmed to be of D. variabilis origin using a novel Dermacentor genus-specific quantitative real-time polymerase chain reaction procedure, Derm, and a novel Dermacentor species multilocus sequence typing assay. To assess the risk of R. montanensis infection, the positive and negative samples were geographically mapped utilizing MTF site locations. Tick localities were imported into a geographical information systems (GIS) program, ArcGIS, for mapping and analysis. The ecological niche modeling (ENM) program, Maxent, was used to estimate the probability of tick presence in eastern United States using locations of both R. montanensis-positive and -negative ticks, climate, and elevation data. The ENM for R. montanensis-positive D. variabilis estimated high probabilities of the positive ticks occurring in two main areas, including the northern Midwest and mid-Atlantic portions of the northeastern regions of United States, whereas the R. montanensis-negative D. variabilis tick model showed a wider estimated range. The results suggest that R. montanensis-positive and -negative D. variabilis have different ranges where humans may be at risk and are influenced by similar and different factors. PMID:26900673

  16. Osteomielitis por salmonella

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    Alicia Velázquez Pérez

    2014-08-01

    Full Text Available Se presenta el caso de una paciente femenina de color blanco y dos años de edad, con diagnóstico prenatal de sicklemia, que desde edades tempranas tiene problemas de la enfermedad. Ingresó en esta ocasión por una de las complicaciones infecciosas que ocasiona este padecimiento, una osteomielitis del húmero izquierdo, aislándose el germen en el hemocultivo realizado, una salmonella. Necesitó de tratamiento enérgico y prolongado; se obtuvo un resultado satisfactorio en la evolución de la enfermedad y se sigue sistemáticamente por consulta externa en la actualidad

  17. Dermatitis canina por Malassezia

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    Rejas López, Juan

    2008-05-01

    Full Text Available La dermatitis por Malassezia en perros en generalmente una complicación a procesos alérgicos, seborreicos, presencia de pliegues, etc. aunque también se han descrito otras presentaciones, como la hipersensibilidad contra esta levadura. La demostración de la presencia de Malassesia pachydermatis se hace de manera sencilla mediante citología. El tratamiento de esta dermatitis puede ser tópico u oral.

  18. Dermatitis canina por Malassezia

    OpenAIRE

    Rejas López, Juan

    2008-01-01

    La dermatitis por Malassezia en perros en generalmente una complicación a procesos alérgicos, seborreicos, presencia de pliegues, etc. aunque también se han descrito otras presentaciones, como la hipersensibilidad contra esta levadura. La demostración de la presencia de Malassesia pachydermatis se hace de manera sencilla mediante citología. El tratamiento de esta dermatitis puede ser tópico u oral.

  19. causada por Fusarium moniliforme

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    Mariano Mendoza Elos

    2006-01-01

    Full Text Available El objetivo de éste trabajo fue determinar la resistencia horizontal de 134 líneas S1 de maíz al hongo Fusarium moniliforme. La enfermedad fue inducida mediante inoculación en la etapa de floración masculina bajo condiciones de campo utilizando la técnica del palillo. Las líneas se evaluaron en México en 2002. La estimación de la enfermedad se hizo en dos ocasiones con una separación de 20 días. Las evaluaciones mostraron que las líneas Roque-801, 804, 1103 y 1405 fueron resistentes en la primera evaluación. Las tasas de incremento de la enfermedad variaron de 0,01 a 0,229 por unidad por día. Las líneas mostraron bajos niveles de enfermedad de 0 a 1 % en la primera evaluación. En la segunda evaluación, los niveles de enfermedad variaron de 49 a 100 %. En un programa de mejoramiento genético estas líneas pueden ser utilizadas para mejorar la resistencia horizontal del maíz a la pudrición del tallo causada por Fusarium moniliforme

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

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    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.

  1. Prevalence of infection with Rickettsia helvetica in Ixodes ricinus ticks feeding on non-rickettsiemic rodent hosts in sylvatic habitats of west-central Poland.

    Science.gov (United States)

    Biernat, Beata; Stańczak, Joanna; Michalik, Jerzy; Sikora, Bożena; Wierzbicka, Anna

    2016-02-01

    Ixodes ricinus is the most prevalent and widely distributed tick species in European countries and plays a principal role in transmission of a wide range of microbial pathogens. It is also a main vector and reservoir of Rickettsia spp. of the spotted fever group with the infection level ranging in Poland from 1.3% to 11.4%. Nevertheless, little research has been conducted so far to identify reservoir hosts for these pathogens. A survey was undertaken to investigate the presence of Rickettsia spp. in wild small rodents and detached I. ricinus. Rodents, Apodemus flavicollis mice and Myodes glareolus voles were captured in typically sylvatic habitats of west-central Poland. Blood samples and collected ticks were analyzed by conventional, semi-nested and nested PCRs. Rickettsial species were determined by sequence analysis of obtained fragments of gltA and 16S rRNA genes. A total of 2339 immature I. ricinus (mostly larvae) were collected from 158 animals. Proportion of hosts carrying ticks was 84%, being higher for A. flavicollis than for M. glareolus. Rickettsia helvetica, the only species identified, was detected in 8% of 12 nymphs and in at least 10.7% (MIR) of 804 larvae investigated. Prevalence of infected ticks on both rodent species was comparable (10.8 vs. 9%). None of blood samples tested was positive for Rickettsia spp. The results showed that in sylvatic habitats the level of infestation with larval I. ricinus was higher in A. flavicollis mice in comparison with M. glareolus voles. They show that R. helvetica frequently occurred in ticks feeding on rodents. Positive immature ticks were collected from non-rickettsiemic hosts what might suggest a vertical route of their infection (transovarial and/or transstadial) or a very short-lasting rickettsiemia in rodents. A natural vertebrate reservoir host for R. helvetica remains to be determined.

  2. Miotoxicidade por organofosforados

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    Cavaliere Maria J.

    1996-01-01

    Full Text Available Os organofosforados são um grupo de compostos químicos amplamente utilizados em agropecuária como inseticidas, ocasionando intoxicações acidentais em animais e humanos, e mesmo sendo utilizados em tentativas de suicídio. A toxicidade desses produtos decorre sobretudo de insuficiência cárdio-respiratória por compromentimento do sistema nervoso autônomo. Sabe-se que alguns destes compostos induzem em animais de experimentação e em humanos, uma miopatia caracterizada por degeneração de células musculares, comprometendo sobretudo a musculatura respiratória. Baseado no fato de que este comprometimento contribui para a piora da função respiratória, propõe-se um protocolo de avaliação rotineira de miotoxicidade por compostos organofosforados, através de uma bateria mínima e suficiente de colorações e reações histoquímicas para quantificação da necrose muscular. Utilizaram-se como modelo experimental, grupos de ratos albinos (Wistar intoxicados com o organofosforado paraoxon, com e sem antídotos (atropina ou pralidoxima. Verificou-se nos grupos tratados com paraoxon e paraoxon mais atropina, necrose de fibras musculares no diafragma, que atingia em determinadas áreas até 15% das fibras. No grupo tratado com paraoxon mais pralidoxima, a necrose foi mínima, evidenciando o papel mioprotetor deste último antídoto.

  3. Por mil devaluados pesos

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    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  4. Rapid, simple, and sensitive detection of the ompB gene of spotted fever group rickettsiae by loop-mediated isothermal amplification

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    Pan Lei

    2012-10-01

    Full Text Available Abstract Background Spotted fever caused spotted fever group rickettsiae (SFGR is prevalent throughout China. In this study, we describe a rapid, simple, and sensitive loop-mediated isothermal amplification (LAMP assay targeting the ompB gene of spotted fever group rickettsiae ideal for application in China. The LAMP assay has the potential to detect spotted fever group rickettsiae early in infection and could therefore serve as an alternative to existing methods. Methods A set of universal primers which are specific 7 common species of spotted fever group rickettsiae in China were designed using PrimerExplorer V4 software based on conserved sequences of ompB gene. The sensitivity, specificity and reproducibility of the LAMP were evaluated. The LAMP assay for detecting SFGR was compared with conventional PCR assays for sensitivity and specificity in early phase blood samples obtained from 11 infected human subjects. Results The sensitivity of the LAMP assay was five copies per reaction (25 μL total volume, and the assay did not detect false-positive amplification across 42 strains of 27 members of the order Rickettsiales and 17 common clinical pathogens. The LAMP assay was negative to typhus group rickettsiae including R. prowazekii and R. typhi for no available conserved sequences of ompB was obtained for designing primers. To evaluate the clinical applicability of the LAMP assay, a total of 11 clinical samples, 10 samples confirmed serologically (3 cases, ecologically (1 case, by real-time polymerase chain reaction (PCR; 2 cases, ecologically and by real-time PCR (1 case, and serologically and by real-time PCR (3 cases were analyzed by the ompB LAMP assay. Data were validated using a previously established nested PCR protocol and real-time PCR. A positive LAMP result was obtained for 8 of the 10 confirmed cases (sensitivity, 73%; specificity, 100%, while none of these samples were positive by nested PCR (sensitivity, 0%; specificity, 100

  5. DETECTION OF RICKETTSIA FELIS LIKE AGENT FROM EULAELAPS STABULARIS KOCH%从厩真厉螨中检出与猫立克次体近缘的立克次体核酸片段

    Institute of Scientific and Technical Information of China (English)

    姚李四; 刘勇先; 邵丽筠; 张晓龙; 杨宇; 王静; 徐宝梁; 王宝麟; 赵彤言

    2012-01-01

    本研究用立克次体属特异的gltA和ompB基因扩增引物,从吉林长白县捕获鼠中分拣的534只厩真厉螨中扩得gltA和ompB基因片段.通过基因片段的序列测定、BLAST比对和系统发育分析,显示两个扩增基因与猫立克次体Rickettsia felis同源性最高(99%),证明该地区厩真厉螨携带与猫立克次体近缘的立克次体.%The segments of glt A gene and omp B gene were amplified and identified with Rickettsia specific git A and omp B primers from 534 mites (Eulaelaps stabularis Koch) collected from rodents of Changbai County, Jilin Province, China. By sequencing, BLAST qualifying and phylogenetic analyzing, it was revealed that the two amplified segments were of highest homology to Rickettsia fells (99% ) , implying that the locally collected E. Stabularis may carry some Rickettsia sp. Allied to Rickettsia fells.

  6. 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

  7. Primeiro caso de febre maculosa brasileira branda associada à artrite

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    Virgínia Lucia Nazario Bonoldi

    2014-06-01

    Full Text Available Descrevemos o primeiro caso brasileiro de Riquetsiose branda, agravada por monoartrite em joelho, em adulto jovem picado por carrapato na perna esquerda na região de Camburi, localizada no município de São Sebastião, sul da região costeira do estado de São Paulo, Mata Atlântica, Brasil. O paciente apresentou uma escara de inoculação no local da picada do carrapato, associada ao aumento ganglionar em virilha esquerda, febre, poliartralgia, cefaleia e erupção macular. Vinte dias após o episódio da picada de carrapato, o paciente apresentou monoartrite em joelho direito. O diagnóstico de Riquetsiose branda foi estabelecido pela análise imunológica sequencial em amostras de soro e líquido sinovial, tendo sido empregada a técnica de imunofluorescência (IF indireta para anticorpos reativos contra Rickettsia parkeri e Rickettsia rickettsii. A Riquetsiose branda é uma zoonose emergente, que deve ser investigada pelos médicos, incluindo reumatologistas, em pacientes que apresentem erupção macular, febre e, eventualmente, artrite, após visita ao sul da região costeira da Mata Atlântica no Brasil.

  8. Ojo por ojo

    OpenAIRE

    Ramón del Llano Ibáñez

    2011-01-01

    Nuestro pan y café de la mañana se acompaña de noticias alrededor de ejecuciones, de fosas clandestinas, de batallas del ejército, de balaceras en las calles y civiles caídos por balas perdidas : la muerte acompaña nuestro desayuno. Las calaveras de azúcar del día de muertos hoy son calaveras reales y amargas : 40 000 muertos en cuatro años después que el Presidente Calderón declaró la guerra a los narcotraficantes. Se han apresado a varios e importantes miembros de los cárteles : pero han si...

  9. Sepsis por shigella flexneri

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    César Cabrera C

    2005-04-01

    Full Text Available Se presenta un caso raro de sepsis por Shigella flexneri en una paciente de 45 años de edad quien estando hospitalizada para el estudio de un tumor cerebral, requirió el uso de manitol y dosis altas de corticoides; luego de ello presenta deposiciones líquidas con moco y sangre, desarrolla síndrome de respuesta inflamatoria sistémica, luego se aísla Shigella flexneri en el hemocultivo; recibió tratamiento antibiótico con ciprofloxacina. Se describen las características del caso y se comenta de acuerdo con la revisión de literatura.

  10. Onicomicosis por hongos fuliginosos

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    Ingrid Salas-Campos

    2009-12-01

    Full Text Available Justificación y objetivo: Las infecciones de las uñas producidas por hongos son un problema de frecuente consulta dermatológica. Los dermatofitos son la mayor causa de estas infecciones, siendo Trichophyton rubrum el agente etiológico más importante. Sin embargo, los hongos no dermatofitos, tanto hialinos como fuliginosos, pueden ser también responsables de estos cuadros clínicos. Debido a que estos hongos tienden a ser resistentes a los antimicóticos comúnmente usados para tratar las onicomicosis, es que se hace indispensable que el clínico se asegure por medio de un examen de laboratorio de la etiología de la infección. Métodos: Se estudiaron tres casos de pacientes con lesiones en uñas, que acudieron al laboratorio de Micología Médica, Facultad de Microbiología, Universidad de Costa Rica. Se realizaron los análisis de rutina para aislamiento e identificación de hongos patógenos. Resultados: En los tres casos estudiados se observó al examen directo micelio fuliginoso. En uno de los casos se aisló e identificó Scytalidium dimidiatum, hongo que presenta resistencia a los antifúngicos utilizados para tratar onicomicosis. Conclusión. El reporte de hongos diferentes a los dermatofitos como agentes etiológicos de onicomicosis es importante para que el médico pueda elegir el tratamiento más recomendado para este tipo de infección.

  11. Motivado por cirujanos

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    Carlos Salazar-Vargas

    2010-12-01

    Full Text Available Comenzaba la década de los 60 y nuestro grupo nerviosamente iniciaba lecciones en los hospitales de San José. En aquellos años, el estudiante de medicina empezaba su contacto con pacientes, por lo menos 1 ó 2 años después de iniciada la carrera. El estudio del ser humano normal que ya habíamos concluido, continuaba con el del enfermo, y más adelante aprenderíamos el tratamiento. La enfermedad descrita en el libro, de pronto se convertía en un enfermo, y es a este quien hoy veíamos, cohibido pero inquisidor, en la cama de un hospital. Los profesores nos enseñaban a interrogar y a examinar a los pacientes, y cada gesto suyo, cada pregunta, cada maniobra, eran celosamente guardados en la memoria de los educandos. Con claridad percibíamos, aun a temprana edad, las diferencias entre los especialistas, y casi de manera involuntaria, cada quien iba tomando partido y escogía su futuro camino. Fue durante esos tempranos años, cuando mi vida se cruzó con la de 7 maravillosas personas y excelentes cirujanos, que marcaron para siempre mi destino y, sin quererlo ellos, me hicieron inclinarme por la cirugía. Dos eran serios y profundamente académicos: el Dr. Manuel Aguilar Bonilla y el Dr. Vesalio Guzmán Calleja; 3, decididos, incansables y muy hábiles: el Dr. Longino Soto Pacheco, el Dr. Claudio Orlich Carranza y el Dr. Carlos Prada Díaz, y 2, abordables, prácticos, joviales y amistosos: el Dr. Fernando Valverde Soley y el Dr. Randall Ferris Iglesias….

  12. The Rickettsia prowazekii invasion gene homolog (invA) encodes a Nudix hydrolase active on adenosine (5')-pentaphospho-(5')-adenosine.

    Science.gov (United States)

    Gaywee, Jariyanart; Xu, WenLian; Radulovic, Suzana; Bessman, Maurice J; Azad, Abdu F

    2002-03-01

    The genomic sequence of Rickettsia prowazekii, the obligate intracellular bacterium responsible for epidemic typhus, reveals an uncharacterized invasion gene homolog (invA). The deduced protein of 18,752 Da contains a Nudix signature, the specific motif found in the Nudix hydrolase family. To characterize the function of InvA, the gene was cloned and overexpressed in Escherichia coli. The expressed protein was purified to near homogeneity and subsequently tested for its enzymatic activity against a series of nucleoside diphosphate derivatives. The purified InvA exhibits hydrolytic activity toward dinucleoside oligophosphates (Np(n)N; n > or = 5), a group of cellular signaling molecules. At optimal pH 8.5, the enzyme actively degrades adenosine (5')-pentaphospho-(5')-adenosine into ATP and ADP with a K(m) of 0.1 mM and k(cat) of 1.9 s(-1). Guanosine (5')-pentaphospho-(5')-guanosine and adenosine-(5')-hexaphospho (5')-adenosine are also substrates. Similar to other Nudix hydrolases, InvA requires a divalent metal cation, Mg(2+) or Zn(2+), for optimal activity. These data suggest that the rickettsial invasion protein likely plays a role in controlling the concentration of stress-induced dinucleoside oligophosphates following bacterial invasion.

  13. Sociedad por Acciones Simplificada

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Arcila Salazar

    2009-06-01

    Full Text Available En Colombia, aspectos como la responsabilidad limitada; supresión de la llamada doctrina de ultra vires; duración ilimitada; eliminación de la regla, una acción, un voto; remedios al abuso de los derechos; posibilidad de eliminar prohibiciones a los administradores, libertad de establecer restricciones para la transferencia de acciones y la simplificación de los procedimientos de fusión; son inviables bajo nuestra legislación. Sin embargo, la Ley 1258 de 2008, ha incorporado al derecho societario colombiano un nuevo tipo societario híbrido, llamado “Sociedad por Acciones Simplificada”. Esta forma societaria híbrida se basa en un principio básico: garantizar amplia libertad a los empresarios en la estructuración de sus relaciones a través de disposiciones contractuales. La S.A.S. provee a los empresarios significativa flexibilidad contractual, a la vez que preserva beneficios como la limitación de la responsabilidad.

  14. Sociedad por Acciones Simplificada

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Arcila Salazar

    2009-07-01

    Full Text Available En Colombia, aspectos como la responsabilidad limitada; supresión de la llamada doctrina de ultra vires; duración ilimitada; eliminación de la regla, una acción, un voto; remedios al abuso de los derechos; posibilidad de eliminar prohibiciones a los administradores, libertad de establecer restricciones para la transferencia de acciones y la simplificación de los procedimientos de fusión; son inviables bajo nuestra legislación. Sin embargo, la Ley 1258 de 2008, ha incorporado al derecho societario colombiano un nuevo tipo societario híbrido, llamado “Sociedad por Acciones Simplificada”. Esta forma societaria híbrida se basa en un principio básico: garantizar amplia libertad a los empresarios en la estructuración de sus relaciones a través de disposiciones contractuales. La S.A.S. provee a los empresarios significativa flexibilidad contractual, a la vez que preserva beneficios como la limitación de la responsabilidad.

  15. 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.

  16. Detection and identification of Rickettsia and rickettsial diseases%立克次体与立克次体病的检测与鉴定

    Institute of Scientific and Technical Information of China (English)

    张骁鹏; 李炘檑; 郑波; 胡晓梅

    2015-01-01

    立克次体是一类严格细胞内寄生的原核细胞型微生物,已被列入生物战剂名录。立克次体病是一类严重威胁人类健康的人兽共患的自然疫源性疾病。立克次体严格的细胞寄生性决定了立克次体病的诊断不同于传统方法,需根据流行病学资料、临床症状和体征及实验室检测进行综合判断,通常实验室检测是明确诊断的主要依据。从病原体的分离和培养到目前的基因水平比对,立克次体的检测技术虽发展了100多年,但人类尚未实现早期快速诊断立克次体病的目标。本文主要综述了立克次体与立克次体病检测与鉴定的研究进展。%Rickettsia is an obligate intracellular parasitic bacterium which has been included in the list of biowarfare agents .Rickettsial diseases are zoonotic ,natural focal diseases ,and also threats to human health seriously .Different from the standard detection methods for other bacteria , the diagnosis of rickettsial diseases needs a collective consideration of the epidemiological data ,clinical symptoms and laboratory test results .Although Rickettsia detection technology has been developed for more than 100 years ,early rapid diagnosis is still difficult . Current progresses on Rickettsia and rickettsial disease detection , including pathogen isolation and molecular detections ,are reviewed in this paper .

  17. 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.

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

    Science.gov (United States)

    Keating, M. Kelly; Spivey, Pamela; Lathrop, George W.; Powell, Nathaniel; Levin, Michael L.

    2016-01-01

    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 to identify a

  19. Por que sou rondoniano

    Directory of Open Access Journals (Sweden)

    Mércio Pereira Gomes

    2009-01-01

    Full Text Available Numa revisão contextualizada no tempo e projetada pelos seus resultados, a obra do sertanista marechal Cândido Rondon (1867-1958 é avaliada positivamente pela dedicação à causa dos povos indígenas do Brasil, pela formação de uma ética de respeito do brasileiro para com os índios e pela institucionalização do dever do Estado brasileiro de proteger, assistir e ajudar os povos indígenas a manterem-se coesos e autônomos e ao mesmo tempo se projetarem no mundo mais amplo. A vida de Rondon é acompanhada desde a sua formação como cadete da Escola Militar, como membro da Igreja do Apostolado Positivista, como comandante da Expedição Rondon (1907-1930, que levou o telégrafo de Cuiabá a Porto Velho, e especialmente como criador e dirigente-mor do Serviço de Proteção aos Índios (SPI, 1910-1967. Rondon é o criador da expressão "Morrer se preciso for, matar nunca", que pautou a ação de indigenistas brasileiros que fizeram os primeiros contatos com muitos povos indígenas desde 1910. E muitos morreram seguindo essa norma, numa clara demonstração do novo espírito humanista criado pela atitude rondoniana. O indigenismo brasileiro implantado por Rondon teve altos e baixos ao longo de quase cem anos, que hoje prossegue pela Fundação Nacional do Índio (Funai. De fato, muitos povos indígenas perderam suas terras e muitos foram dizimados no século XX, mas os mais de 220 que sobreviveram vêm crescendo em número, obtendo suas terras (13% do território nacional e conquistando novos espaços político-culturais no Brasil.This paper reviews the life and work of Brazilian Indianist Marshall Cândido Rondon. Rondon's life is marked by a profound dedication to the Brazilian Indian cause and to instilling in Brazilians a respect for Indian peoples. He influenced the Brazilian government in shaping a policy of protecting, assisting, and helping Indian peoples retain cohesive, self-determined societies. He also encouraged Indians to

  20. Respuesta de las neuronas sensitivas al estrés genotóxico inducido por radiaciones ionizantes y por la inhibición del proteasoma

    OpenAIRE

    Palanca Cuñado, Ana Rosa

    2014-01-01

    RESUMEN: Las neuronas son muy vulnerables al estrés genotóxico. Esta vulnerabilidad es particularmente relevante en las neuronas ganglionares sensitivas (NGS) dado que los ganglios carecen de barrera hematoencefálica que impida el acceso de agentes genotóxicos, como determinados fármacos utilizados en la quimioterapia del cáncer. Tales agentes producen un efecto neurotóxico que se traduce en neuropatías periféricas. Nuestro estudio analiza las bases celulares de la neurotoxicidad en las NGS e...

  1. Enhanced Expression of T-Cell Immunoglobulin and Mucin Domain Protein 3 in Endothelial Cells Facilitates Intracellular Killing of Rickettsia heilongjiangensis.

    Science.gov (United States)

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

    2016-01-01

    Rickettsia heilongjiangensis is the pathogen of Far eastern spotted fever, and T-cell immunoglobulin and mucin domain protein 3 (Tim-3) is expressed in human vascular endothelial cells, the major target cells of rickettsiae. In the present study, we investigated the effects of altered Tim-3 expression in vivo in mice and in vitro in human endothelial cells, on day 3 after R. heilongjiangensis infection. Compared with corresponding controls, rickettsial burdens both in vivo and in vitro were significantly higher with blocked Tim-3 signaling or silenced Tim-3 and significantly lower with overexpressed Tim-3. Additionally, the expression of inducible nitric oxide synthase and interferon γ in endothelial cells with blocked Tim-3 signaling or silenced Tim-3 was significantly lower, while the expression of inducible nitric oxide synthase, interferon γ, and tumor necrosis factor α in transgenic mice with Tim-3 overexpression was significantly higher. These results reveal that enhanced Tim-3 expression facilitates intracellular rickettsial killing in a nitric oxide-dependent manner in endothelial cells during the early phase of rickettsial infection.

  2. Porøse materialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2000-01-01

    Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

  3. Se los por se lo

    OpenAIRE

    José Luis Rivarola

    1985-01-01

    El sistema de la conjugación "objetiva" plantea interesantesproblemas que fueron tratados en parte por K. Heger (1966) en suestudio comparativo del francés y del español. De la comparaciónse desprende, por ejemplo, que en español hay un cierto número deambigüedades que no permiten establecer un "paradigma tan completo y unívoco" como en el caso del francés. Dentro de estas ambigüedades se encuentran las que propicia el gramema se: "El morfema [gramema] se funciona no sólo como pronombre refle...

  4. Ptose palpebral causada por Paquidermoperiostose

    Directory of Open Access Journals (Sweden)

    Patricia Regina de Pinho Tavares

    2014-08-01

    Full Text Available A paquidermoperiostose é uma síndrome caracterizada por acometimento cutâneo e ósseo, e em alguns casos ocorre comprometimento palpebral leve. É uma síndrome rara, idiopática ou hereditária, com provável herança autossômica dominante de penetrância variável. Descreve-se o caso de um paciente com ptose grave por paquidermoperiostose elucidando sua fisiopatologia e conduta cirúrgica aplicada.

  5. Molecular detection of spotted fever group rickettsia in Dermacentor silvarum from the Xunke Area,China%黑龙江逊克地区森林革蜱斑点热立克次体 DNA的检测

    Institute of Scientific and Technical Information of China (English)

    冯立; 王卓; 杨军; 于淼; 王立强; 邱广斌; 翟如波; 吴益民

    2014-01-01

    目的:调查黑龙江逊克地区蜱传斑点热自然疫源地,发现该地区蜱携带斑点热立克次体的种类。方法采用斑点热立克次体ompA和gltA 基因特异的PCR ,检测该地区森林革蜱的DNA样本,并对扩得阳性产物进行测序和聚类分析。结果从60只森林革蜱中检测有14只扩得斑点热立克次体ompA和gltA 基因片段,阳性率为23.33%。随机选择2只蜱的阳性片段进行测序,二者同源性为100%,ompA基因序列与Rickettsia sp .JL-02同源性为99.30%,与 Rickettsia raoultii为99.18%。结论黑龙江省逊克地区森林革蜱携带与 Rickettsia sp .JL-02株亲缘关系相近的斑点热群立克次体。%To identify the prevalence and the distribution of ticks infected with spotted fever group rickettsiae (SFGR) in Xunke Area of Heilongjiang Province ,China ,partial outer membrane protein A gene (ompA) and citrate synthase gene (gltA) specific fragments were assessed using the PCR method .The positive products were sequenced .Result showed that the pres-ence of SFGR was 14 of 60 in detection Dermacentor silvarum cases ,while the overall positive rate was 23 .33% .Its nucleotide sequence of ompA showed 99 .3% and 99 .18% similarity with nucleotide sequence of Rickettsia sp .JL-02 and Rickettsia rao-ultii respectively .And the evolutionary positions of SFGR species were similar with Rickettsiamontana and Rickettsiamassili-ae .It's concluded that the nature focus of tick-borne spotted fever did exist in the area of Xunke Area of Heilongjiang Province , China .

  6. Celulitis por citomegalovirus Cytomegalovirus cellulitis

    Directory of Open Access Journals (Sweden)

    A. Ruiz Lascano

    2002-12-01

    Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.Cutaneous lesions in CMV infection are rare, often a late manifestation of systemic infection, and usually herald a fatal course. A 70 year-old woman received a kidney transplantation one month before consulting and immunosuppressive therapy that included cyclosporine A and methylprednisone. She complained of fever, local pain in her right leg, and an erythematous and swelling plaque. She was treated with intravenous antibiotics without improvement. A skin biopsy was performed and the tissue obtained was sent for bacterial and fungal cultures as well as for histological examination. Cultures were negative. The biopsy showed CMV cytopathic changes. Immunoperoxidase staining was positive for CMV and polymerase chain reaction (PCR testing revealed CMV DNA. She was treated with ganciclovir with resolution of the lesion. CMV cellulitis is a rare cutaneous manifestation

  7. (phoenicopterus roseus por intoxicación aguda por plomo

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    D Romero

    2007-01-01

    Full Text Available La presencia de plomo en el medio ambiente es un hecho indiscutible. Ello es objeto de gran interés sanitario pues repercute tanto en la salud de los animales como en la del ser humano. El plumbismo es una intoxicación que puede afectar a cualquier especie animal. En el ámbito de la fauna silvestre se asocia principalmente a la actividad cinegética en los humedales y a la ingestión de plomo metálico por parte de las aves que frecuentan estos ecosistemas. En España cada año mueren decenas de miles de aves acuáticas como consecuencia de la ingesta de perdigones de plomo. En los individuos capturados enfermos se pueden observar signos clínicos, mientras que a partir de muestras de cadáveres se obtienen datos sobre niveles tisulares de plomo. Sin embargo la evaluación de lesiones anatomopatológicas en animales de vida silvestre es difícil de realizar por la dificultad de encontrar animales recién muertos o afectados de un cuadro agudo mortal. La reproducción de esta patología en animales de experimentación se suele realizar en cisnes, palomas o patos, pero no en flamencos, por lo que no es usual disponer de datos histológicos en esta especie. En este trabajo presentamos la clínica, analítica y estudio microscópico de diferentes tejidos de un flamenco común (Phoenicopterus roseus muerto por plumbismo.

  8. Síndrome de Frey por submaxilectomía y tratamiento con toxina botulínica Frey syndrome secondary to submaxillectomy and botulinic treatment

    Directory of Open Access Journals (Sweden)

    Alejandra Baéz

    2007-10-01

    Full Text Available El síndrome de Frey (SF se caracteriza por rubor, calor y sudación en la región maseterina y geniana durante las comidas. El SF se observa en el 20-60% de los pacientes sometidos a parotidectomía. Presentamos un caso con SF secundario a la ablación de la glándula submaxilar en un varón de 30 años de edad, sin antecedentes patológicos, que consultó en el año 2000 por adenopatía cervical izquierda. La misma fue biopsiada y la anatomía patológica informó carcinoma medular de tiroides. El paciente presentaba múltiples metástasis hepáticas y pulmonares, motivo por el cual recibió tratamiento quimioterápico con cisplatino plus doxorrubicina (seis ciclos con respuesta completa, finalizando dicho esquema en marzo del 2002. En julio del 2002 se realizó tiroidectomía total más vaciamiento ganglionar izquierdo con resección de la glándula submaxilar. Durante la cirugía se lesionó la rama mentoniana del nervio cervicofacial, rama del VII par craneal. En septiembre del 2004 consultó por episodios de sudación durante las comidas en la región submaxilar izquierda. Se realizó prueba de Minor y luego se procedió a aplicar toxina botulínica tipo A en la región afectada, a razón de 2.5 UI por punto (cm², a un total de 17 puntos. El control a los 21 días demostró más de un 95% de efectividad en la resolución del SF. El efecto duró un año, y una segunda reinfiltración mostró similar respuesta. No hallamos descripciones anteriores de SF en región submaxilar; se presenta su tratamiento satisfactorio con toxina botulínica tipo A.A case of Frey syndrome (FS secondary to submaxillar gland exeresis is presented and the results of the treatment with botulinum toxin (BTX type A. FS is a condition of sweating cheek and preauricular area during mealtime as a sequel detected in about 20-60% of patients after parotidectomy. The clinical symptoms include swelling, flushing and hyperhidrosis. The treatment choice for this condition is

  9. 中哈边境口岸臀突客蚤检出立克次氏体核酸%Rickettsia isolated from Xenopsylla minax at China-Kazakh border

    Institute of Scientific and Technical Information of China (English)

    罗丹; 尹小平; 王安东; 田延河; 梁臻; 巴特; 张江国

    2016-01-01

    目的 了解中哈边境地区臀突客蚤(Xenopsylla minax)中立克次氏体携带情况.方法 收集阿拉山口口岸臀突客蚤样本,PCR扩增立克次体17 kDa基因片段,PCR产物测序并BLAST比对,利用Mega 6.0构建分子遗传进化树.结果 42.86% (3/7)的臀突客蚤携带立克次体,17 kDa基因遗传进化树显示与Candidatus Rickettsia senegalensis和Rickettsia bellii同源性最高.结论 中哈边境口岸地区臀突客蚤携带立克次体核酸.

  10. Se los por se lo

    Directory of Open Access Journals (Sweden)

    José Luis Rivarola

    1985-12-01

    Full Text Available El sistema de la conjugación "objetiva" plantea interesantesproblemas que fueron tratados en parte por K. Heger (1966 en suestudio comparativo del francés y del español. De la comparaciónse desprende, por ejemplo, que en español hay un cierto número deambigüedades que no permiten establecer un "paradigma tan completo y unívoco" como en el caso del francés. Dentro de estas ambigüedades se encuentran las que propicia el gramema se: "El morfema [gramema] se funciona no sólo como pronombre reflexivo, sinotambién como variante combinatoria del pronombre personal complemento indirecto de la tercera persona.

  11. por el Tribunal Constitucional chileno

    Directory of Open Access Journals (Sweden)

    Marisol Peña Torres

    2008-01-01

    Full Text Available La modificación introducida por la reforma constitucional de agosto de 1989 al artículo 5º de la Constitución chilena sentó un criterio decisivo en la incorporación del derecho internacional de los derechos humanos al ordenamiento jurídico interno. El artículo examina la jurisprudencia del Tribunal Constitucional antes y después de esa reforma distinguiendo entre la aplicación del Derecho Internacional de los Derechos Humanos por haberse invocado en la acción deducida y la aplicación de principios y criterios hermenéuticos extraídos del mismo.

  12. Sepsis neonatal por Estreptococos Pyogenes

    Directory of Open Access Journals (Sweden)

    Gilberto Rodríguez-Herrera

    2009-09-01

    Full Text Available Se presenta el caso de un paciente masculino, recién nacido a término adecuado para la edad gestacional, quien nace por parto vaginal, con el antecedente de fiebre en la madre durante el periodo de postparto inmediato. Los padres consultan a los 2 días de vida pues le notan dificultad respiratoria, hipoactividad y rechazo a la leche materna. El paciente se interna y se aborda como una sepsis. Durante su estancia en el servicio de neonatología del Hospital Nacional de Niños asocia fallo respiratorio que amerita ventilación mecánica asistida por varios días en diferentes ocasiones, derrame pleural exudativo, convulsiones de origen hipóxico isquémico. Con reporte de hemocultivos positivos por Estreptococos pyogenes. El Estreptococos pyogenes o estreptococo β-hemolνtico del grupo A, fue un problema en los comienzos del siglo pasado, siendo frecuente en las infecciones puerperales y del reciιn nacido. En la actualidad es un germen sumamente raro en los procesos de sepsis neonatal.2 La gravedad de la enfermedad causada por este microorganismo en el periodo neonatal varνa desde una onfalitis crónica de bajo grado a una septicemia, una meningitis fulminante y la muerte.1 El presente artículo pretende hacer un resumen del paciente, con su evolución clínica, radiológica y además ejemplificar todas las complicaciones que tuvimos con este germen tan poco frecuente en la actualidad en sepsis neonatal.

  13. Study of the Five Rickettsia prowazekii Proteins Annotated as ATP/ADP Translocases (Tlc): Only Tlc1 Transports ATP/ADP, While Tlc4 and Tlc5 Transport Other Ribonucleotides

    OpenAIRE

    Audia, Jonathon P.; Winkler, Herbert H.

    2006-01-01

    The obligate intracytoplasmic pathogen Rickettsia prowazekii relies on the transport of many essential compounds from the cytoplasm of the eukaryotic host cell in lieu of de novo synthesis, an evolutionary outcome undoubtedly linked to obligatory growth in this metabolite-replete niche. The paradigm for the study of rickettsial transport systems is the ATP/ADP translocase Tlc1, which exchanges bacterial ADP for host cell ATP as a source of energy, rather than as a source of adenylate. Interes...

  14. Desajuste educativo por regiones en Colombia: ¿competencia por salarios o por puestos de trabajo?

    Directory of Open Access Journals (Sweden)

    Castillo Caicedo Maribel

    2007-08-01

    Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación,
    entendida como un desajuste por exceso, entre el nivel educativo alcanzado
    por el individuo y el exigido por el puesto de trabajo en el cual se
    desempeña; esto se debe a que existe una demanda laboral estrecha de
    puestos de trabajo para personas calificadas en Colombia. Se analizan las
    contribuciones empíricas existentes y el debate sobre las mismas; se
    examinan las teorías que permiten explicar la existencia de un desajuste
    educativo y se realiza una revisión de la literatura internacional y
    nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis
    para desarrollar un esquema que permita determinar el comportamiento
    del individuo en el fenómeno de la sobreeducación.

  15. 黑龙江立克次体感染血管内皮细胞的初步研究%Primary study on Rickettsia heilongjiangensis infection of vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    孟艳芬; 段长松; 王锡乐; 熊小路; 温博海

    2011-01-01

    The Rickettsia heilongjiangensis organisms purified by Renografin renografin gradient centrifugation were applied to infected human umbilical vein endothelial cells (HUVEC) grown in monolayer on cover slips. Rickettsiae were examined by both indirect immune fluorescence assay (IFA) and scanning electron micrograph (SEM) after rickettsial infection.During the first 24 hours postinfection (ip), two infection peaks were found at 6 and 24 hours pi, respectively. Multiplication of rickettsiae and pathological changes of host cells were observed at 5 days pi, while the amount of intracellular rickettsiae was markedly increased within 5 to 9 days pi. A few of rickettsiae were observed in the nucleus of host cells that appeared severe pathological changes within 8 to 9 days pi. Due to the overwhelming rickettsial infection, most of the infected host cells shed 12 days pi. Our results demonstrated that R. heilongjiangensis has a capability to infect vascular endothelial cells to cause vascular injury of humans.%目的 通过黑龙江立克次体感染体外培养人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVEC)探讨其在内皮细胞内的生长规律.方法 将泛影葡胺密度梯度超速离心纯化的黑龙江立克次体(HLJ-054株)感染体外培养的HUVEC,通过间接免疫荧光和扫描电镜检测与观察不同时相黑龙江立克次体在内皮细胞内的生长状况.热灭活黑龙江立克次体做平行对照.结果 立克次体粘附并侵入内皮细胞,在感染后第6 h及第24 h分别为感染高峰;感染5 d后细胞内立克次体逐渐增殖,第8~9 d细胞内立克次体急剧增殖,并见细胞核内有少量立克次体,细胞出现病变,第12 d细胞内充满立克次体,大部分细胞皱缩脱落.结论 黑龙江立克次体能够感染血管内皮细胞,在血管内皮细胞内不断增殖而使细胞死亡.

  16. 唐山地区蜱传斑点热群立克次体分子流行病学%Molecular epidemiological of spotted fever group Rickettsia from ticks in Tangshan area

    Institute of Scientific and Technical Information of China (English)

    邹亚学; 贾青辉; 刘朋朋; 刘全; 高宏伟; 陈丽凤

    2011-01-01

    Two sets of specific primers,designed according to 16SrRNA for tick and the OmpA gene specific for spotted fever group Rickettsia(SFGR),were used to amplify 16SrRNA and OmpA gene from DNA samples extracted from Haemaphysalis longicornis in Tangshan area.The positive samples were sequenced and genetically analyzed by establishment of phylogenetic tree.Of 315 samples,25 samples were positive for SFGR and the infection rate reached to 7.94%.Phylogenetic analysis based on nucleotide sequence revealed that all positive strains were related and clustered together with Rickettsia sp.Japanese strain(93.30%),Rickettsia sp.Fujian strain(92.11%),Rickettsia sp.suifen strain(90.45%) and Rickettsia sp.Hulin strain(90.42%).The infection of spotted fever group Rickettsia in Tangshan area was serious,and the bacterium may be a novel species.%根据已发表的长角血蜱16SrRNA序列及斑点热群立克次体外膜蛋白A(OmpA)基因序列设计2对特异性引物,对唐山地区采集的长角血蜱进行PCR检测,并对阳性样本进行测序和序列分析,抽检样本建立分子系统进化树。结果表明,在315份蜱DNA样本中检测出25份阳性样本,阳性率为7.94%;序列分析结果显示唐山地区长角血蜱携带立克次体同处于一个分支,与日本株立克次体同源性最高(93.30%),其次是福建株立克次体(92.11%),黑龙江立克次体绥芬株(90.45%)、虎林株(90.42%)。结论得出唐山地区蜱传斑点热感染较严重,分子进化分析结果显示唐山地区蜱传斑点热群立克次体可能为一新种。

  17. Clonagem de canistel por estaquia

    Directory of Open Access Journals (Sweden)

    Fernando Marcelo Chiamolera

    2014-09-01

    Full Text Available O canistel é nativo do sul do México e América Central e seus frutos apresentam elevado teor de carotenoides e vitamina A. Sua propagação é feita via sementes, resultando em considerável variabilidade genética entre os indivíduos, sendo a propagação vegetativa preferível, a fim de fixar características desejáveis. Assim, o objetivo deste trabalho foi avaliar a propagação vegetativa por estaquia de ramos semi-herbáceos de canistel, em função de quatro genótipos e quatro concentrações de AIB. Foram utilizadas estacas semiherbáceas apicais, mantidas com um par de folhas, sob nebulização intermitente, por 120 dias. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 4×4 (genótipos de canistel × concentrações de AIB, com quatro repetições e dez estacas por parcela. Foram avaliados a porcentagem de sobrevivência, a retenção foliar, o enraizamento, o calejamento, o número e o comprimento médio de raízes por estaca. O genótipo PC-1 foi superior aos demais, em todas as variáveis avaliadas, com destaque para o enraizamento das estacas, superior a 60%. As concentrações de AIB (0; 1.000; 3.000 e 5.000 mg L-1 não influenciaram na sobrevivência, retenção foliar e enraizamento das estacas, mas aumentaram o número e o comprimento de raízes em relação ao tratamento-controle (sem AIB. Há diferença na capacidade de enraizamento das estacas entre os genótipos de canistel, sendo a melhor resposta obtida com PC-1. A concentração de 3.000 mg L-1 de AIB resulta em maior número e comprimento de raízes nas estacas de canistel.

  18. Once mil metros por segundo

    OpenAIRE

    2012-01-01

    Esta exposición es una ventana hacia el mundo de la Ciencia Ficción. Los sueños de escritores extraordinarios, personajes, lugares, máquinas y robots que cada día están más cerca de nuestra cotidianidad gracias a los avances de la ciencia y la tecnología hacen parte de la muestra itinerante por las sedes de la Universidad Nacional. El visitante puede recorrer los diferentes géneros que constituyen este género literario, además de conocer sus principales representantes. Así mismo se explor...

  19. Sepsis neonatal por Estreptococos Pyogenes

    OpenAIRE

    Gilberto Rodríguez-Herrera; Cinthya Ramírez-Navarro

    2009-01-01

    Se presenta el caso de un paciente masculino, recién nacido a término adecuado para la edad gestacional, quien nace por parto vaginal, con el antecedente de fiebre en la madre durante el periodo de postparto inmediato. Los padres consultan a los 2 días de vida pues le notan dificultad respiratoria, hipoactividad y rechazo a la leche materna. El paciente se interna y se aborda como una sepsis. Durante su estancia en el servicio de neonatología del Hospital Nacional de Niños asocia fallo respir...

  20. Miasis ocular por Oestrus ovis

    Directory of Open Access Journals (Sweden)

    María Beltrán F

    2006-01-01

    Full Text Available Se presentan tres casos de miasis ocular (dos adultos y un niñoprocedentes de zonas ganaderas de la provincia de Huaura,departamento de Lima,que acudieron al Hospital Regional de Huacho por presentar el ojo rojo,fotofobia, edema palpebral y sensación de cuerpo extraño;se extrajeron larvas adheridas al canto interno del ojo,las cuales se recibieron en el Instituto Nacional de Salud y fueron identificadas como Oestrus ovis .

  1. Polioencefalomalacia experimental em bovinos induzida por toxicose por enxofre

    Directory of Open Access Journals (Sweden)

    Paulo H.J. Cunha

    2011-01-01

    Full Text Available O presente trabalho teve como objetivos avaliar os sinais clínicos, as concentrações do sulfeto de hidrogênio ruminal e as alterações anatomopatológicas associadas à intoxicação experimental por enxofre em bovinos. Foram utilizados dez bezerros mestiços leiteiros, sendo que quatro bovinos ingeriram ração sem sulfato de sódio (G1 e seis consumiram ração com sulfato de sódio (G2. Exames clínicos (temperatura retal, frequência cardíaca e respiratória e motricidade ruminal e laboratoriais (hemograma, fibrinogênio, proteína plasmática, pH do fluido ruminal, concentração do sulfeto de hidrogênio ruminal, líquido cerebrospinal e histopatológico foram realizados. A temperatura retal, frequência cardíaca, hemograma, fibrinogênio, proteína plasmática, pH do fluido ruminal e os valores do líquido cerebrospinal estavam dentro dos valores de referência para a espécie. Taquipnéia, hipomotricidade ruminal e elevados valores de sulfeto de hidrogênio ruminal foram observados nos bezerros do grupo G2. Um bezerro do grupo G2 apresentou sinais neurológicos e lesões histopatológicas de PEM. Dois animais de cada grupo foram eutanasiados. Lesões microscópicas foram observadas nos bezerros do G2. Histologicamente as alterações observadas foram necrose neuronal cortical e lesões hemorrágicas nos núcleos basais, tálamo, mesencéfalo, ponte e bulbo. O protocolo experimental constituído por uma dieta rica em carboidrato de alta fermentação, baixa quantidade de fibra efetiva e altos níveis de enxofre (0,52% ocasionou alterações clinicas e histológicas e elevadas concentrações de sulfeto de hidrogênio ruminal compatíveis com quadro de intoxicação por enxofre.

  2. toxicidad neuroendocrina inducida por cadmio

    Directory of Open Access Journals (Sweden)

    A Romero

    2008-01-01

    Full Text Available El cadmio es un agente químico tóxico importante debido a su creciente nivel en el medio ambiente como resultado de prácticas industriales y agrícolas. Como perturbador endocrino, el cadmio modifica la secreción de hormonas hipofisarias. Los efectos indirectos del cadmio provocan la generación de especies reactivas de oxígeno y reducen la actividad de las proteínas implicadas en las defensas antioxidantes. La melatonina es conocida como un potente antioxidante, scavenger de radicales libres y quelante de metales sintetizada en la glándula pineal. De esta manera, las acciones antioxidantes de esta indolamina protegen frente a la peroxidación lipídica y el daño oxidativo de los radicales y de sus productos tóxicos. Los trabajos recopilados en esta revisión ponen de manifiesto la capacidad antioxidante de la melatonina y, por lo tanto, su posible papel protector frente a la toxicidad del cadmio en lo que se refiere al estrés oxidativo y peroxidación lipídica inducidos por la exposición a este metal.

  3. Hipoglucemia inducida por carcinoma adrenal

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    Jimena Soutelo

    2013-08-01

    Full Text Available El carcinoma suprarrenal es una neoplasia maligna infrecuente y de mal pronóstico. La presentación clínica más común es originada por la producción hormonal excesiva, mientras que el desarrollo de hipoglucemia sintomática es excepcional. Presentamos el caso de una mujer de 37 años que ingresó al hospital por síntomas de hipoglucemias graves, hipertensión arterial, hipopotasemia y amenorrea secundaria. En el laboratorio se halló hipoglucemia con insulina inhibida y niveles de andrógenos en rango tumoral. La tomografía computarizada (TC de abdomen y pelvis mostró voluminosa formación heterogénea de aspecto sólido sin plano de clivaje con respecto al parénquima hepático e intenso realce con contraste. Luego de la extirpación de la masa retroperitoneal, evolucionó con valores de glucemia y potasemia normales, estabilizó la presión arterial y recuperó los ciclos menstruales.

  4. Studies on rickettsia-like organism(RLO)disease of tropical marine pearl oyster--Epidemiologicai investigation of RLO disease in juvenile populations of maricultured Pinctada maxima

    Institute of Scientific and Technical Information of China (English)

    Xinzhong Wu; Dengfeng Li; Jinpei Pan; Jingbo Jiang

    2003-01-01

    The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study andstatistic analyses, the epidemiological study was carried out on the disease and death in juvenile popula-tions of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A,B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farmof Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province fromNovember 1993 to April 1995. The results show that the deaths which occurred in juvenile populations of Pinctada maxima pre-sented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearloyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean bodylengths of juvenile populations show that the mortality rate become higher under 4 cm of mean bodylengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak ofmortality rate occurred in 1 ~3 cm of mean body lengths. The results of histological observation showedthat rickettsia-like organism inclusions were common, histological widespread infective agent among ev-ery batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rick-ettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile popula-tions. After or within every peaks of RLO infection were all accompanied with the peaks of mortalityrates of host populations and the mortality rates declined with decreased RLO infection. So the evidencesof histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO)may be as an important pathogenic organism of disease

  5. Mortalidad intrahospitalaria por accidente cerebrovascular

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    Federico Rodríguez Lucci

    2013-08-01

    Full Text Available La mortalidad global por accidente cerebrovascular (ACV ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Stroke de FLENI y los registros institucionales de mortalidad entre los años 2000 y 2010. Los subtipos de ACV isquémicos se clasificaron según criterios TOAST y los ACV hemorrágicos en hematomas intrapanquimatosos, hemorragias subaracnoideas aneurismáticas, malformaciones arteriovenosas y otros hematomas intraparenquimatosos. Se analizaron 1514 pacientes, 1079 (71% con ACV isquémico (grandes vasos 39%, cardioembólicos 27%, lacunares 9%, etiología indeterminada 14%, otras etiologías 11% y 435 (29% con ACV hemorrágico (intraparenquimatosos 27%, hemorragia subaracnoidea 30%, malformaciones arteriovenosas 25% y otros hematomas espontáneos 18%. Se registraron 38 muertes intrahospitalarias (17 ACV isquémicos y 21 ACV hemorrágicos, representando una mortalidad global del 2.5% (1.7% en ACV isquémicos y 4.8% en ACV hemorrágicos. No se registraron muertes asociadas al uso de fibrinolíticos endovenosos. La mortalidad intrahospitalaria en pacientes con ACV isquémico y hemorrágico en nuestro centro fue baja. El manejo en un centro dedicado a las enfermedades neurológicas y el enfoque multidisciplinario por personal médico y no médico entrenado en el cuidado de la enfermedad cerebrovascular podrían explicar, al menos en parte, estos resultados.

  6. Alterações oftálmicas associadas à intoxicação experimental por closantel em caprinos Ophthalmic changes associated with the experimental poisoning by closantel in caprine

    Directory of Open Access Journals (Sweden)

    R. Ecco

    2008-02-01

    Full Text Available Alterações oftálmicas foram experimentalmente induzidas em caprinos após superdosagem com o anti-helmíntico closantel. Foram usados cinco caprinos com sete a oito meses de idade, produtos do cruzamento da raça Saanen com a Pardo Alpino. Os animais mostraram sinais de intoxicação entre quatro e cinco dias após a administração do closantel. Os sinais clínicos caracterizaram-se principalmente por distúrbios neurológicos centrais e cegueira. Ao exame clínico, observaram-se midríase bilateral, perda do reflexo pupilar à luz e cegueira bilateral. À oftalmoscopia indireta, foram observadas degeneração aguda de retina e papiledema. As alterações crônicas mostravam disco óptico acinzentado, atrofia de vasos e da retina. Nos fundos tapetal e não-tapetal notavam-se áreas de despigmentação e lesões irregulares castanho-amareladas. As alterações histológicas consistiam em perda dos neurônios da camada ganglionar e das células da camada nuclear interna e externa da retina. As alterações agudas no nervo óptico e na substância branca do encéfalo foram de degeneração espongiforme. As alterações crônicas do nervo óptico caracterizavam-se por extensa necrose e infiltração de células Gitter.Ophthalmic alterations were experimentally induced after overdose with the anthelmintic closantel. Five seven to eight- months-old, Saanen x Alpine caprine were used. The animals showed clinical signs of toxicosis four to five days after the administration of closantel. Clinical signs were primarily characterized by central nervous disturbances and blindness. Clinically, bilateral mydriasis, loss of pupillary light reflex, and blindness were observed. At indirect ophthalmoscopic examination, there was acute retinal degeneration and papilledema. Chronic ocular changes consisted of paleness of the optic disc, vascular atrophy, and retinal atrophy. Areas of pigment loss and irregular yellowish-brown foci were present in the tapetal

  7. Detection of Rickettsia rickettsii in the tick Amblyomma cajennense in a new Brazilian spotted fever-endemic area in the state of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Elizângela Guedes

    2005-12-01

    Full Text Available The present study evaluated rickettsial infection in Amblyomma spp. ticks collected in a farm in Coronel Pacheco, a Brazilian spotted fever (BSF endemic area. A total of 78 A. cajennense and 78 A. dubitatum free-living adult ticks were collected and tested by polymerase chain reaction (PCR targeting a fragment of the rickettsial gene gltA. Only one pool of three A. cajennense ticks showed the expected product by PCR. This pool was further tested by PCR using sets of primers targeting the rickettsial genes gltA, ompA, and ompB. All reactions yielded the expected bands that by sequencing, showed 100% identity to the corresponding sequences of the Rickettsia rickettsii gene fragments gltA (1063-bp, ompA (457-bp, and ompB (720-bp. The minimal infection rate of R. rickettii in the A. cajennense population was 1.28% (at least one infected tick within 78 ticks.The present study showed molecular evidence for the presence of R. rickettsii in A. cajennense from a BSF-endemic area in Coronel Pacheco, state of Minas Gerais. Although R. rickettsii has been previously reported infecting A. cajennense ticks in Brazil and other Latin American countries, the present study performed the first molecular characterization of R. rickettsii from the tick A. cajennense.

  8. In vitro isolation and infection intensity of Rickettsia parkeri in Amblyomma triste ticks from the Paraná River Delta region, Argentina.

    Science.gov (United States)

    Monje, Lucas D; Nava, Santiago; Antoniazzi, Leandro R; Colombo, Valeria C; Beldomenico, Pablo M

    2014-10-01

    In the present study, we report the first in vitro isolation and infection intensity of Rickettsia parkeri in Amblyomma triste ticks from Argentina. No genetic differences in the molecular targets evaluated were found between R. parkeri isolates from Argentina and those R. parkeri isolates reported in Uruguay and Brazil, both obtained from A. triste. Only a minor difference was observed when compared to R. parkeri isolated from Amblyomma maculatum from United States. Moreover, the prevalence of infection by R. parkeri in ticks collected from the vegetation in the Paraná Delta was high (20.4%). Interestingly, the distribution of R. parkeri infection intensity observed in A. triste ticks was distinctly bimodal, with approximately 60% of the infected ticks presenting high rickettsial loads (3.8×10(5)-4.5×10(7) ompA copies/tick) and the remainder with low rickettsial levels (5.6×10(1)-6.5×10(3) ompA copies/tick). This bimodality in R. parkeri infection intensity in ticks could determine differences in the severity of the disease, but also be important for the infection dynamics of this pathogen. Further research exploring the distribution of rickettsial infection levels in ticks, as well as its determinants and implications, is warranted.

  9. Miotoxicidade por organofosforados Organophosphate myotoxicity

    Directory of Open Access Journals (Sweden)

    Maria J. Cavaliere

    1996-06-01

    Full Text Available Os organofosforados são um grupo de compostos químicos amplamente utilizados em agropecuária como inseticidas, ocasionando intoxicações acidentais em animais e humanos, e mesmo sendo utilizados em tentativas de suicídio. A toxicidade desses produtos decorre sobretudo de insuficiência cárdio-respiratória por compromentimento do sistema nervoso autônomo. Sabe-se que alguns destes compostos induzem em animais de experimentação e em humanos, uma miopatia caracterizada por degeneração de células musculares, comprometendo sobretudo a musculatura respiratória. Baseado no fato de que este comprometimento contribui para a piora da função respiratória, propõe-se um protocolo de avaliação rotineira de miotoxicidade por compostos organofosforados, através de uma bateria mínima e suficiente de colorações e reações histoquímicas para quantificação da necrose muscular. Utilizaram-se como modelo experimental, grupos de ratos albinos (Wistar intoxicados com o organofosforado paraoxon, com e sem antídotos (atropina ou pralidoxima. Verificou-se nos grupos tratados com paraoxon e paraoxon mais atropina, necrose de fibras musculares no diafragma, que atingia em determinadas áreas até 15% das fibras. No grupo tratado com paraoxon mais pralidoxima, a necrose foi mínima, evidenciando o papel mioprotetor deste último antídoto.Organophosphates comprise a group of chemical compounds extensively used in farming as insecticides, which cause accidental poisoning in animals and men and are also used in suicide attempts. The toxicity of these compounds is due especially to the cardiac and respiratory impairment in consequence of autonomic nervous system disorders. However, it is known that some of these products induce a myopathy in experimental animals and humans. This myopathy is characterized by muscle cell degeneration, involving above all the respiratory muscles. Based on the fact that this involvement certainly enhances the

  10. The detection of spotted fever group Rickettsia DNA from fever patients in Dali, Yunnan%云南省大理州发热患者血液中检测斑点热群立克次体

    Institute of Scientific and Technical Information of China (English)

    亚红祥; 王静林

    2012-01-01

    目的 调查云南省大理州不明原因发热患者是否存在斑点热.方法 用巢式-聚合酶链反应法扩增患者血液中的立克次体属groEL基因,并进行核酸序列鉴定和分析.结果 20例患者血液中检出1例立克次体核酸阳性(检出率5%),其序列分析与GenBank中Rickcttsia rickcttsii Iowa、Rickcttsia peacockii Rustic、Rickcttsia sibirica等斑点热群立克次体株的同源性最高(为99%).结论 首次证实云南大理地区存在斑点热患者,医疗部门应加强对斑点热的诊断与鉴别.%Objective To identify the pathogen of patients with fever with unknown origin and determine whether they were infected with spotted fever group Rickettsia. Methods Nested polymerase chain reaction (nPCR) was conducted to amplify groEL gene of rickettsia from the blood samples of the patients, the nucleotide sequencing and identification were carried out. Results Rickettsial DNA was detected in 1 of the 20 patients (5% ). The groEL gene of the strain shared high homology (99%) with Rickcttsia rickcttsii Iowa, Rickcttsia peacockii Rustic and Rickettsia sibirica. Conclusion It was the first time to diagnose the patient with spotted fever in Dali, Yunnan province. It is necessary to enhance the differential diagnosis of spotted fever in local medical institutions.

  11. 酿酒酵母线粒体蛋白转运系统在立克次体中的同源分析%The homology analysis of Saccharomyces cerevisiae mitochondrial protein import machinery in Rickettsia prowazekii

    Institute of Scientific and Technical Information of China (English)

    刘震; 李校; 赵培虎; 桂俊鸿; 张义正

    2011-01-01

    进化分析表明,与线粒体亲缘关系最近的原核生物是立克次体(Rickettsia prowazekii).搜索酿酒酵母(Saccharom ycescerevisia)线粒体蛋白转运系统的35个亚基在立克次体中的同源蛋白质,仅发现了5个同源蛋白,且它们只属于转运系统在线粒体外膜和基质上的模块,没有发现转运系统在膜间隙和内膜模块的同源蛋白.对大肠杆菌(Escherichia coli K-12 MG1655)的分析也有类似的结果.因此线粒体蛋白转运系统应该不是直接起源于内共生的原核生物.%ConA from 0 μg/mL to 100 μg/mL was added into Tca8113 cells, and MTT, cellular mor phology observation, LDH assay, flow cytometry detection and caspase assay were performed. MTT was applied to detect the inhibitory ratio of Tca8113 cells, and-morphologic changes, LDH, flow cytom etry detection were applied to detect apoptosis. In addition, caspase assy was also applied to observe whether caspase was involved in ConA-induced apoptosis in Tca8113 cells. After 24 h incubation with 25 μg/mL ConA, the inhibitory rate reached nearly 50%. Typical morphologic changes like membrane blebbing, chromatin condensation and nuclei fragmentation were confirmed. LDH assay and flow cytom etry detection showed that with the progressively increasing the concentration of ConA, more and more apoptotic cells appeared. And, caspase assay demonstrated that ConA could induce apoptosis in Tca8113 Phylogenetic analyses identified that Rickettsia prowazekii is the closest relatives of modern mitochondria. The homology analysis results from the 35 subunits of mitochondrial protein import mechanism of Saccharomyces cerevisiae, with thoce of Rickettsia prowazekii, suggest that only 5 sub units of the machinery have orthologous sequences from Rickettsia prowazekii. These 5 subunits are lo cated in the outer membrane and the matrix of mitochondria, while no subunit located in the inner mem brane and intermembrane space. Analysis of the Escherichia coli K

  12. 浙江省鼠形动物蜱源立克次体感染状况调查%A Cross-sectional study on tick-borne Rickettsiae infections among murine-like animals

    Institute of Scientific and Technical Information of China (English)

    柴程良; 陈恩富; 孙继民; 陆群英; 凌锋; 姜理平; 葛君华; 顾时平; 叶晓东; 刘社兰

    2014-01-01

    目的:了解浙江省不同类型地理环境中鼠形动物蜱源立克次体的感染状况。方法2009-2011年在安吉县、金东区和天台县用夹夜法捕获鼠形动物,进行分类鉴定、无菌采集肝脾标本,并采用巢式PCR方法检测无形体属与埃立克体属16SrRNA 以及立克次体属(包括斑疹伤寒群和斑点热群)与东方体属热休克蛋白基因groEL。结果3个调查点共捕获鼠形动物14种851头,社鼠(30.32%)、黑线姬鼠(18.80%)和青毛鼠(11.75%)为主要优势种,其中金东区、安吉县和天台县的优势鼠种分别为社鼠(39.20%)、青毛鼠(32.05%)和黑线姬鼠(59.57%)。562份肝脾标本中检出立克次体48份,阳性检出率为8.54%;其中无形体属占3.38%,斑疹伤寒群占1.78%,恙虫病东方体属占1.78%,埃立克体属占1.07%,斑点热群占0.53%。金东区和安吉县无形体属检出率较高为4.76%和4.27%,斑点热群仅在天台县检出。社鼠的立克次体阳性检出率最高为14.97%。同一鼠形动物可存在多种立克次体混合感染。结论浙江省不同类型地理环境鼠形动物中广泛存在立克次体感染,不同地理位?和不同鼠形动物的蜱源立克次体检出率不同。%Objective Toinvestigatethestatusoftick-borneRickettsiaeinfectionsamongmurine-likeanimalsin differentareasofZhejiangprovince.Methods Liverandspleensamplesofmurine-likeanimalscapturedthroughnight trapping method were collected from Anji,Jinhua and Tiantai County according to their geographic locations and historical detection of Rickettsiae .Nest-PCR tests were used to determine the presence of the 16S rRNA genes of Anaplasma and Ehrlichia ,and the heat shock protein genes (groEL)of Rickettsiae (including typhus and spotted fever group)and Orientiainthesesamples.Results Atotalof851murine-likeanimalsbelongingto14specieswerecaptured.The predominant species were Rattus confucianus (30

  13. La inconstitucionalidad por omisión

    Directory of Open Access Journals (Sweden)

    Luz Bulnes Aldunate

    2006-01-01

    Full Text Available El artículo analiza la facultad de los tribunales constitucionales para determinar la inconstitucionalidad por omisión, en virtud del silencio u omisión de la autoridad de normar un principio o regla constitucional dispuesto por la Constitución explícita o implícitamente.

  14. Verdad por definición

    Directory of Open Access Journals (Sweden)

    Garrido Garrido, Julián

    1997-07-01

    Full Text Available Not available.La verdad por definición es un tipo peculiar de verdad científica, distinguible de las verdades lógicas, matemáticas y empíricas. La definición, por su parte, designa diversos procedimientos de asignación de significado, cuyas diferencias exigen una adjetivación cuidadosa: definiciones ostensivas y operacionales, definiciones de diccionario y definiciones teóricas. Pero sólo las del último tipo son verdaderas por definición. En el presente artículo se precisa el concepto formal de definición teórica, se delimita la estructura de esos enunciados, se analiza la verdad por definición, y se comparan, por último, las definiciones teóricas con los otros tipos de definición.

  15. 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.

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

    Science.gov (United States)

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

    2016-07-01

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

  17. Liver Necrosis and Lethal Systemic Inflammation in a Murine Model of Rickettsia typhi Infection: Role of Neutrophils, Macrophages and NK Cells

    Science.gov (United States)

    Papp, Stefanie; Moderzynski, Kristin; Rauch, Jessica; Heine, Liza; Kuehl, Svenja; Richardt, Ulricke; Mueller, Heidelinde; Fleischer, Bernhard; Osterloh, Anke

    2016-01-01

    Rickettsia (R.) typhi is the causative agent of endemic typhus, an emerging febrile disease that is associated with complications such as pneumonia, encephalitis and liver dysfunction. To elucidate how innate immune mechanisms contribute to defense and pathology we here analyzed R. typhi infection of CB17 SCID mice that are congenic to BALB/c mice but lack adaptive immunity. CB17 SCID mice succumbed to R. typhi infection within 21 days and showed high bacterial load in spleen, brain, lung, and liver. Most evident pathological changes in R. typhi-infected CB17 SCID mice were massive liver necrosis and splenomegaly due to the disproportionate accumulation of neutrophils and macrophages (MΦ). Both neutrophils and MΦ infiltrated the liver and harbored R. typhi. Both cell populations expressed iNOS and produced reactive oxygen species (ROS) and, thus, exhibited an inflammatory and bactericidal phenotype. Surprisingly, depletion of neutrophils completely prevented liver necrosis but neither altered bacterial load nor protected CB17 SCID mice from death. Furthermore, the absence of neutrophils had no impact on the overwhelming systemic inflammatory response in these mice. This response was predominantly driven by activated MΦ and NK cells both of which expressed IFNγ and is considered as the reason of death. Finally, we observed that iNOS expression by MΦ and neutrophils did not correlate with R. typhi uptake in vivo. Moreover, we demonstrate that MΦ hardly respond to R. typhi in vitro. These findings indicate that R. typhi enters MΦ and also neutrophils unrecognized and that activation of these cells is mediated by other mechanisms in the context of tissue damage in vivo. PMID:27548618

  18. Evolution of NADPH-cytochrome P450 oxidoreductases (POR) in Apiales - POR 1 is missing

    DEFF Research Database (Denmark)

    Andersen, Trine Bundgaard; Hansen, Niels Bjørn; Laursen, Tomas;

    2016-01-01

    The NADPH-dependent cytochrome P450 oxidoreductase (POR) is the obligate electron donor to eukaryotic microsomal cytochromes P450 enzymes. The number of PORs within plant species is limited to one to four isoforms, with the most common being two PORs per plant. These enzymes provide electrons to ...

  19. Ixodid fauna and zoonotic agents in ticks from dogs: first report of Rickettsia rickettsii in Rhipicephalus sanguineus in the state of Mato Grosso do Sul, mid-western Brazil.

    Science.gov (United States)

    de Almeida, Robson Ferreira Cavalcante; Garcia, Marcos Valério; Cunha, Rodrigo Casquero; Matias, Jaqueline; e Silva, Elaine Araújo; de Fatima Cepa Matos, Maria; Andreotti, Renato

    2013-05-01

    Ticks from 148 dogs from the urban area of the municipality of Campo Grande, state of Mato Grosso do Sul, Brazil, were collected, classified and analyzed using polymerase chain reaction (PCR) for the identification of Rickettsia spp., Trypanosoma cruzi and Leishmania spp. A total of 2015 ticks were collected. The species Rhipicephalus sanguineus (98.9 %) and Amblyomma cajennense (1.1 %) were identified. Molecular analysis revealed that no tick samples were infected by T. cruzi. Regarding Leishmania spp., tick samples from 36 dogs spread across all regions of the municipality were positive for L. chagasi. One tick sample was positive for Rickettsia spp. (gltA gene) in the PCR reaction. This sample was submitted to further PCR based on the ompA gene and the amplicon was sequenced. Identity of 100 % was found with homologous sequences of R. rickettsii available in GenBank. This paper is the first to report the natural infection of R. sanguineus by R. rickettsii in the municipality of Campo Grande, state of Mato Grosso do Sul, mid-western Brazil.

  20. Molecular characteristics of emerging spotted fever group Rickettsiae and Anaplasma phagocytophilum in Hebei province, China%河北新发斑点热及人粒细胞无形体病实验室调查分析

    Institute of Scientific and Technical Information of China (English)

    孙印旗; 王勇; 姜霞; 姚娜; 钱振宇; 刘晓丽; 陈创夫; 张丽娟

    2015-01-01

    目的:对河北省新发蜱传斑点热群立克次体及人粒细胞无形体进行分子流行病学特征分析。方法对2009-2012年在河北省辛集、迁安及定州市收集的101份临床可疑立克次体病病例急性期血液DNA样本,采用2套巢氏PCR法分别扩增斑点热群立克次体热休克蛋白基因(groEL)和人粒细胞无形体16S rRNA基因并测序,序列采用NCBI网站进行Blast分析后,选择不同地区、不同宿主来源相应基因,使用DNAStar MegAlign同源分析。结果10.9%(11/101)的病例groEL扩增阳性,同源分析当地斑点热群立克次体groEL基因分为2个序列型,尽管有限片段无法区别立克次体种,但PCR阳性病例血清与我国常见黑龙江立克次体、西伯利亚立克次体、海南斑点热群立克次体及蚤传斑点热立克次体无抗原抗体反应,提示可能为新发斑点热。人粒细胞无形体16S rRNA基因扩增阳性率为8.9%(9/101),且病例急性期血清人粒细胞无形体IgM抗体全部阳性,其中3例急性期与恢复期血清发生IgG抗体转换。16S rRNA基因测序成功的9个序列(341 bp)100%同源,并且与该地区无形体病例分离株CZ-HGA-2100%同源。结论河北地区可能存在新发蜱传人粒细胞无形体病例及新发斑点热。加强立克次体实验室诊断及鉴别诊断、进一步开展病原学、相关媒介及宿主流行病学调查均具有重要的临床及公共卫生意义。%Objective To better understand the molecular epidemiological characteristics of emerging spotted fever group Rickettsiae and Anaplasma phagocytophilum identified in Hebei province. Methods One hundred and one clinical probable cases of typhus were collected from Xinji city, Qianan city and Dingzhou city, Hebei province during 2009-2012 and 101 acute stage and 17 convalescence blood samples were collected. Sera separated from blood were used for detecting the IgM and IgG antibodies against

  1. Verdad por definición

    OpenAIRE

    Garrido Garrido, Julián

    1997-01-01

    Not available.La verdad por definición es un tipo peculiar de verdad científica, distinguible de las verdades lógicas, matemáticas y empíricas. La definición, por su parte, designa diversos procedimientos de asignación de significado, cuyas diferencias exigen una adjetivación cuidadosa: definiciones ostensivas y operacionales, definiciones de diccionario y definiciones teóricas. Pero sólo las del último tipo son verdaderas por definición. En el presente artículo se precisa el concepto formal ...

  2. Molecular detection of rickettsias DNA in ticks around northeast region of China%东北部分地区蜱携带几种病原立克次体的分子检测

    Institute of Scientific and Technical Information of China (English)

    吴琼; 冯立; 王洪军; 吴益民; 付学奇; 王卓; 张志强

    2012-01-01

    Objective To understand the prevalence of tick-borne rickettsias around northeast region of China. Methods Wild ticks were captured and polymerase chain reaction (PCR) was used to amplify the rickettsias DNA of spotted fever group, human granulocytic ehrlichia and Ehrlichia chaff eensis carried by ticks. Results Ehrlichia chaff eensis DNA was found in I. Persulcatus and D. silvarum with the positive rates of 3.29% and 1.88% respectively. Meanwhile, human granulocytic ehrlichia DNA was amplified from I. Persulcatus with the positive rate of 2. 95%. However spotted fever group Rickettsiae was mainly found in H. concinna, with as high as 6.67% ticks carrying this rickettsiae, higher than that in I. Persulcatus and D. silvarum which were only 1. 69% and 2. 36%. Conclusions 7. Persulcatus and D. silvarum are possibly the main hosts of human granulocytic ehrlichia and Ehrlichia chaff eensis , while H. concinna mainly carries spotted fever group Rickettsiae in northeast region of China, indicating that it might be the natural foci of spotted feve, human granulocytic anaplasma and Ehrlichiosis.%目的 为了解东北地区蜱中携带立克次体的情况.方法 应用人工小时布旗法采集东北部分地区不同生境的游离蜱,采用PCR作斑点热立克次体、查菲埃立克体、人粒细胞无形体DNA检测.结果 从东北地区全沟硬蜱和森林革蜱检出查菲埃立克体DNA,全沟硬蜱平均阳性率为3.29%,森林革蜱为1.88%;从全沟硬蜱检出人粒细胞无形体DNA,平均阳性率为2.98%;从嗜群血蜱检出斑点热立克次体DNA,其平均阳性率(6.67%)明显高于全沟硬蜱(1.69%)和森林革蜱(2.36%).结论 东北地区全沟硬蜱和森林革蜱可能是查菲埃立克体、人粒细胞无形体的主要携带媒介,嗜群血蜱主要携带斑点热立克次体,提示东北地区存在三种蜱媒立克次体病的自然疫源地.

  3. Anticorpos anti-rickettsias do grupo da febre maculosa em equídeos e caninos no norte do Estado do Paraná, Brasil Anti rickettsia-antibody for spotted fever group in horses and dogs in the North of Paraná Stated, Brazil

    Directory of Open Access Journals (Sweden)

    F.H. Otomura

    2010-06-01

    Full Text Available The Brazilian Spotted Fever (BSF is a zoonosis that can be fatal if not trteated. As there are few studies of the BSF in the Paraná State, the occurrence of BSF was serologically investigated in dogs and horses by indirect immunofluorescence assay (IFA, in the North of that State, in animals that are regarded as sentinels for BSF. A total of 241 samples of sera of equine, four of asinine, and 29 of dogs were collected in nine farms of three municipalities in the North of Paraná: Arapongas, Douradina, and Umuarama. From fifteen samples of equine serum with positive titres for RIFI, eight (53.3 % had titre of 64 against R. rickettsii, two (13.3 % 128 against R. rickettsii, and five (33.3 % were reactants for R. parkeri and R. rickettsii, with titres ranging from 64 to 2048, and 128 to 1024, respectively. The results showed that domestic animals, sentinels for BSF, are under low exposition to ticks infected with spotted fever group Rickettsia, indicating low risk of human infection by these agents in the studied area.

  4. Intoxicación por Paraquat

    OpenAIRE

    Glenda Viales López

    2014-01-01

    El paraquat es un herbicida bipiridílico que actúa por contacto, se presenta en forma líquida en concentraciones del 20% para uso agrícola. Su nombre químico es eI 1-1´-dimetil-4-4- bipiridilo, con el nombre comercial de Gramoxone. La intoxicación por paraquat tiene una tasa de mortalidad elevada. La intoxicación grave se caracteriza por la afectación de múltiples órganos, principalmente los pulmones, los riñones y el hígado. El pulmón es el órgano diana en la intoxicación por paraquat y la i...

  5. 14 Nobel, preocupados por el CERN

    CERN Multimedia

    Rivera, A

    2003-01-01

    "E l presidente del Consejo del CERN (Laboratorio Europeo de Fisica de Particulas, junto a Ginebra), Maurice Bourquin, ha recibido una carta firmada por un grupo de cientificos muy especiales: 14 premios Nobel de Fisica" (1 page).

  6. Intoxicación por Paraquat

    Directory of Open Access Journals (Sweden)

    Glenda Viales López

    2014-12-01

    Full Text Available El paraquat es un herbicida bipiridílico que actúa por contacto, se presenta en forma líquida en concentraciones del 20% para uso agrícola. Su nombre químico es eI 1-1´-dimetil-4-4- bipiridilo, con el nombre comercial de Gramoxone. La intoxicación por paraquat tiene una tasa de mortalidad elevada. La intoxicación grave se caracteriza por la afectación de múltiples órganos, principalmente los pulmones, los riñones y el hígado. El pulmón es el órgano diana en la intoxicación por paraquat y la insuficiencia respiratoria con fibrosis pulmonar aguda es la causa más común de muerte.

  7. Micetoma por Nocardia brasiliensis: reporte de caso

    Directory of Open Access Journals (Sweden)

    Miriam Guevara R

    2003-07-01

    Full Text Available Se presenta el caso de un paciente peruano, agricultor, con una infección cutánea de origen traumático causada por Nocardia brasiliensis, que evolucionó hacia la amputación del miembro inferior afectado. El diagnóstico se realizó por examen directo y cultivo del espécimen.

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

    Science.gov (United States)

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

    2016-07-01

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

  9. Studies on rickettsia-like organism (RLO)disease of tropical marine pearl oyster--Epidemiological investigation of RLO disease in larvae populations of maricultured Pinctada maxima

    Institute of Scientific and Technical Information of China (English)

    Wu Xinzhong; Li Dengfeng; Pan Jinpei

    2001-01-01

    The epidemiological investigations on the disease and death in mature eggs, embryonic developmental periods and larvae populations [ including oocytes, fertilized ovum, early embryonic phase larvae (6 h), D- shaped phase larvae (24 h), early umbo phase larvae, umbo phase larvae, post umbo phase larvae and eyespot phase larvae] in the Luhuitou Pearl Oyster Mariculture Farm of Sanya City,Hainan Province in April 1995 showed that there were two peaks of mortality rates which occurred in early umbo phase or umbo phase and post umbo phase (Figs 3 ~ 5 and Table 1 ) respectively from preembryonic developmental periods to larvae phases. It indicated that the onset and death of Pinctada maxima larvae populations followed a pattern of outbreak. Between the prevalence, intensity of RLO infection and the mortality rates of larvae populations were of obvious positively correlations. Generally,every peak of RLO infection is always followed by a peak of mortality rate of larvae hosts, and the mortality rates of larvae hosts declined with the decreased RLO infection (see Figs 3~5). Under the transmission electron microscopy (TEM), no rickettsia-like organisms were discovered in oocytes, fertilized ovum and early embryonic phase larvae (6 h). The RLO inclusions occurred first in the D - shaped phase larvae (24 h) under histological examination. Absences of RLO in transmission electron examination of oocytes of RLO- infected adult females, fertilized ovum and early embryonic phase larvae (6h) indicated that RLO may not be transmitted transovarially. But RLO for host infection may be transmitted by contact transmission since RLO inclusions were first identified regularly in D - shaped phase larvae (24 h), while these D- shaped phase larvae were still unable to take food during hatching 24 hours. In addition, the result of epidemiological investigation showed that no observable death occurred in D- shaped larvae populations, but early obvious death occurred in larvae populations

  10. DNA microarray for simultaneous screening and detection of seven rickettsia%7种立克次体甄别检测基因芯片方法的建立

    Institute of Scientific and Technical Information of China (English)

    李灵云; 张英杰; 王升启; 刘琪琦

    2015-01-01

    目的:建立一种能同时检测7种立克次体的化学发光基因芯片法。方法根据NCBI公开发表的7种立克次体的序列设计引物和探针,制备立克次体甄别检测基因芯片。利用多重不对称PCR法扩增立克次体靶基因片段,标记的产物与基因芯片上的探针杂交,经清洗、化学发光显色后进行结果分析。在优化的多重PCR体系、杂交反应和化学发光检测条件下,评价芯片的特异性、灵敏度、重复性。用实时荧光PCR法与芯片法分别检测莫氏立克次体梯度稀释的核酸,比较两种方法的灵敏度。制备双盲模拟样本,进一步评价芯片方法的准确性。结果该研究共筛选出1对通用引物、4对特异性引物和1条立克次体属通用探针、9条特异性检测探针。该芯片检测质粒DNA的灵敏度为1.5×102~3×103拷贝/反应,检测模拟样本的灵敏度为103~104拷贝/μl。实时荧光PCR法与芯片法检测结果一致,实时荧光PCR法比芯片法灵敏度高10倍。双盲模拟样本检测符合率为100%。结论成功建立了可同时检测7种立克次体的化学发光基因芯片检测方法,为立克次体病的临床诊断和流行病学调查提供了一种新的高通量检测手段。%Objective To develop a chemiluminescence ( CL ) imaging DNA microarray method for simultaneous detection of seven rickettsiae.Methods Primers and probes were designed based on the specific sequence of seven rickettsia genomes.The probes were immobilized on the aldehyde modified glass surface to prepare DNA microarray for rickettsiae.The nucleic acids of the selected rickettsiae were amplified and labelled by multiplex PCR method, and then hybridized with microarray that was scanned after washing and chemiluminescence coloration, before the results were analyzed.Facilitated by the optimization of the multiplex PCR system, hybridization, and chemiluminescence imagination, we evaluated the

  11. Angiografia por tomografia computadorizada dos aneurismas intracranianos

    Directory of Open Access Journals (Sweden)

    Laureano Vinícius Santos

    2002-01-01

    Full Text Available Este trabalho foi realizado para avaliar os achados da angiografia por tomografia computadorizada, comparativamente à angiografia por subtração digital, em relação aos aneurismas intracranianos, e a possibilidade da maior utilização da angiografia por tomografia computadorizada no Brasil. Foram analisados oito pacientes que apresentavam um total de sete aneurismas não tratados e um aneurisma tratado. Houve subseqüente correlação com outros trabalhos publicados na literatura médica. Os exames foram realizados em uma clínica e em dois hospitais privados, na cidade do Rio de Janeiro, RJ. Foi demonstrada boa correlação entre os métodos estudados, em relação ao diagnóstico dos aneurismas, no acompanhamento e avaliação pré-terapêutica dessas lesões. A angiografia por tomografia computadorizada foi um exame menos invasivo, de menor custo e maior acessibilidade. Concluiu-se que a angiografia por tomografia computadorizada é um exame que deve ser utilizado com maior freqüência para avaliação nesta enfermidade.

  12. La conquista de Niebla por Alfonso X

    OpenAIRE

    García Sanjuán, Alejandro

    2000-01-01

    La conquista de Niebla en 660 H/1262 d.n.e. por el rey Alfonso X (1252-1284) puso fin a los cinco siglos y medio de Historia andalusí de dicha ciudad, largo período iniciado desde su sumisión por `Abd al- c Aziz b. Milsá en 94/713, al comienzo de la irrupción islámica en la Península Ibérica. Se trata, por lo tanto, de un episodio de gran relevancia en el devenir histórico de esta localidad, que ya desde época visigoda fue el principal núcleo urbano del territorio onubens...

  13. Neumopericardio debido a herida por arma blanca

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    Samuel I. Merino Barrera

    2015-10-01

    Full Text Available Hombre de 24 años de edad que ingresó en el hospital debido a una herida por arma blanca penetrante en el hemitórax derecho. La herida, de 3 cm a nivel de la piel, se localizaba a nivel del segundo espacio intercostal derecho y la radiografía de tórax demostró un neumotórax del mismo lado y una colección radiotransparente, por debajo del pericardio parietal, desde el origen de los grandes vasos hasta la porción apical del ventrículo izquierdo.

  14. Neumopericardio debido a herida por arma blanca

    OpenAIRE

    Samuel I. Merino Barrera; Francisco L. Moreno-Martínez

    2015-01-01

    Hombre de 24 años de edad que ingresó en el hospital debido a una herida por arma blanca penetrante en el hemitórax derecho. La herida, de 3 cm a nivel de la piel, se localizaba a nivel del segundo espacio intercostal derecho y la radiografía de tórax demostró un neumotórax del mismo lado y una colección radiotransparente, por debajo del pericardio parietal, desde el origen de los grandes vasos hasta la porción apical del ventrículo izquierdo.

  15. Endoftalmite por Candida albicans Candida albicans endophthalmitis

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    Pedro Duraes Serracarbassa

    2003-10-01

    Full Text Available O autor descreve os aspectos epidemiológicos, histopatológicos e clínicos da endoftalmite endógena por Candida albicans. Apresenta ainda novos métodos diagnósticos e opções terapêuticas utilizadas no tratamento das infecções fúngicas intra-oculares, por meio de revisão bibliográfica.The author describes epidemiological, histopathological and clinical aspects of endogenous Candida albicans endophthalmitis. He also presents new diagnostic methods and therapeutical options to treat intraocular fungal infections, based on literature review.

  16. PANORAMA LATINOAMERICANO DEL PAGO POR SERVICIOS AMBIENTALES

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    González T. Ángela

    2008-07-01

    Full Text Available Este documento busca proveer al lector de algunos elementos para el análisis y reflexión en torno al pago por servicios ambientales. Para ello, en primera instancia, aborda algunos conceptos básicos relacionados con economía ambiental, seguido de temas como la valoración económica de servicios ambientales y la implementación de mecanismos de pago por algunos de ellos. Lo anterior esta enriquecido con experiencias o estudios de caso a nivel latinoamericano y colombiano.

  17. Choque séptico por ehrliquiosis

    OpenAIRE

    Viviana Hernández-de Mezerville; Juan I Padilla-Cuadra

    2007-01-01

    La ehrliquiosis humana es una infección zoonótica transmitida por "garrapatas duras" causada por Anaplasma sp y Ehrlichia sp. Puede presentarse como un cuadro pseudogripal con fiebre, malestar general, mialgias y cefalea o hasta un choque séptico con falla multiorgánica y muerte. La mitad de los pacientes requieren atención hospitalaria en algún momento y se reporta una mortalidad de hasta el 5% secundaria a enfermedades oportunistas o a hemorragias. El diagnóstico se puede sospechar visualiz...

  18. Manejo conservador de una fistula de quilo por diseción radical de cuello: reporte de un caso y revisión de la literatura

    OpenAIRE

    E Brenes Leñero; M Murillo Ceciliano; E Mora Segura

    2015-01-01

    Se expone el caso de un paciente masculino de 59 años con diagnóstico de carcinoma medular de tiroides con metástasis ganglionares, al cual se le realiza una tiroidectomía total bilateral con disección radical de cuello modificada tipo III. En el postoperatorio se documenta fístula del conducto torácico. Se dio un manejo conservador con dieta hiperprotéica sin carbohidratos y rica en triglicéridos de cadena media el cual fue satisfactorio.

  19. Manejo conservador de una fistula de quilo por diseción radical de cuello: reporte de un caso y revisión de la literatura

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    E Brenes Leñero

    2015-12-01

    Full Text Available Se expone el caso de un paciente masculino de 59 años con diagnóstico de carcinoma medular de tiroides con metástasis ganglionares, al cual se le realiza una tiroidectomía total bilateral con disección radical de cuello modificada tipo III. En el postoperatorio se documenta fístula del conducto torácico. Se dio un manejo conservador con dieta hiperprotéica sin carbohidratos y rica en triglicéridos de cadena media el cual fue satisfactorio.

  20. 我国恙虫病立克次体(恙虫病东方体)分型研究近况%Advance research on serotype of patients with Rickettsia tsutsugamushi in China

    Institute of Scientific and Technical Information of China (English)

    郭恒彬

    2000-01-01

    @@ 恙虫病立克次体(Rickettsia tsutsugamushi,Rt)是恙虫病病原体,自从1931年定名以来,陆续发现Rt流行株,得到国际公认的有Gilliam,Karp,Kato,TA678,TA686,TA716,TA763和H1877 8个血清型[1],而Gilliam、Karp、Kato三型作为国际标准参照株.80年代初,日本[2]又分离到Kawasaki、Kuroki和Shimokoshi三型.在病原体的研究中,流行病学专家关注的问题,也就是病原体的分型,病原体的分型方法可分为表型分型和基因分型.有关Rt分型研究作简要叙述.

  1. Experimental Study on the Dynamic State of Rickettsia tsutsugamushi in Trombiculids%恙螨体内恙虫病立克次体动态变化的实验研究

    Institute of Scientific and Technical Information of China (English)

    郑小英; 黎家灿; 倪宏; 陈添胜; 陈成福

    1995-01-01

    应用PCR技术研究地里纤恙螨(Leptotrombidium deliense)实验感染恙虫病立克次体(Rickettsia tsutsugamushi)后恙螨体内立克次体DNA的动态变化.结果如下:立克次体在接种组成虫体内持续360天和经卵传递达4代;叮咬组饱食蚴体内立克次体经若蛹、若虫、成蛹达成虫期,成虫体内立克次体持续270天和经卵传递达2代,表明叮咬带立克次体鼠和经卵传递是保持恙螨亲代和子代体内立克次体动态循环的基础.

  2. 蜱斑点热群立克次体脱氧核糖核酸序列初步分析%Analysis of DNA sequences of spotted fever group rickettsia detected from ticks in Zhejing province

    Institute of Scientific and Technical Information of China (English)

    程苏云; 郑寿贵; 孟真; 叶晓东; 姜理平; 王志刚; 陆群英

    2010-01-01

    目的 了解浙江省媒介蜱斑点热群立克次体带菌状况.方法 通过扩增斑点热群立克次体外膜蛋白A基因片段,对浙江省金华市野兔、野猪寄生蜱标本进行检测分析.结果 对343份蜱标本分47组进行检测,分别从1组龟形花蜱和1组镰形扇头蜱中扩增出DNA阳性条带;经测序分析,分别命名为ZJ42和ZJ43株片段.ZJ42株与R.sp JL-95株关系较近,该株在外ompA的575~580位点有6个碱基(AAATAT)的插入缺失,可能是一个新菌株或种.ZJ43株与马赛立克次体、Rickettsia BAR-29和Rickettsia rhipicephali关系较近.结论 浙江省存在斑点热群立克次体的媒介蜱,应加强在媒介蜱,特别是镰形扇头蜱和龟形花蜱中对斑点热群立克次体的监测,并研究它们的致病性.

  3. Analgesia caudal continua guiada por ultrasonido en una paciente de 4 años Caudal anesthesia ultrasound-guided continuos flow in patient 4 years

    Directory of Open Access Journals (Sweden)

    A. Beltrán Franco

    2013-02-01

    Full Text Available La epidural caudal es la técnica más popular en anestesia y analgesia regional pediátrica. El empleo de una guía ecográfica en este procedimiento, aunque aún no es un estándar, podría disminuir los riesgos inherentes a la técnica tradicional y ofrecer algunas ventajas. Nosotros describimos el caso de una niña de 4 años sometida a una resección de un rabdomiosarcoma en muslo izquierdo con metástasis ganglionar inguinal e implantación de catéteres para braquiterapia; a quien se le colocó un catéter caudal para analgesia postoperatoria continua, usando la ultrasonografía (US como método para guiar la colocación de dicho catéter. Después de inducir anestesia general, se realizó un escaneo ecográfico previo de la zona sacra identificando la anatomía, posteriormente después de implementar las medidas antisépticas y asépticas se colocó un catéter caudal guiado por US en tiempo real y con modo Doppler color se confirmó la posición en el espacio epidural caudal al inyectar una dosis en bolo de mezcla anestésica. Se presentó un adecuado control del dolor postoperatorio. El uso de US es una excelente alternativa a las técnicas clásicas fundamentadas en anatomía para la inserción de catéteres epidurales continuos en pediatría y permite ciertas ventajas que las técnicas a ciegas no pueden brindar.Caudal epidural is the most popular regional analgesia and anesthesia technique in pediatrics. The use of ultrasound (US guidance in this procedure, is not yet the standard, but could reduce the risks related with the traditional approach and offer some advantages. We described a case of a 4-years-old patient undergoing a resection of a rabdomyosarcome on the left thigh plus inguinal metastatic nodes and implantation of brachitherapy catheters, in whom a continous caudal epidural catheter was placed under US guidance. After general anesthesia induction, a scout scanning identified the anatomy and afterwards, using strict

  4. Pedro Teixeira y su viaje por Mesopotamia

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    Fuente del Pilar, José Javier

    2005-04-01

    Full Text Available Pedro Teixeira es un integrante notable de la ilustre nómina de los viajeros portugueses que, a finales del s, XVI y principios del XVII, ensancharon para Occidente las fronteras del mundo. Su conocimiento en España se debe a la publicación en 1994 de su obra «Relaciones del Origen, Descendencia y Sucesión de los Reyes de Persia, y de Harmuz, y de un viaje hecho por el autor dende la India hasta Italia por tierra», en edición realizada por el profesor Eduardo Barajas Sala, lamentablemente fallecido en 1997. En este artículo se ofrece una reseña biográfica de Pedro Teixeira, y un análisis del viaje narrado por el autor en la última parte de sus «Relaciones »: el que desde Ormuz le conducirá, a través de Mesopotamia, hasta la costa del Mediterráneo.…

  5. Dermatoses provocadas por plantas (fitodermatoses Dermatosis due to plants (phytodermatosis

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    Vitor Manoel Silva dos Reis

    2010-08-01

    Full Text Available As dermatoses causadas por plantas são relativamente comuns no nosso meio e podem ocorrer por diversos mecanismos patogênicos. São descritas dermatoses por trauma físico, por ação farmacológica, mediadas por IgE, por irritação, por ação conjunta da luz e por sensibilização. Também são descritas na introdução desta revisão as pseudofitodermatoses causadas por elementos veiculados pelas plantas e, por isso, aparentemente causadas pelas plantas.Dermatosis caused by plants is relatively common and may occur by various pathogenic mechanisms. Dermatitis due to physical trauma, pharmacological action, irritation, sensitization, mediated by IgE and induced by light are described. Pseudophytodermatosis caused by plant-delivered elements is also described in the introduction to this work.

  6. Control de la conducta inducida por programa por sus consecuencias ambientales

    OpenAIRE

    Ardoy Cuadros, Juan

    2008-01-01

    La presente Tesis Doctoral se ha desarrollado dentro de una de las líneas de investigación desarrollada por el Departamento de Psicología Básica I de la UNED y cuyo objetivo prioritario es el estudio de las características de la conducta inducida por programa, así como el control ambiental y farmacológico de la misma. El objetivo de esta investigación, en concreto, es determinar los factores implicados en la aparición de la polidipsia inducida por programa en ratas, así como en su mantenimi...

  7. Cross-sectional survey on the prevalence of antibodies to several types of Rickettsia in human and livestock in Jiangsu province%江苏省几种主要类型人畜立克次体抗体阳性检出情况的现况调查

    Institute of Scientific and Technical Information of China (English)

    谭兆营; 李亮; 张丽娟

    2012-01-01

    Objective To investigate the main types of Rickettsia infection, prevalence of antibodies to Rickettsia and associated factors among human and livestock in Jiangsu province. Methods Five survey sites in different areas in the Province, e. g. Lishui, Peixian, Xuyi, Yixing and Binhai, were selected. Indirect immunofluorescence was applied to detect antibody IgG and IgM to seven common types of Rickettsia such as Rickettsia mooseri ( RM ) , Rickettsia heilongjiangii ( RH ) , R. tsutsugamushi, Coxiella burnetii ( CB ), Bartonella henselae/Bartonella quintana ( BH/BQ ) , Ehrlichia chaffeeusis ( MME ) and Human granulocytic anaplasmosis(HGA). Results The prevalence of BH/BQ infection was the highest in 2 562 sera in the five survey sites (24. 8% ). Prevalence of antibodies was higher in women than that in men, except prevalence of antibodies to HGA and BH/BQ, which was higher in men than that in women. Regional difference was found in all Rickettsia infections except RH/RS. Antibodies to seven types of zoonotic Rickettsia were all detected in animals. The prevalence of OT infection was the highest (31.8%). It mainly infected goats and the prevalence was different in various areas. Multivariate analysis indicated that age, sex, area and history of tick/mite bite were associated with the prevalence. Conclusions Several types of Rickettsia infection were prevalent in farming population and livestock in Jiangsu province. Infections by RM, BH/BQ and CB were dominant.%目的 了解江苏省人畜立克次体感染的主要类型、抗体阳性检出率及感染的可能影响因素.方法 按地理位置,选择江苏省溧水县、沛县、盱眙县、宜兴市和滨海县的5个调查点,采用间接免疫荧光法检测莫氏立克次体(RM)、黑龙江立克次体/西伯利亚立克次体(RH/RS)、恙虫病东方体(OT)、贝氏柯克斯体(CB)、横赛巴尔通体/五日热巴尔通体(BH/BQ)、查菲埃立克体(HME)及人粒细胞无形体(HGA)等7种常见立克次

  8. Responsabilidad penal del empleador por delitos cometidos en la empresa por sus subordinados

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    Walter Jose Saavedra Troncoso

    2013-07-01

    Full Text Available En este trabajo se realiza un estudio sobre la responsabilidad penal del empresario por los actos al margen de la ley que cometen sus subordinados. Se busca aclarar si el empresario debe responder penalmente cuando el delito es cometido por un subordinado en ejercicio de sus funciones o cuando este actúa a nombre de la empresa ya sea valiéndose de la información que manejan, del grado de responsabilidad o de la confianza. Por esta razón concentraremos nuestra atención en analizar la responsabilidad penal por la omisión de controles del empresario hacia el subordinado, exponiendo la problemática que se deriva de la posición de garante del primero en las operaciones empresariales.

  9. DIATERMIA POR ONDAS CURTAS: ANÁLISE DA TEMPERATURA CORPORAL SUPERFICIAL POR TERMOGRAFIA

    OpenAIRE

    Sergio Fernando Zavarize; Anderson Martelli; Samara Aparecida Machado; Estela Maria Correia Sant’Ana

    2014-01-01

    Introdução: Poucos estudos relacionam os efeitos da diatermia por ondas curtas (DOC) e a área de aquecimento promovido por sua aplicação. Objetivo: O objetivo do trabalho foi avaliar o comportamento da temperatura superficial corporal antes e após a aplicação de DOC por meio da termografia cutânea. Materiais e métodos: A análise da temperatura corporal no local da aplicação foi realizada através da captura da imagem por meio de câmera termográfica após quinze minutos de repouso do...

  10. Responsabilidad por violación de la buena fe en la sociedad por acciones simplificada

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    Nicolás Polanía Tello

    2012-12-01

    Full Text Available La sociedad por acciones simplificada –SAS–, como los demás esquemas societarios, se funda en y está informada por el principio de la buena fe. Pero a diferencia de los otros modelos, la SAS tiene concreciones particulares de la buena fe que permiten un amparo más efectivo y eficiente de los derechos de los socios y de los terceros, en la medida en que instituciones como el fraude a la ley, el perjuicio injusto a terceros, el abuso del derecho y el administrador de hecho, todos estructurados a partir de violaciones a la buena fe, permiten tramitar los eventos de responsabilidad por ilícitos atípicos y llegar incluso a desestimar por ello el atributo de la limitación de responsabilidad.

  11. Muestreo por conglomerados en encuestas poblacionales

    OpenAIRE

    Zapata-Ossa, Helmer de Jesús; Angela M Cubides-Munévar; María C. López; Pinzón-Gómez, Elisa M.; Filigrana-Villegas, Paola A.; Cassiani-Miranda, Carlos A.

    2012-01-01

    Objetivo Describir la técnica estadística del muestreo por conglomerados en encuestas de salud poblacionales. Métodos Se describen los aspectos más importantes de cada uno de los pasos metodológicos   haciendo énfasis en los fundamentos del Muestreo por Conglomerados. Éste se aplicó sobre una población  de aproximadamente 100 000 habitantes de la comuna 18 de Cali. La muestra abarcó 30 manzanas y se encuestaron 3 026 personas. La información se recolectó usando el Sistema de Información de ba...

  12. Tomate industrial con riego por cinta

    OpenAIRE

    Adán Fimbres-Fontes

    2004-01-01

    La región agrícola de Caborca cuenta con una superficie de 40 000 ha, las cuales se riegan con agua proveniente de aproximadamente 700 pozos. El abatimiento del manto acuífero es, en promedio, de 0.82 m año-1 y, en 25 años, ha sido de 20.50 m, medidos al nivel estático. El agua es uno de los factores más importantes en la producción de cualquier cultivo en la región. El objetivo del presente trabajo fue optimizar la cantidad de agua por aplicar al tomate industrial cultivado con riego por cin...

  13. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

  14. Celulitis por cuerpo extraño

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    Miguel B. Carrasco Guzmán

    2016-01-01

    Full Text Available Las infecciones de la piel y el tejido celular subcutáneo surgen como un grupo importante de afecciones con una alta morbilidad en edades pediátricas, generalmente relacionada con traumatismo y cuerpos extraños. Se presenta el caso de una escolar femenina de 6 años de edad, con síntomas y signos clínicos que sugieren celulitis en el muslo derecho,  por su evolución tórpida se le realizó el estudio ultrasonográfico que confirmó el diagnóstico etiológico de una celulitis secundaria a un traumatismo, provocada por la introducción de un gran cuerpo extraño, que pasó inadvertido para a familia de la menor.

  15. Doença da arranhadura do gato por Bartonella quintana em lactente: uma apresentação incomum

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    Azevedo Zina Maria Almeida de

    2000-01-01

    Full Text Available Relato de caso de doença da arranhadura do gato (DAG, em um paciente lactente, com história epidemiológica negativa, descrevendo o rastreamento diagnóstico, a imagem ao ultra-som, a evolução clínica e o prognóstico. B. quintana foi identificada em aspirado de secreção ganglionar pelo método de PCR. B. henselae, embora seja o agente causal habitualmente responsável pela DAG, não foi isolada. Os autores concluem que a pesquisa de B. quintana e B. henselae deve ser incluída na investigação de adenites, principalmente quando a evolução é subaguda, mesmo em lactentes e, ainda que a história epidemiológica seja negativa.

  16. sobrevida de ratas intoxicadas por paraquat

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    Y. Aular

    2005-01-01

    Full Text Available La vitamina C (VC y la trimetazidina (TMZ como antioxidantes y la posible acción intiinflamatoria de esta última podrían ser de utilidad en la intoxicación por paraquat. Por tal razón se decidió evaluar el efecto de esta asociación en los niveles de VC, peso y sobrevida de ratas intoxicadas por paraquat, para ello se diseñó un estudio con 56 ratas divididas en 8 grupos: A (control negativo; B (control positivo, recibieron 11 mg/Kg. de paraquat IP; C (pre tratadas con 28.5mg/Kg. VC oral; D (tratadas con 28.5mg/Kg. VC post intoxicación; E (pre tratadas con 5mg/Kg. TMZ oral; F (tratadas con 5mg/Kg. TMZ post intoxicación; G (pre tratadas con VC- TMZ; H (tratadas con VC- TMZ post intoxicación. Se determinaron niveles de VC, cambios de peso y sobrevida en los grupos experimentales durante 31 días. Los resultados mostraron el día 24 de experimentación: disminución de los niveles de VC en el grupo E (p<0.05 y aumento en el grupo G (p< 0.001, sobrevida de 62.5% (grupo G, 50% (grupos E y H y 25% (grupos C y D. Se concluye que la asociación VC- TMZ aumentó la sobrevida de ratas intoxicadas por paraquat

  17. Intoxicación por drogas

    Directory of Open Access Journals (Sweden)

    I. Gainza

    2003-01-01

    Full Text Available El consumo de drogas ilegales en nuestro país ha experimentado un notable cambio en los últimos años, relegando a la heroína e incorporando la cocaína, los derivados anfetamínicos como el "éxtasis" (MDMA, el "éxtasis líquido" (GHB y, en menor medida, la ketamina. Se lleva a cabo una revisión de la intoxicación aguda por opiáceos y de su tratamiento en los servicios de urgencias, teniendo en cuenta el descenso progresivo de los casos que se presentan con el advenimiento de nuevas formas de administración, así como la presencia de nuevas drogas adictivas que han dado lugar a un desplazamiento en los hábitos de consumo. Se expone la intoxicación por cocaína haciendo referencia a la clínica, el diagnóstico y el tratamiento. Se realiza una revisión sobre el cannabis y sus derivados, la historia de su consumo y preparaciones utilizadas, los efectos que producen en los distintos sistemas del organismo y sus principales mecanismos de acción. Por último se comentan los efectos del LSD y de las setas alucinógenas.

  18. Intoxicación aguda por plaguicidas

    Directory of Open Access Journals (Sweden)

    Durán-Nah Jaime Jesús

    2000-01-01

    Full Text Available OBJETIVO: Describir la epidemiología de la intoxicación aguda por plaguicidas (IAP en el Hospital General O'Horán de Mérida, Yucatán, México. MATERIAL Y MÉTODOS: Se revisaron los expedientes de 33 pacientes superscript three 13 años, tratados en una unidad de cuidados intensivos (UCI, entre 1994 y 1998. Se recopilaron variables demográficas y clínicas relevantes, y se aplicó estadística descriptiva. RESULTADOS: En la población estudiada predominó el sexo masculino (82% del medio rural (70%, y la edad media fue de 34 ± 15.8 años. El intento de suicidio fue causa frecuente de IAP (79%, y en 33% de los casos la intoxicación se produjo por la utilización de organofosforados. La mortalidad fue de 12%. CONCLUSIONES: La IAP fue baja entre los sujetos del medio rural, por lo que los resultados de este estudio parecen no reflejar la realidad del problema. Es importante añadir que los plaguicidas son utilizados con relativa frecuencia para el intento de suicidio.

  19. Leibniz damnificado por el terremoto de Lisboa

    Directory of Open Access Journals (Sweden)

    Evaristo ÁLVAREZ MUÑOZ

    2009-11-01

    Full Text Available RESUMEN: En las páginas que siguen se argumenta que al filósofo alemán Gottfried Wilhelm Leibniz —fallecido en Hannover en 1716— o, al menos, a su obra Teodicea, cabría contarlos, echadas las cuentas de la manera que se verá, entre las víctimas del terremoto de Lisboa de 1755. Asimismo se subraya la persistencia del pensamiento de Leibniz en las respuestas dadas por los filósofos del siglo XVIII al trágico suceso. Se estudian las reacciones de Voltaire, de Rousseau y de Kant ante los estragos provocados por el seísmo y se concluye que las manifestaciones de los dos primeros ya habían sido previstas en Teodicea e, incluso, la vía científica pretendida por Kant había sido abierta en Protogaea.ABSTRACT: It is argued here that German philosopher Gottfried Wilhelm Leibniz, passed away in 1716, and, specially, that his work Teodicea, could be considered amongst the victims of the Lisbon earthquake of 1755. The persistence of the Leibniz’s thought in the answers given by the philosophers of the 18th Century to the tragic event is also emphasized. Voltaire and Rousseau’s reactions to the damage caused by the earthquake had been anticipated in Teodicea and the scientific way followed by Kant had been initiated in Protogaea.

  20. Por un humor ético

    Directory of Open Access Journals (Sweden)

    Victor Paramo Valero

    2016-04-01

    Full Text Available Ética del humor es una obra original, abundantemente documentada, de contenido científico y filosófico, que aborda un problema de gran importancia en los actuales estudios de éticas aplicadas. La ética del humor es una nueva ética aplicada que pretende comprender el fenómeno del humor a la luz de sus implicaciones éticas. Como señala el autor, Juan Carlos Siurana, reputado experto en el ámbito de la filosofía práctica, el interés por el humor es un interés por la ética. En la obra no presenta una nueva teoría filosófica del humor –las cuales se han venido sucediendo, al menos, desde los Diálogos de Platón–, sino una nueva teoría ética, que toma al humor como objeto principal de análisis. Por tanto, la finalidad es realizar una aportación dentro del ámbito de la ética. Para ello se nutre de distintos estudios psicológicos, biológicos, fisiológicos y neurológicos sobre el humor, así como de clásicas obras de filosofía que han abordado esta cuestión.

  1. Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

    Science.gov (United States)

    Gorasia, Dhana G; Veith, Paul D; Hanssen, Eric G; Glew, Michelle D; Sato, Keiko; Yukitake, Hideharu; Nakayama, Koji; Reynolds, Eric C

    2016-08-01

    The type IX secretion system (T9SS) has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component.

  2. Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

    Science.gov (United States)

    Gorasia, Dhana G; Veith, Paul D; Hanssen, Eric G; Glew, Michelle D; Sato, Keiko; Yukitake, Hideharu; Nakayama, Koji; Reynolds, Eric C

    2016-08-01

    The type IX secretion system (T9SS) has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component. PMID:27509186

  3. Cefaleia por uso excessivo de medicamentos

    Directory of Open Access Journals (Sweden)

    Ariane Maria Fonseca MIRANDA

    2015-01-01

    Full Text Available Uma variante da cefaleia crônica diária, a cefaleia por uso excessivo de medicamentos é uma manifestação clínica de frequência ≥ 15 dias por mês, durante 3 meses. Possui um diagnóstico deficiente e um tratamento dividido em etapas, sendo a desintoxicação, a etapa de fundamental importância. Este artigo apresenta uma revisão sobre o tema, contribuindo para o esclarecimento das principais manifestações clínicas, principais teorias envolvendo sua fisiopatologia e a terapêutica farmacológica empregada. A metodologia utilizada foi uma revisão de publicações europeias e americanas, no período de 2001 a 2013, nos idiomas português, inglês e espanhol. Todos os medicamentos utilizados no tratamento sintomático das cefaleias são capazes de cronificar uma cefaleia preexistente, desde que sejam utilizados excessivamente, de forma regular e continuada. A suspensão de tais agentes terapêuticos resultará em melhoria na maioria dos pacientes, porém pode ser necessária a introdução de uma terapia de suporte de transição e/ou terapia profilática. Os tratamentos nao farmacológicos, quando associados ao farmacológico, ampliam a possibilidade de resultados satisfatórios, evitando recaídas.

  4. Bacteremias por bacilos gram-negativos

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    Adrelírio J. R. Gonçalves

    1969-01-01

    Full Text Available São apresentados 31 casos de bacteremia por gram-negativos, assunto que vem merecendo muita atenção dos pesquisadores nos últimos anos. Os organismos etiológicos mais importantes que apareceram em igualdade de freqüência foram Escherichia coli e Klebsiella-Aerobacter, sendo responsáveis por 58% do total das infecções, seguidos por Pseudomonas. A porta de entrada mais freqüente foi o trato urinário em 61,3% dos casos. A infecção foi mais comum no sexo masculino e a faixa etária de 50 a 60 anos predominou. O uso prévio de antibióticos foi um fator predisponente muito importante, seguido pelo uso de esteróides e citostáticos. As principais doenças predisponentes foram diabetes mellitus e neoplasias malignas. Os principais fatores precipitantes foram a manipulação do aparelho urinário, com infecção prévia ou desencadeada, cirurgia do aparelho digestivo, uronatia obstrutiva e obstrução biliar. As principais manifestações clínicas foram a presença de febre, calafrios e hipotensão arterial. A complicação mais freqüente foi o choque bacteriano que incidiu em 58% dos casos, aproximadamente três vêzes aquela relatada na literatura. As outras foram a insuficiência renal aguda, superinfecção e infecção pulmonar metastática. Considerações terapêuticas gerais e esquemas de antibióticos são propostos para estes casos. A mortalidade da bacteremia simples foi de 30,7% e quando associada ao choque elevou-se para 72,2% . As infecções por Pseudomonas foram 100% fatais.

  5. Travesía por mares piratas

    OpenAIRE

    Herrera, Elixabete

    2015-01-01

    Se analiza el viaje del buque quimiquero Mar María por zonas de alto riesgo de piratería, basada en la experiencia de supervivientes a ataques piratas, y se hace un resumen de la regulación legal de la piratería. Se explicitan la valoración de riesgos, las medidas de protección y el plan de contingencia antipirata. La construcción de una ciudadela es otro de los temas que se tratan, así como la manera de identificar a piratas.

  6. Leibniz damnificado por el terremoto de Lisboa

    OpenAIRE

    Evaristo ÁLVAREZ MUÑOZ

    2005-01-01

    RESUMEN: En las páginas que siguen se argumenta que al filósofo alemán Gottfried Wilhelm Leibniz —fallecido en Hannover en 1716— o, al menos, a su obra Teodicea, cabría contarlos, echadas las cuentas de la manera que se verá, entre las víctimas del terremoto de Lisboa de 1755. Asimismo se subraya la persistencia del pensamiento de Leibniz en las respuestas dadas por los filósofos del siglo XVIII al trágico suceso. Se estudian las reacciones de Voltaire, de Rousseau y de Kant ante los estragos...

  7. Estrategias de crecimiento empresarial aplicadas por hipermercados

    OpenAIRE

    Miraidy Leal Morantes; Yilian Cefalá Chirinos

    2003-01-01

    El presente estudio tiene como objetivo caracterizar las estrategias de crecimiento empresarial, representadas por alianzas y adquisiciones, que han sido aplicadas en el sector de distribución de bienes de consumo masivo, específicamente en los hipermercados ubicados en Maracaibo, Estado Zulia, como manera de responder al entorno competitivo y cambiante en el cual se desenvuelven. La investigación se desarrolló a través de un estudio de carácter descriptivo; para la recolección ...

  8. Neumonía por Stenotrophomonas maltophilia

    OpenAIRE

    Verny Huertas-Franco; María Isabel Lacayo-Pallais

    2014-01-01

    La Stenotrophomonas maltophilia es un bacilo gram negativo ambiental emergente que ha venido posicionándose entre el grupo de microorganismos multirresistentes como causa de infección en diversos órganos en ambiente hospitalario y en la comunidad. Se reporta este caso de insuficiencia respiratoria con neumonía severa por S. maltophilia adquirida en la comunidad en una paciente inmunocompetente que tuvo una rápida respuesta a tratamiento con trimetoprim sulfametoxazol cuando se logró identific...

  9. Los Cuentos Por Proyectos De Trabajo Global.

    OpenAIRE

    Reinaldos, María Inmaculada

    2012-01-01

    La educación infantil es importante en los primeros años del niño, ya que un aprendizaje temprano es determinante para un buen desarrollo cognitivo, motor, psicológico, intelectual, emocional, social del individuo, y para la formación de las facultades intelectuales y el desarrollo de la personalidad. La L.O.E. (2006) aboga por una enseñanza globalizada, y que abarque todas las dimensiones del niño, para que de esta forma se consiga un aprendizaje significativo. Actualmente, se apuesta ...

  10. Gestión por competencias

    OpenAIRE

    Patiño Rubiano, Benjamín

    2006-01-01

    El desarrollo de este trabajo tiene como objetivo principal comparar los modelos de gestión por competencias implementados en otras organizaciones para retroalimentarlo en la organización Schneider Electric de Colombia S.A Agencia Antioquia. Para el desarrollo del tema lo primero que se hizo fue hacer un análisis teórico, del cual se presentará una síntesis. Las competencias son la capacidad de hacer algo bien y en determinadas condiciones, su objetivo es el aprovechamiento de las cualidades ...

  11. Regulación por precios tope

    Directory of Open Access Journals (Sweden)

    Gerardo Soto Carrillo

    2009-06-01

    Full Text Available El presente trabajo describe las principales características del mecanismo de regulación por precios tope, incluyendo su ubicación dentro de las posibilidades de acción regulatoria, las críticas que se han planteado al mismo, así como los mecanismos complementarios utilizados y los riesgos involucrados en su desarrollo.---This article describes the main characteristics of the price cap regime of price regulation, including its location among other regulatory possibilities, critics received, complementary mechanisms and risks involved in its development.

  12. Neumonía por Stenotrophomonas maltophilia

    Directory of Open Access Journals (Sweden)

    Verny Huertas-Franco

    2014-03-01

    Full Text Available La Stenotrophomonas maltophilia es un bacilo gram negativo ambiental emergente que ha venido posicionándose entre el grupo de microorganismos multirresistentes como causa de infección en diversos órganos en ambiente hospitalario y en la comunidad. Se reporta este caso de insuficiencia respiratoria con neumonía severa por S. maltophilia adquirida en la comunidad en una paciente inmunocompetente que tuvo una rápida respuesta a tratamiento con trimetoprim sulfametoxazol cuando se logró identificar la bacteria.

  13. Por qué necesitamos la competencia

    OpenAIRE

    Schnappauf, Werner

    2010-01-01

    "La gran aportación de la Economía Social de Mercado es que domestica al capitalismo y lo lleva por caminos ordenados de modo que pone la tendencia humana al beneficio al servicio del bien común, conciliando el beneficio individual y el del conjunto de lasociedad", afirmó Werner Schnappauf, Director General de la Confederación Federal de la Industria Alemana (BDI), con motivo del 43 Simposio de Innsbruck del Instituto de Investigación para la Constitución Económica y la Competencia (FIW), ...

  14. 河北省西部山区蜱传斑点热群立克次体分子流行病学研究%Molecular epidemiological study of tick-borne spotted fever group Rickettsia in western mountain area of Hebei province, China

    Institute of Scientific and Technical Information of China (English)

    冯帅; 吴含; 张力文; 路朝旭; 张成龙; 李志平; 张荣贞; 周慧

    2013-01-01

    Objective To investigate the prevalence of tick-borne spotted fever group Rickettsia (SFGR) in the western mountain area of Hebei province,China and to provide a scientific basis for the prevention and control of tick-borne SFGR.Methods One set of specific primers,designed according to the outer membrane protein A (OmpA) gene sequence of SFGR,were used to amplify the OmpA gene in DNA samples extracted from Haemaphysalis longicornis collected in the western mountain area of Hebei province,and the positive samples were subjected to sequencing and sequence analysis to establish the molecular phylogenetic tree.Results Of 1227 DNA samples,91 (7.42%) were positive for SFGR.The phylogenetic analysis based on nucleotide sequence showed that all detected SFGR strains were clustered together with Candidatus Rickettsia hebeiii (accession numbers:HQ651815,HQ651817,HQ651818,HQ651819,HQ651823,and HQ651824) and Rickettsia sp.Fujian strain FUJ (accession number:AF169629); these strains had the highest homology with Candidatus R.hebeiii (99.02%),followed by Rickettsia sp.Fujian strain FUJ (98.50%),Rickettsia sp.Suifen strain HLJ-054 (accession number:AF179362) and Rickettsia sp.Hulin strain HL-93 (accession number:AF179364) (98.13%),and Rickettsia sp.Japanese strain YM (accession number:U43795) (97.92%).Conclusion Tick-borne SFGR is prevalent in the western mountain area of Hebei province.Preventive measures should be taken in time to protect humans and animals from this disease.%目的 调查河北省西部山区蜱类斑点热群立克次体带菌情况,为蜱传斑点热群防控提供科学依据.方法 根据已发表斑点热群立克次体OmpA外膜蛋白基因序列设计特异性引物,对河北省西部山区采集的长角血蜱进行PCR检测,并对阳性样本进行测序和序列分析,建立分子系统进化树.结果 在1227份蜱DNA样本中检测出91份阳性,阳性率为7.42%;序列分析结果显示河北省西部山区长角血蜱携带立克

  15. Comparação entre diversos antígenos para o diagnóstico de Anaplasma marginale por ELISA Comparison between several antigens for diagnosis of Anaplasma marginale by ELISA

    Directory of Open Access Journals (Sweden)

    Carlos A.N. Ramos

    2010-01-01

    Full Text Available Anaplasmose bovina é uma doença com grande importância nas regiões tropicais e subtropicais do mundo por determinar perdas econômicas devido à mortalidade e redução da produtividade. É causada por Anaplasma marginale, uma riquétsia intraeritrocítica obrigatória cujo controle requer, além de uma vacina eficiente, uma acurada identificação de bovinos cronicamente infectados. Apesar de existirem atualmente diversos métodos de diagnóstico dessa riquétsia, os métodos sorológicos, em particular o ensaio de imunoadsorção enzimática-ELISAs, são os mais utilizados devido à sua versatilidade e praticidade. No entanto, devido ao grande número de antígenos disponíveis, atualmente torna-se necessária uma avaliação para definir quais antígenos apresentam um melhor desempenho no diagnóstico da anaplasmose. Soros de bovinos positivos e negativos para A. marginale por PCR, e soros de animais provenientes do Brasil e Costa Rica, foram testados em ELISAs baseados em MSP1a, MSP2 e MSP5 recombinantes, um pool das três proteínas recombinantes, e antígeno de lisado de corpúsculos iniciais da riquétsia (CI. Utilizando soro de bovinos positivos para A. marginale por PCR, uma maior sensibilidade foi observada no ELISA CI. No entanto, uma maior especificidade, com soro de bovinos negativos a PCR, foi observada com os ELISAs recombinantes. O porcentual de bovinos positivos do Brasil e Costa Rica foi maior com ELISA CI. Razões para essas diferenças são discutidas.Bovine anaplasmosis is a major disease in tropical and subtropical regions of the world by determine economical loss due mortality and productive reduction. The disease is caused by Anaplasma marginale, an intraerythrocytic rickettsia whose control requires, besides an efficient vaccine, the accurate identification of chronically infected cattle. Although the existence of diverse methods of diagnosis of this rickettsia, the serological methods, in particular the enzyme

  16. Sistema de climatización por suelo radiante coalimentado por energías renovables

    OpenAIRE

    Valdivieso Sarabia, Rafael Jesús; García Chamizo, Juan Manuel; Ferrández Pastor, Francisco Javier; Flórez-Revuelta, Francisco

    2010-01-01

    Se presenta el sistema de climatización basado en suelo radiante coalimentado por fuentes de energía renovables, que es capaz de proporcionar calor o frío. Se ha modelado una instalación genérica, que ha sido particularizada e integrada en una vivienda-laboratorio de unos 54m2. El sistema está compuesto por placas termo-solares, calentador eléctrico, bomba de calor aire-agua, acumuladores, circuito de suelo radiante y fancoil. El sistema de control está basado en un autómata que integra senso...

  17. Nodulose por Metotrexato Methotrexate Induced Nodulosis

    Directory of Open Access Journals (Sweden)

    Fernanda Guidolin

    2005-08-01

    Full Text Available A nodulose por metotrexato (MTX é um dos efeitos colaterais pouco conhecidos do uso desse medicamento em doses baixas. Embora classicamente descrita em casos de artrite reumatóide, tem aparecido, também, em outras doenças reumáticas. Descreve-se aqui um caso de nodulose por MTX em uma paciente com artrite reumatóide soropositiva, que utilizava esse medicamento há um ano, com bom controle do processo articular. Segue-se uma breve revisão sobre o assunto.Methotrexate-induced nodulosis is a rare side effect of this drug when it is used in low doses. Although classically described in rheumatoid arthritis patients, it may also appear in other rheumatic disorders. We describe a seropositive rheumatoid arthritis patient who developed methotrexate-induced nodulosis after using this drug for a year, with good control of articular symptoms. This case presentation is followed by a brief revision on the subject.

  18. Choque séptico por ehrliquiosis

    Directory of Open Access Journals (Sweden)

    Viviana Hernández-de Mezerville

    2007-04-01

    Full Text Available La ehrliquiosis humana es una infección zoonótica transmitida por "garrapatas duras" causada por Anaplasma sp y Ehrlichia sp. Puede presentarse como un cuadro pseudogripal con fiebre, malestar general, mialgias y cefalea o hasta un choque séptico con falla multiorgánica y muerte. La mitad de los pacientes requieren atención hospitalaria en algún momento y se reporta una mortalidad de hasta el 5% secundaria a enfermedades oportunistas o a hemorragias. El diagnóstico se puede sospechar visualizando las mórulas intracitoplasmáticas en las células afectadas en frotis de sangre periférica, y se confirma con serología, con cultivos o con detección molecular. El tratamiento de elección es la doxiciclina con buena respuesta clínica. Se reporta un caso probable de ehrliquiosis humana asociado a choque séptico y falla multiorgánica tratado exitosamente en el Hospital Dr. Rafael Angel Calderón Guardia.

  19. Luchas por el control territorial en Colombia

    Directory of Open Access Journals (Sweden)

    Darío I. Restrepo

    2002-01-01

    Full Text Available La tesis central del artículo es que la concurrencia entre los impactos de la globalización, el proceso de descentralización y la crisis política debilitan gravemente el Estado-Nación, y particularmente tienden a romperse las bases mismas del centralismo polÌtico, administrativo y económico. Por otra parte, se exacerban las luchas locales por la apropiación de las riquezas materiales y el control de las instituciones. De esta manera, se acrecienta el poder de negociación política de las fuerzas locales frente al gobierno central, tanto respecto de las funciones descentralizadas como de aquellas que mantiene el Estado de manera centralizada. Neoliberales, reformadores políticos, clases políticas territoriales, nuevos movimientos sociales, narcotraficantes, guerrilleros y paramilitares se disputan abiertamente el poder local. Todos tienen una estrategia, o al menos un conjunto de intereses y prácticas respecto del proceso de descentralización, el cual en última instancia no puede ser entendido sino como el resultado de la complejidad de fuerzas que intervienen en él.

  20. Suicidio por arma de fuego Suicide by firearm

    OpenAIRE

    M. Soriano Maldonado; P. Martínez-García

    2005-01-01

    El mecanismo elegido para cometer el suicidio depende de numerosos factores personales y sociales. En este número presentamos una imagen del tipo de suicidio más mediático, aunque no por ello el más frecuente en nuestro medio. La variabilidad en la forma de los orificios de entrada y salida por arma de fuego depende de la distancia, tipo de arma y región anatómica por lo que puede presentar una morfología muy variada. Es por ello que, aunque ya se han publicado varias imágenes de suicidio por...

  1. Propriedades do Polestireno Modificado por Nanomateriais

    OpenAIRE

    Oliveira, Pedro Xavier Valente de

    2011-01-01

    A incorporação de nanocargas metálicas em matrizes poliméricas, transformando-as em nanocompósitos, constitui um desafio para a investigação em engenharia, no sentido de se dispor de materiais com melhor desempenho físico/mecânico em serviço. No presente estudo foi efectuada a caracterização de nanocompósitos de matriz polimérica reforçada, primeiro por uma carga metálica nanocristalina e posteriormente com adição de nanotubos. A matriz era poliestireno e os reforços nanocristalinos de aç...

  2. Hiperparatiroidismo primario por adenoma paratiroideo mediastinal

    OpenAIRE

    Jeffry Solís-Torres; Esteban Mora-Segura

    2015-01-01

    El hiperparatiroidismo primario cursa con un aumento de la secreción de hormona paratiroidea, generalmente debido a un adenoma, e hipercalcemia. Su presentación clásica se diagnostica con la determinación de calcio sérico y de hormona paratiroidea, asociada con estudios de imágenes. Su tratamiento es quirúrgico y tiene altas tasas de éxito. Se analiza el caso de una paciente hipertensa, de 63 años, con historia de pérdida de apetito y debilidad de un año y medio de evolución, por lo que se le...

  3. La Violencia Latinoamericana vista por los Economistas

    Directory of Open Access Journals (Sweden)

    Salama Pierre

    2003-08-01

    Full Text Available

    Salama, Pierre. "La Violencia Lationoamericana vista por los Economistas", Cuadernos de Economía, V. XXII, n. 38, Bogotá, 2003 páginas 179-198.

    Este articulo sintetiza los estudios económicos publicados recientemente sobre la violencia en América Latina y analiza las causas suceptibles a acrecentarla: pobreza, desigualdad de los ingresos en nivel y variación, impunidad, diferencia entre la probabilidad de ser arrestado y la severidad de la pena impuesta, y narcotrafico. Sin embargo, la explicación de la violencia no se limitará a los factores económicos, puesto que el autor privilegia un enfoque inspirado en la antropología y la sociología.

  4. Síndrome cerebeloso por amiodarona

    Directory of Open Access Journals (Sweden)

    Neuda S. Garretto

    1994-12-01

    Full Text Available La amiodarona (AMD es una droga antiarritmica cuyos efectos adversos pueden comprometer el sistema nervioso central y periferico. La aparición de un síndrome cerebeloso es infrecuente. Se presenta un paciente masculino de 56 anos de edad que desarolla un síndrome pancerebeloso de 4 meses de evolución, que revierte luego de la suspension de la AMD. El cuadro reaparece meses mas tarde luego de un periodo de automedicacion con la droga. Los mecanismos tóxicos por los cuales la AMD afecta al cerebelo permanecen inciertos. Esta droga de amplia difusión en nuestro medio, como otros antiarritmicos, posee efectos sobre el sistema nervioso que deben ser tenidos en cuenta a fin de poder detectarlos precozmente.

  5. Vayamos por partes... dijo Jack el Destripador

    Directory of Open Access Journals (Sweden)

    Miguel Baños González

    2012-04-01

    Full Text Available En la cada día más compleja actividad de comunicación comercial, la publicidad es solamente una herramienta más con diferentes grados de importancia en función del tipo de anunciante. La tendencia a dividir el proceso creativo hasta definir una estructura de fases sucesivas, y en muchos casos de obligado seguimiento, es una visión que se aleja notablemente de la práctica profesional y de la realidad de un mercado holista y global. Por eso, proponemos un cambio de enfoque, analizando la creatividad publicitaria desde una perspectiva que nos permita un conocimiento más profundo, tanto desde punto de vista académico como desde el profesional. 

  6. Toxicidad por óxido de etileno

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    Téllez M. Jairo A.

    1993-08-01

    Full Text Available

    El óxido de etileno, es un compuesto epóxido gaseoso, ampliamente utilizado en nuestro medio como agente esterilizante y de desinfección en instituciones hospitalarias. Los estudios realizados en varios países han demostrado efectos sobre la salud humana, caracterizados por  hipersensibilidad dérmica, irritación del tracto respiratorio, irritación ocular, excitación del S.N.C. y se asocia con presencia de abortos expontáneos, aberraciones cromosómicas e irritación crónica de laringe y tráquea en personal expuesto ocupacionalmente.

  7. fluidizado por proceso autotérmico

    Directory of Open Access Journals (Sweden)

    ZULAMITA ZAPATA BENABITHE

    2005-01-01

    Full Text Available El presente trabajo se basa en el estudio de la producción de carbón activado a partir de carbón mineral subbituminoso en un reactor de lecho fluidizado por proceso autotérmico. El carbón utilizado provino de la región de Amagá (Antioquia - Colombia y fue activado en dos reactores de lecho fluidizado de diferente diámetro interno, 10 cm y 22 cm. Los valores del área superficial específica y el volumen de poro de las muestras activadas fueron determinados a partir de las isotermas de N2 y CO2. Los resultados experimentales mostraron que los valores de áreas superficiales BET y DR y del Índice de Yodo se encontraron alrededor de 460 m2/g (SBET, 490 m2/g (SDR y 460 mg I2/g carbón.

  8. Herida por arma de fuego Gunshot wounds

    OpenAIRE

    A. Sibón Olano; P. Martínez-García; E. Santiago Romero

    2003-01-01

    En el examen de las heridas por arma de fuego, hay que prestar especial interés al orifico de entrada. Un examen minucioso del mismo, nos permitirá conocer la distancia a la que se ha efectuado el disparo; así mismo, nos orientará sobe la trayectoria y etiología médico-legal. El tipo de arma puede modificar en alguna medida el orificio de entrada en los disparos a cañón tocante; como ocurre en las armas de dos cañones, en las que tiene situada su mira en la boca del cañón, o en las que están ...

  9. Choque séptico por ehrliquiosis

    Directory of Open Access Journals (Sweden)

    Viviana Hernández-de Mezerville

    2007-04-01

    Full Text Available La ehrliquiosis humana es una infección zoonótica transmitida por "garrapatas duras" causada por Anaplasma sp y Ehrlichia sp. Puede presentarse como un cuadro pseudogripal con fiebre, malestar general, mialgias y cefalea o hasta un choque séptico con falla multiorgánica y muerte. La mitad de los pacientes requieren atención hospitalaria en algún momento y se reporta una mortalidad de hasta el 5% secundaria a enfermedades oportunistas o a hemorragias. El diagnóstico se puede sospechar visualizando las mórulas intracitoplasmáticas en las células afectadas en frotis de sangre periférica, y se confirma con serología, con cultivos o con detección molecular. El tratamiento de elección es la doxiciclina con buena respuesta clínica. Se reporta un caso probable de ehrliquiosis humana asociado a choque séptico y falla multiorgánica tratado exitosamente en el Hospital Dr. Rafael Angel Calderón Guardia.Human ehrlichiosis is a tick-borne infectious disease caused by Anaplasma sp and Ehrlichia sp. The presentation can range from a flu-like syndrome with fever, malaise, myalgia and headache to a septic shock state with multiorganic dysfunction. Half the patients require in- hospital care and the mortality rate is 5% as a result of opportunistic infections or hemorrhage. The diagnosis can be made by the visualization of intracytoplasmatic morulae in the blood smear, serology, cultives or polymerase chain reaction. The treatment of choice is doxycicline and generally carries a good response. We report a case of human ehrlichiosis associated with septic shock and multiorganic dysfunction successfully treated at the Calderon Guardia Hospital.

  10. Hiperparatiroidismo primario por adenoma paratiroideo mediastinal

    Directory of Open Access Journals (Sweden)

    Jeffry Solís-Torres

    2015-06-01

    Full Text Available El hiperparatiroidismo primario cursa con un aumento de la secreción de hormona paratiroidea, generalmente debido a un adenoma, e hipercalcemia. Su presentación clásica se diagnostica con la determinación de calcio sérico y de hormona paratiroidea, asociada con estudios de imágenes. Su tratamiento es quirúrgico y tiene altas tasas de éxito. Se analiza el caso de una paciente hipertensa, de 63 años, con historia de pérdida de apetito y debilidad de un año y medio de evolución, por lo que se le realizaron exámenes de laboratorio que revelaron hipercalcemia y elevación de la hormona paratiroidea. Se le indicó entonces una gamagrafía con Tecnecio 99, que evidenció un nódulo de 18mm de diámetro, ubicado 2 centímetros caudal al lóbulo tiroideo derecho. Se le efectuó una exploración cervical sin encontrarse la lesión, por lo que requirió una esternotomía media superior, que permitió encontrar un adenoma en el mediastino superior, detrás de la vena braquiocefálica derecha, de manera que se procedió a su extracción. Los controles de calcio y de hormona paratiroidea a las 24 horas estaban entre los límites normales, y se egresó.

  11. 罗非鱼类立克次氏体病的组织病理学观察%Histopathological Observation of Disease of Rickettsia-like Organism in Tilapia (Oreochromis niloticus)

    Institute of Scientific and Technical Information of China (English)

    戚瑞荣; 唐绍林; 崔龙波; 雷燕; 马家好

    2016-01-01

    本文主要研究感染类立克次氏体(Rickettsia-like organism,RLO)的养殖罗非鱼(Oreochromis aureus ♂×Oreochromis niloticus♀)肝、脾、肾、肠、鳃和心脏的组织病理变化.感染类立克次氏体的罗非鱼各器官广布粗糙不圆整的白色小结节,这些结节为肉芽肿坏死灶,分层不典型,与周围健康组织的界限不甚明显;严重病变的组织坏死区域较大,与周围明显增生的细胞形成清晰的巨大“肉瘤”状肿物.经吉姆萨-瑞氏染色后,在病变组织内,尤其是脾肾组织的巨噬细胞胞质内可见蓝紫色球状或颗粒样、成簇分布的类立克次氏体.这些发现可为罗非鱼类立克次氏体病的病理学诊断提供依据.

  12. Encefalitis aguda: Manifestaciones neuropsiquiátricas como expresión de infección por virus de influenza Acute encephalitis: Neuropsychiatric manifestations as expression of influenza virus infection

    Directory of Open Access Journals (Sweden)

    Noris Moreno-Flagge

    2009-01-01

    Full Text Available El objetivo fue revisar la encefalitis en niños y adolescentes, su etiología, manifestaciones clínicas, fisiopatología, métodos diagnósticos y tratamiento, enfatizando las manifestaciones neuropsiquiátricas de la encefalitis durante una epidemia de influenza. La encefalitis se considera una inflamación del sistema nervioso central (SNC que compromete el cerebro. Se manifiesta usualmente por cefaleas, fiebre y trastorno del estado de conciencia. Puede además manifestarse por convulsiones, cambios en la personalidad y manifestaciones obsesivas (síntomas neuropsiquiátricos. Las manifestaciones dependerán del tipo de virus y las células afectadas. La encefalitis puede ser causada por una gran variedad de agentes infecciosos incluyendo virus, bacterias, hongos y parásitos. Causas virales de encefalitis incluyen herpesvirus, arbovirus, rabia y enterovirus. Casos establecidos de bacterias incluyen Borrelia burgdorferi y rickettsia y el Mycoplasma neumoniae, al cual se atribuyen varios casos de encefalitis. Otros agentes como el hongo Coccidioides immitis e Histoplasma capsulatum pueden también generarla. Más de 100 agentes se han asociado a encefalitis. El diagnóstico de encefalitis constituye un reto para el clínico, y su etiología infecciosa usualmente se identifica entre el 40% al 70% de casos. El diagnóstico se hace con absoluta certeza sólo con una biopsia cerebral. La epidemiología depende de ciertos factores como la edad, la localización geográfica, la época del año, las condiciones climáticas y la inmunocompetencia del huésped. El tratamiento temprano puede disminuir el riesgo de muerte y las secuelas. Describimos cuatro pacientes con encefalitis y manifestaciones neuropsiquiátricas durante una epidemia de influenza, con el fin de alertar sobre esta asociación.The aim is to review the encephalitis in infants and adolescents as well as its etiology, clinical manifestation, epidemiology, physiopathology, diagnostic

  13. ¿Inconstitucionalidad por omisión?

    Directory of Open Access Journals (Sweden)

    Alfredo Quispe Correa

    2006-01-01

    Full Text Available El autor realiza un análisis del sistema peruano de control de constitucionalidad desarrollado en control abstracto por el Tribunal Constitucional y en control concreto por los tribunales de justicia, para luego centrar su análisis sobre la inconstitucionalidad por omisión, considerando la doctrina desarrollada en la materia, planteando sus reservas en la materia, especialmente cuando el tribunal constitucional se convierte en legislador positivo.

  14. Estudio electrofisiologico en la neuropatia por Vincristina

    Directory of Open Access Journals (Sweden)

    Olga P. Sanz

    1975-12-01

    Full Text Available Diez pacientes afectados por diversas patologías que requerían tratamiento crónico con Vincristina, fueron sometidos a estudios electrofisiológicos en los que se valoró: el número de unidades motoras (UM funcionantes en los músculos de la eminencia tenar, los valores de los incrementos medios de UM, velocidad de conducción motora y su latencia residual en el nervio mediano, la velocidad de conducción sensitiva del mismo nervio y el estado de la transmisión neuromuscular. Los valores obtenidos fueron comparados con grupos controles. Los resultados mostraron disminución del número de UM; las UM remanentes presentaron amplitud reducida junto a otras cuyo tamaño no superaba el del grupo control, hecho que sugiere la incapacidad de lograr una reinervación adecuada. Las velocidades de conducción motora y sensitiva mostraron valores diminuídos, con mayor compromiso en los segmentos distales. Junto a estos datos se halló respuesta miasteniforme al estímulo repetitivo. Todos estos resultados permiten postular la existencia de un compromiso de la unidad motora, abarcando todos sus segmentos, en pacientes intoxicados con Vincristina.

  15. Por uma nova ética ambiental

    Directory of Open Access Journals (Sweden)

    Edna Parizzi de Viveiros

    2015-09-01

    Full Text Available RESUMOEste artigo procura abordar a relação do homem com o ambiente. Entre outros pontos de discussão, argumenta que o cientificismo contribuiu para que se aprofundasse a visão de posse absoluta e exploração implacável sobre a natureza (terra, água, florestas, e que as fragilidades apresentadas pelo Planeta na atualidade são resultados do modo pelo qual se deu essa relação, ou seja, o modo como a partir do "domínio" sobre a natureza, o homem dilapidou e continua dilapidando os recursos naturais, com o intuito de produzir cada vez mais bens para o consumo, gerar e concentrar riquezas. Por fim, o artigo trata da emergência da educação ambiental e da prática interdisciplinar entre saberes, para que se possa construir uma nova ética ambiental, tão necessária à sobrevivência do Planeta.

  16. Libertad, igualdad, sostenibilidad. Por un ecofeminismo ilustrado

    Directory of Open Access Journals (Sweden)

    Puleo, Alicia H.

    2008-06-01

    Full Text Available This article presents the proposal of an enlightened Ecofeminism and defines it as an ethic-political thinking about human relations to Nature. It aims at ecojustice and sustainability, which are characterized through the criticism of prejudice, through the principles of equality and autonomy, and through the nominalist conceptualization of gender, intercultural dialogue and the sensible acceptance of science and technique. The enlightened Ecofeminism universalizes virtues such as caring for the human and non-human Nature, and defends a compassionate moral towards the radical finitude of the world.

    En este artículo se presenta la propuesta de un ecofeminismo ilustrado entendido como reflexión ético-política sobre las relaciones de los humanos con la Naturaleza. Orientado a la ecojusticia y la sostenibilidad, el ecofeminismo ilustrado se caracterizaría por la crítica al prejuicio, la defensa de los principios de igualdad y autonomía, la conceptualización nominalista del género, el diálogo intercultural, la aceptación prudente de la ciencia y la técnica, la universalización de las virtudes del cuidado aplicadas a los humanos y al resto de la Naturaleza, y una moral de la compasión frente a la radical finitud del mundo.

  17. Identidad e interculturalidad: un horizonte por visitar

    Directory of Open Access Journals (Sweden)

    Marian Pérez Bernal

    2016-01-01

    Full Text Available En el presente trabajo mantenemos que el concepto de identidad defendido por Amin Maalouf puede ser una interesante vía para conseguir una aproximación entre las distintas culturas capaz de conducirnos a un diálogo fructífero que nos permitan gestionar la multiculturalidad actual. Defendemos que las culturas sean vistas como escenas de debate y contestación en constante proceso de construcción y reconstrucción y en las que siempre primen unos valores que nos conciernen a todos y que han de ser irrenunciables.In this paper, it is stated that the concept of identity defended by Amin Maalouf could be an interesting way to achieve a rapprochement amongst different cultures. This could lead to a fruitful dialog allowing to manage today’s multiculturalism. It is also defended that cultures should be considered as instruments of debate and reply on a continuous process of construction and reconstruction. However, cultures should not prevail over a series of values that concern to all of us and that should be inalienable.

  18. Herida por arma de fuego Gunshot wounds

    Directory of Open Access Journals (Sweden)

    A. Sibón Olano

    2003-01-01

    Full Text Available En el examen de las heridas por arma de fuego, hay que prestar especial interés al orifico de entrada. Un examen minucioso del mismo, nos permitirá conocer la distancia a la que se ha efectuado el disparo; así mismo, nos orientará sobe la trayectoria y etiología médico-legal. El tipo de arma puede modificar en alguna medida el orificio de entrada en los disparos a cañón tocante; como ocurre en las armas de dos cañones, en las que tiene situada su mira en la boca del cañón, o en las que están dotadas de bocacha apagafuegos.When examining firearm wounds, special attention must be paid to the entrance wound. Meticulous examination will establish the range at wich the shot was fired as well as the trajectory and the manner of death (forensic etiology. In a contact gunshot wound, the type of weapon can modify the entrance wound to some extent. This is what happens in double barrel muzzle or in those endowed with a fireguard.

  19. Estrategias de crecimiento empresarial aplicadas por hipermercados

    Directory of Open Access Journals (Sweden)

    Miraidy Leal Morantes

    2003-01-01

    Full Text Available El presente estudio tiene como objetivo caracterizar las estrategias de crecimiento empresarial, representadas por alianzas y adquisiciones, que han sido aplicadas en el sector de distribución de bienes de consumo masivo, específicamente en los hipermercados ubicados en Maracaibo, Estado Zulia, como manera de responder al entorno competitivo y cambiante en el cual se desenvuelven. La investigación se desarrolló a través de un estudio de carácter descriptivo; para la recolección de datos se aplicó un cuestionario estructurado, bajo la modalidad de entrevista, a gerentes generales y financieros. Los resultados evidencian que las estrategias de crecimiento empresarial utilizadas son la apertura de nuevos establecimientos comerciales, adquisición de empresas y participación accionaria en grandes cadenas, las cuales propician la concentración del mercado de distribución comercial, afectando a algunas empresas venezolanas del sector cuya oferta no puede competir; asimismo, los proveedores se enfrentan a cadenas con gran poder de negociación.

  20. La responsabilidad del Estado por el hecho del legislador

    OpenAIRE

    María Consuelo Alonso; Eric Leiva Ramírez

    2011-01-01

    Analizar el fenómeno de la responsabilidad del Estado causada por los hechos del legislador ha sido un trabajo desarrollado tanto por la doctrina como por la jurisprudencia internacional a mediados del siglo xx. En Francia, por ejemplo, se presentó el primer antecedentejurisprudencial en el año de 1934. En España, su estudio empezó a gestionarse con la promulgación de la Constitución de 1978, dándose el primer fallo judicial en el año de 1993. Para el caso colombiano, la Constitución de 1991 ...

  1. Epidemiología de la incapacidad temporal por contingencia común por neoplasias en España

    OpenAIRE

    Díez García, Raquel

    2014-01-01

    [ES]Objetivos: Conocer la incidencia de neoplasias en una población trabajadora perteneciente a empresas cuyos episodios de Incapacidad Temporal (IT) por Contingencia Común estaban gestionados por una Mutua de Accidentes de Trabajo y Enfermedades Profesionales de ámbito estatal. Material y Método: Estudio descriptivo, observacional y retrospectivo. Se contabilizaron los casos de neoplasias registrados en la población trabajadora protegida por la Mutua durante el periodo comprendido entre e...

  2. Motivado por cirujanos Motivated by Surgeons

    Directory of Open Access Journals (Sweden)

    Carlos Salazar-Vargas

    2010-12-01

    Full Text Available Comenzaba la década de los 60 y nuestro grupo nerviosamente iniciaba lecciones en los hospitales de San José. En aquellos años, el estudiante de medicina empezaba su contacto con pacientes, por lo menos 1 ó 2 años después de iniciada la carrera. El estudio del ser humano normal que ya habíamos concluido, continuaba con el del enfermo, y más adelante aprenderíamos el tratamiento. La enfermedad descrita en el libro, de pronto se convertía en un enfermo, y es a este quien hoy veíamos, cohibido pero inquisidor, en la cama de un hospital. Los profesores nos enseñaban a interrogar y a examinar a los pacientes, y cada gesto suyo, cada pregunta, cada maniobra, eran celosamente guardados en la memoria de los educandos. Con claridad percibíamos, aun a temprana edad, las diferencias entre los especialistas, y casi de manera involuntaria, cada quien iba tomando partido y escogía su futuro camino. Fue durante esos tempranos años, cuando mi vida se cruzó con la de 7 maravillosas personas y excelentes cirujanos, que marcaron para siempre mi destino y, sin quererlo ellos, me hicieron inclinarme por la cirugía. Dos eran serios y profundamente académicos: el Dr. Manuel Aguilar Bonilla y el Dr. Vesalio Guzmán Calleja; 3, decididos, incansables y muy hábiles: el Dr. Longino Soto Pacheco, el Dr. Claudio Orlich Carranza y el Dr. Carlos Prada Díaz, y 2, abordables, prácticos, joviales y amistosos: el Dr. Fernando Valverde Soley y el Dr. Randall Ferris Iglesias….During the early 60´s our class just started clinical lessons in different hospitals of San Jose. In those years the medical student became in contact with patients 1 or 2 years after initiating his or her career. The study of the normal human being continued with that of the diseased and later on we would learn how to treat our patients. The disease described in our textbooks, suddenly was a reality, a person lying in a hospital bed, shy but inquisitive. Our teachers taught us how to

  3. Study of the five Rickettsia prowazekii proteins annotated as ATP/ADP translocases (Tlc): Only Tlc1 transports ATP/ADP, while Tlc4 and Tlc5 transport other ribonucleotides.

    Science.gov (United States)

    Audia, Jonathon P; Winkler, Herbert H

    2006-09-01

    The obligate intracytoplasmic pathogen Rickettsia prowazekii relies on the transport of many essential compounds from the cytoplasm of the eukaryotic host cell in lieu of de novo synthesis, an evolutionary outcome undoubtedly linked to obligatory growth in this metabolite-replete niche. The paradigm for the study of rickettsial transport systems is the ATP/ADP translocase Tlc1, which exchanges bacterial ADP for host cell ATP as a source of energy, rather than as a source of adenylate. Interestingly, the R. prowazekii genome encodes four open reading frames that are highly homologous to the well-characterized ATP/ADP translocase Tlc1. Therefore, by annotation, the R. prowazekii genome encodes a total of five ATP/ADP translocases: Tlc1, Tlc2, Tlc3, Tlc4, and Tlc5. We have confirmed by quantitative reverse transcriptase PCR that mRNAs corresponding to all five tlc homologues are expressed in R. prowazekii growing in L-929 cells and have shown their heterologous protein expression in Escherichia coli, suggesting that none of the tlc genes are pseudogenes in the process of evolutionary meltdown. However, we demonstrate by heterologous expression in E. coli that only Tlc1 functions as an ATP/ADP transporter. A survey of nucleotides and nucleosides has determined that Tlc4 transports CTP, UTP, and GDP. Intriguingly, although GTP was not transported by Tlc4, it was an inhibitor of CTP and UTP uptake and demonstrated a K(i) similar to that of GDP. In addition, we demonstrate that Tlc5 transports GTP and GDP. We postulate that Tlc4 and Tlc5 serve the primary function of maintaining intracellular pools of nucleotides for rickettsial nucleic acid biosynthesis and do not provide the cell with nucleoside triphosphates as an energy source, as is the case for Tlc1. Although heterologous expression of Tlc2 and Tlc3 was observed in E. coli, we were unable to identify substrates for these proteins. PMID:16923893

  4. STUDIES ON RICKETTSIA-LIKE ORGANISMS INFECTING ERIOCHEIR SINENSIS%中华绒螯蟹感染类立克次氏体微生物的研究

    Institute of Scientific and Technical Information of China (English)

    王进科; 朱清顺; 周刚; 张凤英

    2003-01-01

    对"颤抖病"中华绒螯蟹病蟹病理组织超显微结构观察表明,在病蟹鳃上皮细胞、肝胰腺细胞及血淋巴细胞中存在大量类立克次氏体(rickettsia-like organism,RLO)微生物.RLO主要以包含体形式存在于寄主细胞的细胞质中,同时也能散在或群居状存在于包含体外的细胞质内.RLO细胞形态主要有两类,即初级体细胞型和中间体细胞型.初级体RLO表现为体积较小、电子密度深染的球状颗粒.中间体RLO呈现球状、椭圆体及棒状等多种细胞形态.中间体RLO能以二分裂和出芽两种方式繁殖.人工感染实验表明,RLO能通过水体经鳃感染健康蟹,使其表现颤抖病症状.血淋巴细胞中RLO的存在及电镜对不同发病时期病蟹组织的观察结果说明,RLO能够依靠血淋巴循环迅速从最初感染的鳃组织向肝胰腺扩散,形成系统感染,导致器官组织细胞机能紊乱. 图版2 参24

  5. OPINIÓN: PARA TRABAJAR POR CARTAGENA POR DÓNDE COMENZAR?

    Directory of Open Access Journals (Sweden)

    Carmen Cabrales Vargas

    2004-08-01

    Full Text Available Ciertamente son muchos los flancos desde los cuales acercarnos a esta ciudad que se encuentra en permanente y profunda movilidad con respecto a lo que era hace dos décadas. Cartagena ha estallado y seguirá estallando en muchos pedazos, convirtiéndose en una ciudad que por su compleja dinámica no alcanza a recomponerse en su organización social ni en sus espacios físicos; por ello se nos muestra como un lugar donde la confrontación con el orden instituido para su funcionamiento es permanente. En ese sentido, puede anotarse que son pocos los que acogen con rigor las normas de tránsito o respetan el espacio público, o practican el cuidado ambiental o respetan el derecho del otro al uso de los recursos institucionales que se ofrecen. Dicho de otra forma, en los imaginarios de estos habitantes parece no encontrarse el de la ciudad en cuanto organización espacial con reglas y normas que le dan sentido.

  6. Mujeres por la utilidad de la virtud

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    Nancy Rodríguez Pupo

    2014-08-01

    Full Text Available La mujer cubana ostenta una vasta tradición combativa y es ejemplo de entereza, abnegación, sacrificio y compromiso social. Quien se acerque a la historia de nuestro proceso nacional-liberador a todo lo largo de su devenir, constatará su presencia como forjadoras de la nación. Integrante fundamental de la sociedad, la mujer hizo suyas las ansias libertadoras y desempeñó un rol importante en aras de crear una patria común. Se trata de entender que en lo más mínimo su papel fue de “retaguardia”, sino todo lo contrario, su trabajo fue necesario y en no pocas ocasiones empuñó las armas y con valentía gritó ¡viva Cuba libre!, incluso a cambio de su vida, como lo protagonizó la tunera Mercedes Varona. El ejemplo de la mujer cubana y particularmente tunera, es imperecedero en su doble función de ser social y generadora de nuevas vidas, con amplias posibilidades de realización personal y profesional luego de 1959. Su actuación se manifiesta en cada actividad del sector de la salud pública como médica, enfermera, técnica, profesora y estomatóloga, así como también en otros puestos de trabajo no menos necesarios. Ellas con altruismo, solidaridad, responsabilidad y humanismo, son continuadoras de las mejores tradiciones científicas, patrióticas y revolucionarias de nuestro pueblo. Esta edición se dedica al 8 de marzo, día internacional de la mujer, las homenajeamos y recordamos la obra de Laura Martínez Carvajal, primera médica cubana, quien desafió los prejuicios de su época o Isabel Rubio que puso sus conocimientos de medicina farmacéutica al servicio del Ejército Libertador, en el que alcanzó los grados de capitana de sanidad; por citar dos entre las grandes. Otras féminas de la localidad ejercieron en la manigua sus dotes de parteras o enfermeras, tal el caso de Anita Cruz, magnífica artillera, quien estuvo al frente de un hospital de campaña durante la guerra. Allí curó heridas, infecciones, disenter

  7. Epidemia de hepatite veiculada por gamaglobulina contaminada

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    Anastácio Ferreira Morgado

    1982-12-01

    gamaglobulina foram testadas, em laboratórios de referência da Organização Mundial de Saúde, encontrando-se o Ag HB em seis (54,5%J. Os autores concluem que houve alguma falha grave no processo de preparo da gamaglobulina em apreço. E por isto deve-se ter reservas quanto á noção difundida de que esse medicamento está isento do risco de transmitir o vírus hepatite.

  8. Mortalidad por tumores en Santander, 1998-2006

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    Laura Andrea Rodríguez Villamizar

    2008-07-01

    Full Text Available Objetivo: Describir la mortalidad por tumores en el departamento de Santander, Colombia, en el período comprendido entre 1998 y 2006. Métodos: Estudio descriptivo, longitudinal de recolección retrospectiva basado en registros oficiales nacionales. Se realizó análisis de mortalidad por sexo, edad, zona de residencia y tipo de tumor. Resultados:Se registró un total de 13,219 defunciones, con una tasa promedio anual de 76.2 casos por 100,000 habitantes; lastasas más altas se presentaron a partir del año 2002. Elriesgo de morir fue 5% superior en los hombres, exceptoentre los de 25 y 54 años, donde fue superior en las mujeres.El tumor maligno de estómago fue el más frecuente como causa de muerte (tasa mediana 11.8 por 100,000 habitantes. En las mujeres este tumor fue seguido por los tumores malignos de mama y cuello de útero, con tasas medianas de 8.1 y 7.7 por 100,000 habitantes, mientras que en los hombres por los tumores malignos de próstata y debronquios y pulmón, con tasas medianas de 10.7 y 8.3 casos por 100,000 habitantes. Conclusiones: La mortalidad por tumores en Santander constituye la segunda causa de muerte y lleva a fortalecer el diagnóstico temprano de esta enfermedad y de las estrategias poblacionales dirigidas al control de los factores de riesgo.

  9. Impacto do manejo da água na toxidez por ferro no arroz irrigado por alagamento

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    Fabiana Schmidt

    2013-10-01

    Full Text Available A toxidez por ferro é o distúrbio nutricional de maior ocorrência em arroz (Oryza sativa L. cultivado em sistemas alagados, derivada da quantidade excessiva de íons ferrosos (Fe2+ gerados pela redução de óxidos de ferro em solos alagados. Em experimento conduzido em casa de vegetação, foram avaliados os efeitos de manejos da água de irrigação na dinâmica de redução de um Planossolo e na manifestação da toxidez por ferro em arroz. Os tratamentos dispostos em blocos completos ao acaso com quatro repetições constaram de cinco manejos da água: T1- início do alagamento no estádio V2-V3 do arroz; T2- início do alagamento no estádio V6-V7; T3- T1 e drenagem no estádio V10-V11; T4- T2 e drenagem no estádio V10-V11; e T5- T1 e drenagens nos estádios V7-V8 e V10-V11. O atraso do início do alagamento para o estádio V6-V7 do arroz manteve os valores do Eh da solução do solo mais elevados, promovendo menor disponibilidade de Fe2+ na solução do solo e deslocando a máxima liberação de Fe2+ na solução do solo para estádios fenológicos mais avançados do arroz. A realização de drenagens ao longo do ciclo vegetativo do arroz promoveu a reoxidação do solo, que ocasionou o aumento dos valores de Eh e redução da concentração de Fe2+ na solução do solo. O uso de drenagens durante o período vegetativo do arroz foi eficiente no controle da toxidez por excesso de ferro, em arroz cultivado em solo alagado.

  10. El tiempo libre y ocio reivindicado por los trabajadores

    OpenAIRE

    Guillermo Miranda Román

    2006-01-01

    Estas líneas están referidas a la realización de actividades del ocio en el tiempo libre que como derecho ha sido logrado por las luchas de aquellas sociedades cuyo desarrollo industrial y comercial es caracterizado por la designación de tiempos para la producción o distribución de las mercancías. Los trabajadores históricamente han luchado por el derecho a un tiempo libre necesario para el desarrollo de las aptitudes del hombre, asunto que tratamos de discurrir, o en el mejor de ...

  11. Topoplastia de Cvintal assistida por laser de femtossegundo

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    Alexandre Takayoshi Ishizaki

    2013-06-01

    Full Text Available Apresentamos um relato de astigmatismo tardio progressivo pós-transplante de córnea para ceratocone, associado à afinamento periférico na junção doador-receptor, o que presumidamente pode ser considerado como recorrência da ectasia. O caso foi tratado por meio de Topoplastia de Cvintal assistida por laser de femtossegundo para a confecção da incisão com geometria "top hat", seguido de sutura com ajuste per-operatório guiado por ceratoscopia.

  12. La responsabilidad del Estado por la actividad del legislador

    OpenAIRE

    María Consuelo Alonso García; Eric Leiva Ramírez

    2012-01-01

    Analizar el fenómeno de la responsabilidad del Estado causada por los hechos del legislador ha sido un trabajo desarrollado tanto por la doctrina y la jurisprudencia internacional a mediados del siglo xx. En Francia, por ejemplo, se presentó el primer antecedente jurisprudencial en el año de 1934. En España, su estudio empezó a gestionarse con la promulgación de la Constitución de 1978, presentándose el primer fallo judicial en el año de 1993. Para el caso colombiano, la Constitución de 1991 ...

  13. Perforación intestinal por un palillo de dientes

    OpenAIRE

    Marvin Yglesias-Rosales; Andrea Medina-Méndez; Andrea Rodríguez-González

    2006-01-01

    Existe una gran variedad de cuerpos extraños que son deglutidos por los seres humanos, entre los cuales son numerosos los que pueden producir una perforación del tracto gastrointestinal. Se enfocará esta discusión en los palillos de dientes, caso particular, por poseer 2 extremos puntiagudos, lo que hace se consideren como portadores de una gran morbimortalidad. El espectro de manifestaciones clínicas asociado con las lesiones por palillos de dientes ingeridos es muy amplio; el diagnóstico de...

  14. El aprendizaje por indagación I.

    OpenAIRE

    Gómez Martín, Francisco

    2013-01-01

    Este artículo explora cómo se puede usar el aprendizaje por indagación en la enseñanza de las matemáticas. En las matemáticas hace años que se emplea bajo múltiples formas: aprendizaje por resolución de problemas, el método Moore, aprendizaje por proyectos, aprendizaje orientado al proceso, entre otros. En la música, a la luz de nuestro más leal conocimiento, parece que apenas está implantado.

  15. Selección de Recursos Humanos por Competencias

    OpenAIRE

    Sánchez Domingo, Cristina

    2013-01-01

    Los objetivos de este trabajo son, por un lado conocer en qué consisten los procesos de valoración y selección de personas desde el enfoque de las competencias laborales. Para ello, ha sido preciso profundizar en el estudio del concepto de “competencia laboral”, y comprender qué es la Gestión de Recursos Humanos por Competencias, en cuyo seno se encuentra la propia Selección de Recursos Humanos. Por otra parte, un segundo objetivo del trabajo es conocer el grado de implantación de la Selecció...

  16. Aprendizaje por refuerzo en espacios de estados continuos

    OpenAIRE

    Fernández Rebollo, Fernando

    2002-01-01

    El aprendizaje por refuerzo es un modelo de aprendizaje que permite implementar comportamientos inteligentes de forma automática. La mayor parte de la teoría del aprendizaje por refuerzo tiene su fundamento en la programación dinámica, y por tanto, en lo que se denominan funciones de valor. Sin embargo, la implementación tradicional de estas funciones en forma tabular no es práctica cuando el espacio de estados es muy grande, o incluso infinito. Cuando se produce esta situación, se deben apli...

  17. El tiempo libre y ocio reivindicado por los trabajadores

    Directory of Open Access Journals (Sweden)

    Guillermo Miranda Román

    2006-01-01

    Full Text Available Estas líneas están referidas a la realización de actividades del ocio en el tiempo libre que como derecho ha sido logrado por las luchas de aquellas sociedades cuyo desarrollo industrial y comercial es caracterizado por la designación de tiempos para la producción o distribución de las mercancías. Los trabajadores históricamente han luchado por el derecho a un tiempo libre necesario para el desarrollo de las aptitudes del hombre, asunto que tratamos de discurrir, o en el mejor de los casos, reflexionar.

  18. Detection of co-infection with Lyme spirochetes and Spotted fever group rickettsiae in a group of Haemaphysalis longicornis%一组长角血蜱中检出莱姆病螺旋体和斑点热群立克次体复合感染

    Institute of Scientific and Technical Information of China (English)

    孟真; 姜理平; 陆群英; 程苏云; 叶菊莲; 占利

    2008-01-01

    目的 了解浙江省山区野生动物和蜱中莱姆病、斑点热、埃立克体病(无形体病)的感染情况.方法 采用巢式PCR对采集的鼠、蜱标本进行莱姆病伯氏疏螺旋体、斑点热群立克次体、埃立克体(无形体)特异性核酸片段检测分析.结果 从121份鼠标本和105组蜱标本中检出阳性结果 14份.鼠标本中检出伯氏疏螺旋体5S~23S rDNA间隔区片段1份和埃立克体(无形体)16SrDNA 5'端片段2份.蜱标本中检出阳性11份,包括伯氏疏螺旋体5S~23S rDNA间隔区片段3份和斑点热群立克次体外膜蛋白OmpA基因5'端片段8份.其中1组长角血蜱成虫标本为伯氏疏螺旋体和斑点热群立克次体复合感染,5S~23S rRNA基因间隔区和ompA基因片段均阳性,分别与伯氏疏螺旋体法雷氏基因型和马赛立克次体株等关系较近.结论 在同一组长角血蜱成虫中同时检出莱姆病疏螺旋体和斑点热群立克次体复合感染.%Objective The present study was conducted to investigate the infection of Lyme disease, Spotted fever, Ehrlichiosis (anaplasmosisin) in wild animals and ticks in the mountain areas of Zhejiang province. Methods Nested polymerase chain reaction was used to amplify specific DNA sequences of Lyme spirochetes, Spotted fever group rickettsiae, Ehrlichia (anaplasma) from samples of mice and ticks. Results 14 positive samples were identified from 121 mice and 105 groups of ticks. Among mice samples, one positive 5S-23S rDNA intergenic spacer of Borreia burgdorferi and two 5' fragments of Ehrlichia (anaplasma) 16S rDNA were obtained. 11 positive results were detected from tick samples including three 5S-23S rDNA intergenic spacer regions of Borreia burgdorferi and eight 5' fragments of Spotted fever group rickettsiae outer member protein A gene. One group of adult ticks, Haemaphysalis longicornis, which had been collected from eastern mountain area were detected to have co-infected with Lyme spirochetes and

  19. Ansiedad percibida por los pacientes hospitalizados por quemaduras, en una Unidad de Quemados

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    M. Alcázar-Gabás

    2014-06-01

    Full Text Available El presente trabajo, pretende describir el estado de ansiedad que experimentan los pacientes ingresados en una Unidad de Quemados. Uno de los factores clave en los cuidados del paciente quemado es una buena atención psicológica. La realidad demuestra que es el profesional de enfermería quien observa los síntomas emocionales durante los primeros días de ingreso y trata de responder a esa demanda de cuidado. Pretendemos, a través de la medición del nivel de ansiedad que perciben los pacientes ingresados en la Unidad de Quemados elegida para nuestro estudio durante el primer semestre del año 2009, identificar a aquellos que estén en riesgo de padecer mayores niveles de ansiedad durante su hospitalización, para así poder establecer un plan de cuidados adaptado a las necesidades emocionales de cada uno. Los resultados obtenidos nos permiten concluir que los pacientes quemados ingresados en la Unidad de Quemados presentaron niveles elevados de ansiedad que son superiores entre la población femenina, así como en aquellos pacientes con lesiones de mayor extensión. Determinamos también que los pacientes ingresados por quemaduras en la Unidad de Quemados a estudio fueron mayoritariamente varones, de nacionalidad española, residentes en medio urbano con una media de edad de 50 años, siendo las quemaduras producidas por llama en accidentes domésticos la causa más frecuente.

  20. LOGROS DEL FITOMEJORAMIENTO PARTICIPATIVO EVALUADO POR LOS PRODUCTORES INVOLUCRADOS

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    R. Ortiz

    2009-01-01

    un importante empoderamiento del campesino y un aumento significativo de la autoestima del campesino y su familia. Por último, se denotó un efecto de esta estrategia de mejoramiento en la innovación local.

  1. Limitado por lo políticamente correcto.

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    Juan Carlos Ceballos Salgado

    2005-01-01

    Full Text Available He comenzado a sentirme limitado por tanta correctividad política que se nos ha impuesto tanto por el ala derecha como la izquierda. Ambas partes constantemente intentan infringir nuestra libertad diciéndonos que podemos o no podemos, decir o hacer. Me estoy hartando de esto. A continuación algunos ejemplos acerca de lo que están tratando de imponernos.

  2. Secagem por spray: uma revisão

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    Arlan Caldas Pereira Silveira

    2013-04-01

    Full Text Available O objetivo deste artigo foi apresentar os princípios da secagem por spray e os mais recentes resultados de pesquisas na área de leite e derivados. Visando abranger este assunto, o artigo foi dividido em seis partes: introdução, princípios da secagem por spray, atomização, secagem em estágios, resultados de pesquisas e conclusão.

  3. The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit.

    Science.gov (United States)

    Vincent, Maxence S; Durand, Eric; Cascales, Eric

    2016-01-01

    The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.

  4. The PorX response regulator of the Porphyromonas gingivalis PorXY two-component system does not directly regulate the Type IX secretion genes but binds the PorL subunit.

    Directory of Open Access Journals (Sweden)

    Maxence S Vincent

    2016-08-01

    Full Text Available The Type IX secretion system (T9SS is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion of surface attachment of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY and PorX encode typical two-component system (TCS sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of the porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we showed that PorX does not bind and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.

  5. The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit

    Science.gov (United States)

    Vincent, Maxence S.; Durand, Eric; Cascales, Eric

    2016-01-01

    The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.

  6. The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit.

    Science.gov (United States)

    Vincent, Maxence S; Durand, Eric; Cascales, Eric

    2016-01-01

    The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS. PMID:27630829

  7. Suicidio por arma de fuego Suicide by firearm

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    M. Soriano Maldonado

    2005-01-01

    Full Text Available El mecanismo elegido para cometer el suicidio depende de numerosos factores personales y sociales. En este número presentamos una imagen del tipo de suicidio más mediático, aunque no por ello el más frecuente en nuestro medio. La variabilidad en la forma de los orificios de entrada y salida por arma de fuego depende de la distancia, tipo de arma y región anatómica por lo que puede presentar una morfología muy variada. Es por ello que, aunque ya se han publicado varias imágenes de suicidio por otro tipo de armas, aportamos un caso de suicidio típico por arma corta con especial descripción de las lesiones que se originan en cráneo.The mechanism chosen for suicide depends upon various personal and social factors. In this paper, we present an image of the more mediatic type suicide, although not the most frequent in our means. The variability in the entrance and exit orifices by firearm depends on the distance, type of weapon and anatomical region; for that reason they can present/display a wide morphology. Although several images of suicide by another type of arms have been published already, today we contributed with a case of typical suicide by handgun, paying special attention to the injuries affecting the skull.

  8. Pronóstico de la diarrea por rotavirus

    Directory of Open Access Journals (Sweden)

    Mota-Hernández Felipe

    2001-01-01

    Full Text Available Objetivo. Comparar la gravedad de la diarrea por rotavirus (RV y por no rotavirus. Material y métodos. Estudio transversal en 520 lactantes con diarrea aguda, efectuado entre octubre de 1994 y marzo de 1995 en siete centros del primer nivel de atención en cinco estados de México. El diagnóstico de RV se realizó con ensayo inmunoenzimático o por electroforesis. El análisis se hizo a través de medidas de tendencia central. Los resultados se presentan como promedio y desviación estándar o mediana o variación. Resultados. Se aisló RV en 264 lactantes (50.7% con predominio en varones de 6 meses a un año. Las manifestaciones clínicas fueron significativamente diferentes entre el grupo rotavirus positivo y el grupo rotavirus negativo en mediana de evacuaciones por 24 horas, frecuencia de vómitos, temperatura > 38° C, deshidratación y calificación de gravedad, respectivamente. Conclusiones. Estos resultados mostraron peor pronóstico por mayor gravedad de la diarrea por RV en lactantes, con relación a otra etiología. El texto completo en inglés de este artículo está disponible en: http://www.insp.mx/salud/index.html

  9. Neuropatia experimental por DDT: análise de nervo por microdissecção de fibras

    OpenAIRE

    Edison Matos Nóvak; Lineu Cesar Werneck

    1984-01-01

    Estudou-se o nervo gênito-femural do rato albino submetido a intoxicação crônica por DDT, administrado por 180 dias na dose de 5 mg/kg de peso via oral. Os resultados mostraram proporção anormal de fibras tipo C, sendo sugerido ocorrer degeneração tipo axonal determinada pelo DDT.

  10. Neuropatia experimental por DDT: análise de nervo por microdissecção de fibras

    Directory of Open Access Journals (Sweden)

    Edison Matos Nóvak

    1984-09-01

    Full Text Available Estudou-se o nervo gênito-femural do rato albino submetido a intoxicação crônica por DDT, administrado por 180 dias na dose de 5 mg/kg de peso via oral. Os resultados mostraram proporção anormal de fibras tipo C, sendo sugerido ocorrer degeneração tipo axonal determinada pelo DDT.

  11. Enxertia em figueira 'Roxo de Valinhos' por borbulhia e garfagem

    Directory of Open Access Journals (Sweden)

    Tailene Elisa Kotz

    2011-01-01

    Full Text Available Com o intuito de desenvolver um protocolo de enxertia em estacas não enraizadas de figueira 'Roxo de Valinhos' (Ficus carica L., foram realizados dois experimentos com aplicação de duas técnicas de propagação: borbulhia e garfagem. No primeiro experimento, estacas lenhosas de 20 cm de comprimento, coletadas da porção mediana dos ramos, de junho a setembro, foram enxertadas por borbulhia tipo placa e "T" normal. No segundo experimento, os propágulos foram coletados em julho e as estacas foram enxertadas pelo método da garfagem, imergindo-se metade das estacas em solução de 2.000 mg L-1 de AIB por 10 segundos e metade permaneceu como controle. Os enxertos foram protegidos com sacos plásticos transparentes (18 x 3 cm, mantidos por 0, 15, 30, 45 e 60 dias. Posteriormente, as estacas dos dois experimentos foram enterradas a 2/3 de seu comprimento em leito de areia, sob telado (sombrite com 50% de luminosidade. Aos 60 e 120 dias após a enxertia, mensuraram-se a porcentagem de borbulhas e garfos vivos, a porcentagem de borbulhas e garfos brotados, a porcentagem de borbulhas e garfos vivos em porta-enxertos enraizados e o comprimento médio da brotação do enxerto. Concluiu-se que a enxertia da figueira 'Roxo de Valinhos' pode ser efetuada por borbulhia, pelo método "T", e por garfagem, devendo-se efetuar a imersão das estacas em AIB e proteger os garfos por 60 dias.

  12. Seroprevalence and molecular biological investigation of commonly known Rickettsia species in rodents in Qujing Prefecture, Yunnan Province, China%云南省曲靖市啮齿动物的立克次体血清学和分子流行病学调查

    Institute of Scientific and Technical Information of China (English)

    章域震; 王勇; 杨卫红; 朱向晖; 皮自林; 冯云; 何丽芳; 张海林; 张丽娟

    2015-01-01

    目的 调查云南省曲靖市啮齿动物感染立克次体状况.方法 用鼠笼法捕鼠,采集鼠血清和脾脏.用间接免疫荧光试验(IFA)检测鼠血清中7种常见立克次体的IgG抗体;用巢氏PCR方法检测鼠脾中嗜单核细胞埃立克体和嗜吞噬细胞无形体16S rRNA基因片段部份序列.结果 2012年7-9月在曲靖市捕获啮齿动物3种592只,褐家鼠(Rattus norvegicus)和黄胸鼠(Rattus flavipectus)构成比分别为61.49%和35.47%.鼠血清中贝氏柯克斯体(Coxiella burentii)、莫氏立克次体(Rickettsia typhi)、恙虫病东方体(Orientia tsutsugamushi)、西伯利亚立克次体(Rickettsia sibirica)、嗜吞噬细胞无形体(Anaplasma phagocytophilum)和嗜单核细胞埃立克体(Ehrlichia chafeensis)的抗体阳性率依次为21.45%、7.60%、7.09%、3.38%、1.18%和0.51%;未检测到猫立克次体(Rickettsia felis)抗体.从5份褐家鼠脾脏标本中检测到16S rRNA基因序列,同源性和进化分析表明,1株为嗜吞噬细胞无形体,4株为莫氏立克次体.结论曲靖市啮齿动物中存在莫氏立克次体和人粒细胞无形体流行,褐家鼠可能是主要宿主;同时还存在恙虫病东方体、贝氏柯克斯体、斑点热立克次体和埃立克体的感染.当地疾控和医疗机构应加强立克次体病的监测.

  13. La responsabilidad del Estado por la actividad del legislador

    Directory of Open Access Journals (Sweden)

    María Consuelo Alonso García

    2012-12-01

    Full Text Available Analizar el fenómeno de la responsabilidad del Estado causada por los hechos del legislador ha sido un trabajo desarrollado tanto por la doctrina y la jurisprudencia internacional a mediados del siglo xx. En Francia, por ejemplo, se presentó el primer antecedente jurisprudencial en el año de 1934. En España, su estudio empezó a gestionarse con la promulgación de la Constitución de 1978, presentándose el primer fallo judicial en el año de 1993. Para el caso colombiano, la Constitución de 1991 introdujo en su artículo 90 el fundamento constitucional de la responsabilidad patrimonial del Estado, sin que esto significase que la jurisprudencia del Consejo de Estado encontrase las bases de esta responsabilidad en diferentes disposiciones de la Constitución. Sin embargo, los primeros fallos relacionados con este título de imputación en Colombia fueron emitidos por el máximo tribunal de lo contencioso administrativo en 1998, y por la Corte Constitucional a través de la sentencia C-038 de 2006, providencia judicial que estableció algunas de las características que posee esta figura jurídica.

  14. Riesgos antrópicos generados por la actividad minera

    Directory of Open Access Journals (Sweden)

    Ana Violeta Argüello Mejía

    2013-10-01

    Full Text Available Las actividades productivas generan riesgos antrópicos [1] a mediano y largo plazo. La zona de estudio se ubica en las Parroquias de Pomasqui, San Antonio y Calacalí, donde se han producido riesgos debido a las actividades humanas, en este caso, por la explotación de las canteras para abastecer el mercado de la construcción del Distrito Metropolitano de Quito. La investigación propone determinar los riesgos antrópicos generados por la actividad minera. Los pobladores de la zona identifican que la minería artesanal en sus inicios constituyó una fuente de trabajo, donde sus familias también se involucraban. Actualmente, se observa que en la mayoría de las canteras se utiliza maquinaria especializada y no participan los trabajadores de la zona. Los taludes de las canteras son de 80o y 90o grados, generando amenazas para los trabajadores y moradores de las viviendas aledañas. Uno de los mayores impactos es la contaminación del aire, sin embargo, el suelo y los cursos de agua están siendo afectados por los desperdicios que produce la actividad minera. La población, que está expuesta permanentemente al polvo ocasionado por las canteras y al transporte de material, acusa enfermedades de tipo respiratorio. Así mismo, el ruido ocasionado por el transporte constituye una molestia constante para los pobladores.

  15. Micetoma pulmonar por Scedosporium sp, reporte de dos casos

    Directory of Open Access Journals (Sweden)

    José G. Somocurcio

    2009-07-01

    Full Text Available Se reporta los dos primeros casos de micetoma pulmonar por Scedosporium sp, en el Perú, tratados quirúrgicamente en el Hospital Nacional Hipólito Unanue. Se practicó resección pulmonar debido a micetoma pulmonar de donde se tomó muestras que fueron enviadas a microbiología y anatomía patológica para cultivo y estudio histopatológico. Se identificó el moho Scedosporium sp en dos pacientes con secuelas cavitarias por tuberculosis, quienes presentaron tos y hemoptisis de dos meses y tres años de evolución, respectivamente. Radiológicamente las cavidades estaban ocupadas por una "bola fúngica". La histopatología indicó presencia de abundantes hifas, indistinguibles de las de Aspergillus sp, mientras que la inmunodifusión para Aspergillus fue negativa.

  16. Responsabilidad del empleador por accidentes de trabajo y enfermedades profesionales

    Directory of Open Access Journals (Sweden)

    Cristina Mangarelli

    2014-01-01

    Full Text Available Introducción. 1. Responsabilidad del “empleador” por accidentes de trabajo y enfermedades profesionales. Noción. 2. La indemnización “tarifada”. Fundamento de su procedencia 3. Responsabilidad del empleador por accidentes de trabajo o enfermedades profesionales en la ley uruguaya (ley Nº 16.074. 4. La “ampliación” de la responsabilidad del empleador por el derecho común en el derecho uruguayo (artículo 7 ley Nº 16.074. 5. Requisitos para la ampliación de la responsabilidad patronal: culpa grave en el incumplimientode normas de seguridad y prevención. 6. La culpa grave. Concepto. 7. El modelo del hombre a tener en cuenta en la “culpa grave” no es el del buen padre de familia. 8. El grado de la culpa no puede ser medido por el resultado del accidente. 9. Se aplican las eximentes de la responsabilidad civil. 10. Distintos ámbitos de la responsabilidad patronal por accidentes de trabajo o enfermedades profesionales: A ante la víctima o los derecho-habientes; B ante el Banco de Seguros del Estado; C ante el Ministerio de Trabajo ySeguridad Social. 11. Recupero del BSE en caso de culpa grave en el incumplimiento de normas de seguridad y prevención. Requisitos 12. Responsabilidad del empleador en caso de accidente de trabajo o enfermedad profesional sufrido por un adolescente. Conclusiones.

  17. La responsabilidad del Estado por el hecho del legislador

    Directory of Open Access Journals (Sweden)

    María Consuelo Alonso

    2011-12-01

    Full Text Available Analizar el fenómeno de la responsabilidad del Estado causada por los hechos del legislador ha sido un trabajo desarrollado tanto por la doctrina como por la jurisprudencia internacional a mediados del siglo xx. En Francia, por ejemplo, se presentó el primer antecedentejurisprudencial en el año de 1934. En España, su estudio empezó a gestionarse con la promulgación de la Constitución de 1978, dándose el primer fallo judicial en el año de 1993. Para el caso colombiano, la Constitución de 1991 introdujo en su artículo 90 el fundamento constitucional de la responsabilidad patrimonial del Estado, sinque esto significase que la jurisprudencia del Consejo de Estado encontrase las bases de esta responsabilidad en diferentes disposiciones de la Constitución de 1886, tales como los artículos 2º, 16 y 30, que consagró el principio de legalidad del Estado para proteger la vida, honra y bienes de los ciudadanos, y garantizar la propiedad privada y los demás derechos adquiridos con el título de derecho. Sin embargo, los primeros fallos relacionados con este título de imputación en Colombia fueron emitidos por el máximo Tribunal de lo Contencioso Administrativo colombiano en el año de 1998 y por la Corte Constitucional a través de la Sentencia C-038 de 2006, providencia judicial que estableció algunas de las características que posee esta figura jurídica.

  18. Varmetransport i evakuerede porøse materialer

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe

    Indlægget omhandlede varmetransport i porøse materialer (ledning, konvektion og stråling) under atmosfæretryk og under vacuum. Specielt omhandlede præsentationen også silica aerogel som et eksempel på et højporøst isoleringsmateriale.......Indlægget omhandlede varmetransport i porøse materialer (ledning, konvektion og stråling) under atmosfæretryk og under vacuum. Specielt omhandlede præsentationen også silica aerogel som et eksempel på et højporøst isoleringsmateriale....

  19. Neumonitis por hipersensibilidad en la ciudad de México

    Directory of Open Access Journals (Sweden)

    Carrillo-Rodríguez José G.

    2000-01-01

    Full Text Available OBJETIVO: Determinar la asociación entre la zona urbana de origen del paciente en la ciudad de México y la prevalencia de neumonitis por hipersensibilidad inducida por antígeno aviario. MATERIAL Y MÉTODOS: Se trata de un estudio de casos y controles realizado en el Instituto Nacional de Enfermedades Respiratorias, en la ciudad de México, en el año de 1999. Se estudiaron 109 casos con neumonitis por hipersensibilidad y 184 controles: de éstos, 39, con fibrosis pulmonar idiopática; 63, con tuberculosis pulmonar, y 82, con asma. La ciudad de México y las zonas conurbadas se dividieron en cinco zonas geográficas: centro, noreste, sureste, noroeste y el suroeste. Se calcularon las prevalencias de las diferentes enfermedades por zona urbana de los pacientes que participaron en el estudio; como medida de asociación, se estimó la razón de momios, con un intervalo de confianza al 95%. Asimismo, se realizó regresión logística múltiple ajustando por edad, sexo y estrato socioeconómico. RESULTADOS: Ochenta casos de neumonitis por hipersensibilidad se concentraron en el sur del noreste de las zonas conurbadas y la parte norte del sureste de la ciudad de México, 48 y 32, respectivamente (RM= 3.86, IC 95% 2.17-6.96. Treinta y seis controles de asma se localizaron en el suroeste de la ciudad de México, zona donde se ubica el Intituto Nacional de Enfermedades Respiratorias (p<0.05 y cuatro en la zona conurbada. Los controles de tuberculosis pulmonar y fibrosis pulmonar idiopática estuvieron dispersos en la ciudad de México y en las zonas conurbadas. CONCLUSIONES: La zona sur del noreste y el norte de la sureste están asociadas a la neumonitis por hipersensibilidad. Las causas de esta asociación no parece ser geográfica, pero existe el antecedente de que esa zona fue basurero de la ciudad, por lo que partículas orgánicas en el ambiente pudieran coadyuvar a la aparición de esta enfermedad.

  20. Efecto de la quercetina sobre la nefrotoxicidad producida por cadmio

    OpenAIRE

    A. I. Morales Martín; Vicente Sánchez; C. Santiago Sandoval; J Mª Fernández Tagarro; J.M. López Novoa; F. Pérez Barriocanal

    2004-01-01

    El incremento en la producción anual de cadmio ha favorecido que la incidencia de la intoxicación crónica por este elemento haya aumentado en los últimos años. El estrés oxidativo es uno de los mecanismos implicados en la generación del efecto tóxico, manifestándose, entre otras patologías, por una disfunción y lesión renal. La quercetina, un flavonoide muy abundante en la dieta mediterránea, es un potente antioxidante y un buen quelante de metales. Nuestro objetivo fue estudia...

  1. As comunidades de Porífera do litoral Norte

    OpenAIRE

    Pereira, Tânia Ribeiro

    2007-01-01

    Os indivíduos do filo Porifera possuem um papel essencial nas comunidades bentónicas, não só por serem animais filtradores e detritívoros, como pelo facto de estabelecerem relações simbióticas com vários organismos, nomeadamente algas, e servirem de abrigo e alimento a muitos animais. A estrutura das comunidades Porifera é influenciada por vários factores ambientais, entre os quais os padrões de sedimentação, a velocidade da corrente, e o tamanho e inclinação do substrato. D...

  2. Mujeres procesadas por el Tribunal del Santo Oficio de Granada

    OpenAIRE

    Pérez de Colosía Rodríguez, María Isabel

    2005-01-01

    Actualmente, la Historiografía se ha visto enriquecida gracias a los estudios realizados acerca de las mujeres. Muchos son los aspectos que pueden tratarse al respecto, dada la abundancia de fuentes. En la documentación inquisitorial encontramos un rico filón relativo al tema, que presenta dos aspectos bien diferenciados. Por un lado tenemos a las familiares del personal civil del Santo Oficio, que gozaban de una serie de privilegios. Por otro están aquellas que sufrieron las p...

  3. Infecciones por adenovirus en Cuba (2000-2008)

    OpenAIRE

    González Muñoz, Grehete

    2013-01-01

    Las infecciones por adenovirus causan un variado espectro clínico en el hombre, con un rango que incluye desde la infección asintomática hasta la enfermedad diseminada con peligro para la vida. En el presente estudio, se analizó el comportamiento de las infecciones por adenovirus en síndromes de etiología viral como la infección respiratoria aguda, la miocarditis viral, la conjuntivitis hemorrágica y el síndrome neurológico infeccioso. Además, se estudió la participación de estos agentes en l...

  4. Guía por las lindes transilvanas

    Directory of Open Access Journals (Sweden)

    Rafael Guillermo Serrano

    1998-04-01

    Full Text Available Paul EluardRecorrer ahora el territorio dejado por Bram Stoker y su novela Drácula -a cien años de su primera edición- resulta sin duda caminar por las alucinantes fronteras del mundo delirante del vampiro como el hijo con- sentido de la nocturnidad y de las sombras. Aunque el terreno abonado es significativo, convocamos aquí un breve merodeo en relación con el tema en la literatura y su cuota de realidad; agregamos como postre un grupo de poemas y la conseja para prevenir la visita del vampiro.

  5. La educación por competencias en ciencias naturales

    OpenAIRE

    Mendoza Aguirre, F.; Rodríguez-Pineda, D.

    2009-01-01

    Si bien existen programas de actualización docente, en el ámbito de las Ciencias Naturales dentro de la “Educación por Competencias”, la mayoría de las instituciones que ofrecen capacitación, lo hacen sólo desde el “saber” -conocimiento-, dejando de lado el “saber hacer” y el “saber ser”. El hecho de dejar fuera dos componentes fundamentales de las competencias produce una visión distorsionada en los docentes, la cual hace crisis cuando llegan al aula ha implementar la enseñanza por competenc...

  6. Signos Vitales de los CDC-Muertes por intoxicación por alcohol (Alcohol Poisoning Deaths)

    Centers for Disease Control (CDC) Podcasts

    2015-01-06

    Este podcast se basa en la edición de enero del 2015 del informe Signos Vitales de los CDC. En los Estados Unidos, mueren en promedio seis personas cada día debido a la intoxicación por alcohol. Infórmese sobre lo que puede hacer para prevenir los atracones de alcohol y las intoxicaciones por alcohol.  Created: 1/6/2015 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 1/6/2015.

  7. Levantamiento del proceso de registros contables por causación de las cuentas por cobrar a clientes

    OpenAIRE

    Mayele-Rodríguez, Luz

    2013-01-01

    De igual forma el Proyecto de Mejora de Procesos a elaborar, desarrollar e implementar en el Área Administrativa y Financiera del Centro de Pinturas Automotriz “LMS”, es realizar el levantamiento del Proceso de Registros Contables por Causación de las cuentas por cobrar a clientes. Lo anterior se puede desarrollar a partir de un poder de negociación con proveedores que incluye entre otros los siguientes factores : El plazo alcanzado en la negociación de compras de insumos, materias primas, co...

  8. Exploración dirigida por el objetivo en Aprendizaje por Refuerzo Basado en Modelo para ambientes no estacionarios

    OpenAIRE

    Errecalde, Marcelo Luis; Muchut, Alfredo

    2001-01-01

    El Aprendizaje por Refuerzo Basado en Modelo (ARBM) es una extensión al Aprendizaje por Refuerzo tradicional en la que el agente aprende una política (comportamiento), y en forma simultánea aprende un modelo de su ambiente. Distintos estudios han mostrado la superioridad de los métodos de ARBM sobre los métodos libres de Modelo en ambientes estacionarios. Sin embargo, existen serias dificultades para adaptar los métodos de ARBM a ambientes no estacionarios, existiendo actualmente un único mét...

  9. System design description for portable 1,000 CFM exhauster Skids POR-007/Skid E and POR-008/Skid F

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, O.D.

    1998-07-25

    The primary purpose of the two 1,000 CFM Exhauster Skids, POR-007-SKID E and POR-008-SKID F, is to provide backup to the waste tank primary ventilation systems for tanks 241-C-106 and 241-AY-102, and the AY-102 annulus in the event of a failure during the sluicing of tank 241-C-106 and subsequent transfer of sluiced waste to 241-AY-102. This redundancy is required since both of the tank ventilation systems have been declared as Safety Class systems.

  10. Identification of Porphyromonas gingivalis proteins secreted by the Por secretion system.

    Science.gov (United States)

    Sato, Keiko; Yukitake, Hideharu; Narita, Yuka; Shoji, Mikio; Naito, Mariko; Nakayama, Koji

    2013-01-01

    The Gram-negative bacterium Porphyromonas gingivalis possesses a number of potential virulence factors for periodontopathogenicity. In particular, cysteine proteinases named gingipains are of interest given their abilities to degrade host proteins and process other virulence factors such as fimbriae. Gingipains are translocated on the cell surface or into the extracellular milieu by the Por secretion system (PorSS), which consists of a number of membrane or periplasmic proteins including PorK, PorL, PorM, PorN, PorO, PorP, PorQ, PorT, PorU, PorV (PG27, LptO), PorW and Sov. To identify proteins other than gingipains secreted by the PorSS, we compared the proteomes of P. gingivalis strains kgp rgpA rgpB (PorSS-proficient strain) and kgp rgpA rgpB porK (PorSS-deficient strain) using two-dimensional gel electrophoresis and peptide-mass fingerprinting. Sixteen spots representing 10 different proteins were present in the particle-free culture supernatant of the PorSS-proficient strain but were absent or faint in that of the PorSS-deficient strain. These identified proteins possessed the C-terminal domains (CTDs), which had been suggested to form the CTD protein family. These results indicate that the PorSS is used for secretion of a number of proteins other than gingipains and that the CTDs of the proteins are associated with the PorSS-dependent secretion. PMID:23075153

  11. Validade por processo de resposta no teste de Cloze

    Directory of Open Access Journals (Sweden)

    Neide de Brito Cunha

    2009-12-01

    Full Text Available Tendo por base considerações sobre as evidências de validade por processo de resposta, foram analisados neste estudo os erros cometidos num teste de Cloze. Participaram 266 crianças, de ambos os sexos, entre 8 e 13 anos, de terceiras e quartas séries do Ensino Fundamental de escolas públicas e particulares de São Paulo. Foram formados dois grupos de protocolos: das crianças que tiveram as melhores e as piores pontuações, para a construção de uma escala dos tipos de erros cometidos, a saber: branco, fonológico, lexical, sintático e semântico. Os resultados mostraram que as crianças com médias mais altas cometeram mais erros lexicais e as com médias mais baixas, erros semânticos. Embora tenha sido encontrada a evidência de validade por processo de resposta, por meio da avaliação da homogeneidade na distribuição dos tipos de erros, é preciso ampliar o conhecimento sobre as características psicométricas do teste de Cloze.

  12. Enoftalmos unilateral por várice orbitaria

    Directory of Open Access Journals (Sweden)

    Ricardo J. Smith

    2014-04-01

    Full Text Available El enoftalmos es un motivo de consulta poco frecuente en la práctica médica. La mayor parte de los casos se debe a un aumento de la cavidad ósea orbitaria de origen traumático. Presentamos el caso de una mujer de 63 años que consultó por enoftalmos progresivo de su ojo izquierdo, de doce años de evolución. El examen oftalmológico reveló la presencia de un marcado enoftalmos del lado izquierdo, que mejoraba notablemente con maniobras de Valsalva. Una tomografía computarizada y una resonancia magnética de la órbita permitieron diagnosticar una várice orbitaria no complicada. Las várices orbitarias son infrecuentes y por lo general se manifiestan por episodios de exoftalmos intermitente. Sin embargo, en raras ocasiones, la distensión y colapso repetidos pueden llevar a un enoftalmos progresivo por atrofia de la grasa orbitaria.

  13. Centros oncológicos designados por el NCI

    Science.gov (United States)

    El programa de centros oncológicos designados por el Instituto Nacional del Cáncer (NCI) reconoce a los centros de todo el país que cumplen con rigurosos criterios para participar en proyectos avanzados de primer nivel para la investigación multidisciplinaria del cáncer.

  14. Disminuyen en los Estados Unidos las infecciones por VPH.

    Science.gov (United States)

    La infección por los tipos del virus del papiloma humano (VPH) en el blanco de la vacuna cuadrivalente se redujo en casi dos tercios en las adolescentes desde que se recomendó la vacunación en los Estados Unidos.

  15. Muerte cerebral causada por consumo de psicofármacos

    OpenAIRE

    Iglesias Rozas, José Rafael, 1942-

    1987-01-01

    Tres imágenes de una biopsia de un cerebro en estado de muerte cerebral causada por consumo de psicofármacos. Three pictures of a biopsy of a brain that has died because of consumption of psychoactive drugs.

  16. Analisis cualitativo asistido por computadora Computer-assisted qualitative analysis

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    César A. Cisneros Puebla

    2003-01-01

    Full Text Available Los objetivos de este ensayo son: por un lado, presentar una aproximación a la experiencia hispanoamericana en el Análisis Cualitativo Asistido por Computadora (ACAC al agrupar mediante un ejercicio de sistematización los trabajos realizados por diversos colegas provenientes de disciplinas afines. Aunque hubiese querido ser exhaustivo y minucioso, como cualquier intento de sistematización de experiencias, en este ejercicio son notables las ausencias y las omisiones. Introducir algunas reflexiones teóricas en torno al papel del ACAC en el desarrollo de la investigación cualitativa a partir de esa sistematización y con particular énfasis en la producción del dato es, por otro lado, objetivo central de esta primera aproximación.The aims of this article are: on the one hand, to present an approximation to the Hispano-American experience on Computer-Assisted Qualitative Data Analysis (CAQDAS, grouping as a systematization exercise the works carried out by several colleagues from related disciplines. Although attempting to be exhaustive and thorough - as in any attempt at systematizing experiences - this exercise presents clear lacks and omissions. On the other hand, to introduce some theoretical reflections about the role played by CAQDAS in the development of qualitative investigation after that systematization, with a specific focus on data generation.

  17. El dilema del consenso por superposición rawlsiano

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    Vergés Gifra, Joan

    2004-12-01

    Full Text Available In this paper we present an objection against the idea of overlapping consensus, nuclear to John Rawls political liberalism. The objection can be put in a dilemmatic form: either an overlapping consensus plays no significant role when it comes to justify the two principles of the conception of justice as fairness, or such idea presupposes the acceptation of some traits or concepts particular to a comprehensive liberalism.

    En este trabajo presentamos una objeción al liberalismo político de John Rawls. La objeción puede formularse en forma de un dilema que afecta especialmente a la noción de consenso por superposición: o bien el consenso por superposición no ofrece ninguna razón categórica o justificativa a favor de los dos principios de justicia rawlsianos y, por tanto, es irrelevante, o bien tal noción presupone la aceptación de determinados caracteres o conceptos propios de un liberalismo comprehensivo y, por consiguiente, la concepción de la justicia como equidad no es tan política como Rawls sugiere.

  18. Trombocitopenia induzida por heparina Heparin-induced thrombocytopenia

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    Fernanda Longhi

    2001-08-01

    Full Text Available O objetivo deste relato é fazer uma revisão a fim de obter informações atualizadas sobre trombocitopenia induzida por heparina, suas manifestações clínicas, seu diagnóstico e seu manejo terapêutico. Após, concluímos que a trombocitopenia induzida por heparina é uma complicação comum em pacientes submetidos a tratamento com heparina, indiferentemente da doença de base. Complicações trombóticas potencialmente fatais têm sido descritas. Por essa razão, se houver suspeita de trombocitopenia induzida por heparina, uma abordagem adequada incluindo suspensão precoce da heparina é mandatória. Produtos que substituem a heparina incluem hirudina e danaparóide sódico. Heparina de baixo peso molecular é contra-indicada.The aim of this paper is to review current information about the clinical manifestations, diagnosis and management of heparin-induced thrombocytopenia. This was achieved by a bibliographic review using Public Medline and consulting Hematology textbooks. From this study we concluded that heparin-induced thrombocytopenia is a common complication of patients exposed to heparin therapy regardless of underlying conditions. Potentially fatal thrombotic complications have been reported. Therefore, if heparin-induced thrombocytopenia is suspected, an adequate approach including early heparin discontinuation is mandatory. Alternative products for heparin include hirudin and danaparoid sodium. Low-molecular-weight heparin is contraindicated.

  19. Reacciones radicalarias de epoxicetonas insaturadas inducidas por titanoceno

    OpenAIRE

    Mateos Burón, Lydia

    2010-01-01

    [ES]Tesis doctoral sobre Reacciones radicalarias de epoxicetonas insaturadas inducidas por titanoceno, perteneciente al departamento de química orgánica [EN]Doctoral Thesis on the radical reactions induced by unsaturated titanocene epoxicetonas, from the organic chemistry´s departament

  20. Mortalidad por envenenamiento en niños

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    Híjar Martha

    1998-01-01

    Full Text Available Objetivo. Conocer el panorama de las muertes por envenenamiento en niños de 0-14 años ocurridas en la República mexicana, entre 1979 y 1994. Material y métodos. Se utilizaron fuentes secundarias. Las variables analizadas fueron: edad, sexo, año, causa externa de traumatismos y envenenamientos, de la IX Clasificación Internacional de Enfermedades: E850-E858, E860-E869 y E905. Mediante un modelo de regresión Poisson se analizaron tendencias por causa específica y se obtuvieron riesgos relativos según edad, sexo y entidad federativa. Resultados. Hubo un total de 11 272 defunciones en menores de 15 años; las principales causas fueron el envenenamiento y las reacciones tóxicas causadas por plantas y animales venenosos (E905, el envenenamiento accidental por gas de uso doméstico y por monóxido de carbono (E868 y el envenenamiento accidental por otras drogas (E858. El grupo de edad que presentó los mayores riesgos, para las causas mencionadas, fue el de menores de un año con un riesgo relativo (RR de 29.6, IC95% 29.2-33.4; RR 3.47, IC95% 2.86-4.22, y RR 31.86, IC95% 24.8-40.9. El riesgo fue similar en ambos sexos, salvo para la causa E905. El estado de Aguascalientes se situó sistemáticamente entre los de mayor riesgo para todas las causas analizadas, mientras que Nuevo León siempre se ubicó entre los de riesgo más bajo. Conclusiones. El envenenamiento constituye una importante causa de muerte en los niños; el riesgo se incrementa al disminuir la edad. Considerando que esas muertes son potencialmente evitables y que la mayor parte de los envenenamientos ocurren en el hogar, para prevenirlos, se recomienda a los familiares vigilar y mantener fuera de peligro al niño. Por otra parte, la multicausalidad del fenómeno requiere que su prevención se realice desde una perspectiva multidisciplinaria que genere una cultura y un ambiente de seguridad en la sociedad.

  1. Morbilidad oculta por parasitismo intestinal en Lagunita, municipio Girardot, Venezuela

    Directory of Open Access Journals (Sweden)

    Yanelis Núñez Gómez

    2014-08-01

    Full Text Available Se realizó un estudio epidemiológico descriptivo de corte transversal, con el objetivo de determinar la morbilidad oculta por parasitismo intestinal en Lagunita, municipio Girardot, Venezuela; en el período de enero a octubre de 2009. El universo fue de 286 niños, lo que se corresponde con la población total del grupo de edad de menores de 15 años. De estos se seleccionaron por muestreo aleatorio simple 43 pacientes, a los que se les aplicó un cuestionario y se confeccionó una guía de observación, para describir los factores epidemiológicos que influyen en la infestación por parasitismo intestinal. Además, se les realizaron análisis de las heces fecales seriadas para el diagnóstico del parasitismo. El método estadístico fue el cálculo de las frecuencias absolutas y relativas. A través del estudio de las heces fecales seriadas se obtuvo que 27 pacientes tenían parasitosis intestinal, para una morbilidad de 62,79%, con una mayor incidencia en los niños de cinco a nueve años de edad. El sexo femenino fue el más afectado. Los factores epidemiológicos que más influyeron fueron: los malos hábitos higiénicos personales, el entorno desfavorable y el consumo de agua no potable; existió relación entre el nivel socioeconómico, los factores epidemiológicos y la morbilidad por parasitismo intestinal. Predominó la parasitosis por Entamoeba Histolytica, con 11 casos, para un 40,74%. La diarrea, las molestias abdominales y la pérdida de apetito constituyeron los principales síntomas

  2. LUCHA POR LA TIERRA EN EL NORTE DE URUGUAY

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    Gabriel Oyhantçabal Benelli

    2011-12-01

    Full Text Available Este artículo analiza la trayectoria de la lucha por la tierra en Bella Unión, una región característica en Uruguay por la producción de caña de azúcar, a través de los movimientos de clase de sus principales protagonistas: los cortadores de caña sindicalizados en la Unión de Trabajadores Azucareros de Artigas (UTAA. El recorrido histórico hace énfasis en dos períodos históricos diferentes: 1961-1973 y 2005-presente. El primero va desde la fundación del sindicato hasta el golpe militar. Se da en un contexto de auge de la lucha de masas en Uruguay en el cual los trabajadores rurales se organizan en la UTAA levantando, entre otras, la bandera de la Reforma Agraria. El segundo período está marcado por la llegada al gobierno nacional del Frente Amplio, una coalición social-demócrata que reactiva la producción de caña de azúcar en Bella Unión. Este cambio supone una oportunidad para las luchas sociales que la UTAA aprovecha con ocupaciones de tierra favoreciendo un proceso de colonización para los trabajadores rurales. Sin embargo el acceso a la tierra genera nuevas contradicciones, y por tanto nuevos desafíos, por los cambios en la forma de subsunción del trabajo al capital.

  3. CARACTERÍSTICAS DA VIOLÊNCIA SEXUAL SOFRIDA POR CRIANÇAS ASSISTIDAS POR UM PROGRAMA DE APOIO

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    KELLY LINHARES VASCONCELOS

    2010-01-01

    Full Text Available En Brasil, las estadísticas de la violencia sexual contra niños están lejos de reflejar la verdadera realidad actual debido a la baja notificación de los casos. La finalidad de este estudio fue caracterizar el abuso sexual sufrido por niños asistidos por el Programa Sentinela y el perfil del agresor, en Sobral-Ceará, en el periodo que va del 2002 al 2006. La muestra no probabilística intencional fue compuesta por 50 víctimas de abuso sexual y de las mismas, el 66% es del sexo femenino, con predominio de rango de edad entre 8-12 años incompletos, (58%; en el 36% de los casos los padres están separados, siendo la madre la principal responsable por la familia (62%. La mayoría de los agresores es del sexo masculino (78%. En el ambiente fuera de la familia los agresores son conocidos o amigos de la familia (14%; dentro del seno familiar el padrastro es identificado como siendo el agresor más frecuente (18%. Los datos destacan características similares a las de otros estudios, definiendo una cierta igualdad en este tipo de violencia.

  4. Os desdobramentos internacionais do desenvolvimento e da demanda por petróleo na China, por Diego Pautasso

    OpenAIRE

    DIEGO PAUTASSO

    2009-01-01

    Esteartigoaborda a crescente demanda da
    China por petróleo e seus desdobramentos internacionais.
    O argumento central équea política externa
    e a economia da China têm fornecidoumaresposta
    ativa à dependência de petróleo com consequênciasimportantes
    parao reordenamento mundial.

  5. Vivencias psicosociales reveladas por niños que reciben tratamiento con quimioterapia por cáncer

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    BLANCA CECILIA VANEGAS DE AHOGADO

    2009-12-01

    Full Text Available Se realizó un estudio cualitativo con el propósito de descubrir las vivencias psicosociales de niños y niñas de 9 a 12 años que recibían tratamiento con quimioterapia por cáncer. La recolección de la información se hizo mediante encuentros lúdicos con el apoyo de algunas preguntas básicas que facilitaron las revelaciones narrativas. Tres aspectos se destacan en los hallazgos del estudio: vivencias desfavorables, vivencias relacionadas con la autoestima y vivencias favorables; las dos primeras, de diversa manera, afectan en estos niños su vida personal, familiar, escolar y, en general, todo su entorno. Es de resaltar que, como consecuencia de la caída del cabello, con frecuencia han sido objeto de burla y de rechazo por sus compañeros de estudio, lo que produce el más notorio efecto sobre su autoimagen; por otra parte, el ausentismo escolar conlleva dificultades académicas y sentimientos de tristeza en estos niños, situación que empeora cuando, por motivos de tratamiento, su lugar de residencia está alejado de la ciudad, viéndose sometidos a largos periodos de separación, no solo de su familia sino de sus pares. Se concluye que la mayor parte de las revelaciones son impactantes por su gran contenido de sufrimiento y dolor para estos niños, lo que demuestra la urgencia de retomar los hallazgos del estudio para orientar el cuidado de enfermería de manera más integral y apoyar para que se haga lo propio en el hogar y en las instituciones educativas.

  6. 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.

  7. Candida albicans skin abscess Abscesso de pele por Candida albicans

    Directory of Open Access Journals (Sweden)

    Felipe Francisco Tuon

    2006-10-01

    Full Text Available Subcutaneous candidal abscess is a very rare infection even in immunocompromised patients. Some cases are reported when breakdown in the skin occurs, as bacterial cellulites or abscess, iatrogenic procedures, trauma and parenteral substance abuse. We describe a case of Candida albicans subcutaneous abscess without fungemia, which can be associated with central venous catheter.Abscesso subcutâneo por Candida é infecção muito rara mesmo em pacientes imunocomprometidos. Alguns casos são relatados quando ocorre dano na pele, como celulite bacteriana ou abscesso, procedimentos iatrogênicos, trauma e abuso de substância parenteral. Relatamos caso de abscesso subcutâneo por Candida albicans sem fungemia, que pode estar associado com cateter venoso central.

  8. Calidad percibida por el espectador de fútbol

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    Isabel Mar\\u00EDa Rosa D\\u00EDaz

    2012-01-01

    Full Text Available Para lograr competitividad, las organizaciones se esfuerzan por comprender las necesidades de sus clientes, con el fin de satisfacerlas adecuadamente. En esta línea, en el ámbito de la gestión deportiva se ha iniciado un caminocuyo objetivo consiste en crear medidas específicas de la calidad del servicio y la satisfacción del cliente. Este es el contexto en el que se enmarca la presente investigación, cuyo objetivo fundamental consisteen determinar las dimensiones de la calidad del servicio deportivo ofrecido por los clubes de fútbol. Para ello se ha aplicado un cuestionario a través del método de la encuesta personal. Los datos obtenidos han sido tratados mediante un análisis factorial exploratorio. Los resultados permiten identificar diez dimensiones básicas de la calidad del servicio deportivo analizado.

  9. Optimizacion del talento en las organizaciones gestion por expectativas

    OpenAIRE

    Castilla Sánchez, Antonio

    2013-01-01

    La gestión del talento es en la actualidad un ámbito de estudio propio de la dirección de empresas y más concretamente, de las Direcciones de RR.HH, que ha despertado el interés de académicos del ámbito de la psicología de las organizaciones en las últimas décadas. La tesis que se presenta, “optimización del talento en las organizaciones: Gestión por expectativas”, nos ofrece un viaje por la realidad de una organización mediante un estudio etnográfico, llevado a cabo en una empresa de serv...

  10. Neuropatia Óptica Tóxica causada por Dissulfiram

    OpenAIRE

    Lemos, José Alberto; Ribeiro, Isabel; Martins, João; Menezes, Carlos; Gonçalves, Rita; Coelho, Pedro; Maio, Tiago

    2015-01-01

    Objetivos: O dissulfiram é utilizado no tratamento do alcoolismo crónico há mais de 50 anos. Este fármaco interfere no metabolismo do etanol e encoraja a abstinência por causar sintomas desagradáveis com a ingestão concomitante de álcool. Efeitos adversos incluem casos raros de neuropatia óptica bilateral. O objetivo deste artigo é descrever um caso clínico de neuropatia óptica tóxica causada por dissulfiram. Métodos: Descrição do caso clínico e breve revisão bibliográfica. Resultados: Report...

  11. Diagnóstico auxiliado por computador na radiologia

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    Azevedo-Marques Paulo Mazzoncini de

    2001-01-01

    Full Text Available Vários desenvolvimentos tecnológicos estão convergindo de forma a aumentar a influência da área de imagens nas pesquisas biomédicas e na medicina clínica. Muitos pesquisadores têm trabalhado no desenvolvimento de sistemas computadorizados para detecção automatizada e quantificação de anormalidades em imagens radiológicas. Estes sistemas são dedicados ao diagnóstico auxiliado por computador. Este artigo discute os conceitos básicos relacionados ao diagnóstico auxiliado por computador e apresenta uma revisão bibliográfica sobre o assunto.

  12. LUCHA POR LA TIERRA EN EL NORTE DE URUGUAY

    OpenAIRE

    Gabriel Oyhantçabal Benelli; Matías Carámbula Pareja

    2011-01-01

    Este artículo analiza la trayectoria de la lucha por la tierra en Bella Unión, una región característica en Uruguay por la producción de caña de azúcar, a través de los movimientos de clase de sus principales protagonistas: los cortadores de caña sindicalizados en la Unión de Trabajadores Azucareros de Artigas (UTAA). El recorrido histórico hace énfasis en dos períodos históricos diferentes: 1961-1973 y 2005-presente. El primero va desde la fundación del sindicato hasta el golpe militar. Se d...

  13. Hugo Grocio: la guerra por medio del derecho

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    Javier Peña Echeverría

    2014-01-01

    Full Text Available La posición de Grocio respecto a la guerra es considerada en este artículo como un intento de mediación entre el realismo político y el moralismo pacifista. Aunque la guerra es una consecuencia inevitable del conflicto permanente en las relaciones humanas, puede ser ajustada a los principios y reglas del derecho natural común a los hombres y del derecho de gentes resultante del consenso entre los pueblos. En consecuencia, Grocio expone las condiciones de justificación de la guerra y propone reglas de conducta en la guerra. Sin embargo, persiste una tensión insuperable entre las pretensiones normativas de la moral y el derecho, por un lado, y la lógica de la fuerza propia de la guerra, por otro.

  14. El riego por chorro intermitente: un sistema prometedor

    Directory of Open Access Journals (Sweden)

    Hernando Buriticá

    2011-10-01

    Full Text Available A través de la historia el hombre se ha ingeniado varios sistemas para suplir las deficiencias de agua que las condiciones naturales de clima han impuesto para el desarrollo de la agricultura: desvió ríos, construyó canales y reservorios y entregó el agua a los cultivos empleando variados sistemas de riego. En este caso haremos referencia al riego por chorro intermitente.

  15. Herstellung und Charakterisierung hoch poröser nanostrukturierter Filtermembranen

    OpenAIRE

    Mertler, Michael

    2007-01-01

    In dieser Arbeit wurden hoch poröse, nanostrukturierte Filtermembranen untersucht und ihre Eigenschaften charakterisiert. Diese Nanomembranen bieten einen erfolgversprechenden Ansatz zur Minimierung der Haftkräfte von stark adhäsiven Stäuben auf der Membranoberfläche. Dies wird einerseits durch die Verringerung der Korngrößen der Nanomembranen und andererseits durch die Bereitstellung von nur wenigen Kontaktstellen auf der Nanomembran angestrebt. Die Nanomembranen wurden als Beschichtung d...

  16. Glucogeno sintasa en helmintos parasitos: inhibicion por benzimidazoles

    OpenAIRE

    H. Gomez-Banqueri; M. A. Garcia Ruiz; M. Monteoliva; Sanchez-Moreno, M.

    1987-01-01

    Se ha determinado el effecto inhibidor sobre la actividad Glucogeno sintetasa (E.C.2.41.11) por parte de cuatro antihelminticos: Albendazol, Mebendazol, Parbendazol y Tiabendazol. Observandose que en todos los casos, es el Parbendazol quien ha demostrado un mayor poder inhibidor sobre la glucógeno sintetasa de Ascaris suum, Fasciola hepatica y Moniezia expansa. El Tiabendazol es el anti-helmintico que menor efecto inhibidor ha presentado sobre la enzima en los tres parasitos objeto de nuestro...

  17. Estrategias de mercadeo verde utilizadas por empresas a nivel mundial

    Directory of Open Access Journals (Sweden)

    Castellano, Susie

    2015-09-01

    Full Text Available La preocupación por el medio ambiente se ha convertido en una temática que inquieta a toda la colectividad actual, desde los más pequeños hasta los más grandes, desde la pequeña empresa hasta la gran industria. Sumado a esto, el auge de normativas ambientales que establecen regulaciones al empresario, los obliga a tener una mayor conciencia de los daños que pueden causar sus acciones al medio ambiente. Es por esto, que paulatinamente ha comenzado, por parte de las empresas, la adopción de estrategias en el área de mercadeo verde que les permita comercializar sus productos y servicios de forma que los mismos sean ambientalmente compatibles. En el presente trabajo, se abordaron las diferentes estrategias que han venido asumiendo empresas de diferente índole para hacer frente a tan importante filosofía en el ámbito mundial. Para tal fin, se hizo la revisión y contrastación de artículos escritos en el marco del mercadeo verde por Rivera y Molero (2006, Chamorro (2001, Samper y Echeverri (2008 principalmente, encontrándose que cada vez son más las empresas que se suman a esta forma de mercadear sus procesos y productos y más los consumidores que anteponen criterios ecológicos ante variables de otra índole, modificando sus hábitos de consumo.

  18. RESPONSABILIDAD INTERNACIONAL DEL ESTADO COLOMBIANO POR ACCIONES DE GRUPOS PARAMILITARES

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    Nataly Vargas Ossa

    2008-12-01

    Full Text Available El Sistema Interamericano constituye un espacio que permite observar la situación de los Derechos Humanos en América Latina, los mecanismos de protección a que acuden las víctimas y la actitud de los Estados frente a la promoción, protección y defensa de los Derechos Humanos. Bajo esta premisa es que el proyecto “Alcance y Descripción de los Derechos Humanos en el Sistema Interamericano de Protección de los Derechos Humanos”, utilizando el método dogmático documental, pretendió recopilar aquellas providencias que permiten recoger el concepto y el alcance que La Corte Interamericana ha desarrollado entorno a algunos Derechos Humanos, es así como el presente escrito hace parte de los resultados de dicho proyecto, el cual recopila las sentencias proferidas por la Corte Interamericana en contra del Estado Colombiano, por acciones de grupos paramilitares.El estado Colombiano en reiteradas oportunidades ha sido declarado internacionalmente responsable por violaciones a Derechos Humanos, debido a la conformación y apoyo de grupos “paramilitares“. En el presente escrito se busca retomar aquellas providencias emanadas de la Corte Interamericana, en lo que tiene que ver con la descripción y alcance de derechos por los cuales el Estado Colombiano ha sido condenado. En es orden de ideas son cuatro providencias objeto análisis del presente escrito: El Caso de los 19 Comerciantes, el Caso de la Masacre de Mapiripán, el Caso de las Masacres de Pueblo Bello, y el Caso de las Masacres de Ituango.

  19. Hepatotoxicidad inducida por azatioprina en paciente con enfermedad de Crohn

    Directory of Open Access Journals (Sweden)

    D. Ruiz-Clavijo

    2013-08-01

    Full Text Available Los inmunosupresores se encuentran entre los grupos farmacológicos con mayor potencial teórico de inducir reacciones adversas, entre ellas las hepáticas. Presentamos el caso de un paciente de 35 años con enfermedad de Crohn en tratamiento con azatioprina por corticodependencia al que se le diagnosticó tras realización de una biopsia hepática de hiperplasia nodular regenerativa secundaria a este tratamiento.

  20. Enfoque por competencias, ¿una respuesta al fracaso escolar?

    Directory of Open Access Journals (Sweden)

    Philippe Perrenooud

    2009-01-01

    Full Text Available Son tiempos de reflexión sobre las competencias. Queda mucho por investigar acerca de sus posibilidades pero es cierto que, desde el punto de vista teórico, el enfoque por competencias se presenta como potente al complementar una pedagogía que, tradicionalmente, se ha centrado en las disciplinas y en los saberes. Pero también este enfoque aparece fuerte en el campo de la formación en la medida en que viene vinculado a las prácticas sociales y educativas, al trabajo pedagógico de los problemas educativos en las diferentes situaciones, a los proyectos que los educadores desean materializar en sus lugares de trabajo. Están por demostrar las expectativas puestas en el enfoque por competencias y este texto trata de pensar toda una serie de cuestiones relacionadas con su puesta en marcha en los contextos formativos.---------------------------------------------------------------------These are times for reflection on skills. There is much left to investigate on their possibilities but it is true that, from the theoretical point of view, the skill approach appears to be powerful by complementing a pedagogy which, tradicionally, has focused on the knowledge and disciplines. But this approach appears strongly in the training field as it is linked to the social and educational practices, to the pedagogic work on educative problems, to the different situations, to the project that teachers wish to materialize in the labor places. Still to be demonstrated are the expectations on the skills approach, and this text tries to think on a series of matters related with its set in motion in the learning contexts.

  1. Se evitaron casi 800 000 muertes por descenso del tabaquismo

    Science.gov (United States)

    Programas y estrategias de control del tabaco del siglo XX fueron responsables de la prevención de más de 795 000 muertes por cáncer de pulmón en Estados Unidos de 1975 al 2000. Si todo el tabaquismo en este país hubiera cesado después de la publicación d

  2. Perforación intestinal por un palillo de dientes

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    Marvin Yglesias-Rosales

    2006-10-01

    Full Text Available Existe una gran variedad de cuerpos extraños que son deglutidos por los seres humanos, entre los cuales son numerosos los que pueden producir una perforación del tracto gastrointestinal. Se enfocará esta discusión en los palillos de dientes, caso particular, por poseer 2 extremos puntiagudos, lo que hace se consideren como portadores de una gran morbimortalidad. El espectro de manifestaciones clínicas asociado con las lesiones por palillos de dientes ingeridos es muy amplio; el diagnóstico de perforación del tracto gastrointestinal por cuerpo extraño es difícil de realizar en el pre-operatorio, ya que la mayoría de los pacientes no recuerdan haber ingerido algún cuerpo extraño. El pronóstico del paciente depende del diagnóstico oportuno, así como del tipo de abordaje, de las comorbilidades del paciente y de las complicaciones que refiera. Se presenta aquí el caso de un hombre con perforación ileal secundaria a la ingesta de 1palillo de dientes y que fue manejado con éxito. El diagnóstico diferencial del abdomen agudo, o lo que es más, del dolor abdominal agudo, es difícil, ya que en un espacio reducido se encuentran numerosas vísceras, con un variado repertorio de enfermedades cada una y con un limitado espectro de síntomas. En cuanto a los cuerpos extraños, la situación se complica todavía más, pues pueden afectar diferentes órganos y presentar una clínica intrascendente, posibilidad diagnóstica que hay que tener en mente al valorar un dolor abdominal.

  3. Riesgos por Legionella, Prevención y Control

    OpenAIRE

    Martín Romero, Magdalena

    2014-01-01

    Para un buen control de riesgos por Legionella pneumophila, es importante conocer con detalle esta bacteria, los efectos que causa en el hombre, las principales fuentes de contagio y los medios para evitarlo. Este es el objetivo del presente trabajo. La legionelosis a pesar de ser percibida como una enfermedad infecciosa potencialmente erradicable, se puede controlar con medidas higiénico- sanitarias en las instalaciones implicadas.

  4. HOSPITALIZACIONES EVITABLES POR INSUFICIENCIA CARDÍACA. VARIABLES RELACIONADAS

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    Victoria Ruiz-Romero

    2016-01-01

    Full Text Available Los ingresos hospitalarios evitables por insuficiencia cardiaca (IC son un problema para los sistemas de salud, consumen recursos, generan morbilidades adicionales y alta mortalidad. El objetivo del estudio fue conocer los factores de riesgo de las personas hospitalizadas por insuficiencia cardiaca. Métodos: Se constituyó un grupo con médicos de atención primaria y hospitalaria. Se realizaron auditorías de las historias clínicas de 110 pacien - tes de la poblacion de la comarca del Aljarafe con mayores tasas de ingreso por insuficiencia cardiaca y estudio descriptivo y comparativo con T-Student y U-Mann Whitney para cuantitativas y λ 2 y Fisher para cualitativas. Resultados: Los pacientes que ingresaron por IC tenían 78,1 años (SD: 9,56 de media; 73 (66,4% fueron mujeres; un Índice Barthel de 45,0 de media; un 53,5% con grado III de la NYHA y 17 (15,5% institucionaliza - dos. El 70% presentaban 3-5 comorbilidades, hipertensión (87,3%, dislipe - mia (60,0% diabetes (57,3%, enfermedad renal crónica (56,4%, anemia (53,2% o fibrilación auricular (52,7%. Fallecieron al ingreso 23 (20,9% pacientes. Conclusiones: Los ingresos se dieron en personas mayores con múl - tiples enfermedades (hipertensión, diabetes, EPOC, enfermedad renal y escasa capacidad para actividades básicas de la vida diaria. El fallecimiento hospitalario se asoció a edad avanzada, ser mujer, menor uso de betabloqueantes y la no inclusión del paciente en el proceso asistencial.

  5. por Penicillium digitatum: ¿se equivocaba Janzen?

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    J.E. Peris

    2015-01-01

    Full Text Available Janzen (1977 propuso que los vertebrados frugívoros prefieren los frutos sanos frente a los infectados por hongos y bacterias dado que los microbiosproducen compuestos tóxicos y antibióticos y, además, reducen el valor nutritivo de los frutos infectados. Valoramos dicha hipótesis mediante experimentosde campo en los que ofrecimos tres variedades comerciales de frutos del género Citrus sanos e infectados por Penicillium digitatum.Sorprendentemente, los frugívoros (principalmente conejos Oryctolagus cuniculus y roedores como la rata negra Rattus rattus y ratones, probablemente,Mus spretus y Apodemus sylvaticus prefirieron siempre los cítricos infectados a los frutos "control" sanos. En concreto, el consumo de frutosinfectados de las tres variedades estudiadas fue hasta 32 veces mayor en comparación con el consumo de frutos sanos. Proponemos tres hipótesisno excluyentes que podrían explicar la preferencia de los frutos infectados por mamíferos y otros vertebrados frugívoros.

  6. Uso de contraceptivos por puérperas adolescentes

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    Fernanda Schulz da Rosa

    2014-07-01

    Full Text Available Objetivo: Indagar el uso de métodos contraceptivos por las puérperas adolescentes a fin de relacionar su (desuso con el embarazo en la adolescencia. Método: Estudio transversal, descriptivo, realizado por medio de un instrumento estructurado con 181 puérperas adolescentes que tuvieron sus partos en el hospital participante de la investigación. Los datos fueron recolectados en el período de diciembre de 2008 a diciembre de 2009. Resultados: El 64,1% de las puérperas usaba algún método contraceptivo antes del embarazo; los métodos más utilizados fueron el anticoncepcional oral (51% y el preservativo masculino (29%. Para el 75% de las adolescentes el embarazo fue planeado y justificado por el deseo y la voluntad propia de experimentar la maternidad. Conclusión: Considerando que casi la mitad de las adolescentes entrevistadas deseaba el embarazo, se deduce que investigar y discutir apenas el uso o no de los métodos contraceptivos no es adecuado. Es necesario profundizar las investigaciones acerca de los significados de ser madre en la adolescencia.

  7. Diagnostico por PCR del complejo Sigatoka en Colombia.

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    Romero Magally

    1999-06-01

    Full Text Available Las Sigatokas negra y amarilla son enfermedades causadas por Mycosphaerella fijiensis y Mycosphaerella musicola respectivamente. Estas dos especies de hongos estrechamente relacionadas y morfológicamente similares, causan necrosis severa en las hojas de banano y plátano disminuyendo el área de tejido fotosintético y acelerando la maduración del fruto. Las enfermedades producidas por estos hongos afectan la mayoría de las áreas cultivadas de banano y plátano a nivel mundial, generando un gran problema económico y ambiental. Los síntomas que produce cada uno de estos patógenos en el cultivo son similares, por lo que su correcta identificación en campo se hace difícil. Con el fin de hacer una identificación precisa de cada uno de ellos decidimos estandarizar una prueba diagnóstica basada en la reacción en cadena de la polimerasa (PCR utilizando dos oligonucleótidos de 21 bases (MF 137 y MM 137 específicos para cada una de las especies M. fijiensis y M. musicola respectivamente. MF 137 y MM 137 codifican regiones variables identificadas en las secuencias interespaciadoras (ITS del DNA ribosomal.

  8. Extracción de sustancias asistida por ultrasonido (EUA

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    Rocío Azuola

    2007-11-01

    Full Text Available Compuestos presentes en los vegetales con propiedades funcionales o tecnológicas, han cobrado gran importancia en los mercados de alimentos, farmacéuticos y cosméticos. Se buscan métodos eficientes, económicos y favorables al ambiente para la extracción de estas sustancias. Se ha realizado un estudio bibliográfico de las publicaciones recientes sobre diferentes métodos de extracción y su comparación a las extracciones asistidas por ultrasonido (EAU con el fin de evaluar su eficacia y viabilidad industrial. Se ha encontrado que la EAU es más eficiente que los métodos de extracción tradicionales, y más económica y sencilla que los métodos de extracción no tradicionales como la extracción asistida por microondas, por lo cual se comprueba su viabilidad industrial.

  9. Confirmación por laboratorio de leptospirosis: laboratory confirmation

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    María De los Ángeles Valverde-Jiménez

    2008-03-01

    Full Text Available Se presenta el caso de un joven de quince años de edad que consulta a un hospital privado por enfermedad febril aguda de origen desconocido, asociada a elevación discreta de transaminasas y otras alteraciones inespecíficas de los exámenes de laboratorio. Fue referido para observación a un hospital de la Caja Costarricense de Seguro Social, donde se le maneja como cuadro de dengue clásico. La atención en la clínica privada se restableció luego de su egreso, se confirmó el diagnóstico de leptospirosis por parte del laboratorio del Centro Nacional de Referencia de Leptospirosis del iNCIENSA y se manejó con antibióticos hasta su resolución. El artículo enfatiza la importancia del diagnóstico de la leptospirosis mediante un alto grado de sospecha, una historia clínica precisa, un buen examen fisico y la confirmación diagnóstica por laboratorio con el fin de tratarla apropiadamente.

  10. Por una antropología de las emociones

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    David Le Breton

    2012-12-01

    Full Text Available En este texto, se analiza el carácter social de las emociones y la importancia de los contextos cul‐ turales en las encarnaciones y formas de experimentar el sentir afectivamente. Primero se discute la perspectiva naturalista del estudio de las emociones. Como se sostiene, los sentimientos y las emociones no son sustancias transferibles ni de un individuo ni de un grupo a otro, y no son sólo procesos fisiológicos. Son relaciones, y por tanto son el producto de una construcción social y cul‐ tural, y se expresan en un conjunto de signos que el hombre siempre tiene la posibilidad de des‐ plegar, incluso si no las sienten. La emoción es a la vez interpretación, expresión, significación, re‐ lación, regulación de un intercambio; se modifica de acuerdo con el público, el contexto, se diferencia en su intensidad, e incluso en sus manifestaciones, de acuerdo a la singularidad de cada persona. Como se argumenta, el individuo añade su nota en un patrón colectivo susceptible de ser reconocido por los pares (de acuerdo con su historia personal, psicología, estatus social, sexo, edad, etc. La afectividad es el impacto de un valor personal que se enfrenta a un contexto tal y como es experimentado por el individuo.. 

  11. El principio general de reductio ad aequitatem por desequilibrio contractual

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    José Félix Chamie

    2012-06-01

    Full Text Available Para atender las exigencias del mundo actual se requiere de la proposición de categorías dogmáticas que contribuyan en el desarrollo del sistema jurídico unificando conceptos, simplificando caminos interpretativos, y sobre la base de la propia tradición rediseñar instrumentos para mejorar el derecho poniéndolo a tono con las exigencias de su tiempo. De allí la intención del autor de aventurarse en una reconstrucción histórico-dogmática de figuras bien conocidas por la tradición del sistema jurídico romano-germánico, en aras de identificar un principio de moderación en los contratos. Un principio de equilibrio que desde los tiempos de la Escuela medieval se contiene en la expresión reductio ad aequitatem y se realiza mediante instrumentos que procuran corregir y adaptar el contrato según el caso. Así, el autor se fija en los momentos de la celebración y de la ejecución del contrato para observar la ratio de los institutos que en esos momentos del iter contractual sirven la causa de la equidad para ajustar la sinalagmaticidad de la relación, contrastar abusos y desequilibrios causados por las partes o por eventos extraños al riesgo del contrato.

  12. DE ACUMULACIÓN POR DESPOSESIÓN

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    Sebastián Gómez Lende

    2015-01-01

    Full Text Available Omnipresente, la acumulación por desposesión es uno de los elementos centrales del orden global contemporáneo. Observados desde una perspectiva crítica, los usos extractivos del territorio constituyen una de las principales expresiones de ese proceso. A la luz de ese sistema de ideas, este artículo procura demostrar que el modelo sojero actualmente vigente en la Argentina es una de las formas más completas, exhaustivas, actuales y sofisticadas, de acumulación por desposesión en el país. En ese sentido, el artículo analiza el boom de la soja transgénica y sus vínculos con las formas tanto seculares (endeudamiento financiero, concentración de la propiedad rural, usurpación de la tierra y actuales de desposesión (degradación de la naturaleza, despojo del derecho a la salud, pillaje de recursos genéticos efectuadas por los grandes agricultores, el capital financiero, las agroindustrias y las corporaciones biotecnológicas, en detrimento de los pequeños productores, los campesinos, los pueblos aborígenes y la población en general.

  13. GRAVIDADE DE INTOXICAÇÕES POR SANEANTES CLANDESTINOS

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    Jessica Adrielle Teixeira Santos

    2011-01-01

    Full Text Available El presente estudio tuvo como objetivo analizar las intoxicaciones por saneantes comercializados clandestinamente, reportadas en el Centro de Control de Intoxicaciones del Hospital Universitario Regional de Maringá. Es un estudio cuantitativo, con análisis retrospectivo de registros epidemiológicos de personas intoxicadas por estos agentes, en el período de enero de 2005 a diciembre de 2009. De los 118 casos reportados, la mayoría (74-62,7% se produjeron en varones, 105 (88,9% necesitaron de asistencia en unidades de atención de emergencia y hospitalización de alta complejidad, en 14 casos (11,8% requirieron de Cuidados Intensivos, y se reportaron cinco óbitos, todos por intoxicación intencional. Los resultados demuestran la gravedad y la letalidad de este tipo de intoxicación, sugieren la necesidad de medidas urgentes de fiscalización y control de la Vigilancia Sanitaria, así como de medidas para la educación de los consumidores, haciendo hincapié en el papel educativo de la Enfermería

  14. Pseudoobstrucción intestinal por Ascaris lumbricoides

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    Alessio Garro Donini

    2015-12-01

    Full Text Available La ascariosis es una geohelmintosis, ya que el agente causal requiere de la tierra para que se forme la fase infectiva para el hombre, que en este caso la fase es el huevo larvado conteniendo la larva de segundo estadio. Es una infección producida por el nematodo Ascaris lumbricoides, uno de los parásitos descritos desde la antigüedad (Becerril, 2008. Esta parasitosis tiene gran importancia epidemiológica, pues las zonas donde se presenta con mayor frecuencia son las de gran pobreza; aquellas donde la gente acostumbra a defecar a ras del suelo, pues no tiene el recurso económico necesario para construir baños, ni dispone de agua potable. Esta parasitosis afecta a 25 a 35% de la población mundial (Biagi, 2004 (Becerril, 2008. Generalmente los pacientes infectados por este nematodo cursan asintómaticos, pero en caso contrario la sintomatología dependerá de la fase del ciclo vital en la que el parásito se encuentre pudiendo existir síntomas pulmonares o gastrointestinales, incluso en ciertas poblaciones como la pediátrica podría incluso ocasionar la muerte por múltiples mecanismos dentro de los cuales se incluyen la migración errática y/o la obstrucción intestinal (MS., 1996

  15. Reliable Data Delivery in MANETs Using POR Protocol

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    B. Sunil Kumar

    2013-03-01

    Full Text Available This balance addresses the company of release matter packets for stage sprightly mercurial beating the drum hoc networks in a reliable and timely manner. Most suitable verifiable propaganda hoc routing protocols are susceptible to node mobility, especially for large-scale networks. Dominated by this topic, we clench an apt Position-based Exploitive Routing (POR rite which takes give a reason for of the stateless acquiring of geographic routing and the broadcast nature of wireless medium. At the drop of a hat a information collection is sent about, several of the neighbor nodes stray shot overheard the publish resoluteness satisfy as alteration lawn, and round play the part to prepay the package dispatch if it is whine relayed by the specific best forwarder within a certain period of time. By utilizing such in-the-air every other, message is maintained without being interrupted. The bells latency incurred by inbred tour improvement is broadly tuppence inexpensively and the replica relaying caused by packet reroute is also decreased. In the scrap of notice opening, a Look up Destination-based Delete Comport (VDVH desire is in the deep-freeze proposed to work together with POR. Both outline enquiry and affectedness benefits show mosey POR achieves superior achievement unruffled here brazen node mobility with acceptable overhead and the new void handling scheme also works well

  16. Por que rir da Filosofia Política?: Abertura

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    Lessa Renato

    1998-01-01

    Full Text Available As diferentes intervenções que compuseram este debate têm como referência comum uma reflexão sobre os lugares da Filosofia Política na tradição disciplinar que designamos como Ciência Política. Recusando a perspectiva que dissocia a Filosofia Política da dimensão empiricamente orientada da disciplina, os argumentos apresentados destacam o papel de fertilização de formas de vida cumprido pela primeira. A agenda dos pesquisadores devotados à boa faina da investigação empírica foi, e segue sendo, em grande medida definida e configurada por exercícios prévios de invenção social e política e por decisões de ordem ontológica, epistemológica e retórica. Neste sentido, a distinção entre ciência e filosofia é, além de obscurantista e marcada por enorme otimismo epistemológico, sintoma de um desconhecimento forte com relação à história do conhecimento político.

  17. Consumo de carnes por adolescentes do Sul do Brasil

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    Maria Cecília Formoso Assunção

    2012-08-01

    Full Text Available OBJETIVO: Descrever a frequência de consumo de diferentes tipos de carnes conforme variáveis sociodemográficas e nutricionais, e analisar o consumo, em adolescentes do Sul do Brasil, de dieta rica em gordura conforme os tipos de carne consumidos. MÉTODOS: Estudo transversal realizado com adolescentes pertencentes à coorte de nascimentos de 1993, em Pelotas (RS. A frequência de consumo de carnes vermelhas, brancas, vísceras e embutidos foi avaliada por um Questionário de Frequência de Consumo Alimentar, adaptado para este estudo. A ingestão de dieta rica em gordura foi avaliada a partir do instrumento proposto por Block. As variáveis independentes foram sexo, cor da pele, nível socioeconômico, escolaridade materna e estado nutricional. Nas análises estatísticas, foram utilizados testes Qui-quadrado de heterogeneidade e de tendência linear. RESULTADOS: Foram avaliados 4.325 adolescentes com idade média de 14,7, DP=0,3 anos, dos quais 51,2% eram do sexo feminino. A frequência de consumo diário de carnes vermelhas foi maior do que a de carnes brancas (43,0% e 9,7%, respectivamente. O consumo de embutidos por mais do que quatro vezes por semana foi referido por 48,5% dos indivíduos, e 81,4% relataram consumir vísceras raramente ou nunca. Adolescentes de maior nível socioeconômico e filhos de mães com maior escolaridade apresentaram maior consumo de carnes vermelhas e embutidos, enquanto aqueles em situação oposta apresentaram maior consumo de carnes brancas. Adolescentes que consomem carnes com maior frequência também consomem dieta rica em gordura. CONCLUSÃO: As carnes consumidas com maior frequência pelos adolescentes foram as vermelhas e os embutidos. No entanto, adolescentes de maior nível socioeconômico consomem carnes vermelhas com maior frequência, enquanto adolescentes menos favorecidos economicamente consomem mais carnes brancas.

  18. Maculopatia tóxica por cloroquina Chloroquine toxic maculopathy

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    Nikias Alves da Silva

    2009-06-01

    Full Text Available O fosfato de cloroquina é uma droga largamente utilizada no tratamento de doenças crônicas de autoagressão, mais comumente no controle da artrite reumatóide, do lupus eritematoso discóide ou disseminado, da porfiria cutânea, da urticária solar e outras afecções dermatológicas. Embora a incidência de toxicidade retiniana por esta droga seja baixa, mesmo com o emprego da dose máxima recomendada, sua ocorrência tem grande relevância por acometer a região macular com importante e irreversível comprometimento visual. Trata-se no presente caso de uma paciente de 44 anos, portadora de artrite reumatóide há 19 anos, que fez uso de fosfato de cloroquina na dose de 250 mg/dia durante dois períodos de 4 e 3 anos, intercalados por um período de 8 anos em que usou methotrexate. Ao final do segundo período de uso da cloroquina, foi observada a maculopatia, a partir de quando a droga foi definitivamente substituída por methotrexate e prednisona. Por seu caráter típico e conspícuo, a maculopatia em questão se presta muito bem para ilustrar os achados dos principais métodos propedêuticos que devem ser empregados para caracterizá-la, inclusive a tomografia de coerência óptica.Chloroquine phosphate is widely used for the treatment of chronic autoimune diseases, most commonly rheumatoid arthritis, discoid or disseminated lupus erythematous, light sensitivity eruptions as well as other dermatologic affections. Although the incidence of retinal toxicity by this drug is low even with the maximally recomended dose, its occurrence is relevant because it damages the macula with an important and irreversible visual impairment. A 44-year-old white female patient who had suffered from rheumatoid arthritis for about 19 years had been under treatment with chloroquine phosphate in the daily dose of 250 mg during two periods of 4 and 3 years, intercalated by an 8-year period of methotrexate usage. At the end of the 3-year period, a maculopathy

  19. Intoxicação por monofluoroacetato em animais

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    Vivian Assunção Nogueira

    2011-10-01

    Full Text Available O monofluoroacetato (MF ou ácido monofluoroacético é utilizado na Austrália e Nova Zelândia no controle populacional de mamíferos nativos ou exóticos. O uso desse composto é proibido no Brasil, devido ao risco de intoxicação de seres humanos e de animais, uma vez que a substância permanece estável por décadas. No Brasil casos recentes de intoxicação criminosa ou acidental têm sido registrados. MF foi identificado em diversas plantas tóxicas, cuja ingestão determina "morte súbita"; de bovinos na África do Sul, Austrália e no Brasil. O modo de ação dessa substância baseia-se na formação do fluorocitrato, seu metabólito ativo, que bloqueia competitivamente a aconitase e o ciclo de Krebs, o que reduz produção de ATP. As espécies animais têm sido classificadas nas quatro Categorias em função do efeito provocado por MF: (I no coração, (II no sistema nervoso central (III sobre o coração e sistema nervoso central ou (IV com sintomatologia atípica. Neste trabalho, apresenta-se uma revisão crítica atualizada sobre essa substância. O diagnóstico da intoxicação por MF é realizado pelo histórico de ingestão do tóxico, pelos achados clínicos e confirmado por exame toxicológico. Uma forma peculiar de degeneração hidrópico-vacuolar das células epiteliais dos túbulos uriníferos contorcidos distais tem sido considerada como característica dessa intoxicação em algumas espécies. O tratamento da intoxicação por MF é um desafio, pois ainda não se conhece um agente capaz de reverte-la de maneira eficaz; o desfecho geralmente é fatal

  20. Predominant porB1A and porB1B genotypes and correlation of gene mutations with drug resistance in Neisseria gonorrhoeae isolates in Eastern China

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    Tang Renxian

    2010-11-01

    Full Text Available Abstract Background Variations of porB1A and porB1B genes and their serotypes exist in Neisseria gonorrhoeae isolates from different geographical areas, and some site mutations in the porB1B gene correlate with drug resistance. Methods The β-lactamase production of N. gonorrhoeae isolates was determined by paper acidometric test and nitrocefin discs. The porB1A and porB1B genes of 315 non-penicillinase-producting N. gonorrhoeae (non-PPNG strains were amplified by PCR for sequencing to determine serotypes and site mutations. A duplex PCR was designed to simultaneously detect both porB1A and porB1B genes. Penicillin and tetracycline resistance was assessed by an in vitro drug sensitivity test. Results Of the N. gonorrhoeae isolates, 31.1% tested positive for porB1A and 68.9% for porB1B genes. All the 98 porB1A+ isolates belonging to IA6 serotype with either no mutation at the 120 and 121 sites (88.8% or a D120G (11.2% mutation and were no resistance to both penicillin and tetracycline. Among the 217 porB1B+ isolates, 26.7%, 22.6% and 11.5% belonged to IB3, IB3/6 and IB4 serotypes, respectively. Particularly, two novel chimeric serotypes, IB3/6-IB2 and IB2-IB4-IB2, were found in 77 and 8 porB1B+ isolates. Two hundred and twelve (97.7% of the porB1B+ isolates were presented G120 and/or A121 mutations with 163 (76.9% at both sites. Interestingly, within the 77 porB1B+ isolates belonging to IB3/6-IB2 serotype, 15 were discovered to possess novel deletions at both A121 and N122 sites. All the replacement mutations at these sites in PorB1B were correlated with resistance and the deletion mutation showed the highest resistance. Conclusion N. gonorrhoeae isolates circulating in Eastern China include a sole PorB1A serotype (IA6 and five PorB1B serotypes. Multiple mutations in porB1B genes, including novel A121 and N122 deletions, are correlated with high levels of penicillin and tetracycline resistance.