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1.
Foods ; 10(1)2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-33466255

RESUMEN

In this manuscript, we describe a new approach to study the effect of the eating environment on food intake and eating behavior using virtual reality technology. Fifteen adults consumed pizza rolls in two virtual reality (VR) environments: a restaurant and a table in an empty room. The participants' food intake, eating parameters (e.g., masticatory parameters and eating rate), and their sensory evaluation of the test food was measured. The participants' sense of presence (the feeling of being in the virtual environment) and markers of arousal were also measured. There was no statistical significant difference in food intake or the sensory evaluation of the test food. In the restaurant condition, participants used fewer masticatory cycles before swallowing but there was no effect on eating rate or maximum bite force. Participants experienced a greater sense of presence when they were in the pizza restaurant scene. Moreover, their heart rate and skin temperature were higher in the restaurant condition. This study suggests that VR could be developed as a new tool to study the effect of the eating environment on food intake and eating behavior.

2.
Front Neuroinform ; 10: 36, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27601990

RESUMEN

Brain research typically requires large amounts of data from different sources, and often of different nature. The use of different software tools adapted to the nature of each data source can make research work cumbersome and time consuming. It follows that data is not often used to its fullest potential thus limiting exploratory analysis. This paper presents an ancillary software tool called BRAVIZ that integrates interactive visualization with real-time statistical analyses, facilitating access to multi-facetted neuroscience data and automating many cumbersome and error-prone tasks required to explore such data. Rather than relying on abstract numerical indicators, BRAVIZ emphasizes brain images as the main object of the analysis process of individuals or groups. BRAVIZ facilitates exploration of trends or relationships to gain an integrated view of the phenomena studied, thus motivating discovery of new hypotheses. A case study is presented that incorporates brain structure and function outcomes together with different types of clinical data.

4.
Parasit Vectors ; 9: 68, 2016 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-26846867

RESUMEN

BACKGROUND: Out of 20 spirochete species from Borrelia burgdorferi sensu lato (s.l.) complex recognized to date some are considered to have a limited distribution, while others are worldwide dispersed. Among those are Borrelia burgdorferi sensu stricto (s.s.) and Borrelia bissettii which are distributed both in North America and in Europe. While B. burgdorferi s.s. is recognized as a cause of Lyme borreliosis worldwide, involvement of B. bissettii in human Lyme disease was not so definite yet. FINDINGS: Multilocus sequence typing of spirochete isolates originating from residents of Georgia and Florida, USA, revealed the presence of two Borrelia burgdorferi sensu stricto strains highly similar to those from endemic Lyme borreliosis regions of the northeastern United States, and an unusual strain that differed from any previously described in Europe or North America. Based on phylogenetic analysis of eight chromosomally located housekeeping genes divergent strain clustered between Borrelia bissettii and Borrelia carolinensis, two species from the B.burgdorferi s.l. complex, widely distributed among the multiple hosts and vector ticks in the southeastern United States. The genetic distance analysis showed a close relationship of the diverged strain to B. bissettii. CONCLUSIONS: Here, we present the analysis of the first North American human originated live spirochete strain that revealed close relatedness to B. bissettii. The potential of B. bissettii to cause human disease, even if it is infrequent, is of importance for clinicians due to the extensive range of its geographic distribution.


Asunto(s)
Borrelia/clasificación , Borrelia/aislamiento & purificación , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/microbiología , Tipificación de Secuencias Multilocus , Borrelia/genética , Borrelia burgdorferi , Grupo Borrelia Burgdorferi , Análisis por Conglomerados , Florida , Genes Esenciales , Genotipo , Georgia , Humanos , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Spirochaetales
5.
Vector Borne Zoonotic Dis ; 16(1): 13-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26783940

RESUMEN

Reaction of vertebrate serum complement with different Borrelia burgdorferi sensu lato species is used as a basis in determining reservoir hosts among domesticated and wild animals. Borrelia burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii were tested for their sensitivity to sera of exotic vertebrate species housed in five zoos located in the Czech Republic. We confirmed that different Borrelia species have different sensitivity to host serum. We found that tolerance to Borrelia infection possessed by hosts might differ among individuals of the same genera or species and is not affected by host age or sex. Of all zoo animals included in our study, carnivores demonstrated the highest apparent reservoir competency for Lyme borreliosis spirochetes. We showed that selected exotic ungulate species are tolerant to Borrelia infection. For the first time we showed the high tolerance of Siamese crocodile to Borrelia as compared to the other studied reptile species. While exotic vertebrates present a limited risk to the European human population as reservoirs for the causative agents of Lyme borreliosis, cases of incidental spillover infection could lead to successful replication of the pathogens in a new host, changing the status of selected exotic species and their role in pathogen emergence or maintenance. The question if being tolerant to pathogen means to be a competent reservoir host still needs an answer, simply because the majority of exotic animals might never be exposed to spirochetes in their natural environment.


Asunto(s)
Borrelia burgdorferi/fisiología , Proteínas del Sistema Complemento/farmacología , Enfermedad de Lyme/veterinaria , Vertebrados/inmunología , Animales , Animales de Zoológico , Reservorios de Enfermedades , Femenino , Enfermedad de Lyme/inmunología , Enfermedad de Lyme/microbiología , Masculino
6.
Parasit Vectors ; 7: 538, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25430588

RESUMEN

BACKGROUND: Analysis of Borrelia burgdorferi ospC types from the southeastern U.S.A. supported the common belief that various ospC types are geographically restricted and host specific. Being widely distributed in the region, the southeastern population of B. burgdorferi is represented by a surprisingly small number of ospC types. Types B, G and H are dominant or common and are invasive, while scarce type L, restricted mostly to the southeastern U.S.A., is believed to rarely if ever cause human Lyme disease. OspC type B and L strains are represented in the region at the same rate, however their distribution among tick vectors and vertebrate hosts is unequal. FINDINGS: Direct diagnostics was used to analyze the ability of B. burgdorferi ospC type L strains to disseminate into host tissues. Mice were infected by subcutaneous injections of B. burgdorferi strains of various ospC types with different invasive capability. Spirochete levels were examined in ear, heart, bladder and joint tissues. Noninfected I. ricinus larvae were fed on infected mice until repletion. Infection rates were determined in molted nymphs. Infected nymphs were then fed on naïve mice, and spirochete transmission from infected nymphs to mice was confirmed. CONCLUSIONS: B. burgdorferi ospC type L strains from the southeastern U.S.A. have comparable potential to disseminate into host tissues as ospC types strains commonly associated with human Lyme disease in endemic European and North American regions. We found no difference in the invasive ability of ospC type B and L strains originated either from tick vectors or vertebrate hosts.


Asunto(s)
Antígenos Bacterianos/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Borrelia burgdorferi/fisiología , Enfermedad de Lyme/microbiología , Animales , Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Borrelia burgdorferi/clasificación , Europa (Continente)/epidemiología , Femenino , Regulación Bacteriana de la Expresión Génica/fisiología , Humanos , Enfermedad de Lyme/epidemiología , Ratones , Sudeste de Estados Unidos/epidemiología
7.
Parasit Vectors ; 7: 4, 2014 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-24383476

RESUMEN

BACKGROUND: The controversy surrounding the potential impact of birds in spirochete transmission dynamics and their capacity to serve as a reservoir has existed for a long time. The majority of analyzed bird species are able to infect larval ticks with Borrelia. Dispersal of infected ticks due to bird migration is a key to the establishment of new foci of Lyme borreliosis. The dynamics of infection in birds supports the mixing of different species, the horizontal exchange of genetic information, and appearance of recombinant genotypes. METHODS: Four Borrelia burgdorferi sensu lato strains were cultured from Ixodes minor larvae and four strains were isolated from Ixodes minor nymphs collected from a single Carolina Wren (Thryothorus ludovicianus). A multilocus sequence analysis that included 16S rRNA, a 5S-23S intergenic spacer region, a 16S-23S internal transcribed spacer, flagellin, p66, and ospC separated 8 strains into 3 distinct groups. Additional multilocus sequence typing of 8 housekeeping genes, clpA, clpX, nifS, pepX, pyrG, recG, rplB, and uvrA was used to resolve the taxonomic status of bird-associated strains. RESULTS: Results of analysis of 14 genes confirmed that the level of divergence among strains is significantly higher than what would be expected for strains within a single species. The presence of cross-species recombination was revealed: Borrelia burgdorferi sensu stricto housekeeping gene nifS was incorporated into homologous locus of strain, previously assigned to B. americana. CONCLUSIONS: Genetically diverse Borrelia strains are often found within the same tick or same vertebrate host, presenting a wide opportunity for genetic exchange. We report the cross-species recombination that led to incorporation of a housekeeping gene from the B. burgdorferi sensu stricto strain into a homologous locus of another bird-associated strain. Our results support the hypothesis that recombination maintains a majority of sequence polymorphism within Borrelia populations because of the re-assortment of pre-existing sequence variants. Even if our findings of broad genetic diversity among 8 strains cultured from ticks that fed on a single bird could be the exception rather than the rule, they support the theory that the diversity and evolution of LB spirochetes is driven mainly by the host.


Asunto(s)
Aves/microbiología , Borrelia burgdorferi/clasificación , Borrelia burgdorferi/genética , Garrapatas/microbiología , Animales , Borrelia burgdorferi/aislamiento & purificación , Genes Esenciales , Variación Genética , Datos de Secuencia Molecular , Filogenia
8.
Appl Environ Microbiol ; 79(5): 1444-53, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23263953

RESUMEN

Comparative analysis of ospC genes from 127 Borrelia burgdorferi sensu stricto strains collected in European and North American regions where Lyme disease is endemic and where it is not endemic revealed a close relatedness of geographically distinct populations. ospC alleles A, B, and L were detected on both continents in vectors and hosts, including humans. Six ospC alleles, A, B, L, Q, R, and V, were prevalent in Europe; 4 of them were detected in samples of human origin. Ten ospC alleles, A, B, D, E3, F, G, H, H3, I3, and M, were identified in the far-western United States. Four ospC alleles, B, G, H, and L, were abundant in the southeastern United States. Here we present the first expanded analysis of ospC alleles of B. burgdorferi strains from the southeastern United States with respect to their relatedness to strains from other North American and European localities. We demonstrate that ospC genotypes commonly associated with human Lyme disease in European and North American regions where the disease is endemic were detected in B. burgdorferi strains isolated from the non-human-biting tick Ixodes affinis and rodent hosts in the southeastern United States. We discovered that some ospC alleles previously known only from Europe are widely distributed in the southeastern United States, a finding that confirms the hypothesis of transoceanic migration of Borrelia species.


Asunto(s)
Alelos , Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Borrelia burgdorferi/genética , Ixodes/microbiología , Roedores/microbiología , Animales , Borrelia burgdorferi/aislamiento & purificación , ADN Bacteriano/química , ADN Bacteriano/genética , Europa (Continente) , Variación Genética , Genotipo , Humanos , Datos de Secuencia Molecular , América del Norte , Análisis de Secuencia de ADN
10.
Ticks Tick Borne Dis ; 2(3): 123-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21890064

RESUMEN

Borrelia burgdorferi sensu lato (s.l.) complex is a diverse group of worldwide distributed bacteria that includes 18 named spirochete species and a still not named group proposed as genomospecies 2. Descriptions of new species and variants continue to be recognized, so the current number of described species is probably not final. Most of known spirochete species are considered to have a limited distribution. Eleven species from the B. burgdorferi s.l. complex were identified in and strictly associated with Eurasia (B. afzelii, B. bavariensis, B. garinii, B. japonica, B. lusitaniae, B. sinica, B. spielmanii, B. tanukii, B. turdi, B. valaisiana, and B. yangtze), while another 5 (B. americana, B. andersonii, B. californiensis, B. carolinensis, and B. kurtenbachii) were previously believed to be restricted to the USA only. B. burgdorferi sensu stricto (s.s.), B. bissettii, and B. carolinensis share the distinction of being present in both the Old and the New World. Out of the 18 genospecies, 3 commonly and 4 occasionally infect humans, causing Lyme borreliosis (LB) - a multisystem disease that is often referred to as the 'great imitator' due to diversity of its clinical manifestations. Among the genospecies that commonly infect people, i.e. B. burgdorferi s.s., B. afzelii, and B. garinii, only B. burgdorferi s.s. causes LB both in the USA and in Europe, with a wide spectrum of clinical conditions ranging from minor cutaneous erythema migrans (EM) to severe arthritis or neurological manifestations. The epidemiological data from many European countries and the USA show a dramatic increase of the diagnosed cases of LB due to the development of new progressive diagnostic methods during the last decades (Hubálek, 2009). Recently, the definition of the disease has also changed. What was not considered Lyme borreliosis before might be now.


Asunto(s)
Vectores Arácnidos/microbiología , Técnicas de Tipificación Bacteriana/métodos , Borrelia burgdorferi/aislamiento & purificación , Enfermedad de Lyme , Garrapatas/microbiología , Animales , Vectores Arácnidos/fisiología , Asia , Aves , Borrelia burgdorferi/clasificación , Borrelia burgdorferi/genética , Borrelia burgdorferi/patogenicidad , ADN Bacteriano/genética , Reservorios de Enfermedades , Europa (Continente) , Variación Genética , Humanos , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/epidemiología , Enfermedad de Lyme/microbiología , Enfermedad de Lyme/transmisión , Filogenia , Filogeografía , Reacción en Cadena de la Polimerasa , Salud Pública , Roedores , Especificidad de la Especie , Garrapatas/fisiología , Estados Unidos
11.
Opt Express ; 19(9): 8539-45, 2011 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-21643104

RESUMEN

Recently proposed binary defocusing techniques have led to ultrafast speed 3D shape measurement, but they are generally limited to measurement of a single object at a time. Introducing additional gray coded patterns for point-by-point phase unwrapping could permit simultaneous multiple-object measurement. However, when the objects are moving rapidly, the displacement between the first captured pattern and the last can be significant, and pose challenges related to the precisely designed gray codes. This paper presents a new phase unwrapping strategy that combines the conventional spatial phase unwrapping with the gray code to resolve motion related phase unwrapping problems. A system with a speed of 5,000 Hz was developed to verify the performance of the proposed technique.


Asunto(s)
Algoritmos , Inteligencia Artificial , Imagenología Tridimensional/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Grabación en Video/métodos , Movimiento (Física)
12.
Int J Syst Evol Microbiol ; 61(Pt 2): 381-383, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20305062

RESUMEN

A group of 16 isolates with genotypic characteristics different from those of known species of the Borrelia burgdorferi sensu lato complex were cultured from ear biopsies of the rodents Peromyscus gossypinus and Neotoma floridana trapped at five localities in South Carolina, USA, and from the tick Ixodes minor feeding on N. floridana. Multilocus sequence analysis of members of the novel species, involving the 16S rRNA gene, the 5S-23S (rrf-rrl) intergenic spacer region and the flagellin, ospA and p66 genes, was conducted and published previously and was used to clarify the taxonomic status of the novel group of B. burgdorferi sensu lato isolates. Phylogenetic analysis based on concatenated sequences of the five analysed genomic loci showed that the 16 isolates clustered together but separately from other species in the B. burgdorferi sensu lato complex. The analysed group therefore represents a novel species, formally described here as Borrelia carolinensis sp. nov., with the type strain SCW-22(T) (=ATCC BAA-1773(T) =DSM 22119(T)).


Asunto(s)
Grupo Borrelia Burgdorferi/clasificación , Ixodes/microbiología , Filogenia , Sigmodontinae/microbiología , Animales , Técnicas de Tipificación Bacteriana , Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/aislamiento & purificación , ADN Bacteriano/genética , ADN Espaciador Ribosómico/genética , Flagelina/genética , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , South Carolina
13.
J Clin Microbiol ; 47(12): 3875-80, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19846628

RESUMEN

Analysis of borrelia isolates collected from ticks, birds, and rodents from the southeastern United States revealed the presence of well-established populations of Borrelia burgdorferi sensu stricto, Borrelia bissettii, Borrelia carolinensis, and Borrelia sp. nov. Multilocus sequence analysis of five genomic loci from seven samples representing Borrelia sp. nov. isolated from nymphal Ixodes minor collected in South Carolina showed their close relatedness to California strains known as genomospecies 1 and separation from any other known species of the B. burgdorferi sensu lato complex. One nucleotide difference in the size of the 5S-23S intergenic spacer region, one substitution in 16S rRNA gene signature nucleotides, and silent nucleotide substitutions in sequences of the gene encoding flagellin and the gene p66 clearly separate Borrelia sp. nov. isolates from South Carolina into two subgroups. The sequences of isolates of each subgroup share the same restriction fragment length polymorphism patterns of the 5S-23S intergenic spacer region and contain unique signature nucleotides in the 16S rRNA gene. We propose that seven Borrelia sp. nov. isolates from South Carolina and two California isolates designated as genomospecies 1 comprise a single species, which we name Borrelia americana sp. nov. The currently recognized geographic distribution of B. americana is South Carolina and California. All strains are associated with Ixodes pacificus or Ixodes minor and their rodent and bird hosts.


Asunto(s)
Grupo Borrelia Burgdorferi/clasificación , Grupo Borrelia Burgdorferi/genética , Enfermedad de Lyme/microbiología , Animales , Antígenos de Superficie/genética , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Vacunas Bacterianas/genética , California , ADN Espaciador Ribosómico/análisis , ADN Espaciador Ribosómico/genética , Flagelina/genética , Genes de ARNr , Ixodes/clasificación , Ixodes/microbiología , Lipoproteínas/genética , Datos de Secuencia Molecular , Filogenia , Porinas/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , South Carolina , Especificidad de la Especie
14.
J Comb Chem ; 11(3): 385-92, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19298082

RESUMEN

The role of various techniques for visualization of high-dimensional data is demonstrated in the context of combinatorial high-throughput experimentation (HTE). Applying visualization tools, we identify which constituents of catalysts are associated with final products in a huge combinatorially generated data set of heterogeneous catalysts, and catalytic activity regions are identified with respect to pentanary composition spreads of catalysts. A radial visualization scheme directly visualizes pentanary composition spreads in two-dimensional (2D) space and catalytic activity of a final product by combining high-throughput results from five slate libraries. A glyph plot provides many possibilities for visualizing high-dimensional data with interactive tools. For catalyst discovery and lead optimization, this work demonstrates how large multidimensional catalysis data sets are visualized in terms of quantitative composition activity relationships (QCAR) to effectively identify the relevant key role of compositions (i.e., lead compositions) of catalysts.


Asunto(s)
Técnicas Químicas Combinatorias/métodos , Relación Estructura-Actividad Cuantitativa , Catálisis , Simulación por Computador , Procesamiento de Imagen Asistido por Computador , Modelos Químicos , Bibliotecas de Moléculas Pequeñas/química
15.
J Clin Microbiol ; 47(1): 134-41, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19020062

RESUMEN

Approximately 118 Borrelia isolates were cultured from a variety of rodents, birds, and ticks collected in the southern United States. In addition to a highly diverse group of Borrelia bissettii strains and a homogenous group of Borrelia burgdorferi sensu stricto strains, a group of 16 isolates with unusual characteristics was found. The isolates were cultured from ear biopsy samples of the rodents Peromyscus gossypinus and Neotoma floridana trapped at five localities in South Carolina. A multilocus sequence analysis of the rrf-rrl intergenic spacer, 16S rRNA, fla, ospA, and p66 genes were used to clarify the taxonomic status of the new group of B. burgdorferi sensu lato isolates. Thirteen species of the B. burgdorferi sensu lato complex were used as controls. Unique restriction fragment length polymorphism patterns of the rrf-rrl intergenic spacer region and fla gene were recognized. Unique signature nucleotides were also found in the 16S rRNA gene. A phylogenetic analysis shows that the 16 new isolates cluster together but separately from the other species in the B. burgdorferi sensu lato complex. Our data strongly support the recognition of the 16 isolates as a new B. burgdorferi sensu lato species. We propose to name this genospecies "Borrelia carolinensis" with respect to the place of its currently known geographic location.


Asunto(s)
Grupo Borrelia Burgdorferi/clasificación , Grupo Borrelia Burgdorferi/aislamiento & purificación , Peromyscus/microbiología , Sigmodontinae/microbiología , Animales , Proteínas Bacterianas/genética , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Genes de ARNr , Datos de Secuencia Molecular , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Sudeste de Estados Unidos
16.
J Parasitol ; 94(6): 1351-6, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18576863

RESUMEN

Thirty-five strains of the Lyme disease spirochete Borrelia burgdorferi sensu lato (B. burgdorferi s. l.) were isolated from the blacklegged tick vector Ixodes scapularis in South Carolina, Georgia, Florida, and Rhode Island. They were characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of rrf (5S)-rrl (23S) intergenic spacer amplicons. PCR-RFLP analysis indicated that the strains represented at least 3 genospecies (including a possible novel genospecies) and 4 different restriction patterns. Thirty strains belonged to the genospecies B. burgdorferi sensu stricto (B. burgdorferi s. s.), 4 southern strains were identified as B. bissettii, and strain SCCH-5 from South Carolina exhibited MseI and DraI restriction patterns different from those of previously reported genospecies. Complete sequences of rrf-rrl intergenic spacers from 14 southeastern and northeastern strains were determined and the phylogenetic relationships of these strains were compared. The 14 strains clustered into 3 separate lineages on the basis of sequence analysis. These results were confirmed by phylogenetic analysis based on 16S rDNA sequence analysis.


Asunto(s)
Vectores Arácnidos/microbiología , Grupo Borrelia Burgdorferi/genética , Ixodes/microbiología , Animales , Secuencia de Bases , Grupo Borrelia Burgdorferi/clasificación , Grupo Borrelia Burgdorferi/aislamiento & purificación , ADN Ribosómico/química , ADN Espaciador Ribosómico/química , Femenino , Masculino , Datos de Secuencia Molecular , New England , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico 16S/genética , Mapeo Restrictivo , Sudeste de Estados Unidos
17.
Infect Immun ; 75(7): 3633-40, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17485458

RESUMEN

Antimicrobial peptides are major components of host innate immunity, a well-conserved, evolutionarily ancient defensive mechanism. Infectious disease-bearing vector ticks are thought to possess specific defense molecules against the transmitted pathogens that have been acquired during their evolution. We found in the tick Haemaphysalis longicornis a novel parasiticidal peptide named longicin that may have evolved from a common ancestral peptide resembling spider and scorpion toxins. H. longicornis is the primary vector for Babesia sp. parasites in Japan. Longicin also displayed bactericidal and fungicidal properties that resemble those of defensin homologues from invertebrates and vertebrates. Longicin showed a remarkable ability to inhibit the proliferation of merozoites, an erythrocyte blood stage of equine Babesia equi, by killing the parasites. Longicin was localized at the surface of the Babesia sp. parasites, as demonstrated by confocal microscopic analysis. In an in vivo experiment, longicin induced significant reduction of parasitemia in animals infected with the zoonotic and murine B. microti. Moreover, RNA interference data demonstrated that endogenous longicin is able to directly kill the canine B. gibsoni, thus indicating that it may play a role in regulating the vectorial capacity in the vector tick H. longicornis. Theoretically, longicin may serve as a model for the development of chemotherapeutic compounds against tick-borne disease organisms.


Asunto(s)
4-Butirolactona/análogos & derivados , Vectores Artrópodos/química , Babesia/efectos de los fármacos , Defensinas , Garrapatas/química , 4-Butirolactona/administración & dosificación , 4-Butirolactona/química , 4-Butirolactona/genética , 4-Butirolactona/metabolismo , Secuencia de Aminoácidos , Animales , Vectores Artrópodos/inmunología , Vectores Artrópodos/metabolismo , Babesia/clasificación , Babesia/crecimiento & desarrollo , Babesia/patogenicidad , Babesiosis/parasitología , Babesiosis/veterinaria , Secuencia de Bases , Defensinas/administración & dosificación , Defensinas/química , Defensinas/genética , Defensinas/metabolismo , Enfermedades de los Perros/parasitología , Perros , Femenino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Garrapatas/inmunología , Garrapatas/metabolismo
18.
Int J Syst Evol Microbiol ; 55(Pt 2): 685-693, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15774644

RESUMEN

TXW-1, a Borrelia strain isolated in March 1998 from an adult male Dermacentor variabilis tick feeding on a coyote from Webb county, Texas, USA, was characterized by using randomly amplified polymorphic DNA (RAPD) analysis, RFLP and sequence analysis of flaB and rrs (16S rRNA gene), DNA-DNA hybridization analysis, SDS-PAGE and Western blotting with mAbs. It shows different banding patterns in RFLP analysis of flaB and forms distinct branches in phylogenetic analysis derived from flaB and rrs genes. It differs from other borreliae based on the banding patterns obtained by RAPD analysis. This strain contains a small, 38-kDa endoflagellar protein. DNA-DNA hybridization experiments revealed that the levels of DNA reassociation between TXW-1 and previously described relapsing fever borreliae were 38.64 % (Borrelia turicatae), 38.40 % (Borrelia parkeri), 7.39 % (Borrelia hermsii) and 18.30 % (Borrelia coriaceae). However, the level of DNA relatedness between B. parkeri and B. turicatae was 78.78 %. Sequence analyses of flaB and rrs genes indicate that the similarities of nucleotide sequences among TXW-1 and B. turicatae or B. parkeri are less than that between B. turicatae and B. parkeri, and that the genetic distances among TXW-1 and B. turicatae or B. parkeri are greater than that between B. turicatae and B. parkeri. TXW-1 lacks an ospC gene. Electron microscope observations showed that this spirochaete had different morphological structures compared to previously described relapsing fever borreliae. All the results obtained from the above-mentioned analyses indicate that TXW-1 is different from other described Borrelia species and that it represents a novel species of Borrelia. We have been unable to revive frozen cultures and so can not meet the requirements of the Bacteriological Code to deposit viable type material at two different culture collections. Therefore we use the Candidatus designation; based on these results, the species 'Candidatus Borrelia texasensis' is proposed.


Asunto(s)
Borrelia/clasificación , Dermacentor/microbiología , Animales , Borrelia/química , Borrelia/genética , Borrelia/aislamiento & purificación , Coyotes/parasitología , ADN Bacteriano/análisis , Dermacentor/fisiología , Perros/parasitología , Flagelina/genética , Genes de ARNr , Masculino , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fenotipo , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico 16S/genética , Técnica del ADN Polimorfo Amplificado Aleatorio , Fiebre Recurrente/microbiología , Análisis de Secuencia de ADN , Texas
19.
Folia Parasitol (Praha) ; 52(4): 279-94, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16405291

RESUMEN

Lyme borreliosis (LB) is a serious infectious disease of humans and some domestic animals in temperate regions of the Northern Hemisphere. It is caused by certain spirochetes in the Borrelia burgdorferi sensu lato (s.l.) species complex. The complex consists of 11 species (genospecies). Borrelia burgdorferi sensu stricto (s.s.), Borrelia garinii and Borrelia afzelii are the major agents of human disease. Borrelia burgdorferi s.l. species are transmitted mainly by ticks belonging to the Ixodes ricinus species complex plus a few additional species not currently assigned to the complex. B. burgdorferi infections may produce an acute or chronic disease with a wide array of clinical symptoms such as erythema migrans (EM), carditis, arthritis, neuroborreliosis, and acrodermatitis chronica atrophicans (ACA). Differences in LB spirochetes 'genospecies' and strains/isolates determine the occurrence and severity of this multi-system disease. Accurate and reliable identification of the LB spirochetes in ticks as well as knowledge of their prevalence are essential for prevention against the disease and development of an effective vaccine. An overview of the knowledge of molecular factors with emphasis on potential protein-carbohydrate interactions in the tick-borrelia system is the main focus of this review.


Asunto(s)
Vectores Arácnidos/microbiología , Grupo Borrelia Burgdorferi , Ixodes/microbiología , Enfermedad de Lyme/microbiología , Animales , Antígenos Bacterianos/inmunología , Vectores Arácnidos/citología , Vectores Arácnidos/inmunología , Grupo Borrelia Burgdorferi/clasificación , Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/inmunología , Grupo Borrelia Burgdorferi/patogenicidad , Glicoconjugados/fisiología , Hemocitos/citología , Hemocitos/parasitología , Interacciones Huésped-Parásitos , Humanos , Ixodes/citología , Ixodes/inmunología , Lectinas/fisiología , Enfermedad de Lyme/inmunología
20.
J Parasitol ; 90(3): 485-9, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15270090

RESUMEN

Gray squirrels, Sciurus carolinensis, were livetrapped in 2 different habitat types, woodland (67 squirrels) and parkland (53 squirrels), in southeastern Georgia. Ectoparasites were recovered from anesthetized squirrels and compared between hosts from the 2 habitats. Because of the absence of low vegetation in parkland habitats, it was hypothesized that the ectoparasite fauna, especially ticks and chiggers, would be more diverse on woodland squirrels. The results were generally in agreement with this hypothesis. Seventeen species of ectoparasites were recovered from woodland squirrels, compared with 6 species from parkland squirrels. Five species of ticks and 3 species of chiggers parasitized the woodland squirrels compared with no ticks or chiggers on the parkland squirrels. Significantly higher infestation prevalences were recorded on woodland compared with parkland squirrels for the flea Orchopeas howardi, the tick Amblyomma americanum, and the mesostigmatid mite Androlaelaps fahrenholzi. The mean intensity for O. howardi also was significantly higher on woodland than on parkland squirrels. Because a new strain of Bartonella sp. was isolated recently from S. carolinensis in Georgia, selected ectoparasites from this study were screened for bartonellae by polymerase chain reaction (PCR). Some of the fleas and lice, but none of the mites tested, were PCR positive, suggesting that fleas, or lice, or both, might be vectors of bartonellae between squirrels. Six distinct strains of Bartonella sp. were detected, 2 in fleas and 4 in lice.


Asunto(s)
Vectores Artrópodos/microbiología , Bartonellaceae/aislamiento & purificación , Infestaciones Ectoparasitarias/veterinaria , Enfermedades de los Roedores/parasitología , Sciuridae/parasitología , Animales , Anoplura/genética , Anoplura/microbiología , Vectores Artrópodos/genética , Bartonellaceae/genética , Infecciones por Bartonellaceae/transmisión , Infecciones por Bartonellaceae/veterinaria , ADN/química , Infestaciones Ectoparasitarias/epidemiología , Infestaciones Ectoparasitarias/parasitología , Ambiente , Georgia/epidemiología , Ácaros/genética , Ácaros/microbiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Enfermedades de los Roedores/epidemiología , Siphonaptera/genética , Siphonaptera/microbiología , Garrapatas/genética , Garrapatas/microbiología , Trombiculidae/genética , Trombiculidae/microbiología
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