PMID(sorted ascending)
ehrlichia chaffeensis infection of sika deer, determine whether ehrlichia chaffeensis exists in japan, we used pcr to examine blood from sika deer in nara, japan. of 117 deer, 36 (31%) were infected with e. chaffeensis. the e. chaffeensis 16s rrna base and groel amino acid sequences from japan were most closely related to those of e. chaffeensis arkansas.200919961683
niche partitioning of borrelia burgdorferi and borrelia miyamotoi in the same tick vector and mammalian reservoir species.the lyme borreliosis agent borrelia burgdorferi and the relapsing fever group species borrelia miyamotoi co-occur in the united states. we used species-specific, quantitative polymerase chain reaction to study both species in the blood and skin of peromyscus leucopus mice and host-seeking ixodes scapularis nymphs at a connecticut site. bacteremias with b. burgdorferi or b. miyamotoi were most prevalent during periods of greatest activity for nymphs or larvae, respectively. whereas b. burgdorferi ...200919996447
elemol and amyris oil repel the ticks ixodes scapularis and amblyomma americanum (acari: ixodidae) in laboratory bioassays.the essential oil from amyris balsamifera (rutaceae) and elemol, a principal constituent of the essential oil of osage orange, maclura pomifera (moraceae) were evaluated in in vitro and in vivo laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, ixodes scapularis, and the lone star tick, amblyomma americanum. both bioassays took advantage of the tendency of these host-seeking ticks to climb slender vertical surfaces. in one bioassay, the central porti ...201020016930
identification of protective antigens by rna interference for control of the lone star tick, amblyomma americanum.the lone star tick, amblyomma americanum, vectors pathogens of emerging diseases of humans and animals in the united states. currently, measures are not available for effective control of a. americanum infestations. development of vaccines directed against tick proteins may reduce tick infestations and the transmission of tick-borne pathogens. however, the limiting step in tick vaccine development has been the identification of tick protective antigens. herein, we report the application of rna i ...201020018267
larval keys to the genera of ixodidae (acari) and species of ixodes (latreille) ticks established in california, hard (ixodidae) ticks transmit at least 8 zoonotic disease agents (1 virus, 6 bacteria, 1 protozoan) to humans or other animals. the correct taxonomic identification of all 3 parasitic stages (larvae, nymphs, adults) of ticks is integral to understanding host-tick associations and disease dynamics, but immature ticks, especially the larvae, can be difficult to identify. here, we present larval keys to the 4 genera of ixodidae (dermacentorkoch, 1844; haemaphysaliskoch, 1844; ixodes ...200820027236
molecular and clinical evidence of ehrlichia chaffeensis infection in cameroonian patients with undifferentiated febrile the u.s.a., human monocytotropic ehrlichiosis (hme) caused by ehrlichia chaffeensis is an emerging tick-transmitted zoonosis. in cameroon, where e. canis, e. chaffeensis and e. ewingii have recently been detected in dogs and/or ticks (rhipicephalus sanguineus), the potential exists for human infections. patients from the coastal region of cameroon who had acute fevers of unknown aetiology were therefore checked for ehrlichial infection, using a real-time pcr that amplifies part of a genus-spe ...200920030996
platelet aggregation inhibitors from hematophagous animals.salivary glands from blood-sucking animals (e.g., mosquitoes, bugs, sand flies, fleas, ticks, leeches, hookworms, bats) are a rich source of bioactive molecules that counteract hemostasis in a redundant and synergistic manner. this review discusses recent progress in the identification of salivary inhibitors of platelet aggregation, their molecular characterization, and detailed mechanism of action. diversity of inhibitors is remarkable, with distinct families of proteins characterized as apyras ...200920035779
rhipicephalus (boophilus) microplus: clotting time in tick-infested skin varies according to local inflammation and gene expression patterns in tick salivary glands.ticks deposit saliva at the site of their attachment to a host in order to inhibit haemostasis, inflammation and innate and adaptive immune responses. the anti-haemostatic properties of tick saliva have been described by many studies, but few show that tick infestations or its anti-haemostatic components exert systemic effects in vivo. in the present study, we extended these observations and show that, compared with normal skin, bovine hosts that are genetically susceptible to tick infestations ...201020045690
severe ehrlichia infection in pediatric oncology and stem cell transplant patients.ehrlichiosis, a tickborne illness transmitted by tick vectors amblyomma americanum and ixodes scapularis, can be acquired in endemic areas. clinical manifestations range from asymptomatic to fulminant in nature. we report three cases of ehrlichiosis in pediatric oncology patients, one of whom was a stem cell transplant recipient. early symptoms included fever, malaise, and vague gastrointestinal symptoms. laboratory abnormalities were initially attributed to chemotherapy toxicity. illness was se ...201020052776
ability of two natural products, nootkatone and carvacrol, to suppress ixodes scapularis and amblyomma americanum (acari: ixodidae) in a lyme disease endemic area of new jersey.we evaluated the ability of the natural, plant-derived acaricides nootkatone and carvacrol to suppress ixodes scapularis say and amblyomma americanum (l.) (acari: ixodidae). aqueous formulations of 1 and 5% nootkatone applied by backpack sprayer to the forest litter layer completely suppressed i. scapularis nymphs through 2 d. thereafter, the level of reduction gradually declined to < or =50% at 28 d postapplication. against a. americanum nymphs, 1% nootkatone was less effective, but at a 5% con ...200920069863
[ehrlichiosis/anaplasmosis].ehrlichiosis and anaplasmosis are zoonoses caused by bacteria from the family anaplasmataceae, including human and animal pathogens. the human pathogens are ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (hme), anaplasma phagocytophilum, the pathogen causing human granulocytic anaplasmosis (hga), e. ewingii and neorickettsia sennetsu, granulocytotropic and monocytotropic ehrlichia species, respectively. ehrlichia spp. are small, gram-negative, obligate intracellular b ...200920077398
wide dispersal and possible multiple origins of low-copy-number plasmids in rickettsia species associated with blood-feeding arthropods.plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. we report the existence of plasmids in rickettsia (rickettsiales; rickettsiaceae) species, including rickettsia akari, "candidatus rickettsia amblyommii," r. bellii, r. rhipicephali, and reis, the rickettsial endosymbiont of ixodes scapularis. all of the rickettsiae were isolated from humans or north and south american ticks. r. parkeri isolates from b ...201020097813
endemic tickborne infectious diseases in louisiana and the gulf south.most emerging infectious diseases today, such as west nile virus and sudden acute respiratory distress syndrome (sars), arise from zoonotic reservoirs and many are transmitted by arthropod vectors. ticks are among the most competent and versatile arthropod vectors of infectious diseases because ticks of all ages and both sexes remain infectious for generations without having to reacquire infections from reservoir hosts. today, ticks transmit the most common arthropod-borne infectious disease in ...200920108827
extraction of total nucleic acids from ticks for the detection of bacterial and viral pathogens.ticks harbor numerous bacterial, protozoal, and viral pathogens that can cause serious infections in humans and domestic animals. active surveillance of the tick vector can provide insight into the frequency and distribution of important pathogens in the environment. nucleic-acid based detection of tick-borne bacterial, protozoan, and viral pathogens requires the extraction of both dna and rna (total nucleic acids) from ticks. traditional methods for nucleic acid extraction are limited to extrac ...201020180313
detection of a new arsenophonus-type bacterium in canadian populations of the rocky mountain wood tick, dermacentor andersoni.ticks of the genus dermacentor are important vectors of human and animal pathogens in north america. they also carry a variety of endosymbiotic (i.e. non-pathogenic) bacteria. the american dog tick, d. variabilis, is known to be infected with gammaproteobacteria of the genus arsenophonus. however, there have been no previous reports of arsenophonus-type bacteria in the rocky mountain wood tick, d. andersoni, a species that is sympatric with d. variabilis in the western parts of its distributiona ...201020186465
a 60-year meta-analysis of tick paralysis in the united states: a predictable, preventable, and often misdiagnosed poisoning.tick paralysis (tp) is a neurotoxic poisoning primarily afflicting young girls in endemic regions. recent case series of tp have described increasing misdiagnoses of tp as the guillain-barré syndrome (gbs). a meta-analysis of the scientific literature was conducted using internet search engines to assess the evolving epidemiology of tp. fifty well-documented cases of tp were analyzed over the period 1946-2006. cases were stratified by demographics, clinical manifestations, and outcomes. misdiagn ...201020186584
bartonella spp. transmission by ticks not established.bartonella spp. infect humans and many animal species. mainly because pcr studies have demonstrated bartonella dna in ticks, some healthcare providers believe that these microorganisms are transmitted by ticks. b. henselae, in particular, is regarded as being present in and transmissible by the ixodes scapularis tick. the presence of a microbial agent within a tick, however, does not imply that the tick might transmit it during the course of blood feeding and does not confer epidemiologic import ...201020202410
potential for tick-borne worldwide vectors of human infectious diseases, ticks are considered to be second only to mosquitoes. each tick species has preferred environmental conditions and biotopes that determine its geographic distribution, the pathogens it vectors, and the areas that pose risk for tick-borne diseases. researchers have identified an increasing number of bacterial pathogens that are transmitted by ticks, including anaplasma, borrelia, ehrlichia, and rickettsia spp. recent reports involving humans and ...201020202411
blood meal analysis to identify reservoir hosts for amblyomma americanum ticks.efforts to identify wildlife reservoirs for tick-borne pathogens are frequently limited by poor understanding of tick-host interactions and potentially transient infectivity of hosts under natural conditions. to identify reservoir hosts for lone star tick (amblyomma americanum)-associated pathogens, we used a novel technology. in field-collected ticks, we used pcr to amplify a portion of the 18s rrna gene in remnant blood meal dna. reverse line blot hybridization with host-specific probes was th ...201020202418
borrelia, ehrlichia, and rickettsia spp. in ticks removed from persons, texas, regarding the type, frequency, and distribution of tick-borne pathogens and bacterial agents are not widely available for many tick species that parasitize persons in the southern united states. we therefore analyzed the frequency and identity of pathogens and bacterial agents in ticks removed from humans and subsequently submitted to the texas department of state health services, zoonosis control program, from october 1, 2004, through september 30, 2008. the data showed associations of bac ...201020202419
meeting the challenges of on-host and off-host water balance in blood-feeding this review, we describe water balance requirements of blood-feeding arthropods, particularly contrasting dehydration tolerance during the unfed, off-host state and the challenges of excess water that accompany receipt of the bloodmeal. most basic water balance characteristics during the off-host stage are applicable to other terrestrial arthropods, as well. a well-coordinated suite of responses enable arthropods to conserve water resources, enhance their desiccation tolerance, and increase t ...201020206630
silencing of three amblyomma americanum (l.) insulin-like growth factor binding protein-related proteins prevents ticks from feeding to repletion.the insulin-like growth factor (igf) binding proteins (igfbp) family is the regulatory arm of the igf signaling system that control mitogenic and anabolic actions of igf peptide hormones. this study describes cloning and biological characterization of three amblyomma americanum (l.) (aam) proteins that show amino-terminal sequence and secondary structure similarity to the igfbp superfamily. the three molecules here provisionally identified as aamigfbp-rp1 and short (s) and long (l) aamigfbp-rp6 ...201020228352
insecticides to control the european corn borer in field corn. 194720264508
infestation of a raccoon by amblyomma americanum. 194720264533
rite of amblyomma americanum associated with possible tick paralysis. 194720340890
population genetics of amblyomma americanum (acari: ixodidae) collected from arkansas.lone star ticks, amblyomma americanum l. (acari: ixodidae),infest multiple hosts such as birds, and mammals of various sizes (rodents to white-tailed deer) and can harbor human pathogens such as borrelia lonestari and ehrlichiosis chaffeensis. the population structure of 251 a. americanum ticks, collected from canines and two white-tailed deer in six arkansas ecoregions, was examined using dna sequences of a 247-bp region of the mitochondrial dna ribosomal rna 16s gene. of the 247 nucleotide cha ...201020380295
bacterial diversity in amblyomma americanum (acari: ixodidae) with a focus on members of the genus rickettsia.the lone star tick, amblyomma americanum (acari: ixodidae), is commonly reported from people and animals throughout the eastern u.s. and is associated with transmission of a number of emerging diseases. to better define the microbial communities within lone star ticks, 16s rrna gene based analysis using bacteria-wide primers, followed by sequencing of individual clones (n = 449) was used to identify the most common bacterial operational taxonomic units (otus) present within colony-reared and wil ...201020380308
disrupting the amblyomma americanum (l.) cd147 receptor homolog prevents ticks from feeding to repletion and blocks spontaneous detachment of ticks from their host.the cd147 receptor is a cell-surface glycoprotein in the igg family that plays pivotal roles in intercellular interactions involved with numerous physiological and pathological processes such as extracellular matrix remodeling. we previously found an amblyomma americanum (aam) tick cd147 receptor homolog among genes that were up regulated in response to tick feeding stimuli. this study characterizes an aamcd147 receptor protein that is 72-83% conserved in other tick species and possess character ...201020451606
bacterial pathogens in ixodid ticks from a piedmont county in north carolina: prevalence of rickettsial north carolina, reported human cases of tick-borne illness, specifically rocky mountain spotted fever, have escalated over the past decade. to determine the relative abundance of vectors and to estimate the risk of acquiring a tick-borne illness in peri-residential landscapes, ticks were collected in chatham county, a typical piedmont county and, samples of the ticks were tested for infection with selected bacterial pathogens using real-time quantitative polymerase chain reaction assays. tick ...201020455778
host associations of dermacentor, amblyomma, and ixodes (acari: ixodidae) ticks in tennessee.from april 2007 to september 2008, 1,793 adult and nymphal ixodid ticks were collected from 49 counties in tennessee. six species were identified, including dermacentor variabilis (say), amblyomma americanum (l.), ixodes texanus (banks), ixodes cookei packard, ixodes scapularis (say), and amblyomma maculatum koch, from 13 medium- to large-sized mammalian hosts and dragging through vegetation. raccoons were the most common vertebrate source (198 captures), accounting for 60% of ticks collected. d ...201020496589
sdetection of vector-borne agents in lone star ticks, amblyomma americanum (acari: ixodidae), from this study, we evaluated amblyomma americanum (lone star tick) in mississippi for the presence of ehrlichia chaffeensis, causative agent of human monocytic ehrlichiosis; ehrlichia ewingii, causative agent of human and canine granulocytic ehrlichiosis; borrelia lonestari, putative agent of southern tick-associated rash illness; francisella tularensis, the agent of tularemia; and rickettsia spp., particularly r. amblyommii, a suspected pathogen. we collected adult a. americanum from four region ...201020496596
potential of medicinal plants in mosquito control.medicinal plants have long history as important components in traditional medicine, and food of humans since ancient egyptians and chinese. naturally occurring botanical compounds contain a broad range of chemical active ingredients can intervene in all biological processes of the mosquito, thus interrupt its life cycle and dispersal and reduce harms to humans and animals. many medicinal plants were tested for their pesticide and repellent potential, as crude material, essential oils or individu ...201020503582
human ehrlichiosis and anaplasmosis.human ehrlichiosis and anaplasmosis are acute febrile tick-borne diseases caused by various members of the genera ehrlichia and anaplasma (anaplasmataceae). human monocytotropic ehrlichiosis has become one of the most prevalent life-threatening tick-borne disease in the united states. ehrlichiosis and anaplasmosis are becoming more frequently diagnosed as the cause of human infections, as animal reservoirs and tick vectors have increased in number and humans have inhabited areas where reservoir ...201020513551
ehrlichia ewingii infection and exposure rates in dogs from the southcentral united states.we used pcr and a novel serologic assay to determine infection and exposure rates to ehrlichia ewingii in dogs from an area of northeast oklahoma and northwest arkansas where amblyomma americanum ticks are abundant. of 143 dogs assayed, 13 (9.1%) harbored e. ewingii by pcr and 64 (44.8%) had antibodies to e. ewingii detected using a peptide-based microtiter plate elisa. dogs were more likely (p=0.001) to be positive by pcr if sampled in august (30.8%) but no association was found between seropos ...201020541322
crystal structure and functional characterization of an immunomodulatory salivary cystatin from the soft tick ornithodoros moubata.the saliva of blood-feeding parasites is a rich source of peptidase inhibitors that help to overcome the host's defence during host-parasite interactions. using proteomic analysis, the cystatin omc2 was demonstrated in the saliva of the soft tick ornithodoros moubata, an important disease vector transmitting african swine fever virus and the spirochaete borrelia duttoni. a structural, biochemical and biological characterization of this peptidase inhibitor was undertaken in the present study. rec ...201020545626
pharmacology of signaling induced by dopamine d(1)-like receptor activation.dopamine d(1)-like receptors consisting of d(1) and d(5) subtypes are intimately implicated in dopaminergic regulation of fundamental neurophysiologic processes such as mood, motivation, cognitive function, and motor activity. upon stimulation, d(1)-like receptors initiate signal transduction cascades that are mediated through adenylyl cyclase or phosphoinositide metabolism, with subsequent enhancement of multiple downstream kinase cascades. the latter actions propagate and further amplify the r ...201020547182
quantum of infection of francisella tularensis tularensis in host-seeking dermacentor variabilis.the american dog tick, dermacentor variabilis, is fundamental to the perpetuation of francisella tularensis tularensis on martha's vineyard, massachusetts, u.s.a. although infected ticks are relatively common on the island, human cases deriving from tick bite are rare. it may be that the quantum of bacteria within these naturally infected ticks is frequently too small to cause disease. accordingly, we quantified the amount of f.t. tularensis bacteria in host-seeking ticks from the island. contra ...201020563231
correlations between bacterial ecology and mobile dna.several factors can affect the density of mobile dna in bacterial genomes including rates of exposure to novel gene pools, recombination, and reductive evolution. these traits are difficult to measure across a broad range of bacterial species, but the ecological niches occupied by an organism provide some indication of the relative magnitude of these forces. here, by analyzing 384 bacterial genomes assigned to three ecological categories (obligate intracellular, facultative intracellular, and ex ...201020577742
mast cells in allergy and infection: versatile effector and regulatory cells in innate and adaptive immunity.mast cells are widely distributed in tissues, particularly near surfaces exposed to the environment. mast cells can be activated to secrete diverse mediators and cytokines by ige and specific ag and many other stimuli, including products derived from either pathogens or the host during innate immune responses. although mast cells are best known for their role in ige-associated allergic disorders, mast cells can also exacerbate models of autoimmunity, enhance the sensitization and/or effector pha ...020583030
results from a mathematical model for human monocytic ehrlichiosis. 200920584161
a quantitative comparison of two sample methods for collecting amblyomma americanum and dermacentor variabilis (acari: ixodidae) in studies of tick communities, sampling methodology may influence observed patterns. the objective of this study was to compare two sampling methods, dragging and dry ice baiting, in two habitats to assess abundance of off-host ticks. tick communities were monitored from march to december in a forested and an old-field habitat in northeast missouri. in each habitat, eight drag and eight dry ice bait samples were collected every 2 weeks on a permanent grid. the most common ticks collected were a ...201020585839
beauveria bassiana (ascomycota: hypocreales) as a management agent for free-living amblyomma americanum (acari: ixodidae) in ohio.unfed adult amblyomma americanum were exposed to the entomopathogenic fungus beauveria bassiana and placed in the field. ticks exposed to the fungus experienced higher mortality than those in the control group (p = 0.001). it is recommended that for inclusion in a tick management program, the fungus be applied in the late evening during the months march through june as this is when ticks are most active and conditions suitable for fungal activity occur.201120607363
effects of a lone star tick (amblyomma americanum) burden on performance and metabolic indicators in growing beef steers.we examined the response of selected animal performance, endocrine, immune, and metabolic factors from 13 steers (254+/-6.1 kg) with and without a lone star (amblyomma americanum) tick burden during progressive days of the tick feeding cycle. steers were randomly assigned to either non-treated controls or treated with 300 adult pair of a. americanum per animal. animals were weighed and blood sampled on days -7, 0, 10, 14, 21, 28, and 35 relative to tick treatment. tick treatment did not affect ( ...201020609519
detection of lyme disease spirochete, borrelia burgdorferi sensu lato, including three novel genotypes in ticks (acari: ixodidae) collected from songbirds (passeriformes) across canada.lyme disease is reported across canada, but pinpointing the source of infection has been problematic. in this three-year, bird-tick-pathogen study (2004-2006), 366 ticks representing 12 species were collected from 151 songbirds (31 passerine species/subspecies) at 16 locations canada-wide. of the 167 ticks/pools tested, 19 (11.4%) were infected with borrelia burgdorferi sensu lato (s.l.). sequencing of the rrf-rrl intergenic spacer gene revealed four borrelia genotypes: b. burgdorferi sensu stri ...201020618658
r2 dynamics in triops cancriformis (bosc, 1801) (crustacea, branchiopoda, notostraca): turnover rate and 28s concerted evolution.the r2 retrotransposon is here characterized in bisexual populations of the european crustacean triops cancriformis. the isolated element matches well with the general aspects of the r2 family and it is highly differentiated from that of the congeneric north american triops longicaudatus. the analysis of 5' truncations indicates that r2 dynamics in t. cancriformis populations show a high turnover rate as observed in drosophila simulans. for the first time in the literature, though, individuals h ...201020628416
comparative microarray analysis of rhipicephalus (boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on bos indicus and bos taurus cattle.rhipicephalus (boophilus) microplus is an obligate blood feeder which is host specific to cattle. existing knowledge pertaining to the host or host breed effects on tick transcript expression profiles during the tick - host interaction is poor.201020637126
an insight into the sialotranscriptome of the brown dog tick, rhipicephalus sanguineus.rhipicephalus sanguineus, known as the brown dog tick, is a common ectoparasite of domestic dogs and can be found worldwide. r.sanguineus is recognized as the primary vector of the etiological agent of canine monocytic ehrlichiosis and canine babesiosis. here we present the first description of a r. sanguineus salivary gland transcriptome by the production and analysis of 2,034 expressed sequence tags (est) from two cdna libraries, one consctructed using mrna from dissected salivary glands from ...201020650005
phylogenetic position of the acariform mites: sensitivity to homology assessment under total evidence.mites (acari) have traditionally been treated as monophyletic, albeit composed of two major lineages: acariformes and parasitiformes. yet recent studies based on morphology, molecular data, or combinations thereof, have increasingly drawn their monophyly into question. furthermore, the usually basal (molecular) position of one or both mite lineages among the chelicerates is in conflict to their morphology, and to the widely accepted view that mites are close relatives of ricinulei.201020678229
formulations of deet, picaridin, and ir3535 applied to skin repel nymphs of the lone star tick (acari: ixodidae) for 12 hours.the efficacies of a 20% 1-methyl-propyl-2- (hydroxyethyl)-1-piperidinecarboxylate (picaridin) spray, 20% 3-(n-acetyl-n-butyl)aminopropionic acid ethyl ester (ir3535) spray, 20% picaridin lotion, 10% ir3535 lotion, and 33% n,n-diethyl-3-methylbenzamide (deet) cream in repelling nymphal lone star ticks, amblyomma americanum (l.), were determined at 2-h intervals over 12 h using human subjects. a repellent formulation was applied in a 5-cm-wide band encircling a volunteer's lower leg. for each chal ...201020695288
absence of rickettsia rickettsii and occurrence of other spotted fever group rickettsiae in ticks from tennessee.rocky mountain spotted fever (rmsf) is the most common tick-borne illness in tennessee. little is known about the occurrence of r. rickettsii, the causative agent, in ticks in tennessee. to better understand the prevalence and distribution of rickettsial agents in ticks, we tested 1,265 amblyomma, dermacentor, and ixodes adult and nymphal ticks. additionally, we tested 231 amblyomma americanum larvae. ticks were collected from 49 counties from humans, wild animals, domestic canines, and flannel ...201020810834
preparing the "new" biologist of the future: student research at the interface of mathematics and biology.we describe a unique research experience for undergraduates and research experience for veterinary students summer program at the national institute for mathematical and biological synthesis on the campus of the university of tennessee, knoxville. the program focused on interdisciplinary research at the interface of biology and mathematics. participants were selected to work on projects with a biology mentor and a mathematics mentor in an environment that promoted collaboration outside of the st ...201020810963
progress and obstacles in vaccine development for the ehrlichioses.ehrlichia are tick-borne obligately intracellular bacteria that cause significant diseases in veterinary natural hosts, including livestock and companion animals, and are now considered important zoonotic pathogens in humans. vaccines are needed for these veterinary and zoonotic human pathogens, but many obstacles exist that have impeded their development. these obstacles include understanding genetic and antigenic variability, influence of the host on the pathogen phenotype and immunogenicity, ...201020822349
efficacy of a doxycycline treatment regimen initiated during three different phases of experimental ehrlichiosis.doxycycline is the treatment of choice for canine monocytic ehrlichiosis (cme), a well-characterized disease and valuable model for tick-borne zoonoses. conflicting reports of clearance of ehrlichia canis after treatment with doxycycline suggested that the disease phase during which treatment is initiated influences outcomes of these treatments. the purpose of this study was to evaluate the efficacy of a 28-day doxycycline regimen for clearance of experimental e. canis infections from dogs treat ...201020921310
invasive honeysuckle eradication reduces tick-borne disease risk by altering host dynamics.despite the ubiquity of invasive organisms and their often deleterious effects on native flora and fauna, the consequences of biological invasions for human health and the ecological mechanisms through which they occur are rarely considered. here we demonstrate that a widespread invasive shrub in north america, amur honeysuckle (lonicera maackii), increases human risk of exposure to ehrlichiosis, an emerging infectious disease caused by bacterial pathogens transmitted by the lone star tick (ambl ...201020937859
confirmation of amblyomma americanum (acari: ixodidae) as a vector for cytauxzoon felis (piroplasmorida: theileriidae) to domestic cats.amblyomma americanum was confirmed as a competent vector in the transmission of cytauxzoon felis to domestic cats. infection with c. felis was produced and replicated in four domestic felines by the bite of a. americanum adults that were acquisition fed as nymphs on a domestic cat that survived cytauxzoonosis. numerous attempts to transmit c. felis with dermacentor variabilis at the same time were not successful. all cats upon which infected a. americanum were transmission fed exhibited disease ...201020939386
physiological effects upon amblyomma americanum (acari: ixodidae) infected with beauveria bassiana (ascomycota: hypocreales).unfed adult amblyomma americanum were exposed to the entomopathogenic fungus beauveria bassiana. ticks exposed to the fungus exhibited reduced survival and increased water loss as indicated by change in weight. treated ticks survived 7.2 ± 0.22 days (mean ± se) and controls survived 17.9 ± 0.73 days (p = 0.01; df = 57). at death, ticks exposed to the fungus had lost 25.2 ± 0.84% of their starting weight; control ticks had lost 14.1 ± 0.85% of their starting weight (p = 0.01; df = 96). water loss ...201020957415
genomic survey of the ectoparasitic mite varroa destructor, a major pest of the honey bee apis mellifera.the ectoparasitic mite varroa destructor has emerged as the primary pest of domestic honey bees (apis mellifera). here we present an initial survey of the v. destructor genome carried out to advance our understanding of varroa biology and to identify new avenues for mite control. this sequence survey provides immediate resources for molecular and population-genetic analyses of varroa-apis interactions and defines the challenges ahead for a comprehensive varroa genome project.201020973996
arbobacteria - pathogens transmittable by arthropods. 200921048822
distribution and prevalence of cytauxzoon felis in bobcats (lynx rufus), the natural reservoir, and other wild felids in thirteen states.cytauxzoon felis, a protozoan parasite of wild and domestic felids, is the causative agent of cytauxzoonosis in domestic and some exotic felids in the united states. the bobcat (lynx rufus) is the natural reservoir for this parasite, but other felids such as florida panthers (puma concolor coryii) and domestic cats may maintain long-term parasitemias and serve as reservoirs. experimentally, two tick species, dermacentor variabilis and amblyomma americanum, have demonstrated the ability to transm ...201021071149
first report of the repellency of 2-tridecanone against ticks.2-tridecanone and 2-undecanone are both found naturally in the trichomes of wild tomato plants and are important in plant resistance to herbivory. 2-undecanone is the u.s. environmental protection agency (epa)-registered active ingredient in the commercially available arthropod repellent, bioud(®) . the goal of this study was to examine the tick repellency of 2-tridecanone. two-choice bioassays were conducted using 8% 2-tridecanone vs. the repellent carrier (absolute ethanol) and compared with t ...201021073492
development of loop-mediated isothermal amplification (lamp) assays for rapid detection of ehrlichia ruminantium.the rickettsial bacterium ehrlichia ruminantium is the causative agent of heartwater, a potential zoonotic disease of ruminants transmitted by ticks of the genus amblyomma. the disease is distributed in nearly all of sub-saharan africa and some islands of the caribbean, from where it threatens the american mainland. this report describes the development of two different loop-mediated isothermal amplification (lamp) assays for sensitive and specific detection of e. ruminantium.201021087521
novel field assays and the comparative repellency of bioud(®) , deet and permethrin against amblyomma americanum.two new field bioassay methods were developed to compare the repellent activity of bioud(®) (containing 7.75% 2-undecanone), 98.1% deet and 0.5% permethrin against natural populations of nymphal amblyomma americanum (l.) (acari: ixodidae). in a cloth sheet assay, pieces of material measuring 41 × 58 cm, separately treated with one of the test materials or the appropriate solvent carrier, were placed at random on the ground and baited with dry ice for 1 h. mean numbers of ticks on repellent-treat ...201021118283
rabbit tularemia and hepatic coccidiosis in wild rabbit. 201021122253
do noxious neighbors spread disease? 021123147
infrequency of rickettsia rickettsii in dermacentor variabilis removed from humans, with comments on the role of other human-biting ticks associated with spotted fever group rickettsiae in the united states.abstract from 1997 to 2009, the tick-borne disease laboratory of the u.s. army public health command (usaphc) (formerly the u.s. army center for health promotion and preventive medicine) screened 5286 dermacentor variabilis ticks removed from department of defense (dod) personnel, their dependents, and dod civilian personnel for spotted fever group rickettsiae using polymerase chain reaction and restriction fragment length polymorphism analysis. rickettsia montanensis (171/5286 = 3.2%) and ricke ...201021142953
high-prevalence borrelia miyamotoi [scapin wild turkeys (meleagris gallopavo) in tennessee.during spring and fall 2009, 60 wild turkeys (meleagris gallopavo) harvested by tennessee hunters were surveyed for borrelia spp. by sampling their blood, tissue, and attached ticks. in both seasons, 70% of turkeys were infested with juvenile amblyomma americanum; one spring turkey hosted an adult female ixodes brunneus. polymerase chain reaction assays followed by dna sequencing indicated that 58% of the turkeys were positive for the spirochete borrelia miyamotoi, with tissue testing positive m ...201021175079
assessment of bacterial diversity in the cattle tick rhipicephalus (boophilus) microplus through tag-encoded pyrosequencing.ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. the cattle tick, rhipicephalus (boophilus) microplus, hinders livestock production in tropical and subtropical parts of the world where it is endemic. tick microbiomes remain largely unexplored. the objective of this study was to explore the r. microplus microbiome by applying the bacterial 16s tag-encoded flx-titanium amplicon pyrosequencing (btefap) technique to characterize its bacterial ...201121211038
amblyomma americanum (l.) (acari: ixodidae) tick salivary gland serine protease inhibitor (serpin) 6 is secreted into tick saliva during tick order to successfully feed and transmit disease agents, ticks are thought to inject serine protease inhibitors (serpins) into the host to modulate host defense responses to tick feeding, such as inflammation, the complement activation pathway and blood coagulation. in this study, we show that amblyomma americanum (aam) serpin (s) 6 is putatively injected into the host during tick feeding, in that the antibody to recombinant (r) aams6 specifically reacted with the expected ~43/45 kda aams6 pro ...201121270316
rna interference in ticks.ticks are obligate hematophagous ectoparasites of wild and domestic animals and humans, and are considered to be second worldwide to mosquitoes as vectors of human diseases(1) and the most important vectors affecting cattle industry worldwide(2). ticks are classified in the subclass acari, order parasitiformes, suborder ixodida and are distributed worldwide from arctic to tropical regions(3). despite efforts to control tick infestations, these ectoparasites remain a serious problem for human and ...201121304465
a further insight into the sialome of the tropical bont tick, amblyomma variegatum.ticks--vectors of medical and veterinary importance--are themselves also significant pests. tick salivary proteins are the result of adaptation to blood feeding and contain inhibitors of blood clotting, platelet aggregation, and angiogenesis, as well as vasodilators and immunomodulators. a previous analysis of the sialotranscriptome (from the greek sialo, saliva) of amblyomma variegatum is revisited in light of recent advances in tick sialomes and provides a database to perform a proteomic study ...201121362191
an acarologic survey and amblyomma americanum distribution map with implications for tularemia risk in the united states, tickborne diseases occur focally. missouri represents a major focus of several tickborne diseases that includes spotted fever rickettsiosis, tularemia, and ehrlichiosis. our study sought to determine the potential risk of human exposure to human-biting vector ticks in this area. we collected ticks in 79 sites in southern missouri during june 7-10, 2009, which yielded 1,047 adult and 3,585 nymphal amblyomma americanum, 5 adult amblyomma maculatum, 19 adult dermacentor variab ...201121363979
the afhsc-division of geis operations predictive surveillance program: a multidisciplinary approach for the early detection and response to disease outbreaks.the armed forces health surveillance center, division of global emerging infections surveillance and response system operations (afhsc-geis) initiated a coordinated, multidisciplinary program to link data sets and information derived from eco-climatic remote sensing activities, ecologic niche modeling, arthropod vector, animal disease-host/reservoir, and human disease surveillance for febrile illnesses, into a predictive surveillance program that generates advisories and alerts on emerging infec ...201121388561
experimental primary and secondary infections of domestic dogs with ehrlichia this study, the infection dynamics of ehrlichia ewingii, causative agent of granulocytotropic ehrlichiosis in dogs and humans, was examined in experimentally infected dogs by using a combination of physical examination, hematologic and biochemical analyses, and molecular and serologic assays. for the experimental trials, blood from an e. ewingii-infected dog was inoculated intravenously into two na+»ve dogs and two dogs with prior experimental exposure to e. ewingii (both were negative for e. ...201121397411
anointing chemicals and hematophagous arthropods: responses by ticks and mosquitoes to citrus (rutaceae) peel exudates and monoterpene components.some birds and mammals roll on or wipe themselves with the fruits or leaves of citrus spp. or other rutaceae. these anointing behaviors, as with anointing in general, are thought to function in the topical acquisition of chemicals that deter consumers, including hematophagous arthropods. we measured avoidance and other responses by nymphal lone star ticks (amblyomma americanum) and adult female yellow fever mosquitoes (aedes aegypti) to lemon peel exudate and to 24 volatile monoterpenes (racemat ...201121409496
distribution and molecular characterization of wolbachia endosymbionts and filarial nematodes in maryland populations of the lone star tick (amblyomma americanum).the lone star tick amblyomma americanum is host to a wide diversity of endosymbiotic bacteria. we identified a novel wolbachia symbiont infecting a. americanum. multilocus sequence typing phylogenetically placed the endosymbiont in the increasingly diverse f supergroup. we assayed a total of 1031 ticks (119 females, 78 males and 834 nymphs in 89 pools) from 16 maryland populations for infection. infection frequencies in the natural populations were approximately 5% in females and <2% (minimum in ...201121410491
the relevance of tick bites to the production of ige antibodies to the mammalian oligosaccharide galactose-a-1, 2009, we reported a novel form of delayed anaphylaxis to red meat that is related to serum ige antibodies to the oligosaccharide galactose-a-1,3-galactose (alpha-gal). most of these patients had tolerated meat for many years previously. the implication is that some exposure in adult life had stimulated the production of these ige antibodies.201121453959
susceptibility of four tick species, amblyomma americanum, dermacentor variabilis, ixodes scapularis, and rhipicephalus sanguineus (acari: ixodidae), to nootkatone from essential oil of grapefruit.toxicity of nootkatone was determined in laboratory assays against unfed nymphs of amblyomma americanum l., dermacentor variabilis (say), ixodes scapularis say, and rhipicephalus sanguineus latreille. we determined the 50% lethal concentration (lc50) and 90% lethal concentration (lc90) of nootkatone by recording tick mortality 24 h after exposure in treated glass vials. nymphs were susceptible to nootkatone with lc50 values of 0.352, 0.233, 0.169, and 0.197 microg/cm2, and lc90 values of 1.001, ...201121485368
efficacy of spinosad against acaricide-resistant and -susceptible rhipicephalus (boophilus) microplus and acaricide-susceptible amblyomma americanum and dermacentor variabilis.various acaricide-resistant strains of rhipicephalus (boophilus) microplus, representative of the major resistance mechanisms found in mexico and brazil, were exposed to spinosad using the food and agriculture organization of the united nations larval packet test and adult immersion test (ait). larvae of all strains tested were found to be susceptible to spinosad. conversely, spinosad did not show toxic activity toward engorged females used in the ait. in vitro tests against larvae, nymphs, and ...201121485374
rickettsia rickettsii (rickettsiales: rickettsiaceae) in amblyomma americanum (acari: ixodidae) from kansas.the role of lone star ticks as vectors for rocky mountain spotted fever (rmsf) remains poorly described. we compared the entomological inoculation rates (eirs) for rickettsia spp. for representative sites in missouri and kansas, states that frequently report rmsf each year. host-seeking ticks were collected during 2006 and pooled tick homogenates analyzed by polymerase chain reaction to detect probable r. rickettsii, with confirmation for multiple gene targets performed on individual ticks from ...201121485390
the immunopathology of canine vector-borne diseases.abstract: the canine vector-borne infectious diseases (cvbds) are an emerging problem in veterinary medicine and the zoonotic potential of many of these agents is a significant consideration for human health. the successful diagnosis, treatment and prevention of these infections is dependent upon firm understanding of the underlying immunopathology of the diseases in which there are unique tripartite interactions between the microorganism, the vector and the host immune system. although signific ...201121489234
tick-borne encephalitis virus in dogs - is this an issue?abstract: the last review on tick-borne encephalitis (tbe) in dogs was published almost ten years ago. since then, this zoonotic tick-borne arbovirus has been geographically spreading and emerging in many regions in eurasia and continues to do so. dogs become readily infected with tbe virus but they are accidental hosts not capable to further spread the virus. they seroconvert upon infection but they seem to be much more resistant to the clinical disease than humans. apart from their use as sent ...201121489255
suppression of host-seeking ixodes scapularis and amblyomma americanum (acari: ixodidae) nymphs after dual applications of plant-derived acaricides in new jersey.we evaluated the ability of dual applications of natural, plant-derived acaricides to suppress nymphal ixodes scapularis say and amblyomma americanum (l.) (acari: ixodidae) in a lyme disease endemic area of new jersey. an aqueous formulation of 2% nootkatone provided >90% control of i. scapularis through 7 d. control declined to 80.9% at 14 d, and a second application was made that provided >95% control through the remaining 4 wk of the nymphal season. nootkatone provided >90% control of a. amer ...201121510219
arbobacteria - pathogens transmittable by arthropods. 200821512627
isolation and characterization of ehrlichia chaffeensis rna polymerase and its use in evaluating p28 outer membrane protein gene promoters.abstract:201121513529
rickettsia rickettsii transmission by a lone star tick, north carolina.only indirect or circumstantial evidence has been published to support transmission of rickettsia rickettsii by amblyomma americanum (lone star) ticks in north america. this study provides molecular evidence that a. americanum ticks can function, although most likely infrequently, as vectors of rocky mountain spotted fever for humans.201121529399
a snapshot of the ixodes scapularis degradome.parasitic encoded proteases are essential to regulating interactions between parasites and their hosts and thus they represent attractive anti-parasitic druggable and/or vaccine target. we have utilized annotations of ixodes scapularis proteases in gene bank and version 9.3 merops database to compile an index of at least 233 putatively active and 150 putatively inactive protease enzymes that are encoded by the i. scapularis genome. the 233 putatively active protease homologs hereafter referred t ...201121596113
basophils, ige, and autoantibody-mediated kidney disease.basophils are of interest in immunology due to their ability to produce a th2-signature cytokine, il-4, following activation. a new understanding of the role of basophils in immunity shows novel functions at a cellular level through which basophils influence adaptive immunity. this review summarizes new advances in basophil biology and discusses new roles for basophils in human disease, especially in the mediation of the pathogenesis of lupus nephritis. recently, basophils have been shown to con ...201121597041
coxiella symbionts in the cayenne tick amblyomma cajennense.members of the coxiella genus are intracellular bacteria that can infect a variety of animals including humans. a symbiotic coxiella was recently described in amblyomma americanum ticks in the northern hemisphere with no further investigations of other amblyomma species in other geographic regions. these ixodid ticks represent a group of important vectors for human infectious agents. in the present work, we have demonstrated that symbiotic coxiella (scox) are widespread, occurring in south ameri ...201121611689
differential mortality of dog tick vectors due to infection by diverse francisella tularensis tularensis genotypes.abstract the factors involved in the long-term perpetuation of francisella tularensis tularensis in nature are poorly understood. martha's vineyard, massachusetts, has become a site of sustained transmission of type a tularemia, with nearly 100 human cases reported from 2000 to 2010. we have identified a stable focus of f. tularensis transmission there, where the annual prevalence in host-seeking dermacentor variabilis is about 3%, suggesting that this tick perpetuates the agent. however, labora ...201121612530
francisella tularensis molecular typing using differential insertion sequence amplification (disa).tularemia is a potentially fatal disease that is caused by the highly infectious and zoonotic pathogen francisella tularensis. despite the monomorphic nature of sequenced f. tularensis genomes, there is a significant degree of plasticity in the organization of genetic elements. the observed variability in these genomes is primarily due to the transposition of direct repeats and insertion sequence (is) elements. since current methods used to genotype f. tularensis are time-consuming and require e ...201121613430
efficacy of dry ice-baited traps for sampling amblyomma americanum (acari: ixodidae) varies with life stage but not habitat.the carbon dioxide-baited trap is the most common and effective method for sampling vector life-stage amblyomma americanum (l.) (acari: ixodidae), although confounding environmental variables are rarely considered. a mark-recapture experiment was designed to compare recapture proportions of a. americanum nymphs and adults between two habitat types: old field and oak-hickory forest. powdered fluorescent dye was used to mark a. americanum ticks released in 1-m increments from carbon dioxide-baited ...201121661336
toward an understanding of the perpetuation of the agent of tularemia.the epidemiology of tularemia has influenced, perhaps incorrectly skewed, our views on the ecology of the agent of tularemia. in particular, the central role of lagomorphs needs to be reexamined. diverse observations, some incidental, and some that are more generally reproducible, have not been synthesized so that the critical elements of the perpetuation of francisella tularensis can be identified. developing a quantitative model of the basic reproduction number of f. tularensis may require sep ...201121687803
increasing incidence of ehrlichia chaffeensis and anaplasma phagocytophilum in the united states, 2000-2007.ehrlichia chaffeensis causes human monocytic ehrlichiosis, and anaplasma phagocytophilum causes human granulocytic anaplasmosis. these related tick-borne rickettsial organisms can cause severe and fatal illness. during 2000-2007, the reported incidence rate of e. chaffeensis increased from 0.80 to 3.0 cases/million persons/year. the case-fatality rate was 1.9%, and the hospitalization rate was 49%. during 2000-2007, the reported incidence of a. phagocytophilum increased from 1.4 to 3.0 cases/mil ...201121734137
mechanisms of obligatory intracellular infection with anaplasma phagocytophilum.anaplasma phagocytophilum persists in nature by cycling between mammals and ticks. human infection by the bite of an infected tick leads to a potentially fatal emerging disease called human granulocytic anaplasmosis. a. phagocytophilum is an obligatory intracellular bacterium that replicates inside mammalian granulocytes and the salivary gland and midgut cells of ticks. a. phagocytophilum evolved the remarkable ability to hijack the regulatory system of host cells. a. phagocytophilum alters vesi ...201121734244
the complexity of rhipicephalus (boophilus) microplus genome characterised through detailed analysis of two bac clones.abstract: background: rhipicephalus (boophilus) microplus (rmi) a major cattle ectoparasite and tick borne disease vector, impacts on animal welfare and industry productivity. in arthropod research there is an absence of a complete chelicerate genome, which includes ticks, mites, spiders, scorpions and crustaceans. model arthropod genomes such as drosophila and anopheles are too taxonomically distant for a reference in tick genomic sequence analysis. this study focuses on the de-novo assembly of ...201121777481
efficacy of a novel topical combination of fipronil, amitraz and (s)-methoprene for treatment and control of induced infestations with four north american tick species (dermacentor variabilis, ixodes scapularis, amblyomma americanum and amblyomma maculatum) on dogs.five laboratory studies were conducted to confirm that a single topical dose of the novel combination of fipronil, amitraz and (s)-methoprene, certifect™ (merial limited, ga, usa), is efficacious for the rapid control of pre-existing infestations and the prevention of new infestations with ixodes scapularis, dermacentor variabilis, amblyomma americanum and amblyomma maculatum for at least 28 days on dogs. in each study, 8 male and 8 female purpose-bred, laboratory beagles were randomly assigned ...201121777734
generation, analysis and functional annotation of expressed sequence tags from the ectoparasitic mite psoroptes ovis.abstract: background: sheep scab is caused by psoroptes ovis and is arguably the most important ectoparasitic disease affecting sheep in the uk. the disease is highly contagious and causes and considerable pruritis and irritation and is therefore a major welfare concern. current methods of treatment are unsustainable and in order to elucidate novel methods of disease control a more comprehensive understanding of the parasite is required. to date, no full genomic dna sequence or large scale trans ...201121781297
emergence of a new pathogenic ehrlichia species, wisconsin and minnesota, 2009.ehrlichiosis is a clinically important, emerging zoonosis. only ehrlichia chaffeensis and e. ewingii have been thought to cause ehrlichiosis in humans in the united states. patients with suspected ehrlichiosis routinely undergo testing to ensure proper diagnosis and to ascertain the cause.201121812671
comparative analysis of hemocyte phagocytosis between six species of arthropods as measured by flow cytometry.phagocytosis of pathogens by hemocytes is a rapid-acting immune response and represents a primary means of limiting microbial infection in some species of arthropods. to survey the relative capacity of hemocyte phagocytosis as a function of the arthropod immune response, we examined the extent of phagocytosis among a wide taxonomic range of arthropod species including a decapod crustacean (litopenaeus vannamei), three ixodid tick species (amblyomma americanum, dermacentor variabilis, and ixodes ...201121843526
An insight into the sialotranscriptome and proteome of the coarse bontlegged tick, Hyalomma marginatum rufipes.Ticks are mites specialized in acquiring blood from vertebrates as their sole source of food and are important disease vectors to humans and animals. Among the specializations required for this peculiar diet, ticks evolved a sophisticated salivary potion that can disarm their host's hemostasis, inflammation, and immune reactions. Previous transcriptome analysis of tick salivary proteins has revealed many new protein families indicative of fast evolution, possibly due to host immune pressure. The ...201121851864
Displaying items 701 - 800 of 1263