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rabbit tularemia and hepatic coccidiosis in wild rabbit. 201021122253
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
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
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
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
arbobacteria - pathogens transmittable by arthropods. 200921048822
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
a quantitative comparison of two sample methods for collecting amblyomma americanum and dermacentor variabilis (acari: ixodidae) in missouri.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
results from a mathematical model for human monocytic ehrlichiosis. 200920584161
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
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
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
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
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
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
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
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
sdetection of vector-borne agents in lone star ticks, amblyomma americanum (acari: ixodidae), from mississippi.in 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
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
bacterial pathogens in ixodid ticks from a piedmont county in north carolina: prevalence of rickettsial organisms.in 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
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 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
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
rite of amblyomma americanum associated with possible tick paralysis. 194720340890
infestation of a raccoon by amblyomma americanum. 194720264533
insecticides to control the european corn borer in field corn. 194720264508
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
meeting the challenges of on-host and off-host water balance in blood-feeding arthropods.in 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
borrelia, ehrlichia, and rickettsia spp. in ticks removed from persons, texas, usa.data 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
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
potential for tick-borne bartonelloses.as 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
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
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
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
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
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
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
[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
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
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
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
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
molecular and clinical evidence of ehrlichia chaffeensis infection in cameroonian patients with undifferentiated febrile illness.in 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
larval keys to the genera of ixodidae (acari) and species of ixodes (latreille) ticks established in california.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
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
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
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
ehrlichia chaffeensis infection of sika deer, japan.to 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
strains of ehrlichia chaffeensis in southern indiana, kentucky, mississippi, and north carolina.rates of infection of amblyomma americanum (l.) by ehrlichia chaffeensis were compared in 100 ticks collected from sites in each of four states: indiana, north carolina, kentucky, and mississippi. the overall infection rates were similar among sites, ranging from 1 to 4%. because pathogenic differences may exist between e. chaffeensis strains, nested polymerase chain reaction (pcr) amplification of the variable-length pcr target (vlpt), and sequencing of the amplicons were performed to different ...200919960699
burden of tick-borne infections on american companion animals.this review examines the biology of ticks and tick-borne infections in the united states. the most common tick-borne diseases in dogs and cats are discussed. we demonstrate that there is much interest in tick-borne infections at the level of the lay public (pet owners), describe trends in the distribution and prevalence of tick-borne infections in the united states, summarize some issues in understanding the degree of ill health due to tick-borne infections, and suggest some avenues for research ...200919945085
prevalence of ehrlichia chaffeensis and ehrlichia ewingii in ticks from tennessee.human ehrlichiosis is the second most common tick-borne disease reported in tennessee after rocky mountain spotted fever. two closely related ehrlichiae, ehrlichia chaffeensis and ehrlichia ewingii, are both causative agents of human disease and are transmitted by amblyomma americanum, the lone star tick. prevalence rates and distribution patterns of these pathogens among ticks in tennessee are currently unknown. to understand prevalence and exposure risk of ehrlichia spp., we tested 616 ticks ( ...201019877819
molecular detection of rickettsia amblyommii in amblyomma americanum parasitizing humans.a quantitative real-time polymerase chain reaction assay to detect and quantify a portion of the outer membrane protein b gene (ompb) of rickettsia amblyommii was employed to assess the threat of r. amblyommii exposure to humans parasitized by amblyomma americanum (the lone star tick). a total of 72 pools of lone star ticks removed from humans were acquired from two collections and used in this study: 44 pools of a. americanum submitted to the department of defense human tick test kit program in ...201019877809
distribution of antibodies reactive to borrelia lonestari and borrelia burgdorferi in white-tailed deer (odocoileus virginianus) populations in the eastern united states.southern tick-associated rash illness is a lyme-like syndrome that occurs in the southern states. borrelia lonestari, which has been suggested as a possible causative agent of southern tick-associated rash illness, naturally infects white-tailed deer (wtd; odocoileus virginianus) and is transmitted by the lone star tick (amblyomma americanum). to better understand the prevalence and distribution of borrelia exposure among wtd, we tested wtd from 21 eastern states for antibodies reactive to b. lo ...200919874183
molecular events involved in cellular invasion by ehrlichia chaffeensis and anaplasma phagocytophilum.ehrlichia chaffeensis and anaplasma phagocytophilum are obligatory intracellular bacteria that preferentially replicate inside leukocytes by utilizing biological compounds and processes of these primary host defensive cells. these bacteria incorporate cholesterol from the host for their survival. upon interaction with host monocytes and granulocytes, respectively, these bacteria usurp the lipid raft domain containing gpi-anchored protein to induce a series of signaling events that result in inte ...201019836896
natural history of ehrlichia chaffeensis: vertebrate hosts and tick vectors from the united states and evidence for endemic transmission in other countries.ehrlichia chaffeensis, an intracellular gram-negative zoonotic bacterium, is the causative agent of human monocytotropic ehrlichiosis (hme). in humans, the disease can range from a mild, non-specific illness with few to no clinical signs to a moderately severe to fatal disease, especially those with compromised immune systems. e. chaffeensis is maintained in a complex cycle involving white-tailed deer (wtd; odocoileus virginianus) as a primary reservoir and the lone star tick (lst; amblyomma ame ...201019819631
comparative efficacy of bioud to other commercially available arthropod repellents against the ticks amblyomma americanum and dermacentor variabilis on cotton cloth.bioud is an arthropod repellent that contains the active ingredient 2-undecanone originally derived from wild tomato plants. repellency of bioud was compared with five commercially available arthropod repellents against the ticks amblyomma americanum (l.) and dermacentor variabilis say in two-choice bioassays on treated versus untreated cotton cheesecloth. overall mean percentage repellency against both species was greatest for and did not differ significantly between bioud (7.75% 2-undecanone) ...200919815887
rickettsia parkeri in amblyomma americanum ticks, tennessee and georgia, usa.to determine the geographic distribution of the newly recognized human pathogen rickettsia parkeri, we looked for this organism in ticks from tennessee and georgia, usa. using pcr and sequence analysis, we identified r. parkeri in 2 amblyomma americanum ticks. this rickettsiosis may be underdiagnosed in the eastern united states.200919788817
macrophage migration inhibitory factor expression and protein localization in amblyomma americanum (ixodidae).amblyomma americanum (l.) ticks continue to emerge as disease vectors in many areas of the united states. tick macrophage migration inhibitory factor (mif) was first identified in a. americanum females and has been demonstrated to inhibit macrophage movement to the same extent as human mif. this study was conducted to further characterize and elucidate the physiological role for mif in tick feeding. a relative quantitative pcr assay was developed to determine the level of mif gene expression dur ...201019784782
anaplasmosis and ehrlichiosis - maine, 2008.anaplasmosis and ehrlichiosis are rickettsial tickborne diseases that have had at least a twofold increase in prevalence in the united states since 2000. despite similar clinical presentations, the causative organisms are carried by different ticks with distinct geographic and ecologic associations. surveillance efforts are complicated by ambiguous terminology and serologic testing with antibody cross-reactivity. although anaplasmosis historically has been reported in maine, ehrlichiosis has bee ...200919779398
sensitivity of host-seeking nymphal lone star ticks (acari: ixodidae) to immersion in heated water.host-seeking nymphal amblyomma americanum (l.) (acari: ixodidae) were placed into heated water, and their survival or their torpidity was recorded as a function of exposure time. exposures were determined that either kill the nymphs or affect their mobility. all nymphs died when exposed for a minute or more to a temperature > 51 degrees c. nearly all nymphs remained motionless for a period of time when exposed for 3 min to a temperature > 44 degrees c.200919769061
influence of prescribed burns on the abundance of amblyomma americanum (acari: ixodidae) in the missouri ozarks.the increasingly widespread use of prescribed burns to manage oak (quercus spp.)-hickory (carya spp.) forests in the missouri ozarks, usa, has considerable potential to alter the abundance of amblyomma americanum (l.) (acari: ixodidae), the lone star tick, an important vector of several emerging pathogens. in particular, responses of important tick hosts, primarily white-tailed deer (odocoileus virginianus), to fire management and the resultant changes in the distribution and abundance of a. ame ...200919769033
efficacy of a topical ectoparasiticide containing dinotefuran, pyriproxyfen, and permethrin against amblyomma americanum (lone star tick) and amblyomma maculatum (gulf coast tick) on dogs.amblyomma americanum (lone star tick) and amblyomma maculatum (gulf coast tick) are important disease vectors for both dogs and humans. this article describes two studies conducted to evaluate the efficacy of a new topical spot-on ectoparasiticide containing dinotefuran, permethrin, and pyriproxyfen (vectra 3d, summit vetpharm) against a. maculatum and a. americanum in dogs. dogs were treated on day 0 and infested on days -1, 7, 14, 21, and 28 with approximately 40 ticks each day. live tick coun ...200919742444
assessment of polymicrobial infections in ticks in new york state.ixodes scapularis ticks are clinically important hematophagous vectors. a single tick bite can lead to a polymicrobial infection. we determined the prevalence of polymicrobial infection with borrelia burgdorferi, anaplasma phagocytophilum, babesia microti, borrelia miyamotoi, and powassan virus in 286 adult ticks from the two counties in new york state where lyme disease is endemic, utilizing a masstag multiplex polymerase chain reaction assay. seventy-one percent of the ticks harbored at least ...201019725770
directed evolution of a filamentous fungus for thermotolerance.filamentous fungi are the most widely used eukaryotic biocatalysts in industrial and chemical applications. consequently, there is tremendous interest in methodology that can use the power of genetics to develop strains with improved performance. for example, metarhizium anisopliae is a broad host range entomopathogenic fungus currently under intensive investigation as a biologically based alternative to chemical pesticides. however, it use is limited by the relatively low tolerance of this spec ...200919709419
predominance of ehrlichia chaffeensis in rhipicephalus sanguineus ticks from kennel-confined dogs in limbe, cameroon.rhipicephalus sanguineus ticks (n = 63) collected from five dogs (two adults and three puppies) housed in a kennel were screened for ehrlichial agents (ehrlichia canis, e. chaffeensis, and e. ewingii) using a species-specific multicolor real-time taqman pcr amplification of the disulphide bond formation protein (dsb) gene. ehrlichia chaffeensis dna was detected in 33 (56%) ticks, e. canis dna was detected in four (6%) ticks, and one tick was coinfected. the e. chaffeensis and e. canis nucleotide ...201019693681
ehrlichia chaffeensis infections in drosophila melanogaster.ehrlichia chaffeensis is an obligate, intracellular bacterium, transmitted by the tick amblyomma americanum, and is the causative agent of human monocytic ehrlichiosis infections. we previously demonstrated that e. chaffeensis is capable of growing in drosophila s2 cells. therefore, we tested the hypothesis that e. chaffeensis can infect adult drosophila melanogaster. adult drosophila organisms were experimentally challenged with intra-abdominal injections of bacteria. ehrlichia-infected flies s ...200919687202
current management of human granulocytic anaplasmosis, human monocytic ehrlichiosis and ehrlichia ewingii ehrlichiosis.anaplasma phagocytophilum, ehrlichia chaffeensis and ehrlichia ewingii are emerging tick-borne pathogens and are the causative agents of human granulocytic anaplasmosis, human monocytic ehrlichiosis and e. ewingii ehrlichiosis, respectively. collectively, these are referred to as human ehrlichioses. these obligate intracellular bacterial pathogens of the family anaplasmataceae are transmitted by ixodes spp. or amblyomma americanum ticks and infect peripherally circulating leukocytes to cause inf ...200919681699
chemical methods for the synthesis and modification of neoclerodane diterpenes.diterpenes are a structural class of molecules that are derived from four isoprene subunits and are widespread throughout nature. a number of neoclerodane diterpenes have been found to have biological activity but a limited number of chemical investigations have been conducted. recently, the neoclerodane diterpene, salvinorin a (12) has been investigated due to its unique pharmacological profile. this review will discuss the chemical methods used to chemically modify and synthesize 12.200919679471
analysis of complete genome sequence of neorickettsia risticii: causative agent of potomac horse fever.neorickettsia risticii is an obligate intracellular bacterium of the trematodes and mammals. horses develop potomac horse fever (phf) when they ingest aquatic insects containing encysted n. risticii-infected trematodes. the complete genome sequence of n. risticii illinois consists of a single circular chromosome of 879 977 bp and encodes 38 rna species and 898 proteins. although n. risticii has limited ability to synthesize amino acids and lacks many metabolic pathways, it is capable of making m ...200919661282
the united states department of agriculture's northeast area-wide tick control project: summary and conclusions.from 1997 to 2002, the u.s. department of agriculture's northeast area-wide tick control project used acaricide-treated 4-poster deer treatment bait stations in five eastern states to control ticks feeding on white-tailed deer. the objectives of this host-targeted technology were to reduce free-living blacklegged (ixodes scapularis say) and lone star (amblyomma americanum [l.]) tick populations and thereby to reduce the risk of tick-borne disease. during 2002 to 2004, treatments were suspended, ...200919650739
sustained control of gibson island, maryland, populations of ixodes scapularis and amblyomma americanum (acari: ixodidae) by community-administered 4-poster deer self-treatment bait stations.in 1998, twenty-five 4-poster deer treatment bait stations were deployed on gibson island (gi), maryland, as part of the u.s. department of agriculture (usda) northeast area-wide tick control project. treatments concluded in june 2002, having achieved 80% and 99.5% control of blacklegged ticks, ixodes scapularis, and lone star ticks, amblyomma americanum, respectively. no area-wide tick control was attempted again on the island until 2003, when 15 dandux-manufactured 4-posters were purchased by ...200919650736
the impact of 4-poster deer self-treatment devices at three locations in maryland.from 1998-2002 twenty-five deer self-treatment devices (4-posters), using 2% amitraz, were operated at three locations in maryland to determine their effectiveness in controlling blacklegged ticks, ixodes scapularis say, and lone star ticks, amblyomma americanum (l.). each treatment site was approximately 518 ha and paired with a similar site lacking 4-posters. locations varied in deer density, tick abundance, and land use. flagging for host-seeking ticks showed declines in tick populations at a ...200919650735
effectiveness of the 4-poster passive topical treatment device in the control of ixodes scapularis and amblyomma americanum (acari: ixodidae) in new jersey.twenty-five "4-poster" feeders were placed throughout a 5.2 km(2) study area within a secured military facility situated in a hyperendemic area for lyme disease in central monmouth county, new jersey. calculated levels of control, relative to untreated areas, peaked at 82.7%, 77.3%, and 94.2% for of host-seeking ixodes scapularis say larvae, nymphs, and adults, respectively, within 5 years of deployment. control of host-seeking amblyomma americanum (l.) peaked at 99.2%, 89.5%, and 96.9% for larv ...200919650733
community-based prevention of lyme disease and other tick-borne diseases through topical application of acaricide to white-tailed deer: background and rationale.this series of articles describes the first large-scale experiment designed to explore the efficacy of reducing the risk of tick-borne disease in highly endemic communities of the northeastern and mid-atlantic united states through deployment of a self-application device that treats white-tailed deer with acaricide to prevent feeding by adult ixodes scapularis ticks and all stages of amblyomma americanum ticks where both species occur. the results of the multicenter study are reported in the acc ...200919650729
metapopulation structure for perpetuation of francisella tularensis tularensis.outbreaks of type a tularemia due to francisella tularensis tularensis are typically sporadic and unstable, greatly hindering identification of the determinants of perpetuation and human risk. martha's vineyard, massachusetts has experienced an outbreak of type a tularemia which has persisted for 9 years. this unique situation has allowed us to conduct long-term eco-epidemiologic studies there. our hypothesis is that the agent of type a tularemia is perpetuated as a metapopulation, with many sma ...200919627585
silencing of genes involved in anaplasma marginale-tick interactions affects the pathogen developmental cycle in dermacentor variabilis.the cattle pathogen, anaplasma marginale, undergoes a developmental cycle in ticks that begins in gut cells. transmission to cattle occurs from salivary glands during a second tick feeding. at each site of development two forms of a. marginale (reticulated and dense) occur within a parasitophorous vacuole in the host cell cytoplasm. however, the role of tick genes in pathogen development is unknown. four genes, found in previous studies to be differentially expressed in dermacentor variabilis ti ...200919607704
a borreliacidal factor in amblyomma americanum saliva is associated with phospholipase a(2) activity.previous work in our laboratory described the in vitro killing of borrelia burgdorferi when co-cultured with saliva from adult amblyomma americanum. borreliacidal activity was not evident using ixodes scapularis saliva. mixing trypsin with saliva eliminated the borreliacidal activity of a. americanum saliva, while incorporating a trypsin inhibitor restored all borreliacidal activity, indicating this factor was of protein or peptide origin. one dimensional page indicated at least 7 major protein ...200919545533
[stari--a new tick borne spirochetosis].southern tick associated rash illness (stari), also known as masters disease is caused by borrelia lonestari spirochetes and it is transmitted by amblyomma americanum tick. early symptoms of stari are similar to early lyme borreliosis (skin rash resembling erythema migrans). in diagnostic of stari traditional methods are not effective. the decision of antibiotic treatment (similar to lyme borreliosis) still remain based on clinical picture.200919522220
microarray analysis of gene expression changes in feeding female and male lone star ticks, amblyomma americanum (l).a collection of est clones from female tick amblyomma americanum salivary glands was hybridized to rna from different feeding stages of female tick salivary glands and from unfed or feeding adult male ticks. in the female ticks, the expression patterns changed dramatically upon starting feeding, then changed again towards the end of feeding. on beginning feeding, genes possibly involved in survival on the host increased in expression as did many housekeeping genes. as feeding progressed, some of ...200919514082
transovarial transmission of francisella-like endosymbionts and anaplasma phagocytophilum variants in dermacentor albipictus (acari: ixodidae).dermacentor albipictus (packard) is a north american tick that feeds on cervids and livestock. it is a suspected vector of anaplasmosis in cattle, but its microbial flora and vector potential remain underevaluated. we screened d. albipictus ticks collected from minnesota white-tailed deer (odocoileus virginianus) for bacteria of the genera anaplasma, ehrlichia, francisella, and rickettsia using polymerase chain reaction (pcr) gene amplification and sequence analyses. we detected anaplasma phagoc ...200919496436
isolation of entomopathogenic fungi from soils and ixodes scapularis (acari: ixodidae) ticks: prevalence and methods.entomopathogenic fungi are commonly found in forested soils that provide tick habitat, and many species are pathogenic to ixodes scapularis say, the blacklegged tick. as a first step to developing effective biocontrol strategies, the objective of this study was to determine the best methods to isolate entomopathogenic fungal species from field-collected samples of soils and ticks from an eastern deciduous forest where i. scapularis is common. several methods were assessed: (1) soils, leaf litter ...200919496427
prospective health assessment of fort campbell, kentucky patrons bitten by ticks.amblyomma americanum is an aggressive human-biting tick that transmits several known human pathogens and is associated with a lyme disease-like illness of unknown etiology. to determine the frequency, distinguishing clinical characteristics, and etiology ofa. americanum-associated illness and identify associated risk factors, a prospective study of adult tick-bite victims was conducted at fort campbell from 2005-2007. forty-two participants submitted ticks, none of which contained borrelia lones ...200919485114
promoter analysis of macrophage- and tick cell-specific differentially expressed ehrlichia chaffeensis p28-omp genes.ehrlichia chaffeensis is a rickettsial agent responsible for an emerging tick-borne illness, human monocytic ehrlichiosis. recently, we reported that e. chaffeensis protein expression is influenced by macrophage and tick cell environments. we also demonstrated that host response differs considerably for macrophage and tick cell-derived bacteria with delayed clearance of the pathogen originating from tick cells.200919454021
efficacy of eprinomectin and doramectin against amblyomma americanum (acari: ixodidae) on cattle.steers were treated with doramectin or eprinomectin by daily oral capsule for 28 consecutive days. the level of doramectin in the serum of steers treated at 200 microg/kg/d reached a maximum of 104.0 +/- 22.1 ppb at day 21 and declined from 93.3 +/- 20.5 ppb on the final day of treatment to below detectable by day 56. steers treated at 50 microg/kg/d reached a maximum level of doramectin in the serum of 24.7 +/- 1.2 ppb on day 21 and declined from 24.7 +/- 0.6 ppb on the final day of treatment t ...200919449665
a sustained release gel formulation of doramectin for control of lone star ticks (acari: ixodidae) and horn flies (diptera: muscidae) on cattle.a gel formulation formed by incorporating technical doramectin into a 10% hydroxypropyl methylcellulose aqueous solution was used to subcutaneously inject steers at varying dosages. doramectin serum concentration of steers receiving 600 microg (ai)/kg body weight declined from 21.9 ppb at 0.5 wk to below detectable at 8 wk postinjection. the 1,200 microg (ai)/kg injection resulted in serum concentrations of 29.1 ppb at 0.5 wk and declined to 0.5 ppb at 8 wk postinjection. both the 600 and 1,200 ...200919449664
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