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detection of wolbachia in the tick ixodes ricinus is due to the presence of the hymenoptera endoparasitoid ixodiphagus hookeri.the identification of micro-organisms carried by ticks is an important issue for human and animal health. in addition to their role as pathogen vectors, ticks are also the hosts for symbiotic bacteria whose impact on tick biology is poorly known. among these, the bacterium wolbachia pipientis has already been reported associated with ixodes ricinus and other tick species. however, the origins of wolbachia in ticks and their consequences on tick biology (known to be very diverse in invertebrates, ...201222292021
laboratory-infected ehrlichia chaffeensis female adult amblyomma americanum salivary glands reveal differential gene expression.ticks are efficient ectoparasites that are able to steal blood, a rich source of nutrients, from their vertebrate hosts. the nymphal developmental stage of ticks plays an important role for pathogen transmission to human and other animal hosts. in this article, we describe a bloodmeal-based sex differentiation tool to generate adult female ticks infected with ehrlichia chaffeensis to investigate vector-pathogen interactions (functional genomics and gene expression studies). we demonstrate that t ...201222679861
ixodes scapularis (acari: ixodidae) distribution surveys in the chicago metropolitan region.considering recent studies confirming an increased risk of contracting lyme disease near metropolitan chicago, we surveyed a more comprehensive area to assess whether the geographical distribution and establishment of ixodes scapularis (say) populations across northeast illinois are widespread or limited in occurrence. from may through october 2008 and from april through october 2009, 602 i. scapularis ticks of all three life stages (larva, nymph, adult) were collected from sites in cook, dupage ...201222897059
a peculiar cause of anaphylaxis: no more steak? the journey to discovery of a newly recognized allergy to galactose-alpha-1,3-galactose found in mammalian meat.in recent years, a newly recognized allergic disease has been uncovered, and seemingly idiopathic causes of anaphylaxis now have an explanation. individuals bitten by the lone star tick may develop ige antibodies to the carbohydrate galactose-α-1,3-galactose (alpha-gal). upon exposure of sensitized subjects to mammalian meat containing alpha-gal on glycoproteins or glycolipids, delayed anaphylaxis may ensue, often three to six hours after ingestion.1 many of these individuals have negative aller ...201222815061
fusion to snowdrop lectin magnifies the oral activity of insecticidal ω-hexatoxin-hv1a peptide by enabling its delivery to the central nervous system.the spider-venom peptide ω-hexatoxin-hv1a (hv1a) targets insect voltage-gated calcium channels, acting directly at sites within the central nervous system. it is potently insecticidal when injected into a wide variety of insect pests, but it has limited oral toxicity. we examined the ability of snowdrop lectin (gna), which is capable of traversing the insect gut epithelium, to act as a "carrier" in order to enhance the oral activity of hv1a.201222761779
determination of wolbachia diversity in butterflies from western ghats, india, by a multigene approach.members of the genus wolbachia are intracellular bacteria that are widespread in arthropods and establish diverse symbiotic associations with their hosts, ranging from mutualism to parasitism. here we present the first detailed analyses of wolbachia in butterflies from india with screening of 56 species. twenty-nine species (52%) representing five families were positive for wolbachia. this is the first report of wolbachia infection in 27 of the 29 species; the other two were reported previously. ...201222504801
transmission electron microscopy reveals distinct macrophage- and tick cell-specific morphological stages of ehrlichia chaffeensis.ehrlichia chaffeensis is an emerging tick-borne rickettsial pathogen responsible for human monocytic ehrlichiosis. despite the induction of an active host immune response, the pathogen has evolved to persist in its vertebrate and tick hosts. understanding how the organism progresses in tick and vertebrate host cells is critical in identifying effective strategies to block the pathogen transmission. our recent molecular and proteomic studies revealed differences in numerous expressed proteins of ...201222615806
anaplasma phagocytophilum in small mammals and ticks in northeast florida.human anaplasmosis is an emerging tick-borne disease in the united states, but few studies of the causative agent, anaplasma phagocytophilum, have been conducted in southeastern states. the aim of this study was to determine if a. phagocytophilum is present in small mammals and ticks in northeast florida. polymerase chain reaction assays designed to amplify portions of the major surface protein 2 gene (p44), 16s rdna, and groesl operons were used to test rodent blood and tick dna samples for the ...201222548563
galactose-α-1,3-galactose-specific ige is associated with anaphylaxis but not asthma.ige antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose (α-gal) are common in the southeastern united states. these antibodies, which are induced by ectoparasitic ticks, can give rise to positive skin tests or serum assays with cat extract.201222281828
new species of ehrlichia isolated from rhipicephalus (boophilus) microplus shows an ortholog of the e. canis major immunogenic glycoprotein gp36 with a new sequence of tandem repeats.ehrlichia species are the etiological agents of emerging and life-threatening tick-borne human zoonoses that inflict serious and fatal infections in companion animals and livestock. the aim of this paper was to phylogeneticaly characterise a new species of ehrlichia isolated from rhipicephalus (boophilus) microplus from minas gerais, brazil.201223231731
seroprevalence of ehrlichia canis, ehrlichia chaffeensis and ehrlichia ewingii in dogs in north america.this study evaluated the exposure of dogs to three different ehrlichia spp. in the south and central regions of the united states where vector-borne disease prevalence has been previously difficult to ascertain, particularly beyond the metropolitan areas.201222316160
considerations for assessing maximum critical temperatures in small ectothermic animals: insights from leaf-cutting ants.the thermal limits of individual animals were originally proposed as a link between animal physiology and thermal ecology. although this link is valid in theory, the evaluation of physiological tolerances involves some problems that are the focus of this study. one rationale was that heating rates shall influence upper critical limits, so that ecological thermal limits need to consider experimental heating rates. in addition, if thermal limits are not surpassed in experiments, subsequent tests o ...201222384147
cyp52x1, representing new cytochrome p450 subfamily, displays fatty acid hydroxylase activity and contributes to virulence and growth on insect cuticular substrates in entomopathogenic fungus beauveria bassiana.infection of insects by the entomopathogenic fungus beauveria bassiana proceeds via attachment and penetration of the host cuticle. the outermost epicuticular layer or waxy layer of the insect represents a structure rich in lipids including abundant amounts of hydrocarbons and fatty acids. a member of a novel cytochrome p450 subfamily, cyp52x1, implicated in fatty acid assimilation by b. bassiana was characterized. b. bassiana targeted gene knockouts lacking bbcyp52x1 displayed reduced virulence ...201222393051
anaphylactic reactions to oligosaccharides in red meat: a syndrome in evolution.while most allergic responses to food are directed against protein epitopes and occur within 30 minutes of ingesting the allergen, recent studies suggest that delayed reactions may occur, sometimes mediated by ige antibodies directed against carbohydrate moieties. the objective of this review is to summarize the clinical features and management of delayed hypersensitivity reactions to mammalian meat mediated by ige antibodies to galactose-alpha 1,3-galactose (alpha-gal), an oligosaccharide.201222397506
development of a mitochondrial 12s rdna analysis for distinguishing sciuridae species with potential to transmit ehrlichia and borrelia species to feeding amblyomma americanum (acari: ixodidae).unique oligonucleotide probes were synthesized to distinguish among closely related vertebrate mitochondrial rdna sequences present in residual bloodmeals in emergent amblyomma americanum (l.) (acari: ixodidae) nymph life-stage ticks. use of these probes enabled the identification of the eastern gray squirrel as an important bloodmeal source in nymphs harboring ehrlichia and borrelia species. these results were confirmed by identifying these same bacterial genera in eastern gray squirrel tissues ...201222679888
reverse line blot probe design and polymerase chain reaction optimization for bloodmeal analysis of ticks from the eastern united states.determining the host preference of vector ticks is vital to elucidating the eco-epidemiology of the diseases they spread. detachment of ticks from captured hosts can provide evidence of feeding on those host species, but only for those species that are feasible to capture. recently developed, highly sensitive molecular assays show great promise in allowing host selection to be determined from minute traces of host dna that persist in recently molted ticks. using methods developed in europe as a ...201222679879
presence, genetic variability, and potential significance of "candidatus midichloria mitochondrii" in the lone star tick amblyomma americanum.we used next generation sequencing to detect the bacterium "candidatus midichloria mitochondrii" for the first time in lone star ticks (amblyomma americanum) from the eastern united states. 177 individuals and 11 tick pools from seven sites in four states were tested by pyrosequencing with barcoded 16s rrna gene eubacterial primers targeting variable regions 5-3. average infection prevalence was 0.15 across all surveyed populations (range 0-0.29) and only the site with the smallest sample size ( ...201222678102
plane of nutrition by tick-burden interaction in cattle: effect on growth and metabolism.ticks are external parasites, which pose a significant economic burden to domestic animal agriculture. the effects of ticks on grazing animals may be exacerbated during periods of low nutrition, such as those encountered during drought. it is not completely understood how plane of nutrition and tick burden interact to affect metabolism in cattle. the objective of the current research was to examine the plane of nutrition by tick-burden interaction in cattle and determine the effects of this inte ...201222665634
insulin-like growth factor binding protein 7, a member of insulin-like growth factor signal pathway, involved in immune response of small abalone haliotis diversicolor.insulin-like growth factor binding protein 7 (igfbp7), the only member of the igfbp superfamily that binds strongly to insulin, may have different functions from other igfbps. unlike other igfbps, there is no knowledge available on aquatic invertebrate igfbp7. in this study, a molluscan igfbp7 gene, saigfbp7, was cloned for the first time from the small abalone haliotis diversicolor. its full-length cdna sequence is 1812 bp, with a 720 bp open reading frame encoding a protein of 239 aa. the mole ...201222584203
expression and regulation of macrophage migration inhibitory factor (mif) in feeding american dog ticks, dermacentor variabilis.macrophage migration inhibitory factor (mif) is a pro-inflammatory cytokine produced by many mammalian tissues. it is also found in ticks and may function to aid the tick in regulating host responses to tick feeding. our hypothesis is that mif functions in tick blood meal acquisition and pathogen transmission. this study was performed to understand the expression and regulation of mif in the american dog tick, dermacentor variabilis during early stages of blood feeding. we used quantitative reve ...201222476444
the ecology of fear: host foraging behavior varies with the spatio-temporal abundance of a dominant ectoparasite.prey engage in myriad behaviors to avoid predation, and these indirect effects of predators on their prey are often measured by the amount of food abandoned by a forager (the "giving-up density", or gud) in a given habitat. recent evidence suggests that hosts may engage in comparable behaviors to avoid exposure to parasites. we investigated changes in local foraging and regional space use by mammal hosts for the lone star tick (amblyomma americanum), using guds as an indicator of the perceived r ...201222311098
efficacy of plant-derived and synthetic compounds on clothing as repellents against ixodes scapularis and amblyomma americanum (acari: ixodidae).we conducted field trials to compare the relative repellent activity of two natural product compounds (nootkatone and carvacrol) with commercially available plant-derived (ecosmart organic insect repellent) and permethrin-based (repel permanone) repellents against adult ixodes scapularis say and amblyomma americanum (l.) (acari: ixodidae) by using treated coveralls. one day after treatment, nootkatone and carvacrol provided 100% repellency of i. scapularis adults, with nootkatone maintaining com ...201222308777
efficacy of amitraz-impregnated collars on white-tailed deer (artiodactyla: cervidae) in reducing free-living populations of lone star ticks (acari: ixodidae).over a 7 yr period, we monitored the effect of a commercially available, amitraz impregnated anti-tick collar in controlling free-living populations of lone star ticks, amblyomma americanum (l.) when manually fitted around necks of white-tailed deer, odocoileus virginianus (zimmermann). study animals in treatment and control groups were confined in 38.8 ha game-fenced and densely vegetated treatment plots in south texas. tick densities during years 1 and 7 served as untreated pre- and posttreatm ...201223356088
relationship between habitat type, fire frequency, and amblyomma americanum populations in east-central alabama.ticks were collected from 20 sites in the calhoun, cherokee, and cleburne counties in east-central alabama areas to determine the relationship between plant physiognomy, environmental variables, and tick populations. sites investigated included various burning regimes, wildland-urban-interface (wui), a college campus, and an unmanaged area. amblyomma americanum (l.) (acari: ixodidae) dominated the tick population while ixodes scapularis say was not encountered. there were complex differences in ...201223181862
experimental use of two standard tick collection methods to evaluate the relative effectiveness of several plant-derived and synthetic repellents against ixodes scapularis and amblyomma americanum (acari: ixodidae).we used two standard tick collection methods to test the relative effectiveness of two natural product compounds (nootkatone and carvacrol, classified as an eremophilene sesquiterpene and a monoterpene, respectively, that are derived from botanical sources) with commercially-available plant-derived (ecosmart organic insect repellent, comprised of plant essential oils) and permethrin-based (repel permanone) repellents against ixodes scapularis say and amblyomma americanum (l.). cloth drags were e ...201122299371
brown spider (loxosceles genus) venom toxins: tools for biological purposes.venomous animals use their venoms as tools for defense or predation. these venoms are complex mixtures, mainly enriched of proteic toxins or peptides with several, and different, biological activities. in general, spider venom is rich in biologically active molecules that are useful in experimental protocols for pharmacology, biochemistry, cell biology and immunology, as well as putative tools for biotechnology and industries. spider venoms have recently garnered much attention from several rese ...201122069711
food-induced anaphylaxis.food-induced anaphylaxis (fia) is a serious allergic reaction that may cause death rapidly in otherwise healthy individuals. there is no universal agreement on its definition or criteria for diagnosis. hospital admissions for fia have more than doubled in the last decade. food is one of the most common causes of anaphylaxis, with most surveys indicating that food-induced reactions account for 30% to 50% of cases. the most commonly implicated foods are peanut, tree nuts, milk, eggs, sesame seeds, ...201122244239
prostaglandins and their receptors in insect biology.we treat the biological significance of prostaglandins (pgs) and their known receptors in insect biology. pgs and related eicosanoids are oxygenated derivatives of arachidonic acid (aa) and two other c20 polyunsaturated fatty acids. pgs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. the actions of most pgs are mediated by specific receptors. ...201122654840
distribution and infection frequency of 'candidatus rickettsia amblyommii' in maryland populations of the lone star tick (amblyomma americanum) and culture in an anopheles gambiae mosquito cell line.amblyomma americanum (the lone star tick) is a broadly distributed tick that transmits multiple pathogens of humans and domestic animals. 'candidatus rickettsia amblyommii' is a spotted-fever group rickettsial species that is potentially associated with human disease. in 2008 and 2009, we assayed over 500 unfed adult ticks from 19 maryland populations for the presence of 'candidatus r. amblyommii'. infection frequencies ranged from 33% to 100%, with an average infection rate of 60% in 2008 and 6 ...201122309857
implication of haematophagous arthropod salivary proteins in host-vector interactions.the saliva of haematophagous arthropods contains an array of anti-haemostatic, anti-inflammatory and immunomodulatory molecules that contribute to the success of the blood meal. the saliva of haematophagous arthropods is also involved in the transmission and the establishment of pathogens in the host and in allergic responses. this survey provides a comprehensive overview of the pharmacological activity and immunogenic properties of the main salivary proteins characterised in various haematophag ...201121951834
neural control of salivary glands in ixodid ticks.studies of tick salivary glands (sgs) and their components have produced a number of interesting discoveries over the last four decades. however, the precise neural and physiological mechanisms controlling sg secretion remain enigmatic. major studies of sg control have identified and characterized many pharmacological and biological compounds that activate salivary secretion, including dopamine (da), octopamine, γ-aminobutyric acid (gaba), ergot alkaloids, pilocarpine (pc), and their pharmacolog ...201122119563
migratory birds, ticks, and bartonella.bartonella spp. infections are considered to be vector-borne zoonoses; ticks are suspected vectors of bartonellae. migratory birds can disperse ticks infected with zoonotic pathogens such as rickettsia and tick-borne encephalitis virus and possibly also bartonella. thus, in the present study 386 tick specimens collected in spring 2009 from migratory birds on the mediterranean islands capri and antikythera were screened for bartonella spp. rna. one or more ticks were found on 2.7% of the birds. m ...201122957116
a survey on endoparasites and ectoparasites of stray cats from mashhad (iran) and association with risk factors.as there appeared to be no data available on parasite infection of stray cats in the region and considering the potential threat of stray cats for animal and public health, the present study was carried out using biological samples and necropsy finding collected from cats captured in mashhad city in the northeast of iran. from a total 52 stray cats examined, 18 (34.6%) were male and 34 (65.4%) were female. ten species of endoparasites including helminthes and protozoa and two species of ectopara ...201123024505
Southern Tick-Associated Rash Illness (STARI) in the North: STARI following a tick bite in Long Island, New York.The most common clinical manifestation of Lyme disease is the characteristic rash, erythema migrans (EM). In the 1980s EM-like eruptions were reported in Missouri and other southeastern states. The EM-like eruptions, which were of unknown etiology, often followed the bite of the Lone Star tick (Amblyomma americanum) and the rash is called STARI (southern tick-associated rash illness). Although the Lone Star tick is found in the Lyme disease-endemic areas of New England and Mid-Atlantic regions o ...201121940418
elimination of borrelia burgdorferi and anaplasma phagocytophilum in rodent reservoirs and ixodes scapularis ticks using a doxycycline hyclate-laden bait.a field trial was conducted in a lyme disease-endemic area of new jersey to determine the efficacy of a doxycyline hyclate rodent bait to prophylactically protect and cure small-mammal reservoirs and reduce infection rates in questing ixodes scapularis ticks for borrelia burgdorferi and anaplasma phagocytophilum. the doxycycline-laden bait was formulated at a concentration of 500 mg/kg and delivered during the immature tick feeding season in rodent-targeted bait boxes. the percentage of infected ...201122144454
evaluation of glycoproteins purified from adult and larval camel ticks (hyalomma dromedarii) as a candidate vaccine.in order to identify antigens that can help prevent camel tick infestations, three major glycoproteins (glps) about 97, 66 and 40 kda in size were purified from adult and larval egyptian ticks, hyalomma (h.) dromedarii, using a single-step purification method with con-a sepharose. the purified glps were evaluated as vaccines against camel tick infestation in rabbits. the rabbits received three intramuscular inoculations of glps (20 µg/animal) on days 0, 14, and 28. in the immunoblot analysis, se ...201121897098
First transcriptome of the testis-vas deferens-male accessory gland and proteome of the spermatophore from Dermacentor variabilis (Acari: Ixodidae).Ticks are important vectors of numerous human diseases and animal diseases. Feeding stimulates spermatogenesis, mating and insemination of male factors that trigger female reproduction. The physiology of male reproduction and its regulation of female development are essentially a black box. Several transcriptomes have catalogued expression of tick genes in the salivary glands, synganglion and midgut but no comprehensive investigation has addressed male reproduction and mating. Consequently, a ne ...201121949745
high rates of rickettsia parkeri infection in gulf coast ticks (amblyomma maculatum) and identification of "candidatus rickettsia andeanae" from fairfax county, virginia.the gulf coast tick, amblyomma maculatum, is a vector of rickettsia parkeri, a recently identified human pathogen that causes a disease with clinical symptoms that resemble a mild form of rocky mountain spotted fever. because the prevalence of r. parkeri infection in geographically distinct populations of a. maculatum is not fully understood, a. maculatum specimens collected as part of a tick and pathogen surveillance system in fairfax county, virginia, were screened to determine pathogen infect ...201121867421
Infection prevalences of common tick-borne pathogens in adult lone star ticks (Amblyomma americanum) and American dog ticks (Dermacentor variabilis) in Kentucky.Rocky Mountain spotted fever, Lyme disease, and ehrlichiosis are tick-borne diseases that are reported annually in Kentucky. We conducted a survey to describe infection prevalence of tick-borne pathogens in Amblyomma americanum and Dermacentor variabilis ticks collected in Kentucky. During 2007-2008, we collected 287 ticks (179 D. variabilis and 108 A. americanum) from canine, feral hog, horse, raccoon, white-tailed deer, and human hosts in six counties in Kentucky. Ticks were screened for Ricke ...201121976578
evaluation of 4-poster acaricide applicators to manage tick populations associated with disease risk in a tennessee retirement community.in 1993, four residents of a retirement community in middle tennessee were hospitalized with symptoms of ehrlichiosis causing community managers to implement mitigation methods to reduce tick numbers. for the past four years, managers have utilized 4-poster acaricide applicators that aim to reduce disease risk to residents by killing ticks that feed on deer. to determine the efficacy of this technique, we assessed amblyomma americanum abundance in the vicinity of the devices by dragging 400 m ve ...201122129412
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
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 feeding.in 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 missouri.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 ewingii.in 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-1,3-galactose.in 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
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
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
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
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
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
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
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
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
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
Geographical distribution and prevalence of selected Borrelia, Ehrlichia, and Rickettsia infections in Amblyomma americanum (Acari: Ixodidae) in New Jersey.We used published accounts to describe the known statewide distribution of the lone star tick, Amblyomma americanum, in New Jersey and field surveys to characterize the geographical range of A. americanum and selected A. americanum-transmitted pathogens in Monmouth County, the hypothesized northern limit of the species distribution. Ticks were collected using standardized methods from 50 widely dispersed public access areas within 18 municipalities to produce estimates of relative abundance amon ...201122017087
Ehrlichia chaffeensis transcriptome in mammalian and arthropod hosts reveals differential gene expression and post transcriptional regulation.Human monocytotropic ehrlichiosis is an emerging life-threatening zoonosis caused by obligately intracellular bacterium, Ehrlichia chaffeensis. E. chaffeensis is transmitted by the lone star tick, Amblyomma americanum, and replicates in mononuclear phagocytes in mammalian hosts. Differences in the E. chaffeensis transcriptome in mammalian and arthropod hosts are unknown. Thus, we determined host-specific E. chaffeensis gene expression in human monocyte (THP-1) and in Amblyomma and Ixodes tick ce ...201121915290
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
structure of thymidylate kinase from ehrlichia chaffeensis.the enzyme thymidylate kinase phosphorylates the substrate thymidine 5'-phosphate (dtmp) to form thymidine 5'-diphosphate (dtdp), which is further phosphorylated to dttp for incorporation into dna. ehrlichia chaffeensis is the etiologic agent of human monocytotropic erlichiosis (hme), a potentially life-threatening tick-borne infection. hme is endemic in the united states from the southern states up to the eastern seaboard. hme is transmitted to humans via the lone star tick amblyomma americanum ...201121904055
updates on borrelia burgdorferi sensu lato complex with respect to public health.borrelia burgdorferi sensu lato (s.l.) complex is a diverse group of worldwide distributed bacteria that includes 18 named spirochete species and a still not named group proposed as genomospecies 2. descriptions of new species and variants continue to be recognized, so the current number of described species is probably not final. most of known spirochete species are considered to have a limited distribution. eleven species from the b. burgdorferi s.l. complex were identified in and strictly ass ...201121890064
essential oils of cupressus funebris, juniperus communis, and j. chinensis (cupressaceae) as repellents against ticks (acari: ixodidae) and mosquitoes (diptera: culicidae) and as toxicants against mosquitoes.juniperus communis leaf oil, j. chinensis wood oil, and cupressus funebris wood oil (cupressaceae) from china were analyzed by gas chromatography and gas chromatography-mass spectrometry. we identified 104 compounds, representing 66.8-95.5% of the oils. the major components were: α-pinene (27.0%), α-terpinene (14.0%), and linalool (10.9%) for j. communis; cuparene (11.3%) and δ-cadinene (7.8%) for j. chinensis; and α-cedrene (16.9%), cedrol (7.6%), and β-cedrene (5.7%) for c. funebris. the essen ...201122129397
tick cell lines for study of crimean-congo hemorrhagic fever virus and other arboviruses.abstract continuous cell lines derived from many of the vectors of tick-borne arboviruses of medical and veterinary importance are now available. their role as tools in arbovirus research to date is reviewed and their potential application in studies of tick cell responses to virus infection is explored, by comparison with recent progress in understanding mosquito immunity to arbovirus infection. a preliminary study of propagation of the human pathogen crimean-congo hemorrhagic fever virus (cc ...201121955214
conjunctival attachment of a tick: clinicopathologic report of a case.attachment by ticks to ocular surfaces is uncommon, but has been reported. the objective of this article is to describe a case of conjunctival tick attachment and a method for removal by conjunctival excision. a 39-year-old man presented to the emergency department with a complaint of foreign-body sensation in his right eye. he was found to have a live tick embedded in his conjunctiva. the tick was removed en bloc with surrounding conjunctiva by an ophthalmologist. the arthropod was identified a ...201118514466
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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