Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| experimental transmission of a granulocytic form of the tribe ehrlichieae by dermacentor variabilis and amblyomma americanum to dogs. | transstadial transmission of granulocytic ehrlichieae in dogs was attempted using ticks, amblyomma americanum and dermacentor variabilis. ticks were exposed by feeding as nymphs on acutely infected pups; adult ticks then fed to repletion on susceptible adult dogs that were monitored daily for signs of infection. evidence of transmission was not observed in control dogs or in those exposed to d variabilis. in contrast, dogs exposed to a americanum developed serologic or clinical evidence of infec ... | 1990 | 2368951 |
| rickettsia in texas. | since the first reported case in 1941, rocky mountain spotted fever in humans has been reported from many areas of texas, with two major foci, one located in the north-central region and the other in the eastern region of the state. during the period 1979-1988, 421 cases of rmsf were reported, reaching 108 cases in 1983 and declining in subsequent years. statewide surveillance programs to detect spotted fever group rickettsiae in tick populations were initiated in 1976. in recent years, the sfg ... | 1990 | 2378448 |
| ectoparasitic and phoretic arthropods of virginia opossums (didelphis virginiana) in central tennessee. | thirteen species of ectoparasitic (12) or phoretic (1) arthropods were collected from 26 adult virginia opossums, didelphis virginiana, live-trapped from april through september 1987 in davidson county, tennessee. the cat flea ctenocephalides felis and the american dog tick dermacentor variabilis were the predominant species with respect to mean intensity and prevalence. the macronyssid mite ornithonyssus wernecki and the atopomelid mite didelphilichus serrifer, both specific parasites of this h ... | 1990 | 2380870 |
| effects of sequential infestations of dermacentor albipictus and amblyomma americanum (acari: ixodidae) on overwintering beef cows in west-central texas. | infestations of winter ticks, dermacentor albipictus (packard), observed on mature black angus cows, reached peak levels in january and diminished through march. infestations of adult lone star ticks, amblyomma americanum (l.), began in mid-january and increased through may. cows receiving ectrin, taktic, or deltox treatments on 13 december and 21 february experienced significantly less weight loss and entered the subsequent breeding season with higher average body weight than untreated cows. in ... | 1990 | 2388237 |
| intrinsic competence of three ixodid ticks (acari) as vectors of the lyme disease spirochete. | we compared the intrinsic vector competence of ixodes dammini spielman et al., dermacentor variabilis (say), and amblyomma americanum (l.) for the lyme disease spirochete (borrelia burgdorferi johnson et al.) on prudence island, rhode island, a lyme disease-endemic site where all three ticks occur together. natural and experimental spirochete infection rates were determined in those ticks and their degree of contact with white-footed mice (peromyscus leucopus), the principal reservoir host, was ... | 1990 | 2388239 |
| putative new expression of genes in ixodid tick salivary gland development during feeding. | poly(a+) mrna-enriched fractions from salivary glands of partially fed amblyomma americanum female ticks were translated in vitro with a rabbit reticulocyte translation system. translated proteins were labeled with [35s]methionine, separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, and identified by autoradiography. thirty major identifiable polypeptides with molecular weights ranging from 14 to 136 kda were synthesized from mrna isolated from salivary glands of ticks weighi ... | 1991 | 1710268 |
| tick infestations of white-tailed deer in alabama. | four species of ticks were collected from 537 white-tailed deer (odocoileus virginianus), examined during the hunting seasons (november to january) of 1988-89 and 1989-90 at selected locations in alabama (usa). ixodes scapularis was the most common tick recovered (2,060 specimens) and infested 54% of the deer. dermacentor albipictus was the second most frequent tick (1,253 specimens) and infested 15% of the deer. amblyomma americanum was the third most frequent tick (315 specimens) and infested ... | 1991 | 1758026 |
| rectal infusion and aspiration of material through the guts of ixodid ticks (acari: ixodidae). | a technique for inoculating and removing substances via the anus of vector ticks was devised to define features of vector competence precisely. calibrated inocula (greater than 5 nanoliter) containing aqueous dye and polystyrene beads as well as infectious agents were infused into the rectal sacs of ticks using glass microcapillary pipettes placed within the expanded anal orifice. the guts of preadult and adult ticks, ixodes dammini spielman, clifford, piesman & corwin, dermacentor variabilis (s ... | 1991 | 1770516 |
| role of genital sex pheromones in amblyomma americanum and a. maculatum (acari: ixodidae). | amblyomma americanum and a. maculatum were studied to determine if genital sex pheromones were present, as reported in dermacentor species. chemical analysis of methanol extracts of the anterior reproductive tracts (source of the genital sex pheromone) of a. americanum and a. maculatum confirmed the presence of the same fatty acids that act as components of the genital sex pheromone in dermacentor variabilis and d. andersoni. in both amblyomma species, removal of the anterior reproductive-tract ... | 1991 | 1860418 |
| effect of ivermectin on the volume of blood ingested by two species of ticks (acari: ixodidae) feeding on cattle. | females of the lone star tick, amblyomma americanum (l.), and the american dog tick, dermacentor variabilis (say), were fed on ivermectin (ivomec)-treated and untreated bovines to determine the effect of the acaricide on volume of blood ingested and to compare the weight differences between the treatment and control groups at various time intervals after attachment. adult females from each genus were collected from bos tarus hosts and subjected to hematin assays on three collection dates to esti ... | 1991 | 1875376 |
| manifestations of immunity in sheep repeatedly infested with amblyomma americanum ticks. | three sheep were infested 4 times with 100 amblyomma americanum tick pairs and kept indoors until the natural termination of the infestations. characteristics of the tick populations that show efficiency of feeding, fertility, and offspring development, and elisa antibodies to tick salivary gland extracts were studied at each infestation. on average, female ticks fed on tick-naive sheep detached at 12.1 +/- 0.2 (mean +/- standard error) days, weighed 492 +/- 16.8 mg, engorged 40.7 mg per day, an ... | 1991 | 1919917 |
| antigens of amblyomma americanum ticks recognized by repeatedly infested sheep. | sera were taken from 3 sheep that had been infested 5 times with amblyomma americanum and that exhibited manifestations of humoral depression to homologous antigens and anti-tick resistance. proteins extracted from the intestine or salivary glands of unfed ticks or salivary glands from partially (3-day) fed ticks were analyzed by polyacrylamide gel electrophoresis (page) and sodium dodecyl sulfate-page. antigens recognized by the sheep in the same materials before and after each infestation were ... | 1991 | 1919918 |
| selective breeding for photoperiodically induced developmental diapause in laboratory strains of amblyomma americanum (acari: ixodidae). | offspring of amblyomma americanum (l.) reared for four generations in a 12:12 (l:d) photoperiod in the laboratory were held in 10:14 (l:d) conditions and bred to select for developmental diapause (dia) or nondiapause (non) characteristics for two additional generations. sequential generations of fed dia nymphs had mean molting times (days from detachment to ecdysis) that were 8.0% (dia1) and 35.7% (dia2) greater than parental ticks, and maximal development time was extended by 20% in dia2 ticks ... | 1991 | 1941917 |
| mechanisms of host-tick contact with special reference to amblyomma americanum (acari: ixodidae) in beef cattle forage areas. | at least five groups of parameters regulate contact between ticks and host animals. group 1 (seasonal effects) and group 2 (daily effects) comprise abiotic parameters and include daylength, temperature, relative humidity, and interactions thereof. groups 3, 4, and 5 consist of biotic parameters. these pertain to biological processes in ticks (group 3), such as hunger responses and spatial patterns in aphagous tick populations; biological processes in host animals (group 4), such as patterns of h ... | 1991 | 1941920 |
| etiologic agent of lyme disease, borrelia burgdorferi, detected in ticks (acari: ixodidae) collected at a focus in alabama. | the study was conducted at sites of known transmission of borrelia burgdorferi in east central alabama. the objectives were to determine species of ticks present at these sites, their host associations, and species of ticks and small mammals naturally infected with b. burgdorferi. a total of 451 hosts were examined for ticks, including cotton mice, peromyscus gossypinus (le conte); cotton rats, sigmodon hispidus say & ord; southern short-tailed shrews, blarina carolinensis (bachman); house mice, ... | 1991 | 1941933 |
| borrelia burgdorferi in ticks (acari: ixodidae) from coastal virginia. | ixodid ticks removed from hosts and from vegetation during march-november 1987 at sites in coastal virginia and north carolina were examined for borrelia burgdorferi. b. burgdorferi was evident in nine (22%) ixodes cookei packard removed from rice rats (oryzomys palustris), a white-footed mouse (peromyscus leucopus), and raccoons (procyon lotor); four (6%) amblyomma americanum (l.) removed from raccoons; and two (3%) dermacentor variabilis (say) removed from a raccoon and a rice rat. b. burgdorf ... | 1991 | 1941936 |
| horizontal movement of adult ixodes dammini (acari: ixodidae) attracted to co2-baited traps. | the ability of male and female deer ticks, ixodes dammini spielman, clifford, piesman, & corwin, to move horizontally was evaluated by performing a mark-recapture study. in each of two experiments, 120 ticks were marked with fluorescent powder and released at predetermined distances from a co2-baited trap. the mean recruitment distance was 1.8 m after 6 d of trap operation. this distance is appreciably lower than those calculated from previous studies of several other species of ixodid ticks, in ... | 1991 | 1941943 |
| ehrlichiosis in children. | tick-borne rickettsiae of the genus ehrlichia have recently been recognized as a cause of human illness in the united states. in the years 1986-1988, 10 cases of ehrlichiosis were diagnosed in children in oklahoma. fever and headache were universal: myalgias, nausea, vomiting, and anorexia were also common. rash was observed in six patients but was a prominent finding in only one. leukopenia, lymphopenia, and thrombocytopenia were common laboratory abnormalities. six patients were treated with t ... | 1991 | 1987531 |
| tick information sheet. the lone star tick. amblyomma americanum. | 1991 | 2014616 | |
| increased population densities of amblyomma americanum (acari: ixodidae) on long island, new york. | lone star ticks, amblyomma americanum comprised a significantly greater proportion of total ticks flagged on eastern long island and fire island, new york, in 1986 and 1990 than in samples reported by other authors from the 1940s (when a. americanum was not collected by flagging or from hosts) and the 1970s. therefore, population densities of a. americanum apparently have increased in recent years on southeastern long island, where this species now is distributed widely. | 1991 | 2040963 |
| further investigations on the action of ecdysteroids on the salivary glands of the female tick amblyomma americanum. | two phytecdysteroids (abutasterone, makisterone a) and five synthetic ecdysteroid analogues, all at 1 microgram/ml, were tested on salivary glands from the female tick, amblyomma americanum l. (acari:ixodidae), held in organ culture for four days. all of these substances caused a significant reduction in fluid secretory competence of salivary glands in vitro. this constitutes further evidence that the structural requirements for causing salivary-gland degeneration in ticks are similar to those g ... | 1991 | 2044433 |
| hyperosmotic oral fluid secretion during active water vapour absorption and during desiccation-induced storage-excretion by the unfed female tick amblyomma americanum. | 1991 | 2061709 | |
| isolation of borrelia burgdorferi from arthropods collected in texas. | the texas department of health laboratory cultured arthropods from november 1988 through december 1989 in an attempt to isolate borrelia burgdorferi, the etiologic agent of lyme disease. spirochetes were isolated from eight of 1,093 pools of arthropods cultured. the spirochetal isolates were from several tick and one flea species, including amblyomma americanum, a. maculatum, ixodes scapularis, and ctenocephalides felis. these 8 isolates reacted specifically when treated with monoclonal antibodi ... | 1991 | 2063950 |
| synganglial morphology and neurosecretory centers of adult amblyomma americanum (l.) (acari: ixodidae). | lone star ticks, amblyomma americanum (l.), were processed by standard histological means for paraffin embedding, sectioning, and staining by the paraldehyde-fuchsin technique. the synganglion is highly condensed around the esophagus and possesses paired optic, cheliceral, palpal, pedal i-iv nerves, and opisthosomal nerves and a single unpaired esophageal nerve. although optic nerves were observed leading from the eyes to the protocerebrum, distinct optic ganglia were not seen in any of the prep ... | 1992 | 1460618 |
| parasites of cottontail rabbits of southern illinois. | fifteen species of parasites including haemaphysalis leporispalustris, ixodes dentatus, amblyomma americanum, cediopsylla simplex, odontopsyllus multispinosus, cuterebra sp., obeliscoides cuniculi, trichostrongylus calcaratus, trichostrongylus affinis, longistriata noviberiae, dermatoxys veligera, trichuris sp., mosgovoyia sp., taenia pisiformis, and hasstilesia tricolor as well as coccidia oocysts were collected from 96 cottontail rabbits (sylvilagus floridanus) confined to a pen in southern il ... | 1992 | 1491303 |
| tick (acari: ixodidae) attachment cement and salivary gland cells contain similar immunoreactive polypeptides. | a specific antiserum (12c) raised to a 90-kda immunogenic component of salivary glands of the tick rhipicephalus appendiculatus recognized similar 90-kda polypeptides from salivary glands of the american dog tick, dermacentor variabilis, and the lone star tick, amblyomma americanum, as well as 70-kda polypeptides in the cement of d. variabilis, a. americanum, and r. sanguineus (brown dog tick). the reduction in size of the polypeptide for these ticks suggests that it is modified in some way duri ... | 1992 | 1495047 |
| tick sweep: modification of the tick drag-flag method for sampling nymphs of the deer tick (acari: ixodidae). | we describe a version of the standard tick drag-flag modified for use in close-growing and tangled vegetation, as well as under ornamental shrubbery and fallen branches. two major features of the sweep are: (1) it allows the user to remain upright with the flag parallel to the ground, thus sampling effectively beneath low and fallen branches and around shrubs, as well as capturing host-seeking ticks in advance of the operator; and (2) the use of a flannel rubberized-laminate fabric (crib sheet) ... | 1992 | 1495058 |
| field evaluation of two formulations of cyfluthrin for control of ixodes dammini and amblyomma americanum (acari: ixodidae). | liquid or granular cyfluthrin was applied in the spring and fall to different test plots at a rate of 0.41 (ai) kg/ha to control ixodes dammini spielman, clifford, piesman & corwin and amblyomma americanum (l.). spring application of liquid cyfluthrin showed the most significant decreases of both species. i. dammini nymphs were reduced 97% at 10 d, 100% at 2 mo, and 100% at 1 yr; and a. americanum adults and nymphs were reduced 91-93% at 10 d and 100% at 2 mo posttreatment. granular cyfluthrin a ... | 1992 | 1495073 |
| attempted transmission of borrelia burgdorferi (spirochaetales: spirochaetaceae) (jdi strain) by ixodes scapularis (acari: ixodidae), dermacentor variabilis, and amblyomma americanum. | laboratory-reared ixodes scapularis say, amblyomma americanum (l.), and dermacentor variabilis (say) were fed on new zealand white rabbits experimentally infected with borrelia burgdorferi (jdi strain). at repletion, spirochetes could be detected by dark-field microscopy only in i. scapularis. acquisition rates were 18 and 21%. when previously exposed nymphs of each species were fed on susceptible rabbits, i. scapularis was the only tick of the three species that transmitted b. burgdorferi. when ... | 1992 | 1495078 |
| borrelia sp. in ticks recovered from white-tailed deer in alabama. | six hundred sixty-five hunter-killed white-tailed deer (odocoileus virginianus) from 18 counties in alabama (usa) were examined for ticks. most of the collections were made at state-operated wildlife management areas. four species of ticks (n = 4,527) were recovered: the lone star tick amblyomma americanum (n = 482); the gulf coast tick a. maculatum (n = 11); the winter tick dermacentor albipictus (n = 1,242); and the black-legged tick ixodes scapularis (n = 2,792). fifty-six percent of the tick ... | 1992 | 1512879 |
| monthly incidence of theileria cervi and seroconversion to babesia odocoilei in white-tailed deer (odocoileus virginianus) in texas. | monthly monitoring of fawns collected from an area in texas endemic for theileria cervi and babesia odocoilei showed that transmission of t. cervi occurred during july and august, a time period consistent with the occurrence of amblyomma americanum. seroconversion to b. odocoilei occurred during october to december and possibly continued through january and february. the time of seroconversion was more suggestive of transmission of b. odocoilei by ixodes scapularis than by amblyomma americanum. | 1992 | 1512881 |
| ectoparasites of the blackbuck antelope (antilope cervicapra). | fifty-two free-ranging blackbuck antelope (antilope cervicapra) from texas were examined for ectoparasites. two species of sucking lice (anoplura), one species of chewing louse (mallophaga), one species of louse fly (diptera), and three species of ticks (acari) were found. this is the first report of the anoplurans linognathus cervicaprae and l. pithodes from the western hemisphere. the southern deer ked (lipoptena mazamae), the winter tick (dermacentor albipictus), and the rabbit tick (haemaphy ... | 1992 | 1512888 |
| oral secretion elicited by effectors of signal transduction pathways in the salivary glands of amblyomma americanum (acari: ixodidae). | the abilities of various effectors of signal pathways in tick salivary glands to stimulate oral secretions in partially fed amblyomma americanum (l.) female ticks were compared. pilocarpine stimulated secretion the most rapidly following tick stimulation, but its effectiveness declined with time and subsequent injections. secretion rates induced by dopamine and theophylline increased with time of collection and additional injections and were as effective as pilocarpine after 60 min. activators o ... | 1992 | 1552527 |
| distribution, density, and lyme disease spirochete infection in ixodes dammini (acari: ixodidae) on white-tailed deer in maryland. | a statewide survey of ticks parasitizing white-tailed deer was carried out in maryland during november 1989 to assess the status of the deer tick, ixodes dammini spielman, clifford, piesman & corwin, the major vector of lyme disease in the northeastern united states. ticks were collected from deer carcasses brought in by hunters at 23 check stations (one per county). a total of 3,437 i. dammini were collected from 538 of 1,281 deer (42%), together with 2,013 dermacentor albipictus (packard) and ... | 1992 | 1552529 |
| amblyomma americanum (l.): protein kinase c-independent fluid secretion by isolated salivary glands. | protein kinase c activity was partially purified from tick salivary glands by fast protein liquid chromatography anion-exchange chromatography. enzyme activity was stimulated by ca2+, phosphatidylserine, and diacylglycerol with the highest activity observed in the presence of all three modulators. enzyme activity was inhibited by a synthetic pseudosubstrate peptide with an amino acid sequence resembling the protein kinase c substrate phosphorylation site. the protein kinase c activator, 1-oleoyl ... | 1992 | 1582485 |
| quantitative evaluation of sampling methods for ixodes dammini and amblyomma americanum (acari: ixodidae). | three tick-sampling methods (dry ice-baited tick traps, cloth drags, and ambulatory human host) were evaluated to determine which technique yielded the greatest capture of host-seeking stages of ixodes dammini spielman, clifford, piesman & corwin and amblyomma americanum (l.). the most reliable method, catching more stages and significantly more numbers of i. dammini and a. americanum; was dry ice-baited tick traps. there were no significant differences between the drag and human-host methods fo ... | 1992 | 1625293 |
| inability of ixodes cookei and amblyomma americanum nymphs (acari: ixodidae) to transmit borrelia burgdorferi. | the vector competency of ixodes cookei packard and amblyomma americanum (l.) for borrelia burgdorferi was studied using syrian hamsters. ixodes dammini spielman, clifford, piesman & corwin were used as controls. darkfield and immunofluorescent examinations of midgut diverticula revealed b. burgdorferi spirochetes in 32 of 36 (88.9%) i. dammini larvae, 5 of 36 (13.9%) i. cookei larvae, and 7 of 36 (19.4%) a. americanum larvae within 48 h after feeding on infected syrian hamsters. b. burgdorferi w ... | 1992 | 1625302 |
| amblyomma americanum: characterization of salivary prostaglandins e2 and f2 alpha by rp-hplc/bioassay and gas chromatography-mass spectrometry. | secretagogue-induced saliva of the tick, amblyomma americanum (l.) was fractionated by reversed-phase-high-performance liquid chromatography (rp-hplc) and bioassayed in smooth muscle preparations. material with retention times of authentic prostaglandin e2 (pge2) and prostaglandin f2 alpha (pgf2 alpha) were found to cause contraction of preparations of rat colon and rat stomach strips. gas chromatography-mass spectra of selected ions of both hplc-purified fractions confirmed the existence of pge ... | 1992 | 1730268 |
| isolation and transmission of the lyme disease spirochete from the southeastern united states. | the isolation of the lyme disease spirochete (borrelia burgdorferi) from the southeastern united states is reported. three isolates, two from cotton mice (peromyscus gossypinus) and one from the black-legged tick (ixodes scapularis), were recovered from sapelo island, georgia, in july and september 1991. the spirochetes were characterized by indirect fluorescent antibody assay using a battery of five monoclonal antibodies, by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (sds/page) o ... | 1993 | 8346258 |
| amblyomma americanum: a potential vector of human ehrlichiosis. | polymerase chain reaction primers specific for ehrlichia chaffeensis were used to amplify dna from extracts of pooled ticks. amplification was performed on extracts from 140 pools (1,579 total ticks) consisting of three tick genera collected from five states. the characteristic 389-basepair product was observed after amplification of extracts from seven different pools of adult amblyomma americanum (117 pools, 1,462 ticks), but not from pools of nymphs. no specific product was observed after amp ... | 1993 | 8357086 |
| implications of selection and hybridization studies on the mode of inheritance of photoperiodically induced developmental diapause in laboratory strains of the lone star tick (acari: ixodidae). | selection of lone star ticks, amblyomma americanum (l.), that were reared in the laboratory under short-day photoperiods of 10:14 (l:d) h resulted in third generation (f3) diapause versus f3 nondiapause strain replete nymphs having significantly different mean molting times (days from detachment to ecdysis) of 100.9 versus 54.7 d, respectively; whereas, the f7 unselected laboratory control strain had an even smaller, significantly different mean molting time of 49.5 d. two hybrid crosses of f2 n ... | 1993 | 8433316 |
| analysis of lipids in the salivary glands of amblyomma americanum (l.): detection of a high level of arachidonic acid. | analysis of lipids in salivary glands of the lone star tick, amblyomma americanum, demonstrated that arachidonic acid (20:4, n-6) comprises 8% of all fatty acids identified by gas chromatography. the occurrence of arachidonic acid and other c20 polyunsaturated fatty acids in tick salivary glands was confirmed by gas chromatography-mass spectrometry. arachidonate is located entirely in the phospholipid fraction and is associated exclusively with phosphatidylcholine (pc) and phosphatidylethanolami ... | 1993 | 8324244 |
| computer-controlled olfactometer system for studying behavioral responses of ticks to carbon dioxide. | an olfactometer system that consisted of a laptop computer, a carbon dioxide analyzer, and an apparatus to control gas flows was designed to study ixodid tick behavioral responses to varying carbon dioxide (co2) concentrations. the system provided a method to regulate and measure stimulatory co2 concentrations (1-99 ppm) above ambient co2 background levels. adult amblyomma americanum (l.) and dermacentor variabilis (say) demonstrated behavioral responses to co2 concentrations as low as 9 ppm abo ... | 1993 | 8510116 |
| new version of lstsim for computer simulation of amblyomma americanum (acari: ixodidae) population dynamics. | a previous version of lone star tick simulation model (lstsim) for a wildlife ecosystem was revised and expanded to include a beef cattle forage area and improved handling of tick-host-habitat interactions. relationships between environmental and biological variables were also refined in the new version. general validity of the revised model was established by comparing simulated and observed host-seeking populations of amblyomma americanum (l.) at five geographic locations, three in oklahoma an ... | 1993 | 8254630 |
| ticks (acari: ixodidae) infesting medium-sized wild mammals in southwestern tennessee. | seven species of ixodid ticks (n = 2,661) were found on medium-sized wild mammals (n = 295) during a 13-mo study in shelby county, tennessee. the seven tick species collected were dermacentor variabilis (say), amblyomma americanum (l.), rhipicephalus sanguineus (latreille), ixodes texanus (banks), i. cookei (packard), i. scapularis (say), and haemaphysalis leporispalustris (packard). the raccoon had the greatest tick species diversity in all of the aforementioned ticks except h. leporispalustris ... | 1993 | 8254637 |
| changes in lipids of the salivary glands of the lone star tick, amblyomma americanum, during feeding. | the lipid composition of salivary glands from male and female lone star ticks, amblyomma americanum, was investigated at progressive stages of tick feeding. the amounts of fatty acids from both phospholipid and neutral lipid fractions increased dramatically during the initial stage of feeding and peaked in partially fed females weighing 100-250 mg. percentage compositions of myristic (14:0) and palmitic acid (16:0) decreased, but stearic (18:0), oleic (18:1), linoleic (18:2), and arachidonic aci ... | 1993 | 8277375 |
| evidence supporting the presence of borrelia burgdorferi in missouri. | although lyme disease is commonly seen in the southcentral united states, the epidemiology of the disease is poorly defined there. the purpose of this study was to document the presence of borrelia burgdorferi in ticks collected in southeastern missouri and around the city of st. louis. spirochetes were detected and identified as b. burgdorferi by immunofluorescent antibody (ifa) tests using the monoclonal antibody h5332 in 1.9% of amblyomma americanum and 2.0% of dermacentor variabilis ticks co ... | 1994 | 7943575 |
| seasonal and annual abundance of amblyomma americanum (acari: ixodidae) in central georgia. | seasonal and annual changes in the abundance of amblyomma americanum (l.) larvae, nymphs, and adults were monitored over a 5-yr period in the piedmont physiographic region of georgia. tick abundance was monitored with cloth drags (all life stages) and co2-baited cloth panels (nymphs and adults) monthly during march through september from 1987 through 1991. larvae appeared in substantial numbers in july and were most numerous in august and september. small numbers of unfed larvae apparently overw ... | 1994 | 8158632 |
| influence of annual and biennial prescribed burning during march on the abundance of amblyomma americanum (acari: ixodidae) in central georgia. | a 5-yr study to evaluate the influence of annual and biennial prescribed burning in march on the abundance of amblyomma americanum (l.) was conducted on oconee wildlife management area in the piedmont physiographic region of georgia. tick abundance on plots embedded in larger burned and unburned areas were monitored with cloth drags and co2-baited cloth panels monthly during march through september from 1987 through 1991. annual and biennial prescribed burning from 1988 to 1991 significantly red ... | 1994 | 8158633 |
| integrated management strategies for amblyomma americanum (acari: ixodidae) on pastured beef cattle. | data on tick control and knowledge of the damage caused to beef cattle by tick feeding were incorporated into a computerized dynamic life table model (lstsim) for amblyomma americanum (l.). simulations were made to determine economically feasible, 5-yr integrated pest management (ipm) strategies for a. americanum in forage areas utilized by bos taurus, bos indicus, and crossbred cattle (b. taurus x b. indicus). the effects of host resistance, pasture rotation, habitat conversion, topical acarici ... | 1994 | 7932604 |
| ectoparasites of opossums and raccoons in southeastern georgia. | twelve species of ectoparasites (four fleas, three ticks, three chiggers, one macronyssid mite, and one atopomelid mite) were recovered from 42 opossums, didelphis virginiana kerr, live-trapped from september 1992 through april 1994 in southeastern georgia. the fleas, ctenocephalides felis (bouché) (prevalence = 19%) and polygenis gwyni (c. fox) (36%); the ticks, dermacentor variabilis (say) (40%) and ixodes scapularis say (19%); and the macronyssid mite, ornithonyssus wernecki (fonseca) (21%), ... | 1994 | 7815408 |
| origin, accumulation and mobilization of salivary prostaglandin precursors in the lone star tick. | 1994 | 7958372 | |
| ticks (acari: ixodidae) collected from small and medium-sized kansas mammals. | seven species of hard-bodied ticks were collected from 20 species of small and medium-sized mammals in kansas; amblyomma americanum l., dermacentor variabilis (say), haemaphysalis leporispalustris (packard), ixodes cookei packard, i. kingi bishopp, i. sculptus neumann, and i. texanus banks. dermacentor variabilis was found statewide, a. americanum only in the eastern one-third of the state, and the ixodes spp. and h. leporispalustris were widely scattered. the most common tick found was d. varia ... | 1994 | 8057327 |
| serologic diagnosis of human monocytic ehrlichiosis by immunoblot analysis. | human monocytic ehrlichiosis is caused by ehrlichia chaffeensis, an intracellular bacterium probably transmitted by the tick amblyomma americanum in the united states. despite its lack of specificity in discriminating among infections by closely related ehrlichia spp., immunofluorescence assay (ifa) is the most frequently used serological diagnostic method. to improve the specificity of the serological diagnosis, we compared antigenic profile of e. canis and e. chaffeensis antigen with homologou ... | 1994 | 8556515 |
| distribution of arachidonic acid among phospholipid subclasses of lone star tick salivary glands. | the subclass composition of choline- and ethanolamine-containing phospholipids was determined by analysis of acyl-linked fatty acids released by base hydrolysis of diradylglycerobenzoates formed from lone star tick salivary gland diacyl, alkylacyl and alkenylacyl phospholipids. the diacyl subclass comprises 87% of all choline-containing phospholipids, while th alkylacyl subclass comprises c. 9% and the alkenylacyl subclass c. 4%. the diacyl subclass comprises 72-77% of ethanolamine-containing ph ... | 1994 | 8069331 |
| genome size and organization in the ixodid tick amblyomma americanum (l.). | we used dna reassociation kinetics to determine genome size and organization in the ixodid tick amblyomma americanum. we calculated the genome size of a. americanum to be approximately 1.08 pg or 1.04 x 10(9) base pairs and to consist of 35.8% unique dna, 4.2% foldback sequences, 17.9% highly repetitive sequences, and 42.1% moderately repetitive sequences. comparison of the reassociation kinetics of long and short fragments revealed repetitive sequences to be distributed in a pattern of long per ... | 1994 | 8069417 |
| prevalence of borrelia (spirochaetaceae) spirochetes in texas ticks. | between 1990 and 1992, ticks from eight texas parks were collected and analyzed to determine the prevalence of spirochete-infected ticks. borrelia spirochetes were detected in 1.03% of 5,141 amblyomma americanum (l.) adults examined, a species texas residents often encounter. no spirochetes were observed in the other tick species tested. | 1994 | 8189421 |
| hemocytic rickettsia-like organisms in ticks: serologic reactivity with antisera to ehrlichiae and detection of dna of agent of human granulocytic ehrlichiosis by pcr. | ixodid ticks were collected from connecticut, massachusetts, missouri, pennsylvania, rhode island, and british columbia (canada) during 1991 to 1994 to determine the prevalence of infection with hemocytic (blood cell), rickettsia-like organisms. hemolymph obtained from these ticks was analyzed by direct and indirect fluorescent antibody (fa) staining methods with dog, horse, or human sera containing antibodies to ehrlichia canis, ehrlichia equi, or rickettsia rickettsii. of the 693 nymphal and a ... | 1995 | 8567911 |
| epidemiologic and diagnostic studies of patients with suspected early lyme disease, missouri, 1990-1993. | a retrospective case-control study investigated 45 missouri outpatients with annular rashes meeting a surveillance case definition for erythema migrans and with onset in 1990-1991. risk factors included being male, living near a body of water, and hunting. twenty patients (44%) associated their rash with the bite of a tick; of these, 5 described an adult amblyomma americanum. a typical rash was described as expanding over time and measuring 8 cm in diameter at 4 days after onset. mild constituti ... | 1995 | 7622891 |
| biosynthesis of salivary prostaglandins in the lone star tick, amblyomma americanum. | dopamine-induced saliva from ticks fed [3h]arachidonic acid contained the radiolabelled prostaglandins e2, f2 alpha, d2, and b2, the latter probably derived from pge2 owing to the alkalinity of tick saliva. prostaglandin synthetase (pgs) activity in the salivary gland homogenate from the lone star tick, amblyomma americanum, could not be detected by standard radiometric methodologies successfully employed for tissues from many animal species, including numerous arthropods. modifications to the a ... | 1995 | 7627205 |
| evaluation of ixodes scapularis, amblyomma americanum, and dermacentor variabilis (acari: ixodidae) from georgia as vectors of a florida strain of the lyme disease spirochete, borrelia burgdorferi. | the ability of three common tick species from georgia to maintain and transmit the causative agent of lyme disease, borrelia burgdorferi, was compared under laboratory conditions. a b. burgdorferi cotton rat isolate (mi-6) from florida was selected as a strain from the south, and the sh2-82 isolate from new york was used as a positive control. amblyomma americanum (l.) and dermacentor variabilis (say) did not transmit the mi-6 isolate from inoculated hamsters to naive laboratory mice, and nympha ... | 1995 | 7650697 |
| borrelia burgdorferi in eastern virginia: comparison between a coastal and inland locality. | in virginia, borrelia burgdorferi was more prevalent in a site along the atlantic ocean, near maryland, than in an inland site near williamsburg and yorktown. at the coastal site on assateague island, b. burgdorferi was isolated from 4.2% of 475 animals sampled, including four species of small mammals. serologic tests indicated that 25-37% of the small rodents assayed had been exposed to b. burgdorferi. immunofluorescence antibody assays specific for b. burgdorferi showed spirochete infection in ... | 1995 | 7677212 |
| ixodid ticks from panthers and bobcats in florida. | ixodid ticks were present in all 189 samples examined from 53 florida panthers (felis concolor coryi, 104 collections) and 85 bobcats (felis rufus floridana) in florida (usa) between 1974 and 1991. we identified 3,251 ticks from panthers and 918 from bobcats. specimens of dermacentor variabilis, ixodes scapularis, i. affinis, amblyomma maculatum, and a. americanum were present on 49, 39, 17, seven, and two of the 53 florida panthers, respectively, and comprised 36%, 55%, 7%, 1%, and < 1% of the ... | 1995 | 8592378 |
| cytosystematics of five north american amblyomma (acarina: ixodidae) species. | the karyotypes of 5 species of amblyomma ticks found in north america were examined for the presence and location of constitutive heterochromatin (c-bands). all specimens examined had 20 autosomes and an xx:xo sex-determining system, with the x being the largest element in the karyotype. except as noted in text, the autosomes of all species were acrocentric and heterochromatin was restricted to the centromeric region. the third largest autosome in 4 of the 5 species displayed a consistent band o ... | 1995 | 7876973 |
| origin of arachidonic acid in the salivary glands of the lone star tick, amblyomma, americanum. | the contribution of synthesis and dietary sequestration to the high arachidonate content of the lone star tick, amblyomma americanum, salivary glands was investigated by assessing the salivary metabolites of various radiolabeled fatty acid substrates administered to partially fed females. a portion of each of the fatty acids studied was incorporated into the fatty acid moiety of the phospholipid fraction. [14c]acetate was metabolized only into myristic, palmitic, palmitoleic, steric, and oleic a ... | 1995 | 7711753 |
| uptake, incorporation and redistribution of arachidonic acid in isolated salivary glands of the lone star tick. | the ability of isolated salivary glands from the lone star tick, amblyomma americanum, to take up, incorporate and redistribute [3h]arachidonic acid was examined. uptake of arachidonic acid was concentration dependent--a single salivary gland incorporated up to approximately 2.8 micrograms arachidonic acid in 60 min. over 90% of the [3h]arachidonate entering the glands was esterified and found only in the phospholipid (approximately 80%) and triglyceride (approximately 10%). essentially no radio ... | 1995 | 7742831 |
| lower temperature limits for activity of several ixodid ticks (acari: ixodidae): effects of body size and rate of temperature change. | uncoordinated activity threshold temperature, the temperature below which ticks can no longer seek a host in a coordinated manner, and the activity threshold temperature, when all activity ceases, were examined for three species of ticks found in coastal sections of new york. the mean uncoordinated activity threshold and activity threshold temperatures were determined for nymphal, female and male ixodes scapularis say, nymphal, female, and male amblyomma americanum (l.), and for female and male ... | 1995 | 7650705 |
| regulation of free arachidonic acid levels in isolated salivary glands from the lone star tick: a role for dopamine. | an important regulatory step for prostaglandin synthesis is the availability of the precursor, free arachidonic acid (aa). in isolated salivary glands of the lone star tick, amblyomma americanum (l.), the level of free aa appears to depend on higher phospholipase a2 (pla2) activity rather than decreased rates of re-esterification by lysophosphatide acyl transferase (lat). this conclusion is supported by experiments where inhibition of lat with merthiolate was without effect, while the calcium io ... | 1995 | 7655056 |
| activity of repellents applied to skin for protection against amblyomma americanum and ixodes scapularis ticks (acari: ixodidae). | twenty-nine repellents were tested on human skin for duration of activity as protectants against nymphal lone star ticks (amblyomma americanum) and against black-legged or deer ticks (ixodes scapularis say). eleven of these repellents, including deet, provided > 2 h of protection against the lone star tick. one repellent, 1-(3-cyclohexenyl-ylcarbonyl) piperidine, was effective > or = 4 h. four repellents (2 pyridines and 2 piperidines with protection lasting 2.3-3 h) showed acaricidal activity t ... | 1995 | 7616181 |
| experimental transmission of ehrlichia chaffeensis (rickettsiales: ehrlichieae) among white-tailed deer by amblyomma americanum (acari: ixodidae). | ehrlichia chaffeensis anderson, dawson & wilson, causative agent of human (predominantly monocytic) ehrlichiosis, was successfully transmitted experimentally by amblyomma americanum (l.) to white-tailed deer, odocoileus virginianus (zimmerman). deer were needle-exposed intravenously to e. chaffeensis in tissue-culture canine macrophage (dh82) cells, and 11 d later were exposed to laboratory-reared a. americanum larvae, nymphs, and adults for acquisition feeding. three months after this feeding, ... | 1995 | 7616529 |
| ehrlichiosis in a golf-oriented retirement community. | ehrlichiosis due to ehrlichia chaffeensis usually occurs sporadically or in small clusters, with an annual incidence estimated at 3 to 5 cases per 100,000 population in areas of endemic disease. the putative principal vector is the lone star tick (amblyomma americanum). we investigated an outbreak of ehrlichiosis that occurred in june 1993 among members of a golf-oriented retirement community (community a) in tennessee. the community is densely wooded and borders a wildlife-management area where ... | 1995 | 7616991 |
| physiological and nutritional responses of steers infested with varying densities of amblyomma americanum (acari: ixodidae). | the effects of varying densities of lone star tick, amblyomma americanum (l.), on measured physiological parameters of beef cattle in a controlled environment was determined. steers were infested with either 0, 20, 60, or 120 pairs of adult ticks. heart rate, respiration, rectal temperature, fecal and urine excretions, and water and feed consumption were monitored daily. blood samples were taken every 3rd d to measure cortisol, total proteins, urea nitrogen, and glucose levels. hematocrits were ... | 1995 | 8537543 |
| prostaglandin biosynthesis and subcellular localization of prostaglandin h synthase activity in the lone star tick, amblyomma americanum. | we report on prostaglandin (pg) biosynthesis in the lone star tick, amblyomma americanum. in vitro preparations of whole female ticks and internal tissues were competent to biosynthesize four pgs: pga2/pgb2, pgd2, pge2, pgf2 alpha. pga2/pgb2 was the major product under optimal conditions. pg biosynthesis by whole tick and internal tissues were sensitive to incubation conditions including, protein concentration, time, temperature, ph, and presence of a co-factor cocktail composed of reduced gluta ... | 1995 | 8541884 |
| field evaluation of deet and a piperidine repellent (ai3-37220) against amblyomma americanum (acari: ixodidae). | repellent efficacy of deet (n,n-diethyl-3-methylbenzamide) and a piperidine, ai3-37220, was evaluated topically on human volunteers against lone star tick, amblyomma americanum (l.), nymphs and adults in the field. ai3-37220, at 0.5 mg/cm2, provided > 90% repellency against adult and nymphal ticks over a 6-h test period and showed significantly better repellent efficacy than deet. deet, at the same concentration, provided 85% repellency at 0 h and deteriorated to 55% repellency at 6 h. | 1995 | 8551512 |
| temporal association of amblyomma americanum with the presence of ehrlichia chaffeensis reactive antibodies in white-tailed deer. | from 1981 through 1993, tick infestations and serum antibodies reactive to ehrlichia chaffeensis, the causative agent of human ehrlichiosis, were monitored among white-tailed deer (odocoileus virginianus) at whitehall experimental forest, clarke county, georgia (usa). neither ticks nor e. chaffeensis antibodies were detected during the first two years of the study. infestations of the lone star tick (amblyomma americanum), a suspected vector of e. chaffeensis, first were noted on deer in 1983. p ... | 1995 | 8583627 |
| dietary modification of host blood lipids affect reproduction in the lone star tick, amblyomma americanum(l.). | the feeding and reproductive performance of female lone star ticks (amblyomma americanum (l.)) infesting guinea pigs on diets containing 15% fish oil (fo) or safflower oil (so) were investigated. replete ticks fed on fo-fed guinea pigs weighed approximately 30% less than those on the so-fed guinea pigs. the lower engorged weight resulted in a similar decrease in the mass and number of eggs laid and number of larvae hatching. no effect of host dietary treatment was observed upon the reproductive ... | 1996 | 8604084 |
| ticks parasitizing humans in georgia and south carolina. | from 1990 through 1995, 913 ticks removed from 460 human patients in georgia or south carolina were identified and recorded. the majority of these specimens (758, 83.0%) were lone star ticks, amblyomma americanum. one hundred and four (11.4%) american dog ticks dermacentor variabilis, 36 (3.9%) blacklegged ticks ixodes scapularis, 9 (1.0%) gulf coast ticks amblyomma maculatum, and 6 (0.7%) brown dog ticks rhipicephalus sanguineus were also recovered. all active stages (larvae, nymphs, and adults ... | 1996 | 8636862 |
| systemic treatment of white-tailed deer with ivermectin-medicated bait to control free-living populations of lone star ticks (acari:ixodidae). | whole-kernel corn was treated with 10 mg ivermectin per 0.45 kg corn and fed at rate of approximately .45 kg/deer per day to white-tailed deer confined in the treatment pasture, whereas deer in an adjacent control pasture received a similar ration of untreated corn. treatments were dispensed from february through september of 1992 and 1993, and free-living populations of lone star ticks. amblyomma americanum (l.), were monitored in both pastures using dry-ice traps to quantify nymphs and adults ... | 1996 | 8667385 |
| cold-hardiness of a laboratory colony of lone star ticks (acari: ixodidae). | the cold-hardiness of a lone star tick, amblyomma americanum (l.), laboratory colony was characterized. fed and unfed larvae, fed and unfed nymphs, and unfed adults did not survive exposure to -17 degrees c for 7 d. after an 8-d exposure to -10 degrees c, adults tolerated cold better than immatures and unfed specimens fared better than fed ticks. exposing unfed 6-wk-old (postmolt) adult males and females to -15 degrees c for increasing intervals up to 2 h suggests that males were more tolerant t ... | 1996 | 8699473 |
| a new borrelia infecting lone star ticks. | 1996 | 8531586 | |
| ehrlichia-like 16s rdna sequence from wild white-tailed deer (odocoileus virginianus). | the reservoir hosts of ehrlichia chaffeensis, etiologic agent of human ehrlichiosis are unknown. initially, white-tailed deer (wtd) were serologically implicated as possible reservoirs of e. chaffeensis. subsequent studies showed that wtd were susceptible to infection with e. chaffeensis and that deer-to-deer transmission by a tick vector, amblyomma americanum, is possible under experimental conditions. to determine if wild wtd were infected with e. chaffeensis, whole blood was collected from 10 ... | 1996 | 8627501 |
| identification of an uncultivable borrelia species in the hard tick amblyomma americanum: possible agent of a lyme disease-like illness. | bites from the hard tick amblyomma americanum are associated with a lyme disease-like illness in the southern united states. to identify possible etiologic agents for this disorder, a. americanum ticks were collected in missouri, texas, new jersey, and new york and examined microscopically. uncultivable spirochetes were present in approximately 2% of the ticks. borrelia genus-specific oligonucleotides for the flagellin and 16s rrna genes were used for amplification of dna. products were obtained ... | 1996 | 8568302 |
| molecular cloning of delta 9 fatty acid desaturase from the protozoan tetrahymena thermophila and its mrna expression during thermal membrane adaptation. | in response to a decrease in its growth temperature, the protozoan tetrahymena is known to increase the level of unsaturated fatty acids in its membrane phospholipids so as to maintain the correct physical state (fluidity) of the membranes. in this organism, synthesis of unsaturated fatty acids is initiated by delta 9 acyl-coa desaturase. our previous studies have shown that, during cold adaptation, the activity of microsomal palmitoyl- and stearoyl-coa desaturase increases, reaching a maximal l ... | 1996 | 8694777 |
| site-specific geographic association between amblyomma americanum (acari: ixodidae) infestations and ehrlichia chaffeensis-reactive (rickettsiales: ehrlichieae) antibodies in white-tailed deer. | serum samples from white-tailed deer, odocoileus virginianus zimmermann, collected from 1982 through 1992 from the southeastern united states were tested for antibodies reactive to ehrlichia chaffeensis anderson, dawson, jones, & wilson, the causative agent of human ehrlichiosis. results were compared between areas based on known infestations of the lone star tick, amblyomma americanum l., a suspected vector of e. chaffeensis. one hundred and twenty-five of 300 (41.7%) deer tested positive (> or ... | 1996 | 8906920 |
| seasonal activity and relative abundance of amblyomma americanum in mississippi. | ecological investigations of the lone star tick, amblyomma americanum (l.), were conducted in 3 adjacent 60-m2 plots, located in noxubee national wildlife refuge, noxubee county, mississippi. ticks were collected weekly from july 1992 to july 1993 by flagging randomly selected lanes. during the year, larval ticks were collected first in early july, with peak numbers in september, and they were collected no later than late october. nymphal ticks were collected from mid-march to late october, with ... | 1996 | 8906916 |
| alteration of arachidonate levels in tick salivary glands by dietary modification of host blood lipids. | tick saliva contains prostaglandins of the 2-series, believed to facilitate bloodmeal acquisition. because ticks cannot synthesize the prostaglandin precursor, arachidonic acid, investigations were undertaken to study the uptake, incorporation, and distribution of arachidonic acid in the salivary glands of the lone star tick in vitro and in vivo. uptake of [3h]arachidonate by isolated salivary glands was reduced in the presence of low concentrations of arachidonic or eicosapentaenoic acids, but ... | 1996 | 8541571 |
| a self-medicating applicator for control of ticks on deer. | a self-medicating applicator for killing ticks on deer and domestic ungulates by passive transfer of acaricides during feeding is described. the applicator consists of a barrel divided into a food bin (above) and a sealed self-contained acaricide reservoir (below) with a vertical, centrally-located ceramic column that extends from the reservoir into the food bin. acaricide is drawn up the column from the sealed reservoir by absorption. animals attracted to the food in the device acquire the acar ... | 1996 | 8744707 |
| effects of pyriproxyfen on engorged females and newly oviposited eggs of the lone star tick (acari:ixodidae). | engorged females and 1- to 3-d-old eggs of the lone star tick, amblyomma americanum (l), were exposed to 9 treatments of pyriproxyfen (4, 8, and 16 micrograms/cm2) in glass vials at exposure periods of 7 d, 14 d, and continuous at each dosage level. treatment of newly engorged females did not affect the number of females ovipositing, but the number of eggs oviposited decreased as dosage and exposure time increased. complete inhibition of egg hatch occurred at all treatment levels except that of ... | 1996 | 8840677 |
| survival and water-balance characteristics of unfed adult amblyomma cajennense (acari: ixodidae). | off-host survival, water balance, and cold tolerance of unfed adult, cayenne ticks, amblyomma cajennense (f.), were examined to evaluate species characteristics important to zoogeography and off-host ecology. survivorship decreased when males and females were subjected to progressively drier constant environmental conditions. average maximum survival was 641.2 and 682.5 d at 85% rh and 23 degrees c (2.98 mm hg) for males and females, respectively. mean survival in both sexes was progressively le ... | 1996 | 8906907 |
| tick avoidance behaviors associated with a decreased risk of anti-tick salivary gland protein antibody seropositivity in military personnel exposed to amblyomma americanum in arkansas. | during april through september 1990, 399 military personnel who originated from either fort chaffee, arkansas (n = 236) or fort wainwright, alaska (n = 163) were studied during maneuvers in tick-infested areas at fort chaffee. study subjects completed a questionnaire and had pre- and post-maneuvers serum specimens analyzed for antibodies to several rickettsial and ehrlichial agents and to amblyomma americanum (lone star tick) salivary gland proteins (anti-tick saliva antibodies [atsa], a biologi ... | 1996 | 8916798 |
| salivary gland changes and host antibody responses associated with feeding of male lone star ticks (acari:ixodidae). | the goal of this study was to demonstrate that male lone star ticks, amblyomma americanum (l.), actively feed on rabbits during attachment and that the host is capable of mounting an immune response against male salivary gland proteins. during attachment, it was shown that male ticks salivary glands hypertrophy. an enzyme-linked immunosorbent assay was used to detect rabbit serum proteins in the midgut of previously attached male ticks. sds-polyacrylamide gel electrophoresis showed that the prot ... | 1996 | 8699458 |
| human ehrlichiosis--maryland, 1994. | ehrlichiosis is an emerging tickborne infectious disease caused by obligate intracellular, gram-negative rickettsia that infect leukocytes. human monocytic ehrlichiosis (hme) is caused by ehrlichia chaffeensis and is believed to be transmitted by amblyomma americanum (the lone star tick). most hme cases have been reported in southeastern and south-central states. during may-july 1994, five cases of serologically confirmed hme were identified among residents of maryland. all five persons lived ne ... | 1996 | 8926996 |
| cloning and sequence of a gene for a homologue of the c subunit of the v-atpase from the salivary gland of the tick amblyomma americanum (l). | a 1084 base pair partial cdna showing similarity to the c subunit of the vacuolar atpase (v-atpase) was isolated on a clone from a cdna library made from salivary glands from 3-day-old feeding adult amblyomma americanum (l.) female ticks. the 5' end was completed using primer extension and the two pieces joined to form a complete cdna of 1373 bp. this mrna is expressed in embryos and the salivary glands of unfed adults and adult females at all stages of feeding. specific inhibitors of the v-atpa ... | 1997 | 9013257 |
| tick-raccoon associations and the potential for lyme disease spirochete transmission in the coastal plain of north carolina. | raccoons (procyon lotor) were live-trapped and examined for ticks from july 1990 to july 1993 in the coastal plain of north carolina on marine corps base, camp lejeune, north carolina (usa). five species of ixodid ticks were found on 351 (78%) of 449 raccoons. amblyomma americanum was the most abundant tick found on raccoons. dermacentor variabilis, ixodes texanus, and ixodes scapularis were frequently collected, while ixodes cookei were rarely collected from raccoons. tick burdens were not affe ... | 1997 | 9027688 |
| identification and characterization of anticoagulant activities in the saliva of the lone star tick, amblyomma americanum (l.). | anticoagulant activities against both the extrinsic and intrinsic coagulation pathways were identified in the saliva of partially fed female lone star ticks, amblyomma americanum (l.). the activities of factor xa and thrombin in the common pathway of the coagulation cascade were inhibited by tick saliva. the greatest anticoagulant activities were found in the saliva of ticks weighing more than 200 mg. the anticoagulant activities in tick saliva could be detected without preincubation of tick sal ... | 1997 | 9057694 |
| prostaglandin biosynthesis by salivary glands isolated from the lone star tick, amblyomma americanum. | salivary glands separated from internal tissues of the lone star tick, amblyomma americanum, are competent to synthesize prostaglandins (pgs). using an in vitro pg biosynthesis assay four major pgs, namely, pga2/pgb2, pgd2, pge2, and pgf2 alpha were synthesized. under standard assay conditions pga2/pgb2 was the predominant product. salivary tissues as well as non-salivary internal tissues were capable of pg biosynthesis. we observed that storing ticks at -80 degrees c for 3 months resulted in re ... | 1997 | 9090120 |
| pyriproxyfen effects on newly engorged larvae and nymphs of the lone star tick (acari:ixodidae). | newly engorged larvae and nymphs of the lone star tick, amblyomma americanum (l.), were exposed to 9 treatments of pyriproxyfen in glass vials consisting of dosages of 4, 8, and 16 micrograms/cm2 for 7 d, 14 d, and continuous exposure periods at each concentration. treatment of newly engorged larvae resulted in decreased molting, altered postmolt defecation, and nymphal survival with results being dose and exposure dependent. molting inhibition ranged from 35.9 to 68.4%. successfully molted nymp ... | 1997 | 9103764 |
| development and use of specific polymerase reaction for the detection of an organism resembling ehrlichia sp. in white-tailed deer. | the role of white-tailed deer (odocoileus virginianus) in the epidemiology of ehrlichia chaffeensis and the agent of human granulocytic ehrlichiosis (hge) is not fully understood, and diagnostic procedures may be complicated by the recent detection of 16s rdna sequence from an ehrlichia sp.-like organism in wild deer. a specific forward primer (dga) and an ehrlichia spp. reverse primer (ga1ur) were constructed to amplify this new, distinct ehrlichia sp.-like 16s rdna. the dga primer, a forward p ... | 1997 | 9131554 |
| some factors affecting infestation of white-tailed deer by blacklegged ticks and winter ticks (acari:ixodidae) in southeastern missouri. | a total of 5,669 ticks of 4 species was collected from 515 hunter killed, white-tailed deer. odocoileus virginianus (zimmerman), in southeastern missouri from 1993 through 1995. the american dog tick, dermacentor variabilis (say) (4 adults), the lone star tick, amblyomma americanum (l.) (57 adults, 2 nymphs), the blacklegged tick, ixodes scapularis (say) (3,120 adults), and the winter tick, dermacentor albipictus (packard) (2.059 adults, 436 nymphs, 1 larva) were collected. patterns of adult d. ... | 1997 | 9151505 |
| assay for phenoloxidase activity in amblyomma americanum, dermacentor variabilis, and ixodes scapularis. | phenoloxidase activity in amblyomma americanum, dermacentor variabilis, and ixodes scapularis was assayed. no phenoloxidase activity was detected compared to high activity through time in larvae of the greater wax moth (galleria mellonella). we conclude that activated prophenoloxidase does not act as an opsonin in ixodid ticks tested to date. | 1997 | 9194851 |