TitleAbstractYear(sorted ascending)
molecular evidence for novel tick-associated spotted fever group rickettsiae from thailand.ticks are of considerable medical and veterinary importance because they directly harm the host through their feeding action and indirectly through vectoring many bacterial pathogens. despite many ticks being known from thailand, very little is known about the bacteria they may harbor. we report here the results of a survey of tick-associated bacteria in thailand. a total of 334 individuals representing 14 species of ticks in five genera were collected from 10 locations in thailand and were exam ...200312693853
repellent efficacy of deet and kbr 3023 against amblyomma hebraeum (acari: ixodidae).the bont tick, amblyomma hebraeum koch, is the principal vector of rickettsia africae, the agent of african tick bite fever, in southern africa. in contrast to most other hard ticks, members of the genus amblyomma exhibit a characteristic attack host-seeking behavior. the efficacy of topically applied 20% lotions of deet (diethyl-3-methylbenzamide), the currently considered reference repellent substance, and kbr 3023, a recently developed piperidine compound, was evaluated against laboratory-rea ...200312693855
amblyomma aureolatum (pallas, 1772) and amblyomma ovale koch, 1844 (acari: ixodidae): hosts, distribution and 16s rdna sequences.dna sequences of amblyomma aureolatum (pallas, 1772) and amblyomma ovale koch, 1844 were obtained to determine genetic differences between these tick species. collections of these species are discussed in relation to distribution and hosts. seven ticks collections (four from brazil, one from argentina, one from uruguay and one from usa) house a total of 1272 a. aureolatum (224 males, 251 females, 223 nymphs and 574 larvae) and 1164 a. ovale (535 males, 556 females, 66 nymphs and 7 larvae). the l ...200312719142
exotic ticks introduced into the united states on imported reptiles from 1962 to 2001 and their potential roles in international dissemination of diseases.since 1962, a total of 29 species of exotic ticks have been introduced into the united states on imported reptiles, with 17 species from the genus amblyomma, 11 from the genus aponomma and one from the genus hyalomma. in the absence of measures to control introduction of these importations, some exotic tick species will develop breeding colonies and become established as indigenous species and some tickborne diseases may be introduced to wreak havoc among susceptible native populations. however, ...200312719143
effect of fast protein liquid chromatography fractionated salivary gland extracts from different ixodid tick species on interleukin-8 binding to its cell receptors.interleukin-8 plays a critical role in inflammatory processes. hence generation of molecules with anti-il-8 activity is likely to be important for successful feeding and for survival of the ticks. anti-il-8 activity was studied in saliva of three ixodid tick species--dermacentor reticulatus (fabricius, 1794), rhipicephalus appendiculatus neumann, 1901, and amblyomma variegatum (fabricius, 1794). the greatest activity was shown in saliva prepared from d. reticulatus. the activity was attributed t ...200312735728
rna interference in ticks: a study using histamine binding protein dsrna in the female tick amblyomma americanum.rna interference (rnai), a gene silencing process, has been recently exploited to determine gene function by degrading specific mrnas in several eukaryotic organisms. we constructed a double stranded rna (dsrna) from a previously cloned putative amblyomma americanum histamine binding protein (hbp) to test the significance of using this methodology in the assessment of the function and importance of gene products in ectoparasitic ticks. the female salivary glands incubated in vitro with hbp dsrna ...200312752664
efficacy of two 65% permethrin spot-on formulations against induced infestations of ctenocephalides felis (insecta: siphonaptera) and amblyomma americanum (acari: ixodidae) on beagles.the efficacy of two formulations of a topically applied 65% permethrin spot-on (defend exspot treatment for dogs, schering-plough animal health) was evaluated against experimental infestations of the cat flea ctenocephalides felis and the lone star tick amblyomma americanum in dogs. eighteen dogs were randomly assigned to treatment with 65% permethrin in either diethylene glycol monomethyl ether (dgme; original formulation) or propylene glycol monomethyl ether (pgme) or to be untreated as a cont ...200312756635
ehrlichia chaffeensis: a prototypical emerging pathogen.ehrlichia chaffeensis is an obligately intracellular, tick-transmitted bacterium that is maintained in nature in a cycle involving at least one and perhaps several vertebrate reservoir hosts. the moderate to severe disease caused by e. chaffeensis in humans, first identified in 1986 and reported for more than 1,000 patients through 2000, represents a prototypical "emerging infection." knowledge of the biology and natural history of e. chaffeensis, and of the epidemiology, clinical features, and ...200312525424
survey of ixodid tick species on domestic cats in japan.various species of ixodid ticks, attached to domestic cats in japan, were identified in spring (april to june) and autumn (september to november). in the spring, a total of 282 ticks, including 61 larvae, 70 nymphs, 127 females and 24 males were collected from 126 cats. of these, 264 were identified up to the species level. in the spring, haemaphysalis longicornis was the most frequently (39.7%, 50/126) found tick species on feline hosts, followed by ixodes ovatus (35.0%, 44/126), ixodes nippone ...200312531297
two novel non-cationic defensin-like antimicrobial peptides from haemolymph of the female tick, amblyomma hebraeum.two non-cationic defensin-like antimicrobial peptides, named amblyomma defensin peptide 1 and amblyomma defensin peptide 2, were identified from the hard tick, amblyomma hebraeum, by a combination of suppression subtractive hybridization for differentially expressed genes and proteomics. cdna clones encoding each of these two defensin-like antimicrobial peptides were isolated from the differentially expressed cdna library of the tick synganglia (central nervous system). the preproproteins deduce ...200414705963
[rickettsia africae, the agent of african tick-bite fever: an emerging pathogen in the west indies and reunion island (indian ocean)].rickettsia africae is the agent of african tick bite fever, an emerging disease transmitted by amblyomma ticks in sub-saharan africa. in 1998, we reported the first documented case of r. africae in the new world, in a patient who had returned from guadeloupe. in order to confirm the presence of r. africae in the west indies, entomologic surveys were conducted from 1999 to 2003 to collect amblyomma, which are considered as potential vectors and reservoirs of the bacteria. ticks were used as epide ...200415462202
morphological characterization of the ovary and vitellogenesis dynamics in the tick amblyomma cajennense (acari: ixodidae).in this work we describe the internal morphology of the female reproductive system of the cayenne tick amblyomma cajennense. this system is represented by a panoistic ovary, which lacks nurse cells in the germarium. this ovary consists of a single tube, in which a large number of oocytes develop asynchronously, thus accompanying the processes of yolk deposition in the oocytes. the oocytes were classified into stages that varied from i to v, according to: cytoplasm appearance, presence of the ger ...200415482894
rickettsia parkeri in amblyomma triste from uruguay.our goal was to detect whether spotted fever group rickettsia are found in the suspected vector of rickettsioses, amblyomma triste, in uruguay. rickettsia parkeri was detected in a. triste, which suggests that this species could be considered a pathogenic agent responsible for human rickettsioses in uruguay.200415496258
amblyomma americanum salivary gland homolog of nsec1 is essential for saliva protein secretion.soluble n-ethylmaleimide-sensitive factor attachment protein receptor proteins assemble in tight core complexes which promote fusion of carrier vesicles with target compartments. members of this class of proteins are expressed in all eukaryotic cells and distributed in distinct subcellular compartments. all vesicle transport mechanisms known to date have an essential requirement for a member of the sec1 protein family, including the nsec1 in regulated exocytosis. a homolog of nsec1 was cloned an ...200415504350
a thrombin inhibitor from the ixodid tick, amblyomma hebraeum.a novel thrombin inhibitor named amblin was identified from the haemolymph of the ixodid (hard) tick, amblyomma hebraeum, and the coding cdna was isolated from a tick cdna library. this cdna codes for a preprotein of 166 amino acids, including a predicted signal peptide composed of 15 amino acids n-terminal to the mature amblin. the 151-amino-acid mature amblin contains 14 cysteines and two kunitz-like domains. it displays high sequence similarity with a tissue factor pathway inhibitor (tfpi), i ...200415527983
characterization of spotted fever group rickettsiae in flea and tick specimens from northern peru.evidence of spotted fever group (sfg) rickettsiae was obtained from flea pools and individual ticks collected at three sites in northwestern peru within the focus of an outbreak of febrile disease in humans attributed, in part, to sfg rickettsia infections. molecular identification of the etiologic agents from these samples was determined after partial sequencing of the 17-kda common antigen gene (htra) as well as pairwise nucleotide sequence homology with one or more of the following genes: glt ...200415528680
borrelia species in host-seeking ticks and small mammals in northern florida.the aim of this study was to improve understanding of several factors related to the ecology and environmental risk of borrelia infection in northern florida. small mammals and host-seeking adult ticks were collected at several sites, and specimens were tested for the presence of borrelia species, primarily by pcr amplification. tissues from some vertebrates and ticks were initially cultured in bsk-h medium to isolate spirochetes, but none were recovered. however, comparison of partial flagellin ...200415528699
[random amplified polymorphic dna analysis of the genomes among 7 species of ticks].to study genomic polymorphic dna and genetic distance of 7 species of ticks.200415587156
nested pcr for detection and genotyping of ehrlichia ruminantium: use in genetic diversity analysis.ehrlichia ruminantium, the agent of cowdriosis transmitted by amblyomma ticks, presents an extensive genetic and antigenic diversity of key importance for vaccine formulation. two means of nested polymerase chain reaction (pcr) targeting were developed to conduct molecular epidemiology studies in the caribbean and africa. the first used a conserved dna fragment for detection of the pathogen in animals and vectors, and the second relied on the polymorphic map1 gene for genotyping. as compared to ...200415604477
successful infestation by amblyomma pseudoconcolor and a. cooperi (acari: ixodidae) on horses.the host relationships for most species of the genus amblyomma are poorly known in brazil. the ability of a. pseudoconcolor and a. cooperi to successfully feed on horses was investigated during ongoing research on the life cycle of these two species, which are primarily associated with wildlife. results of these experiments suggest that horses are potential hosts for the adult stages of both species.200415604498
the caribbean amblyomma program: some ecologic factors affecting its success.the caribbean amblyomma program has been operational for 8 years. however, owing to funding availability, some islands did not commence eradication activities until late 1997. during the past 2 years, 6 of the 9 islands (st. kitts, st. lucia, anguilla, montserrat, barbados, and dominica) under the program have attained the status of provisional freedom from the tropical bont tick (tbt). there are several administrative and technical reasons why the attainment of the program goals took longer tha ...200415604510
an in vitro larval immersion microassay for identifying and characterizing candidate acaricides.we have optimized a larval immersion microassay (lim) that offers superior sensitivity, flexibility to accommodate multiple formulations, and a robust capability for rapidly screening many compounds with a minimal requirement of test article for evaluation. dose-response studies were conducted for representative members from the organophosphate, pyrethroid, pyrazole, carbamate, macrocyclic lactone, and formamidine chemistries against amblyomma americanum (l.). time-response experiments revealed ...200415605642
rickettsia bellii and rickettsia amblyommii in amblyomma ticks from the state of rondônia, western amazon, brazil.this study evaluates the rickettsial presence in amblyomma ticks from eight areas of the amazon forest in rondônia, brazil. the following tick species (number in parentheses) were examined: amblyomma ovale koch (121), amblyomma cajennense (f.) (41), amblyomma naponense (packard) (36), amblyomma scalpturatum neumann (35), amblyomma oblongoguttatum koch (30), amblyomma incisum neumann (27), amblyomma rotundatum koch (16), amblyomma coelebs neumann (10), and amblyomma humerale koch (6). ticks were ...200415605647
detection of ehrlichia chaffeensis in adult and nymphal amblyomma americanum (acari: ixodidae) ticks from long island, new york.the lone star tick, amblyomma americanum (l.), has increased in abundance in several regions of the northeastern united states, including areas of long island, ny. adult and nymphal stage a. americanum collected from several sites on long island were evaluated for infection with ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (hme), by using a nested polymerase chain reaction assay. fifty-nine (12.5%) of 473 adults and eight of 113 pools of five nymphs each (estimated ...200415605650
susceptibility of mice (mus musculus) to repeated infestation with amblyomma americanum (acari: ixodidae) ticks.laboratory mice, mus musculus (l.), balb/c strain, were assessed for their ability to develop resistance to repeated infestation by amblyomma americanum (l.) ticks. mice were infested five consecutive times with a. americanum nymphs. no decrease in tick viability was seen after five infestations, suggesting that balb/c mice do not develop immune-mediated resistance to a. americanum. in contrast, tick viability was significantly reduced in the second infestation of a new zealand white rabbit, a l ...200415605656
effects of 20-hydroxyecdysone and other hormones on egg development, and identification of a vitellin-binding protein in the ovary of the tick, amblyomma hebraeum.partially fed adult female amblyomma hebraeum ticks were injected with 20-hydroxyecdysone (20e; up to 43 microg/g body weight (bw)), juvenile hormone iii (jh iii; up to 100 microg/g bw), bovine insulin (up to 2000 mu/g bw), or triiodothyronine (up to 200 ng/g bw) in an attempt to stimulate vitellogenesis. of these, only 20e stimulated synthesis and release of vitellogenin (vg). immunoblot analysis revealed that vg-synthesis occurred in the fat body. however, consistent with earlier observations ...200415183281
development of a novel self-medicating applicator for control of internal and external parasites of wild and domestic animals.four trials, three in the united states and one in south africa, were conducted to evaluate the potential value of a novel self-medicating applicator in the passive control of gastrointestinal nematodes in cattle and deer, and of files and ticks on cattle using oil-based treatments. the results of the trials demonstrated that this applicator is an effective and practical device for the passive treatment of both deer and cattle for trichostrongyle infections using the endectocide, moxidectin (cyd ...200415185574
phylogenetic analysis of the francisella-like endosymbionts of dermacentor ticks.bacterial endosymbionts with significant homology to francisella tularensis (gamma-proteobacteria) have been described from at least five species of ticks in three different genera, including two north american dermacentor species [d. andersoni stiles and d. variabilis (say)]. the evolutionary relationships among the francisella-like endosymbionts (fle) from different hosts and between fle and the arthropod-borne pathogen f. tularensis are not known. a 1,169-base fragment of the 16s rdna and a 7 ...200415185926
study of the seasonal dynamics, life cycle, and host specificity of amblyomma aureolatum (acari: ixodidae).in the first part of this study, monthly infestation by ticks was evaluated on dogs from december 2000 to november 2002 in the rural area of taiaçupeba, são paulo. adults of amblyomma aureolatum (pallas) were found on dogs in all months, with a mean prevalence per month of 46.9 +/- 15.7% (range, 25-80%). the mean tick relative abundance per month was 2.4 +/- 2.7 ticks (range, 0.5-14 ticks), and the mean tick mean intensity per month was 4.7 +/- 4.2 ticks (range, 1.5-23.3 ticks). no a. aureolatum ...200415185932
molecular evidence for a spotted fever group rickettsia species in the tick amblyomma longirostre in brazil.two amblyomma longirostre adult male ticks were collected from a brazilian porcupine coendou prehensilis l. in the state of rondonia, western amazon, brazil. the two ticks were pooled for dna extraction and tested for the presence of rickettsial dna by amplifying portions of the glta, 17-kda, ompa, and ompb rickettsial genes by polymerase chain reaction (pcr). portions of the four genes were amplified from the sample and subsequently sequenced. these results indicated the presence of a rickettsi ...200415185961
human otoacariasis: a retrospective study from an area of sri lanka.intra-aural ticks were present in 870 (15.2%) of 5714 patients who reported with ear-related complaints to the ear, nose and throat ward at ratnapura hospital, sabaragamuwa province, sri lanka, from january 2000 to december 2001. a retrospective study of 383 of these otoacariasis cases showed that the majority (70.8%) of surgically-removed ticks were nymphal amblyomma integrum, together with nymphal and adult rhipicephalus haemaphysaloides, r. sanguineus, hyalomma brevipunctata, h. marginatum, a ...200415186938
an updated list of the ticks of ghana and an assessment of the distribution of the ticks of ghanaian wild mammals in different vegetation zones.twenty one species of ticks belonging to five genera of the family ixodidae (order acari, sub-order ixodida) - amblyomma, haemaphysalis, hyalomma, ixodes and rhipicephalus (including the sub-genus rhipicephalus (boophilus)) - were collected from 1260 mammals, representing 29 species, 14 families and 6 orders, in four vegetation zones in ghana during the period 1971-1978. four other species were collected from humans in 1977. in all, eight species appeared to be new records for ghana: amblyomma t ...200415191626
a proteomics approach to characterizing tick salivary secretions.the saliva of ticks contains a complex mixture of bioactive molecules including proteins that modulate host responses ensuring successful feeding. the limited amount of saliva that can be obtained from ticks has hampered characterization of salivary proteins using traditional protein chemistry. recent improvements in two-dimensional gel electrophoresis, mass spectrometry, and bioinformatics provide new tools to characterize small amounts of protein. these methods were employed to characterize sa ...200415198089
cutaneous hypersensitivity induced in rabbits by extracts of the tick amblyomma cajennense (acari: ixodidae).the cutaneous hypersensitivity test was used to correlate host resistance to ticks and type of reactions elicited by aomblyomma cajennense (fabricius, 1787) tick extract in rabbits. rabbits were divided into 3 groups of 2 animals each: naive, pre-infested and control. cutaneous hypersensitivity was induced by intradermal inoculation of 25 microg extract in 0.03 ml of phosphate buffered saline (pbs) in rabbit ears. control rabbits were inoculated with pbs only. the ear thickness was measured with ...200415214693
cross-reactivity between antigens from amblyomma cajennense and a. hebraeum (acari: ixodidae).laboratory animals exposed to feeding ticks develop resistance which is reflected by a decline in tick engorgement weight, egg-laying by adults and reduced egg viability. serum antibodies from these hosts and their reaction with tick antigens have been detected by different methods, including precipitation techniques, immunofluorescent techniques, elisa and western blots. however, little is known about the effects of antibodies on ticks that engorge on resistant hosts, or which tissues of the ti ...200415214694
spotted fever group rickettsiae from ticks captured in sudan.ticks were collected from ruminants in various areas of sudan in 1998 and 2000. primer pairs of rickettsial citrate synthase gene (glta) and a spotted fever group (sfg) rickettsial 190-kda surface antigen gene (rompa), respectively, were used for identification. polymerase chain reaction (pcr)-positive products were used for dna sequencing. the glta gene was detected in 55% of the ticks examined (57/104). among the 57 ticks studied, 19 were positive for the rompa gene. thus, 18% of the ticks exa ...200415218219
a new type of antimicrobial protein with multiple histidines from the hard tick, amblyomma hebraeum.a novel 11 kda antimicrobial protein, named as hebraein, and having a unique amino acid sequence, was purified from the hemolymph of fed female amblyomma hebraeum ticks. a full-length cdna clone encoding hebraein was isolated from a cdna library made from tick synganglia. hebraein consists of 102 amino acids, including 6 cysteine residues; has 9 histidines in its c-terminal domain that are mainly present as hx repeats; and has no significant similarity to any known protein. the secondary structu ...200415247144
ectoparasites of gray squirrels in two different habitats and screening of selected ectoparasites for bartonellae.gray squirrels, sciurus carolinensis, were livetrapped in 2 different habitat types, woodland (67 squirrels) and parkland (53 squirrels), in southeastern georgia. ectoparasites were recovered from anesthetized squirrels and compared between hosts from the 2 habitats. because of the absence of low vegetation in parkland habitats, it was hypothesized that the ectoparasite fauna, especially ticks and chiggers, would be more diverse on woodland squirrels. the results were generally in agreement with ...200415270090
ticks (acari: ixodidae) parasitizing wild carnivores in phu khieo wildlife sanctuary, thailand.ixodid ticks were collected and identified from 8 wild carnivore species in phu khieo wildlife sanctuary, northeastern thailand. six tick species belonging to 4 genera were recovered and identified from 132 individuals. these included amblyomma testudinarium (n = 36), haemaphysalis asiatica (n = 58), h. hystricis (n = 31), h. semermis (n = 3), rhipicephalus haemaphysaloides (n = 3), and ixodes granulatus (n = 1). leopard cats (prionailurus bengalensis) (n = 19) were infested with 4 tick species, ...200415270119
amblyomma cajennense ticks induce immediate hypersensitivity in horses and donkeys.since host immune reaction to ticks interferes with tick-borne pathogen transmission, it is important to recognize naturally occurring tick-host immune relationships to better understand the epidemiology of such infectious diseases. amblyomma cajennense is an important tick-borne disease vector in the neotropical region and horses maintain it in domestic environments. in the present work intradermal testing of a. cajennense tick exposed horses and donkeys using crude tick antigens was used to ev ...200415285143
first record of immature stages of amblyomma tigrinum (acari: ixodidae) on wild birds in chile.for the first time, larvae and nymphs of amblyomma tigrinum ticks were found on three species of wild birds (zenaida auriculata, callipepla californica and nothoprocta perdicaria) in chile. a significant higher number of a. tigrinum was found on fledglings of z. auriculata and n. perdicaria than on adults of these species of birds. a significant higher number was also observed on n. perdicaria living in non-irrigated areas as compared with irrigated areas. infestation levels were 6.5, 6.3 and 10 ...200415285147
disease agents in amblyomma americanum from northeastern georgia.amblyomma americanum (lone star tick) is known or suspected to vector several organisms that are implicated as human pathogens, including ehrlichia chaffeensis, e. ewingii, and borrelia lonestari. these three agents have also been detected in white-tailed deer (odocoileus virginianus). because northeastern georgia has a high abundance of both lone star ticks and white-tailed deer, and one of these organisms, e. chaffeensis, is already known to be endemic in the area, we assayed individual adult ...200415311471
ehrlichia prevalence in amblyomma americanum, central texas. 200415338551
water relations in eggs of the lone star tick, amblyomma americanum, with experimental work on the capacity for water vapor absorption.this study shows that water stress is not countered in eggs of the lone star tick, amblyomma americanum (l.), using water vapor, and suggests involvement of liquid water as a developmental cue. eggs fail to maintain an equilibrium water content in subsaturated air, hence, gain not equal to loss, with net water losses occurring at relative humidities near saturation and these eggs exhibit a three-fold drop in viability, but not incubation period, as compared to eggs held in saturated air. amblyom ...200415347026
susceptibility of mosquito and tick cell lines to infection with various flaviviruses.the genus flavivirus consists of more than 70 virus species and subtypes, the majority of which are transmitted by mosquitoes or ticks, although some have no known vector (nkv). the ability of these viruses to infect cultured cells derived from mosquito or tick species offers a useful insight into the suitability of such vectors to harbour and replicate particular viruses. we undertook a comparative study of the susceptibility of mammalian vero cells, a clonal mosquito cell line (c6/36) and rece ...200415347394
some observations on the sero-prevalence of heartwater and tick infestation in zambian goats.a survey was carried out to define the distribution of heartwater in goats that originated from six districts in communal grazing semi-arid areas of zambia. a total of 181 samples (40.1%) out of 451 serum samples from adult goats were positive for ehrlichia ruminantium antibodies after screening using indirect map-1b antigen elisa technique with statistically significant differences (p < 0.01) between the six districts. out of 1 036 adult goats examined for tick infestation, 105 were infested by ...200415373339
detection of rickettsia africae in patients and ticks along the coastal region of cameroon.rickettsia africae was identified in seven (6%) of 118 patients with acute fevers of unknown etiology proven not to be malaria or typhoid fever from clinics along the coastal region of cameroon by polymerase chain reaction (pcr) amplification and sequencing of the citrate synthase (glta) and outer membrane protein a (ompa) genes of rickettsia. the majority (71%) of the patients were female. clinical manifestations included fever (100%), headache (71%), myalgia (71%), arthralgia (43%), pulmonary ...200415381820
rickettsia parkeri: a newly recognized cause of spotted fever rickettsiosis in the united states.ticks, including many that bite humans, are hosts to several obligate intracellular bacteria in the spotted fever group (sfg) of the genus rickettsia. only rickettsia rickettsii, the agent of rocky mountain spotted fever, has been definitively associated with disease in humans in the united states. herein we describe disease in a human caused by rickettsia parkeri, an sfg rickettsia first identified >60 years ago in gulf coast ticks (amblyomma maculatum) collected from the southern united states ...200414999622
first culture isolation of borrelia lonestari, putative agent of southern tick-associated rash illness.southern tick-associated rash illness (stari) is a lyme disease-like infection described in patients in the southeastern and south-central united states, where classic lyme disease is relatively rare. stari develops following the bite of a lone star tick (amblyomma americanum) and is thought to be caused by infection with an "uncultivable" spirochete tentatively named borrelia lonestari. in this study, wild lone star ticks collected from an area where b. lonestari is endemic were cocultured in a ...200415004069
how much pilocarpine contaminates pilocarpine-induced tick saliva?pilocarpine is often applied or injected into ticks to induce salivation, and the resulting saliva used to test for various pharmacological, biochemical and immunological activities. to measure the amount of pilocarpine in pilocarpine-induced tick saliva, an hplc-ms/ms method, based on capillary strong cation exchange chromatography online with an ion trap mass spectrometer, was used to measure pilocarpine in the pg to ng range. results indicate large concentrations of pilocarpine in ixodes scap ...200415009442
amblyomma americanum salivary glands: double-stranded rna-mediated gene silencing of synaptobrevin homologue and inhibition of pge2 stimulated protein secretion.protein secretion into the saliva from the tick salivary glands is due to exocytosis of vesicular membrane bound granular material regulated by snare complex proteins after salivary gland stimulation by pge2 [insect biochem. mol. biol. 32 (2002) 1711]. proteins associated with vesicles (v-snares) are essential components of the exocytotic process. synaptobrevin is a key v-snare in all secreting cells studied to date. a vesicle-associated synaptobrevin cdna fragment homologue from the salivary gl ...200415041024
ehrlichia ruminantium grows in cell lines from four ixodid tick genera.continuous cell lines from the ticks amblyomma variegatum, boophilus decoloratus, boophilus microplus, hyalomma anatolicum anatolicum, ixodes scapularis, ixodes ricinus and rhipicephalus appendiculatus were tested for ability to support growth of the rickettsial pathogen ehrlichia (previously cowdria) ruminantium. five e.ruminantium isolates, from west africa, south africa and the french west indies, were used. twelve tick cell lines were inoculated with e.ruminantium derived either from culture ...200415053931
occurrence of the gulf coast tick (acari: ixodidae) on wild and domestic mammals in north-central oklahoma.parasitic life stages of amblyomma maculatum koch were collected from domestic cattle and several species of wild mammals during a 3.5-yr study (may 1998-october 2001) in north-central oklahoma. adult ticks were the predominant life stage collected from cattle, white-tailed deer, coyotes, and raccoons, whereas only immature ticks were collected from cotton rats and white-footed mice. the prevalence of adult a. maculatum on white-tailed deer (n = 15) examined in june, july, and august 1998 was 80 ...200415061275
comparative activity of deet and ai3-37220 repellents against the ticks ixodes scapularis and amblyomma americanum (acari: ixodidae) in laboratory bioassays.the repellents n,n-diethyl-3-methylbenzamide (deet) and racemic 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (ai3-37220) were evaluated using two different laboratory bioassays to determine their relative effectiveness against host-seeking nymphs of the blacklegged tick, ixodes scapularis say, and the lone star tick, amblyomma americanum (l.). in a petri dish bioassay, ticks were released within a ring of repellent on a horizontal filter paper disk. in the second bioassay, ticks were allowed ...200415061285
two feeding-induced proteins from the male gonad trigger engorgement of the female tick amblyomma hebraeum.most female ixodid ticks, once mated, feed to repletion within 6-10 days. previous studies indicate that an engorgement factor (ef), passed to the female during copulation, may be the stimulus for engorgement. here, we show that extracts of the testis/vas deferens of fed (but not unfed) male amblyomma hebraeum contain ef bioactivity when injected into the hemocoel of feeding virgins. we have produced recombinant proteins (recproteins) from 28 feeding-induced genes in the male gonad and have iden ...200415069191
a monitoring study on the prevalence of dermatophilosis and parafilariosis in cattle in a smallholder semi-arid farming area in zimbabwe.the prevalences of dermatophilosis and parafilariosis were monitored for one year in cattle in sanyati, a semi-arid smallholder farming area in zimbabwe. the prevalence of dermatophilosis differed (p < 0.05) with season and among calves, cows, oxen and bulls. in bulls and cows, dermatophilosis lesions were localized mainly to the inguinal regions and between the front limbs. the prevalence and morbidity of dermatophilosis infection were significantly higher (p < 0.05) during the wet season than ...200415080537
species of ticks on camels and their seasonal population dynamics in eastern ethiopia.a study was conducted to identify the species of ticks found on camels (camelus dromedarius) and their seasonal population dynamics in eastern ethiopia. collection and identification of the ticks were undertaken at 2-month intervals from december 1997 to august 1999. on each occasion, all the visible adult ticks were collected from one side of the body of each of the same 17 camels. the most abundant species of ticks on the camels were rhipiephalus pulchellus (85.2%), hyalomma dromedarii (5.9%), ...200415080539
detection of pathogenic ehrlichia in ticks collected at acquisition sites of human ehrlichiosis in missouri.we collected 385 ticks from sites in missouri associated with human monocytic ehrlichiosis. using pcr, we detected e. chaffeensis or e. ewingii in 2 of 19 pools of adult amblyomma americanum, 0 of 32 pools of dermacentor variabilis, and 6 (18%) of 39 pools of unspeciated nymphal ticks from 3 of 6 sites associated with disease and one site not associated with disease. we also detected a variant of a. phagocytophila in one nymph pool.200415119113
the distribution and ecological 'preferences' of the tick amblyomma cajennense (acari: ixodidae), an ectoparasite of humans and other mammals in the americas.the distribution and ecological 'preferences', in the nearctic and neotropical regions, of the prominent, pathogen-carrying tick amblyomma cajennense (fabricius) were reviewed, on the basis of the published literature, satellite imagery, and the examination of several tick collections. the tick has been collected from the southern u.s.a. (texas and florida) to northern argentina, but is probably absent from uruguay and southern brazil (the few records of the species in these areas probably repre ...200415119974
glycerophosphodiester phosphodiesterase gene (glpq) of borrelia lonestari identified as a target for differentiating borrelia species associated with hard ticks (acari:ixodidae).a glpq ortholog was identified in dna from borrelia lonestari-positive amblyomma americanum, providing further evidence that b. lonestari is more closely related to the relapsing fever group spirochetes than to borreliae that cause lyme disease. this finding provides a basis for developing diagnostic assays to differentiate species of borrelia transmitted by hard ticks.200415131225
disease survey of free-ranging grey brocket deer (mazama gouazoubira) in the gran chaco, bolivia.samples from 17 free-ranging hunter-killed grey brocket deer (mazama gouazoubira) in the gran chaco, bolivia, were collected during june-august 1999. all 17 deer appeared to be in good condition at the time of death. gross necropsies were performed, serum was collected for serologic evaluation of selected infectious disease agents, and feces and ectoparasites were collected for evaluation of internal and external parasites. serologic tests were positive for antibodies against bovine respiratory ...200415137493
monthly dynamics of ticks (acari:ixodida) infesting n'dama cattle in the republic of guinea.the occurrence of ixodid ticks on n'dama cattle was studied in the republic of guinea between june 1994 and may 1995. monthly tick collections were performed on 80 animals from 14 villages located in dabola, kouroussa and dinguiraye prefectures. a total of 19,804 ticks was collected and classified using standard taxonomic keys. the following tick species were identified: amblyomma variegatum, hyalomma marginatum rufipes, hyalomma trunctum, hyalomma nitidum, rhipicephalus lunulatus, rhipicephalus ...200415139086
life cycle of amblyomma cooperi (acari: ixodidae) using capybaras (hydrochaeris hydrochaeris) as hosts.the life cycle of amblyomma cooperi was evaluated under laboratory conditions testing different host species. larval infestations were performed on chickens (gallus gallus) and capybaras (hydrochaeris hydrochaeris). nymphal infestations were performed on g. gallus, h. hydrochaeris, guinea pigs (cavia porcellus) and wild mice (calomys callosus). infestations by adult ticks were performed only on capybaras. all free-living stages were observed in darkness at 27 degrees c and rh 85%. capybaras were ...200415139274
ehrlichia ruminantium seroprevalence in domestic ruminants in ghana; i. longitudinal survey in the greater accra region.serum samples collected monthly over a 34-month period from cattle, sheep and goats in the greater accra region of ghana were tested for antibodies to ehrlichia (previously cowdria) ruminantium, the causative agent of heartwater, by polyclonal competitive elisa (pc-elisa). maternal antibodies, detected in about half of animals followed from under 1 month old, declined to negative levels within 2-4 months. amblyomma variegatum tick vectors were present on livestock in rural areas throughout the y ...200415145496
rickettsia species infecting amblyomma cooperi ticks from an area in the state of são paulo, brazil, where brazilian spotted fever is endemic.owing to the potential role of the tick amblyomma cooperi in the enzootic cycle of rickettsia rickettsii, the etiologic agent of brazilian spotted fever (bsf), this study evaluated infection by rickettsia species in a. cooperi ticks collected from an area in brazil where bsf is endemic. among a total of 40 a. cooperi adult ticks collected in an area of bsf endemicity in the state of são paulo, pcr analysis detected dna of rickettsia bellii in 16 ticks (40%), and 3 other ticks (7.5%) were positiv ...200414715737
evaluation of immunocompetent and immunocompromised mice (mus musculus) for infection with ehrlichia chaffeensis and transmission to amblyomma americanum ticks.experiments on the natural history of ehrlichia chaffeensis, the agent of human monocytic ehrlichiosis (hme), would be facilitated by the availability of a laboratory animal model for transmission to vector ticks. five strains of mice were evaluated for their susceptibility to infection with e. chaffeensis and transmission competence: c57bl/6 mice, inducible nitric oxide synthase (inos) deficient mice, mhc i deficient (beta2m /) mice, mhc ii deficient mice (abb /), and b and t cell deficient (ra ...200415671738
lack of susceptibility of guinea pigs and gerbils to experimental infection with ehrlichia chaffeensis.guinea pigs and mongolian gerbils were experimentally infected with ehrlichia chaffeensis (st. vincent strain, 10 passages in vitro). the infection was monitored by serial blood sampling for pcr and by xenodiagnosis with amblyomma americanum larvae. exposure to the pathogen was confirmed using serology. neither guinea pigs nor gerbils were susceptible to infection with e. chaffeensis, and ticks fed upon these animals did not become infected with the pathogen.200415682515
molecular differentiation of metastriate tick immatures.hard ticks, family ixodidae, are divided into two groups, the metastriata and the prostriata, based on morphological differences. in the united states, there are four medically important genera of the ixodidae: ixodes, amblyomma, dermacentor, and rhipicephalus. ixodes is the only genus in and representative of the prostriata, whereas the latter three genera are members of the metastriata. all developmental stages of the prostriata can be easily differentiated from the metastriata using morpholog ...200415682516
preliminary survey of ticks (acari: ixodidae) on cattle in northern a cross sectional survey conducted during the period june 2001 to july 2002, the geographical distribution of ticks on cattle in the sudan was determined. seventeen locations were surveyed from northern, central, eastern, western, blue nile and white nile provinces. total body collections of ticks were made from 20 cattle at each location. four tick genera and 11 species were identified. the tick species collected included amblyomma lepidum, amblyomma variegatum, boophilus decoloratus, hyalom ...200415732459
an opioid peptide from synganglia of the tick, amblyomma opioid peptide, which shares similarity with mammalian hemorphins, has been identified from the synganglia (central nervous system) of the hard tick, amblyomma testindiarium. its primary sequence was established as lvvypwtkm that contains a tetrapeptide sequence tyr-pro-trp-thr of hemorphin-like opioid peptides. by hot-plate bioassay, the purified peptide and synthetic peptide displayed dose-related antinociceptive effect in mice, as observed for other hemorphin-like opioid peptides. this is ...200415752574
systematics and evolution of ticks with a list of valid genus and species recent years there has been much progress in our understanding of the phylogeny and evolution of ticks, in particular the hard ticks (ixodidae). indeed, a consensus about the phylogeny of the hard ticks has emerged which is quite different to the working hypothesis of 10 years ago. so that the classification reflects our knowledge of ticks, several changes to the nomenclature of ticks are imminent or have been made. one subfamily, the hyalomminae, should be sunk, while another, the bothriocro ...200415938503
tick-borne least 38 viral species are transmitted by ticks. virus-tick-vertebrate host relationships are highly specific and less than 10% of all tick species (argasidae and ixodidae) are known to play a role as vectors of arboviruses. however, a few tick species transmit several (e.g. ixodes ricinus, amblyomma variegatum) or many (i. uriae) tick-borne viruses. tick-borne viruses are found in six different virus families (asfarviridae, reoviridae, rhabdoviridae, orthomyxoviridae, bunyaviridae, flaviviri ...200415938513
influence of meso- and microscale habitat structure on focal distribution of sympatric ixodes scapularis and amblyomma americanum (acari: ixodidae).we compared the distribution of sympatric ixodes scapularis say and amblyomma americanum (l.) within several suitable forested habitats at different spatial scales and characterized differences in microhabitat features accounting for the observed distribution of questing ticks. we used automatic data loggers placed in the shrub and litter layers to contrast mesoclimate and microclimate conditions experienced by questing ticks. larger numbers of i. scapularis were collected at sites where the for ...200515962776
the fc fragment mediates the uptake of immunoglobulin c from the midgut to hemolymph in the ixodid tick amblyomma americanum (acari: ixodidae).the phenomenon of immunoglobulin uptake from the midgut into the hemolymph has been observed in both argasid and ixodid ticks, but the mechanism of the uptake is not known. using capillary feeding of adult amblyomma americanum (l.) female ticks, we investigated the role of immunoglobulin g fc and fab fragments in the uptake process. intact igg and fragments labeled with 125i were introduced alone or as a mixture with a 10-fold molar excess of unlabeled compounds into ticks, and then the concentr ...200515962788
relative encounter frequencies and prevalence of selected borrelia, ehrlichia, and anaplasma infections in amblyomma americanum and ixodes scapularis (acari: ixodidae) ticks from central new evaluate their relative importance in tick-borne disease transmission in new jersey, host-seeking amblyomma americanum (l.) and ixodes scapularis say adults and nymphs were collected during spring activity periods in 2003 and 2004 to determine relative frequencies at which these ticks were encountered from an area known to be hyperendemic for lyme disease. although similar numbers of the two species were encountered during early spring of both years, a. americanum were encountered more often ...200515962799
reptile trade and the risk of exotic tick introductions into southern south american countries.ticks exotic for the neotropical region were found on python regius imported into argentina and chile. all ticks (7 males and 3 females) were classified as amblyomma latum koch, 1844 ( = aponomma latum). additionally, four lots comprising 18 males of the argentinean tortoise tick, amblyomma argentinae neumann, 1904, were found on a terrestrial tortoise, chelonoidis chilensis, and on three terrestrial tortoises (probably c. chilensis) imported to uruguay presumably from argentina). these findings ...200515969465
redescription of amblyomma fuscum neumann, 1907 (acari: ixodidae), a rare south america tick confirmed in brazil.the species amblyomma fuscum neumann, 1907 is a rare tick found on the neotropical region, but it has not been recorded as a valid taxon in some lists proposed by current taxonomists. after a comparison between the brazilian material of a. fuscum deposited in the acari collection of the butantan institute, são paulo, brazil, and the male type deposited in leiden museum of natural history, the netherlands, we confirm the taxonomic validity of a. fuscum and redescribe the adult specimens based on ...200515980961
effects of combining the fungi beauveria bassiana and metarhizium anisopliae on the mortality of the tick amblyomma variegatum (ixodidae) in relation to seasonal changes.the effect of formulation, fungal concentration, type and seasonal changes on the mortality of the tick amblyomma variegatum was investigated. a previous study demonstrated high pathogenicity of strains of the fungi beauveria bassiana and metarhizium anisopliae against the ticks rhipicephalus appendiculatus and amblyomma variegatum (kaaya et al. j invertebr pathol 1996; 67: 15-20). the present study was undertaken to explore possible additive or synergistic effects of the two fungi on a. variega ...200515983739
sequence variation of the ribosomal dna second internal transcribed spacer region in two spatially-distinct populations of amblyomma americanum (l.) (acari: ixodidae).sequence analysis of the ribosomal dna second internal transcribed spacer (its 2) region in 2 spatially distinct populations of amblyomma americanum (l.) revealed intraspecific variation. nucleotide sequences from multiple dna extractions and several polymerase chain reaction amplifications of eggs from mixed-parentage samples from both populations of ticks revealed that 12 of 1,145 (1.0%) sites varied. three of the 12 sites of variation were distinct between the 2 a. americanum populations, whi ...200515986597
polymerase chain reaction detection of cytauxzoon felis from field-collected ticks and sequence analysis of the small subunit and internal transcribed spacer 1 region of the ribosomal rna gene.cytauxzoon felis produces a disease in domestic cats in the midwest (u.s.a.), which often leads to a fatal outcome. although the clinical disease process is well described, there are still many unanswered questions about this organism. for example, it is unknown whether species of ticks other than dermacentor variabilis can serve as vectors for transmission. with recent reports of surviving cats from limited geographic areas, another relevant question is the potential for genetically less virule ...200515986625
feeding predilection of gulf coast tick, amblyomma maculatum koch, nymphs on cattle.gulf coast tick nymphs successfully attached and fed on cattle after being freely released. six hereford heifers were each infested with approximately 2000 gulf coast tick nymphs, three with a strain originating from refugio co., tx, and three with ticks from osage co., ks by free release on the head and legs to simulate field acquisition of questing nymphs. two re-infestations were conducted, the first at 7 days and the second at 28 days. nymph dispersal was estimated by daily inspection of 22 ...200515993001
repellent efficacy of four commercial deet lotions against amblyomma hebraeum (acari: ixodidae), the principal vector of rickettsia africae in southern africa.african tick bite fever, caused by rickettsia africae, is an emerging zoonotic infection in rural sub-saharan africa and the french west indies. we tested the repellent efficacy of four commercial diethyl-3-methylbenzamide (deet) lotions against amblyomma hebraeum koch, the principal vector of r. africae in southern africa, by using a human bioassay in which repellent-treated fingers were presented to questing tick nymphs hourly for 4h. three lotions with 19.5, 31.6 and 80% deet concentrations, ...200515993907
transcription analysis of the major antigenic protein 1 multigene family of three in vitro-cultured ehrlichia ruminantium isolates.ehrlichia ruminantium, an obligate intracellular bacterium transmitted by ticks of the genus amblyomma, causes heartwater disease in ruminants. the gene coding for the major antigenic protein map1 is part of a multigene family consisting of a cluster containing 16 paralogs. in the search for differentially regulated genes between e. ruminantium grown in endothelial and tick cell lines that could be used in vaccine development and to determine if differences in the map1 gene cluster exist between ...200515995193
possible tick-borne human enterovirus resulting in aseptic meningitis.enterovirus-specific genetic sequences were isolated from two amblyomma americanum tick pools. identical genetic sequences were later obtained from cerebrospinal fluid of a patient with aseptic meningitis and a recent history of tick attachment. these observations suggest the possibility of an emerging tick-borne human enterovirus associated with aseptic meningitis.200516000481
rapid detection methods and prevalence estimation for borrelia lonestari glpq in amblyomma americanum (acari: ixodidae) pools of unequal size.dna was extracted from pools of amblyomma americanum ticks collected from vegetation at two sites in fort leonard wood, missouri and tested for the presence of borrelia spp. two new methods were developed to detect borrelia lonestari dna by targeting the glycerophosphodiester phosphodiesterase (glpq) gene. the first method detected b. lonestari dna using a sybr green i melting curve analysis of the pcr product obtained with glpq gene primers. the second method, a glpq taqman assay, detected and ...200516011431
detection of ehrlichia spp. in raccoons (procyon lotor) from georgia.raccoons (procyonis lotor) and opossums (didelphis virginianus) acquired from six contiguous counties in the piedmont physiographic region of georgia were investigated for their potential role in the epidemiology of ehrlichial and anaplasmal species. serum was tested by indirect fluorescent antibody (ifa) assay for the presence of antibodies reactive to ehrlichia chaffeensis, e. canis, and anaplasma phagocytophilum (hga agent). nested polymerase chain reaction (pcr) assay was used to test whole ...200516011433
identification of candidate sialome components expressed in ixodid tick salivary glands using secretion signal complementation in mammalian cells.ixodid ticks manipulate mammalian host pathways by secreting molecules from salivary glands. novel cdnas containing functional secretion signals were isolated from ixodid tick salivary glands using a signal sequence trap. only 15/61 rhipicephalus appendiculatus and 1/7 amblyomma variegatum cdnas had significant identity (< 1e-15) to previously identified sequences. polypeptides that may interact with host pathways included a kinase inhibitor. two proteins encoded homologues of the yolk protein v ...200516033433
rnai-mediated gene silencing to assess the role of synaptobrevin and cystatin in tick blood addition to being the conduit for pathogens into hosts, tick saliva contains a broad array of secretory products that facilitate prolonged tick attachment and blood feeding. proteins found in tick saliva modulate host hemostasis and immune responses. however, it is not clear whether ticks manipulate the immune responses of their hosts by disrupting the antigen-processing pathways of the hosts. protein secretion into tick saliva from the salivary glands is due to exocytosis of vesicular membra ...200516040003
diagnosis of hepatozoon spp. in amblyomma ovale and its experimental transmission in domestic dogs in brazil.transmission of hepatozoon spp. to dogs was investigated using four species of ixodid ticks: rhipicephalus sanguineus, amblyomma aureolatum, amblyomma ovale and amblyomma cajennense. we collected completely or partially engorged adult ticks of these species from dogs that were naturally infested and positive for hepatozoon spp. we selected some of these ixodids and inoculated them orally in four negative dogs. the other ticks were dissected and examined for oocysts. of all dogs inoculated orally ...200516081219
ticks (acari: ixodida) on wild carnivores in brazil.the present study reports field data of ticks infesting wild carnivores captured from july 1998 to september 2004 in brazil. additional data were obtained from one tick collection and from previous published data of ticks on carnivores in brazil. during field work, a total of 3437 ticks were collected from 89 cerdocyon thous (crab-eating fox), 58 chrysocyon brachyurus (maned wolf), 30 puma concolor (puma), 26 panthera onca (jaguar), 12 procyon cancrivorus (crab-eating raccoon), 4 speothos venati ...200516082932
amblyomma latepunctatum, a valid tick species (acari: ixodidae) long misidentified with both amblyomma incisum and amblyomma 2000, we initiated an investigation on the tick fauna of rondônia state, where we collected many specimens of amblyomma scalpturatum neumann, 1906 and amblyomma incisum neumann, 1906. in addition, we also collected a third group of ticks that were morphologically closely related to those 2 species, but sufficiently different to be considered a distinct species; members of this group were subsequently identified as amblyomma latepunctatum tonelli-rondelli, 1939, through comparison with the typ ...200516108543
drop off rhythm and survival periods of amblyomma lepidum (acari: ixodidae) under field this study, engorged amblyomma lepidum ticks were found to drop off in two peaks, one in the morning and one in the evening. most larvae and females engorged during the morning hours between 06.00 h and 10.00 h with a peak around 08.00 h, whereas the majority of the nymphs dropped in the evening between 18.00 h and 24.00 h with the peak around 22.00 h. although the effect of time on drop-off patterns of the ticks was statistically significant (p< or = 0.001), there were no significant seasona ...200516132736
a collection of ticks (ixodidae) from wild birds in uruguay.thirty nine wild birds from seven families (alcedinidae, emberizidae, furnariidae, parulidae, trochilidae, turdidae and tyrannidae) were caught from 4 to 7 of february, 2004 at rincón da vassoura (31 degrees 15' s 56 degrees 03' w) department of tacuarembó, uruguay. ninety one nymphs and forty one larvae of ixodidae were recovered from them. the majority of ticks were conventionally identified but 16s mitochondrial rdna sequences were obtained for larvae and nymphs of amblyomma with uncertain sp ...200516132744
ticks parasitizing reptiles in the bahamas.two species of reptile ticks, amblyomma dissimile koch and amblyomma torrei pérez vigueras (acari: ixodidae), are reported from the bahama islands for the first time. the widespread neotropical (including the caribbean and southern florida) a. dissimile was recovered on andros island from three species of reptiles all for the first time: the andros iguana cyclura cychlura cychlura cuvier, the andros curly tail lizard leiocephalus carinatus coryi schmidt, and the andros boa epicrates striatus fow ...200516134982
amblyomma tigrinum (acari: ixodidae): new data on hosts and biology of immature stages and on dna composition.biological data of immature stages of amblyomma tigrinum were obtained from larvae and nymphs both fed on rats and rabbits. data from nymphs recovered from a wild rodent (galea musteloides) are also reported. additional results in dna composition of males moulted from nymphs fed on laboratory and wild hosts are presented. the ticks were maintained in darkness at 27 +/- 1 degrees c and 83-86% rh. the mean recovery rates were 49.1% and 43.6% with a moulting success of 96.2% and 90.8% in larvae fed ...200516143451
description of the larva of amblyomma longirostre (koch,1844)(acari: ixodidae) by light and scanning electron microscopy.the description of the larva of amblyomma longirostre (koch, 1844) is based on optical and scanning electron microscopy. larvae (f1) were obtained under laboratory conditions from an engorged a. longirostre female, which had been collected on a coendu prehensilis (linnaeus) (rodentia: erethizontidae) from the jaraguá mountain, são paulo municipality, state of são paulo, brazil. several characters are presented including the chaetotaxy of idiosoma, palps and haller's organ, campaniform sensillum ...200516153345
[the effect of immersion in distilled water on the engorged larvae and nymphs of amblyomma cajennense (fabricius,1787)(acari: ixodidae)].to evaluate the effect of the immersion of engorged larvae and nymphs of amblyomma cajennense, these stages were immersed by 24, 48, 72 and 96 hours in test tubes containing distilled water. the period of premolt of the nymphs increased proportionally to the time of immersion (p<0.05). the ecdisis period, the longevity and the mortality (days) were similar in all of treatments (p>0.05). the percentage of ecdisis in nymphs was reduced after 72 hours of immersion of the larvae (p<0.05). none of th ...200516153347
hemorrhagic disease in dogs infected with an unclassified intraendothelial piroplasm in southern brazil.a hemorrhagic disease affecting dogs in brazil, referred to popularly as "nambiuvú" (bloody ears) and believed to be transmitted by ticks, has been observed in animals infected with an organism described originally in 1910 as a piroplasm, and known locally as rangelia vitalii. in this series of 10 cases, the disease was characterized by anaemia, jaundice, fever, spleno- and lymphadenomegaly, hemorrhage in the gastrointestinal tract, and persistent bleeding from the nose, oral cavity and tips, ma ...200516153781
ehrlichial infection in cameroonian canines by ehrlichia canis and ehrlichia ewingii.ehrlichia chaffeensis and ehrlichia ewingii are agents of emerging human ehrlichioses in north america and are transmitted primarily by amblyomma americanum ticks, while ehrlichia canis is the globally distributed cause of canine monocytic ehrlichiosis (cme) and is transmitted by the brown dog tick, rhipicephalus sanguineus. although e. canis and ehrlichia ruminantium are endemic in africa, the presence of ehrlichial agents in dogs and ticks in cameroon has not been investigated. the objective o ...200516181750
geographic distribution of ticks (acari: ixodidae) in iowa with emphasis on ixodes scapularis and their infection with borrelia iowa, public concern regarding lyme disease has increased markedly over the last decade. in response to these concerns, a statewide surveillance program was initiated in 1990 based on ticks received by the department of entomology at iowa state university. ticks were received from health care professionals, state government agencies, and the general public. a total of 5,343 ticks from all 99 iowa counties were identified during the 12 years of this study. dermacentor variabilis was the most n ...200516187889
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