Publications

antigenic classification of rickettsia felis by using monoclonal and polyclonal antibodies.	rickettsia felis is a flea-transmitted rickettsia. there is a discrepancy between its reported phylogenic and phenotypic identifications. following the first report of r. felis, it was considered by tests with serologic reagents to be closely related to another recognized flea-transmitted rickettia, r. typhi. subsequently, it appeared to be more closely related to spotted fever group (sfg) rickettsiae by genetic analysis. in the present work, r. felis was studied by microimmunofluorescence (mif) ...	2003	12626446
efficacy of three dose volumes of topically applied 65% permethrin against ctenocephalides felis and rhipicephalus sanguineus on dogs weighing 30 kg or more.	twenty-five dogs were evenly and randomly allocated by weight to five treatment groups: untreated control, 2 ml 65% permethrin (dogs weighing 15 to 29 kg, "average dogs"), and 2, 3, or 4 ml 65% permethrin (dogs weighing > or = 30 kg, "big dogs"). each dog was infested with 125 unfed, adult cat fleas, ctenocephalides felis, and 50 unfed, adult brown dog ticks, rhipicephalus sanguineus, on days -3 (ticks only), -2 (fleas only), 3, 7, 14, 17, 21, 24, and 28. fleas and ticks were counted 1 and 3 or ...	2002	12584681
assay of fipronil efficacy to prevent canine monocytic ehrlichiosis in endemic areas.	our objective was to evaluate the efficacy of fipronil for the prevention of ehrlichia canis transmission to dogs by rhipicephalus sanguineus in two endemic areas situated in africa (dakar and djibouti). we carried out controlled trials in kennels for 1 year on 248 dogs, mainly police dogs and military working dogs. eight groups were studied in a multi-centre study. fifty five fipronil treated dogs were located in two separated kennels (g3, 37 dogs in djibouti and g8, 18 dogs in dakar). g1 (66 d ...	2003	12581587
effects of salivary gland extract from rhipicephalus sanguineus on igg subclass production and cytokine mrna expression in mononuclear cells of canine peripheral blood.	the effects of salivary gland extract (sge) from r. sanguineus were examined on the production of igg1 and igg2 and the mrna expression of ifn-gamma, il-2, il-4, il-5 and il-10 in the mononuclear cells from canine peripheral blood, treated with concanavalin a (cona) in vitro. sge suppressed the cona-induced production of igg2. it also inhibited the expression of ifn-gamma, il-2 and il-5 mrna in a dose-dependent manner. no dose-dependent suppression was observed of il-10 mrna expression although ...	2003	12576721
transcriptional analysis of p30 major outer membrane protein genes of ehrlichia canis in naturally infected ticks and sequence analysis of p30-10 of e canis from diverse geographic regions.	rhipicephalus sanguineus ticks transmit ehrlichia canis, the etiologic agent of canine ehrlichiosis. in experimentally infected ticks, only p30-10 transcript was detected among 22 p30 paralogs encoding immunodominant major outer membrane p30 proteins of e. canis. the present study revealed transcription of p30-10 by e. canis in naturally infected ticks and sequence conservation of p30-10 genes for e. canis from diverse geographic regions.	2003	12574308
genital system structure of unfed female rhipicephalus (rhipicephalus) sanguineus (latreille) (ixodoidea: ixodidae).	the reproductive system of female rhipicephalus sanguineus consists of a single ovary, paired oviducts fusing into a single common oviduct, connecting tube, the vagina that in turn divides into cervical and vestibular regions, a wide receptaculum seminis and tubular accessory glands that open into the vagina between the cervical and vestibular regions. the histological structure of each part of the female reproductive system is described. the fine structure of the ovary, connecting tube and acce ...	2001	12557929
fine structure of the synganglion of unfed female rhipicephalus (rhipicephalus) sanguineus (latreille) (ixodoidea: ixodidae).	the synganglion of unfed female rhipicephalus (rhipicephalus) sanguineus (latreille) is enclosed within a well defined neural lamella underlined by the perineurium. no organelles were observed in the neural lamella, whereas axons containing neurosecretory vesicles, tracheal elements and glycogen deposits are visible in the perineurium. below the perineurium, a cortical layer of nervous and non-nervous elements surrounds an inner neuropile, the latter is enclosed by a thin subperineurial layer. t ...	2001	12557924
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 ...	2003	12525424
genetic variability within borrelia burgdorferi sensu lato genospecies established by pcr-single-strand conformation polymorphism analysis of the rrfa-rrlb intergenic spacer in ixodes ricinus ticks from the czech republic.	in europe the borrelia burgdorferi sensu lato complex is represented by five distinct genospecies: borrelia burgdorferi sensu stricto, borrelia afzelii, borrelia garinii, borrelia valaisiana, and borrelia lusitaniae. these taxonomic entities are known to differ in their specific associations with vertebrate hosts and to provoke distinct clinical manifestations in human patients. however, exceptions to these rules have often been observed, indicating that strains belonging to a single genospecies ...	2003	12514035
naturally occurring ehrlichia chaffeensis infection in two prosimian primate species: ring-tailed lemurs (lemur catta) and ruffed lemurs (varecia variegata).	a naturally occurring infection of ehrlichia chaffeensis in lemurs is described. dna of ehrlichia chaffeensis was identified by polymerase chain reaction in peripheral blood from six of eight clinically ill lemurs. organisms were cultured from the blood of one lemur exhibiting clinical and hematologic abnormalities similar to those of humans infected with e. chaffeensis.	2002	12498671
ticks (acari: ixodidae) associated with domestic dogs in franca region, são paulo, brazil.	ticks on 140 domestic dogs from both urban and rural areas of franca region in são paulo state were identified with 102 dogs from urban areas and 38 from rural areas. of urban dogs, 27.5% were infested exclusively by rhipicephalus sanguineus ticks. of the rural dogs, 36.8% were infested with the following tick species: r. sanguineus, boophilus microplus, amblyomma ovale and a. cajennense. mixed infestations included a dog hosting a. cajennense and a. ovale and another with b. microplus and r. sa ...	2001	12455880
efficacy of two 65 % permethrin spot-on formulations against canine infestations of ctenocephalides felis and rhipicephalus sanguineus.	the efficacy of two formulations of a topically applied 65% permethrin spot-on for dogs (defend exspot treatment for dogs, schering-plough animal health corp.) was evaluated against experimental infestations of the cat flea, ctenocephalides felis, and the brown dog tick, rhipicephalus sanguineus. thirty dogs were randomly allocated to treatment with 65 % permethrin in diethylene glycol monomethyl ether (original formulation), 65 % permethrin in propylene glycol monomethyl ether (test formulation ...	2002	12447841
prevalence of ectoparasites in a population of feral cats from north central florida during the summer.	ectoparasites are a common and important cause of skin disorders in cats. ectoparasites are capable of disease transmission and can cause life-threatening anemia in young or debilitated animals. the objective of this study was to determine the potential feline ectoparasites in domestic cats by using a cohort of feral cats from north central florida that have not received veterinary care and have no known exposure to insecticide application. a total of 200 feral cats were randomly selected for th ...	2002	12383632
development of resistance to nymphs of amblyomma cajennense ticks (acari:ixodidae) in dogs.	ticks have long been regarded as constraints to humans and domestic animals, but hosts often develop resistance to ticks after repeated infestations. the purpose of this investigation was to study the possible acquisition of immunity in domestic dogs to nymphs of a. cajennense by determining the tick alimentary performance after successive controlled infestations. mean engorged weight of nymphs was not significantly different among the three infestations; molting rate from nymph to adult ticks, ...	2002	12381587
attraction of the tropical bont tick, amblyomma variegatum, to human breath and to the breath components acetone, no and co2.	ticks are of medical and veterinary importance and employ several cues in search of a host. olfaction is one modality by which ticks locate a blood-meal and breath is the major vent of gaseous and volatile metabolites from the host that could contribute to this search. we studied the responses of a hunter tick, amblyomma variegatum, to diluted human breath and five of its components (acetone, co2, no, isoprene and nh3) while walking in an air stream on a locomotion compensator. diluted breath el ...	2002	12216862
an epidemiological study on ovine babesiosis in the mashhad suburb area, province of khorasan, iran.	the prevalence of babesia spp. infection was studied in sheep of the mashhad area in iran from 1998 to 2000. a total of 677 sheep originating from 115 flocks were clinically examined and investigated for the presence of babesia spp. in appropriate blood smears and any tick species on the body of the animals. the study revealed that the infection rate for babesia ovis and babesia motasi were 167 (24.6%) and 4 (0.5%), respectively. double (mixed) infections occurred in 21 (3%) sheep. differences i ...	2002	12208039
abnormal development of rhipicephalus sanguineus (ixodidae).	three malformed rhipicephalus sanguineus specimens were noticed in a tick laboratory colony. these specimens had different degrees of twining, from an almost fused individual (with two anal pores) to a partially fused adult male, with four spiracular plates. one female was a heart-shaped specimen. with both body halves fused along a longitudinal axes, with four spiracular plates and two anal pores.	2001	12206587
detection of rickettsia prowazekii in body lice and their feces by using monoclonal antibodies.	in order to identify rickettsia prowazekii in lice, we developed a panel of 29 representative monoclonal antibodies selected from 187 positive hybridomas made by fusing splenocytes of immunized mice with sp2/0-ag14 myeloma cells. immunoblotting revealed that 15 monoclonal antibodies reacted with the lipopolysaccharide-like (lps-l) antigen and 14 reacted with the epitopes of a 120-kda protein. only typhus group rickettsiae reacted with the monoclonal antibodies against lps-l. r. felis, a recently ...	2002	12202579
gynandromorphism in amblyomma cajennense and rhipicephalus sanguineus (acari: ixodidae).	during a survey of ticks on horses in november 2000, at the university of são paulo farm in pirassununga county, são paulo, brazil, 1 gynandromorph of amblyomma cajennense was collected from a naturally infested horse. in another survey on dogs in march 2001, in the urban area of monte negro, rondônia, brazil, a gynandromorph of rhipicephalus sanguineus was collected from a naturally infested dog. both specimens are described and classified as perfect bipartite protogynanders.	2002	12197141
first detection of spotted fever group rickettsiae in ixodes ricinus from italy.	ixodes ricinus from italy were examined for the first time to detect whether rickettsiae were present. using molecular methods, we detected three different spotted fever group rickettsiae, including rickettsia helvetica. our results raise the possibility that bacteria other than r. conorii are involved in rickettsial diseases in italy.	2002	12194779
evidence of spotted fever group rickettsiae in state of rio de janeiro, brazil.	ticks were obtained from dogs from february to september of 1999 at weekly intervals, in the county of piraí, state of rio de janeiro. four hundred seventy four ixodids were taxonomically identified, 103 amblyomma cajennense, seven amblyomma ovale, 209 rhipicephalus sanguineus, and 155 amblyomma sp. an hemolymph test associated with giemsa's stain revealed two specimens in 163 ticks tested (r. sanguineus and amblyomma sp), containing rickettsia-like organisms. direct immunofluorescence verified ...	2002	12163909
modification of the food and agriculture organization larval packet test to measure amitraz-susceptibility against ixodidae.	modifications of exposure time, substrate, and formulation were made to the food and agriculture organization larval packet test (lpt) to determine a combination suitable for measuring the susceptibility of boophilus microplus (canestrini) to amitraz. exposure time influenced the slope of the dose-response when paper was used as a substrate for amitraz. however, time did not influence the dose-response slope when nylon fabric was used as an amitraz substrate. formulated amitraz produced results ...	2002	12144297
transmission of hepatozoon americanum (apicomplexa: adeleorina) by ixodids (acari: ixodidae).	american canine hepatozoonosis (ach) caused by hepatozoon americanum vincent-johnson, macintire, lindsay, lenz, baneth, and shkap is an emerging, often fatal, tick-borne protozoal disease of dogs in the united states of america. dogs acquire infection by ingesting ticks that contain oocysts. to understand the invertebrate (definitive) host range of h. americanum, experiments were carried out using four ixodids, rhipicephalus sanguineus (latreille), dermacentor variabilis say, amblyomma americanu ...	2002	12144294
the dog factor in brown dog tick rhipicephalus sanguineus (acari: ixodidae) infestations in and near human dwellings.	three cases of the tick rhipicephalus sanguineus infiltration in or near human dwellings caused by dogs, and their influence on epidemiological features of human habitats have been investigated. (a) the observation of dogs kept indoors proved that single tick females could engorge and oviposit inside apartments followed by the development of subadults. (b) abundant micropopulations of ticks were formed in small yards or gardens near the dwellings where dogs lived in kennels. (c) a huge field pop ...	2002	12141741
isolation of coxiella burnetii by a centrifugation shell-vial assay from ticks collected in cyprus: detection by nested polymerase chain reaction (pcr) and by pcr-restriction fragment length polymorphism analyses.	ticks are the principal vectors and reservoirs of coxiella burnetii. the identification of isolates is necessary for understanding the clinical diversity of q fever in different geographic areas. this is the first report of isolation of c. burnetii from ticks by the shell-vial assay and by nested polymerase chain reaction (pcr) assay for the detection of this pathogen in ticks. of 141 ticks collected in cyprus (rhipicephalus sanguineus and hyalloma spp.), 10% were found to be infected with c. bu ...	2002	12135275
the omp-1 major outer membrane multigene family of ehrlichia chaffeensis is differentially expressed in canine and tick hosts.	sixteen of 22 omp-1 paralogs encoding 28-kda-range immunodominant outer membrane proteins of ehrlichia chaffeensis were transcribed in blood monocytes of dogs throughout a 56-day infection period. only one paralog was transcribed by e. chaffeensis in three developmental stages of amblyomma americanum ticks before or after e. chaffeensis transmission to naïve dogs.	2002	12117987
ehrlichia ewingii infection in white-tailed deer (odocoileus virginianus).	two closely related zoonotic ehrlichiae, ehrlichia chaffeensis and e. ewingii, are transmitted by amblyomma americanum, the lone star tick. because white-tailed deer (odocoileus virginianus) are critical hosts for all mobile stages of a. americanum and are important vertebrate reservoirs of e. chaffeensis, we investigated whether deer may be infected with e. ewingii, a cause of granulocytotropic ehrlichiosis in humans and dogs. to test for e. ewingii infection, we used polymerase chain reaction ...	2002	12095432
[complications of mediterranean spotted fever].	mediterranean spotted fever is an infectious disease due to rickettsia conori transmitted to man by the dog tick rhipicephalus sanguineus. the review of a consecutive series of 525 cases, admitted to caltagirone hospital in the last 20 years, permits the classic clinical picture to be identified by fever, maculopapular eruption and tache noire, and any complications to be visualized. usually the course of the disease is good, but 12.7% of our cases reported complications such as renal failure, m ...	2001	12087217
study on immunobiology in ectoparasites of public health interest: rhipicephalus sanguineus.	the recently defined range of mediterranean spotted fever (msf) in sardinia coincides with that of the widely studied rickettsia conorii vector, the brown dog tick rhipicephalus sanguineus. this tick is major vector of disease in humans, domestic and wild animals. characteristic features of the vector with respect to their seasonal activity, abundance as well as incidence of human-tick contact and how these factors influence the incidence of msf were studied. this paper also looks at host, patho ...	2001	12078475
genetic identification of rickettsiae isolated from ticks in japan.	following the description in japan of japanese spotted fever, caused by rickettsia japonica, a search for the vector of this disease led to the isolation of several rickettsiae from various tick species. sixty-three rickettsial isolates were obtained from six different tick species, and six type strains were described by pcr and monoclonal antibody testing. we identified these six strains by amplification and sequencing of the genes encoding 16s rrna and citrate synthase. we confirmed that the i ...	2002	12037083
diversity, seasonality and sites of attachment of adult ixodid ticks on dogs in the central region of the free state province, south africa.	several surveys of ticks infesting dogs belonging to owners in resource-limited and more affluent communities have been conducted in south africa, but no such investigation has been carried out in the free state province of this country. the present study was initiated to meet this shortcoming. ticks were collected from dogs at six localities in, and to the east of the city of bloemfontein in the central region of the province. three of these localities could be classed as resource-limited and t ...	2001	12026063
ticks parasitizing dogs in northwestern georgia.	from january 1998 through september 1999, 324 dogs in three northwestern georgia counties were examined for ticks. six species of ticks were recovered. the three most commonly collected ticks were the american dog tick, dermacentor variabilis (say) (310 male male, 352 female female; prevalence, 97%; mean intensity 2.1); the brown dog tick, rhipicephalus sanguineus (latreille) (118 male male, 119 female female, 38 nymphs; prevalence, 22%; mean intensity, 3.8); and the lone star tick, amblyomma am ...	2002	11931241
importation of the brown dog or kennel tick (rhipicephalus sanguineus) into the uk.		2002	11878449
transcript heterogeneity of the p44 multigene family in a human granulocytic ehrlichiosis agent transmitted by ticks.	human granulocytic ehrlichiosis (hge) is an emerging tick-borne zoonosis caused by a strain of anaplasma phagocytophila called the hge agent, an obligatory intracellular bacterium. the agent expresses immunodominant 44-kda outer membrane proteins (p44s) encoded by a multigene family. the present study established an experimental process for transmission of the hge agent from infected mice (a reservoir model) to nymphal ixodes scapularis ticks (a biological vector) and subsequently to horses (a p ...	2002	11854198
detection of ehrlichia canis in canine carrier blood and in individual experimentally infected ticks with a p30-based pcr assay.	detection of vector-borne pathogens is necessary for investigation of their association with vertebrate and invertebrate hosts. the ability to detect ehrlichia spp. within individual experimentally infected ticks would be valuable for studies to evaluate the relative competence of different vector species and transmission scenarios. the purpose of this study was to develop a sensitive pcr assay based on oligonucleotide sequences from the unique ehrlichia canis gene, p30, to facilitate studies th ...	2002	11825969
pathogenicity of entomopathogenic fungi to different developmental stages of rhipicephalus sanguineus (acari: ixodidae).	the pathogenicity of 4 species of entomopathogenic fungi (hyphomycetes species: beauveria bassiana, metarhizium anisopliae, metarhizium flavoviride, and paecilomyces fumosoroseus) to various developmental stages of rhipicephalus sanguineus (acari: ixodidae) ticks was compared under laboratory conditions. the most virulent isolate, m. anisopliae-108, caused 92-96% mortality to unfed larvae and nymphs on day 7 postinfection (pi) and 100% mortality to unfed adults and engorged females on day 21 pi. ...	2001	11780821
survey of tick infestation and tick-borne ehrlichial infection of dogs in ishigaki island, japan.	twelve (54.5%) of 22 free-roaming dogs in ishigaki island had tick infestation identified as rhipicephalus sanguineus. there were 121 ticks recovered and consisted of 28 females, 58 males, 22 nymphs and 3 larvae. infection of dogs possibly with canine ehrlichial pathogens was examined by both indirect immunofluorescence assay and polymerase chain reaction (pcr). two dogs of the 13 examined were sero-positive for the human granulocytic ehrlichia agent, and one of two dogs was pcr positive for ehr ...	2001	11767058
aortic valve endocarditis in a dog due to bartonella clarridgeiae.	we report the first documented case of endocarditis associated with bartonella clarridgeiae in any species. b. clarridgeiae was identified as a possible etiological agent of human cat scratch disease. infective vegetative valvular aortic endocarditis was diagnosed in a 2.5-year-old male neutered boxer. historically, the dog had been diagnosed with a systolic murmur at 16 months of age and underwent balloon valvuloplasty for severe valvular aortic stenosis. six months later, the dog was brought t ...	2001	11574571
analysis of the use of fenthion via epicutaneous in dogs for rhipicephalus sanguineus control.	the action of fenthion was studied in a 15% epicutaneous formulation upon rhipicephalus sanguineus, which may transmit pathogens to men and other animals, such as ehrlichia, babesia and ricketsia. dogs were artificially infected for the trial. the fenthion bioassays were begun four months after artificial infestation. the test group, having a mean of 186 ticks per dog, received the formulation dosage according to body weight on the neck region. tick counts were performed, considering diameters > ...	2001	11562726
transcriptional analysis of p30 major outer membrane multigene family of ehrlichia canis in dogs, ticks, and cell culture at different temperatures.	ehrlichia canis, an obligatory intracellular bacterium of monocytes and macrophages, causes canine monocytic ehrlichiosis. e. canis immunodominant 30-kda major outer membrane proteins are encoded by a polymorphic multigene family consisting of more than 20 paralogs. in the present study, we analyzed the mrna expression of 14 paralogs in experimentally infected dogs and rhipicephalus sanguineus ticks by reverse transcription-pcr using gene-specific primers followed by southern blotting. eleven ou ...	2001	11553557
detection of haemoparasites in cattle by reverse line blot hybridisation with a note on the distribution of ticks in sicily.	a reverse line blot hybridisation (rlb) of 21 oligonucleotides with polymerase chain reaction (pcr) amplified regions of 16s rrna (ehrlichia/anaplasma group) or 18s rrna (babesia/theileria group) genes of haemoparasites detected theileria annulata, t. buffeli/orientalis, babesia bovis, b. bigemina, b. divergens, ehrlichia bovis, anaplasma marginale, a. centrale and unknown species within the rickettsia tribe.a very high prevalence of mixed infections was detected, which indicated that animals in ...	2001	11511414
investigation of blood parasites in livestock infested with argasid and ixodid ticks in egypt.	nineteen species and subspecies of ixodid and argasid ticks, hyalomma dromedarii, h. impeltatum, h. anatolicum excavatum, h. a. anatolicum, h. truncatum, h. m. marginatum, h. m. rufipes, h. m. turanicum, boophilus annulatus, rhipicephalus sanguineus, r. turanicus, r. guilhoni, r. camicasi, amblyomma lipidum, a. marmoreum, a. vareigatum, argas persicus, a. hermanii and a. arboreus were collected from different localities in five governorates, giza, sharkia, ismailia, el beheira and sinai. hyalomm ...	2001	11478436
molecular and antigenic comparison of ehrlichia canis isolates from dogs, ticks, and a human in venezuela.	we previously culture isolated a strain of ehrlichia canis, the causative agent of canine ehrlichiosis, from a human in venezuela. in the present study, we examined whether dogs and ticks are infected with e. canis in venezuela and, if so, whether this is the same strain as the human isolate. pcr analysis using e. canis-specific primers revealed that 17 of the 55 dog blood samples (31%) and all three pools of four rhipicephalus sanguineus ticks each were positive. an ehrlichial agent (venezuelan ...	2001	11473993
ixodid ticks on white-tailed deer and feral swine in florida.	a state-wide survey was conducted in florida during the 1997-99 hunting seasons to examine white-tailed deer (odocoileus virginianus) and feral swine (sus scrofa) for potential indigenous vectors of the rickettsial agent of heartwater, cowdria ruminantium. a total of 504 white-tailed deer and 166 feral swine was examined from 30 wildlife management areas across the state. amblyomma maculatum, an experimental vector of c. ruminantium, was common on both deer and feral swine throughout the state. ...	2001	11469190
recombinant major antigenic protein 2 of ehrlichia canis: a potential diagnostic tool.	the major antigenic protein 2 (map2) of ehrlichia canis was cloned and expressed. the recombinant protein was characterized and tested in an enzyme-linked immunosorbent assay (elisa) format for potential application in the serodiagnosis of canine monocytic ehrlichiosis. the recombinant protein, which contained a c-terminal polyhistidine tag, had a molecular mass of approximately 26 kda. the antigen was clearly identified by western immunoblotting using antihistidine antibody and immune serum fro ...	2001	11427559
quantitative analyses of variations in the injury of endothelial cells elicited by 11 isolates of rickettsia rickettsii.	eleven isolates of spotted fever group rickettsiae from the blood of patients or ixodid ticks from north and south america were characterized. all isolates were identified as rickettsia rickettsii using restriction fragment length polymorphism analysis of a 532-bp rompa gene fragment obtained by pcr. the ability of the r. rickettsii isolates to elicit cytopathic effects and parameters of oxidative injury were examined in cultured human ea.hy 926 endothelial cells. cytopathic effects were determi ...	2001	11427428
transmission of hepatozoon canis to dogs by naturally-fed or percutaneously-injected rhipicephalus sanguineus ticks.	hepatozoon canis is an apicomplexan protozoan parasite of dogs, prevalent in asia, africa, and southern europe. experimental transmission of h. canis to dogs was performed with laboratory-reared rhipicephalus sanguineus nymphs that fed on a naturally infected dog or were percutaneously injected with canine blood containing h. canis gamonts. dogs were inoculated by oral ingestion of adult ticks containing h. canis oocysts. transstadial transmission of h. canis was recorded, whereas transovarial t ...	2001	11426725
[toxic effects and in vitro inefficacy of deltamethrin on larvae of rhipicephalus sanguineus from goiânia, goiás, brazil].	it has been observed that formulations of deltamethrin developed for disinsectization of infested places and control of parasitic arthropods of bovines and equines have frequently been used by breeders of dogs to control ticks in their animals and kennels, but without due consideration of the correct dosage or means of application. with the purpose of evaluating the efficacy of this product on rhipicephalus sanguineus, bioassays were realized with larvae at 27+/-1 degrees c, ur>80% and light per ...	2001	11391437
prevalence of vectors of the spotted fever group rickettsiae and murine typhus in a bedouin town in israel.	a survey of the vectors of spotted fever group rickettsiae and of murine typhus was carried out in rahat, a bedouin town in the negev desert, where the diseases are endemic. houses with known cases of spotted fever group rickettsiae or murine typhus were compared with those without reported clinical cases. a neighboring jewish community, lehavim, where no cases of spotted fever group rickettsiae and murine typhus were reported in recent years, was used as a control. in the houses of patients wit ...	2001	11372975
effects of salivary gland extract from rhipicephalus sanguineus on immunoglobulin class productivity of canine peripheral blood lymphocytes.	effects of salivary gland extract (sge) from rhipicephalus sanguineus on immunoglobulin class productivity of canine peripheral blood lymphocytes (pbl) in vitro were studied. the detectable limit of the elisa for canine total immunoglobulin, igm and a was at least 1, 1 and 15 ng/ml, respectively, and it seems to be useful for the evaluation of non-specific immunoglobulin class productivity in vitro. sge from r. sanguineus suppressed pokeweed mitogen- or lipopolysaccharide-induced total immunoglo ...	2001	11307936
characterization of acaricide resistance in rhipicephalus sanguineus (latreille) (acari: ixodidae) collected from the corozal army veterinary quarantine center, panama.	rhipicephalus sanguineus (latreille) were collected from the corozal army veterinary quarantine center in panama and characterized for resistance to five classes of acaricides. these ticks were highly resistant to permethrin, ddt, and coumaphos; moderately resistant to amitraz; and not resistant to fipronil when compared with susceptible strains. resistance to both permethrin and ddt may result from a mutation of the sodium channel. however, synergist studies indicate that enzyme activity is inv ...	2001	11296838
analysis of transcriptionally active gene clusters of major outer membrane protein multigene family in ehrlichia canis and e. chaffeensis.	ehrlichia canis and e. chaffeensis are tick-borne obligatory intramonocytic ehrlichiae that cause febrile systemic illness in humans and dogs, respectively. the current study analyzed the pleomorphic multigene family encoding approximately 30-kda major outer membrane proteins (omps) of e. canis and e. chaffeensis. upstream from seca and downstream of hypothetical transcriptional regulator, 22 paralogs of the omp gene family were found to be tandemly arranged except for one or two genes with oppo ...	2001	11254561
analysis of the systematic relationships among ticks of the genera rhipicephalus and boophilus (acari: ixodidae) based on mitochondrial 12s ribosomal dna gene sequences and morphological characters.	a portion of mitochondrial 12s rdna sequences (337-355 base pairs) and 63 morphological characters of 36 hard-tick species belonging to 7 genera were analyzed to determine the phylogenetic relationships among groups and species of rhipicephalus and between the genera rhipicephalus and boophilus. molecular and morphological data sets were first examined separately. the molecular data were analyzed by maximum parsimony (mp), maximum likelihood, and neighbor-joining distance methods; the morphologi ...	2001	11227901
ectoparasites of dogs belonging to people in resource-poor communities in north west province, south africa.	a total of 344 dogs belonging to people in resource-poor communities in north west province, south africa, was examined for ectoparasites, and all visible arthropods were collected from the left side of each dog. by doubling these numbers it was estimated that the dogs harboured 14,724 ixodid ticks, belonging to 6 species, 1,028 fleas, belonging to 2 species, and 26 lice. haemaphysalis leachi accounted for 420 and rhipicephalus sanguineus for 14,226 of the ticks. pure infestations of h. leachi w ...	2000	11205167
the effect of male ticks on the feeding performance of immature stages of rhipicephalus sanguineus and amblyomma americanum (acari: ixodidae).	a unique group of immunoglobulin-binding proteins (igbps), produced by ixodid male ticks during the latter half of their prolonged feeding period, improves the feeding performance of co-feeding females. as a follow-up to this observation, we investigated whether male tick feeding also affects the feeding of other developmental stages. immature stages of rhipicephalus sanguineus (latreeille) and amblyomma americanum (l.) were fed on rabbits in the presence or absence of conspecific males. the mea ...	2000	11201360
american canine hepatozoonosis. an emerging disease in the new world.	hepatozoon canis was first described from dogs in 1905 in india and rhipicephalus sanguineus was identified as the vector. dogs on the texas gulf coast were recognized in 1978 to have hepatozoonosis, and it was thought that h. canis had entered the new world. later, it was realized that american canine hepatozoonosis (ach) is more debilitating than its old world counterpart, often resulting in death. when the malady and parasite were characterized, a new species, h. americanum, was described, in ...	2000	11193705
cross reactivity between instars of the rhipicephalus sanguineus (latreille, 1806) tick.		2000	11193682
biocontrol of ticks by entomopathogenic nematodes. research update.	entomopathogenic nematodes (epns) are lethal to ticks even though they do not use their normal propagation cycle within tick cadavers. the tick boophilus annulatus was found to be far more susceptible to epns than hyalomma excavatum, rhipicephalus bursa, or rhipicephalus sanguineus. ticks seem to be less susceptible to nematodes when feeding on a host. preimaginal tick stages were less susceptible to nematodes than adult ticks. the mortality rate of unfed females was highest, followed by unfed m ...	2000	11193678
humoral immune response of dogs immunized with salivary gland, midgut, or repeated infestations with rhipicephalus sanguineus.	the antibody (ab) responses of dogs immunized with adult tick salivary gland (tsg), midgut (tmg), or repeated infestations of rhipicephalus sanguineus were monitored to determine if there is an association between ab production and r. sanguineus performance. tick-naïve dogs were immunized with tsg or tmg and subjected to two challenge infestations. the control group was infested five times at 21-day intervals. the elisa technique was used to measure ab levels in sera from these dogs, which expre ...	2000	11193634
tick salivary gland extract inhibits killing of borrelia afzelii spirochetes by mouse macrophages.	salivary gland extract (sge) from ixodes ricinus ticks inhibited the killing of borrelia afzelii spirochetes by murine macrophages. sge also reduced the production of two major defense molecules of phagocytes, superoxide and nitric oxide. it is likely that the suppression of macrophage microbicidal mechanisms contributes to the inhibitory effect of tick saliva on the killing of b. afzelii spirochetes, thus facilitating the transmission of this important pathogen.	2001	11119556
hepatozoon canis infection associated with dog ticks of rural areas of rio de janeiro state, brazil.	hepatozoon canis is a tick-borne protozoan that infects dogs and has been reported throughout the world. manifestation of h. canis infection varies from being sub-clinical in apparently healthy dogs to severe illness. the main vector of the infection is the dog tick, rhipicephalus sanguineus although other species may also transmit this agent. h. canis has been reported previously in brazil, but mostly as an occasional finding during laboratory exams and always associated with other diseases. th ...	2001	11113545
interleukin-10 modulates proinflammatory cytokines in the human monocytic cell line thp-1 stimulated with borrelia burgdorferi lipoproteins.	we determined previously that lipoproteins of borrelia burgdorferi stimulate inflammatory and anti-inflammatory cytokines (interleukin-10 [il-10]) in monocytes. il-10 could have an effect on innate and acquired immune responses to b. burgdorferi and influence the magnitude of the infectious inoculum and disease outcome. to understand the mechanism(s) of il-10 action during early infection, when innate immunity expressed chiefly by skin macrophages is key, we investigated the effect of exogenous ...	2000	11083779
epidemiology of mediterranean theileriosis in extremadura region, spain.	extremadura is an extensive region (41,000 km2) located in the southwest of spain, where animal husbandry is a very important economical resource. livestock parasitism of ticks is common in the region and it is favoured by the environmental conditions and management systems. mediterranean theileriosis (mt) is perhaps the most important tick-borne disease of cattle. although theileria annulata has been identified in extremadura since 1933, little epidemiological information is available. during t ...	1999	11071543
general review of tick species present in portugal.	at present, 24 species are known to occur in portugal: argas vespertilionis, ornithodoros maritimus and ornithodoros erraticus in argasidae; ixodes acuminatus, ixodes bivari, ixodes canisuga, ixodes frontalis, ixodes hexagonus, ixodes ricinus, ixodes simplex simplex, ixodes ventalloi, ixodes vespertilionis, dermacentor marginatus, dermacentor pictus', haemaphysalis hispanica, haemaphysalis inermis, haemaphysalis punctata, rhipicephalus bursa, rhipicephalus pusillus, rhipicephalus sanguineus, rhi ...	1999	11071535
distribution and ecology of ticks (acari: ixodidae) infesting livestock in tunisia: an overview of eighth years field collections.	ticks (ixodidae) play a significant role as vectors of pathogens of domestic animals in tunisia. the major losses caused by ticks are related to transmission of protozoan parasites. these include agents of tropical theileriosis and babesiosis in ruminants. since 1991, we conducted research studies on tick population of livestock in tunisia. this overview reports a synthesis on tick distribution, their biology and their role as vectors of pathogens in domestic animals, particularly cattle. during ...	1999	11071534
detection of ehrlichia platys dna in brown dog ticks (rhipicephalus sanguineus) in okinawa island, japan.	thirty-two rhipicephalus sanguineus females collected from eight free-roaming dogs in okinawa island, japan, were examined for ehrlichial dna by 16s rrna-based pcr and subsequent sequencing. partial sequences of ehrlichia platys 16s rrna (678 to 679 bp) were detected in three ticks (9.4%) from two dogs. this is the first report of detection of e. platys in japan, and also the first report of detection in ticks.	2000	11060094
the ixodid tick species attaching to domestic dogs and cats in great britain and ireland.	the species of ixodid ticks, attached to dogs and cats presented to veterinary practices in great britain and ireland were identified. most host animals carried only one tick species with ixodes ricinus linné (acari: ixodidae) being the most common, identified on 52% of animals, ixodes hexagonus leach (acari: ixodidae) the second most common (on 39%) and ixodes canisuga johnston (acari: ixodidae) the third most common (on 11%). a significantly higher proportion of dogs than cats carried i. ricin ...	2000	11016442
mortality rate of adult ticks due to infection by entomopathogenic nematodes.	the mortality of boophilus annulatus, hyalomma excavatum, rhipicephalus bursa, and rhipicephalus sanguineus adult ticks was recorded after their exposure in petri dishes to 5 entomopathogenic nematode strains. the strains used were dt and mexican of steinernema carpocapsae, hb hp88 of heterorhabditis bacteriophora, and is-3 and is-5 of heterorhabditis sp. the most rapid killing rates (lt50 and lt90) were observed for b. annulatus ticks (0.8-5.0 days). most unfed males died 0.3-2.8 days after the ...	2000	10958439
efficacy of selamectin against experimentally induced tick (rhipicephalus sanguineus and dermacentor variabilis) infestations on dogs.	seven controlled studies were conducted to investigate the efficacy of selamectin against weekly infestations of dogs with rhipicephalus sanguineus and dermacentor variabilis. treatments (selamectin or vehicle alone) were applied topically at weekly, 2-week, or monthly intervals or in a "monthly plus" regimen (monthly treatment with an additional treatment at 14 days after the first treatment). selamectin was supplied in unit dose tubes designed to deliver a minimum dosage of 6mgkg(-1). the stud ...	2000	10940535
performance of female rhipicephalus sanguineus (acari: ixodidae) fed on dogs exposed to multiple infestations or immunization with tick salivary gland or midgut tissues.	this investigation compared the effects of repeated infestations to immunization of dogs with tick salivary gland or midgut extracts on the feeding and fecundity performances of female rhipicephalus sanguineus (latrielle). in each immunized group, three tick-naive dogs were immunized three times with tick salivary gland or midgut extracts, and twice challenged at 21-d intervals by allowing 80 female and 40 male adult ticks to feed on each host. the repeated infestation group of three naive dogs ...	2000	10916303
a review of the ticks (acari, ixodida) of brazil, their hosts and geographic distribution - 1. the state of rio grande do sul, southern brazil.	a review of the ticks (acari, ixodida) of the state of rio grande do sul, southern brazil, was completed as a step towards a definitive list (currently indicated as 12) of such species, their hosts and distribution. the ticks: argas miniatus (poultry), ixodes loricatus (opossums), amblyomma aureolatum (dogs), a. calcaratum (anteaters), a. cooperi (capybaras), a. nodosum (anteaters), a. tigrinum (dogs) (neotropical) and rhipicephalus sanguineus (dogs) (introduced, cosmopolitan, afrotropical) were ...	2000	10904399
babesiosis.	babesiosis is an emerging, tick-transmitted, zoonotic disease caused by hematotropic parasites of the genus babesia. babesial parasites (and those of the closely related genus theileria) are some of the most ubiquitous and widespread blood parasites in the world, second only to the trypanosomes, and consequently have considerable worldwide economic, medical, and veterinary impact. the parasites are intraerythrocytic and are commonly called piroplasms due to the pear-shaped forms found within inf ...	2000	10885987
report on ticks collected in the southeast and mid-west regions of brazil: analyzing the potential transmission of tick-borne pathogens to man.	specimens of ticks were collected in 1993, 1996, 1997, and 1998, mostly from wild and domestic animals in the southeast and mid-west regions of brazil. nine species of amblyommidae were identified: anocentor nitens, amblyomma cajennense, amblyomma ovale, amblyomma fulvum, amblyomma striatum, amblyomma rotundatum, boophilus microplus, boophilus annulatus, and rhipicephalus sanguineus. the potential of these tick species as transmitters of pathogens to man was analyzed. a flaviviridade flavivirus ...	1999	10881097
tick species parasitizing people in an area endemic for tick-borne diseases in north-western italy.	in 1995 and 1996, 318 ticks were recovered from 240 people in liguria (province of savona, italy). most of the ticks (284; 89.3%) were sheep ticks, ixodes ricinus. rhipicephalus sanguineus (31; 9.8%) and dermacentor marginatus (3; 0.9%) were also recorded. all three life stages of i. ricinus were found on humans while only nymphs and adults of r. sanguineus and adults of d. marginatus were collected. human tickbites were most frequent in the municipalities of the province where roe deer density ...	1999	10870560
is the detection of anti-rhipicephalus sanguineus (rs24p) antibodies a valuable epidemiological tool of tick infestation in dogs?	antibodies against the 24 kda rhipicephalus sanguineus (rs24p) protein were detected by elisa to evaluate the relationship between antibodies and tick infestation. the mean titer of 3 dogs that underwent 2 experimental infestations with adult ticks was transiently increased after the second infestation. there was a significant difference in mean titers between positive control dogs naturally infested with ticks and tick-naive dogs. these results suggested that anti-rs24p antibodies detected by e ...	2000	10863953
effect of ivermectin on the brown dog tick, rhipicephalus sanguineus.	ivermectin (ivomec) proved to be effective in controlling r. sanguineus. all brown dog ticks infesting the treated dogs (subcutaneous injections) with 1.5 ml or 2 ml/50 kg dropped off within 4 or 3 days respectively. the dropped off ticks were completely inactive and died within one day or two. ticks exposed to filter papers impregnated with 100 micrograms/ml (66.67%) died within four days. a dose of 1.5-2 microliters/50 kg eradicated toxocara canis infection in four dogs, and caused shrinkage o ...	2000	10786024
the complete mitochondrial dna sequence of the horseshoe crab limulus polyphemus.	we determined the complete 14,985-nt sequence of the mitochondrial dna of the horseshoe crab limulus polyphemus (arthropoda: xiphosura). this mtdna encodes the 13 protein, 2 rrna, and 22 trna genes typical for metazoans. the arrangement of these genes and about half of the sequence was reported previously; however, the sequence contained a large number of errors, which are corrected here. the two strands of limulus mtdna have significantly different nucleotide compositions. the strand encoding m ...	2000	10779542
short report: isolation and identification of two spotted fever group rickettsial strains from patients in catalonia, spain.	two rickettsial strains, 16b (previously isolated) and fb1, were isolated from blood from patients with mediterranean spotted fever in catalonia, spain. these are the only 2 human rickettsial isolates of the spotted fever group obtained so far in spain. these strains were identified by the polymerase chain reaction and sequence analysis of a fragment of the outer membrane protein a (ompa) gene. the partial ompa sequence was found to be 100% identical with that of rickettsia conorii (malish 7 str ...	2000	10761740
genetic and antigenic evidence supports the separation of hepatozoon canis and hepatozoon americanum at the species level.	recognition of hepatozoon canis and hepatozoon americanum as distinct species was supported by the results of western immunoblotting of canine anti-h. canis and anti-h. americanum sera against h. canis gamonts. sequence analysis of 368 bases near the 3' end of the 18s rrna gene from each species revealed a pairwise difference of 13.59%.	2000	10699047
helminthic transmission and isolation of ehrlichia risticii, the causative agent of potomac horse fever, by using trematode stages from freshwater stream snails.	we report successful helminthic transmission of ehrlichia risticii, the causative agent of potomac horse fever, using trematode stages collected from juga yrekaensis snails. the ehrlichial agent was isolated from the blood of experimentally infected horses by culture in murine monocytic cells and identified as e. risticii ultrastructurally and by characterization of three different genes.	2000	10699046
ticks of south carolina (acari: ixodoidea).	county and host records are reported for 19 species of ticks from south carolina: amblyomma americanum, amblyomma maculatum, amblyomma tuberculatum, aponomma latum, boophilus annulatus, boophilus microplus, dermacentor albipictus, dermacentor variablis, haemaphysalis leporispalustris, ixodes affinis, ixodes brunneus, ixodes cookei, ixodes marxi, ixodes minor, ixodes scapularis, ixodes texanus, ixodes woodi, rhipicephalus sanguineus, and ornithodoros capensis. ixodes woodi is recorded from south ...	1999	10672552
sequential histopathology at the rhipicephalus sanguineus tick feeding site on dogs and guinea pigs.	the tick rhipicephalus sanguineus is a very common parasite of dogs worldwide. dogs seem unable to acquire resistance against this tick species, whereas guinea pigs demonstrate a very strong resistance following primary infestation. we studied the inflammatory reaction at the r. sanguineus tick feeding site on dogs and guinea pigs during primary and tertiary infestations at different time intervals after attachment. biopsies were collected after 4, 24, 48 and 96 hours. changes that were found in ...	1999	10668866
general properties and phylogenetic utilities of nuclear ribosomal dna and mitochondrial dna commonly used in molecular systematics.	to choose one or more appropriate molecular markers or gene regions for resolving a particular systematic question among the organisms at a certain categorical level is still a very difficult process. the primary goal of this review, therefore, is to provide a theoretical information in choosing one or more molecular markers or gene regions by illustrating general properties and phylogenetic utilities of nuclear ribosomal dna (rdna) and mitochondrial dna (mtdna) that have been most commonly used ...	0	10634037
molecular cloning and characterization of the 120-kilodalton protein gene of ehrlichia canis and application of the recombinant 120-kilodalton protein for serodiagnosis of canine ehrlichiosis.	the 120-kda outer membrane protein (p120) is a potential adhesin of ehrlichia chaffeensis, and recombinant p120 is very useful for serodiagnosis of human monocytotropic ehrlichiosis. the analogous gene of p120 in ehrlichia canis was cloned, sequenced, and expressed. like the e. chaffeensis p120, the e. canis p120 contains tandem repeat units. however, neither the repeat number nor the amino acid sequences in the repeats are identical in the two ehrlichia species. the repeat units are hydrophilic ...	2000	10618118
new rickettsiae in ticks collected in territories of the former soviet union.	dermacentor nuttallii from siberia, rhipicephalus sanguineus from crimea, and rh. pumilio from the astrakhan region were infected with rickettsia sibirica (12%), r. conorii (8%), and the astrakhan fever agent (3%), respectively. three new rickettsiae of the r. massiliae genogroup were identified in ticks by 16s rdna, glta, and ompa sequencing.	1999	10603217
molecular typing of borrelia burgdorferi sensu lato: taxonomic, epidemiological, and clinical implications.	borrelia burgdorferi sensu lato, the spirochete that causes human lyme borreliosis (lb), is a genetically and phenotypically divergent species. in the past several years, various molecular approaches have been developed and used to determine the phenotypic and genetic heterogeneity within the lb-related spirochetes and their potential association with distinct clinical syndromes. these methods include serotyping, multilocus enzyme electrophoresis, dna-dna reassociation analysis, rrna gene restri ...	1999	10515907
q fever.	q fever is a zoonosis with a worldwide distribution with the exception of new zealand. the disease is caused by coxiella burnetii, a strictly intracellular, gram-negative bacterium. many species of mammals, birds, and ticks are reservoirs of c. burnetii in nature. c. burnetii infection is most often latent in animals, with persistent shedding of bacteria into the environment. however, in females intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being r ...	1999	10515901
characterization of mutations in the rpob gene in naturally rifampin-resistant rickettsia species.	rickettsiae are gram-negative, obligately intracellular bacteria responsible for arthropod-borne spotted fevers and typhus. experimental studies have delineated a cluster of naturally rifampin-resistant spotted fever group species. we sequenced the 4, 122- to 4,125-bp rna polymerase beta-subunit-encoding gene (rpob) from typhus and spotted fever group representatives and obtained partial sequences for all naturally rifampin-resistant species. a single point mutation resulting in a phenylalanine- ...	1999	10508014
comparison of methods for introducing and producing artificial infection of ixodid ticks (acari: ixodidae) with ehrlichia chaffeensis.	only 29.5 +/- 8.91% of engorged amblyomma americanum (l.) nymphs that we inoculated with ehrlichia chaffeensis molted successfully to adults compared with 75.8 +/- 7.46% of engorged nymphs that were not inoculated. however, 65.4 +/- 6.02% of unfed nymphs of this species were exposed for 2 h to e. chaffeensis suspension introduced to them through glass capillaries gained weight. these nymphs were placed on rabbits, and approximately 50% of them completed their feeding and molted successfully to a ...	1999	10467766
recent advances in determining the pathogenesis of canine monocytic ehrlichiosis.		1999	10449445
development of babesia gibsoni in the midgut of the nymphal stage of the tick, rhipicephalus sanguineus.	studies were made on the development of babesia gibsoni in the midgut of the nymphal stage of the tick, rhipicephalus sanguineus. six hr after repletion, merozoites of b. gibsoni, free of erythrocytes, were observed in the midgut contents of the ticks. after that, within 24 hr, those merozoites were transformed into ring-forms which were relatively large ring 1-2 microns in diameter. later, the ring forms developed into spherical forms which were somewhat elliptical in shape and 3-4 microns in d ...	1999	10423695
development of babesia gibsoni in the midgut of larval tick, rhipicephalus sanguineus.	studies were made on the development of babesia gibsoni in the midgut of the larval tick, rhipicephalus sanguineus. six hr after repletion, merozoites of b. gibsoni, freed from erythrocytes, were observed in the midgut contents of the tick. after that, within 24 hr, those merozoites were transformed into the ring-forms which were relatively large, 2-3 microns in diameter. later, the ring forms developed into the spherical forms which were subelliptical in shape and 4-6 microns in diameter. withi ...	1999	10423693
coinfection with multiple tick-borne pathogens in a walker hound kennel in north carolina.	both dogs and humans can be coinfected with various ehrlichia, bartonella, rickettsia, and babesia species. we investigated a kennel of sick walker hounds and their owners in southeastern north carolina for evidence of tick-borne infections and associated risk factors. a high degree of coinfection was documented in the dog population. of the 27 dogs, 26 were seroreactive to an ehrlichia sp., 16 to babesia canis, and 25 to bartonella vinsonii, and 22 seroconverted to rickettsia rickettsii antigen ...	1999	10405413
invasion and intracellular development of the human granulocytic ehrlichiosis agent in tick cell culture.	human granulocytotropic ehrlichias are tick-borne bacterial pathogens that cause an acute, life-threatening illness, human granulocytic ehrlichiosis (hge). ehrlichias within neutrophil granulocytes that invade tick bite sites are likely ingested by the vector, to be transmitted to another mammalian host during the tick's next blood meal. thus, the cycle of replication and development in the vector is prerequisite to mammalian infection, and yet these events have not been described. we report tic ...	1999	10405394
comparison of an amitraz-impregnated collar with topical administration of fipronil for prevention of experimental and natural infestations by the brown dog tick (rhipicephalus sanguineus).	to compare the efficacies of amitraz and fipronil for prevention of experimental and natural infestations of rhipicephalus sanguineus.	1999	10382021
seasonal distribution of rhipicephalus sanguineus ticks (acari: ixodidae) on dogs in an urban area of morelos, mexico.	between 1993 and 1995, we examined 1742 dogs at two veterinary clinics in cuernavaca city in mexico for the presence of rhipicephalus sanguineus ticks. the overall tick infestation prevalence was 20% and there were no significant differences (p > 0.05) between different years. the prevalence was somewhat higher in spring, summer and autumn (20% or more) than in winter (13.7%). a positive correlation (p < 0.01) was found between prevalence of ticks and rainfall in spring, summer and autumn, where ...	1999	10356770
successive tick infestations selectively promote a t-helper 2 cytokine profile in mice.	several studies have revealed that t lymphocytes and cytokines play a crucial role in determining the outcome of parasitic infections in terms of protective immunity. in this study we found that rhipicephalus sanguineus tick saliva stimulates transforming growth factor-beta (tgf-beta), and reduces interleukin-12 (il-12) secretion by cells from normal c3h/hej mice. moreover, murine lymph node cells harvested 6 days after the fourth infestation with ticks presented an 82.4% decrease in their proli ...	1999	10233725
molecular cloning of the gene for a conserved major immunoreactive 28-kilodalton protein of ehrlichia canis: a potential serodiagnostic antigen.	a gene encoding a 28-kda protein of ehrlichia canis was cloned, sequenced, and expressed, and a comparative molecular analysis with homologous genes of e. canis, cowdria ruminantium, and ehrlichia chaffeensis was performed. the complete gene has an 834-bp open reading frame encoding a protein of 278 amino acids with a predicted molecular mass of 30.5 kda. an n-terminal signal sequence was identified, suggesting that the protein undergoes posttranslational modification to a mature 27.7-kda protei ...	1999	10225842
activity of a deltamethrin shampoo against ctenocephalides felis and rhipicephalus sanguineus in dogs.	a controlled clinical trial was undertaken to assess the efficacy of an application of a 0.07% deltamethrin shampoo against fleas and ticks in dogs. twenty beagles, housed in separate cages, were randomly allocated into two groups of 10. the dogs were infested with 50 ctenocephalides felis and 50 rhipicephalus sanguineus each, and parasites were counted 24 h (fleas) and 72 h (ticks) later (day 0). dogs, when state, were then treated with 25 ml of a shampoo containing 0.07% deltamethrin (group 1) ...	1999	10206106
duration of antibodies against 24 kd protein of rhipicephalus sanguineus extract in dogs infested with the adult ticks.	a 24 kd protein from rhipicephalus sanguineus (rs24p) which was common to larvae, nymphs, male and female whole body and salivary gland extract of males and female was detected specifically in the serum from dogs after repeated infestation with adult r. sanguineus. the duration of antibodies against rs24p in dogs infested with adults was examined by western blotting analysis. anti-rs24p antibody was detected in two of 4 dogs during the period of 40 days in the first infestation. in the second in ...	1999	10081760