Publications

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molecular and parasitological survey of hepatozoon canis (apicomplexa: hepatozoidae) in dogs from rural area of sao paulo state, brazil.hepatozoon canis is a protozoan that infects dogs and is transmitted by the ingestion of the brown dog tick, rhipicephalus sanguineus. two distinct species of hepatozoon genus can infect dogs, h. canis and h. americanum. routine tests to detect the disease are based on direct examination of gametocytes on giemsa-stained blood smears. the objectives of this study were the investigation of infection prevalence in rural area dogs, the comparison of diagnostics by blood smear examination and polymer ...200818188597
canine vector-borne diseases in brazil.abstract: canine vector-borne diseases (cvbds) are highly prevalent in brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. dogs are affected by many protozoa (e.g., babesia vogeli, leishmania infantum, and trypanosoma cruzi), bacteria (e.g., anaplasma platys and ehrlichia canis), and helminths (e.g., dirofilaria immitis and dipylidium caninum) that are transmitted by a diverse range of arthropod vectors, including tick ...200818691408
[characterization of ectoparasites on dogs in the nucleus of urban expansion of juiz de fora, minas gerais, brazil].the present work studied the characterization of ectoparasites on dogs in the nucleus of urban expansion of juiz de fora, minas gerais, brazil. the collections were conducted from july to september 2003, examining 101 dogs of no defined breed. the ectoparasites were collected through visual and tactile inspection of the animals' bodies, and were then placed in bottles with 70 degrees gl ethanol and identified under a stereomicroscope. specimens were clarified and mounted on slides for analysis u ...200819265575
comparative susceptibility of larval stages of amblyomma aureolatum, amblyomma cajennense, and rhipicephalus sanguineus to infection by rickettsia rickettsii.the current study compared the susceptibility of larval stages of amblyomma cajennense (f.), amblyomma aureolatum (pallas), and rhipicephalus sanguineus (latreille) to infection by a brazilian strain of rickettsia rickettsii. guinea pigs experimentally infected by r. rickettsii were simultaneously infested by larvae of the three tick species. recovered engorged larvae were allowed to molt to nymphs and held in an incubator at 23 degrees c and 85-90% rh. subsequent flat nymphs were tested for ric ...200819058642
fungal formulations to control rhipicephalus sanguineus engorged females.entomopathogenic fungi are promising alternatives to chemical acaricides in controlling tick populations; however, biological formulations are required to improve conidial performance of these pathogens in the field. this study evaluated the effect of in vitro treatment of rhipicephalus sanguineus with conidial formulations of beauveria bassiana (bb) or metarhizium anisopliae (ma). conidia were formulated (at 10(8) conidia ml(-1)) in (1) emulsifiable concentrate (ec), (2) polymerized cellulose g ...200819120220
laboratory maintenance of rickettsia rickettsii.this unit includes protocols for the laboratory maintenance of the obligate intracellular bacterium rickettsia rickettsii, including propagation in mammalian cell cultures, as well as isolation, counting, and storage procedures. regulations for working with r. rickettsii in biosafety level 3 containment are also discussed.200819016440
a review of the off-label use of selamectin (stronghold/revolution) in dogs and cats.since its introduction approximately seven years ago, selamectin (stronghold/revolution, pfizer inc.) has been used off-label to treat a number of ecto- and endoparasite conditions in dogs and cats. it has been used as a successful prophylactic against dirofilaria repens and as a treatment for aelurostrongylus abstrusus in cats. it has also been used to treat notoedric mange, infestation with the nasal mite pneumonyssoides caninum, cheyletiella spp. and neotrombicula autumnalis infestations and ...200819032763
mediterranean spotted fever.rickettsial disease has recently undergone an important evolution, particularly in the field of molecular genetics. this development includes mediterranean spotted fever (msf), a tick-borne disease caused by rickettsia conorii. important changes have occurred in ecologic and epidemiologic comprehension of the disease, and in the occurrence of severe forms. however, many questions still remain, including the identity of the real vector and reservoir of r conorii, and whether other risk factors ex ...200818755388
questions on mediterranean spotted fever a century after its discovery.mediterranean spotted fever (msf) was first described in 1910. twenty years later, it was recognized as a rickettsial disease transmitted by the brown dog tick. in contrast to rocky mountain spotted fever (rmsf), msf was thought to be a benign disease; however, the first severe case that resulted in death was reported in france in the 1980s. we have noted important changes in the epidemiology of msf in the last 10 years, with emergence and reemergence of msf in several countries. advanced molecu ...200818760001
real-time pcr-based prevalence study, infection follow-up and molecular characterization of canine hemotropic mycoplasmas.hemotropic mycoplasmas (hemoplasmas) have been reported in several mammalian species including dogs. infections may lead to hemolytic anemia, but investigations in the dog had been hampered by the lack of adequate diagnostic methods. only recently sensitive pcr-based assays were reported for the two canine hemoplasmas, mycoplasma haemocanis and candidatus mycoplasma haematoparvum. by applying these assays, 15.4% of 460 dogs from the south of france tested hemoplasma positive. it was hypothesized ...200817656047
an insight into the sialome of the soft tick, ornithodorus parkeri.while hard ticks (ixodidae) take several days to feed on their hosts, soft ticks (argasidae) feed faster, usually taking less than 1h per meal. saliva assists in the feeding process by providing a cocktail of anti-hemostatic, anti-inflammatory and immunomodullatory compounds. saliva of hard ticks has been shown to contain several families of genes each having multiple members, while those of soft ticks are relatively unexplored. analysis of the salivary transcriptome of the soft tick ornithodoru ...200818070662
death by apoptosis in salivary glands of females of the tick rhipicephalus sanguineus (latreille, 1806) (acari: ixodidae).the salivary glands of females of the tick rhipicephalus sanguineus at three feeding stages: unfed, engorged, and at day three post-engorgement, were subjected to cytochemical methods of enzymatic analysis and cell viability. comparing glands at these stages, was observed distinct staining patterns in cells of different types of acini, specially in degenerating types iii, ii, i, which were affected in this sequence by cell death. this study also revealed changes in: nuclei, staining intensity fo ...200818346738
expression and porin activity of p28 and omp-1f during intracellular ehrlichia chaffeensis development.ehrlichia chaffeensis, an obligatory intracellular gram-negative bacterium, must take up various nutrients and metabolic compounds because it lacks many genes involved in metabolism. nutrient uptake by a gram-negative bacterium occurs primarily through pores or channels in the bacterial outer membrane. here we demonstrate that isolated e. chaffeensis outer membranes have porin activities, as determined by a proteoliposome swelling assay. the activity was partially blocked by an antibody that rec ...200818359808
molecular characterization of bartonella vinsonii subsp. berkhoffii genotype iii.the molecular characterization of a bartonella vinsonii subsp. berkhoffii genotype iii strain (ncsu strain 06-co1) isolated from the blood of a military working dog diagnosed with endocarditis is reported in this study. several genes were amplified and sequenced for comparative sequence similarity with other strains.200818367567
more about the role of 2,6-dichlorophenol in tick courtship: identification and olfactometer bioassay in amblyomma cajennense and rhipicephalus sanguineus.this study aimed to identify 2,6-dichlorophenol (2,6-dcp) in amblyomma cajennense and to evaluate its role in a. cajennense and rhipicephalus sanguineus courtship. hexanic extract from attractive females was purified by solid phase extraction and the phenol was identified by the single ion monitoring method using gc/ms. in an olfactometer, the responses of a. cajennense and r. sanguineus males to females, control rubber septa or rubber septa impregnated with 2,6-dcp at 50, 500, and 5000 ng, resp ...200818368237
ehrlichia chaffeensis in child, venezuela. 200818325283
rickettsia slovaca in dermacentor marginatus and tick-borne lymphadenopathy, tuscany, italy.of 263 patients in tuscany, italy, from whom ticks were removed during july 2005-may 2007, five showed signs of tick-borne encephalopathy. of the ticks, 17 were dermacentor marginatus; 6 (35.3%) of these were identified by sequence analysis as containing rickettsia slovaca. tick-borne lympadenopathy occurs in this area.200818439371
degeneration of salivary glands of males of the tick rhipicephalus sanguineus (latreille, 1806) (acari, ixodidae).the present study examined the salivary glands of rhipicephalus sanguineus males at days 0, 3, and 7 post-detachment from the host. degeneration of this organ occurred in the three stages and it advanced as time away from the host progressed. thus, characteristics of degeneration were more prominent in males at day 7 post-detachment than in males at day 0 post-detachment. in males at day 0 post-detachment, type i acini were intact; while in other stages these acini exhibited signs of degeneratio ...200818450383
ticks biting humans in the urban area of istanbul.a passive surveillance for tick bites in humans was undertaken in the city of istanbul (turkey) in the summer and autumn of 2006. from 1,054 reported tick bites, most were females of ixodes ricinus (27%) and nymphs of hyalomma aegyptium (50%). a few adults of hyalomma m. marginatum, rhipicephalus sanguineus and dermacentor marginatus were also recorded. we investigated potential risk factors for i. ricinus and h. aegyptium with spatial statistics. climate features at 1-km resolution (monthly min ...200818074152
a case of spotted fever group rickettsiosis imported into the united kingdom and treated with ciprofloxacin: a case report.spotted fever group rickettsioses are an interesting group of infections, which are increasing in incidence worldwide.200818387179
splenic rupture and malignant mediterranean spotted fever. 200818507929
efficacy of a single application of a 12.5% pyriprole topical solution against laboratory infestations with ticks (ixodes ricinus, dermacentor reticulatus, and rhipicephalus sanguineus) on dogs.in three separate studies, the efficacy of a single treatment with a 12.5% pyriprole spot-on solution was investigated against induced infestation with ixodes ricinus, dermacentor reticulatus and rhipicephalus sanguineus on dogs (both sexes; beagles in studies 1 and 2, mixed-breed in study 3). for each tick species, one group of 8 dogs left untreated (studies 1 and 2) or treated with a placebo solution (study 3) was compared with another group treated once with the spot-on solution at a dose rat ...200818455315
spotted fever group rickettsia in brown dog ticks rhipicephalus sanguineus in southwestern spain.a total of 2,229 adults ticks (1,428 males and 801 females) belonging to the brown dog tick, rhipicephalus sanguineus latreille, 1806, collected from dogs in seville province (andalusia), distributed in 500 lots ranging from one to eight specimens per lot, were examined for the presence of rickettsiae by molecular techniques. specific rickettsiae dna were detected in 90 lots (18%) of ticks tested. sequence analysis of amplicons revealed that r. sanguineus ticks were infected exclusively with ric ...200818340465
detection and molecular characterization of babesia canis vogeli from naturally infected dogs and rhipicephalus sanguineus ticks in tunisia.canine babesiosis, caused by intra-erythrocytic babesia, is a tick-borne disease of worldwide importance. no information on canine babesiosis has been documented in tunisia. detection and analysis of babesia species from naturally infected dogs and ticks recovered from dogs were attempted by reverse line blot hybridization and nucleotide sequence analysis based on 18s rrna gene. out of 180 blood samples collected from domestic dogs in 4 villages situated in different bioclimatic zones, 12 were p ...200818242865
the brown dog tick, rhipicephalus sanguineus (latreille, 1806) (acari: ixodidae): from taxonomy to control.rhipicephalus sanguineus, commonly known as the brown dog tick, is a three-host tick that feeds primarily on dogs and occasionally on other hosts, including humans. r. sanguineus ticks are widely distributed around the world and they are known vectors of pathogens, such as babesia canis, ehrlichia canis, and rickettsia conorii. the increasing number of cases of human parasitism by r. sanguineus ticks reported in the literature indicates that the interaction between humans and r. sanguineus ticks ...200818280045
chemical composition and larvicidal properties of the essential oils from drimys brasiliensis miers (winteraceae) on the cattle tick rhipicephalus (boophilus) microplus and the brown dog tick rhipicephalus sanguineus.the essential oil obtained from leaves and stem barks of the southern brazilian native drimys brasiliensis miers, a tree with medicinal properties, was analyzed by gas chromatography (gc) and gc/mass spectrometry (ms). the oil was characterized by sesquiterpenoids (66%), cyclocolorenone being the most abundant (30.4%), followed by bicyclogermacrene (11.8%) and alpha-gurjunene (6.0%). laboratory tests were carried out to determine the toxicity of the essential oil on larvae of the cattle tick rhi ...200818046578
the effect of water and shampooing on the efficacy of a pyriprole 12.5% topical solution against brown dog tick (rhipicephalus sanguineus) and cat flea (ctenocephalides felis) infestations on dogs.the efficacy of a single treatment with a 12.5% pyriprole spot-on formulation against induced infestations with r. sanguineus ticks and cat fleas (c. felis) as well as its persistence after repeated washing and shampooing was investigated in four separate studies. in a first study on r. sanguineus involving 32 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation ranged from 100% to 99.3%. no engorged ticks, alive or dead, ...200818061355
salp15 binding to dc-sign inhibits cytokine expression by impairing both nucleosome remodeling and mrna stabilization.ixodes ticks are major vectors for human pathogens, such as borrelia burgdorferi, the causative agent of lyme disease. tick saliva contains immunosuppressive molecules that facilitate tick feeding and b. burgdorferi infection. we here demonstrate, to our knowledge for the first time, that the ixodes scapularis salivary protein salp15 inhibits adaptive immune responses by suppressing human dendritic cell (dc) functions. salp15 inhibits both toll-like receptor- and b. burgdorferi-induced productio ...200818282094
cytoplasmic rna and nuclear changes detected cytochemically during the degeneration of salivary glands of the tick rhipicephalus sanguineus (latreille, 1806) (acari, ixodidae).the present study reports cytochemistry data about salivary glands of females (unfed, engorged, and at day three post-engorgement) and males (unfed, at day seven post-attachment, and at days three and seven post-detachment from the host) of the tick rhipicephalus sanguineus. the results revealed nuclear changes in engorged females and at day three post-engorgement, and in males in all stages (except unfed). these changes were more prominent in females. cytoplasmic changes were also observed in c ...200818061463
genetic and antigenic diversities of major immunoreactive proteins in globally distributed ehrlichia canis strains.the extent of knowledge regarding the diversity of globally distributed ehrlichia canis strains has been limited to information gained from a few evolutionarily conserved genes. in this study, e. canis strains from the united states (strain jake [us]), brazil (strain são paulo [br]), and israel (strain 611 [is] and ranana [is-r]) were used to examine the antigenic and genetic diversities of four well-characterized major immunoreactive protein genes/proteins. gp36 and gp200 were the most divergen ...200818480237
host surveys, ixodid tick biology and transmission scenarios as related to the tick-borne pathogen, ehrlichia canis.the ehrlichioses have been subject to increasing interest from veterinary and public health perspectives, but experimental studies of these diseases and their etiologic agents can be challenging. ehrlichia canis, the primary etiologic agent of canine monocytic ehrlichiosis, is relatively well characterized and offers unique advantages and opportunities to study interactions between a monocytotropic pathogen and both its vertebrate and invertebrate hosts. historically, advances in tick-borne dise ...200818963493
rickettsia conorii transcriptional response within inoculation eschar.rickettsia conorii, the causative agent of the mediterranean spotted fever, is transmitted to humans by the bite of infected ticks rhipicephalus sanguineus. the skin thus constitutes an important barrier for the entry and propagation of r. conorii. given this, analysis of the survival strategies used by the bacterium within infected skin is critical for our understanding of rickettsiosis.200818997861
evaluation of cytotoxic effects of fipronil on ovaries of semi-engorged rhipicephalus sanguineus (latreille, 1806) (acari: ixodidae) tick female.the ovary of the rhipicephalus sanguineus dog tick female is structurally formed by oocytes in five different stages of development (from i to v) and attached to the gonad by the pedicel. the present study evaluated possible toxic effects of the acaricide fipronil (frontline) on ovaries of semi-engorged ticks. sixty partially fed females of r. sanguineus tick were distributed into four groups of 15 specimens each: i--non-treated; ii, iii and iv--treated with 1, 5 and 10 ppm of fipronil, respecti ...200818501493
toxicity of extract of magonia pubescens (sapindales: sapindaceae) st. hil. to control the brown dog tick, rhipicephalus sanguineus (latreille) (acari: ixodidae).the action of crude ethanol extract of the stem bark of the soapberry magonia pubescens st. hil. was studied upon larvae of the brown dog tick rhipicephalus sanguineus (latreille). tick larvae were obtained by maintaining gravid females in an incubator, after collecting them from naturally infested kennels. the tick larvae were placed in envelopes of filter paper impregnated with different concentrations of the extract dissolved in dimethylsulfoxide (dmso) and distilled water. four tests were re ...200818506302
markers of cell death in salivary glands of males of the tick rhipicephalus sanguineus (latreille, 1806) (acari, ixodidae).the salivary glands of rhipicephalus sanguineus males at stages: unfed (control), at day seven post-attachment, and at days three and seven post-detachment from the host were examined using methods of enzymatic analysis and cell viability. at these stages of feeding, different staining patterns were observed in the cells of type iv, iii, ii and i acini, which were affected by degeneration in this sequence. acid phosphatase reaction was inversely proportional to that of atpase, while atpase react ...200818514570
exploring the mialome of ticks: an annotated catalogue of midgut transcripts from the hard tick, dermacentor variabilis (acari: ixodidae).ticks are obligate blood feeders. the midgut is the first major region of the body where blood and microbes ingested with the blood meal come in contact with the tick's internal tissues. little is known about protein expression in the digestive tract of ticks. in this study, for analysis of global gene expression during tick attachment and feeding, we generated and sequenced 1,679 random transcripts (ests) from cdna libraries from the midguts of female ticks at varying stages of feeding.200819021911
defining the immune response to ehrlichia species using murine models.pathogenic bacteria belonging to the family anaplasmataceae include species of the genera ehrlichia and anaplasma. ehrlichia chaffeensis, first known as the causative agent of human monocytic ehrlichiosis, also infects several vertebrate hosts including white-tailed deer, dogs, coyotes and goats. e. chaffeensis is transmitted from the bite of an infected hard tick, such as amblyomma americanum. e. chaffeensis and other tick-transmitted pathogens have adapted to both the tick and vertebrate host ...200819028013
[control of rhipicephalus sanguineus (latrielle, 1806) (acari: ixodidae) in the kennel of the ufmg veterinary school, belo horizonte, minas gerais, brazil].the present work was aimed at proposing a control measure for rhipicephalus sanguineus in a naturally infected kennel of 72 m(2) of the ufmg veterinary school with 25 dogs of different breeds. a sensitivity test to acaricide products was applied in a sample of r. sanguineus. out of the acaricide products tested: 12.5% amitraz (product 1); 2% alfamethrin and 60% dichlorvos association (product 2); 5% deltamethrin (product 3) and the association between 77.6% trichlorfon, 1.0% coumaphos and 1.0% c ...200818554440
ticks infesting domestic animals in northern greece.the tick species infesting grazing animals in the countryside of 11 prefectures in northern greece were investigated during april-july and september-december of consecutive years 2003-2006. a total of 3,249 (1,952 males, 1,297 females) adult ticks were collected from goats, sheep, cattle and dogs. ticks were identified as ixodes ricinus (44.57%), ixodes gibbosus (4.09%), rhipicephalus bursa (19.14%), rhipicephalus sanguineus, rhipicephalus turanicus (5.79%), hyalomma marginatum marginatum (12.40 ...200818563592
fatal case of israeli spotted fever after mediterranean cruise. 200819046528
[mediterranean spotted fever: new trends and new questions]. 200818598863
parasites of importance for human health in nigerian dogs: high prevalence and limited knowledge of pet owners.dogs are the most common pet animals worldwide. they may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. in nigeria, epidemiological knowledge on these parasites is limited.200819068110
movement of rhipicephalus sanguineus adults between co-housed dogs during active feeding.adult male ticks have been shown capable of experimental acquisition and transmission of tick-borne pathogens without requiring a molt. to determine the ecological relevance of this intrastadial transmission route, we evaluated the extent to which actively feeding male rhipicephalus sanguineus move naturally between co-housed infested dogs. dogs (n=4) were infested with single color-coded ticks, individually housed in tick-confinement cages for 48 h while infestations established, and then each ...200717904292
lateral gene transfer between obligate intracellular bacteria: evidence from the rickettsia massiliae genome.rickettsia massiliae is a tick-borne obligate intracellular alpha-proteobacteria causing spotted fever in humans. here, we present the sequence of its genome, comprising a 1.3-mb circular chromosome and a 15.3-kb plasmid. the chromosome exhibits long-range colinearity with the other spotted fever group rickettsia genomes, except for a large fragment specific to r. massiliae that contains 14 tra genes presumably involved in pilus formation and conjugal dna transfer. we demonstrate that the tra re ...200717916642
dose determination of a novel formulation of metaflumizone plus amitraz for control of cat fleas (ctenocephalides felis felis) and brown dog ticks (rhipicephalus sanguineus) on dogs.a novel spot-on formulation containing metaflumizone and amitraz (promeris/promeris duo for dogs, fort dodge animal health, overland park, ks) was evaluated in a laboratory study to determine the appropriate dose for efficacy against fleas and ticks on dogs for 1 month. thirty-six beagles were randomly allocated to six equal groups and individually housed. one group remained nontreated. another was treated with a placebo formulation (solvents with no active ingredients). three groups of dogs wer ...200717931781
rickettsia infection in five areas of the state of são paulo, brazil.this study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of são paulo. eight flea species (adoratopsylla antiquorum antiquorum, ctenocephalides felis felis, polygenis atopus, polygenis rimatus, polygenis roberti roberti, polygenis tripus, rhopalopsyllus lugubris, and rhopalopsyllus lutzi lutzi), and five tick species (amblyomma aureolatum, amblyomma cajennense, amblyomma dubitatum, ixodes loricatus, and rhipicephalus sanguineus) were ...200718094887
tick fauna from two locations in the brazilian savannah.the cerrado is brazil's tropical savannah, which is arguably under greater threat than the amazon rainforest. the cerrado biome of tropical south america covers about 2 million km(2) and is considered a biodiversity hot spot which means that it is especially rich in endemic species and particularly threatened by human activities. the cerrado is increasingly exposed to agricultural activities which enhance the likelihood of mixing parasites from rural, urban and wildlife areas. information about ...200717828441
[influence of aggregation on the molting process of rhipicephalus sanguineus, (latreille, 1806) (acari: ixodidae) under laboratory conditions].the objective of this experiment was to evaluate the influence of different aggregations on the molting process of rhipicephalus sanguineus (latreille, 1806). tick-naïve domestic rabbits (oryctolagus cuniculus) were used as experimental hosts for the parasitic phase. a total of 10 rabbits were used on the experiment. all tick free-living phases were kept in incubator at 27+/-1 degrees c, 80+/-5% relative humidity and scotophase. the periods of pre-molt, molt, percentage of ecdisis and molt rhyth ...200718373896
anaphylactic shock caused by tick (rhipicephalus sanguineous). 200717694706
screening dogs in ontario for borrelia burgdorferi and ehrlichia canis should be selective rather than routine. 200717824154
rickettsia conorii israeli tick typhus strain isolated from rhipicephalus sanguineus ticks in portugal.this report describes the first establishment of five isolates of r. conorii israeli tick typhus (itt) strain from rhipicephalus sanguineus ticks in different regions of portugal. ticks were collected on two separate expeditions that took place in bragança, montesinho natural park, and portalegre city.200717767403
animal babesiosis: an emerging zoonosis also in italy?in italy, babesiosis is widespread in several central and southern regions, but few data are available on its presence in most italian areas. in 2004 a project was financed by the miur to investigate on the babesiosis epidemiology in vertebrate and invertebrate hosts, and on the transmission risk for humans in central and northern regions of the country. microscopy and/or molecular tools were applied to blood samples of wild animals, livestock and pets, and to 1,677 ticks collected on animals or ...200717691605
man-threatening viruses isolated from ticks in saudi arabia.to determine tick viruses transmissible to man in saudi arabia.200718060218
hepatozoon canis infection in slovakia: imported or autochthonous?tissue samples from nine red foxes (four samples of striated muscle tissue and five samples of heart tissue) that originated from the michalovce district (slovakia), an area with endemic occurrence of canine babesiosis were examined by pcr method using primers amplifying a fragment of the 18s rrna spanning the v4 region of babesia and theileria. an unexpected determination of 450 bp dna fragment of hepatozoon canis was found in four samples. partial sequences of the 18s rrna gene from the h. can ...200717627439
molecular cloning and characterization of a highly selective chemokine-binding protein from the tick rhipicephalus sanguineus.ticks are blood-feeding parasites that secrete a number of immuno-modulatory factors to evade the host immune response. saliva isolated from different species of ticks has recently been shown to contain chemokine neutralizing activity. to characterize this activity, we constructed a cdna library from the salivary glands of the common brown dog tick, rhipicephalus sanguineus. pools of cdna clones from the library were transfected into hek293 cells, and the conditioned media from the transfected c ...200717640866
life cycle of hepatozoon canis (apicomplexa: adeleorina: hepatozoidae) in the tick rhipicephalus sanguineus and domestic dog (canis familiaris).the life cycle of the apicomplexan protozoon hepatozoon canis in its natural hosts rhipicephalus sanguineus (tick) and canis familiaris (domestic dog) was studied in an experimental infection. tick nymphs were fed on a naturally infected dog, or they were infected by percutaneous injection of blood. dogs were inoculated by ingestion of adult ticks containing mature oocysts. gamonts were in syzygy 24 hr after percutaneous injection of ticks. early oocysts were detected 96 hr after nymph repletion ...200717539411
detection of rickettsia rickettsii and bartonella henselae in rhipicephalus sanguineus ticks from california.sixty-two questing adult rhipicephalus sanguineus (latreille) ticks were collected by direct removal from blades of turfgrass and adjacent concrete walkways at a suburban home in riverside county, ca, and tested for the presence of rickettsia, bartonella, and ehrlichia dna. polymerase chain reaction (pcr) was used to amplify fragments of the 17-kda antigen gene and the rompa gene of the spotted fever group rickettsiae. one male tick contained r. rickettsii dna; its genotype differed from r. rick ...200717294935
molecular typing of isolates of rickettsia rickettsii by use of dna sequencing of variable intergenic regions.rickettsia rickettsii, the causative agent of rocky mountain spotted fever, is found throughout the americas, where it is associated with different animal reservoirs and tick vectors. no molecular typing system currently exists to allow for the robust differentiation of isolates of r. rickettsii. analysis of eight completed genome sequences of rickettsial species revealed a high degree of sequence conservation within the coding regions of chromosomes in the genus. intergenic regions between codi ...200717553977
rocky mountain spotted fever, colombia.we investigated 2 fatal cases of rocky mountain spotted fever that occurred in 2003 and 2004 near the same locality in colombia where the disease was first reported in the 1930s. a retrospective serosurvey of febrile patients showed that > 21% of the serum samples had antibodies aaainst spotted fever group rickettsiae.200718214179
identification of rickettsial isolates at the species level using multi-spacer typing.in order to estimate whether multi-spacer typing (mst), based on the sequencing of variable intergenic spacers, could serve for the identification of rickettsia at the species level, we applied it to 108 rickettsial isolates or arthropod amplicons that include representatives of 23 valid rickettsia species.200717662158
anaplasma platys in dogs, chile.we conducted a 16s rrna nested pcr for the genus ehrlichia and ehrlichia spp. with blood samples from 30 ill dogs in chile. phylogenetic analysis was performed by using groesl gene amplification. we identified anaplasma platys as 1 of the etiologic agents of canine ehrlichiosis.200718252119
rickettsia monacensis and human disease, spain.we identified rickettsia monacensis as a cause of acute tickborne rickettsiosis in 2 humans. its pathogenic role was assessed by culture and detection of the organism in patients' blood samples. this finding increases the number of recognized human rickettsial pathogens and expands the known geographic distribution of mediterranean spotted fever-like cases.200718252123
q fever (coxiella burnetii) among man and farm animals in north sinai, egypt.antibodies against coxiella burnetii were estimated among sheep, goats and camels (190), their owners (150 patients with pyrexia of unknown origin) and 30 normal individuals in north sinai over the 2006 by indirect immounofluorescence assay. nested polymerase chain reaction was used to detect com-1 gene (genetic target of c. burnetii) encoding a 27-kda outer membrane protein in the samples. c. burnetii ifa antibodies (igm & igg) in patients were 8 (5.3%) and a healthy control (3.3%). the overall ...200717580573
differential interaction of dendritic cells with rickettsia conorii: impact on host susceptibility to murine spotted fever rickettsiosis.spotted fever group rickettsioses are emerging and reemerging infectious diseases, some of which are life-threatening. in order to understand how dendritic cells (dcs) contribute to the host resistance or susceptibility to rickettsial diseases, we first characterized the in vitro interaction of rickettsiae with bone marrow-derived dcs (bmdcs) from resistant c57bl/6 (b6) and susceptible c3h/hen (c3h) mice. in contrast to the exclusively cytosolic localization within endothelial cells, rickettsiae ...200717403875
sero-prevalence and risk indicators for canine ehrlichiosis in three rural areas of brazil.ehrlichia canis has a worldwide geographic distribution, occurring particularly in tropical and subtropical areas. in brazil, the main vector in urban areas is believed to be the brown dog tick rhipicephalus sanguineus, but little is known about the occurrence, transmission and other epidemiological aspects of canine ehrlichiosis in rural areas, where amblyomma ticks are found more frequently than r. sanguineus. a sero-prevalence study of canine ehrlichiosis was carried out in three distinct rur ...200717204439
detection of "rickettsia sp. strain uilenbergi" and "rickettsia sp. strain davousti" in amblyomma tholloni ticks from elephants in africa.to date, 6 tick-borne rickettsiae pathogenic for humans are known to occur in africa and 4 of them were first identified in ticks before being recognized as human pathogens.200717683629
tick acquisition of ehrlichia canis from dogs treated with doxycycline hyclate.doxycycline generally alleviates clinical monocytic ehrlichiosis, but its efficacy in the control of monocytotropic ehrlichial pathogens requires further investigation. in this study, ehrlichia canis was detected in dogs treated with doxycycline for 14 days and in ticks fed on these dogs, suggesting that treated dogs can remain reservoirs for e. canis.200717606682
coinfection with multiple tick-borne and intestinal parasites in a 6-week-old dog.coinfection with ehrlichia canis, babesia canis, hepatozoon canis, isospora spp., giardia spp., and dipylidium caninum were detected in a 6-week-old dog. the effect of multi-pathogen infection was a fatal combination of gastrointestinal and hematologic abnormalities, including diarrhea, vomiting, anorexia, distended painful abdomen, intussusception, severe thrombocytopenia, anemia, and hypoproteinemia.200717616060
localization and visualization of a coxiella-type symbiont within the lone star tick, amblyomma americanum.a coxiella-type microbe occurs at 100% frequency in all amblyomma americanum ticks thus far tested. using laboratory-reared ticks free of other microbes, we identified the amblyomma-associated coxiella microbe in several types of tissue and at various stages of the life cycle of a. americanum by 16s rrna gene sequencing and diagnostic pcr. we visualized amblyomma-associated coxiella through the use of a diagnostic fluorescence in situ hybridization (fish) assay supplemented with pcr-based detect ...200717720830
life cycles of seven ixodid tick species (acari: ixodidae) under standardized laboratory conditions.studies of transmission, maintenance, infectivity, virulence, and pathogenicity of tick-borne agents require the use of large numbers of live laboratory-raised ticks. colonies of ixodes scapularis say, ixodes pacificus cooley & kohls, amblyomma americanum (l.), dermacentor occidentalis marx, dermacentor variabilis (say), hemaphysalis leporispalustris (packard), and rhipicephalus sanguineus (latrielle) have been maintained in our laboratory at the centers for disease control and prevention for fi ...200717915502
hyalomma aegyptium as dominant tick in tortoises of the genus testudo in balkan countries, with notes on its host preferences.collection of 1327 ticks sampled throughout greece, bulgaria, romania and croatia, from 211 tortoises belonging to three species, testudo marginata schoepff, t. graeca linnaeus, and t. hermanni gmelin, revealed the presence of four species of ixodid ticks, namely hyalomma aegyptium (linnaeus), haemaphysalis sulcata canestrini and fanzago, h. inermis birula and rhipicephalus sanguineus (latreille). study confirmed the strong dominance of all life stages of h. aegyptium among ticks parasitizing we ...200717237970
confirmation of the efficacy of a novel formulation of metaflumizone plus amitraz for the treatment and control of fleas and ticks on dogs.a novel spot-on formulation containing metaflumizone plus amitraz (promeris/promeris duo for dogs, fort dodge animal health, overland park, ks) was evaluated in four laboratory studies to confirm efficacy against fleas and ticks on dogs for 1 month. three different strains of cat flea (ctenocephalides felis felis) and four tick species were used. rhipicephalus sanguineus and dermacentor variabilis were evaluated concurrently in two studies and ixodes scapularis and amblyomma americanum in one st ...200717923330
real-time pcr investigation of potential vectors, reservoirs, and shedding patterns of feline hemotropic mycoplasmas.three hemotropic mycoplasmas have been identified in pet cats: mycoplasma haemofelis, "candidatus mycoplasma haemominutum," and "candidatus mycoplasma turicensis." the way in which these agents are transmitted is largely unknown. thus, this study aimed to investigate fleas, ticks, and rodents as well as saliva and feces from infected cats for the presence of hemotropic mycoplasmas, to gain insight into potential transmission routes for these agents. dna was extracted from arthropods and from rod ...200717468284
prevalence of ehrlichia canis (rickettsiales: anaplasmataceae) in dogs and rhipicephalus sanguineus (acari: ixodidae) ticks from brazil.the current study evaluated the prevalence of ehrlichia canis donatien and lestoquard in domestic dogs, canis familiaris l., and rhipicephalus sanguineus (latreille) (acari: ixodidae) ticks from different areas of brazil. in monte negro county (state of rondônia, brazilian western amazon), the indirect immunofluorescence assay detected e. canis-reactive antibodies (titer > or = 40) in 58/153 (37.9%) and 40/161 (24.8%) dogs from the urban and rural areas, respectively. these values were significa ...200717294930
isolation of rickettsia rhipicephali and rickettsia bellii from haemaphysalis juxtakochi ticks in the state of são paulo, brazil.in the present study, attempts to isolate rickettsia in cell culture were performed individually in seven specimens of haemaphysalis juxtakochi ticks collected in the state of são paulo (southeastern brazil). rickettsia was successfully isolated by the shell vial technique and established in vero cell culture from six ticks (six isolates). dna extracted from infected cells of these isolates was tested by pcr and dna sequencing, using genus-specific rickettsia primers targeting the genes glta, ht ...200717142361
experimental infection of dairy calves with ehrlichia chaffeensis.human monocytic ehrlichiosis (hme) is a zoonotic emerging tick-borne disease with clinical signs that range from mild symptoms to multiple organ failure and death. ehrlichia chaffeensis, the aetiologic agent of hme, is reported to infect a divergent range of mammals. although cattle are common hosts of the primary vector of this pathogen, the susceptibility of this host to e. chaffeensis has not been reported to date. this study was undertaken to determine if cattle could provide a useful infect ...200718033836
outbreak of canine monocytic ehrlichiosis in saudi arabia.canine monocytic ehrlichiosis (cme) is a widespread tickborne infection of canids caused by ehrlichia canis, a gram-negative obligatory intracellular bacteria belonging to the family anaplasmataceae. cme is reported to have worldwide distribution, but its presence in a region requires the presence of the vector, the brown dog tick rhipicephalus sanguineus.200718041697
ticks and associated pathogens collected from domestic animals in the netherlands.following an outbreak of autochthonous canine babesiosis in the netherlands, a request made to veterinarians and the public to collect ticks from companion animals resulted in 4298 ticks submitted between july 2005 and october 2006 to our center. ticks were identified as ixodes ricinus adults (2907/4298, 67.6%), ixodes sp. nymphs (529/4298, 12.3%) and ixodes sp. larvae (385/4298, 9.0%), i. hexagonus adults (328/4298, 7.6%), dermacentor reticulatus (72/4298, 1.7%), and several other exotic tick s ...200717979540
[a descriptive epidemiological study on canine babesiosis in the lake geneva region].a descriptive study was carried out in the district of the lake geneva between march 1, 2005 and august 31,2006 to assess the incidence and prevalence of canine babesiosis, to genotype the babesia species occurring, to assess the most frequently clinical signs found and to address the potential of autochthonous transmission. this included a data assessment on the different tick-populations occurring in the area and on the prevalence of babesia-dna in these ticks. a total of 56 veterinary practic ...200717983018
prevalence of ixodid ticks on cattle in mazandaran province, iran.a survey was carried out to investigate the prevalence of hard tick species (acari: ixodidae) on cattle in mazandaran province, iran. a total of 953 ticks were collected from 86 infested cattle during activating seasons of ticks during 2004-2005. nine species were identified: boophilus annulatus (51.3%), rhipicephalus bursa (16.8%), haemaphysalis punctata (6.3%), ixodes ricinus (6.8%), hyalomma marginatum (12.5%), hyalomma anatolicum excavatum (5.2%), hyalomma asiaticum (0.6%), hyalomma detritum ...200718165714
highly prevalent coxiella sp. bacterium in the tick vector amblyomma americanum.laboratory-reared and field-collected amblyomma americanum ticks were hosts of a coxiella sp. and a rickettsia sp. while the coxiella sp. was detected in 50 of 50 field-collected ticks, the rickettsia sp. was absent from 32% of ticks. the coxiella sp. showed evidence of a reduced genome and may be an obligate endosymbiont.200717085709
differential clearance and immune responses to tick cell-derived versus macrophage culture-derived ehrlichia chaffeensis in mice.human monocytic ehrlichiosis is caused by a tick-transmitted rickettsia, ehrlichia chaffeensis. we recently reported that e. chaffeensis grown in tick cells expresses different proteins than bacteria grown in macrophages. therefore, we tested the hypothesis that immune responses against e. chaffeensis would be different if the mice are challenged with bacteria grown in macrophages or tick cells. we assessed the e. chaffeensis clearance from the peritoneum, spleen, and liver by c57bl/6j mice usin ...200717060466
infection of ixodes scapularis ticks with rickettsia monacensis expressing green fluorescent protein: a model system.ticks (acari: ixodidae) are ubiquitous hosts of rickettsiae (rickettsiaceae: rickettsia), obligate intracellular bacteria that occur as a continuum from nonpathogenic arthropod endosymbionts to virulent pathogens of both arthropod vectors and vertebrates. visualization of rickettsiae in hosts has traditionally been limited to techniques utilizing fixed tissues. we report epifluorescence microscopy observations of unfixed tick tissues infected with a spotted fever group endosymbiont, rickettsia m ...200717125789
species diversity and seasonality of free-living ticks (acari: ixodidae) in the natural habitat of wild marsh deer (blastocerus dichotomus) in southeastern brazil.this study evaluated the presence and seasonal activity of free-living ticks in remaining marsh areas by the paraná river, in brazil. eight field trips (once per season) for collection of ticks were performed during 2 years. using co2 traps, dragging, and visual inspection of vegetation, five free-living tick species were collected, in the following order of abundance: amblyomma cajennense, amblyomma dubitatum, amblyomma triste, amblyomma coelebs, and amblyomma nodosum. the seasonal pattern of a ...200716962241
uninfected mosquito bites confer protection against infection with malaria parasites.despite decades of research and multiple initiatives, malaria continues to be one of the world's most debilitating infectious diseases. new insights for malaria control and vaccine development will be essential to thwart the staggering worldwide impact of this disease (a. bjorkman and a. bhattarai, acta trop. 94:163-169, 2005); ultimately successful vaccine strategies will undoubtedly be multifactorial, incorporating multiple antigens and targeting diverse aspects of the malaria parasites' biolo ...200717339356
francisella tularensis, portugal. 200717561575
gene silencing of the tick protective antigens, bm86, bm91 and subolesin, in the one-host tick boophilus microplus by rna interference.the use of rna interference (rnai) to assess gene function has been demonstrated in several three-host tick species but adaptation of rnai to the one-host tick, boophilus microplus, has not been reported. we evaluated the application of rnai in b. microplus and the effect of gene silencing on three tick-protective antigens: bm86, bm91 and subolesin. gene-specific double-stranded (dsrna) was injected into two tick stages, freshly molted unfed and engorged females, and specific gene silencing was ...200717196597
ehrlichia species in rhipicephalus sanguineus ticks in cameroon.ehrlichia and anaplasma species are tick-transmitted obligately intracellular bacteria that commonly cause disease in dogs worldwide. in addition to causing disease in canines, ehrlichia chaffeensis, ehrlichia ewingii, and anaplasma phagocytophilum are responsible for emerging and life-threatening human zoonoses in the united states. we previously reported a high prevalence of e. canis infection in cameroonian dogs based on serologic and molecular evidence. this study was undertaken to determine ...200717627442
the complete mitochondrial genome of pseudocellus pearsei (chelicerata: ricinulei) and a comparison of mitochondrial gene rearrangements in arachnida.mitochondrial genomes are widely utilized for phylogenetic and population genetic analyses among animals. in addition to sequence data the mitochondrial gene order and rna secondary structure data are used in phylogenetic analyses. arachnid phylogeny is still highly debated and there is a lack of sufficient sequence data for many taxa. ricinulei (hooded tickspiders) are a morphologically distinct clade of arachnids with uncertain phylogenetic affinities.200717961221
the complete mitochondrial genome of the sea spider achelia bituberculata (pycnogonida, ammotheidae): arthropod ground pattern of gene arrangement.the phylogenetic position of pycnogonids is a long-standing and controversial issue in arthropod phylogeny. this controversy has recently been rekindled by differences in the conclusions based on neuroanatomical data concerning the chelifore and the patterns of hox expression. the mitochondrial genome of a sea spider, nymphon gracile (pycnogonida, nymphonidae), was recently reported in an attempt to address this issue. however, n. gracile appears to be a long-branch taxon on the phylogenetic tre ...200717908292
epidemiological features of mediterranean spotted fever, murine typhus, and q fever in split-dalmatia county (croatia), 1982-2002.we determined the epidemiological features of three zoonoses in hospitalized patients in southern croatia. patients were diagnosed by serological testing. clinical and epidemiological data were also collected. between 1982 and 2002, mediterranean spotted fever (msf) was diagnosed in 126 (incidence rate 1.27/100,000 per year), murine typhus (mt), in 57 (incidence rate 0.57/100,000 per year), and q fever in 170 (incidence rate 1.7/100,000 per year) patients. msf and q fever were characterized by a ...200717850690
the complete mitochondrial genome of the sea spider nymphon gracile (arthropoda: pycnogonida).mitochondrial genomes form units of genetic information replicating indepentently from nuclear genomes. sequence data (most often from protein-coding genes) and other features (gene order, rna secondary structure) of mitochondrial genomes are often used in phylogenetic studies of metazoan animals from population to phylum level. pycnogonids are primarily marine arthropods, often considered closely related to chelicerates (spiders, scorpions and allies). however, due to their aberrant morphology ...200617087824
the environmental-endocrine basis of gynandromorphism (intersex) in a crustacean.commensurate with the decline in many crustacean populations has been an accumulation in reports of sexually ambiguous individuals within these populations. the cause of gynandromorphism or intersex among crustaceans is unknown. we show that gynandromorphism in the branchiopod crustacean daphnia magna is initiated by the sex-determining hormone methyl farnesoate when levels of the hormone are intermediate between low levels that stimulate the production of broods containing all female offspring ...200617205107
a case of histologically diagnosed tick infestation on the scalp of a korean child.a scalp mass surgically excised from a 4-year-old korean boy was identified as a tick through histological observations. in sections of the mass, characteristic features of a tick, including its gross contour, cuticular structures, well developed musculature and salivary glands, and the capitulum, were discovered. in particular, the capitulum is anteriorly protruded, which strongly suggests that the specimen be a hard tick of family ixodidae. however, the present histological features were not e ...200616809965
[ixodes ricinus. health risks and approaches in prevention].ticks belong to the parasitical mites. there are more than 1000 different species worldwide which do need blood of warm-blooded organisms for their own development. as ticks are well known to be vectors of several pathogens which could cause insidious infectious diseases, they are important in human and veterinarian medicine as well. it is not possible to control ticks in nature. therefore the first step should be an effective prevention. in case of a bite the tick must be removed as soon as pos ...200616719260
infection of human endothelial cells with spotted fever group rickettsiae stimulates cyclooxygenase 2 expression and release of vasoactive prostaglandins.rickettsiae, a diverse group of obligately intracellular gram-negative bacteria, include etiologic agents of the spotted fever and typhus groups of diseases. rocky mountain spotted fever and boutonneuse fever, due to rickettsia rickettsii and r. conorii, respectively, are characterized by widespread infection of the vascular endothelium, microvascular injury, and vasculitis. cultured human endothelial cells (ec) are highly susceptible to infection and respond by altering the expression of adhesi ...200616926398
phylogenetic analysis of "candidatus mycoplasma turicensis" isolates from pet cats in the united kingdom, australia, and south africa, with analysis of risk factors for infection.two hemotropic mycoplasmas have been recognized in cats, mycoplasma haemofelis and "candidatus mycoplasma haemominutum." we recently described a third feline hemoplasma species, designated "candidatus mycoplasma turicensis," in a swiss cat with hemolytic anemia. this isolate induced anemia after experimental transmission to two specific-pathogen-free cats and analysis of the 16s rrna gene revealed its close relationship to rodent hemotropic mycoplasmas. the agent was recently shown to be prevale ...200617035497
spotted fever group rickettsiae in ticks feeding on humans in northwestern spain: is rickettsia conorii vanishing?during a 7-year study, we identified and analyzed by pcr 4,049 ticks removed from 3,685 asymptomatic patients in castilla y león (northwestern spain). a total of 320 ticks (belonging to 10 species) were pcr-positive for rickettsiae. comparison of amplicon sequences in databases enabled us to identify eight different spotted fever group (sfg) rickettsiae: rickettsia slovaca, rickettsia sp. irs3/irs4, r. massiliae/bar29, r. aeschlimannii, rickettsia sp. rpa4/dns14, r. helvetica, rickettsia sp. dms ...200617114733
rocky mountain spotted fever in arizona: documentation of heavy environmental infestations of rhipicephalus sanguineus at an endemic site.a recent epidemiologic investigation identified 16 cases and 2 deaths from rocky mountain spotted fever (rmsf) in two eastern arizona communities. prevalence studies were conducted by collecting free-living ticks (acari: ixodidae) from the home sites of rmsf patients and from other home sites within the community. dry ice traps and flagging confirmed heavy infestations at many of the home sites. only rhipicephalus sanguineus ticks were identified and all developmental stages were detected. it is ...200617114735
an outbreak of rocky mountain spotted fever associated with a novel tick vector, rhipicephalus sanguineus, in arizona, 2004: preliminary report.this study describes preliminary results of an investigation of rmsf in arizona associated with the brown dog tick, rhipicephalus sanguineus. high numbers of dogs and heavy infestations of ticks created a situation leading to human disease.200617114736
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