| 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 ... | 2007 | 17828441 |
| ticks collected on birds in the state of são paulo, brazil. | the present study reports a collection of amblyomma spp. ticks in birds from several areas of the state of são paulo, brazil. a total of 568 tick specimens (404 larvae, 164 nymphs) were collected from 261 bird specimens. from these ticks, 204 (36%) specimens (94 larvae, 110 nymphs) were reared to the adult stage, being identified as amblyomma longirostre (94 larvae, 90 nymphs), amblyomma calcaratum (13 nymphs), amblyomma nodosum (2 nymphs), and amblyomma cajennense (5 nymphs). additionally, 39 l ... | 2007 | 17882514 |
| a hard tick relapsing fever group spirochete in a brazilian rhipicephalus (boophilus) microplus. | tick-borne diseases usually comprise a complex epidemiological and ecological network connecting the vector, pathogen, and a group of host species. symptoms associated with lyme disease have been reported in brazil, but no borrelia sp. has been definitively related to these events. here we have identified a b. lonestari/b. theileri-related spirochete dna in the cattle tick rhipicephalus (boophilus) microplus from brazil. four hundred r. microplus and 80 amblyomma cajennense ticks were screened, ... | 2007 | 17979536 |
| plasmids of the prm/prf family occur in diverse rickettsia species. | the recent discoveries of the prf and prm plasmids of rickettsia felis and r. monacensis have contravened the long-held dogma that plasmids are not present in the bacterial genus rickettsia (rickettsiales; rickettsiaceae). we report the existence of plasmids in r. helvetica, r. peacockii, r. amblyommii, and r. massiliae isolates from ixodid ticks and in an r. hoogstraalii isolate from an argasid tick. r. peacockii and four isolates of r. amblyommii from widely separated geographic locations cont ... | 2008 | 18065613 |
| 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 ... | 2007 | 18094887 |
| 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. | 2007 | 18214179 |
| new morphological data on fat bodies of semi-engorged females of amblyomma cajennense (acari: ixodidae). | the present ultramorphological, histological and ultrastructural study on the fat body of semi-engorged females of amblyomma cajennense revealed that this tissue is diffuse and consists of strands of cells surrounding the tracheal trunks. morphometric analysis showed that the cellular and nuclear areas of round-shaped trophocytes are larger than those of cuboidal trophocytes, indicating that the arrangement of the former provides more contact area with the haemolymph. in this species, the fat bo ... | 2008 | 18215525 |
| rocky mountain spotted fever, panama. | we describe a fatal pediatric case of rocky mountain spotted fever in panama, the first, to our knowledge, since the 1950s. diagnosis was established by immunohistochemistry, pcr, and isolation of rickettsia rickettsii from postmortem tissues. molecular typing demonstrated strong relatedness of the isolate to strains of r. rickettsii from central and south america. | 2007 | 18217566 |
| expressed sequence tags (ests) from the salivary glands of the tick amblyomma cajennense (acari: ixodidae). | the neotropical tick amblyomma cajennense is a significant pest to domestic animals, the most frequently human-biting tick in south america and the main vector of brazilian spotted fever (caused by rickettsia rickettsii), a deadly human disease. the purpose of this study is to characterize the adult a. cajennense salivary gland transcriptome by expressed sequence tags (ests). we report the analysis of 1754 clones obtained from a cdna library, which reveal mainly transcripts related to proteins i ... | 2008 | 18243270 |
| rickettsial infection in capybaras (hydrochoerus hydrochaeris) from são paulo, brazil: serological evidence for infection by rickettsia bellii and rickettsia parkeri. | in brazil, capybaras (hydrochoerus hydrochaeris) are important hosts for amblyomma ticks, which in turn can transmit rickettsiae to humans and animals. therefore, capybaras are potential sentinels for rickettsial infection. | 2007 | 18320102 |
| 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 ... | 2008 | 18368237 |
| [effect of the strategic control of amblyomma cajennense (fabricius, 1787) (acari: ixodidae) on the population of anocentor nitens (neumann, 1897) (acari: ixodidae) in equines]. | the objective of this study was to evaluate the effect of the amblyomma cajennense strategic control program on the anocentor nitens population. the acaricide treatments were carried out every seven days and divided in two series, the first one beginning in april 2004 (eight treatments) and the second beginning in july of the same year (five treatments), using pyrethroid chemical base - cypermethrin in the concentration of 0,015%. monthly it was evaluated the infestation of a. nitens in the ear ... | 2007 | 18373898 |
| [strategic control of amblyomma cajennense (fabricius, 1787) (acari: ixodidae) on horses, minas gerais, brazil - part i]. | the aim of this study was to verify the efficiency of a strategic control program of amblyomma cajennense in horses under field conditions. acaricide treatments were applied at seven days intervals and divided in two series, the first one beginning in april 2004 (eight treatments), and the second one beginning in july 2004 (five treatments), aiming to control larvae and nymphs of the tick. a pyrethroid chemical base cypermethrin 0.015% was used for spraying the horses. there was a reduction of 4 ... | 2007 | 18373899 |
| ornithine decarboxylase antizyme finder (oaf): fast and reliable detection of antizymes with frameshifts in mrnas. | ornithine decarboxylase antizymes are proteins which negatively regulate cellular polyamine levels via their affects on polyamine synthesis and cellular uptake. in virtually all organisms from yeast to mammals, antizymes are encoded by two partially overlapping open reading frames (orfs). a +1 frameshift between frames is required for the synthesis of antizyme. ribosomes change translation phase at the end of the first orf in response to stimulatory signals embedded in mrna. since standard seque ... | 2008 | 18384676 |
| rocky mountain spotted fever in argentina. | we describe the first molecular confirmation of rickettsia rickettsii, the cause of rocky mountain spotted fever (rmsf), from a tick vector, amblyomma cajennense, and from a cluster of fatal spotted fever cases in argentina. questing a. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in jujuy province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. dna of r. rickettsii was amplified from a pool ... | 2008 | 18385370 |
| molecular identification of rickettsia felis in ticks and fleas from an endemic area for brazilian spotted fever. | rickettsioses are arthropod-borne diseases caused by parasites from the order rickettsiales. the most prevalent rickettsial disease in brazil is brazilian spotted fever (bsf). this work intends the molecular detection of those agents in ectoparasites from an endemic area of bsf in the state of espírito santo. a total of 502 ectoparasites, among them amblyomma cajennense, amblyomma dubitatum (a. cooperi), riphicephalus sanguineus, anocentor nitens and ctenocephalides felis, was collected from dom ... | 2008 | 18425272 |
| ticks produce highly selective chemokine binding proteins with antiinflammatory activity. | bloodsucking parasites such as ticks have evolved a wide variety of immunomodulatory proteins that are secreted in their saliva, allowing them to feed for long periods of time without being detected by the host immune system. one possible strategy used by ticks to evade the host immune response is to produce proteins that selectively bind and neutralize the chemokines that normally recruit cells of the innate immune system that protect the host from parasites. we have identified distinct cdnas e ... | 2008 | 18678732 |
| morphological changes in the salivary glands of amblyomma cajennense females (acari: ixodidae) in different feeding stages on rabbits at first infestation. | this study examined salivary glands of unfed, partially engorged, and engorged females of the tick amblyomma cajennense on rabbits at first infestation using histological and histochemical techniques. in type i acini, no significant changes were observed among the three feeding conditions. in type ii acini of unfed females, c1, c2, and c4 cells were described for the first time in this species. in a comparison among the three feeding conditions, an increase in this acinus was observed, due to th ... | 2008 | 18685958 |
| 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 ... | 2008 | 18691408 |
| canine babesiosis caused by babesia canis vogeli in rural areas of the state of minas gerais, brazil and factors associated with its seroprevalence. | this epidemiological survey on canine babesiosis was carried out in three distinct rural regions (lavras, belo horizonte and nanuque) of the state of minas gerais, brazil. ticks and blood samples were collected during a dry season (lavras, n=92; belo horizonte, n=50; nanuque, n=102) and the subsequent rainy season (lavras, n=71; belo horizonte, n=28; nanuque, n=66) from dogs living on farms. plasma samples were analyzed by the indirect fluorescent antibody test for detection of anti-babesia cani ... | 2009 | 18723199 |
| experimental infection of opossums didelphis aurita by rickettsia rickettsii and evaluation of the transmission of the infection to ticks amblyomma cajennense. | the present study evaluated the infection of opossums (didelphis aurita) by rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of r. rickettsii to amblyomma cajennense ticks. three groups of opossums were evaluated: on day 0, group 1 (g1) was inoculated intraperitoneally with r. rickettsii; group 2 (g2) was infested by r. rickettsii-infected ticks; and group 3 (g3) was the uninfected control group. opossum rectal temperature was measured daily. blood samples were ... | 2008 | 18945194 |
| rickettsial spotted fever in capoeirão village, itabira, minas gerais, brazil. | the present study investigated the infection by spotted fever rickettsia in an endemic area for brazilian spotted fever (bsf; caused by rickettsia rickettsii) in minas gerais state, brazil. human, canine and equine sera samples, and amblyomma cajennense adult ticks collected in a rural area of itabira city, minas gerais state were tested for rickettsial infection. through immunofluorescence assay (ifa) we demonstrated the presence of antibodies anti-r. rickettsii in 8.2%, 81.3% and 100% of the h ... | 2008 | 18949349 |
| 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 ... | 2008 | 18963493 |
| 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. | 2008 | 19016440 |
| fat body cells of amblyomma cajennense partially engorged females (acari: ixodidae) and their role on vitellogenesis process. | during the process of arthropoda reproduction, the synthesis and uptake of proteins, carbohydrates, and lipids by oocytes is termed vitellogenesis. these compounds that will make up the yolk may be in ticks endogenously synthesized by the oocytes and/or exogenously produced by the fat body and pedicel cells. this study examined the fat body of amblyomma cajennense ticks at the cytochemical ultrastructural level to demonstrate the presence of lipids, proteins and carbohydrates in trophocytes. the ... | 2009 | 19041306 |
| rickettsia sp. in ixodes granulatus ticks, japan. | | 2008 | 19046539 |
| 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 ... | 2008 | 19058642 |
| field collection and genetic classification of tick-borne rickettsiae and rickettsiae-like pathogens from south texas: coxiella burnetii isolated from field-collected amblyomma cajennense. | we are reporting the first known isolation of the q-fever agent coxiella burnetii from field-collected cayenne ticks amblyomma cajennense in north america. q-fever affects a number of domestic ungulates where it can lead to abortion in sheep and goats. there is far less known about the disease's effects on wild species, primarily because of the tendency of the disease to self resolve and to provide long-term immunity to subsequent infections. the first recovery of c. burnetii in north america wa ... | 2008 | 19120212 |
| cutaneous basophilia in the resistance of goats to amblyomma cajennense nymphs after repeated infestations. | the acquisition of resistance in goats against amblyomma cajennense after repeated infestations and the role of inflammatory cells in this mechanism were investigated. ten naive goats aged 6 months were distributed into two groups: test (n= 5), infested thrice at 30-day intervals; and control (n= 5), infested once. nymphs (n= 115 per animal per infestation) were released inside alimentary chambers glued to the animal's dorsum and the following biological parameters were evaluated: yielding rate, ... | 2008 | 19120216 |
| effect of amblyomma cajennense ticks on the immune response of balb/c mice and horses. | this work evaluated the effect of the amblyomma cajennense tick on the immune response of balb/c mice and on horse lymph node cell proliferation. we observed that mice do not develop resistance to nymphs of this tick species and that lymphocyte proliferation of this host is inhibited by tick saliva, nymphal extract, or infestations. horse lymph node cell proliferation is inhibited by tick saliva as well. mice lymphocytes under the effect of tick saliva, nymphal extract, or infestations display a ... | 2008 | 19120218 |
| experimental infection of capybaras hydrochoerus hydrochaeris by rickettsia rickettsii and evaluation of the transmission of the infection to ticks amblyomma cajennense. | the present study evaluated the infection of capybaras (hydrochoerus hydrochaeris) by rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of r. rickettsii to amblyomma cajennense ticks. two groups of two capybaras each were evaluated: on day 0, group 1 (g1) was infested by r. rickettsii-infected ticks, and group 2 (g2) was inoculated intraperitoneally with r. rickettsii. two additional groups were control groups, not exposed to r. rickettsii, being cg1 group the c ... | 2009 | 19147293 |
| rocky mountain spotted fever in dogs, brazil. | clinical illness caused by rickettsia rickettsii in dogs has been reported solely in the united states. we report 2 natural clinical cases of rocky mountain spotted fever in dogs in brazil. each case was confirmed by seroconversion and molecular analysis and resolved after doxycycline therapy. | 2009 | 19239764 |
| artificial feeding of amblyomma cajennense (acari: ixodidae) fasting females through capillary tube technique. | the present study aimed to adjust the artificial feeding technique through capillaries and to verify its influence over the biology of amblyomma cajennense females. five groups of 20 female ticks were formed. females were starved for 45 days and then fed with citrated bovine blood using capillary tubes in different periods of time. females were divided in five experimental groups with 20 individuals each and fed as follows: groups uninterruptedly fed for 12, 24, and 48 hours and groups fed 2 and ... | 2008 | 19245757 |
| notes on populational dynamics of amblyomma ticks (acari: ixodidae) in brazil. | previous populational dynamics data generated for amblyomma parvum aragão and amblyomma cajennense (fabricius) in argentina and southeastern brazil have indicated that these ticks complete 1 generation per yr, with larvae predominating in autumn, nymphs in winter, and adults mostly during spring and summer. the present study reports populational dynamics data for free-living amblyomma spp. ticks in northern brazil (amazon forest, latitude 10os), and for amblyomma spp. ticks collected on birds in ... | 2009 | 19256723 |
| [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 ... | 2008 | 19265575 |
| hepatozoon canis infecting dogs in the state of espírito santo, southeastern brazil. | from may 2007 to march 2008, blood samples were collected from 92 healthy dogs living in 21 households (17 farms in rural area, and 4 homes in urban area) in 6 counties of the state of espírito santo, southeastern brazil. in addition, ticks were collected from these dogs. a mean of 4.4+/-3.0 dogs (range: 1-12) were sampled per household; 78 and 14 dogs were from rural and urban areas, respectively. polymerase chain reaction (pcr) designed to amplify fragments of the 18s rdna gene of babesia spp ... | 2009 | 19482427 |
| ecology of rickettsia in south america. | until the year 2000, only three rickettsia species were known in south america: (i) rickettsia rickettsii, transmitted by the ticks amblyomma cajennense, and amblyomma aureolatum, reported in colombia, argentina, and brazil, where it is the etiological agent of rocky mountain spotted fever; (ii) rickettsia prowazekii, transmitted by body lice and causing epidemic typhus in highland areas, mainly in peru; (iii) rickettsia typhi, transmitted by fleas and causing endemic typhus in many countries. d ... | 2009 | 19538276 |
| [occurrence of ticks (acari: ixodidae) in the municipality of goiatins, tocantins]. | due to a suspected human case of brazilian lyme-like disease in the city of goiatins, tocantins state, an epidemiological survey was carried out in eight counties in this region during september 2007 and february 2008, where 1,890 ticks were collected from domestic animals and from the environment. a total of eight tick species were identified: rhipicephalus sanguineus, rhipicephalus (boophilus) microplus, dermacentor nitens, amblyomma cajennense, amblyomma oblongoguttatum, amblyomma ovale, ambl ... | 2009 | 19602318 |
| [survey of rickettsia spp in the ticks amblyomma cajennense and amblyomma dubitatum in the state of são paulo]. | the presence of rickettsial infection was surveyed in 3,545 amblyomma cajennense ticks and 2,666 amblyomma dubitatum ticks. using the hemolymph test, polymerase chain reaction and isolation of rickettsia in cell cultures, all of the amblyomma cajennense were negative, whereas 634 (23.8%) of the amblyomma dubitatum ticks were shown to be infected with rickettsia bellii. | 2009 | 19684990 |
| ticks (acari: ixodidae) within various phytophysiognomies of a cerrado reserve in uberlândia, minas gerais, brazil. | cerrado biome, the south american savannah, covers about 2 million km(2) and is very rich in endemic species but threatened by agriculture. in this report free-living tick species are presented, and their seasonal and relative distribution within the various phytophysiognomies in a small cerrado reserve in minas gerais state, brazil. overall 2,694 free-living ticks were found during a 2 years sampling period with co(2) traps and cloth dragging. of these, 73.5% were amblyomma cajennense and 0.6% ... | 2010 | 19693680 |
| tick-borne rickettsiosis in traveler returning from honduras. | | 2009 | 19751607 |
| ticks (acari: ixodidae) infesting birds in an atlantic rain forest region of brazil. | brazil has the third richest bird diversity of the world; however, there are few data concerning ticks (acari: ixodidae) parazitizing birds. the aim of the study was to report tick infestations on wild birds from an atlantic rain forest region of brazil. during 2 yr, ticks were collected from birds and from the environment in 12 forest sites. a total of 1,725 birds were captured representing 80 species from 24 families. in total, 223 (13%) birds were found infested by immature stages of amblyomm ... | 2009 | 19769058 |
| ticks on domestic animals in pernambuco, northeastern brazil. | the objective of this article was to discuss some aspects of ticks associated with domestic animals in the state of pernambuco, northeastern brazil, based on a literature review and present new data obtained from recent tick collections carried out in this northeastern brazilian state. from august 2007 to june 2008, 1,405 ticks were collected and five species were identified: amblyomma cajennense (fabricius, 1787), amblyomma ovale koch, 1844, dermacentor nitens neumann, 1897, rhipicephalus (boop ... | 2009 | 19772771 |
| a new factor xa inhibitor from amblyomma cajennense with a unique domain composition. | bioactive compounds of great interest are found in the saliva of hematophagous organisms. while exploring a cdna library derived from the salivary glands of the tick amblyomma cajennense, a transcript that codes for a protein with unique structure (containing an n-terminal kunitz-type domain and a c-terminus with no homology to any annotated sequences) was found. the recombinant mature form of this protein ( approximately 13.5kda) was produced in escherichia coli bl21 (de3), and it was able to i ... | 2010 | 19853573 |
| repellent activity of plant-derived compounds against amblyomma cajennense (acari: ixodidae) nymphs. | repellence responses of amblyomma cajennense nymphs to callicarpenal, intermedeol, hyptis suaveolens essential oil, extract of melia azedarach, cymbopogon nardus, spiranthera odoratissima, chenopodium ambrosioides, ageratum conyzoides, mentha pulegium, ruta graveolens, and memora nodosa were studied. among these the extract of c. nardus stood out because of the long-lasting repellence, maintaining, in the highest concentration, 35h of protection against 90% of the nymphs. the essential oil of h. ... | 2010 | 19897309 |
| histopathology and ultrastructure features of the midgut of adult females of the tick amblyomma cajennense fabricius, 1787 (acari: ixodidae) in various feeding stages and submitted to three infestations. | the digestive tube of the tick amblyomma cajennense is responsible for the digestion during feeding on the host. this study analyzed the midgut of unfed, partially engorged, and fully engorged fed females as well as three infestations in rabbits. in a. cajennense, the digestive tube is long and from the midgut, two pairs of diverticula ramify and lead to a blind end. in some midgut regions were observed for the first time in ticks, structures termed here "nodules." the midgut of unfed females po ... | 2009 | 19929171 |
| influence of photoperiod and temperature on the larval behavioral diapause of amblyomma cajennense (acari: ixodidae). | larval behavioral diapause was shown to be the major factor controlling the 1-yr generation pattern of amblyomma cajennense (f.) (acari: ixodidae) in brazil. during fieldwork, this behavior was shown to coincide with long daylength (>12 h) and high mean ground temperature (approximately =25 degrees c), which prevail during spring-summer in brazil. the current study evaluated biological parameters of engorged females, their eggs, and the resultant larvae inside plastic pots planted with the grass ... | 2009 | 19960674 |
| possible acquired resistance of dogs successively infested by amblyomma cajennense (fabricius, 1787) (acari: ixodidae) nymphs. | the present study aimed to evaluate the occurrence of immune resistance in dogs successively infested with amblyomma cajennense nymphs. five animals were submitted to four consecutive infestations with a. cajennense nymphs, at fourteen-day intervals. for each infestation, 50 nymphs were used per animal and data on the parasitic and non-parasitic periods were recorded. the average recovering rate of engorged nymphs in the successive infestations were 52.0, 29.2, 9.6 and 12.8%, respectively, with ... | 2009 | 20040189 |
| prevalence of equine piroplasmosis and its association with tick infestation in the state of são paulo, brazil. | serum samples were collected from 582 horses from 40 stud farms in the state of são paulo and tick (acari: ixodidae) infestations were evaluated on them. serum samples were subjected to the complement fixation test (cft) and a competitive inhibition elisa (celisa) for babesia caballi and theileria equi. logistic regression analyses were performed to construct multivariate models that could explain the dependent variable (horses positive for b. caballi or t. equi) as a function of the independent ... | 2009 | 20040201 |
| notes on population dynamics of amblyomma ticks (acari: ixodidae) in brazil. | previous population dynamics data, generated for amblyomma parvum aragão and amblyomma cajennense (fabricius) in argentina and southeastern brazil, have indicated that these ticks complete 1 generation per year, with larvae predominating in autumn, nymphs in winter, and mostly adults during spring and summer. the present study reports population dynamics data for free-living amblyomma spp. ticks in northern brazil (amazon forest, latitude 10 degrees s, 63 degrees w), and for amblyomma spp. ticks ... | 2009 | 20050009 |
| biological parameters of ticks (amblyomma cajennense fabricius, 1787) under field and laboratory conditions in pedro leopoldo, state of minas gerais, brazil. | this study evaluated the biological parameters of the duration of the pre-oviposition and egg incubation periods and maximum survival of unfed larvae, under field and laboratory conditions, with the aim of providing support for more rational measures for controlling amblyomma cajennense. this study was conducted at the experimental farm of the veterinary school of the federal university of minas gerais. every 14 days, from september 1997 to march 1998 and from october 1998 to april 1999, six net ... | 2008 | 20059808 |
| [ectoparasites of small wild mammals from the adjacent areas of itapecuru river and environmental preservation area of inhamum, state of maranhão, brazil]. | during fauna studies, thirty-six wild mammals were collected in adjacent areas of itapecuru river and environmental preservation area of inhamum, state of maranhão, brazil. they were sampled for ectoparasites. the following specimens of the order rodentia and its respective ectoparasites were identified: akodon sp. (androlaelaps sp. and laelaps sp.), oecomys sp. (androlaelaps sp. and amblyomma cajennense), oligoryzomys sp. (androlaelaps sp. laelaps sp. and amblyomma sp.) e oryzomys megacephalus ... | 2008 | 20059819 |
| [seasonal dynamics of the free-living stages of amblyomma cajennense and amblyomma dubitatum (acari: ixodidae) in an endemic area for spotted fever in coronel pacheco region, minas gerais state]. | a study on the population behavior of amblyomma cajennense and amblyomma dubitatum larvae, nymphs and adult free-living stages was carried out in coronel pacheco county, minas gerais state, brazil, a spotted feverendemic area from may 2006 to april 2008. larvae of amblyomma sp. were collected from pasture using the technique of drag sampling with flannelette during may to october 2006, starting from february 2007 to november 2007 and starting from march 2008. well-defined peaks of populations oc ... | 2008 | 20059821 |
| wide dispersal and possible multiple origins of low-copy-number plasmids in rickettsia species associated with blood-feeding arthropods. | plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. we report the existence of plasmids in rickettsia (rickettsiales; rickettsiaceae) species, including rickettsia akari, "candidatus rickettsia amblyommii," r. bellii, r. rhipicephali, and reis, the rickettsial endosymbiont of ixodes scapularis. all of the rickettsiae were isolated from humans or north and south american ticks. r. parkeri isolates from b ... | 2010 | 20097813 |
| detection of "candidatus rickettsia sp. strain argentina"and rickettsia bellii in amblyomma ticks (acari: ixodidae) from northern argentina. | ixodid ticks were collected from vegetation and from humans, wild and domestic mammals in a rural area in the semi-arid argentine chaco in late spring 2006 to evaluate their potential role as vectors of spotted fever group (sfg) rickettsiae. a total of 233 adult ticks, identified as amblyomma parvum, amblyomma tigrinum and amblyomma pseudoconcolor, was examined for rickettsia spp. we identified an sfg rickettsia of unknown pathogenicity, "candidatus rickettsia sp. strain argentina", in a. parvum ... | 2010 | 20186466 |
| biology and ecology of the brown dog tick, rhipicephalus sanguineus. | abstract: the brown dog tick (rhipicephalus sanguineus) is the most widespread tick in the world and a well-recognized vector of many pathogens affecting dogs and occasionally humans. this tick can be found on dogs living in both urban and rural areas, being highly adapted to live within human dwellings and being active throughout the year not only in tropical and subtropical regions, but also in some temperate areas. depending on factors such as climate and host availability, rh. sanguineus can ... | 2010 | 20377860 |
| repellent activity of deet against amblyomma cajennense (acari: ixodidae) nymphs submitted to different laboratory bioassays. | this study was developed to evaluate the repellent activity of n,n-diethyl-3-methylbenzamide (deet) against amblyomma cajennense nymphs. two repellent bioassays were compared and the effective concentration and repellent time were calculated. the fingertip test was accomplished to evaluate in vivo four concentrations of the compound (0.200; 0.100; 0.050 and 0.025 mg.cm⁻²) and the filter-paper bioassay to evaluate in vitro the two highest concentrations.the compound provided repellence higher tha ... | 2010 | 20385054 |
| experimental infection of the opossum didelphis aurita by rickettsia felis, rickettsia bellii, and rickettsia parkeri and evaluation of the transmission of the infection to ticks amblyomma cajennense and amblyomma dubitatum. | this work evaluated the infection of opossums (didelphis aurita) by rickettsia felis, rickettsia bellii, and rickettsia parkeri and their role as amplifier hosts for horizontal transmission to amblyomma cajennense and/or amblyomma dubitatum ticks. infection in d. aurita was induced by intraperitoneal inoculation with r. felis (n = 4 opossums), r. bellii (n = 4), and r. parkeri (n = 2). another group of six opossums were inoculated intraperitoneally with leibovitz-15 sterile culture medium, repre ... | 2010 | 20455783 |
| the expression of genes coding for distinct types of glycine-rich proteins varies according to the biology of three metastriate ticks, rhipicephalus (boophilus) microplus, rhipicephalus sanguineus and amblyomma cajennense. | ticks secrete a cement cone composed of many salivary proteins, some of which are rich in the amino acid glycine in order to attach to their hosts' skin. glycine-rich proteins (grps) are a large family of heterogeneous proteins that have different functions and features; noteworthy are their adhesive and tensile characteristics. these properties may be essential for successful attachment of the metastriate ticks to the host and the prolonged feeding necessary for engorgement. in this work, we an ... | 2010 | 20529354 |
| ticks (acari: ixodidae) on dogs from uberlândia, minas gerais, brazil. | uberlândia in minas gerais state, southeastern brazil, has 622 000 inhabitants and is located in the cerrado biome, the south american savannah. the city dog population is estimated at 82 000 and identification of tick species and infestation prevalence on this host has not been determined. a major infectious disease of dogs in the city, canine ehrlichiosis, is transmitted by rhipicephalus sanguineus ticks. at the same time, autochthonous leishmaniosis has been recently described in the city and ... | 2010 | 20537111 |
| innate immunity in wooless lamb to larvae of amblyomma cajennense tick (fabricius, 1787) (acari: ixodidae). | the cayenne tick amblyomma cajennense infests preferably horses in its adult form but other mammal species in its immature stages and is the main vector of rickettsia rickettsii, the brazilian spotted fever pathogen. as wooless lambs are often raised on pasture together with horses, an experiment was performed to investigate their possible acquisition of resistance to a. cajennense after experimental infestations. seven naïve wooless lambs were infested thrice at 60 days interval with immature a ... | 2010 | 20537112 |
| a new tick kunitz type inhibitor, amblyomin-x, induces tumor cell death by modulating genes related to the cell cycle and targeting the ubiquitin-proteasome system. | the aim of this study was to evaluate the anti-tumor activity of amblyomin-x, a serine protease kunitz-type inhibitor. amblyomin-x induced tumor mass regression and decreased number of metastatic events in a b16f10 murine melanoma model. alterations on expression of several genes related to cell cycle were observed when two tumor cell lines were treated with amblyomin-x. psmb2, which encodes a proteasome subunit, was differentially expressed, in agreement to inhibition of proteasomal activity in ... | 2010 | 20570593 |
| ultrastructure features of the midgut of the female adult amblyomma cajennense ticks fabricius, 1787 (acari: ixodidae) in several feeding stages and subjected to three infestations. | the digestive tract of amblyomma cajennense, as well as other species of ticks, is divided into the anterior, medium and posterior intestines and is the organ responsible for digestion of blood ingested during the meal on the host. the anterior and posterior regions are derived from the ectoderm and the medium one from the endoderm. in the present ultrastructural study, we analyzed the midgut of females in a semi- and fully engorged stages, on the rabbit host, which was subjected to three infest ... | 2010 | 20580564 |
| survey for tick-borne zoonoses in the state of espirito santo, southeastern brazil. | blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of espirito santo, brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were ... | 2010 | 20595502 |
| antigen-presenting cells in draining lymph nodes of goats repeatedly infested by the cayenne tick amblyomma cajennense nymphs. | resistance to tick feeding has been previously shown to be an acquired, immunologically mediated phenomenon in goats, associated with cutaneous basophilia to nymphs of amblyomma cajennense, the cayenne tick, after repeated infestations. on the other hand, it is well known that antigen-presenting cells (apcs) play an important role in the host immune reaction to tick infestations. the most able apcs for th cells are the well defined dendritic cells, mononuclear phagocytes and b-lymphocytes. immun ... | 2011 | 20596885 |
| acaricidal activity of the essential oils from eucalyptus citriodora and cymbopogon nardus on larvae of amblyomma cajennense (acari: ixodidae) and anocentor nitens (acari: ixodidae). | the present study evaluated the acaricidal activity of essential oils from eucalyptus citriodora and cymbopogon nardus on non-engorged larvae of amblyomma cajennense and anocentor nitens. in order to carry out the study, six groups were formed, each concentration being a treatment (6.25%, 12.5%, 25%, and 50%, respectively) and also with the creation of a control group (distilled water) and a positive control (deltametrine). for each treatment, approximately 100 larvae of these ticks were placed ... | 2010 | 20640444 |
| bm86 homologues and novel ataq proteins with multiple epidermal growth factor (egf)-like domains from hard and soft ticks. | tick control on livestock relies principally on the use of acaricides but the development of acaricide resistance and concerns for environmental pollution underscore the need for alternative control methods, for instance through the use of anti-tick vaccines. two commercial vaccines based on the recombinant bm86 protein from rhipicephalus (boophilus) microplus ticks were developed. partial protection of the bm86 vaccine against other rhipicephalus (boophilus) and hyalomma tick species suggests t ... | 2010 | 20647015 |
| amblyomma imitator ticks as vectors of rickettsia rickettsii, mexico. | real-time pcr of amblyomma imitator tick egg masses obtained in nuevo leon state, mexico, identified a rickettsia species. sequence analyses of 17-kd common antigen and outer membrane protein a and b gene fragments showed to it to be r. rickettsii, which suggested a potential new vector for this bacterium. | 2010 | 20678325 |
| secretory process of salivary glands of female amblyomma cajennense (acari: ixodidae) ticks fed on resistant rabbits. | ticks have great economic and health importance since infested animals have reduced milk and meat production, and, besides that, they are expensive ectoparasites to control. while feeding, ticks can transmit to their hosts a large amount of pathogens, including rickettsia rickettsii responsible for the "spotted fever" or "fever of the mountains." it is known that animals infested with ticks or artificially immunized with their salivary gland extracts develop resistance, which is related to a dec ... | 2011 | 20711802 |
| progress and obstacles in vaccine development for the ehrlichioses. | ehrlichia are tick-borne obligately intracellular bacteria that cause significant diseases in veterinary natural hosts, including livestock and companion animals, and are now considered important zoonotic pathogens in humans. vaccines are needed for these veterinary and zoonotic human pathogens, but many obstacles exist that have impeded their development. these obstacles include understanding genetic and antigenic variability, influence of the host on the pathogen phenotype and immunogenicity, ... | 2010 | 20822349 |
| new tick records in rondônia, western brazilian amazon. | in the present study, we provide new tick records from vilhena municipality, in the southeast of the state of rondônia, northern brazil. ticks collected from a capybara, hydrochoerus hydrochaeris (linnaeus), were identified as amblyomma romitii tonelli-rondelli (1 female), and amblyomma sp. (1 larva). ticks collected from a harpy eagle, harpia harpyja (linnaeus), were identified as amblyomma cajennense (fabricius) (16 nymphs) and haemaphysalis juxtakochi cooley (1 nymph). ticks collected from a ... | 2010 | 20943027 |
| rickettsial infections of dogs, horses and ticks in juiz de fora, southeastern brazil, and isolation of rickettsia rickettsii from rhipicephalus sanguineus ticks. | the present study was performed in an area endemic for brazilian spotted fever (bsf) in juiz de fora, state of minas gerais, brazil, during the years 2007 and 2008, when fatal cases of bsf (caused by rickettsia rickettsii) were reported. adult ticks (acari: ixodidae) identified as rhipicephalus sanguineus (latreille) and amblyomma cajennense (fabricius) were collected from dogs and horses, respectively, and tested by polymerase chain reaction (pcr). overall, 13.1% of the rh. sanguineus ticks and ... | 2010 | 20950356 |
| ticks (acari: ixodidae) infesting wild birds in the atlantic forest in northeastern brazil, with notes on rickettsial infection in ticks. | a total of 232 individuals representing 46 species of birds were mist-netted and screened for ticks in a region of the atlantic forest, state of bahia, brazil. thirty-eight (16.4%) of these birds representing 17 species were found infested by immature stages of amblyomma ticks, namely, amblyomma longirostre (koch, 1844) (15 larvae and seven nymphs), amblyomma nodosum (neumann, 1899) (nine nymphs), amblyomma calcaratum (neumann, 1899) (five nymphs), amblyomma cajennense (fabricius, 1787) (seven l ... | 2010 | 20953629 |
| biological differences between two allopatric populations of amblyomma cajennense (acari: ixodidae) in argentina. | the fertility of hybrids from two distinct populations of amblyomma cajennense from different ecological regions of northern argentina was analyzed. two colonies of a. cajennense from el rey national park (rnp), salta province (24º41's, 64º36'w), and copo national park (cnp), santiago del estero province (25º55's, 61º43'w) were established infesting rabbits with adults collected from vegetation. reproductive parameters of the first generation in laboratory of each colony and their crosses were e ... | 2010 | 20972702 |
| monitoring of resistance or susceptibility of adults and larvae of amblyomma cajennense (acari: ixodidae) to synthetic acaricides in goiás, brazil. | amblyomma cajennense or the cayenne tick is a three-host ixodid tick species of low parasitic specificity that is the principal vector of brazilian spotted fever. the primary objective of this study was to evaluate the possible development of resistance by adult specimens of a. cajennense to deltamethrin, a synthetic pyrethroid insecticide and the principal miticide/acaricide commercially available in the region. the second objective was to monitor the susceptibility and/or resistance of larvae ... | 2010 | 20976616 |
| rickettsia in synanthropic and domestic animals and their hosts from two areas of low endemicity for brazilian spotted fever in the eastern region of minas gerais, brazil. | the aim of this study was to understand the current epidemiology of rickettsial diseases in two rickettsial-endemic regions in brazil. in the municipalities of pingo d'agua and santa cruz do escalvado, among serum samples obtained from horses and dogs, reactivity by immunofluorescent assay against spotted fever group rickettsiae was verified. in some serum samples from opossums (didelphis aurita) captured in santa cruz do escalvado, serologic response against rickettsiae was also verified. polym ... | 2010 | 21118939 |
| ticks (acari: ixodidae) from yellow armadillo, euphractus sexcinctus (cingulata: dasypodidae), in brazil's pantanal wetlands. | tick species parasitizing yellow armadillo, euphractus sexcinctus, were recorded from october 2006 to october 2007 in pantanal. a total of 89 ticks were collected from 23 yellow armadillos. most ticks (n=50) were identified as amblyomma cajennense (fabricius) (32 males and 18 females). the only other species found was amblyomma parvum (aragão) (three females and two males). the remaining ticks were immatures of amblyomma (29 nymphs and five larvae). the prevalence of a. cajennense was 55%, the m ... | 2010 | 21120394 |
| rickettsial infection in domestic mammals and their ectoparasites in el valle de antón, coclé, panamá. | the present research evaluated the presence of rickettsia spp. on ectoparasites of horses and dogs (using pcr techniques), and their sera (using immunofluorescence assay) in el valle de antón town in panama. a total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks rhipicephalus sanguineus, amblyomma ovale, amblyomma oblongoguttatum, and the flea ctenocephalides felis), and two tick species on horses (amblyomma cajennense and dermacentor nitens). dna ... | 2010 | 21144663 |
| cross-mating experiments with geographically different populations of amblyomma cajennense (acari: ixodidae). | the present study evaluated the reproductive compatibility of the crosses between adult ticks of the following three geographically different populations of amblyomma cajennense: state of são paulo (sp), southeastern brazil; state of rondônia (ro), northern brazil; and colombia (co). in addition, crosses between a. cajennense ticks from argentina (ar) and sp ticks were also performed. the argentinean population (ar) was compatible with sp because their crosses resulted in high % egg hatching (me ... | 2011 | 21286933 |
| eschar-associated spotted fever rickettsiosis, bahia, brazil. | in brazil, brazilian spotted fever was once considered the only tick-borne rickettsial disease. we report eschar-associated rickettsial disease that occurred after a tick bite. the etiologic agent is most related to rickettsia parkeri, r. africae, and r. sibirica and probably widely distributed from sao paulo to bahia in the atlantic forest. | 2011 | 21291605 |
| salivary glands of amblyomma cajennense (acari: ixodidae): a histological and an ultrastructural overview. | the present study on the salivary glands of semi-engorged amblyomma cajennense females has identified the various cell types present in this tissue and allowed its morphohistochemical characterization. marking techniques were applied to detect polysaccharides (pas), proteins (bromophenol blue), lipids (nile blue) and calcium (von kossa), as well as those of scanning electron microscopy (sem) and transmission electron microscopy (tem). the results obtained by tem showed and confirmed that these i ... | 2011 | 21301932 |
| detection of theileria and babesia in brown brocket deer (mazama gouazoubira) and marsh deer (blastocerus dichotomus) in the state of minas gerais, brazil. | intraerythrocytic protozoan species of the genera theileria and babesia are known to infect both wild and domestic animals, and both are transmitted by hard-ticks of the family ixodidae. the prevalences of hemoprotozoa and ectoparasites in 15 free-living mazama gouazoubira, two captive m. gouazoubira and four captive blastocerus dichotomus from the state of minas gerais, brazil, have been determined through the examination of blood smears and the use of nested polymerase chain reaction (npcr). t ... | 2010 | 21354704 |
| failure of the amblyomma cajennense nymph to become infected by theileria equi after feeding on acute or chronically infected horses. | tick-borne diseases in horses are caused by the intraerythrocytic protozoan parasites theileria equi and babesia caballi. although t. equi is highly endemic in latin america, the new world vector of this important parasite is controversial. the aim of this study was to test the ability of nymph amblyomma cajennense ticks acquire infection by t. equi following feeding on infected horses. three experiments were performed: tick acquisition of t. equi from an experimentally infected horse, tick acqu ... | 2011 | 21501609 |
| experimental infection of amblyomma aureolatum ticks with rickettsia rickettsii. | we experimentally infected amblyomma aureolatum ticks with the bacterium rickettsia rickettsii, the etiologic agent of rocky mountain spotted fever (rmsf). these ticks are a vector for rmsf in brazil. r. rickettsii was efficiently conserved by both transstadial maintenance and vertical (transovarial) transmission to 100% of the ticks through 4 laboratory generations. however, lower reproductive performance and survival of infected females was attributed to r. rickettsii infection. therefore, bec ... | 2011 | 21529391 |
| coxiella symbionts in the cayenne tick amblyomma cajennense. | members of the coxiella genus are intracellular bacteria that can infect a variety of animals including humans. a symbiotic coxiella was recently described in amblyomma americanum ticks in the northern hemisphere with no further investigations of other amblyomma species in other geographic regions. these ixodid ticks represent a group of important vectors for human infectious agents. in the present work, we have demonstrated that symbiotic coxiella (scox) are widespread, occurring in south ameri ... | 2011 | 21611689 |
| tick-borne bacteria in free-living jaguars (panthera onca) in pantanal, brazil. | abstract tick-borne bacteria were investigated in 10 free-living jaguars and their ticks in the pantanal biome, brazil. jaguar sera were tested by indirect fluorescent antibody assays using rickettsia rickettsii, rickettsia parkeri, rickettsia amblyommii, rickettsia rhipicephali, rickettsia felis, rickettsia bellii, ehrlichia canis, and coxiella burnetii as crude antigens. all 10 jaguar sera reacted (titer ≥64) to at least one rickettsia species; 4 and 3 sera reacted with e. canis and c. burneti ... | 2011 | 21612532 |
| first report of the isolation and molecular characterization of rickettsia amblyommii and rickettsia felis in central america. | abstract during 2010, 15 adult ticks, identified as amblyomma cajennense, were collected from horses in cahuita and turrialba districts, whereas 7 fleas, identified as ctenocephalides felis, were collected from a dog in san jose city, costa rica. in the laboratory, three a. cajennense specimens, two from cahuita and one from turrialba, were individually processed for rickettsial isolation in cell culture, as was a pool of seven fleas. rickettsiae were successfully isolated and established in ver ... | 2011 | 21612539 |
| meteorological indicators for amblyomma cajennense and population dynamics in the tamaulipan biotic province in texas. | we studied the population dynamics of free-living ticks in the tamaulipan biotic province in south texas from march, 2005 to november, 2008. we collected 70,873 ticks using carbon dioxide traps. amblyomma cajennense represented 93.6% of the ticks identified. a. cajennense is distributed from northern argentina to south texas in the tamaulipan biotic province. emergence of larval a. cajennense ticks was observed two to five weeks after significant rain events (p<0.0001) and had a strong negative ... | 2011 | 21635651 |
| acaricidal activity of thymol on larvae and nymphs of amblyomma cajennense (acari: ixodidae). | the aim of the present study was to evaluate the acaricidal efficacy of thymol on unengorged and engorged larvae and engorged nymphs of amblyomma cajennense. to perform the test for unengorged larvae, the larval packet technique was employed and mortality was evaluated 24h after the test, while for engorged larvae and engorged nymphs the immersion technique was employed and mortality was evaluated after 15 days. in all the experiments, the following concentrations of thymol were tested: 2.5, 5.0 ... | 2011 | 21794986 |
| organic parasite control for poultry and rabbits in british columbia, canada. | abstract: plants used for treating endo- and ectoparasites of rabbits and poultry in british columbia included arctium lappa (burdock), artemisia sp. (wormwood), chenopodium album (lambsquarters) and c. ambrosioides (epazote), cirsium arvense (canada thistle), juniperus spp. (juniper), mentha piperita (peppermint), nicotiana sp. (tobacco), papaver somniferum (opium poppy), rubus spp. (blackberry and raspberry relatives), symphytum officinale (comfrey), taraxacum officinale (common dandelion), th ... | 2011 | 21756341 |
| infection by spotted fever rickettsiae in people, dogs, horses and ticks in londrina, parana state, brazil. | spotted fever is a disease caused by bacteria from the genus rickettsia of the spotted fever group (sfg). rickettsia rickettsii is likely the main agent of brazilian spotted fever (bsf). with the objective of gathering information on the circulation of sfg rickettsiae in londrina, parana state, ticks from dogs and horses and also blood from dogs, horses and humans were collected in a neighbourhood of the city which presented potential for circulation of rickettsiae between hosts and vectors. amb ... | 2011 | 21824336 |
| the action of amblyomma cajennense tick saliva in compounds of the hemostatic system and cytotoxicity in tumor cell lines. | ticks are blood-feeding arthropods that secrete anticoagulant molecules to maintain the fluidity of the blood during its feeding. tick saliva has many compounds with biological activities that interact directly with host systems, such as blood clotting, platelet aggregation, cell death, among others. some reports show that there are proteins with anticancer properties in tick saliva. this paper reports some of the biological roles of the amblyomma cajennense tick saliva, including factor xa and ... | 2011 | 21723081 |
| induction of complete courtship ritual in amblyomma cajennense using 2,6-dichlorophenol at female-equivalent quantities. | in order to clarify the role of 2,6-dichlorophenol (2,6-dcp) in the courtship of amblyomma cajennense, sexually mature males that had previously fed on rabbits were tested in bioassays. the males were released onto dummies treated with whole female extract or synthetic 2,6-dcp at a concentration of two female equivalents, or with hexane (control), and their responses were observed. in the presence of both the extract and 2,6-dcp, excitation was observed among the males, expressed in the form of ... | 2011 | 22166393 |
| An insight into the sialotranscriptome and proteome of the coarse bontlegged tick, Hyalomma marginatum rufipes. | Ticks are mites specialized in acquiring blood from vertebrates as their sole source of food and are important disease vectors to humans and animals. Among the specializations required for this peculiar diet, ticks evolved a sophisticated salivary potion that can disarm their host's hemostasis, inflammation, and immune reactions. Previous transcriptome analysis of tick salivary proteins has revealed many new protein families indicative of fast evolution, possibly due to host immune pressure. The ... | 2011 | 21851864 |
| a novel rickettsia infecting amblyomma dubitatum ticks in brazil. | a total of 130 adult free-living ticks of amblyomma cajennense and 9 free-living amblyomma dubitatum were collected in the surroundings of the pampulha lake, within belo horizonte city, state of minas gerais, south-eastern brazil. each adult tick was tested for rickettsial infection by pcr protocols targeting the rickettsial genes glta, htra, and ompa. all the 130 a. cajennense ticks were negative by pcr. in contrast, all 9 a. dubitatum ticks were shown to contain rickettsial dna. pcr products w ... | 2011 | 22108014 |
| rickettsia species infecting amblyomma ticks from an area endemic for brazilian spotted fever in brazil. | this study reports rickettsial infection in amblyomma cajennense and amblyomma dubitatum ticks collected in an area of the state of minas gerais, brazil, where brazilian spotted fever is considered endemic. for this purpose, 400 adults of a. cajenennse and 200 adults of a. dubitatum, plus 2,000 larvae and 2,000 nymphs of amblyomma spp. were collected from horses and from the vegetation. the ticks were tested for rickettsial infection through polymerase chain reaction (pcr) protocols targeting po ... | 2011 | 22166385 |
| [surveillance of rickettsia sp. infection in capybaras (hydrochoerus hydrochaeris) a potential model of epidemiological alert in endemic areas]. | introduction. capybaras (hydrochoerus hydrochaeris) are considered amplifying hosts of rickettsia sp. these rodents are usually parasitized by the tick vector, amblyomma cajennense, the main vector of rickettsioses in humans and animals in south america. capybaras can be used as sentinels in detection of circulation of rickettsiae. objective. antibodies to rickettsiae of spotted fever group were detected in capybaras in a rural area of cordoba province, northern colombia. materials and methods. ... | 2011 | 22159538 |
| distribution of rickettsia rickettsii in ovary cells of rhipicephalus sanguineus (latreille1806) (acari: ixodidae). | abstract: | 2011 | 22117572 |
| experimental infection of the tick amblyomma cajennense, cayenne tick, with rickettsia rickettsii, the agent of rocky mountain spotted fever. | in the laboratory, amblyomma cajennense (acari: ixodidae) (fabricius) larvae, nymphs and adults were exposed to rickettsia rickettsii by feeding on needle-inoculated animals, and thereafter reared on uninfected guinea pigs or rabbits. regardless of the tick stage that acquired the infection, subsequent tick stages were shown to be infected (confirming transstadial and transovarial transmissions) and were able to transmit r. rickettsii to uninfected animals, as demonstrated by serological and mol ... | 2011 | 22007869 |
| factors associated to theileria equi in equids of two microregions from rio de janeiro, brazil. | serum samples from 714 equids of itaguaí and serrana microregions, rio de janeiro, southeastern brazil, were examined by indirect fluorescent antibody test (titer 1:80) for theileria equi. the prevalence in the microregions and factors associated with seropositivity were evaluated and the prevalence ratio (pr) calculated. the overall prevalence of t. equi infection was 81.09% (n = 579), with higher prevalence (p < 0.05) in the itaguaí (85.43%) when compared to serrana microregion (76.92%). the g ... | 2011 | 21961755 |