| serum basophil-stimulating activity in the guinea-pig during induction of basophilic responses to ovalbumin and tick feeding. | we have described functional and biochemical characteristics of a distinct t-cell dependent guinea-pig basophil-stimulating factor (bsf), measured using a sensitive 7-day bone marrow culture assay, standardized with high-activity bsf present in serum-free splenic cell-conditioned medium (cm). in the present studies, the in vivo relevance of bsf was explored during protocols of induction of peripheral blood or tissue basophil responses to ovalbumin (oa) injection or amblyomma americanum tick feed ... | 1986 | 3733145 |
| resistance to ixodid tick infestation induced by administration of tick-tissue culture cells. | primary tissue culture cells of developing larvae of amblyomma americanum were administered to guinea-pigs never previously exposed to ixodid ticks. guinea-pigs were given 1 x 10(6) primary culture cells on days 0, 7 and 21 by subcutaneous injection and challenged with male and female a. americanum on day 35. a significant degree of induced host tick resistance was expressed by reduced engorgement weight of females, reduced oviposition by those females which did obtain a blood meal, and by death ... | 1985 | 4083961 |
| effect of host age on the expression of acquired resistance to ticks. | young guinea-pigs (350 g) expressed significantly greater levels of acquired resistance to challenge by larval amblyomma americanum ticks than older guinea-pigs (520-800 g). this finding suggests that younger guinea-pigs are immunologically more responsive to tick infestation than older mature individuals. therefore, host age is an important variable in evaluating acquired resistance to ticks. | 1984 | 6698176 |
| ixodid ticks on feral swine in florida. | more than 99% of the 645 feral swine (sus scrofa l.) in southern florida harbored ixodid ticks. dermacentor variabilis (american dog tick) was present on 99.6% of the swine and comprised 82.5% of the ticks collected. amblyomma maculatum (gulf coast tick) occurred on 85.9% of the hosts and 17.4% of the collections were of this species. amblyomma americanum (lone star tick) and ixodes scapularis (black-legged tick) were found infrequently and together constituted less than 0.1% of the ticks. pigs ... | 1984 | 6737605 |
| regulation of feeding and ovipositional success of amblyomma americanum ticks. | | 1982 | 7128750 |
| ixodid ticks on white-tailed deer and feral swine in florida. | a state-wide survey was conducted in florida during the 1997-99 hunting seasons to examine white-tailed deer (odocoileus virginianus) and feral swine (sus scrofa) for potential indigenous vectors of the rickettsial agent of heartwater, cowdria ruminantium. a total of 504 white-tailed deer and 166 feral swine was examined from 30 wildlife management areas across the state. amblyomma maculatum, an experimental vector of c. ruminantium, was common on both deer and feral swine throughout the state. ... | 2001 | 11469190 |
| analysis of serum and whole blood values in relation to helminth and ectoparasite infections of feral pigs in texas. | in the summers of 1996 and 1997, 60 wild pigs (sus scrofa) were necropsied from three sites in south texas (usa) to test the hypothesis that serum and whole blood parameters vary significantly (p < or = 0.05) with the prevalence and intensity of parasites infecting wild pigs. we found ten parasite species: five nematodes (metastrongylus salmi, metastrongylus pudentotectus, stephanurus dentatus, oesophagostomum dentatum, and physocephalus sexalatus); four ixodid ticks (amblyomma cajennense, ambly ... | 2002 | 12038138 |
| a critical analysis of disease-associated dna polymorphisms in the genes of cattle, goat, sheep, and pig. | genetic variations through their effects on gene expression and protein function underlie disease susceptibility in farm animal species. the variations are in the form of single nucleotide polymorphisms, deletions/insertions of nucleotides or whole genes, gene or whole chromosomal rearrangements, gene duplications, and copy number polymorphisms or variants. they exert varying degrees of effects on gene action, such as substitution of an amino acid for another, shift in reading frame and prematur ... | 2008 | 18350334 |
| a leishmania ortholog of macrophage migration inhibitory factor modulates host macrophage responses. | parasitic organisms have evolved specialized strategies to evade immune defense mechanisms. we describe herein an ortholog of the cytokine, macrophage migration inhibitory factor (mif), which is produced by the obligate intracellular parasite, leishmania major. the leishmania mif protein, lm1740mif, shows significant structural homology with human mif as revealed by a high-resolution x-ray crystal structure (1.03 a). differences between the two proteins in the n-terminal tautomerization site are ... | 2008 | 18523291 |
| evidence of the importance of host habitat use in predicting the dilution effect of wild boar for deer exposure to anaplasma spp. | foci of tick-borne pathogens occur at fine spatial scales, and depend upon a complex arrangement of factors involving climate, host abundance and landscape composition. it has been proposed that the presence of hosts that support tick feeding but not pathogen multiplication may dilute the transmission of the pathogen. however, models need to consider the spatial component to adequately explain how hosts, ticks and pathogens are distributed into the landscape. in this study, a novel, lattice-deri ... | 2008 | 18714379 |
| 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. | 2008 | 19021911 |
| current management of human granulocytic anaplasmosis, human monocytic ehrlichiosis and ehrlichia ewingii ehrlichiosis. | anaplasma phagocytophilum, ehrlichia chaffeensis and ehrlichia ewingii are emerging tick-borne pathogens and are the causative agents of human granulocytic anaplasmosis, human monocytic ehrlichiosis and e. ewingii ehrlichiosis, respectively. collectively, these are referred to as human ehrlichioses. these obligate intracellular bacterial pathogens of the family anaplasmataceae are transmitted by ixodes spp. or amblyomma americanum ticks and infect peripherally circulating leukocytes to cause inf ... | 2009 | 19681699 |
| blood meal analysis to identify reservoir hosts for amblyomma americanum ticks. | efforts to identify wildlife reservoirs for tick-borne pathogens are frequently limited by poor understanding of tick-host interactions and potentially transient infectivity of hosts under natural conditions. to identify reservoir hosts for lone star tick (amblyomma americanum)-associated pathogens, we used a novel technology. in field-collected ticks, we used pcr to amplify a portion of the 18s rrna gene in remnant blood meal dna. reverse line blot hybridization with host-specific probes was th ... | 2010 | 20202418 |
| crystal structure and functional characterization of an immunomodulatory salivary cystatin from the soft tick ornithodoros moubata. | the saliva of blood-feeding parasites is a rich source of peptidase inhibitors that help to overcome the host's defence during host-parasite interactions. using proteomic analysis, the cystatin omc2 was demonstrated in the saliva of the soft tick ornithodoros moubata, an important disease vector transmitting african swine fever virus and the spirochaete borrelia duttoni. a structural, biochemical and biological characterization of this peptidase inhibitor was undertaken in the present study. rec ... | 2010 | 20545626 |
| anaplasma phagocytophilum--a widespread multi-host pathogen with highly adaptive strategies. | the bacterium anaplasma phagocytophilum has for decades been known to cause the disease tick-borne fever (tbf) in domestic ruminants in ixodes ricinus-infested areas in northern europe. in recent years, the bacterium has been found associated with ixodes-tick species more or less worldwide on the northern hemisphere. a. phagocytophilum has a broad host range and may cause severe disease in several mammalian species, including humans. however, the clinical symptoms vary from subclinical to fatal ... | 2013 | 23885337 |
| geographical distribution of amblyomma cajennense (sensu lato) ticks (parasitiformes: ixodidae) in brazil, with description of the nymph of a. cajennense (sensu stricto). | until recently, amblyomma cajennense (fabricius, 1787) was considered to represent a single tick species in the new world. recent studies have split this taxon into six species. while the a. cajennense species complex or a. cajennense (sensu lato) (s.l.) is currently represented by two species in brazil, a. cajennense (sensu stricto) (s.s.) and amblyomma sculptum berlese, 1888, their geographical distribution is poorly known. | 2016 | 27036324 |
| amblyomma cajennense (fabricius, 1787) (acari: ixodidae), the cayenne tick: phylogeography and evidence for allopatric speciation. | amblyomma cajennense f. is one of the best known and studied ticks in the new world because of its very wide distribution, its economical importance as pest of domestic ungulates, and its association with a variety of animal and human pathogens. recent observations, however, have challenged the taxonomic status of this tick and indicated that intraspecific cryptic speciation might be occurring. in the present study, we investigate the evolutionary and demographic history of this tick and examine ... | 2013 | 24320199 |
| age-dependent expression of stress and antimicrobial genes in the hemocytes and siphon tissue of the antarctic bivalve, laternula elliptica, exposed to injury and starvation. | increasing temperatures and glacier melting at the western antarctic peninsula (wap) are causing rapid changes in shallow coastal and shelf systems. climate change-related rising water temperatures, enhanced ice scouring, as well as coastal sediment runoff, in combination with changing feeding conditions and microbial community composition, will affect all elements of the nearshore benthic ecosystem, a major component of which is the antarctic soft-shelled clam laternula elliptica. a 454-based r ... | 2013 | 23666709 |
| a crayfish insulin-like-binding protein: another piece in the androgenic gland insulin-like hormone puzzle is revealed. | across the animal kingdom, the involvement of insulin-like peptide (ilp) signaling in sex-related differentiation processes is attracting increasing attention. recently, a gender-specific ilp was identified as the androgenic sex hormone in crustacea. however, moieties modulating the actions of this androgenic insulin-like growth factor were yet to be revealed. through molecular screening of an androgenic gland (ag) cdna library prepared from the crayfish cherax quadricarinatus, we have identifie ... | 2013 | 23775079 |