Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| babesia bovis immunity. in vitro and in vivo evidence for il-10 regulation of ifn-gamma and inos. | il-10 has been shown to have profound immunoregulatory attributes and in the bovine appears to downregulate both th1- and th2-like responses. using rt-pcr, we demonstrate il-10 in vitro down-regulation of mrna expression of inos, the cytokines involved in nitric oxide signal transduction initiation (ifn-gamma and tnf-alpha), and other mononuclear phagocyte associate cytokines. in addition, using rt-pcr with peripheral blood leukocytes and spleen leukocytes, the griess reaction, and a killing ass ... | 1998 | 9668462 |
| bovine babesiosis. seroprevalence and ticks associated with cattle from two different regions of morocco. | a total of 475 bovine sera collected in 1995-1996 from 10 areas belonging to two different bioclimatic strata were tested for antibody activity to babesia bigemina and babesia bovis using indirect immunofluorescence (iif). in the gharb, the b. bovis seroprevalence was 21.7% and for b. bigemina, 10.8%. the infection rate for either or both species as determined microscopically with giemsa-stained blood films was 18.9%. the tiflet area was considered an endemic focus, and the seroprevalence was 42 ... | 1998 | 9668467 |
| evaluation of a frozen trivalent attenuated vaccine against babesiosis and anaplasmosis in brazil. | 1998 | 9668502 | |
| identification of babesia bovis antigens by monoclonal antibodies. | 1998 | 9668505 | |
| use of monoclonal antibodies for the identification of a common surface antigen of babesia bovis. | 1998 | 9668506 | |
| antigenic variation in babesia bovis: how similar is it to that in plasmodium falciparum? | despite significant differences in some aspects of their life-cycles, the apicomplexan parasites babesia bovis and plasmodium falciparum share many parallels. significant among these are participation in rapid, clonal antigenic variation, and cyto-adherence and sequestration in the deep vasculature. antigenic variation has long been thought to be primarily a mechanism of escape from antibody-mediated mechanisms of the host's immune system. in each species, the components demonstrated to particip ... | 1998 | 9683897 |
| immunodominant t-cell antigens and epitopes of babesia bovis and babesia bigemina. | despite convincing evidence that t cells are critical for both cellular and humoral immunity against haemoprotozoan parasites, the difficulty of performing meaningful experiments in cattle that would define the role of t cells in immunity to babesia spp. has impeded research in this area. however, experiments performed ex vivo with immune t cells can reflect in-vivo events, and provide valuable insight into the nature of immunogenic proteins and the responding lymphocytes. the progress made towa ... | 1998 | 9683898 |
| parasite localization and dissemination in the babesia-infected host. | babesia bovis infections in cattle and b. canis infections in dogs are characterized by non-haemolytic anaemia and low parasitaemia during the acute phase of the disease. in this phase of the disease, animals suffer from hypotension followed by disturbances of the coagulation system. this review discusses the hypothesis that may explain the process of parasite localization in the host, and the consequences of such localization. it is suggested that hypotension favours the interaction between inf ... | 1998 | 9683902 |
| [investigation of babesia in farm workers and blood donors in the province of ciego de avila]. | a descriptive study of cases was conducted in which 781 sera were investigated using the indirect immunofluorescent technique with antigens of babesia bovis and babesia bigemina at the national center for agricultural health. of them, 371 came from agricultural workers and 410 from donors in the province of ciego de avila. it was started from dilutions of 1/64. an epidemiological survey was done to each seropositive so as to know the risk factors. the test of difference of proportions was used t ... | 1997 | 9685976 |
| stimulation of nitric oxide production in macrophages by babesia bovis. | gamma interferon (ifn-gamma)-activated macrophages are believed to play a key role in resistance to babesia bovis through parasite suppression by macrophage secretory products. however, relatively little is known about interactions between this intraerythrocytic parasite and the macrophages of its bovine host. in this study, we examined the in vitro effect of intact and fractionated b. bovis merozoites on bovine macrophage nitric oxide (no) production. in the presence of ifn-gamma, b. bovis mero ... | 1998 | 9712758 |
| bovine babesiosis in dual purpose calves in the state of yucatan, mexico. | thirty-eight dual purpose calves in the 3 agricultural zones of the state of yucatan, mexico were monitored for antibodies to babesia bovis and b. bigemina from close to birth up to 12 months of age. the results showed that infection with both parasites is widespread throughout the 3 zones. many of the animals had produced antibody to both parasites by 6 months of age indicating high transmission rates resulting in enzootic stability for both parasites. any changes to agricultural practices in t ... | 1998 | 9719829 |
| amelioration of virulent babesia bovis infection in calves by administration of the nitric oxide synthase inhibitor aminoguanidine. | calves undergoing initial infection with a virulent strain of the haemoprotozoan parasite babesia bovis were treated with aminoguanidine (ag), an inhibitor of the inducible form of nitric oxide synthase (inos). the mean maximum parasitaemia of the ag treated calves was significantly lower than that of the control cattle. in addition, the febrile response and decrease in packed cell volume (pcv) observed during acute infection were significantly ameliorated in the ag treated cattle relative to th ... | 1998 | 9767611 |
| sequence and functional analysis of the intergenic regions separating babesial rhoptry-associated protein-1 (rap-1) genes. | the rhoptry-associated protein 1 (rap-1) expressed by all babesial parasites is encoded by tandemly arranged genes separated by discrete intergenic (ig) regions. we hypothesize that these ig regions regulate rap-1 gene expression. in babesia bovis two identical rap-1 gene copies are separated by a 1.0-kb noncoding region which is also exactly conserved 5' to the rap-1 gene 1. in contrast, the complex b. bigemina rap-1 locus contains at least 5 polymorphic rap-1a genes separated by uncharacterize ... | 1998 | 9769249 |
| dna and a cpg oligonucleotide derived from babesia bovis are mitogenic for bovine b cells. | dnas from bacteria and variety of nonvertebrate organisms, including nematodes, mollusks, yeasts, and insects, cause polyclonal activation of murine b lymphocytes. similar studies have not been reported for bovine b cells, and to date no studies have reported mitogenic properties of protozoal dna for any species. however, we and others have observed that protozoal parasite antigens can induce the proliferation of lymphocytes from nonexposed donors. extending these studies, we now show that the m ... | 1998 | 9784553 |
| the absence of clinical disease in cattle in communal grazing areas where farmers are changing from an intensive dipping programme to one of endemic stability to tick-borne diseases. | a two-year field study was conducted in four communal grazing areas in south africa. sera were collected from young cattle (6-18 months old) in these areas during the winters of 1991 to 1993. the sera were tested for antibodies to babesia bovis, babesia bigemina, anaplasma marginale and cowdria ruminantium. in two of the four areas, treatment with acaricide was erratic and dependent on the discretion of individual owners. in these areas the drought of 1992 had a major impact on tick burdens and ... | 1998 | 9809321 |
| seroprevalence of babesia ovis in sheep in catalonia, northeastern spain. | an indirect fluorescent antibody test (ifat) was developed in order to detect antibodies against babesia ovis in different sheep flocks from catalonia, northeastern spain. of the total 2174 sera included in the study, 133 (6.1%) were positive. considerable differences in seroprevalence were detected depending on the geographical areas from which the animals originated. this must have been a consequence of the presence or absence of the vector tick, rhipicephalus bursa, the distribution of which ... | 1998 | 9831951 |
| seroprevalence of babesia ovis in goats in catalonia, spain. | 1998 | 9839368 | |
| babesia bovis: common protein fractions recognized by oligoclonal b. bovis-specific cd4+ t cell lines from genetically diverse cattle. | cd4+ helper t cells are believed to be important for inducing protective immunity against babesia bovis through the production of cytokines, including ifn-gamma, that will provide help to b lymphocytes for igg production and activate macrophages to become parasiticidal. to provide maximum protection in an outbred population, an effective vaccine against b. bovis should contain antigens that would elicit an ifn-gamma response and would be recognized by cattle with diverse genetic backgrounds. to ... | 1999 | 9920041 |
| upregulation of interleukin-4 and ifn-gamma expression by ifn-tau, a member of the type i ifn family. | trophoblast interferon-tau (ifn-tau) is a new member of the type i ifn family that is produced in large quantities by the ruminant conceptus. like other type i ifn, ifn-tau inhibits viral replication and activates natural killer (nk)-mediated cytotoxicity. in mice and humans, type i ifn enhances type 1 t helper (th) cell responses, but the effects of type i ifn, including ifn-tau, on cytokine expression by bovine th cells have not been described. the present study determined the effects of ifn-t ... | 1999 | 10090403 |
| epidemiology of tick-borne diseases of cattle in botshabelo and thaba nchu in the free state province. | a seroepidemiological study was conducted on 151 cattle from the botshabelo and thaba nchu areas in the central free state province of south africa, two areas where small scale, peri-urban cattle farming is practised. an indirect fluorescent antibody test was used to test for babesia bigemina and b. bovis antibodies. to test for anaplasma marginale antibodies a competitive inhibition enzyme-linked immunosorbent assay method was used. there were no significant differences in serological test resu ... | 1998 | 10192841 |
| vaccines against bovine babesiosis--longest field trial? | 1999 | 10197254 | |
| development and evaluation of an extra chromosomal dna-based pcr test for diagnosing bovine babesiosis. | subclinical infections of bovine babesiosis, caused primarily by babesia bigemina or babesia bovis are a challenge to current diagnostic methods. in this study, the development and evaluation of a pcr test for sensitive and specific detection of b. bigemina or b. bovis is described. the target selected for amplification is part of the apocytochrome b gene, conserved in both babesia spp. and located on the linear approximately 6.0 kb extra chromosomal dna. the test was evaluated to detect the par ... | 1999 | 10208801 |
| detection of igm antibodies against babesia bovis in cattle. | the diagnosis of acute babesiosis by direct examination of blood smears has some limitations and the indirect serological methods currently in use are designed for detection of igg, which may not be detectable at an early stage of infection. there is a need, therefore, for rapid and reliable procedures to diagnose acute infections. an elisa system using a crude antigenic preparation of babesia bovis was standardized for the detection of igm antibodies. optimal dilutions of the antigen, using pos ... | 1999 | 10223346 |
| comparison of cattle responses to mono-specific or combined inoculations with babesia bigemina and babesia bovis vaccine strains. | combined inoculation of cattle with vaccine strains of babesia bigemina and babesia bovis induced lower antibody titers to b. bigemina than to b. bovis (previous study). three groups of heifers were used to detect if the low antibody level was due to competition between babesia species: individuals of g1 and g2 were inoculated with 10 million b. bigemina and b. bovis, respectively, and those of g3 with 10 million of each parasite. the prepatent periods, maximum parasitaemias and antibody titers ... | 1999 | 10229940 |
| simultaneous detection of bovine theileria and babesia species by reverse line blot hybridization. | a reverse line blot (rlb) assay was developed for the identification of cattle carrying different species of theileria and babesia simultaneously. we included theileria annulata, t. parva, t. mutans, t. taurotragi, and t. velifera in the assay, as well as parasites belonging to the t. sergenti-t. buffeli-t. orientalis group. the babesia species included were babesia bovis, b. bigemina, and b. divergens. the assay employs one set of primers for specific amplification of the rrna gene v4 hypervari ... | 1999 | 10325324 |
| selection and recovery of minor parasite populations expressing unique infected-erythrocyte phenotypes. | 1999 | 10377000 | |
| designing blood-stage vaccines against babesia bovis and b. bigemina. | the tick-transmitted apicomplexan parasites babesia bovis and b. bigemina cause significant disease in cattle in many tropical and temperate areas of the world. these parasites present a challenge for vaccine development, and yet provide a system for studying the pathogenesis, mechanisms of protective immunity and regulation of host immune responses associated with intraerythrocytic protozoan parasites in a non-rodent species. in this article, wendy brown and guy palmer review strategies for ide ... | 1999 | 10377530 |
| cytoadherence of babesia bovis-infected erythrocytes to bovine brain capillary endothelial cells provides an in vitro model for sequestration. | babesia bovis, an intraerythrocytic parasite of cattle, is sequestered in the host microvasculature, a behavior associated with cerebral and vascular complications of this disease. despite the importance of this behavior to disease etiology, the underlying mechanisms have not yet been investigated. to study the components involved in sequestration, b. bovis parasites that induce adhesion of the infected erythrocytes (irbcs) to bovine brain capillary endothelial cells (bbec) in vitro were isolate ... | 1999 | 10417157 |
| management factors associated with babesia bovis seroprevalence in cattle from eastern yucatán, mexico. | the effect of management on the seroprevalence of babesia bovis was studied in 399 bos indicus cattle 1-2 years old from 92 farms in the eastern yucatán, méxico. the management factors studied were: farm-type, production system, herd size, farm size, stocking density, vector control, dipping interval, type of dipping, type of acaricide and cattle introduction to the farm. a cross-sectional study was carried out (2-stage cluster sampling). the number of serum samples was proportionally distribute ... | 1999 | 10423779 |
| effect of breed of cattle on transmission rate and innate resistance to infection with babesia bovis and b bigemina transmitted by boophilus microplus. | to assess the effect of breed of cattle on the transmission rates of and innate resistance to babesia bovis and b bigemina parasites transmitted by boophilus microplus ticks. | 1999 | 10451733 |
| comparative effects of interleukin-12 and interleukin-4 on cytokine responses by antigen-stimulated memory cd4+ t cells of cattle: il-12 enhances ifn-gamma production, whereas il-4 has marginal effects on cytokine expression. | interleukin-12 (il-12) and il-4 are important immunoregulatory cytokines that determine the fate of naive t cells during antigen priming in mice and also influence cytokine synthesis by differentiated murine and human t cells. the roles of these cytokines in regulating the differentiation and effector function of bovine t cells are less well studied. we investigated the ability of human il-12 and bovine il-4 to modify cytokine expression by antigen-stimulated t cells from cattle immune to the pr ... | 1999 | 10454344 |
| can babesia infections be used as a model for cerebral malaria? | infections with certain species of plasmodium and babesia induce, among other symptoms, cerebral pathology. the finding of heavily parasitized cerebral capillaries upon postmortem examination has led to the assumption that blockage of capillaries with infected red blood cells caused the cerebral symptoms and subsequent death. as this type of cerebrovascular pathology is found both in humans dying from malaria and in cattle dying from babesiosis, the latter could possibly be used as an animal mod ... | 1999 | 10557150 |
| transmission of babesia spp by the cattle tick (boophilus microplus) to cattle treated with injectable or pour-on formulations of ivermectin and moxidectin. | to assess the efficacy of ivermectin and moxidectin to prevent transmission of babesia bovis and babesia bigemina by boophilus microplus to cattle under conditions of relatively intense experimental challenge. | 1999 | 10590793 |
| a unique babesia bovis spherical body protein is conserved among geographic isolates and localizes to the infected erythrocyte membrane. | using monoclonal antibody (mab) 70/52.9, generated from a babesia bovis fraction enriched for spherical body organelles, we have identified a 135-kda protein containing an epitope conserved in b. bovis strains from texas, mexico, and australia. the protein was localized to the spherical bodies of the babesial apical complex and was designated spherical body protein 3 (sbp3), according to the established nomenclature. immunofluorescence studies showed binding of the 70/52.9 mab to the infected-er ... | 2000 | 10613694 |
| modulation of host immune responses by protozoal dna. | the pathology caused by acute babesia bovis infection is similar to that seen in severe human malaria caused by plasmodium falciparum infection, which is related to dysregulated production of inflammatory cytokines and nitric oxide (no). we have observed induction of no, inducible nitric oxide synthase (inos) and inflammatory cytokines in macrophages by b. bovis. furthermore, proliferation of lymphocytes from individuals never exposed to certain protozoal pathogens can be induced by crude protoz ... | 1999 | 10614497 |
| selection of babesia bovis-infected erythrocytes for adhesion to endothelial cells coselects for altered variant erythrocyte surface antigen isoforms. | sequestration of babesia bovis-infected erythrocytes (irbcs) in the host microvasculature is thought to constitute an important mechanism of immune evasion. since ig is considered to be important for protection from disease, an in vitro assay of b. bovis sequestration was used to explore the ability of anti-b. bovis ig to interfere with irbc cytoadhesion, and to identify irbc surface ags acting as endothelial cell receptors. bovine infection sera reactive with the irbc surface inhibited and even ... | 2000 | 10657656 |
| a common high molecular weight antigen of babesia bovis isolates from mexico. | cattle from an area of mexico endemic with babesia bovis infections have a dominant antibody response to a 152kda antigen of the tamaulipas strain of b. bovis. a mab termed pb/5, showing a specific reactivity to this 152kda antigen in western blots, was identified. the mab which reacted with the blunt end of b. bovis in an indirect fluorescent antibody test also reacted to a 152kda antigen in two other isolates (nuevo leon and yucatan), and a 175kda antigen in the huasteca b. bovis isolate from ... | 2000 | 10675745 |
| the ves multigene family of b. bovis encodes components of rapid antigenic variation at the infected erythrocyte surface. | b. bovis, an intraerythrocytic protozoal parasite, establishes chronic infections in cattle in part through rapid variation of the polymorphic, heterodimeric vesa1 protein on the infected erythrocyte surface and sequestration of mature parasites. we describe the characterization of the ves1 alpha gene encoding the vesa1a subunit, thus providing a description of a gene whose product is involved in rapid antigenic variation in a babesial parasite. this three-exon gene, a member of a multigene fami ... | 2000 | 10678177 |
| effect of breed of cattle on innate resistance to infection with anaplasma marginale transmitted by boophilus microplus. | to assess the innate resistance of and transmission in naive bos taurus cross bos indicus and purebred bos indicus cattle when placed in a paddock with cattle infected with anaplasma marginale and carrying boophilus microplus ticks. | 1999 | 10685172 |
| a serological survey of bovine babesiosis in northern and eastern zimbabwe. | the geographical distribution of babesia bovis and babesia bigemina antibodies in communal herds in northern and eastern zimbabwe was determined using the elisa technique. the animals in different herds in the study region had different levels of natural exposure to b. bovis (mean 32%, range 0-79%) and b. bigemina (mean 52%, range 5-92%) infections. the majority of herds (90%) were endemically unstable for b. bigemina and 62% were unstable for b. bovis. natural region 5 and manicaland province h ... | 1999 | 10689698 |
| phosphatidylcholine formation is the predominant lipid biosynthetic event in the hemoparasite babesia bovis. | this work examines the lipid composition and metabolism of bovine red blood cells infected by apicomplexan babesia parasites, organisms closely related to plasmodium sp. we found that erythrocytes infected with babesia bovis (i-rbc) accumulate lipids and show striking increases in phosphatidylcholine, phosphatidic acid, diacylglycerol and cholesteryl esters as compared to uninfected erythrocytes cultured under the same conditions (n-rbc). a similar pattern was observed in cultures of erythrocyte ... | 2000 | 10743618 |
| production and characterization of a panel of monoclonal antibodies for the identification of antigens of babesia bovis. | a panel of monoclonal antibodies was produced and characterized by an indirect fluorescent antibody test (ifat), an enzyme-linked immunosorbent assay (elisa) and western blotting with the aim of identifying antigens of babesia bovis. after fusion, the resultant hybrids were selected by the ifat, cloned, maintained in culture in vitro, and cryopreserved in liquid nitrogen. ten clones producing monoclonal antibodies were found to react against the entire merozoites, three reacted on the surface of ... | 2000 | 10763381 |
| more on babesia, no and malaria. | 2000 | 10827437 | |
| application of pcr assays to determine the genotype of babesia bovis parasites isolated from cattle with clinical babesiosis soon after vaccination against tick fever. | to demonstrate the value of pcr assays to determine the genotypes of babesia bovis in cattle with clinical signs of babesiosis within 3 weeks after vaccination against tick fever. | 2000 | 10860157 |
| cloned lines of babesia bovis differ in their ability to induce cerebral babesiosis in cattle. | clones of a babesia bovis isolate known to cause particularly severe cerebral babesiosis were tested for virulence phenotype by inoculation of cattle. clones were selected for phenotyping by two criteria - rate of growth in culture and hybridization of a virulence-related probe to southern blots. largely on the basis of associated mortality, b. bovis clones were judged to vary in their pathogenic potential. | 2000 | 10894468 |
| phylogenetic analysis with newly characterized babesia bovis hsp70 and hsp90 provides strong support for paraphyly within the piroplasms. | 2000 | 10924758 | |
| use of a duplex pcr/dna probe assay to monitor babesia bovis and babesia bigemina in cattle during a vaccination trial. | a duplex polymerase chain reaction (dpcr)/dna probe assay was used to detect babesia bovis and b. bigemina dna in cattle undergoing immunization trials. blood samples were collected from 15 non-splenectomized, 1-2 years old bulls, inoculated with 1 x 10(7) each of culture-derived b. bovis- and b. bigemina-infected erythrocytes. 15 bulls inoculated with normal erythrocytes served as a control group. all cattle were field exposed to tick-transmitted babesia 21 days (20 animals, group i) and 60 day ... | 1998 | 10932733 |
| babesia bovis-stimulated macrophages express interleukin-1beta, interleukin-12, tumor necrosis factor alpha, and nitric oxide and inhibit parasite replication in vitro. | the tick-transmitted hemoparasite babesia bovis causes an acute infection that results in persistence and immunity against challenge infection in cattle that control the initial parasitemia. resolution of acute infection with this protozoal pathogen is believed to be dependent on products of activated macrophages (mphi), including inflammatory cytokines and nitric oxide (no) and its derivatives. b. bovis stimulates inducible nitric oxide synthase (inos) and production of no in bovine mphi, and c ... | 2000 | 10948137 |
| babesia bovis and b. bigemina dna detected in cattle and ticks from zimbabwe by polymerase chain reaction. | from blood collected from 94 cattle at 12 locations in the eastern and northeastern areas of zimbabwe, dna was extracted and analysed by polymerase chain reaction with primers previously reported to be specific for babesia bigemina and babesia borvis. overall, dna of babesia bigemina was detected in the blood of 33/94 (35%) cattle and dna from b. bovis was detected in 27/58 (47%) of cattle. the prevalence of dna of b. bigemina was significantly higher in young animals (<2 years) (23/46) than in ... | 2000 | 10949512 |
| antigenic variation in vector-borne pathogens. | several pathogens of humans and domestic animals depend on hematophagous arthropods to transmit them from one vertebrate reservoir host to another and maintain them in an environment. these pathogens use antigenic variation to prolong their circulation in the blood and thus increase the likelihood of transmission. by convergent evolution, bacterial and protozoal vector-borne pathogens have acquired similar genetic mechanisms for successful antigenic variation. borrelia spp. and anaplasma margina ... | 2000 | 10998374 |
| the beta-tubulin gene of babesia and theileria parasites is an informative marker for species discrimination. | a fragment of the beta-tubulin gene was polymerase chain reaction (pcr) amplified from genomic dnas of babesia bovis, babesia bigemina, babesia divergens, babesia major, babesia caballi, babesia equi, babesia microti, theileria annulata and theileria sergenti. single amplification products were obtained for each of these species, but the size of the amplicons varied from 310 to 460 bp. sequence analysis revealed that this variation is due to the presence of a single intron, which ranged from 20 ... | 2000 | 11027785 |
| general review of tick species present in portugal. | at present, 24 species are known to occur in portugal: argas vespertilionis, ornithodoros maritimus and ornithodoros erraticus in argasidae; ixodes acuminatus, ixodes bivari, ixodes canisuga, ixodes frontalis, ixodes hexagonus, ixodes ricinus, ixodes simplex simplex, ixodes ventalloi, ixodes vespertilionis, dermacentor marginatus, dermacentor pictus', haemaphysalis hispanica, haemaphysalis inermis, haemaphysalis punctata, rhipicephalus bursa, rhipicephalus pusillus, rhipicephalus sanguineus, rhi ... | 1999 | 11071535 |
| cattle and small ruminant piroplasmosis in macedonia, greece. | macedonia is an endemic region of cattle as well as of sheep and goat piroplasmosis in cattle, theileria orientalis (=t. buffeli?), the agent of eurasian benign theileriosis, is the most common and widespread piroplasm species. t. annulata, the agent of tropical theileriosis, seems to be rare and limited to few foci, but causes very severe clinical cases, especially in imported pure-bred or cross-bred animals. babesia bovis and b. bigemina are present in several localities, and often coexist. ca ... | 1999 | 11071550 |
| tick-borne diseases in ruminants of central and southern italy: epidemiology and case reports. | sera and blood from cattle and sheep were examined for the presence of babesia and theileria spp by microscopy and serology at the parasitology department of the istituto zooprofilattico sperimentale of abruzzo and molise (izsam). of the 47 bovine herds (323 animals) tested, 15 were found positive for babesia bigemina and 1 for babesia bovis. two outbreaks occurred, one caused by b. bigemina and one by b. bovis. the b. bigemina outbreak occurred in abruzzo and has been followed for two years. th ... | 1999 | 11071553 |
| characterization of allelic variation in the babesia bovis merozoite surface antigen 1 (msa-1) locus and identification of a cross-reactive inhibition-sensitive msa-1 epitope. | the babesia bovis merozoite surface antigen 1 (msa-1), a member of the variable merozoite surface antigen (vmsa) family, is an immunodominant glycoprotein which elicits antibodies that inhibit erythrocyte invasion. while antigenic polymorphism is a general feature of vmsa genes, the molecular basis and extent of msa-1 sequence polymorphism have not been well characterized. in this study we defined the msa-1 locus in the biologically cloned mexico mo7 strain of b. bovis and identified the sequenc ... | 2000 | 11083806 |
| bovine borreliosis in botswana. | clinical borrelia theileri infection was reported for the first time in cattle from botswana concurrent with babesia bovis and theileria mutans infections. two animals, an ox and a cow of the tswana breed demonstrated clinical signs of fever, haemoglobinuria, inappetance, diarrhoea, pallor of mucous membranes, enlarged superficial lymph nodes and rough hair coats. examination of the blood smears from the affected animals revealed numerous b. theileri, and very few b. bovis and t. mutans organism ... | 2000 | 11131124 |
| elevated anti-parasitic activity in peripheral blood monocytes and neutrophils of cattle infected with babesia bovis. | the innate immune response to bovine babesia bovis infection in vivo has not previously been established. we used assays measuring phagocytosis and oxidative burst to investigate the immune response because they are indicative of the innate antimicrobial capacity of monocytes and neutrophils. monocyte and neutrophil phagocytosis is thought to be non-specific in nature and so the phagocytosis of either opsonised zymosan or escherichia coli was used to indicate the non-specific phagocytic capacity ... | 2001 | 11165268 |
| culture-derived parasites in vaccination of cattle against tick-borne diseases. | the major economically important tick-borne diseases of cattle are theileriosis, babesiosis, anaplasmosis, and cowdriosis. culture-derived attenuated schizonts of theileria annulata have proved to be safe for all types of cattle and they protect against tick-borne theileriosis. t. parva was also successfully grown in vitro; however, inoculation of cattle with allogeneic schizont-infected cells resulted in rejection and destruction of the parasites together with the host cells. the number of schi ... | 2000 | 11193616 |
| babesiosis (babesia bovis) stability in unstable environments. | enzootic stability (herd immunity) in bovine babesiosis occurs when the rate of transmission (inoculation rate) of babesia spp by the tick vector is sufficient to immunize a majority of susceptible calves before the loss of calfhood resistance. the effect of three tick (boophilus microplus) control strategies (none, threshold, and strategic) on enzootic stability and the likelihood of babesiosis (babesia bovis) outbreaks was studied using a spreadsheet age-class computer simulation model. the mo ... | 2000 | 11193666 |
| integrated molecular diagnosis of theileria and babesia species of cattle in italy. | a reverse line blot hybridization (rlb) test was developed to specifically identify six theileria spp. (t. annulata, t. parva, t. mutans, t. velifera, t. taurotragi, and t. buffeli/orientalis) and three babesia spp. (b. bovis, b. bigemina, and b. divergens). no cross reaction was observed with other livestock pathogens (such as anaplasma marginale, a. centrale, a. ovis, cowdria ruminantium, trypanosoma brucei, t. congolense, and t. vivax). this method was used to test bovine blood samples collec ... | 2000 | 11193668 |
| vaccination against bovine babesiosis. | bovine babesiosis is an important disease caused by babesia bovis, b. bigemina, and b. divergens. solid immunity develops after infection and this feature has been exploited with the use of live attenuated organisms as immunogens. attributes of live vaccines include a durable immunity to heterologous challenge after one vaccination. to overcome disadvantages relating to poor quality control (risk of contamination and adverse reactions), production procedures have been modified to meet the requir ... | 2000 | 11193669 |
| attenuated trivalent vaccine against babesiosis and anaplasmosis in colombia. | 2000 | 11193685 | |
| dna from protozoan parasites babesia bovis, trypanosoma cruzi, and t. brucei is mitogenic for b lymphocytes and stimulates macrophage expression of interleukin-12, tumor necrosis factor alpha, and nitric oxide. | the activation of innate immune responses by genomic dna from bacteria and several nonvertebrate organisms represents a novel mechanism of pathogen recognition. we recently demonstrated the cpg-dependent mitogenic activity of dna from the protozoan parasite babesia bovis for bovine b lymphocytes (w. c. brown, d. m. estes, s. e. chantler, k. a. kegerreis, and c. e. suarez, infect. immun. 66:5423-5432, 1998). however, activation of macrophages by dna from protozoan parasites has not been demonstra ... | 2001 | 11254571 |
| myosin diversity in apicomplexa. | a polymerase chain reaction (pcr) screen was used to examine the diversity of myosins in 7 apicomplexan parasites: toxoplasma gondii, plasmodium falciparum, neospora caninum, eimeria tenella, sarcocystis muris, babesia bovis, and cryptosporidium parvum. using degenerate pcr primers compatible with the majority of known myosin classes, putative myosin sequences were obtained from all of these species. all of the sequences obtained showed greatest similarity to previously identified apicomplexan m ... | 2001 | 11318578 |
| antigenic variation in babesiosis: is there more than one 'why'? | many intraerythrocytic hemoparasites survive the host immune system through rapid antigenic variation. among babesial parasites antigenic variation has been demonstrated convincingly only for babesia bovis and babesia rodhaini. the molecular basis for antigenic variation in babesial parasites and its possible connection with cytoadherence and sequestration are discussed. | 2001 | 11377210 |
| bovine piroplasms in minorca (balearic islands, spain): a comparison of pcr-based and light microscopy detection. | the present study provides the first epidemiological data regarding infection by theileria and babesia piroplasms in cattle in minorca. more than 94% of the studied animals were positive for the presence of theileria sp., and of those, 41.3% were positive for the presence of theileria annulata. these results indicate that the prevalence of mediterranean theileriosis caused by t. annulata is very high in minorcan dairy farms and that other theileria sp. are also present in the area. the prevalenc ... | 2001 | 11502372 |
| detection of haemoparasites in cattle by reverse line blot hybridisation with a note on the distribution of ticks in sicily. | a reverse line blot hybridisation (rlb) of 21 oligonucleotides with polymerase chain reaction (pcr) amplified regions of 16s rrna (ehrlichia/anaplasma group) or 18s rrna (babesia/theileria group) genes of haemoparasites detected theileria annulata, t. buffeli/orientalis, babesia bovis, b. bigemina, b. divergens, ehrlichia bovis, anaplasma marginale, a. centrale and unknown species within the rickettsia tribe.a very high prevalence of mixed infections was detected, which indicated that animals in ... | 2001 | 11511414 |
| detection of babesia equi (laveran, 1901) by nested polymerase chain reaction. | we describe a nested polymerase chain reaction (pcr) for the detection of babesia equi in equine infected erythrocytes using oligonucleotides designed on the published sequence of a b. equi merozoite antigen gene (ema-1). a 102bp dna fragment is specifically amplified from b. equi but not from babesia caballi, babesia bovis or babesia bigemina dna. in a mock infection we were able to detect down to six infected cells in 10(8) equine erythrocytes or to detect the parasite in blood with an equival ... | 2001 | 11587829 |
| the age-related immunity in cattle to babesia bovis infection involves the rapid induction of interleukin-12, interferon-gamma and inducible nitric oxide synthase mrna expression in the spleen. | young calves possess a strong innate immunity against babesia bovis infection that lasts for approximately 6 months after birth and is abrogated with the removal of the spleen. this immunity is characterized as cellular involving a soluble mediator. nitric oxide has been implicated by virtue of its babesiacidal affects in vitro, but questioned to be as effective in vivo, due to its ability to downregulate type-1 immunity. spleen cells were obtained from 4-month-old calves and adult steers and pr ... | 2001 | 11589775 |
| addition of hypoxanthine to culture media allows in vitro cultivation of babesia bovis and b. bigemina at reduced serum concentrations. | the microaerophilous stationary phase system (masp) was introduced in 1980 and successfully used as a standard technique for babesia bovis and b. bigemina in vitro culture. the percentage of serum in the medium and the dependence on specific serum donors have been recognized as important constraints both for immunochemical studies and for the logistics of culture routine. in the present study the supplementation of rpmi 1640 with hypoxanthine at a concentration between 50 and 200 microm has enab ... | 2001 | 11676367 |
| a novel 20-kilodalton protein conserved in babesia bovis and b. bigemina stimulates memory cd4(+) t lymphocyte responses in b. bovis-immune cattle. | acquired immunity against the hemoprotozoan parasite babesia bovis is believed to depend on activation of antigen-specific cd4(+) t lymphocytes and ifn-gamma production. a strategy was employed to identify potentially protective antigens from b. bovis based on memory cd4(+) t lymphocyte recognition of fractionated merozoite proteins. fractions of merozoites separated by continuous flow electrophoresis (cfe) that contained proteins of approximately 20 kda were shown previously to stimulate memory ... | 2001 | 11704278 |
| molecular approaches to elucidating innate and acquired immune responses to babesia bovis, a protozoan parasite that causes persistent infection. | for many vector-transmitted protozoal parasites, immunological control of acute infection leads to a state of persistent infection during which parasitemias may cycle unnoticed in infected but otherwise clinically healthy animals. achieving persistent infection is a strategy that favors parasitism, since both host and, therefore, parasite survive, and endemically infected animal populations provide a reservoir of parasites continually available for subsequent transmission. examples of the major ... | 2001 | 11707299 |
| molecular technology and antigenic variation among intraerythrocytic hemoparasites: do we see reality? | antigenic variation is one mechanism of immune evasion utilized by many microorganisms--encompassing such broad evolutionary groups as viruses, bacteria, and protozoa--to survive the onslaught of a specifically activated host immune system. because of its importance to the survival of many infectious agents there is considerable interest in understanding this phenomenon. with knowledge of the molecular mechanisms by which these microbes deliberately manipulate their genomes, it may be possible t ... | 2001 | 11707301 |
| il-4 and il-10 inhibition of ifn-gamma- and tnf-alpha-dependent nitric oxide production from bovine mononuclear phagocytes exposed to babesia bovis merozoites. | the requirement for ifn-gamma and/or tnf-alpha as co-stimulants with babesia bovis merozoites for nitric oxide (no) production was examined, as well as the regulatory role of il-4 and il-10. purified b. bovis merozoites did not induce the production of no in undifferentiated monocytes without addition of exogenous ifn-gamma and tnf-alpha unless the monocytes taken ex vivo were producing tnf-alpha endogenously. under the latter condition, the no production resulting from merozoite stimulation rem ... | 2002 | 11777537 |
| first report of babesia bovis in spain. | 2001 | 11787787 | |
| immunity following use of australian tick fever vaccine: a review of the evidence. | to review the evidence available on the degree and duration of immunity provided by australian tick fever vaccines against babesia bovis, b. bigemina and anaplasma marginale infections in australia and overseas. | 2001 | 11837905 |
| babesia bovis: culture of laboratory-adapted parasite lines and clinical isolates in a chemically defined medium. | babesiosis caused by babesia spp. is a disease of both veterinary and human importance. here, we describe a method to continuously culture laboratory lines and field isolates of babesia bovis in vitro in a chemically defined medium using (albu)max ii as an alternative to bovine serum. further, we have successfully cultured parasite isolates directly from cattle that failed to grow in traditional serum-containing medium. variation of atmospheric gas composition and culture volumes to determine op ... | 2001 | 11846527 |
| babesia bovis merozoite surface antigen 1 and rhoptry-associated protein 1 are expressed in sporozoites, and specific antibodies inhibit sporozoite attachment to erythrocytes. | we examined babesia bovis sporozoites for the expression of two molecules, merozoite surface antigen 1 (msa-1) and rhoptry-associated protein 1 (rap-1), that are postulated to be involved in the invasion of host erythrocytes. both msa-1 and rap-1 were transcribed and expressed in infectious sporozoites. importantly, monospecific msa-1 and rap-1 antisera each inhibited sporozoite invasion of erythrocytes in vitro. this is the first identification of antigens expressed in babesia sp. sporozoites a ... | 2002 | 11854249 |
| immunodominant epitopes in babesia bovis rhoptry-associated protein 1 that elicit memory cd4(+)-t-lymphocyte responses in b. bovis-immune individuals are located in the amino-terminal domain. | babesia bovis rhoptry-associated protein 1 (rap-1), which confers partial protection against b. bovis challenge, is recognized by antibodies and t lymphocytes from cattle that have recovered from infection and are immune to subsequent challenge. rap-1 is a 60-kda protein with an n-terminal (nt) region that contains four cysteine residues conserved among all babesia rap-1 family members and a c-terminal (ct) region that contains multiple, degenerate, tandem 23-amino-acid (aa) repeats. to define t ... | 2002 | 11895969 |
| identification of newly isolated babesia parasites from cattle in korea by using the bo-rbc-scid mice. | attempts were made to isolate and identify korean bovine babesia parasite. blood samples were collected from holstein cows in korea, and babesia parasites were propagated in scid mice with circulating bovine red blood cells for isolation. the isolate was then antigenically and genotypically compared with several japanese isolates. the korean parasite was found to be nearly identical to the oshima strain isolated from japanese cattle, which was recently designated as babesia ovata oshimensis n. v ... | 2002 | 11949211 |
| molecular phylogenetic study of theileria sp. (thung song) based on the thymidylate synthetase gene. | theileria type thung song is an indigenous hemoparasite of dairy cattle from the south of thailand. it has previously been classified using the analysis of a comparative set of small subunit ribosomal rna nucleotide sequences. however, the classification of this parasite is still questionable since the theileria type thung song was located as the intermediate parasite between pathogenic and benign groups. we use the thymidylate synthetase gene (ts) as an alternative for the rapid molecular phylo ... | 2002 | 12051604 |
| in vitro cultivation of chinese strains of babesia spp. | microaerophilus stationary phase culture techniques were applied for the continuous cultivation of two chinese strains of babesia bovis and b. bigemina, to determine the efficacy of antibabesial drugs. the efficacy of chloroquine phosphate was 25 times higher than that of berenil. primaquine phosphate only partially reduced the parasitaemia. the results show that chinese babesia strains can be cultivated in vitro and that this culture system is useful for the screening of antibabesial drugs. | 2002 | 12051608 |
| threat of foreign arthropod-borne pathogens to livestock in the united states. | there are many exotic animal pathogens throughout the world that, if introduced into the united states. could have a significant detrimental impact on the health of livestock, agricultural economy, the environment, and public health. many of these pathogens are arthropod-borne and potential vectors are readily available in the united states. a number of these arthropod-borne pathogens are discussed here as examples that illustrate the potential risk and the consequences of inadvertent introducti ... | 2002 | 12061432 |
| the babesia bovis merozoite surface antigen 2 locus contains four tandemly arranged and expressed genes encoding immunologically distinct proteins. | members of the variable merozoite surface antigen (vmsa) gene family of babesia bovis encode membrane proteins involved in erythrocyte invasion. in this study, we have identified and sequenced the complete 8.3-kb genomic locus containing msa-2, a member of the vmsa family, in the biologically cloned mexico mo7 strain. four tandemly arranged copies of msa-2-related genes were found in the locus. the four genes, designated msa-2a(1) (which corresponds to the originally described msa-2 gene), msa-2 ... | 2002 | 12065497 |
| myosins of babesia bovis: molecular characterisation, erythrocyte invasion, and phylogeny. | using degenerate primers, three putative myosin sequences were amplified from australian isolates of babesa bovis and confirmed as myosins (termed bbmyo-a, bbmyo-b, and bbmyo-c) from in vitro cultures of the w strain of b. bovis. comprehensive analysis of 15 apicomplexan myosins suggests that members of class xiv be defined as those with greater than 35% myosin head sequence identity and that these be further subclassed into groups bearing above 50-60% identity. bbmyo-a protein bears a strong si ... | 2002 | 12112135 |
| pcr-elisa for diagnosis of trypanosoma evansi in animals and vector. | a highly sensitive and specific polymerase chain reaction (pcr) based assay for the detection of trypanosoma evansi present in the blood of different animals and vector was developed. a simple lysis method was used to remove of the red blood cells to facilitate direct input of samples into the pcr reactions. the primer set was designed and synthesized to amplify a single band of 257 bp pcr product that was subsequently examined by enzyme-linked immunosorbent assay (elisa). the sensitivity limit ... | 2002 | 12144767 |
| epidemiology of bovine tick-borne diseases in southern italy. | this investigation was carried out in an area covering part of three southern italian regions: campania, basilicata and apulia. eighty-one farms were involved using the formula suggested by thrusfield; they were equally distributed over the area which was subdivided into 81 geo-referenced sub-areas. in may and june 1999 from a total of 506 cattle, older than 18 months, blood-samples were taken and ticks were collected and identified. serum samples were tested for antibodies of bahesia bigemina, ... | 2002 | 12199369 |
| cellular localization of babesia bovis merozoite rhoptry-associated protein 1 and its erythrocyte-binding activity. | the cellular localization of babesia bovis rhoptry-associated protein 1 (rap-1) and its erythrocyte-binding affinity were examined with anti-rap-1 antibodies. in an indirect immunofluorescent antibody test, rap-1 was detectable in all developmental stages of merozoites and in extracellular merozoites. in the early stage of merozoite development, rap-1 appears as a dense accumulation, which later thins out and blankets the host cell cytoplasm, but retains a denser mass around newly formed parasit ... | 2002 | 12228313 |
| evaluation of an enzyme-linked immunosorbent assay with recombinant rhoptry-associated protein 1 antigen against babesia bovis for the detection of specific antibodies in cattle. | the gene encoding babesia bovis rhoptry-associated protein 1 (rap-1) was used to develop an enzyme-linked immunosorbent assay (elisa) to measure specific antibodies against b. bovis. the b. bovis rap-1 gene was subcloned into a baculovirus transfer vector, and the rap-1 protein was expressed in insect cells infected with a recombinant baculovirus. the recombinant b. bovis rap-1 of 65 kda was detected with anti-rap-1 mouse serum by western blotting, and this recombinant rap-1 was used as an antig ... | 2002 | 12354879 |
| babesia bovis and b. bigemina: persistence of infection in friesian cows following vaccination with live antibabesial vaccines. | the persistence of babesia bovis and b. bigemina infection in friesian cows, following vaccination with attenuated live vaccines, was assessed by subinoculation of blood into splenectomized calves. subinoculation tests showed that b. bigemina persisted in two out of 20 cows vaccinated 10 and 46 months previously, and that b. bovis persisted in 11 out of 22 cows vaccinated 10 to 47 months previously. antibody was detected in five b. bigemina - and 15b. bovis -vaccinated cows. parasites of both sp ... | 2002 | 12359486 |
| babesia bovis merozoite surface antigen 2 proteins are expressed on the merozoite and sporozoite surface, and specific antibodies inhibit attachment and invasion of erythrocytes. | the babesia bovis merozoite surface antigen 2 (msa-2) locus encodes four proteins, msa-2a(1), -2a(2), -2b, and -2c. with the use of specific antibodies, each msa-2 protein was shown to be expressed on the surface of live extracellular merozoites and coexpression on single merozoites was confirmed. individual antisera against msa-2a, msa-2b, and msa-2c significantly inhibited merozoite invasion of bovine erythrocytes. as tick-derived sporozoites also directly invade erythrocytes, expression of ea ... | 2002 | 12379726 |
| age-related innate immune response in calves to babesia bovis involves il-12 induction and il-10 modulation. | there is a strong innate immunity in calves to infection with babesia bovis. interleukin (il)-12 and il-10 have been shown in vitro to be important immunoregulatory cytokines. here we demonstrate in vivo that the protective innate response in young calves to infection with virulent b. bovis involves the early appearance of il-12 and interferon-gamma (ifn-gamma) transcripts in the spleen. in contrast, il-12 and ifn-gamma mrna expression in the spleens of adult cattle that succumbed to the infecti ... | 2002 | 12381584 |
| residual effect of antibabesial drugs on the live redwater blood vaccines. | it has been demonstrated that the attenuated organisms used in the unfrozen south african babesia bovis and b. bigemina (redwater) vaccines are susceptible for longer periods to the residual effect of the anti-babesial drugs diminazene and imidocarb dipropionate than the virulent field strains. reports of vaccine failures in some animals vaccinated with the frozen south african redwater vaccines after prophylactic treatment with imidocarb dipropionate have led us to reinvestigate the validity of ... | 2002 | 12381585 |
| tick-borne parasitic diseases in cattle: current knowledge and prospective risk analysis related to the ongoing evolution in french cattle farming systems. | parasitic diseases, like babesiosis and theileriosis are transmitted by ticks: their occurrence is therefore linked to the size of the tick stock and the seasonality of the vectors. babesia divergens bovine babesiosis transmitted by ixodes ricinus is widespread and often reported in france. serological prevalence is high, ranging from 20 to 80% according to the farms. clinical incidence is low: around 0.4% for the whole cattle population. the endemic situation is unstable and clinical cases occu ... | 2002 | 12387492 |
| theobald smith--the discoverer of ticks as vectors of disease. | the cause of texas fever in cattle, which is characterised by lysis of erythrocytes leading to anaemia, icterus, haemoglobinuria, and death, remained unsolved for many decades and assorted theories were proposed as an explanation for a disease being transmitted by apparently healthy animals. from 1889 to 1893, theobald smith and frederick l. kilbourne could demonstrate in elegantly conducted experiments how the disease was spread from cattle to cattle by ticks serving as the vector of transmissi ... | 2002 | 12422586 |
| competitive enzyme-linked immunosorbent assay based on a rhoptry-associated protein 1 epitope specifically identifies babesia bovis-infected cattle. | the competitive enzyme-linked immunosorbent assay (celisa) format has proven to be an accurate, reliable, easily standardized, and high-throughput method for detecting hemoparasite infections. in the present study, a species-specific, broadly conserved, and tandemly repeated b-cell epitope within the c terminus of the rhoptry-associated protein 1 of the hemoparasite babesia bovis was cloned and expressed as a histidine-tagged thioredoxin fusion peptide and used as antigen in a celisa. the assay ... | 2003 | 12522037 |
| babesia bovis merozoite surface protein-2c (msa-2c) contains highly immunogenic, conserved b-cell epitopes that elicit neutralization-sensitive antibodies in cattle. | the search for vaccine candidates against bovine babesiosis caused by babesia bovis is greatly focused on the identification of merozoite surface-exposed antigens that are widely conserved, functionally relevant and immunodominant in cattle protected against b. bovis infections. we have recently identified msa-2c, a member of the b. bovis variable merozoite surface antigen (vmsa) gene family, which in contrast to other members, appears to be highly conserved among geographically distant b. bovis ... | 2003 | 12672522 |
| intra-uterine infection with babesia bovis in a 2-day-old calf. | infection with babesia bovis was diagnosed in a 2-day-old female calf apparently transmitted in utero. the calf was born as the second calving to a cross-bred beef cow permanently on pasture. diagnosis was based upon identification of b. bovis in peripheral blood smears and clinical signs which included fever, jaundice, pale mucous membranes and convulsions. anaemia, leucocytosis, thrombocytopenia and lymphocytosis were noted at the febrile acute stage of the disease. the blood smears revealed e ... | 2003 | 12675895 |
| growth inhibitory effect of triclosan on equine and bovine babesia parasites. | we evaluated the growth inhibitory effect of triclosan, which has recently been reported to inhibit the growth of plasmodium species and toxoplasma gondii, on bovine and equine babesia parasites in in vitro cultures the growth of babesia bovis and b. bigemina was significantly inhibited in the presence of 100 microg/ml of triclosan, while b. caballi and b. equi were susceptible to as low as 50 microg/ml. babesia bigemina and b. caballi were completely cleared as early as on the first and second ... | 2003 | 12685641 |
| characterisation of erythrocyte invasion by babesia bovis merozoites efficiently released from their host cell after high-voltage pulsing. | apicomplexa are a phylum of obligate intracellular parasites critically dependent on invasion of a host cell. an in vitro assay for erythrocyte invasion by babesia bovis was established, employing free merozoites obtained after the application of high-voltage to the parasitised erythrocytes. the invasion proceeds efficiently in phosphate-buffered saline solution without the requirement for any serum or medium components. the kinetics of invasion can be measured over a time span of 5-60 min after ... | 2003 | 12737991 |