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characterization of attenuated theileria annulata vaccines from spain and the sudan.theileriosis caused by theileria annulata can be effectively prevented by vaccination with attenuated, cultured schizonts. although these attenuated vaccines have been applied for a long time, not much is known about the fate of the vaccine strain in the field. here, two experimental spanish vaccine strains originating in cádiz and cáceres, and one sudanese strain are studied to address the development of a carrier status and the infectivity for hyalomma ticks. moreover, the heterogeneity of the ...200011193667
a preliminary study on the attenuation of tunisian schizont-infected cell lines of theileria annulata.four theileria annulata cell lines were characterised at low passage levels using two polymorphic markers and then used to infect calves. their virulence seemed to be related to the number of genotypes present within the cell line. in all, 3 of the 4 cell lines were cultured up to passage 100 or 200 and inoculated into calves. their characterisation using the same markers indicated that the attenuation was related to a reduction in the parasite polymorphism down to a single genotype. the immunog ...19968875574
successful long-term in vitro cultivation of theileria annulata schizonts in media supplemented with homologous and heterologous sera.the efficacy of medium rpmi-1640 supplemented with either foetal bovine, normal bovine, goat or sheep sera was compared for prolonged in vitro propagation of theileria annulata (hisar) schizonts. medium rpmi-1640 supplemented with 20% foetal bovine serum (standard growth medium) resulted in optimum growth of t. annulata (hisar) schizonts in vitro. comparable viability and non-viability counts were observed in growth media supplemented with normal bovine or goat sera. however, viability counts in ...19989806493
tissue damage in cattle infected with theileria annulata accompanied by metastasis of cytokine-producing, schizont-infected mononuclear phagocytes.the distribution of schizont-infected cells in six calves undergoing acute, lethal sporozoite-induced infections with theileria annulata was examined, the calves being killed in the early, middle or late stages of disease. a combination of histological and immunocytochemical techniques showed that schizont-infected cells became disseminated rapidly through the lymphoid tissues from the prescapular lymph node draining the site of inoculation to distant lymph nodes (e.g., precrural, mesenteric and ...199910098015
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 ...199910325324
loss of matrix metalloproteinase 9 activity in theileria annulata-attenuated cells is at the transcriptional level and is associated with differentially expressed ap-1 species.the schizont stage of the protozoan parasite theileria annulata reversibly transforms bovine monocytes into an immortalised and metastatic state. we have been studying t. annulata induction of host matrix metalloproteinases (mmp) which are involved in parasite dissemination and pathogenesis. we have observed that prolonged in vitro culture of t. annulata-infected cell lines results in their attenuation and this process is associated with alterations in both host and parasite gene expression. in ...200010743610
temporal co-ordination of macroschizont and merozoite gene expression during stage differentiation of theileria annulata.the bovine parasite, theileria annulata has a complex life-cycle involving the expression and repression of genes during development of its morphologically distinct life-cycle stages. in order to detail the molecular events that occur during differentiation of the intracellular multinucleate macroschizont to the extra-cellular uninucleate merozoite, we have isolated two genes, tash1 and tash2 which are differentially expressed during differentiation. nuclear run on data show that tash1 gene expr ...200111295177
[epidemiologic status of theileria annulata bovine theileriasis in tunisia]. 19948801842
transient transfection of theileria annulata.we have developed a method to transiently transfect infective, uninucleate, theileria annulata sporozoites. transfection vectors have been constructed using a number of t. annulata 5' gene flanking sequences linked to the enhanced green fluorescence protein (egfp) reporter gene. sporozoites were transfected with these constructs using the lipid transfection agent superfect, then allowed to infect purified bovine mononuclear cells (pbms). green fluorescence was observed in developing trophozoites ...200111356513
single dilution elisas using soluble piroplasm, cellular schizont and soluble schizont antigens for the detection of antibodies against theileria annulata.single dilution elisas were standardised for the determination of antibody titres against theileria annulata using three antigens namely soluble piroplasm, cellular schizont or soluble schizont antigens. antibody titres of 20 cattle serum samples of known identity were determined by multi-dilution elisa using the three antigens. the ratio of the optical density (od) of known positive and known negative sera at different serum dilutions were calculated and termed as positive/negative (p/n) ratios ...200111361152
identification of trypanosoma evansi by dna hybridisation using a non-radioactive probe generated by arbitrary primer pcr: short communication.a highly reproducible, dominant, monomorphic fragment of 473 base pair (bp) amplified from the genome of trypanosoma evansi by arbitrary primer-polymerase chain reaction (ap-pcr) was labelled with digoxigenin and investigated for its potential as dna probe. dot-blot hybridisation of total genomic dna with the probe proved useful in detecting bubaline, cameline and equine strains of t. evansi down to 10 pg of parasite template dna. no cross-hybridisation was seen with babesia bigemina, theileria ...200111402647
theileria annulata: identification, by differential mrna display, of modulated host and parasite gene expression in cell lines that are competent or attenuated for differentiation to the merozoite.to identify both host and parasite genes that show altered expression during differentiation of theileria annulata from the macroschizont to the merozoite stage of the life cycle, the rna profiles of two t. annulata-infected clonal cell lines (d7 and d7b12) with the same genetic background have been compared by rna display. in the cloned cell line d7, t. annulata differentiates from the macroschizont to the merozoite at 41 degrees c, whereas in the cell line d7b12, which was derived by recloning ...200111426947
molecular phylogenetic studies on theileria parasites based on small subunit ribosomal rna gene sequences.classification of theileria parasites of south-east asian countries is still ambiguous due to the lack of basic studies, especially their molecular genetic information. in this study, we included 6 known species and 14 unclassified theileria parasite isolates: theileria annulata, theileria parva, theileria taurotragi, theileria sergenti, theileria buffeli, theileria types sable, theileria types a, b, b1, b2, c, d, e, f, g, g1, theileria type medan (indonesia), theileria type ipoh (malaysia) and ...199910392966
[phenotypic and molecular analysis of isolates of theileria annulata]. 19948801843
proinflammatory cytokine expression by theileria annulata infected cell lines correlates with the pathology they cause in vivo.control of theileria annulata is currently best achieved by the use of live attenuated cell line vaccines. however, the mechanisms underlying attenuation are unclear and there is a need to rapidly produce new cell line vaccines, which could safely and effectively vaccinate cattle against tropical theileriosis. there is increasing evidence to suggest that proinflammatory cytokines produced by t. annulata infected cells play a central role in both pathology and immune evasion. this study aimed to ...200111282205
the akt/pkb pathway is constitutively activated in theileria-transformed leucocytes, but does not directly control constitutive nf-kappab activation.the intracellular protozoan parasites theileria parva and theileria annulata transform leucocytes by interfering with host cell signal transduction pathways. they differ from tumour cells, however, in that the transformation process can be entirely reversed by elimination of the parasite from the host cell cytoplasm using a specific parasiticidal drug. we investigated the state of activation of akt/pkb, a downstream target of pi3-k-generated phosphoinositides, in theileria-transformed leucocytes ...200111488815
effect of vaccination in the field with the theileria annulata (hisar) cell culture vaccine on young calves born during the winter season.the responses were monitored of young crossbred calves vaccinated against tropical theileriosis during the winter against a field tick challenge in the disease season. thirty-eight calves below 2 months of age, born after the end of the disease season, were selected at an organized farm. twenty-five animals were vaccinated with theileria annulata (hisar) cell culture vaccine (developed at ccs hau hisar laboratory) after the end of the disease season and 13 calves were kept as non-vaccinated cont ...200111334147
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 ...200111511414
theileria annulata: attenuation of a schizont-infected cell line by prolonged in vitro culture is not caused by the preferential growth of particular host cell types.flow cytometry and monoclonal antibodies to bovine leucocyte surface antigens were used to identify the types of host cells that the sporozoites of theileria annulata infect in cattle, to determine whether virulent schizont-infected cell lines (lines) differed phenotypically from avirulent lines, and to establish whether attenuation in vitro was accompanied by the preferential growth of particular host cell types. the surface antigens of four pairs of t. annulata (ta) (hisar) lines derived ex vi ...200111560412
a general review on the prevention and treatment of theileria annulata in china.a review is given of the prevention and treatment of theileria annulata infection of cattle in china. primaquine phosphate has been shown to be an effective drug for the elimination of gametocytes of t. annulata and an attenuated strain of virulent parasites is used as a vaccine. this vaccine has proved to be 100% safe and over 90% effective. since the use of these two methods of control, the disease caused by t. annulata in cattle in china has been controlled.19979195712
impact of field vaccination with a theileria annulata schizont cell culture vaccine on the epidemiology of tropical theileriosis.tropical theileriosis, caused by theileria annulata, is an important tick-borne disease of cattle. a cell culture attenuated vaccine has been developed in our laboratory by long-term in vitro propagation of the schizont stage of the parasite. a longitudinal study was conducted at selected farms housing indigenous, cross-bred and exotic animals to investigate the effect of vaccination on the epidemiology of the disease. a total of 120 animals in 4 age groups were vaccinated with the vaccine befor ...200111587838
characterisation of a cluster of genes encoding theileria annulata at hook dna-binding proteins and evidence for localisation to the host cell nucleus.infection of bovine leukocytes by the apicomplexan parasite theileria annulata results in alteration of host cell gene expression and stimulation of host cell proliferation. at present, the parasite-derived factors involved in these processes are unknown. recently, we described the characterisation of a parasite gene (tashat2), whose polypeptide product bears at hook dna-binding motifs and may be transported from the parasite to the host nucleus. we now describe the isolation of a further two ge ...200111683409
the proliferation-associated nuclear protein ki-67 in the bovine system: partial characterisation and its application for determination of the proliferation of theileria-infected bovine cells.theileria annulata-infected bovine cells as well as mitogen-stimulated bovine peripheral blood mononuclear cells (pbmc) express a proliferation-associated nuclear protein equivalent to the human ki-67 protein. in analogy to the human system, the expression of the bovine ki-67 protein is restricted to proliferating cells only, since (a) ki-67 expression paralleled [3h]-thymidine incorporation in concanavalin a (con a)-stimulated bovine pbmc, (b) ki-67 was not detectable in quiescent bovine cells, ...199910431723
identification of a 40s ribosomal protein (s17) that is differentially expressed between the macroschizont and piroplasm stages of theileria annulata.the nucleotide and protein sequence of the 40s ribosomal protein s17 (ribs17) of the protozoan parasite theileria annulata has been determined. southern blot analysis showed the gene was single copy and comparative sequence analysis revealed that the predicted polypeptide had high sequence homology with the ribs17 from other organisms. northern blot analysis showed that there was a 3-fold increase in the level of ribs17 rna between the macroschizont and the piroplasm stage of the lifecycle, wher ...200211796124
validation of an in vitro method to determine infectivity of cryopreserved sporozoites in stabilates of theileria spp.the infectivity of 15 cryopreserved theileria spp. sporozoite stabilates was assessed semi-quantitatively by titration using naive peripheral blood mononuclear cells (pbm) in vitro in multi-well plates. using the method described, the effective dilution, which would result in 50% of replicate wells infected (ed50), was calculated. the ed50 for 11 theileria annulata stabilates in bovine pbm ranged from 10(-2.6) to 10(-4.2) dilutions of 1 tick equivalent (t.e.) ml(-1), one stabilate of theileria p ...200211812618
study of theileria annulata population structure during bovine infection and following transmission to ticks.tams1 is the polymorphic immunodominant merozoite-piroplasm surface protein of theileria annulata. evidence for selection of divergent forms of tams1 has been obtained recently. this study was performed to address whether selection takes place during persistent infection of the bovine host or during passage through the hyalomma tick vector. four calves were infected with a t. annulata isolate representing multiple parasite genotypes. the development of the parasite population was analysed by den ...200111814042
characterization of a polymorphic theileria annulata surface protein (tasp) closely related to pim of theileria parva: implications for use in diagnostic tests and subunit vaccines.theileria annulata is a tick-transmitted protozoan that causes tropical theileriosis, an often fatal leukoproliferative disorder of cattle. to characterize and identify parasite proteins suitable as diagnostic antigens and/or vaccine candidates, a cdna clone encoding a macroschizont stage protein was isolated and characterized (here designated tasp). the gene, present as a single copy within the parasite genome, is transcribed in the sporozoite and schizont stage and codes for a protein of about ...200211897130
field evaluation of pcr in detecting theileria annulata infection in cattle in eastern turkey. 200212019536
infection and transformation of dendritic cells from bovine afferent lymph by theileria annulata.following incubation with sporozoites of the protozoan parasite theileria annulata, dendritic cells (dc), extracted from bovine afferent lymph, became infected and transformed into large, rounded, continuously proliferating cell lines. phenotypic analysis of the transformed cells by immunostaining and flow cytometry revealed that they expressed mhc class i and ii antigens, the myeloid marker myd (sirp alpha) and the bovine wc6 (workshop cluster 6) molecule. transformed dc cell lines differed fro ...200212049411
haematological profiles in pure bred cattle naturally infected with theileria annulata in saudi arabia.the abbott cell dyn 3500 haematology analyzer was employed to study haematological parameters in 41 adult and young friesian cattle naturally infected with theileria annulata in the qassim region of saudi arabia. comparison was made with clinically healthy adult and young friesian cattle. changes in blood parameters in t. annulata-infected cattle indicated severe macrocytic hypochromic anaemia, panleukopenia, lymphocytopenia, eosinopenia, neutropenia and thrombocytopenia but no reticulocytosis.200212072222
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 ...200111502372
tacrk3 encodes a novel theileria annulata protein kinase with motifs characteristic of the family of eukaryotic cyclin dependent kinases: a comparative analysis of its expression with tacrk2 during the parasite life cycle.the tacrk3 gene from the bovine apicomplexan parasite theileria annulata, encodes a 46 kda polypeptide with strong homology to the eukaryotic family of cyclin-dependent kinases. tacrk3 does not show significant alignment with any particular cdk group, other than the pfmrk kinases from the related apicomplexans plasmodium falciparum and plasmodium yoelii. it has a putative bipartite nuclear localization signal and is located to parasite nuclei by ifat. protein levels are constitutive throughout d ...200111733137
direct and sensitive detection of trypanosoma evansi by polymerase chain reaction.the mechanically transmitted haemoflagellate, trypanosoma evansi causes 'surra', a wasting disease of domestic animals and is highly endemic in distribution in southeast asia. the detection of t. evansi is important for improving the epizootiological and animal health status of the region. the specificity and sensitivity of polymerase chain reaction (pcr) using oligonucleotide primers constructed from t. evansi repetitive dna sequences were studied in the present investigation. using the assay, ...199910497829
transformation of leukocytes by theileria parva and t. annulata.theileria parva and t. annulata provide intriguing models for the study of parasite-host interactions. both parasites possess the unique property of being able to transform the cells they infect; t. parva transforms t and b cells, whereas t. annulata affects b cells and monocytes/macrophages. parasitized cells do not require antigenic stimulation or exogenous growth factors and acquire the ability to proliferate continuously. in vivo, parasitized cells undergo clonal expansion and infiltrate bot ...199910547684
pan-mediterranean comparison for the molecular detection of theileria annulata.seven laboratories decided to compare their molecular diagnostic techniques to identify mediterranean theileriosis caused by theileria annulata. each laboratory used either pcr or pcr and reverse line blot hybridization (rlb) to identify t. annulata. five laboratories sent their own samples to laboratory 4 to be recoded and passed on to at least two other laboratories. a total of 120 blood samples were analyzed during this study, generating 540 results. laboratory 1 sent only t. annulata-infecte ...200212381566
reverse line blot hybridization used to identify hemoprotozoa in minorcan cattle.piroplasmosis, a tick-borne protozoal disease, is an important disease affecting domestic and wild animals. we performed pcr-based reverse line blot hybridization (rlb) assays on blood samples obtained from 133 cattle exposed to ticks in field conditions in minorca (balearic islands, spain) in three different seasons. the oligonucleotides used were those for theileria annulata, t. buffeli, t. taurotragi, t. velifera, babesia bigemina, b. bovis, b. divergens, and b. major. the rlb technique allow ...200212381567
the innate resistance of kenana cattle to tropical theileriosis (theileria annulata infection) in the sudan.a study was carried out to assess the innate resistance of the indigenous kenana breed of cattle in the sudan to tropical theileriosis, theileria annulata infection of cattle. nine susceptible kenana calves were obtained from an area free from tropical theileriosis and the vector tick hyalomma anatolicum anatolicum and were found negative to t. annulata antibodies in the indirect fluorescent antibody test. they were infected by inoculation of 1.0 ml t. annulata sporozoite stabilate. three friesi ...200212381583
prevalence of blood parasites among cattle at the central area of saudi arabia.the present study aimed to investigate the parasites infecting cattle blood at al-qassim region. examination of 307 blood samples revealed that 235 (76.5%) and 3 (0.98%) of cattle were infected with theileria annulata and anaplasma marginale, respectively. t. annulata was the prevalent blood parasite among cattle while a. marginale was scarcely encountered. the monthly incidence of t. annulata ranged from 38.5% in march to 94.7% in october. also, the infection rate reached a maximum (84.3%) in b ...200010622615
biochemical profiles in friesian cattle naturally infected with theileria annulata in saudi arabia.the biochemical parameters were studied in adult and young friesian cattle naturally infected with theileria annulatta in the qassim region, saudi arabia. forty-three clinical cases of tropical theileriosis were studied, together with 40 clinically healthy friesian cattle. cattle clinically infected with t. annulata had significantly lower serum total protein, albumin, globulin, creatinine, calcium, phosphorus, magnesium, potassium, iron and copper concentrations and significantly higher ast act ...200312625400
genetic and phenotypic analysis of tunisian theileria annulata clones.many parasite species are known to show high levels of genetic diversity, yet the consequences of this diversity for host-parasite interactions are not well understood. variation in phenotypic traits such as growth rates and the ability to form transmission stages are raw material for natural and artificial selection to act upon with consequences for the evolution of the parasite species and disease control. in order to study genetic and phenotypic diversity amongst theileria annulata parasites, ...200312666883
detection of theileria annulata in cattle and vector ticks by pcr using the tams1 gene sequences.a polymerase chain reaction (pcr) and southern blot hybridization for the detection of theileria annulata are described. the pcr used primers amplifying a 785 base-pair fragment of the t. annulata gene which encodes the 30 kda major merozoite surface antigen, tams1. the sensitivity of the pcr in bovine blood was 1 piroplasm in 1 microl of blood. t. buffeli, t. parva, babesia bigemina, b. bovis and b. divergens were not detected. the pcr detected down to 1 infected acinus/tick in resting and part ...200010759082
a rapid mtt colorimetric assay to assess the proliferative index of two indian strains of theileria annulata.a study was undertaken to compare the proliferative index of macroschizont-infected lymphoblastoid cells of two indian strains [izatnagar (izt) and parbhani (pbn)] of theileria annulata by an in vitro mtt [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide], colorimetric assay. culture conditions were standardized to define the optimal cell concentration in 96-well microculture plates to yield nearly 100% living cells for measurement of the metabolized formazan activity. a cell conce ...200312719135
comparative studies on surface phenotypes of theileria lestoquardi and t. annulata schizont-infected cells.phenotypes of sheep cell lines infected with theileria lestoquardi or t. annulata were studied by flow cytometric analysis, following immunolabelling with a panel of monoclonal antibodies reacting to leukocyte differentiation antigens. cell surface phenotypes of theileria-infected sheep cell lines derived ex vivo and in vitro were compared, both with each other and with cell lines from cattle undergoing acute t. annulata infection. besides the non-lineage specific markers cd45, mhc class i and m ...200111570564
a role for tertiary structure in the generation of antigenic diversity and molecular association of the tams1 polypeptide in theileria annulata.the major merozoite-piroplasm surface antigen (mmpsa) of theileria annulata, tams1, is known to be antigenically diverse. the possession of variable n-linked glycosylation sites and removal of monoclonal antibody 5e1 reactivity by mild periodate treatment suggested, previously, that divergent epitopes may be conferred by secondary modification. this study has shown that monoclonal antibody 5e1 and polyspecific antisera raised against the native protein react against divergent amino acid epitopes ...200212076770
theileria lestoquardi and t. annulata in cattle, sheep, and goats. in vitro and in vivo studies.theileria annulata, causing bovine tropical theileriosis, and t. lestoquardi (syn t. hirci), the agent of malignant ovine theileriosis, are both transmitted by ticks of the genus hyalomma. their distribution is thus very similar and, should these parasites infect more than one ruminant species, the difficulty in interpreting epidemiological studies is magnified considerably. a pilot series of experiments was thus conducted in which cattle, sheep and goats were infected with sporozoites of a sing ...19989668448
determination of duration of immunity of calves vaccinated with the theileria annulata schizont cell culture vaccine.bovine tropical theileriosis caused by theileria annulata is a serious haemoprotozoan disease of cattle affecting exotic cattle, their crossbreeds and young indigenous calves. cell culture vaccines have been developed and used effectively in various countries for the control of this disease. however, the duration of immunity provided by these vaccines is poorly understood. the present experiments were planned to study the duration of immunity in animals after vaccination with the t. annulata (hi ...200010828509
generation of theileria annulata-specific cytotoxic t lymphocytes coincides with the control of tropical theileriosis. 199910494818
characterization of efferent lymph cells and their function following immunization of cattle with an allogenic theileria annulata infected cell line.immunization of cattle with in vitro propagated bovine mononuclear cells infected with theileria annulata induces a protective immune response. activation and effector function of t cells exiting the lymph node draining the site of cell line immunization were investigated to understand the mechanisms involved in the generation of immunity. immunized animals exhibited a biphasic immune response in efferent lymph as well as peripheral blood. the first phase corresponded to allogenic responses agai ...200312753774
[clinical aspects and tratment of theileria annulata infection in cattle in syria]. 196514271804
initiation of translation and cellular localization of theileria annulata casein kinase iialpha: implication for its role in host cell transformation.theileria annulata and t. parva are protozoa that infect bovine leukocytes which leads to subsequent transformation and uncontrolled proliferation of these cells. it has been proposed that the ckiialpha subunit of t. parva induces mitogenic pathways of host leukocytes by being exported into the host cell. the evidence for this is the existence of a predicted n-terminal secretion signal-like peptide. we tested this hypothesis by analyzing gene structure, translation, and protein localization of t ...200312891701
a study about tick vectors of bovine theileriosis in an endemic region of iran.the aim of this study was to determine the population of ticks in infected cattle and to identify the tick vectors of bovine theileriosis in an endemic area of iran from 1998 to 1999. a total of 120 suspected cattle suffering from theileriosis were clinically examined and investigated for the presence of theileria annulata in blood smears and the presence of any tick species on the body of cattle. in this study, 680 ticks were collected from 107 cattle infected with t. annulata. the prevalence o ...200314629004
tashhn, a theileria annulata encoded protein transported to the host nucleus displays an association with attenuation of parasite differentiation.the intracellular apicomplexan parasite, theileria annulata, manipulates its bovine host cell by over-riding the cells natural apoptotic response and inducing proliferation of the infected leukocyte. we have recently identified a t. annulata encoded family of polypeptides (tashats) with characteristics that indicate that they are involved in control of host cell gene expression. here we present data on another member of this family, tashhn, showing that it is located to the parasite and host cel ...200314641179
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 ...200011027785
application of the recombinant theileria annulata surface protein in an indirect elisa for the diagnosis of tropical theileriosis.the recombinant surface protein of theileria annulata (tasp) was used in the standardization and validation of an enzyme linked immunosorbent assay (elisa) for the detection of circulating antibodies against tropical theileriosis. elisa data were expressed as the percentage positivity (pp) of the reactivity of an internal positive control. a total of 50 sera samples from a disease-free area were used for the calculation of the cut-off value which served as a threshold between the positive and th ...200414722760
distribution and ecology of ticks (acari: ixodidae) infesting livestock in tunisia: an overview of eighth years field collections.ticks (ixodidae) play a significant role as vectors of pathogens of domestic animals in tunisia. the major losses caused by ticks are related to transmission of protozoan parasites. these include agents of tropical theileriosis and babesiosis in ruminants. since 1991, we conducted research studies on tick population of livestock in tunisia. this overview reports a synthesis on tick distribution, their biology and their role as vectors of pathogens in domestic animals, particularly cattle. during ...199911071534
a first glimpse into the pattern and scale of gene transfer in apicomplexa.reports of plant-like and bacterial-like genes for a number of parasitic organisms, most notably those within the apicomplexa and kinetoplastida, have appeared in the literature over the last few years. among the apicomplexan organisms, following discovery of the apicomplexan plastid (apicoplast), the discovery of plant-like genes was less surprising although the extent of transfer and the relationship of transferred genes to the apicoplast remained unclear. we used new genome sequence data to b ...200415003488
molecular genetic characterization and subcellular localization of theileria annulata mitochondrial heat-shock protein 70.a theileria annulata mitochondrial heat-shock protein of the 70-kda family (tamthsp70) was isolated by screening of the cdna library of a t. annulata-infected bovine lymphoblastoid cell line with an antibody raised against t. annulata schizonts. the tamthsp70 coding sequence was found to be most closely related to a previously reported mitochondrial hsp70 gene of eimeria tenella exhibiting a similarity of 67% with mitochondrial hsp70 genes of eukaryotic plants (pisum sativum, phaseolus vulgaris) ...200010894469
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 ...199911071535
quantitative analysis of pro-inflammatory cytokine mrna expression in theileria annulata-infected cell lines derived from resistant and susceptible cattle.the pathogenic mechanisms involved in tropical theileriosis, caused by the tick-borne protozoan parasite theileria annulata, are unclear. pathology is associated with the schizont stage of the parasite, which resides within bovine macrophages. breed-specific differences in pathology have been observed in cattle, several bos indicus breeds are relatively resistant to tropical theileriosis whilst bos taurus cattle are highly susceptible. infected cells express pro-inflammatory cytokines and it has ...200415113657
a role for matrix metalloproteinases in the pathology and attenuation of theileria annulata infections.upon infection with theileria annulata, bovine leukocytes are induced to express eight novel metalloproteinase activities. in this article, rachel adamson and roger hall suggest that these enzymes are virulence factors and their presence may explain some of the features of the pathology of the disease. specifically, they discuss the possibility that the metastatic properties of infected cells, the 'cigarette burn' ulcers and the cachexia characteristic of tropical theileriosis are associated wit ...199715275152
discrimination between theileria lestoquardi and theileria annulata in their vectors and hosts by rflp based on the 18s rrna gene.theileria lestoquardi and t. annulata can occur in similar vectors, and current available probes based on the 18s rrna gene showed cross-reaction between the two species. however, we developed a species-specific rflp test based on the mspi restriction enzyme, able to cut amplified products from t. lestoquardi only and to discriminate the two species in both tick and blood samples.200415372232
[growth of theileria annulata and t. parva in tissue culture]. 195813592881
control of lymphoproliferation by theileria annulata.the economic importance of bovine theilerioses has prompted several new approaches to understanding the diseases in the hope of developing more efficient methods of control. most theileria species that infect cattle cause a lymphoproli ferative disease. sporozoites, injected into the host bloodstream by the tick vectors, rapidly invade host lymphocytes and stimulate rapid division of infected cells. as these rupture, merozoites are released which invade red blood cells ready to infect feeding ti ...198715462874
epidemiology of mediterranean theileriosis in extremadura region, spain.extremadura is an extensive region (41,000 km2) located in the southwest of spain, where animal husbandry is a very important economical resource. livestock parasitism of ticks is common in the region and it is favoured by the environmental conditions and management systems. mediterranean theileriosis (mt) is perhaps the most important tick-borne disease of cattle. although theileria annulata has been identified in extremadura since 1933, little epidemiological information is available. during t ...199911071543
antigens and immunity in theileria annulata.about 200 million cattle are believed to be at risk from the debilitating and often fatal effects of tropical theileriosis, caused by theileria annulata. currently, there is no very cheap effective drug for treatment of t. annulata infections, although the hydroxynophthoquinones parvaquone and buparvaquone are reported to give good results(1-4). control of the parasite principally involves vector control against the ixodid tick vectors - mainly by cattle dipping and spraying with acaricides - an ...198815463119
in vitro infectivity and in vivo cross-protectivity of theileria lestoquardi and t. annulata in sheep and cattle. 19989668499
identification of antigenic proteins of a theileria species pathogenic for small ruminants in china recognized by antisera of infected animals.the antigenic proteins of the piroplasm stage of theileria species (china), the causative agent of theilerosis of small ruminants in china, were analyzed by western blot, revealing several specific immunoreactive proteins of different predicted molecular weights. furthermore, sera from theileria species (china)-infected animals were probed for reactivity with the tasp protein of t. annulata, for which a homologue has been described in theileria species (china). affinity chromatography demonstrat ...200415604487
cytokine production/t-cell-stimulatory ability of theileria annulata-infected cells and post-vaccinal reactions. 19989668500
bos taurus and bos indicus (sahiwal) calves respond differently to infection with theileria annulata and produce markedly different levels of acute phase proteins.disease-resistant livestock could provide a potentially sustainable and environmentally sound method of controlling tick and tick-borne diseases of livestock in the developing world. advances in the knowledge and science of genomics open up opportunities to identify selectable genes controlling disease resistance but first, breeds and individuals with distinguishable phenotypes need to be identified. the bos indicus breed, sahiwal, has been exploited in dairy breeding programmes, because it is r ...200515722085
evidence for strain specificity in cytotoxic t-lymphocyte-mediated, major histocompatibility complex class i-dependent killing of theileria annulata-infected cells.cattle immunised against theileria annulata with one parasite strain have been found to be immune to re-challenge with different strains of the parasite. however, recent evidence of apparent strain specificity has been documented in cattle immunised with attenuated parasite-infected cells. in this study the strain specificity of major histocompatibility complex class i-restricted cytotoxic t-lymphocytes (ctl), a major anti-parasite effector mechanism, was examined. ctl generated following challe ...19989694379
chemotherapeutic screening of compounds against theileria annulata in tissue culture.theileria annulata has been grown in tissue culture and these cultures have been used for screening compounds for chemotherapeutic activity against this parasite. the method described is simple and convenient for testing many compounds in a short time. forty compounds, including antimalarials, trypanocides, and antibiotics, have been examined, but none has been found to be active.195813618551
hereditary transmission of theileria annulata infection in the tick, hyalomma aegyptium neum. 195015443043
genome of the host-cell transforming parasite theileria annulata compared with t. parva.theileria annulata and t. parva are closely related protozoan parasites that cause lymphoproliferative diseases of cattle. we sequenced the genome of t. annulata and compared it with that of t. parva to understand the mechanisms underlying transformation and tropism. despite high conservation of gene sequences and synteny, the analysis reveals unequally expanded gene families and species-specific genes. we also identify divergent families of putative secreted polypeptides that may reduce immune ...200515994557
comparison between two tests results, kappa statistic instead of simple overall agreement. 200516011877
validation of the indirect tasp enzyme-linked immunosorbent assay for diagnosis of theileria annulata infection in cattle.an elisa based on a recombinant theileria annulata surface protein (tasp) was evaluated for detection of antibodies in sera from cattle exposed to tropical theileriosis in sudan. the reference positive samples, used in this study, were from theileria-infected populations and consisted of 80 cattle from an endemic area in khartoum state, with high antibody titers in the indirect fluorescent antibody test (ifat). the reference negative samples were taken from non-exposed populations and consisted ...200516052361
cattle infestation by hyalomma ticks and prevalence of theileria in hyalomma species in the east of turkey.a total of 2388 cattle and 442 shelters, from two provinces (elazig and malatya) endemic for tropical theileriosis in the east of turkey, were studied for hyalomma tick populations from july 1993 to july 1995 in elazig and from may 1998 to january 1999 in malatya. four thousand five hundred and eighty one of 7455 hyalomma ticks were collected from cattle, the other ticks (2874) were collected from shelters. all of the ticks collected from shelters were hyalomma anatolicum anatolicum. two thousan ...200415036571
proliferation and cytokine profile of t. annulata-infected ovine, caprine, and bovine lymphoblastoid cells.t. annulata, the causative agent of tropical theileriosis in cattle, can also infect ovine and caprine leukocytes in vitro. in vivo studies showed that this parasite causes a mild infection in both these animal species, and in sheep merozoite stage development seems to be inhibited. since the nature of t. annulata infected caprine and ovine cells is not known, all three cell lines were karyotyped and phenotypically characterized by flow cytometry. they all express mrna of cytokines il-1 alpha, i ...200011193699
reduction of theileria annulata infection in ticks fed on calves immunized with purified larval antigens of hyalomma anatolicum anatolicum.larval antigen of hyalonmma anatolicum anatolicum, the vector of theileria annulata, was purified by two-step affinity chromatography using anti-tick gut-specific rabbit igg and igg from immunized cattle. the purified antigen showed the presence of a single polypeptide of 37 kda (ghlagp) on sds-page. two groups (i and ii) of naive crossbred calves (bos taurus x b. indicus) were immunized with i mg of ghlagp in three divided doses. immunized calves of group i were also infected with a sublethal d ...200516274006
development of a recombinant indirect elisa for the diagnosis of theileria sp. (china) infection in small ruminants.theileria sp. (china) causes severe limitations on the development of the livestock industry in the north-west of china. an enzyme-linked immunosorbent assay (elisa) based on merozoite homogenate of the parasite for diagnosis of infection has been established; however, cross-reactivity with other small ruminant-infecting piroplasms could not be excluded. thus, a prerequisite for epidemiological surveys and diagnosis was the establishment of a recombinant protein-based elisa. to this end, serum f ...200616425067
recent development in control of theileria annulata in iran.during 1973-1990 cattle immunization, in iran, was induced by two strains within an interval of one month: first the milder and then the mild strain. although this method of vaccination rendered satisfactory results in the field, yet production, maintenance in deep-freezers and transportation in liquid nitrogen particularly to remote areas of the country proved to be uneconomical and time consuming. therefore, in order to reduce cost and save time, a new method involving only one local and live ...19989754318
infection of calves with theileria annulata in tunisia: economic analysis and evaluation of the potential benefit of vaccination.a field study aiming to estimate the costs of tropical theileriosis was carried out in an endemic region of the north of tunisia. three farms were monitored for two successive summer seasons. a total number of 56 calves and 12 sentinel cows were monitored. calves were ranked into four groups: non infected animals, diseased animals with clinical tropical theileriosis, sub-clinical theileria annulata infected animals with anaemia and sub-clinical t. annulata infected animals without anaemia. the t ...200616481113
structural implications of novel diversity in eucaryal rnase p rna.previous eucaryotic rnase p rna secondary structural models have been based on limited diversity, representing only two of the approximately 30 phylogenetic kingdoms of the domain eucarya. to elucidate a more generally applicable structure, we used biochemical, bioinformatic, and molecular approaches to obtain rnase p rna sequences from diverse organisms including representatives of six additional kingdoms of eucaryotes. novel sequences were from acanthamoeba (acathamoeba castellanii, balamuthia ...200515811915
isolates of theileria annulata collected from different parts of india show phenotypic and genetic diversity.phenotypic and genetic polymorphism was studied amongst four theileria annulata isolates collected from three different parts of india. amongst various markers studied for the comparison of growth characteristics of schizont cell lines established from these isolates, viability, non-viability counts and nitric oxide (no) production showed significant variation. a negative correlation was observed between no production and mrna expression for tnf-alpha, a potent proinflammatory cytokine related t ...200616513283
natural infection rates and transmission of theileria annulata by hyalomma anatolicum anatolicum ticks in the sudan.hyalomma anatolicum anatolicum nymphs were collected from two localities in the sudan: eddamer in northern sudan and wad-medani in central sudan. they were allowed to moult to adult ticks, which were assessed for theileria infection in their salivary glands using feulgen stain. at eddamer, 49.6% of 123 ticks examined were infected with theileria and the mean intensity of infection was 1.3 (i.e. the number of infected acini/number of infected ticks). at wad-medani, 8.6% of 162 ticks were infected ...200516562733
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 ...200011193668
generation of cytotoxic t lymphocytes and cytostatic acting cells in t. annulata-immune cattle.cattle immunized against theileria annulata with schizont containing autologous cell lines are immune to challenge with a homologous parasite strain. two cell types have been detected in the peripheral blood of the immunized animals: cytotoxic t lymphocytes (ctl) and cytostatic acting cells (cac). killing the target cells by ctl is infection associated and is mhc class i restricted. hence, no cytotoxicity was observed against target cells that were treated with the theilericidal drug buparvaquon ...200011193679
immunization of cattle with nymphal hyalomma anatolicum anatolicum extracts: effects on tick biology.antigens derived from partially engorged nymphs of hyalomma anatolicum anatolicum were used in immunizing crossbred (bos indicus x bos taurus) cattle against larval, nymphal and adult h. a. anatolicum and h. dromedarii. the cattle were either infected with theileria annulata at low parasitaemia or were uninfected. whole nymphal extract (wne), nymphal membrane antigens (nma) and nymphal soluble antigens (nsa) were used for immunization. the group immunized with wne showed significant and better r ...19989719836
a molecular survey of bovine theileria parasites among apparently healthy cattle and with a note on the distribution of ticks in eastern turkey.a survey of theileria parasites in cattle in eastern turkey was carried out using specific polymerase chain reaction. a total of 252 blood samples were collected from clinically healthy cattle between june and july 2004. of 252 blood samples examined, 41 (16%) were positive for piroplasms by microscopy, whereas 114 (45%) were positive for the presence of at least one species of theileria by pcr. the percentages of positive animals for theileria annulata and benign theileria species (theileria se ...200616510248
enhanced lipid peroxide levels in the erythrocytes of calves with haemoglobinuria.eight 6-9 month old calves, showing clinical signs of intermittent haemoglobinuria, even after treatment with an antipiroplasmal drug (4,4-diamidinodiazaminobenzene diaceturate), were examined for oxidative damage to their erythrocytes and the presence of hemoprotozoa in blood smears. four calves without signs of haemoglobinuria served as controls. the blood smears from three of the eight calves contained piroplasms for theileria annulata. irrespective of the presence of piroplasms in their bloo ...200111214672
studies on some blood parameters of crossbred calves with experimental theileria annulata infections.subcutaneous inoculation of 1 ml of ground theileria annulata tick tissue stabilate (0.75 tick equivalent) into crossbred calves (n = 6, average age 53 days) resulted in the development of acute theileriosis. the percentage parasitaemia was 71.7% +/- 3.3% on day 20 after inoculation. macroschizonts were observed in lymphocytes and monocytes. phagocytosed schizonts were observed in neutrophils, along with cytoplasmic vacuolation in monocytes and neutrophils. there was progressive decrease (p < 0. ...200111432430
investigation of blood parasites in livestock infested with argasid and ixodid ticks in egypt.nineteen species and subspecies of ixodid and argasid ticks, hyalomma dromedarii, h. impeltatum, h. anatolicum excavatum, h. a. anatolicum, h. truncatum, h. m. marginatum, h. m. rufipes, h. m. turanicum, boophilus annulatus, rhipicephalus sanguineus, r. turanicus, r. guilhoni, r. camicasi, amblyomma lipidum, a. marmoreum, a. vareigatum, argas persicus, a. hermanii and a. arboreus were collected from different localities in five governorates, giza, sharkia, ismailia, el beheira and sinai. hyalomm ...200111478436
theileria annulata: virulence and transmission from single and mixed clone infections in cattle.theoretically, parasite virulence should be higher for faster growing parasites, and higher in mixed infections compared to single-clone infections. virulence should also be positively correlated to transmission rates. theileria annulata provides a good model system for studying such hypotheses, as parasite replication causes harm to the host, and there is evidence suggesting that the genetic complexity of an infection might affect its virulence. two clones of t. annulata were chosen, one fast g ...200212173404
lymphotactin: a potential mediator of immunity against theileria annulata infection of cattle. 200111463471
a comparison of susceptibilities to infection of four species of hyalomma ticks with theileria annulata.in this comparative study unfed nymphs of four hyalomma tick species (hyalomma anatolicum anatolicum, hyalomma anatolicum excavatum, hyalomma detritum and hyalomma marginatum marginatum) were allowed to engorge on calves experimentally infected with theileria annulata. the infection prevalence in the salivary glands of the adult female and male ticks of each hyalomma species used in the study were assessed. the infection prevalence with t. annulata was high and did not vary markedly in the four ...200312695036
parasitological and clinico-pathological profiles in friesian cattle naturally infected with theileria annulata in saudi arabia.clinico-pathological profiles were studied in adult and young friesian cattle naturally infected with theileria annulata in the qassim region, saudi arabia. sixty-two clinical cases of t. annulata infection in adult and young friesian cattle were diagnosed during the period from august 1999 to july 2000. symptoms observed were marked fever, swelling of superficial lymph nodes, inappetance, tachycardia, dyspnoea and weakness. the most prominent gross pathological features were jaundice, petechial ...200312916695
proteolytic enzyme activity and attenuation of virulence in theileria annulata schizont-infected cells.a field isolate of theileria annulata (uzbek strain) was obtained from calves infected by hyalomma anatolicum ticks collected from an endemic region in uzbekistan. schizont-infected bovine cells that had been established and propagated in cell culture were examined for attenuation both in vivo, by inoculating cells from various passages into calves, and in vitro for metalloproteinase activity. during serial subcultivation a gradual reduction in virulence and in enzyme activity in cells infected ...200312935740
the protozoan parasite, theileria annulata, induces a distinct acute phase protein response in cattle that is associated with pathology.acute phase proteins (app) are synthesised in the liver in response to the systemic presence of high levels of pro-inflammatory cytokines. bacteria are considered to be strong inducers of app whereas viruses are weak or non-inducers of app. very few reports have been published on app induction by parasites. here, we report that the tick-borne protozoan parasite of cattle, theileria annulata, induced an atypical acute phase response in cattle. following experimental infection, serum amyloid a (sa ...200314527523
studies on the epidemiology of tropical theileriosis (theileria annulata infection) in cattle in central anatolia, turkey.an epidemiological survey for theileria annulata infection was conducted in 12 selected villages around ankara in central anatolia, turkey, during the period april 1990 to january 1993. during the survey, 198 cattle of 30 local breeds, 84 holstein-friesian x local breeds and 84 holstein-friesian breed were examined for antibodies to t. annulata and the presence of the vector ticks. four species of hyalomma ticks were identified: hyalomma anatolicum anatolicum, hyalomma anatolicum excavtum, hyalo ...200314690090
a dual role for immunosuppressor mechanisms in infection with theileria annulata: well-regulated suppressor macrophages help in recovery from infection; profound immunosuppression promotes non-healing disease.there is increasing evidence that immune mechanisms are involved in the pathogenesis of many parasitic infections, including infections with the tick-borne protozoan theileria annulata. the initial stages of tropical theileriosis are characterised by the induction of a non-specific lymphoproliferation by schizont-infected cells which is believed to disrupt antigen recognition and interfere with protective immune responses. this study examined the possibility that cattle do not always succumb to ...200212107474
simultaneous detection of anaplasma and ehrlichia species in ruminants and detection of ehrlichia ruminantium in amblyomma variegatum ticks by reverse line blot hybridization.the detection of anaplasma and ehrlichia species is usually based on species-specific pcr assays, since no assay is yet available which can detect and identify these species simultaneously. to this end, we developed a reverse line blot (rlb) assay for simultaneous detection and identification of anaplasma and ehrlichia species in domestic ruminants and ticks. in a pcr the hypervariable v1 region of the 16s ribosomal rna (rrna) gene was amplified with a set of primers unique for members of the ge ...200212243899
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