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ultrastructure of babesia major vermicules from the tick haemaphysalis punctata as demonstrated by negative staining.the ultrastructure of babesia major vermicules was studied in samples derived from the haemolymph of haemaphysalis punctata adults and negatively stained with phosphotungstic acid. most of the organelles observed were typical of those found in apicomplexan parasites. these were the apical complex with the polar ring and the ribs, micronemes and subpellicular microtubules. the number of ribs was 27 or 28. the outer membrane of the pellicle was composed of a large number of fibrils running along t ...197877093
[light microscopic studies on the development of theileria annulata (dschunkowsky and luhs, 1904) in hyalomma anatolicum excavatum (koch, 1844). ii. the development in haemolymph and salivary glands (author's transl)].fully differentiated kinetes, average length 17.6 micrometer, appeared in the haemolymph of engorged nymphs usually 17 to 20 days after repletion. kinetes were observed at first in the salivary glands on day 18 after repletion. the kinetes then transformed into fission bodies of about 10 micrometer in diameter, mainly in type iii alveoli and less frequently in type ii alveoli. the fission bodies grew up to a size of about 20 micrometer after several divisions of their nucleus. at this time the t ...197899896
development of infectivity in hyalomma detritum (schulze, 1919) ticks infected with theileria annulata (dchunkowsky and luhs, 1904).the time-course for the development of infectivity was studied in hyalomma detritum ticks fed as pre-imagoes on calves infected with theileria annulata. unfed adults derived from infected nymphs were non-infectious when inoculated into susceptible calves, whereas ticks of both sexes that had fed for 2-3 days or longer on calves or rabbits were always infectious. some adults fed for only 1-2 days were infectious, whereas others were not. as few as 2 ticks were capable of infecting susceptible cal ...1978107504
infectivity of ground-up tick supernates prepared from theilerai annulata infected hyalomma anatolicum anatolicum.groups of theileria annulata infected hyalomma anatolicum anatolicum adults prefed on a calf for 1 to 6 days were separately ground in tissue culture medium-199, supplemented with bovine albumin powder, fraction-v. supernatant fluid was collected, made up with additional medium, so that each millilitre represented material from 25 ticks, and was injected subcutaneously into groups of cross-bred male calves. the results indicated that ground-up tick supernate (guts) prepared from unfed ticks was ...1979111383
immunization against bovine tropical theileriosis, using 60co-irradiated infective particles of theileria annulata (dschunkowsky and luhs 1904) derived from ticks.portions of ground supernate material from theileria annulata-infected and prefed adults of the hyalomma anatolicum anatolicum were irridiated by 60co source at 0, 3, 5, 6, 7, or 9 krads. these portions were injected subcutaneously into different groups of cross-bred calves. the calves injected with 0-, 3-, or 5-krad irradiated tick supernate had severe reactions (rectal temperature 39.8 to 41.6 c, two- to fourfold enlargement of prescapular lymph gland, mean peak parasitemia 27.3% to 32.5% infe ...1979112890
the production of nymphs of hyalomma anatolicum anatolicum for experimental infection with theileria annulata.methods are described for the production of nymphs of hyalomma anatolicum anatolicum for later use in transmission experiments with theileria annulata where the timing of the application of nymphs to infected cattle needs to be accurately controlled. larvae are fed on the torsos of rabbits where approximately 98% undergo a two-host feeding cycle. this cycle is interrupted 2 days after the first larvae moult into nymphs by killing the rabbits and the nymphs are then collected with a suction pump. ...1979116404
isoenzyme variation in piroplasms isolated from bovine blood infected with theileria annulata and t parva.blood from calves infected with theileria annulata and t parva was freed from host cell elements and the piroplasms liberated from the red cells by ammonium chloride lysis. lysates of the purified piroplasms and control host cell material were examined electrophoretically for several enzymes. zymograms stained for glucose phosphate isomerase showed distinct differences between the host cell enzyme pattern and parasite enzyme patterns. the isoenzyme pattern of t annulata piroplasms differed from ...1979120575
virulence and immunogenicity of cultured theileria annulata schizonts. 1979122001
atypical mitochondria in an intracellular protozoan (theileria annulata, apicomplexa). identification by ultracytochemistry. 1978215921
electron microscopic studies of the development of kinetes in theileria annulata dschunkowsky & luhs, 1904 (sporozoa, piroplasmea).gamogony of theileria annulata dschunkowsky & luhs occurs within the intestine of nymphs of the tick hyalomma anatolicum excavatum koch. after the 5th day post repletionem (p.r.) of the ticks spherical and ovoid parasites were found within the intestinal cells. these stages were thought to represent fertilized macrogametes. these underwent a transformation process leading ultimately to the differentiation of a motile stage, the kinete, which leaves the intestinal cells on the 14th-17th day p.r. ...1977407352
specific igm and iggantibodies in cattle immunized or infected with theileria annulata.antibodies of the igm and igg classes were detected in cattle inoculated with living or dead theileria annulata. both types of antibody appeared from 18 to 36 days after inoculation and persisted for up to 120 days, the longest period tested. no diagnostic application could be assigned to the differentiation of the 2 classes of antibody.1978417441
[fine structural study on the erythrocytic stages of theileria annulata (dschunkowsky, luhs, 1904) (author's transl)]. 1977562008
cell-mediated immunity in tropical theileriasis (theileria annulata infection).migration of peripheral leucocytes collected from theileria annulata carrier cattle was inhibited in the presence of piroplasmal antigen. the degree of inhibition was antigen density dependent. the same antigen did not inhibit migration of leucocytes obtained from clean animals, raised under tick-free conditions. the carrier animals exhibited typical skin sensitivity reaction on intradermal inocluation of the piroplasmal antigen. the known negative animals failed to evince a similar reaction.1977605307
immunisation of cattle against tropical theileriosis (theileria annulata infection) by "infection-treatment" method. 1977606142
studies on the relationship between the quantum of infection and the ensuing reaction of cattle infected with theileria annulata. 1977610628
symptoms and pathology of experimental bovine tropical theileriosis (theileria annulata infection).bovine tropical theileriosis (theileria annulata infection) is of great economic importance to several countries of asia and africa where millions of cattle are at risk of exposure to this disease. the authors describe symptoms, sequence of appearance of the parasite and pathology of the infection by three virulent strains of the parasite in fully susceptible calves. symptoms observed were: enlargement of local lymph gland, fever, haemorrhages on visible mucous membranes and sometime on skin, an ...1977613962
[clinical study on experimental theileria annulata infections of cattle. 1. clinical-chemical studies].the extent of liver and kidney damage in 10 young steers, infected with a stabilate of theileria annulata, was estimated by the determination of enzymes (got, gpt, sdh, ald), serum levels of bilirubin and urea. at the same time the effectiveness of some liver protecting medical agents was tested. the following results were obtained: change in the activity of the enzymes got, sdh and ald and the increase of bilirubin during the advanced course of the disease are indicative of severe tissue damage ...1978623617
[clinical studies on theileria annulata infection in cattle. ii. hematological studies]. 1978629735
chemoprophylaxis with tetracycline drugs in the immunisation of cattle against theileria annulata infection. 1978748220
on the life cycle of theileria annulata (dschunkowsky and luhs, 1904) in the midgut and hemolymph of hyalomma anatolicum excavatum (koch, 1844). 1975810989
[virulence and immunogenic properties in strains of theileria annulata]. 1975813362
[immunofluorescence reaction in the study of the antigenic and immunogenic properties of theileria annulata]. 1975813364
studies on the development of theileria annulata dschunskowsky and luhs, 1904 in the tick--hyalomma anatolicum anatolicum koch, 1844.the endogenous development of theileria annulata in the vector tick--hyalomma anatolicum anatolicum has been described. parasites within and outside the erythrocytes were seen in the gut contents of larvae and nymphs immediately after their removal from the infected cattle but not after 24 hours. two bodies resembling the intra-erythrocytic stage of the parasite, lying close to each other were seen near the gut epithelium of a larva on the 4th day of its dropping off the infected host. neither m ...1975813551
[cultivation of theileria annulata in tissue culture]. 1975814691
[light microscopic studies on the development of theileria annulata (dschunkowsky and luhs, 1904) in hyalomma anatolicum excavatum (koch, 1844). i. the development in the gut of engorged nymphs (author's transl)].a laboratory strain of h. a. excavatum was selected on high susceptibility for t. annulata through several generations. giemsa-stained smears and wet smears of gut and gut content were studied. after engorgement of erythrocytic stages of t. annulata by the nymphs the following development was observed: 1. erythrocytic merozoites developed to slender, spindleshaped "microgamonts" in the gut 24 to 96 hours after repletion (p. repl.). spherical stages with a conspicuous spike developed at the same ...1975814732
[electron microscope studies on development stages of theileria annulata (dschunkowsky, luhs, 1904) in the intestine and haemolymph of hyalomma anatolicum excavatum (koch, 1844) (author's transl)].for the first time developmental stages of theileria within the intestine and haemolymph of ticks were studied by electron microscopy. on the 1st-6th day post repletionem the intestine of the ticks contained humerous tages, which were very similar to microgamonts and microgametes of haemosporidia. later, on the 14th-19th day p.r. ookinete-like stages ere found in the haemolymph of ticks. from these results it seemed likely that gamogony of theileria takes place in the intestine of ticks. in more ...1975814733
[ultrastructure of theileria annulata]. 1976818783
the transmission of theileria annulata to a rabbit by the larvae of the tick hyalomma rufipes.a new zealand white rabbit on which larvae of hyalomma rufipes were fed died of theileriosis due to theileria annulata 22 days after the larvae had fed. the larvae were direct progeny of an enorged female collected from trade cattle in the veterinary control post at ibadan. the danger attending the feeding on rabbits of first progeny of ticks collected from cattle in countries where some tick-borne diseases are endemic is highlighted. the possibility of transovarial transmission of theileria is ...1977839720
[therapy and prevention of theileria annulata diseases of cattle with resochin "bayer"]. 1977901403
infective theileria annulata in the tick without a blood meal stimulus. 1977927515
the pathogenesis of anaemia in theileria annulata infection.calves infected by a field strain of theileria annulata developed severe anaemia, which was accompanied by bilirubinaemia and the appearance of free serum autohaemagglutinin antibodies. animals infected with an agamogenous strain (lacking erythrocytic forms) also became anaemic. anisocytosis appeared in all infected animals but regenerative anaemic lesions were observed only in those which survived the infection. in this group of animals anaemia was accompanied by bilirubinaemia and the developm ...1976935669
the application of imidocarb dipropionate for the control of theileria annulata infection in egyptian cattle used for testing rinderpest vaccine. 1976963507
immunisation against bovine tropical theileriasis (theileria annulata infection).fully susceptible cross-bred calves, six to nine months of age, were immunised by tick-induced theileria annulata infection treated with chlortetracycline at 16 mg/kg body weight for four, eight or 16 days. the infections were induced with 10 ticks (hyalomma anatolicum anatolicum) or 30 ticks (h dromedarii). the recovered calves were tested for immunity to homologous severe challenge, 50 or 73 days after the first infection. the reaction of the calves to infections was evaluated by noting the pr ...1976968181
vaccination against bovine tropical theileriasis (theileria annulata). 19761004558
effects of 60co irradiation of the early developmental stages of an ixodid tick, hyalomma anatolicum.various developmental stages of hyalomma anatolicum were subjected to a range of doses of 60co radiation from 0-10 000 r, and their subsequent development was observed. some of these ticks were infected with theileria annulata. doses of 2000 r and over prevented all but a very limited development of ticks. after 1000 r a proportion of exposed individuals continued development in a near-normal manner. lower doses had proportionately less effect. 1000 r to ticks infected with t. annulata failed to ...19761083381
transstadial transmission of theileria annulata through common ixodid ticks infesting indian cattle.transstadial transmission of theileria annulata with hyalomma anatolicum anatolicum, h. dromedarii and h. marginatum isaaci, and haemaphysalis bispinosa, rhipicephalus haemaphysaloides haemaphysaloides and boophilus microplus was determined. it was found that the infection was successfully transmitted by h. a. anatolicum from larva to nymph and nymph to adult in all attempts. when larvae were fed on an infected calf the succeeding adults transmitted the infection when the intervening nymphs fed ...19751178216
common and stage-specific antigens of theileria annulata.western blot analysis of theileria annulata antigens was carried out using sera collected from cattle which had been immunised and challenged with either t. annulata sporozoites or schizont-infected cells. three antigens between 71 and 73 kda proved to be common to the three stages of parasite studied: sporozoites, schizonts and piroplasms. an antigen was found at 32 kda which was specific to t. annulata piroplasms. results were reproducible using sera from morocco and the uk. at least one of th ...19921280878
induction of the 68 kda major heat-shock protein in different theileria annulata- and virus-transformed bovine lymphoblastoid cell lines.expression of the major inducible heat-shock protein of 68 kda (hsp68) has been analyzed in peripheral blood mononuclear cells (pbmc) from cattle and in six theileria annulata- and two bovine leukemia virus-transformed bovine lymphoblastoid cell lines (bolcl). by metabolic labeling, hsp68 could be detected in pbmc and bolcl only after heat-shock, but not under normal culture conditions. immunoblot analysis with an hsp68 reactive monoclonal antibody similarly revealed a strong hsp68 response afte ...19921325086
effect of buparvaquone on the expression of interleukin 2 receptors in theileria annulata-infected cells.theileria annulata-infected cells were cultured in the presence or absence of human recombinant interleukin 2 (hril-2). this growth factor proved to be capable of enhancing the growth of the infected cells: its effect was marked, particularly when the cells were seeded at low densities, and it varied from cell line to cell line. the infected cells produced a factor that possessed the biological activities of il-2, since their supernatants could enhance the proliferation of concanvalin a-stimulat ...19921409527
tropical theileriosis in bos taurus and bos taurus cross bos indicus calves: response to infection with graded doses of sporozoites of theileria annulata.this work extends basic knowledge of tropical theileriosis in taurine and crossbred cattle. infection of bos taurus and bos taurus cross bos indicus (sahiwal) calves with graded doses of sporozoites of theileria annulata (hissar), an indian stock of the parasite, showed the following to be dose dependent in both cattle types: the time to appearance and population size of macroschizonts, microschizonts and piroplasms, time and severity of pyrexia, anaemia manifested by erythrocyte counts and haem ...19921439213
the epidemiology of tropical theileriosis (theileria annulata infection in cattle) in an endemic area of morocco.a longitudinal study of tropical theileriosis was performed on 12 farms in the doukkala region of morocco during 1990. adult hyalomma detritum detritum were collected between march and early october and a peak in numbers was observed at the end of june. nineteen percent (24/127) were infected with theileria species and, amongst these, over 50% had five or more sporoblasts in their salivary glands (range 1-151). hyalomma d detritum larvae and nymphs were found on cattle between september and earl ...19921441192
theileria annulata-infected cells produce abundant proteases whose activity is reduced by long-term cell culture.lysates of theileria annulata-infected bovine lymphoblastoid cells and their uninfected counterparts were tested for protease activity using gelatin substrate sds-page. the infected cells produced a number of extra activities at ph 8.0 in the presence of ca2+. calcium was found to enhance the activities but was not an absolute requirement. studies using inhibitors, including e64, 3,4-dichloroisocoumarin, pepstatin and 1, 10-phenanthroline suggested that the activities were metalloproteases. we a ...19921461683
mimicry of elastin repetitive motifs by theileria annulata sporozoite surface antigen.theileria annulata is an important pathogen of cattle in the tropics. the gene sequence of a sporozoite surface antigen (spag-1) is reported. data is also presented demonstrating that spag-1 is synthesised as a large precursor. this antigen, which is a candidate for inclusion in a subunit vaccine, shows a remarkable degree of molecular mimicry to the extracellular matrix protein elastin. it contains both repetitive motifs pgvgv and vgvapg. immunofluorescence using a monoclonal antibody against v ...19921501630
characterisation of a gene for a cysteine protease from theileria annulata. 19921518523
ribosomal dna sequence comparison of babesia and theileria.previous studies on the taxonomy of babesia spp. (phylum apicomplexa) using morphological and life cycle characteristics have resulted in their classification into 3 subgenera, with the genus theileria being most closely related to them. using a strategy based on the direct sequence analysis of products derived by asymmetric pcr to determine the nucleotide sequences, we have tested the validity of this classification by sequencing the small subunit ribosomal rna genes amplified from 2 babesia sp ...19921518535
the nucleotide sequence of the small subunit ribosomal rna gene from symbiodinium pilosum, a symbiotic dinoflagellate.the complete sequence of the small subunit ribosomal rna (ssu rrna) gene was determined for the symbiotic dinoflagellate symbiodinium pilosum. this sequence was compared with sequences from two other dinoflagellates (prorocentrum micans and crypthecodinium cohnii), five apicomplexa, five ciliata, five other eukaryotes and one archaebacterium. the corresponding structurally conserved regions of the molecule were used to determine which portions of the sequences could be unambiguously aligned. phy ...19921525867
cell-mediated immune responses to sporozoites and macroschizonts of theileria annulata.the nature of cell-mediated immune (cmi) responses was studied in cross-bred bovine calves, immunised by attenuated and allogeneic macroschizonts of theileria annulata. the cmi responses were also investigated in calves, destined to survive or die of tropical theileriosis (theileria annulata) induced by a virulent dose of sporozoites or macroschizont-infected lymphoblasts. calves suffering fatal theileriosis showed poor cmi response. microcytotoxicity assay revealed an enhanced population of spe ...19921561760
characterisation of the gene encoding a candidate vaccine antigen of theileria parva sporozoites.we have cloned and characterised the gene encoding the 67-kilodalton stage-specific surface antigen, p67, of theileria parva (muguga) sporozoites. the gene which is present in a single copy, is divided into 2 exons by an intron 29 bp long and is transcribed into mrna of about 2500 nucleotides. the gene is present in all stocks of t. parva and there is a related gene in theileria annulata. the deduced amino acid sequence of 709 residues predicts that p67 is a membrane protein and that it lacks ta ...19921565135
disruption of synchrony between parasite growth and host cell division is a determinant of differentiation to the merozoite in theileria annulata.the multinucleated macroschizont stage of the protozoon theileria annulata is an intracellular parasite of bovine leukocytes. the parasite induces the host cell to proliferate, and divides in synchrony with the immortalised host cell. differentiation to the next stage occurs within the host cell culminating in the release of merozoites and destruction of the leukocyte. in this study clones of theileria annulata macroschizont-infected cell lines were isolated by limiting dilution and tested for d ...19921569131
cytokines inhibit the development of trophozoite-infected cells of theileria annulata and theileria parva but enhance the proliferation of macroschizont-infected cell lines.the following bovine (bo) and human (hu) cytokines--bo rtnf-a, bo rifn-g, hu ifn-a, hu ril-1, hu ril-2--significantly inhibited the in vitro development of trophozoite-infected cells of three stocks of theileria annulata and of theileria parva (muguga). however, none of these cytokines inhibited the proliferation of established t. annulata or t. parva macroschizont-infected cell lines. indeed, bo rtnf-a and hu ril-2 consistently enhanced the proliferation of macroschizont-infected cell lines of ...19921570169
stage-specific responses following infection with theileria annulata as evaluated using elisa.an enzyme-linked immunosorbent assay (elisa) using sporozoite, schizont and piroplasm antigens was developed to study the immune response of animals that had been immunised with either theileria annulata sporozoites or schizont-infected cells and then challenged with sporozoites. the aim was to identify the most suitable antigen for a routine screening test and to compare the sensitivity of the latter with that of the indirect fluorescent antibody test (ifat). as determined by elisa, cattle prod ...19921584746
hematological study of water buffalo (bubalus bubalis) during theileriosis (theileria annulata). 19921626870
anti-lymphocyte antibodies generated in animals immunised with theileria annulata-infected cells.complement fixing antibodies were measured in sera from animals immunised with either theileria annulata sporozoites or autologous or allogeneic schizont-infected mononuclear cells using a complement-mediated micro-cytotoxicity test. the test demonstrated the presence of anti-lymphocyte antibodies in allogeneic cell-immunised animals, which were not detectable in autologous cell- or sporozoite-immunised animals; also that these antibodies were directed to t. annulata-infected and (mhc) class i a ...19921632077
growth of theileria annulata and theileria parva macroschizont-infected bovine cells in immunodeficient mice: effect of irradiation and tumour load on lymphocyte subsets.bovine cells infected with macroschizonts of the protozoan parasites theileria annulata and theileria parva formed solid tumours when injected into irradiated balb/c and irradiated balb/c nude mice. t. annulata tumours grew more vigorously than t. parva tumours, when initiated with similar doses of infected cells in mice exposed to the same doses of gamma-irradiation. in irradiated balb/c mice, tumours of both species of parasites began to regress 2-3 weeks after injection of cells but grew with ...19921644524
characterisation of an extrachromosomal dna element from theileria annulata.extrachromosomal nucleic acid elements are found in all organisms, commonly as organelle, viral or plasmid genomes. in this paper we describe the initial characterisation of a novel 6.5-kb linear, double-stranded extrachromosomal element from theileria annulata, and a 2.6-kb rna species. the dna element is present in different stages of the life cycle and in different stocks of the parasite. northern blots of total rna isolated from different stages of the parasite, probed with the purified elem ...19901691446
production of interferons by bovine and ovine cell lines infected with theileria annulata or theileria parva.three bovine cell lines and four ovine cell lines infected with theileria parva or theileria annulata were examined for the production of interferon (ifn). biologically active ifn was detected in the tissue culture supernatants of four of the cell lines. only one, a bovine cell line infected with t. parva, produced ifn-gamma as measured by specific neutralization with a monoclonal antibody to bovine ifn-gamma. this observation was confirmed by analysing rna from the cell lines on northern blots ...19911712932
theileria annulata: alterations in phosphoprotein and protein kinase activity profiles of infected leukocytes of the bovine host, bos taurus.the phosphoprotein profiles of t. annulata-infected and uninfected leukocyte cell lines were compared by both in vivo and in vitro labeling assays. three phosphoproteins were unique to t. annulata-infected cells, while a further two were quantitatively increased relative to uninfected cells. in addition, two proteins were present and phosphorylated only in the uninfected cell lines, suggesting either a repression of these proteins or their dephosphorylation upon infection of the host cell by the ...19921740181
effect of temperature on transtadial transmission of theileria annulata in hyalomma anatolicum anatolicum ticks.the effect of temperature on the transtadial transmission of theileria annulata in hyalomma anatolicum anatolicum was studied. variation in temperature (4-40 degrees c) had a significant effect on moulting rate of the ticks and transmission of theilerial parasites from nymphs to resultant adults. the temperatures above 40 degrees c and below 12 degrees c prevented moulting. maximum infection levels were obtained in salivary glands of adult ticks when the infected engorged nymphs were incubated a ...19911763485
the gene for apocytochrome b of theileria annulata resides on a small linear extrachromosomal element. 19911779987
effect of cyclosporin a on the proliferation of bovine lymphocytes to concanavalin a and on the growth of theileria annulata-infected bovine cells.after being inoculated by hyalomma ticks, the sporozoites of theileria annulata invade bovine lymphocytes, where they subsequently differentiate to schizonts. the infected cells are induced to a continuous proliferation which can be enhanced by human recombinant interleukin 2 (hril-2). in the present study, we examined the influence of cyclosporin a (csa) on the growth of schizont-containing cells and compared with its effect on bovine peripheral blood lymphocytes (pbl) responding to concanavali ...19911796237
ribosomal rna sequences of sarcocystis muris, theileria annulata and crypthecodinium cohnii reveal evolutionary relationships among apicomplexans, dinoflagellates, and ciliates.sarcocystis muris is a coccidium with a two-host life cycle involving the domestic cat and the mouse, mus musculus. s. muris and theileria annulata belong to the phylum apicomplexa, but the latter organism is a tick-borne protozoon in the subclass piroplasmea and causes tropical theileriosis in cattle. the small-subunit ribosomal rna (16s-like rrna) coding regions of these organisms as well as that of the free living dinoflagellate crypthecodinium cohnii were amplified using polymerase chain rea ...19911904987
immunoprophylaxis against theileria annulata with protein from plasma membrane of infected lymphoblasts.cross-bred (bos taurus male x bos indicus female) calves were protected against the homologous sporozoite-induced challenge of theileria annulata when immunised with protein from the plasma membrane of macroschizont-infected lymphoblasts of allogeneic origin. however, such protection was parasite-strain specific with the plasma membrane originating from lymphoblasts infected and transformed by the same isolate of t. annulata sporozoites. no protection ensued when the infected lymphoblasts and sp ...19911910224
expression of tac antigen component of bovine interleukin-2 receptor in different leukocyte populations infected with theileria parva or theileria annulata.the tac antigen component of the bovine interleukin-2 receptor was expressed as a cro-beta-galactosidase fusion protein in escherichia coli and used to raise antibodies in rabbits. these antibodies were used for flow cytofluorimetric analysis to investigate the expression of tac antigen in a variety of theileria parva-infected cell lines and also in three theileria annulata-infected cell lines. cells expressing tac antigen on their surface were found in all t. parva-infected cell lines tested wh ...19901979317
chemotherapeutic value of parvaquone and buparvaquone against theileria annulata infection of cattle.parvaquone (bw993c), 2-cyclohexyl-3-hydroxy-1,4-naphthoquinone, and buparvaquone (bw720c) 2-(trans-4-t-butylcyclohexyl-methyl)-3-hydroxy-1,4-naphthoquinone, were evaluated to determine their therapeutic efficacy in the treatment of theileriosis caused by theileria annulata infection in cattle in iran. one hundred and fifty-nine pure and crossbred bos taurus cattle, experimentally or naturally infected with t annulata, were treated. parvaquone was injected into 86 animals with up to three doses o ...19912034901
evolutionary relationships of avian eimeria species among other apicomplexan protozoa: monophyly of the apicomplexa is supported.direct, reverse transcriptase-mediated, partial sequencing of the small-subunit (16s-like) ribosomal rna (srrna) of eimeria tenella and e. acervulina was performed. sequences were aligned by eye with six previously published, partial or complete srrna sequences of apicomplexan protists (plasmodium berghei, theileria annulata, cryptosporidium sp., toxoplasma gondii, sarcocystis muris, and s. gigantea). six eukaryotic protists (a slime mold, a yeast, two dinoflagellates, and two ciliates) acted as ...19912072862
the effects of bovine tick resistance on the susceptibility of hyalomma anatolicum anatolicum to infection with theileria annulata (ankara).two bos taurus calves were made resistant to tick infestation by exposing them to approximately 500 rabbit-reared nymphs of hyalomma anatolicum anatolicum twice at a 2-week interval. these two calves, together with a tick-susceptible control calf, were inoculated with a stabilate of theileria annulata (ankara). patent infection resulted in all three calves. seven-hundred and fifty gerbil-reared nymphs were then applied on each of these calves as well as another tick-susceptible calf that was the ...19902107619
developmental expression of a theileria annulata merozoite surface antigen.culture of a lymphoblastoid cell line infected with the macroschizont stage of the protozoan parasite theileria annulata at 41 degrees c induces differentiation to the next stage, the merozoite. we have demonstrated that this development results in the loss of monoclonal antibody epitopes associated with the macroschizont stage, and the appearance of epitopes associated with the piroplasm (the intra-erythrocytic stages). one of the monoclonals (5e1) was shown by immunoelectron microscopy to bind ...19902112226
buparvaquone but not cyclosporin a prevents theileria annulata-infected bovine lymphoblastoid cells from stimulating uninfected lymphocytes.the influence of buparvaquone on the morphology, proliferation, and stimulation with t and b cell mitogens of theileria annulata-infected cells was studied. in addition, the stimulatory capacity of the infected cells before and after treatment with buparvaquone or cyclosporin a (csa) was also examined and compared to that of cona-stimulated bovine peripheral blood cells (pbl). after incubation of the cells for 4 days with buparvaquone only few schizonts were detectable in the cells. prolongation ...19902116660
establishment of theileria-infected bovine cell lines in scid mice.bovine cells transformed by infection with the protozoan parasite theileria annulata were inoculated subcutaneously or intraperitoneally into c.b.-17 scid mice. mice injected subcutaneously developed solid tumours at the injection site, whilst those injected intraperitoneally developed ascites. schizont-infected cells were found in other tissues: infected cells spread much more easily from the intraperitoneal site. karyotyping of cells isolated from tumours showed no evidence of transfer of para ...19902117267
comparison of three methods for initiating in vitro cultures of theileria annulata schizonts.three methods for initiating in vitro cultures of theileria annulata from infected cattle were compared: 1) separation of buffy coat cells by centrifugation in a plastic syringe; 2) separation of lymphocytes by a commercial ficoll-paque gradient and 3) trypsinization of liver biopsy material. successful cultures were obtained in 26 out of 48 trials (54 p. 100) by method 1, in 28 out of 56 trials (50 p. 100) by method 2 and 17 out of 21 trials (81 p. 100) by method 3. once established, cultures, ...19902120747
control of tropical theileriosis (theileria annulata infection) of cattle.tropical bovine theileriosis caused by theileria annulata and transmitted by ticks of the genus hyalomma may be controlled by one or more of the following methods: i) management, with particular emphasis on movement control; ii) vector control by application of acaricides, preventing transmission of disease; iii) treatment of clinical disease using specific chemotherapeutics; iv) immunization with live vaccines; and v) the use of cattle resistant to ticks or the disease. of these the most import ...19902126619
methods currently used for the control of theileria annulata: their validity and proposals for future control strategies.the development of a cell culture vaccine against tropical theileriosis in india is described. observations on the experiments conducted for the standardization of dose, storage temperature, evaluation of immune response, cross-protection response and field immunization trials are summarized. future strategies for epidemiological studies and the control of tropical theileriosis are discussed.19902126620
control of theileria species (other than east coast fever and theileria annulata infection), ehrlichia and tick toxicosis: present situation and proposals for future control strategies. 19902126621
theileria annulata: control measures, diagnosis and the potential use of subunit vaccines.theileria annulata is an important pathogen of domestic bovidae across a broad region of the world with some 250 million cattle at risk. our basic knowledge of the incidence and mortality is reviewed together with an outline of current control measures, including the use of acaricides, chemotherapy and attenuated cell line vaccines. the limitations and potential problems of these control measures are discussed and considered in relation to the use of a subunit vaccine. research over the last ten ...19902132687
observations on the in vitro multiplication of bovine lymphoid cells infected with theileria annulata schizonts.the multiplication of a bovine lymphoid cell line infected with theileria annulata schizonts was studied. in cells dividing mitotically, the schizont occupied a central position during the late stages of the division and was shared by the two newly formed cells. binucleated cells with schizonts located between the nuclei were also observed. no definitive conclusions can be drawn as to whether these cells are stages in amitotic division or result from fusion of infected cells. wide variations in ...19902132788
[presence of theileria annulata in mauritania].a fatal case of bovine theileriosis by theileria annulata is reported from mauritania in a friesian cow born in a dairy farm in nouakchott. the farm was originally established with cattle imported from france. specific diagnosis was based on piroplasm morphology and on high specific antibody titres in some of the animals. the only tick found in the herd was hyalomma dromedarii. four of 49 local zebus sampled at random in the south of the country had high specific antibody titres to t. annulata, ...19902132789
parasite-accessory cell interactions in theileriosis. antigen presentation by theileria annulata-infected macrophages and production of continuously growing antigen-presenting cell lines.theileria annulata, a protozoan parasite of cattle, infects major histocompatibility complex (mhc) class ii+ cells, particularly macrophages, and transforms them into continuously growing cell lines. we examined the effects of parasitism by t. annulata on antigen-presenting cell function. t. annulata-infected cells (tah) presented ovalbumin (as measured by [3h]thymidine incorporation) to both resting autologous bovine t cells and ovalbumin-specific bovine cd4+ t cell lines. however, the former c ...19902253687
treatment of bovine tropical theileriosis with buparvaquone.the antitheilerial activity of buparvaquone in crossbred male calves, experimentally infected with theileria annulata (izatnagar isolate) has been tested. animals were treated intramuscularly at the dose rate of 2.5 mg/kg1 body weight. a single dose of the drug administered during the phase of ascending parasitaemia cured all the infected calves while all the untreated infected control calves died.19902321263
chemoimmunoprophylaxis against bovine tropical theileriosis in young calves: a comparison between buparvaquone and long-acting oxytetracycline.eighteen seven to 21-day-old crossbred (bos taurus cross bos indicus) calves were allocated to four groups (a to d). groups a and b each consisted of six calves and groups c and d three calves each. each calf in groups a, b and c was inoculated with ground-up tick supernate (guts) equivalent to two infected acini prepared from theileria annulata-infected hyalomma anatolicum anatolicum. each calf in group a was also given a single intramuscular injection of buparvaquone, 2.5 mg kg-1 bodyweight si ...19902382047
the integrity of host lymphocyte plasmalemma during its invasion by theileria annulata sporozoites as demonstrated by ruthenium red staining.the integrity of host lymphocyte plasma membrane during its invasion by theileria annulata sporozoites was examined in an in vitro system using ruthenium red staining. it was demonstrated that during interiorisation of the sporozoites, the dye was completely excluded from the intracellular milieu, indicating that the continuity of the host-cell plasmalemma was not disrupted throughout the process of penetration, and confirmed a previous observation that the fragmentation of the host lymphocyte m ...19852408373
identification of infection-associated antigens in theileria annulata transformed cells.the protozoan parasite theileria annulata causes a severe disease of cattle in tropical countries; one stage in the parasite life cycle involves the transformation of bovine lymphocytes leading to rapid lymphoproliferation. immunity to this disease is largely cell mediated and directed against the infected lymphocyte. in this paper we report the identification of three classes of infection specific antigen (using monoclonal antibodies) one of which is found on the surface of the lymphocyte. such ...19862421227
the effect of mhc compatibility between parasite-infected cell line and recipient in immunization against tropical theileriosis.lymphoblastoid cell lines, infected and transformed in vitro by a moroccan stock of theileria annulata, infected and immunized susceptible taurine cattle, at cell doses of 10(8), 10(6), 10(4) and 10(2), regardless of whether the recipients were bola matched or mismatched to the donor cell line. the mhc relationship between the cell line and recipient did affect the severity of the clinical response to cell line immunization which may reflect differences in the specific priming of the immune resp ...19892494633
the development and specificity of cytotoxic cells in cattle immunized with autologous or allogeneic theileria annulata-infected lymphoblastoid cell lines.two groups of animals were immunized with either 10(6) autologous or 10(6) allogeneic theileria annulata-infected lymphoblastoid cells cultured in vitro. the development and specificity of cytotoxic cells generated in vivo were measured throughout immunization and challenge using a panel of target cells that were either theileria-infected or uninfected blast cells of known bovine lymphocyte antigen (bola) specificities. after inoculation of the cell lines the two groups showed distinct differenc ...19892494634
characterization of surface polypeptides on different life-cycle stages of theileria annulata.we describe the characterisation of polypeptides located on the surface of theileria annulata sporozoites, macroschizonts, piroplasms and infected lymphoblastoid cells using surface iodination techniques. the sporozoite stage exhibited a complex profile of surface polypeptides. however, using data from experiments with defined monoclonal antibodies, the sporozoite surface appeared to be composed of several distinct groups of related polypeptides. analysis of the macroschizont detected seven surf ...19892499787
theileria annulata sporozoite surface antigen expressed in escherichia coli elicits neutralizing antibody.theileria annulata is an economically important protozoan parasite that threatens an estimated 250 million cattle with the disease tropical theileriosis. development of a defined subunit vaccine is one means of trying to develop control measures against the disease. to this end we have characterized a surface antigen complex of the infective stage (sporozoite), by using a monoclonal antibody that neutralizes sporozoite infectivity in vitro. we have cloned the gene coding for this complex and hav ...19892499888
in vitro infection of bovine alloreactive cytotoxic t cell lines with sporozoites of theileria annulata and t parva.bovine alloreactive cytotoxic lymphocyte (ctl) lines of known target specificity were infected in vitro with sporozoites of theileria annulata and t parva and cultured in limiting dilution. the phenotypes of the ctl lines both pre- and post infection were assessed using a panel of monoclonal antibodies specific for defined bovine lymphocyte subpopulations. the effector function of the resultant infected cell lines was determined using a cr51 release assay and compared to the uninfected control c ...19892500685
the effect of dose and line on immunisation of cattle with lymphoblastoid cells infected with theileria annulata.thirty-one friesian calves in morocco susceptible to tropical theileriosis were protected against a lethal sporozoite challenge by prior infection with lymphoblastoid cell lines infected and transformed in vitro by a moroccan stock of theileria annulata. the challenge infection of cryopreserved sporozoites killed all four susceptible control calves within 20 days. four schizont-infected cell cultures at passage 3 were inoculated at four different doses, 10(8), 10(6), 10(4) and 10(2), into pairs ...19892503921
sequence and expression of a gene from theileria annulata coding for a 70-kilodalton heat-shock protein.a library consisting of randomly sheared theileria annulata genomic dna fragments in the vector lambda gt11 was screened with a drosophila dna segment containing the coding region of the 70-kda heat-shock protein (hsp) gene. a positive recombinant was isolated and subjected to nucleotide sequence analysis. the dna segment contains an open reading frame coding for a 71-kda protein strongly homologous to hsp 70 from other organisms. using this dna as a probe, a homologous 2.5-kb rna species was de ...19892515435
infection of bovine monocyte/macrophage populations with theileria annulata and theileria parva.infection and transformation of cells of the bovine immune system by theileria annulata and t. parva were compared. preliminary experiments with mammary gland macrophages indicated that they were permissive to infection by t. annulata but only to a limited extent by t. parva. further experiments involved several purified subpopulations of bovine cells including bovine monocytes, t cells and mhc class ii positive and negative populations. these subpopulations were incubated with t. annulata or t. ...19892516673
in vitro proliferative and cytotoxic responses of pbl from theileria annulata-immune cattle.peripheral blood lymphocytes were isolated from healthy calves and were subsequently infected with sporozoites of theileria annulata in vitro. the infected cells were passaged for 50 times and thereafter inoculated into animals from which they were previously isolated. within 4-5 days, schizont-containing cells were demonstrable in the lymph nodes of all animals. few days later, merozoites were detected in erythrocytes. a slight decrease in the counts of lymphocytes and leucocytes was also found ...19892596199
effect of treatment of chronic theileriosis with buparvaquone on milk yields.chronic, undulating theileria annulata infection was diagnosed as the cause of severely depressed milk yields in a herd of 44 friesian cows in egypt. the herd was divided at random into two groups of 22; one group was injected intramuscularly with a single dose of the experimental antitheilerial drug, buparvaquone, while the other remained untreated. over the subsequent seven weeks milk yield in the treated group increased to double that of the untreated group (p less than 0.05). pyrexia was con ...19892617675
theileria annulata and t. parva infect and transform different bovine mononuclear cells.bovine peripheral blood mononuclear cells (pbmc) were labelled with monoclonal antibodies recognizing bovine mhc class ii, sigm, monocyte, t-helper and t-cytotoxic cell phenotypes. they were sorted into positive and negative populations with a fluorescence-activated cell sorter (facs). the cell populations were infected in vitro with sporozoites of either theileria annulata or t. parva, and the degree of infection and transformation determined. the results showed that despite the many similariti ...19892784413
the intermediate-affinity interleukin (il)2 receptor expressed on theileria annulata-infected cells comprises a single il 2-binding protein. partial characterization of bovine il2 receptors.bovine high-, intermediate- and low-affinity interleukin 2 receptors (il2r) were studied by ligand binding and affinity labeling using 125i-labeled il2 and homobifunctional chemical cross-linking reagents. high- (kd = 17 pm) and low-affinity (kd greater than 6 nm) il 2r were detected on concanavalin a-activated peripheral blood lymphocytes (pbl). theileria annulata (ta)-infected autonomously growing pbl (ta-pbl) express predominantly intermediate-affinity il2r (kd = 1 nm). affinity-labeling stud ...19892788094
prophylactic efficacy of buparvaquone in experimentally induced theileria annulata infection in calves.the antitheilerial activity of buparvaquone (bw 720c) was evaluated in experimentally induced theileria annulata infections in cross-bred male calves. t. annulata infections were induced by injecting a suspension of infected ground tick tissue suspension (gutts) equivalent to two ticks subcutaneously into each calf. buparvaquone at a dose of 2.5 mg kg-1 body weight was given as a single injection (intramuscularly) on day 0 (group 1), day 8 (group 2) and day 12 (group 3) post-infection. the anima ...19892815531
effects of halofuginone lactate on lymphocytes and mdbk cells infected with theileria annulata and/or vesicular stomatitis virus (vsv): an in vitro study.cultures of cattle lymphocytes (lymphoblasts) infected up to 90% with theileria annulata schizonts and cultures of madin darby bovine kidney cells of cattle (mdbk) noninfected or infected with vesicular stomatitis virus (vsv) were exposed to different concentrations (50, 100, or 500 micrograms/ml) of halofuginone lactate in rpmi and mem medium, respectively. it was found that a concentration of 50 micrograms/ml halofuginone was sufficient to destroy theileria-infected as well as double-infected ...19882842746
the effects of drugs on the formation of theileria annulata merozoites in vitro.the effects of colchicine, taxol, dinitrophenol, sodium azide, tla-144, and obioactin on theileria annulata schizonts were tested in vitro and studied by means of light and electron microscopy. colchicine (0.001-5 microm) and taxol (1 microm) completely inhibited the mitosis of the host cell. this resulted in higher numbers of schizont nuclei after 96 h, since the division of the parasites was apparently not affected. increasing numbers of schizont nuclei were also obtained after incubation of p ...19882898778
bovine alloreactive cytotoxic cells generated in vitro detect bola w6 subgroups.alloreactive cytotoxic t cells (ctl) were generated in mixed lymphocyte culture against cells bearing subgroups of bola w6, as well as in bola w4, w10 and w16. primary cultures were restimulated at weekly intervals with irradiated stimulator cells and tested in a 51cr-release assay with target cells derived from theileria annulata-infected cell lines. generation of ctl was accelerated in animals that had been previously primed in vivo by skin grafting. ctl were generated that were specific for b ...19872953675
metabolic energy pathways in theileria annulata sporozoites and their significance in sporozoite-bovine lymphocyte interactions in vitro.the existence of metabolic energy pathways has been studied in extracellular t. annulata sporozoites using chemicals known to inhibit specific energy-generating pathways, and their role during invasion of bovine peripheral blood lymphocytes (pbl) by the sporozoites determined in an in vitro system. an inverse relationship was depicted between the dose of various chemicals and the number of t. annulata sporozoites invading pbl: as the concentrations of the inhibitor drugs increased, the number of ...19852986342
changes in blood chemical components during experimentally induced theileria annulata infections in cattle.during the course of infection of calves with theileria annulata levels of glucose, calcium, proteins, phosphorus, magnesium and potassium decreased and those of bilirubin, cholesterol and alkaline phosphatase increased with no changes in sodium and acid phosphatase levels. several of these biochemical alterations have been explained in relation to the injury to the liver and other organs.19863016972
stage-specific antigenicity in theileria annulata: a case report.blood from sick cattle in bahrain transmitted piroplasms of theileria annulata to a splenectomized calf. larvae of hyalomma anatolicum anatolicum were infected on the calf and, after moulting, induced clinical theileriosis, associated with numerous schizonts, in the same calf. the animal was cured by specific treatment. antigenic differences thus shown between piroplasms on the one hand, and sporozoites and schizonts on the other hand, were confirmed in the indirect fluorescent antibody test, as ...19863083573
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