Publications

theileria parva infection in calves causes massive lymphocyte death in the thymus, spleen and lymph nodes without initial proliferation.	in a study of trends and magnitudes of lymphocytes proliferation, destruction or apoptosis eleven 3-month-old healthy calves were experimentally infected with the protozoan parasite theileria parva, which is reported to cause lymphocyte proliferation. four control calves were not infected. infected and non-infected calves were sacrificed on days 9, 12, 16, 19, 23, 24 and 25 to examine lymphoid tissue changes and lymphocyte proliferation, apoptosis or necrosis in the thymus, spleen and lymph node ...	2006	16962242
large-scale intron conservation and order-of-magnitude variation in intron loss/gain rates in apicomplexan evolution.	the age of modern introns and the evolutionary forces controlling intron loss and gain remain matters of much debate. in the case of the apicomplexan malaria parasite plasmodium falciparum, previous studies have shown that while the positions of two thirds of p. falciparum introns are not shared with surveyed non-apicomplexans (leaving open the possibility that they were relatively recently gained), 99.1% are shared with plasmodium yoelii, which diverged from p. falciparum at least 100 mya. we s ...	2006	16963708
extensive genotypic diversity in a recombining population of the apicomplexan parasite theileria parva.	we evaluated sexual recombination in the apicomplexan parasite theileria parva using genome-wide marker analysis of haploid sporozoite populations obtained from infected rhipicephalus appendiculatus ticks. analysis of 231 parasite clones derived by in vitro infection of bovine lymphocytes revealed 48 distinct combinations of 64 polymorphic marker loci. one genotype accounted for more than 75% of the clones, and the population was highly inbred with respect to this. the occurrence of frequent rec ...	2006	16988220
theileria parva candidate vaccine antigens recognized by immune bovine cytotoxic t lymphocytes.	east coast fever, caused by the tick-borne intracellular apicomplexan parasite theileria parva, is a highly fatal lymphoproliferative disease of cattle. the pathogenic schizont-induced lymphocyte transformation is a unique cancer-like condition that is reversible with parasite removal. schizont-infected cell-directed cd8(+) cytotoxic t lymphocytes (ctl) constitute the dominant protective bovine immune response after a single exposure to infection. however, the schizont antigens targeted by t. pa ...	2006	16492763
notch is constitutively active in theileria-transformed b cells and can be further stimulated by the filarial nematode-secreted product, es-62.	theileria parva-infected b cells express jagged-1 and activate notch signalling in a parasite-dependent manner. es-62, a filarial nematode-secreted phosphorylcholine-containing glycoprotein, is able to further stimulate notch-mediated signalling in parasitized cells. notch is also activated to a similar extent by addition of exogenous il-10, and this occurs prior to any increase in proliferation in t. parva-infected b cells.	2006	16524753
apicomplexa genes involved in the host cell invasion: the cpa135 protein family.	the availability of a bulk of genomic data of apicomplexa parasites is a unique opportunity to identify groups of related proteins that are characteristic of this phylum. the cpa135 protein of cryptosporidium parvum is expressed and secreted through the apical complex at the invasive stage of sporozoite. this protein is characterised by an lccl domain, a common trait of various secreted proteins within apicomplexa. using the cpa135 as a "virtual template", we have identified cpa135 orthologous g ...	2006	16881408
molecular characterization of a theileria lestoquardi gene encoding for immunogenic protein splice variants.	a theileria lestoquardi schizont cdna library was screened using sera collected from sheep recovering from a natural malignant theileriosis infection. an immunogenic clone (clone-5) was isolated and its full sequence was obtained using rapid amplification of cdna ends polymerase chain reaction (pcr) technique. pcr experiments and sequencing demonstrated the presence of two transcript forms of the gene, resulting from splicing variation at the single intron found in the gene. both gene products, ...	2006	16896652
factors influencing the distribution of questing ticks and the prevalence estimation of t. parva infection in brown ear ticks in the tanga region, tanzania.	questing ticks from various districts and agro-ecological zones (aez) in the tanga region of tanzania were studied for a two-year period between september 1999 and july 2001. collections of both nymphal and adult ticks occurred at 29 sites using a blanket or white cloth dragging technique. the species recorded in the order of decreasing abundance were rhipicephalus appendiculatus, boophilus spp., and ambylomma variegatum. rhipicephalus appendiculatus field infestation levels varied across admini ...	2006	17249338
use of micro-rotation imaging to study jnk-mediated cell survival in theileria parva-infected b-lymphocytes.	lymphocytes infected with the protozoan parasite theileria parva are transformed to permanently proliferating cells, an event underlying the pathology of the disease. however, the molecular signalling mediating this process is complex and poorly understood. here, we show that down-regulation of jnk signalling by transient over expression of a dominant-negative mutant of jnk (jnk-apf) significantly increases annexin-v-phycoerythrin (v-pe) labelling on infected b cell populations observed using fl ...	2005	15977899
detection of a novel parasite kinase activity at the toxoplasma gondii parasitophorous vacuole membrane capable of phosphorylating host ikappabalpha.	toxoplasma gondii activates the nf-kappab pathway in the infected host cell resulting in upregulation of pro-survival genes and prevention of apoptosis. manipulation of the nf-kappab cascade by t. gondii correlates with the localization of phosphorylated ikappab at the parasitophorous vacuole membrane (pvm). this suggests a parasite-mediated event, involving the recruitment and activation of the host ikappab kinase (ikk) complex, as has been observed with the related protozoan theileria parva. i ...	2005	15679838
theileria parva seroprevalence in traditionally kept cattle in southern zambia and el nino.	sero-epidemiological surveys involving 27,526 cattle over a period of 8 years show that theileria parva, the parasite causing east coast fever (ecf) is found throughout southern zambia. higher values of t. parva sero-prevalence were observed in the plateau districts of monze, choma and mazabuka than in the valley districts of siavonga and sinazongwe. our results reveal a strong association between high t. parva sero-prevalence and the presence of the periodic climatic phenomenon known as the el ...	2005	15777915
novel baculovirus-derived p67 subunit vaccines efficacious against east coast fever in cattle.	two novel baculovirus-derived recombinant theileria parva p67 constructs were tested for their vaccine potential against east coast fever. boran calves were immunized with a his-gfp-p67 fusion protein (gfp:p67deltass) or with gp64:p67c, a protein fusion between a c-terminal domain of p67 and the baculovirus envelope protein gp64. both gfp:p67deltass and gp64:p67c induced antibodies with high elisa titers that neutralized t. parva sporozoites with high efficiency. upon challenge, a correlation wa ...	2005	15780727
population genetic analysis and sub-structuring of theileria parva in uganda.	in recent years the population structures of many apicomplexan parasites including plasmodium spp., toxoplasma gondii and cryptospordium parvum have been elucidated. these species show a considerable diversity of population structure suggesting different strategies for transmission and survival in mammalian hosts. we have undertaken a population genetic analysis of another apicomplexan species (theileria parva) to investigate the levels of diversity of this parasite and the role of genetic excha ...	2005	15760662
subunit vaccine based on the p67 major surface protein of theileria parva sporozoites reduces severity of infection derived from field tick challenge.	two recombinant vaccines against theileriaparva, based on a near full-length version of the sporozoite surface antigen p67 (p67(635)), or an 80 amino acid c-terminal section (p67c), were evaluated by exposure of immunized cattle to natural tick challenge in two sites at the kenya coast and one in central kenya. vaccination reduced severe ecf by 47% at the coast and by 52% in central kenya from an average incidence of 0.53+/-0.07 (s.e.) in 50 non-immunised controls to an average of 0.27+/-0.05 in ...	2005	15811656
genetics. themes and variations in apicomplexan parasite biology.		2005	15994520
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 ...	2005	15994557
genome sequence of theileria parva, a bovine pathogen that transforms lymphocytes.	we report the genome sequence of theileria parva, an apicomplexan pathogen causing economic losses to smallholder farmers in africa. the parasite chromosomes exhibit limited conservation of gene synteny with plasmodium falciparum, and its plastid-like genome represents the first example where all apicoplast genes are encoded on one dna strand. we tentatively identify proteins that facilitate parasite segregation during host cell cytokinesis and contribute to persistent infection of transformed h ...	2005	15994558
spatial and management factors associated with exposure of smallholder dairy cattle in tanzania to tick-borne pathogens.	a cross-sectional study of serum antibody responses of cattle to tick-borne pathogens (theileria parva, theileria mutans,anaplasma marginale, babesia bigemina and babesia bovis) was conducted on smallholder dairy farms in tanga and iringa regions of tanzania. seroprevalence was highest for t. parva (48% in iringa and 23% in tanga) and b. bigemina (43% in iringa and 27% in tanga) and lowest for b. bovis (12% in iringa and 6% in tanga). we use spatial and non-spatial models, fitted using classical ...	2005	16023121
comparison of manual and homogenizer methods for preparation of tick-derived stabilates of theileria parva: equivalence testing using an in vitro titration model.	theileria parva sporozoite stabilates are used in the infection and treatment method of immunization, a widely accepted control option for east coast fever in cattle. t. parva sporozoites are extracted from infected adult rhipicephalus appendiculatus ticks either manually, using a pestle and a mortar, or by use of an electric homogenizer. a comparison of the two methods as a function of stabilate infectivity has never been documented. this study was designed to provide a quantitative comparison ...	2005	16038395
analysis of the transcriptome of the protozoan theileria parva using mpss reveals that the majority of genes are transcriptionally active in the schizont stage.	massively parallel signature sequencing (mpss) was used to analyze the transcriptome of the intracellular protozoan theileria parva. in total 1,095,000, 20 bp sequences representing 4371 different signatures were generated from t.parva schizonts. reproducible signatures were identified within 73% of potentially detectable predicted genes and 83% had signatures in at least one mpss cycle. a predicted leader peptide was detected on 405 expressed genes. the quantitative range of signatures was 4-52 ...	2005	16186131
a longitudinal study of sero-conversion to tick-borne pathogens in smallholder dairy youngstock in tanzania.	a longitudinal study of sero-conversion of youngstock to the tick-borne pathogens theileria parva, t. mutans, anaplasma marginale, babesia bigemina and b. bovis was conducted over two years on smallholder dairy farms in tanga region, tanzania. there was evidence of maternal antibodies to all tick-borne pathogens in animals less than 18 weeks of age. seroprevalence increased as expected with age in animals older than this but seroprevalence profiles underestimated the force of infection due to wa ...	2005	15936149
taking the myc is bad for theileria.	it is commonly acknowledged that intracellular parasites manipulate the survival pathways of the host cells to their own ends. theileria are masters of this because they invade bovine leukocytes and immortalize them. host-cell survival depends on the presence of live parasites, and parasite death results in the leukocyte undergoing programmed cell death. the parasite, therefore, activates several anti-apoptotic pathways in host cells to ensure its own survival. in b cells that are infected by th ...	2005	15979941
prevalence of theileriosis in red hartebeest (alcelaphus buselaphus caama) in namibia.	a total of 23 blood samples from red hartebeest and 28 ticks of the subspecies rhipicephalus evertsi were collected in namibia during the summer 2003. for a piroplasmida species, theileria sp 95.7% of blood and 50.0% of tick samples (all r. e. mimeticus, none of r. e. evertsi were carrying the pathogen) were pcr positive. sequencing showed infection from a re-emerging mild species of theileria phylogenetically different from other african theileria species such as theileria parva, t. buffeli, t. ...	2005	15986252
some preliminary observations on the susceptibility and resistance of different cattle breeds to theileria parva infection.	theileria parva-naïve friesian (bos taurus), boran (bos indicus) and maasai zebu steers (b. indicus) were infected with a t. parva sporozoite stabilate dose which had previously been shown to induce an estimated 50% mortality rate in boran cattle. all the cattle developed patent infections with no significant differences in the length of the prepatent period to development of macroschizonts (p > 0.05) between the three groups. clinical theileriosis occurred in all eight the friesians (100%), fiv ...	2005	15991701
in vivo comparison of susceptibility between bos indicus and bos taurus cattle types to theileria parva infection.	the objective of this study was to determine whether bos taurus cattle differ form bos indicus in their susceptibility to infection with the muguga stabilate of theileria parva and in their resistance to the resultant disease. ten friesians (b. taurus), ten improved borans (b. indicus), ten unimproved borans (b. indicus) and ten zebus (b. indicus) born to dams from an east coast fever (ecf) endemic area were inoculated with an infective dose50 dilution of t. parva muguga stabilate 147. all the a ...	2005	15991702
reverse line blotting: a new technique for the sensitive detection of tick borne pathogens.	recently, a new molecular diagnostic technique for tick borne pathogens has been developed and is called reverse line blotting. this paper outlines the basis of this method and then illustrates its use for the analysis of blood samples obtained from ugandan cattle and buffalo. the sensitivity and the specificity are discussed in relation to the use of this technique in the maghreb	2004	16929766
an unusual mosaic structure of the pim gene of theileria parva and its relationship to allelic diversity.	genetic diversity and structural organisation of the polymorphic immunodominant molecule (pim) gene of the protozoan parasite theileria parva was studied in isolates from sympatric and allopatric areas. the analyses revealed a mosaic structure consisting of highly conserved regions shared among some of the isolates from geographically different areas and homologous sequence runs shared among isolates from one area. the specific pattern of diversity in which large insertions and deletions were ob ...	2004	14698429
treatment of east coast fever of cattle with a combination of parvaquone and frusemide.	pulmonary oedema is a common sign of east coast fever (ecf, theileria parva infection) of cattle. a trial was conducted on farms in uganda to compare a product containing both the antitheilerial compound parvaquone and the diuretic compound frusemide with one containing only parvaquone, in the treatment of ecf. the trial involved 40 clinical cases of ecf, some of them complicated by other infections, in cattle of all ages and on several farms. confirmed cases were treated with either parvaquone+ ...	2004	15080540
application of a reverse line blot assay to the study of haemoparasites in cattle in uganda.	recent advances in genomic technology have focused many veterinary researchers on the possibility of producing one multivalent recombinant vaccine against all the haemoparasites that infect cattle in the tropics. before such a vaccine is developed it is essential to define target cattle populations as well as the range of anti-pathogen vaccines required in order to control disease. to further this objective, we have evaluated a reverse line blot (rlb) assay, which simultaneously detects the prin ...	2004	15064125
bovine leukocyte antigen major histocompatibility complex class ii drb32703 and drb31501 alleles are associated with variation in levels of protection against theileria parva challenge following immunization with the sporozoite p67 antigen.	initial laboratory trials of an experimental subunit vaccine against theileria parva based on the 67-kda major sporozoite surface antigen revealed a range of responses to challenge. we have analyzed convergence in seven sets of monozygotic twins which suggests that genetic factors may have an influence in determining the degree of protection provided by p67 immunization. in addition, we have examined whether allelic diversity at major histocompatibility complex class ii loci influences protectio ...	2004	15102783
variation in body size in the tick complex rhipicephalus appendiculatus/rhipicephalus zambeziensis.	we examined the relationship between body size and the phenology of the tick complex rhipicephalus appendiculatus/rhipicephalus zambeziensis. these ticks transmit theileria parva in cattle. in africa, the body size of r. appendiculatus increases with latitude while the body size of the morphologically similar rhipicephalus zambeziensis is constant at two different latitudes. a larger body size is necessary once survival becomes a constraint. the most plausible explanation for the smaller r. appe ...	2004	15707294
evaluation of the indirect fluorescent antibody test as a diagnostic tool for east coast fever in eastern zambia.	serological surveys using the schizont indirect fluorescence antibody test (ifat) are routinely carried out to monitor the theileria parva infection prevalence. the present study evaluates the diagnostic accuracy of the ifat in eastern zambia, where the transmission of t. parva is highly seasonal. the data set resulted from a sentinel herd (n = 105 animals) study carried out between 1995 and 2000 and was split into an epidemic period, during which the majority of the cattle became infected, and ...	2004	15710519
improved immunogenicity of novel baculovirus-derived theileria parva p67 subunit antigens.	east coast fever (ecf) in cattle is caused by the tick-borne protozoan parasite theileria parva. the major sporozoite surface antigen of t. parva (p67) is an important candidate for inclusion in a subunit vaccine. recently, we reported the expression and production of different parts of p67 as fusions to either gfp or to the baculovirus gp64 envelope glycoprotein in insect cells, which resulted in stable proteins recognized by a monoclonal specific for native p67. the immunogenicity of these fus ...	2004	15110403
a membrane-anchored theileria parva cyclophilin with a non-cleaved amino-terminal signal peptide for entry into the endoplasmic reticulum.	recent studies suggest that peptidyl-prolyl isomerases of the cyclophilin family, that access the secretory pathway, can be involved in the interaction of parasitic protozoa with mammalian host cells. the amino acid sequence of a cdna encoding a cyclophilin family member of the intracellular protozoan parasite of cattle theileria parva contains a conserved c-terminal domain that exhibits 70% amino acid identity to cyclophilin proteins from other organisms, and a unique 60 amino acid novel n-term ...	2004	15110404
an amino acid substitution in the babesia bovis dihydrofolate reductase-thymidylate synthase gene is correlated to cross-resistance against pyrimethamine and wr99210.	the genomic locus and cdna encoding babesia bovis dihydrofolate reductase-thymidylate synthase (dhfr-ts) were cloned and sequenced. a single dhfr-ts gene, composed of four exons, encodes a 511 aa protein that is most closely related to plasmodium falciparum dhfr-ts. the genomic locus is characterized by the presence of four other genes of which at least three are expressed during the erythrocytic cycle. three of the genes were highly conserved in closely related theileria species and for two of ...	2004	14698433
in vitro titration of theileria parva tick derived stabilates.	immunization against the protozoan theileria parva by infection and treatment has proved to be very efficient for the control of east coast fever, an acute and often-fatal lymphoproliferative tick-borne disease of cattle in eastern, central and southern africa. the immunizing dose of live t. parva sporozoites used in this method is usually determined by in vivo titration. an alternative in vitro method of quantification of sporozoites in whole tick-derived stabilates is proposed. the method cons ...	2004	15030000
comparative studies on the infectivity of theileria parva in ticks fed in vitro and those fed on cattle.	nymphs of the brown ear tick, rhipicephalus appendiculatus, were fed on heparinised bovine blood infected with theileria parva parasites in an in vitro feeding system consisting of rabbit skin membranes. the main feeding and development parameters such as the mean attachment rate, feeding duration and engorgement weights of membrane-fed ticks were not significantly different from nymphs fed on cattle. the moulting rate was also comparable although a slight significant difference was observed. as ...	2004	15139272
endemic stability for theileria parva infections in ankole calves of the ankole ranching scheme, uganda.	a population-based study was carried out on the ankole ranching scheme in south-west uganda with the aim of determining the endemic status of theileria parva infections. for this purpose, the age-related sero-prevalence of t. parva and the specific calf mortality associated with the parasite were assessed. blood samples were collected from 931 ankole calves of up to 12 months of age from 81 randomly selected herds. the relationship between rainfall pattern and whole-body rhipicephalus appendicul ...	2004	15580767
characterisation of theileria parva isolates from kiambu district, kenya.	four theileria parva isolates from muguga area of kiambu district, kenya, were used to establish schizont-infected cell lines. their protein antigens were then separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (sds page). the isolates were subsequently subjected to protein analysis and characterisation by the western immunoblotting technique. probing for the polymorphic immunodominant molecule (pim) was done using monoclonal antibody no. 4. sds page detected up to 20 protei ...	2004	15135864
the effect of dexamethasone and promethazine in combination with buparvaquone in the management of east coast fever.	the effects of dexamethasone and promethazine on the amelioration of pulmonary oedema in east coast fever were investigated. the clinical effects of these drugs were further investigated when used in conjunction with the antitheilerial drug, buparvaquone. in the first experiment, 15 crossbred (friesian x zebu) steers were divided into four groups. with the exception of the animals in group iv, that served as a control group all the others were infected with theileria parva sporozoites. on the se ...	2004	15373334
identification of a piroplasm protein of theileria orientalis that binds to bovine erythrocyte band 3.	theileria orientalis infects cattle and causes various disease symptoms, including anaemia and icterus. the erythrocytic stages are responsible for these symptoms but the molecular events involved in these stages have not yet been fully elucidated. in this study, we identified a t. orientalis cdna that encodes a polypeptide related to identity to the microneme-rhoptry protein of theileria parva. analysis of its recombinant product (tomrp) by indirect fluorescent-antibody test revealed that it is ...	2004	15383289
genes transcribed in the salivary glands of female rhipicephalus appendiculatus ticks infected with theileria parva.	we describe the generation of an auto-annotated index of genes that are expressed in the salivary glands of four-day fed female adult rhipicephalus appendiculatus ticks. a total of 9162 est sequences were derived from an uninfected tick cdna library and 9844 ests were from a cdna library from ticks infected with theileria parva, which develop in type iii salivary gland acini. there were no major differences between abundantly expressed ests from the two cdna libraries, although there was evidenc ...	2004	15475305
theileria parva: in vitro studies on the effects of holding temperature, ph and medium on sporozoite infectivity.	the effects of holding temperature, ph and medium on the infectivity of theileria parva sporozoites were investigated using an in vitro infectivity assay. the sporozoite infectivity lasted for 72 h at a holding temperature of 4 c but for only 24 h at 24 degrees c. sporozoite infectivity was found to be sensitive to ph variations and sporozoites were most infective between ph 7 and ph 8. there was a significant loss in infectivity at ph 5 and infectivity was almost totally abolished at ph 9. thei ...	2004	15241968
the persistence of component theileria parva stocks in cattle immunized with the 'muguga cocktail' live vaccine against east coast fever in uganda.	the 'muguga cocktail' live vaccine comprises three theileria parva stocks (muguga, kiambu 5 and the buffalo-derived serengeti-transformed) and has been used extensively in eastern, central and southern africa with an infection and treatment protocol to protect cattle against east coast fever. we report the characterization of the three component vaccine stocks using a panel of polymorphic micro-satellite and mini-satellite markers and the development of a stock-derived pcr method that distinguis ...	2004	15267109
the prevalence of serum antibodies to tick-borne infections in mbale district, uganda: the effect of agro-ecological zone, grazing management and age of cattle.	between august and october 2000, a cross-sectional study was conducted in smallholder dairy farms in mbale district, uganda to assess the prevalence of ticks and tick-borne diseases under different grazing systems and agro-ecological zones and understand the circumstances under which farmers operated. a questionnaire was administered to obtain information on dairy farm circumstances and practices. a total of 102 farms were visited and sera and ticks were collected from 478 animals. sero-prevalen ...	2004	15861224
development of a chitinase and v-cathepsin negative bacmid for improved integrity of secreted recombinant proteins.	the application of the baculovirus-insect cell expression system for the production of integral membrane and secreted proteins is often more troublesome than for cytoplasmic proteins. one protein expressed at low levels in insect cells is the theileria parva sporozoite surface protein p67. theileria parva is a protozoan parasite, which causes the tick-transmitted disease east coast fever in cattle. baculovirus vectors were engineered to produce a secreted form of p67 by replacing the signal pept ...	2004	15488628
merogony in in vitro cultures of theileria parva.	in vitro studies were focussed on the duration and cessation of merogony in theileria parva infected blood lymphocyte cell cultures. the cultures were infected using purified tick stabilates as an alternative to in vitro infections, using sporozoites obtained by labour intensive dissections of salivary glands from infected ticks. after establishment of infection in peripheral blood lymphocytes (pbl), merozoites were temporarily produced for about 2 months after which lymphoblasts only contained ...	2003	12788254
a tumour necrosis factor alpha autocrine loop contributes to proliferation and nuclear factor-kappab activation of theileria parva-transformed b cells.	theileria infection of bovine leucocytes induces uncontrolled proliferation and a transformed phenotype comparable to tumour cells. infected cells have many characteristics of activated leucocytes and use autocrine loops to augment proliferation. we have shown previously that, in infected b cells, pi3-k controls a granulocyte-macrophage colony-stimulating factor (gm-csf) autocrine loop to increase both proliferation and activation of the activator protein 1 (ap-1) transcription factor. we show h ...	2003	12969376
survival of theileria parva-infected adult rhipicephalus appendiculatus under laboratory and quasi-natural conditions.	adult rhipicephalus appendiculatus muguga, having high or low intensities of theileria parva muguga infection in their salivary glands, were exposed to 20 degrees c and 85% relative humidity in the laboratory or quasi-natural conditions. survival of the ticks and t. parva infections in their salivary glands was then monitored over a two year period. ticks, having an average infection level of 2 infected acini per female, survived for up to 70 or 106 weeks after moulting under the laboratory or q ...	2003	14635820
constitutive exclusion of csk from hck-positive membrane microdomains permits src kinase-dependent proliferation of theileria-transformed b lymphocytes.	infection of bovine t cells and b cells with the intracellular protozoan parasite theileria parva induces a transformed phenotype with characteristics comparable to leukemic cells. the transformed phenotype reverts on drug-induced parasite death, and the cured lymphocytes acquire a resting phenotype and eventually die by apoptosis if not further stimulated. here, we show that both lymphocyte proliferation and activation of the transcription factor ap-1 are mediated by src-family protein tyrosine ...	2003	12411311
survival of theileria parva in its nymphal tick vector, rhipicephalus appendiculatus, under laboratory and quasi natural conditions.	groups of nymphal rhipicephalus appendiculatus muguga, having a mean of 1 or 9 theileria parva muguga-infected salivary gland acini per tick, were kept under quasi-natural conditions at an altitude of 1950 m or 20 degrees c at a relative humidity of 85% in the laboratory and their survival and infection prevalence and abundance determined over time. theileria parva infections for both categories of ticks survived in the nymphal ticks for 50 or 26 weeks post salivary gland infection under quasi-n ...	2003	12866795
theileria parva-transformed t cells show enhanced resistance to fas/fas ligand-induced apoptosis.	lymphocyte homeostasis is regulated by mechanisms that control lymphocyte proliferation and apoptosis. activation-induced cell death is mediated by the expression of death ligands and receptors, which, when triggered, activate an apoptotic cascade. bovine t cells transformed by the intracellular parasite theileria parva proliferate in an uncontrolled manner and undergo clonal expansion. they constitutively express the death receptor fas and its ligand, fasl but do not undergo apoptosis. upon eli ...	2003	12874209
immunity to east coast fever in cattle induced by a polypeptide fragment of the major surface coat protein of theileria parva sporozoites.	full-length recombinant versions of p67, the 709 amino acid major surface protein of theileria parva sporozoites, induce immunity to east coast fever (ecf) in cattle. we show that a soluble escherichia coli recombinant version of p67 (p67(635)), in which a prokaryotic signal peptide replaces the eukaryotic one, confers protection comparable to that induced by the full-length molecule, but is unstable. peptides encoding 80 (p67c) and 205 (p67n) amino acid fragments of p67, containing epitopes rec ...	2003	12559799
baculovirus surface display of theileria parva p67 antigen preserves the conformation of sporozoite-neutralizing epitopes.	theileria parva is an intracellular protozoan parasite that causes east coast fever, a severe lymphoproliferative disease in cattle. previous attempts to produce recombinant sporozoite surface antigen (p67) in bacterial or insect cells for vaccine purposes have not resulted in a correctly folded protein. here, we report the expression of n- and c-terminal domains of p67 fused to the baculovirus envelope glycoprotein gp64 by cloning the appropriate p67 cdna segments between the signal sequence an ...	2003	12646695
apoptosis of theileria-infected lymphocytes induced upon parasite death involves activation of caspases 9 and 3.	the intracellular parasite theileria parva (t. parva) can infect bovine b and t-lymphocytes. t. parva-infected cells become transformed, and they survive and proliferate independently of exogenous growth factors. in vivo the uncontrolled cellular proliferation associated with lymphocyte transformation underlies the pathogenesis of the disease called east coast fever. the transformed state of parasitised cells can be reversed upon elimination of the parasite by specific theilericide drugs. in thi ...	2003	14585544
cell invasion by theileria sporozoites.		2003	12488213
evaluation of pcr to detect theileria parva in field-collected tick and bovine samples in tanzania.	the ability of pcr to detect infections of theileria parva, the cause of east coast fever, in field-collected tick and bovine samples from tanzania was evaluated. pcr-detected infection prevalence was high (15/20, 75%) in unfed adult rhipicephalus appendiculatus ticks that fed as nymphs on an acutely-infected calf, but low (22/836, 2.6%) in unfed adult r. appendiculatus collected from field sites in tanzania. tick infection prevalence was comparable to that in previous studies that used salivary ...	2003	12591193
theileria-induced leukocyte transformation.	the intracellular protozoan parasites theileria parva and t. annulata transform the cells they infect, inducing uncontrolled proliferation. this is not a trivial event as, in addition to permanently switching on the complex pathways that govern all steps of the cell cycle, the built-in apoptotic safety mechanisms that prevent 'illegitimate' cell replication also need to be inactivated. recent experiments show that the nf-kappa b and phosphoinositide 3-kinase (ptdins-3k) pathways are important pa ...	2003	12941408
lyophilisation and resuscitation of sporozoites of theileria parva: preliminary experiments.	lyophilisation of theileria parva sporozoite stabilates used for immunisation of cattle against east coast fever would greatly improve vaccine storage and delivery. we report three attempts to lyophilise and resuscitate the sporozoites of t. parva. sporozoites survived lyophilisation and were effective for immunisation. lyophilised stabilate survived for 2 weeks at 5 degrees c and for 12 weeks at -20 degrees c. although the viability of the stabilates was severely reduced during lyophilisation, ...	2003	14615148
a panel of microsatellite and minisatellite markers for the characterisation of field isolates of theileria parva.	mini- and microsatellite sequences show high levels of variation and therefore provide excellent tools for both the genotyping and population genetic analysis of parasites. herein we describe the identification of a panel of 11 polymorphic microsatellites and 49 polymorphic minisatellites of the protozoan haemoparasite theileria parva. the pcr products were run on high resolution spreadex gels on which the alleles were identified and sized. the sequences of the mini- and microsatellites were dis ...	2003	14636680
immunisation against theileria parva in eastern zambia: influence of maternal antibodies and demonstration of the carrier status.	immunisation of calves by the infection and treatment method (i & t) has been extensively used in the eastern province of zambia to control east coast fever (ecf), a protozoan tick-borne disease. this paper presents the results of a field longitudinal study, which included a total of 148 angoni calves. after immunisation against ecf, they were monitored for a full rainy season, coinciding with the main peak of activity of the vector of theileria parva, the tick rhipicephalus appendiculatus. dysi ...	2002	12446089
distribution and phenology of ixodid ticks in southern zambia.	distribution data for epidemiologically important ticks (acari: ixodidae) in the southern province of zambia, one of the main cattle areas of the country, are presented. boophilus microplus (canestrini) was not recorded in southern zambia, whereas boophilus decoloratus (koch) is present throughout the area. new distribution patterns for less economically important ixodid ticks are also discussed. southern zambia is a transition zone because it is the most northern area in africa where mixed rhip ...	2002	12510896
mp23, a theileria parva transmembrane protein with homology to the protein disulfide isomerase family.		2002	12034460
comparative studies of the efficacy of parvaquone and parvaquone-plus-frusemide in the treatment of theileria parva infection (east coast fever) in cattle.	comparative studies of the efficacy of parvaquone (parvexon) and parvaquone-plus-frusemide (fruvexon) bimeda chemicals, ireland, were done on 60 naturally infected cases of east coast fever (ecf; theileria parva infection in cattle). small-scale dairy farmers in the peri-urban of dar es salaam city reported ecf-suspected cases from march to mid-october 2001 and were treated with the two drugs alternately, as were diagnosed positive for ecf. four sub-groups of 15 cattle each (early stage, 15; adv ...	2002	12237138
buffalo-associated theileria parva: the risk to cattle of buffalo translocation into the highveld of zimbabwe.	there has been an increase in the introduction of game animals, including african buffaloes, into the highveld of zimbabwe to establish private game reserves on condition that they are confined in separate and secured paddocks. owing to shortages of pastures cattle were grazed in buffalo-grazed paddocks resulting in outbreaks of buffalo-derived theileriosis. this paper reports the results of epidemiological observations carried out on two game reserves to assess the risk of buffalo translocation ...	2002	12381605
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 ...	2002	11897130
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 ...	2002	11812618
theileria parva epidemics: a case study in eastern zambia.	this paper presents the results of the follow-up of three sentinel herds between 1994 and 2000 during an east coast fever (ecf) epidemic in eastern zambia. the animals of the sentinel herds were closely monitored clinically and serologically together with detailed rhipicephalus appendiculatus counts. peaks of disease incidence occurred in the rainy season (december-february) and the dry months of may-july with nymph-to-adult tick transmission dominating the infection dynamics. a second wave of a ...	2002	12072213
fusion to green fluorescent protein improves expression levels of theileria parva sporozoite surface antigen p67 in insect cells.	east coast fever (ecf) is a fatal disease of cattle caused by the protozoan parasite theileria parva. the development of a subunit vaccine, based on the sporozoite-specific surface antigen p67, has been hampered by difficulties in achieving high-level expression of recombinant p67 in a near-authentic form. therefore two sets of recombinant baculovirus vectors were constructed. the first set, encoding various regions of p67, produced low levels of the corresponding p67 domains in high five cells, ...	2002	12553568
the persistence of theileria parva infection in cattle immunized using two stocks which differ in their ability to induce a carrier state: analysis using a novel blood spot pcr assay.	an improved theileria parva dna detection assay based on the polymerase chain reaction (pcr) using primers derived from the 104 kda antigen (p104) gene was developed to detect parasite dna in blood spots on filter paper. the specificity of the assay was validated using dna from a wide range of cattle-derived and buffalo-derived stocks of t. parva. dna of t. annulata, t. buffeli, t. lestoquardi, t. mutans and t. taurotragi was not amplified using the p104 primers. the detection threshold of the a ...	2002	11922428
using glimmerm to find genes in eukaryotic genomes.	glimmerm is a eukaryotic gene finder that has been used in the annotation of the genomes of plasmodium falciparum (the malaria parasite), the model plant arabidopsis thaliana, oryza sativa (rice), the parasite theileria parva, and the fungus aspergillus fumigatus. a unique feature of the system compared to other eukaryotic gene finders is a module that allows users to provide their own data and train glimmerm for any organism.	2002	18792941
immunization of cattle against east coast fever using theileria parva (marikebuni) and relaxation of tick control in north rift, kenya.	a total of 90 animals was immunized against east coast fever (ecf) using theileria parva (marikebuni) stock on three large-scale farms in kiminini division, trans-nzoia district, north rift, kenya. another 90 cattle served as non-immunized controls. following immunization the number of cattle with significant indirect fluorescent antibody (ifa) titres increased from 43.9% to 84.4% and 6.7% of the cattle developed clinical ecf reactions. two months after immunization, the immunized and non-immuni ...	2001	11769354
laboratory and field investigations into the theileria parva carrier-state in cattle in zimbabwe.	the theileria parva carrier-state in cattle on commercial farms on zimbabwe was investigated using parasitological and serological methods. the proportion of cattle showing theileria piroplasms on two farms, which had recent histories of disease outbreaks, were 64% (n = 106, total of heifers and weaned calves examined) and 71.5% (n = 60) while the proportion of t. parva antibodies for the same animals were 59% and 98.5%, respectively. on four farms where no cases of the disease occurred for over ...	2001	11769352
tick-theileria interactions in response to immune activation of the vector.	watt, d. m., walker, a. r., lamza, k. a., and ambrose, n. c. 2001. tick-theileria interactions in response to immune activation of the vector. experimental parasitology 97, 89-94. immune mechanisms towards the haemoprotozoan parasite theileria parva were investigated in their tick vector, rhipicephalus appendiculatus. the exoskeletons of adult ticks were initially pierced with bacteria-coated, saline-coated, or sterile dry glass needles. haemolymph was extracted from the ticks at 6, 24, 48, and ...	2001	11281705
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 ...	2001	11488815
the impact of theileria parva infections and other factors on calf mean daily weight gains in smallholder dairy farms in murang'a district, kenya.	the association between mean daily weight gain, theileria parva infections, clinical east coast fever and other possible determinants of weight gain were examined in a longitudinal observational study that was conducted in cohorts of female calves from five agro-ecological zone (aez)-grazing strata. the strata were upper-midlands (um) 1 zero-grazing, um 1 open-grazing, um 2 zero-grazing, um 4 zero-grazing and um 4 open-grazing. in total, 225 calves on 188 smallholder dairy farms were visited wit ...	2001	11535277
identification of a target population for immunisation against east coast fever in coastal kenya.	two experiments were carried out to identify the target population of cattle for immunisation against east coast fever (ecf) using the infection-and-treatment method. firstly, a sentinel-calf study was used to determine the age window for ecf immunisation by determining ages at clinical detection of infection with theileria parva. six groups of five naive cross-bred (bos taurus/bos indicus) male calves, introduced at intervals of 2 months at a mean age of 26 days, were exposed to natural tick ch ...	2001	11566376
differential roles of toll-like receptors in the elicitation of proinflammatory responses by macrophages.	mammalian toll-like receptor (tlr) proteins are pattern recognition receptors for a diverse array of bacterial and viral products. gram negative bacterial lipopolysaccharide (lps) activates cells through tlr4, whereas the mycobacterial cell wall glycolipids, lipoarabinomannan (lam) and mannosylated phosphatidylinositol (pim), activate cells through tlr2. furthermore, short term culture filtrates of m. tuberculosis bacilli contain a tlr2 agonist activity, termed soluble tuberculosis factor (stf), ...	2001	11890657
an epidemic of east coast fever on a dairy farm in eastern tanzania.	during the period august-september 1995, an epidemic of east coast fever occurred at a dairy farm in morogoro region of eastern tanzania. due to an intensive dipping scheme since 1970, a very unstable endemic status had been established in the animals. a breakdown in the dipping scheme caused a major disease outbreak; the dip wash was not changed for 18 months prior to the outbreak and dipping continued in a dip wash of unknown strength. there was also a delay in detecting the disease at an earl ...	2001	11267688
transmission of theileria parva in the traditional farming sector in the southern province of zambia during 1997-1998.	the incidence of first contact with the protozoan theileria parva was determined in two traditional cattle herds in the southern province of zambia during a period of average rainfall in 1997 and 1998, following a drought in the previous two years. compared to that period, there was a marked increase in the number of rainy season first contacts attributable to transmission by rhipicephalus appendiceulatus adults. however, there were still more dry season contacts that resulted from nymphal trans ...	2001	11254072
exposure of cattle immunized with different stocks of theileria parva to buffalo-associated theileria challenge on two game parks in zimbabwe.	eight cattle immunized with cattle-derived theileria parva boleni stabilate together with six susceptible controls were released in dombawera game park on the highveld of zimbabwe. this coincided with rhipicephalus appendiculatus nymphal activity. the cattle grazed together with african buffaloes (syncerus caffer) and were not treated against tick infestation. the nymphal tick infestation was high, and seven of the eight immunized cattle and three of the controls had severe and fatal reactions. ...	2001	11769351
characterisation of single domain atp-binding cassette protien homologues of theileria parva.	two distinct genes encoding single domain, atp-binding cassette transport protein homologues of theileria parva were cloned and sequenced. neither of the genes is tandemly duplicated. one gene, tpabc1, encodes a predicted protein of 593 amino acids with an n-terminal hydrophobic domain containing six potential membrane-spanning segments. a single discontinuous atp-binding element was located in the c-terminal region of tpabc1. the second gene, tpabc2, also contains a single c-terminal atp-bindin ...	2001	11570560
epidemiological observations of zimbabwean theileriosis: disease incidence and pathogenicity in susceptible cattle during rhipicephalus appendiculatus nymphal and adult seasonal activity.	fifty-nine hereford cattle susceptible to tick-borne diseases were used as tracer animals to assess the tick challenge and pathogenicity of theileria parva under field conditions in zimbabwe. they were moved periodically in groups of five to three commercial farms (one group consisted of four) during seasons of rhipicephalus appendiculatus nymphal and adult activity. all tracer cattle were herded together with the farm cattle but were not dipped. the nymphal tick counts were high on two of the f ...	2001	11769350
cellular immunity against theileria parva and its influence on parasite diversity.	theileria parva, a tick-borne parasite of african cattle, causes a fatal disease known as east coast fever. cattle that recover from the disease develop strong parasite-specific mhc-class i-restricted cytotoxic t-lymphocyte responses. protection can be transferred between immune and naïve calves in the cd8+ t cell fraction emanating from a responding lymph node. in vitro studies suggest that this response requires input from activated cd4+ t cells. the t parva life cycle involves developmental s ...	2001	11170857
comparison of cryoprotectants in the preservation of theileria parva sporozoites using an in vitro infectivity assay.	an in vitro infectivity assay was used to examine five cryoprotectants for their suitability for preserving theileria parva sporozoites. all five were capable of preserving t. parva sporozoites through freezing, the optimal concentrations being 7.5% for glycerol, 5% for dimethyl sulphoxide (dmso), poly (vinylpyrrolidone) (pvp) and poly(ethylene glycol) (peg), and 2.5% for hydroxyethyl starch (hes). when the five cryoprotectants were compared at their optimal concentrations, using a modification ...	2001	11234190
molecular and immunological characterisation of theileria parva stocks which are components of the 'muguga cocktail' used for vaccination against east coast fever in cattle.	the 'muguga cocktail' which is composed of three theileria parva stocks muguga, kiambu 5 and serengeti-transformed has been used extensively for live vaccination against east coast fever in cattle in eastern, central and southern africa. herein we describe the molecular characterisation of the t. parva vaccine stocks using three techniques, an indirect fluorescent antibody test with a panel of anti-schizont monoclonal antibodies (mab), southern blotting with four t. parva repetitive dna probes a ...	2001	11137270
trapping parasite secretory proteins in baker's yeast.	because the function of signal sequences has been conserved during evolution it has been possible to develop both bioinformatics resources to identify them and techniques to clone genes that encode secretory proteins. the latter entail insertion of heterologous signals upstream of signal peptide deleted reporter genes. we discuss the advantages of using saccharomyces cerevisiae for signal sequence trap technology. the yeast protein-translocation system appears to be less discriminating than that ...	2001	11530340
seroprevalences of vector-transmitted infections of small-holder dairy cattle in coastal kenya.	a cross-sectional study was carried out from july to september 1989 in kaloleni division, coast province, kenya to estimate the prevalence of vector-transmitted diseases in small-holder dairy cattle and to identify the risk factors associated with different management systems. one hundred and thirty of the 157 herds with dairy cattle in kaloleni division were surveyed. these were from three agro-ecological zones (coconut-cassava, cashew nut-cassava and livestock-millet), comprised two management ...	2001	11566374
a statistically derived index for classifying east coast fever reactions in cattle challenged with theileria parva under experimental conditions.	a statistically derived disease reaction index based on parasitological, clinical and haematological measurements observed in 309 5 to 8-month-old boran cattle following laboratory challenge with theileria parva is described. principal component analysis was applied to 13 measures including first appearance of schizonts, first appearance of piroplasms and first occurrence of pyrexia, together with the duration and severity of these symptoms, and white blood cell count. the first principal compon ...	2000	10811278
microsequence heterogeneity and expression of the lsu rrna genes within the two single copy ribosomal transcription units of theileria parva.	the nucleotide sequences of the large subunit ribosomal rna coding genes within the two single copy ribosomal dna transcription units of a cloned theileria parva isolate from a buffalo were determined. the two lsu rrna coding units differed by 11 nucleotide substitutions and two deletions of 1 and 6 bp, all located in the 5' end of the lsu coding region. we also observed microsequence heterogeneity between the two buffalo parasite lsu sequences and the previously determined lsu rrna gene of a t. ...	2000	11080596
pathological effects and reduced survival in rhipicephalus appendiculatus ticks infected with theileria parva protozoa.	pathological effects have been demonstrated in a number of arthropod species as a consequence of parasitic infection. this is usually manifest as reduced arthropod survival and/or fecundity. this paper describes the detrimental effects the protozoan parasite, theileria parva has on rhipicephalus appendiculatus ticks. r. appendiculatus ticks were dissected and sectioned at regular intervals during their nymph to adult moult after detaching from a t. parva infected calf, and assessed by light and ...	2000	10726991
theileria parva genomics reveals an atypical apicomplexan genome.	the discipline of genomics is setting new paradigms in research approaches to resolving problems in human and animal health. we propose to determine the genome sequence of theileria parva, a pathogen of cattle, using the random shotgun approach pioneered at the institute for genomic research (tigr). a number of features of the t. parva genome make it particularly suitable for this approach. the g+c content of genomic dna is about 31%, non-coding repetitive dna constitutes less than 1% of total d ...	2000	10731569
integrated molecular diagnosis of theileria and babesia species of cattle in italy.	a reverse line blot hybridization (rlb) test was developed to specifically identify six theileria spp. (t. annulata, t. parva, t. mutans, t. velifera, t. taurotragi, and t. buffeli/orientalis) and three babesia spp. (b. bovis, b. bigemina, and b. divergens). no cross reaction was observed with other livestock pathogens (such as anaplasma marginale, a. centrale, a. ovis, cowdria ruminantium, trypanosoma brucei, t. congolense, and t. vivax). this method was used to test bovine blood samples collec ...	2000	11193668
reciprocal cross-protection induced by sporozoite antigens spag-1 from theileria annulata and p67 from theileria parva.	theileria annulata and theileria parva both possess a major surface antigen on the sporozoite stage of the life-cycle, called spag-1 and p67, respectively. in each case, these antigens are vaccine candidates and have been shown to induce a degree of homologous protection in earlier work. these antigens share sequence homology and are serologically cross-reactive. here, we confirm that these antigens confer protection against homologous species challenge. more importantly, they mutually confer a ...	2000	10792761
differences in the epidemiology of theileriosis on smallholder dairy farms in contrasting agro-ecological and grazing strata of highland kenya.	a prospective cohort study was conducted in five purposively-sampled agro-ecological zone (aez)-grazing system strata in murang'a district, kenya, between march 1995 and june 1996. the study strata were selected based on a preliminary characterization study to represent the widest range of risks to east coast fever (ecf) in the district and included zero-grazing and open-grazing farms. in total, 225 calves from 188 smallholder farms were examined from birth to 6 months of age and visited within ...	2000	10813159
a highly sensitive, non-radioactive assay for t cell activation in cattle: applications in screening for antigens recognised by cd4(+) and cd8(+) t cells.	we describe a highly sensitive, non-radioactive assay for t cell activation, based on the rapid induction of class ii mhc expression by constitutively negative bovine endothelial cells, when cultured in the presence of supernatants derived from activated bovine t cells. we demonstrate the effectiveness of this assay in detecting rboifngamma and activation of immune cd4(+) and cd8(+) t cell lines and clones in response to specific antigen and transfected cos-7 cells, respectively. we also demonst ...	2000	10821950
a 32 kda surface antigen of theileria parva: characterization and immunization studies.	previous studies using monoclonal antibody (mab) 4c9 specific for a 32 kda antigen (p32) of theileria parva demonstrated expression of the antigen on the surface of the sporozoite, making it a potential antigen for sporozoite neutralization. a full-length cdna encoding the major merozoite/piroplasm surface antigen (mmpsa) of t. parva was cloned and expressed in bacteria. the expressed product reacted strongly with mab 4c9, demonstrating identity between the p32 and mmpsa of t. parva. using immun ...	2000	10874718
a theileria parva type 1 protein phosphatase activity.	the protozoan parasite theileria (spp. parva and annulata) infects bovine leukocytes and provokes a leukaemia-like disease in vivo. in this study, we have detected a type 1 serine/threonine phosphatase activity with phosphorylase a as a substrate, in protein extracts of parasites purified from infected b lymphocytes. in contrast to this type 1 activity, dose response experiments with okadaic acid (oa), a well characterised inhibitor of type 1 and 2a protein phosphatases, indicated that type 2a i ...	2000	10989153
polymorphic open reading frames encoding secretory proteins are located less than 3 kilobases from theileria parva telomeres.	polymorphic, multicopy gene families are frequently located in subtelomeric regions of the genomes of parasitic protozoa. theileria parva telomere-associated (ta) dna from two chromosomes contained long open reading frames (orfs) 54% identical at the n-termini, whose 3' ends were 2670 and 2680 bp from the telomeric repeats. probes derived from these orfs revealed related sequences close to additional telomeres. the 3' end of an unrelated orf was approximately 2720 bp from a third telomere. these ...	2000	11071289
the epidemiology of theileria parva infections on smallholder dairy farms in kenya.	the purpose of the study was to characterize the differences in epidemiology (risks of infection, morbidity, mortality) and potential control of east coast fever (ecf) between the selected strata. evidence of theileria parva infection was assessed by increased antibody levels as measured in an indirect elisa test by the percent positivity (pp) of serum samples relative to a strong positive reference serum. a prospective cohort study was conducted in five purposively sampled agroecological zone ( ...	2000	11193631