| development of local skin reactions in rabbits infected with metacyclic forms of trypanosoma congolense cultured in vitro. | | 1981 | 7316583 |
| trypanosoma congolense: surface glycoproteins of two early bloodstream variants. ii. purification and partial chemical characterization. | | 1981 | 7318988 |
| sialic acids are responsible for charge heterogeneity of the variant surface glycoprotein of trypanosoma congolense. | intact living cells of trypanosoma congolense can be labeled by periodate/borotritide. the procedure described introduces a radioactive label nearly exclusively into the variant surface glycoprotein (vsg). the label can be removed from the vsg by either neuraminidase treatment or by mild acid hydrolysis. using thin-layer chromatography the labeled compounds comigrated with 5-acetamido [or 5-glycolamide]3,5-dideoxygalactooctulosonic acid and 5-acetamido [or 5-glycolamide]3,5-dideoxyarabinoheptulo ... | 1981 | 7329438 |
| trypanosomiasis in zebu cattle. reappearance of trypanosoma congolense in brain tissue after treatment with berenil. | | 1981 | 7335941 |
| the interaction of trypanosoma congolense and haemonchus contortus infections in 2 breeds of goat. 1. parasitology. | | 1981 | 7343578 |
| the interaction of trypanosoma congolense and haemonchus contortus infections in 2 breeds of goat. 2. haematology. | | 1981 | 7343579 |
| injury induced by trypanosoma congolense adhesion to cell membranes. | trypanosoma congolense binds to erythrocytes and the walls of the microvasculature. experiments were conducted to determine if the attachment of t. congolense, alone or in combination with antitrypanosome antibody, was damaging to host cells. bovine erythrocytes were labelled with 51cr and incubated with t. congolense to promote adhesion. plasma from the same donor as the red blood cells was added to the erythrocyte-trypanosome aggregates and the release of 51cr measured. there was a two- to thr ... | 1980 | 7365637 |
| immunosuppression in bovine trypanosomiasis. the establishment of "memory" in cattle infected with t. congolense and the effect of post infection serum on in vitro (3h)-thymidine uptake by lymphocytes and on leucocyte migration. | cattle infected with trypanosoma congolense were intravenously immunized with leptospira biflexa 15 days after trypanosomal infection. the primary immune response to l. biflexa was considerably reduced as compared to uninfected controls. the infected cattle mounted a secondary response when they were cured of trypanosomes by treatment with berenil 25 days after infection and re-immunized 8 days later. the mean secondary response in these previously infected animals was lower tha, but not signifi ... | 1980 | 7376244 |
| genetic resistance to trypanosoma congolense infections in mice. | the mechanisms of genetic resistance or "trypanotolerance" to infection with trypanosoma congolense were investigated in two strains of mice. one strain c57bl, is outstandingly resistant to most stabilates of t. congolense and can survive for over 80 days, whereas cflp, in common with most other strains, generally succumbs in less than 20 days. evaluation of several pathophysiological and immunological parameters showed that after infection both strains initially developed similar levels of para ... | 1980 | 7380550 |
| hemolytic complement and serum c3 levels in zebu cattle infected with trypanosoma congolense and trypanosoma vivax and the effect of trypanocidal treatment. | total hemolytic complement and c3 levels were found to drop to 6.25% and 50% of preinfection levels, respectively, during trypanosome infections. chemotherapeutic elimination of the trypanosomes with berenil led to recovery of preinfection levels within 7 days and 11 days when cattle infected with trypanosome congolense and trypanosoma vivax, respectively, were treated 37 days after onset of infection. recovery was slower in t. vivax-infected cattle treated on day 50. berenil treatment had no ef ... | 1980 | 7380555 |
| evidence for concanavalin a binding sites on the surface coat of trypanosoma congolense. | glycoproteins of trypanosoma congolense have been detected on sds-polyacrylamide gels using the concanavalin a peroxidase technique. using [35s]diazoniobenzenesulphonate as a marker for cell surface proteins it was possible to distinguish between internal glycoproteins and the surface coat proteins. on sds-polyacrylamide gels con a reacted with the surface coat proteins. results obtained from con a-induced agglutination of living trypanosomes indicated that sugars of the surface coat proteins we ... | 1980 | 7383705 |
| the effect of trypanosoma congolense and t vivax infections on the antibody response of cattle to live rinderpest virus vaccine. | infections with trypanosoma congolense or t vivax did not significantly depress the neutralising antibody response of cattle to live rinderpest vaccine when vaccination was carried out eight or 25 days after infection. | 1980 | 7414077 |
| the quantitation of trypanosoma congolense in calves. 1. hematological changes. | anemia due to trypanosoma congolense infection in neonatal and 6-month-old calves was hemolytic and moderately responsive. the red cells were macrocytic and normochromic in both groups of calves and the anemia was milder in infected neonatal calves compared to the 6-month-old calves. the neonatal calves maintained normal white blood cell counts and developed a lymphocytosis at two weeks of infection. the six-month-old calves developed mild neutropenic leukopenia at one week post-infection withou ... | 1980 | 7414679 |
| inhibition of leukopoiesis by sera from trypanosoma congolense infected calves: partial characterization of the inhibitory factor. | sera collected from calves infected with trypanosoma congolense inhibited bovine granulocyte/macrophage colony formation in vitro, but not erythroid colony formation. the inhibitor was found to be tca precipitable in nature and on sephadex g-200 chromatography, it was found to elute with the second major peak. sonicated t. brucei, t. congolense, and t. theileri added directly into the cultures had no effect on granulocyte/macrophage colony formation, but induced significant enhancement of erythr ... | 1980 | 7414680 |
| trypanosoma congolense: specific transformation in vitro of leukocytes from infected or immunized cattle. | | 1980 | 7428912 |
| the effects of trypanosoma congolense infection on the testis and epididymis of the goat. | | 1980 | 7437534 |
| uptake of purine bases and nucleosides in african trypanosomes. | uptake of radioactivity labelled purine bases and nucleosides by suspensions of trypanosoma brucei and trypanosoma congolense in bicine buffer was determined at 37 degrees c. with t. brucei, the rate of uptake of adenosine was much greater than that of the other compounds tested, the uptake of which decreased in the order adenine, inosine, guanosine and hypoxanthine. with t. brucei, adenosine uptake increased with concentration in a manner suggesting two mechanisms, one with high and the other w ... | 1980 | 7443300 |
| the quantitation of trypanosoma congolense in calves. ii. biochemical changes. | changes in serum electrolytes, osmolality, total proteins and protein fractions, lipid levels and organ function tests were determined in neonatal and 6-month-old calves infected with t. congolense treu 112 and control calves. there were no consistent changes in electrolytes or osmolality for either age group of calves. there was a decrease in total serum protein in the infected 6-month-old calves, caused by decreases in the albumin and beta 2-globulin fractions. the total serum protein level re ... | 1980 | 7445066 |
| the quantitation of trypanosoma congolense in calves. iii. a quantitative comparison of trypanosomes in jugular vein and microvasculature and tests of dispersing agents. | hemocytometer and cytofluorometric methods were used to count trypanosomes in the blood of neonatal and six-month-old calves infected with t. congolense. the correlation between these methods was highest in the six-month-old calves because their parasitemia was greater and the accuracy of cytofluorometric counting is reduced below 1,000 trypanosomes per microliter of blood. fine needle aspiration biopsies showed many trypanosomes marginated in cerebral cortical capillaries, but few in muscle or ... | 1980 | 7445067 |
| hydrogen peroxide destaining: a new method for removing non-specific stains in nitrocellulose membrane-based dot-elisa for the detection of trypanosomes in tsetse flies (glossina spp.). | gut samples prepared from laboratory-reared tsetse flies and applied in dots onto nitrocellulose (nc) membrane were found to stain the membrane with differing coloration and intensity. the stains were, predominantly, either reddish to brown or blackish-brown to black and occasionally greenish to almost colourless, depending on the stage of digestion of the bloodmeal in the fly. nc membrane strips applied with tsetse gut samples from t. brucei infected and uninfected control flies were tested wit ... | 1995 | 7490455 |
| the accumulation and compartmentalization of isometamidium chloride in trypanosoma congolense, monitored by its intrinsic fluorescence. | interaction of the trypanocide isometamidium chloride with components of trypanosoma congolense results in characteristic shifts in the intrinsic fluorescence of the drug. the specificity of this interaction was investigated by analysing the effects of various physicochemical manipulations on its fluorescence properties. the characteristic shifts involved a preferential increase in the intensity of one emission peak over the other, resulting in a systematic increase in the ratio of fluorescence ... | 1995 | 7492332 |
| identification of trypanosomes in animals, humans and glossina. | a number of biochemical methods are now available for the identification of african trypanosomes. the method of choice depends on the number of trypanosomes present in the sample and the taxonomic level required. dna probes based on repetitive dna elements allow identification to subgeneric (e.g. trypanozoon), species (e.g. trypanosoma congolense, t. simiae) or subspecific (e.g. t. congolense savannah) levels. these probes are particularly useful for identification of trypanosomes in the fly mid ... | 1994 | 7496192 |
| flagellum-mediated adhesion of trypanosoma congolense to bovine aorta endothelial cells. | we studied the interaction between trypanosoma congolense and bovine aorta endothelial (bae) cell monolayers. our findings suggest that trypanosomes adhere predominantly to the flattened, peripheral cell surface domains as well as to filamentous endothelial outgrowths that are present during in vitro cultivation in non-confluent monolayers. adhesion is mediated exclusively by the flagellum in a distinct geometrical order with respect to the flagellar cytoskeleton. thus, it is possible to define ... | 1995 | 7501641 |
| in vitro activation and detection of antibody-secreting cells from trypanosoma congolense-infected cattle. | b cells from the peripheral blood and spleen of trypanosoma congolense-infected cattle and from the peripheral blood of an uninfected cohort were analysed for ability to secrete antibody and for expression of surface antigens before and after in vitro culture with interleukin-2, lipopolysaccharide and pokeweed mitogen. antibody-secreting cells (asc) were only detected in lymphocytes from peripheral blood after in vitro stimulation. the frequency of asc was greater in cultures of lymphocytes from ... | 1994 | 7536707 |
| characterization of concanavalin a-binding glycoproteins from procyclic culture forms of trypanosoma congolense, t. simiae and t. brucei brucei. | concanavalin a-binding glycoproteins were obtained from procyclic culture forms (pcfs) of trypanosoma congolense, t. simiae, and t. b. brucei strains. sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) analysis revealed that glycoproteins of 38.5, 30.5, and 27 kda were conserved between the different species and strains of the procyclic parasites. there were few similarities in the profiles of the high-molecular-weight glycoconjugates between the parasites. monoclonal antibody ... | 1995 | 7539528 |
| catalytic and potentiometric characterization of e201d and e201q mutants of trypanosoma congolense trypanothione reductase. | trypanothione reductase is a member of the structurally and functionally well-characterized family of flavoprotein reductases, which catalyze the reduced pyridine nucleotide dependent reduction of their disulfide, peroxide, or metal ion substrates. trypanothione reductase is found in a wide variety of trypanosoma species, where the enzyme serves physiologically to protect the organism from oxidative stress and assists in maintaining low intracellular levels of hydrogen peroxide. the redox potent ... | 1995 | 7548022 |
| trypanosoma congolense: proliferative responses and interleukin production in lymph node cells of infected cattle. | t-cell-mediated immune responses to defined antigens of trypanosoma congolense were measured in cattle undergoing primary infection. the antigens used were the variable surface glycoprotein and two invariant antigens, a 33-kda cysteine protease (congopain) and a recombinant form of a 69-kda heat-shock protein. proliferative responses were highest during the second week postinfection and were detected in cells obtained from the lymph node draining the site of infection but not in peripheral blood ... | 1995 | 7556557 |
| molecular characterization of trypanosome species and subgroups within subgenus nannomonas. | restriction fragment length polymorphism (rflp) analysis of both genomic and kinetoplast dna from representative stocks from 3 trypanosoma congolense subgroups (savannah, forest, and kilifi), t. simiae and t. godfreyi, was used to investigate the relatedness of the different groups within subgenus nannomonas. dna probes for beta-tubulin and the ribosomal dna (rdna) locus were isolated from a t. congolense savannah genomic library; additional probes were generated by pcr amplification of mini-exo ... | 1995 | 7567098 |
| [absence of interaction between trypanosoma theileri infections with the diagnosis of animal trypanosomiasis by detection of circulating antigens]. | this work presents data gathered at the cirdes (centre international de recherche-développement sur l'elevage en zone subhumide) during epidemiological monitoring. the prevalence levels of trypanosoma vivax, trypanosoma congolense and trypansoma brucei obtained using antigen-detection elisa were compared in non-infected animals and in animals infected with trypanosoma theileri. the aim was to investigate whether there were any serological cross-reactions between t. theileri and the pathogenic tr ... | 1995 | 7569224 |
| disposition of diminazene aceturate (berenil) in trypanosome-infected pregnant and lactating cows. | three cows were repeatedly infected with different strains of trypanosoma congolense and treated intramuscularly each time with a different dose of diminazene aceturate (berenil). biphasic decline was observed of the maximal plasma drug levels, which were attained at 15 min after the first treatment and at 30 min after the second and third treatments. the rate constants for the distribution and terminal phases depended on the period of exposure to parasitaemia of the animal at the time of treatm ... | 1995 | 7571326 |
| the effect of l-thyroxine on the anaemia response in trypanosoma congolense infected rabbits. | the development of anaemia is a major pathological manifestation in chronic trypanosomosis. the anaemia in african trypanosomosis coincides with a marked decrease in plasma concentration of both thyroxine (t4) and 3,5,3' triiodothyronine (t3). to evaluate the effect of trypanosome-induced hypothyroidism on the development of anaemia, sexually mature white new zealand rabbits were used. three groups were set up, each of ten rabbits: one group was infected with trypanosoma congolense; the second g ... | 1995 | 7571327 |
| [antigenic variation and the problem of vaccines against african trypanosomes]. | african trypanosomes evade the immune response of their host through continuous changes of their major surface antigen, the vsg. this antigenic variation is achieved by either alternative activation of different expression sites for the vsg gene, or dna rearrangements occurring within a given site. several minor but invariant surface proteins have recently been characterized. this is especially the case for some surface receptors, which appear to be located in an invagination of the plasma membr ... | 1995 | 7581198 |
| are cd8 t cells involved in control of african trypanosomiasis in a natural host environment? | murine models have suggested that cd8 t cells might play a major parasite-promoting role in african trypanosomiasis. to assess the role of these cells in a natural host environment, we have depleted cd8 cells from boran cattle in vivo and subsequently infected these animals with trypanosoma congolense by tsetse fly challenge. following administration of a mouse monoclonal anti-bovine cd8 antibody, we have been able to achieve a depletion of more than 99.9% in peripheral blood, spleen, prescapula ... | 1995 | 7621872 |
| partial protection against natural trypanosomiasis after vaccination with a flagellar pocket antigen from trypanosoma brucei rhodesiense. | cattle that were inoculated with an antigen derived from the flagellar pocket of trypanosoma brucei rhodesiense and then infected with trypanosoma congolense and trypanosoma vivax were compared with unvaccinated cattle when both groups of cattle were placed in regions of kenya endemic for tsetse flies known to harbour t. congolense and t. vivax. in one trial, 90 cattle were employed, 40 untreated controls, 30 cattle given prior treatment with samorin, and 20 inoculated with a flagellar pocket (f ... | 1995 | 7625108 |
| frequency of diminazene-resistant trypanosomes in populations of trypanosoma congolense arising in infected animals following treatment with diminazene aceturate. | the frequency of trypanosomes resistant to diminazene aceturate at a dose of 25 mg/kg of body weight was investigated for populations of trypanosoma congolense il 3274 which reappeared in infected mice after intraperitoneal treatment with diminazene aceturate at the same dosage. at inoculum sizes of 10(2), 10(3), 10(4), 10(5), and 10(6) trypanosomes per mouse, the relapse populations were used to initiate infections in five groups of 100 mice each by the intravenous route. immediately after infe ... | 1995 | 7625797 |
| kinetoplastid membrane protein-11 (kmp-11) is differentially expressed during the life cycle of african trypanosomes and is found in a wide variety of kinetoplastid parasites. | an abundant 11-kda membrane protein was purified from african trypanosomes by organic solvent extraction and octyl-sepharose chromatography. this protein cross-reacts with monoclonal antibodies originally generated against the lipophosphoglycan-associated protein of leishmania donovani. immunoblot analysis showed that the 11-kda molecule was present in a variety of species of kinetoplastids. it was found in several species and subspecies of african trypanosomes and was present in low amounts in ... | 1995 | 7630374 |
| a novel in vitro screening assay for trypanocidal activity using the fluorescent dye bcecf-am. | a cell viability assay, using fluorescence measurements has been developed for the screening of new compounds against african trypanosomes. 2',7'-bis-(carboxyethyl)-5(6)-carboxyfluorescein-pentaacetoxymethyles ter (bcecf-am), an esterase substrate, was used in the assay as a marker for cell viability. fluorescence was quantified using an automated fluorescence scanner for multi-well plates. trypanosoma brucei rhodesiense, t. congolense, t. evansi and t. equiperdum from continuously growing cultu ... | 1995 | 7631128 |
| expression of garp, a major surface glycoprotein of trypanosoma congolense, on the surface of trypanosoma brucei: characterization and use as a selectable marker. | procyclic and epimastigote forms of trypanosoma congolense express an immunodominant glutamic acid/alanine-rich protein (garp) that covers the parasite surface. although garp shows no sequence similarity to procyclins from t. brucei, the general characteristics of the two sets of surface glycoproteins suggest that they have analogous functions, in much the same way that variant surface glycoproteins with unrelated primary sequences fulfil the same function in bloodstream form trypanosomes. since ... | 1995 | 7637714 |
| experimental trypanosoma congolense infection on naturally occurring ticks in n'dama and gobra zebu cattle. | the effects of experimental trypanosoma congolense infection in gambian n'dama and gobra zebu cattle on number of naturally-occurring adult ticks attaching were studied. an indirect fluorescent antibody test was performed to detect serological prevalence of cowdria ruminantium antibody. the intravenously imposed trypanosome infection did not result in significant (p > 0.05) differences in amblyomma variegatum and hyalomma spp. infestations between control and infected n'dama cattle. control n'da ... | 1994 | 7638002 |
| primary structure and partial characterization of a life-cycle-regulated cysteine protease from trypanosoma (nannomonas) congolense. | trypanosoma (nannomonas) congolense is an important pathogenic parasite of domestic livestock in africa. we have cloned a cdna encoding a prepro-cysteine protease of this protozoan, the sequence of which indicates it is an early mrna processing intermediate. northern analysis demonstrates a life-cycle-stage specificity similar to previously described enzymatic data. the deduced amino-acid sequence shows extensive similarity to cysteine proteases of other parasitic protozoa, as well as papain and ... | 1995 | 7642126 |
| the kinetics of maturation of trypanosome infections in tsetse. | estimates of the time delay between the infective bloodmeal and maturation (incubation or maturation time) for 4 trypanosome stocks (2 trypanozoon and 2 trypanosoma congolense) show that maturation time in tsetse is not a parasite species-specific constant. the mean incubation time of a trypanosoma brucei rhodesiense stock (eatro 2340 - 18 days) was not significantly different from one t. congolense stock (sikuda88 - 15.5 days) but was significantly greater than another (1/148 fly9 - 12.5 days). ... | 1995 | 7675533 |
| distribution of developmentally regulated trans-sialidases in the kinetoplastida and characterization of a shed trans-sialidase activity from procyclic trypanosoma congolense. | the expression of developmentally regulated sialidase and trans-sialidase activities in kinetoplastid protozoa was investigated. the occurrence of these enzymes was found not to be a common feature among the kinetoplastida, but to be restricted to distinct developmental life cycle stages of only a few species. while sialidases without trans-sialylating activities were demonstrated in trypanosoma vivax and t. rangeli, trans-sialidase activity is expressed throughout the brucei-group and in t. con ... | 1995 | 7676903 |
| comparison of isometamidium chloride and homidium bromide as prophylactic drugs for trypanosomiasis in cattle at nguruman, kenya. | the duration of prophylaxis provided by isometamidium chloride and homidium bromide, each at a dose rate of 1 mg kg-1 bodyweight, was compared in a 12-month field trial involving groups of 30 zebu cattle in south-west kenya. the trial took place between february 1990 and february 1991 and included several months of high trypanosome challenge. cattle in the prophylaxis groups were retreated on a group basis when 10% of the group had become infected since the previous group treatment. on this basi ... | 1995 | 7676909 |
| early stages of infection with trypanosoma congolense: parasite kinetics and expression of metacyclic variable antigen types. | trypanosoma congolense develops in the skin of sheep at the site of inoculation of metacyclic trypanosomes, forming a chancre containing large numbers of parasites. by cannulating the afferent and efferent lymphatic ducts draining the skin and regional lymph node, the progressive development and migration of trypanosomes from the chancre was monitored and the expression of metacyclic antigen types (m-vats) was determined. the kinetics of development of parasitosis in the afferent and efferent ly ... | 1994 | 7709859 |
| trypanosoma congolense infection in two dogs. | trypanosomiasis, caused by trypanosoma congolense, was diagnosed for the first time in israel in two boxer dogs imported from kenya. the dogs developed clinical signs two days after arrival and succumbed to the disease within four days. the major clinical and clinicopathological findings included anaemia, haemorrhages, lymphadenomegaly, hepatosplenomegaly and neurological signs. histopathology showed lymphocytic-plasmacytic infiltration in the skin, brain, meninges, kidney and liver. | 1995 | 7723295 |
| feeding behaviour of tsetse flies (glossina pallidipes austen) on trypanosoma-infected oxen in kenya. | an incomplete ring of electric nets was placed around oxen which were either uninfected, infected with trypanosoma vivax, or infected with t. congolense. the numbers of fed and unfed glossina pallidipes caught on the nets were used to estimate the attractiveness of the oxen to tsetse, and the feeding success of the tsetse on the oxen. oxen infected with t. congolense attracted more g. pallidipes than the other groups of oxen. taking into consideration daily variation in the abundance or activity ... | 1995 | 7724237 |
| trypanosoma congolense: comparative effects of a primary infection on bone marrow progenitor cells from n'dama and boran cattle. | using in vitro clonogenic assays, the changes in haemopoietic progenitor cell levels were compared in the bone marrow of three adult trypanotolerant n'dama cattle and three age-matched trypanosusceptible boran cattle over 17 weeks (119 days) of a primary trypanosoma congolense (clone il 1180) infection. as the infection progressed, a clear tendency of the parasitaemia to decrease was seen in the n'damas, while it remained high throughout the infection in the borans. the decline in the colony-for ... | 1995 | 7729476 |
| trypanosoma congolense: developmental regulation of protein kinases and tyrosine phosphorylation during the life cycle. | in higher eukaryotes, key steps in the control of growth and proliferation are regulated by protein phosphorylation. however, little is known about the role of protein phosphorylation in the developmental cycles of pathogenic protozoa. in trypanosoma brucei, only the bloodform and procyclic form stages can be obtained in sufficient numbers for biochemical analyses. however, the entire life cycle of trypanosoma congolense can be generated in vitro, providing sufficient material for analyses of th ... | 1995 | 7729486 |
| developmental regulation of rna editing and polyadenylation in four life cycle stages of trypanosoma congolense. | the accumulation of many edited mrnas is developmentally regulated in a transcript-specific fashion in trypanosoma brucei. in addition, these transcripts are frequently present in two size classes which differ substantially in the lengths of their poly(a) tails, and poly(a) tail length is also developmentally regulated. previously, these phenomena have only been studied in the mammalian bloodstream and insect procyclic forms (bf and pf, respectively) of t. brucei. in this paper, we examine devel ... | 1994 | 7739675 |
| glutathione reductase (ec 1.6.4.2.) in experimental trypanosomiasis. | the activity of glutathione reductase (ghsr) in extracts of kidney, liver and testis of rats infected with trypanosoma congolense decreased with every wave of parasitemia. the implications of these observations as they relate to the risk of oxidative stress are discussed. | 1995 | 7758150 |
| expression of trypanosoma congolense antigens in spodoptera frugiperda insect cells. | transcripts which encode two metacyclic-form-specific variable surface glycoproteins (mvsgs) of trypanosoma congolense il3000 have been cloned into baculovirus expression vectors using a novel transfer vector, pacl11. one of the recombinant baculoviruses (acvsg1) expressed a mvsg as a glycoprotein with a signal peptide which was cleaved in this expression system, whereas the other one (acvsg2) expressed an unprocessed protein. from 1 liter of culture containing 10(9) spodoptera frugiperda cells ... | 1995 | 7758544 |
| apparent rarity of diminazene-resistant trypanosomes in goats infected with a diminazene-resistant population of trypanosoma congolense. | experiments were carried out in goats to determine the frequency with which diminazene-resistant trypanosomes occur in parasite populations before and after the intramuscular treatment of the goats with diminazene aceturate. trypanosoma congolense il 3274, a diminazene-resistant clone, was used to initiate infections in three groups of five goats. the goats in the first group were treated with diminazene aceturate at a dose of 7.0 mg kg-1 bodyweight within 10 seconds of infection; one of the goa ... | 1995 | 7761687 |
| effects of trypanosoma congolense on pituitary and adrenocortical function in sheep: changes in the adrenal gland and cortisol secretion. | the effect of trypanosomiasis on adrenal function was studied in 10 pubertal scottish blackface rams infected with trypanosoma congolense and nine uninfected controls. plasma cortisol concentration was measured by radioimmunoassay in samples obtained twice a week for three weeks before infection and three times a week for 79 days after infection. there was a significant (p < 0.001) increase in cortisol concentration in all the infected rams after the onset of parasitaemia nine to 16 days after i ... | 1995 | 7761698 |
| effects of trypanosoma congolense on pituitary and adrenocortical function in sheep: responses to exogenous corticotrophin-releasing hormone. | to investigate whether the aberrations in adrenocortical and gonadal activity observed in trypanosomiasis may be induced by the refractoriness of the pituitary to hypothalamic liberins, the responses of the pituitary and adrenal glands and the testes to stimulation with ovine corticotrophin-releasing hormone (ocrh) were studied in rams 23 days (acute phase) and 65 days (chronic phase) after they were infected with trypanosoma congolense. on both occasions a peak of plasma acth was observed withi ... | 1995 | 7761699 |
| three genes and two isozymes: gene conversion and the compartmentalization and expression of the phosphoglycerate kinases of trypanosoma (nannomonas) congolense. | the glycosome, a microbody organelle found only in kinetoplastid protozoa, compartmentalizes the first six enzymes of glycolysis. in order to better understand the regulation and targeting of glycolytic enzymes in trypanosomes, we have cloned and analyzed the three genes of the phosphoglycerate kinase (pgk) complex of trypanosoma (nannomonas) congolense. the organization of the genes within the complex is similar to that of trypanosoma brucei brucei. the nucleotide and amino-acid sequences, incl ... | 1995 | 7770090 |
| pig trypanosomosis: prevalence and significance in the endemic middle belt zone of southern nigeria. | abattoir and field/market surveys of 1,954 crossbred pigs aged 6 to 30 months, for trypanosomosis in the middle belt zone of southern nigeria, revealed a 26.8 infection rate. of those infected, 66.5, 23.9 and 8.2 % were due to mixed, single trypanosoma brucei and t. congolense infections respectively. although 1.5 % of the infections were unidentified, there was no evidence of t simiae. the infection rate was significantly higher (p < 0.05) among the abattoir pigs (37.8 %) than among the farm pi ... | 1994 | 7770662 |
| trypanosome infections of the tsetse fly glossina pallidipes in the luangwa valley, zambia. | trypanosome infections of glossina pallidipes were investigated at a site in the luangwa valley, zambia between june 1991 and september 1992. almost 3700 flies were captured, dissected, screened for trypanosome infection, and aged using both wing fray and (for females) ovarian categories. dna probes were used to identify midgut infections. prevalences of mature infections were 6.2% trypanosoma vivax-type and 3.1% t. congolense-type (including low prevalances of t. brucei, t. simiae and another n ... | 1994 | 7772128 |
| relationships between host blood factors and proteases in glossina morsitans subspecies infected with trypanosoma congolense. | host blood effects on trypanosoma congolense establishment in glossina morsitans morsitans and glossina morsitans centralis were investigated using goat, rabbit, cow and rhinoceros blood. meals containing goat erythrocytes facilitated infection in g.m.morsitans, whereas meals containing goat plasma facilitated infection in g.m.centralis. goat blood effects were not observed in the presence of complementary rabbit blood components. n-acetyl-glucosamine (a midgut-lectin inhibitor) increased infect ... | 1995 | 7787223 |
| antitrypanosomal activity of phosphonylmethoxyalkylpurines. | phosphonylmethoxyalkylpurines and -pyrimidines exhibit potent activity against a broad spectrum of dna viruses. we evaluated some of these nucleotide analogues for antitrypanosomal activity in vitro and in mice. the most active compounds were (s)-9-(3-hydroxy-2-phosphonylmethoxypropyl) adenine (hpmpa) and (s)-9-(3-hydroxy-2-phosphonylmethoxypropyl)-2,6-diaminopurine (hpmpdap), which inhibited growth of trypanosoma brucei brucei by 50% (ec50 value) when incubated in vitro for 24 hr with 0.23-5.69 ... | 1994 | 7799144 |
| involvement of gamma delta t cells in immunity to trypanosomiasis. | in this study the involvement of peripheral gamma delta t cells, prepared by flow cytometry, in the immune response of cattle to primary infection with trypanosoma congolense was assessed. negligible in vitro proliferative responses were observed in gamma delta t cells isolated from trypanosusceptible boran (bos indicus) cattle at all stages examined post-infection when stimulated in vitro with parasite antigens. in contrast, both cd8+ t cells and gamma delta t cells from trypanotolerant n'dama ... | 1994 | 7821972 |
| the interaction of trypanosoma congolense with endothelial cells. | factors which affect adhesion of cultured trypanosoma congolense bloodstream forms to mammalian feeder cells have been examined. using an in vitro binding assay, the initial events following interaction of trypanosomes with bovine aorta endothelial (bae) cells were monitored by both light- and electron microscopy. metabolic inhibitors and other biochemicals were incubated with either cells or parasites, to test whether any inhibited the process. our findings suggest that adhesion of the parasite ... | 1994 | 7831098 |
| trypanosomatid cysteine protease activity may be enhanced by a kininogen-like moiety from host serum. | african trypanosomes contain cysteine proteases (trypanopains) the activity of which can be measured by in vitro digestion of fibrinogen, after electrophoresis in fibrinogen-containing sds/polyacrylamide gels. when assessed by this procedure, trypanopain from trypanosoma brucei (trypanopain-tb) is estimated to have a molecular mass of 28 kda. however, two additional bands of trypanopain activity (87 kda and 105 kda) are observed if serum is added to the trypanopain before electrophoresis. format ... | 1995 | 7832773 |
| effects of trypanosome and helminth infections on health and production parameters of village n'dama cattle in the gambia. | the effects of trypanosome and helminth infections on health and production parameters in 2000 village n'dama cattle were assessed periodically. blood examination showed trypanosoma congolense and trypanosoma vivax to be prevalent, while strongylid-type eggs were those most frequently encountered in faecal samples. a distinct seasonal fluctuation was detected for both blood levels of trypanosomes and helminth egg output. strongylid burden and trypanosome infection had significant negative effect ... | 1994 | 7839560 |
| effects of trypanosoma congolense infection in rams on the pulsatile secretion of lh and testosterone and responses to injection of gnrh. | changes in pulsatile secretion of lh and testosterone and responses to exogenous gnrh were assessed at different stages of trypanosoma congolense infection in rams. jugular blood samples were collected every 15 min for 6 h followed by immediate injection of gnrh (20 micrograms i.v.) and further sample collection after 10, 20, 40, 60, 80, 100 and 120 min. this sampling and injection regimen was performed 5 days before infection (day -5) and 23 and 52 days after infection. t. congolense infection ... | 1994 | 7861397 |
| immunosuppression in trypanotolerant n'dama cattle following trypanosoma congolense infection. | tsetse-transmitted trypanosoma congolense infection causes an impairment of in vitro t cell proliferative responses in boran (bos indicus) cattle. to assess the importance of this phenomenon as it may relate to the ability of trypanotolerant cattle to control infection with trypanosomes, t cell proliferative responses to mitogenic stimulus with concanavalin a were measured in n'dama (bos taurus) cattle throughout infection. the responses of peripheral blood mononuclear cells from boran and n'dam ... | 1993 | 7877852 |
| patterns of trypanosoma vivax and t. congolense infection differ in young n'dama cattle and their dams. | trypanosome infection was detected by the dark ground/phase contrast buffy coat microscopic technique in n'dama cattle in a high natural tsetse challenge situation in zaire. the data were used to compare the pattern of infection in very young animals and in their dams, and to evaluate how the pattern evolved in calves from birth to maturity, and thereafter in the different age groups represented by their dams. five hundred and fourteen calves were evaluated at 3 week intervals for an average of ... | 1994 | 7879376 |
| quantitative phenotyping of n'dama cattle for aspects of trypanotolerance under field tsetse challenge. | matching animal health and performance data were recorded over the 2 year period from weaning at 10 months of age on 255 n'dama cattle in a high natural tsetse challenge situation in zaire. four parameters that are regarded as possible indicators of trypanotolerance, species of trypanosomes detected, length of time parasitaemic, intensity of parasitaemia (parasitaemia score), and anaemic condition as estimated by packed cell volume (pcv) values, were measured and the relative effects of changes ... | 1994 | 7879377 |
| kinetoplast-associated proteins as potential drug targets and diagnostic markers for trypanosomiasis. | | 1994 | 7884235 |
| comparative chromatin analysis of trypanosoma congolense. | the chromatin of trypanosoma congolense was analyzed by electron microscopy. the chromatin is organized as nucleosome filaments but does not form a 30 nm fiber. there are five groups of histones, including a histone h1-like protein, which as a molecular weight within the range of the core histones, and is extremely hydrophilic. weak histone-histone interaction, a typical feature of trypanosome chromatin, was found. these results are similar to those for t. cruzi and t. b. brucei, but differ sign ... | 1994 | 7885250 |
| response of diminazene-resistant and diminazene-susceptible trypanosoma congolense to treatment with diminazene when occurring as a mixed infection in goats. | a study was carried out to determine whether a drug-resistant trypanosome population could influence the survival of a drug-sensitive population in mixed infections in goats. to identify both populations during the course of a mixed infection, a system for distinguishing them was developed; using a nucleotide sequence of a cdna that was derived from trypanosoma congolense ilnat 3.3 (il 1616), a pair of 20-mer primers was designed which, in a pcr, amplified a 900-bp sequence from the diminazene-s ... | 1994 | 7893173 |
| pharmacology of existing drugs for animal trypanosomiasis. | lack of much interest by the pharmaceutical industry to venture into development of new antitrypanosomal drugs has been a major stimulus to an intensification of research into the few existing drugs. those indicated for animal trypanosomiasis include: isometamidium, homidium and diminazene, used primarily against trypanosoma congolense, t. vivax and t. brucei; and quinapyramine, mainly indicated for use against t. evansi infections. a great deal of research effort has focused on development of p ... | 1993 | 7902656 |
| alterations in drug transport in resistant trypanosoma congolense. | the transport of isometamidium chloride (samorin) in trypanosoma congolense which were either sensitive or resistant to this widely used trypanocide was studied in vitro. significantly lower amounts of drug were accumulated over time by resistant than by sensitive trypanosomes. while no direct evidence could be obtained, indirect observations implied the involvement of an increased efflux of drug from the resistant trypanosomes. in both the resistant and sensitive parasites, drug transport was f ... | 1993 | 7902664 |
| an in vitro assay for drug sensitivity of trypanosoma congolense using in vitro-derived metacyclic trypanosomes. | the sensitivity of seven populations of t. congolense to the salts of three trypanocides, diminazene, isometamidium and homidium, were determined in vitro using in vitro-derived metacyclic trypanosomes. the trypanosomes were incubated at 35 degrees c for 48 h with various drug concentrations (0.5 ng-50 micrograms/ml) and then transferred to cultures containing bovine endothelial-cell monolayers, to assess their viability over the following 5 days as compared to control trypanosomes that had been ... | 1993 | 7902666 |
| drug sensitivity screening in vitro of populations of trypanosoma congolense originating from cattle and tsetse flies at nguruman, kenya. | an in vitro assay that utilises in vitro-derived metacyclic trypanosomes was used to determine the drug sensitivity of 7 populations of trypanosoma congolense collected from cattle and tsetse flies at nguruman; a trypanosomiasis-endemic area in southwest kenya. the metacyclic trypanosomes used in the assay were obtained from cultures initiated directly from either the blood of cattle with low levels of parasitaemia or from guts of infected tsetse flies. sensitivities to isometamidium chloride, d ... | 1993 | 7903133 |
| identification and characterization of an acidic major surface glycoprotein from procyclic stage trypanosoma congolense. | monoclonal antibodies (mabs) were derived against the procyclic culture form of trypanosoma congolense and 14 were selected which bound to the surface of living procyclics in immunofluorescence assays. these antibodies bound to procyclics and epimastigotes of t. congolense (both savannah-type and kilifi-type) and procyclics of trypanosoma simiae, but not to procyclics of other species of trypanosomes, to bloodstream forms of several species of trypanosomes or to leishmania, and were thus life cy ... | 1993 | 7903427 |
| tumour necrosis factor production by monocytes from cattle infected with trypanosoma (duttonella) vivax and trypanosoma (nannomonas) congolense: possible association with severity of anaemia associated with the disease. | plasma of cattle infected with trypanosoma vivax il2337 was analysed for the presence of bovine tumour necrosis factor (tnf) by eia in which tnf was captured by a monoclonal antibody (moab bc9) and detected by a rabbit polyclonal antiserum. at week 2-3 post infection (p.i.) only a low activity was detected. therefore, an alternative approach was used in which tnf production was measured ex vivo. monocytes from t. vivax il2337-infected cattle manifested a strong tnf production which peaked around ... | 1994 | 7908735 |
| [comparison of experimental trypanosomiasis in various breeds of small ruminants in burkina faso]. | twenty-four dwarf djallonké sheep and goats, and 16 sahelian fulani sheep and goats, were inoculated with strains of trypanosoma vivax and trypanosoma congolense to compare their degree of susceptibility to trypanosomosis. one animal from each breed was used as a control. anaemia was observed in all inoculated animals. in the group of animals inoculated with t. vivax, 1 djallonké goat out of 6, 3 sahelian goats out of 4 and 2 fulani sheep out of 4 died within the experimental period of 16 weeks. ... | 1993 | 7915427 |
| the structure, organization, and expression of the leishmania donovani gene encoding trypanothione reductase. | trypanothione reductase (tr) is an nadph-dependent flavoprotein oxidoreductase central to thiol metabolism in the trypanosomatids. we report here the cloning by expression of the leishmania donovani gene. it is single copy, expresses a 2.6-kb transcript and a 52-kda protein and is located on a 1.1-mbp chromosome. the 491 amino acid sequence has 76% similarity to crithidia fasciculata and 67% similarity to trypanosoma cruzi, trypanosoma congolense and trypanosoma brucei tr. residues recognising t ... | 1994 | 7935607 |
| trypanosoma brucei, t. congolense and t. vivax infections in horses on a farm in kenya. | equines are particularly susceptible to infection with trypanosoma evansi and t. brucei, but rarely is natural t. congolense and t. vivax infection seen in horses. an outbreak of trypanosomosis occurred in a herd of horses used for patrolling the pineapple fields on the del monte farm, thika, kenya initially involving 6 horses. on subsequent screening of the entire group, t. brucei, t. congolense and t. vivax infections were detected in 16 of the 35 horses. the tests used for diagnosis included ... | 1994 | 7941037 |
| dna content and molecular karyotype of trypanosomes of the subgenus nannomonas. | the relative dna contents of representative stocks of 5 groups within the trypanosome subgenus nannomonas (trypanosoma simiae, godfreyi, t. congolense savannah, forest and kilifi) were measured by flow cytometry. the range of dna contents formed a continuum. nevertheless small differences were observed between the groups, with t. simiae/t. congolense savannah and t. congolense kilifi/forest at the lower and higher ends of the range respectively. analysis of karyotype by pulsed field gel electrop ... | 1994 | 7942351 |
| chinifur, a selective inhibitor and "subversive substrate" for trypanosoma congolense trypanothione reductase. | nitrofurans with aromatic and heterocyclic substituents inhibit trypanosoma congolense trypanothione reductase (tr) and yeast glutathione reductase (gr), acting as uncompetitive inhibitors vs. nadph and noncompetitive or uncompetitive inhibitors vs. disulfide substrate. many of these compounds inhibited trypanothione reductase more efficiently than glutathione reductase. chinifur (2-[5'-nitro(furo-2'-yl)-ethene-1-yl]-4(n,n-diethylamino)-1-methyl-but-1 -yl - aminocarbonyl-4-quinoline) was the mos ... | 1994 | 7945363 |
| detection of trypanosome infections in the saliva of tsetse flies and buffy-coat samples from antigenaemic but aparasitaemic cattle. | relatively simple protocols employing non-radioactive dna probes have been used for the detection of african trypanosomes in the blood of mammalian hosts and the saliva of live tsetse flies. in combination with the polymerase chain reaction (pcr), the protocols revealed trypanosomes in buffy-coat samples from antigenaemic but aparasitaemic cattle and in the saliva of live, infected tsetse flies. furthermore, the protocols were used to demonstrate concurrent natural infections of single tsetse fl ... | 1994 | 8022657 |
| protection conferred by trypanosoma evansi infection against homologous and heterologous trypanosome challenge in rabbits. | the response of rabbits, infected with trypanosoma evansi, to challenge with homologous and heterologous trypanosome species was investigated. protection against homologous challenge was complete with partial protection observed against heterologous t. evansi and trypanosoma brucei challenge. no protection was seen against challenges with trypanosoma vivax or trypanosoma congolense. the recognition of the surface components of the parasite by the host antibodies was closely linked with complete ... | 1994 | 8030185 |
| dynamics of host blood effects in glossina morsitans sspp. infected with trypanosoma congolense and t. brucei. | the pattern of infection in glossina morsitans morsitans and g. m. centralis membrane-fed on eland, buffalo or goat blood mixed with trypanosoma congolense or t. brucei was studied from day 1 to day 10. tsetse were initially permissive vectors, with most flies harbouring infections of 10(4)-10(5) parasites on day 3. however, after a second blood meal on day 3, flies cleared many infections, with g. m. morsitans clearing more infections than g.m. centralis. infective feeds of goat blood consisten ... | 1994 | 8036228 |
| sequence determination of three variable surface glycoproteins from trypanosoma congolense. conserved sequence and structural motifs. | the full-length cdna sequences of three variable surface glycoproteins from bloodstream forms of trypanosoma congolense have been determined. they encode preproteins of 429, 449, and 428 amino acids. these proteins contain the typical n-terminal leader sequences of secreted eukaryotic proteins, and display hydrophobic amino acids at their c-termini characteristic of variable surface glycoproteins; these leader sequences serve as transient membrane anchors after protein synthesis. by performing s ... | 1994 | 8055958 |
| maturation of trypanosome infections in tsetse. | | 1994 | 8056082 |
| immunoelectron microscopic studies on the specific adhesion of trypanosoma congolense to cultured vascular endothelial cells. | bloodstream forms of trypanosoma congolense were cocultivated in vitro with vascular endothelial cells. the trypanosomes adhere specifically to the endothelial surfaces of the anterior part of their flagella, as shown by scanning and transmission electron microscopy. the interaction between parasite and host cell is very tight, and frequently the accumulation of endocytotic vesicles near the contact site is observed. immunoelectron microscopy revealed a compound distributed over the total surfac ... | 1994 | 8060730 |
| [ticks and hemoparasitoses in livestock in senegal. v. the northern guinea area]. | the authors report the results of a study on ticks and hemoparasitoses among cattle, sheep and goats in the north-guinean zone. during a period of 15 months, ticks were systematically removed from 40 cattle, 40 sheep and 40 goats in order to assess the population dynamics and to determine more accurately the preferential sites of settlement of the following different species collected from these animals: amblyomma variegatum, boophilus geigyi, hyalomma truncatum, h. marginatum rufipes, rhipiceph ... | 1993 | 8073170 |
| time-dose response of trypanosoma congolense bloodstream forms to diminazene and isometamidium. | trypanosoma congolense bloodstream forms were propagated in vitro axenically in a simplified cultivation medium at 34 degrees c. viability of a drug-sensitive and a drug-resistant clone were examined for 10 days following exposure to 0.1, 1.0 and 10.0 micrograms ml-1 of diminazene aceturate and 0.1, 1.0 and 10.0 ng ml-1 of isometamidium chloride for various time intervals. drug-sensitive t. congolense were irreversibly damaged after incubation with 10 micrograms ml-1 or 1 microgram ml-1 diminaze ... | 1994 | 8073607 |
| a 69 kda immunodominant antigen of trypanosoma (nannomonas) congolense is homologous to immunoglobulin heavy chain binding protein (bip). | an immunodominant antigen in trypanosoma congolense-infected cattle is a 69 kda protein which is conserved among species and developmental stages of african trypanosomes. immunoscreening of a cdna expression library identified a 2.35 kbp clone which contains a complete open reading frame encoding a protein of 653 amino acids with a predicted molecular mass of 71 kda. protein sequence analyses revealed 45-65% identity with hsp70s from a broad range of organisms, the highest homology being with th ... | 1994 | 8084662 |
| respiratory activity of isolated liver mitochondria following trypanosoma congolense infection in rabbits: the role of thyroxine. | 1. the effect of trypanosome infection on rabbit liver mitochondrial oxidative phosphorylation was investigated, with and without thyroxine replacement. 2. state 3 respiration, respiratory control ratio (rcr) and adp/o ratio were significantly reduced in mitochondria from trypanosome-infected animals whereas there was no change in state 4 respiration. 3. state 3 respiration, rcr and adp/o ratio were not significantly altered in trypanosome-infected animals given thyroxine replacement therapy. 4. ... | 1993 | 8095444 |
| the relationship between decrease in feed intake and infection with trypanosoma congolense and t. vivax in west african dwarf goats. | twenty-three mature dwarf goats were used to study whether there is a relationship between the decrease in feed intake for individual goats and infection with t.congolense and t. vivax. furthermore, it was investigated how rectal temperatures and blood parameters were affected by the t. congolense infection and how changes in these parameters can be used to predict the effect of a t. vivax infection on feed intake. for individual goats a ranking correlation was found between relative dry matter ... | 1993 | 8098884 |
| epidemiology of bovine trypanosomiasis in the ghibe valley, southwest ethiopia. 2. factors associated with variations in trypanosome prevalence, incidence of new infections and prevalence of recurrent infections. | an average of 840 east african zebu cattle from nine herds in the ghibe valley, southwest ethiopia were monitored from january 1986 to april 1990. each month blood samples were collected for analysis of packed red cell volume (pcv) and detection of trypanosomes. animals found to be parasitaemic and with a pcv less than 26% were treated with diminazene aceturate at a dose of 3.5 mg/kg body weight. the majority of infections were associated with trypanosoma congolense (84% of infections in adult c ... | 1993 | 8098899 |
| epidemiology of bovine trypanosomiasis in the ghibe valley, southwest ethiopia. 3. occurrence of populations of trypanosoma congolense resistant to diminazene, isometamidium and homidium. | in july 1989, blood samples were collected from parasitaemic cattle in the ghibe valley, ethiopia, frozen in liquid nitrogen and transported to nairobi, kenya. twelve of the stabilates were inoculated into individual boran (bos indicus) calves and characterised for their sensitivity, in turn, to diminazene aceturate (berenil), isometamidium chloride (samorin) and homidium chloride (novidium). all 12 stabilates produced infections which were shown to be trypanosoma congolense and resistant to tre ... | 1993 | 8098900 |
| comparative pharmacokinetics of diminazene in noninfected boran (bos indicus) cattle and boran cattle infected with trypanosoma congolense. | the pharmacokinetics of diminazene in five female boran (bos indicus) cattle before and then during acute and chronic phases of experimental infections with trypanosoma congolense were investigated. a 7.0% (wt/vol) solution of diminazene aceturate (berenil) was used in all three phases of the study and administered as a single intramuscular dose of 3.5 mg of diminazene base per kg of body weight. there were no significant differences between the values of pharmacokinetic parameters for the nonin ... | 1993 | 8100129 |
| the glutamyl binding site of trypanothione reductase from crithidia fasciculata: enzyme kinetic properties of gamma-glutamyl-modified substrate analogues. | trypanothione reductase, central to the redox defense systems of parasitic trypanosomes and leishmanias, is sufficiently different in its substrate-specificity from mammalian glutathione reductase to represent an attractive target for chemotherapeutic intervention. previous studies of the physiological substrates trypanothione (n1,n8-bis(glutathionyl)spermidine) and n1-glutathionylspermidine disulphide established that the spermidine moiety of these substrates can be replaced by the 3-dimethyl-p ... | 1993 | 8105896 |
| mechanism of reduction of quinones by trypanosoma congolense trypanothione reductase. | a number of quinones were analyzed as substrates for trypanothione reductase from trypanosoma congolense, an enzyme responsible for the protection of trypanosomes against oxidative stress. using nadph as substrate, the maximal rate of the steady-state reaction at ph 7.5 was between 24 and 1.6 s-1 for 11 quinone substrates. the biomolecular steady-state rate constants for quinone reduction, v/km, ranged from 240 to 1.9 x 10(5) m-1 s-1, and their logarithms exhibited a hyperbolic dependence on the ... | 1994 | 8117712 |
| modulation of the phenotype and function of bovine afferent lymph cells during infection with trypanosoma congolense. | alterations in the phenotype and function of cells isolated from bovine afferent lymph were studied following tsetse-transmitted trypanosoma congolense infection. little alteration was observed in the output of the cd2+ t cells in the lymph, and within this population the cd4:cd8 ratio remained relatively constant. by contrast, a marked decrease was observed in the output of gamma delta t cells over the first 7 days following infection. the number of b cells increased between 2 and 6 days post-i ... | 1994 | 8128607 |
| [pathogenic effects of trypanosoma congolense on the testis of baoulé bulls: quantitative and morphometric histology]. | the effect of trypanosoma congolense on testis was studied in 53 trypano-resistant "baoulé" bulls by quantitative histology and morphometry. the daily spermatozoa production per testis of control groups (n = 45) was 382 +/- 334 x 10(6) (m +/- sd) and the epididymis contained 0.6 +/- 1 x 10(9) spermatozoa in the caput, 0.3 +/- 0.3 x 10(9) in the corpus and 1.2 +/- 1.8 x 10(9) in the cauda. the infected bulls (n = 8) showed no significant difference (p > 0.05) when compared to the control despite ... | 1993 | 8142035 |
| heligmosomoides polygyrus and trypanosoma congolense infections in mice: a laboratory model for concurrent gastrointestinal nematode and trypanosome infections. | a murine model using heligmosomoides polygyrus and trypanosoma congolense has been developed for studying the effects of concurrent chronic gastrointestinal nematode and trypanosome infections. female outbred mice were infected either with 500 infective larvae (l3) of h. polygyrus or with 10(4) bloodstream forms of t. congolense or both. in concurrent infections, animals were dosed with both parasites simultaneously or the trypanosomes were injected 5 or 10 days after the mice were infected with ... | 1994 | 8152856 |