| the cyclical transmission of strains of trypanosoma congolense and t. vivax resistant to normal therapeutic doses of trypanocidal drugs. | | 1971 | 5130093 |
| the haematology and histopathology of trypanosoma congolense infection in cattle. i. introduction and histopathology. | | 1971 | 5164674 |
| the haematology and histopathology of trypanosoma congolense infection in cattle. 3. discussion and conclusions. | | 1971 | 5164675 |
| biological observation in quantitative tests of nippostrongylus brasiliensis acting as vector of trypanosoma brucei or trypanosoma congolense. | | 1970 | 5444855 |
| pathological and biochemical changes in rats infected concurrently with nippostrongylus brasiliensis and trypanosoma congolense. | | 1970 | 5535152 |
| trypanosoma congolense: infectivity for white mice. | | 1968 | 5726861 |
| local skin reactions in cattle at the site of infection with trypanosoma congolense by glossina morsitans and g. tachinoides. | | 1969 | 5824283 |
| the occurrence of a berenil-resistant trypanosoma congolense strain in northern nigeria. | | 1967 | 6067631 |
| distribution and attachment of trypanosoma (nannomonas) congolense in the proximal part of the proboscis of glossina morsitans morsitans. | the distribution and attachment of trypanosoma congolense were investigated in the proximal part of the proboscis of glossina m. morsitans. in the food canal, epimastigotes and trypomastigotes formed tufts or compact layers. trypanosomes were attached to the cuticle by their flagella, which formed zonar hemidesmosomes. the flagella were mostly attached parallel to the axis of the labrum and often pointed to its tip. foot-like processes of the flagella came into contact with adjacent flagella lea ... | 1980 | 6106351 |
| a comparative evaluation of the parasitological techniques currently available for the diagnosis of african trypanosomiasis in cattle. | the parasitological techniques currently in use for the diagnosis of african trypanosomiasis were compared in a series of experiments for their capacity to detect trypanosoma congolense, t. vivax and t. brucei in the blood of cattle. the darkground/phase contrast buffy coat method proved to be more sensitive than the haematocrit centrifugation technique, thick, thin and wet blood films in detecting t. congolense and t. vivax. on the other hand with t. brucei, mouse inoculation was the most sensi ... | 1982 | 6131590 |
| trypanosoma congolense: susceptibility of cattle to cyclical challenge. | cattle primed by cyclical infection with glossina morsitans morsitans infected with cloned derivatives of trypanosoma congolense and treated with the trypanocidal drug berenil after 3 or 4 weeks were immune to cyclical challenge with homologous clones 3 to 5 weeks later. in these animals, localized skin reactions (chancres) and parasitemia did not develop. the same results were obtained in cattle given a homologous superinfection without prior treatment. on the other hand, cattle subjected to a ... | 1983 | 6133773 |
| a simple classification of different types of trypanosomiasis occurring in four camel herds in selected areas of kenya. | camels from herds in four different areas of kenya were sampled at regular intervals over periods of 9-15 months and examined for the presence of trypanosomiasis. five hundred and eight camels divided into three age categories were studied. trypanosomiasis caused by t. evansi, t. brucei and t. congolense was shown to be present in varying degrees in all the herds. camels were divided into 5 types according to mortality, the presence or absence of circulating trypanosomes and antibody, and the pr ... | 1983 | 6141655 |
| a quantification of the risk of trypanosomiasis infection to cattle on the south kenya coast. | the number of trypanosome-infected bites received by cattle grazed around an 8 ha area of forest harbouring a semi-isolated population of glossina pallidipes austen was estimated. the absolute size of the tsetse population was determined by mark-release-recapture techniques, the tsetse host range by the identification of blood-meals, and trypanosome infection rates by dissection of samples of tsetse. feeding frequency was estimated and the number of cattle present was known. it was estimated tha ... | 1983 | 6142631 |
| trypanosoma vivax, t. congolense or t. brucei infection rates in glossina morsitans when maintained in vitro on the blood of goat or calf. | tenerals of glossina morsitans morsitans and g. m. centralis were infected with trypanosoma vivax, t. congolense or t. brucei by feeding mainly on infected goats and then maintained either in vivo on uninfected calves, goats or rabbits, or fed in vitro upon heparinised or defibrinated blood of goats or calves for 21 days for t. vivax and t. congolense and 30 days for t. brucei and then dissected. the observed differences in the infection rates for all three trypanosome species maintained on diff ... | 1984 | 6143482 |
| cerebral trypanosomiasis in cattle with mixed trypanosoma congolense and t. brucei brucei infections. | six boran steers were infected simultaneously with trypanosoma congolense and t. brucei brucei while another group of 3 was inoculated with t. b. brucei one year after infection with t. congolense. three further steers were infected with t. b. brucei alone. whereas, the six animals which received simultaneous infections developed clinical signs of cerebral trypanosomiasis as evidenced by depression, ataxia and occasional circling, those infected with t. b. brucei alone did not. at necropsy, 4 ou ... | 1984 | 6150618 |
| the appearance of isometamidium resistant trypanosoma congolense in west africa. | the frequent reappearance of patent parasitemia, mainly trypanosoma congolense, in cattle maintained under isometamidium prophylaxis in the upper volta indicated that drug-resistant forms might be appearing. to investigate this possibility, trypanosome stocks were isolated in mice, their isometamidium sensitivity estimated and compared to that of stocks isolated before drug use was widespread. most t. congolense stocks isolated in 1982-1983 were 4-8 times less sensitive to isometamidium than tho ... | 1984 | 6150619 |
| maintenance of glossina morsitans morsitans on antiserum to procyclic trypanosomes reduces infection rates with homologous and heterologous trypanosoma congolense stocks. | three experimental groups of male glossina morsitans morsitans were infected at their first feed with procyclic forms of different stocks of trypanosoma congolense and subsequently maintained on a diet containing rabbit antiserum to one of these stocks. control flies were similarly infected but were then maintained on normal rabbit serum. dissection of the flies 19-21 days post infection showed a reduction in both immature and mature infection rates in all groups fed on antiserum by comparison w ... | 1984 | 6150620 |
| in vitro cultivation of trypanosoma congolense: the production of infective metacyclic trypanosomes in cultures initiated from cloned stocks. | glossina morsitans were infected with two cloned stocks of t. congolense. the proboscides, foreguts and midguts of infected flies were then used as sources of trypanosomes in vitro at 28 degrees c in the presence of bovine dermal collagen explants. cultures were established in which trypanosomes differentiated into adhering colonies of epimastigote forms which could then be maintained and subcultured in eagle's minimum essential medium supplemented with foetal calf serum for over 40 weeks. withi ... | 1984 | 6152116 |
| studies on trypanosoma (nannomonas) congolense iv. experimental immunization of mice against tsetse fly challenge. | groups of mice were exposed to multiple bites by tsetse flies (glossina morsitans morsitans) infected with a clone of trypanosoma congolense spread over a periof of 8 days. the mice were subsequently treated with berenil 10 days after the first fly bite as were uninfected control mice. the group of mice which received 12--15 infectious fly bites on two occasions, 21 days apart, were subsequently resistant to infection when re-challenged by flies infected with the same clone of t. congolense. the ... | 1980 | 6155654 |
| isometamidium-dextran complex: toxicity and activity against trypanosoma vivax and trypanosoma congolense in rats and mice. | | 1980 | 6156522 |
| antigenic variation and the surface glycoproteins of trypanosoma congolense. | two trypanosoma congolense variant-specific glycoproteins, which are expressed sequentially during a relapsing infection, have been purified. the proteins, termed vsg-1 and vsg-2, both have a molecular weight of 53,000 as determined by sds polyacrylamide electrophoresis. when either antigen is electrophoresed through a ph gradient on an isoelectric focusing (ief) gel, it gives a characteristic spectrotype of three bands. the ief components of each vsg are antigenically similar to each other but ... | 1981 | 6163660 |
| trypanosoma congolense: surface glycoproteins of two early bloodstream variants. i. production of a relapsing infection in rodents. | | 1981 | 6168484 |
| reverse transcription of trypanosome variable antigen mrnas initiated by a specific oligonucleotide primer. | african trypanosomes change their antigenicity by successively expressing different members of a group of related but highly diverse proteins, the variant surface glycoproteins (vsgs). we describe a synthetic oligonucleotide that can prime specifically reverse transcription of vsg mrna out of total trypanosome poly(a)+ rna. the specificity of this priming was verified by cdna sequence analysis of the transcription products and by the demonstration of variant-specific hybridization of the individ ... | 1983 | 6188156 |
| all metacyclic variable antigen types of trypanosoma congolense identified using monoclonal antibodies. | vaccination against the tsetse-borne trypanosomiases has proved impossible because of the trypanosome's ability to generate a seemingly inexhaustible number of variable antigen types in the blood or tissues of the host. each variable antigen is a glycoprotein which forms a surface coat on the trypanosome and each glycoprotein is the product of a single gene. the full repertoire of such antigens has not been identified for any trypanosome serodeme (genotype) as yet, but the number of genes coding ... | 1983 | 6196642 |
| capacity of a cis-diammineplatinum[ii]-polyglutamic acid complex to cure trypanosoma congolense infections in mice. | a cis-diammineplatinum(ii)-polyglutamic acid complex proved to have marked trypanocidal activity in vivo. when 5 mg of platinum per kg was administered daily for 5 days or when 20 mg of platinum per kg was administered on days 1, 3, and 6, five of five treated trypanosoma congolense-infected mice were cured. in contrast, cis-platin was ineffective at all doses tested. we believe that the complex has a much higher therapeutic ratio than does uncomplexed drug because it is less toxic. | 1984 | 6201136 |
| common and isolate-restricted antigens of anaplasma marginale detected with monoclonal antibodies. | anaplasma marginale-infected erythrocytes were examined for the presence of maturation, isolate-restricted, and isolate-common antigens by indirect immunofluorescence with monoclonal antibodies. a panel of 18 monoclonal antibodies was used; none of the antibodies reacted with anaplasma ovis, babesia bigemina, babesia bovis, trypanosoma brucei, trypanosoma congolense, or uninfected bovine erythrocytes. antigens common to all six a. marginale isolates were detected by nine antibodies. single isola ... | 1984 | 6205996 |
| studies on glycerol kinase and its role in atp synthesis in trypanosoma brucei. | glycerol kinase of trypanosoma brucei has been shown to be capable of catalysing sn-glycerol-3-phosphate dependent adp phosphorylation for atp generation. the rate of this reaction (vr) is sufficient to account for the observed rate of glycerol production from anaerobic glucose metabolism by intact cells and to account for net atp synthesis. glycerol kinase has been purified by preparing a post-nuclear, particulate fraction and solubilizing the enzyme with 0.5% (w/v) triton x-100. this treatment ... | 1980 | 6258071 |
| antiparasitic structure-activity relationships of congocidine derivatives. | several congocidine analogs were synthesized and tested for in vivo activity against trypanosoma congolense and in vitro activity against amastigotes of leishmania tropica. the tripyrrole derivative, beta-([n-methyl-4-[n-methyl-4-(guanidinoacetamido)pyrrole-2-carboxamido]pyrrole -2-carboxamido]pyrrole-2-carboxamido)butyroamidine dihydrochloride, was less toxic and more active than congocidine. the guanidinoacetyl moiety appears to be a structural requirement for antiparasitic activity in the con ... | 1981 | 6267245 |
| immunosuppression in bovine trypanosomiasis: response of cattle infected with trypanosoma congolense to foot-and-mouth disease vaccination and subsequent live virus challenge. | the primary and secondary antibody responses to foot-and-mouth disease virus vaccine were examined in cattle infected with trypanosoma congolense and the response of some of these animals to live foot-and-mouth disease virus challenge was assessed. infected groups of cattle had rather lower antibody responses than uninfected control cattle after primary vaccination but the antibody titres were not significantly depressed until after secondary vaccination. these levels remained depressed for the ... | 1982 | 6285433 |
| rat liver glucose-6-phosphate dehydrogenase isozymes: influence of infection with trypanosoma. | glucose-6-phosphate dehydrogenase (g6pd) changes were studied in livers of rats inoculated with trypanosoma lewisi, trypanosoma rhodesiense, trypanosoma congolense and trypanosoma brucei. marked increases in g6pd were directly related to the degree of parasitemia. no essential differences in g6pd levels were seen in animals inoculated with physiological saline when compared with uninoculated controls. elevation of g6pd was observed only from day 10 to 20 in rats inoculated with t. lewisi. after ... | 1983 | 6349921 |
| improved field diagnostic technique for trypanosomiasis by use of a minicentrifuge. | | 1983 | 6356572 |
| comparison of blood smear and indirect fluorescent antibody techniques in detection of haemoparasite infections in trade cattle in nigeria. | the incidence of blood parasites in trade cattle was surveyed with emphasis on tick-borne parasites, using blood smears and immunofluorescent antibody (ifa) techniques. with the blood smear method, about 9 and 8.9% of cattle examined were found positive for babesia bigemina and anaplasma marginale, respectively. percentage infections with other parasites were 3.33, 1.92, 0.75, 0.75 and 0.58, respectively, for babesia bovis, trypanosoma brucei, anaplasma centrale, eperythrozoon and theileria spec ... | 1984 | 6369761 |
| experimental trypanosoma (nannomonas) congolense infection in microtus montanus. | seventy-two voles (microtus montanus) were infected with a strain of trypanosoma congolense of low virulence in mice to study their susceptibility and value as a tool for testing chemotherapeutic agents. the infection in microtus was highly virulent. parasitaemia was low to moderate. significant spleen and body weight changes were observed. blood capillaries of the heart, brain, kidneys and lungs were markedly dilated and numerous parasites were present in the dilatations, particularly in the he ... | 1984 | 6383235 |
| antibody levels during bovine hemoparasitic diseases: trypanosomiasis, anaplasmosis, and babesiosis. | | 1983 | 6399967 |
| immune depression in bovine trypanosomiasis: effects of acute and chronic trypanosoma congolense and chronic trypanosoma vivax infections on antibody response to brucella abortus vaccine. | cattle were vaccinated with brucella abortus (s19) vaccine during acute (25 days) and chronic (25 weeks) trypanosoma congolense and chronic trypanosoma vivax (25 weeks) infections in order to determine the effect of such infections on the antibody response to the vaccine. it was found that the specific antibody responses of igg1 and igg2 sub-classes were profoundly depressed (80%) in both the acute and chronic infections with t. congolense. whereas igm antibody response was also profoundly depre ... | 1983 | 6408588 |
| comparative aspects of purine metabolism in some african trypanosomes. | some enzymes of purine salvage were detected in the cell-free preparations from bloodstream forms of african trypanosomes: trypanosoma vivax; t. brucei and t. congolense. extracts of trypanosomes cleave adenosine and inosine hydrolytically except in t. congolense where adenosine cleavage was mediated by a phosphorylase. all the trypanosomes apparently lacked adenosine deaminase. adenine aminohydrolase was found only in t. vivax while adenosine monophosphate deaminase was detected in t. brucei an ... | 1983 | 6419098 |
| a calcium dependent endoribonuclease from trypanosoma congolense cytoplasm. | a major endoribonuclease whose activity depends on the presence of calcium ions was isolated from the cytoplasm of trypanosoma congolense. like the ca2+-dependent endoribonuclease of t. brucei cytoplasm, this enzyme degraded poly(a) preferentially but also degraded to a lesser extent poly(u), trna and rrna to give 5'-phosphoribosyl oligonucleotides. neither enzyme hydrolyzes poly(g) or dna. both ribonucleases are inhibited by polyanions and heavy metal ions, and are heat-labile; n-ethylmaleimide ... | 1984 | 6431285 |
| trypanosoma (nannomonas) congolense: analysis by fluorescein-conjugated plant lectins of surface saccharides of cloned variant antigen types differing in infectivity for mice. | surface saccharides of 4 cloned vats (variant antigen types) of trypanosoma (nannomonas) congolense, amnats (amherst nannomonas antigen types) 1.1, 1.2, 2.1, and 3.1, derived from 3 different stocks, were compared by fluorescein-conjugated, plant lectins using a quantitative fluorescence method. it was ascertained by the id63 assay that the 4 amnats differed in their infectivity for mice. the lectins employed for amnats 1.1, 2.1, and 3.1 were concanavalin a (con a), wheat germ agglutinin (wga), ... | 1984 | 6439842 |
| comparison of the levels of autofluorescence caused by fixatives in fluorescence assay on trypanosomes. | | 1984 | 6441838 |
| immunodepression in trypanosome-infected mice. vi. comparison of immune responses of different lymphoid organs. | mitogen stimulation of cells from various lymphoid organs of c3h/he mice chronically infected with an isolate of trypanosoma congolense was studied at different time intervals after infection, using concanavalin a (con a) and lipopolysaccharide (lps). at the same time, changes in the percentages of t, b and null lymphocytes in these organs were determined by immunofluorescence staining. the responses of t and b lymphocytes in the spleen were totally depressed, and the cellular composition was dr ... | 1981 | 6452282 |
| in vitro studies on the biosynthesis of the surface glycoprotein of trypanosoma congolense. | tritiated leucine, glucosamine, mannose, and galactose were incorporated into the variant specific surface glycoprotein (vsg) of trypanosoma congolense in vitro. the uptake of the precursors is shown by sds-polyacrylamide electrophoresis and fluorography, by assay of the radioactivity in immunoprecipitates obtained with specific antisera, and by the isolation of the labeled antigens by affinity chromatography on concanavalin a-sepharose and isoelectric focusing. the in vitro labeled vsg exhibits ... | 1984 | 6470988 |
| continuous cultivation of animal-infective bloodstream forms of an east african trypanosoma congolense stock. | | 1984 | 6486939 |
| studies on the influence of non-steroidal anti-inflammatory drugs upon trypanosomiasis in goats and sheep. | the non-steroidal anti-inflammatory drug (nsaid) flurbiprofen caused a rise in parasitaemia in goats infected with trypanosoma vivax, trypanosoma congolense and trypanosoma brucei. all trypanosome-infected goats treated with flurbiprofen showed many dividing trypanosomes. this also included the short-stumpy forms of t. brucei. in t. vivax-infected goats flurbiprofen treatment resulted in 100% mortality in the acute and chronic stages of the infection. the increase in parasitaemia of t. brucei in ... | 1984 | 6512919 |
| [parasitological, clinical and serological findings in dahomey cattle experimentally infected with trypanosoma congolense and t. brucei]. | | 1984 | 6525154 |
| a special case of trypanosoma congolense infection produced in laboratory mice. | | 1984 | 6527201 |
| detection of circulating trypanosomal antigens by enzyme immunoassay. | antisera raised against trypanosoma evansi and t. congolense were used in a double antibody sandwich enzyme immunosorbent assay (elisa) to detect trypanosomal antigens in sera from experimentally infected rabbits and goats. assays quantitated using reference antigen preparations and the homologous antisera showed that antigens could be detected at protein concentrations of 1.5 microgram ml-1. the antisera also cross-reacted with soluble antigens prepared from t. brucei and t. vivax at similar pr ... | 1984 | 6532328 |
| [probable number of trypanosoma (nannomonas) congolense transmitted by glossina morsitans]. | | 1984 | 6544954 |
| [demonstration of resistance to trypanocides among the species of trypanosoma congolense recently isolated in burkina]. | | 1984 | 6544959 |
| specific antibody responses to the variable surface glycoproteins of trypanosoma congolense in infected cattle. | sera from cattle infected with three trypanosoma congolense clones (ilnat 2.1, ilnat 3.1 and ilrad 588) derived from different stocks were analysed for the presence of specific antibodies against the surface glycoproteins (vsgs) of the infecting trypanosomes using the solid and liquid-phase radioimmunoassays and the neutralization of infectivity test. high levels of igm, igg1 and igg2 antibodies against the vsgs of the infecting variable antigen types (vats) as well as other vats that arose duri ... | 1983 | 6622055 |
| alternative pathway activation of complement by african trypanosomes lacking a glycoprotein coat. | an in vitro culture trypanosoma congolense cell line was established using the mammalian cell feeder layer system. one of the principle characteristics of this parasite was its ability to multiply in culture at 35 degrees c, as an uncoated trypanosome (lacking a glycoprotein surface coat) unlike the original blood stream form from which it was derived. this trypanosome was lysed when incubated in normal human serum in contrast to the parasite which possessed a surface coat. the lytic reaction as ... | 1983 | 6634218 |
| observation on drug resistance of trypanosoma (nannomonas) congolense and trypanosoma (duttonella) vivax in cattle at a feedlot in the northern ivory coast. | studies carried out on feedlot cattle show berenil at 7 mg/kg to be the treatment of choice in trypanosomiasis although repeated doses may be necessary. resistant strains of trypanosoma (duttonella) vivax and trypanosomas (nannomonas) congolense survived dosages of between 0.5 mg/kg and 1.0 mg/kg of trypamidium and were cross resistant to homidium bromide. | 1983 | 6636303 |
| studies in rabbits on the disposition and trypanocidal activity of the anti-trypanosomal drug, diminazene aceturate (berenil). | after intramuscular injection of 3.5 mg kg-1 to rabbits, diminazene aceturate shows biphasic pharmacokinetics with maximum blood and interstitial fluid concentrations occurring after 15 min and 3 h respectively. seven days after treatment, 40-50% of the dose had been excreted in the urine and 8-20% in faeces. highest diminazene residues were determined in liver: 7 days after dosage, residues of 40.53 +/- 4.00 micrograms g-1 were present, corresponding to 35-50% of the dose. the recommended dose ... | 1983 | 6652366 |
| natural agglutinins to african trypanosomes. | agglutinins to uncoated culture forms of the african trypanosomes, t. congolense and t.b. brucei were detected in sera from a variety of mammals not exposed to the parasites. the agglutinins in bovine serum were shown to be specific antibodies with opsonic properties selective for the species of trypanosome. these findings suggest a possible role for the glycoprotein coat in preventing access of cross-reacting antibodies to the plasma membrane of african trypanosomes. | 1983 | 6657292 |
| interference with anti-trypanosome immune responses in rabbits infected with cyclically-transmitted trypanosoma congolense. | rabbits were infected with two clones of antigenically distinct stocks of trypanosoma congolense transmitted through glossina morsitans. local skin reaction development and the appearance of neutralizing antibodies were followed in animals infected with one or other of the trypanosome stocks, with both stocks simultaneously or with both stocks consecutively. there was little difference in local skin reaction development on rabbits infected with a single stock or with both stocks simultaneously b ... | 1983 | 6657293 |
| immune mechanisms in c57b1 mice genetically resistant to trypanosoma congolense infection. ii. aspects of the humoral response. | some aspects of the humoral response in trypanotolerant c57b1 mice and susceptible a/j mice were investigated to determine the possible basis of trypanotolerance. when the hepatic uptake of 75se-labelled t. congolense by infected mice was measured as an index of antibody production, it was found that only c57b1 mice could remove circulating labelled parasites, this ability persisting for several weeks after infection. estimation of the immunoglobulin concentrations in both strains of mice showed ... | 1983 | 6657296 |
| enzyme polymorphism and the distribution of trypanosoma congolense isolates. | conditions were established for demonstrating, by electrophoresis, polymorphism in 12 soluble enzymes from trypanosoma congolense. three enzymes had identical mobilities in every stock, variation occurring among the remaining nine. enzyme profiles were determined in 78 stocks collected from various hosts in a number of african countries, and were used by the computer to establish relationships within the collection. the major groupings formed solely from the isoenzymes corresponded remarkably cl ... | 1983 | 6660953 |
| infection, immunity and the development of local skin reactions in rabbits infected with cyclically-transmitted stocks of trypanosoma congolense. | the development of local skin reactions following bites by tsetse flies (glossina morsitans) infected with trypanosoma congolense was observed in normal rabbits, in rabbits with concurrent infections with t. congolense and in rabbits challenged after immunization by infection and treatment. local reactions developed in normal rabbits within seven days of fly bite and were resolved by approximately 19 days after infection. in rabbits with concurrent infections no typical local reactions developed ... | 1983 | 6660964 |
| increase in jugular circulation of trypanosoma congolense in infected calves caused by effective trypanocides. | | 1983 | 6681919 |
| effect of trypanocides on jugular concentration of trypanosoma congolense in the west african dwarf sheep. | the effects of various trypanocides on parasitaemia was investigated in sheep experimentally-infected with trypanosoma congolense strain 58/98. intravenous injection of berenil at the height of the first parasitaemic wave increased jugular parasite concentration by 12 and 16 times at the 9th and 20th minute post-treatment, respectively. with pentamidine, maximum counts were 5.0-8.6 times zero-time concentration during the same periods. peak effects of samorin, novidium and ethidium were observed ... | 1983 | 6686383 |
| resistance of cattle to tsetse-transmitted challenge with trypanosoma brucei or trypanosoma congolense after spontaneous recovery from syringe-passaged infections. | groups of cattle were inoculated intravenously with cloned populations of bloodstream forms of trypanosoma brucei or trypanosoma congolense. all five steers infected with t. brucei iltat 2.1 and six of the eight steers infected with t. congolense il 13-e14 became aparasitemic within 16 and 32 weeks postinfection, respectively. examination of sera from animals infected with t. brucei by indirect immunofluorescence and neutralization assays revealed the presence of antibodies against all the metac ... | 1984 | 6693173 |
| serum factors and the maturation of trypanosoma congolense infections in glossina morsitans. | removal of certain components from pig or cow blood greatly reduces the maturation rate of trypanosoma congolense infections in glossina morsitans fed on such diets. in particular, delipidation of serum has the same effect as complete removal of dietary serum with few midgut infections reaching maturity. the addition of gamma-globulin to red cells partially restores the ability of immature infections to transform suggesting that serum lipids or other serum factors are not acting directly on midg ... | 1984 | 6695534 |
| sequences homologous to variant antigen mrna spliced leader in trypanosomatidae which do not undergo antigenic variation. | trypanosomes which parasitize mammals have evolved mechanisms to evade immune attack, such as the occupation of 'safe' intracellular sites (for example, trypanosoma cruzi), or antigenic variation, exemplified by the salivarian trypanosomes (for example, trypanosoma brucei). antigenic variation is mediated by sequential expression of single variant surface glycoprotein (vsg) genes, and often involves transposition of the active gene. every vsg transcript examined shares the same 5' terminal 35-nu ... | 1984 | 6709074 |
| the role of antibody and complement in the cellular response to trypanosoma congolense. | the in vitro cytotoxic response of bovine granulocytes and monocytes and of murine peritoneal macrophages against trypanosoma congolense in the presence of antibody, antibody plus complement or complement alone was assessed using luminol aided chemiluminescence as a second parameter for effector cell activation. neither cell type exhibited any trypanolysis exceeding that of antibodies and complement alone. the kinetics of the chemiluminescence response in the course of these reactions closely co ... | 1984 | 6713731 |
| trypanosoma congolense: genetic control of resistance to infection in mice. | primary isolates of trypanosoma congolense show a range of virulence in nmri mice. stabiliates derived from an isolate (dinderesso/80/crta/3) which showed moderate virulence in most nmri mice (moderate parasitemia and survival) were used in inbred mice. c57bl/6 were resistant with low parasitemia and survival. parasitemias were higher in males than females. balb/c were the most sensitive of the strains tested and died with fulminating parasitemia. inheritance of resistance, defined as low parasi ... | 1984 | 6714359 |
| growth of trypanosoma brucei gambiense, t. b. rhodesiense, and t. congolense in bone marrow cultures of genetically anemic sl/sld mice. | | 1984 | 6737165 |
| glycosyltransferase activities in golgi complex and endoplasmic reticulum fractions isolated from african trypanosomes. | highly enriched golgi complex and endoplasmic reticulum fractions were isolated from total microsomes obtained from trypanosoma brucei, trypanosoma congolense, and trypanosoma vivax, and tested for glycosyltransferase activity. purity of the fractions was assessed by electron microscopy as well as by biochemical analysis. the relative distribution of all the glycosyltransferases was remarkably similar for the three species of african trypanosomes studied. the golgi complex fraction contained mos ... | 1984 | 6746739 |
| structural studies on the major oligosaccharides in a variant surface glycoprotein of trypanosoma congolense. | the carbohydrate moieties in the four isotypes of a variant surface glycoprotein from trypanosoma congolense were analyzed. all variant surface glycoprotein isotypes were found to contain up to 15% by weight of d-galactose, d-mannose, and n-acetyl-d-glucosamine in molar ratios approaching 1:3.2:3.9 (isotypes i-iii) or 1:2.4:2.4 (isotype iv); in addition, the presence of sialic acid could be demonstrated. after metabolic labelling with d-[6-3h]glucosamine, the four isoglycoproteins were successiv ... | 1984 | 6749184 |
| the response of the murine lymphoid system to a chronic infection with trypanosoma congolense. ii. the lymph nodes, thymus and liver. | | 1982 | 6752363 |
| study on a proteolytic enzyme from trypanosoma congolense. purification and some biochemical properties. | a protease has been purified from trypanosoma congolense bloodstream forms by osmotic disruption, freeze-thawing of the cells, followed by chromatography using thiopropyl-sepharose and gel filtration. the enzyme is a thiolprotease. a combination of sds-polyacrylamide gel electrophoresis and contact print zymograms using casein as substrate showed a single proteolytic band with a molecular weight of 31 000. the isoelectric point of the enzyme as ascertained by isoelectric focusing extended from p ... | 1982 | 6755218 |
| depressed immunoconglutinin responses in calves experimentally infected with trypanosoma congolense. | contrary to expectation, immunoconglutinin levels failed to rise significantly in calves infected with trypanosoma congolense. in addition, it was shown that trypanosome infection appeared to inhibit the immunoconglutinin response to brucella abortus strain 19. the possible reasons for these findings are discussed. | 1980 | 6774392 |
| curative effect of alpha-difluoromethylornithine on fatal trypanosoma congolense infection in mice. | the curative effect of alpha-difluoromethylornithine (dfmo) on fatal t. congolense infection in mice was investigated using various concentrations administered orally in drinking water. permanent cure was achieved in mice receiving 4% for 3 days or 2% for 5 days. mice receiving less became parasitemic again but then, without any further treatment, resisted death due to trypanosomes for an average of 34.5 days, while untreated controls were dead within 8 days after trypanosomes were first seen in ... | 1982 | 6814025 |
| immune mechanisms in c57bl mice genetically resistant to trypanosoma congolense infection. i. effects of immune modulation. | the effect of immune modulation on the pattern and course of infection with t. congolense was investigated in a strain of mice (c57bl) which is known to possess a significant degree of trypanotolerance, and a susceptible strain (cflp) which rapidly succumbs to infection. immunosuppression of c57bl mice by splenectomy, cyclophosphamide treatment or gamma irradiation reduced their survival to near that of susceptible strains of mice. in contrast, attempts to enhance the immune response of suscepti ... | 1983 | 6828326 |
| the susceptibility of gamma-irradiated glossina palpalis palpalis at different ages to infection with trypanosoma congolense. | | 1983 | 6859970 |
| the effect of trypanosoma congolense infection on acquired immunity to the tick rhipicephalus appendiculatus. | | 1983 | 6882069 |
| congenital transmission of trypanosoma congolense in mice. | pregnant mice were infected with a strain of t. congolense which produces a chronic infection, to determine if congenital infection can occur. some of the mice were killed before delivery and tissues of foetuses injected into clean male mice. other mothers were allowed to deliver and the tissues of some of the 1-day-old young inoculated into male mice while the remaining members of each litter were suckled by the infected mother until weaning. some but not all males infected from foetuses and 1- ... | 1983 | 6886090 |
| partial protection of rats against trypanosoma congolense by passive transfer of igm. | | 1982 | 6891856 |
| the effect of double infections with trypanosomes and gastrointestinal nematodes on the productivity of sheep and goats in south mozambique. | the effect of simultaneous infections with trypanosomes (trypanosoma vivax and trypanosoma congolense) and gastrointestinal nematodes on the productivity of sheep and goats was studied in 20 animals (6 male goats and 14 male sheep) at a farm near maputo. the animals were divided into 4 groups which received either treatment against gastrointestinal nematodes, or against trypanosomes, or treatment against both, or no treatment at all. in two-weekly and later in weekly intervals body weight, packe ... | 1982 | 6892177 |
| studies on trypanosoma (nannomonas) congolense iii. antigenic variation in three cyclically transmitted stocks. | cyclical transmission of different variable antigen types of trypanosoma congolense stib 228 resulted in the development of metacyclic trypanosome populations which were similar in their variable antigen composition as judged by immunofluorescence and neutralization assays. the variable antigen types present in the ingested bloodstream populations were not found in the metacyclic populations. the bloodstream populations which were obtained from cyclically infected, irradiated (900 rad.) mice con ... | 1980 | 6992057 |
| response of the murine lymphoid system to a chronic infection with trypanosoma congolense. i. the spleen. | the response within the different cellular compartments of the spleen in mice infected with trypanosoma congolense was evaluated using histologic and cytologic methods and immunofluorescence to detect intracellular and cell surface immunoglobulin. the isolate of t. congolense used produces a chronic infection in c3h/he mice leading to death 40 to 70 days after inoculation. previous studies had shown that this infection resulted in a marked immunodepression as judged by a range of in vitro assays ... | 1981 | 7033658 |
| trypanosoma congolense: surface glycoproteins of two early bloodstream variants. iii. immunochemical characterization. | | 1982 | 7056338 |
| early events following challenge of cattle with tsetse infected with trypanosoma congolense: development of the local skin reaction. | a local skin reaction (chancre) was elicited in susceptible cattle after the successful feeding of glossina morsitans morsitans infected with one of two different cloned isolates of trypanosoma congolense. the chancre first appeared as a small 2 to 3 mm nodule at the site of the challenge as early as day 5 and reached maximum activity by days 10 to 13 when it had developed into a raised, indurated, hot, painful swelling measuring up to 100 mm in diameter. thereafter it declined in size and activ ... | 1982 | 7072104 |
| immune depression in african trypanosomiasis: the role of antigenic competition. | the capacity of trypanosome-infected cattle to mount an immune response to a simultaneous or subsequent challenge with other trypanosomes was investigated using various clones of trypanosoma congolense and t. brucei. in animals infected simultaneously with equal numbers of trypanosomes of two different clones, the variant-specific antibody response to one clone was severely depressed while the response to the other was not affected. in cattle infected with one clone and then subsequently challen ... | 1982 | 7075022 |
| inheritance of susceptibility to trypanosoma congolense infection in glossina morsitans. | | 1982 | 7092373 |
| trypanosoma congolense: thrombocyte survival in infected steers. | | 1982 | 7095072 |
| the susceptibility of glossina palpalis palpalis at different ages to infection with trypanosoma congolense. | | 1982 | 7103580 |
| cultivation of procyclic trypomastigotes of trypanosoma congolense in a semi-defined medium with direct adaptation from bloodstream forms. | bloodstream forms of trypanosoma congolense added to the semi-defined medium 109-c (minimum essential medium with earle's salts, 60 mm hepes, haemin, and heat-inactivated fbs) and incubated at 28 degrees c transformed into procyclic trypomastigotes. established cultures of the procyclic forms yielded up to 4.5 x 10(7) parasites/ml. the cultivated populations consisted only of trypomastigotes and were not infective for mice. the amino acids consumed to the greatest extent were glutamine, proline, ... | 1982 | 7113354 |
| ethidium bromide: pharmacokinetics and efficacy against trypanosme infections in rabbits and calves. | [14c]ethidium bromide has been used to determine drug levels in tissues and body fluids of rabbits and calves following intramuscular injection. uninfected and trypanosoma brucei- or trypanosoma congolense-infected animals were studied. blood and tissue fluid level reached a maximum with 1 h and then fell rapidly; after 96 h 80-90% of the radioactivity injected had been excreted, approximately one third in urine and two thirds in faeces. by 1 h after injection of 1 mg [14c]ethidium/kg into a t. ... | 1982 | 7122121 |
| interference in the establishment of superinfections with trypanosoma congolense in cattle. | to examine the influence of an established infection on subsequent challenge with another unrelated trypanosome serodeme, cattle were subjected to two challenges, 5 to 6 wk apart, with unrelated isolates of trypanosoma congolense. the primary infection inhibited the establishment of the second infection despite the initial absence of detectable antibody to the trypanosomes used for the second challenge. this was true whether the second challenge consisted of bloodstream forms of the parasite or ... | 1982 | 7131183 |
| in vitro phagocytic activity of neutrophils of various cattle breeds with and without trypanosoma congolense infection. | a simple in vitro-technique using latex beads was used for the investigation of the phagocytic activity of neutrophils in bovines of different breeds, infected and non-infected with t. congolense. it was found that the n'dama, assumed to be trypanotolerant, have a significantly higher number of neutrophils and neutrophils with phagocytic activity per mm3 blood, compared to the more susceptible zebu, the baoulé and the crossbreed m75, ranging between these two breeds. the first appearance of t. c ... | 1982 | 7135473 |
| cytotoxic effect of unilamellar detergent dialysis liposomes on trypanosoma brucei and trypanosoma congolense bloodstream forms in vitro. | | 1982 | 7138525 |
| activation of the alternative pathway of bovine complement by trypanosoma congolense. | homogenates of trypanosoma congolense and particulate and supernatant fractions thereof were, by two different techniques, shown to activate bovine complement via the alternative pathway. (1) all three preparations converted complement factor bbov to its split product b gamma 2 as demonstrated (a) qualitatively by immunoelectrophoresis and (b) quantitatively by radial immunodiffusion. (2) lysis of guinea-pig erythrocytes by bovine complement via the alternative pathway was inhibited by whole hom ... | 1982 | 7145463 |
| purification of trypanosoma brucei variable surface glycoproteins: analysis of degradation occurring during isolation. | trypanosoma brucei variable surface glycoproteins (vsgs), isolated from some antigenic types of trypanosomes, degraded during isolation. we show that this degradation occurred immediately after breakage of the organism, presumably because of liberation of internal enzymes, and resulted in heterogeneity of isolated vsgs with respect to charge and/or molecular weight. degradation and consequent heterogeneity of these vsgs could be abolished by releasing vsg from the trypanosome surface without bre ... | 1982 | 7177702 |
| cultivation of infective forms of trypanosoma congolense from trypanosomes in the proboscis of glossina morsitans. | two stocks of trypanosoma congolense were established in culture at 28 degrees c using trypanosomes from the proboscides of infective glossina morsitans. successful primary cultures were initiated by placing an infected tsetse proboscis beside a bovine dermal collagen explant in eagle's minimum essential medium supplemented with foetal calf serum. the trypanosomes multiplied rapidly in the medium and also gradually formed an adherent layer o the plastic surface of the culture vessel. three prima ... | 1981 | 7208105 |
| the quantitation of trypanosoma congolense in calves. iv. in vitro culture of myeloid and erythroid marrow cells. | myeloid and erythroid cultures were prepared from bone marrow aspirates taken from control and t. congolense infected neonatal and six-month-old calves. the aspirates obtained from the infected animals were more cellular than the controls and it was found that the removal of adherent cells prior to ficoll separation improved the sensitivity of the cultures to colony stimulating factors and removed the background connective tissue cells and megakaryocytes from the resulting colonies. there was an ... | 1980 | 7233539 |
| purification of the variant antigens of trypanosoma congolense: a new approach to the isolation of glycoproteins. | we describe a new and rapid method for the isolation and purification of the variant antigens of trypanosoma congolense. the procedure consists of (a) partial lysis of trypanosomes with dioxane, (b) lectin-affinity-chromatography with con a-sepharose, (c) electrophoretic desorption and concomitant separation of con a-sepharose-bound glycoproteins in a granulated electrofocusing gel, (d) electrophoretic elution of focused proteins from the granulated gel particles. the efficiency of each step was ... | 1981 | 7236702 |
| [effect of bovine sera on infectivity and pathogenicity of trypanosoma congolense in mice]. | | 1981 | 7247921 |
| experimental bovine trypanosomiasis (trypanosoma congolense). lack of relation of the level of parasitemia to the j blood group. | twenty-five holstein-friesian steers were experimentally infected with trypanosoma congolense eatro 1721. they were tested for their j blood group status. twelve steers were found to belong to ja blood group and thirteen steers were either js or jcs. the level of parasitemia did not significantly differ between these two groups of cattle. it was concluded that the level of parasitemia is not influenced by j blood group antigens. | 1981 | 7256834 |
| trypanosoma congolense: natural and acquired resistance in the bovine. | | 1981 | 7274369 |
| the in vitro response to mitogens of leucocytes from cattle infected with trypanosoma congolense. | the in vitro proliferative response of bovine leucocytes from peripheral blood to lps, pwm and con a was monitored during the course of infection with t. congolense. the stimulatory effect of lps and pwm on pbl was significantly decreased in infected cattle while the reduction of stimulatory response to con a was less marked. there was a high background proliferation of unstimulated leucocytes from infected cattle. this increase in background counts correlated with the parasitaemia in that both ... | 1981 | 7285394 |
| the susceptibility of young sheep and goats to an experimental trypanosoma congolense infection. | | 1981 | 7296022 |