| lectin signalling of maturation of t. congolense infections in tsetse. | the process of maturation of trypanosoma congolense broden in tsetse has been shown to be initiated by lectin secreted in the fly midgut. in the present study the duration of lectin signal required to induce maturation was determined by the sequential addition or removal of a specific lectin inhibitor (d+glucosamine) to the diet of infected male glossina morsitans westwood. an established midgut infection of t.congolense was found to require, at most, 72 h exposure to midgut lectin to begin the ... | 1989 | 2519657 |
| use of dna probes to identify trypanosoma congolense and t. simiae in tsetse flies from the gambia. | species- and strain-specific dna probes were used to identify patent midgut infections in glossina morsitans submorsitans and g. palpalis gambiensis captured at four sites in the gambia. 52% of mature nannomonas infections and 12% of immature infections were identified. trypanosoma (nannomonas) simiae accounted for the majority of identified infections in g.m. submorsitans, indicating the importance of distinguishing this species from the closely related t.(n) congolense when assessing the trypa ... | 1989 | 2566262 |
| rickettsial infections of midgut cells are not associated with susceptibility of glossina morsitans centralis to trypanosoma congolense infection. | teneral and 30-day old non-teneral glossini morsitans centralis, from a laboratory-bred colony, were fed on a goat infected with trypanosoma congolense clone il 1180. they were then maintained on an uninfected rabbit, and dissected on day 30 after the infected feed. the midgut infection rates were 38.1% and 8.1%, with the mature infection rates of 28.7% and 4.3%, respectively. electron microscopical examination revealed the presence of rickettsia-like organisms (rlos) within the mycetomes and th ... | 1989 | 2571249 |
| effect of african trypanosomiasis on plasma cortisol and thyroxine concentration in goats. | changes in plasma cortisol and thyroxine (t4) levels were measured weekly in female goats experimentally infected with trypanosoma congolense. values for plasma cortisol (range 10 to 25 nmol litre-1) and t4 (range 65 to 120 nmol litre-1) were within normal ranges in all goats before infection and in control animals throughout the 24 weeks of study. cortisol/t4 ratios of 0.23 to 0.15 (or 1:4 to 1:7) were obtained. in the infected goats a significant increase in cortisol and decline in t4 were sim ... | 1989 | 2595089 |
| a single trypanosome is sufficient to infect a tsetse fly. | | 1989 | 2604482 |
| [animal reservoir hosts of trypanosoma brucei gambiense in zaire: trypanosome infections in two foci in bas-zaire]. | the prevalence of trypanosoma spp. infections in domestic animals was estimated in a forest (boma) and a savanna (kimpese) sleeping focus in bas-zaire. the miniature anion-exchange centrifugation technique was used to determine the infection rates with t. congolense, t. vivax and t. brucei spp. in 505 animals. t. congolense predominated in both foci with the highest prevalence in pigs (76.2%), followed by sheep (31.3%), dogs (30.6%) and goats (7.4%). t. vivax was seen only on two occasions. in t ... | 1989 | 2617030 |
| antigen-detection enzyme immunoassays for the diagnosis of trypanosoma vivax, t. congolense and t. brucei infections in cattle. | species-specific monoclonal antibodies against trypanosoma vivax, t. congolense and t. brucei were used to develop antigen-capture enzyme-linked immunosorbent assays (antigen-elisa) for the diagnosis of bovine trypanosomiasis. each assay was subsequently used for the detection of species-specific circulating antigens in sera of cattle experimentally infected by tsetse transmission. in t. vivax and in t. congolense-infected animals, circulating antigens were detected as early as 10-12 days post-i ... | 1989 | 2617031 |
| trypanosome infection rate of glossina morsitans submorsitans in bahr el arab, south darfur province, sudan. | trypanosome infection rate of glossina morsitans submorsitans in bahr el arab fly belt, sudan was investigated in four areas using fly rounds with screen and bait animals together with traps during the dry season february to may 1985. the overall infection rate of tests flies captured in the four areas was 5.1%. the infection rate of vivax group trypanosomes comprised 64.7% of total infections, congolense group 31.2% and brucei group trypanosomes 3.9%: 27.3% of the vivax and 31.3% of the congole ... | 1989 | 2617680 |
| [leukocyte migration inhibition after experimental trypanosome infection in cattle]. | blood serum from cattle experimentally infected with trypanosomes was tested for its activity influencing granulocyte migration. pooled porcine granulocytes were used in the migration assay. the inhibitory migration activity observed in serum samples of trypanosome infected animals implies the presence of mediators of cellular immunity. values of migration indices express reciprocal events of inhibitory and stimulating events in infected animals. this study allowed to follow at least some aspect ... | 1989 | 2618206 |
| cerebral trypanosomiasis in naturally-infected cattle in the lambwe valley, south nyanza, kenya. | surveys in zebu cattle in the lambwe valley in 1980 indicated that many (up to 70%) were infected with trypanosomes. the predominant parasite was trypanosoma brucei sspl followed by t. congolense. cerebrospinal fluid (csf) analysis showed a high proportion of animals with pleocytosis and elevated total csf protein. trypanosomes were detected in csf and signs of a central nervous system (cns) disease were observed. histopathological lesions in the cns were identical to those found in experimental ... | 1989 | 2619389 |
| effectiveness of wr 163577 against animal trypanosomes in goats and mice. | a bisquinaldine, 1,6-bis-(6-amino-2-methyl-4-quinolylamino) hexane, was tested against trypanosoma brucei ssp. in goats and against t. brucei, t. congolense and t. vivax in mice. at doses of 25 and 100 mg kg-1, the drug protected goats for at least 90 days against blood challenge with t. brucei ssp. fifty to sixty per cent of goats challenged 180 days after treatment were protected, but all goats challenged 270 days after treatment became infected. in mice, bisquinaldine also had a marked effect ... | 1989 | 2619391 |
| effects of splenectomy on trypanosoma congolense infection in cattle. | the role of the spleen in cattle infected with trypanosoma congolense was studied by comparing levels of parasitaemia, blood cell values, and body weights of intact and splenectomized cattle. a total of 28 zebu x hereford steers were used in two separate experiments. seven animals were splenectomized at least four weeks prior to infection and two others were splenectomized 128 days after infection. splenectomized animals were compared to 12 intact infected animals and seven intact uninfected con ... | 1989 | 2619394 |
| trypanosoma congolense: erythrocyte indices, plasma iron turnover and effects of treatment in infected cattle. | early during the course of trypanosoma congolense infection in cattle decreases in pcv occurred and coincided with increases in both mcv and mch. the indices reached highest levels between eight and 12 weeks post-infection. by week 20 of infection mcv and mch had decreased to pre-infection levels even though a substantial anemia persisted. serum iron levels were elevated at eight weeks postinfection. (infected 271 mg dl-1 v. control 140 mg dl-1) but decreased to low levels in infected animals by ... | 1989 | 2619395 |
| detection of parasite peptidase in the plasma of heifers infected with trypanosoma congolense. | plasma samples from heifers infected with trypanosoma congolense were shown to contain a parasite peptidase. in some instances, trypanosome peptidase was detected in plasma samples taken from heifers for up to 14 days after infections had been successfully treated with diminazene aceturate (berenil). trypanosome peptidase was detected in plasma using starch gel electrophoresis and also by a dot blot assay in which a mcab, raised against the enzyme, was spotted onto nitrocellulose filters which w ... | 1989 | 2651915 |
| expression of trypanosoma congolense trypanothione reductase in escherichia coli: overproduction, purification, and characterization. | the cloned trypanothione reductase gene from trypanosoma congolense has been expressed in escherichia coli to a level of 1% of the soluble protein. this has allowed facile purification and initial characterization of the reductase, and it appears by all criteria to be a representative member of the trypanothione reductase family. most importantly, it shows the same exclusive substrate specificity for trypanothione over glutathione characteristic of other trypanothione reductases examined to date ... | 1989 | 2669965 |
| biomedical science and the third world. under the volcano. trypanothione reductase. | | 1989 | 2698087 |
| chemoprophylaxis of trypanosomiasis, due to trypanosoma (nannomonas) congolense, in rabbits using a slow release device containing homidium bromide. | the prophylactic activity of a subcutaneously implanted slow release device, containing homidium bromide, was assessed in rabbits, challenged with different stocks of t. congolense, and compared with the classical treatment of 1 mg homidium bromide/kg b.w. intramuscularly. the prophylactic activity of the intramuscular injection was less than a month, while the slow release device protected the rabbits against seven challenges with t. congolense during a period of more than 300 days. | 1989 | 2698124 |
| interference in the establishment of tsetse-transmitted trypanosoma congolense, t. brucei or t. vivax superinfections in goats already infected with t. congolense or t. vivax. | an interference phenomenon that delays superinfection with a trypanosome species different from that used for the initial infection has been found to occur in goats. following tsetse transmission of trypanosoma brucei to goats already infected with t. congolense, there was a delay in chancre development, as well as in the appearance of t. brucei and anti-t. brucei antibodies in the blood when compared to previously uninfected goats. however, there was no delay in the establishment of a tsetse-tr ... | 1989 | 2705284 |
| occurrence of human serum-resistant trypanosoma congolense in goats and sheep in nigeria. | an assessment of the role of dogs, goats and sheep as reservoir hosts of african trypanosomes infective for humans (sleeping sickness) was carried out in nigeria during a 2-year study period. twelve stocks of trypanosoma (trypanozoon) brucei, 10 stocks of trypanosoma congolense and 11 stocks of trypanosoma vivax were isolated from a total of 699 animals, comprising 286 sheep, 221 goats and 192 dogs. the potential infectivity of the isolates for man was tested in vitro using the blood incubation ... | 1989 | 2741299 |
| comparative trypanotolerance of the small east african breed of goats from different localities to trypanosoma congolense infection. | differences in susceptibility of the small east african breed of goats to an experimental trypanosoma congolense infection were investigated. the goats were obtained from different areas of east africa, morogoro and arusha (tanzania), imbo and lambwe valley (kenya). morogoro goats were found to be more tolerant, followed by arusha, lambwe valley and imbo goats, in that order. the imbo goats had highest parasitaemia, more severe anaemia, marked weight losses and highest mortality rate. the morogo ... | 1989 | 2741304 |
| evidence for diploidy in metacyclic forms of african trypanosomes. | the dna contents of bloodstream form trypanosomes (life cycle stages circulating in the blood of the vertebrate host) of four african trypanosoma species and of metacyclic forms (the life cycle stage that is injected into the vertebrate by the tsetse fly during its bite) of the same four species were measured by cytofluorometry of individual cells or nuclei. the results showed unambiguously that the metacyclic forms cannot be considered to be products of meiosis containing only half of the dna o ... | 1989 | 2748597 |
| interference between drug-resistant and drug-sensitive stocks of trypanosoma congolense in goats. | a study was undertaken in goats to investigate the ability of two unrelated stocks of trypanosoma congolense, one of which is highly sensitive to isometamidium chloride and one which is drug-resistant, to become established in the presence of an existing infection with the other stock. the goats, which were initially infected with the sensitive strain and were then challenged with the resistant strain, were cured by treatment at 0.1 mg kg-1 isometamidium, indicating that the resistant stock did ... | 1989 | 2772408 |
| endocytosis by african trypanosomes. i. three-dimensional structure of the endocytic organelles in trypanosoma brucei and t. congolense. | african trypanosomes multiply rapidly during the course of infection obtaining nutrients from the host blood and other body fluids. the organelles involved in endocytosis were revealed ultrastructurally using horseradish peroxidase (hrp) and colloidal gold coupled to bovine transferrin (au-tf) or bovine serum albumin (au-bsa). at 0 degree c the markers bound to the cell surface and neither entered the flagellar pocket nor were internalized. upon warming to 37 degrees c, the markers were found in ... | 1989 | 2776775 |
| endocytosis by african trypanosomes. ii. occurrence in different life-cycle stages and intracellular sorting. | horseradish peroxidase (hrp) and colloidal gold-labeled proteins enter many of the endocytic organelles of bloodstream forms of trypanosoma brucei and t. congolense. however, the colloidal gold markers were excluded from substantial parts of the pathway that contained hrp. morphometric studies revealed that hrp entered organelles that accounted for approximately 5% of the total cell volume while transferrin-gold entered organelles that comprised approximately 2% of the total cell volume. in addi ... | 1989 | 2776776 |
| camel trypanosomiasis and its vectors in somalia. | blood samples from 3000 somali camels (camelus dromedarius) were examined for trypanosome infection. of these, 160 (5.33%) were infected with trypanosoma evansi, one (0.03%) with t. congolense and one (0.03%) with t. brucei. camel trypanosomiasis occurred in most areas of tabanid infestation throughout the country. the tabanids philoliche zonata and p. magretti are incriminated as the major vectors of the disease. | 1989 | 2781715 |
| the influence of trypanosoma congolense infection on the disposition kinetics of diminazene aceturate in the dog. | diminazene aceturate was administered intravenously at 3.5 mg/kg body weight to mongrel dogs before and after infection with trypanosoma congolense. plasma and urine were collected at varying intervals thereafter and analysed for the compound. the mean area under the concentration-time curve (auc) of diminazene in healthy dogs was 25.8 h.micrograms/ml but was significantly increased (p less than 0.05) to 35.7 h.micrograms/ml after infection with t. congolense. the distribution half-life was sign ... | 1989 | 2781721 |
| bovine trypanosomiasis in southern tanzania: investigation into the incidence of infection and duration of chemoprophylaxis. | before implementing chemoprophylaxis to control bovine trypanosomiasis it is essential to have epidemiological data upon which to base control regimes. a study was conducted under natural tsetse challenge with two groups each of 12 calves grazing their first season. group 1 received isometamidium treatments prophylactically at intervals during the rainy season and calves in group 2 were treated individually with diminazene as they become infected with trypanosomes. infections were first detected ... | 1989 | 2787560 |
| detection of trypanosoma congolense and trypanosoma brucei subspecies by dna amplification using the polymerase chain reaction. | the nuclear dna of trypanosoma congolense contains a family of highly conserved 369 base pair (bp) repeats. the sequences of three cloned copies of these repeats were determined. an unrelated family of 177 bp repeats has previously been shown to occur in the nuclear dna of trypanosoma brucei brucei (sloof et al. 1983a). oligonucleotides were synthesized which prime the specific amplification of each of these repetitive dnas by the polymerase chain reaction (pcr). amplification of 10% of the dna ... | 1989 | 2797872 |
| factors affecting duration and intensity of trypanosome infection of domestic animals. | domestic animals can become infected with several species of trypanosomes that are transmitted by tsetse, including trypanosoma congolense, t. vivax, t. brucei, t. simiae, t. rhodesiense and t. gambiense. the intensity and duration of the resulting parasitaemia are affected by the parasite, the host and detection methods. techniques currently used to detect parasites range in sensitivity from one to 10(5) organisms per ml. at the same time, parasite kinetics vary greatly both within and between ... | 1989 | 2802820 |
| calculating the basic reproductive rate ro when there are 2 or more pathogens. | some reasons why observed prevalences of the 3 major trypanosomes in cattle and livestock animals might not be independent are discussed. apart from genuine interactions between the infections, averaging over heterogeneous populations produces an apparent correlation between pathogens. more subtly, chemotherapy and mortality both induce a positive correlation between pathogens. the calculation of the basic reproductive rate ro for one pathogen in the endemic presence of another is explained, and ... | 1989 | 2802830 |
| trypanosoma congolense: drug resistance during cyclical transmissions in tsetse flies and syringe passages in mice. | a drug-resistant trypanosoma congolense strain with predetermined curative doses (cd50 and cd90) of samorin at 13.9 +/- 1.02 and 20.3 +/- 1.13 mg/kg body weight, respectively, was cyclically transmitted through tsetse flies and by syringe passages in mice in the absence of drug pressure. the changing levels of drug sensitivity were determined after every 3rd cyclic and 5th syringe passage intervals. it was noted that when the strain was maintained in tsetse flies through 12 cyclical transmission ... | 1989 | 2806460 |
| mini-exon gene repeats of trypanosoma (nannomonas) congolense have internal repeats of 190 base pairs. | genomic dna hybridizations reveal that the mini-exon gene repeats of trypanosoma (nannomonas) congolense contain from one to greater than 20 internal tandem repeats of 190 base pairs (bp). the sequences of two mini-exon gene repeats were determined, one with three internal 190 bp repeats and one with a single 190 bp sequence. these internal repeats appear just after a very dc/dt-rich region, in the non-transcribed spacer regions between adjacent mini-exon transcription units. they do not occur i ... | 1987 | 2823133 |
| a repetitive deoxyribonucleic acid sequence distinguishes trypanosoma simiae from t. congolense. | the dominant repetitive deoxyribonucleic acid (dna) sequence in the genome of a clone of trypanosoma (nannomonas) simiae has been identified and cloned as a recombinant plasmid. the recombinant plasmid was used in hybridization analyses of dna samples obtained from various trypanosome species and subspecies. the results indicated that the t. simiae repetitive dna sequence hybridized with dna derived only from t. simiae; it did not hybridize with dna derived from clones or stocks of t. congolense ... | 1987 | 2827093 |
| in vitro cultivation of trypanosoma congolense: establishment of infective mammalian forms in continuous culture after isolation from the blood of infected mice. | bloodstream form trypomastigotes of four cloned stocks of trypanosoma congolense from west africa were successfully adapted to continuous in vitro culture at 28 degrees c using bovine aorta endothelial cell monolayers and eagle's minimum essential medium supplemented with 20% normal bovine serum or foetal calf serum. the trypanosomes maintained in vitro morphologically resembled bloodstream forms and remained infective for vertebrate hosts. they also induced local skin reactions in rabbits and w ... | 1985 | 2862772 |
| influence of the salmon mutant of glossina morsitans morsitans on the susceptibility to infection with trypanosoma congolense. | four phenotypes of a sex-linked, maternally influenced semi-lethal eye color mutant of glossina morsitans morsitans westwood were fed on trypanosoma congolense broden infected guinea pigs. infection rates were evaluated 25 days later by means of dissection. procyclic as well as mature infections were significantly more common among females with salmon-colored eyes (sal/sal) than among heterozygous (+/sal, phenotypically wild-type) females. a tendency was found for more mature infections among sa ... | 1985 | 2862776 |
| in vitro cultivation of trypanosoma congolense: the production of infective forms from metacyclic trypanosomes cultured on bovine endothelial cell monolayers. | after transfer to bovine endothelial cell monolayers cultured in eagle's minimal essential medium at 28 degrees c or 37 degrees c metacyclic trypanosomes of three cloned stocks of trypanosoma congolense became morphologically similar to parasites found in the bloodstream of the vertebrate host. the trypanosomes resumed division and grew in close association with the mammalian cells, which were essential for growth. these dividing infective forms had the ability to cause local skin reactions and ... | 1985 | 2862783 |
| the probability of tsetse acquiring trypanosome infection from single blood meal in different localities in kenya. | the probability of tsetse, glossina pallidipes, acquiring a trypanosome infection from a single blood meal was estimated in five localities on the kenya coast which were selected for differences in habitat and host availability. the probability that one blood meal contained infective trypanosoma congolense was 0.0077 in rural areas with domestic animals, 0.0019 in extensive areas of natural habitat with wild hosts and 0.0013 in an area with domestic animals under regular chemoprophylaxis. the re ... | 1985 | 2865875 |
| a preliminary comparison of trypanosoma simiae and t. congolense by isoenzyme electrophoresis. | trypanosoma simiae, although similar to t. congolense in morphology and mode of development in the tsetse vector, is regarded as a separate species mainly because it is highly pathogenic to the domestic pig and fails to infect rodents. to establish whether the two species are distinct biochemically, we compared by isoenzyme electrophoresis 2 isolates of t. simiae with 7 stocks of t. congolense, together with one of t. brucei. all isoenzyme patterns of the 6 enzymes examined differed in t. simiae ... | 1986 | 2872783 |
| [sensitivity of the card agglutination test (testryp caat) in porcine infection with trypanosoma (nannomonas) congolense in the people' republic of the congo]. | | 1986 | 2872859 |
| infectivity to cattle of metacyclic forms of trypanosoma (nannomonas) congolense propagated in vitro. i. development of localized skin reactions following intradermal inoculation. | skin reactions similar to those induced by tsetse infected with trypanosoma congolense were elicited in cattle at sites of intradermal inoculation of in vitro propagated parasites which morphologically resembled metacyclic trypanosomes. the time to detection of the reaction, the time to maximal size and the maximal size attained were dependent on the number of parasites inoculated, although it was possible to induce a skin reaction with as few as 20 trypanosomes. all cattle became infected with ... | 1986 | 2877547 |
| evaluation of sinefungin for the treatment of trypanosoma (nannomonas) congolense infections in goats. | caprine trypanosoma (n.) congolense infections were treated with sinefungin, an antifungal antibiotic nucleoside. single doses from 10 to 20 mg/kg bodyweight given intramuscularly were not curative for goats; single doses of 25 and 50 mg/kg were toxic, and caused death. five and 7.5 mg/kg administered twice daily over a three-day period, resulted in a cure in 2 animals, while 2 others relapsed. all animals relapsed when given a single daily dose of 5 or 7.5 mg/kg for 4 consecutive days. when suc ... | 1986 | 2878488 |
| identification and selection of cattle naturally resistant to african trypanosomiasis. | cattle were exposed to natural trypanosome challenge in an area of high glossina density (samandéni, burkina faso) for various periods of time during 1982, 1983, 1984 and 1985. all of 30 zebu proved to be sensitive to trypanosomiasis i.e. they died or were treated in extremis in 10 +/- 4 weeks. twenty-one (31%) baoulé were as sensitive as the zebu while 47 (69%) were resistant i.e. they survived in good condition. twenty ndama/baoulé crosses, indigenous to samandéni were all resistant. weekly bl ... | 1987 | 2884840 |
| epidemiology of animal trypanosomiasis on a cattle ranch in kilifi, kenya. | a study of the epidemiology of animal trypanosomiasis was carried out on a 2500 ha cattle ranch, with a history of trypanosomiasis, in the coast province of kenya in 1982. the tsetse survey on the ranch revealed one breeding focus of glossina austeni in a thicket of approximately 50 ha. trypanosomes were detected in 20% of the 46 dissected tsetse. during the study period of 9 months, 0.8% of the 3315 samples collected from 2300 ayrshire x sahiwal crossbred cattle were found infected with trypano ... | 1987 | 2884841 |
| trypanosoma (nannomonas) congolense: properties of hexokinase and phosphofructokinase from cultured procyclic trypomastigotes and bloodstream forms. | the distribution and kinetics of two key glycolytic enzymes hexokinase (hk) and phosphofructokinase (pfk) were studied in animal-infective bloodstream forms (haematozoic trypomastigotes) and uninfective procyclic forms (insect trypomastigotes) of trypanosoma congolense. the results show that in both forms of t. congolense hk and pfk are particulate and are probably localized in a membrane-delimited organelle, the glycosome. hexokinases of bloodstream and procyclic forms of t. congolense are kine ... | 1987 | 2892364 |
| trypanosoma congolense: differentiation to metacyclic trypanosomes in culture depends on the concentration of glutamine or proline. | the effect of glutamine on the number of metacyclic trypanosomes produced in insect form cultures of trypanosoma congolense treu 1457 was investigated. when cultured in the absence of glutamine, trypanosomes did not develop to metacyclic forms. while metacyclics were produced in all cultures maintained with glutamine in the concentration range 2-20 mm, optimum numbers were obtained between 4 and 12 mm glutamine. this pattern was constant in flasks cultured for over two months. the substitution o ... | 1987 | 2892365 |
| dose and stage dependency for the development of local skin reactions caused by trypanosoma congolense in goats. | intradermal inoculation of metacyclic forms of trypanosoma congolense propagated in vitro caused skin reactions in goats similar to the local skin reaction (chancre) induced by the bite of an infected tsetse fly. the onset, size and duration of these local skin reactions were dose-dependent. whereas one cultured metacyclic t. congolense was sufficient to cause a local skin reaction in a goat, over 10(7) bloodstream forms of t. congolense were necessary to elicit a detectable skin reaction and wh ... | 1987 | 2892366 |
| high density lipoprotein levels in the serum of trypanosensitive and trypanoresistant cattle. changes during trypanosoma congolense infection. | nonpermissiveness to trypanosome infection has been correlated in some instances with the presence of toxic serum factors, e.g. high density lipoproteins (hdl) of human serum can lyse t.b. brucei. the present study examines the possibility of a role for such factors in west african cattle that are resistant to trypanosomiasis. cattle used in this study were previously selected as resistant or sensitive to trypanosomiasis under heavy natural glossina challenge. - a comparison of the direct effect ... | 1987 | 2892367 |
| the effect of the trypanocidal drugs berenil and samorin on infections of glossina morsitans centralis by trypanosoma congolense. | | 1987 | 2892374 |
| adaptation of trypanosoma congolense stocks to in vitro culture does not change their sensitivity to isometamidium. | | 1987 | 2892376 |
| selection for drug resistance in trypanosoma congolense during cyclic transmissions through glossina morsitans morsitans and drug treated rabbits. | a drug-sensitive trypanosoma congolense (il 1180 strain), with a known cd50 and cd90 (doses required to cure 50 and 90% of the infected animals) was cyclically passaged through tsetse flies. the infected flies were then fed on rabbits which received weekly prophylactic treatment of samorin. it was observed that the infections arising from flies maintained for over 60 days on drug-treated rabbits required higher curative doses to achieve a 50 and 90% cure. the results of this work suggest that a ... | 1988 | 2896442 |
| nuclear dna content of trypanosoma congolense. | we have measured the nuclear dna content of the major life cycle stages of trypanosoma congolense, in two clones of geographically distant origin. we find that nuclear dna content in epimastigote, mammalian blood-stream and metacyclic forms is constant and that the nuclear dna contents of the two clones were 0.1 pg and 0.09 pg, respectively. | 1988 | 2896443 |
| assessment of sensitivity of trypanosoma congolense to isometamidium chloride: a comparison of tests using cattle and mice. | the sensitivities of 3 strains of trypanosoma congolense to isometamidium chloride (samorin) were determined in mice and cattle, with the objective of evaluating sensitivity testing in mice as a means of predicting curative doses in cattle. comparison of mouse effective dose 80% (ed80) or curative dose 80% (cd80) values with cattle minimum curative dose (mcd) values demonstrated a wide variation between trypanosome strains. although a mouse test may give a broad indication of the sensitivity of ... | 1988 | 2901202 |
| trypanosome-induced ovarian dysfunction. evidence of higher residual fertility in trypanotolerant small east african goats. | changes in the length of oestrous cycles, plasma progesterone and oestradiol-17 beta levels were monitored for 6 months in trypanosoma congolense-infected normocyclic small east african goats obtained from three tsetse-endemic areas and one tsetse-free area of east africa. irregular oestrous cycles were observed in all infected goats, before cessation at the second cycle post-infection in the more susceptible and fourth cycle in the more resistant goat groups. a significant decline in the proges ... | 1988 | 2903624 |
| berenil (diminazene aceturate)-resistant trypanosoma congolense in cattle under natural tsetse challenge at kibaha, tanzania. | twenty-nine cattle, naturally infected with trypanosoma congolense kibaha, were subjected to chemotherapy with diminazene aceturate (berenil, hoechst) at 3.5 to 14.0 mg/kg. fourteen animals recovered while six were refractory to treatment at 7.0 to 14.0 mg/kg. further treatment of the berenil-resistant isolates with isometamidium chloride (samorin, may and baker) at 1.0 mg/kg, effected cure. corresponding chemotherapeutic trials in mice showed that the isolates were resistant to diminazene acetu ... | 1988 | 2903625 |
| [the use of sentinel animals for the evaluation of the control of vectors of sleeping sickness: preliminary reports at a congolese site]. | a large-scale control trial against glossina palpalis palpalis was carried out in the congo using a new trapping technique. in the same way a test related to the experimental utilization of sentinel animals was performed, concurrently to the classical epidemiological and entomological evaluation. 564 domestic animals (pigs, sheep, goats) were examined parasitologically (wet blood films, woo/hct) and serologically (testryps catt) in six villages. when a drastic reduction of tsetse populations was ... | 1988 | 2907260 |
| glycosyl-sn-1,2-dimyristylphosphatidylinositol is the membrane anchor for trypanosoma equiperdum and t. (nannomonas) congolense variant surface glycoproteins. | we have analysed the structures of the trypanosoma (nannomonas) congolense and t. equiperdum variant surface glycoprotein (vsg) membrane anchors. myristic acid uptake, phospholipase treatment, and nitrous acid deamination showed that, for each species, the anchor is glycosyl-sn-1,2-dimyristylphosphatidylinositol, as has been previously described for t. brucei. osmotic lysis of these trypanosomes resulted in the release of soluble vsg, lacking fatty acid. in both species and in t. evansi, an endo ... | 1987 | 2957588 |
| suppressive action of samorin on the cyclical development of pathogenic trypanosomes in glossina morsitans centralis. | male glossina sexually sterilized by gamma-irradiation are as efficient vectors of trypanosomiasis as fertile males. an attempt was made, using isometamidium chloride (samorin), to interfere with the cyclical development of trypanosomes in sterile males, destined for use in the sterile insect release (sir) method of tsetse eradication. the infection rate with mature trypanosoma congolense broden was effectively reduced in sterile male glossina morsitans centralis machado, when the flies were fed ... | 1987 | 2979543 |
| comparative study on the infection rates of different laboratory strains of glossina species by trypanosoma congolense. | teneral glossina morsitans centralis machado, g.austeni newstead, g.palpalis palpalis robineau-desvoidy, g.p.gambiensis vanderplank, g.fuscipes fuscipes newstead, g.tachinoides westwood and g.brevipalpis newstead, from laboratory-bred colonies, were fed at the same time on the flanks of ten goats infected with trypanosoma congolense broden isolated in tanzania or in nigeria. the seven tsetse species were infected over the range 0.3-49.2%. survival of both t.congolense isolates was best in g.m.ce ... | 1988 | 2980181 |
| kinetoplast dna from trypanosoma vivax and t. congolense. | we have analysed kinetoplast dna (kdna) of the african trypanosomes trypanosoma vivax and t. congolense. the maxi-circles from these organisms resemble those of t. brucei in size, but only to a limited extent in sequence as judged from restriction enzyme digests and dna x dna hybridization. the kdna networks of t. vivax have three distinguishing features: they contain the highest maxi-circle concentration of any kdna (at least twice that of t. brucei); they contain the smallest mini-circles (465 ... | 1985 | 2989683 |
| evidence for genetic diversity in trypanosoma (nannomonas) congolense. | genetic proximity between two karyotypic groups of trypanosoma congolense was investigated using as hybridization probes: total genomic dna, a 35 nucleotide long synthetic oligonucleotide, and non-variant antigen type (non-vat) specific complementary dnas. the phylogenetic relationship between trypanosoma brucei and t. evansi, both of which are accepted species in the subgenus trypanozoon, was used as a reference to assess the phylogenetic proximity of the two groups of t. congolense. results in ... | 1986 | 3024094 |
| sequences of two kinetoplast minicircle dnas of trypanosoma (nannomonas) congolense. | random minicircle dna molecules were released from isolated kinetoplast network dna of trypanosoma congolense by bamhi digestion and cloned into plasmid puc19. the sequences of two cloned minicircles (958 bp and 964 bp) were determined. both minicircles contain the 13 bp sequence, 5'-ggggttggtgtaa-3', thought to be the replication origin of minicircles in other trypanosomatids. the two minicircles have extensive homology in the 120 bp preceeding, and the 20 bp following, this 13-mer but only sca ... | 1987 | 3041215 |
| [chancre: an old-fashioned concept or a modern solution for sleeping sickness?]. | a brief introduction on trypanosomiasis in ruminants and an explanation of the term chancre are followed by a discussion of a number of findings on the early pathogenesis of the disease. this study formed part of the requirements in obtaining a doctorate in veterinary medicine. | 1988 | 3051513 |
| trypanosoma congolense: interactions between trypanosomes expressing different metacyclic variable antigen types in vitro and in vivo. | in trypanosome congolense, the surface antigens expressed by cultured metacyclic forms are a limited and serodeme-specific subset of variable antigen types (vats). experiments were carried out in mammalian-form (mf) cultures, comprising dividing trypanosomes which express metacyclic vats (m-vats) maintained in vitro with a mammalian cell feeder layer, or in mice following infection with cultured metacyclic populations. selective neutralization experiments were performed by incubating populations ... | 1988 | 3059264 |
| the alternative pathway of complement in sheep during the course of infection with trypanosoma congolense and after berenil treatment. | experimental t. congolense infections in sheep resulted in a striking decrease in parameters of the alternative complement pathway (acp), ie. factor b, c3 and haemolytic complement activity (ha) initiated via the acp. the levels of factor b, c3 and ha declined before, during and after the first wave of parasitemia which reached a peak at day 8. levels of 20 to 25% of normal values (factor b) and 20% (c3, ha) persisted throughout the course of the infection. after berenil treatment, when no paras ... | 1986 | 3088536 |
| surface carbohydrates of procyclic forms of african trypanosomes studied using fluorescence activated cell sorter analysis and agglutination with lectins. | living culture form procyclics of trypanosoma brucei brucei, t.b. rhodesiense, t.b. gambiense, t. congolense and t. simiae were tested for binding of eight different lectins. the binding of fluorescein isothiocyanate (fitc)-conjugated lectins was measured using a fluorescence activated cell sorter (facs) and by agglutination with unlabelled lectins. five of the lectins failed to bind to any of the procyclic organisms in both tests. all parasites bound concanavalin a (con a) and all t.b. brucei, ... | 1987 | 3106807 |
| chemotherapy of trypanosomiasis: the use of guanylhydrazone compounds in the treatment of experimental murine trypanosomiasis. | the efficacy of 1,3,5-triacetylbenzene tris(guanylhydrazone) trihydrochloride i.e. [(tbg)] in the treatment of early and late stage infections of trypanosoma brucei in mice was investigated. successful treatment on day 3 after infection could be achieved by doses of 2 x 2.5 mg kg-1. if treatment was delayed to 21 days after infection then the mice had to be given either suramin (1 x 20 mg kg-1) or difluoromethyl-ornithine (dfmo) 2% solution for 14 days in addition to either 15 mg kg-1 (tbg) dail ... | 1987 | 3124253 |
| [effects of sublethal doses of deltamethrin on the pair glossina morsitans morsitans-trypanosoma (nannomonas) congolense]. | the presence of trypanosoma in glossina morsitans morsitans induced a decrease in the physiological activity which is expressed in particular by a statistically higher mortality rate of infected flies. a similar effect appears with sublethal doses of deltamethrin either in infected or non infected insects. a cumulative activity of both effects was also observed in infected and treated flies. sublethal doses of the pyrethroid compound showed a delay in feeding, abortions and larval clampings. mor ... | 1988 | 3142654 |
| involvement of suppressor cells induced with membrane fractions of trypanosomes in immunosuppression of trypanosomiasis. | we showed that infection with trypanosoma congolense in mice led to suppression of listeria-induced delayed type hypersensitivity (dth). mice were pre-treated with irradiated t. evansi, which caused rapid and effective suppression of dth. a membrane fraction obtained by homogenizing t. evansi variant in a hypotonic buffer solution and centrifuging it at 150,000g produced suppression of listeria-induced dth when injected i.p. into mice as early as 1 day before listeria immunization. furthermore, ... | 1985 | 3158865 |
| trypanothione reductase of trypanosoma congolense: gene isolation, primary sequence determination, and comparison to glutathione reductase. | the gene encoding trypanothione reductase, the redox disulfide-containing flavoenzyme that is unique to the parasitic trypanosomatids (shames et al., 1986), has been isolated from the cattle pathogen trypanosoma congolense. library screening was carried out with inosine-containing oligonucleotide probes encoding sequences determined from two active site peptides isolated from the purified crithidia fasciculata enzyme. the nucleotide sequence of the gene was determined according to the dideoxy ch ... | 1988 | 3167026 |
| the effects of trypanosoma congolense infection on the oestrous cycle of the boran cow. | | 1988 | 3167553 |
| the effect of trypanosoma vivax and trypanosoma congolense infections on the reaction time and semen characteristics in the zebu bull. | | 1988 | 3167554 |
| formation of filopodia in trypanosoma congolense by crosslinking the variant surface antigen. | trypanosoma congolense was exposed to various substances binding to the variant surface antigen (vsg). all methods of crosslinking vsg molecules caused the rapid accumulation of ligands along the line of flagellar attachment and their shedding by formation of coat-covered vesicles and filopodia. this phenomenon was observed after treatment of the parasites with concanavalin a (con a), anti-vsg-igg plus protein a-gold, attachment of the cells to surfaces coated with poly-l-lysine and con a and to ... | 1988 | 3171247 |
| endocytosis and intracellular occurrence of the variant surface glycoprotein in trypanosoma congolense. | trypanosoma congolense bloodstream forms were examined for binding sites of polyclonal anti-variant surface glycoprotein (vsg) antibodies using immunoelectron microscopy. besides the surface, the antibodies labeled intracellular vesicles, the tubular membrane system, secondary lysosomes, and the digestive vacuole. protein a gold (pag), peroxidase gold (pog), anti-vsg antibodies preincubated with pag, ferritin, concanavalin a-ferritin, and microperoxidase were examined for their suitability as en ... | 1988 | 3171248 |
| the chromosome profiles of trypanosoma congolense isolates from kilifi, kenya and their relationship to serodeme identity. | chromosomal dna from 117 trypanosoma congolense clones from 54 stocks, isolated from cattle introduced onto a ranch in kilifi in the coastal area of kenya, was fractionated by the orthogonal field alternation gel electrophoresis technique. the technique resolved chromosomes in the size range of 100 kb-1 mb. the chromosome profile for cloned trypanosome populations was relatively stable with regard to number and size of the chromosome bands following transmission in mice, cattle, goats or tsetse ... | 1988 | 3173429 |
| species-specific dna probes for the identification of african trypanosomes in tsetse flies. | we have obtained 5 specific dna probes for african trypanosomes of the subgenera trypanozoon and nannomonas. each probe consists of one repeat unit of the major repetitive dna (satellite dna) of each species or intra-specific group. one probe hybridized with all members of subgenus trypanozoon (except t. equiperdum which was not tested). in subgenus nannomonas, one probe recognized t. simiae, but 3 probes were needed to identify all stocks of t. congolense available. each of the 3 latter probes ... | 1988 | 3174239 |
| [localization of trypanosoma (nannomonas) congolense broden, 1904 (kinetoplastida, trypanosomatidae) in the proboscis of glossina morsitans morsitans westwood, 1850 (diptera, glossinidae)]. | transverse sections of the proboscis of g. m. morsitans infected with t. (n.) congolense initiated after a single infective blood meal were studied. trypanosomes were located in the lateral, dorso-ventral and latero-ventral regions of the food canal. parasites were also found around the whole of the circumference of the canal. such localizations influence the transmission of trypanosomes and the epidemiology of trypanosomiasis. | 1988 | 3190120 |
| [trypanosoma (nannomonas) congolese broden, 1904 (kinetoplastida, trypanosomatidae) in epithelial cells of the anterior segment of the midgut of glossina morsitans morsitans westwood, 1850 (diptera, glossinidae)]. | | 1988 | 3217562 |
| pyrethroid impregnated ear tags in trypanosomiasis control. | | 1988 | 3238775 |
| some concepts of the interaction of trypanosoma (nannomonas) congolense and glossina pallidipes. | light and electron microscope investigations were carried out on the infection with trypanosoma (nannomonas) congolense of laboratory-reared tsetse flies glossina pallidipes. trypanosomes became entombed in the peritrophic membrane (pm) to form intraperitrophic cavities which were more electron-translucent than the amorphous layer of the pm. a hypothesis is suggested that after migration anteriorly in the ectoperitrophic space, the trypanosomes become enmeshed in the pm during its formation in t ... | 1988 | 3250337 |
| drug resistance in recent isolates of trypanosoma brucei and trypanosoma congolense. | | 1988 | 3253857 |
| quantitative correlation of parasitological and serological techniques for the diagnosis of trypanosoma congolense infection in cattle. | a comparison was made between serological and parasitological techniques for the diagnosis of bovine trypanosomiasis in zambia. overall sero-prevalence rates as determined by ifat and elisa were respectively 2.7-fold and 2.9-fold greater then the percentage of samples found positive with the dark ground/phase contrast buffy coat technique (dg). the results obtained by the two serological techniques were found to be closely correlated (94.2%) agreement) and titres obtained by elisa tended to be s ... | 1988 | 3287755 |
| characterization of trypanosoma congolense serodemes in stocks isolated from cattle introduced onto a ranch in kilifi, kenya. | a herd of 20 cattle was introduced on a ranch in kilifi, coast province of kenya, where they were in contact with glossina austeni for 6 months. in total, 65 trypanosome isolates were made from these animals. examination of the isolates revealed that 61 were trypanosoma congolense and 4 were t. theileri. out of the 61 t. congolense isolates, 55 were successfully passaged and cloned in mice to provide trypanosome populations for further analyses. the stocks and their clones were inoculated into g ... | 1987 | 3295687 |
| a new method for fixation and preservation of trypanosomal antigens for use in the indirect immunofluorescence antibody test for diagnosis of bovine trypanosomiasis. | a new method for fixation of trypanosomes for use in the indirect immunofluorescent antibody test (ifat) is described. the method involves fixation of live trypanosomes, in suspension, using a mixture of 80% cold acetone and 0.25% formalin in saline. the fixed trypanosomes were stored in suspension at -60 degrees c, 4 degrees c or at room temperature for at least one year without loss of antigenicity. using trypanosomes prepared this way as antigens in ifat, species-specific antibodies were dete ... | 1987 | 3299658 |
| monoclonal antibodies that distinguish trypanosoma congolense, t. vivax and t. brucei. | monoclonal antibodies (moabs) were derived against in-vitro-propagated procyclic forms of trypanosoma congolense, t. vivax, t. brucei brucei and t.b. rhodesiense in order to identify antigens for use in immunodiagnosis of african trypanosomiasis. the antibodies have been tested against procyclic and bloodstream form trypanosomes of 13 t. congolense, six t. vivax six t.b. brucei, four t.b. rhodesiense, five t.b. gambiense and three t. simiae isolates from different geographical areas by indirect ... | 1987 | 3306569 |
| enhanced resistance of highly susceptible balb/c mice to infection with trypanosoma congolense after infection and cure. | balb/c and c57bl/6 mice were cured with berenil after infection with cloned organisms of trypanosoma congolense and challenged with homologous or heterologous variants. the mice were fully protected against infection with 10(3) but not 10(5) organisms of the homologous variant. normal balb/c mice infected with 10(5) organisms developed uncontrolled parasitemia and had a mean survival time of 8.4 days. challenge of drug-cured balb/c mice with 10(5) organisms of the homologous variant established ... | 1987 | 3309242 |
| purification of african trypanosomes can cause biochemical changes in the parasites. | bloodstream forms of african trypanosomes are routinely purified from blood components by a combination of centrifugation and chromatography on deae cellulose at ph 8.0. here we report that the nonphysiological conditions used for deae chromatography of the parasites result in changes in the atp levels of the trypanosomes and an enhanced release from the parasites of proteins such as variable surface glycoprotein, peptidase, and phospholipase. some of these changes can be reduced by the addition ... | 1987 | 3323477 |
| sheep trypanosomiasis in somalia. | | 1988 | 3354058 |
| a model of tsetse-transmitted animal trypanosomiasis. | the data needed to develop analytical models of trypanosomiasis transmission have become available only recently. by making some simplifying assumptions, models of the dynamics of the disease in vector, cattle and wild mammal populations can be constructed in order to determine criteria for successful disease control by mass and targetted chemotherapy, and by vector control. the heterogeneity in transmission due to tsetse fly feeding preferences and the variability of immunological characteristi ... | 1988 | 3362578 |
| structure and transcription of the actin gene of trypanosoma brucei. | in trypanosoma brucei, the actin gene is present in a cluster of two, three, or four tandemly linked copies, depending on the strain. each cluster seems to exist in two allelic versions, as suggested by the polymorphism of both gene number and restriction fragment length in the dna from cloned trypanosomes. the amplification of the gene copy number probably occurs through unequal sister chromatid exchange. the chromosomes harboring the actin genes belong to the large size class. the coding seque ... | 1988 | 3386635 |
| effect of chronic experimental trypanosoma congolense infection on the ovaries, pituitary, thyroid and adrenal glands in female goats. | changes in the ovaries, pituitary, thyroid and adrenal glands in small east african normally cycling female goats chronically infected with trypanosoma congolense are described. marked fibrosis of the ovaries, a decrease in the number of primordial and primary follicles and atresia of growing follicles at the tertiary stage resulting in lack of corpora lutea were observed. the pituitary glands revealed reduced degranulation of the basophils and slight hypertrophy of the acidophils. the thyroids ... | 1988 | 3387663 |
| development of trypanosoma congolense, t vivax and t brucei in the skin reaction induced in goats by infected glossina morsitans centralis: a light and electron microscopical study. | the development and distribution of trypanosoma congolense, t vivax and t brucei in the skin of goats was examined after the animals were bitten by infected glossina morsitans centralis. following the tsetse bite, the trypanosomes in the skin multiplied, reaching maximum numbers when the skin reaction (chancre) of the host attained its maximum size. in goats infected with t vivax and t brucei, trypanosomes were observed circulating in the blood before the peak of the chancre, while in t congolen ... | 1988 | 3387665 |
| the role of lectins and trypanosome genotype in the maturation of midgut infections in glossina morsitans. | feeding d + glucosamine to glossina morsitans throughout their life significantly reduced the proportions of midgut infections which developed into mature infections with three different stocks of trypanosoma congolense. in one stock of t. congolense, maturation was completely blocked by this carbohydrate, which is known to specifically inhibit tsetse midgut lectin activity. similar experiments with t. brucei showed that d + glucosamine also inhibited maturation and, when combined with results f ... | 1988 | 3387828 |
| factors influencing the duration of isometamidium chloride (samorin) prophylaxis against experimental challenge with metacyclic forms of trypanosoma congolense. | the duration of a single isometamidium chloride (samorin) prophylactic treatment against trypanosoma congolense ilnat. 3.1 and t. congolense il 285 was examined in 24 boran steers with regard to (1) the dose of drug, (2) the level of metacyclic challenge and (3) the influence of infection with an unrelated serodeme at the time of treatment. the cattle were repeatedly challenged at monthly intervals between 2 and 7 months following treatment, either by five infected glossina morsitans centralis o ... | 1988 | 3388736 |
| depression of ovarian function and plasma progesterone and estradiol-17 beta in female goats chronically infected with trypanosoma congolense. | adult normocyclic female goats experimentally infected with trypanosoma congolense developed irregular and shorter estrous cycles before complete cessation at the fourth cycle post-infection. this was followed within a month by a decline in the mean plasma progesterone and estradiol-17 beta levels. the peak luteal progesterone as well as pre-ovulatory estradiol-17 beta level declined progressively from the second to the fourth cycle post-infection. the ovaries became atretic with reduced numbers ... | 1988 | 3389040 |
| immune responses of trypanoresistant and trypanosusceptible cattle after cyclic infection with trypanosoma congolense. | to study the mechanisms by which certain west african taurine cattle are able to resist trypanosomiasis, the disease course and several immune parameters were examined in eleven baoulé and five zebu cattle after infection with tsetse-transmitted t. congolense (clone 1180 of stock serengeti/71/stib/212). all animals showed a similar onset of parasitemia but subsequently a continuum of disease was observed ranging from four baoulé which were mildly susceptible (controlled parasitemia by week 10 po ... | 1988 | 3394256 |
| prevalence of trypanosomiasis in cattle in south-west zambia. | a trypanosomiasis survey was conducted in south-west zambia. from a total of 3,346 cattle sampled 342 cattle showed a positive trypanosomiasis parasitaemia. during the survey trypanosome species and pcv values were also recorded. with simple statistical analysis populations with higher and lower prevalence rates were differentiated. the results indicated that the kwando river basin tsetse fly belt and the kafue river basin tsetse fly belt infested a larger area than originally assumed and that a ... | 1988 | 3400114 |
| ro 15-0216: a nitroimidazole compound active in vitro against human and animal pathogenic african trypanosomes. | in vitro systems for the continuous cultivation of trypanosoma brucei brucei, t. b. gambiense, t. b. rhodesiense, t. congolense and t. vivax were used to determine the antitrypanosomal activity of the 2-substituted nitroimidazole ro 15-0216. for all trypanosome species, the concentration which inhibited parasite growth by 50% (ic50 value) was established: 0.0957 microgram ml-1 (t. b. brucei tc221), 0.1327 microgram ml-1 (t. b. gambiense stib 754-a), 0.0450 microgram ml-1 (t. b. rhodesiense stib ... | 1988 | 3401068 |
| genetically discrete populations of trypanosoma congolense from livestock on the kenyan coast. | twenty-seven stocks of nannomonas trypanosomes isolated from livestock in 1982 on a ranch at kilifi on the kenyan coast were characterized by isoenzyme electrophoresis and by the abilities of the parasite's dna to hybridize to two repetitive sequence dna probes. all the kilifi stocks which were examined had isoenzyme patterns which were markedly different from the 75 patterns previously described from 78 stocks of trypanosoma congolense. on average only 15% of the enzyme bands present in the kil ... | 1988 | 3405633 |
| trypanosoma congolense: the distribution of enzymic variants in east and west africa. | a total of 114 stocks of trypanosoma congolense originating from kenya, uganda, tanzania, zambia and sudan, but including, for comparison, stocks from the gambia, liberia, ivory coast, nigeria and cameroun, were compared by isoenzyme electrophoresis for 6 enzymes. the zymodemes were grouped, both from a dendrogram and using a cladistic method, after calculating the dissimilarity, or distance, between profiles. previous observations are broadly confirmed, the zymodemes clustering separately accor ... | 1988 | 3405634 |
| the requirement for epimastigote attachment during division and metacyclogenesis in trypanosoma congolense. | in cultures of tsetse proboscis stages during the development of trypanosoma congolense, attached epimastigote forms multiply and give rise to free nondividing metacyclic trypanosomes. prevention of attachment by shaking the cultures or by providing a polypropylene substratum does not inhibit epimastigote division but does prevent the differentiation of metacyclics. we conclude that epimastigote attachment forms a necessary part of the program of metacyclic development. | 1988 | 3413039 |