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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 ...19882896442
cultivation of the life cycle stages of trypanosoma brucei sspp.a culture system was devised for the production of the various stages in the developmental cycle of trypanosoma brucei brucei and t. b. rhodesiense. the bloodstream forms were grown at 37 degrees c on a feeder layer of fibroblasts from embryos of microtus montanus or cd-1 mice in hepes-buffered minimum essential medium with earle's salts, supplemented with 15% heat-inactivated rabbit serum. when they were transferred to hepes-buffered cunningham's medium and incubated at 27 degrees c, they trans ...19882896444
suppression of cyclical development of trypanosoma brucei brucei in glossina morsitans centralis by an anti-procyclics monoclonal antibody.five hundred and sixty teneral male glossina morsitans centralis were fed, at the height of parasitaemia, on a goat infected with trypanosoma brucei brucei. thereafter, the tsetse were divided into 4 equal groups. group i was fed in vitro once weekly for 4 weeks and group ii twice weekly for 4 weeks on fresh defibrinated ox blood containing 2 mg/ml purified monoclonal antibody against t. b. brucei procyclics, while group iii was fed twice a week for 4 weeks on blood containing 2 mg/ml anti-t. vi ...19882901200
infection rates in sterile males of morsitans, palpalis and fusca groups glossina for pathogenic trypanosoma species from east and west africa.infection rates in sterile male glossina morsitans centralis, g. austeni, g. palpalis palpalis, g.p. gambiensis, g. fuscipes fuscipes, g. tachinoides and g. brevipalpis for trypanosoma vivax, t. congolense and t. brucei isolated from east and west africa, were studied. five groups of the sterile males, together with the five groups of sexually fertile males, of each of the respective species and subspecies were allowed to feed for 24 days on a boran calf or goats infected with t. vivax or t. con ...19882901201
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 ...19872979543
a behavioural bioassay to identify attractive odours for glossinidae.1. a behavioural bioassay, based on antennal movement responses, was developed using glossina morsitans morsitans westwood for screening chemical attractancy to tsetse. 2. chemicals found to be attractive to male tsetse were acetone, formaldehyde, methylethylketone, methylvinylketone, 1-octen-3-ol and pentanal but not acetophenone, hexanal, lactic acid or urea. 3. female tsetse also responded to all these chemicals in a similar fashion. overall responses of females were, however, less than those ...19872979547
juvenile hormone mimics as effective sterilants for the tsetse fly glossina morsitans morsitans.the development of puparia of glossina morsitans morsitans westwood was disrupted by topical applications of the juvenile hormone mimics s-methoprene (the resolved enantiomer of 11-methoxy-3,7,11-trimethyl-2,4-dodecadienoic acid 1-methyl ester) (zoecon), s21149 (propionaldoxime-0-4-phenoxyphenoxyethylether) (sumitomo), or s31183 (2-[1-methyl-2-(4-phenoxyphenoxy)ethoxy]pyridine) (sumitomo) dissolved in acetone. puparia so treated during the first 4 days of life suffered developmental abnormalitie ...19882980157
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 ...19882980181
survival and reproductive performance of female glossina morsitans morsitans when maintained on the blood of different species of wild mammals.a study was carried out to determine the effect on the reproductive performance of female glossina morsitans morsitans westwood when allowed to feed, in vitro, for 63 days on fresh defibrinated blood of buffalo, bushbuck, cattle, eland, oryx, warthog, waterbuck or wildebeest. there were marginal differences in the survival and reproductive performance between eight different groups of tsetse, 200 per group, when fed on the blood of these mammalian species. when allowed to feed for 14 consecutive ...19882980193
further analysis of intraspecific variation in trypanosoma brucei using restriction site polymorphisms in the maxi-circle of kinetoplast dna.we have compared the maxi-circle kinetoplast dna of 21 trypanosoma brucei sp. stocks by analysis of restriction sites for nine restriction endonucleases. the analysis shows most of these stocks to have a maxi-circle sequence similar to that of 11 previously analysed stocks, with a difference of less than 3% between any two stocks. however, seven stocks stand out from the rest with at least two sites lost or gained for six of the nine restriction enzymes used. these seven distinctive stocks fall ...19852985985
effect of theophylline on differentiation of trypanosoma brucei.differentiation of trypanosoma brucei in the mammal limits the degree of parasitemia and prepares the trypanosome for passage back into the tsetse fly. in an attempt to define the signals that control differentiation, we found that theophylline, in contrast to indomethacin, blocked differentiation, prolonged parasitemia, elevated prostaglandin and cyclic amp concentrations of rat plasma, and depressed intratrypanosomal cyclic amp. relatively nontoxic drugs that alter differentiation are powerful ...19852993168
[ecology of tsetse flies in the preforested area of the ivory coast. relation to human trypanosomiasis and possibilities for control].this paper gives the results of a tsetse fly research program in the preforested area of ivory coast. the main investigation tool was the challier-laveissière's biconical trap. the ecodistribution, resting and pupal sites of the principal tsetse species, g. palpalis, g. pallicera and g. nigrofusca were described in the t. b. gambiense sleeping sickness focus of vavoua. population dynamics, host preferences, activity cycles were compared between tsetse populations in plantations and village surro ...19852998259
tsetse fly rdna: an analysis of structure and sequence.a genomic library of glossina morsitans morsitans (tsetse fly) has been constructed in the phage vector embl 4 and a complete rdna unit isolated by using a d. melanogaster rdna clone as a probe. the overall organisation is typical of higher eukaryotes, including an intergenic spacer consisting of a subrepeating structure. atypically, however, the 45s precursor rna promoter was shown to lie within the last subrepeat by s1 mapping; i.e. the last subrepeat extends 90 bp into the ets. the sequence o ...19873029668
[house effect and family contamination in sleeping sickness: interpretative trial of the phenomenon. study of 3 congolese foci].a review is given of the different hypotheses concerning the concentration of trypanosomiasis cases at the house or family level: 1. mechanical transmission by haematophagous insects. 2. interrupted feeding of a tsetse fly with cyclic infection on different people. 3. family biological factor. these hypotheses are used as a introduction to an epidemiological field study in three congolese foci. whereas their distribution among village districts is random, patients are significantly aggregated at ...19883059954
biology of african trypanosomes in the tsetse fly.african trypanosomes present several features of interest to cell biologists. these include: a repressible single mitochondrion with a large mass of mitochondrial dna, the kinetoplast; a special organelle, the glycosome, which houses the enzymes of the glycolytic chain; a surface coat of variable glycoprotein which enables the parasite to evade the mammalian host's immune response; and a unique flagellum-to-host attachment mechanism associated with novel cytoskeletal elements. trypanosome develo ...19883067793
evolution of the secondary structures and compensatory mutations of the ribosomal rnas of drosophila melanogaster.this paper examines the effects of dna sequence evolution on rna secondary structures and compensatory mutations. models of the secondary structures of drosophila melanogaster 18s ribosomal rna (rrna) and of the complex between 2s, 5.8s, and 28s rrnas have been drawn on the basis of comparative and energetic criteria. the overall au richness of the d. melanogaster rrnas allows the resolution of some ambiguities in the structures of both large rrnas. comparison of the sequence of expansion segmen ...19883136295
[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 ...19883142654
[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.19883190120
loss of variable antigen during transformation of trypanosoma brucei rhodesiense from bloodstream to procyclic forms in the tsetse fly.a pleomorphic line of trypanosoma brucei rhodesiense expressing a single variable antigen was used to quantify the rate of loss of the surface coat from bloodstream forms transforming to procyclics in the tsetse fly, glossina morsitans, and in in vitro culture. loss of variable antigen occurred at similar rates in the crop and anterior portion of the midgut of tsetse flies and in in vitro culture, but in the posterior portion of the fly midgut it occurred 2-3 times faster. the posterior portion ...19883194363
[breeding of glossina morsitans submorsitans newstead, 1910 (diptera-glossinidae in the crta of bobo-dioulasso, burkina faso. i. adaptation of a wild strain to the laboratory breeding conditions on feeding hosts]. 19883194566
comparative study on the susceptibility of different glossina species to trypanosoma brucei brucei infection.teneral glossina morsitans centralis, g. austeni, g. palpalis palpalis, g. p. gambiensis, g. fuscipes fuscipes, g. tachinoides and g. brevipalpis from laboratory-bred colonies, were allowed to feed simultaneously for 34 days on the flanks of ten goats infected with trypanosoma brucei brucei isolated in tanzania or in nigeria, and then the tsetse were dissected. the seven tsetse species and subspecies showed salivary glands infections over the range of 0% to 40.4%. survival of the tanzanian and n ...19883194664
detection of antigens common to salivary glands and other tissues of tsetse fly, glossina palpalis palpalis (diptera: glossinidae).the study demonstrates the common antigens to salivary gland, fat body, mesenteron, thorax muscle, native whole body, and dried whole body homogenates of tsetse flies, g. palpalis palpalis. the possibilities of their origin and the role in hypersensitivity induction and its propagation are discussed.19883198018
[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)]. 19883217562
[comparison of the attractive power of zébu and baoulé cattle for glossina tachinoides westwood, 1850 and glossina morsitans submorsitans newstead, 1910 in sudano-guinean savanna, burkina faso]. 19883217566
the timing and frequency of hybrid formation in african trypanosomes during cyclical transmission.the frequency of hybrid formation between two trypanosoma brucei clones during cyclical transmission through glossina morsitans centralis was analyzed. in two independent experiments, teneral g. m. centralis were infected with an equal mixture of two t. brucei clones showing different homozygous isoenzyme patterns for isocitrate dehydrogenase (icd; e.c.1.1.1.42) and alkaline phosphatase (ap; e.c. 3.1.3.1). trypanosomes were cyclically transmitted to mice from 23 infective flies and the subsequen ...19883237678
field studies on animal trypanosomiasis in mozambique. i. effectiveness of the prophylactic drugs isometamidium chloride and pyrithidium bromide.the efficacy of the trypanocides samorin and prothidium to protect beef cattle in areas of different trypanosome challenge was studied in muabsa, mozambique during an 18 month period. the performance of two groups of 1.5- to 3-year old bulls was observed, the first group in an area of high tsetse density, the second in an area of low to medium tsetse density. glossina morsitans and g. pallidipes were present and their respective densities were determined using standard fly rounds, a mobile elect ...19883238772
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 ...19873306569
import of fructose bisphosphate aldolase into the glycosomes of trypanosoma brucei.the glycolytic enzymes of trypanosomatids are compartmentalized within peroxisome-like microbodies called glycosomes. fructose bisphosphate aldolase is synthesized on free polysomes and imported into glycosomes within 5 min. peptide mapping reveals no primary structural differences between the in vivo-synthesized protein and that made in vitro from a synthetic template. however, native aldolase from glycosomes is partially protease resistant, whereas the in vitro translation product is not. puls ...19873320052
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 ...19883362578
the humoral defense system in tsetse: differences in response due to age, sex and antigen types.inoculation of live escherichia coli into tsetse flies, glossina morsitans morsitans, stimulated a higher antibacterial immune response in females than in males. it increased with age in females from emergence to approximately 2 weeks and thereafter declined. in males, there was also a significant decrease in immune response with aging. inoculation of killed bacteria failed to stimulate antibacterial activity but stimulated a lysozyme response which was weaker than that stimulated by live bacter ...19883384155
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 ...19883387665
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 ...19883387828
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 ...19883388736
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 ...19883400114
[comparison of the longevity of tsetse flies (glossina morsitans morsitans westwood, 1850) infected with trypanosomes (trypanosoma nannomonas congolense broden, 1904) and uninfected tsetse flies].this preliminary note results from a comparative study on susceptibility to pyrethroid insecticides of tsetse flies infected and not with trypanosomes. trypanosoma infection increases the susceptibility to insecticides as previous study showed it (golder et al., 1982, 1984). moreover, infected control flies showed a significant lower longevity than uninfected ones.19883421645
cell adhesion in trypanosoma: in vitro studies of the interaction of trypanosoma vivax with immobilized organic dyes.certain bloodstream forms of trypanosoma vivax have been shown to attach to amicon matrex gel green a dye beads in a manner similar to the in vivo binding of t. vivax to the inner surface of the tsetse fly proboscis. we now report an in vitro assay for trypanosome-bead attachment and show that only the 9,10-anthraquinone portion of the dye molecule is involved in the binding of trypanosomes to beads and that bead-bound dyes with similar structures also support binding to differing degrees. the b ...19873430412
lectin mediated establishment of midgut infections of trypanosoma congolense and trypanosoma brucei in glossina morsitans.d+glucosamine, which has been shown in vitro to specifically inhibit tsetse midgut lectin activity, when fed to glossina morsitans morsitans with the infective feed significantly increased midgut infection rates of trypanosoma congolense and t. brucei rhodesiense. all flies infected with t.b. rhodesiense and maintained on a diet of blood with d+glucosamine throughout their lives developed midgut infections. midgut extracts from flies bred for refractoriness to infection with trypanosomes showed ...19873432950
failure of trypanosoma vivax to generate protective immunity in goats against transmission by glossina morsitans morsitans. 19873445345
evidence for haploidy in metacyclic forms of trypanosoma brucei.the parasitic flagellate trypanosoma brucei undergoes a series of morphologic and metabolic changes during its passage in the digestive organs of its insect vector, a glossina or tsetse fly. this morphogenesis ends by the differentiation, in the salivary gland of the fly, of the metacyclic form, which will be transmitted in the bloodstream of the mammalian host. on the basis of dna microfluorometric measurements, we propose that these metacyclic trypanosomes have a haploid amount of dna, compare ...19863461475
peripheral blood leucocytes subpopulation dynamics during trypanosoma congolense infection in boran and n'dama cattle: an analysis using monoclonal antibodies and flow cytometry.a panel of monoclonal antibodies (moab) with specificities for bovine leucocyte subsets were used in conjunction with routine haematological procedures to analyse sequential changes in peripheral blood leucocyte populations during the course of tsetse fly-transmitted trypanosoma congolense infection in trypanotolerant n'dama and trypanosusceptible boran cattle. subsequent to the first parasitaemic wave, the n'dama cattle maintained packed cell volumes (pcv) above 22 and lower levels of parasitae ...19873496577
effect of samorin administered to a bovine host on the survival and reproductive performance of female glossina morsitans centralis. 19873503652
procyclic tsetse fly midgut forms and culture forms of african trypanosomes share stage- and species-specific surface antigens identified by monoclonal antibodies.procyclic culture form (pcf) trypanosomes were established from a bloodstream form population of cloned trypanosoma brucei rhodesiense and were used to immunize mice for hybridoma production. indirect immunofluorescence was used to select 10 hybridomas which secreted antibodies that bound to the surface of homologous living pcf. the antibodies reacted with pcf of several clones of t.b. brucei, t.b. gambiense, and t.b. rhodesiense, but not with pcf of t. congolense or t. vivax, or with promastigo ...19863512712
analysis of trypanosome variable antigen types in cultures of metacyclic and mammalian forms of trypanosoma congolense.cultured metacyclic forms of trypanosoma congolense display a characteristic repertoire of metacyclic variable antigen types (m-vats) similar to that exhibited in vitro in the tsetse fly. there appeared to be no change in expression of m-vats in cultures of two stocks of t. congolense even after several passages, cryopreservation or long-term cultivation in vitro. metacyclic forms transformed into mammalian forms when transferred to cultures of bovine aorta endothelial cells and whilst one stock ...19863528995
differential protein synthesis during the life cycle of the protozoan parasite trypanosoma brucei.two-dimensional polyacrylamide gel electrophoresis has been used to analyze changes in protein content and protein synthesis in three stages of the life cycle of the protozoan parasite trypanosoma brucei. the stages examined were slender and stumpy mammalian bloodstream forms and procyclic forms, which are analogous to the tsetse fly midgut stage. two-dimensional gels of 35s-methionine-labeled proteins were examined by autoradiography to analyze newly synthesized protein, and gels were stained w ...19873572842
trypanosoma congolense: host responses following tsetse transmitted infection of kilifi isolates in goats.east african x galla goats, when infected with trypanosoma congolense isolates from the kilifi area of kenya by glossina morsitans centralis, did not develop the characteristic chancre reaction at the bite sites, whereas bites of tsetse infected with the cloned t. congolense il.1180 from serengeti, tanzania, resulted in chancres in the same goats. histological changes could not be observed in skin biopsies collected 8 or 9 days after infection with kilifi isolates. however, all goats became para ...19873582569
potential value of localized skin reactions (chancres) induced by trypanosoma congolense transmitted by glossina morsitans centralis for the analysis of metacyclic trypanosome populations.goats infected with trypanosoma congolense transmitted by glossina morsitans centralis and then treated with the trypanocidal drug diminazene aceturate are immune to tsetse-transmitted infection with a homologous, but not heterologous trypanosome clone. immune animals fail to develop localized skin reactions (chancres) and do not become infected, whereas on heterologous challenge chancres appear followed by parasitaemia. in this study, the feasibility of using chancre reactions to characterize s ...19873601446
[a new glossina from the congo: glossina (austenina) frezili sp. nov. (diptera: glossinidae)].the male and female genitalia of glossina frezili sp. nov., a new tsetse fly occurring in the mangrove forest of the congo and gabon are described. g. frezili is related to g. medicorum but clearly distinct from this species by its habitat and the morphology of the genitalia.19873629143
onset of expression of the variant surface glycoproteins of trypanosoma brucei in the tsetse fly studied using immunoelectron microscopy.the acquisition of the variant surface glycoprotein (variable antigen) coat by metacyclic stage trypanosoma brucei in the salivary glands of the tsetse fly, glossina morsitans, has been studied in situ by transmission and scanning electron microscopy using monoclonal antibodies raised against metacyclic variable antigen types and complexed with horseradish peroxidase or colloidal gold. the coat is acquired after binary fission has ceased but while the parasite is still attached to the gland epit ...19873654788
a novel arrangement of sequence elements surrounding the rdna promoter and its spacer duplications in tsetse species.variation in organization and sequence of the rdna of six species of tsetse fly (glossina) has been investigated. several novel tsetse-specific features have been uncovered. like many other species the spacer is composed of subrepeats, which in some species contain duplications of the true promoter at the spacer-ets boundary. in tsetse, however, the first 90 base-pairs of the external transcribed spacer (ets) (that is, +1 to +90 after transcription initiation) is the 3' end of the last subrepeat ...19873656412
use of species-specific dna probes for detection and identification of trypanosome infection in tsetse flies.species- and subspecies-specific trypanosome dna hybridization probes have been employed in the detection and identification of trypanosome infections in glossina morsitans centralis. several ways of sample preparation including the use of tsetse organ suspensions, proboscides and dissected midguts, as well as tsetse abdominal content touch-blots were explored. the results of hybridization of radio-isotope-labelled species-specific dna probes to tsetse samples indicated that it was possible to d ...19873670893
trypanosoma congolense: lack of correlation between the resistance of cattle subjected to experimental cyclic infection or to field challenge.twelve male cattle of the baoulé breed were exposed to natural trypanosome challenge in an area of high glossina density, to characterize them as trypanoresistant or trypanosensitive. weekly blood samples were taken for the determination of parasitemia and packed cell volume, as a measure of anemia. seven zebu cattle were also exposed to challenge at the same time. the zebu proved to be trypanosensitive with high parasitemia, pronounced anemia and died or were drug treated in extremis. five baou ...19873678447
therapeutic and prophylactic activity of isometamidium chloride in boran cattle against trypanosoma vivax transmitted by glossina morsitans centralis.ten boran steers were infected with trypanosoma vivax, transmitted by glossina morsitans centralis; five steers with a t vivax clone from nigeria and five with a t vivax clone from kenya. eleven days after infection all 10 animals were treated with 0.5 mg kg-1 isometamidium chloride. four steers infected with the nigerian t vivax and all five infected with the kenyan t vivax were completely cured. when different steers received a single prophylactic dose of 0.5 mg kg-1 isometamidium chloride and ...19873685643
culture form and tsetse fly midgut form procyclic trypanosoma brucei express common proteins.proteins expressed by culture form and tsetse fly midgut form procyclic trypanosomes were examined by polyacrylamide gel electrophoretic techniques. analysis of the proteins of the two forms of procyclic organisms was performed by comparison of autoradiographs of high resolution two-dimensional polyacrylamide gels prepared using [35s]methionine-labelled parasites. only eight spots were found to differ between autoradiographs of culture form and tsetse fly midgut form parasites. seven of these di ...19873696176
comparative study on the infection rates of different glossina species for east and west african trypanosoma vivax stocks.teneral male glossina morsitans centralis, g. austeni, g. palpalis palpalis, g. p. gambiensis, g. fuscipes fuscipes, g. tachinoides and g. brevipalpis were fed on the flanks of boran calves infected with trypanosoma vivax stock ilrad 2241 isolated from a cow in likoni, kenya; stock ilrad 2337 isolated from a cow in galana, kenya; stock ilrad 1392 isolated from a cow in nigeria; or, stock eatro 1721 isolated from g. m. submorsitans in nigeria. the tsetse were fed on the infected hosts for 24 days ...19873696778
species identification of blood-meals from tsetse flies (glossinidae): results 1979-1985.results from species identification of almost 6,000 tsetse fly blood-meals are reported. regarding glossina palpalis and g. pallidipes, it was shown that the preference of tsetse flies for certain host species differed according to the sampling area. consequently, results from blood-meal identification are to be interpreted with this point in view.19863704476
parasite kinetics and immune responses in efferent prefemoral lymph draining skin reactions induced by tsetse-transmitted trypanosoma congolense.localised skin reactions (chancres) occurred on the flanks of cattle at the sites of deposition by tsetse flies of metacyclic forms of trypanosoma congolense. marked enlargement of the draining prefemoral lymph nodes accompanied the development of the skin reactions. lymph from these nodes was collected through polyethylene cannulae inserted into the efferent lymphatics, and examined for trypanosomes, cells and antibody content. within 6-9 days after infected tsetse fly bite, trypanosomes were d ...19863705421
susceptibility and immune responses of zebu and taurine cattle of west africa to infection with trypanosoma congolense transmitted by glossina morsitans centralis.following tsetse-transmitted infection with trypanosoma congolense, major differences in development of localised skin reactions, the ability to control parasitaemia, the degree of anaemia and in antibody response to trypanosomes were found between the reputedly trypanotolerant breeds of cattle (n'dama, n'dama/baoule crosses, baoule) and the trypanosusceptible west african zebu. the local skin reactions that developed in the zebu were large and severe while those that occurred in the other breed ...19863716196
hybrid formation between african trypanosomes during cyclical transmission.trypanosomes of the species trypanosoma brucei reproduce primarily by binary fission, but the frequency of enzyme electrophoretic variants in natural populations of t. brucei has provided indirect evidence for the existence of a sexual cycle. these studies, coupled with studies of restriction fragment length polymorphisms of genes encoding glycolytic enzymes, have also provided evidence for t. brucei being diploid. here we report direct evidence of gene exchange between two different clones of t ...19863724860
extrachromosomal inheritance of susceptibility to trypanosome infection in tsetse flies. ii. susceptibility of selected lines of glossina morsitans morsitans to different stocks and species of trypanosome.two lines of glossina m. morsitans, selected for susceptibility and refractoriness to infection with a single stock of trypanosoma congolense, have now been shown to be susceptible or refractory to different stocks of t. congolense and, also, to different stocks of t. b. brucei and t. b. gambiense. the mean midgut infection rates of the susceptible line obtained in different experiments with t. congolense, t. b. brucei and t. b. gambiense were, respectively, 66%, 56% and 55%; the corresponding m ...19863729601
infectivity of trypanosoma rhodesiense cultivated at 28 degrees c with various tsetse fly tissues.metacyclic trypanosomes developed in populations of procyclic forms of four stocks of trypanosoma brucei rhodesiense cultivated at 28 degrees c in a liquid medium containing explants of tsetse fly head-salivary glands, alimentary tract, abdominal body wall, or thoracic muscle. the cultures became infective for mice 7-16 days after they were prepared, and infective trypanosomes were present for prolonged periods. in the culture series of stock trum 545, infectivity persisted for 138 days when the ...19863735153
interference between different serodemes of trypanosoma congolense in the establishment of superinfections in goats following transmission by tsetse.when domestic ruminants cyclically infected with trypanosoma congolense are superinfected with a different serodeme of the same species, an interference phenomenon occurs which delays the development of the second cyclical infection. experiments were carried out to investigate the influence of the time interval between the two infections on the degree of interference and to follow the course of the superinfection clinically, serologically and histologically. goats infected with tsetse-transmitte ...19863748602
apparent exhaustion of the variable antigen repertoires of trypanosoma vivax in infected cattle.three groups of cattle, each group comprising six animals, were inoculated intravenously with populations of bloodstream forms of trypanosoma vivax. the first group received t. vivax clone ildat 1.3 derived from an isolate from nigeria, while the other two received t. vivax stocks il 1875 or il 2133 isolated from coast province, kenya. one animal from the group that was infected with il 1875 died 8 weeks postinfection. the remaining 17 animals became aparasitemic in 8 to 12 weeks without interve ...19863770950
opposite effects of ecdysone and 20-hydroxyecdysone on in vitro uterus motility of a tsetse fly.in order to examine the possible effects of ecdysteroids on parturition, we studied in vitro the influence of ecdysone and 20-hydroxyecdysone on the motility of isolated uterus from virgin and pregnant female tsetse fly (glossina fuscipes). ecdysone initiates phasic uterine contractions or enhances the frequency of preexisting contractile activity. in contrast, uterine contractions are decreased or abolished by 20-hydroxyecdysone. pharmacological data indicate that tsetse fly uterus exhibits myo ...19863796208
expression of a polypeptide containing a dipeptide repeat is confined to the insect stage of trypanosoma brucei.the protozoan parasite trypanosoma brucei is transmitted between mammalian hosts by the tsetse fly (glossina spp.). trypanosomes ingested by the fly undergo a number of changes in the insect midgut during differentiation to procyclic forms. these include the loss of the variant specific glycoprotein (vsg) coat and the appearance of a common set of procyclic surface antigens. in order to investigate genes other than vsg genes which are expressed only at certain stages of the life cycle, the first ...19873808022
lesions and saliva-specific antibody responses in rabbits with immediate and delayed hypersensitivity reactions to the bites of glossina morsitans centralis.rabbits exposed to feeding tsetse flies developed cutaneous hypersensitivity responses to fly bites. these responses had characteristics of immediate and delayed type hypersensitivity. saliva components from the tsetse fly glossina morsitans centralis were electrophoretically separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. major salivary proteins of 160, 92, 66, 64, 55, 42, 33, 28, and 15 kilodaltons were identified. separated salivary components were transferred to nitro ...19863811131
susceptibility of buffaloes, cattle and goats to infection with different stocks of trypanosoma vivax transmitted by glossina morsitans centralis.a comparison was made of the susceptibility of buffaloes, cattle and goats to infection with trypanosoma vivax transmitted either by glossina morsitans centralis or by syringe inoculation. three different isolates of t vivax (two from east africa, one from west africa) were used to compare skin reactions, parasitaemia, anaemia and the development of trypanosome-specific antibodies in buffaloes, cattle and goats. african buffaloes reared in captivity in an area free from trypanosomiasis proved to ...19863827994
trypanosome hybrids generated in tsetse flies by nuclear fusion.genetic exchange may occur between two particular trypanosoma brucei clones simultaneously transmitted by the same tsetse fly. we report here that this exchange takes place in the fly, through nuclear fusion. the resulting hybrids appear to be sub-tetraploid, some particular dna sequences from one of the parental stocks being lost before enough cloned hybrid trypanosomes could be harvested for dna analysis. a further reduction of the dna content of these hybrids occurs gradually upon growth and ...19863830130
[efficacy against glossina morsitans submorsitans of screens of different colors, with or without addition of black mosquito netting]. 19853837926
high and low responsiveness of bovine lymphocytes to trypanosoma brucei in vitro: lack of correlation with resistance to trypanosomiasis.bovine peripheral blood lymphocytes (pbl) were stimulated to proliferate in vitro by live, irradiated or freeze-thawed trypanosoma brucei, but not by the isolated variant surface glycoprotein. the optimal dose was 10(5) trypanosomes per 5 x 10(5) lymphocytes in 0.2 ml. maximal proliferation was at day 5. of the 98 cattle tested, 36 were high-responders (stimulation indexes 20-104), 49 were low or non-responders (si 1-10) and 13 were intermediate. the responder status of individual animals did no ...19853871728
properties of a novel dna virus from the tsetse fly, glossina pallidipes.virus particles were isolated from hypertrophied salivary glands of the tsetse fly, glossina pallidipes collected near mombasa, kenya. purified virus particles were rod-shaped, 57 nm wide by 700 to 1300 nm long. particle lengths fell into two size classes, with 'short' particles averaging 869 nm and 'long' particles 1175 nm. the virus particles morphologically resembled elongated baculovirus nucleocapsids although, unlike baculoviruses, no fully enveloped virions were found in purified preparati ...19863950581
independent expression of the metacyclic and bloodstream variable antigen repertoires of trypanosoma brucei rhodesiense.the variable antigen repertoire expressed by metacyclic trypanosoma brucei rhodesiense is not influenced by the anamnestic expression whereby the variable antigen type (vat) ingested by a tsetse fly is present at high levels in early bloodstream populations of fly-infected mice. this has been demonstrated by feeding to glossina morsitans a trypanosome line expressing a vat which is normally a component of the metacyclic repertoire. the vat did not constitute a significantly increased proportion ...19863960594
mechanical transmission of rift valley fever virus by hematophagous diptera.experimental studies were conducted to determine if hematophagous diptera were capable of mechanical transmission of rift valley fever (rvf) virus to laboratory animals. all species tested (glossina morsitans, aedes aegypti, aedes taeniorhynchus, culex pipiens, stomoxys calcitrans, lutzomyia longipalpis, and culicoides variipennis) mechanically transmitted the virus to hamsters. mechanical transmission rates for g. morsitans ranged from 0-100%, with the probability of mechanical transmission pos ...19853970308
trypanosoma brucei rhodesiense: enhancement of infection rates in the tsetse fly, glossina morsitans, by feeding artificial bloodmeal mixtures.low mature salivary gland (sg) infection rates (6%) in less than 24-hour-old flies fed on blood containing bloodform trypanosomes can be significantly enhanced by feeding flies an artificial mixture containing procyclic forms in a red cell: culture medium mixture (procyclic mixture, sg rate = 21.0%). however, enhancement is not solely a function of the use of procyclic forms since blood forms fed to flies in the same red cell: culture medium mixture produce sg rates (15.4%) intermediate to those ...19853970311
neutralization of individual variable antigen types in metacyclic populations of trypanosoma brucei does not prevent their subsequent expression in mice.the trypanosoma brucei metacyclic population in the salivary glands of the tsetse fly displays a characteristic set of variable antigen types (vats) which represents only a restricted part of the parasite's total vat repertoire. after introduction into the mammalian host by fly bite, the metacyclics transform into bloodstream forms which retain expression of the metacyclic vats. specific antibodies, both polyvalent and monoclonal, have been used to neutralize separately 4 individual vats from me ...19853982856
probing by glossina morsitans centralis infected with pathogenic trypanosoma species. 19853992628
induction of systemic and local basophil and eosinophil responses in guinea pigs by the feeding of the tsetse fly glossina morsitans.guinea pigs infested with glossina morsitans weekly for 5 weeks exhibited marked peripheral blood basophil and eosinophil responses to each infestation, with a dominant cutaneous basophil response to challenge infestation. g. morsitans feeding was completed within 3--10 min, depending upon prior exposure, and flies were reluctant to feed and probed longer on hyperexposed animals. blood basophil responses exhibited the greatest increases over controls (up to 12-fold) compared to eosinophils (up t ...19854002604
laboratory testing of repellents against the tsetse glossina morsitans (diptera: glossinidae). 19854009624
characteristics of trypanosome variant antigen genes active in the tsetse fly.trypanosoma brucei contains a repertoire of more than 100 different genes for variant surface glycoproteins (vsgs). a small and strain-specific fraction of these genes is expressed in the salivary glands of the tsetse fly (m-genes), giving rise to metacyclic variable antigen types (m-vats). antibodies produced in a chronic trypanosome infection initiated by syringe inoculation of bloodstream forms into mammals (i.e. against b-vats), will react with most of the m-vats suggesting that these b-vats ...19854022771
extrachromosomal inheritance of susceptibility to trypanosome infection in tsetse flies. i. selection of susceptible and refractory lines of glossina morsitans morsitans.differences in susceptibility to infection with trypanosoma congolense between f1 families of glossina morsitans morsitans indicated that susceptibility is maternally inherited in this species of tsetse fly. twelve f1 families, six selected for susceptibility and six selected for refractoriness to infection, have been bred for up to 13 generations. the reciprocal differences demonstrated in the f1 generation persisted in these selected families over many generations, indicating that susceptibili ...19854026443
trypanosoma brucei: infectivity and immunogenicity of cultured parasites.trypanosoma brucei brucei, derived from the salivary glands of infected tsetse flies (glossina morsitans morsitans) and maintained in culture for over 4 years, were infective to both albino rats and tsetse flies. virulence was markedly enhanced during the first passage in albino rats or tsetse flies. irradiated cultured trypanosomes induced immunity to homologous challenge but not to tsetse fly or blood-induced challenge with the same stock.19854029345
differentiation in trypanosoma brucei: host-parasite cell junctions and their persistence during acquisition of the variable antigen coat.acquisition of the variable antigen-containing surface coat of trypanosoma brucei occurs at the metacyclic stage in the salivary glands of the tsetse fly vector. the differentiation of the metacyclic trypanosome in the gland has been studied by scanning electron microscopy and by transmission electron microscopy of thin sections and freeze-fracture replicas. the uncoated epimastigote trypanosomes (with a prenuclear kinetoplast) divide while attached to the salivary gland epithelium brush border ...19854030903
suppression of trypanosoma congolense, t. vivax and t. brucei infection rates in tsetse flies maintained on goats immunized with uncoated forms of trypanosomes grown in vitro.significant suppression in the incidence of cyclical development of trypanosoma congolense, t. vivax and t. brucei occurred in glossina morsitans centralis maintained on goats immunized with in vitro-propagated uncoated forms of t. congolense, t. vivax and t. brucei, respectively. this was observed when tsetse given a t. congolense-infected feed were subsequently maintained on uninfected immunized goats and also when uninfected tsetse were fed on immunized goats infected with t. congolense, t. v ...19854034247
methods to calculate survival rate in tsetse fly (glossina) populations. 19854037898
[socio-entomologic survey in human trypanosomiasis focus of yamba (peoples republic of congo)].a study carried out at villagers level in a focus infected by human trypanosomiasis (yamba, bouenza region, congo, mikengue ethnic group) revealed that modern medicin is recognized by them as the sole possibility to treat the sleeping sickness. the witch doctor, if he cannot transmit the sickness, is perfectly able to aggravate it. he is considered as the responsible for any fatal issue. tsetse flies are charged of transmitting the sickness as well as other biting insects (black flies, ceratopog ...19854068972
observations on age-grouping the tsetse fly, glossina pallidipes, by wing-fray and ovarian dissection, on the south kenya coast.female glossina pallidipes from biconical trap collections at five localities on the south kenya coast were age-grouped by wing-fray and ovarian condition, and their trypanosome infection rates determined. from simultaneous application of the two age-grouping methods to 991 female tsetse, 17 reproductive age-categories were recognized. separation into these categories was supported by a highly significant correlation between estimated age and proportion of tsetse uninfected by trypanosomes. limi ...19854073997
trypanotolerance in east african orma boran cattle.comparative studies on two types of large east african zebu (bos indicus) boran cattle, on a beef ranch in kenya, have indicated that a boran type bred by the orma tribe has a superior response to tsetse fly challenge. the orma boran when compared with an improved boran was found to have lower trypanosome infection rates and, when untreated, better control of anaemia and decreased mortality.19854090214
survival and reproductive performance of female glossina morsitans morsitans when maintained on livestock infected with salivarian trypanosomes. 19854096568
comparative analysis of the polytene chromosomes of glossina austeni and glossina morsitans morsitans. 19744140779
the occurrence of intracellular rickettsia-like organisms in the tsetse flies, glossina morsitans, g. fuscipes, g. brevipalpis and g. pallidipes. 19744151039
amino acid analyses of haemolymph of glossina morsitans morsitans (westwood). 19744151040
studies on the amino acids of the tsetse fly, glossina morsitans, maintained on in vitro and in vivo feeding systems. 19744153811
bacteroids in the ovaries of a tsetse fly. 19744208431
lipid content and composition of the tse-tse fly, glossina morsitans westwood. 19694310397
carbohydrate metabolism in flight muscle of the tsetse fly (glossina) and the blowfly (sarcophaga). 19694312541
oxaloacetic carboxylase in flight musculature of the tsetse fly. 19654379552
on the trypanosome-infection rate of glossina morsitans in the ulanga district (tanzania). 19684385524
oocyte differentiation and vitellogenesis in glossina morsitans westw. 19714400310
comparisons between three small collections of glossina morsitans morsitans (machado) (diptera: glossinidae) from the kilombero river valley, tanzania. 1. characteristics of flies exhibiting different patterns of behaviour. 19724404250
sterility from crosses between sub-species of the tsetse fly glossina morsitans. 19724404251
ultrastructural study of the midgut mycetome-bacteroids of the tsetse flies glossina morsitans, g. fuscipes, and g, brevipalpis (diptera, brachycera). 19724404253
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