| hybridization asymmetries in tsetse (diptera: glossinidae): role of maternally inherited factors and the tsetse genome. | among the morsitans-group of tsetse there are several pairs of taxa in which there is a marked hybridization asymmetry (ha), i.e., one cross produces significantly more offspring than does the reciprocal cross. to investigate the relative contribution of maternally inherited factors (mif) and chromosomal factors to ha, three hybrid lines were established in which flies have mif from one taxon and chromosome from another. ha was then compared among crosses of the parental taxa and crosses of each ... | 2000 | 11126547 |
| transport of methionine in trypanosoma brucei brucei. | african trypanosomes live free in the bloodstream and central nervous system of mammalian hosts and also within the midgut of the tsetse fly vectors which transmit them. the parasite plasma membrane represents the interface between both hosts and parasite, and trypanosomes accumulate many essential metabolites via specific transport processes. l-methionine uptake by procyclic and bloodstream forms of trypanosoma brucei has been measured and shown to be mediated by a transporter presenting simila ... | 2000 | 11163438 |
| the major cell surface glycoprotein procyclin is a receptor for induction of a novel form of cell death in african trypanosomes in vitro. | bloodstream forms (bsf) and procyclic culture forms (pcf) of african trypanosomes were incubated with a variety of lectins in vitro. cessation of cell division and profound morphological changes were seen in procyclic forms but not in bsf after incubation with concanavalin a (con a), wheat germ agglutinin and ricinus communis agglutinin. these lectins caused the trypanosomes to cease division, become round and increase dramatically in size, the latter being partially attributable to the formatio ... | 2000 | 11163441 |
| estimation of trypanosomal status by the buffy coat technique and an antibody elisa for assessment of the impact of trypanosomosis on health and productivity of n'dama cattle in the gambia. | the buffy coat/dark ground phase contrast technique (bct) and an indirect antibody enzyme immunoassay (elisa) were employed to assess the trypanosomal status of 32 n'dama cattle, aged 19-28 months, exposed to natural challenge of glossina morsitans submorsitans and g. palpalis gambiensis. prior to the start of the investigation animals experienced 9-16 months of tsetse challenge in the study area. blood and corresponding serum samples were examined monthly for a period of 8 months for patent par ... | 2001 | 11163695 |
| the surface coat of procyclic trypanosoma brucei: programmed expression and proteolytic cleavage of procyclin in the tsetse fly. | trypanosoma brucei, the protozoan parasite causing sleeping sickness, is transmitted by a tsetse fly vector. when the tsetse takes a blood meal from an infected human, it ingests bloodstream form trypanosomes that quickly differentiate into procyclic forms within the fly's midgut. during this process, the parasite loses the 10(7) molecules of variant surface glycoprotein that formed its surface coat, and it develops a new coat composed of several million procyclin molecules. procyclins, the prod ... | 2001 | 11171982 |
| mark-recapture and moran curve estimates of the survival probabilities of an island population of tsetse flies glossina morsitans morsitans (diptera: glossinidae). | a study on populations of glossina morsitans morsitans westwood on antelope island, lake kariba, zimbabwe provided jolly-seber (j-s) mark-recapture estimates of adult survival and moran curve estimates of the overall survival of all developmental stages. for females, moran survival estimates derived using ox fly-round catches showed similar trends to, but were more variable than, those calculated from j-s population estimates. regression of one set on the other removed only 26% of the variance. ... | 2001 | 11228585 |
| molecular characterization of two serine proteases expressed in gut tissue of the african trypanosome vector, glossina morsitans morsitans. | serine proteases are major insect gut enzymes involved in digestion of dietary proteins, and in addition they have been implicated in the process of pathogen establishment in several vector insects. the medically important vector, tsetse fly (diptera:glossinidiae), is involved in the transmission of african trypanosomes, which cause devastating diseases in animals and humans. both the male and female tsetse can transmit trypanosomes and both are strict bloodfeeders throughout all stages of their ... | 2001 | 11240636 |
| characterization of genes expressed in the salivary glands of the tsetse fly, glossina morsitans morsitans. | salivary gland products of haematophogous insects including tsetse flies (diptera: glossinidia) are involved in antihaemostasis to allow for efficient blood feeding. in addition, salivary products of tsetse are thought to indirectly support the metacyclogenesis and eventual transmission of the african trypanosome protozoan parasites to their mammalian hosts. we have previously characterized the major anticoagulant, tsetse thrombin inhibitor (tti), from salivary extracts, and described molecular ... | 2001 | 11240638 |
| the effect of temperature and saturation deficit on mortality in populations of male glossina m. morsitans (diptera: glossinidae) in zimbabwe and tanzania. | the methods of bailey and of jolly and seber were used to provide maximum likelihood estimates of population parameters for jackson's classical mark-recapture experiments on males of the tsetse fly glossina m. morsitans westwood. these were compared with jolly-seber (j-s) estimates for the same fly from more recent work on antelope island, lake kariba, zimbabwe. the bailey estimates of birth and death rates and total population size had markedly lower variances than jackson's originals. both set ... | 2001 | 11260721 |
| use of deltamethrin 'pour-on' insecticide for the control of cattle trypanosomosis in the presence of high tsetse invasion. | a deltamethrin 'pour-on' insecticide was applied monthly to over 2000 cattle exposed to a high challenge of drug-resistant trypanosomes and high tsetse re-invasion pressure in the ghibe valley, south-west ethiopia. blood samples were taken monthly from an average of 760 cattle for determination of pcv and presence of trypanosomes. the area of the valley is approximately 350 km2 and the cattle grazed in roughly four locations covering about a quarter to half of the area. two years before the tria ... | 2001 | 11297107 |
| the endosymbionts of tsetse flies: manipulating host-parasite interactions. | through understanding the mechanisms by which tsetse endosymbionts potentiate trypanosome susceptibility in tsetse, it may be possible to engineer modified endosymbionts which, when introduced into tsetse, render these insects incapable of transmitting parasites. in this study we have assayed the effect of three different antibiotics on the endosymbiotic microflora of tsetse (glossina morsitans morsitans). we showed that the broad-spectrum antibiotics, ampicillin and tetracycline, have a dramati ... | 2001 | 11334953 |
| a novel application of gene arrays: escherichia coli array provides insight into the biology of the obligate endosymbiont of tsetse flies. | symbiotic associations with microorganisms are pivotal in many insects. yet, the functional roles of obligate symbionts have been difficult to study because it has not been possible to cultivate these organisms in vitro. the medically important tsetse fly (diptera: glossinidae) relies on its obligate endosymbiont, wigglesworthia glossinidia, a member of the enterobacteriaceae, closely related to escherichia coli, for fertility and possibly nutrition. we show here that the intracellular wiggleswo ... | 2001 | 11404467 |
| the changing distribution of two riverine tsetse flies over 15 years in an increasingly cultivated area of burkina faso. | changes in the distribution of two riverine tsetse flies, glossina tachinoides westwood and glossina palpalis gambiensis vanderplank are described in an agro-pastoral area of burkina faso subject to increasing human population pressure and land use change. two similar entomological surveys (one trap every 100 m, 120 km of river) were conducted in 1981 and 1996. changes in tsetse distribution were compared to land use changes through high resolution remote sensing imagery (landsat, spot). there w ... | 2001 | 11415469 |
| a density-dependent model with reinvasion for estimating tsetse fly populations (diptera: glossinidae) through trapping. | a simple density-dependent reinvasion model is described and used to estimate tsetse fly populations on the basis of removal trapping experiments. the model was tested on glossina fuscipes fuscipes newstead in the central african republic and g. palpalis palpalis (robineau-desvoidy) in the republic of congo (brazzaville). the density-dependence is modelled by postulating that the inflow of flies each day is proportional to the deficit relative to the equilibrium population. non-linear least squa ... | 2001 | 11415471 |
| spatial and temporal distribution of tsetse fly trap catches at nguruman, southwest kenya. | spatial and temporal dynamics of rapidly growing populations of tsetse flies at nguruman, southwest kenya during 1993-1995, were investigated, following six years of intensive population suppression with traps over a c. 100 km2 area. the two tsetse species present were randomly distributed in the short rainy season, but were aggregated in the dry and long rainy seasons. maximum temperature was the dominant weather factor associated with the degree of aggregation. trends in catches at 20 fixed si ... | 2001 | 11415476 |
| procyclins, proteases and proteomics: dissecting trypanosomes in the tsetse fly. | the forms of african trypanosomes that live in tsetse fly vectors are coated with lipid-anchored proteins and glycoproteins known collectively as procyclins. procyclins are expressed during development in the fly in a multiplicity of isoforms yet their functions remain unknown. recent studies involving a multidisciplinary synthesis of tsetse biology, immunochemistry, biological chemistry and mass spectrometry have yielded much new information about procyclins, which could now provide an unparall ... | 2001 | 11435080 |
| 1-octen-3-ol isolated from bont ticks attracts amblyomma variegatum. | volatiles from various life-stages of the bont ticks amblyomma variegatum and a. hebraeum were collected by using solid-phase microfibers and charcoal traps. an octenol isomer was found to be a major constituent of most of the tick material sampled and was identified as 1-octen-3-ol by gas chromatography-mass spectrometry and by using antenna of the tsetse fly glossina brevipalpis in gas chromatography-linked antennogram detection. release of this compound increased during molt to adulthood and ... | 2001 | 11441439 |
| genome size determination and coding capacity of sodalis glossinidius, an enteric symbiont of tsetse flies, as revealed by hybridization to escherichia coli gene arrays. | recent molecular characterization of various microbial genomes has revealed differences in genome size and coding capacity between obligate symbionts and intracellular pathogens versus free-living organisms. multiple symbiotic microorganisms have evolved with tsetse fly, the vector of african trypanosomes, over long evolutionary times. although these symbionts are indispensable for tsetse fecundity, the biochemical and molecular basis of their functional significance is unknown. here, we report ... | 2001 | 11443086 |
| unravelling the phylogenetic relationships of african trypanosomes of suids. | african trypanosomes of the subgenera nannomonas and pycnomonas have been recorded from both wild and domestic suids. however, complete descriptions of some of these trypanosomes with regard to host range, pathogenicity, transmission and distribution are still lacking. neither the recently described trypanosoma (nannomonas) godfreyi nor trypanosoma (nannomonas) congolense tsavo have been isolated from mammalian hosts, while trypanosoma (pycnomonas) suis remains the rarest of the salivarian trypa ... | 2001 | 11444615 |
| deletion of a novel protein kinase with px and fyve-related domains increases the rate of differentiation of trypanosoma brucei. | growth control of african trypanosomes in the mammalian host is coupled to differentiation of a non-dividing life cycle stage, the stumpy bloodstream form. we show that a protein kinase with novel domain architecture is important for growth regulation. zinc finger kinase (zfk) has a kinase domain related to rac and s6 kinases flanked by a fyve-related zinc finger and a phox (px) homology domain. to investigate the function of the kinase during cyclical development, a stable transformation proced ... | 2001 | 11454198 |
| antigenic variation in trypanosomes: enhanced phenotypic variation in a eukaryotic parasite. | african trypanosomes are unicellular, eukaryotic parasites that live extracellularly in a wide range of mammals, including humans. they have a surface coat, composed of variant surface glycoprotein (vsg), which probably is essential and acts as a defence against general innate immunity and against acquired immunity directed at invariant surface antigens. in effect, the vsg is the only antigen that the host can target, and each trypanosome expresses only one vsg. to counter specific antibodies ag ... | 2001 | 11461029 |
| effect of gamma-irradiation on serum samples on the diagnostic performance of elisa methods for the detection of trypanosomal antibodies. | the study investigated the effect of gamma-irradiation on bovine serum samples on the ability of enzyme-linked immunosorbent assay (elisa) methods to detect trypanosomal antibodies. the serum samples were analysed using two standardised indirect elisa systems. higher measurement values were observed for most gamma-irradiated antibody positive and negative test samples. using cut-off points, determined from the analysis of a non-irradiated trypanosomal antibody-negative population, the gamma-irra ... | 2001 | 11470177 |
| genetic differentiation of glossina morsitans centralis populations. | variation at mitochondrial and microsatellite loci was used to study the breeding and dispersal structure of glossina morsitans centralis, in six natural populations from botswana, the caprivi strip (namibia), zambia, and in a laboratory culture derived from singida, tanzania. only seven mitochondrial haplotypes were found. mean diversity averaged over the six natural populations was 0.216 +/- 0.085. the fixation index fst = 0.866 indicated a high degree of genetic differentiation among populati ... | 2001 | 11520361 |
| the origins of a new trypanosoma brucei rhodesiense sleeping sickness outbreak in eastern uganda. | sleeping sickness, caused by two trypanosome subspecies, trypanosoma brucei gambiense and trypanosoma brucei rhodesiense, is a parasitic disease transmitted by the tsetse fly in sub-saharan africa. we report on a recent outbreak of t b rhodesiense sleeping sickness outside the established south-east ugandan focus, in soroti district where the disease had previously been absent. soroti district has been the subject of large-scale livestock restocking activities and, because domestic cattle are im ... | 2001 | 11530149 |
| multiple procyclin isoforms are expressed differentially during the development of insect forms of trypanosoma brucei. | transmission of trypanosoma brucei by the tsetse fly entails several rounds of differentiation as the parasite migrates through the digestive tract to the salivary glands of its vector. differentiation of the bloodstream to the procyclic form in the fly midgut is accompanied by the synthesis of a new coat consisting of ep and gpeet procyclins. there are three closely related ep isoforms, two of which (ep1 and ep3) contain n-glycans. to identify the individual ep isoforms that are expressed early ... | 2001 | 11575917 |
| a contribution towards simplifying area-wide tsetse surveys using medium resolution meteorological satellite data. | a raster or grid-based geographic information system with data on tsetse, trypanosomiasis, animal production, agriculture and land use has recently been developed in togo. the area-wide sampling of tsetse fly, aided by satellite imagery, is the subject of two separate papers. this paper follows on a first paper, published in this journal, describing the generation of digital tsetse distribution and abundance maps and how these accord with the local climatic and agro-ecological setting. such maps ... | 2001 | 11583596 |
| a trypanosome structure involved in transmitting cytoplasmic information during cell division. | african trypanosomes are protozoan parasites that cause sleeping sickness in humans through a tsetse fly vector. the procyclic form of trypanosoma brucei has a single, attached flagellum that describes a helical path along the cell from posterior to anterior. during division, a specific flagellum-flagellum connection is elaborated between the new and old flagellum. this connector was present only during cell duplication and was found to be involved in the replication of the helical cell pattern ... | 2001 | 11641501 |
| degradation of the unstable ep1 mrna in trypanosoma brucei involves initial destruction of the 3'-untranslated region. | kinetoplastid protozoa regulate their gene expression primarily through control of mrna degradation and translation. we describe here the degradation of three reporter mrnas in trypanosoma brucei. one mrna had the 3'-untranslated region (3'-utr) from the developmentally regulated ep1 mrna, which is abundant in the procyclic (tsetse fly) form of the parasite but is almost undetectable in the bloodstream form. this untranslated region includes a 26 nt u-rich sequence that causes extreme rna instab ... | 2001 | 11713321 |
| characterization of the adenosine deaminase-related growth factor (adgf) gene family in drosophila. | a novel family of growth factors, with sequence similarity to adenosine deaminase, has been identified in various organisms including flesh fly, tsetse fly, sand fly, mollusk and human. the human homologue, cecr1, is a candidate gene for the genetic disorder cat eye syndrome. here, we describe six members of this growth factor family in drosophila and two in vertebrates. the six drosophila genes, named adenosine deaminase-related growth factors (adgf), are found at three different chromosomal lo ... | 2001 | 11738815 |
| glycosylphosphatidylinositol-anchored surface molecules of trypanosoma congolense insect forms are developmentally regulated in the tsetse fly. | procyclic culture forms of trypanosoma congolense have been shown to express a glutamic acid/alanine-rich protein (garp) on their surface. by labelling t. congolense procyclic culture forms with glycosylphosphatidylinositol (gpi) precursors, we show that garp is bound to the membrane by a gpi anchor and demonstrate the presence of two additional gpi-anchored surface molecules of 24-34 and 58 kda that are abundantly expressed. the 24-34 kda molecule, which is recognised by monoclonal antibodies t ... | 2002 | 11755181 |
| [the epidemiology of human african trypanosomiasis: a complex multifactorial history]. | sleeping sickness has long been known from descriptions by arab merchants and slave traders. however it was not until 1901 that forbes discovered the offending agent and 1903 that bruce described the role of the tsetse fly. the basic epidemiological transmission cycle was described less than 10 years later. although the main outline of the original model can still be considered as sound, subsequent research has greatly expanded our knowledge. molecular biology has identified different parasites ... | 2001 | 11803821 |
| principles of area-wide integrated tsetse fly control using the sterile insect technique. | the tsetse fly and the disease trypanosomosis it transmits, is one of the most severe medical and veterinary problems in africa, infecting around 50,000 people every year and preventing the development of sustainable and productive agricultural systems. the most efficient way to contain the disease is by the management of entire populations of the vector (area-wide approach) using a combination of several control methods in an integrated pest management campaign. a very powerful method for integ ... | 2001 | 11803833 |
| population structure of the tsetse fly glossina pallidipes estimated by allozyme, microsatellite and mitochondrial gene diversities. | diversities at nuclear and mitochondrial loci were examined in eleven natural populations of glossina pallidipes from east and southern africa. alleles in each class of loci are assumed to be selectively neutral. allozyme gene diversities (heterozygosities) averaged over eight loci were 0.146 among seven kenya populations and 0.201 among four southern african populations. microsatellite diversity averaged over three loci was 0.250 in kenya and only 0.218 in southern africa. mitochondrial diversi ... | 2002 | 11841501 |
| molecular characterization of three gut genes from glossina morsitans morsitans: cathepsin b, zinc-metalloprotease and zinc-carboxypeptidase. | insect gut enzymes are involved in digestion of dietary proteins. additionally, these enzymes have been implicated in the process of pathogen establishment in several insects including the tsetse fly (diptera:glossinidae), which is the vector for african trypanosomes. both the male and female tsetse can transmit trypanosomes and are strict blood feeders during all stages of their development. here, we describe the molecular characterization of three gut genes: cathepsin b (gmcatb), zinc-metallop ... | 2002 | 11841503 |
| [african trypanosomiasis--a rare imported disease]. | this year at least nine cases of african trypanosomiasis have occurred among europeans visiting the serengeti park in tanzania. one of them was a 26-year-old norwegian woman who was bitten by a tsetse fly in her face. she developed fever, nausea and other symptoms, and had thrombocytopenia and pathological liver values; trypanosoma parasites were demonstrated in her blood. the recommended drug, suramin, was not readily available in tanzania and she was transported to oslo. the diagnosis was conf ... | 2002 | 11851292 |
| [trypanosomiasis--a real risk for tourists visiting national parks in tanzania]. | african sleeping sickness is no longer a rare disease among tourists visiting national parks in tanzania. the disease is caused by a parasite, trypanosoma brucei, which is transmitted by the tsetse fly. two species infect humans: trypanosoma brucci gambiense and trypanosoma brucei rhodesiense; the last form is re-emerging in parts of africa. untreated this disease carries a mortality of nearly 100%. this article describes a case of african sleeping sickness in a tourist visiting tanzania, which ... | 2002 | 11851293 |
| the cell biology of parasitism in trypanosoma brucei: insights and drug targets from genomic approaches? | the african trypanosome, trypanosoma brucei exhibits a complex, digenetic life cycle that alternates between the tsetse fly vector and the mammalian host. the life cycle is characterised by a complex series of cell type differentiations and variations in metabolism. in addition the trypanosome exhibits a particular cell biology that has become adapted for its role as a parasite. this article places some of these areas in a frame-work that considers the role of cellular processes in parasitism. i ... | 2002 | 11860364 |
| chemotherapy of human african trypanosomiasis. | human african trypanosomiasis or sleeping sickness is resurgent [1,2]. the disease is caused by subspecies of the parasitic haemoflagellate, trypanosoma brucei. infection starts with the bite of an infected tsetse fly (glossina spp.). parasites move from the site of infection to the draining lymphatic vessels and blood stream. the parasites proliferate within the bloodstream and later invade other tissues including the central nervous system. once they have established themselves within the cns, ... | 2002 | 11860365 |
| pan african group takes lead against the tsetse fly. | | 2002 | 11879881 |
| immunopeptides in the defense reactions of glossina morsitans to bacterial and trypanosoma brucei brucei infections. | several dipteran insects are vectors of parasites causing major human infectious diseases. among these, the tsetse fly, glossina spp., is responsible for the transmission of trypanosomes, the pathogens responsible for sleeping sickness in africa. a better understanding of insect-parasite interactions will help establish new strategies to fight this important often fatal disease. antimicrobial peptides (amps) are part of the humoral immune response in insects during bacterial, fungal and parasiti ... | 2002 | 11886771 |
| ku is important for telomere maintenance, but not for differential expression of telomeric vsg genes, in african trypanosomes. | trypanosome antigenic variation, involving differential expression of variant surface glycoprotein (vsg) genes, has a strong association with telomeres and with dna recombination. all expressed vsgs are telomeric, and differential activation involves recombination into the telomeric environment or silencing/activation of subtelomeric promoters. a number of pathogen contingency gene systems associated with immune evasion involve telomeric loci, which has prompted speculation that chromosome ends ... | 2002 | 11919193 |
| sustainability of tsetse control by subsequent treatment of 10% of a previously treated ugandan cattle population with 1% w/v deltamethrin. | this study was conducted in masaba and masafu sub-counties, busia district, uganda to assess the effect on the tsetse fly population of first treating all cattle with 1% w/v deltamethrin pour-on for a few months, followed by treating 10% of the cattle population. treatment of all cattle for 6 months resulted in a significant reduction in the density of tsetse flies from 6.3 to 0.1 flies/trap/day (ftd), a 98.4% reduction. during the same period, the point prevalence of bovine trypanosomosis dropp ... | 2002 | 11969108 |
| serum xanthine oxidase: origin, regulation, and contribution to control of trypanosome parasitemia. | african trypanosomiasis is caused by salivarian trypanosomes, tsetse fly-transmitted protozoa that inhabit the blood plasma, lymph and interstitial fluids, and, in the case of trypanosoma brucei species, also the cerebrospinal fluid of mammal hosts. trypanosomiasis in people and domestic animals manifests as recurring waves of parasites in the blood and is typically fatal. in contrast, trypanosomiasis in cape buffaloes, which are naturally selected to resist the disease, is characterized by the ... | 2002 | 11970851 |
| area-wide biological control of disease vectors and agents affecting wildlife. | two examples of area-wide programmes, employing the sterile insect technique (sit), which have eradicated a parasite and a disease vector common to domestic and wild animals are described. new world screwworm (nws), cochliomyia hominivorax, caused significant morbidity and mortality of livestock and wild mammals in tropical and subtropical areas of america before eradication was achieved in north america using the sit and other components of an integrated pest management (ipm) programme. movemen ... | 2002 | 11974628 |
| galactose metabolism is essential for the african sleeping sickness parasite trypanosoma brucei. | the tsetse fly-transmitted protozoan parasite trypanosoma brucei is the causative agent of human african sleeping sickness and the cattle disease nagana. the bloodstream form of the parasite uses a dense cell-surface coat of variant surface glycoprotein to escape the innate and adaptive immune responses of the mammalian host and a highly glycosylated transferrin receptor to take up host transferrin, an essential growth factor. these glycoproteins, as well as other flagellar pocket, endosomal, an ... | 2002 | 11983889 |
| syntheses of racemic and diastereomeric mixtures of 3,7,11,15-tetramethylhentriacontane and 4,8,12,16-tetramethyldotriacontane, the cuticular tetramethylalkanes of the tsetse fly, glossina brevipalpis. | cuticular hydrocarbons of the tsetse fly, glossina brevipalpis, contain 3,7,11,15-tetramethylhentriacontane and 4,8,12,16-tetramethyldotriacontane as possible candidates for its contact sex pheromone. these were synthesized as racemic and diastereomeric mixtures starting from racemic citronellol and employing phenyl-sulfone-mediated chain-elongation as the key reaction. | 2002 | 12005053 |
| odor composition of preferred (buffalo and ox) and nonpreferred (waterbuck) hosts of some savanna tsetse flies. | a previous study on the feeding responses of tsetse flies, glossina morsitans morsitans, implicated the existence of allomonal barriers, both volatile and nonvolatile, on the nonpreferred host, waterbuck, kobus defassa. in the present study, electroantennogram-active compounds in odors from waterbuck were compared with those of two preferred hosts of tsetse flies, buffalo, syncerus caffer, and ox, bos indicus. odors from the three bovids were trapped on activated charcoal and/or reverse-phase (o ... | 2002 | 12049234 |
| campaign launched to eliminate tsetse fly, which has turned much of africa into a green desert. | | 2002 | 12083713 |
| seasonal variations in the distribution and abundance of the tsetse fly, glossina morsitans morsitans in eastern zambia. | the seasonal changes in the distribution of glossina morsitans morsitans westwood (diptera: glossinidae) and its main host, cattle, were examined in a cultivated area of the plateau of eastern zambia. during four consecutive years, the tsetse and cattle populations were monitored along a fly-round transect traversing the two main vegetation types in the study area. these were miombo, a one-storied open woodland with the genera brachystegia and julbernardia dominant, and munga, a one- or two-stor ... | 2002 | 12109711 |
| health and ecological dilemmas. sleeping sickness. | although trypanosomiasis is one of the major parasitic diseases facing african people, blind efforts to control the disease may cause greater human suffering by damaging the environment. trypanosomiasis, commonly known as sleeping sickness, is spread by the bite of the tsetse fly and affects both humans and cattle. the disease usually causes wasting and emaciation; the human or animal wants to sleep all the time, and death may occur within a few months or years. the tsetse fly inhabits an are ... | 1992 | 12159268 |
| cloning and functional expression of a fat body-specific chitinase cdna from the tsetse fly, glossina morsitans morsitans. | a chitinase cdna, gchit1 was isolated from glossina morsitans morsitans and shown to be specifically expressed in fat body tissue. gchit1 is encoded by a 1.6 kb mrna with a putative open reading frame (orf) of 460 amino acids (predicted pi=7.5, m.w.=51kda) that contains a signal peptide domain and two potential n-linked glycosylation sites. the orf exhibits homology to various chitinases characterized from insects. it has the conserved catalytic site residues and the cysteine-rich 3'-end domain ... | 2002 | 12213234 |
| identification of major soluble salivary gland proteins in teneral glossina morsitans morsitans. | salivary glands of tsetse flies (diptera: glossinidiae) contain molecules that are involved in preventing blood clotting during feeding as well as molecules thought to be intimately associated with trypanosome development and maturation. here we present a protein microchemical analysis of the major soluble proteins of the salivary glands of glossina morsitans morsitans, an important vector of african trypanosomes. differential solubilization of salivary proteins was followed by reverse-phase, hi ... | 2002 | 12213241 |
| parasitological prevalence of bovine trypanosomosis in kindo koisha district, wollaita zone, south ethiopia. | a cross sectional survey to determine the distribution and prevalence of trypanosomosis was conducted in kindo koisha district, in the wollaita zone in southern ethiopia. a total of 1 008 adult cattle was examined at eight different localities. dark field examination of the buffy coat, as well as stained thin blood film examination and packed cell volume (pcv) evaluation were the diagnostic techniques used. the overall prevalence of bovine trypanosomosis was 15 %. among the positive animals, 108 ... | 2002 | 12233995 |
| microsatellite diversities and gene flow in the tsetse fly, glossina morsitans s.l. | tsetse flies occupy discontinuous habitats and gene flow among them needs to be investigated in anticipation of area-wide control programs. genetic diversities were estimated at six microsatellite loci in seven glossina morsitans submorsitans newstead (diptera: glossinidae) populations and five microsatellite loci in six g. m. morsitans westwood populations. nei's unbiased diversities were 0.808 and 76 alleles in g. m. submorsitans and 0.727 and 55 alleles in g. m. morsitans. diversities were le ... | 2002 | 12243230 |
| the sahel: drought, desertification and famine. | between the end of sahel's 1968-73 drought and the early 1980s, the production of the drought-resistant sorghum and millet was increasing at about 1% a year, but simultaneously the population was growing by about 2.5% a year. a 1982 un study of the developing world's carrying capacity found that given the current low levels of agricultural technology used, about half the sahelian countries could not be expected to feed themselves. the sahel's demographic picture is complicated by the way diffe ... | 1985 | 12313941 |
| the scourge of human african trypanosomiasis. | human african trypanosomiasis (sleeping sickness) is a parasitic disease caused by two different trypanosome subspecies, trypanosoma brucei rhodesiense and t.b. gambiense. each causes a different form of the disease. untreated, the outcome of both infections is death. sleeping sickness occurs exclusively on the african continent, south of the sahara. it is restricted to the distribution area of its vector, glassina or tsetse fly. 36 out of the 52 african countries are considered endemic for slee ... | 1995 | 12319651 |
| trypanosomiasis re-emerges under cover of war. | the incidence of trypanosomiasis has increased in southern sudan along the border of the central african republic; up to 30% of the population is infected in some areas. a study conducted by care and the us centers for disease control (cdc) has shown that the disease has spread to over 30,000 people in tambura county alone; up to 4% of the local population is expected to die this year. according to the local coordinator for care, the pyramidal effect is great; when a tsetse fly bites a human, ... | 1997 | 12321240 |
| partial structure of glutamic acid and alanine-rich protein, a major surface glycoprotein of the insect stages of trypanosoma congolense. | the tsetse fly transmitted salivarian trypanosome, trypanosoma congolense of the subgenus nanomonas, is the most significant of the trypanosomes with respect to the pathology of livestock in sub-saharan africa. unlike the related trypanosome trypanosoma brucei of the subgenus trypanozoon, the major surface molecules of the insect stages of t. congolense are poorly characterized. here, we describe the purification and structural characterization of the glutamic acid and alanine-rich protein, one ... | 2002 | 12368279 |
| [tsetse fly wings, an identity card of the insect?]. | the size of tsetse flies is often associated with population dynamics and vectorial capacity parameters. adult fly size is generally estimated from measurements of wing segments. to take measure of the wing, a semi-automatic software was developed by cirad-emvt and ird. it was used in wild populations of glossina tachinoides westwood and g. palpalis gambiensis vanderplank (diptera: glossinidae) trapped near bobo-dioulasso, burkina faso. from an numeric picture of the wing, the software calculate ... | 2002 | 12375372 |
| photographic polytene chromosome maps for glossina morsitans submorsitans (diptera: glossinidae): cytogenetic analysis of a colony with sex-ratio distortion. | photographic polytene chromosome maps from trichogen cells of pharate adult glossina morsitans submorsitans were constructed. using the standard system employed to map polytene chromosomes of drosophila, the characteristic landmarks were described for the x chromosome and the two autosomes (l1 and l2). sex-ratio distortion, which is expressed in male g. m. submorsitans, was found to be associated with an x chromosome (x8) that contains three inversions in each arm. preliminary data indicate no d ... | 2002 | 12416619 |
| proventriculus-specific cdnas characterized from the tsetse, glossina morsitans morsitans. | peritrophic matrix (peritrophic membrane or pm) is an important structure in the gut of most insects at some stage in their development. it is composed of chitin, proteins and proteoglycans. multiple roles for the pm ranging from partitioning of digestive enzymes and food to protection of gut epithelial cells from viral and parasitic invasion have been proposed. while most adult members of diptera have a type i pm synthesized in response to a blood meal, the medically and agriculturally importan ... | 2002 | 12429118 |
| stage-specific requirement of a mitogen-activated protein kinase by trypanosoma brucei. | in cycling between the mammalian host and the tsetse fly vector, african trypanosomes undergo adaptive differentiation steps that are coupled to growth control. the signaling pathways underlying these cellular processes are largely unknown. mitogen-activated protein kinases (mapks) are known mediators of growth and differentiation in other eukaryotic organisms. to establish the function of a mapk homologue, tbmapk2, in t. brucei, a null mutant was constructed. bloodstream forms of a deltamapk2/d ... | 2002 | 12429824 |
| ex vivo and in vitro identification of a consensus promoter for vsg genes expressed by metacyclic-stage trypanosomes in the tsetse fly. | the trypanosome variant surface glycoprotein (vsg) is first expressed during differentiation to the infective, metacyclic population in tsetse fly salivary glands. unlike the vsg genes expressed by bloodstream form trypanosomes, metacyclic vsgs (mvsgs) have their own promoters. the scarcity of metacyclic cells has meant that only indirect approaches have been used to study these promoters, and not even their identities have been agreed on. here, we isolated trypanosomes by dissection from saliva ... | 2002 | 12477800 |
| fold-recognition analysis predicts that the tag protein family shares a common domain with the helix-hairpin-helix dna glycosylases. | the escherichia coli protein tag is traditionally regarded as an archetype of one of four classes of n-alkylpurine dna glycosylases. however, its structure and phylogenetic relationship to other glycosylases remains a mystery. fold-recognition and sequence profile analyses suggest that tag shares the catalytic domain with helix-hairpin-helix (hhh) glycosylases such as muty, alka and endoiii, but its n- and c-termini together form a unique his2cys2 cluster. the findings presented in this paper pr ... | 2002 | 12509243 |
| the major protein in the midgut of teneral glossina morsitans morsitans is a molecular chaperone from the endosymbiotic bacterium wigglesworthia glossinidia. | molecules in the midgut of the tsetse fly (diptera: glossinidiae) are thought to play an important role in the life cycle of african trypanosomes by influencing their initial establishment in the midgut and subsequent differentiation events that ultimately affect parasite transmission. it is thus important to determine the molecular composition of the tsetse midgut to aid in understanding disease transmission by these medically important insect vectors. here, we report that the most abundant pro ... | 2002 | 12530210 |
| growth and mortality in sheep and goats under high tsetse challenge in kenya. | trypanosomosis is a major impediment to livestock production and economic development in those areas of africa where it is endemic. although small ruminants appear to perform better than cattle in various agro-ecological zones, the importance of trypanosomosis has not been extensively investigated in these livestock. this study was designed to investigate the prevalence of trypanosomosis in sheep and goats in an endemic area and to evaluate the performance of different breeds under high tsetse c ... | 2002 | 12537387 |
| phosphorylation of gpeet procyclin is not necessary for survival of trypanosoma brucei procyclic forms in culture and in the tsetse fly midgut. | | 2003 | 12615329 |
| essential roles for gpi-anchored proteins in african trypanosomes revealed using mutants deficient in gpi8. | the survival of trypanosoma brucei, the causative agent of sleeping sickness and nagana, is facilitated by the expression of a dense surface coat of glycosylphosphatidylinositol (gpi)-anchored proteins in both its mammalian and tsetse fly hosts. we have characterized t. brucei gpi8, the gene encoding the catalytic subunit of the gpi:protein transamidase complex that adds preformed gpi anchors onto nascent polypeptides. deletion of gpi8 (to give deltagpi8) resulted in the absence of gpi-anchored ... | 2003 | 12631733 |
| antigenic variation and the african trypanosome genome. | african trypanosomes are protozoan parasites that reside in the mammalian bloodstream where they constantly confront the immune responses directed against them. they keep one-step-ahead of the immune system by continually switching from the expression of one variant surface glycoprotein (vsg) on their surface to the expression of another immunologically distinct vsg-a phenomenon called antigenic variation. about 1000 vsg genes (vsgs) and pseudo-vsgs are scattered throughout the trypanosome genom ... | 2003 | 12659976 |
| tsetse fly population genetics: an indirect approach to dispersal. | tsetse populations are distributed discontinuously, particularly the morsitans group. dispersal among diverse populations cannot easily be measured directly because the geographical distances between them can be too great to have a reasonable expectation of recapturing experimentally released flies. moreover, reproductive success of widely dispersed flies might be poor. the question of dispersal rates in tsetse is immediately important because area-wide eradication plans involving the sterile in ... | 2003 | 12689645 |
| surface coat remodeling during differentiation of trypanosoma brucei. | african trypanosomes (trypanosoma brucei) are digenetic parasites whose lifecycle alternates between the mammalian bloodstream and the midgut of the tsetse fly vector. in mammals, proliferating long slender parasites transform into non-diving short stumpy forms, which differentiate into procyclic forms when ingested by the tsetse fly. a hallmark of differentiation is the replacement of the bloodstream stage surface coat composed of variant surface glycoprotein (vsg) with a new coat composed of p ... | 2003 | 12716904 |
| the development of trypanosoma brucei within the tsetse fly midgut observed using green fluorescent trypanosomes. | background: the protozoan pathogen, trypanosoma brucei, undergoes complex cycles of differentiation and multiplication in its vector, the tsetse fly, genus glossina. flies are refractory to infection and resistance mechanisms operate at a number of levels and timepoints. here we have used highly conspicuous green fluorescent trypanosomes to study the early events in establishment of infection in the fly midgut. results: less than 10% of the bloodstream form trypanosomes in the infected feed diff ... | 2003 | 12769824 |
| a hormone from the uterus of the tsetse fly, glossina morsitans, stimulates parturition and abortion. | unlike most insects, the tsetse female gives birth to a single, fully grown larva at the culmination of each pregnancy cycle. the expulsion of the larva is regulated by a hormone present in rich abundance within the female's uterus. the hormone elicits parturition when injected into neck-ligated females at late stages of pregnancy and abortion when injected at earlier stages. we refer to this highly active material (0.043 uterus equivalents stimulates parturition in 50% of the females) as partur ... | 1997 | 12769917 |
| parturition hormone in the tsetse glossina morsitans: activity in reproductive tissues from other species and response of tsetse to identified neuropeptides and other neuroactive compounds. | parturition hormone (ph) activity is present not only in the uterus of the tsetse glossina morsitans but also in the oviducts of bombyx mori and schistocerca gregaria, as well as the ejaculatory duct of s. gregaria males. activity thus appears to be present in the reproductive ducts of diverse insect taxa. to determine whether any of the common insect neuropeptides are capable of mimicking the effect of ph, 35 identified neuropeptides and analogs were evaluated for ph activity. modest ph activit ... | 2000 | 12770225 |
| the human serum resistance associated gene is ubiquitous and conserved in trypanosoma brucei rhodesiense throughout east africa. | the human serum resistance associated (sra) gene isolated from a ugandan strain of trypanosoma brucei rhodesiense has been shown to be capable by itself of conferring the trait of human infectivity on t.b. brucei by transfection. this gene has also been identified in several other isolates of t.b. rhodesiense, but not in the other human pathogenic trypanosome in africa, t.b. gambiense, casting doubt on its ubiquity and function. here, we show that this gene occurs in t.b. rhodesiense from sleepi ... | 2002 | 12798017 |
| depletion of gim5 causes cellular fragility, a decreased glycosome number, and reduced levels of ether-linked phospholipids in trypanosomes. | microbody division in mammalian cells, trypanosomes, and yeast depends on the pex11 microbody membrane proteins. the function of pex11 is not understood, and the suggestion that it affects microbody (peroxisome) numbers in mammals and yeast, because it plays a role in beta-oxidation of fatty acids, is controversial. pex11 and two pex11-related proteins, gim5a and gim5b, are the predominant membrane proteins of the microbodies (glycosomes) of trypanosoma brucei. the compartmentation of glycosomal ... | 2003 | 12829709 |
| control of tsetse flies and trypanosomes using molecular genetics. | tsetse flies (diptera: glossinidae) are important agricultural and medical vectors transmitting the african trypanosomes, the agents of sleeping sickness disease in humans and various diseases in animals (nagana). while the prevalence of disease has increased to epidemic proportions, lack of a mammalian vaccine and affordable and effective drugs have hindered disease control. trypanosomiasis management relies heavily on the control of its single insect vector, the tsetse fly. despite the effecti ... | 2003 | 12878419 |
| gene expression level influences amino acid usage, but not codon usage, in the tsetse fly endosymbiont wigglesworthia. | wigglesworthia glossinidia brevipalpis, the obligate bacterial endosymbiont of the tsetse fly glossina brevipalpis, is characterized by extreme genome reduction and at nucleotide composition bias. here, multivariate statistical analyses are used to test the hypothesis that mutational bias and genetic drift shape synonymous codon usage and amino acid usage of wigglesworthia. the results show that synonymous codon usage patterns vary little across the genome and do not distinguish genes of putativ ... | 2003 | 12949182 |
| gpi transamidase of trypanosoma brucei has two previously uncharacterized (trypanosomatid transamidase 1 and 2) and three common subunits. | glycosylphosphatidylinositol (gpi) anchor is a membrane attachment mechanism for cell surface proteins widely used in eukaryotes. gpis are added to proteins posttranslationally by a complex enzyme, gpi transamidase. previous studies have shown that human and saccharomyces cerevisiae gpi transamidases are similar and consist of five homologous components: gaa1, gpi8, pig-s, pig-t, and pig-u in humans and gaa1p, gpi8p, gpi17p, gpi16p, and cdc91p in s. cerevisiae. we report that gpi transamidase of ... | 2003 | 12958211 |
| attenuation of virulence of trypanosoma brucei correlated with loss of salivary gland infection by a tsetse-fly. | | 1953 | 13077727 |
| [glossina morsitans and trypanosomiasis in southern mosso, urundi]. | | 1952 | 13092464 |
| [various aspects of the control of glossina morsitans west by control of game in the govuro region (southern save)]. | | 1952 | 13092467 |
| a new tsetse-fly from the british cameroons. | | 1955 | 13239085 |
| some observations on glossina morsitans ugandensis vanderplank in the sudan. | | 1955 | 13326571 |
| [determination of the feeding of glossina morsitans, west. in mutara (ruanda)]. | | 1956 | 13340491 |
| [means of action against glossina morsitans, west. in mutara (ruanda)]. | | 1956 | 13340492 |
| a preliminary account of the deposition by the tsetse-fly of the infective forms of trypanosoma rhodesiense, their subsequent migration to the general circulation, and their development to the blood forms. | | 1956 | 13363295 |
| the composition of tsetse-fly saliva. i. a histochemical analysis. | | 1956 | 13363297 |
| the composition of tsetse-fly saliva. ii. analysis of amino acids and sugars by paper partition chromatography. | | 1956 | 13363298 |
| the oxidative metabolism of african pathogenic trypanosomes. i. observations on trypanosoma rhodesiense maintained by sub-inoculation and cyclical tsetse-fly transmission. | | 1956 | 13380994 |
| studies on the deposition, migration, and development to the blood forms of trypanosomes belonging to the trypanosoma brucei group. i. an account of the process of feeding adopted by the tsetse-fly when obtaining a blood-meal from the mammalian host, with special reference to the ejection of saliva and the relationship of the feeding process to the deposition of the metacyclic trypanosomes. | | 1956 | 13395333 |
| an experiment on the infectivity to glossina morsitans of a strain of trypanosoma rhodesiense and of a strain of t. brucei, with some observations on the longevity of infected flies. | | 1957 | 13445073 |
| observations on laboratory colonies of the tsetse flies glossina morsitans west. and glossina austeni newstead. | | 1957 | 13504856 |
| detection of tsetse fly at night. | | 1958 | 13541481 |
| use of reflecting paints for locating tsetse fly at night. | | 1958 | 13541482 |
| [reports on the laboratory breeding of glossina morsitans west]. | | 1958 | 13627657 |
| [transmission of trypanosomes by glossina morsitans at mutara (ruanda)]. | | 1958 | 13627658 |
| [growth of glossina morsitans west. in the laboratory]. | | 1960 | 13685422 |
| seasonal changes in the breeding places of glossina morsitans morsitans westwood. | | 1961 | 13705936 |
| a test for drug-resistant trypanosomes in experimental tsetse-fly challenge of cattle. | | 1960 | 13785544 |