Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| sex separation of tsetse fly pupae using near-infrared spectroscopy. | implementation of the sterile insect technique for tsetse (glossina spp.) requires that only sterile male insects be released; thus, at some stage of the fly production process the females have to be removed. a further constraint in the use of the sterile insect technique for tsetse is that the females are needed for colony production and hence, a non-destructive method of sex separation is required. in most tsetse sterile insect technique programmes thus far, females have been eliminated from t ... | 2005 | 15960879 |
| experimental trypanosomiasis in yankasa ewes: the body weight response. | sleeping sickness (african trypanosomasis) is an anthropozoonosis transmitted primarily by the tsetse fly. it is associated with a host of clinical indices ranging from fever, aneamia and anorexia to reproductive failures in man and his domestic animals. the main objective of this study is to appraise the responsiveness of the body weight as a clinical indicator of sleeping sickness in experimentally infected yankasa ewes. twelve mature yankasa sheep (6 infected and 6 control ewes) were used in ... | 2004 | 15977439 |
| knowledge and attitudes of cattle owners regarding trypanosomosis control in tsetse-infested areas of uganda. | a pilot survey using a structured questionnaire was conducted in tororo and busia districts of uganda on the knowledge and attitudes of cattle owners regarding tsetse fly and trypanosomosis control, in order to understand factors that hindered their full participation. a total of 81 cattle owners was randomly selected and interviewed, of which 92.5% were aware of tsetse flies and trypanosomosis and 87.6% recognised animal trypanosomosis as a problem in the area. most cattle owners were aware of ... | 2004 | 15830601 |
| human african trypanosomiasis: clinical presentation and immune response. | human african trypanosomiasis or sleeping sickness is caused by infection with two subspecies of the tsetse-fly-vectored haemoflagellate parasite trypanosoma brucei. historically, epidemic sleeping sickness has caused massive loss of life, and related animal diseases have had a crucial impact on development in sub-saharan africa. after a period of moderately successful control during the mid-part of the 20th century, sleeping sickness incidence is currently rising, and control is hampered by a c ... | 2004 | 15771682 |
| mixed infections of trypanosomes in tsetse and pigs and their epidemiological significance in a sleeping sickness focus of côte d'ivoire. | in a sleeping sickness focus of côte d'ivoire, trypanosomes were characterized in humans, pigs and tsetse using various techniques. out of 74 patients, all the 43 stocks isolated by kivi (kit for in vitro isolation) appeared to belong to only one zymodeme of trypanosoma brucei gambiense group 1 (the major zymodeme z3). the only stock isolated on rodents belonged to a different, new, zymodeme (z50), of t. b. gambiense group 1. from 18 pigs sampled in the same locations as the patients, pcr showed ... | 2004 | 15648692 |
| a novel purine nucleoside transporter whose expression is up-regulated in the short stumpy form of the trypanosoma brucei life cycle. | purine nucleoside and nucleobase transporters play a vital role in the metabolism and survival of trypanosoma brucei because this parasitic protozoan is unable to synthesize purines de novo and thus must acquire preformed purines from its hosts. these parasites express a variety of nucleoside and nucleobase permeases with diverse substrate specificities and distinct patterns of expression during the trypanosome life cycle. we report here that expression of the newly characterized t. brucei nucle ... | 2004 | 15478805 |
| admixture and diversity in west african cattle populations. | we present a population genetic analysis of microsatellite variation in 16 west african cattle populations. west africa represents a unique juxtaposition of different climatic and ecological zones in a relatively small geographical area. while more humid coastal regions are inhabited by the tsetse fly, a vector which spreads trypanosomiasis among cattle, the disease is not transmitted in the drier areas outside this zone. this is the most thorough study of genetic diversity in cattle within this ... | 2004 | 15488005 |
| the macrocyclic lactone "spinosad," a promising insecticide for tsetse fly control. | the susceptibility of tsetse flies (diptera: glossinidae), glossina palpalis gambiensis (vanderplank), and g. m. morsitans (westwood) to topically applied spinosad, a mixture of insecticidal molecules from the actinomycete saccharopolyspora spinosa, is almost as high as to deltamethrin. however, susceptibility to spinosad does not differ significantly between teneral and gravid flies, contrary to deltamethrin. spinosad might be a promising candidate for future tsetse control by the sequential ae ... | 2004 | 15535607 |
| cloning and expression of the yolk protein of the tsetse fly glossina morsitans morsitans. | two major families of nutritional proteins exist in insects, namely the vitellogenins and the yolk proteins. while in other insects only vitellogenins are found, cyclorraphan flies only contain yolk proteins. possible sites of yolk protein synthesis are the fat body and the follicle cells surrounding the oocyte. we report the cloning of the yolk protein of the tsetse fly glossina morsitans morsitans, a species with adenotrophic viviparity. the tsetse fly yolk protein could be aligned with other ... | 2004 | 15544941 |
| cold shock and regulation of surface protein trafficking convey sensitization to inducers of stage differentiation in trypanosoma brucei. | transmission of a protozoan parasite from a vertebrate to invertebrate host is accompanied by cellular differentiation. the signals from the environment that trigger the process are poorly understood. the model parasite trypanosoma brucei proliferates in the mammalian bloodstream and in the tsetse fly. on ingestion by the tsetse, the trypanosome undergoes a rapid differentiation that is marked by replacement of the variant surface glycoprotein (vsg) coat with gpi-anchored ep and gpeet procyclins ... | 2004 | 15545633 |
| african trypanosome interactions with an in vitro model of the human blood-brain barrier. | the neurological manifestations of sleeping sickness in man are attributed to the penetration of the blood-brain barrier (bbb) and invasion of the central nervous system by trypanosoma brucei gambiense and trypanosoma brucei rhodesiense. however, how african trypanosomes cross the bbb remains an unresolved issue. we have examined the traversal of african trypanosomes across the human bbb using an in vitro bbb model system constructed of human brain microvascular endothelial cells (bmecs) grown o ... | 2004 | 15562595 |
| monitoring the susceptibility of glossina palpalis gambiensis and g. morsitans morsitans to experimental infection with savannah-type trypanosoma congolense, using the polymerase chain reaction. | teneral glossina palpalis gambiensis and g. morsitans morsitans (diptera: glossinidae) were fed on mice infected with savannah-type trypanosoma (nannomonas) congolense. the infection was monitored by checking the post-feeding diuresis fluid (midgut infection) and saliva (mature infection) of individual flies for parasites, at different times post-infection, using microscopical examination and a pcr-based assay. the results indicated that both tsetse species supported established midgut infection ... | 2004 | 15000728 |
| comparison of the infection rate of tsetse, glossina morsitans morsitans, fed in vitro or in vivo. | studies were made of infection rates of trypanosomes in the tsetse fly glossina morsitans morsitans westwood (diptera: glossinidae) when maintained in vivo (rabbits) or in vitro on high quality, gamma-irradiated, sterile defibrinated bovine blood, obtained from the entomology unit of the international atomic energy agency (iaea). for both trypanosoma congolense broden and t. b. brucei plimmer & bradford, in vitro maintenance significantly reduced the proportion of flies that developed mature met ... | 2004 | 15009448 |
| tsetse flies are attracted to the invasive plant lantana camara. | in tsetse both sexes feed exclusively on the blood of vertebrates for a few minutes every 2-3 days. tsetse flies seek cover from high temperatures to conserve energy and plants provide shelter for tsetse in all the biotopes they occupy. recently, tsetse have taken cover in plantations and under the invasive bush lantana camara that has invaded large areas of the tsetse fly belt of africa. flies from such refugia are implicated in sleeping sickness epidemics. in a wind tunnel we show that both fo ... | 2004 | 15037092 |
| the trypanosoma brucei cyclin, cyc2, is required for cell cycle progression through g1 phase and for maintenance of procyclic form cell morphology. | cyc2 is an essential pho80-like cyclin that forms a complex with the cdc2-related kinase crk3 in trypanosoma brucei. in both procyclic and bloodstream form t. brucei, knock-down of cyc2 by rna interference (rnai) led to an accumulation of cells in g(1) phase. additionally, in procyclic cells, but not in bloodstream form cells, cyc2 rnai induced a specific cell elongation at the posterior end. the g(1) block, as well as the posterior end elongation in the procyclic form, was irreversible once est ... | 2004 | 15039435 |
| inhibition of the dna amplification of trypanosomes present in tsetse flies midguts: implications for the identification of trypanosome species in wild tsetse flies. | the present study was carried out in order to investigate if there was really a failure of pcr in identifying parasitologically positive tsetse flies in the field. tsetse flies (glossina palpalis gambiensis and glossina morsitans morsitans) were therefore experimentally infected with two different species of trypanosoma (trypanosoma brucei gambiense or trypanosoma congolense). a total of 152 tsetse flies were dissected, and organs of each fly (midgut, proboscis or salivary glands) were examined. ... | 2004 | 15071836 |
| metabolic rate variation in glossina pallidipes (diptera: glossinidae): gender, ageing and repeatability. | despite the importance of metabolic rate in determining flight time of tsetse and in mediating the influence of abiotic variables on life history parameters (and hence abundance and distribution), metabolic rate measurements and their repeatability have not been widely assessed in these flies. we investigate age-related changes in standard metabolic rate (smr) and its repeatability, using flow-through respirometry, for a variety of feeding, gender and pregnancy classes during early adult develop ... | 2004 | 15121455 |
| characterization of a digestive carboxypeptidase from the insect pest corn earworm (helicoverpa armigera) with novel specificity towards c-terminal glutamate residues. | carboxypeptidases were purified from guts of larvae of corn earworm (helicoverpa armigera), a lepidopteran crop pest, by affinity chromatography on immobilized potato carboxypeptidase inhibitor, and characterized by n-terminal sequencing. a larval gut cdna library was screened using probes based on these protein sequences. cdna haca42 encoded a carboxypeptidase with sequence similarity to enzymes of clan mc [barrett, a. j., rawlings, n. d. & woessner, j. f. (1998) handbook of proteolytic enzymes ... | 2004 | 15128309 |
| surface sialic acids taken from the host allow trypanosome survival in tsetse fly vectors. | the african trypanosome trypanosoma brucei, which causes sleeping sickness in humans and nagana disease in livestock, is spread via blood-sucking tsetse flies. in the fly's intestine, the trypanosomes survive digestive and trypanocidal environments, proliferate, and translocate into the salivary gland, where they become infectious to the next mammalian host. here, we show that for successful survival in tsetse flies, the trypanosomes use trans-sialidase to transfer sialic acids that they cannot ... | 2004 | 15136592 |
| history of sleeping sickness (african trypanosomiasis). | infections with subspecies of the protozoan parasite trypanosoma brucei cause important wasting diseases in africa (nagana in cattle and sleeping sickness in humans). these diseases were little known until the end of the nineteenth century when serious epidemics of nagana were reported and raised concern among the colonial powers. the early history of sleeping sickness revolves around the discovery of the causative organism, its mode of transmission,and its life cycle in the tsetse fly. the hist ... | 2004 | 15145378 |
| a cross-sectional epidemiological survey of bovine trypanosomosis and its vectors in the savelugu and west mamprusi districts of northern ghana. | the epidemiology of bovine trypanosomosis was investigated in two districts (savelugu and west mamprusi) of northern ghana with different land use and environmental characteristics. the land use intensity and environmental change was suspected to be higher in the savelugu district. a cross-sectional entomological survey conducted along the white volta river and its tributaries confirmed the presence of only glossina palpalis gambiensis and g. tachinoides. the challenge index as measured by the p ... | 2004 | 15158552 |
| expression of a major surface protein of trypanosoma brucei insect forms is controlled by the activity of mitochondrial enzymes. | in cycling between the mammalian host and the tsetse fly vector, trypanosomes undergo major changes in energy metabolism and surface coat composition. early procyclic (insect) forms in the tsetse fly midgut are coated by glycoproteins known as ep and gpeet procyclins. ep expression continues in late procyclic forms, whereas gpeet is down-regulated. in culture, expression of gpeet is modulated by glycerol or glucose. here, we demonstrate that a glycerol-responsive element of 25 nucleotides within ... | 2004 | 15201340 |
| a study of host preference in tsetse flies using a modified heteroduplex pcr-based method. | a study of host preference in tsetse flies using a modified heteroduplex pcr-based method is described. domestic and wild animal blood samples were collected to extract the corresponding reference dnas. in campo (south cameroon), tsetse flies (mainly glossina palpalis palpalis) were trapped and 41 bloodmeals were collected. all reference dnas and 37 bloodmeal dnas (90.7%) were successfully amplified and hybridised. twelve bloodmeals (32.4%) were of human origin, 13 (35.4%) were from sitatunga (t ... | 2004 | 15234660 |
| the transmission of mixed trypanosoma brucei brucei/t. congolense infections by tsetse (glossina morsitans morsitans). | laboratory experiments and field observations clearly show that tsetse flies can be carriers of mixed trypanosome infections. question remains how easy it is for the tsetse fly to acquire such a mixed infection during the first bloodmeal. this is of particular importance in the epidemiology of trypanosoma brucei s.l., often a cryptic infection and difficult to transmit to non-teneral tsetse flies. to determine the transmission rate of t. brucei as part of a mixed infection, teneral glossina mors ... | 2004 | 14746974 |
| african labs win major role in tsetse-fly genome project. | 2004 | 14749791 | |
| mitochondrial diversity analysis of glossina palpalis gambiensis from mali and senegal. | west african riverine tsetse populations of glossina palpalis gambiensis vanderplank (diptera: glossinidae) were investigated for gene flow, inferred from mitochondrial diversity in samples of 69 flies from senegal and 303 flies from three river drainages in mali. four polymorphic mitochondrial loci were scored. mean haplotype diversities were 0.30 in mali, 0 in senegal and 0.18 over both mali and senegal. these diversities estimate the probabilities that two randomly chosen tsetse have differen ... | 2004 | 15347397 |
| abdominal pericardial sinus: a neurohemal site in the tsetse and other cyclorraphan flies. | an ultrastructural study of the heart of the tsetse fly, glossina morsitans, and of several other species of cyclorraphan flies revealed that the ventral region of the heart of adult flies is supported by a muscular septum not present in the larval stage. the pericardial septum of the adult heart is composed laterally of alary muscles and a central longitudinal muscle that extends the length of the abdominal aorta, whereas the larval heart is supported ventrally only by alary muscles and strands ... | 2003 | 14765650 |
| partial characterisation of a trypanosome-lysing factor from the midgut of the desert locust, schistocerca gregaria. | screening and biochemical characterisation of trypanosome-lysing factor (trypanolysin) from non-vector insect, schistocerca gregaria. | 2003 | 15248675 |
| monitoring the developmental status of trypanosoma brucei gambiense in the tsetse fly by means of pcr analysis of anal and saliva drops. | teneral glossina palpalis gambiensis (diptera: glossinidae) were infected with a culture of procyclic forms of trypanosoma brucei gambiense using a single-bloodmeal membrane feeding technique. the infection was monitored by analysing the saliva (mature infection) and anal drop (midgut infection) of each fly at different post-infection times both by microscopic observation and polymerase chain reaction (pcr). amplification revealed many more positive anal drops than microscopy. the monitoring sho ... | 2003 | 14516928 |
| adult midgut expressed sequence tags from the tsetse fly glossina morsitans morsitans and expression analysis of putative immune response genes. | tsetse flies transmit african trypanosomiasis leading to half a million cases annually. trypanosomiasis in animals (nagana) remains a massive brake on african agricultural development. while trypanosome biology is widely studied, knowledge of tsetse flies is very limited, particularly at the molecular level. this is a serious impediment to investigations of tsetse-trypanosome interactions. we have undertaken an expressed sequence tag (est) project on the adult tsetse midgut, the major organ syst ... | 2003 | 14519198 |
| cleavage of trypanosome surface glycoproteins by alkaline trypsin-like enzyme(s) in the midgut of glossina morsitans. | ep and gpeet procyclin, the major surface glycoproteins of procyclic forms of trypanosoma brucei, are truncated by proteases in the midgut of the tsetse fly glossina morsitans morsitans. we show that soluble extracts from the midguts of teneral flies contain trypsin-like enzymes that cleave the n-terminal domains from living culture-derived parasites. the same extract shows little activity against a variant surface glycoprotein on living bloodstream form t. brucei (mitat 1.2) and none against gl ... | 2003 | 14527515 |
| [new data on parasitization of glossina palpalis palpalis (diptera: glossinidae) by hexamermis glossinae (nematoda: mermithidae) in a forested area of ivory coast]. | observations on the parasitism of glossina palpalis palpalis by hexamermis glossinae were carried out over a period of one year by catching flies at abengourou, aboisso and daloa (forested area of ivory coast). no parasite is observed out of 2,168 glossina palpalis palpalis caught in abengourou and 9,732 in aboisso. at daloa, dissections of 7,341 glossina reveal 1.75% parasited flies. all the worms were located in the abdominal cavity, loosely intertwined with the internal organ. males were more ... | 2003 | 14535167 |
| proventriculus (cardia) plays a crucial role in immunity in tsetse fly (diptera: glossinidiae). | fat body and hemocytes play a central role in cellular and humoral responses for systemic infections in invertebrates, similar to the mammalian liver and blood cells. epithelial surfaces, in particular the midgut, participate in the initial local immune responses in order to aid in the generation of the terminal cytotoxic molecules that mediate non-self recognition. here, we describe for the first time the immune responses of a cluster of cells at the foregut/midgut junction--known as proventric ... | 2003 | 14563366 |
| comparative genomics of insect-symbiotic bacteria: influence of host environment on microbial genome composition. | commensal symbionts, thought to be intermediary amid obligate mutualists and facultative parasites, offer insight into forces driving the evolutionary transition into mutualism. using macroarrays developed for a close relative, escherichia coli, we utilized a heterologous array hybridization approach to infer the genomic compositions of a clade of bacteria that have recently established symbiotic associations: sodalis glossinidius with the tsetse fly (diptera, glossina spp.) and sitophilus oryza ... | 2003 | 14602646 |
| local skin reaction (chancre) induced following inoculation of metacyclic trypanosomes in cattle by tsetse flies is dependent on cd4 t lymphocytes. | the first visible response in livestock to the bite of a trypanosome-infected tsetse fly is the formation of a localized skin reaction, also known as a chancre. this is an inflammatory response in the skin associated with swelling and an influx of cells. it is thought to be associated with an acquired immune response to the injected metacyclic trypanosomes. in this study, we examined the role of t lymphocytes in the development of the inflammatory response, by depleting cattle of t cell subpopul ... | 2003 | 14651588 |
| the effect of age on the mating competitiveness of male glossina fuscipes fuscipes and g. palpalis palpalis. | the effect of age on male glossina fuscipes fuscipes, newstead, and glossina palpalis palpalis, austin (diptera: glossinidae) competiveness were investigated with a view to estimate optimal age for sterile male release. sterile insect technique involves the mass production, sterilization and sequential release of males of the target species to out compete the wild male population. mating between released sterile males and wild females produce inviable progeny and the population is reduced over s ... | 2003 | 15841229 |
| characterization of microsatellite markers in the tsetse fly, glossina pallidipes (diptera: glossinidae). | glossina pallidipes is a vector of african trypanosomiasis. here we characterize eight new polymorphic microsatellite loci in 288 g. pallidipes sampled from 12 kenya populations. the number of alleles per locus ranged from four to 36 with a mean of 20.5 +/- 10.1. expected single locus heterozygosities varied from 0.044 to 0.829. heterozygosity averaged 0.616 +/- 0.246. no linkage disequilibrium was found. we also report results in eight other tsetse species estimated by using the primers develop ... | 2003 | 16718306 |
| 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 |
| 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 |
| [reproductive disorders in glossina palpalis palpalis (diptera: glossinidae) in forested areas of ivory coast]. | study of reproductive disorders were carried out through the dissection of 11,012 tsetse flies caught over a period of one year in forested different habitats of glossina palpalis palpalis of daloa in ivory coast. the proportion of females with reproductive disorders was very low and estimated at 0.79%. out of 87 tsetse files with reproductive disorders, 93.10% were abortions, 5.77% were ovular blockage and 1.13% was uterine pupaison. reproductive disorders were recorded from all age groups: 0.7 ... | 2003 | 12847927 |
| 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 |
| estimating tsetse population parameters: application of a mathematical model with density-dependence. | a density-dependent model is used to describe the dynamics of an open population of tsetse flies (diptera: glossinidae). immigration (or emigration) takes place when the total population is below (or above) a biologically determined threshold value. the population is also subjected to birth and death rates, as well as to the risk of being trapped (continuously or intermittently). during trapping the population decreases toward a 'low' equilibrium population and when trapping ceases the populatio ... | 2003 | 12941011 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| microsatellite polymorphism in tsetse flies (diptera: glossinidae). | in sub-saharan africa, tsetse flies are the vectors of trypanosomes, the causative agents of sleeping sickness in humans and nagana in animals. certain wild populations of the palpalis group exhibit intraspecific variation and are suspect of manifest differences in vectorial capacity. the current study reports the identification of 13 polymorphic microsatellite loci from glossina palpalis palpalis robinean-desvoidy. the majority of these markers amplify corresponding loci from the related specie ... | 2001 | 11372961 |
| 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 |
| 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 |
| 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 |
| slender and stumpy bloodstream forms of trypanosoma brucei display a differential response to extracellular acidic and proteolytic stress. | natural infections of mammals with african trypanosomes, such as trypanosoma brucei, are generally pleomorphic, the population consisting of different forms, termed slender and stumpy forms, that vary in number as the parasitaemia develops. we show that the differentiation of slender into stumpy forms is characterized by the acquisition by the parasite of the ability to regulate its internal ph, even in the face of a large, inwardly directed gradient of h+, as well as a tolerance towards externa ... | 2000 | 10601846 |