| complement activating factor(s) of trypanosoma lewisi: some physiochemical characteristics of the active components. | of the complement activating factors present in trypanosoma lewisi, the major component, a carbohydrate containing substance was further investigated. this component was found to have a lag time of complete activation of 2 ch50 units of bovine complement of approximately 15 minutes while 1% trypsin (a known activator of complement, used as a control system) was capable of instant consumption of a similar quantity of complement. in addition, the complement activating factor of trypanosomes was ob ... | 1978 | 25701 |
| ablastin in trypanosoma lewisi and related phenomena in other species of trypanosomes. | | 1975 | 54264 |
| the ablastin phenomenon: inhibition of membrane function. | | 1975 | 54265 |
| crossed immunoelectrophoretic analyses of antigens from trypanosoma lewisi and trypanosoma musculi. | | 1979 | 94319 |
| initial characterization of trypanosoma lewisi surface membrane antigen. | the purified t. lewisi were subjected to hypotonic lysis plus freezing and thawing in acetone dry ice bath. the trypanosome ghosts were obtained after repeated washing and centrifugation. the homogenized ghost suspension was assayed for enzyme na++k+ atpase activity to ratify the presence of the trypanosome surface membrane. membrane solubilized in sodium dodecyl sulfate were fractionated by gel filtration on sephadex columns equilibrated with the detergent and electrophoresis in polyacrylamide ... | 1978 | 212837 |
| trypanosoma lewisi, t. acomys and t. cruzi: a method for their cultivation with mammalian tissue. | | 1977 | 320031 |
| trypanosoma lewisi: immunoelectron microscopic studies on the surface antigens of bloodstream forms. | | 1977 | 330184 |
| trypanosoma lewisi: characterization of complement-activating components. | | 1977 | 330186 |
| activation of complement by trypanosomes. | factors exhibiting anti-complementary activity released from trypanosomes after incubation at 20 degrees c were described. the active material was shown to consume the first component of bovine complement. while the anti-complementary factor(s) from t. lewisi could activate bovine, human and guinea pig complement, the factor(s) from t. congolense was observed to activate bovine complement, but not guinea pig and only slightly human complement. the roles of complement activating factor(s) of tryp ... | 1977 | 330194 |
| [antitumor activity of fatty acid derivatives isolated from protozoa]. | water-soluble monoethers of sucrose and fatty acids were obtained from trypanosoma lewisi and astasia longa. the maximum tolerated dose of the preparations on their single intraperitoneal administration was more than 25 g/kg. the doses of 10--40 mg/kg were used repeatedly in therapy. carcinoma 755, lewis carcinoma, sarcoma 45, sarcoma 37 and sarcoma 180 were sensitive to the preparations. the preparations were inactive against experimental leukemia. | 1977 | 334051 |
| iron metabolism in trypanosoma lewisi infection: serum iron and serum iron-binding capacity. | progressive changes in iron levels, total iron binding capacity and hematocrit values in sera of rats infected with trypanosoma lewisi are described. the host dietary group were: (1) complete or full complement; (2) iron-deficient, and (3) pair-fed or calorically restricted. the hematocrit values of t. lewisi-infected rats given the various diets were not significantly different from those of the controls. the decrease in total iron binding capacity (tibc) of rats inoculated with t. lewisi and f ... | 1977 | 335688 |
| haemoflagellates: commercially available liquid media for rapid cultivation. | the successful cultivation of a variety of haemoflagellates in three different liquid media is reported. these media include medium 199, grace's insect tissue-culture medium and schneider's drosophila medium, each in combination with 30% (v/v) foetal calf serum. these media were used to cultivate old and new world species of visceral and cutaneous human leishmania, as well as leishmania species isolated from sandflies, rodents, and reptiles. four strains of trypanosoma cruzi, an isolate of t. r- ... | 1978 | 351527 |
| changes in the activity of the reticulo-endothelial system of rats during an infection with t. lewisi. | data presented show that during the course of a trypanosoma lewisi infection in rats there was both an activation of the phagocytic cells of the liver and spleen and an increase in their numbers. there was a marked lymphoid hyperplasia in the white pulp of the spleen with an increase in the number and size of the lymphoid follicles. degenerative changes occurred in the liver parenchymal cells during the infection, and at certain stages large numgers of mononuclear cells were observed in the vasc ... | 1978 | 352324 |
| anemia, splenomegaly, and glomerulonephritis associated with autoantibody in trypanosoma lewisi infections. | anemia with splenomegaly and signs of glomerulonephritis were found associated with the acute and post-acute phase of trypanosoma lewisi infections of laboratory rats. the onset of the anemia was associated with the peak of parasitemia and the development of cold-active hemagglutinin (ha) for trypsinized rat erythrocytes. it persisted with gradual recovery for as long as the trypanosomes and ha were detected in the blood. signs of glomerulonephritis consisted of hypercellularity of the glomerula ... | 1978 | 355613 |
| [effect of lipid preparations isolated from protozoa on experimental leishmaniasis in golden hamsters]. | the effect of lipid preparations nos. 59 and 60 isolated from protozoa on experimental leishmaniosis of golden hamsters was studied. preparations nos. 59 and 60 are water-soluble derivatives of fatty acids isolated from trypanosoma lewisi and astasia longa respectively. it was found that both preparations administered to the animals simultaneously with the causative agent or after formation of the leishmaniosis infiltrates inhibited the development of the disease clinical signs. such an effect o ... | 1978 | 363050 |
| circadian rhythms of trypanosoma congolense in laboratory rodents. | | 1978 | 366815 |
| the role of the macrophage in immunity to trypanosoma lewisi infections in the rat. | | 1979 | 371817 |
| a method for the assay of ablastin in the serum of rats infected with trypanosoma lewisi. | this paper describes a simple quantitative assay for albastin, a factor present in the serum from rats infected with trypanosoma lewisi, which prevents the division of the parasite. the assay measures in vitro the inhibition of the incorporation of 3h-tdr into the dna of t. lewisi in the presence of serum from infected animals. utilising this method, one can measure the titre of albastin in a particular serum sample and the time and duration of its appearance in the circulation of infected rats. | 1978 | 378207 |
| trypanosoma lewisi: alterations in membrane function in the rat. | | 1979 | 378677 |
| effects of lysozyme on trypanosoma lewisi. | daily lysozyme (hen egg) injections, beginning on day 6 of trypanosoma lewisi infections in rats, significantly reduced the number of circulating trypanosomes. the effect was dose dependent. maximum reduction (50%) occurred 24 hours after one treatment of 80 mg was given intraperitoneally (i.p.). the same dose of lysozyme was more effective when divided equally into two injections per day. controls consisting of appropriate buffers as well as human serum albumin had no effect on trypanosome popu ... | 1979 | 394664 |
| trypanosoma lewisi: accumulation of antigen-specific host igg as a component of the surface coat during the course of infection in the rat. | | 1979 | 376326 |
| unusual antibody-induced modulation of surface antigens in the cell coat of a bloodstream trypanosome. | unlike other eukaryotic cells, trypanosoma lewisi forms caps at 0 degrees c when incubated with rabbit immunoglobulin g(igg) directed against surface igg from the rat host. the host igg, which is specific for parasite antigens, probably does not cause capping of these antigens in vivo, since trypanosomes treated with fab fragments directed against rat igg are uniformly labeled and do not cap at 0 degrees c or 37 degrees c. | 1978 | 356265 |
| in vitro antitrypanosomal activity of certain alkaloids against trypanosoma lewisi. | | 1976 | 798093 |
| characterization of trypanosomes by gc base composition: isolation of trypanosomal dna by two methods. | | 1976 | 798377 |
| trypanosoma lewisi and t. cruzi: effect of infection on gestation in the rat. | | 1975 | 804411 |
| complement in experimental trypanosoma lewisi infection of rats. | the role of complement in host resistance to infection with trypanosoma lewisi was studied in normal, c4-deficient, and c3-depleted rats. complement levels were measured in normal rats throughout the course of infection. a drastic reduction of total complement and c4 hemolytic activities occurred, and c3 levels measured immunochemically were decreased. although total complement and c4 levels were regularly reduced to less than 10% of preinfection levels regardless of parasite numbers, the degree ... | 1976 | 825467 |
| the generation and identification of the hemolysin of trypanosoma congolense. | the hemolytic activity of trypanosoma congolense appears to be due to the presence of free fatty acids generated by the action of phospholipase a on endogenous phosphatidyl choline. some lysolecithin also contributes to the lytic activity. trypanosoma lewisi, being devoid of phospholipase a, does not generate free fatty acids and is therefore non-hemolytic. | 1977 | 891767 |
| survival of aegyptianella pullorum, anaplasma marginale and various parasitic protozoa following prolonged storage in liquid nitrogen. | various protozoa species were examined using in vivo and in vitro methods to determine their ability to survive prolonged periods of storage in liquid nitrogen. the following protozoan species were successfully recovered after they had been cryopreserved for a period over 10 years: trypanosoma lewisi, t. cruzi, t. congolense, t. brucei, t. rhodesiense, t. gambiense, t. evansi, t. equinum, t. equiperdum, leishmania donovani, plasmodium berghei, p. praecox (relictum), babesia rodhaini and b. canis ... | 1977 | 919686 |
| physiological relationships and circadian periodicities in rodent trypanosomes. | trypanosome circadian rhythms in rats infected with trypanosoma lewisi and mice infected with t. duttoni (equals t. musculi) were observed. peak numbers of trypanosomes were recorded at nightfall and fewest organisms seen at daybreak. reversal of the photoperiod resulted in a comparable reversal of the trypanosome parasitaemia. periodicities of blood glucose levels and circulating leucocytes were relatively similar in t. lewisi-infected rats to rhythms previously defined in normal aimals. in try ... | 1976 | 982519 |
| evidence implicating the mononuclear phagocytic system of the rat in immunity to infections with trypanosoma lewisi. | the present study emphasises the importance of the mononuclear phagocytic system of the rat in immunity to infections with trypanosoma lewisi. despite the great increase in the weight of the spleen, the liver played a major role in removing the parasites from the circulation. no evidence could be obtained that removal of the parasites was related to the lytic activity of specific antibody and complement. | 1978 | 354628 |
| direct activation of complement by trypanosomes. | | 1978 | 351160 |
| [isolation and physico-chemical properties of a complex kinetoplast dna associate from the cells of trypanosoma lewisi]. | an associate of kinetoplast dna (k-dna) was isolated from the cells of trypanosoma lewisi and characterized in terms of its sedimentation properties, melting parameters and reassociation kinetics. electron microscopy studies showed that k-dna isolated is a complex associate of circular molecules. the contour length of minicircular molecules is 0.77 mkm. k-dna contains sites enriched by at-pairs; melting of native associate and k-dna fragments in the presence of 6.5 m sodium perchlorate results i ... | 1978 | 350297 |
| the generation of phospholipase a and hemolytic fatty acids by autolysing suspensions of trypanosoma congolense. | when t. congolense undergoes autolysis there is a concomitant appearance of phospholipase a activity and hemolytic fatty acids. the generation of enzyme activity is exponential, and the appearance of hemolytic activity corresponds to a free fatty acid concentration of 0.02 to 0.03 mg. per ml. the concentration of the trypanosome suspension markedly affected the kinetics of the generation process. in contrast, the autolysis of t. lewisi did not generate hemolytic activity unless exogenous phospho ... | 1978 | 347651 |
| trypanosoma lewisi: effects of immunosuppression on the serological reactivities of exoantigens and cellular antigens of bloodstream parasites. | | 1978 | 342268 |
| trypanosoma lewisi, trypanosoma rhodesiense: mitotic activity in normal and folic acid deficient rats. | ten experiments were performed to compare mitotic activity in livers of rats infected with trypanosoma rhodesiense and trypanosoma lewisi. the host dietary groups were: (1) complete of full complement; (2) folic acid deficient, and (3) pair-fed or calorically restricted. liver mitotic counts of t. lewisi-infected rats fed complete and pair-fed control diets showed a high degree of significance over that of control rats. from days 35 to 55, liver mitotic counts of t. lewisi-infected rats deficien ... | 1975 | 1103497 |
| trypanosoma lewisi: ultrastructural observations of surface antigen movement induced by antibody. | | 1978 | 342267 |
| increased susceptibility of trypanosoma lewisi infected, or decomplemented rats to salmonella typhimurium. | rats infected with trypanosoma lewisi or decomplemented by injection of cobra venom factor or complement activating factor of trypanosomes were found to be more susceptible to infection with salmonella typhimurium. decomplemented rats subsequently infected with t. lewisi developed higher blood parasitemia than did normal t. lewisi infected rats. | 1978 | 340247 |
| trypanosoma lewisi: body weight gains and food consumption of riboflavin-deficient rats given living cells, cell homogenates and cell metabolic products. | | 1975 | 236874 |
| conversion of dihydroorotate to orotate in parasitic protozoa. | the conversion of dihydroorotate to orotate, one of the key reactions in the de novo pyrimidine biosynthetic pathway, has been studied in a number of parasitic protozoa. enzyme activities capable of carrying out this reaction were detected in six members of the kinetoplastida (trypanosoma brucei, trypanosoma congolense, trypanosoma vivax, trypanosoma lewisi, trypanosoma cruzi, leishmania enriettii) and three members of the genus plasmodium (p. knowlesi, p. berghei, p. gallinaceum). the mechanism ... | 1979 | 217438 |
| adenosine 3',5'-monophosphate in reproducing and differentiated trypanosomes. | trypanosoma lewisi, a blood protozoan of rats, undergoes differentiation from a rapidly reproducing form to a nonreproducing form in response to the host antibody ablastin. intracellular concentrations of adenosine 3',5'-monophosphate (cyclic amp), which has been implicated in controlling reproduction in cultured mammalian cells, was measured in the two developmental forms of t. lewisi. the concentrations were significantly different, and the results support a hypothesis under which ablastin sti ... | 1975 | 171773 |
| human and animal trypanosomiases as world public health problems. | | 1979 | 117460 |
| surface immunoglobulins, a possible mechanism for the persistence of trypanosoma lewisi in the circulation of rats. | the results presented below show that the dividing and adult forms of t. lewisi share common antigens and indicate that the persistence of adult forms in the circulation of rats immune to reinfection is not due to a change in surface antigens as has been postulated. using a rabbit anti-rat immunoglobulin serum, the presence of rat immunoglobulins on the surface of adult trypanosomes could be demonstrated. these immunoglobulins were not complement-fixing or opsonic. it is suggested that these imm ... | 1977 | 71894 |
| interaction of nutrition and infection: effect of copper deficiency on resistance to trypanosoma lewisi. | the copper-deficient rat-trypanosome system was used to study copper deficiency in sprague dawley rats infected with trypanosoma lewisi. throughout the observational period, animals on the deficient diet had lower plasma and liver copper concentrations compared with complete and pair-fed animals. in all dietary groups, the food intake and body weight changes of rats inoculated with t lewisi showed significant increases over the noninoculated controls. the rate of these indices were significantly ... | 1992 | 1507261 |
| the relation of agglutinins to antigenic variation of trypanosoma lewisi. | during the course of infection in the rat, trypanosoma lewisi produces 2 antigenic variants: the 1st represents the initial, reproducing population of cells; and the 2nd the nonreproducing, ablastin-inhibited adult population. the specificities of the agglutinins elicited by the variants were studied by adsorption and agglutination methods and the newer immunoelectroadsorption technic. it was found that the reproducing variant has a surface antigen that reacts with the agglutinin specific for th ... | 1976 | 58989 |
| immunologic and fine structure evidence of avidly bound host serum proteins in the surface coat of a bloodstream trypanosome. | intact, washed trypanosoma lewisi bloodstream forms, isolated from rats, were agglutinated specifically by antisera against rat whole serum, albumin, alpha2-macroglobulin, and igg. however, trypsinized bloodstream and intact culture forms lacking surface coat were not agglutinated by these antisera. trypsinized bloodstream forms, incubated in dilute rat or heterologous host serum proteins, were agglutinated with specific antisera. the characteristic surface coat of intact bloodstream forms was a ... | 1976 | 57618 |
| cell surface saccharides of trypanosoma lewisi. i. polycation-induced cell agglutination and fine-structure cytochemistry. | trypanosoma lewisi bloodstream and culture forms were agglutinated differentially with low concentrations of the cationic compounds: ruthenium red, ruthenium violet, alcian blue chloride, 1-hexadecylpyridinium chloride, lanthanum chloride, and cationized ferritin. the bloodstream form trypanosomes gave the highest agglutination levels with each of the compounds tested. ruthenium red was the most effective inducer of cell agglutination among the several cations used. trypsin-treated bloodstream f ... | 1975 | 54363 |
| ultracytochemistry of the surface coat/pellicle complex in trypanosoma brucei. | ultracytochemistry of polysaccharides and specific sugar residues reveals differences in the surface staining pattern between developmental forms of trypanosoma brucei. the techniques used were the pa (periodic acid)-tch (thiocarbohydrazide)-silver albumose reaction for the polysaccharides, and the concanavalin a (con a)-perioxdase-dab coupling method for specific sugar residues. blood and metacyclic forms, both possessing a surface coat, stain distinctly for carbohydrates at the level of the pe ... | 1975 | 51580 |
| presence and properties of thymidylate synthase in trypanosomatids. | high speed centrifugal supernatant fractions of homogenates of a number of trypanosomatids were assayed for thymidylate synthase (5,10-methylene-tetrahydrofolate: dump c-methyltransferase, ec 2.1.1.45) activity using the method of lomax and greenberg (1967) j. biol. chem. 242, 109-113). similar activities were detected in crithidia fasciculata, crithidia oncopelti, the blood forms of trypanosoma brucei, trypansoma congolense and trypanosoma lewisi and the blood, intracellular and culture forms o ... | 1977 | 14696 |
| a culture and biochemical assay system for trypanosoma lewisi. | | 1976 | 786706 |
| the effect of bacterial adjuvants on trypanosoma lewisi infections in rats. | the effect of escherichia coli endotoxin, b.c.g. vaccine and bordetella pertussis vaccine on the parasitemia of trypanosoma lewisi was studied in rats. it was found that in general, b. pertussis administration resulted in higher and more prolonged parasitemias than normal. in contrast e. coli endotoxin tended to reduce both the intensity and duration of parasitemia. possible reasons for this phenomenon are discussed. | 1975 | 770268 |
| [case of the transmission of the rat trypanosome by lice]. | data are given on the laboratory spontaneous occurrence of trypanosomiasis in young rats. it was demonstrated that the louse polyplax spinulosa is the main mechanical vector of trypanosoma lewisi. unlike the case of the real host, the flea, the trypanosomes do not undergo the whole developmental cycle in the louse. | 1978 | 704144 |
| antibody to fibrinogen/fibrin products (anti-f) in malaria, babesiosis, and trypanosomiasis of rodents. | antibody to fibrinogen/fibrin related products (anti-f) was stimulated during the course of plasmodium chabaudi, babesia rodhaini, and trypanosoma lewisi infections in rats. titers of this autoantibody remained elevated in serum from rats that had recovered from each of the infections. column chromatographic studies indicated that anti-f was a 19s globulin, possibly igm. during acute infections high titers of anti-f were associated with elevated titers of cold-active hemagglutinin (cah) and immu ... | 1979 | 480072 |
| [histones from trypanosoma lewisi nuclei]. | a preparation of total histones has been isolated for the first time from the purified fractions of t. lewisi cell nuclei and characterized in terms of its chemical composition and rna-polymerase activity. a special attention during the isolation procedure was given to the repression of proteolytic degradation of the histones. the amount of protein in the chromatin is equivalent to that of dna. the amino acid composition and heterogeneity of the protein during polyacrylamide gel electrophoresis ... | 1979 | 389296 |
| cell surface saccharides of trypanosoma lewis i. ii. lectin-mediated agglutination and fine-structure cytochemical detection of lectin-binding sites. | bloodstream (bsf) and culture forms (cf) of trypanosoma lewisi were specifically agglutinated with the plant lectins concanavalin a (con a), soybean agglutinin (sba), wheat germ agglutinin (wga), and fucose-binding protein (fbp). lectin-mediated cell agglutination was inhibited, and reversed in the presence of specific lectin-binding saccharides. cells were agglutinated randomly with all lectins suggesting a uniform distribution in the trypanosome cell surface of the lectin-binding saccharide li ... | 1976 | 789385 |
| trypanosoma lewisi: comparative activity of a feral isolate in two strains of rats assessed by measurement of cell population, reproductive development and respiratory activity. | | 1978 | 372106 |
| cell volume and dna content of trypanosoma lewisi and t. mega in vitro. | two species of trypanosomes were harvested at a comparable stage in vitro development, just as cell division was ceasing and cell length had become maximal and its variability minimal. at this stage, t. mega displayed both a larger cell volume than t. lewisi (27.5 vs. 14.3 mu-2) and a greater dna content (0.23 vs. 0.048 pg/cell). | 1975 | 1092829 |
| trypanosoma lewisi: immunohematopoietic interrelationships of the infection in normal, hypoxic, and rebound animals. | | 1975 | 1097262 |
| a general survey of blood and tissue parasites of some rodents in arbil province, iraq. | in a survey of blood and tissue parasites from 233 mice and rats, consisting of 105 specimens of house mice (mus musculus), 99 black rats (rattus rattus), and 29 norway rats (rattus norvegicus), collected from different localities of arbil province, northern iraq, trypanosoma lewisi was found in 7 (7.07%) of 99 r. rattus and in 5 (17.86%) of 29 r. norvegicus, while trypanosoma musculi was found in 4 (3.80%) of 105 m. musculus and this is the first record of this trypanosome from rodents in iraq. ... | 1988 | 3052538 |
| [comparative morphological studies on the kinetoplast of various species of trypanosomes, with special reference to trypanosoma cruzi (author's transl)]. | comparative electron microscope studies on the morphology of the kinetoplast dna (k-dna) of the epimastigotes in many trypanosome species were carried out under standardized conditions. the k-dna shows a morphological variation during the cell cycle of culture forms of the trypanosome species under study. in longitudinal sections of the kinetoplast, the k-dna of t. cruzi appears as a compact trabecular structure; as a relatively disaggregated unit, with a central band or in a transitional stage ... | 1975 | 1099748 |
| [effect of citrate on the lipid makeup of trypanosoma lewisi under active aeration conditions]. | | 1975 | 1100699 |
| rat liver alcohol dehydrogenase isozymes: influence of infection with trypanosoma. | a study has been made of changes in alcohol dehydrogenase (adh) isozymes in livers of rats infected with the following trypanosomes: trypanosoma cruzi, t. rhodesiense, t. congolense, and six geographical isolates of t. lewisi. a control group of the same age was injected with saline, and another left uninjected. liver homogenates were electrophoresed in noble agar gels followed by formazan staining according to the method of ursprung and leone (1965). of a total of 25 replicates, 15 showed that ... | 1975 | 1101546 |
| physicochemical properties of kinetoplast dna from crithidia acanthocephali. crithidia luciliae, and trypanosoma lewisi. | the protozoa crithidia and trypanosoma contain within a mitochondrion a mass of dna known as kinetoplast dna (kdna) which consists mainly of an association of thousands of small circular molecules of similar size held together by topological interlocking. using kdna from crithidia acanthocephali, crithidia luciliae, and trypanosoma lewisi, physicochemical studies have been carried out with intact associations and with fractions of covalently closed single circular molecules, and of open single c ... | 1975 | 1104639 |
| ablastin: the phenomenon. | | 1975 | 1107050 |
| trypanosoma lewisi: effects of trace metal contaminants on immunological responses. | the effects of trace metal contaminants (lead, cadmium, and mercury) on the immunologic responses of rats infected with trypanosoma lewisi were investigated to determine whether chronic exposures to subclinical levels of these metals have adverse effects on the host's ability to respond to an infective agent.earlier and higher levels of parasitemia were detected in animals exposed to cadmium, lead, and mercury. the variability in length of trypanosome cells in metal-exposed animals became consta ... | 1988 | 3150464 |
| ablastin: antigen tolerance and lack of ablastin control of trypanosoma musculi during host's pregnancy. | | 1975 | 1107051 |
| nutritional and immunological factors in the control of infections with trypanosoma lewisi. | | 1975 | 1107053 |
| whence comes trypanosoma lewisi antigen which induces ablastic antibody: studies in the occult? | | 1975 | 1107054 |
| cellular responses to culture-derived soluble exoantigens of trypanosoma lewisi. | soluble exoantigens of trypanosoma lewisi were obtained from short-culture systems of dividing epimastigotes and non-dividing trypomastigotes incubated in phosphate-buffered saline glucose solution (pbsg) for 3 h at 37 degrees c. suppression of normal rat-spleen cell responses to mitogen concanavalin a (con a) occurred at high exoantigens concentrations. the epimastigote-derived exoantigens were more suppressive than the trypomastigote-derived exoantigens. the suppression of con a stimulation wa ... | 1992 | 1409532 |
| in vitro study of anticancer acridines as potential antitrypanosomal and antimalarial agents. | the requirement for rational drug design in the search for new agents that are active against parasitic protozoa prompted our in vitro studies with a group of 9-anilinoacridines. in vitro growth assays with trypanosoma lewisi identified a series of c-1' alkylaminoacridines which possess previously unreported potent growth-inhibitory activities against t. lewisi at a concentration range of 0.1 to 1 microm. in contrast, several 9-anilinoacridines that possess acridine ring nh2 substituents at c-3 ... | 1992 | 1416846 |
| trypanocidal drugs and their effect on parasitaemia, specific igg production and protective immunity in rats infected with trypanosoma lewisi. | in rats infected with trypanosoma lewisi, parasitaemia normally resolves by day 32; thereafter, the rodents become solidly immune to re-infection. rats treated on day 5 of infection with a single i.m. dose of 35 mg/kg of the trypanocidal drug ethidium bromide (eb) had recovered from parasitaemia by day 12, whereas berenil (be) given at 100 mg/kg, more than twice the recommended dose, had no effect on parasitaemia. however, rats treated for 4 consecutive days beginning on day 5 of infection with ... | 1992 | 1589433 |
| immune responses of germfree mice to experimental infection with trypanosoma cruzi. | 1. the immune responses to trypanosoma cruzi infection of germfree mice were compared to the responses of infected conventional mice. two groups (40 animals in each group) of 2-month old female cfw germfree and conventional mice were used. the igm and igg which bound to the surface of t. cruzi epimastigotes determined by elisa were significantly lower in germfree than in conventional mice (1/3 and 1/5 for igm and igg, respectively). 2. after infection there was a three-fold increase in the circu ... | 1991 | 1843873 |
| a surface glycoprotein of trypanosoma lewisi binds immunoglobulin g from the serum of uninfected rats. | detergent extracts of whole trypanosoma lewisi were fractionated by polyacrylamide gel electrophoresis and transferred to nitrocellulose for immunoblotting analysis. antibody probes to rat immunoglobulin g (igg) and igm detected intact gamma chains, mu chains, and light chains in extracts. the amount of immunoglobulin detected increased as the infection progressed. transfers were also incubated in serum from conventionally reared (crs), specific-pathogen-free (spfs), or germ-free rats before bei ... | 1986 | 3525414 |
| flow cytometric analysis of immunoglobulin and complement component c3 on the surface of trypanosoma lewisi. | we have reinvestigated whether surface immunoglobulin (sig) on trypanosoma lewisi is antibody directed toward parasite antigen by using flow cytometry to analyze parasites stained with fluoresceinated f(ab')2 fragments of antibodies to rat igg and igm. we have confirmed that igg antibody to the parasites is present both in the serum of rats and on the surface of parasites between the fourth and twentieth days of infection, that the amount of sig per cell increases as the infection progresses, an ... | 1986 | 3525820 |
| comparative histochemical studies of rats infected with a pathogenic and nonpathogenic trypanosome. | histochemical variations in tissues from rats inoculated with trypanosoma lewisi and trypanosoma rhodesiense were investigated. during peak parasitemia, the liver of rats inoculated with t lewisi showed increased glycogen distribution. however, glycogen depletion was noted in the liver and spleen of animals inoculated with living cells of t rhodesiense. depletion was very apparent from day 4 to day 10. throughout the period of observation, only a small amount of lipid infiltration occurred in ti ... | 1991 | 1875425 |
| a putative flagellar ca2(+)-binding protein of the flagellum of trypanosomatid protozoan parasites. | | 1990 | 2198539 |
| a medium for the continuous cultivation of bloodstream forms of trypanosoma lewisi at 37 c. | trypanosoma lewisi has been maintained continuously at 37 c for more than 2 yr in iscove's modified dulbecco's medium with 10% fetal calf serum and a feeder layer of rat fibroblasts. in this medium the continuously reproducing hematozoic culture forms resemble bloodstream forms of t. lewisi in that they appear morphologically similar in giemsa-stained preparations examined by light microscopy and have a surface coat that is absent in culture forms grown at ambient temperatures, when examined by ... | 1990 | 2213414 |
| metabolic activity of trypanosoma lewisi cultured in vitro in the presence of normal or ablastinic rat serum. | trypanosoma lewisi, in cultures supplemented with normal rat serum, synthesized the majority of new rna during the first 13 hr of the culture, whereas dna synthesis occurred from the 8th hr onwards and amino acids were incorporated into macromolecules uniformly throughout the 24 hr culture period. thymidine was taken up by the parasite only between the 7th and 14th hr of culture, unlike uracil and amino acids which were taken up as required. ablastin, a trypanostatic factor in the serum of infec ... | 1985 | 2581735 |
| interaction of nutrition and infection: effect of vitamin b12 deficiency on resistance to trypanosoma lewisi. | a metabolic imbalance technique was employed to study vitamin b(12) deficiency in rats infected with trypanosoma lewisi. throughout the observational period, animals on the deficient diet had lowered serum vitamin b(12) levels compared with complete and pair-fed animals. the decline in the level of the vitamin, ten days after the initiation of the experiment, continued progressively until the termination of the study. body weight gains and food consumption in rats on complete, vitamin b(12)-defi ... | 1985 | 3889354 |
| infectivity and route of penetration in rats after oral and intraperitoneal inoculations of bloodstream and in vitro-cultured metacyclic forms of trypanosoma lewisi. | morphological changes of trypanosoma lewisi blood trypomastigotes cultured in schneider's drosophila medium (sdm), supplemented or not with uric acid (sdm + ua), were compared to those that occurred in a control medium (m-199). no difference in trypanosome morphology and numbers was observed between sdm + ua and sdm cultures; there was little transformation into metacyclic stages in m-199. no difference was observed between the capacity of sdm- or sdm + ua-cultured metacyclic stages to infect ra ... | 1989 | 2693677 |
| murine natural resistance to trypanosoma lewisi involves complement component c3 and radiation-resistant, silica dust-sensitive effector cells. | the phenomenon of natural (innate) resistance is exemplified by the solid resistance of mice to infection with the rat-specific trypanosoma lewisi. we provide more information about the mechanism of resistance in this model system. resistance was not diminished in aged mice or reduced by ionizing radiation or splenectomy. there was no difference in resistance of c5-deficient mice (b10.d2/osn and akr) compared with their normocomplementemic counterparts (b10.d2/nsn and c57bl/6). treatment of mice ... | 1985 | 2981195 |
| trypanolytic activity, agglutinins, and opsonins in sera from animals refractory to trypanosoma lewisi. | an examination of sera from a range of animals refractory to trypanosoma lewisi showed that some contain trypanolytic activity and agglutinins for this trypanosome. trypanolytic activity was demonstrated in bovine, sheep, and rabbit serum. these sera were shown to also contain agglutinins. the trypanolytic activity in all three sera was abolished by heat inactivation at 56 degrees c for 30 min. studies with bovine serum showed that the lytic activity was totally inhibited by the addition of edta ... | 1985 | 3926649 |
| cooperative action of complement component c3 and phagocytic effector cells in innate murine resistance to trypanosoma lewisi. | mice display strong natural resistance to the rat-specific trypanosoma lewisi. intravenously injected intact t. lewisi parasites were eliminated by mice within 18 to 24 h. in comparison, "nude" t. lewisi organisms lacking the surface coat were rapidly and totally cleared from the bloodstream within 2 h postinoculation. similarly, in vitro-cultivated trypanosomes were readily eliminated by mice with the conspicuous absence of a lag phase. elimination of nude t. lewisi, like that of intact trypano ... | 1987 | 3026965 |
| serologic characterization of the somatic antigens of forms of trypanosoma lewisi from the bloodstream and cultures. | | 1971 | 4107191 |
| the effect of some amino acids on carbohydrate uptake by trypanosoma lewisi. | | 1974 | 4156217 |
| a comparative study of d-lactate, l-lactate and glycerol formation by four species of leishmania and by trypanosoma lewisi and trypanosoma brucei gambiense. | leishmania braziliensis panamensis, l. donovani, l. major, and l. mexicana amazonensis promastigotes, trypanosoma lewisi bloodstream forms, and t. brucei gambiense procyclic forms were incubated with glucose as sole carbon source. all species consumed glucose more rapidly under aerobic than anaerobic conditions. all produced glycerol under anaerobic conditions, though the rate of glycerol production by t. lewisi was markedly lower than that by the other species. the four leishmania species produ ... | 1988 | 3054535 |
| chromatographic separation of a rat serum growth factor required by trypanosoma lewisi. | | 1969 | 4180860 |
| influence of methods of preparation on the infectivity, agglutination, activity, and ultrastructure of bloodstream trypanosomes. | | 1974 | 4206929 |
| lack of protection against trypanosoma cruzi by multiple doses of t. lewisi culture forms. a discussion on some strains of "lewisi". | | 1974 | 4207915 |
| interaction of nutrition and infection: trypanosoma lewisi, folic acid levels in sera and tissues of normal and folic acid-deficient rats. | | 1974 | 4215256 |
| respiratory activity of trypanosoma lewisi during several phases of infection in the rat. | | 1968 | 4236168 |
| trypanosoma lewisi: creatine phosphokinase, ornithine carbamyl transferase, atpases, pi, and glucose levels in the rat host. | | 1968 | 4236169 |
| bent helical structure in trypanosoma lewisi minicircles. | by gel retardation assay and computational analysis we demonstrated a bent region in trypanosoma lewisi, localized in two different classes of minicircles. we showed that in each minicircle this bent region is unique, adjacent to one of two highly conserved regions and characterized by adenine stretches. the same properties are conserved in the majority of minicircles from trypanosomes tested so far. therefore, we suggest that the genetic information could be located in a definite structure of m ... | 1988 | 3066494 |
| the effects of adrenalectomy and splenectomy on trypanosoma lewisi infection in white rats. | | 1966 | 4288989 |
| the lipid metabolism of blood and culture forms of trypanosoma lewisi and trypanosoma rhodesiense. | | 1971 | 4330390 |
| mechanisms of amino acid transport in trypanosoma lewisi. | | 1972 | 4402092 |
| trypanosome sterols and their metabolic origins. | | 1972 | 4552279 |
| trypanosoma lewisi: in vitro growth in mammalian cell culture media. | | 1972 | 4552681 |
| trypanosoma lewisi: duration of immune state in rats. | | 1972 | 4557723 |
| trypanosoma lewisi: influence of sera and peritoneal exudate cells. | | 1972 | 4558416 |
| some aspects of aminotransferases of trypanosomes. | | 1972 | 4558830 |