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a comparison of sampling techniques for domestic populations of triatominae.six methods of sampling domestic populations of triatoma infestans (klug in brazil have been studied. the results suggest that where bug densities are low, the gomez-nuñez box may be used, but with higher bug densities withdrawal or removal collecting allows a direct estimation of the size of the bug population. the number of samples to be taken in removal collections depends upon the density of the bug population and the degree of accuracy required.1978364782
computer assessment of chromatin patterns on some germ line cells of the hemipteran, triatoma infestans klug.the digitized nuclear images of some feulgen-stained primary and secondary spermatocytes of triatoma infestans were analyzed with computer programs. different cell types could be mathematically discriminated in terms of distance of the condensed chromatin areas from the center of the nucleus, relative circumference of these areas, and staining intensity ratio of the condensed chromatin areas with respect to the whole nucleus. the method appears promising for further comparative studies involving ...1978104529
[biochemistry of the developmental cycle of triatoma infestans (vinchuca). 2. biosynthesis of fatty acids].the biosynthesis of fatty acids in triatoma infestans was studied in all the nymph stages and adult insects by feeding experiments with 1-14c acetate. in other experiments labeled acetate, 1-14c palmitate or 1-14c stearate were injected in the abdomen. in another group of experiments the abdominal non intestinal tissue of adult insects was homogenized and the supernatants of 10 000 x g and 105 000 x g were incubated with 1-14c acetyl-coa. the incorporation of the labeling in the fatty acids was ...1979400672
patterns of lability towards acid hydrolysis in heterochromatins and euchromatins of triatoma infestans klug. 1979383296
electron microscopic studies on blastocrithidia triatomae cerisola et al. 1971 (trypanosomatidae).in the bug triatoma infestans developmental stages of blastocrithidia tritomae, which can be mistaken for t. cruzi during xenodiagnosis, were studied by means of electron microscopy. it turned out that three different forms appeared during the progressive divisions: "micro-", "pro-" and epimastigotes. the morphological study revealed significant criteria for a distinction from t. cruzi stages. furthermore cyst-like bodies were observed often attached to the flagella of the different stages. as r ...1979396699
growth and differentiation of trypanosoma cruzi cultivated with a triatoma infestans embryo cell line.trypanosoma cruzi strain peru was cultivated in the presence of an established cell line of triatoma infestans embryo cells (ti- 32). bloodstream trypomastigotes differentiated into amastigote-like cells (first differentiation phase) which multiplied to form large clusters of cells. because of their clustering nature, a new term, "staphylomastigotes," has been proposed for this stage. after 10 days of cultivation, 90% of the staphylomastigotes underwent differentiation (2nd differentiation phase ...197943891
improvements in routine xenodiagnosis with first instar dipetalogaster maximus (uhler 1894) (triatominae).first instar dipetalogaster maximus proved as effective as third instar triatoma infestans in detecting circulating trypanosoma cruzi in patients with chronic infections examined in a routine xenodiagnostic laboratory. since rearing costs are diminished, d. maximus has now replaced t. infestans as the xenodiagnostic agent in our laboratory. however, further work is needed to define the optimal conditions necessary when using this species in xenodiagnosis.1979111570
studies of the domestic ecology of triatoma infestans by means of house demolition. 1979112663
dipetalogaster maximus (hemiptera, triatominae) for xenodiagnosis of patients with serologically detectable trypanosoma cruzi infection.in patients serologically positive for trypanosoma cruzi infection the three bug species/instar combinations used in xenodiagnosis showed third-instar dipetalogaster maximus to be more efficient in detecting circulating trypanosomes than the first instar of the same species which, in turn, is more sensitive than third-instar triatoma infestans. the sensitivity of the pool technique of faecal examination compared with individual dissection was investigated. four pool examinations (the product of ...1979119338
an outbreak of acute chagas's disease in the são francisco valley region of bahia, brazil: triatomine vectors and animal reservoirs of trypanosoma cruzi.following reports of an unusually high incidence of acute chagas's disease and the appearance of large numbers of triatoma infestans in the southwestern region of the state of bahia, triatomine bugs (hemiptera: reduviidae) and domestic animals in one of the affected communities were surveyed and examined for infection with trypanosoma cruzi. triatoma infestans was prevalent in houses and was also found in peridomestic habitats. t. sordida and t. pseudomaculata occupied peridomestic and sylvatic ...1979120045
[studies on the persistence of the infectivity of trypanosoma cruzi. ii. persistence of infectivity of t. cruzi in dead bugs (author's transl)].investigations into the viability time of t. cruzi in dead bugs experimentally infected with "peru" strain showed a maximum of 9 days for dipetalogaster maximus and 8 for triatoma infestans maintained at ambient temperature (26 degrees c). on refrigeration survival was increased to 60 days. in routine xenodiagnosis in the refrigerator 90 day survival was noted of both t. cruzi and the vector bug.1979396604
an insect acetylcholinesterase inhibitor from compound eyes of triatoma infestans (hemiptera).the presence of an acetylcholinesterase inhibitor in the compound eyes of adult triatoma infestans was demonstrated. the inhibitory activity was localized in the ocular pigments separated by disc gel electrophoresis. the inhibitor was selective against insect acetylcholinesterase, reversible, noncompetitive and heart stable.1979520485
susceptibility of triatoma infestans from two laboratory colonies to infection with trypanosoma cruzi. 19806777914
detection of host proteins in the intestine of triatoma infestans by agar double diffusion tests. 19806781039
[extra-intestinal phase of the life cycle of trypanosoma cruzi in triatoma infestans]. 19807010466
density regulation of domestic populations of triatoma infestans in brazil.twenty old houses in a rural area of central brazil were sampled monthly for triatoma infestans during 16 months. the samples indicated peak adult emergence between january and may, preceded by peak emergence of stage v, iv and iii nymphs respectively. stage i and ii nymphs were rarely taken in the samples. a much smaller peak of adult emergence occurred in september; thus the two peaks of adult emergence during the year were consistent with the approximately six months duration of egg-to-adult ...19807010697
nutritional status of domestic populations of triatoma infestans. 19807010698
[detection of host proteins in the intestine of triatoma infestans 3 months after ingestion]. 19807005599
[preliminary results concerning the ecology of triatoma infestans (klug) and congeneric species, with special reference to peri-domiciliary populations]. 19807005602
[triatoma infestans: effect of artificial feeding on its life cycle]. 19807005604
[presence of oöphagous parasitoids of triatoma infestans in cruz del eje department, córdoba]. 19807005605
[feeding of triatoma infestans in the laboratory]. 19806758065
[proposal for a predator for the destruction of triatoma infestans: tarentola mauritanica.]the task of chagas disease control is overwhelming. one of the measures is the destruction of the bugs which act as vectors. in this paper the authors suggest trying this with a predator, a voracious insectivorous lizard, a kind of gecko: the tarentola mauritanica or moorish gecko. these geckos were transported fortuitously to argentina in cargoes of cork from their natural habitat, the mediterranean basin. they have adapted easily to their new environment. their ability to eat the kissing bug ( ...198022167700
toluidine blue binding capacity of heterochromatin and euchromatin of triatoma infestans klug.the localization of the absorption peaks of toluidine blue-stained heterochromatin (ho and hs) and euchromatin (eo and es) of the malpighian tubules of the blood-sucking hemipteran, triatoma infestans klug was studied cytophotometrically (ho and eo: hetero- and euchromatin of nuclei with one single chromocenter; hs and es: hetero- and euchromatin of nuclei with several chromocenters). shifts of the absorption peaks to longer wave-lengths were found for the euchromatin fractions and hs after rnas ...19806161909
neurogenesis and occurrence of cholinesterase in eggs of triatoma infestans. 19806102016
[effects of the addition of anticoagulants in the artificial feeding of triatoma infestans]. 19807005613
[biochemistry of the cyclic evolution of triatoma infestans (vinchuca). iv. de novo biosynthesis of lipids in fat body and testicles].the de novo biosynthesis of lipids by isolated fat bodies and testicles of triatoma infestans was demonstrated by incubation with 1 14c sodium acetate. the fat body synthetized preferentially triacylglycerols but the label was also found in phospholipids. when hemolymph was added to the medium the label found in diacylglycerols was largely increased. in the testicles the label was preferentially incorporated to the phospholipids and little was found in diacylglycerols and triacylglycerols.19806765592
[biochemistry of the cyclic evolution of triatoma infestans (vinchuca). iii. dynamics of the incorporation of fatty acids in lipids].more than 80% of total lipids of triatoma infestans are triacylglycerols and only 3.7% and 4.0% are phosphatidyl-ethanolamine and phosphatidylcholine, whereas the diacylglycerols are 0.2%. however in hemolymph that contains 6.8 mg of lipids per ml predominate the phospholipids and there are approximately 22% of diacylglycerols with very little triacylglycerols. therefore these diacylglycerols may play an important function in fatty acid transport since they incorporate in a few minutes injected ...19806765591
detection of viral particles in the salivary glands of the hemipteran, triatoma infestans klug. 19817326701
[biochemistry of the evolutive cycle of triatoma infestans (vinchuca). v. volatile fatty acids emission].the composition of the volatile fatty acids emitted by triatoma infestans of both sexes was studied. they were constituted by a mixture of the acids acetic, propionic, butyric, isobutyric, isovaleric, valeric and traces of isohexanoic and octanoic. acetic acid was predominant followed by isobutyric and then by propionic acid. the other fatty acids are minor constituents. when acetic acid was discounted, the remaining composition was similar to the volatile fatty acid distribution pattern of brin ...19816765007
skin reactions to bug bites as a result of xenodiagnosis.cutaneous allergic reactions to bites of two bug species triatoma infestans and dipetalogaster maxima, were studied in an area where t. infestans is the local domestic vector. while more delayed skin reactions occurred with the indigenous vector, reactions also occurred with d. maxima. repeated exposure to d. maxima produced more intense immediate skin reactions. first-stage d. maxima bugs produced a lower frequency and intensity of skin reaction. it is concluded that further work on this proble ...19816798721
influence of organ extracts of triatoma infestans on differentiation of trypanosoma cruzi.the influence that extracts of different t. infestans organs possess to induce trypanosoma cruzi differentiation from epimastigotes to metacyclic forms in grace's and modified grace's media was analyzed. growth of epimastigotes was adequate in grace's medium when homogenates of stomach, testes, and ovaries from recently fed insects were added. growth of epimastigotes was adequate when testes or ovaries obtained from recently fed triatomes were added to modified grace's medium. similar results we ...19817014817
comparison of techniques for detection of domestic infestations with triatoma infestans in brazil.the detection of infestations of triatominae in houses in regions endemic for chagas's disease is a criterion frequently used in the selection of areas, or of individual houses, for treatment in insecticide campaigns as well as in the evaluation of insecticide performance. several different methods for detecting domestic infestations with triatominae were compared: night capture, capture of five bugs with the aid of a flushing-out agent and use of card boxes of the gómez-núñez type. the flushing ...19817036429
trypanosoma cruzi: comparative studies of infectivity of parasites ingested by triatoma infestans and those present in their feces.artificial feeding of the insects with whole blood containing trypomastigotes resulted in triatome infection; the parasites were present in the host feces after 15--30 days and, when inoculated into mice, elicited parasitemia in 100% of the cases and deaths in 20--70%. this mortality indicates a reduction of the original infective capacity of the bloodstream form, which kills 100% of the mice even when inoculated with a single trypomastigote. when triatomes were fed whole normal mouse blood cont ...19816115550
field experiments of dispersive flight by triatoma infestans.using marked male triatoma infestans allowed to escape and fly on a little-used airport in brazil and salt flats in argentina, 33 of 169 flew in the former and 28 of 528 in the latter experiment. many of the bugs which flew had been classed as poorly fed. the proportion of bugs which flew was in reasonable agreement with predictions based on laboratory observations. it was shown that in the field male bugs are capable of flights in excess of 100 m. the method described served the purpose of this ...19817034312
[triatoma infestans as a vector of hepatitis b virus].mosquitoes and bed bugs may play a role in the transmission of hepatitis b virus (h.b.v.). we investigated this possibility with the triatoma infestans, which is a hematophagous insect widely prevalent in the argentine republic. triatoma infestans fed with serum or blood contaminated with h.b.v. were studied at 7, 14, and 21 days after contamination. stool and insect homogenates were positive for hbsag at each time checked. considering the domestic habits and hematophagous condition of triatoma ...19817034439
field trial of permethrin for the control of triatoma infestans. 19817034831
the activity of nifluridide on reduviids and rodent and human trypanosomes.the ability of nifluridide to kill reduviids was assayed in mice fed 7 ppm in diet and on cattle injected subcutaneously at 5 mg/kg body weight. nifluridide was systemically active against triatoma infestans on mice and rhodnius prolixus on cattle. no effects on trypanosoma (schizotrypanum) cruzi could be detected in the intestinal contents of triatoma infestans killed by the compound. in vitro and in vivo studies were conducted to determine the effects of nifluridide on trypanosomes growing in ...19826815915
trypanosoma cruzi: biological characterization of 19 clones derived from two chronic chagasic patients. i. growth kinetics in liquid medium.nineteen clones of trypanosoma cruzi were obtained as single-cell isolates from triatoma infestans. ten of the clones were isolates from a patient with chronic chagas' disease; nine clones were isolates from a dog infected with t. cruzi strain ca-i isolated originally from a chronic chagasic patient. the growth kinetics and peak modal coulter volume of these clones were characterized. significant inter- and intra-group differences between growth rates and peak modal volumes were found. these dat ...19826816924
feeding patterns of triatoma infestans (hemiptera: reduviidae) in relation to transmission of american trypanosomiasis in argentina. 19826818346
artificial feeding of triatoma infestans (hemiptera: reduviidae) with defibrinated blood. 19826750124
inhibition of xenograft rejection reaction in the bug triatoma infestans during infection with a protozoan, trypanosoma cruzi. 19826754821
[feeding preferences in 3 species of triatominae (hemiptera: reduviidae) in experimental conditions].feeding preferences of three species of triatomines (triatoma infestans, t. dimidiata, and rhodnius prolixus) on four vertebrate hosts (opposum, dog, chicken and toad) were studied in a specially designed cage during daylight (2 hours) and at night (14 hours). t. infestans and r. prolixus remained close to the host after feeding, while t. dimidiata wandered a short distance away, apparently for protection against preying by the host. r. prolixus showed the lightest values of ingestion in relatio ...19826763728
[domestic ecology of triatoma infestans in mambaí, goiás-brazil]. 19826763760
ecdysteroids: biochemical mechanism of 20-hydroxyecdysone inactivation in triatoma infestans (hemiptera, reduviidae).when 3h-20-hydroxyecdysone was injected into triatoma infestans during the fifth nymphal instar, it was converted to very polar metabolites (peak 1). the polar metabolites were glucuronoconjugates of 20-hydroxyecdysone. acetylation of the conjugates followed by hydrolysis with glucuronidase gave a major labelled product: 20-hydroxyecdysone and minor peaks corresponding to a mixture of 20-hydroxyecdysone acetates. these results indicated that the 2,3,22,25-glucuronoconjugates of 20-hydroxyecdyson ...19826764707
the effect of wall plaster on a domestic population of triatoma infestans. 19826819871
the ecology of chagas disease in chile.chagas disease probably affects over half a million people in chile, principally in rural communities in the fertile valleys of the arid 'norte chico' region, north of santiago. the main domestic vector is triatoma infestans, but triatoma spinolai, although mainly in rocky sylvatic and peridomestic ecotopes, also invades houses. since the spanish invasion in the sixteenth century, and particularly during the last 100 years, the endemic region has suffered an ecological breakdown, largely due to ...19826821391
[biochemistry of the developmental cycle of triatoma infestans (vinchuca). vi. identification and lipid composition of hemolymph lipoproteins of adult males].three lipoproteins were separated from the haemolymph of adult males of triatoma infestans fed on hen blood. the densities were similar to the high density lipoprotein (hdl) and to two very high density lipoproteins (vhdl) isolated from a pool of adult male and female insects fasted during twelve days. the relative distribution and composition of the three lipoproteins were studied. the fatty acids were mainly carried by the 1.3 and 1.2 diacylglycerols of high density lipoprotein. triacylglycero ...19826760669
isolation and characterization of the haemolymph lipoproteins of triatoma infestans.1. three lipoproteins differing in hydrated densities were isolated by ultracentrifugal procedures from the haemolymph of adult and fasted triatoma infestans. 2. they are the high density lipoprotein hdl (d = 1.115-1.152) and the two very high density lipoproteins vhdl-i (d = 1.190-1.231) and vhdl-ii (d = 1.245-1.260). hdl was the predominant lipoprotein. 3. the total lipid content expressed as % of lipoprotein weight in hdl, vhdl-i an vhdl-ii was 30.1, 7.8 ad 2.9% respectively. diacylglycerols ...19827049559
cytoplasmic inclusions in virus-infected salivary gland cells of triatoma infestans klug. 19836369441
[ecological aspects of south american trypanosomiasis. xviii - development and annual cycles of triatoma infestans, t. sordida and rhodnius neglectus colonies in artificial ecotopes and in peri- and extra-domicilliary environments]. 19836419343
factors controlling the volume of feces produced by triatomine vectors of chagas' disease.triatomine species influenced volume of feces produced; triatoma dimidiata produced the largest volume of feces followed by panstrongylus megistus, rhodnius prolixus, and triatoma infestans. moreover, stage and sex affected fecal production; 5th-stage female nymphs excreted the largest volume of feces. the amount of blood ingested was significantly correlated with the volume of feces produced in 10 out of 11 experimental groups. triatome size and volume of feces produced were less closely correl ...19836142633
[effect of the hemolymph of triatoma infestans on the morphogenesis of trypanosoma cruzi].growth and differentiation patterns induced by t. infestans whole hemolymph as well as by hemocyte free or hemocyte and quinone free samples were similar; these results indicate that neither hemocytes nor quinones interfered in the duplication of epimastigotes or in their differentiation to metacyclic forms. the minimum amount required to induce differentiation was 2%, lacking inhibitory effect even when assayed at a concentration of 30%. differentiation was reached simultaneously with the expon ...19836400767
the characterization of chilean and bolivian trypanosoma cruzi stocks from triatoma infestans by isoelectrofocusing.culture forms of 12 chilean and 9 bolivian trypanosoma cruzi stocks were compared isoenzymatically by the following enzymes: non-specific esterase, phosphoglucomutase, glucose-6-phosphate dehydrogenase, glucosephosphate isomerase, and alcohol dehydrogenase. on the basis of the electrophoretic mobility of these enzymes the stocks were classified into two main groups. ten chilean stocks were characterized as group ii; two stocks showed enzyme patterns of group i. in contrast, five bolivian stocks ...19836349161
the microdistribution of isoenzymic strains of trypanosoma cruzi in southern bolivia; new isoenzyme profiles and further arguments against mendelian sexuality.132 trypanosoma cruzi stocks were collected in southern bolivia (99 stocks in tupiza, 33 in tarija), and were characterized using five enzymes (six loci). from these 132 stocks, a sample of 21 was studied using 10 enzymes (12 loci) to establish the genetic distances between them. only five different isoenzymic strains were registered among the 132 stocks: the taxonomic status of these strains is discussed. the distribution of the strains indicated that a founder effect was not a constant fact at ...19846237474
isozyme heterogeneity and numerical taxonomy of trypanosoma cruzi stocks from chile.fifty-three stocks of trypanosoma cruzi were isolated in chile, 13 from patients, 32 from the domestic triatomine vector triatoma infestans, and 8 from the silvatic and peridomestic vector t. spinolai. the majority of isolates from triatomine bugs were made by the direct culture of infected faeces. the 53 stocks and a single clone were characterized by a combination of starch-gel and cellulose acetate enzyme electrophoresis. three groups of t. cruzi stocks were apparent from either simple visual ...19846237475
scanning electron microscopic studies of trypanosoma cruzi in the rectum of its vector triatoma infestans.the cuticular surface of the rectum of triatoma infestans and its colonization by a trypanosoma cruzi strain originating from the same locality as the bugs were studied by scanning electron microscopy at different weeks post infectionem. on the basis of the cuticular folding, the rectum can be subdivided into five regions. the rectal gland has the finest structure and the region anterior to the anus the deepest folds. try. cruzi always prefers to colonize the rectal gland, while the other region ...19846382848
identification of trypanosomes isolated from reduviidae from north chile.examination of 54 triatoma infestans from a village near the european southern observatory la silla in chile and of 9 triatoma spinolai from the territory of the observatory showed that 10 t. infestans were infected with trypanosomatids. mice were infected with in vitro cultures initiated with five different trypanosomatid isolates and treated with the immunosuppressive drug cyclophosphamide to increase the parasitemia of the flagellates. evidence of the presence of t. cruzi was provided by a co ...19846421021
the development of extra-intestinal cycle of trypanosoma cruzi in triatoma infestans and panstrongylus megistus.by applying various histological techniques the results obtained were similar to those in lacombe's previous publications referring to the development of trypanosoma cruzi in haemolymph, the later penetration in the malpighian tubes and their return to the digestive tract. trypomastigotes and sphaeromastigotes are found in the promesenteron after two hours of feeding the insect with mice blood containing numerous trypanosoma cruzi. some parasites move to the promesenteron from postmesenteron and ...19846385793
circadian rhythms of locomotor activity in triatoma infestans (hemiptera: reduviidae). 19846374148
trypanosoma cruzi from the paraguayan chaco: isoenzyme profiles of strains isolated at makthlawaiya.at makthlawaiya, in the paraguayan chaco, the prevalence of trypanosoma (schizotrypanum) cruzi infection among both domestic triatoma infestans and domestic dogs was 38%, and igg anti-t. cruzi antibody was detected by the quantitative enzyme-linked immunosorbent assay (elisa) in 80% (105/133) of human sera. ninety percent (25/28) of t. cruzi strains isolated from both t. infestans and dogs showed heterozygous isoenzyme profiles for glucose phosphate isomerase, phosphoglucomutase and 6-phosphoglu ...19846239030
integumental esteratic activity in triatoma infestans and its contribution to the degradation of organophosphorus insecticides.esteratic activity was found in the integument of adult triatoma infestans, principally located in the epidermis. specific activity was on average 29.3 nm phenylthioacetate/hr per anatomical unit. esteratic activity depends on the insect's age and its starvation state. a dramatic increase was observed 1 week after moulting followed by a slight decay as a function of the age. a significant decrease of the activity was observed with a longer fasting time. integumental esterases were characterized ...19846149865
[biochemistry of the developmental cycle of triatoma infestans. vii. lipid composition of the cuticle surface extracted with hexane].the lipid composition of triatoma infestans (vinchuca) epicuticle was studied. the insect lipids were extracted with hexane and fractionated by chromatography. long chain fatty alcohols, hydrocarbons, waxes, triacylglycerols, diacylglycerols, free fatty acids, cholesterol, cholesterol esters and monoacylglycerols were detected. the composition of fatty acids, hydrocarbons and alcohols was studied by gas-liquid chromatography and mass spectrography. linear and branched hydrocarbons were separated ...19852938407
[biochemistry of the growth cycle of triatoma infestans (vinchuca). viii. preliminary study of hemo-lymphatic apolipoproteins in the adult male].the three lipoproteins of high (hdl) and very high density (vhdl-i and vhdl-ii) were separated from the hemolymph of adult males of t. infestans. they were delipidated and the corresponding apolipoproteins examined by sodium dodecyl sulphate (sds) gel electrophoresis in polyacrylamide in the presence of 2-mercaptoethanol. they were also iso-electro focused in a ph gradient of 5 to 8. all three groups of apolipoproteins were separated in several polypeptide chains, but all of them had in common a ...19852938415
[study of 11 enzymes and formal genetic findings for 19 enzymatic loci in triatoma infestans (hemiptera: reduviidae)]. 19853907524
population dynamics and control of triatoma infestans. 19853931580
[isoenzymatic studies of the principal vector of chagas disease: triatoma infestans (hemiptera: reduviidae)]. 19853931581
[fenitrothion (oms-43) in the control of triatoma infestans, the vector of chagas disease in argentina]. 19853931583
chagas' disease in pre-columbian south america.the quest for the origin and dispersion of chagas' disease, the second most important vector-borne disease in latin america, has epidemiological, immunological, and genetical implications. conjectures based on accounts of chroniclers, reviews of the archaeological literature and the present distribution of triatomine bugs, the vectors of the disease, held that the origin of the adaptation of triatoma infestans (a species of the subfamily triatominae) to human dwellings occurred in prehistoric ti ...19853936363
theoretical approach to active dispersal and colonization of houses by triatoma infestans.dispersive flight by triatoma infestans was modelled by assuming either unidirectional flight in a straight line, or that flight followed a pattern of 'random walk' analogous to two-dimensional brownian motion. parameter estimates for the models were derived from previous fieldwork in argentina and brazil. calculated probabilities of houses becoming infested over a 1 year period were compared with actual changes of house infestation in a small farming community in central brazil. it was found th ...19853906147
effect of vector on infectivity of trypanosoma cruzi.a comparative study was carried out on the interaction between triatoma infestans and bloodstream forms (bsf) of trypanosoma cruzi isolates ra and up, both lethal for mouse, and ca-i nonlethal for this host. parasite duplication was readily detected in triatomes fed with ca-i, metacyclic (mtc) differentiation reaching a maximum at an optimum ingestion level of 250 bsf/insect. progress and differentiation proved much lower for ra, but reached intermediate values for the up isolate. assays for inf ...19852862777
colonization of the rectum of triatoma infestans by trypanosoma cruzi: influence of starvation studied by scanning electron microscopy.the colonization of the different regions of the rectum of triatoma infestans by a trypanosoma cruzi strain (zymodeme i) originating from the same locality as the bugs was studied by scanning electron microscopy after different periods of starvation of the bugs. throughout the first 16 weeks no changes in colonization pattern could be observed. parasite density was always minimal at the midgut/rectal junction and highest on the rectal pads; it was at a similar level in the other three regions of ...19862882662
trypanosoma cruzi: differentiation after interaction of epimastigotes and triatoma infestans intestinal homogenate.incubation of trypanosoma cruzi epimastigotes with triatoma infestans intestinal homogenate leads to differentiation to the metacyclic trypomastigote. features of this interaction are presented. the morphogenetic mechanism was triggered almost at once; for the minimum interaction period assayed (15 min), the degree of differentiation achieved in grace medium by day 6 was 70.0 +/- 9.0%. longer interaction periods failed to improve differentiation. the morphogenesis became irreversible at 4 hr aft ...19863023131
trypanosoma cruzi and trypanosoma rangeli in saimiri sciureus from bolivia and saguinus mistax from brazil.examination of blood films for trypanosomes in primates housed at the tulane university delta regional primate research center showed that 47% (32/68) of the bolivian saimiri sciureus and 51% (68/135) of brazilian saguinus mistax harbored one or more types: trypanosoma (schizotrypanum) cruzi in 6% to 7% and trypanosoma (herpetosoma) spp. or trypanosoma (megatrypanum) spp. in 39% and 45%, respectively. trypanosomes were isolated from a sample of the infected monkeys and morphobiological studies w ...19863082228
investigation of hycanthone binding to dna in chromatin with different supra-organization, composition, and function.hycanthone is a drug used for the clinical treatment of schistosomiasis, although inducing chromosomes breaks and mutagenesis when it enters the dna double helix. based on visual observation of characteristics of basophilia and anisotropy after toluidine blue staining, a preferential binding of hycanthone to heterochromatin could be demonstrated for the nuclei of the malpighian tubules of triatoma infestans. in other cellular systems like cattle kidney cells in culture, plant cells, and mouse ly ...19863090842
an outbreak of chagas' disease in southwestern bahia, brazil.an outbreak of 20 cases of acute chagas' disease followed the movement of triatoma infestans into the county of riacho de santana, bahia, brazil. the outbreak was unusual in that the majority of cases occurred in adults. vector control measures were implemented. three years after the outbreak, a rural community was examined to determine the extent of human infection and disease due to trypanosoma cruzi. ninety of 440 residents (20.5%) had serologic evidence of infection, but rates of electrocard ...19863094393
[biomorphogenetic changes caused by the application of precocene ii in nymphs of triatoma infestans (klug, 1834) (hemiptera, reduviidae, triatominae)].the morphogenetic effect of precocene ii on 4th instar nymphs of triatoma infestans was examined. topical treatment with precocene ii (200, 300 and 400 micrograms/nymph) induced the formation of adultoids with the following characteristics: rudimentary wings, three segmented tarsi, ocelli, deformed genitalia and mouth-parts and testes with intermediary development. precocene ii also increases the duration of the molting cycle. the survival of the adultoid insects was related to the inverse of th ...19863295468
[experimental infection of triatoma infestans (hemiptera: reduviidae) with leptospira icterohaemorrhagiae and its transmission to laboratory mammals]. 19863296076
an improved procedure for the purification of trypanosoma cruzi (chagas, 1909) metacyclics from the insect vector.we have developed an improved procedure for isolating and purifying the metacyclic trypomastigote form of trypanosoma cruzi from infected triatoma infestans. the procedure was simple, did not require time-consuming removal of the insect gut, and gave a good recovery of metacyclics. purification involved centrifugal flotation of the parasites in percoll followed by diethylaminoethyl cellulose column chromatography. the resulting purified metacyclics exhibited no loss of infectivity when assayed i ...19863514902
lability to acid hydrolysis in some different dna-protein complexes of spermatozoa.the feulgen hydrolysis kinetics was investigated in spermatozoa with different composition in dna-protein complexes. the species used were: bos taurus (arginine rich nuclear protein also containing cystine residues), pichroplus bergi, triatoma infestans (arginine-rich nuclear protein), lytechinus variegatus and apis mellifera (lysine-rich nuclear protein). the spermatozoa were subjected to feulgen's reaction, after varying the fixative type and the hydrolysis times. feulgen-dna values were obtai ...19863088898
trypanosoma cruzi morphogenesis: preliminary purification of an active fraction from hemolymph and intestinal homogenate of triatoma infestans. 19863528446
a comparative study of trypanosoma cruzi enzyme polymorphism in south america.1. the electrophoretic patterns of 13 loci were used to compare the three main t. cruzi zymodemes (z) circulating in north/northeastern brazil (br 1 through 3) with the four principal zymodemes present in southeastern (bra through d) brazil. 2. nei's standard genetic distances (d) obtained by paired comparison of the brazilian zymodemes indicate the presence of four divergent groups, separated by d = 1.18. zymodemes brb and brd presented heterozygous patterns for six and three loci, respectively ...19863307956
a permeability barrier in the testis of an insect triatoma: a freeze-fracture and lanthanum tracer study.in vertebrates, the testicular permeability barrier has been the subject of numerous studies. some recent observations also indicate the existence of such a barrier in some invertebrates, e.g. insects and worms. with the aim of determining whether the morphological features of the blood-testis barrier generally found in vertebrates can be extended to other animals, we studied the testis of the insect triatoma infestans using electron-dense tracers and freeze-fracture techniques. this organ is di ...198618620169
[biochemistry of the evolutive cycle of triatoma infestans. ix. composition of cuticular hydrocarbons compared to other triatominae].the hydrocarbon composition of epicuticular lipids of different species of triatomini were determined and compared by gas-liquid chromatography. t. infestans, t. delpontei, t. rubrovaria, t. sordida, t. guasayana and t. vitticeps from infestans subgroup and t. pallidipennis from rubrofasciata, were studied. all these species had in common the same kind of hydrocarbons. the major components were n c29; n c31; 12+14+15+18 methyl c38; 15, 19+14, 18 dimethyl c39; 12+14+17+19 methyl c36 and 4 methyl ...19862945401
vitellin and vitellogenin characterization of triatoma infestans and related species.the vitellogenin-vitellin (vg-vn) of triatoma infestans is a glycolipoprotein with a mol. wt. of 220,000; is a high density lipoprotein (1.18-1.21 g/ml) with low electrophoretic mobility at ph 8.2. there are many common proteins present in females, males, nymphs and eggs, but none is a glycolipoprotein. the major band of protein revealed a mol. wt. of 43,000, it is an anodic protein which appears in all the fractions of saline gradient. males and females have a glycolipoprotein with electrophore ...19863111174
recombination nodules, synaptonemal complexes and heterochromatin in the hemipteran triatoma infestans. 19873332298
the occurrence of arachidonic acid in triatoma infestans.1. gas-liquid chromatography and mass spectrometry were used to verify the presence of arachidonic acid (20:4 omega 6) in adult male and female organs of the blood-suckling bug triatoma infestans. fat body, gonad and head lipids were analyzed. 2. male gonads contained the highest percentage of phospholipids and the highest percentage of arachidonic acid. 3. phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine and sphingomyelin were isolated from gonads and head ...19873117486
activity of the insect growth regulator fenoxycarb (ro-13-5223) on triatoma infestans (hemiptera).1. fenoxycarb (ro-13-5223) exhibits a strong juvenile hormone type of activity against triatoma infestans. 2. topical treatment of last-stadium nymph with the juvenoid caused the formation of superlarvae, adult-larvae intermediates and adultoids. the ed50 was 0.02 microgram/insect. 3. taking into account abnormalities in oceli, head, thorax, legs, wings, abdomen, conexivo and external genitalia, a scoring system to evaluate the retention of juvenile characters after moulting was developed. 4. in ...19872888581
colonization of the rectum of triatoma infestans by trypanosoma cruzi studied by scanning electron microscopy: influence of blood uptake by the bug.the colonization of the different regions of the rectum of triatoma infestans by trypanosoma cruzi was studied in unfed larvae, during and after feeding of the bug by scanning electron microscopy. the rectal pads always possessed the highest population densities, but in some bugs the main rectal sac and the region around the anus were also covered by a "carpet" of flagellates. such high densities were never observed at the midgut/rectal junction. a slight decrease in this region might be caused ...19873309941
trypanosoma cruzi: differentiation to metacyclic trypomastigotes in the presence of adp-ribosyltransferase inhibitors.the participation of adp-ribosyltransferase in trypanosoma cruzi differentiation to the metacyclic stage was evaluated by analyzing morphogenesis blockage by specific enzyme inhibitors: benzamide, 3-aminobenzamide, theophylline, and nicotinamide. in vitro assays showed a statistically significant reduction in the number of metacyclic forms only when any one of the four inhibitors was added during the period of interaction between epimastigote and triatoma infestans intestinal homogenate or when ...19872960557
isozyme evidence of lack of speciation between wild and domestic triatoma infestans (heteroptera: reduviidae) in bolivia. 19873546693
small nonoccluded viruses from triatomine bug triatoma infestans (hemiptera: reduviidae). 19873549911
polyploidization of the btc-32 cell line from triatoma infestans (hemiptera, reduviidae).the cytophotometric evaluation of the feulgen-dna content of the btc-32 cells at passage 160 after 6 days of growth demonstrated that polyploidy is relatively frequent in this cell line. 4c values were assumed to pertain to diploid nuclei at the s or g2 phases but also to polyploid nuclei at the g1 phase. polyploidy in 4c nuclei is assumed to be attained by endomitosis. however, there are morphological indications that polyploidization in cells with an 8c-128c feulgen-dna content could result fr ...19873333490
[home ecology of trypanosomiasis americana: feeding profile of triatoma infestans in a rural area of the santiago del estero province, argentina]. 19873333976
trypanosoma cruzi isolates from argentina and chile grouped with the aid of dna probes.fifty-two isolates and several clones from trypanosoma cruzi, the agent of chagas' disease, were analyzed using cloned minicircles or total kinetoplast dna as probes. isolates were obtained from triatomines, guinea pigs and infected humans in the central and northern regions of argentina and the north of chile. 35% of all the randomly selected isolates could be identified with one cloned minicircle probe. this widely distributed t. cruzi group was detected on both sides of the andes mountain ran ...19872823134
epidemiology of chagas' disease in northern chile: isozyme profiles of trypanosoma cruzi from domestic and sylvatic transmission cycles and their association with cardiopathy.trypanosoma cruzi was isolated from 98 patients, 59 triatoma infestans, 51 triatoma spinolai, and 1 octodon degus from northern chile. with few exceptions, stocks originating from domestic hosts were classified, based on their isozyme profile, as principal zymodeme (z)2, while sylvatic stocks from t. spinolai and the rodent o. degus showed z1 profiles. these results indicate the existence of separate domestic and sylvatic transmission cycles. clinical data and t. cruzi isozyme profiles from 107 ...19873116867
differences in binding of lectin-gold conjugates by trypanosoma cruzi and blastocrithidia triatomae (trypanosomatidae) in the intestine of triatoma infestans (reduviidae).two species of trypanosomatid flagellates, trypanosoma cruzi and blastocrithidia triatomae which develop in the intestine of triatoma infestans, were incubated with lectin-gold conjugates to demonstrate sugar components of the cell surface with the electron microscope. t. cruzi, strain "chile 5" (zymodeme 1), bound sba-gold, revealing n-acetyl-galactosamine and/or galactose residues. wga-bsa-gold, specific for n-acetylglucosamine, did not bind to the surface of this flagellate. on the other hand ...19873125542
dynamics of transmission of trypanosoma cruzi in a rural area of argentina: ii. household infection patterns among children and dogs relative to the density of infected triatoma infestans. 19873126846
control of chagas disease in brazil.chagas disease (south american trypanosomiasis) is a chronic but often fatal disease endemic throughout much of latin america. serological surveys suggest around 24 million people seropositive for the causative agent, trypanosoma cruzi (fig. 1), with over 65 million living in the endemic areas and at risk to infection. in brazil, over 25 million people are considered at risk, and control of the disease constitutes one of brazil's public health priorities. treatment or vaccination against t. cruz ...198715462880
development of isolated and group-reared first instars of triatoma infestans infected with trypanosoma cruzi. 19883057492
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