| computer analysis of stained chromatin on malpighian tubes of triatoma infestans klug (hemiptera, reduviidae). | | 1978 | 370689 |
| [survival of the human immunodeficiency virus (hiv-1) in triatoma infestans (klug, 1834)]. | triatoma infestans is the main domestic vector of trypanosoma cruzi, the parasitic agent of chagas' disease in south america. we investigated whether triatoma infestans could shelter the hiv-1 virus. for this purpose, we measured the survival time of the virus in the alimentary tract. fifth-instar nymphs of the blood-sucking bug were fed through an ad hoc apparatus with venous blood from asymptomatic hiv-1 seropositive patients. we attempted to evidence the virus by cultivating material from the ... | 1992 | 1280179 |
| [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. | 1979 | 396604 |
| establishment and characterization of a cell line (btc-32) from the triatomine bug, triatoma infestans (klug) (hemiptera: reduviidae). | the establishment of a cell line from embryonic tissues of the triatomine bug, triatoma infestans is described. the cell line consists of three cell types which are described, and has a population doubling time of 48 hours during the logarithmic phase of growth. a proportion of the cells remain in the medium as floaters. of the chromosome preparations that could be counted, the majority contained the diploid (2n = 22) number. the cell line has undergone 129 subcultures and has been maintained fo ... | 1977 | 322623 |
| assembly pheromone of triatoma infestans and rhodnius prolixus nymphs (hemiptera: reduviidae). | | 1977 | 328883 |
| [cytochemical data on histones of the heterochromatins and euchromatins of triatoma infestans klug (author's transl)]. | in cells of the malpighian tubes of triatoma infestans klug, the histone content reactive to the alkaline fast green method does not remarkably differ when nuclei with various heterochromatic patterns (t1 and t8) are compared to each other. the fast green-histone values for the euchromatins (and heterochromatins) of both nucleus types also appear not differing. however, the possibility that these histones are differently linked to dna in euchromatin or heterochromatin variants is not to be ruled ... | 1977 | 339295 |
| effect of azadirachtin on the development of trypanosoma cruzi in different species of triatomine insect vectors: long-term and comparative studies. | studies were carried out on the effects of azadirachtin on the course of trypanosoma cruzi infection in the gut of different triatomine vector species. in rhodinus prolixus the development of t. cruzi clone dm28c decreased in a dose-dependent manner, and the ed50 of this inhibitory effect was 0.25 microgram azadirachtin/ml bloodmeal. using this insect, we conducted a long-term experiment which showed that azadirachtin (1.0 microgram/ml bloodmeal) completely blocks the development of t. cruzi eve ... | 1992 | 1401990 |
| [epidemiology of chagas disease in chile. housing conditions related to the presence of triatoma infestans and the rate of humans and animals infected by trypanosoma cruzi (author's transl)]. | | 1978 | 104721 |
| [new comparative studies between dipetalogaster maximus and triatoma infestans in the xenodiagnosis of chronic human chagas infection]. | | 1978 | 98820 |
| some cytochemical characteristics of the malphighian tube cells in the blood-sucking bug, triatoma infestans klug. | | 1977 | 610857 |
| determinants of the domiciliary density of triatoma infestans, vector of chagas disease. | in two heavily infested rural villages of santiago del estero, argentina, where no indoor-spraying with residual insecticides had ever been carried out by official control services, we studied the influence of roof and wall structure, domestic use of insecticide, family size and the number of domestic dogs, on the domiciliary density of triatoma infestans (klug). bug density was significantly associated with (1) the interaction between insecticide use and type of roof, (2) the structure of indoo ... | 1992 | 1600232 |
| [natural infection of calomys musculinus (rodentia, cricetidae) by trypanosoma cruzi]. | in the rural area of las higueras, río cuarto, córdoba, argentina, a trypanosoma was isolated from a wild rodent (c. musculinus). the trypanosome was classified as trypanosoma cruzi because of the following characteristics: morphology as described by hoare for the schizotrypanum sub-genus: thin shaped, pointed back end, nucleus placed approximately in the middle of the body, prominent and subterminal kinetoplast and short free flagellum. the size measurements were as follows: total lengh 22.02 + ... | 1977 | 408884 |
| 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 ... | 1979 | 120045 |
| 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 ... | 1979 | 119338 |
| degradation of serum proteins in triatoma infestans. | | 1976 | 59671 |
| [laboratory study on the immediate and persistent insecticide activity of the pyrethroid lambda-cyhalothrin on nymphs of iv instar triatoma infestans]. | lambda-cyhalothrin (lct) is a new broad-spectrum synthetic pyrethroid insecticide with efficient immediate and persistent activity against a great variety of arthropods harmful both to human and animal health and to vegetal production. in many countries this insecticide has been successfully used in the control of infectious diseases vectors, such as mosquitoes, triatomine bugs (transmitters of trypanosoma cruzi, agent of chagas' disease) and other arthropods. in order to test the immediate and ... | 1992 | 1306993 |
| development of trypanosoma cruzi in the vector in the absence of blood. | first stage nymphs of triatoma infestans and dipetalogaster maximus which had never fed after egg hatching, were allowed to ingest by artificial feeding a blood-free suspension of trypanosoma cruzi trypomastigotes collected from experimentally infected mice. a high percentage of the vectors acquired a normal infection and produced infective stages. the parasite's development in the vector did not require blood but may have needed the presence of unknown factors secreted and/or excreted in the in ... | 1978 | 32750 |
| 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 ... | 1979 | 43891 |
| observations on the feeding and defecation patterns of three triatomine species (hemiptera: reduviidae). | a comparative laboratory study of feeding and defecation behavior of three species of tritomines (rhodnius prolixus, triatoma infestans and t. dimidiata) indicated evident differences among the species and among the different stages of same species. time required for a full blood meal was related to the size of the specimen. insects required an average of 11-28 min for engorgement although some finished within 10 min. t. dimidata frequently interrupted the act of feeding, a probable explanation ... | 1977 | 16468 |
| trypanosoma cruzi: inhibition of metacyclogenesis by mannose. | metacyclogenesis of trypanosoma cruzi epimastigotes was evaluated in a medium supplemented with triatoma infestans intestinal homogenate in the presence of sugars and derivates as are mannose, galactose, fucose, n-acetylglucosamine, mannose 6-p, and fructose 1,6-p at a concentration of 25 mm. only mannose significantly inhibited metacyclogenesis. sodium metaperiodate and trypsin treatment of the intestinal homogenate also inhibited differentiation. in our opinion there exists a proteinic factor ... | 1992 | 1325784 |
| a comparison of rhodnius prolixus, triatoma infestans and panstrongylus megistus in the xenodiagnosis of a chronic trypanosoma (schizotrypanum) cruzi infection in a rhesus monkey (macaca mullatta). | fifth instar rhodnius prolixus, triatoma infestans and panstrongylus megistus were fed on a rhesus monkey (macaca mullatta) with a chronic infection of peru strain trypanosoma cruzi and examined 30 days later for the presence of trypanosomes in the rectum. no correlation could be demonstrated between either blood meal size or sex and the subsequent development of a rectal infection with t. cruzi. as t. infestans and p. megistus were more highly infected than r. prolixus in terms of both percenta ... | 1975 | 814658 |
| [cryopreservation of trypanosoma cruzi in examples of triatoma infestans experimentally infected]. | | 1976 | 794979 |
| chitin synthesis in triatoma infestans and other insects. | in vivo and in vitro synthesis of chitin in triatoma infestans was studied. for in vivo experiments, [14c] sugars were injected through the abdominal wall. maximal incorporation of radioactivity into the cuticle was attained immediately after the ecdysis. the identification of in vivo synthesized chitin was performed by the enzymatic hydrolysis of the alkali-insoluble material from the cuticle with helix chitinase. the main water-soluble compound obtained was n-acetylglucosamine as demonstrated ... | 1976 | 802626 |
| comparative xenodiagnosis with three triatomine species of different hosts with natural and experimental chronic infections with trypanosoma (schizotrypanum) cruzi. | simultaneous xenodiagnosis was made of 29 patients with chronic chagas's disease, six naturally infected opossums (didelphis azarae) and of a rhesus monkey with an experimental chronic infection with trypanosoma (schizotrypanum) cruzi (peru strain). patients and opossums were from an endemic area in the state of bahia, brazil, where panstrongylus megistus is the sole domiciliary vector of the disease to man. various instars of p. megistus triatoma infestans and rhodnius prolixus were used. the p ... | 1978 | 416525 |
| 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. | 1979 | 520485 |
| [spontaneous infection of marmoset-monkeys (sanguinus oedipus) with a trypanosoma cruzi-like-strain, springer 1975. isolation and identification (author's transl)]. | a trypanosoma cruzi-like strain was isolated from marmoset monkeys originating from columbia. the frequency of affected monkeys was up to 32.7%. the parasite density was 10-40 trypomastigote forms per mililiter. monkeys, rats, mice and other small rodentia were found to be susceptible. clinical symptoms or histopathological findings could not be acertained with these trypanosomes even after a 2 1/2 year observation period. the strain behaved as an apathogen in experimental animals. the parasitae ... | 1977 | 416623 |
| search for trypanosoma rangeli in endemic areas of trypanosoma cruzi in argentina and brazil. | because the presence of trypanosoma rangeli in argentina and brazil has not been confirmed, a serach was carried out in man and triatomine insects. fifty-nine of 207 persons (28.5%) were infected when studied with one or more xenodiagnosis (40 triatoma infestans/xenodiagnosis); 0.1% to 13% of 7,821 bugs' feces and 4% of 875 dissected midguts showed t. cruzi in giemsa stained smears. one of 6,980 hemolymph samples and 1/875 salivary glands showed few flagellates which may have originated in the g ... | 1977 | 407809 |
| embryology of triatoma infestans (klug), (hemiptera, reduviidae), a chagas' disease vector. | this study reports the embryogenesis of t. infestans (hemiptera, reduviidae). morphological parameters of growth sequences from oviposition until hatching (12-14 d 28 degrees c) were established. five periods, as percent of time of development (td), were characterized from oviposition until hatching. the most important morphological features were: 1) formation of blastoderm within 7% of td; 2) germ band and gastrulation within 30% of td; 3) nerve cord, limb budding, thoracic and abdominal segmen ... | 1992 | 1342072 |
| immunochemical properties of the antigens of triatoma infestans. | taxonomically related to the cockroach periplaneta americana (pa), triatoma infestans (ti) is an insect that parasitizes two-thirds of argentina and acts as a vector for american trypanosomiasis. the glycoproteins obtained by a sephadex g-150 column fractionation from the whole-body extract prepared with the chitinous structures revealed antigenicity in rabbits, which developed specific igg after 8 weeks of immunization, as detected by several serological techniques. atopic patients living in th ... | 1992 | 1342895 |
| the effect of plastering in a house persistently infested with triatoma infestans (klug) 1934. | the replastering of a house in mambai-goias, brazil, as a measure to wall-in triatoma infestans, is briefly described. unfortunately, because the houseowner would not cooperate the roof tiles were not improved and eventually t. infestans reappeared at this site. a brief discussion follows of some aspects of house improvement in the vigilance phase of a chagas disease control programme. t. infestans appeared in the house described 51 and 258 days after the replastering. | 1992 | 1460702 |
| [dynamics of chagas infection transmission in chile: model and simulation]. | triatoma infestans is the principal vector for chagas disease in chile. although there is enough epidemiological information about human infection, the effect of vector and host (animals and man) populations interrelations over chagas disease prevalence has not been studied. this work studies a determinist mathematical model for the dynamics of chagas disease transmission by triatoma infestans, relating entomological population parameters with infection propagation. the effect of invasion of sus ... | 1992 | 1343375 |
| infectivity to the vector triatoma infestans of dogs infected with trypanosoma cruzi in north-west argentina. | the influence of reinfections on the infectivity to triatoma infestans of dogs seropositive to trypanosoma cruzi was investigated in amamá, north-west argentina, before (1984) and after (1986-1987) elimination of domestic bugs with residual insecticides in 1985. infectivity was quantified by the percentage of infected bugs in each xenodiagnosis of a seropositive dog, i.e. the infective force (if). exposure to reinfection was represented by the domiciliary density of infected bugs and by an index ... | 1992 | 1417201 |
| population dynamics and control of triatoma infestans. | analysis of field populations of triatoma infestans (hemiptera: reduviidae), after a 3-year study, shows that population growth rate is affected by both density-dependent and density-independent mortality. although an equilibrium exists, apparently as a consequence of a density dependent-mechanism, population density fluctuates throughout the year because of the effect of monthly mean minimum temperature as a density-independent source of mortality. simulation studies based on moran curves shows ... | 1992 | 1421494 |
| autogeny in three species of triatominae: rhodnius prolixus, triatoma rubrovaria, and triatoma infestans (hemiptera: reduviidae). | autogeny, the capacity of a female to lay eggs without having ingested any blood meal in the adult stage, was studied in three species of triatominae: triatoma infestans, triatoma rubrovaria, and rhodnius prolixus. when nymphs of t. rubrovaria and r. prolixus were fed chicken blood, autogeny occurred frequently, even with only one meal. in t. infestans autogeny was frequent as well, but demanded at least two nymphal blood meals. total number of autogenic eggs was positively correlated with the b ... | 1992 | 1495041 |
| dispersive flight by triatoma infestans under natural climatic conditions in argentina. | male and female t. infestans were released on two consecutive nights in the salinas of cordoba province, argentina, when air temperatures during the flying period averaged 28.5 degrees c. 136 males (43% of the total released) and 170 females (57%) flew on the first night, and 6 males (18%) and 7 females (27%) on the second. of these, we recovered 23 males and 14 females within 100 m, and a further female within 200 m, all from the first night's release. the remainder appear to have flown more th ... | 1992 | 1600228 |
| feulgen-dna absorption spectrum of euchromatin and constitutive heterochromatin. | when the heterochromatin and euchromatin of triatoma infestans are maximally depurinated, their feulgen-dna spectral profiles exhibit a shoulder at about lambda = 530 nm. the shoulder is especially prominent in the curves of the heterochromatin. it is assumed that this pattern is related to richness in repetitive dna in the heterochromatin, favoring appearance of schiff reagent molecules di-substituted with adjacent apurinic acid aldehydes. | 1978 | 83338 |
| studies of the domestic ecology of triatoma infestans by means of house demolition. | | 1979 | 112663 |
| control of the transmission of chagas' disease in mambai, goias, brazil (1980-1988). | the results of entomologic surveillance conducted after chagas' disease control in mambai, goias, brazil are reported for the years 1985-1988, including a summary of results from 1980 to 1988. a progressive decrease in the incidence of triatoma infestans in houses reached zero in 1988. the threat of secondary vector colonization and the continued need for vigilance are discussed. | 1992 | 1575291 |
| the prophenoloxidase system and in vitro interaction of trypanosoma rangeli with rhodnius prolixus and triatoma infestans haemolymph. | the presence of the prophenoloxidase (propo) system in the haemolymph of rhodnius prolixus and triatoma infestans and the role played by trypanosoma rangeli in the in vitro activation of propo were tested. both r. prolixus and t. infestans whole blood preparations showed a very active propo system. the propo cascade of the two insect species were differentially activated by microbial-derived extracts: laminarin was a better activator of t. infestans haemolymph than of r. prolixus blood, and lipo ... | 1991 | 1956701 |
| the biting rate of triatoma infestans in argentina. | 1. the daily proportion of fed individuals in a population of the reduviid bug triatoma infestans (klug), maintained under natural climatic conditions in experimental chicken houses in central argentina, was estimated from the proportion of bugs retaining colourless urine in the rectum. 2. from the estimates of feeding frequency throughout a 1 year period, it was shown that temperature has a dominant effect on biting rate, but density-dependent effects became apparent during the warmest months. ... | 1991 | 1768924 |
| rapid isolation of metacyclic trypomastigotes of trypanosoma cruzi from feces and urine of the vector. | metacyclic trypomastigotes of trypanosoma cruzi from infected triatoma infestans were isolated and purified by an improved procedure. by using feces and urine of bugs the duration and the number of steps for purification were greatly reduced, thereby minimizing any possible effects on the flagellates. after deae-sephacel column chromatography, a buffer supplemented with bovine serum albumin protected against the slight surface alterations of the trypomastigotes otherwise observed. about 10(7) me ... | 1991 | 1686144 |
| recovery of triatoma infestans populations after insecticide application: an experimental field study. | the capacity of populations of triatoma infestans (klug) (hemiptera: reduviidae) to survive and recover was assessed after application of insecticide (gamma-hch at a rate of 0.5 g a.i./m2) at different seasons. t. infestans populations were maintained in experimental chicken houses under natural climatic conditions in a region of argentina endemic for chagas disease transmitted by these bugs. based on previous studies of t. infestans populations in these habitats, each experimental group was set ... | 1991 | 1722730 |
| vectorial transmission of trypanosoma cruzi: an experimental field study with susceptible and immunized hosts. | the dynamics of vectorial transmission of trypanosoma cruzi and the level of host (guinea pigs) protection after immunization with attenuated parasites (tcc strain) was studied under natural climatic conditions in an endemic region of northern argentina. the experimental design included two guinea pig corrals isolated by mosquito netting. one (controls) had 17 healthy and susceptible adult guinea pigs. the other had 19 guinea pigs immunized with attenuated t. cruzi tcc strain. each corral was co ... | 1992 | 1636879 |
| vector population responses to control interventions. | in 1981, kenyan authorities attempted eradication of tsetse (glossina pallidipes) from the lambwe valley, by sequential aerial spraying of endosulfan. fly populations were reduced by over 99.9% in the main habitats, but recovered to their original levels within one year. in 1986, an argentine research team attempted local elimination of domestic triatominae (triatoma infestans) in an area of santiago del estero. house infestation rates were reduced to an apparent zero, but recovered to pre-contr ... | 1991 | 1793271 |
| chagas disease in north-west argentina: infected dogs as a risk factor for the domestic transmission of trypanosoma cruzi. | the association between household seroreactivity to trypanosoma cruzi in dogs and children and t. cruzi infection rates in domestic triatoma infestans was investigated in 1988-1989 in the rural community of amamá, north-west argentina, where house spraying with residual pyrethroids was carried out in 1985. three years after spraying, a greater reduction of the average t. cruzi prevalence rate in dogs (from 83% to 40%) than in children (from 48% to 30%) was accompanied by a substantial decrease i ... | 1991 | 1801342 |
| density-dependent timing of defaecation by triatoma infestans. | defaecation timing of the triatominae vectors of trypanosoma cruzi directly affects the transmission probability of chagas disease to mammal hosts. experimental studies with fifth instar nymphs of triatoma infestans showed that defaecation time was negatively affected by blood meal size and positively affected by starvation period and bug initial weight. since blood meal size and starvation period are both density-dependent, low density domestic populations of t. infestans would represent a high ... | 1991 | 1801360 |
| the status of transmission of trypanosoma cruzi in an endemic area of argentina prior to control attempts, 1985. | a field survey of transmission of trypanosoma cruzi was carried out in an area which had never been sprayed with insecticide. a population census, mapping and house classification, examination of insects in houses, and a human serological survey were performed. the entomological examination showed that 97% of the houses (433/445) were infested by triatoma infestans and that 31% of the bugs examined were infected with t. cruzi. the level of infection, as well as the number of insects captured, ha ... | 1991 | 1809241 |
| population dynamics of triatoma infestans under natural climatic conditions in the argentine chaco. | using experimental chicken houses at a site in central argentina where the bug triatoma infestans (klug) is endemic, nine populations of this vector of chagas disease were monitored during a 34-month period. bug populations with four chickens as hosts were consistently larger than those with two chickens as hosts. age structure of the bug population followed a similar pattern irrespective of the initial age structure. egg to adult mortality was consistently around 98.5% and there was no consiste ... | 1989 | 2519662 |
| 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. | 1979 | 111570 |
| sylvatic american trypanosomiasis in argentina. trypanosoma cruzi infection in mammals from the chaco forest in santiago del estero. | trypanosoma cruzi infection in sylvatic mammals of the quebracho woods of the eastern part of santiago del estero province, argentina, was studied from october 1984 to december 1987. 301 mammals of 20 different species were caught. t. cruzi, characterized biologically and biochemically, was isolated by xenodiagnosis from 23 of 72 (32%) didelphis albiventris opposums, 2/36 (5.5%) conepatus chinga skunks, and one ferret (galictis cuja). 53 opossum refuges were located and triatomine bugs were foun ... | 1992 | 1566301 |
| acute chagas' disease (trypanosomiasis americana) in acquired immunodeficiency syndrome: report of two cases. | two heterosexual men, aged 31 and 40 years, with the acquired immunodeficiency syndrome and presenting with the acute form of chagas' disease are reported. the first patient, a carrier of hemophilia a, was treated for 20 years with chilean and brazilian cryoprecipitates. this patient acquired both diseases through this medium. the second patient, an inhabitant of northern chile (fourth region), was allegedly bitten by triatoma infestans and was an intravenous drug addict. the hemophilic patient ... | 1992 | 1544668 |
| are dead triatoma infestans a competent vector of trypanosoma cruzi? | after triatoma infestans death, trypanosoma cruzi survived several days, maintaining the ability to infect a vertebrate host. dead bugs from an endemic area collected during an official spraying campaign showed mobile rectal trypanosomes up to 14 days after vector death. two days after vector death 2,760 trypomastigotes were found alive in its rectal material. however, the number of mobile trypomastigotes decreased significantly from the 5th day after death. laboratory proofs with third and fift ... | 1991 | 1842421 |
| [survival and occurrence of molting in triatoma infestans klug (hemiptera, reduviidae) after temperature shock]. | survival and molting occurrence were studied in specimens of triatoma infestans over 30 days after temperature shocks. hyperthermal and hypothermal shocks could be found to affect both survival and molting incidence as a function of temperature and period of the development phase and sex of the specimens. considering the various test conditions, the shock at 0 degree c for 12 h was found to elicit the most deleterious effect, whereas shocks at 40 degrees c and 0 degree c even for 1 h are interpr ... | 1991 | 1843235 |
| the distribution of agglutinins and lytic activity against trypanosoma rangeli and erythrocytes in rhodnius prolixus and triatoma infestans tissue extracts and haemolymph. | haemolymph, heads, salivary glands, crops, midguts, hindguts, and malpighian tubules from rhodnius prolixus and triatoma infestans were extracted in phosphate or tris buffer saline with calcium, and tested for agglutination and lytic activities by microtitration against both vertebrate erythrocytes and cultured epimastigote forms of trypanosoma rangeli. haemagglutination activity against rabbit erythrocytes was found in the crop, midgut and hindgut extracts of t. infestans but only in the haemol ... | 1991 | 1842412 |
| evaluation of the xenodiagnosis of chronic chagas patients infected ten years or over in an area where transmission has been interrupted--iguatama and pains, west minas gerais state, brazil. | to evaluate the results of xenodiagnosis in chronic chagas patients infected for ten years or over in an area where transmission has been stemmed as well as the performance of these tests applied one or more times to determine the presence of the parasite in serum-positive patients for trypanosoma cruzi infection, 570 xenodiagnosis were performed in 246 patients by exposing each patient to 40 triatoma infestans nymphs of 3rd/4th stage once, twice or three times, at 30 days intervals. the 570 xen ... | 1991 | 1842429 |
| [chagas disease in the chilean altiplane. epidemiological, parasitological, and clinical aspects]. | chagas' disease is endemo-enzootic in periurban and rural sections of the first seven (18 degrees 30'-34 degrees 36' south lat.), out of the thirteen political-administrative regions of chile. permanent inhabited localities situated at different altitudes over the sea level (osl) are classified in: coastal settlement (0-1,499 m osl), intermediate settlement (1,500-3,000 m osl) and altiplano settlement (> 3,000 m osl). a total of 1,558 dwellings and their occupants from regions i and ii were surv ... | 1991 | 1844136 |
| [presence of triatoma infestans in relation to various cultural patterns in a rural population of the province of san juan, argentina]. | this paper reports results from a punctual epidemiological survey performed in san juan, at bermejo, a rural village located 100 km east from the provincial capital, in december 1987. the village had been rebuilt after almost complete destruction by an earthquake, in 1977. according to a census performed by local primary health care agents, there were 82 households, where 72 (88%) of them were inhabited, with a total human population of 198 people. forty-eight from those inhabited dwellings (67% ... | 1991 | 1843863 |
| [yielding of xenodiagnosis, according to the number of boxes used in 1,181 persons with chronic chagasic infection diagnosed with indirect hemagglutination reaction]. | a study for evaluation of the yielding of xenodiagnosis (xd) in 1,181 persons with a previous positive indirect hemagglutination test (ihat) for trypanosoma cruzi infection was carried out. the infection of these people was detected during epidemiological surveys performed in rural-periurban and urban sections of the endemo-enzootic area of chagas' disease in chile, which involves the first seven, out of the thirteen political-administrative regions of the country. the sex distribution was 75.0% ... | 1991 | 1844135 |
| antibodies from chagas patients serum bind to the gut epithelial cell surface of triatoma infestans. | serum of chagasic patients with a high title of specific antibodies against t. cruzi antigens, binds epitopes in the midgut and hindgut of the insect vector triatoma infestans free of parasites. these antigens were recognized at ultrastructural level by immunocytochemistry with serum of chagasic patients as first antibody and protein "a"-gold as marker. controls with normal human serum were negative. the positive reaction occurs principally in the apical epithelial portion (microvilli and peritr ... | 1991 | 1844359 |
| [attempts to culturing triatominae in the laboratory using "in vitro" feeding]. | in order to simplify breeding of triatominae in the laboratory, for performing xenodiagnosis and other biologic studies, we tried to feed the insects "in vitro" with citrated or defibrinated blood from commercially abated chicken. two types of efficacy observations were carried out with triatoma infestans: a) analysis of the chaining of successive nymphal stages, viability of satisfactory matching, fertile oviposition and adequate reproduction; b) assessment of viability and infectivity of trypa ... | 1991 | 1844539 |
| [behavior of trypanosoma cruzi strains after passage in different triatominae species]. | to study the influence of the intermediate host stage on the course of mouse infection, trypanosoma cruzi belonging to the peruvian (type i), 12 sf (type ii) and colombian (type iii) strains were passaged through either rhodnius prolixus, panstrongylus megistus or triatoma infestans. t. cruzi metacyclic forms (dose 10(4)) from the different strains were obtained from each bug and inoculated into 8-10 gm mice. comparison was made in mice inoculated with blood forms. parasitaemia curves were plott ... | 1991 | 1845005 |
| [experimental antitriatomic program in santiago]. | the rural migration to urban centers occurred since the 40s in many latin american countries, including santiago the capital city of chile, originated a growing belt of premises built with light poor material (the rests of previous rural habitations, mud, pieces of timber, plastic and cardboard for walls, and cane stalks and artificial clinkstones for roofs) giving raise to many types of slums. this situation facilitated the passive transport of the different instars, including eggs, of triatomi ... | 1991 | 1726919 |
| lethality of triatomines (hemiptera: reduviidae), vectors of chagas' disease, feeding on blood baits containing synthetic insecticides, under laboratory conditions. | a laboratory study was conducted to test the toxicity of synthetic insecticides added to defibrinated sheep blood kept at room temperature and offered as food to the following triatomine species: triatoma infestans, panstrongylus megistus, triatoma vitticeps, triatoma pseudomaculata, triatoma brasiliensis and rhodnius prolixus. the insecticides used, at a concentration of 1 g/l, were: hch, ddt, malathion and trichlorfon, and the lethalithy observed at the end of a 7-day period varied according t ... | 1991 | 1726952 |
| circadian rhythm of egg hatching in triatoma infestans (hemiptera: reduviidae). | the timing of hatching of triatoma infestans (klug) eggs was analyzed by means of time-lapse photography. under a photoperiod of 12:12 (l:d) and constant darkness, maximum eclosion occurred at the end of the subjective night. under constant light, the rhythmicity disappeared. hatching rhythm seems to be maintained by a circadian endogenous oscillator. by hatching close to dawn, when relative humidity is high, insects may avoid excessive water loss. | 1991 | 1941946 |
| the importance of the opossum (didelphis albiventris) as a reservoir for trypanosoma cruzi in bambuí, minas gerais state. | in a survey realized on the sylvatic and peridomestic environments at bambuí county, minas gerais state, 44 (37.9%) out of 116 opossums (didelphis albiventris) captured were found to be naturally infected with trypanosoma cruzi. one hundred and forty three parasite samples were obtained from 43 infected opossums using simultaneously hemoculture, xenodiagnosis (triatoma infestans, panstrongylus megistus and rhodnius neglectus) and examination of anal glands contents. the parasite samples were cha ... | 1991 | 1842405 |
| cultivation of blastocrithidia triatomae (trypanosomatidae) on a cell line of its host triatoma infestans (reduviidae). | blastocrithidia triatomae parasitizes vectors of chagas' disease and is very difficult to cultivate in conventional media. however, co-cultivation with a cell line of its host triatoma infestans (ti-32; in schneider's drosophila medium supplemented with 20% foetal calf serum and 10% tryptose phosphate broth) led to vigorous growth at 24 or 28 degrees c without an adaptation phase. more than 60 primary cultures were initiated successfully without any failures. subcultures could be started immedia ... | 1989 | 2505214 |
| parasite/host-interrelationships of the trypanosomatids trypanosoma cruzi and blastocrithidia triatomae and the reduviid bug triatoma infestans: influence of starvation of the bug. | we have investigated the effects of trypanosoma cruzi and blastocrithidia triatomae on the life span of starved second/third (l2/3), third/fourth (l3/4), and fourth/fifth instars (l4/5) of triatoma infestans, which had been infected in the first instar and fed last in the second, third or fourth instar respectively. the intestines and sometimes also the flagellate populations of dead bugs were examined. in uninfected l2/3 a higher relative humidity prolonged the life span. with a maximal surviva ... | 1989 | 2513786 |
| [household chagasic endemia detected as a consequence of a case of congenital infection]. | during a study on prevalence of parasitic and viral serological markers in pregnant adolescents, a 17-year-old primipara from polpaico, village near santiago, gave birth to a normal male newborn in a santiago hospital. as both of them presented positive an indirect hemagglutination test (ihat) for chagas' disease and the corresponding xenodiagnosis (xd), the infection in the infant was considered to be acquired through the placental route. according to recent epidemiological surveys polpaico is ... | 1991 | 1844139 |
| critical electrolyte concentration of heterochromatin and euchromatin in cells of starved animals. | the critical electrolyte concentration (cec) of chromatin, considered to be the salt concentration at which the phenomenon of metachromasy is completely abolished, when using toluidine blue as the cationic dye and mg2+ ions as inorganic cations, was determined for the euchromatin and chromocentral heterochromatin of cells from starved animals. the objective was to determine variations in cec induced by the starvation stress, which could be related to structural alterations and/or to the composit ... | 1989 | 2699727 |
| binding of lectin-gold conjugates by two trypanosoma cruzi strains in ampullae and rectum of triatoma infestans. | the ampullae and recta of triatoma infestans infected with trypanosoma cruzi were incubated with lectin-gold conjugates of wheat germ agglutinin (wga) and soy bean agglutinin (sba) and investigated by electron microscopy. t. cruzi colonized the whole lumen of the ampullae. the rectal pads with their intensive intracellular membrane system and thin cuticle were often covered by a compact layer of flagellates, whereas the remaining rectal sac- recognizable by a thick layered cuticle - was colonize ... | 1989 | 2575865 |
| trypanosoma cruzi: quantitative studies of development of two strains in small intestine and rectum of the vector triatoma infestans. | this paper describes the development stages and numbers of flagellates of two strains of trypanosoma cruzi living in the small intestine and rectum of the insect, triatoma infestans, during the first 12 weeks postinfection (pi). mainly epimastigotes and occasionally amastigotes and final trypomastigotes developed in the small intestine but after starvation periods of 3 or 4 weeks higher percentages of spheromastigotes including their transitional forms to/from epimastigotes were found. in the re ... | 1989 | 2649388 |
| [seroprevalence of antibodies against trypanosoma cruzi in 13 departments of uruguay]. | in 1985 a study was undertaken of the prevalence of trypanosoma cruzi antibodies in 13 departments of uruguay where transmission of the parasite by the vector triatoma infestans persists. a total of 5,924 serum samples were selected using a probabilistic method--3,840 from individuals over the age of 12 (sample i) and 2,084 from subjects who were 12 years old (sample ii). the population was classified according to place of residence (capital city, non-capital city, suburban area, and rural area) ... | 1989 | 2529870 |
| 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 ... | 1985 | 2862777 |
| 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 ... | 1987 | 2823134 |
| [overview of the epidemiology of chagas' disease in chile]. | chile is a long and narrow country located in the south western coast of south america. chagas' disease exists in the seven first (18 degrees 30'-34 degrees 36' south lat.) of the total of thirteen administrative regions of the country. in the 1982-1990 period a series of studies considering different epidemiological aspects of this parasitic zoonosis has been carried out with the following results: 5,601 rural of periurban dwellings were surveyed for the presence of triatoma infestans (the most ... | 1991 | 1843858 |
| 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 ... | 1986 | 3023131 |
| direct transmission of trypanosoma cruzi between vectors of chagas' disease. | trypanosoma cruzi was transmitted directly between triatomines by cannibalism or coprophagy. different conditions involving cannibalism that excluded coprophagy were studied in dipetalogaster maximus. infections occurred if an uninfected donor bug sucked infectious blood and if this blood was taken up from the stomach by a cannibalistic bug. if the donor was infected and sucked uninfected blood afterwards, the source of the uninfected blood determined the transmission rate: if the uninfected blo ... | 1988 | 2896441 |
| cannibalism and coprophagy are modes of transmission of blastocrithidia triatomae (trypanosomatidae) between triatomines. | transovarial transmission was not detectable among blastocrithidia triatomae-infected triatoma infestans. rather, b. triatomae was transmitted directly between triatomines by cannibalism and coprophagy. cannibalism conditions that excluded coprophagy always resulted in an infection of dipetalogaster maxima. the efficiency of transmission was not influenced by the blood source--mice or chickens--fed to the infected donor bugs although chicken blood lyses the epimastigotes of the stomach populatio ... | 1989 | 2498511 |
| dispersal flight by triatoma infestans in an arid area of argentina. | | 1988 | 2980200 |
| characterization of triatoma virus, a picorna-like virus isolated from the triatomine bug triatoma infestans. | some properties of triatoma virus (trv), a picorna-like virus recently isolated from triatoma infestans, have been studied. electron microscopic observations of purified viral preparations showed the presence of non-enveloped viral particles 30 nm in diameter. the sedimentation coefficient of virus particles was about 165s and the buoyant density in cscl was 1.39 g/ml. the viral genome was composed of one single-stranded rna molecule with an mr of 3 x 10(6). three major polypeptides with mr valu ... | 1988 | 3053988 |
| 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 ... | 1986 | 2882662 |
| probability of transmission of chagas disease by triatoma infestans (hemiptera: reduviidae) in an endemic area of santiago del estero, argentina. | the daily probability (p) of transmission of trypanosoma cruzi to a noninfected human host by an infected triatoma infestans bug was estimated using field data from a 2-year longitudinal study carried out in a rural settlement of 20 households in amamá, santiago del estero, argentina. the following information was used for this purpose: the bug density and the proportion of infected bugs; the bug biting rate and the distribution of bites between humans and animals; the age-specific seropositivit ... | 1990 | 2127382 |
| inhibition of xanthine dehydrogenase from triatoma infestans by some purine analogues. | xanthine dehydrogenase (ec 1.2.1.37) activity was determined in the fat body of the chagas' disease vector triatoma infestans using a system in which phenazine methosulphate was associated with p-iodonitrotetrazolium violet as electron acceptors for the oxidation of the substrate xanthine. under the standard conditions used, xanthine was the substrate of choice. the apparent michaelis-menten constant (km) for xanthine was found to be 0.217 +/- 0.020 mm (mean +/- standard deviation of four indepe ... | 1988 | 3052441 |
| [study of 11 enzymes and formal genetic findings for 19 enzymatic loci in triatoma infestans (hemiptera: reduviidae)]. | | 1985 | 3907524 |
| development of isolated and group-reared first instars of triatoma infestans infected with trypanosoma cruzi. | | 1988 | 3057492 |
| seasonal changes in infectivity of domestic populations of triatoma infestans. | this paper examines the infection rate of trypanosoma cruzi in triatoma infestans, the main vector of chagas disease in argentina and neighbouring countries. the study was carried out in 1986-1987 on 5 houses (ranchos) in the endemic area of central argentina. domestic t. infestans populations were sampled in each season with a constant capture effort (2.5 man-hours/house) using a chemical irritant. the rectal content of the bugs was examined for the presence of t. cruzi. the vector population d ... | 1990 | 2124395 |
| development and interactions of trypanosoma rangeli in and with the reduviid bug rhodnius prolixus. | two strains of trypanosoma rangeli and three strains of rhodnius prolixus were used in various combinations to transmit the trypanosomes via the reduviid bug. a persisting infection in the midgut lumen posterior to the stomach resulted in all 2,500 bugs being third and fourth instars. infectious, metacyclic forms developed exclusively in the salivary glands; forms excreted with bug feces were noninfectious to mice. the midgut epithelium was the main barrier to transmission of the parasite. in on ... | 1990 | 2186407 |
| 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 ... | 1986 | 3088898 |
| myocardial involvement in cavia porcellus naturally infected with trypanosoma cruzi. | this paper describes the myocardial involvement analyzed by histopathological examination in rural cavia porcellus during natural t. cruzi infection. four cavia porcellus of both sexes were bred in a house free of triatoma infestans. in contrast, four animals were born and lived in a rural yard colonized by t. infestans. autopsies were performed at 6-9 months of age, in animals weighing 550 to 750 grams. the naturally infected cavia porcellus presented moderate and severe lymphocyte and plasmocy ... | 1989 | 2487739 |
| 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 ... | 1987 | 2960557 |
| [isolation of trypanosoma cruzi samples by xenodiagnosis and hemoculture from patients with chronic chagas' disease]. | fifty nine chronic chagasic patients were simultaneously submitted to xenodiagnosis and hemoculture for trypanosoma cruzi samples isolations. the xenodiagnosis was done with 40 panstrongylus megistus, triatoma infestans and dipetalogaster maximus nymphs, performing 120 triatomines. groups of 10 insects per specie were dissecated and the intestinal content pooled and examined, after previous trituration and homogenization. the microscopically negative material was seed into lit medium and examine ... | 1989 | 2517566 |
| [ultrastructure of the egg of triatoma infestans klug (heteroptera, reduviidae), morphogenesis of embryonic cuticles and the significance of the envelopes in the transit of water]. | | 1973 | 4572462 |
| 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 ... | 1986 | 3082228 |
| cytogenetics of triatominae: ii-spermatogenesis in hybrid between triatoma infestans and triatoma pseudomaculata (hemiptera, reduviidae) | | 1974 | 4618618 |
| 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 ... | 1987 | 3116867 |
| developmental time and mortality of larvae of triatoma infestans infected with trypanosoma cruzi. | triatoma infestans were infected with trypanosoma cruzi (zymodeme 1) at the first feed after eclosion from the egg; interstadial development times and mortality rates were then recorded until the imaginal moult and compared with those of uninfected controls. no retardation of development occurred in infected bugs and their mean total mortality rate (9%) was only slightly higher than that (6%) of uninfected controls (due solely to 4 additional deaths). this is the first demonstration, under optim ... | 1988 | 3051552 |
| influence of blastocrithidia triatomae (trypanosomatidae) on the reduviid bug triatoma infestans: alterations in the malpighian tubules. | to investigate the cellular basis of our recent observation that the trypanosome blastocrithidia triatomae disturbs excretion in triatoma infestans, we compared the morphology and ultrastructure of malpighian tubules in infected and noninfected bugs. tubules of bugs infected 3-4 months before dissection did not show any morphological alterations in either the upper or lower regions. in fifth instars with a long lasting infection (9-10 months) and a correspondingly retarded larval development, th ... | 1988 | 3148931 |
| trypanosoma cruzi: origin of metacyclic trypomastigotes in the urine of the vector triatoma infestans. | population density and percentage of the different stages of an established infection of trypanosoma cruzi were determined for two parts of the excretory system and for the rectum of fifth instars of triatoma infestans unfed and 4 hr after feeding. these data were also evaluated for feces and urine of the fed bugs. in the first unfed group only small populations of the flagellate occurred in the malpighian tubules and ampullae and not in all bugs. the three rectal populations (rectal lumen and a ... | 1988 | 3280333 |
| [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 ... | 1986 | 3295468 |
| 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 ... | 1986 | 3307956 |