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1.
Mem. Inst. Oswaldo Cruz ; 101(3): 327-329, May 2006. ilus
Article in English | LILACS | ID: lil-431734

ABSTRACT

The mature oocysts of Eimeria lepidosirenis n.sp. are described in faeces removed from the lower region of the intestine of a single specimen of the South American lungfish Lepidosiren paradoxa, from Belém, state of Pará, Amazonian Brazil. Oocysts with endogenous sporulation: spherical to slightly subspherical, 30.8 Î 30.3 µm (28.1 Î 25.9 -33.3 Î 31.8), shape-index (ratio length/width) 1.0, n = 25. Oocyst wall a very thin, single layer approximately 0.74 µm thick, smooth, colourless, with no micropyle and rapidly breaking down to release the sporocysts. Oocyst residuum a bulky ovoid to spherical mass of approximately 20.0 Î 15 µm , composed of fine granules and larger globules and enclosed by a very fine membrane: no polar bodies seen. Sporocysts 15.5 Î 9.0 µm (14.5 Î 8.0 16.0 Î 9.0), shape index 1.7 (1.6-1.8), n = 30, ovoid, with one extremity rather pointed and with a very delicate Stieda body but no sub-Stieda body: sporocyst wall a single extremely thin layer with no valves. Sporocyst residuum a spherical to ovoid mass of approximately 5.0 Î 4.0 µm, composed of fine granules and small globules and enclosed by a very fine membrane. Sporozoites strongly recurved at their ends and apparently with only a single refractile body. Site of development in the host uncertain: no evidence of endogenous stages was found in fresh scrapings and stained smears of the intestinal epithelium.


Subject(s)
Animals , Eimeria/isolation & purification , Oocysts , Fishes/parasitology , Brazil , Eimeria/classification , Feces/parasitology
2.
In. Instituto Evandro Chagas (Ananindeua). Memórias do Instituto Evandro Chagas. Ananindeua, IEC, 2006. p.337-356, ilus. (Produção Cientifica, 8).
Monography in English | LILACS | ID: lil-583702

Subject(s)
Animals , Parasites , Ranidae
3.
In. Instituto Evandro Chagas (Ananindeua). Memórias do Instituto Evandro Chagas. Ananindeua, IEC, 2006. p.323-330, tab. (Produção Cientifica, 8).
Monography in English | LILACS | ID: lil-583704
4.
In. Instituto Evandro Chagas (Ananindeua). Memórias do Instituto Evandro Chagas. Ananindeua, IEC, 2006. p.317-322. (Produção Cientifica, 8).
Monography in English | LILACS | ID: lil-583705
5.
In. Instituto Evandro Chagas (Ananindeua). Memórias do Instituto Evandro Chagas. Ananindeua, IEC, 2006. p.283-315, ilus. (Produção Cientifica, 8).
Monography in English | LILACS | ID: lil-583706

ABSTRACT

During 1960-62 a study on the epidemiology of dermal leishmaniasis due to Leishmania mexicana in British Honduras revealed 18 species of Phlebotomus in the enzootic forest areas. In addition, seven other sandflies remain to be identified and may represent new species. Nine species of Phlebotomus were found commonly to bite man. All were predominantly nocturnal in their feeding habits and, as they were readily infected with L. mexicana, all must be regarded as potential vectors in nature. The infection rates for sandflies fed directly on hamster lesions, at the periphery, and on normal adjacent skin were 95 percent, 48 percent and 0 percent respectively. Maintenance of wild-caught Phlebotomus species is discussed. Best results were obtained by keeping single flies in corked tubes containing a fresh green leaf. The corks had a groove cut throughout their length, to allow air exchange, and all tubes were kept in constant light and at approximately 100 percent relative humidity. Three hundred and thirty-two sandflies, including all the known man-biting species from British Honduras, were fed on the lesions of hamsters and mice infected with both human and rodent strains of L. mexicana. Fifty-two flies were induced to re-feed on volunteers (eight fed a second time and one a third time), in all inflicting a total of 90 probes. Transmission of L. mexicana to man was achieved, by Phlebotomus pessoanus, on one occasion. This insect had fed on the infected hamster only three days and 23 hours previously.The development of L. mexicana in the insect host has been followed by a study of the gut contents and sections of entire sandflies which were fixed at three, six, 12, 24, 36, and 48 hours and 3-5 days after their infective feed. The development is to an anterior station, the leptomonads reaching the proboscis as early as four days after the infecting blood meal...


Subject(s)
Humans , Animals , Leishmania mexicana , Leishmaniasis/transmission , Phlebotomus/parasitology
6.
In. Instituto Evandro Chagas (Ananindeua). Memórias do Instituto Evandro Chagas. Ananindeua, IEC, 2006. p.269-282. (Produção Cientifica, 8).
Monography in English | LILACS | ID: lil-583707
7.
Mem. Inst. Oswaldo Cruz ; 95(1): 43-7, Jan.-Feb. 2000. ilus
Article in English | LILACS | ID: lil-251311

ABSTRACT

The ultrastructure is described of the meronts, microgamonts and young oocyst stages of Isospora hemidactyli of the gecko Hemidactylus mabouia from Belém, PA, north Brazil. The endogenous stages all develop in the nucleus of the gut epithelial cells. The nucleus remains intact up to the latest stages of the parasite's development, but degenerates by the time the oocyst appears. Merogonic division appears to be asynchronous, and some of the differentiated merozoites contained more than one nucleus. Microgamonts conform in structure with those of other eimeriids. Some of the type 2 wall-forming bodies disintegrate into smaller globules and ground substance of lower density.


Subject(s)
Animals , Isospora/ultrastructure , Lizards/parasitology , Brazil , Cell Nucleus , Epithelial Cells/ultrastructure , Intestines/cytology
8.
Mem. Inst. Oswaldo Cruz ; 94(4): 459-66, July-Aug. 1999.
Article in English | LILACS | ID: lil-241555

ABSTRACT

Redescriptions are given of the mature oocysts of Isospora ameivae Carini, 1932, from the teiid lizard Ameiva ameiva, and Isospora hemidactyli Carini,1936 from the gecko Hemidactylus mabouia, in north Brazil. The endogenous stages of the two parasites in the small intestine are described. Those of I. ameivae are intracytoplasmic, whereas those of I. hemidactyli are intranuclear


Subject(s)
Animals , Coccidiosis/parasitology , Intestine, Small/parasitology , Isospora/classification , Lizards/parasitology , Isospora/cytology , Isospora/growth & development , Oocytes/growth & development
9.
Mem. Inst. Oswaldo Cruz ; 93(1): 81-90, Jan.-Feb. 1998. ilus, tab
Article in English | LILACS | ID: lil-201998

ABSTRACT

The oocyst is described of Eimeria peltocephali n. sp. from faeces of the freshwater turtle Peltocephalus dumerilianus from Barcelos, State of Amazonas, Brazil. Sporulation is exogenous and fully developed oocysts are elongate, ellipsoidal or cylindrical, frequently curved to a banana-shape, 54.4 x 19.1 (37.5 -68.7 x 18.7 - 20.0µm), shape-index 2.8 (1.8 - 3.9). The oocyst wall is single thin, colourless layer about 1µm thick, with no micropyle. There is a bulky oocyst residuum, at first spherical to ellipsoidal, 19 x 16 (16.2 -26.2 x 16 - 21.5µm), but becoming dispersed on maturation. There are no polar bodies. The sporocysts, 19.1 x 6.8 (17.5 -21.2 x 6.2 -7.5 µm), shape-index 2.8 (2.3 -3.2), are usually disposed in pairs at each end of the oocyst, and bear an inconspicuous Stieda body in the form of a flat cap. The sporozoites are elongate and slightly curved around the residuum. No refractile bodies were seen. Eimeria molossi n. sp. is described from the molossid bat Molossus ater. Sporulation is exogenous and the mature oocysts are predominantly broadly ellipsoidal, 23.4 x 17.5 (18-30 x 15-22.5 µm), shape-index 1.3 (1-1.6). The oocyst wall is about 2 µm thick, and of three layers: an inner thin, colourless one and two outer layers which are thicker, yellowish-brown, prominently striated and in close apposition. There is no micropyle or oocyst residuum, but one and occasionally two polar bodies are usually present. Sporocysts sre ellipsoidal, 10.2 x 7.5 (10-12.5 x 7.5 µm), shape-index 1.4 (1.3-1.7) with an inconspicuous Stieda body. Endogenous stages are described in the epithelial cells of the small intestine.


Subject(s)
Animals , Eimeria , Chiroptera/parasitology , Turtles/parasitology , Amazonian Ecosystem , Brazil , Oocytes/parasitology
10.
Mem. Inst. Oswaldo Cruz ; 90(5): 589-92, set.-oct. 1995. ilus
Article in English | LILACS | ID: lil-157272

ABSTRACT

Endogenous stages of a Schellackia species are described in histological sections of the intestine of the tree-frog, Phrynohyas venulosa, from North Brazil. Most oocysts sporulate within the epithelial cells of the gut, but a few were detected in the lamina propria.


Subject(s)
Animals , Anura/physiology , Intestines/physiology
11.
Mem. Inst. Oswaldo Cruz ; 90(5): 653-5, set.-oct. 1995. ilus
Article in English | LILACS | ID: lil-157287

ABSTRACT

Blood erythrocytes of Brazilian tree-frogs, Phrynohyas venulosa were found to frequently contain single, small, densely staining inclusions. Electron microscopy showed these to be icosahedral viral particles which measured from 250-280 nm in diameter; they were devoid of an envelope, and thus differed from previously described viruses of frog erythrocytes. The infected erythrocytes lacked a crystalline body.


Subject(s)
Animals , Anura/parasitology , Erythrocytes/physiology , Microscopy, Electron
12.
Mem. Inst. Oswaldo Cruz ; 89(3): 435-43, Jul.-Sept. 1994. tab
Article in English | LILACS | ID: lil-164116

ABSTRACT

Six species of Leishmania are at present known to cause cutaneous and/or mucocutaneous leishamniasis in Brazil, and they are all to be found in the Amazon region of this country. The eco-epidemiology of each is discussed, with the observation that the Amazonian leishmaniases are all zoonoses, with their source in silvatic mammals and phlebotomine sandfly vectors. With man's destruction of the natural forest in southern Brazil, some sandfly species have survived by adapting to a peridomestic or domiciliary habitat in rural areas. Some domestic animals, such as dogs and equines are seemingly now involved in the epidemiology of the disease. No such process has yet been reported in the Amazon region, but may well take place with the continuing devastation of its forest.


Subject(s)
Humans , Ecology , Leishmaniasis, Cutaneous/diagnosis , Animals, Laboratory/parasitology , Animals, Domestic/parasitology , Congress , Leishmaniasis, Visceral/diagnosis
13.
Mem. Inst. Oswaldo Cruz ; 86(1): 41-9, jan.-mar. 1991. ilus, tab
Article in English | LILACS | ID: lil-109262

ABSTRACT

Genomic DNA fragments from males of Psychodopygus wellcomei were isolated and shown to be useful as sensitive diagnostic probles for positively separting individuals of this species from those of Ps. complexus. These two members of the Ps. squamiventris series are found sympatrically in foci of cutaneous leishmaniasis in the hill forests of southern Pará State. Of the two species, only Ps. welcomei is thought to be an important vector of Leishmania braziliensis sensu stricto, buth this is based on circumstantial evidence because of the difficulties of identifying female sandflies wothin the series. The diagnostic probes were isolated from a library of Ps. wellcomei built by ligationg short fragments of Sau 3A-resistricted, genomic DNA into the plasmid vector PUC 18. Differential screening of 1316 library clones with total genomic DNA of Ps. Wellcomei and Ps. complexus identified 5 recombinants, with cross-hybridizing inserts of repetitive DNA, that showed strong specificity for Ps. wellcomei. As little as 0.4% of the DNA extracted from an individual sandfly (=ca. 0.5 namograms) was specifically detected. The diagnostic probes were used to identify as Ps. wellcomei a wild-caught female sandfly found infected with L. braziliensis s.s., providing only the second positive association between these two species


Subject(s)
Animals , Male , Female , DNA Probes , Psychodidae/genetics , Blotting, Southern , Disease Vectors , Genomic Library , Leishmania braziliensis/physiology , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/transmission
14.
Rev. Inst. Med. Trop. Säo Paulo ; 33(1): 18-22, jan.-fev. 1991. ilus
Article in Portuguese | LILACS | ID: lil-107739

ABSTRACT

Fez-se registro, pela primeira vez, do isolamento de Leishmania (V.) lainsoni de um mamifero silvestre, o roedor Agouti paca (Rodentia: Dasyproctidae), no Estado do Para, Brasil. As amostras do parasita foram isoladas da pele, aparentemente integra, de 3 especimes desse roedor, capturados no municipio de Tucurui (ilha de Tocantins), em area que seria inundada pela formacao do lago da hidreletrica construida naquele municipio. Nenhum isolamento foi obtido de visceras de qualquer dos animais. A identificacao das amostras de L. (V.) lainsoni baseou-se na morfologia de amastigotas e promastigotas, no comportamento da infeccao em "hamsters", na analise bioquimica de isoenzimas e, ainda, atraves de testes com anticorpos monoclonais. A natureza inaparente da infeccao nos animais faz supor que o mamifero em questao possa representar um hospedeiro definitivo do parasita na regiao Amazonica.


Subject(s)
Animals , Animals, Wild/parasitology , Leishmaniasis, Cutaneous/parasitology , Leishmania/isolation & purification , Rodentia/parasitology , Brazil , Leishmaniasis, Cutaneous/veterinary
15.
Mem. Inst. Oswaldo Cruz ; 82(3): 421-4, July-Dec. 1987. tab
Article in English | LILACS | ID: lil-47826

ABSTRACT

Foi demonstrado através de infecçäo experimental, que estágios infectivos de Leishmania (L.) amazonensis, capazes de produzir infecçäo na pele do hamster, encontram-se presentes no vetor flebotomíneo Lutzomyia flaviscutellata 15, 25, 40, 49, 70, 96 e 120 horas após o inseto ter recebido sua refeiçäo sangüínea infectiva. Da mesma maneira, foi comprovada a presença de estágios infectivos de L. (L.) chagasi em exemplares do vetor Lu. longipalpis, examinados 38, 50, 63, 87, 110, 135, 171 e 221 horas após o repasto sangüíneo infectivo - através da inoculaçäo em hamster por via intraperitoneal dos flagelados obtidos desses fle botomíneos. A questäo sobre a transmissäo do gênero Leishmania pelo flebotomíneo ser ou näo dependente da presença de promastigotos "metacíclios" na proboscisa do vetor, é discutida


Subject(s)
Cricetinae , Animals , Female , Leishmania donovani/isolation & purification , Leishmaniasis/transmission , Phlebotomy , Longitudinal Studies
16.
Acta amaz ; 161986.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454156

ABSTRACT

A pictorial field guide to the 30 species of sandfly most commonly encountered in Pará State is presented, based on the easily recognised external characters of the length of the 5th palpal segment, thoracic infuscation, abdominal colour and head and body size. In most cases this allows identification to the species. In others, especially with females, it gives an indication of the species, which may then be confirmed with data from more detailed taxanomix studies. This type of field guide helps in teaching, rapid sorting of flies prior to dissection and in acquainting visitors with the variety of species present in a given area.A rapid technique for the taxonomic sorting of unmounted, freshly killed female sandflies is required, prior to the dissection of large numbers of a particular species. Such a method is useful in areas where numerous species occur in studies on natural flagellate infections, age determination and for ecological studies. With the above points in mind a pictorial field guide has been designed that enables the identification of unmounted, unmacerated specimens of the 30 more commonly encountered species of phleboto-mine sandflies (***) in Pará State, North Brazil. It is based on the easily recognised external characters of the length of the 5th palpal segment, thoracic infuscation, ad-dominal colour and proboscis and body size.Taxonomy of male phlebotomine sandflies is based on the structure of the genitalia and, as most of this is external, a wholly external character key is readily made. Female taxonomy, however, is based on the internal character of the cibarium, pharynx and sperma thecae. In order to produce an external character key we therefore return to an unso phisticated "phlebotometry" (see Martins et al., 1978 p. 3 for review), using relative lengths of the proboscis, palpal segments and body, along with the degree of infuscation. Ihis idea is not new; indeed many sandfly specialists presently use external characters to separate certain species (H. Fraiha, R. P. Lane, P. D. Ready, D. G. Young and R. D. Ward personal communications 1983 & 1984).A key used to separate five anthropophillic sandflies by Biagi (1966), in Mexico, was based mainly on palpal segment length and infuscation. Floch and Abonnenc (1952) stressed the use of relative lengths of palpal segments in their keys to the sandflies of French Guiana, and four members of the shannoni group have been similarly separated according to the degree of infuscation by Morales et al. (1982). The use of thoracic infuscation as a reliable character seems to be gaining favour, having been used by young & Fairchild (1974) and Ready & Fraiha (1981). Indeed Chariotis 1974) showed the usefulness of thoracic infuscation to sepenate 7 anthropophillic species, during studies onvesicular stomatitis in Panama. Identification using external characters is essential for work on viral isolations from sandflies, where bulk samples of whole sandflies are used.Perhaps the major advantage of a simple visual guide is for teaching purposes. Technical staff in this lnstitute are able to identify most of the species they encounter without having to use the standard, more unwieldly (and in many cases unavailable) internal character keys, and the guides presented below have allowed rapid species sorting prior to the dissection of sandflies in our leismaniasis study areas (Ryan et at. ,1985).


É apresentado um "levantamento ilustrado" dos 30 flebotomíneos mais comumente encontrados no Estado do Pará, Brasil, usando-se características externas, com as medidas do quinto segmento das palpos, cor do tórax e do abdomen, e medidas da cabeça e do cor po. Com isto é possível, na maioria dos casos, levar à identificação até a espécie. Exis_ tem algumas espécies, entretanto, que são mais difíceis de serem identificadas, particu larmente as fêmeas, havendo nestes casos, necessidade de um exame taxonômico mais deta lhado, para que se possa concluir a identificação. Esta orientação ilustrada é particu larmente útil a técnicos de laboratório, estudantes e entomólogos visitantes.

17.
Article in Portuguese | LILACS | ID: lil-21993

ABSTRACT

Fez-se o registro, na Amazonia, do primeiro caso humano de infeccao cutanea mista determinada por duas especies distintas de Leishmania: a Leishmania brasiliensis e a Leishmania mexicana amazonensis. As duas amostras, em questao foram isoladas de lesoes distintas de um mesmo paciente, e a caracterizacao das especies foi feita com base em observacao de infeccao experimentalem Lutzomya lingipalpis, e eletroforese de isoenzimas em gel de amido. Conclui-se ser de interesse o achado que, combirando com o fato ja conhecido de ausencia de imunidade cruzada entre a maioria das leishmanias, sugere a necessidade do emprego de uma vacina polivalente para a regiao


Subject(s)
Humans , Animals , Cricetinae , Leishmaniasis , Leishmaniasis, Mucocutaneous , Brazil
18.
Mem. Inst. Oswaldo Cruz ; 78(2): 235-6, 1983.
Article in English | LILACS | ID: lil-14074

ABSTRACT

Psychodopygus wellcomei, um vetor comprovado de leishmaniose (muco) cutanea, foi pela primeria vez encontrado fora da Bacia Amazonica, no Estado do Ceara. Evidencia parasitologica e entomologica sugere que a Leishmania braziliensis braziliensis transmitida pelo Ps. wellcomei encontra-se largamente espalhada no "Macico montanhoso do Brasil"


Subject(s)
Animals , Leishmania , Leishmaniasis, Mucocutaneous , Phlebotomus , Brazil
19.
Hiléia méd ; 3(1): 35-40, 1981.
Article in Portuguese | LILACS | ID: lil-6497

ABSTRACT

A leishmaniose na Regiao Amazonica e uma zoonose, sendo o homem apenas hospedeiro acidental, sem qualquer papel na manutencao da infeccao na natureza. A doenca atinge, principalmente, as pessoas que trabalham nas regioes florestais, especialmente aquelas envolvidas em atividades de desmatamento, predominando, portanto, entre a populacao pobre do interior. O controle da doenca e evidentemente dificil em se tratando de matas densas de areas tropicais chuvosas, mas o conhecimento da biologia e dos habitos de alimentacao das varias especies de vetores flebotomineos pode, ate certo ponto, contribuir para a prevencao da infeccao humana. Existe, na Amazonia, uma multiplicidade de especies e subespecies de Leishmania entre mamiferos selvagens, das quais somente algumas atingem a populacao humana. Entre elas a Leishmania mexicana amazonensis, a Leishmania braziliensis braziliensis e a Leishmania braziliensis guyanensis sao associadas a leishmaniose tegumentar humana. Nao existe imunidade cruzada completa entre esses parasitas. Apresenta-se um esquema de classificacao global das leishmanias conhecidas, segundo Lainson e Shaw (1979)


Subject(s)
Leishmania , Leishmaniasis, Mucocutaneous
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