Studies on Trypanosoma rangeli Tejera 1920. VII - Its effect on the survival of infected triatomine bugs

The pathological effects of Trypanosoma rangeli on Rhodnius prolixus and R. robustus, and the relation of mortality to infection, were studied under laboratory conditions. Frequent observations revealed that when the first instar nymphs of R. prolixus and R. robustus were infected with T. rangeli, survival of the bugs during the stages of development to the adult stage decreased. This decrease was statistically significant when compared with uninfected control-bugs, indicating that T. rangeli is pathogenic for both species of triatomine. In R. prolixus the most affected nymphal stages were the first, second and fifth instars, where a higher mortality was also observed. In R. robustus a progressive increase of the mortality from the first to fifth instars, was observed. The pathogenicity of T. rangeli as measured by overall mortality was the same in R. prolixus and R. robustus. The possible pathogenic mechanism of T. rangeli in triatomine-bugs and its epidemiological implications, are discussed.

Estudios sobre Trypanosoma rangeli Tejera, 1920: VIII. Respuesta a las reinfecciones en dos mamíferos

Bajo condiciones experimentales se estudia el curso de la infección primaria y la respuesta a las reinfecciones por Trypanosoma rangeli en ratones albinos y Didelphis marsupialis. Durante el curso de la infección primaria en ratones, se observa una parasitemia relativamente baja y de corta duración. Los mismos muestran durante la primera reinfección una parasitemia escasa de cuatro días de duración, siendo resistentes a las sucesivas reinfecciones con T. rangeli. Los ejemplares de D. marsupialis exhiben una parasitemia de más larga duración, pero con un nivel de parásitos sanguícolas mucho menor que el detectado en el modelo ratón, siendo la respuesta a las reinfecciones similar a la observada en ratones. Se detectan anticuerpos hemaglutinantes en los sueros inmunes de ratones y Didelphis marsupialis, sometidos a la reinfección por T. rangeli. Se especula sobre la posible acción sinérgica de una respuesta inmune en el sitio de deposición en contra de las formas metacíclicas de T. rangeli y la acción de anticuerpos circulantes en contra de las formas sanguícolas, para explicar la resistencia de ambos modelos a las reinfecciones por T. rangeli.

Canine Visceral Leishmaniasis in Rio de Janeiro, Brazil: clinical, parasitological, therapeutical and epidemiological findings (1977-1983)

Forty dogs from the periphery of the city of Rio de Janeiro were studied. All dogs where diagnosed as positive for leishmaniasis either parasitologically and/or serologically. Among them, 19 came from areas where only Visceral Leishmaniasis (VL) occurs (Realengo, Bangu, Senador Camará). Clinical signs of the disease were seen in 36.8% of the cases, including emaciation - 100%, lymphadenopathy and depilation - 85.7%. The other 21 dogs came from an area (Campo Grande) where both diseases (VL, and American Cutaneous Leishmaniasis - ACL) occur. Clinical signs of the disease, mainly cutaneous or mucocutaneous ulcers were seen in 76.2% of the cases. Leishmania parasites were found in 39 cases: 22% in viscera, 42.5% in viscera and normal skin and 35% in cutaneous or mucocutaneous ulcers. All the Leishmania stocks isolated from dogs which came from Realengo, Bangu, Senador Camará (VL area), and from Campo Grande (VL + ACL area) were characterized as L. donovani (except in one case) according to their schizodeme, zymodeme and serodeme. The only stock characterized as L. b. braziliensis, was isolated from the lymph node of a dog from Campo Grande with visceral disease and without skin lesions. Antimony therapy attempted in eight Leishmania donovani positive dogs was unsuccessful.

Studies on Trypanosoma rangeli Tejera, 1920: IX. Course of infection in different stages of Rhodnius prolixus

Frequent individual observations od different stages of Rhodnius prolixus exposed to Trypanosoma rangeli, revealed a higher susceptibility to infection in the bugs exposed during the two first instars. The mortality rate in infected bugs was significantly higher than in controls, indicating that the parasite was responsible for the majority of deaths. An analysis of the mortality distribution, per instar, is presented. Statistical analysis of deaths among the different infected instars, showed that T. rangeli produces its pathological effect in any stage of R. prolixus independently of its susceptibility to the parasite. The survival to adult decreased in all the infected instar bugs. A significant longer time to reach the adult stage was observed in the infected bugs when compared with controls, excepting for specimens exposed in the third instar. The epidemiological significance of the present results is discussed.

A patologia da esquistossomose mansoni no coelho

Coelhos com infecções maciças (20.000 cercárias) pelo Schistosoma mansoni desenvolvendo dentro de três a dez meses intensas e peculiares lesões no sistema porta intrahepático; estas consisten en endoflebite poliposa e endoflebite granulomatosa oclusiva, que evoluem para a cicatrização, com hialinização dos polipos endoteliais e com ectasia vascular, ou com trombose, organização e recanalização. Nos períodos tardios, estas lesões se acompanham de fibrose periportal, septal e de espessamento da trama reticular intra-parenquimal. Embora podendo ser bem intensas, tais lesões têm um caráter focal, pois se relacionam com grupos de vermes alojados em alguns segmentos da veia porta, não determinam hipertensão porta, nem têm semelhanças com as lesões da esquistossomose humana. Os granulomas periovulares quase não aparecem no fígado, mas se formam bem nos intestinos, especialmetne nos dois ou três primeiros meses após a infecção. A patologia da esquistossomose no coelho tem, portanto, aspectos peculiares, os quais merecem ser bem conhecidos, uma vez que este modelo pode se revelar de interesse para estudantes dos imunológicos e imunopatológicos.

Descriptions of syntypes of Brumptamyia brumpti (Lsrrousse, 1920) (Diptera: Psychodidae-Phlebotominae)

The male and female of Brumptomyia brumpti (Larrousse, 1920), the type species of the genus Brumptomyia França & Parrot, 1921 (Diptera: Psychodidae - phlebotominae) are redescribed from syntypes in the British Museum (Natural History).

Trypanosoma rangeli (Tejera, 1920) isolated from a sylvatic rodent (Echimys dasythrix) in Santa Catarina island, Santa Catarina state: first report of this trypanosome in southern Brazil

A trypanosome strain isolated from a sylvatic rodent (Echimys dasythrix) from Santa Catarina Island (Santa Catarina State, Brazil) was characterized by the following methods: experimental transmission and development in invertebrate hosts, morphometry, cross protection, complement sensitivity, lectin agglutination and isoenzyme profiles. Comparasions were made with standard Trypanosoma cruzi and T. rangeli strains. All methods except isoenzyne analysis led to the identification of the isolate as T. rangeli. The isoenzyme differences found could be explained on the basis of polymorphism. Therefore this is the first report of T. rangeli in southern Brazil, increasing the geographical distribution of this parasite.

Trypanosoma rangeli (Tejera, 1920): observations upon pleomorphism

Metatrypomastigotes of Trypanosoma rangeli Tejera, 1920, harvested from LIT medium, were inoculated i.p. or s.c. into 6, 16, and 26g NMRI mice, these representing increasing degrees of immunological maturity. In all cases, similar pleomorphic patterns were observed. Four morphobiometrically differentiable types of trypanosome were encountered in an overlapping temporal sequence. These observations, taken in comparison with those on pleomorphism in this and other species of Trypanosoma by other workers, are consistent with the hypothesis that the pleomorphic types represent the natural development of the parasite, rather than the result of the immune response of the mammal host. Small, slender trypanosomes prevalent at the onset of the parasitemia either reinvade the tissue cells for relatively limited subsequent generations of tissue reproduction, or else differentiate toward the forms that are only capable of colonizing the insect vector.

First report of Lutzomyia (Nyssomyia) umbratilis Ward & Frahia, 1977 outside of Amazonian Region, in Recife, State of Pernambuco, Brazil (Diptera: Psychodidae: Phlebotominae)

Lutzomyia umbratilis, a known vector of Leishmania guyanensis in the north of Amazon basin, has been exclusively found in the Amazonian region. Here we report for the first time the occurrence of this species in northeastern Brazil. The epidemiological importance of the occurrence of this species in the Atlantic Forest is commented.

Trypanosoma (Herpetosoma) rangeli Tejera, 1920: an updated review

Trypanosoma rangeli, a parasite generally considered non-pathogenic for man, is the second species of human trypanosome to be reported from the New World. The geographical distribution of T. rangeli often overlaps with that of T. cruzi, the same vertebrate and invertebrate hosts being infected. Their differentiation thus becomes of real, practical importance, particularly as they share approximately half the antigenic determinants recognized by the humoral response. Little is known about the life cycle of T. rangeli in the vertebrate host, although thousands of human and wild animal infections have been reported. Recent studies have revealed 2 major phylogenetic lineages in T. rangeli having different characteristics, thus leading to better understanding of the epidemiology and interactions with this parasite's vertebrate hosts and triatomine vectors. Based on further genetic characterization analysis, the authors have proposed 2 alternative hypotheses and consider that T. rangeli could have had clonal evolution or have been subjected to speciation processes.

First report on the occurrence of Trypanosoma rangeli Tejera, 1920 in the state of Ceará, Brazil, in naturally infected triatomine Rhodnius nasutus Stål, 1859 (Hemiptera, Reduviidae, Triatominae)

The aim of this work was to identify and report the occurrence of Trypanosoma rangeli and Trypanosoma cruzi in naturally infected Rhodnius nasutus (Hemiptera, Reduviidae, Triatominae) in the state of Ceará, Brazil. Triatomines feces, salivary glands, and hemolymph were collected for fresh examination, and specific detection of T. rangeli and T. cruzi DNA by polymerase chain reaction was carried out. The specific characterization of these two parasites showed the simultaneous presence of both parasites in two (7.7%) of the 26 positive insects. Our results provide further knowledge on the geographical distribution of T. rangeli in Brazil.

Fiscalização e formação das parteiras em São Paulo (1880-1920)

Este artigo faz parte de uma pesquisa mais ampla realizada em nível de Pós-Doutuorado na Escola de Enfermagem da USP (1999-2000), intitulada «Caminhos Cruzados: os cursos para formação de parteiras e enfermeiras em São Paulo (1880-1971)» que teve por objetivo refletir sobre as atribuições de parteiras e enfermeiras obstétricas e a exclusão dessas profissionais na assistência ao parto no decorrer do século XX. O artigo se detém nos primeiros cursos para formação de parteiras e na fiscalização da profissão, apontando que no início do século XX, já se pode perceber uma associação entre parteiras e enfermeiras, não apenas em alguns cursos para formação profissional, como também no cotidiano de trabalho. Passa a existir a expectativa de que a parteira fosse também enfermeira.

Propagandas de remédio na imprensa ilustrada e a imagem da enfermeira brasileira (1920-1925)

Estudo histórico-social sobre efeito simbólico das propagandas de remédios protagonizadas por mulheres com representações objetais utilizadas por enfermeiras, veiculadas na Revista Fon-Fon, que descreve as propagandas de remédios veiculadas neste meio de comunicação; analisa as representações objetais da imagem da enfermeira presente nessas propagandas e discute o efeito simbólico dessas representações para o consumo do remédio pela sociedade brasileira. As fontes documentais foram escritas, iconográficas e literatura referentes à História do Brasil, da Imprensa, da Propaganda e da Enfermagem. As propagandas de remédios analisadas, mediante uma matriz de análise baseada em conceitos da semiótica, derivam da Revista Fon-Fon. O estudo evidenciou que as propagandas analisadas investiram em representações objetais utilizadas pelas enfermeiras, de modo a obterem credibilidade em relação ao medicamento anunciado.

Participação americana na formação de um modelo de enfermeira na sociedade brasileira na década de 1920

Estudo histórico-social cujos objetivos são: descrever as circunstâncias que determinaram a participação de enfermeiras norte-americanas na formação da enfermeira brasileira e analisar o processo de implantação de rituais institucionais como estratégia de luta simbólica, para conferir visibilidade à profissão de enfermeira e discutir os efeitos simbólicos dos rituais institucionais para a consagração de um modelo de enfermeira para a sociedade brasileira da época. Fontes primárias: documentos escritos e fotográficos relativos à temática do estudo. A leitura do corpus documental comportou a análise dos símbolos que distinguiram e situaram as hierarquias das ações, bem como as estratégias empreendidas pelas enfermeiras norte-americanas, no sentido de implantar um novo modelo de enfermeira para a sociedade brasileira, coerente com o modelo das escolas de enfermagem norte-americanas. Os rituais institucionais, protagonizados ou testemunhados por personagens prestigiosas da história do Brasil e da enfermagem, foram fundamentais para a construção da identidade profissional.