Estudo do ciclo evolutivo do "Schizotrypanum Cruzi" em cultura de tecidos de embrião de galinha
TL;DR: The authors were able to follow the complete cycle of the parasite, observing its classic evolution: transformation into leishmania, multiplication by binary division, transformation into crithidia and finally into trypanosome.
Abstract: Chick embryo tissue cultures were smeared with Schizotrypanum from different sources. The cultures were inoculated with flagellates from blood-agar cultures and in one instance from blood of an infected guinea-pig. Carrels technique of tissue culture, with slight modifications, was employed. The tissue used were spleen, myocardium, liver, epithelium of the iris, spinal ganglion and monocytes from chicken blood. In all these tissues the flagellate developed easily, parasitizing different types of cells: fibroblasts, histiocytes, macrophages, epithelial cells, cells of the nervous system, etc. The authors were able to follow the complete cycle of the parasite, observing its classic evolution: transformation into leishmania, multiplication by binary division, transformation into crithidia and finally into trypanosome. They also observed forms of the parasite which possibly developed directly from leishmania to trypanosome without apparently going through the crithidia stage. They succeeded in infecting a white mouse with a human strain of S. cruzi after passage through tissue culture. The authors also pointed out different phenomena observed in the relations between the cells and the parasites.
Citations
More filters
TL;DR: Chicken macrophages, obtained by cultivation of blood monocytes, were infected with epimastigote and bloodstream trypomastigotes of the Y and the CL strains of Trypanosoma cruzi to discuss differences between parasites of the two strains and between the two developmental stages of the T. cruzi lifecycle.
Abstract: Chicken macrophages, obtained by cultivation of blood monocytes, were infected with epimastigote and bloodstream trypomastigotes of the Y and the CL strains of Trypanosoma cruzi. The percentage of infected cells and the mean number of parasites per cell were determined after 2, 6, 12 and 24 h of parasite–cell contact. After 6 h of contact about 80% and 40% of the macrophages were infected by trypomastigotes of the Y and CL strains respectively. After longer periods of contact almost all macrophages were infected by Y trypomastigotes while only about 60% were infected by those of the CL strain. After 2 h of contact almost all macrophages were infected by CL epimastigotes while only about 50% were infected by Y epimastigotes. After 6 h of contact almost all macrophages were infected by epimastigotes of both strains. These results are discussed taking into consideration differences between parasites of the two strains and between the two developmental stages of the T. cruzi life-cycle.
14 citations
TL;DR: Fourteen to twenty days after the infection of seven white mice with Trypanosoma Cruzi, the myocardium of these animals was studied by both light and electron microscopy and revealed a subacute Chagas' myocarditis in which most of the parasites were found in macrophages.
Abstract: Von sieben weisen Mausen wurde der Herzmuskel 14–20 Tage nach einer einmaligen Infektion mit Trypanosoma Crazi lichtmikroskopisch und elektronenmikroskopisch untersucht. Lichtmikroskopisch fand sich das Bild einer subakuten Chagas-Myocarditis, bei der die meisten Parasiten in Makrophagen und nur relativ wenige in den Herzmuskelzellen selbst angetroffen wurden. Elektronenmikroskopisch zeigten Herzmuskelzellen, die einzelne Parasiten in der Leishmaniaform enthielten, nur auffallend geringe Veranderungen. In der Umgebung rupturierter parasitarer Pseudocysten oder im Bereich interstitieller Zellinfiltrate zeigten die Herzmuskelzellen eine unter dem Sarkolemm beginnende hochgradige Schwellung des endoplasmatischen Reticulums oder ein Zellodem mit Auflosungserscheinungen an den Myofibrillen. In anderen Herzmuskelzellen waren die Mitochondrien hochgradig geschwollen. Die Blutcapillaren zeigten entweder ein Zellodem des Endothels mit starker Einengung der Gefaslichtung oder sie enthielten kleine Thromben. Die Veranderungen der Herzmuskelzellen sind teilweise als Folge einer von den Parasiten (Trypanosoma Cruzi) ausgehenden toxischen Wirkung und teilweise als Folgen einer auf Zirkulationsstorungen im Bereich der Blutcapillaren beruhenden Hypoxie anzusehen.
13 citations
TL;DR: Examples of how advances in microscopy have challenged established conceptual models of the intracellular life cycles of Leishmania spp.
Abstract: The literature has identified complex aspects of intracellular host-parasite relationships, which require systematic, nonreductionist approaches and spatial/temporal information. Increasing and integrating temporal and spatial dimensions in host cell imaging have contributed to elucidating several conceptual gaps in the biology of intracellular parasites. To access and investigate complex and emergent dynamic events, it is mandatory to follow them in the context of living cells and organs, constructing scientific images with integrated high quality spatiotemporal data. This review discusses examples of how advances in microscopy have challenged established conceptual models of the intracellular life cycles of Leishmania spp. and Trypanosoma cruzi protozoan parasites.
9 citations
01 Jan 1972
TL;DR: Die amerikanische Trypanosomose war ursprunglich eine auf Wirbellose (Triatominae) beschrankte Parasitose, die sich nach Einbeziehung von Vertebraten in den parasitaren Entwicklungscyclus auf zahlreiche Wirbeltierarten ausdehnte.
Abstract: Die amerikanische Trypanosomose, verursacht durch das Trypanosoma cruzi (Chagas, 1909), war ursprunglich eine auf Wirbellose (Triatominae) beschrankte Parasitose, die sich nach Einbeziehung von Vertebraten in den parasitaren Entwicklungscyclus auf zahlreiche Wirbeltierarten ausdehnte. Nachdem sich einige Ubertrager an die menschlichen Behausungen angepast hatten und dadurch auch der Mensch in den Entwicklungskreislauf des Trypanosoms eingeschlossen worden war, nahm sie schlieslich den Charakter einer typischen Zoonose an (Chagas, 1912).
2 citations