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  1. Article: Trichosporon asahii secretes a 30-kDa aspartic peptidase

    Valle, Roberta S / André L.S. Santos / Cátia L. Sodré / Lívia S. Ramos / Marcos Dornelas-Ribeiro / Mariangela Ziccardi / Marta H. Branquinha / Vanessa J. Reis

    Microbiological research. 2017 Dec., v. 205

    2017  

    Abstract: Trichosporon asahii is a fungal opportunistic pathogen that causes superficial and deep-seated infections presenting high mortality. Very little is known about the virulence attributes produced by this fungus. Herein, aspartic peptidase production was ... ...

    Abstract Trichosporon asahii is a fungal opportunistic pathogen that causes superficial and deep-seated infections presenting high mortality. Very little is known about the virulence attributes produced by this fungus. Herein, aspartic peptidase production was identified in Brazilian clinical isolates of T. asahii by different methodologies. Initially, T. asahii strain 250 (from skin lesion) was inoculated in both liquid and solid culture media containing bovine serum albumin (BSA) as the sole nitrogenous source. A translucent halo around the fungal colony was observed from the 5th day of culture. The cell-free culture supernatant revealed that soluble BSA was hydrolyzed along the growth, generating low molecular mass polypeptides as observed by electrophoresis. Subsequently, the secretions from four clinical strains of T. asahii were analyzed by BSA-SDS-PAGE and a single proteolytic band of 30-kDa was detected under acidic pH at 37°C. The secreted aspartic peptidase of T. asahii efficiently cleaved the cathepsin D peptide substrate, but not the substrates with specificity to HIV-1 peptidase and rennin. The capability to cleave either cathepsin D substrate in a fluorogenic assay or BSA immobilized within a gel matrix varied according to the T. asahii isolate. T. asahii extracellular peptidase activity was strongly inhibited by pepstatin A and HIV peptidase inhibitors, classifying it as an aspartic-type peptidase. Human serum albumin, mucin, non-immune immunoglobulin G and gelatin induced, in different levels, the secretion of this aspartic peptidase. With these results, T. asahii must be included in the list of many human fungal opportunistic pathogens able to secrete an aspartic-type peptidase.
    Keywords bovine serum albumin ; cathepsin D ; cell free system ; chymosin ; culture media ; electrophoresis ; fungi ; gelatin ; Human immunodeficiency virus 1 ; human serum albumin ; humans ; immunoglobulin G ; molecular weight ; mortality ; mucins ; pH ; polypeptides ; proteolysis ; secondary infection ; secretion ; skin lesions ; Trichosporon asahii ; virulence
    Language English
    Dates of publication 2017-12
    Size p. 66-72.
    Publishing place Elsevier GmbH
    Document type Article
    ZDB-ID 1189614-0
    ISSN 1618-0623 ; 0944-5013
    ISSN (online) 1618-0623
    ISSN 0944-5013
    DOI 10.1016/j.micres.2017.08.015
    Database NAL-Catalogue (AGRICOLA)

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  2. Article ; Online: Polymorphism in Trypomastigotes of Trypanosoma (Megatrypanum) minasense in the blood of experimentally infected squirrel monkey and marmosets

    Mariangela Ziccardi / Ricardo Lourenço-de-Oliveira

    Memórias do Instituto Oswaldo Cruz., Vol 94, Iss 5, Pp 649-

    1999  Volume 653

    Abstract: Experimental infections by Trypanosoma (Megatrypanum) minasense were performed in primates - Saimiri sciureus and Callithrix penicillata - with the objective of searching for morphological variations of the blood trypomastigotes with respect to hosts and ...

    Abstract Experimental infections by Trypanosoma (Megatrypanum) minasense were performed in primates - Saimiri sciureus and Callithrix penicillata - with the objective of searching for morphological variations of the blood trypomastigotes with respect to hosts and time of infection. We carried out morphological and morphometric analysis of blood trypomastigotes. Illustrations are given. Both the squirrel monkey and marmoset became infected after the injection of blood trypomastigotes of T. minasense , although the parasitaemia were briefer in the squirrel monkey. The parasites detected in the later host were narrower and shorter than those found in the inoculated marmoset. In the marmoset, the blood stream parasites derived from culture metacyclic trypomastigotes were considerably smaller than those derived from the inoculation of infected blood. Stronger evidence of polymorphism was found when, at the same time of infection, the blood trypomastigotes found in squirrel monkey had smaller length, body width and the distance from posterior end of the body to the kinetoplast almost four times smaller than the parasite found in the marmoset. Therefore, conflicting results on morphology and morphometry of T. minasense obtained by previous investigators could be due to polymorphism.
    Keywords Trypanosoma minasense ; Callithrix penicillata ; Saimiri sciureus ; polymorphism ; experimental infection ; Arctic medicine. Tropical medicine ; RC955-962 ; Microbiology ; QR1-502
    Subject code 630
    Language English
    Publishing date 1999-09-01T00:00:00Z
    Publisher Instituto Oswaldo Cruz, Ministério da Saúde
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Morphological Features of Trypanosomes from Squirrel Monkeys from the Brazilian Amazon

    Mariangela Ziccardi / Ricardo Lourenço-de-Oliveira

    Memórias do Instituto Oswaldo Cruz., Vol 93, Iss 1, p

    1998  Volume 301

    Abstract: A morphometric analysis of blood trypomastigotes identified as Trypanosoma minasense, T. saimirii, and T. rangeli harbored by squirrel monkeys from the Brazilian Amazon was performed. Additionally, morphological and biological comparative analyses were ... ...

    Abstract A morphometric analysis of blood trypomastigotes identified as Trypanosoma minasense, T. saimirii, and T. rangeli harbored by squirrel monkeys from the Brazilian Amazon was performed. Additionally, morphological and biological comparative analyses were conducted of T. saimirii-like and T. rangeli development forms from haemoculture and xenodiagnosis. Illustrations are given of blood trypomastigotes as well as of developing flagellates in triatomine and axenic culture. Mean values of blood trypomastigotes of T. saimirii differ statistically from those of T. rangeli in only two out of ten morphological characters measured, and ranges overlapped. The developing forms of T. saimrii-like parasites were essentially identical in both xenodiagnosis and haemoculture to those of T. rangeli. Trypanosomes confirmed as T. rangeli were transmitted to mice by the bites of the great majority of triatomines that fed on T. saimirii-like infected monkeys. We conclude that, based on morphology and on the development in triatomine bugs and haemoculture, T. saimirii should not be considered a distinct species. We therefore propose T. saimirii to be a junior synonym of T. rangeli
    Keywords Trypanosoma rangeli ; Trypanosoma saimirii ; Trypanosoma minasense ; trypanosomes measurements ; trypanosomatid flagellates ; neotropical primates ; culture ; xenodiagnosis ; Arctic medicine. Tropical medicine ; RC955-962 ; Microbiology ; QR1-502
    Language English
    Publishing date 1998-01-01T00:00:00Z
    Publisher Instituto Oswaldo Cruz, Ministério da Saúde
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: The Infection Rates of Trypanosomes in Squirrel Monkeys at Two Sites in the Brazilian Amazon

    Mariangela Ziccardi / Ricardo Lourenço-de-Oliveira

    Memórias do Instituto Oswaldo Cruz., Vol 92, Iss 4, p

    1997  Volume 465

    Abstract: A study was conducted to determine the prevalence of natural infections by trypanosome species in squirrel monkeys: Saimiri sciureus (Linnaeus) and Saimiri ustus (Geoffroy) caught respectively near 2 hydroelectric plants: Balbina, in the State of ... ...

    Abstract A study was conducted to determine the prevalence of natural infections by trypanosome species in squirrel monkeys: Saimiri sciureus (Linnaeus) and Saimiri ustus (Geoffroy) caught respectively near 2 hydroelectric plants: Balbina, in the State of Amazonas, and Samuel, in the State of Rondônia, Brazil. A total of 165 squirrel monkeys were examined by thick and thin blood smears (BS), haemocultures and xenodiagnosis: 112 monkeys, 67.9%,(being 52.7% with mix infections) were positive to trypanosomes. Four species of trypanosomes were found in monkeys from the 2 areas: Trypanosoma (Tejeraia) rangeli Tejera or T. rangeli-like parasites in 58 squirrel monkeys (35.2%), Trypanosoma (Megatrypanum) minasense Chagas in 55 (33.3%), Trypanosoma (Herpetosoma) saimirii Rodhain or T. saimirii-like parasites in 53 (32.1%) and Trypanosoma (Schizotrypanum) cruzi Chagas in 17 (10.3%). As T. saimirii resembles T. minasense in blood-stream trypomastigotes and T. rangeli in cultural forms and in this survey almost all monkeys presenting trypanosomes morphologically indistinguishable from T. saimirii and/or T. minasense in BS were found through xenodiagnosis and/or haemoculture to be infected by T. rangeli, we suggest that the validity of T. saimirii needs to be evaluated
    Keywords Trypanosoma saimirii ; Trypanosoma rangeli ; Trypanosoma cruzi ; neotropical primates ; trypanosomes ; trypanosomatid flagellates ; Brazil ; Arctic medicine. Tropical medicine ; RC955-962 ; Microbiology ; QR1-502
    Language English
    Publishing date 1997-07-01T00:00:00Z
    Publisher Instituto Oswaldo Cruz, Ministério da Saúde
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: The haemoculture of Trypanosoma minasense chagas, 1908

    Mariangela Ziccardi / Ricardo Lourenço-de-Oliveira / Ricardo Nogueira

    Memórias do Instituto Oswaldo Cruz., Vol 91, Iss 4, Pp 501-

    1996  Volume 505

    Abstract: Trypanosoma minasense was isolated for the first time in blood axenic culture from a naturally infected marmoset, Callithrix penicillata, from Brazil. The parasite grew profusely in an overlay of Roswell Park Memorial Institute medium plus 20% foetal ... ...

    Abstract Trypanosoma minasense was isolated for the first time in blood axenic culture from a naturally infected marmoset, Callithrix penicillata, from Brazil. The parasite grew profusely in an overlay of Roswell Park Memorial Institute medium plus 20% foetal bovine serum, on Novy, McNeal and Nicolle medium (NNN) , at 27°C, with a peak around 168 hr. The morphometry of cultural forms of T. minasense, estimates of cell population size and comparative growth in four different media overlays always with NNN, were studied. The infectivity of cultural forms to marmosets (C. penicillata and C. jacchus) and transformation of epimastigotes into metacyclic-like forms in axenic culture in the presence of chitin derivates (chitosan) were evaluated.
    Keywords Trypanosoma minasense ; neotropical primates ; trypanosomes ; marmosets ; trypanosomatidae flagellates ; culture ; Brazil ; Microbiology ; QR1-502 ; Science ; Q ; DOAJ:Microbiology ; DOAJ:Biology ; DOAJ:Biology and Life Sciences ; Arctic medicine. Tropical medicine ; RC955-962 ; Special situations and conditions ; RC952-1245 ; Internal medicine ; RC31-1245 ; Medicine ; R ; DOAJ:Internal medicine ; DOAJ:Medicine (General) ; DOAJ:Health Sciences
    Language English
    Publishing date 1996-08-01T00:00:00Z
    Publisher Instituto Oswaldo Cruz, Ministério da Saúde
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Trypanosomes of non-human primates from the National Centre of Primates, Ananindeua, State of Pará, Brazil

    Mariangela Ziccardi / Ricardo Lourenço-de-Oliveira / Ralph Lainson / Maria do Carmo de Oliveira Brígido / José Augusto Pereira Carneiro Muniz

    Memórias do Instituto Oswaldo Cruz., Vol 95, Iss 2, Pp 157-

    2000  Volume 159

    Abstract: Trypanosome infections were sought in 46 non-human primates captured principally in Amazonian Brazil. Twenty-two (47.8%) were infected with four Trypanosoma species: T. cruzi, T. minasense, T. devei and T. rangeli. These preliminary results confirmed the ...

    Abstract Trypanosome infections were sought in 46 non-human primates captured principally in Amazonian Brazil. Twenty-two (47.8%) were infected with four Trypanosoma species: T. cruzi, T. minasense, T. devei and T. rangeli. These preliminary results confirmed the high prevalence and diversity of natural infections with trypanosomes in primates from Brazilian Amazon and were the first formal record of simian infections with trypanosomes in the State of Acre. The presence of T. cruzi-like and T. rangeli-like parasites are recorded in four new hosts.
    Keywords Trypanosoma cruzi ; Trypanosoma rangeli ; Trypanosoma minasense ; Trypanosoma devei ; Microbiology ; QR1-502 ; Science ; Q ; DOAJ:Microbiology ; DOAJ:Biology ; DOAJ:Biology and Life Sciences ; Arctic medicine. Tropical medicine ; RC955-962 ; Special situations and conditions ; RC952-1245 ; Internal medicine ; RC31-1245 ; Medicine ; R ; DOAJ:Internal medicine ; DOAJ:Medicine (General) ; DOAJ:Health Sciences
    Language English
    Publishing date 2000-04-01T00:00:00Z
    Publisher Instituto Oswaldo Cruz, Ministério da Saúde
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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