[Show abstract][Hide abstract] ABSTRACT: Antiretroviral therapy has been associated with side effects, either from the drug itself or in conjunction with the effects of human immunodeficiency virus infection. Here, we evaluated the side effects of the protease inhibitor (PI) indinavir in hamsters consuming a normal or high-fat diet. Indinavir treatment increased the hamster death rate and resulted in an increase in triglyceride, cholesterol and glucose serum levels and a reduction in anti-oxLDL auto-antibodies. The treatment led to histopathological alterations of the kidney and the heart. These results suggest that hamsters are an interesting model for the study of the side effects of antiretroviral drugs, such as PIs.
Memórias do Instituto Oswaldo Cruz 07/2014; 109(4):484-7. · 1.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Routine serological diagnoses for leishmaniasis, except in visceral cases, are performed using whole-parasite antigens. We used enzyme-linked immunosorbent assay (ELISA) to evaluate the performance of Leishmania infantum rHsp83 compared with L. major-like total promastigote antigen in the diagnosis of cutaneous (CL), mucosal (ML), and visceral leishmaniasis (VL). ELISA-rHsp83 was significantly more sensitive than ELISA-L. major-like when considering either CL/ML (P = 0.041) or all leishmaniasis patients (P = 0.013). When samples from other infectious disease patients were evaluated for cross-reactivity, ELISA-rHsp83 was more specific than ELISA-L. major-like, specifically for Chagas disease samples (P < 0.001). We also evaluated the anti-rHsp83 antibody titers months after treatment and observed no significant difference in ML (P = 0.607) or CL (P = 0.205). We recommend ELISA-L. infantum-rHsp83 as a routine confirmatory serological assay for the diagnosis of Leishmania infection because of the high sensitivity, the specificity, and the insignificant cross-reactivity with other infectious diseases.
The American journal of tropical medicine and hygiene 03/2014; · 2.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Previously, we showed in Leishmania infections that extrinsic insulin-like growth factor (IGF)-I favored Leishmania proliferation and leishmaniasis development. In this study, the interaction of intrinsically expressed IGF-I and Leishmania (Leishmania) major in macrophages was addressed, and a key finding was the observation, using confocal microscopy, of the co-localization of IGF-I and parasites within macrophages. Following stimulation with interferon-γ (IFN-γ), which is known to inhibit IGF-I production in macrophages, we observed a reduction in the expression of both IGF-I RNA and protein. This reduced expression was accompanied by a reduction in the cellular parasite load that was completely recovered with the addition of extrinsic IGF-I, which suggests an essential role for IGF-I in Leishmania growth. Key-words: Insulin-like growth factor I, Leishmania (Leishmania) major, macrophage, confocal microscopy, Interferon-γ. This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Amino-functionalized luminescent silica particles were investigated for use in immunoassays. The particles were prepared by the Stöber method where the [Eu(TTA)3(H2O)2] complex (TTA: 3-thenoyltrifluoroacetonate) was incorporated into silica particles during the hydrolysis and condensation of TEOS: tetraethylorthosilicate. Then, the amino groups were introduced in the particle surface using APTS: 3-aminopropyltriethoxisilane. The resulting particles were characterized by scanning electron microscopy (SEM), X ray diffraction (XRD) and photoluminescence spectroscopy. In order to demonstrate the viability of the use of luminescent particles as optical markers, an enzyme-substrate reaction was performed using HRP: horseradish peroxidase. It was possible to verify the binding of HRP-oxidized LDL (low density lipoprotein) and anti-oxLDL antibody-luminescent silica particles through the evaluation of the presence of HRP. The bioassay data open a broad field for the development of protein-tagged luminescent particles for use in biomedical sciences.
Journal of inorganic biochemistry 02/2013; 123C:11-17. · 3.25 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Visceral leishmaniasis (VL) caused in the New World by Leishmania (Leishmania) infantum chagasi has dog as important peridomestic reservoir in its transmission cycle. Since VL in infected animals is similar to human VL, its study is interesting for human pathology. During Leishmania infection, insulin-like growth factor-I (IGF-I) plays a role in the host-parasite interaction, favoring parasite growth, particularly acting directly on Leishmania. We evaluated IGF-I mRNA expression in different organs/tissues, which was differently modulated in dogs naturally infected by L. (L.) infantum chagasi. We also evaluated the hepatic IGF-I mRNA and serum IGF-I levels in infected dogs. Hepatic mRNA IGF-I expression was higher in the infected dogs than in control animals. However, the serum levels of IGF-I, which are related to the production of this factor in the liver, were reduced in the infected dogs compared with the non-infected controls. Thus, we suggest interference in post-transcriptional processing in IGF-I production in active visceral leishmaniasis.
Veterinary Immunology and Immunopathology 11/2012; · 1.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Malaria in Brazil is endemic in the Amazon region, but autochthonous cases with low parasitaemia occur in the Atlantic Forest area of the country. According to Brazilian legislation no test is mandatory for blood donors from non-endemic areas. However if they have traveled to malaria transmission regions they are deferred for six months before they can donate. This report describes a transfusion-transmitted malaria case in Sao Paulo, Brazil, where one recipient received infected blood and developed the disease. He lived in Sao Paulo and had no previous transfusion or trips to endemic areas, including those of low endemicity, such as Atlantic Forest. Thick blood smears confirmed Plasmodium malariae. All donors lived in Sao Paulo and one of them (Donor 045-0) showed positive hemoscopy and PCR. This asymptomatic donor had traveled to Juquia, in the Atlantic Forest area of S ao Paulo State, where sporadic cases of autochthonous malaria are described. DNA assay revealed P. malariae in the donor's (Donor 045-0) blood. Serum archives of the recipient and of all blood donors were analyzed by ELISA using both P. vivax and P. falciparum antigens, and IFAT with P. malariae. Donor 045-0's serum was P. malariae IFAT positive and the P. vivax ELISA was reactive. In addition, two out of 44 donors' archive sera were also P. vivax ELISA reactive. All sera were P. falciparum ELISA negative. This case suggests the need of reviewing donor selection criteria and deferral strategies to prevent possible cases of transfusion-transmitted malaria.
Revista do Instituto de Medicina Tropical de São Paulo 02/2011; 53(1):55-9. · 0.96 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We analyzed the impact of chronic exposure to urban air pollution on the development of atherosclerosis. Hyperlipemic mice (LDLR(-/-)) were submitted to a high fat diet and air pollution for four months. We measured the susceptibility of LDL to oxidative modifications (TBARS), the presence of anti-oxLDL and an apoB-derived peptide (apoB-D) in blood and the degree of atherosclerosis in the aortic arch. Air pollution increased the susceptibility of LDL to oxidation as well as anti-oxLDL and anti-apo-B levels. These levels were even higher than in mice submitted to a high fat diet and non-polluted air. The lipid content of the atherosclerotic plaques in the aorta was increased in groups with a high cholesterol diet independently of the air quality. However, the thickness of the arterial wall was greater in mice fed a high lipid diet with polluted air. Thus, we conclude that urban air pollution exacerbates the susceptibility of LDL to oxidation, atherogenesis and vascular remodeling in hyperlipemic mice and that an immune response accompanies this process.