Publications by authors named "Marina de Assis-Souza"

Visceral leishmaniasis caused by in Latin America progress with hepatosplenomegaly, pancytopenia, hypergammaglobulinemia, and weight loss and maybe lethal mainly in untreated cases. miRNAs are important regulators of immune and inflammatory gene expression, but their mechanisms of action and their relationship to pathogenesis in leishmaniasis are not well understood. In the present study, we sought to quantify changes in miRNAs associated with immune and inflammatory pathways using the promastigote infected- human monocytic THP-1 cell model and plasma from patients with visceral leishmaniasis.

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American Tegumentary Leishmaniasis (ATL) is an endemic disease in Latin America, mainly caused in Brazil by . Clinical manifestations vary from mild, localized cutaneous leishmaniasis (CL) to aggressive mucosal disease. The host immune response strongly determines the outcome of infection and pattern of disease.

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American Cutaneous leishmaniasis (ACL) is a public health problem. The immunological response is mainly dependent on T cell cytokine responses and might influence disease presentation, susceptibility and development. The understanding of the host immune response role in the control and in the pathology of leishmaniasis is relevant and has implications on diagnosis, follow-up and vaccine development.

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American tegumentary leishmaniasis (ATL) (also known as cutaneous leishmaniasis [CL]) is caused by various species of protozoa of the genus Leishmania The diagnosis is achieved on a clinical, epidemiological, and pathological basis, supported by positive parasitological exams and demonstration of leishmanin delayed-type hypersensitivity. Serological assays are not routinely used in the diagnosis because many are considered to have low sensitivity and the particular Leishmania species causing the disease can lead to variable performance. In the present study, we generated recombinant versions of two highly conserved Leishmania proteins, Leishmania (Viannia) braziliensis-derived Lb8E and Lb6H, and evaluated both in enzyme-linked immunosorbent assays (ELISA).

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Studies suggest the influence of immune response on the successful treatment of American tegumentary leishmaniasis (ATL), and indicate the existence of protective immunity in self-healed patients. Thus, the aim of this work was to quantify interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin (IL-) 10, IL-17, IL-22 and nitric oxide (NO) in culture supernatants of PBMC from patients with active disease (AD), after treatment (AT), and from self-healed (SH) and healthy subjects (CT), in response to Leishmania (Viannia) braziliensis insoluble antigen (AgIns). All groups of patients produced IFN-γ, indicating a predominant proinflammatory profile.

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American cutaneous leishmaniasis (ACL) is a disease where susceptibility or resistance is dependent on T cell response. This is characterized by an increased in CD4⁺ T cells, capable of inducing opposite disease profiles, and CD8⁺ T cells, that are related to immuno protection. We characterized T lymphocytes from patients before and after treatment, patients that spontaneously healed and controls, also evaluating their production of IL-10, IL-4, TNF-α and IFN-γ, after stimulation with soluble/insoluble antigenic fractions of Leishmania (Viannia) braziliensis.

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The aim of this study was to compare the techniques of indirect immunofluorescence assay (IFA) and flow cytometry to clinical and laboratorial evaluation of patients before and after clinical cure and to evaluate the applicability of flow cytometry in post-therapeutic monitoring of patients with American tegumentary leishmaniasis (ATL). Sera from 14 patients before treatment (BT), 13 patients 1 year after treatment (AT), 10 patients 2 and 5 years AT were evaluated. The results from flow cytometry were expressed as levels of IgG reactivity, based on the percentage of positive fluorescent parasites (PPFP).

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This study aims to investigate a flow cytometry performance-based methodology to detect anti-live (FC-ALPA-IgG) and anti-fixed (FC-AFPA-IgG) Leishmania (Viannia) braziliensis promastigote IgG as a means to monitor post-therapeutic cure of patients with localized cutaneous leishmaniasis (LCL). Serum samples from 30 LCL patients infected with L. (V.

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Although effective against epimastigotes (proliferative form) and of low cytotoxicity in mammals, the aryl-4-oxothiazolylhydrazones (ATZ) display only limited activity against trypomastigotes (bloodstream form) of Trypanosoma cruzi. Considering the metal complexation approach with bioactive ligands as one possible strategy for improving the biological efficacy of ATZ, a set of eight new ruthenium-ATZ complexes (RuCl(2)ATZCOD, COD is 1,5-cyclooctadiene) were prepared, chemically and biologically characterized, including in vitro assays against epimastigotes and trypomastigote forms of the parasite and also assessment of cytotoxicity in mammals. Two of these complexes presented antitrypanosomal activity at non-cytotoxic concentrations on mammalian cells and of higher potency than its metal-free ligands, while the metallic precursor [RuCl(2)COD(MeCN)(2)] showed only moderate antitrypanosomal activity.

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