EFAR - Escola de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/451

Notícias

O curso de Farmácia em Ouro Preto foi criado em 1839, sendo a mais antiga Escola de Farmácia da América Latina.

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Resultados da Pesquisa

Agora exibindo 1 - 6 de 6
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    CD4+ T-lymphocytes from asymptomatic dogs infected with Leishmania infantum are able to activate macrophages for higher leishmanicidal ability in an in vitro co-culture experiment.
    (2022) Vieira, João Filipe Pereira; Cardoso, Jamille Mirelle de Oliveira; Brito, Rory Cristiane Fortes de; Roatt, Bruno Mendes; Carneiro, Cláudia Martins; Valadares, Diogo Garcia; Soares, Rodrigo Dian de Oliveira Aguiar; Reis, Alexandre Barbosa
    Dogs are the most common domestic reservoir of Leishmania infantum, making canine visceral leishmaniasis (CVL) a serious public health issue. Identifying new methodologies that can mimic lymphoid and myeloid competence in naturally infected dogs could lower costs and save time in preliminary screenings of potential immunotherapeutic agents and vaccines against CVL. For that, we established a cell-to-cell communication approach between lymphocytes and myeloid cells from healthy, asymptomatic (infected, without apparent clinical signs) and symptomatic (infected with apparent clinical signs) dogs. Peripheral blood mononuclear cells (PBMC) from these dogs were used as source of CD4+, CD8+ T lymphocytes and macrophages, that were posteriorly infected with L. infantum GFP+ promastigotes (green fluorescent protein). Macrophages co-cultured with purified lymphocytes were tested for the ability to control cellular parasitism, and their microbicidal function by producing nitric oxide (NO) and reactive oxygen species (ROS). The kind of T cell response within the co-culture was also evaluated, by assessing their ability to produce interferon-gamma (IFN-γ) and interleukin 4 (IL-4). The data suggests that T lymphocytes from symptomatic dogs are more prone to produce IL-4 than the ones from asymptomatic dogs. Macrophages from asymptomatic dogs also demonstrated a higher microbicidal potential, with increased levels of NO and ROS production, compared to symptomatic dogs, mainly in highly parasitized cells. Together, our results identify the ratio of IL-4/IFN-γ produced by CD4+ and CD8+ T cells, as well as, the ratio between parasite GFP signal/NO and ROS signal in macrophages as potential immunological biomarkers of failure and success of the screened agents. Our findings also propose a reliable methodology that can be used to follow the immune response in trials of potential drugs or vaccines targeting CVL.
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    Heterologous vaccine therapy associated with half course of Miltefosine promote activation of the proinflammatory response with control of splenic parasitism in a hamster model of visceral leishmaniasis.
    (2021) Carvalho, Lívia Mendes; Ferreira, Francielle Carvalho; Gusmão, Miriã Rodrigues; Costa, Ana Flávia Pereira; Brito, Rory Cristiane Fortes de; Soares, Rodrigo Dian de Oliveira Aguiar; Reis, Alexandre Barbosa; Cardoso, Jamille Mirelle de Oliveira; Carneiro, Cláudia Martins; Roatt, Bruno Mendes
    Visceral leishmaniasis (VL) is a serious and neglected disease present worldwide. Chemotherapy using pentavalent antimony (SbV) is the most practical and inexpensive strategy available for the VL treatment today, however, it has high toxicity. Alternatively, other drugs are used as viable leishmanicidal therapeutic options. Miltefosine is the only anti-leishmanial agent administered orally, however, it has been reducing its effectiveness. In this sense, there is no ideal therapy for VL since the drugs currently used trigger severe side effects causing discontinuation of treatment, which carries an imminent risk for the emergence of parasite resistance. With that, other therapeutic strategies are gaining prominence. Among them, immunotherapy and/or immunochemotherapy, which the activation/modulation of the immune system can redirect the host’s immune response to an effective therapeutic result. Therefore, this work was designed to assess an immunochemotherapy protocol composed of half course of Miltefosine associated with LBSap vaccine (Milt+LBSap) using the hamster Mesocricetus auratus as an experimental model for VL treatment. When evaluating the main hematobiochemical, immunological and therapeutic efficacy parameters, it was demonstrated that the treatment with Milt+LBSap showed restoration of hematobiochemical condition and reduced serum levels of IgG-anti-Leishmania compared to animals infected non treated (INT). Beyond that, an increase in the number of CD4+ lymphocytes producers of IFN-γ in relation to INT or to animals treated with miltefosine during 28 days, and TNF-α increased compared to INT were observed. Also, it was found a reduction of IL-10-production in relation to INT, or animals that received LBSap vaccine only, or miltefosine, following by a reduction in the splenic parasitic burden. These results demonstrate that the immunochemotherapy protocol used can stimulate the immune response, inducing an expressive cellular response sufficient to control spleen parasitism, standing out as a promising proposal for the VL treatment.
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    Immunotherapy and immunochemotherapy in visceral leishmaniasis : promising treatments for this neglected disease.
    (2014) Roatt, Bruno Mendes; Soares, Rodrigo Dian de Oliveira Aguiar; Vital, Wendel Coura; Ker, Henrique Gama; Moreira, Nádia das Dores; Souza, Juliana Vitoriano de; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; Reis, Alexandre Barbosa
    Leishmaniasis has several clinical forms: self-healing or chronic cutaneous leishmaniasis or post-kala-azar dermal leishmaniasis; mucosal leishmaniasis; visceral leishmaniasis (VL), which is fatal if left untreated.The epidemiology and clinical features of VL vary greatly due to the interaction of multiple factors including parasite strains, vectors, host genetics, and the environment. Human immunodeficiency virus infection augments the severity of VL increasing the risk of developing active disease by 100–2320 times. An effective vaccine for humans is not yet available. Resistance to chemotherapy is a growing problem in many regions, and the costs associated with drug identification and development, make commercial production for leishmaniasis, unattractive.The toxicity of currently drugs, their long treatment course, and limited efficacy are significant concerns. For cutaneous disease, many studies have shown promising results with immunotherapy/immunochemotherapy, aimed to modulate and activate the immune response to obtain a therapeutic cure. Nowadays, the focus of many groups centers on treating canine VL by using vaccines and immunomodulators with or without chemotherapy. In human disease, the use of cytokines like interferon-g associated with pentavalent antimonials demonstrated promising results in patients that did not respond to conventional treatment. In mice, immunomodulation based on monoclonal antibodies to remove endogenous immunosuppressive cytokines (interleukin-10) or block their receptors, antigen-pulsed syngeneic dendritic cells, or biological products like Pam3Cys (TLR ligand) has already been shown as a prospective treatment of the disease. This review addresses VL treatment, particularly immunotherapy and/or immunochemotherapy as an alternative to conventional drug treatment in experimental models, canine VL, and human disease.
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    Clinical, hematological and biochemical alterations in hamster (Mesocricetus auratus) experimentally infected with Leishmania infantum through different routes of inoculation.
    (2016) Moreira, Nádia das Dores; Souza, Juliana Vitoriano de; Roatt, Bruno Mendes; Vieira, Paula Melo de Abreu; Vital, Wendel Coura; Cardoso, Jamille Mirelle de Oliveira; Rezende, Mariana Trevisan; Ker, Henrique Gama; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; Reis, Alexandre Barbosa
    Background: Leishmaniasis remains among the most important parasitic diseases in the developing world and visceral leishmaniasis (VL) is the most fatal. The hamster Mesocricetus auratus is a susceptible model for the characterization of the disease, since infection of hamsters with L. infantum reproduces the clinical and pathological features of human VL. In this context, it provides a unique opportunity to study VL in its active form. The main goal of this study was to evaluate the clinical, biochemical, and hematological changes in male hamsters infected through different routes and strains of L. infantum. Methods: In the current study, hamsters (Mesocricetus auratus) were infected with the L. infantum strains (WHO/MHOM/BR/74/PP75 and MCAN/BR/2008/OP46) by intradermal, intraperitoneal and intracardiac routes. The animals were monitored for a nine month follow-up period. Results: The hamsters showed clinical signs similar to those observed in classical canine and human symptomatic VL, including splenomegaly, severe weight loss, anemia, and leucopenia. Therefore the OP46 strain was more infective, clinical signs were more frequent and more exacerbated in IC group with 80 to 100 % of the animals showing splenomegaly, in the last month infection. Additionally, desquamation, hair loss and external mucocutaneous lesions and ulcers localized in the snout, accompanied by swelling of the paws in all animals, were observed. Consequently, the animals presented severe weight loss/cachexia, hunched posture, an inability to eat or drink, and non-responsiveness to external stimuli. Furthermore, regardless of strain, route of inoculum and time assessed, the animals showed renal and hepatic alterations, with increased serum levels of urea and creatinine as well as elevated serum levels of aspartate aminotransferase and alanine aminotransferase. Conclusions: These results strongly suggest that the inoculation through the intracardiac route resulted in a higher severity among infections, especially in the sixth and ninth month after infection via intracardiac, exhibited clinical manifestations and biochemical/hematological findings similar to human visceral leishmaniasis. Therefore, we suggest that this route must be preferentially used in experimental infections for pathogenesis studies of VL in the hamster model.
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    Molecular diagnosis of canine visceral leishmaniasis : a comparative study of three methods using skin and spleen from dogs with natural Leishmania infantum infection.
    (2013) Reis, Levi Eduardo Soares; Vital, Wendel Coura; Roatt, Bruno Mendes; Bouillet, Leoneide Érica Maduro; Ker, Henrique Gama; Brito, Rory Cristiane Fortes de; Resende, Daniela de Melo; Carneiro, Cláudia Martins; Reis, Alexandre Barbosa
    Polymerase chain reaction (PCR) and its variations represent highly sensitive and specificmethods for Leishmania DNA detection and subsequent canine visceral leishmaniasis (CVL)diagnosis. The aim of this work was to compare three different molecular diagnosis tech-niques (conventional PCR [cPCR], seminested PCR [snPCR], and quantitative PCR [qPCR])in samples of skin and spleen from 60 seropositive dogs by immunofluorescence antibodytest and enzyme-linked immunosorbent assay. Parasitological analysis was conducted byculture of bone marrow aspirate and optical microscopic assessment of ear skin and spleensamples stained with Giemsa, the standard tests for CVL diagnosis. The primers L150/L152and LINR4/LIN17/LIN19 were used to amplify the conserved region of the Leishmania kDNAminicircle in the cPCR, and snPCR and qPCR were performed using the DNA polymerasegene (DNA pol _) primers from Leishmania infantum. The parasitological analysis revealedparasites in 61.7% of the samples. Sensitivities were 89.2%, 86.5%, and 97.3% in the skin and81.1%, 94.6%, and 100.0% in spleen samples used for cPCR, snPCR, and qPCR, respectively.We demonstrated that the qPCR method was the best technique to detect L. infantum inboth skin and spleen samples. However, we recommend the use of skin due to the highsensitivity and sampling being less invasive.
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    Clinical forms of canine visceral Leishmaniasis in naturally Leishmania infantum – infected dogs and related myelogram and hemogram changes.
    (2013) Nicolato, Roney Luiz de Carvalho; Abreu, Raquel Trópia de; Roatt, Bruno Mendes; Soares, Rodrigo Dian de Oliveira Aguiar; Reis, Levi Eduardo Soares; Carvalho, Maria das Graças; Carneiro, Cláudia Martins; Giunchetti, Rodolfo Cordeiro; Bouillet, Leoneide Érica Maduro; Lemos, Denise da Silveira; Vital, Wendel Coura; Reis, Alexandre Barbosa
    Hematological analysis has limited applications for disease diagnosis in Leishmania infantum–infected dogs, but it can be very important in evaluating the clinical forms of the disease and in understanding the evolution of canine visceral leishmaniasis (CVL) pathogenesis. Recently, we demonstrated that alterations in leucopoiesis and erythropoiesis are related to clinical status and bone marrow parasite density in dogs naturally infected by L. infantum. To further characterize these alterations, we evaluated the association between the hematological parameters in bone marrow and peripheral blood alterations in groups of L. infantum–infected dogs: asymptomatic I (AD-I: serum negative/PCR+), asymptomatic II (AD-II: serum positive), oligosymptomatic (OD), and symptomatic (SD). Results were compared with those from noninfected dogs (NID). The SD group was found to present a decrease in erythropoietic lineage with concomitant reductions in erythrocytes, hemoglobin, and hematocrit parameters, resulting in anemia. The SD group also had increased neutrophils and precursors and decreased band eosinophils and eosinophils, leading to peripheral blood leucopenia. In the AD-II group, lymphocytosis occurred in both the peripheral blood and the bone marrow compartments. The SD group exhibited lymphocytosis in the bone marrow, with lymphopenia in the peripheral blood. In contrast, the AD-I group, showed no significant changes suggestive of CVL, presenting normal counts in bone marrow and peripheral blood. Our results showed for the first time that important changes in hematopoiesis and hematological parameters occur during ongoing CVL in naturally infected dogs, mainly in symptomatic disease. Taken together, our results based on myelogram and hemogram parameters enable better understanding of the pathogenesis of the anemia, lymphocytosis, and lymphopenia, as well as the leucopenia (eosinopenia and monocytopenia), that contribute to CVL prognosis.