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 - 10 de 39
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    In vitro interaction of polyethylene glycol‐block‐poly (D,L‐lactide) nanocapsule devices with host cardiomyoblasts and trypanosoma cruzi‐infective forms.
    (2022) Siqueira, Raoni Pais; Milagre, Matheus Marques; Oliveira, Maria Alice de; Branquinho, Renata Tupinambá; Torchelsen, Fernanda Karoline Vieira da Silva; Lana, Marta de; Machado, Marina Guimarães Carvalho; Andrade, Margareth Spangler; Bahia, Maria Terezinha; Mosqueira, Vanessa Carla Furtado
    Chagas disease, caused by the protozoan Trypanosoma cruzi, is an important public health problem in Latin America. Nanoencapsulation of anti-T. cruzi drugs has signifcantly improved their efcacy and reduced cardiotoxicity. Thus, we investigated the in vitro interaction of polyethylene glycol-block-poly(D,L-lactide) nanocapsules (PEG-PLA) with trypomas- tigotes and with intracellular amastigotes of the Y strain in cardiomyoblasts, which are the infective forms of T. cruzi, using fuorescence and confocal microscopy. Fluorescently labeled nanocapsules (NCs) were internalized by non-infected H9c2 cells toward the perinuclear region. The NCs did not induce signifcant cytotoxicity in the H9c2 cells, even at the highest concentrations and interacted equally with infected and non-infected cells. In infected cardiomyocytes, NCs were distrib- uted in the cytoplasm and located near intracellular amastigote forms. PEG-PLA NCs and trypomastigote form interactions also occurred. Altogether, this study contributes to the development of engineered polymeric nanocarriers as a platform to encapsulate drugs and to improve their uptake by diferent intra- and extracellular forms of T. cruzi, paving the way to fnd new therapeutic strategies to fght the causative agent of Chagas disease.
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    The entrance route : oral, mucous, cutaneous, or systemic has a marked influence on the outcome of Trypanosoma cruzi experimental infection.
    (2022) Gonçalves, Karolina Ribeiro; Mazzeti, Ana Lia; Nascimento, Alvaro Fernando da Silva do; Lacerda, Jéssica Mara Castro; Paiva, Nívia Carolina Nogueira de; Mathias, Fernando Augusto Siqueira; Reis, Alexandre Barbosa; Caldas, Sérgio; Bahia, Maria Terezinha
    In recent decades, the oral infection of Trypanosoma cruzi has gathered increased attention due to frequent outbreaks that can lead to more severe clinical signs than those usually found in the areas of vector transmission. This study addresses the main routes of infection using metacyclic trypomastigotes (MT) and blood trypomastigotes (BT). Herein, BALB/c mice were infected with the Colombian (TcI) strain via intraperitoneal (IP), oral, intragastric (IG), ocular (OC) and cutaneous (CT) routes with 106 culture-derived MT or BT. Parasitemia was intermittent and low in animals inoculated with MT, in contrast, high parasitemia levels were found in BT-mice. A tropism for the muscles was observed in oral or IG infection with BT. Differently, the parasite was widely distributed in the tissues of mice infected with MT. However, the intensity of the inflammation infiltrating the tissues was higher in oral or IG infection with BT. Animals inoculated with BT via the IG route had similar serum levels of IFN-γ and smaller IL-10 compared to those infected with MT via the IG route. TNF-α levels were higher in the serum from BT-animals, which could explain the higher intensity of heart inflammation in these animals. Our results suggest that the infective form and the route of infection differentially modulated the outcome of Trypanosoma cruzi mice infection.
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    Review on experimental treatment strategies against Trypanosoma cruzi.
    (2021) Mazzeti, Ana Lia; Oliveira, Patricia Capelari de; Bahia, Maria Terezinha; Mosqueira, Vanessa Carla Furtado
    Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Currently, only nitroheterocyclic nifurtimox (NFX) and benznidazole (BNZ) are available for the treatment of Chagas disease, with limitations such as variable efficacy, long treatment regimens and toxicity. Different strategies have been used to dis cover new active molecules for the treatment of Chagas disease. Target-based and phenotypic screening led to thousands of compounds with anti-T. cruzi activity, notably the nitroheter ocyclic compounds, fexinidazole and its metabolites. In addition, drug repurposing, drug combinations, re-dosing regimens and the development of new formulations have been evaluated. The CYP51 antifungal azoles, as posaconazole, ravuconazole and its prodrug fosravuconazole presented promising results in experimental Chagas disease. Drug combina tions of nitroheterocyclic and azoles were able to induce cure in murine infection. New treatment schemes using BNZ showed efficacy in the experimental chronic stage, including against dormant forms of T. cruzi. And finally, sesquiterpene lactone formulated in nanocar riers displayed outstanding efficacy against different strains of T. cruzi, susceptible or resistant to BNZ, the reference drug. These pre-clinical results are encouraging and provide interesting evidence to improve the treatment of patients with Chagas disease.
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    Benznidazole self-emulsifying delivery system : a novel alternative dosage form for Chagas disease treatment.
    (2020) Mazzeti, Ana Lia; Oliveira, Liliam Teixeira; Gonçalves, Karolina Ribeiro; Schaun, Géssica C.; Mosqueira, Vanessa Carla Furtado; Bahia, Maria Terezinha
    Benznidazole (BZ) tablets are a unique form of treatment available for treating Chagas disease. Development of a liquid formulation containing BZ easy to administer orally for the treatment of paediatric patients, particularly for newborns is urgently required, with the same efficacy, safety and suitable biopharmaceutical properties as BZ tablets. Self-emulsifying drug delivery systems (SEDDS) may improve bioavailability of drugs such as BZ, which have poor water solubility and low permeability. In this context, the aim of this work was to develop a liquid BZ-SEDDS formulation as an alternative to tablets and to evaluate its cytotoxicity in different host cell lines and its efficacy in experimental Trypanosoma cruzi infection in mice. The optimized SEDDS formulation (25 mg/ml of BZ) induced no cytotoxicity in H9c2, HepG2 and Caco2 cells in vitro at 25 μM level. BZ-SEDDS and free-BZ showed similar in vitro trypanocidal activity in H9c2 cells infected by T. cruzi Y strain, with IC50 values of 2.10 ± 0.41 μM and 1.29 ± 0.01 μM for BZ and BZ-SEDDS, respectively. A follow up of efficacy in an acute model of infected mice resulted in the same percentage of cure (57%) for both free-BZ and BZ-SEDDS- groups according to established parameters. Furthermore, no additional in vivo toxicity was observed in animals treated with BZ-SEDDS. Taken together, in vitro and in vivo data of BZ-SEDDS showed that the incorporation of BZ into SEDDS does not alter its potency, efficacy and safety. Thus, BZ-SEDDS can be a more practical and personalized orally administered liquid dosage form compared to suspension of crushed BZ-tablets to treat newborn and young children by emulsifying SEDDS in different aqueous liquids with advantage of dosing flexibility.
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    Advances in Chagas disease chemotherapy.
    (2006) Guedes, Paulo Marcos da Matta; Fietto, Juliana Lopes Rangel; Lana, Marta de; Bahia, Maria Terezinha
    Chagas disease is endemic from Mexico to Argentina, where it is estimated that 16 to 18 million people are infected with its causative agent, Trypanosoma cruzi, and 100 million remain at risk of infection, emphasizing the necessity to sustain and extend control measures and strategies to combat this disease. Specific chemotherapy with benznidazole or nifurtimox has been recommended for treatment of recent and congenital infection. However, clinical trials with nifurtimox and benznidazole have shown that these compounds have very low activity in preventing the development of chronic Chagas disease. Moreover, the drugs induce a number of toxic side effects. The discovery of new active, non-toxic compounds would probably expand treatment, including those patients in which clinical manifestations are absent or can only be disclosed by more elaborate medical procedures. Recent developments in the study of basic biochemical aspects of T. cruzi have allowed for the identification of new targets for chemotherapy. Like many fungi, T. cruzi has a strict requirement for specific endogenous sterol synthesis for cell viability and growth and is extremely susceptible to sterol biosynthesis inhibitors (SBI). An intensive investigation of the potential trypanocidal effect of specific SBI has been performed, and it was demonstrated that some of these compounds exhibited suppressive and curative activity in murine and dog models of acute and chronic Chagas disease. Other potential targets for anti-T. cruzi chemotherapy that include the antiproliferative lysophospholipid analogs (evaluated in clinical trials as the first oral treatment for visceral leishmaniasis), cysteine protease inhibitors and compounds that interfere with purine salvage and inositol metabolism are also discussed.
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    Posttherapeutic cure criteria in Chagas disease : conventional serology followed by supplementary serological, parasitological, and molecular tests.
    (2012) Assis, Girley Francisco Machado de; Silva, Alexandre Rotondo da; Bem, Vitor Antônio Lemos do; Bahia, Maria Terezinha; Martins Filho, Olindo Assis; Dias, João Carlos Pinto; Viñas, Pedro Albajar; Torres, Rosália Morais; Lana, Marta de
    We performed a critical study of conventional serology, followed by supplementary serological, parasitological, and molecular tests, to assess the response to etiologic treatment of Chagas’ disease. A group of 94 Chagas’ disease patients treated with benznidazole at least 10 years earlier were evaluated from the laboratory and clinical points of view. When conventional serology (enzyme- linked immunosorbent assay [ELISA], indirect immunofluorescence [IIF], and indirect hemagglutination [IHA]) and classic criteria (consistent results with any two of the three tests) or more rigorous criteria (consistent results from the three tests) were used, 10.6% and 8.5% of patients were considered treated and cured (TC) by classic and rigorous criteria, respectively. Patients were then evaluated using supplementary (recombinant ELISA and Trypanosoma cruzi excreted-secreted antigen blotting [TESA-blot]), parasitological (hemoculture), and molecular (PCR) tests. The results of recombinant ELISA were similar to those with the rigorous criterion (three consistent test results). The TESA-blot group showed a higher percentage (21.3%) of negative results than the groups defined by either cure criterion. Hemoculture and PCR gave negative results for all treated and cured (TC) patients, regardless of the criterion used. Recombinant ELISA and TESA-blot tests showed negative results for 70% and 87.5% of the patients categorized as TC by the classic and three-test criteria, respectively. For patients with discordant conventional serology, the supplementary serological and molecular tests were the decisive factor in determining therapeutic failure. Clinical evaluation showed that 62.5% of TC patients presented with the indeterminate form of the disease. Additionally, treated patients with negative TESA-blot results should be reevaluated later with all methodologies used here to verify whether TESAblot is a reliable way to determine early parasitological cure of Chagas’ disease.
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    Activity of the new triazole derivative albaconazole against Trypanosoma (Schizotrypanum) cruzi in dog hosts.
    (2004) Guedes, Paulo Marcos da Matta; Urbina, Julio Alberto; Lana, Marta de; Afonso, Luís Carlos Crocco; Veloso, Vanja Maria; Tafuri, Washington Luiz; Coelho, George Luiz Lins Machado; Chiari, Egler; Bahia, Maria Terezinha
    Albaconazole is an experimental triazole derivative with potent and broad-spectrum antifungal activity and a remarkably long half-life in dogs, monkeys, and humans. In the present work, we investigated the in vivo activity of this compound against two strains of the protozoan parasite Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas’ disease, using dogs as hosts. The T. cruzi strains used in the study were previously characterized (murine model) as susceptible (strain Berenice-78) and partially resistant (strain Y) to the drugs currently in clinical use, nifurtimox and benznidazole. Our results demonstrated that albaconazole is very effective in suppressing the proliferation of the parasite and preventing the death of infected animals. Furthermore, the parasitological, PCR, serological, and proliferative assay results indicated parasitological cure indices of 25 and 100% among animals inoculated with T. cruzi strain Y when they were treated with albaconazole at 1.5 mg/kg of body weight/day for 60 and 90 days, respectively. On the other hand, although albaconazole given at 1.5 mg/kg/day was very effective in suppressing the proliferation of the parasite in animals infected with the Berenice-78 T. cruzi strain, no parasitological cure was observed among them, even when a longer treatment period (150 doses) was used. In conclusion, our results demonstrate that albaconazole has trypanocidal activity in vivo and is capable of inducing radical parasitological cure, although natural resistance to this compound was also indicated. Furthermore, the compound can be used in long-term treatment schemes (60 to 150 days) with minimal toxicity and thus represents a potentially useful candidate for the treatment of human Chagas’ disease.
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    Variation in susceptibility to benznidazole in isolates derived from Trypanosoma cruzi parental strains.
    (2001) Veloso, Vanja Maria; Toledo, Max Jean de Ornelas; Lana, Marta de; Chiari, Egler; Tafuri, Washington Luiz; Bahia, Maria Terezinha
    In this work, the susceptibility to benznidazole of two parental Trypanosoma cruzi strains, Colombian and Berenice-78, was compared to isolates obtained from dogs infected with these strains for several years. In order to evaluate the susceptibility to benznidazole two groups of mice were infected with one of five distinct populations isolated from dogs as well as the two parental strains of T. cruzi. The first group was treated with benznidazole during the acute phase and the second remained untreated controls. The animals were considered cured when parasitological and serological tests remained persistently negative. Mice infected with the Colombian strain and its isolates Colombian (A and B) did not cure after treatment. On the other hand, all animals infected with Berenice-78 were cured by benznidazole treatment. However, 100%, 50% and 70% of cure rates were observed in animals infected with the isolates Berenice-78 B, C and D, respectively. No significant differences were observed in serological profile of infected control groups, with all animals presenting high antibody levels. However, the ELISA test showed differences in serological patterns between mice inoculated with the different T. cruzi isolates and treated with benznidazole. This variability was dependent on the T. cruzi population used and seemed to be associated with the level of resistance to benznidazole.
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    Immunohistochemical studies in acute and chronic canine chagasic cardiomyopathy.
    (2002) Caliari, Marcelo Vidigal; Lana, Marta de; Cajá, Rosângela Aparecida França; Carneiro, Cláudia Martins; Bahia, Maria Terezinha; Santos, César Augusto Bueno dos; Magalhães, Gustavo Albergaria; Sampaio, Ivan Barbosa Machado; Tafuri, Washington Luiz
    A major characteristic of Chagas’ disease is a myocarditis constituted primarily of mononuclear cells, both during the acute and chronic phases of the disease. Using monoclonal antibodies and image analyses we have quantified canine CD8+ T cells (caCD8+ T cells), canine CD4+ T cells (caCD4+ T cells) and neutrophils in canine chagasic myocardiopathy induced by two strains isolated from the first human clinical case of Chagas’ disease. We also evaluated the influence of tissue parasitism in the genesis of chronic myocarditis through immunohistochemistry. As in human myocarditis, there was a predominance of T lymphocytes in the inflammatory infiltrate in all animals studied. In the dogs inoculated with strain Berenice 78 (Be78) and necropsied during the acute phase of infection, we found 58% caCD8+ and 42% caCD4+ T cells. In chronically infected animals, 53% of T cells were represented by caCD8+ and 47% were caCD4+ T cells. Since normal canine lymphoid organs are constituted by 70–80% caCD4+ T cells and 20–30% caCD8+ T cells our results indicate a higher proliferation of caCD8+ T cells in dogs inoculated with the Be78 strain. In chronic myocarditis induced by the Berenice 62 (Be62) strain, caCD8+ cells constituted 33% of the T cells and 67% were caCD4+ T cells, a proportion similar to that found in normal canine lymphoid organs. Since the Be78 strain induces greater loss of myocardiocytes than strain Be62, we believe that the caCD8+ T cells, among other factors, can be important in the genesis of these lesions. Amastigote nests and immunohistochemically labelled Trypanosoma cruzi antigen were not found in dogs necropsied during the chronic phase. The absence of the parasite in the myocardium suggests the involvement of other
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    Chemotherapy with Benznidazole and Itraconazole for mice infected with different Trypanosoma cruzi clonal genotypes.
    (2003) Toledo, Max Jean de Ornelas; Bahia, Maria Terezinha; Carneiro, Cláudia Martins; Martins Filho, Olindo Assis; Tibayrenc, Michel; Barnabé, Christian; Tafuri, Washington Luiz; Lana, Marta de
    The benznidazole (BZ) and itraconazole (ITC) susceptibilities of a standard set of Trypanosoma cruzi natural stocks were evaluated during the acute phase and the chronic phase of experimental chagasic infection in BALB/c mice. Twenty laboratory-cloned stocks representative of the total phylogenetic diversity of T. cruzi, including genotypes 20 and 19 (T. cruzi I) and genotypes 39 and 32 (T. cruzi II), were analyzed. Our results demonstrate important differences among stocks that could be pointed out as markers of biological behavior. Members of the T. cruzi I group were highly resistant to both BZ and ITC, whereas members of the T. cruzi II group were partially resistant to both drugs, despite their susceptibilities to ITC during the chronic phase of infection. The resistance to BZ observed for T. cruzi I was mainly triggered by genotype 20 isolates, whereas resistance to ITC was due to both genotype 20 and 19 isolates. Two polar patterns of response to BZ observed for genotype 39 isolates had a major impact on the partial resistance pattern observed for members of the T. cruzi II group. Genotype 32 isolates showed a typical profile of susceptibility. The correlation between the response to treatment and phylogenetic classification of T. cruzi stocks was clearer for ITC than for BZ. In conclusion, the data presented show a correlation between phylogenetic divergence among T. cruzi stocks and their susceptibilities to chemotherapeutic agents in vivo. Our results warn of the necessity to take into account the lesser genetic subdivisions of T. cruzi stocks since the upper subdivisions (T. cruzi I and II) show a great deal of heterogeneity for in vivo drug susceptibility.