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 88
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    Saliency-driven system models for cell analysis with deep learning.
    (2019) Ferreira, Daniel Silva; Ramalho, Geraldo Luis Bezerra; Torres, Débora; Tobias, Alessandra Hermógenes Gomes; Rezende, Mariana Trevisan; Medeiros, Fátima Nelsizeuma Sombra de; Bianchi, Andrea Gomes Campos; Carneiro, Cláudia Martins; Ushizima, Daniela Mayumi
    Background and objectives: Saliency refers to the visual perception quality that makes objects in a scene to stand out from others and attract attention. While computational saliency models can simulate the expert’s visual attention, there is little evidence about how these models perform when used to predict the cytopathologist’s eye fixations. Saliency models may be the key to instrumenting fast object detection on large Pap smear slides under real noisy conditions, artifacts, and cell occlusions. This paper describes how our computational schemes retrieve regions of interest (ROI) of clinical relevance using visual attention models. We also compare the performance of different computed saliency models as part of cell screening tasks, aiming to design a computer-aided diagnosis systems that supports cytopathologists. Method: We record eye fixation maps from cytopathologists at work, and compare with 13 different saliency prediction algorithms, including deep learning. We develop cell-specific convolutional neural networks (CNN) to investigate the impact of bottom-up and top-down factors on saliency prediction from real routine exams. By combining the eye tracking data from pathologists with computed saliency models, we assess algorithms reliability in identifying clinically relevant cells. Results: The proposed cell-specific CNN model outperforms all other saliency prediction methods, particularly regarding the number of false positives. Our algorithm also detects the most clinically relevant cells, which are among the three top salient regions, with accuracy above 98% for all diseases, except carcinoma (87%). Bottom-up methods performed satisfactorily, with saliency maps that enabled ROI detection above 75% for carcinoma and 86% for other pathologies. Conclusions: ROIs extraction using our saliency prediction methods enabled ranking the most relevant clinical areas within the image, a viable data reduction strategy to guide automatic analyses of Pap smear slides. Top-down factors for saliency prediction on cell images increases the accuracy of the estimated maps while bottom-up algorithms proved to be useful for predicting the cytopathologist’s eye fixations depending on parameters, such as the number of false positive and negative. Our contributions are: comparison among 13 state-of-the-art saliency models to cytopathologists’ visual attention and deliver a method that the associate the most conspicuous regions to clinically relevant cells.
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    Mayaro virus induction of oxidative stress is associated with liver pathology in a non-lethal mouse model.
    (2019) Caetano, Camila Carla da Silva; Camini, Fernanda Caetano; Almeida, Letícia Trindade; Ferraz, Ariane Coelho; Silva, Tales Fernando da; Lima, Rafaela Lameira Souza; Carvalho, Mayara Medeiros de Freitas; Castro, Thalles de Freitas; Carneiro, Cláudia Martins; Silva, Breno de Mello; Silva, Silvana de Queiroz; Magalhães, José Carlos de; Magalhães, Cíntia Lopes de Brito
    Mayaro virus (MAYV) causes Mayaro fever in humans, a self-limiting acute disease, with persistent arthralgia and arthritis. Although MAYV has a remerging potential, its pathogenic mechanisms remain unclear. Here, we characterized a model of MAYV infection in 3–4-week BALB/c mice. We investigated whether the liver acts as a site of viral replication and if the infection could cause histopathological alterations and an imbalance in redox homeostasis, culminating with oxidative stress. MAYV-infected mice revealed lower weight gain; however, the disease was self-resolving. High virus titre, neutralizing antibodies, and increased levels of aspartate and alanine aminotransferases were detected in the serum. Infectious viral particles were recovered in the liver of infected animals and the histological examination of liver tissues revealed significant increase in the inflammatory infiltrate. MAYV induced significant oxidative stress in the liver of infected animals, as well as a deregulation of enzymatic antioxidant components. Collectively, this is the first study to report that oxidative stress occurs in MAYV infection in vivo, and that it may be crucial in virus pathogenesis. Future studies are warranted to address the alternative therapeutic strategies for Mayaro fever, such as those based on antioxidant compounds.
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    Chemiluminescent ELISA with multi-epitope proteins to improve the diagnosis of canine visceral leishmaniasis.
    (2019) Fonseca, Thaisa Helena Silva; Faria, Angélica Rosa; Leite, Heloine Martins; Silveira, Júlia Angélica Gonçalves da; Carneiro, Cláudia Martins; Andrade, Hélida Monteiro de
    Diagnosing canine visceral leishmaniasis (CVL) is difficult because clinical signs of the disease are non-specific and a many infected animals in endemic areas, as in Brazil, are asymptomatic. Serological tests are the most common diagnostic methods employed, but most have limitations. For this reason, the implementation of a rapid, sensitive, and specific diagnostic test for CVL has become increasingly important. In this study, we adapted a chemiluminescent enzyme-linked immunosorbent assay (CL ELISA), using two multi-epitope recombinant proteins (PQ10 and PQ20) and a crude Leishmania antigen produced using promastigotes of L. infantum, as antigens to detect CVL infection in animals from Belo Horizonte. To investigate cross-reactions, samples from dogs with other infections (babesiosis, ehrlichiosis and Trypanosoma cruzi) were tested. Assay performance validations were conducted to analyse parameters such as variability, reproducibility, and stability. CL ELISA sensitivity/specificity with PQ10 antigen was 93.1%/80.0%; with the PQ20 protein 93.1%/96.6%; and with the crude antigen 75%/73.3%. Inter-assay variability and inter-operator coefficient of variation were <7% and <15%, with PQ10 and PQ20, respectively. The accuracy of the CL ELISA was classified as excellent for PQ10 (AUC = 0.95) and PQ20 (AUC = 0.98) and moderate for the crude antigen (AUC = 0.77). The kappa score for qualitative agreement between two plate lots was excellent for PQ10 (0.89) and good for PQ20 (0.65). PQ20 remained more stable than PQ10. The CL ELISA with recombinant proteins is a promising tool to diagnose CVL.
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    Effect on cellular recruitment and the innate immune response by combining saponin, monophosphoryl lipid-A and incomplete freund’s adjuvant with Leishmania (Viannia) braziliensis antigens for a vaccine formulation.
    (2019) Souza, Juliana Vitoriano de; Mathias, Fernando Augusto Siqueira; Moreira, Nádia das Dores; Soares, Rodrigo Dian de Oliveira Aguiar; Vieira, Paula Melo de Abreu; Carvalho, Andréa Teixeira de; Carneiro, Cláudia Martins; Giunchetti, Rodolfo Cordeiro; Brito, Rory Cristiane Fortes de; Fujiwara, Ricardo Toshio; Roatt, Bruno Mendes; Melo, Maria Norma; Reis, Alexandre Barbosa
    The poor immunogenicity displayed by some antigens has encouraged the development of strategies to improve the immune response and safety of vaccine candidates, resulting in an intense search for substances that potentiate vaccine response. Adjuvants have these properties helping vaccine candidates to induce a strong, durable, and fast immune response. In this study, we evaluated the specific immune response of adjuvants alone, Saponin (SAP), Incomplete Freund’s Adjuvant (IFA) and Monophosphoryl lipid-A SE (MPL-SE ) and in combination with total antigen of L. braziliensis (LB): LBSAP, LBIFA and LBMPL. The specific immune response induced by these compositions demonstrated that they were powerfully immunogenic, increasing cellular infiltration in the skin. Draining lymph nodes cultures showed that LBIFA and LBMPL have higher ability to increase the capacity of APCs to present antigens, with increased frequency of CD11c+ CD86+ cells. SAP, MPL, LBSAP, LBIFA and LBMPL could activate lymphocytes increasing expression of CD69 and CD25. LBSAP group was an excellent inducer of pro-inflammatory cytokines at 24 h. At 48 h, higher cytokines production was observed in IFA, LBIFA, MPL and LBMPL groups. Our data demonstrate that LBSAP and LBMPL are potential formulations to be tested in other experimental models. Also, the data obtained could expand the knowledge about immune response after sensitization and also contribute to the development of safe, immunogenic and effective vaccines.
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    Benznidazole, itraconazole and their combination in the treatment of acute experimental chagas disease in dogs.
    (2019) Cunha, Eleonora Lima Alves; Torchelsen, Fernanda Karoline Vieira da Silva; Cunha, Lucas Maciel; Oliveira, Maykon Tavares de; Fonseca, Kátia da Silva; Vieira, Paula Melo de Abreu; Carneiro, Cláudia Martins; Lana, Marta de
    Chagas disease (CD) is a serious public health problem in Latin America and its treatment remains neglected. Benznidazole (BZ), the only drug available in Brazil, presents serious side effects and low therapeutic efficacy, especially at the chronic phase. The last clinical trials demonstrated that the first generation of azole compounds were less successful than BZ in CD chemotherapy, which stimulated studies of these compounds associated to BZ and nifurtimox (NF). This study evaluated the therapeutic efficacy of BZ, itraconazole (ITZ) and their combination (BZ + ITZ) in dogs infected with the VL-10 T. cruzi strain in the acute phase of the disease. Twenty young mongrel dogs were inoculated with 2.0 × 103 blood trypomastigotes/kg and divided into four groups: treated with BZ, ITZ and BZ + ITZ for 60 days, and control group (INT). The parasitemia of the BZ + ITZ and BZ groups were similar and showed significant reduction compared to the INT group. The group treated with ITZ also showed significant parasitemia reduction compared to the INT group. The global analysis of hemoculture (HC), blood PCR, conventional serology (CS-ELISA), heart qPCR and histopathology techniques, used in the post-treatment evaluation, revealed that BZ + ITZ combination lead to a more reduction of parasitemia during the acute phase and heart qPCR positivity, less cardiac damage (inflammation and fibrosis in the left ventricle) and total survival. According to the classical cure criteria one animal treated with BZ + ITZ can be considered cured in its final evaluation and two other dogs, one of this group and one treated with ITZ were in process of cure. At least for BZ-resistant T. cruzi strains such as VL-10, BZ + ITZ was not effective to induce parasitological cure or a profound and sustained reduction of the parasite burden in blood and infected organs.
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    Radial feature descriptors for cell classification and recommendation.
    (2019) Silva, Romuere Rodrigues Veloso e; Araujo, Flavio Henrique Duarte de; Ushizima, Daniela Mayumi; Bianchi, Andrea Gomes Campos; Carneiro, Cláudia Martins; Medeiros, Fátima Nelsizeuma Sombra de
    This paper introduces computational tools for cell classification into normal and abnormal, as well as content-based-image-retrieval (CBIR) for cell recommendation. It also proposes the radial feature descriptors (RFD), which define evenly interspaced segments around the nucleus, and proportional to the convexity of the nuclear boundary. Experiments consider Herlev and CRIC image databases as input to classification via Random Forest and bootstrap; we compare 14 different feature sets by means of False Negative Rate (FNR) and Kappa (k), obtaining FNR = 0.02 and k = 0.89 for Herlev, and FNR = 0.14 and k = 0.78 for CRIC. Next, we sort and rank cell images using convolutional neural networks and evaluate performance with the Mean Average Precision (MAP), achieving MAP = 0.84 and MAP = 0.82 for Herlev and CRIC, respectively. Cell classification show encouraging results regarding RFD, including its sensitivity to intensity variation around the nuclear membrane as it bypasses cytoplasm segmentation.
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    Experimental steering of electron microscopy studies using prior X-ray computed tomography.
    (2019) Starborg, Tobias; O'Sullivan, James; Carneiro, Cláudia Martins; Behnsen, Julia; Else, Kathryn; Grencis, Richard; Withers, Philip John
    Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) can provide unrivalled high-resolution images of specific features and volumes of interest. However, the regions interrogated are typically very small, and sample preparation is both time-consuming and destructive. Here we consider how prior X-ray micro-computed tomography (microCT) presents an opportunity to increase the efficiency of electron microscopy in biology. We demonstrate how it can be used to; select the most promising samples and target site-specific locations; provide a wider context of the location being interrogated (multiscale correlative imaging); guide sample preparation and 3D imaging schemes; as well as quantify the effects of destructive sample preparation and staining procedures. We present a workflow utilising open source software in which microCT can be used either broadly, or precisely, to experimentally steer and inform subsequent electron microscopy studies. As automated sample registration procedures are developed to enable correlative microscopy, experimental steering by prior CT could be beneficially routinely incorporated into many experimental workflows.
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    Performance of recombinant chimeric proteins in the serological diagnosis of Trypanosoma cruzi infection in dogs.
    (2019) Leony, Leonardo Maia; Freitas, Natália Erdens Maron de; Del-Rei, Rodrigo Pimenta; Carneiro, Cláudia Martins; Reis, Alexandre Barbosa; Jansen, Ana Maria; Xavier, Samanta Cristina das Chagas; Gomes, Yara Miranda; Silva, Edimilson Domingos da; Reis, Mitermayer Galvão dos; Fraga, Deborah Bittencourt Mothé; Celedon, Paola Alejandra Fiorani; Zanchin, Nilson Ivo Tonin; Torres, Filipe Dantas; Santos, Fred Luciano Neves
    Background: Dogs are considered sentinels in areas of Trypanosoma cruzi transmission risk to humans. ELISA is generally the method of choice for diagnosing T. cruzi exposure in dogs, but its performance substantially depends on the antigenic matrix employed. In previous studies, our group has developed four chimeric antigens (IBMP-8.1, 8.2, 8.3, and 8.4) and evaluated their potential for diagnosing T. cruzi exposure in humans. For human sera, these chimeric antigens presented superior diagnostic performances as compared to commercial tests available in Brazil, Spain, and Argentina. Therefore, in this study we have evaluated the potential of these antigenic proteins for detection of anti-T. cruzi IgG antibodies in dog sera. Methodology/Principal findings: The IBMP-ELISA assays were optimized by checkerboard titration. Subsequently, the diagnostic potential was validated through analysis of ROC curves and the performance of the tests was determined using double entry tables. Cross-reactivity was also evaluated for babesiosis, ehrlichiosis, dirofilariosis, anaplasmosis, and visceral leishmaniasis. Best performance was shown by IBMP-8.3 and IBMP-8.4, although all four antigens demonstrated a high diagnostic performance with 46 positive and 149 negative samples tested. IBMP-8.3 demonstrated 100% sensitivity, followed by IBMP-8.4 (96.7–100%), IBMP-8.2 (73.3–87.5%), and IBMP-8.1 (50–100%). The highest specificities were achieved with IBMP-8.2 (100%) and IBMP-8.4 (100%), followed by IBMP-8.3 (96.7–97.5%) and IBMP 8.1 (89.1–100%). Conclusions/Significance: The use of chimeric antigenic matrices in immunoassays for anti-T. cruzi IgG antibody detection in sera of infected dogs was shown to be a promising tool for veterinary diagnosis and epidemiological studies. The chimeric antigens used in this work allowed also to overcome the common hurdles related to serodiagnosis of T. cruzi infection, especially regarding variation of efficiency parameters according to different strains and cross-reactivity with other infectious diseases.
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    Functionalized rifampicin-loaded nanostructured lipid carriers enhance macrophages uptake and antimycobacterial activity.
    (2019) Carneiro, Simone Pinto; Carvalho, Karen Vitor; Soares, Rodrigo Dian de Oliveira Aguiar; Carneiro, Cláudia Martins; Andrade, Milton Hércules Guerra de; Duarte, Rafael Silva; Santos, Orlando David Henrique dos
    Tuberculosis is an infectious bacterial disease that causes millions of deaths worldwide. Current treatment recommended by WHO is effective, however it is an extensive and arduous process associated to severe adverse effects, which induces a low patient compliance and the emerging of multidrug resistant tuberculosis. Thus, as a main goal of this study, rifampicin nanoparticles were surface functionalized with a tuftsin-modifed peptide to selectively recognize receptors located on infected alveolar macrophages, enhancing nanoparticles uptake by these cells and improving antimycobacterial activity. A tuftsin-based modified peptide was synthesized and successfully attached to nanoparticles interface (NP-pRIF). In parallel, nanoparticles without peptide were also developed for comparison (NP-RIF). Physicochemical characterization demonstrated that stable and monodisperse nanodelivery systems were obtained, with a controlled drug release profile and non-cytotoxic potential. Moreover, nanoparticles containing peptide were significantly more internalized by macrophages than nanoparticles without peptide over a wide range of time. Both nanoparticles were 2-fold more effective against M. tuberculosis than free rifampicin, suggesting NP-pRIF as a promising strategy for the management of tuberculosis treatment.
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    The schistosomiasis spleenOME : unveiling the proteomic landscape of splenomegaly using label-free mass spectrometry.
    (2019) Cosenza Contreras, Miguel de Jesus; Castro, Renata Alves de Oliveira e; Mattei, Bruno; Campos, Jonatan Marques; Silva, Gustavo Gonçalves; Paiva, Nívia Carolina Nogueira de; Soares, Rodrigo Dian de Oliveira Aguiar; Carneiro, Cláudia Martins; Afonso, Luís Carlos Crocco; Borges, William de Castro
    Schistosomiasis is a neglected parasitic disease that affects millions of people worldwide and is caused by helminth parasites from the genus Schistosoma. When caused by S. mansoni, it is associated with the development of a hepatosplenic disease caused by an intense immune response to the important antigenic contribution of adult worms and to the presence of eggs trapped in liver tissue. Although the importance of the spleen for the establishment of immune pathology is widely accepted, it has received little attention in terms of the molecular mechanisms operating in response to the infection. Here, we interrogated the spleen proteome using a label-free shotgun approach for the potential discovery of molecular mechanisms associated to the peak of the acute phase of inflammation and the development of splenomegaly in the murine model. Over fifteen hundred proteins were identified in both infected and control individuals and 325 of those proteins were differentially expressed. Two hundred and forty-two proteins were found upregulated in infected individuals while 83 were downregulated. Functional enrichment analyses for differentially expressed proteins showed that most of them were categorized within pathways of innate and adaptive immunity, DNA replication, vesicle transport and catabolic metabolism. There was an important contribution of granulocyte proteins and antigen processing and presentation pathways were augmented, with the increased expression of MHC class II molecules but the negative regulation of cysteine and serine proteases. Several proteins related to RNA processing were upregulated, including splicing factors. We also found indications of metabolic reprogramming in spleen cells with downregulation of proteins related to mitochondrial metabolism. Ex-vivo imunophenotyping of spleen cells allowed us to attribute the higher abundance of MHC II detected by mass spectrometry to increased number of macrophages (F4/80+/MHC II+ cells) in the infected condition. We believe these findings add novel insights for the understanding of the immune mechanisms associated with the establishment of schistosomiasis and the processes of immune modulation implied in the host-parasite interactions.