DEFAR - Artigos publicados em periódicos

URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531

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    Rapid antigen test as a tool for the identification of SARS-CoV-2 infection and its potential as a self-testing device.
    (2023) Filgueiras, Priscilla Soares; Corsini, Camila Amormino; Almeida, Nathalie Bonatti Franco; Pedrosa, Maria Luysa Camargos; Miranda, Daniel Alvim Pena de; Gomes, Sarah Vieira Contin; Assis, Jéssica Vieira de; Silva, Raphael Antônio; Medeiros, Maria Izabella Vieira de Assis Rocha Carvalho de; Lourenço, Adelina Junia; Bicalho, Cecilia Maria Florencio; Vilela, Raquel Virgínia Rocha; Jeremias, Wander de Jesus; Fernandes, Gabriel da Rocha; Grenfell, Rafaella Fortini Queiroz
    Background: SARS-CoV-2 virus originated in Wuhan (China) in December (2019) and quickly spread worldwide. Antigen tests are rapid diagnostic tests (RDT) that produce results in 15-30 min and are an important tool for the scale-up of COVID-19 testing. COVID-19 diagnostic tests are authorized for self-testing at home in some countries, including Brazil. Widespread COVID-19 diagnostic testing is required to guide public health policies and control the speed of transmission and economic recovery. Methods: Patients with suspected COVID-19 were recruited at the Hospital da Baleia (Belo Horizonte, Brazil). The SARS-CoV-2 antigen- detecting rapid diagnostic tests were evaluated from June 2020 to June 2021 using saliva, nasal, and nasopharyngeal swab samples from 609 patients. Patient samples were simultaneously tested using a molecular assay (RT-qPCR). Sensitivity, specificity, accuracy, and positive and negative predictive values were determined using the statistical program, MedCalc, and GraphPad Prism 8.0. Results: The antigen-detecting rapid diagnostic tests displayed 98% specificity, 60% sensitivity, 96% positive predictive value, and moderate concordance with RT-qPCR. Substantial agreement was found between the two methods for patients tested < 7 days of symptom onset. Conclusions: Our findings support the use of Ag-RDT as a valuable and safe diagnostic method. Ag-RDT was also demonstrated to be an important triage tool for suspected COVID-19 patients in emergencies. Overall, Ag-RDT is an effective strategy for reducing the spread of SARS-CoV-2 and contributing to COVID-19 control.
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    Immunogenicity, effectiveness, and safety of inactivated virus (CoronaVac) vaccine in a two-dose primary protocol and BNT162b2 heterologous booster in Brazil (Immunita-001) : a one year period follow up phase 4 study.
    (2022) Grenfell, Rafaella Fortini Queiroz; Almeida, Nathalie Bonatti Franco; Filgueiras, Priscilla Soares; Corsini, Camila Amormino; Gomes, Sarah Vieira Contin; Miranda, Daniel Alvim Pena de; Lourenço, Adelina Junia; Martins Filho, Olindo Assis; Oliveira, Jaquelline Germano de; Carvalho, Andréa Teixeira de; Campos, Guilherme Rodrigues Fernandes; Nogueira, Maurício Lacerda; Alves, Pedro Augusto; Fernandes, Gabriel da Rocha; Castilho, Leda dos Reis; Lima, Túlio Macedo; Abreu, Daniel Paiva Barros de; Alvim, Renata Guimarães Ferreira; Silva, Thaís Bárbara de Souza; Jeremias, Wander de Jesus; Otta, Dayane Andriotti; Azevedo, Ana Carolina Campi; Immunita-001 Team
    Background: Effective and safe vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical to controlling the COVID-19 pandemic and will remain the most important tool in limiting the spread of the virus long after the pandemic is over. Methods: We bring pioneering contributions on the maintenance of the immune response over a year on a real-life basis study in 1,587 individuals (18-90 yrs, median 39 yrs; 1,208 female/379 male) who underwent vaccination with two doses of CoronaVac and BNT162b2 booster after 6-months of primary protocol. Findings: Elevated levels of anti-spike IgG antibodies were detected after CoronaVac vaccination, which significantly decreased after 80 days and remained stable until the introduction of the booster dose. Heterologous booster restored antibody titers up to-1·7- fold, changing overall seropositivity to 96%. Titers of neutralising antibodies to the Omicron variant were lower in all timepoints than those against Delta variant. Individuals presenting neutralising antibodies against Omicron also presented the highest titers against Delta and anti-Spike IgG. Cellular immune response measurement pointed out a mixed immune profile with a robust release of chemokines, cytokines, and growth factors on the first month after CoronaVac vaccination followed by a gradual reduction over time and no increase after the booster dose. A stronger interaction between those mediators was noted over time. Prior exposure to the virus leaded to a more robust cellular immune response and a rise in antibody levels 60 days post CoronaVac than in individuals with no previous COVID-19. Both vaccines were safe and well tolerated among individuals. Interpretation: Our data approach the effectiveness of CoronaVac association with BNT162b2 from the clinical and biological perspectives, aspects that have important implications for informing decisions about vaccine boosters. Funding: Fiocruz, Brazil.
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    Tetraspanin co029 expression as a tumor biomarker for monoclonal antibodies preparation : antigenic assessment in colorectal cancer cells.
    (2022) Coutinho, Lucelia; Corsini, Camila Amormino; Assis, Jéssica Vieira de; Pedrosa, Maria Luysa; Jeremias, Wander de Jesus; Santos, Viviane; Cabral, Mônica Maria Demas Álvares; Mesquita, Ana Sofia; Viviani, Matheus; Rodrigues, Angelica Nogueira; Grenfell, Rafaella Fortini Queiroz
    Introduction: The identification of innovative cancer biomarkers is a very relevant ongoing quest. Moreover, their role in cancer diagnosis and clinical management has been radically changed in the last few years with the major emphasis on cancer molecular classification, therapeutic target identification, and therapeutic protocol responsivity. tetraspanins are a family of transmembrane proteins correlated with tumor stage, tumor type and patient out- come affecting cell growth, morphology, invasion, and metastasis. Methods: We expressed the 31kDa transmembrane human tetraspanin co029 antigen in Escherichia coli expression host cells using Gateway® platform. Western blotting and ELISA techniques, together with gene sequencing, confirmed the identity of TSP co029 recombinant protein. Forty clones producing antibodies against TSP co029 were obtained. These antibodies were incubated with human colorectal cancer cells in different conditions. ELISA and immunohistochemistry were also performed. Results: The expressed tetraspanin had an appropriate conformation and antigenic integrity to produce antibodies with affinity to the native TSP co029 biomarker. The affinity of the purified recombinant protein and antibodies were confirmed by western blotting, florescent staining of human colorectal cancer cells in fluorescence and confocal microscopies and by ELISA and immunohistochemistry. Conclusion: Our data showed that the recombinant protein and antibodies produced in this study allowed the confirmation of tetraspanin co029 protein presented on the surface of human colorectal cancer cells.
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    Deep sequencing of small RNAs reveals the repertoire of miRNAs and piRNAs in Biomphalaria glabrata.
    (2020) Queiroz, Fábio Ribeiro; Portilho, Laysa Gomes; Jeremias, Wander de Jesus; Babá, Élio Hideo; Amaral, Laurence Rodrigues do; Silva, Luciana Maria; Coelho, Paulo Marcos Zech; Caldeira, Roberta Lima; Gomes, Matheus de Souza
    BACKGROUND Biomphalaria glabrata snails are widely distributed in schistosomiasis endemic areas like America and Caribe, displaying high susceptibility to infection by Schistosoma mansoni. After the availability of B. glabrata genome and transcriptome data, studies focusing on genetic markers and small non-coding RNAs have become more relevant. The small RNAs have been considered important through their ability to finely regulate the gene expression in several organisms, thus controlling the functions like cell growth, metabolism, and susceptibility/resistance to infection. OBJECTIVE The present study aims on identification and characterisation of the repertoire of small non-coding RNAs in B. glabrata (Bgl-small RNAs). METHODS By using small RNA sequencing, bioinformatics tools and quantitative reverse transcription polymerase chain reaction (RT-qPCR), we identified, characterised, and validated the presence of small RNAs in B. glabrata. FINDINGS 89 mature miRNAs were identified and five of them were classified as Mollusk-specific. When compared to model organisms, sequences of B. glabrata miRNAs showed a high degree of conservation. In addition, several target genes were predicted for all the mature miRNAs identified. Furthermore, piRNAs were identified in the genome of B. glabrata for the first time. The B. glabrata piRNAs showed strong conservation of uridine as first nucleotide at 5’ end, besides adenine at 10th position. Our results showed that B. glabrata has diverse repertoire of circulating ncRNAs, several which might be involved in mollusk susceptibility to infection, due to their potential roles in the regulation of S. mansoni development. MAIN CONCLUSIONS Further studies are necessary in order to confirm the role of the Bgl-small RNAs in the parasite/host relationship thus opening new perspectives on interference of small RNAs in the organism development and susceptibility to infection.
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    Schistosomiasis in Nigeria : gleaning from the past to improve current efforts towards control.
    (2020) Oyeyemi, Oyetunde Timothy; Jeremias, Wander de Jesus; Grenfell, Rafaella Fortini Queiroz
    The effort to control schistosomiasis in Nigeria has been scaled up the past few years. Schistosomiasis affects all age groups, however, school children are at the highest risk of the disease. In the past years, global partners in schistosomiasis control have renewed their commitments. Many countries including few in Africa are working towards eliminating the disease. In Nigeria, the transmission of schistosomiasis is still active. This poses a serious health challenge as morbidity builds up in infected individuals. Mass drug administration (MDA) has helped to reduce morbidity but it is not adequate to abate transmission in many areas of the country. The integration of other aspects of control will provide a more sustainable result. This review attempted to discuss schistosomiasis transmission patterns in Nigeria in different eras. We identified some pitfalls in efforts towards the control of schistosomiasis in Nigeria. We recommended research priority in areas of neglect and advocated for integrated control.
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    Serological proteomic screening and evaluation of a recombinant egg antigen for the diagnosis of low-intensity Schistosoma mansoni infections in endemic area in Brazil.
    (2019) Moraes, Vanessa Silva; Shollenberger, Lisa Marie; Borges, William de Castro; Rabello, Ana Lucia Teles; Harn, Donald A.; Medeiros, Lia Carolina Soares; Jeremias, Wander de Jesus; Siqueira, Liliane Maria Vidal; Pereira, Caroline Stephane Salviano; Pedrosa, Maria Luysa Camargos; Almeida, Nathalie Bonatti Franco; Almeida, Aureo; Lambertucci, Jose Roberto; Carneiro, Nídia Francisca de Figueiredo; Coelho, Paulo Marcos Zech; Grenfell, Rafaella Fortini Queiroz
    Background Despite decades of use of control programs, schistosomiasis remains a global public health problem. To further reduce prevalence and intensity of infection, or to achieve the goal of elimination in low-endemic areas, there needs to be better diagnostic tools to detect low- intensity infections in low-endemic areas in Brazil. The rationale for development of new diagnostic tools is that the current standard test Kato-Katz (KK) is not sensitive enough to detect low-intensity infections in low-endemic areas. In order to develop new diagnostic tools, we employed a proteomics approach to identify biomarkers associated with schisto- some-specific immune responses in hopes of developing sensitive and specific new meth- ods for immunodiagnosis. Methods and findings Immunoproteomic analyses were performed on egg extracts of Schistosoma mansoni using pooled sera from infected or non-infected individuals from a low-endemic area of Brazil. Cross reactivity with other soil-transmitted helminths (STH) was determined using pooled sera from individuals uniquely infected with different helminths. Using this approach, we identified 23 targets recognized by schistosome acute and chronic sera samples. To identify immunoreactive targets that were likely glycan epitopes, we compared these targets to the immunoreactivity of spots treated with sodium metaperiodate oxidation of egg extract. This treatment yielded 12/23 spots maintaining immunoreactivity, suggesting that they were protein epitopes. From these 12 spots, 11 spots cross-reacted with sera from individuals infected with other STH and 10 spots cross-reacted with the negative control group. Spot number 5 was exclusively immunoreactive with sera from S. mansoni-infected groups in native and deglycosylated conditions and corresponds to Major Egg Antigen (MEA). We expressed MEA as a recombinant protein and showed a similar recognition pattern to that of the native protein via western blot. IgG-ELISA gave a sensitivity of 87.10% and specificity of 89.09% represented by area under the ROC curve of 0.95. IgG-ELISA performed better than the conventional KK (2 slides), identifying 56/64 cases harboring 1–10 eggs per gram of feces that were undiagnosed by KK parasitological technique. Conclusions The serological proteome approach was able to identify a new diagnostic candidate. The recombinant egg antigen provided good performance in IgG-ELISA to detect individuals with extreme low-intensity infections (1 egg per gram of feces). Therefore, the IgG-ELISA using this newly identified recombinant MEA can be a useful tool combined with other techniques in low-endemic areas to determine the true prevalence of schistosome infection that is underestimated by the KK method. Further, to overcome the complexity of ELISA in the field, a second generation of antibody-based rapid diagnostic tests (RDT) can be developed.
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    Genome-wide identification, characterisation and expression profiling of the ubiquitin-proteasome genes in Biomphalaria glabrata.
    (2019) Portilho, Laysa Gomes; Duarte, Bruna Custódio Dias; Queiroz, Fábio Ribeiro; Ribeiro, Thales Henrique Cherubino; Jeremias, Wander de Jesus; Babá, Élio Hideo; Coelho, Paulo Marcos Zech; Morais, Enyara Rezende; Cabral, Fernanda Janku; Caldeira, Roberta Lima; Gomes, Matheus de Souza
    BACKGROUND Biomphalaria glabrata is the major species used for the study of schistosomiasis-related parasite-host relationships, and understanding its gene regulation may aid in this endeavor. The ubiquitin-proteasome system (UPS) performs post-translational regulation in order to maintain cellular protein homeostasis and is related to several mechanisms, including immune responses. OBJECTIVE The aims of this work were to identify and characterise the putative genes and proteins involved in UPS using bioinformatic tools and also their expression on different tissues of B. glabrata. METHODS The putative genes and proteins of UPS in B. glabrata were predicted using BLASTp and as queries reference proteins from model organism. We characterised these putative proteins using PFAM and CDD software describing the conserved domains and active sites. The phylogenetic analysis was performed using ClustalX2 and MEGA5.2. Expression evaluation was performed from 12 snail tissues using RPKM. FINDINGS 119 sequences involved in the UPS in B. glabrata were identified, which 86 have been related to the ubiquitination pathway and 33 to proteasome. In addition, the conserved domains found were associated with the ubiquitin family, UQ_con, HECT, U-box and proteasome. The main active sites were lysine and cysteine residues. Lysines are responsible and the starting point for the formation of polyubiquitin chains, while the cysteine residues of the enzymes are responsible for binding to ubiquitin. The phylogenetic analysis showed an organised distribution between the organisms and the clades of the sequences, corresponding to the tree of life of the animals, for all groups of sequences analysed. The ubiquitin sequence was the only one with a high expression profile found in all libraries, inferring its wide range of performance. MAIN CONCLUSIONS Our results show the presence, conservation and expression profile of the UPS in this mollusk, providing a basis and new knowledge for other studies involving this system. Due to the importance of the UPS and B. glabrata, this work may influence the search for new methodologies for the control of schistosomiasis.