DEFAR - Departamento de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530

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Resultados da Pesquisa

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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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    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.