A partir de um levantamento feito em periódicos qualis A1 e A2 e artigos publicados em todas as edições da Revista Brasileira de Educação do Campo (2016 - v.1. – Jan/jun a 2020 – v.5.), no total de 11 edições, procurou-se identificar os trabalhos que recorreram ao campo teórico dos Estudos Culturais Pós-Estruturalistas para fazerem suas análises. Este artigo resulta dos estudos bibliográficos de um projeto de pesquisa vinculado ao Departamento Acadêmico de Ciências Humanas e Sociais (DACHS) da Universidade Federal de Rondônia – UNIR - Campus de Ji-Paraná, que tem como objetivo identificar e analisar como são produzidas e negociadas as identidades e diferenças de crianças e jovens do campo de Ji-Paraná/RO, resultado da inserção no espaço educativo urbano. O projeto, em sua fase inicial, procurou investigar em periódicos científicos se os Estudos Culturais têm contribuído nas análises da Educação do Campo no Brasil. Entende-se que uma investigação a partir dos Estudos Culturais contribui para problematizar como crianças e jovens vitimados pela política pública de fechamento das escolas do campo foram se tornando reféns do transporte escolar para escolas urbanas. Constata-se que são ínfimos os estudos empreendidos no Brasil, que recorrem aos Estudos Culturais para problematizar a Educação do Campo.
Introduction: Gold nanoparticles (AuNP) have a wide bond affinity to proteins, antibodies, and antigens. These bioconjugates show high stability and are applied as biological markers in the lateral flow immunochromatography to obtain the rapid diagnostic kits. Quantum yield (QY) is one of the parameters which characterizes the fluorescence process of a material. It is defined as the number of emitted photons relative to the number of absorbed photons, so that the greater the QY value, the greater emitted radiation. Determining the QY is very important to identify the most promising nanoparticles able to produce diagnostic kits with more sensibility, to secure faster and earlier diagnosis.Objectives: This work aims to evaluate the effect of different stabilizers in the QY of AuNP applied on the in vitro diagnostic production.Methodology: Three fluorescent AuNP were synthesized in-house (Laboratory of Diagnostic Technology, Bio-Manguinhos) using HAuCl4.3H2O, as precursor, and tryptophan (AuNP-T), bovine serum albumin (AuNP-B) and pepsin (AuNP-P) as stabilizers. QY values and fluorescence spectra were obtained using a spectrofluorophotometer (Shimadzu RF-6000) equipped with 150 W Xenon arc lamp and 1-cm quartz cell. Maximum excitation (λ EX ) and emission (λ EM ) wavelengths of each AuNP were obtained from spectra scan from 250 to 800 nm. Fluorescein 0.05 mol L -1 solution (FS), prepared in NaOH 0.1 mol L -1 , was used as fluorescence standard. absorbance at maximum λEX, refractive index and emission spectra areas were other parameters used in the QY calculation.Results: AuNP solutions showed absorbance and refractive values of 0.07 and 1.333, respectively. AuNP-B, AuNP-P and AuNP-T showed maximum λ EX /λ EM in 510/651 (QY: 1.0%), 315/405 (QY: 0.10%) and 300/360 nm (QY: 4.3%), respectively. The highest QY value observed to AuNP-T agree with the results described in the literature and can be attributed to the presence of the tryptophan in its structure, which is the amino acid whose luminescent process has been studied for many years. Conclusion:Tryptophan was the stabilizer whose nanoparticle (AuNP-T) exhibited the highest QY value (4.3%), so that its fluorescence characteristic secures it as a potential nanoparticle to be applied on the in vitro diagnostic production.
Introduction: Gold nanoparticles (AuNPs) are often used as biosensors in biological markers and also in diagnostic kits. Spherical shaped AuNPs are red. These nanoparticles have high binding affinity with proteins, antibodies and antigens forming stable bioconjugates. Are widely used in lateral flow immunochromatography platform. Therefore, AuNPs are currently one of the main raw materials used to produce various diagnostic kits, including Sars-CoV-2. The assessment of their correct stability directly affects the customized production and quality of the diagnostics kits.Objectives: Evaluate the stability of in-house prepared gold nanoparticle solutions used in the manufacture of diagnostic tests using statistical methods for determining the appropriate shelf life under established storage conditions. Methodology:In-house based on adapted Turkevish method (1951), a gold nanoparticle (AuNP) solution was synthesized and characterized by ultraviolet-visible spectroscopy, inductively coupled plasma mass spectrometry (ICP-MS), dynamic scattering (DLS) and laser Doppler electrophoresis (LDE). The solution was analyzed at the time of manufacture (T0) and every 15 days for 90 days, under thermal stress conditions. The evaluation of the stability of the AuNP solution was based on the ISO Guide 35, which statistically evaluates the time that significant change occurs of the evaluation parameters, indicating the end of shelf life at a significance level of 0.05. Results:Statistical analysis shows that at T90 days, one of the evaluated parameters showed a significant change at a significance level of 0.05. |b1| > t95%, n-2 * s(b1) and, therefore, there is statistical evidence that proves that the final solution lost stability in this time. Arrhenius equation was used to determine the shelf life. Where, Storage=25°C, Stress=40°C, Activation Energy (Ea)=3, and then: Thermal Kinetic Ratio (Qt) = 5.2. That is, 2.5 months at 40°C is equivalent to 13 months at 25°C. Conclusion:AuNPs produced in-house have a shelf life of 1 month at room temperature. Based on the analysis of the main control parameters and statistical application, the validity attributable to the AuNP solution under study is 13 months at 25°C, bringing great savings to the production process, without loss of quality. New strategies for evaluating the stability of solutions should be considered in the future.
Introduction: Canine Visceral Leishmaniasis (CVL) is a zoonotic disease caused by Leishmania infantum that has increased the number of cases in urban regions over the years in Brazil. This disease is of great epidemiological importance and has dogs as the main domestic reservoir, deeply influencing the maintenance of the biological cycle of the transmitting vector. Infected dogs may develop the disease either symptomatically or asymptomatically. Due to the proximity between humans and dogs, the early diagnosis of this neglected disease is of extreme importance for the well-being of both. The diagnostic test currently commercialized by the public service in Brazil is the EIE-LVC, which uses the extract of Leishmania major as capture antigen, conferring good sensitivity, however, its specificity can be variable since there is a possibility of cross-reaction with other species of the Trypanosomatidae family.Objectives: In this scenario, the development of a highly sensitive and specific test for detection of CLV antibodies in animals is very urgent. Therefore, this study aims to develop and validate a recombinant ELISA to diagnose CVL. Methodology:To achieve the objective, we selected a Q5 recombinant protein, provided by the project collaborators, and already described in literature by the research group. The Q5 recombinant test, in inhouse experiments, demonstrated greater efficiency when compared to current commercial tests available on the market. A comparison between the Q5 recombinant protein assay and the EIE-LVC kit was performed using 68 positive and 77 negative samples confirmed in our Dual-Path Platform technology (DPP® CVL rapid test). The sensitivity and specificity calculation was performed using MedCalc Software.Results: Preliminary results obtained with the Q5 recombinant protein showed satisfactory performance in the detection of CVL antibodies. The protein reached the same sensitivity and specificity values as the commercial kit presenting a result of 98% (92% to 99%) and 95% (87% to 98%) respectively. Conclusion:As future prospects, it is planned to scale up the production of prototypes so that a multicentric validation of the kits can be carried out.
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