Caracterização por ressonância magnética nuclear de sucos de maçã obtidos por preparações enzimáticas

In this work, ¹H Nuclear Magnetic Resonance (¹H NMR) was employed to evaluate changes in apple juice in response to the addition of Panzym® Yieldmash and Ultrazym® AFP-L enzymatic complexes and compare it with premium apple juice. The juice was processed at different temperatures and concentrations of enzymatic complexes. The differences in the results were attributed mainly to the enzyme concentrations, since temperature did not cause any variation. A quantitative analysis indicated that the concentration of fructose increased while the concentrations of sucrose and glucose decreased in response to increasing concentrations of the enzymatic complexes.

RESSONÂNCIA MAGNÉTICA NUCLEAR DE SUBSTÂNCIAS ORGANOFLUORADAS: UM DESAFIO NO ENSINO DE ESPECTROSCOPIA

Nuclear magnetic resonance is a technique that is widely used for elucidating and characterizing organic substances. Organofluorine substances have applications in many areas from drugs to liquid crystals, but their NMR spectra are often challenging due to fluoride coupling with other nuclei. For this reason, NMR spectra of this class of substances are not commonly covered in undergraduate and graduate chemistry courses and related fields. Thus, the aim of this work was the presentation and discussion of 1H, 13C, and 19F NMR spectra of eleven organofluorine substances which, in the case of 1H and 13C nuclei, showed classic patterns of first-order coupling and the effects of the fluorine nucleus in different chemical and magnetic environments. In addition, the observation of long distance coupling constants was possible through the use of apodization functions in the processing of the spectra. It is expected that the examples presented herein can be utilized and discussed in undergraduate and graduate NMR spectroscopy disciplines and thus improve the teaching and future research of organofluorine compounds.

Determination of Copper, Iron, Nickel and Zinc in fuel kerosene by FAAS after adsorption and pre-concentration on 2-aminothiazole-modified silica gel

Silica gel chemically modified with 2-Aminotiazole groups, abbreviated as SiAT, was used for preconcentration of copper, zinc, nickel and iron from kerosene, normally used as a engine fuel for airplanes. Surface characteristics and surface area of the silica gel were obtained before and after chemical modification using FT-IR, Kjeldhal and surface area analysis (B.E.T.). The retention and recovery of the analyte elements were studied by applying batch and column techniques. The experimental parameters, such as shaking time in batch technique, flow rate and concentration of the eluent (HCl- 0.25-2.00 mol L-1) and the amount of silica, on retention and elution, have been investigated. Detection limits of the method for copper, iron, nickel and zinc are 0.77, 2.92, 1.73 and 0.097 mg L-1, respectively. The sorption-desorption of the studied metal ions made possible the development of a preconcentration method for metal ions at trace level in kerosene using flame AAS for their quantification.

Competências de Comunicação Clínica: Objetivos de Ensino-Aprendizagem para um Currículo Nuclear nas Áreas da Saúde

RESUMO Este ensaio destaca a importância das competências de comunicação clínica (CCC) nas ciências da saúde. Estas competências podem ser ensinadas, aprendidas e avaliadas, e vários estudos evidenciam para as vantagens de uma formação específica nesta área, potenciando a relação que os profissionais da área da saúde estabelecem com os pacientes, cuidadores informais e equipas de saúde, com resultados melhorados nos indicadores de saúde e cuidados mais humanizados. Confrontados com dificuldades na integração de programas específicos de comunicação nos curricula, assim como um défice no processo de avaliação e feedback estruturado, é crucial um investimento na formação pedagógica e no desenvolvimento curricular. Conscientes da escassez de trabalhos sistemáticos que apontam para um consenso sobre as competências e objetivos de ensino-aprendizagem das CCC, o sub-grupo Core Curriculum do comité de ensino (tEACH) da Associação Europeia de Comunicação em Saúde (EACH) desenvolveu e alcançou um consenso para um currículo nuclear nas diferentes áreas da saúde. Neste contexto, surgiu o Health Professions Core Communication Curriculum – HPCCC, que pode servir como referencial flexível de acordo com as necessidades específicas e contribuir para uma maior sistematização das iniciativas de CCC em saúde em língua portuguesa.

Microgeneration of electricity with producer gas in dual fuel mode operation

Among the alternatives to meet the increasing of world demand for energy, the use of biomass as energy source is one of the most promising as it contributes to reducing emissions of carbon dioxide in the atmosphere. Gasification is a technological process of biomass energy production of a gaseous biofuel. The fuel gas has a low calorific value that can be used in Diesel engine in dual mode for power generation in isolated communities. This study aimed to evaluate the reduction in the consumption of oil Diesel an engine generator, using gas from gasification of wood. The engine generator brand used was a BRANCO, with direct injection power of 7.36 kW (10 HP) coupled to an electric generator 5.5 kW. Diesel oil mixed with intake air was injected, as the oil was injected via an injector of the engine (dual mode). The fuel gas was produced in a downdraft gasifier. The engine generator was put on load system from 0.5 kW to 3.5 kW through a set of electrical resistances. Diesel oil consumption was measured with a precision scale. It was concluded that the engine converted to dual mode when using the gas for the gasification of wood decreased Diesel consumption by up to 57%.

Fuel consumption of a tractor in function of wear, of ballasting and tire inflation pressure

When using appropriate inflation pressures and load capacity (ballast), it may obtain a higher yield and prolongation of the life of the tire, besides it may minimize the problems of loss of traction, increased slippage and fuel consumption. This study aimed to evaluate the fuel consumption of a tractor operating with new and worn tires in three conditions of ballasting and three inflation pressures, when driving on compacted soil with vegetation cover. The experiment was conducted at the experimental unit from the Department of Animal Science, Federal University of Lavras, state of Minas Gerais, Brazil, in an agricultural soil compacted by cattle trampling and with vegetation cover. It was used a tractor 4x2 with front wheel assist, of a 65.62 kW engine power. The tires were of R1 type, diagonal (front: 12.4 to 24; and rear: 18.4 to 30), the average height of the clutches of the new tires were 0.3 and 0.35 m for front and rear tires, respectively, and for the worn tires were 0.018 and 0.0045 m, for the front and the rear tires, respectively. The results showed advantages for the tractor equipped with new tires.

Use of nuclear technique in samples for agricultural purposes

The concern related to environment is growing. Due to this, it is needed to determine chemical elements in a large range of concentration. The neutron activation technique (NAA) determines the elemental composition by the measurement of artificial radioactivity in a sample that was submitted to a neutron flux. NAA is a sensitive and accurate technique with low detection limits. An example of application of NAA was the measurement of concentrations of rare earth elements (REE) in waste samples of phosphogypsum (PG) and cerrado soil samples (clayey and sandy soils). Additionally, a soil reference material of the International Atomic Energy Agency (IAEA) was also analyzed. The REE concentration in PG samples was two times higher than those found in national fertilizers, (total of 4,000 mg kg-1 ), 154 times greater than the values found in the sandy soil (26 mg kg-1 ) and 14 times greater than the in clayey soil (280 mg kg-1 ). The experimental results for the reference material were inside the uncertainty of the certified values pointing out the accuracy of the method (95%). The determination of La, Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and Lu in the samples and reference material confirmed the versatility of the technique on REE determination in soil and phosphogypsum samples that are matrices for agricultural interest.

Alterações na expressão do antígeno nuclear de proliferação celular e dos receptores de estrogênio e de progesterona provocadas pela quimioterapia primária no carcinoma de mama

OBJETIVO: averiguar as alterações induzidas pela quimioterapia primária no fenótipo celular. MÉTODOS: avaliamos a expressão do antígeno nuclear de proliferação celular (PCNA) e dos receptores de estrogênio (RE) e de progesterona (RP) em 17 tumores de mama no estádio clínico II, obtidos antes e após a terapia antiblástica, por método imuno-histoquímico. Os valores foram relacionados com o estado menstrual, com a resposta clínica tumoral e com o comprometimento axilar. RESULTADOS: houve redução significante na porcentagem de células coradas pelo anti-PCNA antes (tempo A) e após (tempo B) a quimioterapia (p=0,041). Observamos também resultados significantes ao compararmos os índices médios de PCNA com o grau histológico GII/GIII [tempo A=63,1 e tempo B=38,7 (p=0,049)] e nos casos em que houve resposta clínica [tempo A=53,1 e tempo B=34,4 (p=0,011)]. Não observamos relação significante entre os índices de PCNA com o estado menstrual e o axilar. Houve redução significante do RE após a quimioterapia nas pacientes pré-menopausadas [tempo A=60,3 e tempo B=24,1 (p=0,027)] e naquelas que apresentaram resposta clínica ao tratamento [tempo A=59,1 e tempo B=37,9 (p=0,030)]. Observamos aumento significante do RP após a quimioterapia nas pacientes pós-menopausadas [tempo A=35,3 e tempo B=58,3 (p=0,023)]. Não encontramos relação entre os receptores hormonais e o comprometimento axilar. CONCLUSÕES: a diminuição dos índices de PCNA nos tumores de alto grau histológico, do RE nas pacientes pré-menopausadas e de ambos, PCNA e RE, nos tumores com redução clínica após a quimioterapia nos mostra que ela atuou sobre as células em proliferação e que o PCNA pode ser utilizado como parâmetro de resposta a este tratamento.

Carcinoma ductal in situ associado a carcinoma invasivo na mesma mama: análise do grau nuclear e da expressão das proteínas p53 e C-erbB-2 e dos receptores de estrógeno

OBJETIVOS: avaliar a variação do grau nuclear e da expressão das proteínas p53 e c-erbB-2 e dos receptores de estrógeno (RE) no carcinoma ductal in situ (CDIS) e no carcinoma invasivo, presentes na mesma mama. MÉTODOS: estudo descritivo retrospectivo com 38 mulheres com CDIS associado a carcinoma invasivo da mama. Foi avaliado o grau nuclear e o realizado estudo imunohistoquímico para expressão das proteínas p53 e c-erbB-2 e para os RE. Os casos considerados positivos para a expressão das proteínas e dos RE foram aqueles com contagem de células positivas igual ou superior a 10%. A concordância entre estas variáveis no componente in situ e invasivo foi avaliada pelo coeficiente kappa (k), interpretado de acordo com os critérios de Landis e Koch. O teste de MacNemar foi usado para testar diferenças entre os dois grupos. RESULTADOS: a concordância entre o grau nuclear e a expressão dos RE nos componentes in situ e invasivo foi de 0,89 para ambos, quase perfeita. A concordância para a expressão da proteína c-erbB-2 também foi considerada quase perfeita, com coeficiente de 0,84. Já a concordância entre a expressão da proteína p53 no componente in situ e no invasivo foi de 1,0, considerada perfeita. Não houve diferenças significativas entre o grau nuclear e as expressões das proteínas e dos RE nos componentes in situ e invasivo na mesma mama. CONCLUSÕES: existe concordância alta do grau nuclear e da expressão das proteínas p53 e c-erbB-2 no CDIS e no carcinoma invasivo presentes na mesma mama.

Diagnóstico pré-natal de gêmeos unidos com uso da ressonância nuclear magnética: relato de dois casos

A gemelaridade imperfeita é entidade bastante rara e de grande interesse para fetólogos e obstetras em geral. Sua incidência estimada varia de 1:50.000 a 1:200.000 nascimentos. Seu diagnóstico precoce se faz necessário, tendo em vista sua importância para o prognóstico da gestação, correta determinação da via de parto e o planejamento pós-natal. Os dois casos relatados são de gêmeos unidos diagnosticados no pré-natal através da ultra-sonografia e ressonância nuclear magnética, para estudo do compartilhamento dos órgãos e melhor definição das relações anatômicas. O primeiro par gemelar foi cefalópago, ou seja, unidos pela cabeça, tórax e abdome, com duas pelves e oito membros. O segundo foi toracópago, ou seja, unidos pelo tórax e abdome superior. A ressonância magnética pouco contribuiu para o diagnóstico de gêmeos unidos. Entretanto, se mostrou de grande auxílio na descrição dos órgãos compartilhados entre os fetos, contribuindo na definição do prognóstico fetal.

Comparison of nuclear grade and immunohistochemical features in situ and invasive components of ductal carcinoma of breast

PURPOSE:To compare the prognostic and predictive features between in situ and invasive components of ductal breast carcinomas. METHODS:We selected 146 consecutive breast samples with ductal carcinoma in situ (DCIS) associated with adjacent invasive breast carcinoma (IBC). We evaluated nuclear grade and immunohistochemical expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), cytokeratin 5/6 (CK5/6), and epidermal growth factor receptor (EGFR) in both components, in situ and invasive, and the Ki-67 percentage of cells in the invasive part. The DCIS and IBC were classified in molecular surrogate types determined by the immunohistochemical profile as luminal (RE/PR-positive/ HER2-negative), triple-positive (RE/RP/HER2-positive), HER2-enriched (ER/PR-negative/HER2-positive), and triple-negative (RE/RP/HER2-negative). Discrimination between luminal A and luminal B was not performed due to statistical purposes. Correlations between the categories in the two groups were made using the Spearman correlation method. RESULTS:There was a significant correlation between nuclear grade (p<0.0001), expression of RE/RP (p<0.0001), overexpression of HER2 (p<0.0001), expression of EGFR (p<0.0001), and molecular profile (p<0.0001) between components in situ and IBC. CK 5/6 showed different distribution in DCIS and IBC, presenting a significant association with the triple-negative phenotype in IBC, but a negative association among DCIS. CONCLUSIONS: Our results suggest that classical prognostic and predictive features of IBC are already determined in the preinvasive stage of the disease. However the role of CK5/6 in invasive carcinoma may be different from the precursor lesions.