¿Por qué las infancias son invisibles en la enseñanza de la historia? Un análisis sobre los Diseños Curriculares bonaerenses, materiales didácticos y representaciones de docentes y estudiantes en actuales escuelas secundarias

This article contains guidelines generated from a research work carried out with the purpose of analyzing the place that childhoods occupy as historical subjects in the study and teaching of history. In general terms, the results demonstrated that although the historiography of childhood (since its constitution as a field of studies) has managed to make visible the role of children as present and active subjects in the constitution and development of the various historical processes, their academic productions have had little impact (yet) on the school contents proposed by the Buenos Aires Curricular Designs, on those presented in didactic materials for school circulation and on those addressed in the classroom practices developed by teachers and students in current secondary schools.El presente artículo contiene lineamientos generados a partir de un trabajo de investigación realizado con la finalidad de analizar el lugar que ocupan las infancias como sujetos históricos en el estudio y la enseñanza de la historia. En líneas generales, los resultados demostraron que, si bien la historiografía de las infancias (desde su constitución como campo de estudios) ha logrado visibilizar el rol de los/as niños/as como sujetos presentes y activos en la constitución y desarrollo de los diversos procesos históricos, sus producciones académicas han tenido poco impacto (aún) en los contenidos escolares propuestos en los Diseños Curriculares bonaerenses, en los presentados en materiales didácticos de circulación escolar y en los abordados en las prácticas áulicas que desarrollan docentes y estudiantes en las actuales escuelas secundarias.El presente artículo contiene lineamientos generados a partir de un trabajo de investigación realizado con la finalidad de analizar el lugar que ocupan las infancias como sujetos históricos en el estudio y la enseñanza de la historia. En líneas generales, los resultados demostraron que, si bien la historiografía de las infancias (desde su constitución como campo de estudios) ha logrado visibilizar el rol de los/as niños/as como sujetos presentes y activos en la constitución y desarrollo de los diversos procesos históricos, sus producciones académicas han tenido poco impacto (aún) en los contenidos escolares propuestos en los Diseños Curriculares bonaerenses, en los presentados en materiales didácticos de circulación escolar y en los abordados en las prácticas áulicas que desarrollan docentes y estudiantes en las actuales escuelas secundarias

impact of probiotics and prebiotics targeting metabolic syndrome

Abstract Several studies are contributing to the better understanding of the impact of probiotics and prebiotics on the modulation of the intestinal microbiota and subsequent effects on the host's health. This review aimed to discuss the results of studies using different experimental models to evaluate the impact of the supplementation with probiotics and/or prebiotics on the different risk factors related to metabolic syndrome (MetS). A better understanding of the daily supplementation of probiotics and prebiotics regarding the mechanisms involved in the modulation of the intestinal microbiota and the immune system of patients suffering from this metabolic disorder is necessary to establish the efficiency of possible biomarkers that could contribute towards a health claim. Although the results might be promising, the functionality of probiotics and prebiotics on the intestinal microbiota and its relationship with MetS are still poorly understood to indicate their consumption for prevention and management of MetS in clinical practice

Isolation and identification of Bacillus strains with antimycobacterial activity

Tuberculosis is the principal cause of death worldwide due to an infectious disease. The resurgence of tuberculosis, followed by the increase in prevalence of infections caused by nontuberculous mycobacteria (NTM), as well as the multi-drug resistance of mycobacteria to the majority of currently available antibiotics, have encouraged research for new antimycobacterial agents. Soil and water samples from different Moroccan biotopes, have led to the isolation of four bacterial strains (M, R, G and S), showing an inhibitory effect on mycobacterial growth. This effect was shown to be due to secreted substances in the growth medium. From subsequent analysis it was concluded that these strains produced different active substances. Sequencing of the 16S rRNA showed that these isolates belong to the genus Bacillus. The active substance from isolate M, showed the more important inhibitory effect on mycobacterial growth. It is precipitated with ammonium sulfate and lost all activity when treated with Proteinase K, revealing its protein nature

Textura instrumental e avaliação sensorial de queijo fresco cremoso simbiótico: implicações da adição de Lactobacillus paracasei e inulina

Avaliou-se o efeito da adição do probiótico Lactobacillus paracasei e da fibra prebiótica inulina sobre o perfil de textura e as características sensoriais de queijo fresco cremoso. Três tratamentos de queijo fresco cremoso foram preparados em quintuplicata, em escala piloto, todos suplementados com uma cultura starter de Streptococcus thermophilus (T1, T2 e T3). L. paracasei subsp. paracasei foi adicionado em T1 e T2. Inulina foi adicionada em T2. O perfil de textura instrumental foi determinado após 1, 7, 14 e 21 dias de armazenamento. A análise sensorial foi conduzida aos 7 dias de armazenamento dos queijos. A presença de Lactobacillus paracasei nos queijos T1 e T2 e de inulina em T2 não alterou significativamente o perfil de textura (p>;0,05). Os queijos T1 apresentaram a menor preferência na análise sensorial e diferiram significativamente de T2 e T3 (p;0,05). A adição de inulina ao queijo fresco cremoso produzido com a suplementação de uma cepa potencialmente probiótica de Lactobacillus paracasei resultou em um produto com características adequadas e com propriedades funcionais agregadas.The influence of the addition of a potential probiotic culture of Lactobacillus paracasei and of the prebiotic fiber inulin on the texture profile and on the sensory evaluation of probiotic and synbiotic fresh cream-cheeses was monitored. Three cheese-making trials were prepared in quintuplicate, all supplemented with a Streptococcus thermophilus starter culture (T1, T2 and T3). L. paracasei subsp. paracasei was added to T1 and T2, and inulin, to T2. The instrumental texture profile was determined after 1, 7, 14 and 21 days of storage of the cheeses. Sensory evaluation was performed after 7 days of storage. The presence of Lactobacillus paracasei in cheeses T1 and T2 and of inulin in cheeses T2 did not alter the texture profile significantly. Cheeses T1 were the least preferred in the sensory evaluation and differed significantly from T2 and T3, due to acidic taste, according to panelists. On the other hand, T2 was the most preferred one, though not significantly different from T3. The addition of the prebiotic ingredient inulin to fresh cream cheese processed with a potentially probiotic Lactobacillus paracasei strain resulted in a product with appropriate features and with aggregated functional properties

Overcoming hurdles through innovation, persistence and creativeness in the development of probiotic foods

O propósito da administração de produtos probióticos é resultar em microbiota intestinal balanceada, a qual, por sua vez, terá um impacto favorável sobre a saúde do consumidor. Uma seleção adequada de cepas deve ser conduzida para o processamento de produtos alimentícios probióticos. Essa seleção visa garantir a sobrevivência desses microrganismos à passagem pelo trato gastrintestinal, após a manutenção de sua viabilidade no próprio produto-alvo, durante a sua elaboração e o seu armazenamento, bem como conferir propriedades tecnológicas adequadas a esse produto. O veículo alimentício escolhido para a incorporação de cepas probióticas deve ser cuidadosamente estudado para a seleção conveniente do par cepa probiótica-veículo, particularmente nos produtos fermentados, para os quais a multiplicação de probióticos pode resultar em características não peculiares ou mesmo indesejáveis ao produto. A verificação da compatibilidade e adaptabilidade entre as cepas selecionadas e os referidos veículos é fundamental. Esses pré-requisitos representam desafios tecnológicos significativos, uma vez que muitas bactérias probióticas são sensíveis à exposição a oxigênio, calor e ácidos. Diversos produtos lácteos probióticos, principalmente fermentados, e alguns não-lácteos, vêm sendo desenvolvidos. Os principais desafios encontrados no desenvolvimento e armazenamento desses produtos funcionais são discutidos no presente artigo.The aim of probiotic products is to achieve a balanced intestinal microbiota that will impact favorably on the consumer health. An adequate strain selection must be carried out to manufacture probiotic food products. This selection should guarantee adequate probiotic survival during the passage through the gastrointestinal tract, after retaining its viability in the target product, both during manufacture and storage, in addition to providing the product with suitable technological properties. The food matrix to be selected for the incorporation of probiotic strains should be carefully studied for the adequate probiotic strain-food matrix pair selection, especially for fermented products, in which probiotic growth might result in atypical or even undesirable changes. Compatibility of the selected strains and adaptability to the food must also be verified. These prerequisites are major technological challenges, as many probiotic strains are sensitive to oxygen, heat and acids. A number of probiotic dairy products, mainly fermented ones, in addition to certain non-dairy products have been developed. The main challenges faced during the development of these products and storage are discussed in the present review