Caracterização de solos sob diferentes usos na região sul do Amazonas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação da citotoxicidade de extratos, frações e substâncias puras de Pterogyne nitens em Trypanosoma cruzi e em macrófagos

A atividade biológica de extratos, frações e substâncias puras de Pterogyne nitens foi avaliada em formas epimastigotas das cepas Y e Bolívia de Trypanosoma cruzi, e a citotoxicidade das substâncias com potente atividade tripanocida foi testada em macrófagos murinos pelo método colorimétrico de redução do sal 3-(4,5-dimetiltiazol-2-il)-2-5-difeniltetrazólio (MTT) a formazana, um produto colorido. As mesmas amostras foram também avaliadas quanto a um possível sinergismo com o fármaco benzonidazol. Foram consideradas substâncias ativas contra o parasito: nitensidinas A, D, E e ácido cafeico, com concentrações inibitórias (CI50) inferiores às do benzonidazol (9,01 µg/mL para cepa Y e 25,00 µg/mL para cepa Bolívia). Essas substâncias foram avaliadas quanto a sua citotoxicidade em macrófagos de camundongos isogênicos Balb/c e C57/Black não infectados utilizando-se o mesmo método colorimétrico. Além disso, essas mesmas substâncias foram analisadas em diferentes tempos: 2, 6, 24, 48 e 72 horas, a fim de detectar-se o seu tempo mínimo de ação nos parasitos que foram então observados quanto à sua morfologia através de microscopia de contraste de fase. Os resultados indicam que não há toxicidade seletiva, ou seja, as moléculas se mostraram tóxicas tanto para as cepas testadas do parasito, quanto para macrófagos murinos das linhagens utilizadas. Modificações nas estruturas químicas podem ser sugeridas para que as substâncias continuem ativas contra Trypanosoma cruzi e se tornem menos tóxicas para células de mamíferos

Efeito da associação de antimicrobiano e óleo essencial na atividade antimicrobiana e propriedades físico-químicas de cimentos endodônticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Micropartículas de quitosana estruturadas com aerosil®: estabilidade, adsorção, encapsulação e liberação de substâncias ativas

Biodegradable microspheres used as controlled release systems are important in pharmaceutics. Chitosan biopolymer represents an attractive biomaterial alternative because of its physicochemical and biological characteristics. Chitosan microspheres are expected to become promising carrier systems for drug and vaccine delivery, especially for non-invasive ways oral, mucosal and transdermal routes. Controlling the swelling rate and swelling capacity of the hydrogel and improving the fragile nature of microspheres under acidic conditions are the key challenges that need to be overcomed in order to enable the exploration of the full pharmaceutical potential use of these microparticles. Many studies have focused on the modification of chitosan microsphere structures with cross-linkers, various polymers blends and new organic-inorganic hybrid systems in order to obtain improved properties. In this work, microspheres made of chitosan and nanosized hydrophobic silica (Aerosil R972) were produced by a method consisting of two steps. First, a preparation of a macroscopically homogeneous chitosan-hydrophobic silica dispersion was prepared followed by spray drying. FTIR spectroscopy, X-ray powder diffraction, differential scanning calorimetry, thermal gravimetric analysis, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (TEM) were used to characterize the microspheres. Also, the were conducted acid stability, moisture sorption capacity, release properties and biological assays. The chitosan-hydrophobic silica composite microspheres showed improved thermal degradation, lower water affinity, better acid stability and ability to retard rifampicin and propranolol hydrochloride (drug models) release under simulated physiological conditions. In vitro biocompatibility studies indicated low cytotoxicity and low capacity to activate cell production of the pro-inflammatory mediator nitric oxide. The results show here encourage further studies on the use of the new chitosan-hydrophobic silica composite microspheres as drug carrier systems via oral or nasal routes.

Qualidade da água de um reservatório e do solo da zona ripária sob diferentes usos na região semiárida do Rio Grande do Norte

Reservoirs are artificial ecosystems intermediate between rivers and lakes widely used in the Brazilian semiarid region as a way to provide water supply due to the said region’s water scarcity. The use of water from these supply sources for multiple uses, along with occupation and utilization of its riparian zone without proper management, directly influences the increased nutrient flow into aquatic environments, there with contributing to the acceleration of eutrophication. The semi-arid region is characterized by peculiar weather conditions, such as severe evaporation, high temperatures with little variation throughout the year and long water residence time, making it susceptible to prolonged drought occurrence, which tends to concentrate the nutrients in reservoirs, which favors the development of eutrophic conditions. Moreover, it is common soil use and occupation by carrying out activities with potential environmental impact on natural resources such as agriculture, livestock farming and lack of sanitation. The aim of this study is both to evaluate the water quality of the Cruzeta Reservoir, located in the semiarid region of Rio Grande do Norte, during a prolonged drought period, and assess the quality of its riparian zone soil under different uses, by monitoring physical-chemical variables. Along the prolonged drought, high levels of turbidity, suspended solids, nutrients and chlorophyll a were verified as present, therefore featuring low water quality. In the riparian zone of Cruzeta Reservoir, the areas under use of agriculture and livestock farming appeared as one of the main diffuse sources of nutrients to the said reservoir, featuring the highest levels of phosphorus and nitrogen in the soil, originated from decomposition of animal excreta and from the use of fertilizers, creating a tendency to increased eutrophication of such water supply source. The indicators of water and soil quality are useful for monitoring and evaluating the conservation status of natural resources, allowing the control and mitigation of the reservoir eutrophication process. This study confirmed the hypothesis that the reduction of water level, resulting from prolonged drought event, aggravates the symptoms of eutrophication; and also that using the soil under severalways modifies the physic chemical properties of the soil, having livestock farming and agriculture as the usages with greatest potential towards yielding P and N to the aquatic environment.

O Ensino de ligações químicas por meio do conceito de energia: uma proposta didática para o ensino médio

This work presents discussions on the teaching of Chemical Bonds in high school and some implications of this approach in learning chemistry by students. In general, understanding how the chemicals combine to form substances and compounds, it is a key point for understanding the properties of substances and their structure. In this sense, the chemical bonds represent an extremely important issue, and their knowledge is essential for a better understanding of the changes occurring in our world. Despite these findings, it is observed that the way in which this concept is discussed in chemistry class has contributed, paradoxically, to the emergence of several alternative designs, making the understanding of the subject by students. It is believed that one of the explanations for these observations is the exclusive use of the "octet rule" as an explanatory model for the Chemical Bonds. The use of such a model over time eventually replace chemical principles that gave rise to it, transforming knowledge into a series of uninteresting rituals and even confusing for students. Based on these findings, it is deemed necessary a reformulation in the way to approach this content in the classroom, taking into account especially the fact that the explanations of the formation of substances should be based on the energy concept, which is fundamental to understanding how atoms combine. Thus, the main question of the survey and described here of the following question: Can the development of an explanatory model for the Chemical Bonds in high school based on the concept of energy and without the need to use the "octet rule"? Based on the concepts and methodologies of modeling activity, we sought the development of a teaching model was made through Teaching Units designed to give subsidies to high school teachers to address the chemical bonds through the concept of energy. Through this work it is intended to make the process of teaching and learning of Chemical Bonds content becomes more meaningful to students, developing models that contribute to the learning of this and hence other basic fundamentals of chemistry.

O Ensino de ligações químicas por meio do conceito de energia: uma proposta didática para o ensino médio

This work presents discussions on the teaching of Chemical Bonds in high school and some implications of this approach in learning chemistry by students. In general, understanding how the chemicals combine to form substances and compounds, it is a key point for understanding the properties of substances and their structure. In this sense, the chemical bonds represent an extremely important issue, and their knowledge is essential for a better understanding of the changes occurring in our world. Despite these findings, it is observed that the way in which this concept is discussed in chemistry class has contributed, paradoxically, to the emergence of several alternative designs, making the understanding of the subject by students. It is believed that one of the explanations for these observations is the exclusive use of the "octet rule" as an explanatory model for the Chemical Bonds. The use of such a model over time eventually replace chemical principles that gave rise to it, transforming knowledge into a series of uninteresting rituals and even confusing for students. Based on these findings, it is deemed necessary a reformulation in the way to approach this content in the classroom, taking into account especially the fact that the explanations of the formation of substances should be based on the energy concept, which is fundamental to understanding how atoms combine. Thus, the main question of the survey and described here of the following question: Can the development of an explanatory model for the Chemical Bonds in high school based on the concept of energy and without the need to use the "octet rule"? Based on the concepts and methodologies of modeling activity, we sought the development of a teaching model was made through Teaching Units designed to give subsidies to high school teachers to address the chemical bonds through the concept of energy. Through this work it is intended to make the process of teaching and learning of Chemical Bonds content becomes more meaningful to students, developing models that contribute to the learning of this and hence other basic fundamentals of chemistry.

Sociabilidades e hedonismos: etnografia entre jovens usuários de substâncias psicoativas sintéticas Fortaleza Ceará

This dissertation shows a comparison between practices related to the body, to identities and to the health of young drug takers of synthetic and manipulated psychoactive substances living in Fortaleza. Through ethnographic accompaniment of parties and two social nets of young people I was able to verify the differences and similarities that make these addicted singular and plural in their notion of ethos and world vision. Notions of being hippie/alternative and being punk are present between these nets. Because their use and circulation are developed in environments usually distinct, it is possible to trace singular aspects between the nets and its actions. In parallel, on the attempt to build a triangulated data, I had information related to youth and drugs in local media and in governmental institutions bound to health mental and city security policies. With this junction of data I present a perspective to questions evolving formal and informal important controls to the conduction of their lives and identities. I present this as a sequel to well developed studies in Brasil about youth in interface to drug use, although still not very explored in the state of Ceará.

Obtenção de concentrado proteico do farelo de arroz e avaliação das propriedades químicas e funcionais

Esta dissertação é composta por 5 artigos.

Perto de ti, matas. Longe de ti, eu morro: Uma etnografia sobre usos de drogas de rua

O presente documento apresenta uma etnografia, realizada numa freguesia de Vila Nova de Gaia, sobre o uso, em contexto de rua, de substâncias denominadas "pesadas". Partindo de uma linha teórico­ metodológica que se demarca dos paradigmas tradicionais que perspectivam o fenómeno droga através das dimensões da delinquência ou da patologia, procedemos a uma análise, em contexto natural, dos espaços e actores relacionados com o psicotropismo. Concluímos que uma relação de dependência com as drogas emerge de uma dimensão processual, para a qual contribui o contexto sociocultural e o quadro relacional onde o indivíduo se insere. Daí, recorrermos ao conceito de itinerário de consumo na abordagem das relações estabelecidas com as substâncias. ABSTRACT; This document presents an ethnography, developed in Vila Nova de Gaia, about consumption, in street environment, of as common sense defines "hard" drugs. Through a theoretical and methodological approach that makes a difference among the traditional paradigms, which conceive the drug phenomenon under the delinquency and pathological dimensions, we analyse, in natural environment, the places and the actors which are involved in the drug scene. We concluded that the drug addiction relationship comes from a sequential dimension, in which sociocultural environment and relationship background make a contribution. Is that the reason why we use consumption itinerary concept to approach the relations between individual and drugs.

Sociabilidades e hedonismos: etnografia entre jovens usuários de substâncias psicoativas sintéticas Fortaleza Ceará

This dissertation shows a comparison between practices related to the body, to identities and to the health of young drug takers of synthetic and manipulated psychoactive substances living in Fortaleza. Through ethnographic accompaniment of parties and two social nets of young people I was able to verify the differences and similarities that make these addicted singular and plural in their notion of ethos and world vision. Notions of being hippie/alternative and being punk are present between these nets. Because their use and circulation are developed in environments usually distinct, it is possible to trace singular aspects between the nets and its actions. In parallel, on the attempt to build a triangulated data, I had information related to youth and drugs in local media and in governmental institutions bound to health mental and city security policies. With this junction of data I present a perspective to questions evolving formal and informal important controls to the conduction of their lives and identities. I present this as a sequel to well developed studies in Brasil about youth in interface to drug use, although still not very explored in the state of Ceará.

INST-D 2014. 401 Usos del torno cerámico

Video 2.06', formato 640 x 480 ancho. mp4.

Seleção de clones de aceroleira por meio de técnicas multivariadas aplicadas a características físico-químicas de frutos.

A aceroleira (Malpighia emarginata DC.) é uma das principais espécies frutíferas cultivadas 9 no Submédio do Vale do São Francisco e representa uma atividade estratégica para pequenos e médios produtores familiares, uma vez que sua produção é bem distribuída ao longo do ano, permitindo até oito colheitas anuais. Desse modo, compreende-se que essa cultura tem destacado valor para o desenvolvimento social, considerando a sua capacidade de geração de empregos e renda. Estima-se que a área plantada com aceroleiras na região ocupe cerca de 1000 ha (SOUZA et al., 2013). As acerolas são excelentes fontes naturais de vitamina C, com teores de ácido ascórbico que podem alcançar mais de 4000 mg.100g-1 de polpa, nos frutos imaturos. Para efeito de comparação, registra-se que, em laranjas, o teor médio de vitamina C é de 60 mg.100g-1 (USDA, 2015). Além disso, a acerola é uma excelente fonte de vitamina A e outras substâncias antioxidantes importantes na prevenção de doenças relacionadas a processos degenerativos. Desde 2012, a Embrapa Semiárido mantém uma coleção de acessos de germoplasma de aceroleira oriundos de diferentes regiões do Brasil e desenvolve um programa de melhoramento, que tem como um de seus alvos a obtenção de clones que produzam acerolas com características organolépticas mais adequadas ao consumo in natura (SOUZA et al., 2013). Neste contexto, a avaliação dos genótipos disponíveis quanto à qualidade dos frutos é fundamental para a seleção de clones promissores. O presente trabalho objetivou selecionar genótipos de aceroleira, utilizando a técnica de agrupamento por variáveis canônicas, baseado em caracteres físico-químicos dos frutos.

Óxido nítrico: propriedades e potenciais usos terapêuticos

Nitric oxide ( NO) is a substance that acts as a second-messenger and is associated with a number of important physiological functions such as regulation of the vascular tonus, immune modulation and neurotransmission. As a physiological mediator, alteration of its concentration level may cause pathophysiological disfunctions such as hypertension, septic shock and impotence. Possible therapeutic approaches are being developed to control NO levels in vivo. We review herein the main physical and chemical properties of NO, its biological functions and available chemical interventions to reduce and increment its physiological concentration levels. Recent developments in the field are also highlighted.

Surfactina: propriedades químicas, tecnológicas e funcionais para aplicações em alimentos

Surfactin, a lipopeptide produced by strains of Bacillus subtilis, has been proved to be a suitable biosurfactant in several applications. For many years, it has been investigated mainly for oil recovery and environmental usage. Its chemical, technological and functional characteristics turn surfactin into an attractive compound for several utilizations. In this review we emphasize some aspects of surfactin as a new food ingredient and its potential pharmaceutical and health applications.