Obtenção e caracterização de sistemas particulados de quitosana para liberação gástrica de amoxicilina

The infection caused by Helicobacter pylori (H. pylori) is associated with gastroduodenal inflammation can lead to the development of gastritis, gastric or duodenal ulcer and gastric cancer (type 1 carcinogen for stomach cancer). Amoxicillin is used as first-line therapy in the treatment of H. pylori associated to metronidazole or clarithromycin, and a proton pump inhibitor. However, the scheme is not fully effective due to inadequate accumulation of antibiotics in gastric tissue, inadequate efficacy of ecological niche of H. pylori, and other factors. In this context, this study aimed to obtaining and characterization of particulate systems gastrorretentivos chitosan - amoxicillin aiming its use for treatment of H. pylori infections. The particles were obtained by the coacervation method / precipitation using sodium sulfate as precipitating agent and crosslinking and two techniques: addition of amoxicillin during preparation in a single step and the sorption particles prior to amoxycillin prepared by coacervation / precipitation and spray drying. The physicochemical characterization of the particles was performed by SEM, FTIR, DSC, TG and XRD. The in vitro release profile of amoxycillin free and incorporated in the particles was obtained in 0.1 N HCl (pH = 1.2). The particles have higher encapsulation efficiency to 80% spherical shape with interconnected particles or adhered to each other, the nanometric diameter to the systems obtained by coacervation / precipitation and fine for the particles obtained by spray drying. The characterization by FTIR, DSC and XRD showed that the drug was incorporated into the nanoparticles dispersed in the polymeric matrix. Thermal analysis (TG and DSC) indicated that encapsulation provides greater heat stability to the drug. Amoxicillin encapsulated in nanoparticles had slower release compared to free drug. The particles showed release profile with a faster initial stage (burst effect) reaching a maximum at 30 minutes 35% of amoxicillin for the system in 1: 1 ratio relative to the polymer and 80% for the system in the ratio 2: 1. Although simple and provide high encapsulation efficiency of amoxicillin, the process of coacervation, precipitation in one step using sodium sulfate as precipitant / cross-linker must be optimized in order to adjust the release kinetics according to the intended application.

Escravo moderno em discurso: figuras de ação e ação em discurso nas representações do agir humano

This work has as object of study a social practice: modern slavery of workers in the sugar cane, and aims to present a reflection on maintenance, eradication or modification of this practice. This reflection bases itself upon the concepts of discourse advocated by Critical Discourse Analysis (Fairclough, 2001, 2003, 2006 and Chouliaraki; Fairclough, 1999) associated with Sociodiscursive Interactionism (Bronckart, 1999, 2006, 2008), and the concept of action figures, proposed by Bulea (2010). We follow the five steps outlined in Chouliaraki and Fairclough (1999): a) emphasis on a social problem, b) introduction and discussion of obstacles to tackle the problem, c) considerations concern the problem in practice d) identifying possible ways to past the obstacles, and e) reflection about the analyst role within the problem. In order to achieve step (b) in its discourse materiality axis, it has been identified the thematic content, discourse types, enunciative mechanisms and action figures of testimonials of sugar cane workers and other subjects involved with the problem in the documentaries Bagaço (2006, and Tabuleiro de Cana, Xadrez de Cativeiro (2006). These documentaries bring to the screen a little of sugar cane workers reality within an overexploitation, human rights disrespects and forced work. The analysis of textual/discursive aspects of testimonials has shown the ways in which the (de)construction of the representation of sugar cane action allows understanding of how the problem emerges and how it is rooted in the organization of social life. The general result of this reflection point to the internalization of social practices deep-rooted in evaluations of the sugar cane worker subjective world and from social world values, opinions and rules. The results also show that, in their discourse, workers assume their slavery sometimes consciously, sometimes unconsciously, but only suggest a reaction against the oppression imposed on them because they have internalized and naturalized their enslavement.

Escravo moderno em discurso: figuras de ação e ação em discurso nas representações do agir humano

This work has as object of study a social practice: modern slavery of workers in the sugar cane, and aims to present a reflection on maintenance, eradication or modification of this practice. This reflection bases itself upon the concepts of discourse advocated by Critical Discourse Analysis (Fairclough, 2001, 2003, 2006 and Chouliaraki; Fairclough, 1999) associated with Sociodiscursive Interactionism (Bronckart, 1999, 2006, 2008), and the concept of action figures, proposed by Bulea (2010). We follow the five steps outlined in Chouliaraki and Fairclough (1999): a) emphasis on a social problem, b) introduction and discussion of obstacles to tackle the problem, c) considerations concern the problem in practice d) identifying possible ways to past the obstacles, and e) reflection about the analyst role within the problem. In order to achieve step (b) in its discourse materiality axis, it has been identified the thematic content, discourse types, enunciative mechanisms and action figures of testimonials of sugar cane workers and other subjects involved with the problem in the documentaries Bagaço (2006, and Tabuleiro de Cana, Xadrez de Cativeiro (2006). These documentaries bring to the screen a little of sugar cane workers reality within an overexploitation, human rights disrespects and forced work. The analysis of textual/discursive aspects of testimonials has shown the ways in which the (de)construction of the representation of sugar cane action allows understanding of how the problem emerges and how it is rooted in the organization of social life. The general result of this reflection point to the internalization of social practices deep-rooted in evaluations of the sugar cane worker subjective world and from social world values, opinions and rules. The results also show that, in their discourse, workers assume their slavery sometimes consciously, sometimes unconsciously, but only suggest a reaction against the oppression imposed on them because they have internalized and naturalized their enslavement.

O processo de urbanização de Mossorò: dos processos históricos à estrutura urbana atual

The general objective of this academic work is to analyze the relationship between the territorial division and the urban expansion process of Mossoró city, understood here as the production and occupation of space. The urban expansion in Mossoró, since its formation as settlement in 1772 until current days, identifies with the Brazilian urbanization process whose growth is determined by the capitalist development. Thus, the expansion was determined by several economical specializations imposed by the territorial division of work which occurs at an interregional level, and, sometimes at an international level. Then, each specialization determined a moment of the urban expansion of the city, as follows: a) The cattle farmer specialization, between 1772 and 1857, when the urban expansion was shy, is summarized to a commercial square that received goods from Aracati aiming to cover a wide rural area; b) The commercial emporium specialization, between 1857 and 1930, when the urban expansion took an important impulse with the concentration of public and private capitals; c) The salt industry and the agricultural-industrial exporter specialization inside a state of development policy, between 1930 and 1970, when the urban expansion, joined to the settlement of the working class in the urban soil, developed along an important axis -the railway; d) The render of services specialization inside a state of intervention policy, between 1970 and 1990, when the urban expansion was characterized by the accelerated growth rhythm, by the reuse of some spaces, and by space segregation of demanding people; e) The render of services policy inside a neoliberal state policy, since 1990 until current days, when the urban expansion reduced its rhythm abruptly, when only small alterations occurred in the existing spaces. It focused on social policies and on several slums eradication programs. Finally, the territorial structure is deeply articulated with others, no territorial, but economical, social and political, which happens at a national, regional and local rate. Only within a historical and conceptual panorama, it was possible to explain the urban expansion in Mossoró from its formation in 1772 until current days. Therefore, this work is a several discipline analysis of the urbanization process existing in Mossoró