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The effects of environmental conditions on activity, feeding, and body weight in male and female adolescent rats /Tomchesson, Joshua L January 2006 (has links) (PDF)
Thesis (Ph.D.)--Uniformed Services University of the Health Sciences, 2006 / Typescript (photocopy)
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The relationship between leader emotional intelligence and psychological climate: An exploratory studyKlem, Carlien 04 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: An exploratory study, conducted in a clothing manufacturing plant, investigated the presence of a single
psychological climate in an organisation, as well as the relationship between two increasingly important
constructs namely: leader emotional intelligence and the psychological climate of an organisation. Of a
total employee population of 1725 a sample of 600 participants were drawn. 297 Completed responses
were returned for analyses. An Exploratory Factor Analysis (EFA) was conducted on both The
Swinburne University Emotional Intelligence Test (SUEIT), which is designed to measure emotional
intelligence, and the Organisational Climate Questionnaire of Koys and DeCotiis, which measures
psychological climate. Stepwise discriminant analysis provided evidence to accept the proposition that a
single psychological climate existed in the organisation. The results of a Pearson correlation analysis,
multiple regression and discriminant analysis indicated that emotional intelligence is significantly,
positively related to psychological climate as a dependant variable. / AFRIKAANSE OPSOMMING: 'n Eksploratiewe studie is onderneem in 'n klere vervaardigingsonderneming om ondersoek in te stel na
die aanwesigheid van 'n enkel sielkundige klimaat, asook die verwantskap tussen twee belangrike
konstrukte, naamlik emosionele intelligensie en sielkundige klimaat in 'n organisasie. 'n Steekproef van
600 deelnemers is geneem uit 'n populasie van 1725 waarvan 297 voltooide antwoorde ontvang en
geanaliseer is. 'n Eksploratiewe Faktor Analise (EFA) is op beide die Swinburne Universiteit Emosionele
Intelligensie Toets (SUIET), en die Organisasie Klimaat Vraelys van Koys en De Cotiis, wat
onderskeidelik emosionele intelligensie en sielkundige klimaat meet, uitgevoer. Bewyse deur middel van
stapsgewyse diskriminante analise is ingewin om die hipotese te aanvaar dat 'n enkel sielkundige klimaat
in die organisasie aanwesig is. Die resultate van 'n Pearson korrelasie, meervoudige regressie en
diskrimante analise het aangedui dat emosionele intelligensie beduidend, positief verwant is aan
sielkundige klimaat as 'n afhanklike veranderlike.
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Intermetropolitan Networks of Co-invention in American BiotechnologyJanuary 2011 (has links)
abstract: Regional differences of inventive activity and economic growth are important in economic geography. These differences are generally explained by the theory of localized knowledge spillovers, which argues that geographical proximity among economic actors fosters invention and innovation. However, knowledge production involves an increasing number of actors connecting to non-local partners. The space of knowledge flows is not tightly bounded in a given territory, but functions as a network-based system where knowledge flows circulate around alignments of actors in different and distant places. The purpose of this dissertation is to understand the dynamics of network aspects of knowledge flows in American biotechnology. The first research task assesses both spatial and network-based dependencies of biotechnology co-invention across 150 large U.S. metropolitan areas over four decades (1979, 1989, 1999, and 2009). An integrated methodology including both spatial and social network analyses are explicitly applied and compared. Results show that the network-based proximity better defines the U.S. biotechnology co-invention urban system in recent years. Co-patenting relationships of major biotechnology centers has demonstrated national and regional association since the 1990s. Associations retain features of spatial proximity especially in some Midwestern and Northeastern cities, but these are no longer the strongest features affecting co-inventive links. The second research task examines how biotechnology knowledge flows circulate over space by focusing on the structural properties of intermetropolitan co-invention networks. All analyses in this task are conducted using social network analysis. Evidence shows that the architecture of the U.S. co-invention networks reveals a trend toward more organized structures and less fragmentation over the four years of analysis. Metropolitan areas are increasingly interconnected into a large web of networked environment. Knowledge flows are less likely to be controlled by a small number of intermediaries. San Francisco, New York, Boston, and San Diego monopolize the central positions of the intermetropolitan co-invention network as major American biotechnology concentrations. The overall network-based system comes close to a relational core/periphery structure where core metropolitan areas are strongly connected to one another and to some peripheral areas. Peripheral metropolitan areas are loosely connected or even disconnected with each other. This dissertation provides empirical evidence to support the argument that technological collaboration reveals a network-based system associated with different or even distant geographical places, which is somewhat different from the conventional theory of localized knowledge spillovers that once dominated understanding of the role of geography in technological advance. / Dissertation/Thesis / Ph.D. Geography 2011
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Social cognition in early schizophrenia: exploratory factor analysis and subcortical biomarkersMike, Luke T. 13 July 2017 (has links)
BACKGROUND: One of the central determinants of functional outcome in schizophrenia is social cognition (SC). With the wide array of SC domains, factor-analysis provides a powerful tool to identify commonalities amongst their underlying dysfunctions and its neural underpinnings.
METHODS: The present study performed exploratory factor analysis (EFA) on 93 patients with early course schizophrenia using eight validated SC subtests. Factors derived from this analysis were then used to investigate their relationships with neurocognitive performance, clinical symptoms, and functional outcome. Moreover, subsequent shape analysis of the amygdala and hippocampus was performed using the MAGeT Brain pipeline to investigate their relationship to the composite scores of SC factors.
RESULTS: EFA revealed a 3-factor solution, representing the domains of emotion management, emotion recognition, and theory of mind-social contextual appraisal, together accounting for 63.58% of the variance. Interestingly, only the theory of mind-social context appraisal factor correlated with measures of functional outcome. Addition analysis revealed that higher score on the theory of mind factor is significantly related with higher functional outcome measures and verbal learning performance, as well as with lower negative symptoms. Both emotion management and emotion perception factors indicated significant positive correlations with attention-vigilance while only emotion perception significantly correlated with visual learning and memory. Outward convexity of the right amygdala was identified to be positively correlated with the theory of mind-social context appraisal factor (p<0.05, FDR corrected), while the left and right hippocampus, specifically greater surface area of the dorsal-medial and ventral-lateral aspect of the hippocampus respectively, were positively correlated with higher composite score on theory of mind factor (p<0.05, FDR corrected).
CONCLUSION: Our EFA indicates overlap amongst SC subtests which represent three different SC subdomains. Furthermore, shape analysis reveals that displacement and surface area of the amygdala and hippocampus respectively play a role in theory of mind. In the future, the SC factors that we identified, along with their neural correlates, could provide essential diagnostic tools to assess SC functioning in early schizophrenia patients, as well as identify strategies for potential improvement following cognitive remediation therapy.
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Exploring experiences and self-explanations of antisocial offending behaviours of a group of South African emerging adultsFaroa, Brendon Duran January 2018 (has links)
Magister Artium - MA (Psychology) / Antisocial offending behaviour relate to instances of criminal and societal norm violating behaviour. In South
Africa, statistics on antisocial offending behaviour reflect high incidence rates among South African young
people who engage in societal norm violations that are largely aggressive and criminal in nature. In the
country's prisons, the average inmate is a young substance abuser who is unemployed, has dropped out of
school before high school, is functionally illiterate and, more often than not, homeless. This is particularly true
for emerging adults (those between the ages of 18 and 25 years) who constitute the poorest economic age
group, the average house burglar as well as make up more than a quarter of the prison population in South
Africa. In South Africa as well as internationally, the antisocial offending behaviour of emerging adults
remain grossly understudied especially through qualitative self-explanations. The present study utilised a
qualitative research approach to explore experiences and self-explanations regarding antisocial offending
behaviours of a group of 10 South African emerging adults. The study used an exploratory research design.
Participants were drawn from a number of non- government organisations, and two townships in Cape Town
which is located in the Western Cape Province of the Republic of South Africa.
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Um estudo da percepção dos consumidores frente aos atributos do selo orgânico Brasil em alimentos / A study of consumers perception to the attributes of the organic seal Brazil in foodsLima, Anderson Rodolfo de 22 February 2018 (has links)
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Previous issue date: 2018-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Como meio de diferenciar os atributos de produtos orgânicos frente aos produtos convencionais, os selos orgânicos começaram a ser utilizados na década de 1990. Os selos orgânicos são emitidos por instituições certificadoras credenciadas e independentes, as quais atestam que determinado produto é orgânico. No entanto, a identificação e a compreensão das informações agregadas aos produtos orgânicos pelos selos podem não ser facilmente percebíveis aos consumidores. Diante desse contexto, o presente trabalho tem como objetivo avaliar a percepção dos consumidores no que se refere aos atributos dos alimentos com certificados de orgânicos no Brasil. Para tanto, os dados foram coletados por meio da aplicação de um survey, utilizando como instrumento de coleta questionários semiestruturado. A aplicação do instrumento foi feita por meio da internet com 148 consumidores em dezembro de 2017 que reconhecem o selo de produto orgânico do Brasil. Os dados coletados foram analisados por meio de estatística descritiva e da Análise Fatorial Exploratória. Os resultados encontrados nesta pesquisa apontaram que o consumidor percebe 24 atributos relevantes no selo orgânico do Brasil (dentre 26 atributos), quando desenvolvida a análise estatística descritiva dos dados. Além disso, a análise multivariada considerou que a percepção dos consumidores sobre o selo orgânico considerou três grandes fatores, “Respeito ao trabalhador”, “Respeito ao meio ambiente” e “Bem-estar animal e associativismo”. / As a means of differentiating the attributes of organic products from conventional products, organic labels began to be used in the 1990s. Organic labels are issued by accredited and independent certifying institutions, which attest that a particular product is organic. However, identification and understanding of the information aggregated to organic products by labels may not be easily perceived by consumers. In view of this context, the present study aims to evaluate consumers' perceptions regarding the attributes of foods with organic certificates in Brazil. To do so, the data were collected through the application of a survey, using semi-structured questionnaires as a collection instrument. The application of the instrument was done through the internet with 148 consumers in December 2017 who recognize the Brazilian organic product label. The collected data were analyzed through descriptive statistics and the Exploratory Factor Analysis. The results found in this research indicate that the consumer perceives 24 relevant attributes in the Brazilian organic label (among 26 attributes), when the descriptive statistical analysis of the data was developed. In addition, the multivariate analysis considered that the perception of consumers on the organic label considered three major factors: "Respect for the worker", "Respect for the environment" and "Animal welfare and associativism".
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An investigation into the relationship between exposure to violence, resilience and PTSD in a sample of psychology students at the University of the Western CapeNortje, Carla Anne January 2018 (has links)
Magister Artium - MA (Psychology) / Post-apartheid South Africa has been marked by high levels of trauma resulting from
exposure to violence. Many South Africans are therefore at risk for developing Posttraumatic
Stress Disorder (PTSD). Despite a large body of research identifying various protective
factors which may influence an individual's response to a traumatic event, a gap in South
African research on the relationship between exposure to multiple traumatic experiences,
protective factors and the development of PTSD was identified. Therefore, located within the
systems theory framework, the aim of this study was to investigate the relationship between
demographic characteristics, types of exposure to trauma and resilience associated with the
development of posttraumatic stress (PTS) when there are multiple exposures to trauma. A
quantitative, cross-sectional, exploratory study on 158 psychology students at the University
of the Western Cape was undertaken. Using a non-random, convenience sampling method,
data were collected by means of four self-report questionnaires namely; a biographical
questionnaire, the Life Events Checklist for DSM-5 (LEC-5), the Resilience Scale for Adults
(RSA), and the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5).
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Uma abordagem unificada para análise exploratória e simulação interativa visual / An unified approach to visual exploratory analysis and interactive simulationFreitas, Carla Maria Dal Sasso January 1994 (has links)
Análise exploratória visual e simulação interativa visual são duas áreas afins, porém tratadas separadamente até o momento. 0 trabalho relatado neste texto objetivou a abordagem unificada destas duas classes de problemas, a partir da identificação de ambas com as questões de linguagens visuais, visualização de dados e de programas. A partir de estudos de casos considerados representativos destas duas classes (análise de dados multivariados populacionais, análise de dados multivariados espaciais, análise de dados univariados, estudo de campos eletromagnéticos a partir de resultados da análise de elementos finitos, simulação interativa visual de objetos animados dinamicamente e simulação interativa de sistemas discretos) é estabelecida uma classificação de entidades e atributos. Entidades são consideradas como pertencendo a três grandes classes: sistemas compostos por múltiplas entidades, objetos manufaturáveis e entidades ou fenômenos naturais, e são caracterizadas por atributos que podem ser analisados de acordo com sua natureza, o tipo dos valores que podem assumir, a natureza e dimensão do domínio no qual estão definidos. A seguir, são identificados os objetivos e tarefas no tratamento das entidades e atributos. Como objetivos considera-se observação de objetos num contexto, analise da estrutura dos objetos, analise das suas propriedades estáticas ou dinâmicas, analise comparativa de vários objetos e comunicação de informações. Tarefas básicas que servem a realização dos diversos objetivos são navegação, seleção, consulta, preparação e controle de processamento, anotação de textos e armazenamento de resultados. Esta classificação de tarefas permite a determinação das ferramentas básicas necessárias a realização tanto de analise exploratória como de simulação interativa, ambas visuais. E estabelecido um conjunto coordenado de ferramentas que permitem a realização das tarefas mencionadas com as diferentes classes de entidades. Essencial a estas classes de problemas é a representação visual a ser adotada como forma de transmissão de uma informação a respeito de uma entidade. Este aspecto é enfatizado neste trabalho; é estabelecida uma taxonomia para representações visuais, a saber, Ícones, gráficos e tabelas, diagramas e redes, modelos geométricos, mapas e seqüencias. de acordo com a informação fornecida e com o atendimento dos objetivos identificados anteriormente. Na seqüência, é proposta uma metodologia para a escolha de representações visuais baseada na classe das entidades sob estudo e nos objetivos do estudo (ou de uma face do estudo), numa primeira etapa, e na natureza dos atributos e dimensão de seu domínio, numa segunda etapa. A tese apresenta a abordagem baseada em ferramentas como paradigma básico de linguagem visual para analise exploratória e simulação interativa visual e estende o use da abordagem declarativa de visualização de programas a questão de visualização de dados. As classes de entidades reconhecidas ao longo do estudo são modeladas de acordo com a abordagem orientada a objetos: da mesma forma, o conjunto de ferramentas é organizado numa plataforma orientada a objetos. Esta plataforma é comparada, do ponto de vista funcional e considerando diferentes classes de usuários, com sistemas existentes. A estrutura proposta é, ainda, discutida como um modelo de referência para analise exploratória e simulação interativa visual. / Two related areas, visual exploratory analysis and visual interactive simulation, have been handled separately until now. This thesis gives an integrated approach to these two classes of problems, based on their relationships to visual languages, data visualization and program visualization. Case studies representing both areas like multivariate analysis of populational data, multivariate analysis of spatial data, analysis of univariate data, study of electromagnetic fields based on finite element analysis, dynamic graphical simulation and interactive visual discrete-event simulation, allow the construction of a taxonomy for entities and attributes. Entities are considered to belong to three classes: multiple-entity systems, manufacturable objects, and natural entities or phenomena. They are characterized by their attributes, which in turn are classified by nature, value types and nature and dimension of their definition domain. The goals and tasks in the study of entities and attributes are identified. Goals are observing an object in a context, analyzing an object structure, analyzing their static and dynamic properties, comparing objects or different states of objects and communicating information. Tasks are elementary procedures employed to achieve certain goals: navigation, selection, query, modification, processing control, text annotation and data storage. This classification of tasks determine the basic tools that a scientific user needs to visually explore data or conduct visual interactive simulation studies. These tools are organized as a set of interactive procedures that can be applied to visual representations of entities or their attributes. Visual representations are, of course, essential to visual exploratory analysis and visual interactive simulation, in order to precisely and adequately represent information about entities. This question is emphasized in this work. Based on the information conveyed by the several existing graphical representations as well as the goals established earlier, six classes of visual representations are considered: icons, graphs and tables, diagrams and networks, geometric models, maps, and sequences of these representations. A methodology for selecting the appropriate visual representation is then proposed, based firstly on the goals of the study and the classes of entities and attributes, and secondly on the nature and dimension of the attributes domain. This thesis presents a tool-centered approach as the paradigm for both visual exploratory analysis and visual interactive simulation. The thesis also extends the concept of declarative visualization employed for program visualization to scientific data visualization. The classes of entities identified in the case studies are modeled using the object-oriented approach; the set of tools defined here is also organized in an objectoriented framework. Our proposal is discussed as a reference model for visual exploratory analysis and visual interactive simulation.
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Objeto de aprendizagem como ferramenta de modelagem computacional exploratória aplicada ao ensino de física / Learning object as a modeling tool applied to exploratory computational physics educationVasconcelos, Francisco Herbert Lima January 2008 (has links)
VASCONCELOS, Francisco Herbert Lima. Objeto de aprendizagem como ferramenta de modelagem computacional exploratória aplicada ao ensino de física. 2008. 137 f. Dissertação (Mestrado em ciência da computação)- Universidade Federal do Ceará, Fortaleza-CE, 2008. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-11T16:06:38Z
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Previous issue date: 2008 / Researches in the field of Computers in Education demonstrate new possibilities in the development and learning of Physics concepts mediated by computer environments. Resources such as animation and interactive simulation allow the construction of concepts and new forms of mental representation of Physics models by students. Learning Objects (LO) are one of the most used computer learning environments. Just the use of such resources does not guarantee improvement in the learning process. The current study investigated how these objects can contribute to the understanding of Physics concepts and how students evaluate the use of such resources for the learning of Physics. The study was conducted at a public school in Fortaleza, Ceará – Brasil, with High School students while conducting computational modeling activitities. Data were collected through the application of an evaluation questionnaire developed for the research. The study concluded that students overcome some difficulties in understanding concepts of Physics and that before a new situation, which was purposely used in the computational environment for this research; some difficulties in the understanding of Physics concepts are detected. The results also indicate the feasibility of such methods as mediating elements in the teaching of Physics, especially in understanding of the photoelectric effect. / Pesquisas em Informática Educativa demonstram novas possibilidades no desenvolvimento e na aprendizagem de conceitos físicos mediados por ambientes computacionais. Recursos como a simulação e a animação interativa permitem aos alunos uma melhor construção de conceitos e novas formas de representação mental do modelo físico explorado. Dentre os ambientes computacionais desenvolvidos atualmente, destacam-se os Objetos de Aprendizagem (OA). Apenas a utilização de tais recursos não garante melhoria da qualidade no processo de aprendizagem. É necessário o desenvolvimento de metodologias de utilização destes recursos computacionais voltados para a Educação. O presente estudo investigou como OA podem contribuir para a compreensão de conceitos físicos e como os alunos avaliam sua utilização para a aprendizagem em Física. Foi realizado um experimento de campo em uma escola Pública de Fortaleza, Ceará – Brasil, com alunos do Ensino Médio durante a realização de atividades de modelagem computacional. Os dados foram coletados por meio de um dossiê avaliativo desenvolvido para esta pesquisa. O estudo concluiu que os alunos superam algumas dificuldades na compreensão de conceitos físicos e que diante de uma situação nova, que foi propositalmente explorada no ambiente computacional durante esta pesquisa, alguns problemas de concepção de conceitos em física são detectados. Os resultados do estudo apontam a viabilidade de tais metodologias como elementos mediadores no Ensino de Física, em especial na compreensão do Efeito fotoelétrico.
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Alga marinha vermelha Gracilaria cornea: novas perspectivas biotecnológicas e implicações neurofarmacológicas / Red seaweed Gracilaria cornea: new biotechnological perspectives and neuropharmacological implicationsSouza, Ricardo Basto January 2015 (has links)
SOUZA, Ricardo Basto. Alga marinha vermelha Gracilaria cornea: novas perspectivas biotecnológicas e implicações neurofarmacológicas. 2015. 264 f. Tese (Doutorado em Bioquímica)-Universidade Federal do Ceará, 2015. / Submitted by Vitor Campos (vitband@gmail.com) on 2016-09-05T23:02:44Z
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Previous issue date: 2015 / The red seaweed Gracilaria cornea is presented as a natural source still little explored, with potential bioactive, such as sulfated polysaccharides. Its sulfated polysaccharide, agaran-type (AS-Gc), wherein its structure and has anti-inflammatory and anti-nociceptive activity reported in the literature. However, methodological evaluations in their extraction process as well as new potential biological activities are still little reported in the literature. Thus, this study aimed to analyze a new reagent for isolation of AS-Gc and then evaluate its effects and possible mechanisms of action on valuation models psychotropic activity and neuroprotective in vivo and in vitro. Initially, we evaluated the method for isolating sulfated polysaccharides from algae G. cornea using isoamyl alcohol (IAA), in relation to the classical method using 1-hexadecylpyridinium chloride (CPC), considering qualitative and quantitative parameters (percentage yield analysis, physical-chemical and structural characterization) and evaluation of anticoagulant activity in vitro. For analysis of psychotropic effects of AS-Gc, we evaluated the acute administration of three doses (0.3, 3 or 30 mg / kg) and two routes of administration (per os-p.o. or subcutaneous-s.c.) in mice. Then, animals were assessed in physiological and neurobehavioural tests indicative of action level on nervous system and locomotive disorders and behaviors associated with anxiety, depression and sedation. To investigate the potential neuroprotective, we carried out the Parkinson's disease model in rats induced by intrastriatal injection of the neurotoxin 6-hydroxydopamine (6-OHDA), followed by a single dose of ASGC (15, 30 or 60 μg) via intrastriatal. After 14 days, locomotives, neurobehavioral and physiological analyzes were performed. After euthanasia, brain areas (hippocampus, the prefrontal cortex and striatum) were dissected and used to neurochemical and transcriptional analyzes. Additionally, we evaluated the antioxidant potential of AS-Gc in in vivo and in vitro. The results suggest that the classical method using CCP has greater efficiency and quality to obtain a AS-Gc, in relation to the use of AIA. However, the alternative method, using AIA showed potential biotechnological applications to obtain other molecules of commercial and scientific interest. AS-Gc (30 mg / kg, p.o. and s.c.) presented a safety pharmacology and promoted increased exploratory activity in mice. AS-Gc (60 μg, intraestrital) promoted a neuroprotective activity in vivo and in vitro through mitochondrial protection, reduced glutathione induction, lipid peroxidation and nitrite levels reduction, and modulation of transcriptional pathways in the striatum of rats and returning locomotive and renal activities to normal conditions. Thus, this study show new perspectives for biotechnological obtaining chemically different molecules seaweed and suggests new neuropharmacological implications for the use of sulfated agaran from G. cornea. Furthermore, the AS-Gc present therapeutic potential against neurodegenerative disorders. / A alga marinha vermelha Gracilaria cornea apresenta-se como uma fonte natural ainda pouco explorada, com bioativos em potencial, como os polissacarídeos sulfatados. Seu polissacarídeo sulfatado, do tipo agarana (AS-Gc), possui sua estrutura caracterizada e atividade anti-inflamatória e anti-nociceptiva reportada na literatura. Entretanto, avaliações metodológicas no seu processo de extração, bem como novas atividades biológicas em potencial ainda são pouco reportadas na literatura. Deste modo, o presente estudo objetivou analisar um novo reagente para o isolamento de AS-Gc e, posteriormente, avaliar seus efeitos e possíveis mecanismos de ação em modelos de avaliação de atividades psicotrópicas e neuroprotetoras in vivo e in vitro. Inicialmente, realizou-se uma avaliação da metodologia de isolamento de polissacarídeos sulfatados isolados da alga G. cornea utilizando álcool isoamílico (AIA), em relação ao método clássico utilizando cloreto de 1-hexadecilpiridinio (CCP), considerando parâmetros qualitativos e quantitativos (análises de percentual de rendimento, de caracterização físico-química e estrutural) e de uma avaliação de atividade anticoagulante in vitro. Para análise de efeitos psicotrópicos de AS-Gc, avaliou-se a administração aguda de três doses (0,3; 3 ou 30 mg/Kg) e duas vias de administração (oral-v.o. ou subcutânea-s.c.) em camundongos. Em seguida, os animais foram submetidos a avaliação fisiológica e a ensaios neurocomportamentais, indicativo de nível de ação no sistema nervoso e relacionados a alterações locomotoras e de comportamentos associados de ansiedade, depressão e sedação. Para a investigação do potencial neuroprotetor, realizou-se o modelo de indução de doença de Parkinson em ratos com injeção intraestriatal da neurotoxina 6-hidroxidopamina (6-OHDA), seguido por única administração de AS-Gc (15, 30 ou 60 µg), via intraestriatal. Após 14 dias, os animais foram submetidos a análises locomotoras, neurocomportamentais e fisiológicas. Após eutanásia, áreas cerebrais (hipocampo, córtex pré-frontal e corpos estriados) foram dissecadas e utilizadas para análises neuroquímicas e transcricionais. Adicionalmente, avaliou-se o potencial antioxidante de AS-Gc em ensaios in vivo e in vitro. Os resultados sugerem que o método clássico, utilizando CCP, apresenta maior eficiência e qualidade para obtenção de AS-Gc, em relação ao uso de AIA. Entretanto, o método alternativo, utilizando AIA, demonstrou potenciais aplicações biotecnológicas para obtenção de outras moléculas de interesse comercial e científico. AS-Gc (30 mg/kg, v.o. e s.c.) apresentou uma segurança farmacológica e promoveu o aumento da atividade exploratória em camundongos. AS-Gc (60 µg, intraestrital) promoveu uma atividade neuroprotetora in vivo e in vitro, através de proteção mitocondrial, indução de glutationa reduzida, redução dos níveis de peroxidação lipídica e de nitrito, e modulação de vias transcricionais em corpo estriado de ratos, retornando atividades locomotoras e renais a condições normais. Desta forma, o presente estudo apresenta novas perspectivas biotecnológicas para obtenção de moléculas quimicamente diferentes de algas marinhas e sugere novas implicações neurofarmacológicas para o uso da agarana sulfatada de G. cornea. Adicionalmente, AS-Gc apresenta potencial terapêutico contra desordens neurodegenerativas.
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