A cafeína como agente modulador do ciclo atividade-repouso e memória em saguis (Callithrix jacchus)

Caffeine is the most consumed psychostimulant, with effects on attention, memory, and arousal. But when this substance is ingested near to bedtime there is a decrease on sleep, interfering on mnemonic processes. So, our ain was to investigate how the caffeine ingested near to sleep onset acts on sleep and memory in marmosets. We used 16 adult marmosets, single housed, in a 12:12h light-dark cycle. For registering locomotor activity were used two kinds of sensors. The gyroscope sensor registers activity each 30 sec and detects motion with good accuracy. Because of this we used this sensor for detecting nocturnal activity. The second sensor was based on infrared and accumulates activity each 5 min and it’s not able to detect nocturnal activity, just diurnal activity. We also used camera for registering Rest phase of one marmoset. For the cognitive task, the animals needed to learn a rewarded context (CR) when compared to a non-rewarded context CNR). This experiment comprises 5 phases: 1) Two days of habituation to apparatus; 2)Training for 8 days; 3) oral administration of caffeine (10 mg/kg) or placebo administration ±1h before sleep onset, for 8 days, with marmosets receiving placebo or caffeine; 4) retraining to apparatus and after that, placebo administration (placebo group-GP), or caffeine administration (with continuous group-GC and acute groupGA); 5) Test, for evaluating learning to CR. The sessions were filmed and each one had 8 min of duration. At 7 am started the habituation, training and test sessions, and at 3:15 pm started retraining. The results for gyroscope sensor showed that there was coincidence of 68,57% with nocturnal register of the cameras. Then, the gyroscope sensors detected nocturnal activity for all experimental groups Moreover, when compared sensor gyroscope with sensor based on infrared, was observed that both sensor presented similarity on patterns of activity curve. When we observed the effects of caffeine on Activity-Rest Cycle in GP, GA and GC, is possible to see that that gyroscope sensors and based on infrared presented only intra group differences. As behavioral results, the marmosets learned to discriminate CR when compared to CNR. Moreover, GP presented deficits on memory recall during the test, and GA increased the memory recall, when both were compared to GP. We concluded that the marmosets were able to learning the cognitive task and that the caffeine ingested near to sleep onset acts modulating memory in these animals. Moreover the gyroscope sensor can be used as alternative tool for investigating nocturnal activity. Then, the utilization of this non-invasive device allows marmosets exhibit their behavior within the laboratory conditions as natural as possible.

Avaliação do potencial das fibras de Ceiba Pentandra (Kapok) e Calotropis Procera como adsorventes de petróleo

On the basis of human evolution and the population increase was necessary, the emergence of new sources of energy, the development of new products and technologies. One such product, object of the industry revolution and of great importance to the development of humanity is the oil, a substance composed primarily of hydrocarbons which give rise to several other products as fuels, lubricants, polymers, solvents, cooking gas, asphalt for roads, fertilizers, medicines, paints, among other. However, mishandling this product may cause leaks and spills that generate huge damages to the environment and the economy. Soon, with the purpose of contributing to decrease is problematic, in this master's work was carried out an intensive search of the possible potential of the fibers of Ceiba pentandra (L.) "Kapok" and Calotropis Procera as bioadsorbents of petroleum in water. The choice of these fibers is due to surface properties such as oleophylics and hydrophobic, their buoyancy and yet, being biodegradable natural polymers derived from the Brazilian Northeast. This research was used experimental planning with response surface methodology (RSM) with the software Design Expert. The results were statistically efficient, obtaining a R2= 0.9995 for Calotropis Procera and a R2= 0.9993 for Kapok. And that, both fibers showed adsorption efficiency, removing more than 80% petroleum in water static and dynamic state.

Degradação fotocatalítica oxidativa do fenol utilizando carvão obtido da pirólise de diferentes biomassas

The modern industrial progress has been contaminating water with phenolic compounds. These are toxic and carcinogenic substances and it is essential to reduce its concentration in water to a tolerable one, determined by CONAMA, in order to protect the living organisms. In this context, this work focuses on the treatment and characterization of catalysts derived from the bio-coal, by-product of biomass pyrolysis (avelós and wood dust) as well as its evaluation in the phenol photocatalytic degradation reaction. Assays were carried out in a slurry bed reactor, which enables instantaneous measurements of temperature, pH and dissolved oxygen. The experiments were performed in the following operating conditions: temperature of 50 °C, oxygen flow equals to 410 mL min-1 , volume of reagent solution equals to 3.2 L, 400 W UV lamp, at 1 atm pressure, with a 2 hours run. The parameters evaluated were the pH (3.0, 6.9 and 10.7), initial concentration of commercial phenol (250, 500 and 1000 ppm), catalyst concentration (0, 1, 2, and 3 g L-1 ), nature of the catalyst (activated avelós carbon washed with dichloromethane, CAADCM, and CMADCM, activated dust wood carbon washed with dichloromethane). The results of XRF, XRD and BET confirmed the presence of iron and potassium in satisfactory amounts to the CAADCM catalyst and on a reduced amount to CMADCM catalyst, and also the surface area increase of the materials after a chemical and physical activation. The phenol degradation curves indicate that pH has a significant effect on the phenol conversion, showing better results for lowers pH. The optimum concentration of catalyst is observed equals to 1 g L-1 , and the increase of the initial phenol concentration exerts a negative influence in the reaction execution. It was also observed positive effect of the presence of iron and potassium in the catalyst structure: betters conversions were observed for tests conducted with the catalyst CAADCM compared to CMADCM catalyst under the same conditions. The higher conversion was achieved for the test carried out at acid pH (3.0) with an initial concentration of phenol at 250 ppm catalyst in the presence of CAADCM at 1 g L-1 . The liquid samples taken every 15 minutes were analyzed by liquid chromatography identifying and quantifying hydroquinone, p-benzoquinone, catechol and maleic acid. Finally, a reaction mechanism is proposed, cogitating the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. Applying the model of Langmuir-Hinshelwood along with a mass balance it was obtained a system of differential equations that were solved using the Runge-Kutta 4th order method associated with a optimization routine called SWARM (particle swarm) aiming to minimize the least square objective function for obtaining the kinetic and adsorption parameters. Related to the kinetic rate constant, it was obtained a magnitude of 10-3 for the phenol degradation, 10-4 to 10-2 for forming the acids, 10-6 to 10-9 for the mineralization of quinones (hydroquinone, p-benzoquinone and catechol), 10-3 to 10-2 for the mineralization of acids.

Citoarquitetura e imunoistoquímica para tirosinahidroxilase dos núcleos dopaminérgicos mesencefálicos do morcego (Artibeus planirostris)

The 3-Hidroxytyramine/dopamine (DA) is a monoamine of catecholamine family and isthe precursor substance synthesis of noradrenaline and adrenaline, having the enzymeTyrosine Hydroxylase (TH) as this regulatory process. In addition, the DA has theability to act as a neurotransmitter in the Central Nervous System - SNC, being themain neurotransmitter of brain nuclei, namely of A8 to A16. The nuclei of the midbrainthat express DA are the Retrorubral Field (RRF, A8), the Substantia Nigra parsCompacta (SNc, A9) and the Ventral Tegmental Area (VTA, A10). Such nuclei areinvolved in complex three circuitry that are the mesostriatal, mesolimbic andmesocotical and are directly related with several behavioral manifestations as motricitycontrol, reward signaling in behavioral learning, motivation and pathologicalconditions, such as Parkinson's Disease and schizophrenia. Interestingly, many of themorphological bases of these neural disturbance remain unknown. Considering therelevance of mesencephalic dopaminergic nuclei, the aim of this research is tocharacterize morphologically the dopaminergic nuclei (clusters A8, A9 and A10) of themidbrain of the bat (Artibeus planirostris). The Artibeus planirostris is a common bat inRio Grande do Norte. Ten animals were used in this research. The animals wereanesthetized, perfused, and the brain was removed from the skull. After dehydration insucrose, the brain was underwent microtomy. Saggital and coronal sections wereobtained and collected in six separate series. The series were Nissl-stained to identifythe cytoarchitectonic boundaries and the other series were subjected toimmunohistochemistry for TH. After cytoarchitectonic analysis and TH+ cellsidentification was possible to establish the anatomical boundaries of the nuclei, as wellas the subdivisions of three of the midbrain dopaminergic nuclei. The SNc is the mostrostral nucleus observed in the midbrain and is identified throughout the rostrocaudalextension of the midbrain. The VTA neurons were seen immediately caudal to the SNcappearance. The RRF neurons were observed just in the caudal levels of the midbrain.The SNc in Artibeus planirostris shows a particular feature, the tail of the SNc. The tailhave been described just in two other studied species. The present work shows aparticular variation in the organizational morphology of the SNc in the artibeus andcontribute to understand the phylogenetic routes by which the dopaminergic system hasevolved.

Organização nuclear do sistema serotonérgico no encéfalo de morcegos Artibeus planirostris

Serotonin or 5-hydroxytryptamine (5-HT) is a substance found in many tissues of the body, including the nervous system acting as a neurotransmitter. Within the neuro-axis, the location of the majority of the 5-HT neurons is superimposed with raphe nuclei of the brain stem, in the median line or its vicinity, so that neuronal 5-HT can be considered a marker of the raphe nuclei. Serotonergic neurons are projected to almost all areas of the brain. Studies show the participation of serotonin in regulating the temperature, feeding behavior, sexual behavior, biological rhythms, sleep, locomotor function, learning, among others. The anatomy of these groups has been revised in many species, including mouse, rabbit, cat and primates, but never before in a bat species from South America. This study aimed to characterize the serotonergic clusters in the brain of the bat Artibeus planirostris through immunohistochemistry for serotonin. Seven adult bat males of Artibeus planirostris species (Microchiroptera, Mammalia) were used in this study. The animals were anesthetized, transcardially perfused and their brains were removed. Coronal sections of the frozen brain of bats were obtained in sliding microtome and subjected to immunohistochemistry for 5-HT. Delimit the caudal linear (CLi), dorsal (DR), median (MnR), paramedian (PMnR), pontine (PNR), magnus (MgR), pallidus (RPA) and obscurus (ROb) raphe nucleus, in addition to the groups B9 and rostral and caudal ventrolateral (RVL/CVL). The serotonergic groups of this kind of cheiroptera present morphology and cytoarchitecture relatively similar to that described in rodents and primates, confirming the phylogenetic stability of these cell clusters.

Avaliação do efeito do liraglutida nos tecidos muscular e adiposo e nos parâmetros bioquímicos em camundongos Swiss submetidos à dieta de cafeteria e a atividade física

Obesity is a chronic metabolic disease characterized by adipose tissue formation excess leading to an increase in body fat mass, of multifactorial origin, produced mainly by poor eating habits combined with a sedentary lifestyle. Data consider obesity as a serious disease that affects the world's population, ranking fifth in death rates. Faced with this situation, individuals seek, increasingly, means to lose weight with less physical effort and food. In 2009 and 2010 the drug liraglutide was lauched in order to reduce weight in individuals with diabetes mellitus type 2, thus avoiding the emergence of other diseases. The aggravating factor is that obese nondiabetic individuals are making use of this substance, even if its use is not authorized by ANVISA (Brazilian Health Surveillance Agency). Thus the objective of this research is to evaluate the effect of liraglutide for muscle or fat tissues and biochemical parameters in Swiss mice submitted to cafeteria diet and physical activity. The study was approved by the Ethics Committee on Animal Use - CEUA (nº003 Protocol / 2014). For this study 74 animals (Swiss mice) were used, divided as follows: in the initial phase of this study, we carried out a pilot study (n = 10) divided into a control group (PCON) (n = 5) and cafeteria group (PCAF) (n = 5), in order to evaluate a cafeteria diet which was both attractive to the animals and that could provide an increase in adipose tissue. After the induction of the diet, animals were euthanized and as a result, the animals in the PCAF group showed an intra-abdominal adiposity 0.74 ± 0.05 g, taken as the parameter for increasing fat in animals. Subsequently the study base was conducted for this research where animals were used (n = 64) divided into 2 groups: the Cafeteria Study Base Group (EBCAF) divided as follows: cafeteria + exercise + liraglutide (CEL) (n = 8), cafeteria + exercise + saline (CES) (n = 8), cafeteria + liraglutide (CL) (n = 8) and cafeteria + saline (CS) (n = 8). The Chow Study Base group (EBR) was divided into: exercise + liraglutide (EL) (n = 8), exercise + saline + (ES) (n = 8), liraglutide (L) (n = 8) and saline solution (SS) (n = 8). All animals went through the submission process to the cafeteria diet, followed by exercise protocol through swimming and treatment with the test substance intraperitoneally (200 mg / mL / kg). After the treatments, the animals were euthanized and had the following parameters evaluated: the muscle tissue mass, adipose tissue mass and biochemical parameters. It was observed that the processing done with the exercise-associated liraglutide reduced adipose tissue mass significantly (0.32 ± 0.05 g) compared to the saline group (0.53 ± 0.07 g). There were no changes in the muscle tissue of the group which was treated and exercised (1.39 ± 0.03 g) compared to the saline group (1.33 ± 0.03 g). Regarding biochemical parameters it was evident that there were changes in these parameters. Interesting to note that, although blood glucose values have been changed, the animals did not become diabetic. Thus, it appears that physical activity together with liraglutide is eficcient to the loss of intraabdominal adipose tissue and the maintenance of lean body mass thereby generating a satisfactory result in the pursuit of quality of life and disease prevention.

Avaliação do efeito do liraglutida nos tecidos muscular e adiposo e nos parâmetros bioquímicos em camundongos Swiss submetidos à dieta de cafeteria e a atividade física

Obesity is a chronic metabolic disease characterized by adipose tissue formation excess leading to an increase in body fat mass, of multifactorial origin, produced mainly by poor eating habits combined with a sedentary lifestyle. Data consider obesity as a serious disease that affects the world's population, ranking fifth in death rates. Faced with this situation, individuals seek, increasingly, means to lose weight with less physical effort and food. In 2009 and 2010 the drug liraglutide was lauched in order to reduce weight in individuals with diabetes mellitus type 2, thus avoiding the emergence of other diseases. The aggravating factor is that obese nondiabetic individuals are making use of this substance, even if its use is not authorized by ANVISA (Brazilian Health Surveillance Agency). Thus the objective of this research is to evaluate the effect of liraglutide for muscle or fat tissues and biochemical parameters in Swiss mice submitted to cafeteria diet and physical activity. The study was approved by the Ethics Committee on Animal Use - CEUA (nº003 Protocol / 2014). For this study 74 animals (Swiss mice) were used, divided as follows: in the initial phase of this study, we carried out a pilot study (n = 10) divided into a control group (PCON) (n = 5) and cafeteria group (PCAF) (n = 5), in order to evaluate a cafeteria diet which was both attractive to the animals and that could provide an increase in adipose tissue. After the induction of the diet, animals were euthanized and as a result, the animals in the PCAF group showed an intra-abdominal adiposity 0.74 ± 0.05 g, taken as the parameter for increasing fat in animals. Subsequently the study base was conducted for this research where animals were used (n = 64) divided into 2 groups: the Cafeteria Study Base Group (EBCAF) divided as follows: cafeteria + exercise + liraglutide (CEL) (n = 8), cafeteria + exercise + saline (CES) (n = 8), cafeteria + liraglutide (CL) (n = 8) and cafeteria + saline (CS) (n = 8). The Chow Study Base group (EBR) was divided into: exercise + liraglutide (EL) (n = 8), exercise + saline + (ES) (n = 8), liraglutide (L) (n = 8) and saline solution (SS) (n = 8). All animals went through the submission process to the cafeteria diet, followed by exercise protocol through swimming and treatment with the test substance intraperitoneally (200 mg / mL / kg). After the treatments, the animals were euthanized and had the following parameters evaluated: the muscle tissue mass, adipose tissue mass and biochemical parameters. It was observed that the processing done with the exercise-associated liraglutide reduced adipose tissue mass significantly (0.32 ± 0.05 g) compared to the saline group (0.53 ± 0.07 g). There were no changes in the muscle tissue of the group which was treated and exercised (1.39 ± 0.03 g) compared to the saline group (1.33 ± 0.03 g). Regarding biochemical parameters it was evident that there were changes in these parameters. Interesting to note that, although blood glucose values have been changed, the animals did not become diabetic. Thus, it appears that physical activity together with liraglutide is eficcient to the loss of intraabdominal adipose tissue and the maintenance of lean body mass thereby generating a satisfactory result in the pursuit of quality of life and disease prevention.

A compreensão de reação química como um sistema complexo a partir da discussão dos erros e dificuldades de aprendizagem de estudantes do ensino médio

The study of chemical reactions is among the most important contents to the understanding of Chemistry discipline in basic education. However, there are still few studies about chemical reactions as a complex system because, generally, this content is presented in textbooks, taught and even researched in a fragmented form. The thesis here presented aims to investigate, identify and characterize the mistakes and learning difficulties of the students about chemical reactions as a complex system, using for that purpose the analysis of the answers of 126 exams of candidates for the bachelor’s degree in Chemistry Teaching on the entrance exam for the Federal University of Rio Grande do Norte (UFRN). The mistakes and learning difficulties about the parameters ΔG°, Kp, Ea and of the calculation of the amount of substance in a chemical reaction have been identified, as well as the levels of development of the ability to interpret the chemical reaction as a system. The main theoretical source of this study is structured based on the mistakes and learning difficulties (NÚÑEZ, RAMALHO, 2012), of the chemical reactions as complex systems (NÚÑEZ, 1994; RESHETOVA, 1988; SANDERSON, 1968). As methodology, it was prioritized the analysis of the answers to the exams and the interview with the teachers. The results showed typical mistakes in the study of this subject, especially low levels and skill development. No student was able to integrate the different aspects in the systemic understanding of the chemical reaction. From the interviews with Chemistry teachers from High School, it was determined the reasons the teachers assign to those mistakes and learning difficulties. The interviews revealed that the teachers do not work in the perspective of integration of the contents which leads the students to present difficulties and make mistakes related to the content previously mentioned. The study presents a proposal for the organization of the contents of Chemistry discipline for High School as a possibility of a dialectic systemic integration of contents, understanding that this systematic vision, leads to important contributions to the development of the theoretical thinking of the students. We can mention as one of the conclusions of this study, the fact that the non-systemic organization of contents do not favor this kind of thinking in students.

Mecanismos de neurotoxicidade induzidos pela Dopamina e pela 6–OH-dopamina num modelo celular humano: efeito da presença de extratos de algas com elevada capacidade antioxidante

O aumento da esperança média de vida tem elevado a prevalência de doenças neurodegenerativas, como é o caso da doença de Parkinson. Nos últimos anos a procura de novas soluções terapêuticas, assim como a minimização dos efeitos dos tratamentos atualmente utilizados tem promovido a procura de novas soluções. Deste modo, o objetivo deste trabalho consistiu no estudo dos mecanismos moleculares de neurotoxicidade induzidos pela dopamina (DA) e 6-hidroxidopamina (6-OHDA) num modelo celular do neuroblastoma humano (SH-SY5Y), bem como na avaliação do potencial neuroprotetor de extratos de algas com elevada capacidade antioxidante. O efeito neurotóxico da DA e 6-OHDA, assim como o efeito protetor dos extratos das algas com maior atividade antioxidante (Sargassum muticum, Saccorhiza polyschides, Padina pavonica, Codium tomentosum, Ulva compressa) foi avaliado através da viabilidade celular das células SH-SY5Y utilizando o método de MTT. De modo a compreender os efeitos induzidos na viabilidade celular pela DA e 6-OHDA procedeu-se ao estudo da atividade da caspase-3, alterações do potencial mitocondrial e quantificação de H2O2. Os resultados demonstraram um claro efeito dependente da concentração da DA (30-3000μM) e 6-OHDA (10-1000μM) na viabilidade celular das células SH-SY5Y, bem como do tempo de exposição (6-48h). No que diz respeito a prevenção do efeito neurotóxico da DA (1000μM (56,41±5,05% de células viáveis); 24h) e 6-OHDA (100μM (66,76±3,24% de células viáveis);24h) pelos extratos das algas (1mg/mL; 24h) verificou-se que os extratos que apresentaram um efeito preventivo mais marcado pertencem as algas Sargassum muticum (82,37±6,41% de células viáveis e 115,8±8,53% de células viáveis, após tratamento com DA e 6-OHDA, respetivamente), Saccorhiza polyschides (89,26±8,62% de células viáveis e 106,51±4,26% de células viáveis, após tratamento com DA e 6-OHDA, respetivamente) e Codium tomentosum (81,28±3,68% de células viáveis e 103,17±7,25% de células viáveis, após tratamento com DA e 6-OHDA, respetivamente). A morte celular induzida pela DA e pela 6-OHDA foi acompanhada pelo aumento da atividade da caspase-3 quando comparado com o controlo (DA - 66,46±1,49fluorescência (u.a)/mg de proteína/minuto; 6-OHDA - 22,56±1,71fluorescência (u.a)/mg de proteína/minuto; controlo – 4,8 ±0,48fluorescência (u.a)/mg de proteína/minuto), pela presença de elevadas quantidades de peróxido de hidrogénio (H2O2) (363,81±28,58 % do controlo e 214,26 ± 8,46 % do controlo, após tratamento com DA e 6-OHDA, respetivamente) e pela despolarização da membrana mitocondrial (162,3±2,34 % do controlo e 144,7±2,87 % do controlo, após tratamento com DA e 6-OHDA, respetivamente). Por sua vez, durante o tratamento com extratos das algas (1mg/mL) na presença de DA e 6-OHDA verificou-se uma inibição da atividade da caspase-3 induzida pelas algas Sargassum muticum (2,53±2,49fluorescência (u.a)/mg de proteína/minuto e 4,52±1,36 fluorescência (u.a)/mg de proteína/minuto, após tratamento com DA e 6-OHDA, respetivamente), Saccorhiza polyschides (4,71±0,70fluorescência (u.a.)/mg de proteína/minuto e 2,73±1,11 fluorescência (u.a.)/mg de proteína/minuto, após tratamento com DA e 6-OHDA, respetivamente) e Codium tomentosum (17,05±1,72fluorescência (u.a.)/mg de proteína/minuto e 2,58±1,77fluorescência (u.a)/mg de proteína/minuto, após tratamento com DA e 6-OHDA, respetivamente). De igual modo verificou-se uma diminuição da produção de H2O2 pelas células SH-SY5Y na presença dos extratos das algas Sargassum muticum (132,58 ± 10,68% controlo), Saccorhiza polyschides (150,54 ± 23,54% controlo) e Codium tomentosum (54,074 ± 6,66% do controlo), quando expostas a 6-OHDA, contudo não se verificou o mesmo efeito na presença de DA. Relativamente ao potencial mitocondrial observou-se uma inibição da despolarização mitocondrial induzida pela DA e 6-OHDA nas células SH-SY5Y pela presença dos extratos das algas Sargassum muticum (135,7±2,97% controlo e 49,3±1,17% controlo, após tratamento com DA e 6-OHDA, respetivamente), Saccorhiza polyschides (126,7±5,46% controlo e 94,3±1,70% controlo, após tratamento com DA e 6-OHDA, respetivamente). Os resultados obtidos demonstraram o potencial citoprotetor dos extratos de algas sobre efeitos neurotóxicos induzidos pela DA e 6-OHDA no modelo celular SH-SY5Y. O efeito protetor é mediado pela diminuição da condição de stress oxidativo, com redução da produção de H2O2, diminuição da atividade da caspase-3 e prevenção da alteração do potencial mitocondrial induzido pela DA e 6-OHDA. Conclui-se que os extratos de algas produzem moléculas bioativas com elevado potencial antioxidante, podendo ser uma fonte promissora de novos compostos neuroprotetores com aplicação terapêutica para doenças neurodegenerativas como a doença de Parkinson.

Representações Sociais da Cannabis no Concelho de Góis

A cannabis permanece como a substância ilícita mais consumida no mundo. Defendida por uns e “diabolizada” por outros, constitui uma das substâncias psicoactivas mais polémicas. Alguns autores destacaram já, a importância do estudo das representações sociais das substâncias psicoactivas. No entanto, desconhecem-se investigações que abordem a representação social desta substância num espaço rural. São objectivos deste estudo: 1) conhecer as representações sociais da cannabis no que diz respeito à substância, ao consumidor e ao contexto da utilização, 2) identificar as diferenças existentes entre utilizadores e não utilizadores desta substância da amostra em estudo. Para concretizar estes objectivos, foi realizado um estudo qualitativo que recorreu a uma dupla abordagem etno-metodológica e fenomenológica. Foram realizadas 30 entrevistas a indivíduos residentes nas duas maiores freguesias do concelho de Góis que, depois de transcritas, foram objecto de análise de conteúdo. No espaço rural considerado, a cannabis é maioritariamente representada como uma “droga”, indutora de uma sensação de mal-estar e causadora de dependência. Para os participantes o utilizador é percebido como detentor de características de personalidade negativas, que o induzem ao consumo. Relativamente ao eixo espacial, o espaço rural, e mais especificamente o concelho de Góis é representado como local de consumo e de produção da cannabis herbácea. Há uma distinção clara entre a representação social dos participantes que não utilizam a substância e os que utilizam. O último grupo representa-a como uma “droga leve”, e mostra-se esclarecido sobre as possíveis consequências da sua utilização. Neste grupo é ainda evidente a valorização da cannabis herbácea, em detrimento dos seus derivados. /

Programa de prevenção indicada em jovens consumidores de cannabis

A cannabis é a substância ilícita mais consumida pela população jovem (EMCDDA, 2015). Devido ao aumento das prevalências de consumo desta substância, tem-se verificado um aumento do número de indivíduos que recorrem ou são encaminhados para os serviços de saúde tendo a cannabis como droga principal. Por este motivo, temos assistido a uma necessidade cada vez maior de se realizarem intervenções preventivas que proporcionem conhecimentos e competências que ajudem a lidar com o risco associado ao consumo de substâncias psicoativas (SICAD, 2013a). O principal objetivo da presente dissertação é avaliar a eficácia de um programa de prevenção indicada aplicado num grupo de jovens consumidores de cannabis através de uma avaliação pré e pós-intervenção. A amostra foi constituída por 10 jovens consumidores de cannabis, pertencentes à consulta de prevenção indicada do Centro de Respostas Integradas de Aveiro. A intervenção em grupo implementada foi avaliada através da aplicação dos seguintes instrumentos: ASSIST, AUDIT e SCL-90-R e a análise de dados foi realizada através do SPSS – Versão 19.0. Não foram encontradas diferenças estatisticamente significativas ao nível da sintomatologia psicopatológica e de consumo entre as duas fases de avaliação do grupo de prevenção indicada. Contudo, observaram-se melhorias significativas no grupo de controlo ao nível de algumas subescalas psicopatológicas. Conclui-se que a intervenção individual foi mais eficaz do que a intervenção em grupo. Os resultados obtidos colocam em causa a pertinência de se realizarem intervenções em grupo neste tipo de populações.

Familial amyloid polyneuropathy: TTR sequencing and "in silico" analysis

Familial amyloid polyneuropathy (FAP) or paramiloidosis is an autosomal dominant neurodegenerative disease with onset on adult age that is characterized by mutated protein deposition in the form of amyloid substance. FAP is due to a point alteration in the transthyretin (TTR) gene and until now more than 100 amyloidogenic mutations have been described in TTR gene. FAP shows a wide variation in age-at-onset (AO) (19-82 years, in Portuguese cases) and the V30M mutation often runs through several generation of asymptomatic carriers, before expressing in a proband, but the protective effect disappear in a single generation, with offspring of late-onset cases having early onset. V30M mutation does not explain alone the symptoms and AO variability of the disease observed in the same family. Our aim in this study was to identify genetic factors associated with AO variability and reduced penetrance which can have important clinical implications. To accomplish this we genotyped 230 individuals, using a directautomated sequencing approach in order to identify possible genetic modifiers within the TTR locus. After genotyping, we assessed a putative association of the SNPs found with AO and an intensive in silico analysis was performed in order to understand a possible regulation of gene expression. Although we did not find any significant association between SNPs and AO, we found very interesting and unreported results in the in silico analysis since we observed some alterations in the mechanism of splicing, transcription factors binding and miRNAs binding. All of these mechanisms when altered can lead to dysregulation of gene expression, which can have an impact in AO and phenotypic variability. These putative mechanisms of regulation of gene expression within the TTR gene could be used in the future as potential therapeutical targets, and could improve genetic counselling and follow-up of mutation carriers.

Reconstrução da papila interdentária com ácido hialurónico

Introdução: Os procedimentos de reconstrução da papila interdentária revestem-se de uma tal complexidade técnica que representam um verdadeiro desafio na área da Periodontia. O ácido hialurónico é uma substância que vem sendo cada vez mais estudada, tanto no tratamento de diversas patologias, como em situações de melhoria estética. Muito recentemente, a reconstrução mediante a injeção de ácido hialurónico na papila interdentária vem sendo desenvolvida como uma promissora alternativa às técnicas cirúrgicas de reconstrução da papila interdentária. Objectivo: O objetivo deste trabalho de revisão bibliográfica foi avaliar o potencial da utilização do ácido hialurónico na reconstrução da papila interdentária. Materiais e Métodos: Foi realizada uma pesquisa bibliográfica, entre outubro de 2013 e junho de 2014, nas bases de dados MEDLINE, B-on, Scopus e Google Académico. Dessa pesquisa resultaram 48 artigos. Foram ainda consultados dois casos clínicos gentilmente cedidos pela empresa CPMPHARMA. Resultados: Os resultados dos escassos estudos disponíveis até à data permitem afirmar que a utilização de ácido hialurónico na reconstrução da papila interdentária constitui uma importante alternativa com vantagens significativas. Conclusões: São necessários mais estudos para confirmar os resultados encontrados.

Micotoxinas – contributos do projeto Mycomix e perspetivas futuras

As micotoxinas são metabolitos secundários produzidos por várias espécies de fungos, e que podem contaminar os alimentos nas diferentes fases de produção, colheita, armazenagem ou processamento. Além de constituir um problema económico e de segurança alimentar, a contaminação de alimentos com micotoxinas é essencialmente um problema de saúde pública, dado que estes compostos podem provocar efeitos graves na saúde humana e animal, estando classificadas pela Agência Internacional de Investigação em Cancro (IARC) como carcinogénicos dos grupos 1, 2B e 3. O projecto Mycomix PTDC/DTP/FTO/0417-2012 (2013-2015), que consistiu num estudo exploratório dos efeitos tóxicos de misturas de micotoxinas em alimentos para crianças revelou a presença de múltiplas micotoxinas em simultâneo em alimentos à base de cereais, indicando que as crianças poderão estar expostas a micotoxinas através da alimentação. No âmbito do projecto Mycomix foi avaliada a exposição de crianças a micotoxinas através da aplicação de diários alimentares para determinação do consumo alimentar. Como alternativa às metodologias de avaliação de risco baseadas no consumo alimentar, a Agência Europeia de Segurança Alimentar (EFSA) recomendou a implementação de metodologias harmonizadas de biomonitorização humana, que é uma metodologia que permite avaliar a exposição do Homem a substâncias naturais e sintéticas do meio ambiente, baseando-se na análise direta de biomarcadores em tecidos e fluidos. É por isso o único método para avaliar diretamente a exposição a determinada substância, a sua magnitude, e a sua variação ao longo do tempo.

Compreensão da reação de precipitação do iodeto de chumbo entre os níveis de análise macro e micro no ensino da química

O estudo apresentado teve como objetivos planificar e implementar e analisar uma proposta didática alternativa para a abordagem dos níveis macroscópico, simbólico e sub-microscópico, indispensáveis para a compreensão das reações químicas, salientando-se o facto de não se explorar, nos manuais e na prática, todo o potencial de uma reação química muito usual. A proposta utiliza uma diferente abordagem da tradicional reação de precipitação do iodeto de chumbo, centrada em questões-problema: “Ocorreu uma reação química?” e “Será possível dissolver o precipitado?”. A metodologia foi qualitativa e centrou-se na investigação-ação colaborativa. Perante as questões problema, os alunos fizeram previsões, sugeriram e realizaram procedimentos experimentais de carácter investigativo para as testar e fundamentaram as respostas através da comunicação oral e da elaboração de esquemas pictóricos (livremente), estes últimos, para ilustrar o nível sub-microscópico. Analisaram-se conjuntamente os esquemas e os dados da observação direta. Os resultados evidenciam que os alunos: identificam a ocorrência da reação química sensorialmente (visualização do aparecimento de uma substância colorida após a junção de duas soluções incolores - nível macroscópico), representam a reação química utilizando a simbologia química (nível simbólico) mas apresentam algumas dificuldades na interpretação sub-microscópica.