Dissertations / Theses on the topic 'Sex role – Brazil'

The thesis aims to provide a first ethnographic description of the Menkü of Central Brazil by focussing on their non-hierarchical gender-complementarity as it realises itself in relationships of production and reproduction. The first part of the thesis comprises of an introduction to the group from a historical point of view by providing a description of the Menkü's historical experiences during this century. This is followed by a description of the settlement, and the social spaces it encompasses. The second part focusses on the creation of real food by firstly elaborating social and physical aspects of material production. Secondly, it explores the metaphysical aspects of production and reproduction by uncovering the relationships human beings engage in with the world of masters of the elements, animals and ancestors. The third part of the thesis investigates processes underlying the creation of real people by focussing on Menkü life cycle, kinship and social organisation. A person's life is depicted in the way it is geared towards the acquisition of gendered skills of production and reproduction, which are fully manifested by the married couple. An outline of the Menkü system of classificatory marriage reveals the stress on the married couple from another point of view. It will be shown that the ideal marriage partners are identified by a conflation of gender and affinity. The last chapter explores the generation of sociality as it reveals itself in happiness, abundance and togetherness. It shows the extent to which a high communal morale is preconditioned upon non-hierarchical gender-relationships.

Social status influences reproductive physiology in many species, and sex change in marine teleost fishes provides an excellent model to understand how an organism can modulate its reproductive system in response to social stimuli. The series of experiments presented in this dissertation has focused on the proximate mechanisms underlying sex change and, in particular, the neuroendocrine factors that might translate social information into physiological changes. The bluebanded goby (Lythrypnus dalli) is a sexually plastic fish, and the dominant female typically changes sex when the male is removed from the social group. The direct physical interactions between the male and the females were found to be the main sensory cues that inhibit sex change. Sex steroids can both modulate and be modulated by behavior, and as a result they have been the most obvious candidates for a key role in the regulation of sex change. Males and females showed similar diurnal patterns for steroid hormones, but females had significantly higher water-borne estrogen levels. Concentrations of estradiol, testosterone and 11-ketotestosterone presented sex and tissue differences in brain, gonad and muscle, and they varied in complex ways in different tissues during sex change. The neurotransmitter serotonin (5-HT) has been suggested to be involved in the inhibition of socially regulated sex change because of its role in the modulation of both reproductive and aggressive behavior. None of the pharmacological manipulations performed in L. dalli to alter serotonergic activity was able to overcome the input from the social environment and affect sex change. Neither monoamine levels nor the area or number of 5-HT immunoreactive neurons were different between males, females and sex changers or between dominant and subordinate females. The results do not support the hypothesis of a serotonergic inhibition on sex change in L. dalli, but show that rapid changes in brain androgen levels might be implicated in inducing behavioral or morphological changes associated with sex reversal. Also, steroids respond to changes in the social environment in different ways in different tissues so local steroid synthesis should receive greater attention, and caution is required when using circulating levels to understand behavioral regulation.

The purpose was to analyze the role of dopamine D1 and D2 receptors in conditioned place preference (CPP) of a relatively high dose (5 mg/kg) of methylphenidate (MPH) in adolescent male and female rats, as well as the role of these receptors in the effects of MPH on brain-derived neurotrophic factor (BDNF). The primary mechanism of MPH in the brain is the blockade of the dopamine transporter, yielding an increase of dopamine in the synaptic cleft and is the basis for the rewarding properties of MPH. An initial preference given on postnatal day (P)32 yielded no preference for any context in a three-chambered shuttle box with removable dividers, thus, a biased procedure was used. Conditioning began the day after the initial preference test on P33. On conditioning trials, animals were first administered saline or their respective antagonist (D1 antagonist: 0.1 or 0.2 mg/kg SCH-23390; D2 antagonist: 0.01 or 0.03 mg/kg Eticlopride HCl), followed by methylphenidate (MPH; 5mg/kg). Approximately 10 min after MPH administration, rats were placed into the paired context for a 10 min trial. The choice of the paired context was balanced across animals. In a separate session, all animals received saline in the opposing context. One day post-conditioning on P38, a preference test was administered with dividers removed. Preference was determined through the amount of time spent in the paired context as compared to time spent in the unpaired context on the post-conditioning preference test. One day following the preference test on P39, brain tissue was removed, and nucleus accumbens and striatum analyzed for BDNF. Results showed that MPH produced an increased preference on the post-conditioning preference test that was blocked by either dose of SCH-23390, but was not affected by either dose of eticlopride. Additionally, the higher dose of SCH-23390 resulted in a conditioned place aversion in males, which may be due to the increased presence of dopamine D1 receptors in adolescent males. MPH produced a robust significant increase in BDNF in both nucleus accumbens and striatum, and this increase was alleviated by SCH-23390, but the effect on BDNF is still to be analyzed relative to D2 antagonism. These results show that MPH results in a conditioned place preference in adolescent male and female rats, and these effects appear to be mediated by the dopamine D1 receptor. Further, MPH results in a significant increase of BDNF in drug reward areas of the brain, which has implications towards synaptic plasticity in these regions in response to MPH.

The neuropeptides galanin and neuropeptide Y (NPY) play an important role in the reproduction of rodents, e.g. by modulating the release of gonadal hormones, the nutritional status by effects on feeding behavior and also by influencing mating behavior. There are age- and gender- differences in galanin- and NPY- like immunoreactivities (LIs) in brain areas important for higher functions including the hippocampal formation (HiFo) and cortex, that are related to the concentrations of 17β-estradiol. Neuropeptides in general are currently not considered critical in normal integrative neuronal functions but are rather thought to act as slow modulators during periods of stress or injury. In the present thesis we attempted to investigate, if the normal cyclical changes in the female sex-hormone 17β-estradiol can affect neurotransmission in brain areas important for memory, cognition and mood. We studied not only ”long term” (days and weeks) but also ”short-term” (one hour) effects on galanin and NPY concentrations in 17β-estradiol-primed ovariectomized (ovx) rats and mice. Radioimmunoassay (RIA) of galanin-LI in extracts of brain tissues from ”long-term” 17β-estradiol-treated ovx rats showed that its effects on galanin are dependent on boththe dose and on duration. Galanin - and NPY-LI in brain tissues of young ovx rats and mice increased in response to 17β-estradiol treatment in the HiFo, frontal cortex and striatum already within hours. This effect was not blocked by Tamoxifen® in rats. The mechanism of the 17β-estradiol effects on galanin levels in the rat HiFo may be related to decreased release of galanin into the extracellular fluid, since galanin-LI decreased in microdialysis samples two hours after a single injection of 17β-estradiol. Species differences were observed with regards to galanin, possibly due to tissue and species differences in the distribution of estrogen receptors. In the HiFo and caudate nucleus of mice, we found an increase in NPY-transcript after two hours by means of insitu hybridization, perhaps a compensatory up-regulation of NPY mRNA after increased 17β-estradiol-induced release in these areas. Taken together with no effects of Tamoxifen® on the levels on galanin in the HiFo of rats, the short duration, and the fact that the density of classical estrogen receptors seems to be limited in the striatum, we suggest that these effects are mediated through a membrane-related mechanism perhaps not involving the classical ER route. With an antiserum raised against the C-terminal end of the first 16 aminoacids of galanin- the sequence important for binding of intact galanin to its receptor - we found a novel compound which appears to be a homologue to galanin. Chromatographical analysis revealed that it was not galanin(1-29) or the galanin related peptide, galaninlike peptide (GALP), but appeared with immunohistochemistry in the galanin systems in the brain and was further influenced by 17β-estradiol in the HiFo and frontal cortex in a similar manner as galanin(1-29). In conclusion, tissue concentrations of galanin, a putative galanin homologue and NPY can be altered already after one hour by 17β-estradiol treatment e.i. in the HiFo. These ”short-term” effects are most likely to be due to effects on estrogen-primed peptide release which might influence mechanisms important for memory, cognition and mood.

Rose... assim era denominada a primeira revista gay editada no Brasil entre fins da década de 1970 e princípios de 1980. Em suas páginas eram publicadas informações do cenário artístico-cultural da época, contos eróticos, estórias em quadrinho, cartuns, anúncios de homens interessados em corresponder-se com outros homens, artigos que versavam sobre a homossexualidade masculina. Nessas páginas havia, também, uma profusão de corpos masculinos tendendo a nudez. Entretanto, nos limites dessa dissertação a revista Rose, não foi considerada apenas como veículo de comunicação e entretenimento, mas, antes disso, tomada como fonte histórica. Enquanto portadora de um conjunto de pedagogias do gênero e da sexualidade, a revista está implicada na produção de um modelo de masculinidade homossexual normalizada. A partir do referencial teórico dos Estudos de Gênero, desde uma perspectiva feminista e pós-estruturalista, analiso o enunciado que articula a masculinidade homossexual a comportamentos efeminados. E é a abjeção a tais comportamentos que servirá de base para a construção do homem gay discreto, marcadamente masculinizado. Portanto, a discrição – enquanto signo de masculinidade – parece assegurar a inteligibilidade social desses homens, “autorizando” sua própria existência. De qualquer maneira, a revista não deve ser reduzida a problemática aqui desenvolvida, uma vez que nela estão presentes outros enunciados.
Rose... so it was named the first gay magazine edited in Brazil between late 1970s and early 1980s. On its pages, information about the cultural-artistic scene of that time, erotic stories, stories in comics, cartoons, advertisements of men interested in corresponding with other men, and articles that dealt with male homosexuality were published. On those pages there was also a profusion of male bodies tending to nudity. However, within the bounds of this dissertation, Rose magazine has not been considered only as a vehicle of communication and entertainment, above all, it has been taken as a historical source. As a carrier of a set of pedagogies of gender and sexuality, the magazine is involved in producing a normalized model of homosexual masculinity. Based on the theoretical referential of Gender Studies from a feminist and post-structuralist perspective, it was analyzed the “enunciation” that articulates the homosexual masculinity to feminine behaviors. It is the degradation of such behaviors that will serve as the basis for the construction of a discrete gay man, with a distinct male-like behavior. Therefore, discretion – as a sign of masculinity – seems to ensure the social intelligence of those men, "authorizing" their own existence. However, the magazine should not be reduced to the problematic here developed, since there are other issues presented in it.

Puberty is a critical period of development characterized by rapid physiological changes and significant brain reorganizing and remodeling. These rapid changes render the developing brain particularly vulnerable to stress and immune challenge. In mice, exposure to an immune challenge (lipopolysaccharide; LPS) during puberty causes enduring effects on stress reactivity, cognitive functioning, and depression- and anxiety-like behaviors later in life. However, the mechanisms underlying these effects are unknown. The gut microbiome can profoundly influence the immune system. There is also close bidirectional communication between the gut microbiome and the central nervous system (CNS) through neural, endocrine and immune signaling pathways, which can alter brain chemistry and emotional behaviour. Thus, we hypothesized that altering microbial composition during puberty could mitigate acute immune responses and prevent enduring outcomes later in life. The current thesis examined the effect of gut manipulation with probiotics during puberty on LPS-induced immune responses and enduring anxiety- and depression-like behaviours, and stress-reactivity in adulthood, in male and female CD1 mice (Article 1). Next, we examined age and sex differences in gut microbial composition before and after exposure to an immune challenge. We also examined the effects of consuming a single strain probiotic bacterium (Lactobacillus Reuteri) during puberty on the immune response and the long-term changes in memory, anxiety-like behavior, and stress reactivity in adulthood (Article 2). Lastly, we examined how microbial colonization between pubertal and adult mice can alter acute peripheral and central inflammatory responses to LPS (Article 3). The current dissertation has addressed sex-specific vulnerabilities to an immune challenge during pubertal development and the moderating influence of the gut microbiome. These studies have demonstrated that manipulating the gut microbiome during puberty can mitigate acute immune responses and prevent enduring neurobehavioural outcomes later in life.

A análise da intelectualidade e de seu papel como um dos agentes de mudanças sociais e culturais é um tema que vem galgando espaços significativos na produção historiográfica. Neste trabalho, proponho um estudo sobre o percurso do pensamento feminista no Brasil Contemporâneo. Para tanto, escolhi três autoras que desempenharam um importante papel ao introduzir um olhar feminista no campo intelectual brasileiro: a jornalista Carmen da Silva, a escritora e editora Rose Marie Muraro e a socióloga Heleieth Saffioti. Através da palavra, estas mulheres colaboraram para o questionamento do conhecimento tradicional e misógeno. Trouxeram à luz novas interpretações para os problemas sociais, afirmando a análise das relações entre os sexos como um ponto fundamental para a compreensão e transformação da sociedade. Atentas às alterações na vida das mulheres que transcorriam ao longo do século XX, mantiveram os olhos focados na realidade brasileira. Na década de 1960, em meio a um regime ditatorial, seus escritos simbolizaram a liberdade almejada por mulheres e homens que sonhavam com a possibilidade de um país diferente. No período em questão, Carmen, Rose e Heleieth germinaram um debate, a partir de seus espaços de atuação, sobre a condição da mulher. Respectivamente, a Imprensa, a Igreja Católica e a Universidade. São instituições de onde surgiram parte significativa dos pensadores e da atividade intelectual no Brasil. Analisar as obras e as trajetórias de vida destas mulheres proporciona outros olhares sobre as relações de poder vigentes no contexto dos anos de 1960 e sobre o papel da intelectualidade na elaboração e difusão do pensamento feminista.
The analysis of the intellectuality and its role as one of the responsible for the social and cultural changes is a theme which is achieving meaningful positions in the historical production. In this study, I propose an analysis concerning to the development of the feminist thought in the Contemporary Brazil. So, three authors who have performed an important role in this field were chosen since they introduced a feminist perspective in the Brazilian intellectual environment. Such women are: the journalist Carmem da Silva, the writer and publisher Rose Marie Muraro and the sociologist Heleieth Saffioti. These women have collaborated to the inquiring of the traditional and misogynist knowledge through their concepts. They have brought to light new interpretations to the social problems, claiming the analysis of the gender relations as a fundamental subject for the comprehension and changing of the society. Being careful about the changes in the women lives that happened during the XX century, they kept their eyes focused on the Brazilian reality. In the 1960s, during the dictatorial period, their writings symbolized the desired freedom by women and men who dreamed about the possibility of a different country. In that period, Carmen, Rose e Heleieth evolved a debate about the women's condition starting from their working fields. Respectively, the press, the Catholic Church and the Universities are institutions from where emerged a significant part of the scholars and of the intellectual activity in Brazil. The analysis of these women's issues and their course of life provides us with a different point of view about the relation of the power in effect in the context of the 1960s and on the role of the intellectuality in the development and spreading of the feminist thought.

The Australian zebra finch (Taeniopygia guttata) serves as an excellent model organism for studying the mechanisms that influence brain sexual differentiation. The brain and behavior of the zebra finch are sexually dimorphic. The regions of the brain that control the learning and production of song (song control nuclei) are significantly larger in the male brain than in the female brain and only males sing courtship songs, thus the majority of past research has focused on the development of these sex differences. In the majority of mammals, brain sexual differentiation occurs because hormones secreted from the gonads act to initiate male or female brain development. In zebra finches, estradiol is sufficient to masculinize the male brain, however manipulations of developmental hormone exposure fail to fully reverse the sex differences in song nuclei size. Furthermore, genetic females induced to develop functional testicular tissue do not develop a completely masculinized song system and castration has no effect on development of the song system in males. The source of the increased estrogenic signal in male zebra finch brain has yet to be identified, but data suggest that other neuronal factors play a role in development of the song control nuclei. Coregulators, such as coactivators and corepressors, are proteins and RNA activators that work by enhancing or depressing transcriptional activity of the nuclear steroid receptor with which they associate. Coregulators also modulate the development of sex-specific brain morphology and behavior in rodents and birds and may help to explain the difficulties observed in altering song nuclei development via castration and gonadal hormone replacement. As an estrogen receptor-α coactivator, ribosomal protein L7 (RPL7) is able to make the brain more sensitive to estradiol by enhancing the effects of steroid receptor action. Therefore, this dissertation addressed the following questions regarding RPL7: (1) is RPL7 expression sexually dimorphic in the song nuclei of the zebra finch brain?; (2) is RPL7 protein expression regulated by steroid hormones?; and (3) does decreasing RPL7 protein expression with antisense oligonucleotides alter neuronal survival in vivo and song nuclei size and neuron number in vitro? Collectively, these studies will provide valuable information about the role of steroid receptor coactivators in development of the zebra finch song system and on the role of coactivators on sexual differentiation of the brain.

Myelin is an extensive cell membrane produced by oligodendrocytes to ensheath neuronal axons in the central nervous system with the primary goal of maximizing the efficiency of electrochemical impulse transmission. During brain development, oligodendrocytes differentiate into myelin forming cells in a tightly regulated process which makes them vulnerable to multiple insults. Previous results from the laboratory showed that the timing of oligodendrocyte differentiation and rat brain myelination were altered by perinatal exposure to buprenorphine and methadone, opioid analogues used for treating pregnant addicts. The mechanism by which these opioids exerted their effects involved two opioid receptors, the μ-opioid receptor (MOR) and the nociceptin/orphanin FQ receptor (NOR). However, the role of these receptors and their endogenous ligands in controlling the timing of myelination under normal physiological conditions of brain development is not known. In this dissertation, we found that the endogenous MOR ligand endomorphin-1 (EM-1) acts as a strong promoter of rat pre-oligodendrocyte differentiation, but surprisingly, this effect is observed only in cells isolated from female pups. Interestingly, the stimulatory action of EM-1 was abolished upon co-incubation with the endogenous NOR ligand, nociceptin. Moreover, injections of NOR antagonist to 9-day-old female and male rat pups accelerated rat brain myelination in female rat pups with no significant changes in their male counterparts. Interestingly, the lack of major sex-dependent differences in developmental brain levels of EM-1 and nociceptin and the presence of the two receptors MOR and NOR in male and female oligodendrocytes suggested that the observed sex-specific responses may be highly dependent on critical intrinsic sex-dependent differences within these cells. Although nociceptin alone did not exert observable effects on pre-oligodendrocyte maturation, it increased the number of cells expressing Ki-67, a cell proliferation indicator, in oligodendrocyte progenitor cultures. These results suggest that nociceptin may be playing a stage specific role in oligodendrocyte development during brain maturation. The finding of critical functions of EM-1 and nociceptin in the developing female oligodendrocytes and brain myelination highlights the need for considering sexual dimorphism in the design of safer and more effective therapeutic approaches for treating opioid abuse, pain, and demyelinating disease as multiple sclerosis.

Simple content analysis methods, such as the Bechdel test and measuring percentage of female talk time or characters, have seen a surge of attention from mainstream media and in social media the last couple of years. Underlying assumptions are generally shared with the gender role socialization model and consequently, an importance is stated, due to a high degree to which impressions from media shape in particular young children’s identification processes. For young girls, the Disney Princesses franchise (with Frozen included) stands out as the number one player commercially as well as in customer awareness. The vertical lineup of Disney princesses spans from the passive and domestic working Snow White in 1937 to independent and super-power wielding princess Elsa in 2013, which makes the line of films an optimal test subject in evaluating above-mentioned simple content analysis methods. As a control, a meta-study has been conducted on previous academic studies on the same range of films. The sampled research, within fields spanning from qualitative content analysis and semiotics to coded content analysis, all come to the same conclusions regarding the general changes over time in representations of female characters. The objective of this thesis is to answer whether or not there is a correlation between these changes and those indicated by the simple content analysis methods, i.e. whether or not the simple popular methods are in general coherence with the more intricate academic methods.

Betyg VG (skala IG-VG)

But : La perte de l’intégrité de la barrière hémo-encéphalique (BHE) est l’une des caractéristiques principales de la sclérose en plaques. Cette augmentation de la perméabilité est associée à une désorganisation des molécules de jonction serrée et à une augmentation de l’expression de molécules d’adhérence essentielles à l’extravasation des cellules immunitaires. Identifier de nouvelles molécules impliquées dans ce processus est donc crucial pour le développement de nouvelles thérapies contre la sclérose en plaques visant à promouvoir l’intégrité de la BHE et à diminuer la migration des leucocytes dans le système nerveux central (SNC) au cours du processus neuro-inflammatoire. Dans cette étude, le rôle spécifique de la molécule d’adhérence ALCAM, qui est exprimé à la surface des cellules endothéliales de la BHE (CE-BHE) et de certains sous-types de leucocytes, a été évalué. Méthodologie : À l’aide d’une analyse protéomique exhaustive, notre laboratoire a identifié ALCAM comme étant une molécule d’adhérence surexprimée par les CE-BHE mises en culture dans un milieu pro-inflammatoire. Dans le but d’étudier le rôle spécifique d’ALCAM durant la diapédèse leucocytaire, nous avons induit chez des souris de type sauvages et des souris ALCAM déficientes l’encéphalite auto-immune expérimentale (EAE), le modèle animal de la sclérose en plaques. Le rôle d’ALCAM a aussi été étudié à l’aide d’un système d’adhérence sous flux laminaire. Cet appareil, qui imite un capillaire cérébral, permet de suivre en temps réel le mouvement des leucocytes, soumis à une pression physiologique, dans un tube couvert à sa base par des CE-BHE. Résultats : En utilisant ce système d’adhérence, j’ai pu démontrer que des anticorps dirigés contre ALCAM réduisent de façon significative le roulement et l’adhérence de monocytes CD14+ humains à la surface de CE-BHE. Par ailleurs, ces anticorps préviennent de façon marquée la diminution de la vitesse moyenne des cellules au cours de l’expérience. Par le fait même, j’ai aussi observé une réduction significative de l’extravasation des monocytes traités avec de l’anti-ALCAM au travers de CE-BHE dans un modèle statique de migration. Subséquemment, j’ai démontré que ces monocytes migrent plus rapidement et en plus grand nombre au travers d’une barrière constituée de cellules endothéliales méningées à comparer à des CE-BHE. Bien que des observations similaires ont été effectuées en utilisant des lymphocytes T CD4+ humains ex vivo, j’ai été incapable de reproduire ces résultats à l’aide de cellules Th1 et Th17 réactivées in vitro. Par opposition à nos données in vitro, j’ai découvert que les souris déficientes en ALCAM développent une EAE active plus sévère que celle observée chez des souris de type sauvages. Cette EAE est par ailleurs associée à une infiltration périvasculaire de lymphocytes T pro-inflammatoires et de monocytes/macrophages de type M1 plus marqué chez les souris ALCAM déficientes. L’induction d’une EAE par transfert adoptif, dans laquelle des cellules immunitaires de type sauvage réactivées par du MOG sont injectées à des souris déficientes en ALCAM, suggère que la pathophysiologie observée durant l’EAE active serait liée à l’absence d’ALCAM au niveau de la BHE. Une caractérisation de la barrière des souris ALCAM déficientes non immunisées a par la suite révélé une réduction de l’expression de certaines molécules de jonction serrée. Une analyse plus poussée a par ailleurs démontré qu’ALCAM est lié indirectement à des molécules de jonction serrée des CE-BHE, ce qui expliquerait l’augmentation de la perméabilité de celle-ci chez les souris déficientes en ALCAM. Une analyse de la perméabilité intercellulaire de la BHE effectuée in vitro a d’autre part corrélé ces résultats. Conclusion : Collectivement, nos données prouvent qu’ALCAM joue un rôle prépondérant dans la diapédèse des monocytes, mais pas des lymphocytes Th1 et Th17 au travers de la BHE. Par ailleurs, nos résultats suggèrent qu’ALCAM remplit une fonction biologique cruciale favorisant le maintien de l’intégrité de la BHE en agissant comme molécule adaptatrice intermédiaire entre les molécules de jonction serrées et le cytosquelette. De cette façon, l’absence d’ALCAM au niveau des CE-BHE promeut indirectement le recrutement de leucocytes pro-inflammatoires dans le SNC des souris atteintes de l’EAE en augmentant la perméabilité des vaisseaux sanguins de la BHE.
Aim: The loss of blood-brain barrier (BBB) integrity is a hallmark of multiple sclerosis. It is associated with a disorganization of junctional molecules and an upregulation of cell adhesion molecules essential for immune cell transmigration. Identifying novel key players involved in this process is thus crucial for the development of MS therapies aimed at promoting BBB integrity and decreasing leukocytes trafficking into the central nervous system (CNS) during neuroinflammation. In this study, the specific role of the adhesion molecule ALCAM, found on BBB endothelial cells (BBB-ECs) and subsets of leukocytes, was assessed. Methods: We first identified ALCAM as an important molecule upregulated during inflammation in a proteomic screen of in vitro cultured primary human BBB-ECs. In order to study the effects of ALCAM on leukocyte transmigration, both active and passive experimental autoimmune encephalomyelitis (EAE) was induced in ALCAM KO and WT animals. The specific role of ALCAM during leukocyte transmigration was also assessed using a modified adhesion assay under sheer-stress, in which leukocytes flow across a capillary-like channel lined with a monolayer of BBB-ECs under physiological pressure. Results: Using the modified adhesion assay, we demonstrated that anti-ALCAM blocking antibodies significantly reduce the rolling and the adhesion of human CD14+ monocytes interacting with primary human BBB-ECs, as well as prevent their overall decrease in velocity. Concurrently, we also observed a significant reduction in the migration of ex vivo CD14+ monocytes, across a monolayer of human BBB-ECs. These monocytes also migrated more rapidly and in higher number across meningeal endothelial cells, as compared to BBB-ECs. While similar observations were made using ex vivo CD4+ T lymphocytes, we failed to reproduce these results using in vitro activated Th1 and Th17 cells. In opposition to our in vitro data, ALCAM KO mice developed a more severe active EAE associated with a significant increase in perivascular infiltration of pro-inflammatory lymphocytes (Th1/Th17) and M1 monocytes/macrophages, as compared to WT controls. In addition, EAE transfer experiments, in which ALCAM KO mice received WT MOG-reactivated splenocytes, suggested that the pathophysiology observed in active EAE was linked to the absence of ALCAM on BBB-ECs. Phenotypic characterization of un-immunized ALCAM KO mice revealed a reduced expression of BBB junctional proteins. Further analysis showed that ALCAM is indirectly associated with tight junction molecules of the BBB-ECs, which explains the increased CNS parenchymal blood vessel in vivo permeability in ALCAM KO animals. Correlating with these data, primary culture of mouse brain BBB-ECs was shown to possess a lower TEER and an increased permeability coefficient. Conclusion: Collectively, our data provide evidence of the implication of ALCAM in monocyte transmigration, but not Th1 or Th17 lymphocyte diapedesis across CNS endothelium. Our results also point to a biologically crucial function of ALCAM in maintaining BBB integrity by acting as an adaptor molecule between tight junctions and the cytoskeleton. As such, the absence of ALCAM at the level of BBB-ECs indirectly promotes the recruitment of pro-inflammatory leukocytes in the CNS of EAE animals by increasing the BBB vessels permeability.

Tese de doutoramento em Altos Estudos Contemporâneos, na especialidade de Ciência Política (História Política e Estudos Internacionais), apresentada à Faculdade de Economia da Universidade de Coimbra
A presente investigação analisa e compara material publicado por dois jornais, – Folha de São Paulo, do Brasil, e Público, de Portugal -, sobre referendos realizados nos dois países, respectivamente, em 2005 e 2007. O objetivo é verificar se nesse material há falas com argumentos que possam ser considerados úteis para contribuir com um processo deliberativo, na perspectiva da democracia defendida por Jürgen Habermas. Ancorado numa sugestão de Simone Chambers, o material jornalístico é classificado como retórica plebiscitária ou retórica deliberativa. A retórica plebiscitária se caracteriza pela presença de mais elementos que não contribuem para a realização de uma deliberação pública, enquanto a deliberativa contém significativa presença de subsídios considerados importantes para o desenvolvimento desse processo. O reforço de alguns elementos no material jornalístico, – e a investigação avalia e quantifica quais elementos a mídia privilegia -, pode fazer com que se aproxime ou se distancie daquilo que é qualificado como importante para um debate público numa perspectiva habermasiana. A decisão de acionar mais um ou outro elemento está entre as opções que a mídia faz. Ao optar, ela sai de uma zona de fronteira, com várias possibilidades em aberto, e realiza um processo de demarcação. E, ao demarcar, ela estabelece limites, seja para um ou para outro processo. Considerando que a mídia tem potenciais ambivalentes, a investigação assume este pressuposto: não é possível definir a priori o papel que a mídia desempenha em eventos específicos de deliberação pública, como no caso dos referendos, isto porque em seu material comparecem todos os elementos da retórica, tanto os tendentes a favorecer como aqueles que prejudicam um processo deliberativo. Mas dada sua lógica de produção e divulgação, ela revela alguns dos seus limites que a impedem de complexificar os temas da agenda pública. E a hipótese que se assume nesta tese é que as escolhas da mídia privilegiam mais os elementos da retórica que se coadunam com a lógica da evidência, que é refratária a um processo argumentativo. Por acionar em maior número os elementos que são limitadores de um processo argumentativo, é temerário apontar a mídia como fórum central para a deliberação pública. E, se o seu poder de abrangência pode ser tomado como potencialmente útil para a realização de processos deliberativos nas democracias contemporâneas, a simples disponibilidade desse dispositivo não permite chegar à conclusão açodada de que sua prática contribua efetivamente para o desenvolvimento do debate público. Pelo seu potencial, e por permitir que em seu interior também circule material identificado como uma retórica deliberativa, até pode-se ver na mídia um ator capacitado a realizar um papel complementar, mas não central, no processo mais amplo da deliberação pública. E, nessa linha de análise, não se pode descartar por completo a possibilidade de o material produzido pela mídia ser desencadeador de um processo deliberativo na sociedade ao ser apropriado ou reinterpretado de diferentes maneiras pelos diversos atores da esfera pública.