Thesis (D.P.H.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed Sept. 22, 2008). Includes bibliographical references.

Trata-se de uma pesquisa com o objetivo de compreender o adoecimento pelo tétano neonatal, a partir da análise da trajetória de um grupo de 19 mães de crianças que morreram em conseqüência da doença no período compreendido entre 1997 e 2002, em municípios do Estado de Minas Gerais, Brasil. Para a análise, foram utilizadas Políticas de Assistência à Saúde da Mulher, Imunização e a Estratégia de Saúde da Família. Os dados foram obtidos em entrevistas semi-estruturadas e nos registros secundários do Cartão de Vacina e do Cartão da Gestante. A metodologia adotada foi de natureza quantitativa e qualitativa, com enfoque nas representações sociais sobre a experiência da doença e o risco de adoecimento. Para a análise das entrevistas, utilizou-se o instrumento do discurso do sujeito coletivo. As mulheres, em sua maioria, são multíparas em idade fértil, desconhecem a doença e seus mecanismos de prevenção, embora relatem as principais manifestações clínicas do tétano neonatal associando-o ao mal-de-sete-dias. São evidentes as práticas de tratamento inadequado do coto umbilical utilizadas pelas mulheres, sedimentadas no risco potencial para a doença, a irregularidade do pré-natal, a ausência ou a administração de doses insuficientes de vacina para a proteção do tétano neonatal e do tétano acidental, e procedimentos pós-parto domiciliar impróprios utilizados pelas parteiras ou curiosas. Observou-se, pelas falas das mães, a presença da crendice sobre os cuidados com o coto umbilical e a falha dos serviços no processo de educação para a saúde. Urge implementar esforços estratégicos específicos, direcionados à vigilância epidemiológica, à capacitação de parteiras e aos profissionais de saúde, incrementar serviços de pré-natal e ampliar a cobertura vacinal para as mulheres, principalmente nas regiões de onde provêm os casos da pesquisa, contribuindo, assim, para a eliminação da doença. / This research aimed to understand the illness caused by neonatal tetanus, based on the analysis of a group of 19 mothers’ histories involving children who died of the disease in communities located in the State of Minas Gerais, Brazil, between 1997 and 2002. The analysis was based on Women’s Health Care and Immunization Policies and the Family Health Strategy. Data were collected through semistructured interviews and secondary records from the Vaccination Card and the Pregnant Woman’s Card. A quantitative and qualitative methodology was adopted, focusing on the social representations about the disease experience and the risk of getting ill. The interviews were analyzed on the basis of collective subject discourse. Most women were of fertile age and multiparous and did not know about the disease and its prevention mechanisms, although they reported on the main clinical signs of neonatal tetanus, associating it with the “seven-day disease". This study revealed the women’s use of inadequate practices for treating the umbilical cord stump, based on the potential risk of catching the disease, irregular antenatal treatment, the absence or administration of insufficient doses of the vaccine to protect against neonatal and accidental tetanus, and inappropriate post-home delivery procedures used by midwifes. The mothers’ discourse revealed the presence of popular beliefs on care related to the umbilical cord stump and the services’ deficiency in the health education process. There is an urgent need to implement specific strategic efforts, aimed at epidemiological supervision, the training of midwifes and health professionals, and to increase prenatal services and expand vaccination coverage for women, mainly in the research cases’ regions of origin, thus contributing to the elimination of this disease.

A toxina tetânica é uma proteína sintetizada pelo bacilo Clostridium tetani que após destoxificação através da ação do formol, continua apresentando propriedades antigênicas e imunogênicas, obtendo a denominação toxóide tetânico. A síntese dessa proteína ocorre quando esse bacilo encontra-se na sua forma vegetativa e em meio de cultura específico relativamente complexo contendo glicose e peptonas. O efeito simultâneo de diferentes níveis de glicose (Go) e N-Z Case TT® (NZo) como fontes de carbono e nitrogênio, respectivamente, na produção de toxina tetânica foi investigada nesta primeira parte do trabalho em cultivo estático por meio de planejamento fatorial em estrela com cinco níveis e avaliado por metodologia de superfície de resposta, com a finalidade de otimização do processo. O valor mais alto de toxina tetânica encontrado, correspondente a Go = 9,7 g/L e NZo = 43,5 g/L, foi 79% maior que aqueles obtidos em condições padrões de cultivo (Go = 8,0 g/L e NZo = 25,0 g/L). Também foram realizados cultivos de C. tetani utilizando o processo descontínuo alimentado com diferentes protocolos para a correção da concentração de glicose no meio de cultivo ao longo do tempo em diferentes concentrações iniciais de N-Z Case TT®. Dois grupos de ensaios foram executados: a) experimentos realizados com a correção da concentração de glicose para 3,0 g/L nos instantes 16, 56 e 88 h e b) experimentos com correção inicial da concentração de glicose para 3,0 g/L e após esta cair para 1-1,5 g/L. O primeiro protocolo de correção da concentração de glicose e NZo = 50,0 g/L foram as melhores condições para obtenção de toxina tetânica. Nestas condições, o título de toxina tetânica foi 300% maior que aqueles obtidos em cultivos padrão. / The tetanus toxin is a neurotoxin synthesized by the bacillus Clostridium tetani that, after detoxification with formaldehyde, still exhibits antigenic and immunologic properties, hence its denomination of tetanus toxoid. Such a neurotoxin is produced by cultivations of the microorganism in vegetative form on a relatively complex specific medium containing glucose and peptone. The simultaneous effects of the starting levels of glucose (Go) and N-Z Case TT® (NZo) as carbon and nitrogen sources, respectively, on the production of tetanus toxin, have been investigated in this work in static cultivations by means of a five-levels star-shaped experimental design and evaluated by Response Surface Methodology (RSM) for optimization purposes. The highest final average yield of tetanus toxin, achieved at Go = 9.7 g/L and NZo = 43.5 g/L, was 79% higher than that obtained with standard cultivations (Go = 8.0 g/L and NZo = 25.0 g/L). Also, there were carried out cultivations of C. tetani using fed-batch process at different protocols to correct the glucose concentration in the cultivation medium along the time at different initial N-Z Case TT® concentrations (NZo). Two series of runs were performed: a) experiments with the correction of the glucose concentration to 3.0 g/L in the times 16, 56 and 88 hours and b) experiments with initial correction of the glucose concentration to 3.0 g/L and after it to drop to 1-1,5 g/L. The former protocol to correct the glucose concentration and NZo = 50.0 g/L were the best condition to obtain tetanus toxin. In these conditions, the yield of tetanus toxin was 300% higher than that obtained with standard cultivations.

A toxina tetânica é uma proteína sintetizada pelo bacilo Clostridium tetani que após destoxificação através da ação do formol, continua apresentando propriedades antigênicas e imunogênicas, obtendo a denominação toxóide tetânico. A síntese dessa proteína ocorre quando esse bacilo encontra-se na sua forma vegetativa e em meio de cultura específico relativamente complexo contendo glicose e peptonas. O efeito simultâneo de diferentes níveis de glicose (Go) e N-Z Case TT® (NZo) como fontes de carbono e nitrogênio, respectivamente, na produção de toxina tetânica foi investigada nesta primeira parte do trabalho em cultivo estático por meio de planejamento fatorial em estrela com cinco níveis e avaliado por metodologia de superfície de resposta, com a finalidade de otimização do processo. O valor mais alto de toxina tetânica encontrado, correspondente a Go = 9,7 g/L e NZo = 43,5 g/L, foi 79% maior que aqueles obtidos em condições padrões de cultivo (Go = 8,0 g/L e NZo = 25,0 g/L). Também foram realizados cultivos de C. tetani utilizando o processo descontínuo alimentado com diferentes protocolos para a correção da concentração de glicose no meio de cultivo ao longo do tempo em diferentes concentrações iniciais de N-Z Case TT®. Dois grupos de ensaios foram executados: a) experimentos realizados com a correção da concentração de glicose para 3,0 g/L nos instantes 16, 56 e 88 h e b) experimentos com correção inicial da concentração de glicose para 3,0 g/L e após esta cair para 1-1,5 g/L. O primeiro protocolo de correção da concentração de glicose e NZo = 50,0 g/L foram as melhores condições para obtenção de toxina tetânica. Nestas condições, o título de toxina tetânica foi 300% maior que aqueles obtidos em cultivos padrão. / The tetanus toxin is a neurotoxin synthesized by the bacillus Clostridium tetani that, after detoxification with formaldehyde, still exhibits antigenic and immunologic properties, hence its denomination of tetanus toxoid. Such a neurotoxin is produced by cultivations of the microorganism in vegetative form on a relatively complex specific medium containing glucose and peptone. The simultaneous effects of the starting levels of glucose (Go) and N-Z Case TT® (NZo) as carbon and nitrogen sources, respectively, on the production of tetanus toxin, have been investigated in this work in static cultivations by means of a five-levels star-shaped experimental design and evaluated by Response Surface Methodology (RSM) for optimization purposes. The highest final average yield of tetanus toxin, achieved at Go = 9.7 g/L and NZo = 43.5 g/L, was 79% higher than that obtained with standard cultivations (Go = 8.0 g/L and NZo = 25.0 g/L). Also, there were carried out cultivations of C. tetani using fed-batch process at different protocols to correct the glucose concentration in the cultivation medium along the time at different initial N-Z Case TT® concentrations (NZo). Two series of runs were performed: a) experiments with the correction of the glucose concentration to 3.0 g/L in the times 16, 56 and 88 hours and b) experiments with initial correction of the glucose concentration to 3.0 g/L and after it to drop to 1-1,5 g/L. The former protocol to correct the glucose concentration and NZo = 50.0 g/L were the best condition to obtain tetanus toxin. In these conditions, the yield of tetanus toxin was 300% higher than that obtained with standard cultivations.

Alterações na musculatura facial e/ou cervical são alguns dos primeiros sintomas encontrados nos pacientes com quadro clínico de tétano. No entanto, a atuação fonoaudiológica como área de conhecimento que contribua para o restabelecimento do paciente com esse quadro clínico não é citada na literatura pesquisada. O objetivo desta dissertação foi caracterizar a atividade muscular e as funções orofaciais em pacientes com diagnóstico clínico de tétano internados em Unidades de Terapia Intensiva. Participaram deste estudo 13 pacientes internados na Unidade de Terapia Intensiva do Departamento de Moléstias Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo com diagnóstico clínico de tétano, no período de dezembro de 2005 a maio de 2007. A idade dos pacientes variou de 36 a 85 anos, com média de 53,69 anos, sendo 1 do gênero feminino e 12 do masculino. Os pacientes foram encaminhados para avaliação fonoaudiológica quando se encontravam em fase de convalescença e para esta foram utilizados dados contidos nos prontuários dos pacientes e um protocolo específico de avaliação da disfagia. Este protocolo se divide em duas seções - Exame das funções oromotoras e testes clínicos da deglutição. Esta dissertação foi dividida em dois estudos. O primeiro estudo teve como objetivo a caracterização da atividade muscular e das funções orofaciais e a identificação de fatores clínicos e/ou testes de deglutição que poderiam estar mais relacionados a esta patologia. De acordo com os resultados a maioria dos aspectos avaliados foi considerada prioritariamente alterada. O fator clínico Reflexo de GAG e a etapa de elevação laríngea do teste clínico de deglutição de água encontraram-se alterados em todos os participantes que puderam ser avaliados. Os fatores clínicos movimento da língua e presença de tosse e/ou mudança vocal foram os aspectos que se relacionaram quando se comparou as duas etapas da avaliação. O segundo estudo teve como objetivo a caracterização do quadro clínico, da atividade muscular e das funções orofaciais e a determinação de aspectos e/ou alterações que poderiam ser consideradas mais comuns a este grupo de pacientes. O foco tetânico que mais prevaleceu foi o decorrente de fatores externos e traumáticos, o período de incubação da doença teve como média 7 dias e o de progressão 1 dia. Todos os participantes foram intubados, traqueostomizados, fizeram uso de sedação, de vias alternativas de alimentação e de ventilação mecânica. Os fatores clínicos mobilidade de língua, qualidade vocal e funções motoras da fala apresentaram predomínio de um tipo de alteração. Os resultados do estudo permitiram a comprovação das alterações miofuncionais orofaciais já elencadas na literatura sobre o paciente com quadro clínico de tétano, assim como o levantamento de novas caracterizações musculares e funcionais pertinentes ao Sistema xii Estomatognático realizado por profissionais com expertise na área. O estudo permitiu uma melhor e maior possibilidade de direcionamento da avaliação e tratamento deste grupo de pacientes, promovendo a divulgação de um material inicial que associe os sintomas e sinais clínicos por meio de processo de avaliação clínica padronizada. / Alterations of the facial and/or cervical muscles are a few of the symptoms found in patients with tetanus. Speech-language intervention, however, as a field of knowledge that can contribute for the reestablishment of this type of patient, is not mentioned in the consulted literature. The purpose of this dissertation was to characterize the muscle activity and the orofacial functions in patients, hospitalized at an Intensive Care Unit, with the clinical diagnosis of tetanus. Participants of this study were 13 patients hospitalized in the Intensive Care Unit of the Department of Infectious and Parasitic Diseases of the Clinical Hospital of the School of Medicine of the University of São Paulo with the diagnosis of tetanus, in the period of December 2005 and May 2007. The ages of the patients varied between 36 and 85 years, mean age of 53.69 years, being one female and twelve males. Patients were referred to a speech-language assessment during the phase of recovery. For this assessment, information contained in the medical charts, as well as a specific protocol for the assessment of dysphagia were used. This protocol is divided in two sections - examination of the oral-motor functions and clinical swallowing tests. This dissertation was divided in two studies. The first study had as a purpose to characterize the muscle activity and the orofacial functions, and to identify the clinical factors and/or swallowing tests that could be more related to this pathology. According to the results, most of the evaluated aspects were considered primarily altered. The clinical factor GAG Reflex and the elevation of the larynx during the clinical test of water were considered altered in all of the participants who could be assessed. The clinical factors of tongue movement and/or vocal changes were the aspects that presented correlation when comparing both stages of assessment. The second study had as a purpose to characterize, in clinical terms, the muscle activity and the orofacial functions and to determine aspects and/or alterations that could be considered common to this group of patients. The focus of tetanus which prevailed was that resulting from external and traumatic factors, the incubation period had as an average 7 days and the average of progression was of 1 day. All patients were intubated, used tracheostomy, used forms of sedation, used alternative forms of feeding and used mechanical ventilation. The clinical factors of tongue mobility, vocal quality and speech motor functions presented some type of alteration. The results of the study gave evidence to the orofacial myofuntional alterations already pointed in the literature as being related to patients with tetanus, as well as pointing new muscle and functional characterizations, pertinent to the Stomatognathic System, done by professionals with expertise in the field. The study allowed a better and greater possibility of direction in the assessment and treatment of this xiv group of patients, presenting a material that is associated to the symptoms and clinical signs through the process of standardized clinical evaluation.

Alterações na musculatura facial e/ou cervical são alguns dos primeiros sintomas encontrados nos pacientes com quadro clínico de tétano. No entanto, a atuação fonoaudiológica como área de conhecimento que contribua para o restabelecimento do paciente com esse quadro clínico não é citada na literatura pesquisada. O objetivo desta dissertação foi caracterizar a atividade muscular e as funções orofaciais em pacientes com diagnóstico clínico de tétano internados em Unidades de Terapia Intensiva. Participaram deste estudo 13 pacientes internados na Unidade de Terapia Intensiva do Departamento de Moléstias Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo com diagnóstico clínico de tétano, no período de dezembro de 2005 a maio de 2007. A idade dos pacientes variou de 36 a 85 anos, com média de 53,69 anos, sendo 1 do gênero feminino e 12 do masculino. Os pacientes foram encaminhados para avaliação fonoaudiológica quando se encontravam em fase de convalescença e para esta foram utilizados dados contidos nos prontuários dos pacientes e um protocolo específico de avaliação da disfagia. Este protocolo se divide em duas seções - Exame das funções oromotoras e testes clínicos da deglutição. Esta dissertação foi dividida em dois estudos. O primeiro estudo teve como objetivo a caracterização da atividade muscular e das funções orofaciais e a identificação de fatores clínicos e/ou testes de deglutição que poderiam estar mais relacionados a esta patologia. De acordo com os resultados a maioria dos aspectos avaliados foi considerada prioritariamente alterada. O fator clínico Reflexo de GAG e a etapa de elevação laríngea do teste clínico de deglutição de água encontraram-se alterados em todos os participantes que puderam ser avaliados. Os fatores clínicos movimento da língua e presença de tosse e/ou mudança vocal foram os aspectos que se relacionaram quando se comparou as duas etapas da avaliação. O segundo estudo teve como objetivo a caracterização do quadro clínico, da atividade muscular e das funções orofaciais e a determinação de aspectos e/ou alterações que poderiam ser consideradas mais comuns a este grupo de pacientes. O foco tetânico que mais prevaleceu foi o decorrente de fatores externos e traumáticos, o período de incubação da doença teve como média 7 dias e o de progressão 1 dia. Todos os participantes foram intubados, traqueostomizados, fizeram uso de sedação, de vias alternativas de alimentação e de ventilação mecânica. Os fatores clínicos mobilidade de língua, qualidade vocal e funções motoras da fala apresentaram predomínio de um tipo de alteração. Os resultados do estudo permitiram a comprovação das alterações miofuncionais orofaciais já elencadas na literatura sobre o paciente com quadro clínico de tétano, assim como o levantamento de novas caracterizações musculares e funcionais pertinentes ao Sistema xii Estomatognático realizado por profissionais com expertise na área. O estudo permitiu uma melhor e maior possibilidade de direcionamento da avaliação e tratamento deste grupo de pacientes, promovendo a divulgação de um material inicial que associe os sintomas e sinais clínicos por meio de processo de avaliação clínica padronizada. / Alterations of the facial and/or cervical muscles are a few of the symptoms found in patients with tetanus. Speech-language intervention, however, as a field of knowledge that can contribute for the reestablishment of this type of patient, is not mentioned in the consulted literature. The purpose of this dissertation was to characterize the muscle activity and the orofacial functions in patients, hospitalized at an Intensive Care Unit, with the clinical diagnosis of tetanus. Participants of this study were 13 patients hospitalized in the Intensive Care Unit of the Department of Infectious and Parasitic Diseases of the Clinical Hospital of the School of Medicine of the University of São Paulo with the diagnosis of tetanus, in the period of December 2005 and May 2007. The ages of the patients varied between 36 and 85 years, mean age of 53.69 years, being one female and twelve males. Patients were referred to a speech-language assessment during the phase of recovery. For this assessment, information contained in the medical charts, as well as a specific protocol for the assessment of dysphagia were used. This protocol is divided in two sections - examination of the oral-motor functions and clinical swallowing tests. This dissertation was divided in two studies. The first study had as a purpose to characterize the muscle activity and the orofacial functions, and to identify the clinical factors and/or swallowing tests that could be more related to this pathology. According to the results, most of the evaluated aspects were considered primarily altered. The clinical factor GAG Reflex and the elevation of the larynx during the clinical test of water were considered altered in all of the participants who could be assessed. The clinical factors of tongue movement and/or vocal changes were the aspects that presented correlation when comparing both stages of assessment. The second study had as a purpose to characterize, in clinical terms, the muscle activity and the orofacial functions and to determine aspects and/or alterations that could be considered common to this group of patients. The focus of tetanus which prevailed was that resulting from external and traumatic factors, the incubation period had as an average 7 days and the average of progression was of 1 day. All patients were intubated, used tracheostomy, used forms of sedation, used alternative forms of feeding and used mechanical ventilation. The clinical factors of tongue mobility, vocal quality and speech motor functions presented some type of alteration. The results of the study gave evidence to the orofacial myofuntional alterations already pointed in the literature as being related to patients with tetanus, as well as pointing new muscle and functional characterizations, pertinent to the Stomatognathic System, done by professionals with expertise in the field. The study allowed a better and greater possibility of direction in the assessment and treatment of this xiv group of patients, presenting a material that is associated to the symptoms and clinical signs through the process of standardized clinical evaluation.

The dissertation deals with the infant mortality decline in Iceland during the 19th and early 20th Century. It shows that despite its low degree of urbanization, pre-transitional Iceland displayed higher infant mortality rates than most other European countries. Levels are only comparable with a few areas in Europe, all of whom were known for a tradition of artificial feeding of newborns. In the Icelandic case, infants were either not breastfed at all or were weaned at a very young age. Another characteristic of infant mortality in Iceland were huge fluctuations during epidemics. Because of the isolation of the country, several diseases that had become endemie in other societies, such as measles, became dangerous epidemics in Iceland and affected all age groups. After 1850 the effects of epidemics declined and 20 years later there was a steep decline in infant mortality. By the beginning of the 20th Century infant mortality in Iceland was lower than in most other societies. Although epidemics often had important temporary consequences upon infant mortality level in pretransitional Iceland, being breastfed or not was without doubt the most important determinant of infant survival. There were huge differences in infant mortality levels between areas where breastfeeding was common and those where newborns were artificially fed. Towards the turn of the 20th Century significant changes occurred. Even though there were still differences in infant mortality between those babies who were breastfed and those who were not, infant survival had improved greatly and survival chances of Icelandic newborns that were fed artificially became in an international perspective relatively good. Midwives played a central role in the infant mortality decline in Iceland. Growing secularization during the second part of the 19th Century improved educational opportunities for women and also changed the content of education. Improved educational opportunities were reflected in changes in the education of midwives. At the same time there was growth in the publication of books that directly dealt with the issue of infant health. The increase in the number of educated midwives was a factor of central importance. The interaction between midwives and a literate population was most likely the key to infant survival in the Nordic countries. This study shows that that the custom to breastfeed spread earlier in areas with higher literacy. Not only is it plausible that the interest in changing prevailing traditions was directly related to literaey levels of individuai mothers, it is also shown that midwives had the best education in areas where literacy rates were high. On the other hand, the remarkable improvements in infant survival obtained towards the end of the 19th Century were scarcely linked to changes in the economic structure. Those factors only started to play an important role in the 20th Century. In its initial stages, changes in infant feeding and improvements in personal hygiene were more important / digitalisering@umu

Les exosomes sont des vésicules d'origine endocytaire sécrétées par les cellules dans leur environnement après fusion des endosomes multivésiculés avec la membrane plasmique. Ils représentent un nouveau moyen de communication cellulaire par le transfert intercellulaire de protéines, de lipides et d'ARN. Dans le laboratoire, nous nous intéressons aux rôles que pourraient jouer les exosomes neuronaux dans le système nerveux central. Nous avons montré que les neurones matures sécrètent des exosomes. Nous avons mis en évidence que cette sécrétion est directement reliée à l'activité synaptique glutamatergique et à une entrée de Ca2+. Nous avons également découvert que la partie C-terminale de la chaîne lourde de la toxine du tétanos peut être sécrétée par voie exosomale. Nous avons observé que les exosomes la contenant sont repris par des neurones en culture. Un tel cargo semble d'ailleurs influencer le devenir des exosomes. De plus, pour étudier la recapture des exosomes, nous avons utilisé des exosomes de cellules N2a exprimant la tétraspanine CD63 fusionnée à la GFP. En incubant des neurones d'hippocampe avec des exosomes GFP-CD63, nous sommes parvenus à démontrer qu'ils étaient endocytés par les neurones receveurs. Cependant, bien que les exosomes semblent avoir été internalisés, nos résultats suggèrent que leur trafic serait indépendant de la voie endocytaire classique. Enfin, nous nous sommes intéressé au contenu en ARN des exosomes de N2a et de neurones. Nous avons démontré qu'ils contenaient majoritairement des ARN courts (≤ 200 nucléotides) parmi lesquels, les microARN 132 et 138. Les microARN sont de puissants régulateurs de l'expression génique. Leur transfert, via les exosomes, représenterait une nouvelle voie de régulation très fine et avec un impact conséquent sur le fonctionnement du système nerveux. Les exosomes neuronaux pourraient donc jouer un rôle dans la physiologie normale de la synapse, en permettant l'échange d'ARN et de récepteurs aux neurotransmetteurs entre neurones. Ils pourraient également être impliqués dans la propagation de protéines pathogènes comme la toxine du tétanos et la propagation de certaines maladies neurodégénératives comme Alzheimer et Creutzfeldt-Jacob. L'ensemble de nos résultats suggère que les exosomes joueraient un rôle-clé dans le système nerveux central, de par leur implication dans des processus physiologiques et pathologiques. / Exosomes are vesicles of endocytic origin released by cells into their environment on fusion of multivesicular endosomes with the plasma membrane. They represent a novel mechanism of cell communication by intercellular transfer of proteins, lipids and RNAs. In our laboratory, we are interested in the roles neuronal exosomes could play in the central nervous system. We first showed that mature neurons secrete exosomes and that this is regulated by synaptic glutamatergic activity and by Ca2+ influx. We next demonstrated that the C-terminal part of the tetanus toxin heavy chain can be released in association with neuronal exosomes which can then be taken up by other neurons. Moreover, such a cargo seems to influence the actual fate of the exosome. In order to further examine exosome reuptake, we used exosomes from N2a cells expressing the tetraspanin CD63 fused to the green fluorescent protein, GFP. By incubating cultured hippocampal neurons with GFP-CD63 exosomes, we succeeded in proving that they were found inside the recipient neurons. However, although exosomes are internalized, our results suggest that their traffic is independent of the classical endosomal pathway. We also studied the RNAs contained in the N2a and neuronal exosomes. These were mainly short RNAs (≤ 200 nucleotides) including microRNAs 132 and 138. MicroRNAs are key regulators of gene expression. Their transfer by exosomes could represent a new way for fine regulation with a potentially powerful impact on the nervous system. Neuronal exosomes could play a crucial role in the normal physiology of synapses, by allowing the exchange of RNAs and neurotransmitter receptors between neurons. They could also propagate pathogenic proteins such as tetanus toxin and be involved in neurodegenerative disorders such as Alzheimer's and Creutzfeldt-Jacob's diseases. Altogether, our results pave the way towards the demonstration that exosomes play an important part in the functioning of the central nervous system via their involvement in physiological and pathological processes.

Trata-se de uma pesquisa com o objetivo de compreender o adoecimento pelo tétano neonatal, a partir da análise da trajetória de um grupo de 19 mães de crianças que morreram em conseqüência da doença no período compreendido entre 1997 e 2002, em municípios do Estado de Minas Gerais, Brasil. Para a análise, foram utilizadas Políticas de Assistência à Saúde da Mulher, Imunização e a Estratégia de Saúde da Família. Os dados foram obtidos em entrevistas semi-estruturadas e nos registros secundários do Cartão de Vacina e do Cartão da Gestante. A metodologia adotada foi de natureza quantitativa e qualitativa, com enfoque nas representações sociais sobre a experiência da doença e o risco de adoecimento. Para a análise das entrevistas, utilizou-se o instrumento do discurso do sujeito coletivo. As mulheres, em sua maioria, são multíparas em idade fértil, desconhecem a doença e seus mecanismos de prevenção, embora relatem as principais manifestações clínicas do tétano neonatal associando-o ao mal-de-sete-dias. São evidentes as práticas de tratamento inadequado do coto umbilical utilizadas pelas mulheres, sedimentadas no risco potencial para a doença, a irregularidade do pré-natal, a ausência ou a administração de doses insuficientes de vacina para a proteção do tétano neonatal e do tétano acidental, e procedimentos pós-parto domiciliar impróprios utilizados pelas parteiras ou curiosas. Observou-se, pelas falas das mães, a presença da crendice sobre os cuidados com o coto umbilical e a falha dos serviços no processo de educação para a saúde. Urge implementar esforços estratégicos específicos, direcionados à vigilância epidemiológica, à capacitação de parteiras e aos profissionais de saúde, incrementar serviços de pré-natal e ampliar a cobertura vacinal para as mulheres, principalmente nas regiões de onde provêm os casos da pesquisa, contribuindo, assim, para a eliminação da doença. / This research aimed to understand the illness caused by neonatal tetanus, based on the analysis of a group of 19 mothers’ histories involving children who died of the disease in communities located in the State of Minas Gerais, Brazil, between 1997 and 2002. The analysis was based on Women’s Health Care and Immunization Policies and the Family Health Strategy. Data were collected through semistructured interviews and secondary records from the Vaccination Card and the Pregnant Woman’s Card. A quantitative and qualitative methodology was adopted, focusing on the social representations about the disease experience and the risk of getting ill. The interviews were analyzed on the basis of collective subject discourse. Most women were of fertile age and multiparous and did not know about the disease and its prevention mechanisms, although they reported on the main clinical signs of neonatal tetanus, associating it with the “seven-day disease”. This study revealed the women’s use of inadequate practices for treating the umbilical cord stump, based on the potential risk of catching the disease, irregular antenatal treatment, the absence or administration of insufficient doses of the vaccine to protect against neonatal and accidental tetanus, and inappropriate post-home delivery procedures used by midwifes. The mothers’ discourse revealed the presence of popular beliefs on care related to the umbilical cord stump and the services’ deficiency in the health education process. There is an urgent need to implement specific strategic efforts, aimed at epidemiological supervision, the training of midwifes and health professionals, and to increase prenatal services and expand vaccination coverage for women, mainly in the research cases’ regions of origin, thus contributing to the elimination of this disease.

Temporal lobe epilepsy is the most common form of epilepsy and hippocampal sclerosis represents the main underlying structural abnormity. Approximately 20% of TLE cases are non- lesional due to absence of any obvious epileptogenic lesion and tetanus toxin model is traditionally considered as a model of non-lesional temporal lobe epilepsy. The main aim of this study was to evaluate the presence of the cell damage and to determine its spatiotemporal profile. Tetanus toxin was stereotaxically injected into CA3 subregion of dorsal hippocampus in adult male Wistar rats. Brain tissue was extracted 4, 8 and 16 days following the surgery. Postfixed brains were sectioned to 50 µm slices and labeled using Nissl's and FluoroJade B staining (FJB). Hippocampal sclerosis was present only in animals from D16 group, however, it was localized mainly in contralateral CA1 area. Additional finding was decreased Nissl's staining in contralateral hippocampus which corresponded with the presence of FJB positive neurons. In animals from group D8, we have identified presence of FJB positive neurons predominantly in ipsilateral hippocampus. In D4 animals, cellular degeneration was absent. To examine the non- lesional nature of tetanus toxin model, we have performed blind study, when Nissl's staining were reviewed...