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Les cellules sensorielles auditives, les cellules ciliées internes (CCI), transforment les ondes sonores en message nerveux. Les synapses des CCI se distinguent de celles du système nerveux par leur anatomie. En effet, les synapses des CCI sont dotées d'un organite appelé ruban synaptique. Ce dernier a pour fonction de concentrer les vésicules synaptiques à proximité des zones actives. Il est important de souligner qu'un déficit de la libération synaptique à la première synapse auditive est à l'origine de surdités chez l'homme. Si la physiologie des synapses à rubans des cellules ciliées a été intensivement étudiée, la composition moléculaire des ces synapses reste en grande partie inconnue. L'objectif de cette thèse était donc d'isoler les protéines clefs de la machinerie synaptique. Pour ce faire, nous avons utilisé la technique du double hybride à partir d'une banque d'ADN complémentaire de cochlée et de la protéine Ribeye, composant majeur des rubans, comme appât. La difficulté majeure de notre étude provient de la structure de Ribeye, qui est constitué par deux domaines A et B. Tandis que le domaine A est dirigé vers le cœur du ruban synaptique et aurait une fonction structurale, le domaine B est fortement homologue au facteur de transcription Ctbp2. Ainsi, nous avons identifié plusieurs candidats comme étant des facteurs de transcription. Ces derniers interagissent probablement avec Ctbp2 dans le noyau. Nos résultats obtenus soulignent la difficulté d'identifier des protéines d'interactions, inhérente à l'utilisation de Ribeye comme appât. Parmi les autres candidats, nous avons isolés des composants du système de l'ubiquitine, suggérant une régulation ubiquitine-dépendante de l'activité ou de la structure des rubans synaptiques. / Inner hair cells (IHCs) are the sensory cells of the cochlea, the organ of hearing. IHCs transduce sound stimulation into the release of glutamate onto the afferent auditory nerve fibers. To achieve this task, IHCs harbor at their presynaptic side a large organelle, the so-called synaptic ribbon, surrounded by a monolayer of glutamate-filled synaptic vesicles. Exocytosis of glutamate at the hair cell ribbon synapse seems to be unconventional as the synaptic machinery, depicted so far, differs from most of the nervous system synapses. The goal of this work was to identify new members of the synaptic machinery of the hair cell ribbon synapse. To do so, we took advantage of the yeast two-hybrid system using a cochlea cDNA library as the prey and Ribeye (the major ribbon component) as the bait. Transcription factors were highly represented in our screening assay, most probably because Ribeye is highly homologous to the transcription factor Ctbp2. They probably interact with Ctbp2 in the nucleus. Our results underlined the difficulty to identify protein interactions because of the nature of Ribeye itself. However, we found ubiquitin system components among the other candidates, suggesting an ubiquitin-dependent regulation of the activity and/or structure of synaptic ribbons.

Orientadores: Paulo César Giraldo, Angélica Espinosa Barbosa Miranda / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T14:22:13Z (GMT). No. of bitstreams: 1 Piassarolli_VirginiaPianessole_D.pdf: 3263446 bytes, checksum: f4dd848409151c430a17771f37ef8dd8 (MD5) Previous issue date: 2014 / Resumo: A higiene é o conjunto de cuidados corporais, do ambiente e de um modo de viver, de se vestir e de habitar para evitar doenças com o objetivo de conservar e fortificar a saúde. Em se tratando de saúde genital, a relação não poderia ser outra, uma vez que esta é parte integrante e inseparável da saúde geral do indivíduo. Estas ações são dependentes da condição social da população e previnem complicações e desconfortos, especialmente na área genital feminina, porém ainda não foram bem estudadas. Objetivo: Avaliar hábitos de higiene e cuidados com a genitália de mulheres no menacme e associá-los com fatores sociodemográficos. Sujeitos e Métodos: Foi realizado um estudo de corte transversal de base populacional, por amostragem, em todas as 28 Unidades de Saúde de Vitória, Espírito Santo, Brasil. Foram incluídas aleatoriamente 474 mulheres, admitidas em seus domicílios, no período de Julho de 2012 a Dezembro 2013. Um questionário auto-respondido foi preenchido de maneira sigilosa contendo 56 perguntas relacionadas ao tema, divididas nos seguintes domínios: I ¿ Limpeza genital; II ¿ Uso de absorventes higiênicos; III ¿ Práticas depilatórias; IV ¿ Uso de piercings e tatuagens genitais; V ¿ Tipo de Indumentária e VI ¿ Práticas sexuais. Além das variáveis relacionadas à higiene, foram considerados fatores sociodemográficos como idade, nível de escolaridade e renda familiar mensal, e algumas variáveis clínicas. A análise dos dados empregou o teste exato de Fisher para averiguar associação entre as variáveis; e regressão múltipla logística para verificar a chance de complicações clínicas e ginecológicas. O nível de significância considerado foi p<0,05. Resultados: A média da idade das participantes foi de 31 anos (± 7,7), 54% eram não caucasianas, casadas ou com parceiros (56,8%), com renda familiar inferior a R$ 1500,00 (53,7%) e 69,6% haviam cursado até o Ensino Médio. As análises sobre os hábitos de higiene demonstraram que 57,4% das mulheres tomavam dois banhos por dia, entretanto 51% lavavam a vulva mais de três vezes ao dia. O uso de lenços umedecidos foi relatado por 13,5% e somente 17,9% das entrevistadas realizavam corretamente a higiene após evacuação. Ducha vaginal foi descrita por 47% dos casos, quase 20% faziam esfoliação na região vulvar e 44,5% relataram corrimento vaginal frequentemente. O uso frequente do protetor diário ocorreu em 38,9% da população, entretanto somente 40,7% destas usavam o protetor sem película plástica. Mulheres mais jovens (p<0,0001) e com maiores níveis de escolaridade (p=0,0390) usavam menos absorventes internos. Observou-se que quanto maior a troca diária do número de absorventes durante o período menstrual, menor foi a chance de aparecimento de fissuras como complicação [OR=0,11 (IC95%:0,02-0,48)]. Quanto ao uso de vestimentas, o tipo de calcinha menos utilizada foi a sintética (5,5%) e os modelos fio dental ou tanga foram os mais relatados (68,6%), principalmente entre as mais jovens (p<0,0001). Cerca de metade da amostra referiu o uso frequente de calças apertadas (51,1%), o que esteve associado às mulheres jovens (p=0,0002) e com maior nível de escolaridade (p=0,0173), além de ser uma variável que identificou uma chance quase duas vezes maior do aparecimento de corrimento vaginal relatado pelas participantes [OR=1,95 (IC95%:1,35-2,81)]. Verificou-se que 97,9% das mulheres realizavam depilação íntima e 65,4% acreditavam ser importante para higiene. Em geral, mulheres com baixa escolaridade e renda utilizavam a lâmina de barbear como principal método. A depilação genital de forma "completa" foi relatada por 52,1% das participantes. Conclusão: Os hábitos de higiene e cuidados com a genitália ainda são inadequados em um percentual muito elevado de mulheres brasileiras. Fatores sociodemográficos como idade, nível de escolaridade e renda familiar mensal associaram-se com diversos aspectos na prática destes hábitos / Abstract: Hygiene is the set of body care, of the environment and a way of living, dressing and inhabits to prevent diseases with the goal of preserving and strengthening the health. In terms of genital health, the relation could not be different, since this is an integral and inseparable part of the overall individual health. These actions are dependent on the social status of the population and prevent complications and discomfort, especially in the genital area, but have not been well studied. Objective: To evaluate hygiene and care genitalia among women in menacme and associate them with sociodemographic factors. Subjects and methods: A population-based study was conducted, by sampling at all 28 health units in Vitoria, Espirito Santo, Brazil. Randomized 474 women were included, admitted in their homes between July 2012 to December 2013. A self-administered questionnaire was completed confidentially containing 56 questions related to the subject, divided into the following areas: I - Genital cleaning; II - Use of sanitary pads; III - Depilatory practices; IV - Use of genital piercings and tattoos; V -Clothing type and VI - Sexual practices. Apart from hygiene-related variables were considered sociodemographic factors such as age, education level and monthly family income, and some clinical variables. Fisher Exact Test was used to assess associations between variables; and multiple logistic regression to verify the chance of gynecological and clinical complications. Significance level was set at p <0.05. Results: The average age of participants was 31 years (± 7.7), 54% were not caucasian, married or had partners (56.8%), with family income less than R $ 1500.00 (53.7%) and 69.6% had attended high school. Analyses of hygiene habits showed that 57.4% of women took two baths per day, however 51% washed the vulva more than three times daily. The use of wet wipes was reported by 13.5% and only 17.9% of respondents performed correctly hygiene after defecation. Vaginal douching was reported by 47% of cases, almost 20% did exfoliation in vulvar region and 44.5% reported vaginal discharge frequently. The frequent use of the panty liners occurred in 38.9% of the population, however only 40.7% of these used without plastic layer. Younger women (p<0.0001) and with higher levels of education (p = 0.0390) used less tampons. It was observed that the greater the number of daily change of the absorbent during the menstrual period, the lower chance of appearance of fissures as genital complication [OR=0.11 (CI95%:0.02-0.48)]. Regarding the use of clothes, the type of underwear was less synthetic (5.5%) and the models thong or string were the most common (68.6%), especially among the youngest (p<0.0001). Approximately half of the sample reported frequent use of tight pants (51.1%) which was associated with young women (p=0.0002) and higher educational level (p=0.0173), as well as being a variable which identified almost twice the chance of appearance of vaginal discharge reported by participants [OR=1.95 (CI95%:1.35-2.81)]. It was verified that 97.9% of women performed pubic hair removal and 65.4% did because they believe it is important for hygiene. Generally, the razor blade was the main method used by women with low education and income. The "complete" genital hair removal was related by 52.1% of participants. Conclusion: Hygiene habits and genitalia care are still inadequate in a very high percentage of Brazilian women. Sociodemographic factors such as age, education level and monthly family income were associated with several aspects in practice of these habits / Doutorado / Fisiopatologia Ginecológica / Doutora em Ciências da Saúde

Notre capacité à communiquer et à apprécier la musique repose sur une discrimination de fréquences couvrant une large gamme de fréquences sonores. Cette propriété résulte de cellules mécanosensorielles « ciliées », qui sont réglées pour répondre de façon maximale à une fréquence caractéristique qui varie monotoniquement le long de l’axe de l’organe auditif, la cochlée. Les mécanismes cellulaires et moléculaires qui définissent la fréquence d’une cellule ciliée et régulent sa valeur pour différentes cellules afin de couvrir la gamme auditive demeurent néanmoins inconnus. Notre hypothèse de travail est que cette fréquence est réglée en partie par les propriétés mécaniques passives et actives de la « touffe ciliaire », l’antenne mécanosensorielle de la cellule ciliée. A l’aide d’une préparation excisée de la cochlée du rat, nous avons combiné l’iontophorèse de chélateurs de calcium (BAPTA ou EDTA) pour casser les liens de bout-de-cil qui connectent les stéréocils voisins de la touffe ciliaire, une stimulation grâce à un micro-jet de fluide pour estimer la raideur de la touffe ciliaire et des enregistrements en « patch-clamp » de courants de transduction afin de compter le nombre de liens de bout-de-cil intacts qui contribuent à la réponse. Avec les mouvements évoqués par la rupture des liens de bout-de-cil et avec nos mesures de raideur, nous avons pu estimer la tension dans toute la touffe ciliaire, ainsi que la tension dans un seul lien de bout-de-cil en connaissant le nombre de liens qui contribuent à cette tension. Dans les cellules ciliées externes, qui sont impliquées dans l’amplification du stimulus sonore mais qui n’envoient pas d’information neuronale au cerveau, nous avons observé un gradient de tension et de raideur lorsque la fréquence caractéristique de la cellule ciliée augmente, suggérant que ces paramètres physiques peuvent être impliqués dans le réglage d’une cellule ciliée à sa fréquence caractéristique. Au contraire, pour les cellules ciliées internes, les vraies cellules sensorielles de la cochlée, nos observations ne montrent pas de gradient significatif. De plus, nous avons observé des mouvements de la touffe ciliaire induits par la variation de la concentration en calcium, correspondant à une tension accrue pour des concentrations en calcium plus faibles. Ces mouvements sont similaires à ceux évoqués dans d’autres classes de vertébrés, tels que chez la grenouille ou chez la tortue. Ainsi, nos résultats réconcilient les expériences faites chez les vertébrés inférieurs et chez le mammifère, et montrent l’implication des gradients de la mécanique de la touffe ciliaire pour l’importante sélectivité fréquentielle de la cochlée / Our ability to communicate and appreciate music relies on acute frequency discrimination over a broad range of sound frequencies. This property results from the operation of mechanosensory “hair" cells, which are each tuned to respond maximally to a characteristic frequency that varies monotonically along the axis of the auditory organ, the cochlea. The cellular and molecular mechanisms that set the characteristic frequency of a hair cell and regulate its value among different cells to cover the auditory range have remained elusive. Our working hypothesis is that tuning results in part from passive and active mechanical properties of the “hair" bundle, the mechanosensory antenna of the hair cell.Using an excised preparation from the rat cochlea, we combined iontophoresis of a calcium chelator (BAPTA or EDTA) to break the tip links that interconnect neighbouring stereocilia of the hair-cell bundle, fluid-jet stimulation to estimate hair-bundle stiffness and patch-clamp recordings of transduction currents to count the number of intact transduction channels contributing to the response. From the movements evoked by tip-link breakage and our stiffness measurements, we were able to estimate tension in the whole hair bundle as well as, knowing the number of tip links contributing to this tension, in a single tip link.In outer hair cells, which are involved in sound amplification but do not send neural information to the brain, we observed a gradient of tension and stiffness from the low-frequency to the high-frequency end of the cochlea, suggesting that these physical parameters may help tune the hair cell to its characteristic frequency. Interestingly, with inner hair cells - the true sensors of the cochlea, our observations do not show any significant gradient. Furthermore, we observed calcium-evoked hair-bundle movements corresponding to an increased tension in the tip links at decreased concentrations of calcium. These movements were similar to those evoked in other classes of vertebrates, such as the frog or the turtle. Together, our results reconcile experiments performed in lower vertebrates with those performed in mammals and show the implication of hair-bundle mechanical gradients in the sharp frequency tuning of the cochlea

Somatosensory neurons densely innervate skin, our largest sensory organ. Adult skin continually remodels throughout the lifespan to maintain a protective barrier for our bodies. How sensory neurons maintain their peripheral endings in the face of continual turnover of their target tissue is not well understood. To address this gap in knowledge, I analyzed the temporal dynamics and mechanisms of structural plasticity of touch receptors in healthy adult skin. My studies focused on the terminals of Merkel-cell afferents in mouse touch domes. These two-part touch receptors comprise epithelial Merkel cells innervated by branching axons of fast-conducting sensory neurons. I show that Merkel cells and their afferents are structurally plastic over the course of hair growth in adults. These two components simplify during active hair growth, with fewer terminal neurites and fewer Merkel cells per touch dome at this stage compared with other phases of hair growth. Merkel-cell removal was observed with multiple molecular markers. Additionally, mice showed diminished touch-evoked behavior during hair growth compared with follicle quiescence. Next, I showed that Sarm1, a key effector of Wallerian degeneration, is not required for structural plasticity of Merkel cell-neurite complexes in young adulthood. Finally, I developed a technique to perform time-lapse in vivo imaging of identified Merkel cells and afferent terminals over the course of a month. These structures were highly plastic, with afferent terminals undergoing frequent growth and regression, as well as both Merkel cells and terminal branches being added or removed. Together, these studies reveal that peripheral nerve terminals undergo a previously unsuspected amount of structural plasticity in healthy tissue.

In the amphibian auditory system, a subset of hair cells is known to be frequency tuned via electrical resonance. This tuning is thought to contribute to frequency selectivity of the information leaving the auditory periphery via the auditory afferent fibers. At the same time, while most, if not all, afferent fibers are shown to be frequency tuned, electrical resonance has only been experimentally demonstrated in a subset of amphibian auditory hair cells. In this thesis, we validate and use a novel Zap current method to probe the electrical resonance of the bullfrog amphibian papilla hair cells. We uncover the existence of two previously unknown types of electrically resonant auditory hair cells. We then show the existence of resonant hair cells across the length of amphibian papilla, with the range of frequency tuning that is nearly indistinguishable from that previously reported in the of auditory fibers. Therefore, this work further validates amphibian hair cell frequency resonance as the possible mechanism underlying frequency selectivity of the subsequent stages in auditory signal transduction.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23094号 / 医博第4721号 / 新制||医||1050(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 髙橋 良輔, 教授 井上 治久, 教授 伊佐 正 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Content: Fine hair is the biggest seasonal challenge for bovine leather production in the United States. The origin, timing and severity of the fine hair problem can be unpredictable and vary from year to year. Seasonal changes on the hair growth cycle are prompted by the lower temperature from fall to winter; the cow hair increases in amount, length and thickness. This problem is very old and has increased in intensity due to changes in the leather manufacturing process, cattle breeding conditions and breed diversity. The amount of fat and thickness of the hide also play important roles. The extent of the problem has not been documented and is not fully understood by the scientific community. The presence of fine hair (residual hair) on the wet blue and final leather are a cause of downgrading the leather. If the wet blue has fine hair, it cannot be removed in further processing in crust or finishing. Some leather types can tolerate more fine hair than others. In this paper we will conduct a scientific evaluation of the fine hair on American bovine hides, wet blue and finished leathers through cross sections and stains, optical and electron microscope observations. We will include measurements of hair thickness and hair depth inside the hide. The work will compare sulfide and oxidative unhairing of winter hides, characterize and show the details of the fine hair through cross sections, and offer indicative measures to minimize the problem. Information from the largest wet blue manufacturer in the US with four tanneries will provide insight on the fine hair seasonality, types of breeds and cattle displacement temperature ranges and will discuss adaptive changes needed in the “Winter” time to control the fine hair. Take-Away: 1) scientific review and evaluation of the problem of fine hair though cross sections and stains, optical and electron microscopy observations 2) evaluate the fine hair on sulfide and oxidative unhairing; providing indicative measures to minimize the problem 3) characterize the seasonality of the fine hair problem regarding the types of breeds, displacement temperature ranges and adaptative changes to control the fine hair

This master thesis focuses on the theme of a rite of passage, of a pupil turning into a master. It is about the material and mental change during a performance in the space of a baroque chapel. In this way, a man´s spirit and the genius loci of a place are interconnected.

Topic of this thesis is to create a practicable business plan for foundation e-shop with hair. Specifically, the hair used for extensions. Company will be founded as limited liability company. The theoretical part deals with setting up company and creating business plan.