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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
441

Produção e avaliação de vetores retrovirais visando à diferenciação de neurônios olfativos in vitro pela superexpressão de fatores de transcrição definidos / Production and evaluation of retroviral vectors for the differentiation of olfactory neurons in vitro by over-expression of defined transcription factors

Tolentino, Felipe Thadeu, 1983- 24 August 2018 (has links)
Orientador: Fabio Papes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T14:16:00Z (GMT). No. of bitstreams: 1 Tolentino_FelipeThadeu_M.pdf: 9244448 bytes, checksum: deea9f7963e05d8a997d9b5a554f9708 (MD5) Previous issue date: 2014 / Resumo: O Sistema Sensorial Olfativo de mamíferos é composto por vários subsistemas na cavidade nasal. Dentre estes, destacam-se o sistema olfativo principal e o sistema olfativo acessório ou vomeronasal. O primeiro realiza a detecção geral de odores e parece participar também da detecção de algumas substâncias que levam a respostas comportamentais instintivas (feromônios), enquanto o último é especializado na detecção desta classe de semioquímicos. A detecção dos estímulos sensoriais olfativos resulta em informações importantes que dependem de vias complexas para sua interpretação e para a geração de respostas apropriadas por parte do sistema nervoso central. Existem vários pontos ainda desconhecidos sobre o funcionamento do sistema olfativo, tanto no que diz respeito aos mecanismos moleculares subjacentes à escolha dos receptores a serem expressos por um dado neurônio sensorial ¿ sendo que cada neurônio olfativo expressa apenas um receptor dentro de uma grande família multi-gênica ¿ quanto em relação ao processamento da informação sensorial em centros cerebrais superiores. Neurônios sensoriais olfativos cultivados eficientemente in vitro seriam extremamente úteis, pois poderiam ser utilizados como ferramenta para o estudo destes problemas, como a investigação da atividade das células sensoriais olfativas, possibilitando, por exemplo, uma melhor compreensão dos mecanismos genéticos e moleculares por trás da expressão dos receptores olfativos e de suas propriedades de detecção. Neste trabalho foram desenvolvidas ferramentas baseadas em vetores retrovirais com o objetivo de induzir a diferenciação celular de neurônios olfativos in vitro, utilizando uma combinação de fatores de transcrição, por meio de transdução viral em células-alvo (fibroblastos murinos). Os retrovírus produzidos foram testados e algumas combinações de fatores de transcrição foram preliminarmente testadas, sendo capazes de induzir mudanças moleculares em fibroblastos acompanhadas da expressão de marcadores de neurônios sensoriais olfativos / Abstract: The mammalian Olfactory System enables the vast majority of animal species to identify the presence and quality of food, predators, competitors, conspecifics and potential mates in the environment. Olfactory stimuli detected by sensory neurons are interpreted by brain processing pathways to generate appropriate behavioral and endocrine responses. Despite its central importance in mammalian physiology, several aspects about the biology of this sensory system remain uncharacterized. For example, it is known that each olfactory sensory neuron (OSN) in the nasal cavity expresses only one gene out of a large multi-gene family coding for receptors involved in odorant and pheromone detection. However, the molecular mechanisms behind this process of olfactory receptor gene choice are not fully understood. The study of this and many other aspects of olfaction has been made difficult by the lack of appropriate in vitro cellular models. An efficient way to obtain cultured OSNs would thus be extremely useful, enabling researchers to investigate the sensory neuron¿s activity in a controllable environment, avoiding obstacles imposed by the cellular heterogeneity found in sensory organs in vivo. In this study, we aimed at obtaining OSNs directly differentiated from mouse embryonic fibroblasts (MEF) using the forced expression of specific transcription factors via retroviral vectors. We therefore developed tools based on retroviral vectors with the objective of differentiating olfactory sensory neurons in vitro, using viral transduction in target cells (murine fibroblasts) with combinations of select transcription factors. Retroviruses were tested and some combinations of transcription factors were tested on a preliminary basis, which were capable of inducing molecular alterations on fibroblasts followed by the expression of olfactory sensory neuron markers / Mestrado / Genetica Animal e Evolução / Mestre em Genética e Biologia Molecular
442

Social Agent: Facial Expression Driver for an e-Nose

Widmark, Jörgen January 2003 (has links)
This thesis describes that it is possible to drive synthetic emotions of an interface agent with an electronic nose system developed at AASS. The e-Nose can be used for quality control, and the detected distortion from a known smell sensation prototype is interpreted to a 3D-representation of emotional states, which in turn points to a set of pre-defined muscle contractions. This extension of a rule based motivation system, which we call Facial Expression Driver, is incorporated to a model for sensor fusion with active perception, to provide a general design for a more complex system with additional senses. To be consistent with the biologically inspired sensor fusion model a muscle based animated facial model was chosen as a test bed for the expression of current emotion. The social agent’s facial expressions demonstrate its tolerance to the detected distortion in order to manipulate the user to restore the system to functional balance. Only a few of the known projects use chemically based sensing to drive a face in real-time, whether they are virtual characters or animatronics. This work may inspire a future android implementation of a head with electro active polymers as synthetic facial muscles.
443

Interactions entre rythmes rapides et rythmes lents dans la représentation de l’information olfactive dans le réseau bulbaire / Fast and slow rhythms interactions in olfactory information representation in bulbar network

Cenier, Tristan 03 July 2009 (has links)
Une particularité de la modalité sensorielle olfactive est la nature complexe du stimulus chimique à représenter. Les cellules sensorielles de la cavité nasale sont sensibles aux traits physico-chimiques des molécules et transmettent cette information vers le bulbe olfactif, premier relais central de cette modalité. L’organisation des voies de projection vers le bulbe entraîne une spatialisation de l’activité dans cette structure, ce qui constitue un mode de représentation de l’information mais qui n’est pas suffisant à lui seul. Le bulbe olfactif est également marqué par des phénomènes dynamiques prépondérants. Tout d’abord le rythme respiratoire, qui organise temporellement le niveau d’activation de l’appareil sensoriel, ensuite les oscillations des potentiels de champs locaux, et enfin les oscillations sous-liminaires des potentiels de membrane des cellules. Ces éléments dynamiques pourraient être le support de la formation d’assemblées de neurones, sous-populations de cellules synchronisées transitoirement et permettant la représentation de l’information suivant un principe spatio-temporel. Les travaux présentés dans cette thèse sont basés sur l’enregistrement conjoint des activités unitaires des cellules du bulbe, des oscillations des potentiels de champs locaux et de la respiration en réponse à des stimulations olfactives. Nous montrons les relations existant entre les différents phénomènes dynamiques et comment ils permettent d’organiser l’activité des cellules pour aboutir à la formation d’assemblées de neurones fonctionnelles. Nous mettons particulièrement en évidence le rôle central de la respiration dans le fonctionnement intégré du bulbe olfactif. / A striking feature of the olfactory sensory system is its ability to deal with a complex multi-dimensional chemical stimuli. Receptor cells in the nasal cavity are sensitive to specific features of molecules and transmit this information to the olfactory bulb, first relay for olfaction in the central nervous system. Due to the organization of projection pathways to the bulb, afferent information activates the structure in a topographical fashion ; although this may constitute a coding strategy for olfactory information it has proven insufficient, and other strategies must be investigated. Dynamic phenomenons are a preponderant feature of the olfactory bulb. The respiratory rhythm imposes a sinusoidal level of activation to the system, oscillations in local field potentials and subthreshold oscillations in neurons membrane potentials may interact and lead to the transient synchronization of sub-populations of neurons. This particular mechanism, designated as neural assemblies, is in theory a good candidate for the representation of olfactory information. The work presented here is based on conjoint recordings, in anesthetized animals, of unitary activities, oscillations in the LFP and respiration, in response to olfactory stimulation. We show the relationships existing between the various dynamic phenomenons, and hypothesize on their functional roles. We propose that a same mechanism may form different neural assemblies each assuming a specific functional role. The respiratory rhythm acts as a gating system, organizing the formation of successive yet different neural assemblies.
444

Universalité et diversité de la perception olfactive humaine : approches psychophysique, moléculaire et neurobiologique / Universality and diversity of the human olfactory perception : psychophysical, molecular and neurobiological approaches

Sezille, Caroline 08 October 2014 (has links)
Dans une société allant de l'avant et voulant couper avec son côté animal, la perception olfactive a été jugée inutile et limitée à sa plus simple expression. Il n'est donc pas étonnant que la perception olfactive soit une des dimensions de notre univers sensoriel les plus difficiles à appréhender. Cette thèse de doctorat étudie la perception des odeurs chez l'Homme. La recherche s'est centrée sur deux aspects importants de l'odorat : la valence hédonique de l'odeur (son caractère agréable ou désagréable) et la qualité de l'odeur (par exemple, son caractère floral ou fruité). L'olfaction a également pour caractéristique d'être très variable d'un individu à l'autre. En effet, bien que certaines odeurs soient perçues de la même manière par la majorité de la population, de nombreuses autres sont perçues de manière très différente entre individus. Ainsi, le principal objectif de la thèse a été d'apporter des éléments d'explication des facteurs déterminant la variabilité interindividuelle dans la perception qualitative et hédonique des odeurs. Sans aller jusqu'à une explication totalement déterministe selon laquelle la perception olfactive serait « inscrite dans la molécule », les résultats de cette thèse renforcent ainsi l'idée que la perception hédonique et qualitative de l'odeur est construite à travers une hiérarchie de traitements débutant par l'association d'une structure moléculaire bien précise (ou d'un attribut particulier) et d'un ensemble de récepteurs olfactifs. L'expression différentielle de ces récepteurs olfactifs selon les individus et les populations, ainsi que l'apprentissage par simple exposition ou par acquisition d'une expertise, coloreront alors de manière personnelle la valence et la qualité perçue des odeurs, conduisant ainsi à une hétérogénéité interindividuelle en matière de perception olfactive / In a society moving forward and wanting to cut with his animal side, olfactory perception has been judged unnecessary and limited to its simplest expression. Unsurprisingly, olfactory perception was found to be one of the most difficult dimensions to understand in our sensory universe. This dissertation examines the perception of odors in humans. The research effort has been focused on two important aspects of smell: the hedonic valence of odor (ie the pleasantness or unpleasantness of the sample) and odor quality (eg, its floral or fruity note). Olfaction is also known to be highly variable from one individual to another. Indeed, although some odors are perceived in the same way by the majority of the population, many others are perceived very differently between individuals. Thus, the main objective of the research was to provide some explanation on important factors of inter-individual variability in the qualitative and hedonic perception of odors. Without making the complete deterministic claim that olfactory perception is "written in the molecule", the results in this dissertation reinforce the idea that the hedonic and qualitative perceptions of smell are built through a hierarchy of treatments starting with the combination of molecular structure (or of a particular structural attribute) and a very specific set of olfactory receptors. The difference in expression of these olfactory receptors as individuals and populations, as well as learning by mere exposure or acquisition of expertise will then color in a personal way the valence and perceived quality of odors, leading to inter-individual heterogeneity in olfactory perception
445

Effets promnésiants de l'activation des récepteurs sérotoninergiques de type 4 (5-HT4) dans des modèles rongeurs (rats, souris) de vieillissement normal et pathologiques

Jacquet, Marlyse 02 December 2014 (has links)
Chez les rongeurs, la mémoire procédurale est préservée alors que la mémoire « déclarative » est profondément altérée au cours du vieillissement normal ou pathologique.L’injection d’un agoniste partiel des récepteurs 5-HT4 (SL 65.0155. 0.01mg/kg) permet aux rongeurs de récupérer leurs facultés dans une tâche de discrimination olfactive, le labyrinthe olfactif par exemple.L’activation des récepteurs 5-HT4 par un agoniste pourrait être utilisée pour lutter contre les dysfonctionnements mnésiques rencontrés dans certaines pathologies neurodégénératives telle que la maladie d’Alzheimer. L’injection d’un agoniste partiel des récepteurs 5-HT4 (SL 65.0155. 0.01mg/kg) permet aux rongeurs de récupérer leurs facultés dans une tâche de discrimination olfactive, le labyrinthe olfactif par exemple.L’activation des récepteurs 5-HT4 par un agoniste pourrait être utilisée pour lutter contre les dysfonctionnements nésiques rencontrés dans certaines pathologies neurodégénératives telle que la maladie d’Alzheimer. / In normal aging or pathological brain diseases in rodents procedural memory is spared while reference memory is deeply impaired.Injection of a partial selective 5-HT4 agonist (SL65.0155. 0.01mg/kg) enabled complete recovery of association learning performance in an olfactory associative discrimination task, the olfactory tubing maze for exemple.Activation of 5-HT4 receptors by a selective agonist could be useful for the symptomatic treatment of memory dysfunctions related to pathological aging such as Alzheimer’disease.
446

La perception sensorielle des bébés nés à terme et prématurés / The sensory perception of term-aged preterm and full-term infants

André, Vanessa 18 December 2017 (has links)
La perception sensorielle est propre à chaque individu. Elle découle du patrimoine génétique (qui définit les récepteurs sensoriels), mais varie en fonction de la maturation et de l’expérience d’un individu. En ce sens, l’étude du bébé nous a permis de tester à la fois 1) l’effet de la maturation, en comparant la perception des bébés avec celle des adultes et 2) l’effet de l’expérience sensorielle précoce, en comparant la perception sensorielle de bébés nés à terme ou prématurés pour un même âge donné. Nos résultats ont souligné une perception sensorielle plus étendue chez le bébé que chez l’adulte, via la perception de stimulations tactiles très fines ou encore la perception d’ultrasons, qui ne sont plus perçus à l’âge adulte. Les mécanismes de maturation des organes sensoriels et de « recentrage sensoriel » envers les stimulations pertinentes, pouvant intervenir au cours du temps, ont été présentés. Nous avons également montré une réactivité particulièrement marquée des bébés prématurés, en comparaison avec les bébés nés à terme. Différents mécanismes sous-jacents potentiels tels qu’une adaptation de la sélectivité neuronale aux stimulations environnementales, une plasticité cérébrale conservée/retardée, ou encore le développement d’une hypersensibilité ont été discutés. En sus du cœur de cette thèse, nous nous sommes intéressés à l’ « Umwelt » social du bébé, en étudiant 1) ses capacités de perception et de discrimination des odeurs corporelles humaines et 2) sa capacité à s’exprimer sur sa perception sensorielle. Nous avons montré que le bébé est un être très réceptif à son monde social, capable de discriminer entre les odeurs de ses partenaires sociaux. De plus, le bébé est également très expressif sur sa perception sensorielle, notamment via l’utilisation d’un répertoire vocal complexe (au-delà des pleurs), dont certains types de vocalisations pourraient refléter son état de confort ou d’inconfort. Les résultats de cette thèse ouvrent de nombreuses pistes de réflexion en termes d’adaptations des pratiques néonatales. / Sensory perception is specific to each individual. It results from the gene pool (which defines the sensory receptors), but varies depending on maturation and experience. In this sense, the study of babies has enabled us to test both 1) the effect of maturation by comparing the babies’ sensory perception to those of adults and 2) the effect of early stage sensory perception by comparing the sensory perception of preterm and full-term infants at a same post-conception age (i.e. term-aged infants). Our results underlined a larger sensory perception in babies than in adults, through the perception of very subtle tactile stimulations, or else the perception of ultrasounds, that cannot be perceived by grown-ups. The mechanisms of the maturation of sensory organs and of ‘’sensory recentering‘’ towards relevant simulations that can happen in the course of time have been presented. We have also shown a particularly strong reactivity of preterm babies in comparison to full-term babies. Various potential subjacent mechanisms such as a neuronal selectivity adaptation to environmental stimulations, a maintained/ delayed cerebral plasticity or else the development of a hypersensitivity have been discussed. In addition to the core of this thesis, we have taken an interest in the baby’s social “Umwelt” and have studied 1) his abilities in perception and discrimination between human body odours and 2) his ability to express his sensory perception. We have shown that babies are very responsive to their social world, capable of discrimination between different social partners’ odours. Furthermore, babies also are highly expressive when it comes to their sensory perception, especially through the use of a complex vocal repertoire (beyond cries/tears). Indeed, some types of these vocalisations could reflect his state of comfort or discomfort. The results of this thesis open numerous grounds for thought in terms of neonatal care adaptations.
447

New determinants of olfactory habituation

Sinding, Charlotte, Valadier, François, Al-Hassani, Viviana, Feron, Gilles, Tromelin, Anne, Kontaris, Ioannis, Hummel, Thomas 27 July 2017 (has links)
Habituation is a filter that optimizes the processing of information by our brain in all sensory modalities. It results in an unconscious reduced responsiveness to continuous or repetitive stimulation. In olfaction, the main question is whether habituation works the same way for any odorant or whether we habituate differently to each odorant? In particular, whether chemical, physical or perceptual cues can limit or increase habituation. To test this, the odour intensity of 32 odorants differing in physicochemical characteristics was rated by 58 participants continuously during 120s. Each odorant was delivered at a constant concentration. Results showed odorants differed significantly in habituation, highlighting the multifactoriality of habituation. Additionally habituation was predicted from 15 physico-chemical and perceptual characteristics of the odorants. The analysis highlighted the importance of trigeminality which is highly correlated to intensity and pleasantness. The vapour pressure, the molecular weight, the Odor Activity Value (OAV) and the number of double bonds mostly contributed to the modulation of habituation. Moreover, length of the carbon chain, number of conformers and hydrophobicity contributed to a lesser extent to the modulation of habituation. These results highlight new principles involved in the fundamental process of habituation, notably trigeminality and the physicochemical characteristics associated.
448

Olfactory threshold and odor discrimination ability in children – evaluation of a modified “Sniffin’ Sticks” test

Gellrich, Janine, Stetzler, Carolin, Oleszkiewicz, Anna, Hummel, Thomas, Schriever, Valentin A. 14 November 2017 (has links)
The clinical diagnostics of olfactory dysfunction in children turns out to be challenging due to low attention span, insufficient linguistic development and lack of odor experiences. Several smell tests have been developed for adults. Most of these examinations take a relatively long time and require a high level of concentration. Therefore, the aim of the current study was to evaluate an odor discrimination and olfactory threshold test using the frequently used “Sniffin’ Sticks” in children and adolescents in a simplified two-alternative-forced-choice version (2AFC) and compare it to the original three-alternative-forced-choice test (3AFC). One-hundred-twenty-one healthy participants aged between 5 and 17 years took part in this study. Within each of the two sessions participants underwent olfactory testing using the modified 2AFC as well as the standard 3AFC method. A better test-retest reliability was achieved using the original 3AFC method compared to the modified 2AFC. This was true for the odor discrimination as well as the olfactory threshold. Age had a significant influence on both tests, which should be considered when testing young children. We discuss these findings with relation to the existing norms and recommend using the 3AFC version due to a better test-retest reliability to measure olfactory function in children.
449

Accurate Detection of Parkinson’s Disease in Tremor Syndromes Using Olfactory Testing

Wolz, Martin, Hähner, Antje, Meixner, Linda, Löhle, Matthias, Reichmann, Heinz, Hummel, Thomas, Storch, Alexander 19 May 2020 (has links)
Background/Aims: The diagnostic value of olfactory testing for the discrimination of tremor-dominant Parkinson’s disease (PD) from other tremor disorders remains enigmatic. We evaluated whether olfactory testing can accurately detect PD in tremor patients. Methods: A retrospective analysis of 299 consecutive subjects referred for the differential diagnosis of a tremor disorder was done. Olfactory testing was performed using ‘Sniffin’ Sticks’, resulting in a composite TDI score of odor threshold (T), discrimination (D), and identification (I). Receiver operating curve (ROC) plots were used to calculate sensitivity/specificity for the detection of PD. Results: Of all subjects, 167 (55.9%) had PD and 85 (28.4%) had essential tremor (ET). The mean TDI score in PD was significantly reduced compared to those in ET and other tremor disorders with no differences between ET and other tremor disorders. ROC analysis revealed strong correlations of TDI scores with PD [area under the curve: 0.85 (95% CI: 0.80–0.89); p < 0.001]. The highest Youden index was observed for a TDI score <25 (Youden index: 0.58). Using this cutoff score and that generated from normative data of healthy controls, the TDI score provided high sensitivity (negative predictive value) and specificity (positive predictive value) of approximately 80% for detecting PD. Conclusion: Olfactory testing is a useful, easily applied and inexpensive diagnostic test which is helpful to detect PD among tremor patients.
450

Uticaj ženskih polnih hormona na funkciju nosa u menstrualnom ciklusu i postmenopauzi / An impact of female sex hormones on the nasal function in menstrual cycle and postmenopause

Bogdan Maja 22 October 2020 (has links)
<p>Funkcija nosa povezana je sa različitim anatomskim, fiziolo&scaron;kim i emocionalnim faktorima. Postoji mnogo teorija koje su poku&scaron;ale da objasne efekat ženskih polnih hormona (estrogena i progesterona) na fiziologiju nosa, ali sam mehanizam njihovog dejstva jo&scaron; uvek ostaje izazov za mnoge istraživače. Prethodno je opisano da ženski polni hormoni mogu da izazovu nazalnu opstrukciju, povećavajući ekspresiju histaminskih H1 receptora i menjajući koncentraciju neurotransmitera, &scaron;to dovodi do edema nosne sluznice i modifikacije nazalnog otpora. Kada je reč o mirisnoj funkciji na malom broju ispitanika i u različito dizajniranim studijama je pokazano da je u fazi ovulacije mirisni prag značajno niži u odnosu na folikularnu i luteinsku fazu, međutim ne postoje podaci o identifikaciji i diskriminaciji mirisa u menstrualnom ciklusu. Nizak nivo estrogena prouzrokovan fiziolo&scaron;kom atrofijom jajnika u postmenopauzi može dovesti do hiposmije ili čak anosmije, &scaron;to predstavlja jo&scaron; jedan dokaz o osetljivosti nazalne sluznice na estrogen.&nbsp; Cilj ovog istraživanja je bio da se ispita uticaj ženskih polnih hormona na respiratornu i mirisnu funkciju nosa u menstrualnom ciklusu i postmenopauzi. Istraživanje je u celosti prospektivno, sprovedeno je na Zavodu za fiziologiju, Medicinskog fakulteta, Univerziteta u Novom Sadu. Uključeno je 204 osoba ženskog pola koje su bile podeljene u dve grupe. Prvu grupu su činile 103 devojke uzrasta 23,126 &plusmn; 4,597 godina u reproduktivnom periodu sa regularnim menstrualnim ciklusom i 101 žena prosečnog uzrasta 60,069 &plusmn; 5,570 u postmenopauzi. Respiratorna i mirisna funkcija nosa procenjene su uz pomoć odgovarajućih standaradizovanih objektivnih i subjektivnih metoda. Funkcija donjih disajnih puteva ispitana je uz pomoć spirometrije. Kod žena u reproduktivnom periodu testiranje se vr&scaron;ilo u fazi ovulacije i lutealnoj fazi menstrualnog ciklusa, a kod ispitanica u postmenopauzi jednom. Nakon određivanja prvog plodnog dana ispitanice su uz pomoć standardizovanih urin - tračica za određivanje pika luteinizirajućeg hormona u urinu utvrđivale momenat ovulacije, dok se drugo testiranje u lutealnoj fazi vr&scaron;ilo sedam dana nakon prvog. Respiratorna funkcija nosa je značajno lo&scaron;ija u fazi ovulacije u odnosu na progesteronsku fazu menstrualnog ciklusa,ali se značajno ne razlikuje između žena u reproduktivnom periodu i žena u postmenopauzi. Subjektivni osećaj nazalne opstrukcije značajno se ne razlikuje u različitim fazama menstrualnog ciklusa, kao ni između testiranih populacija zdravih žena. Sposobnost identifikacije mirisa je statistički značajno slabija, a subjektivni osećaj intenziteta mirisa izraženiji u fazi ovulacije u odnosu na luteinsku fazu menstrualnog ciklusa. Međutim, sposobnost identifikacije mirisa značajno je lo&scaron;ija kod žena u postmenopauzi u odnosu na obe faze menstrualnog ciklusa. Reaktivnost nosne sluznice značajno je veća u fazi ovulacije u odnosu na lutealnu fazu menstrualnog ciklusa, ali se ista ne razlikuje između žena u reproduktivnom period i žena u postmenopauzi. Respiratorna i mirisna funkcije nosa u testiranim populacijama zdravih žena nisu značajno povezane.</p> / <p>The nasal function is associated with various anatomical, physiological and emotional factors. There are many theories that have tried to explain the effect of female sex hormones (estrogen and progesterone) on the nasal physiology, but the mechanism still remains unknown for many researchers. It has been previously described that female sex hormones can cause nasal obstruction by increasing the expression of histamine H1 receptors and altering the concentration of neurotransmitters, which leads to edema of the nasal mucosa and modification of nasal resistance. When it comes to olfaction on a small number of subjects and in differently designed studies, it was shown that in the ovulatory phase the olfactory threshold is significantly lower compared to the follicular and luteal phase, however there are no data on the identification and discrimination of odors in the menstrual cycle. Low estrogen levels caused by physiological atrophy of the ovaries in postmenopause can lead to hyposmia or even anosmia, which is another proof of the sensitivity of the nasal mucosa to estrogen.&nbsp; The aim of this study was to examine the effect of female sex hormones on respiratory and olfactory function of the nose in the menstrual cycle and postmenopause. The research is prospective and it was conducted at the Department of Physiology, Faculty of Medicine, University of Novi Sad. It included 204 females who were divided into two groups. The first group consisted of 103 women aged 23.126 &plusmn; 4.597 years in the reproductive period with a regular menstrual cycle and 101 women with an average age of 60.069 &plusmn; 5.570 in the postmenopausal period. The respiratory and olfactory function of the nose were assessed using appropriate standardized objective and subjective methods. The lower airway function was examined using spirometry. Young women in reproductive period were tested twice, in the ovulatory and luteal phase of the menstrual cycle, and the postmenopausal women were tested only once. After menstrual bleeding the participans used standardized urine strips consecutively day by day to determine ovulation (the peak of the luteinizing hormone (LH) in plasma which pointed out the estrogen plasma peak). The test was positive if two horizontal pink streaks appeared on the strip 5 to 10 minutes after the contact with the urine. One pink streak indicates a correctly performed test, while the second streak appears only if there is an LH peak. Within 24 hours of confirmed LH peak, the subjects were tested for the first time. The second measurement was performed in the luteal phase of the menstrual cycle (the progesterone plasma peak) seven days after the first one.&nbsp; The nasal respiratory function is significantly worse in the ovulatory phase compared to the luteal phase of the menstrual cycle, but it does not differ significantly between women in the reproductive period and postmenopausal women. The subjective sense of the nasal obstruction does not differ significantly in different phases of the menstrual cycle, as well as between tested populations of healthy women. The odor identification ability is statistically significant weaker and the subjective sense of odor intensity is more pronounced in the ovulatory phase compared to the luteal phase of the menstrual cycle. However, the ability to identify odors is significantly worse in postmenopausal women compared to both phases of the menstrual cycle. The reactivity of the nasal mucosa is significantly higher in the ovulatory phase compared to the luteal phase of the menstrual cycle, but it does not differ between women in the reproductive period and postmenopausal women. The respiratory and olfactory nasal functions in these tested populations are not significantly corelated.</p>

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