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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.
371

Peripheral human colour vision : from cone contrast to colour perception

Panorgias, Athanasios January 2011 (has links)
It is well known that the colour preferences of ganglion and LGN cells do not match the four perceptually simple colours red, green blue and yellow. It is also known that although colour perception is distorted in the peripheral visual field, there are four hues that appear stable with eccentricity. These are defined as peripherally invariant hues. Both of these observations must in some way reflect the physiological substrate of neurons at different stages of the primary visual pathway. The experiments described here are aimed at understanding the link between the physiology and the perception of colour by studying the characteristics of peripheral colour visionThe following questions have been addressed; i) to what extent does colour matching rely on the retinal physiological substrate? ii) what is the reason for the discrepancy between invariant and unique green and how is cone contrast linked to this paradox? iii) how are the `special' hues (invariant and unique) related to human evolution? iv) how does peripheral colour vision vary between males and females?An asymmetric colour matching paradigm and a colour naming task have been employed. In the colour matching task, 24 chromatic axes of variable purity are used. Observers match the chromaticity of a 3 degree peripheral spot with that of a 1 degree parafoveal spot. The results are expressed in terms of hue rotation, saturation match and cone contrast. In the colour naming experiment the observers name 40 chromatic axes as either red, blue, green or yellow and colour naming functions are derived. The central maxima of these functions are defined as the unique hues. The results suggest that colour matching and cone opponency reflect the characteristics of the retinal neural network as they exhibit nasal-temporal asymmetries, similar to known physiological asymmetries. Although three of the peripherally invariant hues match the unique counterparts, invariant and unique green are markedly different for all observers. In an important control experiment unique hues are shown to be stable with eccentricity and purity. This confirms that these attributes are not confounding factors for the observed discrepancy between invariant and unique green. Unlike for the other 'special' hues the RMS cone contrast of invariant green differs markedly between parafoveal and peripheral targets. It is likely that the cone contrast remains unchanged only if the stimuli excite the same number of cones. Two invariant and two unique hues (blue and yellow) fall on the daylight locus suggesting that discrimination in these regions of the colour space is strongly influenced by terrestrial illumination. Moreover, the inter-individual variability is found to be minimised around the daylight locus showing that the blue-yellow system is more stable across colour normal populations than the red-green system. A statistically significant difference is demonstrated between the peripheral colour vision of males and females. This may be attributed to the M-cone polymorphism which in addition to X-chromosome inactivation, results in more than three cone types in the female retina.
372

Aquisição das vogais nasais francesas [ɛ̃], [ã] e [ɔ̃] por aprendizes brasileiros: aspectos acústico-articulatórios / Acquisition of French nasal vowels [ɛ̃], [ã] and [ɔ̃] by Brazilian learners: acoustic-articulatory aspects

Correa, Bruna Teixeira 23 February 2017 (has links)
Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2017-06-21T20:27:05Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Bruna_Teixeira_Correa.pdf: 9689804 bytes, checksum: fe5f90a03f7fea35e63a7d704bd3c1be (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-06-21T21:13:49Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Bruna_Teixeira_Correa.pdf: 9689804 bytes, checksum: fe5f90a03f7fea35e63a7d704bd3c1be (MD5) / Made available in DSpace on 2017-06-21T21:13:56Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Bruna_Teixeira_Correa.pdf: 9689804 bytes, checksum: fe5f90a03f7fea35e63a7d704bd3c1be (MD5) Previous issue date: 2017-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Este trabalho se propõe a investigar a aquisição das vogais nasais [ɛ̃], [ã] e [ɔ̃] da Língua Francesa por aprendizes do curso de licenciatura em Letras Português/Francês da Universidade Federal de Pelotas. Em termos articulatórios, essa classe de segmentos caracteriza-se pelo abaixamento do véu palatino, o que gera o acoplamento dos tubos nasal e oral (SEARA, 2000; DEMOLIN e MEDEIROS, 2006; BARBOSA e MADUREIRA, 2015) e, consequentemente, por aspectos acústicos diferentes daqueles encontrados nas vogais orais. Com a passagem livre do ar no trato nasal, o primeiro formante (F1) tende a abaixar e o terceiro (F3) a aumentar (HAWKINS e STEVENS, 1985; DELVAUX, 2001). Há também uma modificação na amplitude de picos espectrais – menor para as nasais –, aparecimento de picos espectrais adicionais e uma maior duração para os referidos segmentos (MORAES e WETZELS, 1992; SOUSA, 1994). Para desenvolver essa pesquisa, tomou-se como base a Fonologia Gestual (BROWMAN e GOLDSTEIN, 1986), cujas análises abordam o caráter dinâmico da fala e tratam o gesto como primitivo de análise. Para tanto, foram realizadas coletas de dados orais e articulatórios com três grupos de informantes: Grupo I - 8 aprendizes de FLE de semestres distintos (2º, 3º, 5º, 7º e 8º) do curso de licenciatura; Grupo II - 4 nativas de francês; e Grupo III - 4 nativas de português brasileiro. Os instrumentos de coletas consistem para a produção oral, em um teste de eliciação de palavras e de logatomas em frase-veículo e para a produção articulatória, somente o segundo tipo de teste já referido. As coletas dos Grupos I e III foram realizadas na cabine acústica do Laboratório Emergência da Linguagem Oral (LELO/UFPel); já as do Grupo II, em Paris/França. Para análise acústica dos dados de produção oral, foi utilizado o software PRAAT versão 6.0.20; para a análise articulatória, o software Articulate Assistant Advanced (AAA), versão 2.16.11. A análise dos segmentos dos dois grupos de nativas constatou que (i) as vogais nasais do PB têm maior duração absoluta, bem como maior duração de seus murmúrios; (ii) a duração relativa da fase nasal das vogais do francês são mais longas; (iii) para diferenciar segmento nasal de oral, a nativa do francês posterioriza seus movimentos de língua, já a do português, eleva. Quanto aos dados das aprendizes, foi possível constatar: (i) as vogais nasais do francês têm maior duração relativa e absoluta quando comparadasàs do português; (ii) maior duração absoluta da fase nasal das vogais da LE; (iii) menores valores de duração do murmúrio no FR; (iv) generalização de gestos de língua da informante do 2º semestre para as três vogais nasais do FR e (v) distinção acurada da informante do 8º. / This work aims to investigate the acquisition of the nasal vowels [ɛ̃], [ã] and [ɔ̃] of French by learners in an undergraduate course in Languages (Portuguese and French) of Federal University of Pelotas (UFPel, Brazil). In articulatory terms, this class of segments is characterized by a lowering of the velum, which makes a connection between nasal and oral tubes (SEARA, 2000; DEMOLIN and MEDEIROS, 2006; BARBOSA and MADUREIRA, 2015). Consequently, the acoustic aspects that characterize these vowels are different from those found in oral vowels. With the free passage of air in the nasal tract, the first formant value (F1) tends to lower and the third formant value (F3) tends to rise (HAWKINS and STEVENS, 1985; DELVAUX, 2001). There is also a change in the width of spectral peaks – which is smaller for nasal vowels –, as well as the appearance of additional spectral peaks and a longer length for these segments (MORAES and WETZELS, 1992; SOUSA, 1994). In order to develop this research, Gestural Phonology (BROWMAN and GOLDSTEIN, 1986) has been adopted as a theoretical basis. Its analyses approach the dynamic nature of speech and regard the gesture as a primitive of analysis. To this end, collections of oral and articulatory data have been made with three groups of informants: Group I – 8 learners of French as a foreign language (FFL) in different semesters (2nd, 3rd, 5th, 7th and 8th) of the course; Group II – 4 native speakers of French; and Group III – 4 native speakers of Brazilian Portuguese (BP). The data collection instruments for oral production were tests of elicitation of words and pseudowords in a carrier phrase and, for articulatory production, only the second type of test has been applied. The data collections with Groups I and III were made in an acoustic cabin of the Emergence of Oral Language Laboratory (LELO/UFPel); the data collections of Group II were made in Paris, France. The softwares used for the analyses were Praat (version 6.0.20) for oral production data, and Articulate Assistant Advanced (AAA, version 2.16.11) for articulatory data. The analysis of the segments produced by both groups of native speakers showed that (i) BP nasal vowels have longer absolute length, as well as a longer length of their murmurs; (ii) the relative length of the nasal phase of French vowels is longer; (iii) in order to distinguish nasal segments from oral ones, the native speaker of French posteriorizes her tongue movements, whereas the speaker of Portuguese elevates them. Regarding the data produced by learners, it was possible to verify: (i) longer relative and absolute lengths in French nasal vowels when compared to Portuguese; (ii) longer absolute length of the nasal phase in vowels of the foreign language; (iii) lower values of murmur length in French; (iv) generalization of tongue gestures by the 2nd semester informant for the three French nasal vowels and (v) accurate distinction by the 8th semester informant.
373

Traumatismos bucomaxilofaciais em um hospital público do Brasil Central: estudo retrospectivo / Maxillofacial trauma in a public hospital in Central Brazil: a retrospective study

Scartezini, Guilherme Romano 10 December 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-09-08T21:27:40Z No. of bitstreams: 2 Scartezini, Guilherme Romano - 2013.pdf: 1148660 bytes, checksum: 90b275997068b644fac95cddab8e6264 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-08T21:27:40Z (GMT). No. of bitstreams: 2 Scartezini, Guilherme Romano - 2013.pdf: 1148660 bytes, checksum: 90b275997068b644fac95cddab8e6264 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-12-10 / Aim: To evaluate epidemiological aspects of maxillofacial-oral injuries in hospitalized patients. Material and Methods: The sample was composed by 405 patients treated at the Department of Oral and Maxillofacial Surgery of the Emergency Hospital of Aparecida de Goiânia, Brazil, between 2011 and 2013. The following informations were collected from the patients’ medical records: gender, age, cause of injury, seasonal distribution, patient’s location and type of injury. The statistical treatment analyzed data from frequency distribution and chi-squared test. The level of significance was set at 5% for all analyses. Results: Higher occurrence of maxillofacial-oral injuries was observed in males (n=294; 72.59%), with 21-30 years old (n=106; 26.17%) and from the city of Aparecida de Goiânia. The main etiologic factors involved were vehicle traffic accidents (n=124; 30.62%), falls (n=92; 22.72%) and violence (n=87; 21.48%). The seasonal distribution showed that most cases occurred in autumn (n=154; 38.02%), followed by summer (n=138; 34.07%). The most common injuries were facial fractures (n = 324; 80.0%), the nasal bone, the most affected (n = 161; 39.75%) anatomical region. Statistically significant associations between etiological factor, gender and age (p <0.005) were observed. Conclusions: There were a high number of maxillofacial-oral injuries in males, aged less than 30 years old and due vehicle traffic accidents. / Objetivo: avaliar os aspectos epidemiológicos dos traumatismos bucomaxilofaciais em prontuários de pacientes atendidos em um hospital público do Brasil Central. Material e método: a amostra do estudo foi proveniente da revisão de prontuários de 405 pacientes atendidos no serviço de cirurgia e traumatologia bucomaxilofacial (CTBMF) do Hospital de Urgências de Aparecida de Goiânia (HUAPA) - GO, Brasil, entre os anos de 2011 e 2013. Os seguintes dados foram coletados dos registros hospitalares de cada paciente: gênero, idade, fator etiológico, data do atendimento, procedência e região anatômica atingida. O tratamento estatístico analisou os dados frente à distribuição de frequência e qui-quadrado. O nível de significância foi de p<0,05. Resultados: observou-se elevada frequência de traumatismos bucomaxilofaciais em indivíduos do gênero masculino (n=294; 72,59%). A faixa etária mais acometida foi entre 21-30 anos (n=106; 26,17%), provenientes da cidade de Aparecida de Goiânia. Os principais fatores etiológicos foram os acidentes de trânsito motorizados (n=124; 30,62%), quedas (n=92; 22,72%) e violência (n=87; 21,48%). A distribuição sazonal evidenciou elevado número de traumatismos no outono (n=154; 38,02%) e no verão (n=138; 34,07%). O traumatismo mais comum foi a fratura facial (n=324; 80,0%), sendo o nariz, a região anatômica mais atingida (n=161; 39,75%). Foram observadas associações significantes entre fator etiológico, gênero e faixa etária (p<0,005). Conclusão: os dados obtidos se assemelham aos encontrados na literatura, no que diz respeito à prevalência do gênero masculino, da faixa etária e dos acidentes de trânsito como principal agente etiológico.
374

O papel da turbinectomia inferiorparcial endoscópica narinosseptoplastia : um ensaio clínico randomizado com avaliação de qualidade de vida

Moura, Bianca Hocevar de January 2017 (has links)
Objetivos: Avaliar o papel da turbinectomia inferior parcial endoscópica (TIPE) na rinosseptoplastia primária sobre os desfechos de qualidade de vida, complicações e tempo cirúrgico. Delineamento: Ensaio clínico pragmático, randomizado, duplo-cego em um centro único e de grupos paralelos. Métodos: Indivíduos maiores de 16 anos, com queixas estéticas e obstrução nasal, candidatos à rinosseptoplastia primária, avaliados entre março de 2014 e maio de 2015, em um Hospital Terciário Universitário no Brasil. Pacientes elegíveis foram randomizados para receberem ou não TIPE concomitantemente à cirurgia. Desfechos: Diferença absoluta dos escores pré e pós-operatórios em qualidade de vida específica, pela aplicação dos questionários Nasal Obstruction Symptom Evaluation Portuguese (NOSE-p) e Rhinoplasty Outcome Evaluation (ROE), e geral, através de aplicação do World Health Organization Quality of Life (WHOQOL)-breve. Os desfechos eram cegados e acessados somente três meses após a cirurgia. O protocolo foi registrado no ClinicalTrials.gov (NCT02231216). Resultados: 50 pacientes foram incluídos, maioria caucasiana com rinite alérgica com sintomas moderados a severos. A média de idade foi 36 (±14,5) anos. Os escores de qualidade de vida específicos e gerais melhoraram independentemente da intervenção TIPE (p < 0,001). ANCOVA foi aplicada para controlar potenciais fatores confundidores. Não houve divergência entre a diferença absoluta nos pacientes submetidos ou não a TIPE nos escores NOSE-p (-50,5 vs. -47,6; p=0,723); ROE (47 vs. 44,8; p= 0,742) e todos os domínios do WHOQOL-breve (p > 0,05). Não houve diferença entre os grupos sobre a presença de complicações. O tempo cirúrgico foi maior no grupo TIPE (212 minutos ± 7,8 vs. 159,1 ± 5,6; p ˂ 0,001). Conclusão: A redução das conchas inferiores através da TIPE durante a rinosseptoplastia primária não melhorou, em curto prazo, a qualidade de vida geral nem específica. O uso de TIPE aumenta o tempo cirúrgico consideravelmente, sem adicionar benefício aos escores avaliados. Não houve diferença na incidência de complicações no pós-operatório, sugerindo a segurança da técnica. / Objectives/Hypothesis: To evaluate the impact of endoscopic partial inferior turbinectomy (EPIT) associated with primary Rhinoseptoplasty on quality of life outcomes (QOL), complications, and surgical duration. Study Design: Randomized clinical trial. Methods: Individuals with nasal obstruction aged ≥ 16 years who were candidates for functional and aesthetics primary Rhinoseptoplasty were evaluated from March 2014 through May 2015 at a tertiary university hospital in Brazil. Eligible participants were randomly allocated to rhinoseptoplasty with or without EPIT. Outcomes: Absolute change (postoperative –preoperative) in the following QOL scores: Nasal Obstruction Symptom Evaluation-Portuguese (NOSE-p), Rhinoplasty Outcome Evaluation (ROE) and World Health Organization Quality of Life (WHOQOL)-bref (to measure general QOL). Outcomes were blindly assessed 3 months postoperatively. The protocol was registered at ClinicalTrials.gov (NCT02231216). Results: Fifty patients were studied. Most were Caucasian and had moderate/severe allergic rhinitis symptoms. Mean age was 36 (±14.5) years. Rhinoseptoplasty was associated with improvement in all QOL scores irrespective of turbinate intervention (P <0.001). ANCOVA was conducted to control for potential confounders. There was no difference between the groups in absolute score changes for NOSE-p (-50.5 vs. -47.6; P=0.723); ROE (47 vs. 44.8; P = 0,742), and all WHOQOL-bref score domains (P >0.05). There were no differences between the groups regarding presence of the complications. Surgical duration was higher in the EPIT group (212 minutes ± 7.8 vs. 159.1 ± 5.6; p ˂ 0.001). Conclusions: Turbinate reduction through EPIT during primary rhinoseptoplasty did not improve short-term general and specific QOL outcomes. The use of EPIT increases surgical time considerably without improving QOL scores. There was no difference in postoperative incidence of complications, suggesting that EPIT is a safe technique.
375

The effect of topical antifibrinolytics and a novel chitosan gel on haemostasis and wound healing in endoscopic sinus surgery.

Athanasiadis, Theodore January 2009 (has links)
Introduction: Endoscopic sinus surgery (ESS) is at present the gold standard therapeutic modality for chronic rhinosinusitis (CRS) resistant to medical therapy. Whilst results from ESS for CRS are generally good, postoperative bleeding and impaired wound healing with adhesion formation remains a concern. Due to patient discomfort and the detrimental effects on wound healing caused by most packing materials, many surgeons no longer routinely use nasal packing. Surgeons have in the past sought agents which would provide post-operative haemostasis without detrimentally affecting wound healing. Antifibrinolytics have been available for many years, however, their topical application has only been explored in the last few years. Recently different forms of chitosan have separately shown significant promise as powerful haemostatic and anti-adhesion agents. The aim of this thesis was to explore the progressive understanding of the interaction between haemostasis and wound healing with possible development of a novel agent. Methods: The first step to scientifically assess bleeding after sinus surgery was to develop a standardised method of video endoscopy and grading the surgical field during ESS. This was done as a multinational collaborative trial. Once this assessment tool was validated a randomised controlled trial evaluating the effect of two antifibrinolytics (epsilon aminocaproic acid and tranexamic acid) was conducted. Further evaluation was then conducted on other possible hemostatic and antiadhesion substances. This included various combinations of a novel chitosan gel. These gels were trialled in vitro to determine their effect on human nasal fibroblasts derived from CRS patients. Fibroblast adhesion and proliferation as well as closure of standardised wounds were studied. The most promising of these gels was then used in an in vivo sheep model. Once effectiveness of the chitosan-dextran gel was shown in the laboratory, this was evaluated against a number of currently available hemostatic and anti-adhesion substances in a standardised model of wound healing in sheep with CRS. This model had been previously extensively validated in our department. Full thickness mucosal injuries were created on the lateral nasal wall and ethmoids of twenty sheep and recombinant tissue factor (rTF), SprayGel or Chitosan-Dextran derivative gel applied topically in a randomized fashion. Adhesion formation and severity as well as microscopic wound healing and ciliary function were analysed at day 28, 56, 84 and 112 post initial surgery. A further sheep study was conducted applying chitosan dextran gel to standardised mucosal injuries and comparing its effect on the control of bleeding to control. Bleeding time and grade were recorded and wound healing monitored via serial videoendoscopy over two weeks and objectively measured. Results: a) Assessment of the bleeding scales showed that inter and intra observer reliability for both scales tested were significantly improved by employing a standardized video-endoscopy technique. The Wormald scale proved to be more reliable and sensitive to changes in the most common surgical fields encountered in ESS. b) Tranexamic acid showed a modest but clinically significant improvement in the surgical field at 2, 4 and 6 minutes after application. Epsilon aminocaproic acid did not effectively improve the surgical field. c) Nasal fibroblast adhesion and proliferation were significantly impaired with dextran and chitosan. The most effective ratio that delayed but did not prevent wound closure were 5 % chitosan: 5 % dextran gel. d) In a standardised sheep model of mucosal wound healing the chitosan gel significantly decreased lateral nasal wall and ethmoidal adhesions at all time points. The chitosan group had a significantly greater percentage of re-epithelialisation and reciliation than control and rTF. In addition the mean cilial grade in the chitosan group was significantly better than control. e) The chitosan dextran gel was significantly more haemostatic at 2,4, and 6 minutes after injury with no significant difference noted in wound healing. Conclusions: Standardised methods of videoendoscopy and grading the surgical field in ESS are valuable tools for further research. Tranexamic acid significantly improved the surgical field to a moderate degree in ESS compared to control. Chitosan gel is a promising new powerful haemostatic bio-polymer which has a mild inhibitory effect on fibroblast attachment and proliferation. This may partially explain the significant improvement in microscopic wound healing and reduction in adhesion formation seen in a sheep model of chronic sinusitis. Future work evaluating this gel in the setting of a human trial is currently underway. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1375402 / Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 2009
376

Intérêt des tests microbiologiques dans le diagnostic de laspergillose naso-sinusale dans lespèce canine et évaluation dun nouveau protocole thérapeutique topique

Billen, Frédéric 20 October 2008 (has links)
Laspergillose naso-sinusale (ANS) est une des causes les plus fréquentes de jetage nasal chez le chien. Cette affection peut être fortement suspectée sur la base du signalement, de lanamnèse et de lexamen clinique. Cependant, la confirmation du diagnostic requiert la combinaison de divers examens complémentaires dont lendoscopie et limagerie médicale en coupe, deux techniques principalement réservés aux centres de médecine vétérinaire spécialisés. Il serait pourtant utile pour le vétérinaire praticien de pouvoir poser lui-même le diagnostic grâce à une méthode alternative fiable et peu/non-invasive. Cest pourquoi, nous avons, dans la première partie de ce travail, investigué plus en profondeur lutilité de deux types de prélèvements faciles à prélever pour le vétérinaire (du sang et des sécrétions nasales) dans le diagnostic de lANS. Lors dune première étude, nous avons investigué lintérêt de la détection danticorps spécifiques dAspergillus dans le sérum par deux tests sérologiques (un test dimmunodiffusion sur gel dagarose (AGDD) et un test ELISA IgG indirect) en utilisant une nouvelle solution commercialisée dantigènes purifiés dAspergillus. Nous avons également investigué la valeur diagnostique de la détection de galactomannan (antigènes dAspergillus) (GM) dans le sérum au moyen dun test ELISA (PlateliaTM Aspergillus). Alors que les tests sérologiques (AGDD et ELISA IgG) ont montré une excellente spécificité (100% et 96.8% respectivement) et une bonne sensibilité (76.5% et 88.2% respectivement), une spécificité correcte (82,3%) et une très faible sensibilité (23,5%) ont été obtenues pour la détection sérique de GM. Lexplication la plus logique à cette faible sensibilité réside probablement dans le caractère non-invasif de lANS dans lespèce canine. Dans une deuxième étude, nous avons tenté de déterminer le type de prélèvement nasal et la température dincubation les plus appropriés pour lobtention de résultats fiables lors de cultures fongiques de sécrétions nasales chez le chien. Trois types déchantillon nasal dinvasivité croissante (sécrétions nasales par écouvillon, biopsie de muqueuse nasale et placard fongique) et deux températures dincubation (air ambiant et 37°C) ont été comparés. Nos résultats ont montré que les placards fongiques étaient les échantillons de choix pour les cultures fongiques et quune incubation à 37°C améliorait également significativement la sensibilité de la culture fongique par rapport à la température ambiante (avec une sensibilité de 88% et une spécificité de 100%). Dans une troisième étude, nous avons investigué la valeur diagnostique des cultures fongiques à 37°C et de la détection de GM à partir de deux nouveaux types de prélèvement non-invasifs des sécrétions nasales (un nouvel écouvillon en nylon plus performant (le flocked swab (FSwab)) et du liquide de lavage nasal (LLN)) en comparaison avec les écouvillons traditionnels en coton (EC) et les placards fongiques. Malgré un nombre croissant de résultats de cultures positif avec lutilisation respective dEC, de FSwab et de LLN à partir des échantillons prélevés chez les chiens avec ANS, il ny avait pas de différence significative entre les types déchantillon. Même sil y avait significativement plus de GM au sein des LLN et des FSwab quau sein des EC si on tenait compte de lensemble des chiens (quil soient atteints dANS, de maladie non-fongiques ou indemnes de maladie respiratoire), lutilisation des ces deux nouvelles méthodes déchantillonnage na pas entrainé daugmentation significative des GM dans les sécrétions nasales des chiens atteints dANS par rapport à la quantité obtenue en utilisant les EC. Globalement, tous prélèvements confondus, ce test sest révélé peu sensible (41.7%) et modérément spécifique (77.4%) pour le diagnostic dANS et il ny a pas eu de différence de sensibilité en comparaison avec les cultures fongiques. Si le diagnostic de lANS représente un challenge pour le clinicien, son traitement lest tout autant. Aucune méthode thérapeutique nest à lheure actuelle totalement satisfaisante. En effet, soit la méthode nécessite un abord invasif des cavités nasales et/ou sinus frontaux, soit elle nécessite une anesthésie de longue durée. De plus, aucune des méthodes décrites nest efficace dans tous les cas. Le traitement idéal devrait donc être efficace, non-invasif et de courte durée. Cest pourquoi, dans une quatrième étude, nous avons testé lefficacité dun nouveau traitement topique rapide et non-invasif (dépôt sous endoscopie dune crème à base de bifonazole 1% (Canestene, Bayer)) comme traitement unique (DC) ou en combinaison avec un traitement classique dirrigation à lénilconazole 2% (DEC) chez des chiens atteints dANS. Il en a résulté que lajout du dépôt de bifonazole au protocole classique (DEC) offre une guérison dans 100% des cas après un voire deux traitements ; ces résultats sont comparables voire meilleurs que les résultats des autres études relatives au traitement topique de lANS chez le chien. Les résultats de cette étude ont montré également que le protocole DC nest efficace que lors dinfection fongique modérée et quil peut dès lors remplacer le protocole DEC lorsquil ne reste quun nombre réduit de placards fongiques après un traitement classique. Par ailleurs, la durée du protocole DC est nettement moins longue que celle du protocole DEC permettant de diminuer le temps danesthésie et donc le coût du traitement. Par contre lutilisation unique du protocole DC sur les cas dANS sévère semble peu efficace.
377

Eosinophil Inflammation in Allergic Disease : Clinical and experimental studies in allergic asthma and allergic rhinitis

Kämpe, Mary January 2010 (has links)
Allergic diseases are chronic inflammatory conditions, characterised by eosinophil inflammation systemically and in target organs, where cytotoxic granule proteins are responsible for tissue injury. Allergic rhinitis is known to be a risk factor for the development of asthma, yet not all with rhinitis develop asthma. The overall aim was to investigate the involvement of eosinophils in allergic rhinitis and allergic asthma in vivo and in experimental settings, with a focus on differences between rhinitis and asthma. Birch pollen allergy was used as a model and patients were studied during pollen season and after nasal and bronchial allergen challenge. During pollen season and at baseline, allergic rhinitis and allergic asthma had the same degree of systemic eosinophil inflammation. Despite this, impairment in lung function during season and increased bronchial responsiveness at baseline were more common in the asthmatics. Systemic inflammation was more pronounced after seasonal exposure than after experimental challenge. Allergic rhinitis and allergic asthma had the same degree of eosinophil airway inflammation after bronchial challenge, but only the asthmatics had increased bronchial responsiveness measured as PD20 for birch allergen. Allergen primed eosinophils were investigated in vitro for C3b-induced degranulation after seasonal and experimental challenge. The released amount of eosinophil granule proteins was within the same range for all three allergen challenge models with just minor differences in propensity for degranulation between rhinitics and asthmatics. Signalling through PI3K for degranulation was studied with the specific inhibitor Wortmannin. PI3K signalling for eosinophil degranulation was clearly involved in allergic rhinitis and allergic asthma irrespective of the model for allergen exposure. Asthmatics demonstrated less inhibition of degranulation through PI3K during pollen season, indicating that other pathways contribute to eosinophil degranulation in allergic asthmatics. Conclusion: Allergic rhinitis and allergic asthma present with the same degree of systemic and local eosinophil inflammation. The eosinophils are primed for degranulation equally and follow the same pathway through PI3K for degranulation. Our data indicates that eosinophil inflammation per se is not sufficient for the development of asthma.
378

Endogenous and Exogenous Regulation of Exhaled Ions in Patients with Cystic Fibrosis

Wheatley, Courtney M. January 2013 (has links)
Exercise has become a vital component of the therapy regimen prescribed to cystic fibrosis (CF) patients due to its systemic benefits, such as increased sputum expectoration, attenuation of the expected 2-3% annual decline in pulmonary function, and extended life expectancy. However, exercise still is not viewed as being as beneficial as pharmacological treatments by many CF patients and can be intimidating. My aims in this study were two-fold; first, to determine the ideal exercise intensity for individuals with CF; and second, to determine if exercise at this ideal intensity could provide improvements in ion regulation in the lungs, which was measured using exhaled breath condensate (EBC) collection and nasal potential difference (NPD), that were comparable to one of their standard pharmacological therapies, albuterol. I hypothesized that with moderate intensity exercise, Na⁺ absorption would decrease from baseline due to Na⁺ channel inhibition, rather than increase or remain unchanged, as was expected with albuterol, and cause an even greater increase Cl- secretion compared to albuterol due to activation of both CF-dependent and independent Cl- efflux with exercise. CF (n=14) and healthy (n=16) subjects completed three visits, a baseline screening and two treatment visits. I collected EBC at baseline, 30- and 60-minutes post-albuterol administration on one visit, and at baseline and during three separate 15 min exercise bouts at low, moderate and high intensity on the other visit. Following the EBC collection, NPD was performed at 30- and 80-minutes post albuterol or following moderate and high intensity exercise. We also measured spirometry and diffusing capacity of the lungs for nitric oxide (DLNO) during each visit at the various time points. In CF subjects, moderate intensity exercise resulted in greater improvements in DLNO (39 ± 29vs.15 ± 22% change from baseline, exercise vs. albuterol respectively), similar levels of bronchodilation compared to 60-minutes post-albuterol administration, no change in Na⁺ absorption, and a four-fold increase in Cl- secretion. Our results suggest that moderate intensity exercise is the best dose for CF patients, and can provide comparable changes as its pharmacological counterpart albuterol, when compared over a short term duration.
379

Évaluation de l'utilisation des agents prévenant la résorption osseuse en situation réelle et impact de la non-adhésion au traitement sur la survenue de fractures ostéoporotiques : l'utilisation et les coûts directs des soins de santé

Blouin, Julie January 2008 (has links)
Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur.
380

Excrétion nasale et réponse sérologique à Mycoplasma bovis chez les génisses de remplacement de 0 à 7 mois d'âge dans 4 troupeaux laitiers au Québec: Étude de cohortes

Gasmi, Salima 10 1900 (has links)
En Amérique du Nord, Mycoplasma bovis est le plus pathogène des mycoplasmes retrouvés chez les bovins. Les principales maladies qu’on lui associe (maladies respiratoires, mammites, arthrites septiques et otites moyennes et/ou internes) constituent un défi à l’industrie laitière à cause de la difficulté à les traiter et à les prévenir par une vaccination. L’objectif principal de ce projet était d’étudier l’excrétion nasale et la réponse sérologique à M. bovis chez les génisses de remplacement, entre la naissance et 7 mois d’âge, dans 4 troupeaux laitiers au Québec. Quatre-vingt-trois paires mère/génisse provenant de 4 cohortes de bovins laitiers étaient prélevées mensuellement (génisses : 0 à 7 mois ; mères : 0, 1 et 5 mois après vêlage). Écouvillons nasaux et échantillons de lait étaient analysés par culture bactériologique et par immunofluorescence indirecte. Les anticorps circulants étaient détectés par le test ELISA. À la naissance, la prévalence sérologique des génisses était supérieure à celle des mères (P = 0,01). La transmission de M. bovis aux génisses par le lait et par l’excrétion nasale des mères était faible. L’âge moyen (jour) d’une génisse à sa 1ère excrétion nasale et sa 1ère séroconversion à M. bovis était loin de la période néonatale: 77,5 ± 11,2 (n = 22) et 96,8 ± 7,4 (n = 36) respectivement. Conclusion, les vaches adultes n’ont constitué qu’une voie mineure de transmission de M. bovis aux génisses, la principale voie de transmission était fort probablement le contact direct ou indirect avec d’autres génisses excrétrices nasales de M. bovis. / In North America, Mycoplasma bovis is the most pathogenic mycoplasma found in cattle. The main diseases associated with it (respiratory disease, mastitis, septic arthritis and otitis median and/or internal) are a challenge to the dairy industry because of the difficulty to treat them and to prevent them by vaccination. The principal objective of this project was to study nasal shedding and serological response to M. bovis in replacement heifers, between birth and 7 months of age, in four dairy herds in Quebec. Eighty three pairs cow/heifer in 4 cohorts of dairy cattle were sampled monthly (heifers: 0 to 7 months; cows: 0, 1 and 5 months after calving). Nasal swabs and milk samples were analyzed by bacteriological culture and by indirect immunofluorescence. Circulating antibodies were detected by ELISA test. At birth, the serologic prevalence of heifers was significantly higher than the serologic prevalence of cows (P = 0,01). Transmission of M. bovis to heifers in milk and nasal shedding from cows was low. The average age (days) of a heifer for first nasal shedding and first seroconversion to M. bovis was far from the neonatal period: 77,5 ± 11,2 days (n = 22) and 96,8 ± 7,4 days (n = 36) respectively. Conclusion, cows were only a minor route of transmission of M. bovis to heifers, the main route of transmission was most likely the direct or indirect contact with other heifers shedding M. bovis in their upper respiratory tract.

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