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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.
181

Cardiovascular complications of childhood obstructive sleep apnea syndrome.

January 2007 (has links)
Au, Chun Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves xxvii-lv). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT / In English --- p.ii / In Chinese --- p.v / LIST OF TABLES --- p.vii / ABBREVIATIONS / For Units --- p.ix / For Prefixes of the international system of units --- p.ix / For Terms commonly used in the report --- p.x / STATEMENT OF WORK DONE --- p.xvi / Chapter CHAPTER 1 --- Overview of Childhood Obstructive Sleep Apnea Syndrome (OSAS) / Chapter 1.1. --- Clinical Features of Childhood OSAS --- p.1 / Chapter 1.2. --- Definition of Childhood OSAS --- p.2 / Chapter 1.3. --- Prevalence of Childhood OSAS --- p.3 / Chapter 1.4. --- Pathophysiology --- p.4 / Chapter 1.5. --- Risk Factors --- p.6 / Chapter 1.6. --- Diagnosis --- p.10 / Chapter 1.7. --- Treatment / Chapter 1.7.1. --- Tonsillectomy and Adenoidectomy (T&A) --- p.12 / Chapter 1.7.2. --- Continuous Positive Airway Pressure (CPAP) --- p.14 / Chapter 1.7.3. --- Corticosteroids --- p.15 / Chapter 1.7.4. --- Leukotriene Receptor Antagonist --- p.16 / Chapter 1.8. --- Complications of Childhood OSAS / Chapter 1.8.1. --- Growth Failure --- p.17 / Chapter 1.8.2. --- Neurocognitive Abnormalities --- p.19 / Chapter 1.8.3. --- Cardiovascular Abnormalities --- p.20 / Chapter CHAPTER 2 --- Cardiovascular Complications of OSAS in Adults (Literature Review) / Chapter 2.1. --- Acute Effects of OSAS on Cardiovascular System --- p.21 / Chapter 2.2. --- Chronic Effects of OSAS on Cardiovascular System --- p.23 / Chapter 2.3. --- Hypertension --- p.24 / Chapter 2.4. --- Heart Failure --- p.28 / Chapter 2.5. --- Pulmonary Hypertension --- p.30 / Chapter 2.6. --- Arrhythmias --- p.31 / Chapter 2.7. --- Cardiac Ischemia and Vascular Disease --- p.33 / Chapter 2.8. --- Stroke --- p.34 / Chapter CHAPTER 3 --- Cardiovascular Complications of Childhood OSAS (Literature Review) / Chapter 3.1. --- Blood Pressure --- p.37 / Chapter 3.2. --- Ventricular Structure and Function --- p.40 / Chapter 3.3. --- Arterial Distensibility --- p.42 / Chapter 3.4. --- Heart Rate Variability --- p.42 / Chapter CHAPTER 4 --- Ambulatory Blood Pressure in Children with OSAS / Chapter 4.1. --- Introduction --- p.44 / Chapter 4.2. --- Methods / Chapter 4.2.1. --- Subjects and Study Design --- p.46 / Chapter 4.2.2. --- Polysomnography (PSG) --- p.47 / Chapter 4.2.3. --- Ambulatory Blood Pressure Measurement (ABPM) --- p.49 / Chapter 4.2.4. --- Statistical Analysis --- p.50 / Chapter 4.3. --- Results / Chapter 4.3.1. --- Subject Characteristics --- p.52 / Chapter 4.3.2. --- Blood Pressure during Wakefulness --- p.55 / Chapter 4.3.3. --- Blood Pressure during Sleep --- p.57 / Chapter 4.4. --- Discussion --- p.62 / Chapter 4.5. --- Conclusion --- p.70 / Chapter CHAPTER 5 --- Cardiac Remodeling and Dysfunction in Children with OSAS / Chapter 5.1. --- Introduction --- p.71 / Chapter 5.2. --- Methods / Chapter 5.2.1. --- Subjects and Study Design --- p.72 / Chapter 5.2.2. --- Polysomnography (PSG) --- p.74 / Chapter 5.2.3. --- Conventional Echocardiography --- p.75 / Chapter 5.2.4. --- Tissue Doppler Imaging --- p.76 / Chapter 5.2.5. --- Statistical Analysis --- p.77 / Chapter 5.3. --- Results / Chapter 5.3.1. --- Study Population --- p.79 / Chapter 5.3.2. --- Polysomnographic Findings --- p.79 / Chapter 5.3.3. --- Echocardiographic Findings / Chapter 5.3.3.1. --- Right Ventricle --- p.81 / Chapter 5.3.3.2. --- Left Ventricle --- p.83 / Chapter 5.3.4. --- Treatment Effect --- p.86 / Chapter 5.4. --- Discussion --- p.90 / Chapter 5.5. --- Conclusion --- p.95 / Chapter CHAPTER 6 --- Conclusion --- p.96 / APPENDIX I Hong Kong Children Sleep Questionnaire (Chinese) --- p.xvii / APPENDIX II Hong Kong Children Sleep Questionnaire (English) --- p.xxii / REFERENCES --- p.xxvii
182

Sleep-disordered breathing in the child and adolescent orthodontic patient

Morton, Paul January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
183

Lipoprotein-associated phospholipase A2 and physical activity in subjects at-risk for obstructive sleep apnea

Ledden, Erin T. 12 August 2011 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science
184

Κατασκευή συστήματος αναγνώρισης άπνοιας σε κινητό τηλέφωνο Android

Κόμπος, Κωνσταντίνος 07 June 2013 (has links)
Αντικείμενο της παρούσας διπλωματικής εργασίας είναι η ανάπτυξη εφαρμογής για λειτουργικό σύστημα Android, για την ανίχνευση της υπνικής άπνοιας. Αρχικά μελετάται η υπνική άπνοια σαν υπνική διαταραχή, οι διάφορες κατηγορίες της, συμπτώματά της και οι τρόποι θεραπείας της. Στη συνέχεια γίνεται αναφορά στις φορητές ηλεκτρονικές συσκευές για τη διάγνωση αυτής της ασθένειας καθώς και τα βασικά κριτήρια που πρέπει να πληρούν οι συσκευές αυτές, όπως αυτά διαμορφώθηκαν από διεθνείς οργανισμούς που ασχολούνται με την μελέτη των ασθενειών του ύπνου. Έπειτα παρουσιάζεται το λειτουργικό σύστημα Android, αναλύεται η αρχιτεκτονική του καθώς και η αρχιτεκτονική των εφαρμογών που Η υπνική άπνοιααναπτύσσονται για αυτό το λογισμικό. Παρουσιάζεται η πλατφόρμα ανάπτυξης Eclipse καθώς και οι επιπρόσθετες δυνατότητες που αποκτά με την προσθήκη του πακέτου Android SDK. Τέλος παρουσιάζονται βασικά παραδείγματα εφαρμογών ώστε να μπορεί ο αναγνώστης να εξοικειωθεί με βασικές δομές που χρησιμοποιήθηκαν για την ανάπτυξη της παρούσας εφαρμογής. Παρουσιάζεται επίσης η λογική της εφαρμογής που αναπτύχθηκε. Βασικές αρχές για την ψηφιακή επεξεργασία σήματος όπως αυτές χρησιμοποιήθηκαν για την επεξεργασία του σήματος της αναπνοής που αναλύεται αυτόματα από την εφαρμογή και τέλος ο μηχανισμός εξαγωγής του τελικού συμπεράσματος, δηλαδή ο τρόπος με τον οποίο η εφαρμογή πραγματοποιεί την τελική της διάγνωση. / The subject of this diploma thesis is the development of an Android application, which is capable to diagnose sleeping apnea. Firstly, there is an extended presentation of sleeping apnea as a sleep disorder. The categories in which sleeping apnea can be divided. Its symptoms and the ways of healing this disorder. Moreover, portable devices for the diagnosis of this disorder are been represented and referred the goals that these devices have to achieve, as they formed by international organizations, which are occupied with the analysis of sleeping disorders. Then the operating system Android is been analyzed, in the domain of its architecture and the structure of an Android application. Furthermore, eclipse IDE is been represented and the further capabilities that it is gain with the installation of the Android SDK. In the last section of this diploma thesis there are some basic example application, which help the primer to acquaint with the structure that are used in the main program of developed application.
185

Sledování mozkové aktivity v prolongované zádrži dechu u freediverů / Prolonged apnea: monitoring brain activity in freedivers

Skopalová, Pavla January 2019 (has links)
Title: Prolonged apnea: monitoring brain activity in freedivers Objectives: The aim of this study is to monitor the brain electrical activity during the prolonged apnea in freedivers. Prolonged apnea in the water and prolonged dry apnea were compared to each other and also to a resting state before the apnea, all states with the eyes closed. Brain activity was obtained from the scalp EEG and evaluated using the sLORETA program. Methods: The research was conducted in 11 healthy men at the age of 23 - 51. The data was obtained from the scalp EEG. The record was first taken at a resting state before the apneas with eyes closed, then at maximum prolonged dry apnea with eyes closed and finally at maximum prolonged apnea in the water with eyes closed. The lenghts of the prolonged apneas ranged from 2:15 minutes to 5:30 minutes in idividual probands. There were pauses of at least three minutes between each apnea as by the proband's needs. The compared pair groups were following: prolonged apnea in the water against prolonged dry apnea, prolonged apnea in the water against resting state before the apnea and finally prolonged dry apnea against resting state before the apnea, all with the eyes closed. Selected sections of EEG record without artefacts were processed by sLORETA program. In the statistical...
186

Estudo cefalométrico de indivíduos com síndrome da apnéia hipopnéia obstrutiva do sono.

Marques, Caroline Gabriele 25 September 2006 (has links)
Made available in DSpace on 2016-01-26T12:51:26Z (GMT). No. of bitstreams: 1 carolinegabrielemarques_tese.pdf: 1078800 bytes, checksum: 0c7b0504e85857d877828a3f432fe74e (MD5) Previous issue date: 2006-09-25 / This study aims to identify associated characteristics of craniofacial skeletal and pharyngeal soft tissues, in lateral cephalometric teleradiography and their possible association with clinical and polyssonographic findings, observing anatomical areas which most influenced the upper airway obstruction. To evaluate a predicting cephalometric pattern for Sleep Apnea Hipopnea Obstructive Syndrome (SAHOS), a sample of 40 subjects was divided into two experimental groups: patients with mild to moderate and severe SAHOS, previously submitted to polyssonographic study, according to their Apnea or Hipopnea Índex (AHI), comparing them with a control group, 10 subjects, with no sleep disorder. The first experimental group had an AHI=15 <30 (moderate sleep apnea). The second group, an AHI> or = 30 (severe sleep apnea). After the results and the statistical methods used to compare the different studied groups, the conclusion was that the SAHOS patients when compared with the control group presented: some positional alterations in their skeletal anatomical structures, mainly a lowering of the hyoide bone in relation to the cervical vertebrae; mandilbular retrusion, increased dimensions of the pharyngeal soft tissues, increased length and width of the soft palate with a decrease of the posterior and superior airway space. / O propósito deste estudo é identificar associação entre as características craniofaciais esqueletais e de tecidos moles em telerradiografias cefalométricas laterais com os dados clínicos e polissonográficos, verificando as áreas anatômicas que mais contribuem para a obstrução das vias aéreas superiores nos pacientes com Síndrome da Apnéia Hipopnéia Obstrutiva do Sono (SAHOS). Para avaliar se existe um padrão cefalométrico previsível para a Síndrome da Apnéia Hipopnéia Obstrutiva do Sono, foram comparadas as diferenças das médias das dimensões esqueléticas craniofaciais e dos tecidos moles da faringe, em norma lateral, de uma amostra de 40 indivíduos, divididos em 2 grupos-teste, com da Síndrome da Apnéia Hipopnéia Obstrutiva do Sono Moderada e Síndrome da Apnéia Hipopnéia Obstrutiva do Sono Grave, previamente submetidos ao estudo polissonográfico e um grupo controle de 10 indivíduos sem a doença. Pertenciam ao primeiro grupo teste os pacientes com Índice de Apnéia e Hipopnéia (IAH) > 15 < 30 (apnéia do sono moderada) e ao segundo grupo teste os pacientes com Índice de Apnéia e Hipopnéia (IAH) &#8805; 30 (apnéia do sono grave). Diante dos resultados obtidos e após a aplicação dos métodos estatísticos usados para comparação dos diferentes grupos estudados, concluiu-se que os pacientes apnéicos quando comparados com o grupo controle apresentaram: alterações no posicionamento das estruturas anatômicas esqueletais, principalmente um posicionamento inferior do osso hióide em relação às vértebras cervicais, retrusão mandibular, dimensões aumentadas dos tecidos moles faringeanos, aumento no comprimento e largura do palato mole com diminuição do espaço aéreo póstero-superior.
187

Effekten av olika hypopné-kriterier med 4% och 3% desaturation på apné/hypopné index / The effect of different hypopnea-criteria with 4% and 3% desaturation on the apnea/ hypopnea index

Al-Daghiree, Jehan January 2020 (has links)
Syfte: Apné/hypopné index (AHI), antalet apnéer/hypopnéer per sömntimma, är den vanligaste parametern som används för att beskriva graden av sömnapné. Syftet med studien är att undersöka effekten av olika hypopnékriterier för AHI, med desaturationsnivå 3% eller 4% d.v.s. om det finns en signifikant skillnad i AHI vid användning av hypopnékriterier 3% jämfört med 4 %. Metod och material: Polygrafiska registreringar från 40 patienter analyserades retrospektivt. Hypopnéer definierades först som 30–90% minskning av luftflödet under &gt;10 sekunder förknippat med 3% desaturation. Därefter definierades hypopnéer med 4% desaturation. Patentregistreringarna tolkades manuellt på Fysiologkliniken vid Västmanlands sjukhus Västerås. Resultat och slutsats: En signifikant skillnad föreligger i AHI vid användning av de olika hypopnékriterierna, (p &lt;0,001). AHI varierade från medianvärdet 8,5 (2,9–17,6) för vid användning av tolkningskriterium 4% desaturation till 15,7 (6,5–24) vid användning av tolkningskriterium 3%. Det är viktig att följa de nya uppdaterade kriterierna från American Academy of Sleep Medicine och Svenska sömnapnéregistret för att kunna ställa rätt diagnos och behandling för patienten. / Purpose: The apnea/hypopnea index (AHI) is the most common parameter used to describe the severity of sleep apnea. The purpose of this study was to examine the effect of different oxygen desaturation levels (3% and 4%) on AHI i.e. if there is a significant difference in the AHI when using different hypopnea-criteria. Method and material: Polygraphic recordings of 40 patients were analyzed retrospectively. Hypopneas were first defined as 30-90% drop in airflow for &gt;10 s associated with 3% oxygen desaturation. Then hypopneas were defined as with 4% oxygen desaturation. Results and conclusion: There is a significant difference in AHI when using different hypopnea criteria, i.e. 4% or 3% desaturation. AHI varied from 8,5 (2,9–17,6) when using hypopnea criteria 4% to 15,7 (6,5–24) when using 3%. It is important to follow the new updated criteria from the American Academy of Sleep Medicine and the Swedish Sleep Apnea Register in order to provide the right diagnosis and treatment for the patient.
188

Procena cerebralne autoregulacije primenom apnea testa kod simptomatske karotidne stenoze pre i posle karotidne endarterektomije / Evaluation of cerebral autoregulation by application of apnea test in patients with symptomatic carotid stenosis before and after carotid endarterectomy

Lučić Prokin Aleksandra 06 November 2015 (has links)
<p>TCD apnea test kao neinvazivna i bezbedna neuroultrasonografska metoda pruža korisne informacije o vazomotornoj reaktivnosti (VMR) u procesu indirektnog sagledavanja funkcionisanja moždane autoregulacije. Vazomotorna reaktivnosti podrazumeva sposobnost dilatacije ili konstrikcije moždanih arteriola nastale kao odgovor na određeni vazoaktivni stimulus, najče&scaron;će ugljen dioksid. Cilj ove doktorske disertacije bio je ispitivanje i analiziranje promene karotidne hemodinamike kod bolesnika sa ishemijskim moždanim udarom (IMU) ili tranzitornim ishemijskim atakom (TIA) i simptomatskom karotidnom stenozom u preoperativnom i tromesečnom postoperativnom periodu, kao i procena revaskularizacionog efekta karotidne endarterektomije (KEA).U istraživanje je uključeno 60 hospitalizovanih bolesnika koji su doživeli prvi IMU i TIA u zoni vaskularizacije arterije cerebri anterior (ACA) i arterije cerebri medije (ACM), svi sa karotidnom stenozom, ACI &ge;70%. Bolesnici su bili hospitalizovani na Klinici za neurologiju, Kliničkog Centra Vojvodine, Klinici za kardiovaskularnu hirurgiju, Instituta za kardiovaskularne bolesti Vojvodine i Klinici za vaskularnu hirurgiju, u Novom Sadu. U odnosu na kliničke manifestacije bolesni i su podeljeni u tri grupe: bolesnici sa TIA i amaurosis fugax, sa parcijalnim infarktom u zoni ACA ili ACM i sa lakunarnim infarktom. Istraživanje je analiziralo uticaj promenljivih i nepromenljivih vaskularnih faktora rizika na pojavu IMU i TIA, ali i na VMR, procenjivanu kroz indeks zadržavanja daha (Breath Holding Index, BHI) ipsilateralno i kontralateralno u odnosu na karotidnu stenozu. Analizirana je povezanost stepena karotidne stenoze sa vrednostima BHI preoperativno, povezanost BHI sa težinom kliničke slike, uticaj kolateralnog krvotoka na VMR, distribucija BHI u pojedinim tipovima IMU i TIA kao i komparacija BHI u pre i u postoperativnom periodu od 30 i 90 dana. Na osnovu sprovedenog istraživanja, do&scaron;lo se do zaključaka da je redukovana VMR preoperativna karakteristika karotidne stenoze ipsilateralno kao i karakteristika različitih tipova IMU i TIA ipsilateralno; postoji negativna korela ija izmeĐu stepena karotidne stenoze i BHI vrednosti. Nije potvrđena hipoteza da veći roj razvijenih kolateralnih puteva uslovljava očuvanu VMR; utvrđena je pozitivna korelacija između BHI vrednosti u preoperativnom i postoperativnom periodu; redukovana VMR ima negativan uticaj na težinu kliničke slike. Prepoznavanje vrednosti TCD apnea testa, koji se može koristiti kao komplementarna metoda drugim vazoaktivnim testovima u praćenju karotidne hemodinamike, od posebne je važnosti neurologu i vaskularnom hirurgu. Time bi se doprinelo daljoj evaluaciji mehanizma nastanka IMU, planiranju terapijskog pristupa i determinisanju prognoze operisanih bolesnika. Činjenica da većina neurolo&scaron;kih odeljenja poseduje TCD aparat, apnea test postaje dostupan svakom neurologu u kliničkom radu, posebno u na&scaron;im uslovima, kada se do drugih drugih, skupljih metoda, te&scaron;ko stiže ili nam ostaju nedostižne.</p> / <p>TCD apnea test, as a noninvasive and safe neuroultrasonographic method, provides useful information about vasomotor reactivity (VMR) in the indirect evaluation of cerebral autoregulation. Vasomotor reactivity is the ability of cerebral arterioles to constrict or to dilate in response to a vasoactive stimulus, mainly carbon dioxide. The aim of this doctoral thesis was to investigate and analyze changes in carotid hemodynamics in patients with ischemic stroke (IS) or transient ischemic attack (TIA) and symptomatic carotid stenosis in the preoperative and three-month postoperative period as well as the assessment of revascularisation effect of carotid endarterectomy (CEA). The study included 60 hospitalized patients who experienced a first ischemic stroke or TIA in the vasularisation area of anterior cerebral artery (ACA) and middle cerebral artery (MCA), all with carotid stenosis &ge;70% ACI. Patients were hospitalized at the Clinic of Neurology, Clinical Center of Vojvodina, Department of Cardiovascular Surgery, Institute of Cardiovascular Diseases and the Department of Vascular Surgery in Novi Sad. Considering clinical manifestations of stroke, the patients were divided into three groups: patients with TIA and amaurosis fugax, with partial infarction in area ACA or ACM and with lacunar infarct. The study analyzed the impact of variabile and unvariable vascular risk factors on the incidence of ischemic stroke and TIA, but also on VMR, evaluated through Breath Holding Index (Breath Holding Index, BHI) on the ipsilateral and contralateral side from carotid stenosis. We analysed the correlation between the degree of carotid stenosis with preoperative values of BHI, BHI correlation to the severity of clinical findings, the impact of collateral circulation to the VMR, distribution of BHI in certain types of ischemic stroke and TIA as well as comparison of BHI in the pre and postoperative period of 30 and 90 days. On the basis of this research came the conclusion that reduced VMR is characteristic of ipsilateral carotid stenosis in preoperative period as well as number of developed collateral characteristics of different types of ipsilateral ischemic stroke and TIA; there is a negative correlation between the degree of carotid stenosis and BHI values. The hypothesis that the greater pathways causes preservation of VMR was not confirmed, while the positive correlation between BHI values in the preoperative and postoperative period was established. Reduced VMR has a negative impact on the degree of clinical picture severity. Recognizing the importance of TCD apnea test method, that can be used as a complementary method to other vasoactive tests in monitoring of carotid hemodynamics, is of special importance to the neurologists and vascular surgeons. This would contribute to the further evaluation of mechanism of ischemic stroke, planning of therapeutic approach and determining the prognosis of treated patients. The fact that most of neurological department has TCD device, apnea test becomes available to every neurologist in clinical work, specially in our conditions, when other methods remain unattainable.</p>
189

Efeito da apneia obstrutiva do sono na audição de adultos / Effects of obstructive sleep apnea in adult hearing

Matsumura, Erika 07 June 2016 (has links)
Introdução: A apneia obstrutiva do sono (AOS) provoca modificações na arquitetura normal do sono, fragmentando-o de forma crônica com hipóxias intermitentes levando, a longo prazo, a sérias consequências na saúde. Acredita-se que a ocorrência de eventos respiratórios durante o sono como apneia e hipopneia pode prejudicar o mecanismo de transdução da orelha interna e a transmissão de impulsos nervosos ao longo da via auditiva que são altamente dependentes do fornecimento do oxigênio. Contudo, essa associação não se encontra bem estabelecida na literatura. Adicionalmente, sujeitos com AOS poderiam apresentar alterações na função de transferência acústica da orelha média devido ao desequilíbrio pressórico existente nas vias aéreas superiores durante o sono, característico da fisiopatologia da doença. Objetivo: Comparar os achados da avaliação auditiva entre os indivíduos portadores e não portadores de AOS. Método: A casuística foi composta por 38 adultos do sexo masculino, média de idade de 35,8 (±7,2) e foram divididos em quatro grupos experimentais pareados por idade e índice da massa corpórea. Os grupos foram classificados com base na polissonografia em: controle (n=10), AOS leve (n=11), AOS moderada (n=8) e AOS grave (n=9). Todos os sujeitos do estudo negaram história pregressa de risco para perda auditiva. Todos os sujeitos foram submetidos à audiometria convencional, timpanometria, pesquisa de reflexos acústicos ipsi e contralaterais, imitância acústica de banda larga com estímulo clique de 226 a 8000 Hz para obtenção da energia de absorvância (EA), emissões otoacústicas por produto de distorção e potenciais evocados auditivos de tronco encefálico. Os resultados foram submetidos às análises estatísticas e o nível de significância adotado foi de 5% para todos os testes. Resultados: As medidas da EA não mostraram diferença significante entre os grupos quando considerados somente o fator grupo (sem AOS, AOS leve, moderada e grave). Para o efeito de interação entre os fatores grupo e frequência, o valor da média da EA do grupo com AOS de grau moderado foi significativamente maior do que do grupo com AOS de grau leve (p=0,003) em 8000 Hz. O grupo com AOS de grau grave apresentou menores valores das médias das amplitudes das EOAPD quando comparados aos dos grupos controle, AOS de grau leve e AOS de grau moderado (p=0,02, p=0,03 e p=0,01, respectivamente). Não houve diferença significante nos valores das latências absolutas das ondas I, III e V, e interpicos I-III, III-V e I-V entre os grupos. Observou-se associação entre a presença da AOS e alteração da latência absoluta da onda V (p=0,03). Foi observada associação entre AOS de grau moderado e alteração da latência da onda V (p=0,01). Conclusão: A presença da AOS está associada à presença de alteração na condução nervosa do estímulo acústico na via auditiva em tronco encefálico. A presença de AOS de grau grave prejudicou a função coclear. De maneira geral, a função de transferência acústica da orelha média é similar entre os adultos com e sem AOS / Introduction: The obstructive sleep apnea (OSA) can change the normal sleep architecture, fragmenting it chronically with intermittent hypoxias and, to the long time, inducing to serious consequences to health. It is believed that the occurrence of respiratory events during sleep with the presence of apnea and hipopneia can damage the transduction mechanism of the inner ear and nerve impulses transmission along the auditory pathways, which are highly dependent on the oxygen supply. However, this association is not well established. Moreover, the acoustic transference function of middle ear could show alterations, due to the pressure changes that occur in upper airway during the sleep, typical of OSA pathophysiology. Objective: To compare the findings of the hearing evaluations between subjects with OSA and without OSA. Method: A total of 38 subjects of the male sex, mean age 35.8 (±7.2), were divided into four groups, which were matched for age and body mass index. The groups were classified by the means of polissomnography in without OSA (n=10), mild OSA (n=11), moderate OSA (n=8) and severe OSA (n=9). All the subjects denied a history of risk for hearing loss. These subjects were submitted to: conventional audiometry, tympanometry, ipsilateral, contralateral acoustic reflex, wideband acoustic immittance for measurements of energy of absorbance (EA) with click stimulus of 226 to 8000 Hz, distortion product of otoacoustic emissions (DPOAE) and click evoked auditory brainstem responses (ABR). The recorded data of each analysis were conducted to an appropriate statistical test and was adopted the significant level of 5% for all the tests. Results: The EA data did not showed statistical differences among the groups when considering only the OSA severity factor (without, mild, moderate or severe). For the interaction between OSA severity and frequency factors, the mean value of EA of moderate OSA group was significant higher than the mild OSA group (p=0.003) in 8000 Hz. The severe OSA group presented lower mean values of amplitudes of DPOAE when compared to the control group, mild and moderate OSA groups (respectively, p=0.02, p=0.03 and p=0.01). For ABR, no differences was observed in latencies waves I, III and V, and interpeaks I-III, III-V and I-V values among the groups. Conclusion: The presence of OSA is associated with the presence of alterations in the nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The presence of severe OSA impaired the DPOAE responses. In general, the acoustic transference function of middle ear is similar between the adults with and without OSA
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Effect of intermittent hypoxia on hippocampal long-term synaptic plasticity in mouse.

January 2008 (has links)
Xie, Hui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 91-116). / Abstracts in English and Chinese. / CONTENTS --- p.I / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.ii / 中文摘要 --- p.v / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Overview of the Study --- p.1 / Chapter 1.2 --- Obstructive Sleep Apnea --- p.4 / Chapter 1.2.1 --- Epidemiology --- p.5 / Chapter 1.2.1.1 --- Prevalence --- p.5 / Chapter 1.2.1.2 --- Risk Factors --- p.6 / Chapter 1.2.2 --- Pathogenesis --- p.8 / Chapter 1.2.3 --- Pathophysiologic Consequences --- p.9 / Chapter 1.2.4 --- Diagnosis --- p.12 / Chapter 1.2.5 --- Treatment --- p.13 / Chapter 1.3 --- Memory and Long-term Potentiation --- p.15 / Chapter 1.3.1 --- Memory --- p.15 / Chapter 1.3.1.1 --- Classification of Memory --- p.15 / Chapter 1.3.1.1 --- Physiology of Memory --- p.17 / Chapter 1.3.2 --- Hippocampus --- p.18 / Chapter 1.3.2.1 --- Anatomy --- p.18 / Chapter 1.3.2.2 --- Hippocampus and Memory --- p.20 / Chapter 1.3.3 --- Long-term Potentiation (LTP) --- p.20 / Chapter 1.3.3.1 --- Discovery of LTP --- p.21 / Chapter 1.3.3.2 --- Types of LTP --- p.22 / Chapter 1.3.3.3 --- Properties of NMDA-LTP --- p.23 / Chapter 1.3.3.4 --- Early Phase LTP and Mechanism --- p.24 / Chapter 1.3.3.5 --- Late Phase LTP and Mechanism --- p.28 / Chapter 1.3.3.6 --- Important Factors in Long-term Potentiation --- p.29 / Chapter 1.4 --- Brain-derived Neurotrophic Factor (BDNF) --- p.33 / Chapter 1.4.1 --- Neurotrophins --- p.33 / Chapter 1.4.2 --- Structure and Expression of BDNF --- p.36 / Chapter 1.4.3 --- BDNF and Synaptic Plasticity --- p.37 / Chapter 1.4.3.1 --- BDNF and E-LTP --- p.38 / Chapter 1.4.3.2 --- BDNF and L-LTP --- p.39 / Chapter CHAPTER 2 --- METHODS --- p.43 / Chapter 2.1 --- Animal model of Obstructive Sleep Apnea --- p.43 / Chapter 2.1.1 --- Chronic Intermittent Hypoxia --- p.43 / Chapter 2.1.2 --- Bodyweight During Hypoxia Treatment --- p.47 / Chapter 2.2 --- Electrophysiological Experiments --- p.47 / Chapter 2.2.1 --- Brain Slice Preparation --- p.47 / Chapter 2.2.2 --- Multi-electrode Recording Setup (MED64) --- p.48 / Chapter 2.2.3 --- Slice Superfusion --- p.51 / Chapter 2.3.4 --- Field Potential Recordings --- p.53 / Chapter 2.3.5 --- LTP Induction Protocol --- p.55 / Chapter 2.3 --- Stereotaxic Surgery --- p.57 / Chapter 2.4 --- Drugs and Data Analysis --- p.58 / Chapter CHAPTER 3 --- RESULTS --- p.59 / Chapter 3.1 --- Validation of the OSA model --- p.59 / Chapter 3.2 --- Optimization for Studies of Early and Late-phase LTP by MED64 --- p.60 / Chapter 3.2.1 --- Optimization of Brain Slices --- p.60 / Chapter 3.2.2 --- Optimization of Field Potential Recording --- p.62 / Chapter 3.2.3 --- Optimization for LTP Study --- p.65 / Chapter 3.3 --- Effect of Intermittent Hypoxia on Hippocampal LTP --- p.68 / Chapter 3.3.1 --- Early-phase LTP (E-LTP) --- p.68 / Chapter 3.3.2 --- Late-phase LTP (L-LTP) --- p.71 / Chapter 3.4 --- Effect of BDNF on Intermittent Hypoxia-induced LTP Impairment --- p.75 / Chapter 3.4.1 --- BDNF Rescues LTP Impairment --- p.75 / Chapter 3.4.2 --- BDNF prevents LTP Impairment --- p.78 / Chapter CHAPTER 4 --- DISCUSSION --- p.80 / Chapter 4.1 --- Chronic Intermittent Hypoxia Model of OSA in Mice --- p.80 / Chapter 4.2 --- Impairment of LTP Induced by Intermittent Hypoxia --- p.82 / Chapter 4.3 --- The role of BDNF in IH-induced Impairment in Hippocampal Synaptic Plasticity --- p.84 / Chapter 4.4 --- Future Studies --- p.89 / REFERENCE --- p.91

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