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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.
61

Use of a sternal elevator to reverse complete airway obstruction secondary to anterior mediastinal mass in an anesthetized child

Linnaus, Maria E., Morray, Jeffrey, Bae, Jae-O, Fraser, Jason D. 05 1900 (has links)
Patients with an anterior mediastinal mass pose significant risk for cardiorespiratory compromise during surgical procedures and general anesthesia. Several techniques have been described to reverse airway obstruction in these patients. In extreme circumstances, patients may require cardiac bypass or extracorporeal membrane oxygenation (ECMO) until definitive treatment of the mass and patient stabilization is achieved. We present a case in which the RulTract (R) system was used for emergency sternal elevation as a bridge to ECMO in acute respiratory collapse in an 11-year-old female with a minimally symptomatic anterior mediastinal mass. (C) 2016 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
62

Cephalometric airway measurements in class III skeletal deformity

鄧樹森, Tang, Shu-sum. January 2000 (has links)
published_or_final_version / Dentistry / Master / Master of Dental Surgery
63

Mechanisms of airway protection in ageing and Parkinson's disease

Leow, Li Pyn January 2007 (has links)
Safe and efficient swallowing requires integrity of both motor and sensory systems. Prior studies have established that motor impairment in individuals with PD frequently manifests as abnormalities in swallowing biomechanics. In contrast, very few studies have investigated the contribution of sensory impairment towards pharyngeal biomechanics and airway protection in this patient cohort. This area should be addressed in light of evidence that the severity of limb motor dysfunction in PD does not reliably predict severity of dysphagia. Emerging data suggests that dysphagia in PD cannot be solely attributed to motor impairment, but may also be influenced by deficits in sensory aspects of airway protection. As an example, silent aspiration in up to 100% has been reported in individuals with PD due to laryngopharyngeal sensory deficits have. Even so, current research lacks information on the integration of both motor and sensory components that make up the swallowing process. The aim of this study was to document changes in airway protection with age, in PD and across severity levels of PD. The project was comprised of two parts. In part one, three parallel studies were conducted to assess a series of both motor and sensory airway mechanism (Chapters 4 to 9). In the first study, 16 young (8 males, age range 21.3 - 32.4) and 16 elder adults (8 males, age range 61.5 - 84.7), were assessed to investigate changes in airway protection that accompany ageing. In the second study, data from individuals diagnosed with PD across severity levels (Hoehn-Yahr 1 - 4, age range 64.2 - 84.5) were age and gender-matched to 16 healthy elders in order to examine the effects of PD on airway protection. In the third, the impact of disease severity was studied with data from 16 individuals in the earlier stages (Hoehn-Yahr ≤ 2, 13 males, age range 51.3 - 82.5, ) compared to 16 individuals in the later stages (Hoehn-Yahr ≥ 2.5, 10 males, age range 61.5 - 78.9). In part two of this project, two smaller, pilot studies were completed to probe the influence of pharmacologic and behavioural treatments on airway protection mechanisms. In the first pilot study, the effect of pharmacotherapy on airway protection was investigated in 10 patients 'on' and 'off' levodopa (Chapter 10). In the second study, 5 patients were assessed before and after completing the Lee Silverman Voice Treatment (LSVT) to document effects of speech rehabilitation on airway protection (Chapter 11). Multimodality assessment elicited data from all participants on both motor and sensory components of airway protection (Chapter 3). Specifically, breathing-swallowing coordination (BSC) and swallowing apnoea (SA) were captured using simultaneous directional nasal airflow and surface electromyography (sEMG). Standard, closed-loop spirometry was used to assess pulmonary function. Swallowing biomechanics were screened using a validated timed test of swallowing efficiency and further evaluated using fibreoptic endoscopic evaluation of swallowing (FEES). Finally, chemo-sensation of the laryngopharynx was determined with the administration of the inhalation cough challenge while mechanosensation was examined using FEES. Results suggest that motor control for airway protection is reasonably robust in PD, although sensory response is impaired. The predominant pattern for swallowing respiratory coordination was mid-expiration for all participants regardless of age and disease severity (Chapter 4). Individuals with PD demonstrated a reduction in average time and volume per swallow, leading to an overall decrease in swallowing capacity (Chapter 5). No difference was found for swallowing efficiency between those in early and later stages of PD. Pulmonary function measures were not significantly different as a function of age, PD or PD severity (Chapter 6). In summary, results from motor assessments contributing to airway protection support the robustness of breathing-swallowing coordination (BSC) and pulmonary function across research groups, but identify a reduction in overall swallowing efficiency in PD. Results from sensory assessments contributing to airway protection revealed that chemosensation was not different between age groups but base of tongue mechano-sensation was diminished in individuals with PD. Natural cough thresholds did not differ between young adults and elders but when asked to stifle coughing, elders were less able to do so compared to young adults (Chapter 7). For the first time, a reduction in mechano-reception at the base of tongue was recorded in individuals with PD (Chapter 8). These patients also demonstrated increased post swallow residual (Chapter 5), which offers an explanation for the complaint of globus in this population. These assessments highlight some compromise to sensory aspects of airway protection in PD. Overall, dysphagia had a negative impact on the quality of life of individuals with PD and even more as disease severity progresses (Chapter 9). Results from part two of the study looking at the effects of therapeutic interventions on airway protection revealed some unexpected findings. In chapter 10, results showed a reduction in pulmonary function when 'on' levodopa, but no differences in swallowing efficiency, BSC, or laryngopharyngeal chemo- and mechano-reception were observed. These results suggested a reduction in pulmonary function with levodopa without any increase in risk of airway protection compromise1. Unexpectedly and documented for the first time, the percentage of post swallow inspiration increased after LSVT (Chapter 11) but as with the levodopa study, this was also not accompanied by any apparent increase in aspiration risk. An increase in submental surface electromyography (sEMG) amplitude across all 5 participants may serve as a proxy measure of improvement in hyolaryngeal excursion. Finally, participants reported an overall improvement in social functioning and communication after LSVT. In conclusion, this study provided evidence that mechano-sensory aspect of airway protection is diminished in individuals with PD, possibly compromising airway protection. Patients not only demonstrated increased residue but the lack of sensation may prevent clearing or spontaneous multiple swallows. Overall, airway protection is maintained in ageing but swallowing efficiency declines in the presence of PD. This study contributes significantly to current research efforts in PD by expanding on existing reports regarding motor aspects of airway protection. Specifically, BSC, swallowing efficiency and evaluation of biomechanics using FEES research have never before been investigated exclusively in the PD population. Finally, the chemo- and mechano-sensation evaluated in this study are an important addition to the limited evidence that sensory impairment in individuals with PD potentially compromises airway protection. Results of the present study will serve as a platform upon which future studies may compare and expand.
64

An epidemiological investigation of respiratory disease in racehorses

Wood, James Lionel Norman January 1999 (has links)
No description available.
65

GM-CSF and eosinophil survival in asthma

Hallsworth, Matthew Pearce January 1999 (has links)
No description available.
66

The assessment of the soft palate in habitual snorers and its modification by laser palatoplasty

Badawey, Mohamed Reda El January 2001 (has links)
No description available.
67

Avaliação da via aérea do paciente obeso para predição da dificuldade de intubação traqueal : efeito da manipulação laríngea /

Cerqueira, Bruno Gardélio Pedreira de. January 2009 (has links)
Orientador: Eliana Marisa Ganem / Banca: Norma Suely Pinheiro Módulo / Banca: Tânia Mara Vilela Abud / Resumo: A dificuldade na intubação traqueal é causa de mortalidade em anestesiologia e pode estar relacionada à obesidade. Reconhecer o paciente com intubação difícil contribui para o sucesso da abordagem da via aérea, contudo os parâmetros preditores de intubação difícil não estão bem estabelecidos. A classificação de Mallampati, a distância interincisivos, a circunferência do pescoço, a distância tireomentoniana, a conformação da face e a presença da síndrome da apnéia obstrutiva do sono são parâmetros que podem indicar a intubação difícil. A manobra de BURP tem por objetivo melhorar a visualização da via aérea durante a laringoscopia e variações da mesma também podem ser efetivas. Assim, o objetivo desta pesquisa foi correlacionar os parâmetros acima descritos com a dificuldade de intubação traqueal observada durante a laringoscopia, avaliada por meio da escala de Cormack e Lehane (ECL), sem e com manipulação de laringe (variação da manobra de BURP). Cento e trinta e quatro pacientes de ambos os sexos, foram avaliados no período pré-operatório, quanto ao índice massa corpórea, a classificação de Mallampati, a circunferência do pescoço, a distância interincisivos, a distância tireomentoniana e o grau da síndrome da apnéia obstrutiva do sono. Após a monitorização, o posicionamento adequado e a indução anestésica os pacientes foram submetidos à laringoscopia direta, sendo avaliado o grau da escala de Cormack e Lehane. Nos pacientes com graus superiores a um, realizou-se a manipulação da laringe, reavaliando-se o grau da mesma. A manobra de manipulação da laringe é variação da de BURP e consiste no deslocamento da laringe pelo anestesiologista que esta Introdução e Objetivo 9 realizando a laringoscopia, sem um direcionamento pré-estabelecido. Foram registrados os graus da... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The difficulty in tracheal intubation is a cause of mortality in anesthesiology and can be associated with obesity. To be able to recognize a patient of difficult intubation may add to the success of the airway approach; however, parameters used to predict difficult intubations are not well established. Mallampati's classification, the distance between incisive teeth, neck circumference, thyroid-chin distance, facial shape and the presence of sleep apnea syndrome are parameters that can point towards a challenging intubation. BURP's maneuver aims at improving airway visualization during laryngoscopy and its variations may also be effective. Thus, the goal of the present study is to correlate the aforementioned parameters with the difficulties associated with tracheal intubation observed during laryngoscopy, evaluated by means of Cormack and Lehane's scale, with and without laryngeal handling (BURP's maneuver variation). One hundred and thirty four patients from both genders were assessed in the pre-operative time as to body mass index, Mallampati's classification, neck circumference, distance between incisive teeth, thyroid-chin distance and the level of obstructive sleep apnea. After monitoring, proper positioning and anesthetic induction, the patients were submitted to direct laryngoscopy, and we assessed their classification according to Cormack and Lehane's scale. In those patients classified above level one, we manipulated their larynx and reassessed their classification. Laryngeal manipulation maneuver is a variation of BURP's maneuver and is based on laryngeal shifting by the anesthesiologist who is doing the laryngoscopy, with no pre-established direction. We recorded the patient's classifications according to Introdução e Objetivo 11 Cormack and Lehane's scale ...(Complete abstract click electronic access below) / Mestre
68

The role of Yap in lung development

Mahoney, John Edmund 22 January 2016 (has links)
The mechanisms by which epithelial progenitor cells integrate local signals to balance proliferation with differentiation and regulate patterning during lung organogenesis are still poorly understood. The Hippo pathway and its transcription co-activator Yap have recently emerged as major regulators of progenitor cell expansion and differentiation in development and cancer. Here we investigated the role of Yap signaling in the cellular and molecular events associated with lung epithelial morphogenesis and differentiation. We provide evidence that when airway epithelial tubules are forming and branching, a nuclear to cytoplasmic shift of Yap marks the boundary between the progenitors of the distal lung and the airway compartment. At this transition zone, Yap specifies a transcriptional program that controls the expression of Sox2, restricting distal gene expression and initiating an airway progenitor cell program key to generate the airway epithelium and its branched tubular structures. In Yap deficient mice, epithelial progenitors are unable to properly respond to local Tgf beta-induced cues to control levels and distribution of Sox2, resulting in expansion of the distal epithelial compartment and inability to form airways. Moreover, we show that Yap levels and phosphorylation status play a major role in regulating differentiation of airway progenitors later in development and in adult life. Analysis of YAP-interacting partners in adult airway progenitors by Mass Spectroscopy suggests phosphorylated Yap interactions with ciliome proteins. Our study reveals a crucial role for Yap in specification and differentiation of airway progenitors likely to be also relevant in regeneration-repair of the adult airway epithelium.
69

The airway transcriptome as a measure of injury response to and recovery from smoking and alternative tobacco products

Hijazi, Syeda Kahkeshan 12 March 2016 (has links)
Tobacco smoke remains a major public health concern and a factor contributing to the development and progression of various lung diseases world-wide. Smoking cessation can significantly reduce the risk of developing smoking-related diseases, although some smokers remain at an elevated risk despite quitting. Here, I used high-throughput genomic technologies to pave the way for understanding the transcriptomic response in airway epithelium to tobacco exposure, smoking cessation and potentially reduced exposure products (PREP). First, using a longitudinal dataset of nasal airway epithelial cells obtained from active smokers enrolled in smoking cessation programs over 24 weeks, I demonstrated that tobacco-related alterations in the airway gene expression are rapidly reversed within 4 to 8 weeks following smoking cessation. Genes with different biological functions revert towards baseline with different dynamics following smoking cessation. These findings suggest that the nasal-epithelium can serve as a minimally-invasive site to measure the reversible impact of smoking. Secondly, using a dataset of nasal airway epithelial cells from active smokers who switched to potentially reduced exposure products (PREP) for 6 weeks, I showed that gene expression differences induced by switching to PREP may only constitute a partially reduced exposure relative to smoking cessation. My results demonstrate that the nasal-epithelium can also serve as a minimally-invasive site to measure the responses to PREP and may ultimately yield biomarkers to evaluate the potential disease risks associated with these products. Lastly, using small RNA-seq data from bronchial epithelial cells of smokers, I found alterations in airway micro-RNA expression that associate with time since quitting in former smokers. These studies have provided novel insights into the physiologic responses of the airway epithelium to tobacco smoke and PREP and may ultimately serve as a useful approach for evaluating the disease risks associated with changes in smoking behavior. This work sets the stage for additional studies aimed at identifying prevention strategies that decrease the persistent risk of smoking-related lung disease in former smokers and identify biomarkers to assess lung disease risk in former smokers. / 2016-12-31T00:00:00Z
70

Defining the molecular and cellular mechanisms regulating Aspergillus fumigatus regulated airway wall remodelling in asthma

Labram, Briony January 2017 (has links)
Asthma is a common chronic inflammatory condition which affects over 300 million people worldwide. Thickening of the subepithelial layer is a key feature of asthmatic airways and the extent of thickening has been correlated with severity of asthma and increased exacerbations. Recent epidemiological studies have shown a link between fungal sensitisation primarily with Aspergillus fumigatus (A. fumigatus) and exacerbations of asthma leading to increased morbidity and mortality. The airway epithelium acts as an initial defence barrier to inhaled allergens such as A. fumigatus and emerging evidence suggests that as well as orchestrating an allergic immune response, it initiates aspects of airway wall remodelling including subepithelial thickening. However, induction of a profibrogenic response by the airway epithelium following exposure to inhaled fungi associated with severe asthma has not been well documented. The epithelial expression and production of the profibrotic growth factors, TGF-β1, TGF-β2, IL-6, endothelin-1 and periostin, selected as implicated in the aetiology of asthma and their profibrotic activity, were investigated in response to both A. fumigatus spores and culture filtrate in vitro. Furthermore, in vivo chronic inhalation models using either live spores or culture filtrate from two different strains of A. fumigatus (AF293 and CEA10) were used to determine the ability of the fungi to induce murine airway wall remodelling. In vitro, spores from both strains were able to induce the expression and production of IL-6 and endothelin-1 from human bronchial epithelial cells but none of the other profibrotic growth factors. In vivo, despite spores from both strains inducing expression and production of IL-6 and endothelin-1, only CEA10 spores caused significant subepithelial collagen deposition however, both strains induced α-SMA, a myofibroblast and smooth muscle marker around the airways. As a secreted factor was suspected of driving airway wall remodelling, subsequent studies used culture filtrate produced by the two strains, AF293, a low and CEA10, a high protease producer in basal medium. Only AF293 culture filtrate induced IL-6 and endothelin-1 from human bronchial epithelial cells in vitro. However, in vivo, culture filtrate from both strains was able to induce IL-6 and endothelin-1 expression, with AF293 causing a more profound subepithelial collagen deposition and significantly increased α-SMA abundance. It was hypothesised that epithelial-derived endothelin-1 drives airway wall remodelling and hence Endothelin receptor A was inhibited in the in vivo culture filtrate inhalation model. A significant reduction in subepithelial collagen deposition and α-SMA localisation around the airways was demonstrated in mice receiving an Endothelin receptor A antagonist compared with culture filtrate alone. This thesis indicates that A. fumigatus exposure can drive features of airway wall remodelling such as subepithelial fibrosis possibly through the epithelial production of profibrotic growth factor, endothelin-1.

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