Thesis (M.P.H.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 96-110).

Thesis (MSocSc)--University of South Australia, 1995

When gas is inspired into the lungs it mixes with the gas left in the lungs at the end of the previous expiration. In health, this mixing is relatively efficient but in disease this gas mixing is impaired. Impairment of mixing is brought about by two processes, a maldistribution of inspired gas into a parallel system, or an inhibition of diffusion. The aim of this thesis was to illuminate the contributions made by these two processes to this impairment. This was done by investigating single and multi-breath alveolar mixing efficiency (AME) in never smokers and patients with chronic airway disease and by the use of mathematical models. Both indices of alveolar mixing efficiencies were found to be reproducible in never smokers and patients, AME(mb) and AME(sb) were both significantly lower in patients than in never smokers. A two-compartment parallel model was devised to evaluate the contribution of regional inhomogeneity. This showed that the only way both values of AME(sb) and AME(mb) could be reproduced was to include a component of diffusion limitation. Another model was devised to evaluate the contribution of diffusion limitation to mixing impairment. This model proved to be inadequate to permit any conclusions. The work presented in this thesis suggests that gas mixing impairment results from a maldistribution of inspired gas and gaseous diffusion limitation with the latter playing the most significant role in the generation of the alveolar slope, more especially in diseased lungs.

The objective of this project was to investigate and determine the association between hospitalizations of respiratory diseases with one another and with isolations of viral infections in five age groups. Weekly data on all hospitalizations in Ontario, Canada, from week 14 of 2001 to week 13 of 2003 were obtained for 5 age groups (under 2 years, 2 to 4 years, 5 to 15 years, 16 to 49 years and over 50 years inclusive) for respiratory diseases including, asthma, respiratory tract infection (RTI) and chronic obstructive pulmonary disease (COPD)1. Furthermore, data for viral infections including influenza virus type A and type B (Flu AB) and respiratory syncytial virus (RSV) isolations were also obtained from Health Canada for the same weekly time periods. In order to test for independence and determine a relationship, if any, between hospitalizations of respiratory diseases with one another and with isolations of viral infections, structural time series models were developed for all age groups of the respiratory diseases and explanatory variables were modeled accordingly against the hospital admission counts for the respiratory diseases. These explanatory variables include, other respiratory diseases, viral infections, and lagged values of the dependent variable. Neither FLU AB nor RSV showed a significant relationship with asthma patients of all ages. Weekly RSV peaks coincided with RTI patients under 2 years and RTI peaks in patients 5 to 15 years preceded FLU AB peaks. A relationship between all three respiratory diseases, asthma RTI and COPD, was discovered for all age groups. Peaks of asthma coincided with various transformations of RTI peaks for the five age groups and peaks of COPD coincided with both the untransformed asthma and RTI peaks in patients over 50. For all other relationships, the null hypothesis of independence was accepted. These findings suggest that there is a strong association between respiratory diseases and that children and adults with respiratory diseases respond differently to viral infections. 1 Only data for patients over 50 years was obtained for COPD. / Thesis / Master of Science (MSc)

No description available.

No description available.

MSc (Med) (Pharmaceutical Affairs), Faculty of Health Sciences, University of the Witwatersrand / Fifteen traditional medicinal plants, indigenous to southern Africa, that are used to treat various respiratory ailments were screened for their antimicrobial activity and their chemical profiles were documented. Acetone:methanol (1:1) extracts were prepared from the leaves, stems, roots, barks and thorns of the investigated plant species. The antimicrobial activity was determined against pathogens associated with respiratory conditions i.e. Moraxella catarrhalis, Bacillus cereus, Enterococcus faecalis, Klebsiella pneumoniae, Staphylococcus aureus, Candida albicans and Cryptococcus neoformans. The MIC values ranged from 0.08 mg/ml to 12 mg/ml. The two pathogens against which the most number of extracts obtained MIC values that were ≤ 1 mg/ml were Moraxella catarrhalis (68% of the extracts) and Bacillus cereus (56% of the extracts). The plant extracts that obtained the five lowest average MIC values against the respiratory pathogens were the root extracts of Terminalia sericea (0.69 mg/ml), leaf and stem extract of Chenopodium ambrosioides (1.04 mg/ml), leaf, stem and flower extract of Leucas martinicensis (1.10 mg/ml), leaf extract of Zanthoxylum davyi (1.29 mg/ml) and the leaf and stem extracts of Lantana rugosa (1.32 mg/ml). For the bioautographic assays, clear zones of inhibition were recorded for Lantana rugosa (leaves and stems) and Vitex rehmannii (leaves) against Staphylococcus aureus and Moraxella catarrhalis. The root extract of Ziziphus mucronata had a clear zone of inhibition against Staphylococcus aureus. The leaf and stem extracts of Chenopodium ambrosioides had a clear zone of inhibition against Moraxella catarrhalis. The chemical profiles that were recorded for the plant extracts comprised of HPLC and TLC chromatograms. The HPLC and TLC profiles resulted in the separation of the chemical constituents thus providing a chemical fingerprint for the plant extracts. Flavonoids were tentatively identified for Acacia sieberiana (leaves), Alepidea amatymbica (roots), Clematis oweniae (leaves), Clerodendrum glabrum (leaves), Heteromorpha arborescens (bark), Peucedanum caffrum (roots B), Vitex rehmannii (leaves) and Ziziphus mucronata (leaves). The TLC chromatograms qualitatively displayed good separation of the compounds present in the plant extracts. The antimicrobial activity recorded for the plant extracts validates their traditional uses to treat various respiratory infections and the chemical profiles provide a reference of the chemical profiles of the plant extracts that can be used in future investigations

Thesis (Ph. D.)--University of Adelaide, Dept. of Community Medicine, 1988. / Includes bibliographical references (leaves 215-236).

A tuberculose continua sendo um grave problema de saÃde pÃblica. A morbidade e mortalidade por todas as formas de apresentaÃÃo da doenÃa tem aumentado nos Ãltimos anos. Os SintomÃticos RespiratÃrios (SRâS) tÃm papel importante como indicadores de programaÃÃo das aÃÃes de controle. No presente trabalho, foi efetuado um estudo transversal, com o objetivo de conhecer o percentual de SR na populaÃÃo maior de 14 anos, que demanda os ServiÃos de SaÃde em Fortaleza. Os resultados mostram que, do total de 1200 consultantes, 23,58% sÃo SRâs com qualquer tempo de duraÃÃo dos sintomas e 6,50% com o tempo de 3 semanas e mais. O percentual de SRâs variou de 4,5% a 9,5% nas diferentes regiÃes de Fortaleza, bem como variou de 5,1% a 20,5% em diferentes grupos etÃrios. Dos SRâs, detectados com sintomas de 3 semanas e mais, 70,5% procuraram o Centro de SaÃde por outras razÃes que nÃo os sintomas respiratÃrios. / The Tuberculosis is still a serious Public Health problem. The Morbidity and Mortality for all the forms of the diseases has been increasing in the last years. The Respiratory Symptomatic (RS) have an important role as indicators of the programmatic control actions. In the present work a transversal study was carried out. study, aiming to determine the percentage of SR in the population older than 14 years old that seek the Public Health Services in Fortaleza. The results demonstrate that a total of 1200 patients, 23,58% were RS with any time of duration of the symptoms and 6.50% with the time of 3 weeks or more. The percentage of RS ranged from 4,5% to 9,5% in the different regions of the Fortaleza City, as well as from 5,1% to 20,5% in different age groups. From the detected RS with symptoms of 3 weeks of duration time or more, 70.5% went to the Health Center for reasons other than respiratory symptoms.

Yes / Conference abstract