This thesis describes the cultivation and extraction of filamentous fungi isolated from extreme environments in the search for new antibiotic compounds. Filamentous fungi are a rich source of medicines including antibiotics, and it is believed that many currently unknown fungal species and bioactive fungal metabolites remain to be discovered. Aspergillus fumigatus and Penicillium nalgiovense strains were isolated from an antibiotic-contaminated riverbed near Hyderabad, India, and soil taken from a penguin’s nest on Paulete Island, Antarctica, respectively. It was anticipated that the extreme conditions within these environments would exert unusual selective pressures on their filamentous fungi, possibly causing the secretion of new bioactive compounds. The cultivation, extraction and analysis of metabolites from the A. fumigatus strain resulted in the isolation of the antimicrobial substance gliotoxin. Subsequent investigations revealed that this strain’s secretion of gliotoxin was increased by as much as 65 % when it was cultivated in the presence of pathogen-associated molecular patterns. These results indicate the existence of a fungal receptor/signaling system for detecting nearby bacteria. The scope for using gliotoxin and the related metabolite bis(methyl)gliotoxin as biomarker metabolites for diagnosing the lethal pulmonary condition invasive aspergillosis was also investigated. Bronchoalveolar lavage fluid from 42 patients with and without possible invasive aspergillosis was extracted and analyzed. The results obtained suggest that gliotoxin and bis(methyl)gliotoxin are not suitable markers for diagnosing invasive aspergillosis. Studies on the P. nalgiovense strain from Antarctica resulted in the isolation of the antifungal agent amphotericin B. The secretion of this compound increased when P. nalgiovense was cultured on a potato-dextrose agar enriched with coconut flakes rather than liquid RPMI 1640 medium. This was the first time amphotericin B was isolated from any organism other than the bacterium Streptomyces nodosus. The results presented in this thesis will be useful in the continuing search for novel bioactive compounds, the diagnosis of fungal infections, and as a source of insight into the interactions between microorganisms. Moreover, they show that even extensively studied fungal genera such as Aspergillus and Penicillium are not completely understood and may produce unexpected or previously unknown bioactive metabolites under appropriate conditions.

No description available.

Submitted by admin tede (tede@pucgoias.edu.br) on 2017-04-27T14:24:41Z No. of bitstreams: 1 DAIANE DE OLIVEIRA CUNHA.pdf: 2074632 bytes, checksum: 76e82c4169a9d294dcddcc8e9ad849cb (MD5) / Made available in DSpace on 2017-04-27T14:24:41Z (GMT). No. of bitstreams: 1 DAIANE DE OLIVEIRA CUNHA.pdf: 2074632 bytes, checksum: 76e82c4169a9d294dcddcc8e9ad849cb (MD5) Previous issue date: 2017-03-13 / The present dissertation was constructed in the form of scientific articles, being constituted by two articles. The first one, titled "Epidemiological evaluation of patients submitted to the serum galactomannan test with suspected Aspergillosis Invasive", aimed to evaluate the incidence of Invasive Aspergillosis in patients with hematological diseases followed at a reference hospital in Goiânia, Goiás, Brazil. Determine the main factors that contribute to the development of the disease. For this, 1367 samples of 264 patients with malignant hematological diseases treated in the Hematology Sector of Hospital Araújo Jorge, who underwent galactomannan detection, were evaluated in the period from 2013 to 2015, and were excluded patients who had no clinical data in Medical records and loss of follow-up at the hospital. Among the data obtained through the present study it was observed that the mean age was 43.7 years, where 55.5% were male. Of the total number of patients evaluated, 133 performed BMT, 38.9% of which were autologous and 17.9% of the allogeneic type. According to the classification for Invasive Aspergillosis according to the European Organization for Research and Treatment of Cancer, the disease was interpreted as proven in 7.3%, defined by culture positive for the fungus, 6.4% as probable by the detection of galactomannan in the Blood and presence of pulmonary infiltrates and 5.1% as possible by radiological alterations suggestive of Invasive Aspergillosis and galactomannan negative. The estimated / probable / probable Aspergillosis Invasive mortality rate was 61.3% and showed that the disease was significantly associated with the risk of death (p <0.0001). When considering the high mortality rate caused by the development of Aspergillosis Invasive and the fact that an early therapy promotes a significant improvement in the prognosis of patients, we conclude that the detection of galactomannan, performed as a follow-up of patients at high risk of developing the disease, can Be considered an effective method to aid in the identification of Invasive Aspergillosis. The second article entitled "Association between polymorphisms of genes encoding Dectin-1 and Toll-like cellular receptors and susceptibility to Invasive Aspergillosis", aimed to describe the polymorphisms in genes encoding Dectin-1 and Tolllike receptors, Seeking possible associations with the individual susceptibility to Invasive Aspergillosis. This study used as a methodological basis a systematic review of the literature and as a database to PubMed and PMC of the NCBI. The keywords used were: Invasive aspergillosis, polymorphism, Dectin-1 and Toll-like. From this search, 415 studies were found and according to the inclusion and exclusion criteria 8 studies were selected. With the accomplishment of this, it was verified that several are the studies that describe the single base polymorphisms with a greater susceptibility to the Invasive Aspergillosis. The major ones are in genes encoding Toll-like receptors and those that encode cytokines and chemokines (Dectin-1). Thus, it can be observed that, according to studies already carried out, there is a significant association of genetic polymorphisms with Aspergillosis Invasive, but more extensive studies must be performed to obtain more reliable results. In general, we conclude with this dissertation that the development of Invasive Aspergillosis is associated with several factors, one of them being genetic, and that, due to the high mortality rates caused by Invasive Aspergillosis, the detection of galactomannan is of fundamental importance for the Treatment of patients who are more likely to develop the disease, mainly aiding in the prognosis and early diagnosis of it. / A presente dissertação foi construída na modalidade de artigos científicos, sendo constituída por dois artigos. O primeiro, intitulado “Avaliação epidemiológica de pacientes submetidos ao teste de galactomanana sérica com suspeita de Aspergilose Invasiva”, teve como objetivo avaliar a incidência de Aspergilose Invasiva em pacientes com doenças hematológicas acompanhadas em um hospital de referência de Goiânia, Goiás, Brasil, e determinar os principais fatores que contribuem para o desenvolvimento da doença. Para isso, foram avaliadas 1367 amostras de 264 pacientes com doenças hematológicas malignas tratadas no Setor de Hematologia do Hospital Araújo Jorge, os quais realizaram exame de detecção de galactomanana, no período de 2013 a 2015, e foram excluídos pacientes que não possuíam dados clínicos em prontuários e com perda de seguimento no hospital. Dentre os dados alcançados por meio do presente estudo observou-se que a média de idade foi de 43,7 anos, onde 55,5% eram pertencentes ao sexo masculino. Do total de pacientes avaliados, 133 realizaram TMO, sendo que 38,9% eram do tipo autólogo e 17,9% do tipo alogênico. De acordo com a classificação para Aspergilose Invasiva conforme a European Organization for Research and Treatment of Cancer, a doença foi interpretada como comprovada em 7,3%, definida por cultura positiva para o fungo, 6,4% como provável pela detecção de galactomanana no sangue e presença de infiltrados pulmonares e 5,1% como possível por alterações radiológicas sugestivas de Aspergilose Invasiva e galactomanana negativo. A taxa de mortalidade para Aspergilose Invasiva comprovada/provável/possível foi de 61,3% e mostrou que a doença estava significativamente associada com o risco de morte (p<0,0001). Ao considerarmos a alta taxa de mortalidade causada pelo desenvolvimento da Aspergilose Invasiva e que a realização de uma terapia precoce promove significativa melhora do prognóstico dos pacientes, concluímos que a detecção de galactomanana, realizada como acompanhamento dos pacientes com alto risco de desenvolver a doença, pode ser considerada um método eficaz para auxiliar na identificação de Aspergilose Invasiva. O segundo artigo, intitulado “Associação entre polimorfismos dos genes que codificam os receptores celulares Dectina-1 e Toll-like e susceptibilidade à Aspergilose Invasiva”, teve como objetivo descrever os polimorfismos nos genes que codificam os receptores Dectina-1 e Toll-like, buscando possíveis associações com a susceptibilidade individual à Aspergilose Invasiva. Este estudo utilizou como base metodológica uma revisão sistemática da literatura e como base de dados a PubMed e PMC do NCBI. As palavras-chaves utilizadas foram: Invasive aspergillosis, polymorphism, Dectin-1 e Toll-like. A partir desta busca, 415 estudos foram encontrados e de acordo com os critérios de inclusão e exclusão 8 estudos foram selecionados. Com a realização deste, constatou-se que vários são os estudos que descrevem os polimorfismos de base única com uma maior susceptibilidade à Aspergilose Invasiva. Os principais são em genes que codificam os receptores Toll-like e os que codificam citocinas e quimiocinas (Dectina-1). Assim, pode-se perceber que de acordo com estudos já realizados há uma associação significativa de polimorfismos genéticos com a Aspergilose Invasiva, porém estudos mais amplos devem ser realizados para se obter resultados mais fidedignos. De modo geral, concluímos com essa dissertação que o desenvolvimento da Aspergilose Invasiva está associado com diversos fatores, sendo um deles o genético, e que, devido aos altos índices de mortalidade causados pela Aspergilose Invasiva, a detecção de galactomanana é de fundamental importância para o tratamento dos pacientes que apresentam uma maior probabilidade de desenvolver a doença, auxiliando principalmente no prognóstico e diagnóstico precoce da mesma.

Estudos recentes têm sugerido que doença pulmonar obstrutiva crônica (DPOC) possa ser um fator de risco para aspergilose invasiva (AI), particularmente no contexto de ventilação mecânica e uso de esteróides. Neste trabalho, realizamos estudo de coorte prospectivo multicêntrico (2009-2010) em três unidades de terapia intensiva no Sul do Brasil. Foram incluídos no estudo pacientes com DPOC que apresentassem novo infiltrado pulmonar enquanto em ventilação mecânica e sob uso de corticosteróides. Para estes pacientes, foram realizados os seguintes testes, em amostras respiratórias (maioria aspirado traqueal): exame micológico direto, cultura quantitativa para fungos, pesquisa de antígeno galactomanana (GM) (Platelia Aspergillus) e PCR em tempo real para Aspergillus. O DNA das amostras respiratórias foi extraído utilizando-se o kit de extração MycXtra (Myconostica, UK), sendo a amplificação feita com dois kits comerciais de q-PCR: Aspergillus spp q-PCR Alert kit (Nanogen, Itália) e MycAssayTM Aspergillus kit (Myconostica, UK). Foi também obtido soro destes pacientes, onde foi testada GM, precipitinas para Aspergillus e IgE total. O estudo foi aprovado no comitê de ética dos dois hospitais. Foram incluídos no estudo 47 pacientes (40,4% do sexo masculino), sendo a idade média de 68,6 anos (±9,9). A maioria (72,8%) dos pacientes possuía DPOC grave (GOLD III/IV). A dosagem de esteróides (equivalentes de prednisona) variou de 100-4125 mg (mediana: 900 mg). Exame micológico (direto e cultivo) foi positivo para Aspergillus seção Fumigatti em apenas dois pacientes (4,2%). Outros fungos identificados foram Scedosporium apiospermum (n=1) e Histoplasma capsulatum (n=1). Precipitinas para Aspergillus foram positivas em três pacientes, com títulos baixos (<1:2). Os níveis de IgE variaram de 2 a >3000 UI/ml (mediana de 74 UI/ml). Em sua grande maioria, os índices de GM no soro foram <0,5, enquanto que nas amostras respiratórias, os índices de GM foram >0,5, >1,0 e >1,5 em 74,5%, 40,5% e 21,3%, respectivamente. PCR da Myconostica foi positivo em 10 pacientes, enquanto PCR Nanogen detectou apenas um paciente. A mortalidade geral foi de 53,2%. Este estudo prospectivo multicêntrico mostrou uma baixa incidência (4,2%) de AI em pacientes com DPOC. A determinação de GM mostrou altos índices nas amostras analisadas (50% com índices ópticos >1,3), possivelmente necessitando um maior ponto de corte para excluir resultados falso-positivos. A combinação de PCR e GM para o diagnóstico de AI em amostras respiratórias merece investigação adicional, devido à baixa sensibilidade dos métodos de cultivo observados nos estudos clínicos realizados. / Recent data have suggested that chronic obstructive pulmonary disease (COPD) may be an important risk factor for invasive aspergillosis (IA), particularly in the context of mechanical ventilation (MV) and therapy with corticosteroids. Here we present the results of a prospective multicentric study (2009-2010) conducted in three intensive care units (ICUs) in Southern Brazil. COPD patients on steroids showing a new lung infiltrate while on mechanical ventilation were included and the following tests were performed in respiratory samples (mostly tracheal aspirates): microscopy, quantitative fungal culture, galactomannan (GM) (Platelia Aspergillus EIA) and real-time PCR to detect Aspergillus DNA. DNA was extracted using MycXtra kit (Myconostica, UK) and amplification was performed using two q-PCR commercial kits: Aspergillus spp q-PCR Alert kit (Nanogen, Italy) and MycAssayTM Aspergillus kit (Myconostica, UK). Serum was also obtained and tested for Aspergillus precipitins, GM and total IgE levels. Ethical approval was obtained in each of the participant hospitals. A total of 47 patients were enrolled in the study (male 59.6%). Mean age was 68.6 years-old (± 9.9). Most patients had severe COPD (GOLD stages III/IV in 72.8%). Steroid dosage (prednisone equivalent) ranged from 100-4125 mg (median 900 mg). Microscopy and culture were positive for Aspergillus section Fumigatti in only 2 patients (4.2%). Other fungi included H. capsulatum (n=1) and S. apiospermum (n=1). Aspergillus precipitins were positive for three patients, at low titers (<1:2). IgE levels ranged from 2 to >3,000 IU/ml (median 74 IU/ml). All serum GM indexes were <0.5 and respiratory samples, GM indexes of >0.5, >1.0 and >1.5 were observed in 74.5%, 40.5%, and 21.3%, respectively. Myconostica PCR was positive in 10 patients, while Nanogen PCR detected only one patient. Overall mortality was 53.2%. This prospective multicenter study showed a low incidence (4.2%) of IA in critically ill patients with COPD. High optical indices were observed when GM was tested in respiratory samples (50% of the results showed indices of >1.3). Therefore, the test did not discriminate IA and a a higher cutoff would be needed to exclude false-positive results. The combination of PCR and GM for the diagnosis of IA in respiratory samples deserves further investigation due to the low diagnostic sensitivity of the classical mycology methods.

Estudos recentes têm sugerido que doença pulmonar obstrutiva crônica (DPOC) possa ser um fator de risco para aspergilose invasiva (AI), particularmente no contexto de ventilação mecânica e uso de esteróides. Neste trabalho, realizamos estudo de coorte prospectivo multicêntrico (2009-2010) em três unidades de terapia intensiva no Sul do Brasil. Foram incluídos no estudo pacientes com DPOC que apresentassem novo infiltrado pulmonar enquanto em ventilação mecânica e sob uso de corticosteróides. Para estes pacientes, foram realizados os seguintes testes, em amostras respiratórias (maioria aspirado traqueal): exame micológico direto, cultura quantitativa para fungos, pesquisa de antígeno galactomanana (GM) (Platelia Aspergillus) e PCR em tempo real para Aspergillus. O DNA das amostras respiratórias foi extraído utilizando-se o kit de extração MycXtra (Myconostica, UK), sendo a amplificação feita com dois kits comerciais de q-PCR: Aspergillus spp q-PCR Alert kit (Nanogen, Itália) e MycAssayTM Aspergillus kit (Myconostica, UK). Foi também obtido soro destes pacientes, onde foi testada GM, precipitinas para Aspergillus e IgE total. O estudo foi aprovado no comitê de ética dos dois hospitais. Foram incluídos no estudo 47 pacientes (40,4% do sexo masculino), sendo a idade média de 68,6 anos (±9,9). A maioria (72,8%) dos pacientes possuía DPOC grave (GOLD III/IV). A dosagem de esteróides (equivalentes de prednisona) variou de 100-4125 mg (mediana: 900 mg). Exame micológico (direto e cultivo) foi positivo para Aspergillus seção Fumigatti em apenas dois pacientes (4,2%). Outros fungos identificados foram Scedosporium apiospermum (n=1) e Histoplasma capsulatum (n=1). Precipitinas para Aspergillus foram positivas em três pacientes, com títulos baixos (<1:2). Os níveis de IgE variaram de 2 a >3000 UI/ml (mediana de 74 UI/ml). Em sua grande maioria, os índices de GM no soro foram <0,5, enquanto que nas amostras respiratórias, os índices de GM foram >0,5, >1,0 e >1,5 em 74,5%, 40,5% e 21,3%, respectivamente. PCR da Myconostica foi positivo em 10 pacientes, enquanto PCR Nanogen detectou apenas um paciente. A mortalidade geral foi de 53,2%. Este estudo prospectivo multicêntrico mostrou uma baixa incidência (4,2%) de AI em pacientes com DPOC. A determinação de GM mostrou altos índices nas amostras analisadas (50% com índices ópticos >1,3), possivelmente necessitando um maior ponto de corte para excluir resultados falso-positivos. A combinação de PCR e GM para o diagnóstico de AI em amostras respiratórias merece investigação adicional, devido à baixa sensibilidade dos métodos de cultivo observados nos estudos clínicos realizados. / Recent data have suggested that chronic obstructive pulmonary disease (COPD) may be an important risk factor for invasive aspergillosis (IA), particularly in the context of mechanical ventilation (MV) and therapy with corticosteroids. Here we present the results of a prospective multicentric study (2009-2010) conducted in three intensive care units (ICUs) in Southern Brazil. COPD patients on steroids showing a new lung infiltrate while on mechanical ventilation were included and the following tests were performed in respiratory samples (mostly tracheal aspirates): microscopy, quantitative fungal culture, galactomannan (GM) (Platelia Aspergillus EIA) and real-time PCR to detect Aspergillus DNA. DNA was extracted using MycXtra kit (Myconostica, UK) and amplification was performed using two q-PCR commercial kits: Aspergillus spp q-PCR Alert kit (Nanogen, Italy) and MycAssayTM Aspergillus kit (Myconostica, UK). Serum was also obtained and tested for Aspergillus precipitins, GM and total IgE levels. Ethical approval was obtained in each of the participant hospitals. A total of 47 patients were enrolled in the study (male 59.6%). Mean age was 68.6 years-old (± 9.9). Most patients had severe COPD (GOLD stages III/IV in 72.8%). Steroid dosage (prednisone equivalent) ranged from 100-4125 mg (median 900 mg). Microscopy and culture were positive for Aspergillus section Fumigatti in only 2 patients (4.2%). Other fungi included H. capsulatum (n=1) and S. apiospermum (n=1). Aspergillus precipitins were positive for three patients, at low titers (<1:2). IgE levels ranged from 2 to >3,000 IU/ml (median 74 IU/ml). All serum GM indexes were <0.5 and respiratory samples, GM indexes of >0.5, >1.0 and >1.5 were observed in 74.5%, 40.5%, and 21.3%, respectively. Myconostica PCR was positive in 10 patients, while Nanogen PCR detected only one patient. Overall mortality was 53.2%. This prospective multicenter study showed a low incidence (4.2%) of IA in critically ill patients with COPD. High optical indices were observed when GM was tested in respiratory samples (50% of the results showed indices of >1.3). Therefore, the test did not discriminate IA and a a higher cutoff would be needed to exclude false-positive results. The combination of PCR and GM for the diagnosis of IA in respiratory samples deserves further investigation due to the low diagnostic sensitivity of the classical mycology methods.

Estudos recentes têm sugerido que doença pulmonar obstrutiva crônica (DPOC) possa ser um fator de risco para aspergilose invasiva (AI), particularmente no contexto de ventilação mecânica e uso de esteróides. Neste trabalho, realizamos estudo de coorte prospectivo multicêntrico (2009-2010) em três unidades de terapia intensiva no Sul do Brasil. Foram incluídos no estudo pacientes com DPOC que apresentassem novo infiltrado pulmonar enquanto em ventilação mecânica e sob uso de corticosteróides. Para estes pacientes, foram realizados os seguintes testes, em amostras respiratórias (maioria aspirado traqueal): exame micológico direto, cultura quantitativa para fungos, pesquisa de antígeno galactomanana (GM) (Platelia Aspergillus) e PCR em tempo real para Aspergillus. O DNA das amostras respiratórias foi extraído utilizando-se o kit de extração MycXtra (Myconostica, UK), sendo a amplificação feita com dois kits comerciais de q-PCR: Aspergillus spp q-PCR Alert kit (Nanogen, Itália) e MycAssayTM Aspergillus kit (Myconostica, UK). Foi também obtido soro destes pacientes, onde foi testada GM, precipitinas para Aspergillus e IgE total. O estudo foi aprovado no comitê de ética dos dois hospitais. Foram incluídos no estudo 47 pacientes (40,4% do sexo masculino), sendo a idade média de 68,6 anos (±9,9). A maioria (72,8%) dos pacientes possuía DPOC grave (GOLD III/IV). A dosagem de esteróides (equivalentes de prednisona) variou de 100-4125 mg (mediana: 900 mg). Exame micológico (direto e cultivo) foi positivo para Aspergillus seção Fumigatti em apenas dois pacientes (4,2%). Outros fungos identificados foram Scedosporium apiospermum (n=1) e Histoplasma capsulatum (n=1). Precipitinas para Aspergillus foram positivas em três pacientes, com títulos baixos (<1:2). Os níveis de IgE variaram de 2 a >3000 UI/ml (mediana de 74 UI/ml). Em sua grande maioria, os índices de GM no soro foram <0,5, enquanto que nas amostras respiratórias, os índices de GM foram >0,5, >1,0 e >1,5 em 74,5%, 40,5% e 21,3%, respectivamente. PCR da Myconostica foi positivo em 10 pacientes, enquanto PCR Nanogen detectou apenas um paciente. A mortalidade geral foi de 53,2%. Este estudo prospectivo multicêntrico mostrou uma baixa incidência (4,2%) de AI em pacientes com DPOC. A determinação de GM mostrou altos índices nas amostras analisadas (50% com índices ópticos >1,3), possivelmente necessitando um maior ponto de corte para excluir resultados falso-positivos. A combinação de PCR e GM para o diagnóstico de AI em amostras respiratórias merece investigação adicional, devido à baixa sensibilidade dos métodos de cultivo observados nos estudos clínicos realizados. / Recent data have suggested that chronic obstructive pulmonary disease (COPD) may be an important risk factor for invasive aspergillosis (IA), particularly in the context of mechanical ventilation (MV) and therapy with corticosteroids. Here we present the results of a prospective multicentric study (2009-2010) conducted in three intensive care units (ICUs) in Southern Brazil. COPD patients on steroids showing a new lung infiltrate while on mechanical ventilation were included and the following tests were performed in respiratory samples (mostly tracheal aspirates): microscopy, quantitative fungal culture, galactomannan (GM) (Platelia Aspergillus EIA) and real-time PCR to detect Aspergillus DNA. DNA was extracted using MycXtra kit (Myconostica, UK) and amplification was performed using two q-PCR commercial kits: Aspergillus spp q-PCR Alert kit (Nanogen, Italy) and MycAssayTM Aspergillus kit (Myconostica, UK). Serum was also obtained and tested for Aspergillus precipitins, GM and total IgE levels. Ethical approval was obtained in each of the participant hospitals. A total of 47 patients were enrolled in the study (male 59.6%). Mean age was 68.6 years-old (± 9.9). Most patients had severe COPD (GOLD stages III/IV in 72.8%). Steroid dosage (prednisone equivalent) ranged from 100-4125 mg (median 900 mg). Microscopy and culture were positive for Aspergillus section Fumigatti in only 2 patients (4.2%). Other fungi included H. capsulatum (n=1) and S. apiospermum (n=1). Aspergillus precipitins were positive for three patients, at low titers (<1:2). IgE levels ranged from 2 to >3,000 IU/ml (median 74 IU/ml). All serum GM indexes were <0.5 and respiratory samples, GM indexes of >0.5, >1.0 and >1.5 were observed in 74.5%, 40.5%, and 21.3%, respectively. Myconostica PCR was positive in 10 patients, while Nanogen PCR detected only one patient. Overall mortality was 53.2%. This prospective multicenter study showed a low incidence (4.2%) of IA in critically ill patients with COPD. High optical indices were observed when GM was tested in respiratory samples (50% of the results showed indices of >1.3). Therefore, the test did not discriminate IA and a a higher cutoff would be needed to exclude false-positive results. The combination of PCR and GM for the diagnosis of IA in respiratory samples deserves further investigation due to the low diagnostic sensitivity of the classical mycology methods.

Lors de travaux, la mise en suspension des spores d’Aspergillus constitue un facteur de risque reconnu dans le développement d’une aspergillose invasive. Durant l’année 2015, un pavillon de 6000 m2 (60 lits) de notre établissement a été entièrement déconstruit. L’objectif principal de cette étude a été d’évaluer l’association entre la concentration des spores d’Aspergillus fumigatus (AF) dans l’environnement extérieur et intérieur des pavillons, mais également avec la coexistence de cas cliniques, afin de proposer des recommandations d’amélioration (pratiques & techniques). Pour cela, durant 11 mois, une surveillance prospective de la contamination à Aspergillus fumigatus (AF) de l’air extérieur et intérieur par impaction sur gélose, mais aussi une investigation épidémiologique des patients à risque ont été mis en place. Au total, 3885 prélèvements d’air ont été réalisés (1744 extérieurs et 2141 intérieurs) permettant, par calcul des ratios de contamination (extérieurs vs intérieurs), de confirmer une efficacité des mesures de précautions pour réduire l’aérocontamination. Des prélèvements extérieurs continus des spores d’Aspergillacées (spore/m3/jour) ont également été réalisés par un capteur Hirst. Ce capteur, mais aussi le suivi des conditions météorologiques se sont révélés être des systèmes d’alerte utiles pour prévenir les pics de contamination. Enfin, 394 (383 environnementaux, 11 cliniques) isolats d’AF sensibles aux antifongiques ont été génotypés (MLVA). L’analyse des génotypes a montré 7 génotypes similaires entre des isolats d’AF cliniques et environnementaux confirmant un rôle de l’environnement hospitalier dans l’infection ou la colonisation des patients / Invasive aspergillosis (IA) due to Aspergillus has been associated with building construction, which may increase spores emission nearby immunocompromised patients. In 2015, one blocks of 6,000 m2 (60 beds) form our hospital has been entirely demolished. The aim of this study was to evaluate possible association between concentration of A. fumigatus (AF) spores in the outdoor and indoor environment and also with the clinical cases in order to propose some improvements in actuals methods and practices. A daily surveillance of fungal contamination was implemented during 11-months. Environmental survey was realized by air samplings, outdoor and indoor, with an automatic agar sampler. In parallel, surveillance of IA infection cases was conducted by epidemiological investigation. A total of 3885 air samples (1744 outdoor samples and 2141 indoor samples) were collected, allowing calculation of ratios (outdoor vs indoor) to confirm efficacy of preventives measures applied to reduce indoor aerocontamination. Outdoor continuous sampling of Aspergillaceae spores (spore/m3/day) was also realized by a Hirst collector. This collector was useful as alarm system to detect contamination peaks. Similarly, monitoring of meteorological parameters seems to be an interesting tool, to prevent Aspergillus peaks. Finally, 394 isolates of AF, susceptible to antifungals (383 environmental and 11 clinical isolates) were genotyped using MLVA. Analysis of genotypes showed 7 similar genotypes shared by environmental and clinical isolates, suggesting that clinical colonization and/or infection may originate from the hospital environment

Depuis la disponibilité des combinaisons antirétrovirales (cART) en 1996, l’incidence des infections opportunistes classantes SIDA (IO), dont la pneumocystose (PCP) a très fortement diminué. Malgré tout, chez les patients infectés par le VIH, la PCP était la 2ème IO la + fréquente en France en 2001-2003 et les infections fongiques, avec 1 million de nouveaux cas/an de cryptococcose, restent un problème de santé publique majeur au niveau mondial. Cependant, depuis l’ère des cART, très peu de recherches épidémiologiques sur les infections fongiques dans les pays industrialisés ont été entreprises. C’est dans ce contexte que nous avons mené une étude épidémiologique de 2 infections fongiques chez les patients infectés par le VIH en France sur la French Hospital Database on HIV ANRS CO4 (FHDH) : la pneumocystose et l’aspergillose invasive. Concernant la pneumocystose, sur la période 2004-2011, dans la base FHDH, la moitié des 1259 cas de PCP étaient survenus chez des patients qui avaient interrompus leur suivi, et, pour ceux qui avaient déjà eu une IO avant la PCP, leur mortalité était de 25% à 3 ans. Pour l’aspergillose invasive (AI), après un retour national aux dossiers des cas déclarés sur 20 ans sur la base FHDH, un comité d’experts a validé 242 cas d’AI. Les données montrent que, chez les patients infectés par le VIH, seulement la moitié des AI validées répondaient aux critères EORTC. La mortalité à 3 mois après une AI s’est améliorée après l’ère des cART et un rôle protecteur du voriconazole sur la survie à 3 mois a également été démontré pour la 1ère fois chez les patients infectés par le VIH. / The advent of combined antiretroviral therapy (cART) in 1996 resulted in a dramatic fall in the incidence of AIDS-defining illness (ADI), including Pneumocystis jirovecii pneumonia (PCP). Nevertheless, PCP was the second most frequent ADI in France in 2001-2003 and fungal infections remain a major threat for HIV-infected individuals worldwide. Epidemiological data on fungal infections in the late cART period in resource-rich settings are scarce. The purpose of our work was to study changes in the epidemiology of fungal infections among HIV-infected individuals in France in the late cART period, focusing on PCP and invasive aspergillosis (IA) in the French Hospital Database on HIV ANRS CO4 (FHDH). In the FHDH, during the 2004-2011 period, half of the 1259 PCP cases occurred among HIV-infected individuals who had waning adherence to care, and for those who had a prior ADI before PCP the 3-year mortality rate was 25%. For the second study on IA, a review committee validated IA cases among all the cases that included a diagnostic code for aspergillosis (ICD-9 or ICD-10) in the FHDH over a 20-year period. Our study demonstrated that only half of validated IA cases among HIV-infected individuals met EORTC criteria. The 3-months survival rate after IA diagnosis improved after the advent of cART and a protective role of voriconazole was observed in the period after 2001.

Among the different pulmonary fungal infections, aspergillosis, and in particular invasive pulmonary aspergillosis (IPA), are becoming the most worrying diseases in immunocompromised patients. This is due to their high incidence and mortality. Indeed, invasive aspergillosis manifests as invasive pulmonary disease accounting for 50/60% of all cases, with a mortality of 50-90% in severely immunocompromised patients. Triazoles act by inhibiting 14-α demethylase, a fungal cytochrome P450 enzyme implicated in the synthesis of ergosterol, an essential constituent of fungal cell walls. Moreover, they interact with the same cytochrome present in large quantities in the human liver, inducing possible drug-drug interactions in IPA patients. Consequently, interactions resulting from inhibitors, inductors, or substrates of cytochromes can modify the plasmatic concentrations of triazoles or other drugs administered concomitantly. To overcome these important issues, pulmonary delivery of triazoles could be an interesting alternative to conventional routes.The aim of this work was to develop triazole-based dry powders for inhalation able to be deposited adequately in the lungs, with a release of drug and a lung retention that can optimize its pharmacological action. This work focused on two active pharmaceutical ingredients (API): itraconazole (ITZ), for which improved solubility was needed, and voriconazole (VCZ), for which slow release was required.Concerning ITZ, solid dispersions for inhalation (SDIs) comprising ITZ and mannitol were previously developed in our laboratory. The selected SDI showed interesting results in terms of improved dissolution and lung retention in vivo in mice during a pharmacokinetic study. Therefore, this SDI was tested in a murine preclinical model of IPA and showed promising results in terms of prophylaxis efficacy. One aim of this work was to continue the pharmaceutical development of this promising SDI by making a scaling-up study. These methods were intended to improve the SDI’s ecological footprint and productivity by increasing the production yield and decreasing the amount of solvents and time used in its manufacture. During the first step of this study, the obtained SDI showed interesting results obtaining similar powder characteristics (i.e. amorphous content, aerodynamic performance, and dissolution profiles) from concentrated solutions using a laboratory-scale spray-dryer B-290 (Büchi, Switzerland) before using a pilot-scale spray-dryer (GEA Niro, Denmark). Then, the upscaling was performed on the pilot spray-dryer allowing the production of SDIs with increased productivity (yield and process duration). These SDIs had similar powder characteristics than the optimized lab-scale SDIs. During the second part of this work we developed VCZ based dry powder for inhalation. The aim was to slow down the release of this highly permeable and very slightly soluble API and to prolong its lung residence. To this end, various lipidic excipients were chosen. The selection took into account the potential good pulmonary tolerance of the lipids and their hydrophobicity to evaluate their ability to slow down the VCZ release (FPFs 20-25%, slowed release up to 24h, burst effect of ± 58% of VCZ dissolved within 30min). Immediate-release SDIs were also developed to have a comparator reference for the pharmacokinetic and efficacy studies (FPFs of 40%).Then, a pharmacokinetic study in mice was performed following the pulmonary administration of one immediate-release and two sustained-release SDIs (with or without PEG excipient). With an 80-fold higher pulmonary exposure over 24 hours, the slow-release SDIs presented a real interest compared to the immediate-release SDI. Moreover, in accordance with these results, VCZ plasma exposure following the administration of the SDI with PL90-H was more than 1.5-fold higher than its pulmonary exposure (AUC0-24 of 8.70 µg.h/g in the lungs and 14.70 µg.h/mL in the plasma). The slow-release formulations presented plasma exposures at least 15 times lower than their pulmonary exposures (AUC0-24 in lung of 741.40 and 686.85 µg.h/g vs plasmatic AUC0-24 of 37.44 and 42.81 µg.h.mL, respectively with and without PEG excipient). Moreover, the presence of PEG excipient did not influence the residence time and the exposure of the VCZ within the lungs. Finally, the sustained-release SDIs administration by inhalation led to VCZ lung and plasma concentrations higher than the minimal inhibitory concentration (MIC) of VCZ against Aspergillus fumigatus (1 μg/mL) over 24 h. Finally, a murine model of IPA was developed in our lab. The immunosuppression model was fixed and performed by the intraperitoneal (IP) injection of corticosteroids to induce a neutropenia state. Then, different doses of spores (from 1.10^4 to 5.10^6 spores) were inoculated to the neutropenic mice via an endotracheal instillation and the survival rate of each group was observed. Unfortunately, the survival rate resulting from the different infections were not reproducible. Therefore, these models were not suitable to conduct the efficacy study. This underlined the link between the immunosuppressive model and the infection. Indeed, the IPA murine model should be developed according to the immune state of the animal, the Aspergillus conidia species and its concentration to be used. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished

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