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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.
421

Stress and psychosocial adjustment among people living with HIV/AIDS in China. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Conclusions The results showed that depression is prevalent among Chinese PLWH and perceived discrimination is a source of stress. Perceived stress, social support and coping strategies had independent effects on mental health outcomes but there were no interaction effects. The Brief COPE was validated and had a structure different from the original, again supporting the importance of cultural variations. Our results hence provided useful instrumentations (PSSHIV and Brief COPE) as well as a good foundation for the development of theories and interventions specific to the needs of the PLWH in China. / Introduction Mental health issues are prevalent among People Living with HIV (PLWH). Instrumentation, conceptualization and theoretical models of stress-coping-mental health relationships among PLWH are important but theoretical and practical differences exist in the context of different cultures and quality of care services. / Objectives The aims of the study were 1) to develop a new Perceived Stress Scale for People Living with HIV (PSSHIV); 2) to validate the Brief COPE inventory among Chinese PLWH; 3) to investigate determinants of perceived stress and psychological well-being. / Results The newly developed PSSHIV and the rearranged version of the Brief COPE were validated and found to have acceptable psychometric properties. Of all participants, 63.3% showed moderate/severe depressive symptoms. 'Problem-solving and Acceptance' and 'Self-blame and Denial' were commonly used coping strategies. Socioeconomic status (SES), perceived discrimination, and optimism were significantly associated with overall stress and some of the subscales of PSSHIV. Perceived stress appeared to mediate the relationship between perceived discrimination and psychological well-being. In addition to perceived stress, social support and some particular coping strategies were associated with depression. Similar though not identical results were found using quality of life as the outcome. / Subject and Methods To achieve Aim 1, PLWH in two Chinese cities were interviewed for item generation and validation. Aims 2 to 4 were achieved through another survey conducted in the same cities. Participants were recruited from the registry of the Centers for Disease Control and Prevention and from users of hospital services and Methadone Maintenance Treatment clinics. Standard statistical methods were used for validation studies. / Su, Xiaoyou. / Adviser: Tak Fai Joseph Lau. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 181-206). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
422

制度的神話: NGO推行男男性接觸者預防愛滋病措施的研究. / Zhi du de shen hua: NGO tui xing nan nan xing jie chu zhe yu fang ai zi bing cuo shi de yan jiu.

January 2008 (has links)
吳木欣. / "2008年7月". / "2008 nian 7 yue". / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 169-174). / Abstracts in Chinese and English. / Wu Muxin. / 目錄 / 引言 --- p.9 / Chapter 第一章 --- 文獻回顧 / Chapter 1 --- 何謂 MSM? --- p.11 / Chapter 2 --- 回顧亞洲男男性接觸者感染愛滋病之情況 --- p.11 / Chapter 3 --- 愛滋病感染率急升之原因 --- p.14 / Chapter 3.1 --- 香港同性戀者情況 --- p.17 / Chapter 4 --- 各地政府和NGOs之回應 --- p.19 / Chapter ■ --- 歧視與愛滋病的關連 --- p.20 / Chapter 4.1 --- 美國經驗´ؤ´ؤ活動取向之多元 --- p.21 / Chapter 4.2 --- 亞洲經驗一政府的不支持,非政府組織的無力 --- p.23 / Chapter 5 --- 回顧政府和香港非政府組織(NGOs)的角色 --- p.24 / Chapter 5.1 --- 香港政府採取的措施 --- p.24 / Chapter 5.1.1 --- ACA的建議政策角色 --- p.26 / Chapter 5.1.2 --- ATF的撥款機制角色 --- p.28 / Chapter 5.1.3 --- 非政府組織的工作 --- p.35 / Chapter 6 --- 是次研究的分析框架和概念 --- p.38 / Chapter 7 --- 研究重要之處 --- p.45 / Chapter 第二章 --- 研究方法 --- p.47 / Chapter 第三章 --- 誰是決策者 --- p.52 / Chapter 第四章 --- 主流組織的失敗一一反思一筆過撥款的弊端 --- p.73 / Chapter 第五章 --- 愛滋病非政府組織的無力 --- p.94 / Chapter 第六章 --- 草根組織的掙扎求存 --- p.103 / Chapter 第七章 --- 政府的割裂 --- p.115 / Chapter 第八章 --- 非政府組織的工作---愛滋病只是愛滋病嗎? --- p.130 / Chapter 第九章 --- 總結 --- p.158 / 參考文獻 --- p.169 / 附件一 --- p.175 / 附件二 --- p.176
423

Myocardial Macrophage Phenotypic Variation and Cytokine-Mediated Induction of HIV-Associated Cardiac Disease: A Dissertation

Yearley, Jennifer Holmes 20 March 2008 (has links)
Ventricular dysfunction and dilated cardiomyopathy (DCM) develop among untreated HIV-infected people at much higher rates than among HIV-negative individuals, resulting in significant contributions to morbidity and mortality. Mechanisms underlying development of HIV-associated cardiomyopathy (HIVCM) are as yet poorly understood. The well-characterized simian immunodeficiency virus (SIV) model of HIV infection provides a unique context for HIVCM pathogenesis studies in that SIV-infected rhesus monkeys develop myocardial lesions and contractile dysfunction similar to those described in HIV-infected people, suggesting a shared disease mechanism. Lymphocytic myocarditis is a commonly reported finding in AIDS patients at autopsy and constitutes one of several conditions known to predispose to development of DCM, irrespective of HIV-infection status. As lymphocytic myocarditis also occurs with high frequency among SIV-infected rhesus monkeys, a retrospective analysis of rhesus monkey cardiac tissue collected at necropsy was performed to examine viral and cellular correlates of lymphocytic inflammation within myocardial tissue. One subpopulation of macrophages, which has been reported by other groups to be associated with an anti-inflammatory phenotype, was found to correlate inversely with lymphocytic infiltration and positively with numbers of virus infected cells, suggesting effects of an anti-inflammatory cytokine production profile. In contrast, the detrimental effects of inflammatory cytokines on myocardial structure and function are well-recognized and HIV infection in general is characterized by chronic immune activation and inflammatory cytokine dysregulation. To further investigate a role for myocardial cytokine production in development of HIVCM, a prospective study was conducted in which SIV-infected rhesus monkeys and uninfected controls were treated with recurrent administration of inactivated Mycobacterium aviumcomplex bacteria (MAC). SIV-infected, MAC-treated animals rapidly developed significant ventricular systolic dysfunction and chamber dilatation not seen in control groups, suggesting an exaggerated myocardial sensitivity to exogenous antigenic stimulation. Concurrent treatment with the TNFα antagonist etanercept completely abrogated development of these changes, strongly implicating a causative role for TNFα in evolution of the contractile dysfunction and chamber remodeling. Findings reported from the current studies suggest that characteristics of local myocardial macrophage populations and the myocardial tissue cytokine milieu may play more important roles than lymphocytic infiltration, cardiomyocyte damage, or viral proteins in the pathogenesis of HIVCM.
424

Étude de faisabilité d'un système de détection automatique des patients à risque épidémique à partir des données du dossier médical informatisé des urgences / Evaluation of an automatic detection system of patients with potentially transmissible infectious disease from emergency department computerized record

Gerbier-Colomban, Solweig 21 December 2012 (has links)
Introduction. La détection précoce des infections par un système de surveillance efficace permet de mettre en œuvre des mesures de prévention et de contrôle adaptées. L’objectif de cette thèse était d’évaluer les performances d’un système de détection automatique, type syndromique, des patients à risque épidémique à partir des données du dossier médical informatisé des urgences. Population d’étude. 101001 patients ayant consulté aux urgences du groupement Nord des Hospices Civils de Lyon, entre le 01/06/2007 et le 31/03/2011, dont 10895 patients hospitalisés dans l’établissement à l’issue de la consultation. Méthode. Trois étapes ont été nécessaires. 1) Évaluation de la faisabilité d’utiliser les données structurées et textuelles, à l’aide d’une application de traitement automatisé des données textuelles. 2) Construction et évaluation d’algorithmes de repérage, pour les syndromes respiratoire, cutané et gastro-intestinal, de patients avec une infection à risque épidémique à partir des données du dossier médical informatisé des urgences. 3) Évaluation des données du dossier médical des urgences pour la détection d’épidémies communautaires de grippe, comparées aux données régionales de surveillance de la grippe. Résultats et Discussion. Cette thèse a montré que qu’il est possible de repérer des patients à risque épidémique avec une balance raisonnable entre la sensibilité et la spécificité pour des syndromes respiratoires et cutanés. Les algorithmes pour des syndromes gastro-intestinaux n'étaient pas assez spécifiques pour une utilisation de routine. Les données d’urgences ont permis aussi de détecter les épidémies communautaires dès le début de l’épidémie locale / Introduction. The early detection of the infections by an effective surveillance system allows implementing adapted measures of prevention and control. The objective of this thesis was to estimate the performances of an automatic system syndromic-like to detect the patients with potentially transmissible infectious diseases from the emergency department computerized medical record data. Study population. 101,001 adults, who were admitted to the emergency department and hospitalised of the North Hospital In University Hospital of Lyon, between 01/06/2007 and 30/03/2011. Method. Three steps were necessary. 1) Evaluation of the feasibility to use the structured and textual data with an application which automatically extracts and encodes information found in narrative reports. 2) Different algorithms were built for the detection of patients with infectious respiratory, cutaneous or gastrointestinal syndromes, and assessed. 3) Evaluation of the data of the electronic medical record of emergency department for the detection of flu community epidemics, compared with regional surveillance networks for flu. Results and discussion. This thesis showed that it is possible to detect patients with potentially transmissible infectious diseases with reasonable balance between sensitivity and specificity for respiratory and cutaneous syndromes. The algorithms for gastrointestinal syndromes were not specific enough for their routine use. Emergency department data enabled the detection of community outbreaks for flu
425

Be here now : evaluating an adapted mindfulness-based intervention in a mixed population with acquired brain injury (ABI) and neurological conditions

Canadé, Rosario Franco January 2014 (has links)
Acquired brain injury (ABI) and long-term neurological conditions (such as multiple sclerosis, Parkinson’s disease), are major causes of disability in the UK, and can lead to significant physical, cognitive, neuro-behavioural, psychological and social difficulties for sufferers. Individuals affected by an ABI or neurological conditions commonly report difficulties around emotional adjustment, reduced attention, mental control, and self-efficacy and their health-related quality of life also often appears to be much reduced. Whilst conventional neuro-rehabilitation has tended to address physical and cognitive impairments and deficits rather than psychological sequelae, recently a growing trend for more holistic approaches appears to have emerged (e.g., Wilson et al., 2000, 2013). Amongst these approaches, mindfulness-based interventions (collectively known as MBIs) have sought to address this gap in terms of therapeutic intervention. There is a growing body of research evidence pointing to the utility of MBIs in the rehabilitation and support of these populations in improving perceived quality of life and increasing self-management of these conditions. However, the research still remains limited and debate persists in terms of the conceptual and theoretical framework of mindfulness. The present study sought to evaluate the effectiveness of an adapted, short-form MBI group programme for a mixed population of patients (n = 22) currently offered in a local neuro-rehabilitation service. A specific pre-post control group design was adopted in order to investigate whether the intervention produced improvements in mindfulness skills, and whether these would in turn lead to improvements in measures associated with self-efficacy and perceived quality of life. Results indicated participants completing the MBI group programme showed significantly higher mean scores across measures of mindfulness. The results also indicated that these improvements were predictive of improvements across self-efficacy and quality of life measures, with large effect sizes observed. The findings would appear to support the research hypothesis that a suitably modified MBI is beneficial for a mixed ABI population. Findings, study limitations, clinical relevance and implications, as well as methodological and theoretical considerations and directions for future research are discussed in light of the main research questions.
426

Molecular and Biochemical Signaling Underlying Arabidopsis-Bacterial/Virus/Fungal Interactions

El-Shetehy, Mohamed H. 01 January 2016 (has links)
Systemic acquired resistance (SAR) is a form of inducible defense response triggered upon localized infection that confers broad-spectrum disease resistance against secondary infections. Several factors are known to regulate SAR and these include phenolic phytohormone salicylic acid (SA), phosphorylated sugar glycerol-3-phosphate (G3P), and dicarboxylic acid azelaic acid (AzA). This study evaluated a role for free radicals nitric oxide (NO) and reactive oxygen species (ROS) in SAR. Normal accumulation of both NO and ROS was required for normal SAR and mutations preventing NO/ROS accumulation and/or biosynthesis compromised SAR. A role for NO and ROS was further established using pharmacological approaches. Notably, both NO and ROS conferred SAR in a concentration dependent manner. This was further established using genetic mutants that accumulated high levels of NO. NO/ROS acted upstream of G3P and in parallel to SA. Collectively, these results suggest that NO and ROS are essential components of the SAR pathway.
427

Semantic memory impairments in schizophrenia : a neuropsychological study to evaluate competing theories

Doughty, Olivia January 2008 (has links)
People with a diagnosis of schizophrenia have been found to perform poorly on tasks assessing semantic memory, and these impairments have been proposed to be related to certain symptoms, in particular Formal Thought Disorder (FTD). A systematic literature review and meta-analysis identified the need a) to determine whether semantic memory is a primary impairment in schizophrenia and not secondary to other cognitive impairments and b) what cognitive models could provide the best explanation for the impairment. With these aims, Studies One and Two compared the performance of a group of people with schizophrenia across a battery of semantic memory tests (Hodges, Salmon and Butters, 1992). In order to eliminate confounding variables, two clinical control groups were recruited for comparison, one with a probable degraded semantic memory arising from Alzheimer‘s Dementia (AD) and the other with a primary dysexecutive syndrome caused by acquired brain injury (ABI). From these comparisons, it was possible to profile the semantic memory impairment in schizophrenia with the conclusion that any deficits are task-specific. Unlike the AD group, the impairment did not seem to arise from a loss of stored knowledge but nor did a retrieval problem, in its simplest terms, offer the best explanation. Since the ABI group performed normally on the battery it is clear that a dysexecutive syndrome does not necessarily explain poor semantic memory performance. Qualitatively, the associations and categories formed by people with schizophrenia on tasks of semantic categorisation e.g. the Category Generation Test (CGT) (Green, Done, Anthony, McKenna and Ochocki, 2004) often resemble loosening of associations and psychotic speech. In order to understand more about the processes involved in the formation of these bizarre categories, I compared performance on the CGT of groups of people with schizophrenia, AD and ABI. I found that the people with AD performed fairly similarly to the people with schizophrenia in that they sorted cards in an idiosyncratic way but the ABI group performed normally, adhering to taxonomic categories. Although this result might suggest that the bizarre associations on the CGT in people with schizophrenia are caused by a deficit in semantic memory (and not a dysexecutive syndrome), further analysis found important differences between the AD and the schizophrenia group in the way the card sorts were formed. In addition, both these groups showed intact semantic memory knowledge of the items they mis-sorted, indicating that categorisation problems do not necessarily arise from a degraded memory store. The difficulties people with schizophrenia appear to have on tests of associations and categorisation (e.g. CGT) could arise from a disorganised semantic memory i.e. differences in the way in which concepts are interconnected. On the CGT, patients with schizophrenia were far more likely to sort items on the basis of thematic (situational) information suggesting a preference for thematic over taxonomic associations. To test this, participants were tested using a triadic comparison task which requires choosing whether an item is best associated with a taxonomic, thematic or perceptually related item. On this test patients performed comparably to controls suggesting that their semantic memory is organised normally and that the abnormalities in the way in which items are associated on some semantic memory tests, including the CGT, are task-specific. It has been proposed that one of the core problems in schizophrenia is that there is ―an aberrant assignment of salience‖ (Kapur 2003) to contextually inappropriate concepts due to a dysregulated dopamine system (Kapur 2003; Kapur et al 2005). It is possible that this could also explain the semantic memory impairments in schizophrenia i.e. certain less relevant concepts/ associations are chosen because they are experienced as more salient. To test this, a group of patients with schizophrenia were assessed using a test of semantic salience. Compared to controls, the patients made significantly more errors of salience including significantly more errors where large aberrant attributions of importance were given to items. The tendency to make errors on the salience test was highly correlated with errors on the CGT and also the semantic association tests, indicating a common underlying mechanism. Therefore, it can be concluded that the semantic memory impairments in schizophrenia are task-specific, not caused by a loss of semantic knowledge or a dysexecutive syndrome, but due to an aberrant assignment of salience to less relevant semantic concepts. More work is needed to understand the cognitive processes underlying this aberrant attribution process, and also the biological substrates involved.
428

Global changes in Brassica napus gene activity in response to Sclerotinia sclerotiorum and the biocontrol agent Pseudomonas chlororaphis PA23

Duke, Kelly 15 September 2016 (has links)
The biological control agent Pseudomonas chlororaphis PA23 is effective at protecting Brassica napus (canola) from the necrotrophic fungus Sclerotinia sclerotiorum via direct antagonism. Despite the growing importance of biocontrol bacteria in protecting crop plants from fungal pathogens, little is known about how the host plant responds to bacterial priming on the leaf surface and certainly nothing about global changes in gene activity in the presence and absence of S. sclerotiorum. PA23 priming of mature canola plants reduced the number of lesion-forming petals by 90%. Global RNA sequencing of canola tissue at the host-pathogen interface showed a 16-fold reduction in the number of genes uniquely upregulated in response to S. sclerotiorum when pretreated with PA23. Upstream defense-related gene patterns suggest MAMP-triggered immunity via surface receptors detecting PA23 flagellin and peptidoglycans. Although systemic acquired resistance (SAR) was induced in all treatment groups, a response centered around a glycerol-3-phosphate (G3P)-mediated pathway was exclusively observed in canola plants treated with PA23 alone. Activation of these defense mechanisms by PA23 involved production of reactive oxygen species as well as pronounced thylakoid membrane structures and plastoglobule formation in leaf chloroplasts. PA23 therefore primes defense responses in the plant through the induction of unique local and systemic regulatory networks. / October 2016
429

Využití prostředků informačních technologií v hodinách hudební výchovy / Use of the information technology in the lessons of music education

Vosyková, Petra January 2012 (has links)
Thesis, entitled Use of the information technology in the lessons of music education aims to compare different approaches to teaching music education in high school, specifically to compare the form of traditional teaching with teaching by using an interactive whiteboard, in terms of their influence on memorization of curriculum. To verify the hypothesis implied that the use of interactive whiteboards in the lessons of music education has a positive impact on the level of acquired student's knowledge, I have created materials for lessons. These include both teaching material (supplied on CDROM), and verification tests, which enabled us to compare the results of the control groups of students. The analysis of the obtained results confirmed the expected hypothesis; difference between the control groups emerged, however, was not large enough to be able to clearly demonstrate that better results were caused by the use of interactive whiteboards in the classroom. Positive contribution of interactive whiteboard reflected greater involvement of students in the lessons and proactive approach to the studied topics, which in turn positively influenced the level of their acquired knowledge.
430

Recherche de nouveaux agents pathogènes associés aux pneumopathies nosocomiales

Bousbia, Sabri 29 September 2011 (has links)
Récemment, les microbiotes pulmonaires bactériens d’un nombre très limité de patients atteints de mucoviscidose et de pneumopathies acquises sous ventilation mécanique (PAVM) ont été étudiés en utilisant l'amplification du gène 16S rDNA bactérien suivie par la construction de librairies de clones et différentes approches de séquençage. Ces études ont montré que la population microbienne de patients atteints de maladies respiratoires était plus diversifiée que prévue. Dans l'étude actuelle, nous utilisons une approche comparable pour identifier exhaustivement les agents pathogènes (bactéries, virus, et champignons) composant le microbiote pulmonaire associé aux pneumopathies développées en unités de réanimation. L'étude a inclus des patients admis en réanimation et présentant des formes de pneumopathies acquises sous ventilation mécanique (n = 106), de pneumopathies communautaires (n = 32), de pneumopathies nosocomiales sans ventilation mécanique (n = 22) et de pneumopathies d’aspiration (n = 25). Une cohorte de 25 patients admis en réanimation et ne présentant pas de symptômes de pneumopathie a été étudiée comme contrôle. Cette première partie du travail amènera ainsi à réaliser un catalogue exhaustif des agents de pneumopathies nosocomiales ; à connaître la prévalence des agents identifiés et d’identifier les co-infections fréquemment observées, et surtout à vérifier si ces agents peuvent être identifiés ou pas dans les prélèvements respiratoires profonds de patients non symptomatiques. Pour réaliser cette partie du travail, des séries de prélèvements, incluant des prélèvements de lavage broncho-alvéolaire (LBA), des prélèvements de sang et d'urine ont été étudiés. Ces prélèvements ont été testés par des moyens d’identification moléculaire moderne basés sur l’amplification de gènes conservés (gènes16S rDNA des bactéries et gène 18S rDNA des champignons) suivie par clonage et séquençage à grande échelle. D’autres pathogènes atypiques sont ciblés par des tests de PCR avec utilisation d’amorces spécifiques. Nous avons également inclus la culture, la co-culture d’amibes, la détection sérologique d'anticorps dirigés contre des agents sélectionnés et des tests d'antigène urinaire, afin de comparer ces tests de routine aux approches moléculaires. Comme résultats, les tests moléculaires nous ont permis d’identifier un vaste répertoire de 160 espèces bactériennes dont 73 n'ont jamais été précédemment rapportées à l’étiologie des pneumopathies. En outre, nous avons trouvé 37 phylotypes bactériens potentiellement nouveaux. Nous avons également identifié 24 espèces de champignons dont 6 n'ont pas été précédemment rapportées à l’étiologie des pneumopathies, 7 virus et étonnamment 6 espèces de plantes. De plus, certains agents pathogènes considérés comme typiques aux pneumopathies nosocomiales tels que Pseudomonas aeruginosa et des Streptococci ont été détectés chez les contrôles comme chez les patients. Cet étonnant résultat souligne l'existence d'un noyau de microbiote pulmonaire.Dans un deuxième travail, faisant suite aux travaux effectués dans notre laboratoire et qui ont pu mettre en évidence que 19% des pneumopathies nosocomiales étaient déterminées par des microorganismes associés aux amibes (MAAs) de l’eau préalablement ignorés ou négligés, nous avons utilisé un test d'immunofluorescence multiplexe pour tester la prévalence des anticorps contre les MAAs dans le sang de patients admis en réanimation et atteints de pneumopathies et la comparer à la prévalence au moment de l'admission. Comme résultat, nous démontrons que certains MAAs peuvent être plus fréquemment détectés après des épisodes de pneumopathies nosocomiales que lors de l’admission. En outre, la réponse immunitaire aux MAAs semble augmenter lorsque le séjour en réanimation est prolongé. Enfin, nous avons mis au point une stratégie de metagénomique pour tester les prélévements pour lesquels aucune étiologie n’a été retrouvée. [...] / Recently, bacterial microbiota from a limited number of patients with cystic fibrosis and ventilator-associated pneumonia (VAP) was studied using 16S rDNA gene amplification followed by clone libraries construction and sequencing. These studies have showed that the microbial population of patients with respiratory infections was more diverse than expected. In the current study, we use a similar approach to identify exhaustively the pathogens (bacteria, viruses, and fungi) comprising the microbiota associated with episodes of pneumonia developed in the intensive care units (ICU). Our study included patients admitted to ICUswith with episodes of ventilator-associated pneumonia (n = 106), community-acquired pneumonia (n = 32), nosocomial pneumonia without mechanical ventilation (n = 22) and aspiration pneumonia (n = 25). A cohort of 25 patients admitted to ICUs without symptoms of pneumonia were studied as controls. This first part of the work enables to prepare an exhaustive repertoire of nosocomial pneumonia pathogenes; to know the prevalence of the pathogens identified and to identify co-infections frequently observed, and especially to ascertain whether these agents can be identified or not in the respiratory samples of patients without symptoms of pneumonia. To perform this part of work, series of samples, including bronchoalveolar lavage (BAL) samples, blood samples and urine samples were collected. These samples were tested by means of modern molecular tools based on the amplification of conserved genes (bacterial 16S rDNA and fungal 18S rDNA genes), followed by highthroutput cloning and sequencing. The atypical pathogens are targeted by PCR tests using specific primers and probes. We also included culture, amoeba co-culture, serological detection of antibodies against selected agents and urinary antigen testing, to compare these routine tests to molecular approaches. Based on molecular testing, we identified a wide repertoire of 160 bacterial species of which 73 were never previously reported in pneumonia samples. Moreover, we found 37 putative new bacterial phylotypes. We also identified 24 fungal species of which 6 have not been previously reported in pneumonia, 7 viruses and surprisingly 6 plant species. Some pathogens considered being typical for ICU pneumonia such as Pseudomonas aeruginosa and Streptococcus species may be detected as commonly in controls as in pneumonia patients which strikingly highlight the existence of a core of pulmonary microbiota.In a second work, following previous works performed in our laboratory which were able to show that 19% of nosocomial pneumonia were determined by micro-organisms associated to amoebae (AAMs) previously ignored or neglected, we used a recent test based on multiplex serology to test for the prevalence of antibodies against the AAMs in the blood of patients admitted to ICU and developed episodes of pneumonia and compare it to the prevalence at the time of admission (controls). As a result, we demonstrate that some AAMs may be more frequently detected after episodes of nosocomial pneumonia than at the admission. In addition, the immune response to AAMS appears to increase when the ICU stay is prolonged.Finally, in order to explore samples for which no microbial aetiology was found, we have developed a subtractive hybridization metagenomic strategy and tested it on different clinical samples. The sensitivity of this strategy was also evaluated. We have demonstrated that our method, based on the detection of DNA and RNA of microorganisms in a single test, allows sensitive detection of different types of microorganisms.

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