995 resultados para Lung Transplantation


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For patients with chronic lung diseases, such as chronic obstructive pulmonary disease (COPD), exacerbations are life-threatening events causing acute respiratory distress that can even lead to hospitalization and death. Although a great deal of effort has been put into research of exacerbations and potential treatment options, the exact underlying mechanisms are yet to be deciphered and no therapy that effectively targets the excessive inflammation is available. In this study, we report that interleukin-1β (IL-1β) and interleukin-17A (IL-17A) are key mediators of neutrophilic inflammation in influenza-induced exacerbations of chronic lung inflammation. Using a mouse model of disease, our data shows a role for IL-1β in mediating lung dysfunction, and in driving neutrophilic inflammation during the whole phase of viral infection. We further report a role for IL-17A as a mediator of IL-1β induced neutrophilia at early time points during influenza-induced exacerbations. Blocking of IL-17A or IL-1 resulted in a significant abrogation of neutrophil recruitment to the airways in the initial phase of infection or at the peak of viral replication, respectively. Therefore, IL-17A and IL-1β are potential targets for therapeutic treatment of viral exacerbations of chronic lung inflammation.

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Tracheobronchial aspergillosis is a rare entity mainly observed in immune-compromised patients or those who have undergone transplantation. It may cause airway ulcerations or bleeding. We report the case of a 17-year-old patient receiving chemotherapy for acute lymphoblastic leukemia who presented with right-sided tension pneumothorax. Chest tube drainage revealed a massive air leak without reexpansion of the lung, and bronchoscopy showed a 15- × 15-mm defect of the distal trachea related to aspergillosis infection. The defect was closed by an intrathoracic transposition of a pedicled latissimus dorsi muscle flap, which was sutured into the debrided defect followed by temporary endotracheal stenting and antifungal medication.

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Quality of life has been extensively discussed in acute and chronic illnesses. However a dynamic model grounded in the experience of patients in the course of transplantation has not been to our knowledge developed. In a qualitative longitudinal study, patients awaiting solid organ transplantation participated in semi-structured interviews: Exploring topics pre-selected on previous research literature review. Creative interview was privileged, open to themes patients would like to discuss at the different steps of the transplantation process. A qualitative thematic and reflexive analysis was performed, and a model of the dimensions constitutive of quality of life from the perspective of the patients was elaborated. Quality of life is not a stable construct in a long lasting illness-course, but evolves with illness constraints, treatments and outcomes. Dimensions constitutive of quality of life are defined, each of them containing different sub-categories depending on the organ related illness co-morbidities and the stage of illness-course.

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Impairment of lung liquid absorption can lead to severe respiratory symptoms, such as those observed in pulmonary oedema. In the adult lung, liquid absorption is driven by cation transport through two pathways: a well-established amiloride-sensitive Na(+) channel (ENaC) and, more controversially, an amiloride-insensitive channel that may belong to the cyclic nucleotide-gated (CNG) channel family. Here, we show robust CNGA1 (but not CNGA2 or CNGA3) channel expression principally in rat alveolar type I cells; CNGA3 was expressed in ciliated airway epithelial cells. Using a rat in situ lung liquid clearance assay, CNG channel activation with 1 mM 8Br-cGMP resulted in an approximate 1.8-fold stimulation of lung liquid absorption. There was no stimulation by 8Br-cGMP when applied in the presence of either 100 μM L: -cis-diltiazem or 100 nM pseudechetoxin (PsTx), a specific inhibitor of CNGA1 channels. Channel specificity of PsTx and amiloride was confirmed by patch clamp experiments showing that CNGA1 channels in HEK 293 cells were not inhibited by 100 μM amiloride and that recombinant αβγ-ENaC were not inhibited by 100 nM PsTx. Importantly, 8Br-cGMP stimulated lung liquid absorption in situ, even in the presence of 50 μM amiloride. Furthermore, neither L: -cis-diltiazem nor PsTx affected the β(2)-adrenoceptor agonist-stimulated lung liquid absorption, but, as expected, amiloride completely ablated it. Thus, transport through alveolar CNGA1 channels, located in type I cells, underlies the amiloride-insensitive component of lung liquid reabsorption. Furthermore, our in situ data highlight the potential of CNGA1 as a novel therapeutic target for the treatment of diseases characterised by lung liquid overload.

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Despite intensive research efforts, the aetiology of the majority of chronic lung diseases (CLD) in both, children and adults, remains elusive. Current therapeutic options are limited, providing only symptomatic relief, rather than treating the underlying condition, or preventing its development in the first place. Thus, there is a strong and unmet clinical need for the development of both, novel effective therapies and preventative strategies for CLD. Many studies suggest that modifications of prenatal and/or early postnatal lung development will have important implications for future lung function and risk of CLD throughout life. This view represents a fundamental change of current pathophysiological concepts and treatment paradigms, and holds the potential to develop novel preventative and/or therapeutic strategies. However, for the successful development of such approaches, key questions, such as a clear understanding of underlying mechanisms of impaired lung development, the identification and validation of relevant preclinical models to facilitate translational research, and the development of concepts for correction of aberrant development, all need to be solved. Accordingly, a European Science Foundation Exploratory Workshop was held where clinical, translational and basic research scientists from different disciplines met to discuss potential mechanisms of developmental origins of CLD, and to identify major knowledge gaps in order to delineate a roadmap for future integrative research.

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BACKGROUND: Platinum-based doublet chemotherapy is recommended to treat advanced non-small-cell lung cancer (NSCLC) in fit, non-elderly adults, but monotherapy is recommended for patients older than 70 years. We compared a carboplatin and paclitaxel doublet chemotherapy regimen with monotherapy in elderly patients with advanced NSCLC. METHODS: In this multicentre, open-label, phase 3, randomised trial we recruited patients aged 70-89 years with locally advanced or metastatic NSCLC and WHO performance status scores of 0-2. Patients received either four cycles (3 weeks on treatment, 1 week off treatment) of carboplatin (on day 1) plus paclitaxel (on days 1, 8, and 15) or five cycles (2 weeks on treatment, 1 week off treatment) of vinorelbine or gemcitabine monotherapy. Randomisation was done centrally with the minimisation method. The primary endpoint was overall survival, and analysis was done by intention to treat. This trial is registered, number NCT00298415. FINDINGS: 451 patients were enrolled. 226 were randomly assigned monotherapy and 225 doublet chemotherapy. Median age was 77 years and median follow-up was 30.3 months (range 8.6-45.2). Median overall survival was 10.3 months for doublet chemotherapy and 6.2 months for monotherapy (hazard ratio 0.64, 95% CI 0.52-0.78; p<0.0001); 1-year survival was 44.5% (95% CI 37.9-50.9) and 25.4% (19.9-31.3), respectively. Toxic effects were more frequent in the doublet chemotherapy group than in the monotherapy group (most frequent, decreased neutrophil count (108 [48.4%] vs 28 [12.4%]; asthenia 23 [10.3%] vs 13 [5.8%]). INTERPRETATION: Despite increased toxic effects, platinum-based doublet chemotherapy was associated with survival benefits compared with vinorelbine or gemcitabine monotherapy in elderly patients with NSCLC. We feel that the current treatment paradigm for these patients should be reconsidered. FUNDING: Intergroupe Francophone de Cancérologie Thoracique, Institut National du Cancer.

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Previous studies have associated activating Killer cell Immunoglobulin-like Receptor (KIR) genes with protection from cytomegalovirus (CMV) replication after organ transplantation. Whether KIR-associated protection is operating in the context of primary infection, re-activation, or both, remains unknown. Here we correlated KIR genotype and CMV serostatus at the time of transplantation with rates of CMV viremia in 517 heart (n=57), kidney (n=223), liver (n=165) or lung (n=72) allograft recipients reported to the Swiss Transplant Cohort Study. Across the entire cohort we found B haplotypes-which in contrast to A haplotypes may contain multiple activating KIR genes-to be protective in the most immunosuppressed patients (receiving anti-thymocyte globulin induction and intensive maintenance immunosuppression) (hazard ratio after adjustment for covariates 0.46, 95% confidence interval 0.29-0.75, P=0.002). Notably, a significant protection was detected only in recipients who were CMV-seropositive at the time of transplantation (HR 0.45, 95% CI 0.26-0.77, P=0.004), but not in CMV seronegative recipients (HR 0.59, 95% CI 0.22-1.53, P=0.28). These data indicate a prominent role for KIR-and presumably natural killer (NK) cells-in the control of CMV replication in CMV seropositive organ transplant recipients treated with intense immunosuppression.

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High altitude constitutes an exciting natural laboratory for medical research. While initially, the aim of high-altitude research was to understand the adaptation of the organism to hypoxia and find treatments for altitude-related diseases, over the past decade or so, the scope of this research has broadened considerably. Two important observations led to the foundation for the broadening of the scientific scope of high-altitude research. First, high-altitude pulmonary edema (HAPE) represents a unique model which allows studying fundamental mechanisms of pulmonary hypertension and lung edema in humans. Secondly, the ambient hypoxia associated with high-altitude exposure facilitates the detection of pulmonary and systemic vascular dysfunction at an early stage. Here, we review studies that, by capitalizing on these observations, have led to the description of novel mechanisms underpinning lung edema and pulmonary hypertension and to the first direct demonstration of fetal programming of vascular dysfunction in humans.

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BACKGROUND: Stem cell labeling with iron oxide (ferumoxide) particles allows labeled cells to be detected by magnetic resonance imaging (MRI) and is commonly used to track stem cell engraftment. However, the validity of MRI for distinguishing surviving ferumoxide-labeled cells from other sources of MRI signal, for example, macrophages containing ferumoxides released from nonsurviving cells, has not been thoroughly investigated. We sought to determine the relationship between the persistence of iron-dependent MRI signals and cell survival 3 weeks after injection of syngeneic or xenogeneic ferumoxides-labeled stem cells (cardiac-derived stem cells) in rats. METHODS AND RESULTS: We studied nonimmunoprivileged human and rat cardiac-derived stem cells and human mesenchymal stem cells doubly labeled with ferumoxides and beta-galactosidase and injected intramyocardially into immunocompetent Wistar-Kyoto rats. Animals were imaged at 2 days and 3 weeks after stem cell injection in a clinical 3-T MRI scanner. At 2 days, injection sites of xenogeneic and syngeneic cells (cardiac-derived stem cells and mesenchymal stem cells) were identified by MRI as large intramyocardial signal voids that persisted at 3 weeks (50% to 90% of initial signal). Histology (at 3 weeks) revealed the presence of iron-containing macrophages at the injection site, identified by CD68 staining, but very few or no beta-galactosidase-positive stem cells in the animals transplanted with syngeneic or xenogeneic cells, respectively. CONCLUSIONS: The persistence of significant iron-dependent MRI signal derived from ferumoxide-containing macrophages despite few or no viable stem cells 3 weeks after transplantation indicates that MRI of ferumoxide-labeled cells does not reliably report long-term stem cell engraftment in the heart.

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Residual lung function abnormalities have been investigated in 9 children (4 boys and 5 girls) a mean 2.7 years after surviving severe adult respiratory distress syndrome (ARDS). All patients had been artificially ventilated for an average of 9.4 days with a FiO2 greater than 0.5 for 34 hours and maximal PEEP levels in the range of 8-20 cm H2O. Since the ARDS, 3 children had presented recurrent respiratory symptoms (moderate exertional dyspnea and cough) and 2 had had evidence of fibrosis on chest radiographs. In all patients abnormal lung functions were found, i.e. ventilation inequalities (8), hypoxemia (7), and obstructive (2) and restrictive (1) lung disease. A significant correlation between respirator therapy and residual lung function was found (duration of FiO2 greater than 0.5 in hours and inspiratory plateau pressure during respirator therapy vs. ventilation inequalities and hypoxemia).

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RESUME : Valganciclovir (Valcyte®) is an orally administered ester prodrug of the standard anticytomegalovirus (CMV) drug ganciclovir. This drug enabled an important reduction of the burden of CMV morbidity and mortality in solid organ transplant recipients. Prevention of CMV infection and treatment of CMV disease requires drug administration during many weeks. Oral drug administration is therefore convenient. Valganciclovir has been developed to overcome the poor oral availability of ganciclovir, which limits its concentration exposure after oral administration and thus its efficacy. This prodrug crosses efficiently the intestinal barrier, is then hydrolyzed into ganciclovir, providing exposure similar to intravenous ganciclovir. Valganciclovir is now preferred for the prophylaxis and treatment of CMV infection in solid organ transplant recipients. Nevertheless, adequate dosage adjustment is necessary to optimize its use, avoiding either insufficient or exaggerate exposure related to differences in its pharmacokinetic profile between patients. The main goal of this thesis was to better describe the pharmacokinetic and pharmacodynamic profile of valganciclovir in solid organ transplant recipients, to assess their reproducibility and their predictability, and thus to evaluate the current recommendations for valganciclovir dosage adjustment and the potential contribution of routine therapeutic drug monitoring (TDM) to patients' management. A total of 437 ganciclovir plasma concentration data from 65 transplant patients (41 kidney, 12 lung, 10 heart and 2 liver recipients, 58 under oral valganciclovir prophylaxis, 8 under oral valganciclovir treatment and 2 under intravenous ganciclovir) were measured using a validated chromatographic method (HPLC) developed for this study. The results were analyzed by non-linear mixed effect modeling (NONMEM). A two-compartment model with first-order absorption appropriately described the data. Systemic clearance was markedly influenced by GFR, with further differences between graft types and sex (CL/GFR = 1.7 in kidney, 0.9 in heart and 1.2 in lung and liver recipients) with interpatient variability (CV%) of 26% and interoccasion variability of 12%. Body weight and sex influenced central volume of distribution (V1 = 0.34 l/kg in males and 0.27 l/kg in females) with an interpatient variability of 20%. Residual intrapatient variability was 21 %. No significant drug interaction influenced GCV disposition. VGC prophylactic efficacy and tolerability were good, without detectable dependence on GCV profile. In conclusion, this analysis highlights the importance of thorough adjustment of VGC dosage to renal function and body weight. Considering the good predictability and reproducibility of GCV profile after oral VGC in solid organ transplant recipients, routine TDM does not appear to be clinically indicated. However, GCV plasma measurement may still be helpful in specific clinical situations such as documentation of appropriate exposure in patients with potentially compromised absorption, or lack of response to CMV disease treatment, or under renal replacement therapy. RESUME : Le valganciclovir (Valcyte®) est un promédicament oral du ganciclovir qui est un anti-infectieux de référence contre les infections à cytomegalovirus (CMV). Cet antiviral a permis de réduire les effets délétères de cette infection jusqu'ici responsable d'une importante morbidité et mortalité chez les transplantés d'organe. La prévention et le traitement de l'infection à CMV sont donc nécessaires mais requièrent l'administration d'un agent antiviral sur une longue période. Un médicament administré par voie orale représente donc un avantage évident. Le valganciclovir a été développé dans le but d'améliorer la faible absorption orale du ganciclovir, et donc son efficacité. Cet ester valylique du ganciclovir traverse plus facilement la barrière gastro-intestinale, puis est hydrolysé en ganciclovir dans la circulation sanguine, produisant une exposition comparable à celle d'une perfusion intraveineuse de ganciclovir. De ce fait, le valganciclovir est devenu largement utilisé pour la prophylaxie mais aussi le traitement de l'infection à CMV. Néanmoins une utilisation optimale de ce nouveau médicament nécessite de bonnes connaissances sur son profil pharmacocinétique afin d'établir un schéma de dose adapté pour éviter tant une surexposition qu'une sous-exposition résultant des différences d'élimination entre les patients. Le but de cette thèse a été d'étudier le profil pharmacocinétique et pharmacodynamique du valganciclovir chez les transplantés d'organe ainsi que sa reproductibilité et sa prédictibilité. Il s'agissait d'apprécier de manière critique le schéma actuellement recommandé pour l'adaptation des doses de valganciclovir, mais aussi la contribution éventuelle d'un suivi des concentrations sanguines en routine. Un total de 437 taux sanguins de ganciclovir ont été mesurés, provenant de 65 patients transplantés d'organe (41 rénaux, 12 pulmonaires, 10 cardiaques et 2 hépatiques, 58 sous une prophylaxie orale de valganciclovir, 8 sous un traitement de valganciclovir et 2 sous un traitement intraveineux). Une méthode de chromatographie liquide à haute performance a été développée et validée pour cette étude. Les résultats ont été ensuite analysés par modélisation non linéaire à effets mixtes (NONMEM). Un modèle à deux compartiments avec absorption de premier ordre a permis de décrire les données. La clairance systémique était principalement influencée par le débit de filtration glomérulaire (GFR), avec une différence entre les types de greffe et les sexes (CL/GFR = 1.7 chez les greffés rénaux, 0.9 pour les greffés cardiaques et 1.2 pour le groupe des greffés pulmonaires et hépatiques) avec un variabilité inter-individuelle de 26% (CV%) et une variabilité inter-occasion de 12%. Le poids corporel ainsi que le sexe avaient une influence sur le volume central de distribution (V1 = 0.34 l/kg chez les hommes et 0.27 l/kg chez les femmes) avec une variabilité inter-individuelle de 20%. La variabilité intra-individuelle résiduelle était de 21 %. Aucune interaction médicamenteuse n'a montré d'influence sur le profil du ganciclovir. La prophylaxie avec le valganciclovir s'est révélée efficace et bien tolérée. En conclusion, cette analyse souligne l'importance d'une adaptation de la dose du valganciclovir à la fonction rénale et au poids du patient. Au vu de la bonne reproductibilité et prédictibilité du profil pharmacocinétique du ganciclovir chez les patients transplantés recevant du valganciclovir, un suivi des concentrations sanguines en routine ne semble pas cliniquement indiqué. Néanmoins, la mesure des taux plasmatiques de ganciclovir peut être utile dans certaines situations particulières, comme la vérification d'une exposition appropriée chez des patients susceptibles d'absorption insuffisante, ou ne répondant pas au traitement d'une infection à CMV ou encore sous épuration extra-rénale. RESUME LARGE PUBLIC : Le valganciclovir est un précurseur capable de libérer du ganciclovir, récemment développé pour améliorer la faible absorption orale de ce dernier. Une fois le valganciclovir absorbé, le ganciclovir libéré dans la circulation sanguine devient efficace contre les infections à cytomégalovirus. Ce virus largement répandu est responsable de maladies insidieuses et parfois graves chez les personnes présentant une baisse des défenses immunitaires, comme les greffés d'organe recevant un traitement anti-rejet. Le ganciclovir est administré pendant plusieurs mois consécutifs soit pour prévenir une infection après la transplantation, soit pour traiter une infection déclarée. La facilité d'administration du valganciclovir par voie orale représente un avantage sur une administration du ganciclovir par perfusion, qui nécessite une hospitalisation. Toutefois, la voie orale peut être une source supplémentaire de variabilité chez les patients, avec un impact potentiel sur l'efficacité ou la toxicité du médicament. Le but de cette étude a été - de décrire le devenir de ce médicament dans le corps humain (dont l'étude relève de la discipline de la pharmacocinétique) - de définir les facteurs cliniques pouvant expliquer les différences de concentration sanguine observées entre les patients sous une posologie donnée - d'explorer les relations entre les concentrations du médicament dans le sang et son efficacité ou la survenue d'effets indésirables (dont l'étude relève de la discipline de la pharmacodynamie). Cette étude a nécessité le développement et la validation, d'une méthode d'analyse pour mesurer la concentration sanguine du ganciclovir, puis son application à 437 échantillons provenant de 65 patients transplantés d'organe solide (41 rénaux, 12 pulmonaires, 10 cardiaques et 2 hépatiques) recevant du valganciclovir. Les résultats des mesures effectuées ont été analysés à l'aide d'un outil mathématique afin d'élaborer un modèle du devenir du médicament dans le sang chez chaque patient et à chaque occasion. Cette étude a permis d'évaluer chez des patients recevant le valganciclovir, la vitesse à laquelle l'organisme absorbe, distribue, puis élimine le médicament. La vitesse d'élimination dépendait étroitement de la fonction rénale, du type de greffe et du sexe alors que la distribution dépendait du poids et du sexe du patient. La variabilité non expliquée par ces facteurs cliniques était modérée et vraisemblablement sans conséquence clinique évidente soit sur l'efficacité ou la tolérance, qui se révèlent très satisfaisantes chez les patients de l'étude. Les observations n'ont pas révélé de relation entre les concentrations de médicament et l'efficacité thérapeutique ou la survenue d'effets indésirables, confirmant que les doses relativement faibles utilisées dans notre collectif de patients suffisaient à produire une exposition reproductible à des concentrations adéquates. En conclusion, le profil (et par conséquent l'absorption) du valganciclovir chez les patients transplantés semble bien prédictible après une adaptation de la dose à la fonction rénale et au poids du patient. Un contrôle systématique des concentrations sanguines n'est probablement pas indiqué en routine, mais cette mesure peut présenter un intérêt dans certaines conditions particulières.

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This overview summarizes recent data on emerging viruses after hematopoietic cell transplantation (HCT), including adenovirus, BK virus, human metapneumovirus (hMPV), and human herpesvirus (HHV) 6. The increased recognition of these infections is due to improved molecular detection methods, increased surveillance and more profound immunosuppression in the host. Adenovirus can cause serious disease especially in T-cell depleted transplant recipients. Adenovirus viremia is an important risk factor for disease in this setting. BK virus has been associated with hemorrhagic cystitis in HCT recipients. BK viremia is significantly associated with hemorrhagic cystitis. hMPV shows a seasonal distribution and can cause fatal pneumonia in HCT recipients. hMPV may be the etiology of some cases previously categorized as idiopathic pneumonia syndrome. HHV-6 commonly leads to viremia in HCT recipients. HHV-6 has been strongly associated with encephalitis and delayed platelet engraftment. Prospective studies are needed to further examine epidemiology, disease associations, and management strategies for these viruses.

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Background We previously reported the results of a phase II study for patients with newly diagnosed primary central nervous system lymphoma treated with autologous peripheral blood stem-cell transplantation (aPBSCT) and response-adapted whole-brain radiotherapy (WBRT). Now, we update the initial results. Patients and methods From 1999 to 2004, 23 patients received high-dose methotrexate. In case of at least partial remission, high-dose busulfan/thiotepa (HD-BuTT) followed by aPBSCT was carried out. Patients refractory to induction or without complete remission after HD-BuTT received WBRT. Eight patients still alive in 2011 were contacted and Mini-Mental State Examination (MMSE) and the European Organisation for Research and Treatment of Cancer quality-of-life questionnaire (QLQ)-C30 were carried out. Results Of eight patients still alive, median follow-up is 116.9 months. Only one of nine irradiated patients is still alive with a severe neurologic deficit. In seven of eight patients treated with HD-BuTT, health condition and quality of life are excellent. MMSE and QLQ-C30 showed remarkably good results in patients who did not receive WBRT. All of them have a Karnofsky score of 90%-100%. Conclusions Follow-up shows an overall survival of 35%. In six of seven patients where WBRT could be avoided, no long-term neurotoxicity has been observed and all patients have an excellent quality of life.