Search results for "Lung"

MULTI-SCALE ANALYSIS OF LUNG COMPUTED TOMOGRAPHY IMAGES

2007

A computer-aided detection (CAD) system for the identification of lung internal nodules in low-dose multi-detector helical Computed Tomography (CT) images was developed in the framework of the MAGIC-5 project. The three modules of our lung CAD system, a segmentation algorithm for lung internal region identification, a multi-scale dot-enhancement filter for nodule candidate selection and a multi-scale neural technique for false positive finding reduction, are described. The results obtained on a dataset of low-dose and thin-slice CT scans are shown in terms of free response receiver operating characteristic (FROC) curves and discussed.

SPARC regulation of PMN clearance protects from pristane induced lupus and rheumatoid arthritis

2020

AbstractOne step along the pathogenesis of Systemic lupus erythematosus (SLE) is associated with polymorphonuclear leukocyte (PMN) death and their ineffective removal by M2-macrophages. The secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein with unexpected immunosuppressive function in M2-macrophages and myeloid cells. To investigate the role of SPARC in autoimmunity, we adopted a pristane–induced model of lupus in mice, which recapitulates clinical manifestations of human SLE. Sparc-/- mice developed earlier and more severe renal disease, lung and liver parenchymal damage than the WT counterpart. Most prominently, Sparc-/- mice had anticipated and severe occurr…

2014

The lungs are a noted predilection site of acute, latent, and reactivated cytomegalovirus (CMV) infections. Interstitial pneumonia is the most dreaded manifestation of CMV disease in the immunocompromised host, whereas in the immunocompetent host lung-infiltrating CD8 T cells confine the infection in nodular inflammatory foci and prevent viral pathology. By using murine CMV infection as a model, we provide evidence for a critical role of mast cells (MC) in the recruitment of protective CD8 T cells to the lungs. Systemic infection triggered degranulation selectively in infected MC. The viral activation of MC was associated with a wave of CC chemokine ligand 5 (CCL5) in the serum of C57BL/6 m…

Dynamic19F-MRI of pulmonary ventilation using sulfur hexafluoride (SF6) gas

2001

A new method for dynamic imaging of pulmonary wash-in and wash-out kinetics of inhaled sulfur hexafluoride (SF6) gas was developed. Measurements at the fluorine-19 Larmor frequency were performed in pigs using a gradient echo pulse sequence with 0.5 ms echo time and a measurement time of 9.1 s per image. Dynamic MRI was performed during wash-in and wash-out of SF6 gas in mechanically ventilated porcine lungs. A postprocessing strategy was developed for quantitative determination of wash-out time constants in the presence of noise. Mean wash-out constants were 4.78 ± 0.48 breaths vs. 4.33 ± 0.76 breaths for left and right lung when ventilation was performed with low tidal volume, and 1.73 ± …

3He MRI in healthy volunteers: preliminary correlation with smoking history and lung volumes

2000

MRI with hyperpolarized helium-3 (3He) provides high-resolution imaging of ventilated airspaces. The first aim of this 3He-study was to compare observations of localized signal defects in healthy smokers and non-smokers. A second aim was to describe relationships between parameters of lung function, volume of inspired 3He and signal-to-noise ratio. With Ethics Committee approval and informed consent, 12 healthy volunteers (seven smokers and five non-smokers) were studied. Imaging was performed in a 1.5 T scanner using a two-dimensional FLASH sequence at 30V transmitter amplitude (TR/TE/α = 11 ms/4.2 ms/<10°). Known amounts of 3He were inhaled from a microprocessor-controlled delivery device…

The relationship between asthma and allergic rhinitis: exploring the basis for a common pathophysiology

2003

Summary Most patients with asthma also have rhinitis, and the same inflammatory cells and mechanisms are present in bronchial and nasal mucosa, thus leading to the concept of ‘one airway, one disease’. This concept is further substantiated by evidence of nasal inflammation in asthma, and bronchial inflammation and hyperresponsiveness in rhinitis. Endobronchial allergen challenge induces nasal and bronchial symptoms as well as reductions in pulmonary function and nasal patency. Likewise, treating rhinitis can improve the symptoms of asthma. There are some notable pathophysiological differences between the nose and the bronchi, for example airway remodelling appears to be less extensive in th…

Macrophages govern antiviral responses in human lung tissues protected from SARS-CoV-2 infection

2021

SUMMARYThe majority of SARS-CoV-2 infections among healthy individuals result in asymptomatic to mild disease. However, the immunological mechanisms defining effective lung tissue protection from SARS-CoV-2 infection remain elusive. Unlike mice solely engrafted with human fetal lung xenograft (fLX), mice co-engrafted with fLX and a myeloid-enhanced human immune system (HNFL mice) are protected against SARS-CoV-2 infection, severe inflammation, and histopathology. Effective control of viral infection in HNFL mice associated with significant macrophage infiltration, and the induction of a potent macrophage-mediated interferon response. The pronounced upregulation of the USP18-ISG15 axis (a ne…

Remote Ischemic Preconditioning Decreases Oxidative Lung Damage After Pulmonary Lobectomy

2017

BACKGROUND:During lobectomy in patients with lung cancer, the operated lung is often collapsed and hypoperfused. Ischemia/reperfusion injury may then occur when the lung is re-expanded. We hypothesized that remote ischemic preconditioning (RIPC) would decrease oxidative lung damage and improve gas e

Mast cells and the development of allergic airway disease

2008

Murine models have highlighted the importance of T-cells and TH2 cytokines in development of allergen-induced airway disease. In contrast, the role of mast cells for the development of allergic airway disease has been controversial. Recent studies in murine models demonstrate a significant contribution of mast cells during the development of airway hyperresponsiveness and airway inflammation. Furthermore these models have allowed identifying certain mast cell-produced mediators (e.g. histamine and leukotriene B4) to be involved in the recruitment of effector T-cells into the lung. Additionally, mast cell-produced TNF can directly activate TH2 cells and contribute to the development of aller…

Der Pulmonalarteriendruck des Menschen bei Kreislaufver�nderungen im Phenothiazin-Schlaf

1957

An 11 kreislaufgesunden normotonen Versuchspersonen wurden der Brachial- und Lungenarteriendruck synchron im Wachzustand und im Phenothiazin-Schlaf unter dem Einflus von Adrenalin, Effortil, Vasculat, Noradrenalin, Hypophysin, Acetylcholin, Histamin, Orthostase, Bulbusdruck und Carotissinusentlastung untersucht. Im Gegensatz zu erheblichen Druckveranderungen in der Brachialarterie konnten bei samtlichen Untersuchungen keine vergleichbaren Veranderungen des Pulmonalarteriendruckes gefunden werden.