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- Elovsson, Sofia, et al.
(författare)
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Evaluation of nasal barrier dysfunction at acute- and late-phase reactions in a guinea pig model of allergic rhinitis
- 2005
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Ingår i: Vascular Pharmacology. - : Elsevier BV. - 1537-1891. ; 43:4, s. 267-276
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Tidskriftsartikel (refereegranskat)abstract
- Allergic rhinitis is a common disease characterized by the symptoms of pruritus, sneezing, hypersecretion and nasal blockage. Increased mucosal barrier permeability has been suggested to be an indicator for the severity of allergic rhinitis. This study investigates the passage of radiolabelled albumin from the nasal mucosal circulation into the lumen in guinea pigs intraperitoneally sensitized and intranasally challenged with antigen. In order to characterize the allergic rhinitis model, we evaluated a number of potential influencing factors in nasal plasma exudation, including antigen doses, volumes of antigen solution used, and animal position during the nasal lavage, and the conditions of nasal lavage. The number of eosinophils and levels of histamine and leukotriene B4 in the nasal lavage and eosinophils in the nasal mucosa were determined at the early and late phases after antigen challenge. We also compared the effects of topical nasal treatments for allergic rhinitis on nasal inflammatory responses. Our results demonstrate that, in the guinea pig nasal mucosa, topical challenge with antigens induces plasma exudation and histamine release at the acute-phase reaction, and plasma exudation and eosinophil infiltration at the late-phase reaction. These changes are similar to those reported in human allergic rhinitis. Alterations of nasal plasma exudation, histamine release and eosinophil influx were dependent upon the concentrations and volumes of antigens. An antihistamine inhibited the acute-phase reaction partially, whereas budesonide inhibited effects at the late-phase reaction. We suggest that this model of guinea pig allergic rhinitis with the early and late responses may be useful for high-throughout screening of new drugs.
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| 2. |
- Olsson, Lars E, et al.
(författare)
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(1)H and hyperpolarized (3)He MR imaging of mouse with LPS-induced inflammation.
- 2009
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Ingår i: Journal of magnetic resonance imaging : JMRI. - : Wiley. - 1053-1807 .- 1522-2586. ; 29:4, s. 977-81
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To evaluate the lipopolysaccharide (LPS) model of chronic obstructive pulmonary disease (COPD) in mouse with (1)H and hyperpolarized (HP) (3)He MR imaging. MATERIALS AND METHODS: Axial slices of the lung volume were acquired with HP (3)He and (1)H MRI at 4, 24, and 48 h after LPS exposure. A quantitative ventilation index was calculated from two HP (3)He acquisitions. A bronchoalveolar lavage (BAL) for a cell count was performed following magnetic resonance imaging (MRI). RESULTS: The LPS exposure resulted in a significant increase of cells in BAL, with maximum at 48 h. Lesions on (3)He images were characterized by ventilation defects, whereas lesions on (1)H images were hyperintense and were attributed to edema. The number of lesions was at maximum at 48 h. At this time point, and for both (3)He and (1)H MRI, the volume of the lesions was significantly higher for LPS-exposed mice compared to controls. At 4, 24, and 48 h the ventilation index from the (3)He data was significantly smaller for the LPS-exposed animals compared to controls. CONCLUSION: The time point 48 h after LPS exposure was advantageous for MRI evaluation. Functional read-out with (3)He MRI seems to be more sensitive than conventional (1)H MRI.
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| 3. |
- Olsson, Lars E, et al.
(författare)
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1H and hyperpolarized 3He magnetic resonance imaging clearly detect the preventative effect of a glucocorticoid on endotoxin-induced pulmonary inflammation in vivo.
- 2010
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Ingår i: Innate immunity. - : SAGE Publications. - 1753-4267 .- 1753-4259. ; :Feb 3
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Proton ((1)H) magnetic resonance imaging (MRI) can be utilized to quantify pulmonary edema in endotoxin-induced pulmonary inflammation and hyperpolarized (HP) (3)He MRI can assess pulmonary ventilation. Neither of the methods has been applied to assess the impact of a drug on endotoxin-induced pulmonary inflammation in vivo. The aim of the current study was to evaluate the capability of (1)H and HP (3)He MRI to assess the effects of a glucocorticoid on endotoxin-induced pulmonary inflammation in vivo.Materials and Methods: Mice were exposed to an aerosol of either saline or endotoxin (5 mg/ml) for 10 min. Half of the endotoxin-exposed mice were pretreated with a glucocorticoid (budesonide 3 mg/kg; 2 times/day) and the other half with vehicle p.o. The first budesonide treatment was administered 1 h prior to the aerosol inhalation. Forty-eight hours after the aerosol exposure, the mice were anaesthetized for subsequent imaging. Hyperpolarized (3)He was administered and axial MR images of the lungs obtained. Matching (1)H MR images were then acquired. The mice were sacrificed and broncho-alveolar lavage (BAL) samples were harvested to determine total and cell differential counts.Results: The lesion volume on both (1)H and (3)He MRI, were markedly increased by endotoxin exposure (P < 0.001). Budesonide strongly reduced lesion volume (P < 0.001). The BAL cell count correlated strongly with both (3)He (P < 0.001; r = 0.96) and (1)H lesion volumes (P < 0.001; r = 0.97).Conclusions: Hyperpolarized (3)He MRI and (1)H MRI clearly visualized the preventative effect of budesonide on the impact of endotoxin on pulmonary ventilation and edema, respectively. The fact that ventilation defects on (3)He MRI corresponded to findings from conventional (1)H MRI, as well as to counts of BAL inflammatory cells suggests that these imaging techniques constitute promising tools for non-invasive monitoring of pulmonary inflammation in vivo.
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