| 11. |
- Nettelbladt, Otto S, et al.
(författare)
-
Combined fluorine-18-FDG and carbon-11-methionine PET for diagnosis of tumors in lung and mediastinum
- 1998
-
Ingår i: Journal of Nuclear Medicine. - 0161-5505 .- 1535-5667. ; 39:4, s. 640-647
-
Tidskriftsartikel (refereegranskat)abstract
- We evaluated the value of PET using 18F-fluorodeoxyglucose (FDG) and 11C-methionine, individually or in combination, to distinguish malignant from benign tumors and to identify or exclude mediastinal metastases.METHODS:Seventeen patients with a tumor in the lung or mediastinum were evaluated with 18F-FDG and 11C-methionine PET. For morphological comparison, we used CT, and all findings were confirmed by histology of surgical resection specimens (n = 16) or by cytology (n = 1).RESULTS:All tumors were visualized equally well with both tracers, and there were no false-positive results. In 2 patients with a malignant tumor, coexisting pneumonia was correctly diagnosed as an inflammatory lesion because of its wedge-like shape. PET correctly excluded hilar invasion and mediastinal lymph node metastases in 10 of 14 patients with primary lung tumor. PET identified mediastinal metastases in 4 of 4 patients. CT failed to detect mediastinal tumor spread in 2 patients and gave a false-positive reading in 2 others. Significantly higher uptake (SUV) and transport rate (slope) values were obtained from malignant than benign lesions with both tracers. No major differences were seen in either the levels of significance or accuracy when the two tracers were compared. Slope values did not add further information to what was obtained with SUV. Density correction of SUV and slope values, to avoid the influence of surrounding air as well as tumor heterogeneity, increased these differences somewhat. Both tracers distinguished malignant from benign lesions with a 93% sensitivity and an accuracy of 89%-95%, but sensitivity improved to 100% when values from both tracers were combined.CONCLUSION:Fluorine-18-FDG and 11C-methionine PET visualized all tumors equally well and detected mediastinal spread better than CT. For differentiation purposes, the problems of false-positive and false-negative PET findings could not be safely overcome in a limited number of cases either by the use of both tracers, by the additional use of slope values or by lesion density correction.
|
|
| 12. |
- Relova, Anne-Jacqueline, 1976-
(författare)
-
Mechanisms for and Effects of Airway Epithelial Damage in Asthma
- 2002
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The airway epithelium plays a crucial role in protecting the underlying connective tissue (CT) from noxious agents. Damage and shedding of the epithelium are observed in the airways of asthma, cystic fibrosis and rhinitis patients. The aim of this study was to investigate the mechanisms by which epithelial damage occurs, and the consequences of such damage for the inflammatory process in the airways. In this study, cultured normal human bronchial epithelial cells, excised rat tracheae, and cultured murine mast cells were used as model systems. Metabolic alterations, morphological changes and cell-cell contact stabilities were investigated.The T-helper (Th)-1 cytokines, tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), and interleukin (IL)-1β were found to be pro-inflammatory, leading to major morphological changes, inhibitions in desmosome formation, and accelerated cell death. The Th2 cytokines, IL-4, IL-5, and IL-13 were found to cause no changes in cell death, nitric oxide levels and desmosome formation but instead an increase in proliferation, therefore were anti-inflammatory in this respect.Increasing the osmolarity of the airway surface liquid (ASL) altered the integrity of the tight junction (TJ) and allowed a 4-kDa compound to penetrate the epithelial layer and access the CT. This effect was reversible if the ASL was returned to 295 mOsm. Intentionally breaking the TJ with EGTA and subsequent osmolar changes in ASL demonstrated the importance of TJ and the fragility of the CT under hyperosmolar stress, leading to a disrupted CT with larger capillaries and altered elemental ion content and epithelial denudation. Hydrocortisone was shown to downregulate IL-4-induced IL-6 upregulation in murine mast cells. Furthermore, incubating mast cells with hydrocortisone lead to a new subpopulation that was morphologically unique, that displayed new cell surface markers (CD44 and CD61) and that lacked CD54. These changes modify the interactions of mast cells with surrounding cells in the CT and epithelium.In conclusion, the balance between pro- and anti-inflammatory cytokines and ASL osmolarity may influence the role of the airway epithelium as a barrier. The pharmacological use of hyperosmolarity to disrupt TJ reversibly may help facilitate the delivery of drugs through the airway epithelium.
|
|
| 13. |
- Shahana, Shahida, et al.
(författare)
-
Ultrastructure of bronchial biopsies from patients with allergic and non-allergic asthma
- 2005
-
Ingår i: Respiratory Medicine. - : Elsevier BV. - 0954-6111 .- 1532-3064. ; 99:4, s. 429-443
-
Tidskriftsartikel (refereegranskat)abstract
- Epithelial damage is commonly found in airways of asthma patients. The aim of this study was to investigate epithelial damage in allergic and non-allergic asthma at the ultrastructural level.Bronchial biopsies obtained from patients with allergic asthma (n=11n=11), non-allergic asthma (n=7n=7), and healthy controls (n=5n=5) were studied by transmission electron microscopy.Epithelial damage was found to be extensive in both asthma groups. Both in basal and in columnar cells, relative desmosome length was reduced by 30–40%. In columnar cells, half-desmosomes (i.e., desmosomes of which only one side was present) were frequently noticed. Eosinophils showing piece-meal degranulation were commonly observed in allergic asthma. Degranulating mast cells were more often observed in allergic asthma. Goblet cell hyperplasia was only found in allergic asthma. Lymphocytes were increased in both groups. In both groups, the lamina densa of the basal lamina was thicker than the control by about 40–50%. In allergic asthma the lamina densa was irregular with focal thickening.While there was always a tendency for changes (epithelial damage, desmosomes, degranulating mast cells, basal lamina) to be more extensive in allergic asthma compared to non-allergic asthma, there was no significant difference between the two groups in this respect. Reduced desmosomal contact may be an important factor in the epithelial shedding observed in patients with asthma.
|
|
| 14. |
- Storaas, Torgeir, et al.
(författare)
-
Incidence of rhinitis and asthma related to welding in Northern Europe
- 2015
-
Ingår i: European Respiratory Journal. - : The European Respiratory Society. - 0903-1936 .- 1399-3003. ; 46:5, s. 1290-1297
-
Tidskriftsartikel (refereegranskat)abstract
- Welding-related asthma is well recognised but less is known about rhinitis in relation to welding. The aim here, was to study associations between welding, rhinitis and asthma in a general population sample, and factors influencing selection into and out of a welding occupation.Adult-onset asthma and non-infectious rhinitis were investigated in the international multicentre population-based Respiratory Health in Northern Europe (RHINE) study, including 16 191 responders aged 26-54 years. Ever welding (n=2181), welding >25% of working time (n=747), and welding in stainless steel >6 months (n=173) were assessed by questionnaire. Subjects with rhinitis or asthma onset when aged <18 years were excluded. Incidence rates for asthma and rhinitis were calculated from year of disease onset, and start and end of welding job. Cox's proportional hazard models adjusting for age, sex, parental education and study centre, and Kaplan-Meier curves were used.Rhinitis incidence was higher among welders (hazard ratio (HR) 1.4, 95% CI 1.3-1.6), consistent in men and women, and across centres (pheterogeneity=0.4). In men, asthma incidence was higher among welders (HR 1.4, 95% CI 1.04-1.97). Quitting welding was indicated higher after adult-onset rhinitis (HR 1.1, 95% CI 1.0-1.3).Adult-onset rhinitis and asthma was higher among welders, consistent across population samples from Northern Europe. No pre-employment selection was found, whereas selection out of welding jobs was suggested.
|
|
| 15. |
|
|
