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RATIONALE Hyperpolarized 129Xe MRI has been proven to be a highly sensitive probe for regional lung function and previous work has shown the sensitivity of 129Xe MRI-derived parameters for inflammatory changes after lung provocation by lipopolysaccharide (LPS) in an animal model [1]. Purpose of this work was to investigate the feasibility of monitoring changes in regional lung function parameters after segmental LPS challenge using hyperpolarized 129Xe MRI in humans. METHODS This study was approved by the institutional ethics review board and thirteen healthy volunteers were recruited. Hyperpolarized 129Xe MRI sessions were performed one week before (baseline) and 24h after segmental LPS challenge (provocation). Bronchoalveolar lavage was performed in the challenged segment and inflammatory cells (neutrophils, macrophages, lymphocytes and monocytes) were assessed. The MR protocol included dissolved-phase imaging and subsequent high-resolution 3D ventilation imaging during the same breath-hold after inhalation of 1L of hyperpolarized 129Xe and a variable amount of air to reach 1/3 of forced vital capacity [2]. 129Xe signals were separated into gaseous 129Xe (GP), 129Xe in aqueous solution (tissue and blood plasma, TP), and in red blood cells (RBC). A ratio map of ventilation after provocation compared to baseline imaging was derived. Using a region-growing algorithm regions of mildly decreased ventilation in the challenged segments were automatically identified and used as regions of interest (ROIs) for further data analysis. RESULTS Ten volunteers successfully completed the study protocol and were included for data analysis. The figure shows exemplary ventilation images from one volunteer along with the corresponding ventilation ratio map, the ROI used for data analysis and dissolved-phase imaging data (top row). The average RBC-TP ratio in the ROI applied to co-registered dissolved-phase imaging data was significantly lower after provocation (two-sided Wilcoxon signed-rank test, p = 0.0039), whereas the average TP-GP ratio was significantly elevated (p = 0.0488, bottom row). No significant correlation of imaging-derived parameters with the amount of inflammatory cells was found after LPS challenge. However, there was a trend of an inverse correlation of RBC-TP and number of neutrophilic granulocytes (Spearman's r = -0.45, p = 0.18). CONCLUSIONS Lung areas with segmental LPS challenge show a local reduction in the gas-uptake parameter RBC-TP, likely due to pulmonary edema causing expansion of the interstitial space in the lung parenchyma. Hyperpolarized 129Xe dissolved-phase imaging may have added value to lavage fluid analysis. REFERENCES [1] Ma&nsson et al., Magn Reson Med 2003;50:1170-1179 [2] Qing et al., NMR Biomed 2014;27:1490-1501

Purpose To evaluate oxygen-enhanced T1-mapping magnetic resonance (MR) imaging as a noninvasive method for visualization and quantification of regional inflammation after segmental allergen challenge in asthmatic patients compared with control subjects. Materials and Methods After institutional review board approval, nine asthmatic and four healthy individuals gave written informed consent. MR imaging (1.5 T) was performed by using an inversion-recovery snapshot fast low-angle shot sequence before (0 hours) and 6 hours and 24 hours after segmental allergen challenge by using either normal- or low-dose allergen or saline. The volume of lung tissue with increased relaxation times was determined by using a threshold-based method. As a biomarker for oxygen transfer from the lungs into the blood, the oxygen transfer function (OTF) was calculated. After the third MR imaging examination, eosinophils in bronchoalveolar lavage fluid were counted. Differences between times and segments were analyzed with nonparametric Wilcoxon matched-pairs test and Spearman correlation. Results In lung segments treated with the standard dose of allergen, the OTF was decreased at 6 hours in asthmatic patients, compared with saline-treated segments (P = .0078). In asthmatic patients at 24 hours, the volume over threshold was significantly increased in normal allergen dose-treated segments compared with saline-treated segments (P = .004). In corresponding lung segments, the volume over threshold at 24 hours in the asthmatic group showed a positive correlation (r = 0.65, P = .0001) and the OTF at 6 hours showed an inverse correlation (r = -0.67, P = .0001) with the percentage of eosinophils in the bronchoalveolar lavage fluid. Conclusion OTF and volume over threshold are noninvasive MR imaging-derived parameters to visualize and quantify the regional allergic reaction after segmental endobronchial allergen challenge.

Involving stakeholders in the context of both business planning and environmental management is important to ensure joint understanding of prevailing or potential problems and risks, the objectives of different parties, and the best ways to attain them. This report presents a study concerning the sustainable development of small ports in the Eastern Gulf of Finland. Ten stakeholders, involving boaters and port actors, from two countries, Finland and Estonia, were interviewed to analyze how stakeholders communicate and think about the concept of sustainability and its materialization in the planning and development of small ports. The report also compares how the definition of sustainability, or thoughts concerning sustainable development, differ between boaters and port actors. Theoretically speaking, the concept of sustainable development should consist of a balance between three aspects: environment, economic and social. Following an explanation of the three-aspect concept, the interviewed stakeholders accepted the idea of sustainable development being based on these three aspects; however, the weighting of aspects varied between the interviewee groups. Although the environmental perspective was important for both boaters and port actors, boaters valued the environment more socio-ecologically than port actors, who had a more economically-oriented perspective. The interviewed boaters valued safety the highest, acknowledging many things should be improved in small ports. Port actors, instead, seemed quite unaware of the challenges boaters face regarding both safety and maintaining sewage-holding-tank pumpout stations. These differences indicate the potential need for more active communication between the two groups. The analysis concretely shows that practical management actions and investments made in small ports are typically related to more than one of the three elements of sustainability. Consequently, evaluation of various decisions’ cost-effectiveness requires holistic planning. Sustainability as an objective is incompatible with short-term thinking, requiring a longer-time perspective. Observed short contracts of port actors remarkably hindered sustainability. Interviewees mutually agreed on the high potential of small ports to bring added value both economically and socially to their surrounding areas. Thus, one important question is: who should fund the investments to develop the long-term sustainability of ports? This report consists of a description of the interviewing method and a thorough analysis of the results. The results lead from recommendations and ideas for the future development of sustainable small ports.