Travel vaccines are strongly associated to reduced mortality in prostate cancer patients - a real effect or residual confounding?

Repurposing of existing drugs and vaccines for diseases that they were not originally intended for is a promising research field. Recently there has been evidence that oral cholera vaccine might be used in the treatment of inflammatory disease and some common cancers. Specifically, Ji et al showed that the administration of cholera vaccine after a prostate cancer diagnosis reduced prostate cancer specific mortality rates by almost 50%. In a cohort of men from Stockholm, Sweden, with more detailed cancer data and a higher coverage of exposure to vaccine, we replicated these findings using a marginal structural Cox model. We showed that administration of cholera vaccine after prostate cancer diagnosis is associated with a significant reduction in mortality (HR 0.46, 95% CI 0.31-0.69, p-value 0.0001) even after adjusting for all known confounders. However, the same effect (or even stronger) could be seen for several other traveling vaccines and malaria prophylaxis. Therefore, we conclude that this effect is most likely due to a healthy traveler bias and is an example of residual confounding.

Low morbidity in Danish patients with common variable immunodeficiency disorder infected with severe acute respiratory syndrome coronavirus 2.

BACKGROUND: Manifestations and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are not well documented in patients with common variable immunodeficiency disorder (CVID). METHODS: A Danish nationwide retrospective clinician-reported survey. RESULTS: Eleven patients with CVID and SARS-CoV-2 infection were identified. The median age was 50 years (range 22-72). All were on immunoglobulin replacement therapy. Eight patients had other pre-existing co-morbidities. Three patients were asymptomatic during the SARS-CoV-2 infection while seven developed mild coronavirus disease 2019 (COVID-19). One patient had more severe disease with hypoxia and required oxygen therapy. This patient had multiple co-morbidities including well known risk factors for severe COVID-19. All patients recovered. CONCLUSIONS: The results suggest that CVID may not be a risk factor for severe COVID-19. However, further monitoring of this immunodeficient population is needed to confirm our observation.

The Stockholm3 blood-test predicts clinically-significant cancer on biopsy: independent validation in a multi-center community cohort.

BACKGROUND: Several blood-based tests have been suggested to improve prostate cancer testing. The Stockholm3 test has been shown to reduce the number of prostate biopsies, to decrease detection of low-grade cancer and to maintain the detection rate of ISUP Gleason Group (GG) ≥ 2 cancer in a screening-by-invitation setting. We aimed to validate the performance of the Stockholm3 test in an independent, clinical practice cohort. METHODS: The study-population consisted of 533 men in ages 45-75 without previous diagnosis of prostate cancer scheduled for prostate biopsy at any of three centers in Norway and Sweden. Blood samples for Stockholm3 analysis were drawn prior to systematic prostate biopsies. Clinically significant prostate cancer was defined as any finding of ISUP Grade Group (GG) 2 or higher. We calculated area under the curve (AUC) for predicting prostate cancer at biopsy and calculated. Models including PSA and PSA-density (PSA/prostate volume) were compared to a model including also clinical information, protein levels and single nucleotide polymorphisms (SNP). RESULTS: 263 of 533 (49%) participants were diagnosed with prostate cancer. 162 men had prostate cancer with GG ≥ 2. The Stockholm3 test discriminated better for GG ≥ 2 prostate cancer than PSA in combination with PSA-density AUC 8.9 (95% CI 82.7-89.2) and AUC 74.8 (95% CI 70.3-79.3). Using a Stockholm3 cut-off of 10% risk of GG ≥ 2 cancer, 38% of the biopsy procedures were saved, however delaying diagnosis for 6% (n = 10) of men with GG ≥ 2 cancer. Using PSA-density 0.1 as cut-off for biopsy saved 35% of biopsies, delaying diagnosis for 16% (n = 26) of men with GG ≥ 2 cancer. CONCLUSION: A prediction model including clinical information, protein levels and SNPs was independently validated in a clinical practice cohort and reduces the number of un-necessary biopsies while delaying diagnosis for a limited number of men.

Evolution of cystectomy care over an 11-year period in a high-volume tertiary referral centre.

OBJECTIVES: To describe the evolution in radical cystectomy (RC) care over 11 years at a referral centre. PATIENTS AND METHODS: The clinical data of patients undergoing either open RC (ORC) or robot-assisted RC (RARC) for cT1-4aN0M0 bladder cancer (BCa) at our centre between January 2006 and December 2016 were retrospectively evaluated. Crude and propensity score-weighted log-binomial regression analyses were conducted to assess the association between pre- and peri-operative variables and the risk of reoperation, intensive care unit (ICU) admission and death <90 days after RC. RESULTS: A total of 814 patients were considered. The percentage of RARCs performed increased (from 10% to 100%) between 2006 and 2013. Overall, 29% of the patients received neoadjuvant chemotherapy (12-37% from 2006 to 2016). Despite no differences in terms of operating time, pelvic lymph node dissection (PLND) was more commonly attempted during RARC and extended PLND was more frequently performed in the RARC group (72% vs 19%; P < 0.001). Ileal conduit was the preferred urinary diversion in both groups, and more patients in the RARC group underwent neobladder construction (34% vs 14%; P < 0.001). The overall rates of re-intervention, ICU admission and death within 90 days of RC were 8.9%, 5.4% and 2.9%, respectively. On crude analysis, RARC was associated with a reduced risk of ICU admission (relative risk [RR] 0.42, 95% confidence interval [CI] 0.23-0.77; P = 0.005), reintervention (RR 0.58, 95% CI 0.37-0.90; P = 0.015) and death (RR 0.37, 95% CI 0.16-0.85; P = 0.020); however, these risk reductions were not statistically significant on weighted analyses. CONCLUSIONS: The introduction of RARC has coincided with a reduction in the rate of ICU admission, reoperation and death within 90 days of surgery, without compromising operating time, PLND extent or neobladder utilization.

Mortality Rates in Patients With Chronic Hepatitis C and Cirrhosis Compared With the General Population: A Danish Cohort Study.

BACKGROUND: Knowledge about mortality rates (MRs) in patients with chronic hepatitis C (CHC) with cirrhosis is limited. This study aimed to estimate all-cause MRs among patients with CHC with or without cirrhosis in Denmark compared with the general population. METHODS: Patients registered in the Danish Database for Hepatitis B and C with CHC and a liver fibrosis assessment were eligible for inclusion. Liver fibrosis was assessed by means of liver biopsy, transient elastography, and clinical cirrhosis. Up to 20 sex- and age-matched individuals per patient were identified in the general population. Data were extracted from nationwide registries. RESULTS: A total of 3410 patients with CHC (1014 with cirrhosis), and 67 315 matched individuals were included. Adjusted MR ratios (MRRs) between patients with or without cirrhosis and their comparison cohorts were 5.64 (95% confidence interval [CI], 4.76-6.67) and 1.94 (1.55-2.42), respectively. Cirrhosis among patients was associated with an MRR of 4.03 (95% CI, 3.43-4.72). A cure for CHC was associated with an MRR of 0.64 (95% CI, 0.40-1.01) among cirrhotic patients and 2.33 (1.47-3.67) compared with the general population. CONCLUSIONS: MRs were high among patients with CHC with or without cirrhosis compared with the general population. Curing CHC was associated with a reduction in MR among cirrhotic patients, but the MR remained higher than the general population.

Neutral Poly/Per-Fluoroalkyl Substances in Air from the Atlantic to the Southern Ocean and in Antarctic Snow.

The oceanic scale occurrences of typical neutral poly/per-fluoroalkyl substances (PFASs) in the atmosphere across the Atlantic, as well as their air-snow exchange at the Antarctic Peninsula, were investigated. Total concentrations of the 12 PFASs (∑PFASs) in gas phase ranged from 2.8 to 68.8 pg m(-3) (mean: 23.5 pg m(-3)), and the levels in snow were from 125 to 303 pg L(-1) (mean: 209 pg L(-1)). Fluorotelomer alcohols (FTOHs) were dominant in both air and snow. The differences of specific compounds to ∑PFASs were not significant between air and snow. ∑PFASs were higher above the northern Atlantic compared to the southern Atlantic, and the levels above the southern Atlantic <30°S was the lowest. High atmospheric PFAS levels around the Antarctic Peninsula were the results of a combination of air mass, weak elimination processes and air-snow exchange of PFASs. Higher ratios of 8:2 to 10:2 to 6:2 FTOH were observed in the southern hemisphere, especially around the Antarctic Peninsula, suggesting that PFASs in the region were mainly from the long-range atmospheric transport. No obvious decrease of PFASs was observed in the background marine atmosphere after 2005.

Estimating dry deposition and gas/particle partition coefficients of neutral poly-/perfluoroalkyl substances in northern German coast.

Dry deposition fluxes of 12 neutral poly-/perfluoroalkyl substances (PFASs) were estimated at Büsum located in northern German coast, and their gas/particle partition coefficients were predicted by employing the polyparameter linear free energy relationships (PP-LFERs). The gas deposition flux, particle deposition flux and total (gas + particle) flux of the 12 PFASs during sampling periods were 1088 ± 611, 189 ± 75 and 1277 ± 627 pg/(m(2) d), respectively. The gas deposition of PFASs played a key role during deposition to marine ecosystem. Sensitivity analysis showed that wind speed was the most sensitive parameter for gas deposition fluxes. Good agreements (within 1 log unit) were observed between the measured gas/particle partitioning data of PFASs and the predicted partition coefficients using PP-LFERs, indicating the model can reliably predict the gas/particle partitioning behaviors of atmospheric neutral PFASs.

Neutral poly-/perfluoroalkyl substances in air and snow from the Arctic.

Levels of neutral poly-/perfluoroalkyl substances (nPFASs) in air and snow collected from Ny-Ålesund were measured and their air-snow exchange was determined to investigate whether they could re-volatilize into the atmosphere driven by means of air-snow exchange. The total concentration of 12 neutral PFASs ranged from 6.7 to 39 pg m(-3) in air and from 330 to 690 pg L(-1) in snow. A significant log-linear relationship was observed between the gas/particle partition coefficient and vapor pressure of the neutral PFASs. For fluorotelomer alcohol (FTOHs) and fluorotelomer acrylates (FTAs), the air-snow exchange fluxes were positive, indicating net evaporative from snow into air, while net deposition into snow was observed for perfluorooctane sulfonamidoethanols (Me/EtFOSEs) in winter and spring of 2012. The air-snow exchange was snow-phase controlled for FTOHs and FTAs, and controlled by the air-phase for FOSEs. Air-snow exchange may significantly interfere with atmospheric concentrations of neutral PFASs in the Arctic.

Genetic variants in the apoptosis gene BCL2L1 improve response to interferon-based treatment of hepatitis C virus genotype 3 infection.

Genetic variation upstream of the apoptosis pathway has been associated with outcome of hepatitis C virus (HCV) infection. We investigated genetic polymorphisms in the intrinsic apoptosis pathway to assess their influence on sustained virological response (SVR) to pegylated interferon-α and ribavirin (pegIFN/RBV) treatment of HCV genotypes 1 and 3 infections. We conducted a candidate gene association study in a prospective cohort of 201 chronic HCV-infected individuals undergoing treatment with pegIFN/RBV. Differences between groups were compared in logistic regression adjusted for age, HCV viral load and interleukin 28B genotypes. Four single nucleotide polymorphisms (SNPs) located in the B-cell lymphoma 2-like 1 (BCL2L1) gene were significantly associated with SVR. SVR rates were significantly higher for carriers of the beneficial rs1484994 CC genotypes. In multivariate logistic regression, the rs1484994 SNP combined CC+TC genotypes were associated with a 3.4 higher odds ratio (OR) in SVR for the HCV genotype 3 (p=0.02). The effect estimate was similar for genotype 1, but the association did not reach statistical significance. In conclusion, anti-apoptotic SNPs in the BCL2L1 gene were predictive of SVR to pegIFN/RBV treatment in HCV genotypes 1 and 3 infected individuals. These SNPs may be used in prediction of SVR, but further studies are needed.

The spatial distribution of organochlorine pesticides and halogenated flame retardants in the surface sediments of an Arctic fjord: the influence of ocean currents vs. glacial runoff.

Selected organochlorine pesticides (OCs) and halogenated flame retardants (HFRs) were analyzed in surficial fjord sediments collected down the length of Kongsfjorden, Svalbard in the Norwegian high Arctic. Hexachlorocyclohexane (α-HCHs) was found to be the most abundant OC in the sediment, followed by BDE-209>chlordane>α-endosulfan>Dechlorane Plus (anti-DP)>trifluralin concentration ranges were high over the relatively small study area of the fjord (e.g. ∑HCH: 7.2-100 pg g(-1) dry weight (dw)), with concentrations broadly similar to, or lower than, measurements conducted in other parts of the Arctic. Concentrations of legacy OCs, including both HCH isomers and chlordane showed a decreasing trend from the outer, seaward end of the fjord to the inner, glacier end of the fjord. Conversely, sediment concentrations of α- and ß-endosulfan (0.1-12.5 pg g(-1) dw) increased from the outer fjord to the inner fjord. This contrasting pattern may be attributed to the influence of historical vs. contemporary sources of these chemicals to the fjord area, whereby the North Atlantic/West Spitzbergen oceanic current dominates the transport and input of the legacy OCs, whereas atmospheric deposition and meltwater runoff from the glaciers influence the inner fjord sediments for endosulfan. Interestingly, BDE-209 and Dechlorane Plus did not reveal any clear spatial trend. It is plausible that both glacial runoff and oceanic current end members are playing a role in introducing these chemicals to the fjord sediments. The relatively low fractional abundance of the syn-DP isomer (fsyn), however, indicates the long-range transport of this chemical to this Arctic site.

Selected current-use pesticides (CUPs) in coastal and offshore sediments of Bohai and Yellow seas.

China is one of the largest producers, consumers, and traders for pesticides in the world. Currently, there are more than 600 pesticide-active substances registered in China, whereas few studies were conducted to improve our understanding of the occurrence and environmental impact of current-use pesticides (CUPs) in China's environment. In this work, 72 surface sediment samples were taken from the coastal and offshore of Bohai and Yellow seas and were analyzed for six CUPs (trifluralin, dacthal, quintozene, endosulfan, chlorpyrifos, and dicofol) and two metabolites (pentachloroanisole and endosulfan sulfate). Sediment samples were categorized as estuarine or near-shore sediments (Laizhou Bay, Taozi Bay, Sishili Bay, and Jiaozhou Bay) and offshore sediments. Trifluralin, α-endosulfan, endosulfan sulfate, chlorpyrifos, dicofol, and pentachloroanisole were detected in more than 60 % of the samples. Dicofol was the predominant compound with concentrations mostly higher than 100 pg/g dry weight (dw) with the highest concentration of 18,000 pg/g dw. Concentrations of other compounds were mainly below 100 pg/g dw. CUP levels were much lower than the sediment screening benchmark calculated. The highest levels of α-endosulfan, endosulfan sulfate, trifluralin, and chlorpyrifos existed at Laizhou Bay, whereas pentachloroanisole and dicofol had highest mean concentrations at Jiaozhou Bay. Generally, no correlation between pesticide concentrations and total organic carbon was observed either for offshore samples or for near-shore samples.

Brominated flame retardants and Dechloranes in European and American eels from glass to silver life stages.

The populations of American (Anguilla rostrata) and European eels (Anguilla anguilla) have been declining rapidly in the last decades. Organic contaminants are suspected to be one of the possible causes for the decline; however, so far there have been few investigations of the uptake of specific compounds by different life cycle stages (e.g. freshwater or marine stage) and how the contamination patterns develop throughout the eel's life cycle. In the present study we measured concentrations of polybrominated diphenylethers (PBDEs), alternate brominated flame retardants (alternate BFRs) and Dechloranes (Decs) in different life stages of European and American eels to compare the contamination patterns and their development throughout the eel's life cycle. In general, concentrations of flame retardants (FRs) were similar to or higher in American than in European eels, and a greater number of FRs were detected. PBDE congeners that are characteristic of the Penta-PBDE formulation were the most abundant FRs in all adult eels as well as American glass eels. In European glass eels the alternate BFR 2,3-dibromopropyl-2,4,6-tribromophenylether (DPTE) and Dechlorane Plus were the dominating FRs, with average concentrations of 1.1±0.31 ng g(-1) ww and up to 0.32 ng g(-1) ww respectively. Of the PBDEs BDE-183 was the most abundant congener in European glass eels. Low concentrations (less than 10% of the total contamination) of Tetra and Penta-PBDEs in juvenile European eels indicated that bans of technical Penta-PBDE in the European Union are effective. Enrichment of PBDEs was observed over the life stages of both European and American eels. However, a greater relative contribution of PBDEs to the sum FR contamination in American eels indicated an on-going exposure to these substances. High contributions of alternate BFRs in juvenile eels indicated an increased use of these substances in recent years. Concentrations seemed to be driven primarily by location, rather than life stage or age.

Transport of perfluoroalkyl acids in a water-saturated sediment column investigated under near-natural conditions.

The aim of this study was to gain an understanding of the transport of C4-10 perfluoroalkyl carboxylic acids (PFCAs) and C4,6,8 perfluoroalkyl sulfonic acids (PFSAs) in a water-saturated sediment column representing a riverbank filtration scenario under near-natural conditions. Short-chain PFCAs and PFSAs with up to six C-atoms showed complete tracer-like breakthrough. Longer chain ones were retarded due to sorption to the sediment or due to other processes in the aqueous phase. The study reports the first column derived sediment-water partition coefficients ranging from 0.01 cm(3) g(-1) to 0.41 cm(3) g(-1) for C4,6 PFSAs and from 0.0 cm(3) g(-1) to 6.5 cm(3) g(-1) for C4,5,6,8,9 PFCAs. The results clearly indicate that short-chain PFCAs and PFSAs may pose a problem if contaminated surface waters are used for drinking water production via riverbank filtration.

Neutral poly- and perfluoroalkyl substances in air and seawater of the North Sea.

Concentrations of neutral poly- and perfluoroalkyl substances (PFASs), such as fluorotelomer alcohols (FTOHs), perfluoroalkane sulfonamides (FASAs), perfluoroalkane sufonamidoethanols (FASEs), and fluorotelomer acrylates (FTACs), have been simultaneously determined in surface seawater and the atmosphere of the North Sea. Seawater and air samples were taken aboard the German research vessel Heincke on the cruise 303 from 15 to 24 May 2009. The concentrations of FTOHs, FASAs, FASEs, and FTACs in the dissolved phase were 2.6-74, <0.1-19, <0.1-63, and <1.0-9.0 pg L(-1), respectively. The highest concentrations were determined in the estuary of the Weser and Elbe rivers and a decreasing concentration profile appeared with increasing distance from the coast toward the central part of the North Sea. Gaseous FTOHs, FASAs, FASEs, and FTACs were in the range of 36-126, 3.1-26, 3.7-19, and 0.8-5.6 pg m(-3), which were consistent with the concentrations determined in 2007 in the North Sea, and approximately five times lower than those reported for an urban area of Northern Germany. These results suggested continuous continental emissions of neutral PFASs followed by transport toward the marine environment. Air-seawater gas exchanges of neutral PFASs were estimated using fugacity ratios and the two-film resistance model based upon paired air-seawater concentrations and estimated Henry's law constant values. Volatilization dominated for all neutral PFASs in the North Sea. The air-seawater gas exchange fluxes were in the range of 2.5×10(3)-3.6×10(5) pg m(-2) for FTOHs, 1.8×10(2)-1.0×10(5) pg m(-2) for FASAs, 1.1×10(2)-3.0×10(5) pg m(-2) for FASEs and 6.3×10(2)-2.0×10(4) pg m(-2) for FTACs, respectively. These results suggest that the air-seawater gas exchange is an important process that intervenes in the transport and fate for neutral PFASs in the marine environment.

Young doctors' problem solving strategies on call may be improved.

INTRODUCTION: The first year following graduation from medical school is challenging as learning from books changes to workplace-based learning. Analysis and reflection on experience may ease this transition. We used Significant Event Analysis (SEA) as a tool to explore what pre-registration house officers (PRHOs) consider successful and problematic events, and to identify what problem-solving strategies they employ. MATERIAL AND METHODS: A senior house officer systematically led the PRHO through the SEA of one successful and one problematic event following a night call. The PRHO wrote answers to questions about diagnosis, what happened, how he or she contributed and what knowledge-gaining activities the PRHO would prioritise before the next call. RESULTS: By using an inductive, thematic data analysis, we identified five problem-solving strategies: non-analytical reasoning, analytical reasoning, communication with patients, communication with colleagues and professional behaviour. On average, 1.5 strategies were used in the successful events and 1.2 strategies in the problematic events. Most PRHOs were unable to suggest activities other than reading textbooks. CONCLUSION: SEA was valuable for the identification of PRHOs' problem-solving strategies in a natural setting. PRHOs should be assisted in increasing their repertoire of strategies, and they should also be helped to "learn to learn" as they were largely unable to point to new learning strategies. FUNDING: not relevant. TRIAL REGISTRATION: not relevant.

Brominated flame retardants and dechloranes in eels from German Rivers.

The levels of PBDEs, alternate BFRs and dechloranes in European Eel (Anguilla anguilla) samples (elvers, yellow and silver eels) were investigated to compare the contamination of eels from the rivers Elbe and Rhine and to estimate the BFR contamination throughout the eel's life cycle. PBDEs were the dominating flame retardants (FRs) in muscle tissues of yellow and silver eels, while the alternate BFR 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and the Dechlorane 602 were the dominating FRs in elvers (juvenile eels). Concentrations of FRs in silver eels from river Rhine were generally higher than concentrations in other eels analysed with up to 46 ng g(-1) wet weight (ww) ∑PBDEs. The concentrations in yellow and silver eels from river Elbe were similar with an average of 9.0±5.1 ng g(-1)ww and 8.1±3.7 ng g(-1)ww respectively. PBDE concentrations in elvers were comparably low (0.02 (BDE-100) to 0.1 (BDE-183) ng g(-1)ww), which lead to the conclusion that these contaminants were mostly ingested within the rivers. Among the alternate BFRs and dechloranes, DPTE as well as the Dechlorane 602 and Dechlorane Plus (DP) were found in all life cycle stages and rivers with concentrations between 0.01 ng g(-1)ww and 0.7 ng g(-1)ww. Dechlorane 603 could only be detected in silver eels from river Rhine. Pentabromoethylbenzene (PBEB) was only found in yellow and silver eels and bis(2-ethylhexyl)tetrabromophthalate (BEHTBP) could only be detected in elvers. These are the first reports of Dec-602 and 603 in aquatic organisms from Europe. The results of this study show the lasting relevance of PBDEs as contaminants in rivers and river-dwelling species but also the growing relevance of emerging contaminants such as alternate BFRs and dechloranes.

Workflow and scan protocol considerations for integrated whole-body PET/MRI in oncology.

Integrated PET/MRI systems open exciting possibilities for clinical and research applications. However, compared with PET/CT, PET/MRI is a complex technique resulting in new problems and challenges, especially regarding workflow, scan protocols, and data analysis. This complexity applies in particular to examinations in oncology with partial- or whole-body coverage extending over several bed positions. Unlike diagnostic PET/CT, for which the clinical CT protocols can largely be copied from stand-alone CT, the design of a diagnostic MRI protocol for partial- or whole-body coverage is more complex and has to be adapted to the special requirements of PET/MRI to be both time-efficient and comprehensive. Here, we describe basic considerations concerning workflow, imaging protocols, and image analysis for whole-body PET/MRI in oncology, based on our experience with the first integrated PET/MRI scanner. The aim is to fully and optimally make use of the combined PET/MRI measurements in oncology, including identifying and reducing image artifacts as well as optimizing workflow beyond the mere fusion of 2 image datasets.

Attenuation correction for PET/MR: problems, novel approaches and practical solutions.

Attenuation correction in PET is the primary prerequisite for quantification of the radiotracer's signal. Absolute quantification is the key to improve diagnostic performance, to enable comparisons between follow-up examinations and to perform pharmacokinetic modeling. A large fraction of the 511 keV annihilation photons from the positron emitters are scattered by the patient's body. Thus, they are discarded or do not even reach the PET detectors, while others are identified at the wrong location after being scattered. To account for these effects and thus generate quantitative PET images showing the actual activity distribution, it is necessary to determine an attenuation map with the appropriate attenuation coefficients for 511 keV photons at each voxel. In hybrid PET/CT systems, this is achieved using the information about the tissue electron density provided by the CT and adjusting it for the difference in photon energy. In PET/MR systems, there is no mechanism to directly measure the attenuation coefficients of the tissue. Determining the attenuation map in PET/MR is an important challenge involving two problems: the determination of the patient's attenuation map and the determination of the attenuation introduced by additional hardware components. We describe the approaches investigated to deal with these problems and, based on the experience with a fully integrated PET/MR system, we finally discuss potential solutions and limitations in a close to routine setting.

Distribution and long-range transport of polyfluoroalkyl substances in the Arctic, Atlantic Ocean and Antarctic coast.

The global distribution and long-range transport of polyfluoroalkyl substances (PFASs) were investigated using seawater samples collected from the Greenland Sea, East Atlantic Ocean and the Southern Ocean in 2009-2010. Elevated levels of ΣPFASs were detected in the North Atlantic Ocean with the concentrations ranging from 130 to 650 pg/L. In the Greenland Sea, the ΣPFASs concentrations ranged from 45 to 280 pg/L, and five most frequently detected compounds were perfluorooctanoic acid (PFOA), perfluorohexanesulfonate (PFHxS), perfluorohexanoic acid (PFHxA), perfluorooctane sulfonate (PFOS) and perfluorobutane sulfonate (PFBS). PFOA (15 pg/L) and PFOS (25-45 pg/L) were occasionally found in the Southern Ocean. In the Atlantic Ocean, the ΣPFASs concentration decreased from 2007 to 2010. The elevated PFOA level that resulted from melting snow and ice in Greenland Sea implies that the Arctic may have been driven by climate change and turned to be a source of PFASs for the marine ecosystem.