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Passive sampling methods for contaminated sediments: Risk assessment and management
This paper details how activity-based passive sampling methods (PSMs), which provide information on bioavailability in terms of freely dissolved contaminant concentrations (Cfree), can be used to better inform risk management decision making at multiple points in the process of assessing and managing contaminated sediment sites. PSMs can increase certainty in site investigation and management, because Cfree is a better predictor of bioavailability than total bulk sediment concentration (Ctotal) for 4 key endpoints included in conceptual site models (benthic organism toxicity, bioaccumulation, sediment flux, and water column exposures). The use of passive sampling devices (PSDs) presents challenges with respect to representative sampling for estimating average concentrations and other metrics relevant for exposure and risk assessment. These challenges can be addressed by designing studies that account for sources of variation associated with PSMs and considering appropriate spatial scales to meet study objectives. Possible applications of PSMs include: quantifying spatial and temporal trends in bioavailable contaminants, identifying and evaluating contaminant source contributions, calibrating site-specific models, and, improving weight-of-evidence based decision frameworks. PSM data can be used to assist in delineating sediment management zones based on likelihood of exposure effects, monitor remedy effectiveness, and, evaluate risk reduction after sediment treatment, disposal, or beneficial reuse after management actions. Examples are provided illustrating why PSMs and freely dissolved contaminant concentrations (Cfree) should be incorporated into contaminated sediment investigations and study designs to better focus on and understand contaminant bioavailability, more accurately estimate exposure to sediment-associated contaminants, and better inform risk management decisions. Research and communication needs for encouraging broader use are discussed. Integr Environ Assess Manag 2014;10:224–236. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC
3D Real-Time Echocardiography Combined with Mini Pressure Wire Generate Reliable Pressure-Volume Loops in Small Hearts
BACKGROUND:
Pressure-volume loops (PVL) provide vital information regarding ventricular performance and pathophysiology in cardiac disease. Unfortunately, acquisition of PVL by conductance technology is not feasible in neonates and small children due to the available human catheter size and resulting invasiveness. The aim of the study was to validate the accuracy of PVL in small hearts using volume data obtained by real-time three-dimensional echocardiography (3DE) and simultaneously acquired pressure data.
METHODS:
In 17 piglets (weight range: 3.6–8.0 kg) left ventricular PVL were generated by 3DE and simultaneous recordings of ventricular pressure using a mini pressure wire (PVL3D). PVL3D were compared to conductance catheter measurements (PVLCond) under various hemodynamic conditions (baseline, alpha-adrenergic stimulation with phenylephrine, beta-adrenoreceptor-blockage using esmolol). In order to validate the accuracy of 3D volumetric data, cardiac magnetic resonance imaging (CMR) was performed in another 8 piglets.
RESULTS:
Correlation between CMR- and 3DE-derived volumes was good (enddiastolic volume: mean bias -0.03ml ±1.34ml). Computation of PVL3D in small hearts was feasible and comparable to results obtained by conductance technology. Bland-Altman analysis showed a low bias between PVL3D and PVLCond. Systolic and diastolic parameters were closely associated (Intraclass-Correlation Coefficient for: systolic myocardial elastance 0.95, arterial elastance 0.93, diastolic relaxation constant tau 0.90, indexed end-diastolic volume 0.98). Hemodynamic changes under different conditions were well detected by both methods (ICC 0.82 to 0.98). Inter- and intra-observer coefficients of variation were below 5% for all parameters.
CONCLUSIONS:
PVL3D generated from 3DE combined with mini pressure wire represent a novel, feasible and reliable method to assess different hemodynamic conditions of cardiac function in hearts comparable to neonate and infant size. This methodology may be integrated into clinical practice and cardiac catheterization programs and has the capability to contribute to clinical decision making even in small hearts
Metal-macrofauna interactions determine microbial community structure and function in copper contaminated sediments
Peer reviewedPublisher PD
Purification and partial characterization of draculin, the anticoagulant factor present in the saliva of vampire bats (<i>Desmodus rotundus</i>)
From the saliva of the vampire bat Desmodus rotundus, we isolated an unknown anticoagulant protein which we have named draculin. Its molecular mass as determined by non-reduced SDS-PAGE is about 83 kDa. The reduced polypeptide shows a slower migration. HPLC in a molecular sieve matrix yields a single, symmetrical peak corresponding to 88.5 kDa. Isoelectric focusing shows an acidic protein with pI = 4.1–4.2. Aminoacid analysis is compatible with a single chain polypeptide of about 80 kDa. Cyanogen bromide cleavage yields a single 16-aminoacid peptide, corresponding to the amino-terminus of the native molecule. Draculin inhibits the activated form of coagulation factors IX and X. It does not act on thrombin, trypsin, chymotrypsin and does not express fibrinolytic activity. The inhibition is immediate and not readily reversible, with a stoichiometry of about two molecules of draculin per molecule of factor IXa or Xa. Surprisingly, the inhibitory activity against either factor is not affected by the presence of the other. Draculin binds quantitatively to either immobilised factor Xa or factor IXa. Our preliminary interpretation is that there are two forms of draculin that hardly differ in structure. Both bind to factor Xa and to factor IXa but one form inhibits factor Xa and the other inhibits factor IXa. When added to plasma, draculin increases the lag phase as well as the height of the peak of thrombin generation
Diagnosing problems of fine sediment delivery and transfer in a lowland catchment
This paper is a product of research conducted within the REFORM collaborative project funded by the European Union Seventh Framework Programme under grant agreement 282656
Medical treatment of pulmonary hypertension in adults with congenital heart disease. updated and extended results from the International COMPERA-CHD registry
Background: Pulmonary arterial hypertension (PAH) is common in congenital heart disease (CHD). Because clinical-trial data on PAH associated with CHD (PAH-CHD) remain limited, registry data on the long-term course are essential. This analysis aimed to update information from the COMPERA-CHD registry on management strategies based on real-world data. Methods: The prospective international pulmonary hypertension registry COMPERA has since 2007 enrolled more than 10,000 patients. COMPERA-CHD is a sub-registry for patients with PAH-CHD Results: A total of 769 patients with PAH-CHD from 62 specialized centers in 12 countries were included into COMPERA-CHD from January 2007 through September 2020. At the last follow-up in 09/2020, patients [mean age 45.3±16.8 years; 512 (66%) female] had either post-tricuspid shunts (n=359; 46.7%), pre-tricuspid shunts (n=249; 32.4%), complex CHD (n=132; 17.2%), congenital left heart or aortic valve or aortic disease (n=9; 1.3%), or miscellaneous CHD (n=20; 2.6%). The mean 6-minute walking distance was 369±121 m, and 28.2%, 56.0%, and 3.8% were in WHO functional class I/II, III or IV, respectively (12.0% unknown). Compared with the previously published COMPERA-CHD data, after 21 months of followup, the number of included PAH-CHD patients increased by 91 (13.4%). Within this group the number of Eisenmenger patients rose by 39 (16.3%), the number of “Non-Eisenmenger PAH” patients by 45 (26.9%). Currently, among the 674 patients from the PAH-CHD group with at least one follow-up, 450 (66.8%) received endothelin receptor antagonists (ERA), 416 (61.7%) PDE-5 inhibitors, 85 (12.6%) prostacyclin analogues, and 36 (5.3%) the sGC stimulator riociguat. While at first inclusion in the COMPERA-CHD registry, treatment was predominantly monotherapy (69.3%), this has shifted to favoring combination therapy in the current group (53%). For the first time, the nature, frequency, and treatment of significant comorbidities requiring supportive care and medication are described. Conclusions: Analyzing “real life data” from the international COMPERA-CHD registry, we present a comprehensive overview about current management modalities and treatment concepts in PAH-CHD. There was an trend towards more aggressive treatment strategies and combination therapies. In the future, particular attention must be directed to the “Non-Eisenmenger PAH” group and to patients with complex CHD, including Fontan patients
Effect of garlic on cardiovascular disorders: a review
Garlic and its preparations have been widely recognized as agents for prevention and treatment of cardiovascular and other metabolic diseases, atherosclerosis, hyperlipidemia, thrombosis, hypertension and diabetes. Effectiveness of garlic in cardiovascular diseases was more encouraging in experimental studies, which prompted several clinical trials. Though many clinical trials showed a positive effect of garlic on almost all cardiovascular conditions mentioned above, however a number of negative studies have recently cast doubt on the efficary of garlic specially its cholesterol lowering effect of garlic. It is a great challenge for scientists all over the world to make a proper use of garlic and enjoy its maximum beneficial effect as it is the cheapest way to prevent cardiovascular disease. This review has attempted to make a bridge the gap between experimental and clinical study and to discuss the possible mechanisms of such therapeutic actions of garlic
Developing an analytical framework for assessing progress toward ecosystem-based management
Ecosystem-based management (EBM) has become a key instrument of contemporary environmental policy and practice. Given the increasingly important role of EBM, there is an urgent need for improved analytical approaches to assess if and to what extent EBM has been accomplished in any given case. Drawing on the vast literature on EBM, we identify five key ecosystem aspects for assessment. By linking these aspects to four phases of management, we develop an interdisciplinary, analytical framework that enables a high-resolution and systematic assessment of the degree of specificity and integration of ecosystem aspects in an EBM. We then apply the framework to evaluate five coastal EBM initiatives in Sweden, four on the Baltic coast and one on the west coast. Our results demonstrate our framework’s usefulness for in-depth and continuous assessments of processes aiming for EBM, and also provide an empirical basis for inferences about the key challenges for successful EBM. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13280-015-0655-7) contains supplementary material, which is available to authorized users
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