Establishing the European diagnostic reference levels for interventional cardiology

Interventional cardiac procedures may be associated with high patient doses and therefore require special attention to protect the patients from radiation injuries such as skin erythema, cardiovascular tissue reactions or radiation-induced cancer. In this study, patient exposure data is collected from 13 countries (37 clinics and nearly 50 interventional rooms) and for 10 different procedures. Dose data was collected from a total of 14,922 interventional cardiology procedures. Based on these data European diagnostic reference levels (DRL) for air kerma-area product are suggested for coronary angiography (CA, DRL = 35 Gy cm²), percutaneous coronary intervention (PCI, 85 Gy cm²), transcatheter aortic valve implantation (TAVI, 130 Gy cm²), electrophysiological procedures (12 Gy cm²) and pacemaker implantations. Pacemaker implantations were further divided into single-chamber (2.5 Gy cm²) and dual chamber (3.5 Gy cm²) procedures and implantations of cardiac resynchronization therapy pacemaker (18 Gy cm²). Results show that relatively new techniques such as TAVI and treatment of chronic total occlusion (CTO) often produce relatively high doses, and thus emphasises the need for use of an optimization tool such as DRL to assist in reducing patient exposure. The generic DRL presented here facilitate comparison of patient exposure in interventional cardiology.     

Phytoplankton indicator taxa for reference conditions in Northern and Central European lowland lakes

Phytoplankton data from 606 lakes were used to characterize indicator taxa of near-pristine reference conditions in clearwater and humic lowland lakes of Northern and Central Europe. Reference lakes were selected based on low pressure from catchment land-use, low population density and the absence of point sources. Reference lakes had low phytoplankton biomass and taxa richness compared to non-reference lakes. In low alkalinity lakes of Northern Europe, the reference communities had high biomass proportions of chrysophytes and low proportions of cyanobacteria; in the Central European high alkalinity lakes, the biomass was distributed more evenly among algal groups. Indicator species analysis and similarity analysis listed 5–29 taxa indicating reference conditions. Indicator taxa differed especially between the low alkalinity and the high alkalinity lakes, but there were also country-specific differences. Most common indicator taxa for the northern reference lakes were chrysophytes (e.g. Bitrichia, Dinobryon). In the Central European reference lakes, diatoms (e.g. Cyclotella) were more characteristic. Despite the differences, there was a general finding that taxa present in reference lakes were often also present in non-reference lakes, but typically in lower biomass proportions; another characteristic of the reference communities is the absence of many taxa typically found in non-reference lakes.     

Establishing reference intervals for von Willebrand factor multimers

Backgroundvon Willebrand factor (VWF) multimers (VWF:MM) methodologies are technically difficult, laborious, time consuming, non-standardized and results vary between laboratories. A new semi automated VWF:MM assay is available for routine use (Sebia). Due to lack of reference values for VWF:MM fractions, results interpretation can be challenging in some cases. The aim of this study was to determine reference intervals for low molecular weight (LMWM), intermediate molecular weight (IMWM) and high molecular weight (HMWM) multimers.MethodsBy the international cooperation initiated between 4 countries (Estonia, Latvia, France, and USA) 131 samples of relatively healthy individuals were analyzed for VWF:MM (in total 51 males and 80 non-pregnant females aged 17-69 years). Reference intervals were calculated according to CLSI C28-A3 standard.ResultsThe proposed reference intervals for VWF:MM were calculated for LMWM 10.4-22.5%, IMWM 22.6-37.6%, HMWM 45.6-66.6%. Age related differences were seen in IMWM and HMWM (p<0.001 and 0.038). There was no gender related difference observed. Geographically LMWM results of France were different from the other regions (p<0.05).ConclusionsQuantification of VWF:MM fractions, in addition to qualitative assessment of VWF:MM patterns, has the potential to aid in differential diagnosis of von Willebrand disease (VWD) subtypes. The reference values calculated in this study can be used in future research to establish clinical decision limits.     

Establishing micropropagation conditions for five Cotoneaster genotypes

Micropropagation from shoot tips of five Cotoneaster genotypes C. franchetii, C dammeri var. Radicans, C. dammeri Skogholm, C. dammeri Eichholz N° 1 and C. dammeri Streib's Findling) is described. For culture initiation and multiplication, a medium based on Murashige and Skoog basal salts was suitable for all genotypes. For multiplication, 4.4 M 6-benzyladenine provided the optimum results, while auxins proved to be essential for rooting in vitro. However, direct acclimatization of unrooted microcuttings was more efficient than in vitro rooting and acclimatization of rooted plants.Abbreviations BA 6-benzyladenine - GA₃ gibberellic acid - IAA indole-3-acetic acid - IBA indole-3-butyric acid - MS Murashige & Skoog (1962) basal medium - NAA -naphthaleneacetic acid     

The riparian community of north-west European lowland streams

• 1 Riparian plant communities along lowland streams have been affected by man for the past 15000 years. During this period climatological changes have also taken place. The present situation in north-west Europe is a result of these influences so that the choice of reference situations is necessarily arbitrary.
• 2 Dominant abiotic factors that influence riparian vegetation are local hydrology and soil composition, and the pH, lime content and nutrient concentration of the feeding ground water.
• 3 Riparian plant communities are described as phytosociological units. Depending on abiotic characteristics, sequences from spring to lower course and from the stream bank to the boundaries of the stream valley are reported. The Pruno-Fraxinetum association is, and has been for thousands of years, one of the main riparian vegetation types of (lowland) streams.
• 4 In many European countries, restoration projects are being performed or planned. One of the restoration measures is the planting of trees or shrubs along streams as buffer strips. A phytosociological approach, based on knowledge of the local hydrology and nutrient/ion availability, is better by far than the general practice of standard plantation. Such an approach requires research in advance, which increases the initial costs of projects, but can be expected to provide far better results in the long term, and ultimately save money.

     

Standardized nonculture techniques recommended for European reference laboratories

Culture-confirmed diagnosis of meningococcal invasive infections is often hindered by early antibiotic treatment. Nonculture molecular standardized methods are now essential tools for the immediate management of meningococcal infections. The European Monitoring Group on Meningococci (EMGM) recommends the following measures. (1) The implementation of standardized protocols of extraction methods for DNA isolation from clinical specimens for PCR-based identification and genogrouping of Neisseria meningitidis. (2) The use of molecular approaches (sequencing of target genes) for the determination of meningococcal susceptibility to antibiotics, such as sequencing of penA and rpoB genes for susceptibility to penicillin G and rifampicin, respectively. (3) The use of nonculture strain characterization by multilocus sequence typing (MLST) and sequence typing of porA and fetA. These approaches can be implemented either by individual reference laboratories or through collaboration and referral between centres.     

Defining criteria to select reference sites in Mediterranean streams

The European Water Framework Directive establishes the need to define stream type-specific reference conditions to identify “high ecological status”. Methods for selecting reference sites using a priori criteria have been proposed by many authors. A review of these criteria revealed that the most relevant criteria for streams and rivers were those related to riparian vegetation, diffuse and point sources of pollution, river morphology and hydrological conditions and regulation. In this work, we propose 20 criteria that reflect the characteristics of Mediterranean streams and their most frequent disturbances for the selection of reference sites in Mediterranean streams in Spain. We studied 162 sites located in 33 Mediterranean basins belonging to five stream types. Of the locations, 57% were selected as a priori reference sites by having applied the proposed criteria. Reference sites were identified for all stream types except for “large watercourses” which includes the lower reaches of some rivers in this study area. This a priori selection of reference sites was subjected to validation using the macroinvertebrate community by applying of an IBMWP threshold, which is considered to be an indicator of undisturbed sites in Mediterranean streams. This approach determined that whole of this selection (100%) could be considered valid reference sites. Furthermore, we identified differences in the reference conditions for each stream type on the basis of macroinvertebrate assemblage composition. Handling editor: R. Bailey     

Macrophyte communities of European streams with altered physical habitat

The impact of altering hydro-morphology on three macrophyte community types was investigated at 107 European stream sites. Sites were surveyed using standard macrophyte and habitat survey techniques (Mean Trophic Rank Methodology and River Habitat Survey respectively). Principal Components Analysis shows the macrophyte community of upland streams live in a more structurally diverse physical habitat than lowland communities. Variables representing the homogeneity and diversity of the physical environment were used to successfully separate un-impacted from impacted sites, e.g. homogeneity of depth and substrate increased with decreasing quality class for lowland sites (ANOVA p < 0.05). Macrophyte attribute groups and structural metrics such as species richness were successfully linked to hydro-morphological variables indicative of impact. Most links were specific to each macrophyte community type, e.g., the attribute group liverworts, mosses and lichens decreased in abundance with increasing homogeneity of depth and decreasing substrate size at lowland sites but not at upland sites. Elodea canadensis, Sparganium emersum and Potamogeton crispus were indicative of impacted lowland sites. Many of the indicator species are also known to be tolerant to other forms of impact. The potential for a macrophyte tool indicative of hydro-morphological impact is discussed. It is concluded one could be constructed by combining indicator species and metrics such as species richness and evenness.     

Establishing reference values for cervical spine range of motion in pre-pubescent children

Medical professionals, physical therapists, product designers, and computational models all use cervical spine range of motion reference values. To support these functions, researchers have collected a plethora of data to determine the normal range of motion of the cervical spine of adult subjects. However, little to no data exists for subjects under the age of 14. This study utilized the cervical range of motion device, referenced with respect to the Frankfort Plane, to measure the active cervical spine range of motion in all three cardinal planes of the human body, for 106 subjects whose ages ranged from 8 to 10 years. The active range of motion for flexion, extension, lateral extension, and rotation was calculated as 66+/-13 degrees , 85+/-14 degrees , 58+/-8 degrees , and 77+/-7 degrees , respectively, using linear statistics. The observed data significantly differed from the published American Medical Association guidelines for adults but fell within the range of the reference values for 10 year olds. Stratifying and analyzing the range of motion data with respect to gender yielded no significant effect. Appendix A analyzes the data using angular statistics, and produces virtually identical results as those from linear statistics.     

Bacterial tolerances to metals and antibiotics in metal-contaminated and reference streams

Anthropogenic-derived sources of selection are typically implicated as mechanisms for maintaining antibiotic resistance in the environment. Here we report an additional mechanism for maintaining antibiotic resistance in the environment through bacterial exposure to metals. Using a culture-independent approach, bacteria sampled along a gradient of metal contamination were more tolerant of antibiotics and metals compared to bacteria from a reference site. This evidence supports the hypothesis that metal contamination directly selects for metal tolerant bacteria while co-selecting for antibiotic tolerant bacteria. Additionally, to assess how antibiotic and metal tolerance may be transported through a stream network, we studied antibiotic and metal tolerance patterns over three months in bacteria collected from multiple stream microhabitats including the water column, biofilm, sediment and Corbicula fluminea (Asiatic clam) digestive tracts. Sediment bacteria were the most tolerant to antibiotics and metals, while bacteria from Corbicula were the least tolerant. Differences between microhabitats may be important for identifying reservoirs of resistance and for predicting how these genes are transferred and transported in metal-contaminated streams. Temporal dynamics were not directly correlated to a suite of physicochemical parameters, suggesting that tolerance patterns within microhabitats are linked to a complex interaction of the physicochemical characteristics of the stream.     

Biological indices applied to benthic macroinvertebrates at reference conditions of mountain streams in two ecoregions (Poland, the Slovak Republic)

The study was carried out from 2007 to 2010 in two ecoregions: the Carpathians and the Central Highlands. The objectives of our survey were to test the existing biological index metric based on benthic macroinvertebrates at reference conditions in the high- and mid-altitude mountain streams of two ecoregions according to the requirements of the EU WFD and to determine which environmental factors influence the distribution of benthic macroinvertebrates. Our results revealed statistically significant differences in the values of the physical and chemical parameters of water as well as the mean values of metrics between the types of streams at the sampling sites. RDA analysis showed that the temperature of the water, pH, conductivity, the stream gradient, values of the HQA index, and altitude were the parameters most associated with the distribution of benthic macroinvertebrate taxa and the values of the metrics. The values of biological indices should be considered according to the stream typology including altitude and geology. At the reference conditions, the suggested border values of biological indices are very harsh. The values of the biological indices of most sampling sites did not correspond to the requirements of the high status in rivers. The streams at altitudes above 1,200 m a.s.l. should be treated as another river type and new reference values should be established.     

Establishing national diagnostic reference levels (DRLs) for computed tomography in Egypt

ObjectivesTo establish national diagnostic reference levels (DRLs) in Egypt for computed tomography (CT) examinations of adults and identify the potential for optimization.MethodsData from 3762 individual patient’s undergoing CT scans of head, chest (high resolution), abdomen, abdomen-pelvis, chest-abdomen-pelvis and CT angiography (aorta and both lower limbs) examinations in 50 CT facilities were collected. This represents 20% of facilities in the country and all of the 27 Governorates. Results were compared with DRLs of UK, USA, Canada, Japan, Australia and France.ResultsThe Egyptian DRLs for CTDI_vol in mGy are for head: 30, chest (high resolution): 22, abdomen (liver metastasis): 31, abdomen-pelvis: 31, chest-abdomen–pelvis: 33 and CT angiography (aorta and lower limbs): 37. The corresponding DRLs for DLP in mGy.cm are 1360, 420, 1425, 1325, 1320 and 1320. For head CT, the Egyptian DRL for CTDI_vol is 2–3 times lower than the DRLs from other countries. However, the DRL in terms of DLP is in the same range or higher as compared to others. The Egyptian DRL for chest CT (high resolution) is similar to others for DLP but higher for CTDI_vol. For abdomen and abdomen-pelvis DRLs for CTDI_vol are higher than others. For DLP, the DRLs for abdomen are higher than DRL in UK and lower than those in Japan, while for abdomen-pelvis they are higher than other countries.ConclusionDespite lower DRLs for CTDI_vol, an important consistent problem appears to be higher scan range as DRLs for DLP are higher.     

The search for reference conditions for stream vegetation in northern Europe

1. The European Water Framework Directive provides a framework for improving the ecological quality of stream ecosystems, with deviation from reference used as a measure of ecological status.
2. Here we examine the possibility of using less impacted stream sites from Latvia, Lithuania and Poland to establish a Danish reference network for macrophyte assemblages, and as a guiding image for identification of possible references sites within Denmark. Both approaches were evaluated using historical Danish records.
3. Four different macrophyte assemblages were identified for mid-sized streams in the Central and Eastern Lowland ecoregions. Macrophyte assemblages could not be delineated using physical stream site characteristics; however a gradual change in assemblage composition was attributed to differences in alkalinity and human impact.
4. Assemblages of contemporary vegetation in Denmark were quite similar to those found in Polish, Latvian and Lithuanian streams (26–35%). However, more importantly, from species-based predictions we noted higher similarity, particularly with Latvian and Lithuanian streams, before intensive land use commenced in Denmark ( c. 1900). These results show that stream sites from these three countries can be considered in a Danish reference network.
5. Two of the four macrophyte assemblages comprised species such as Fontinalis antipyretica, Myriophyllum spicatum , Nuphar lutea , Potamogeton alpinus and P. perfoliatus that have a very scattered occurrence in the contemporary vegetation in Denmark. These groups were closely associated with the predictions from historic records, thereby lending support the conjecture that these assemblages could be part of the guiding image for the identification of potential reference sites within Denmark.     

Identification and measure of hydromorphological degradation in Central European lowland streams

Hydrobiologia - The objective of the current study was to identify hydromorphological variables that are suitable to define and describe hydromorphological degradation. Stream type-specific and...     

Modelling the hydraulic preferences of benthic macroinvertebrates in small European streams

1. Relating processes occurring at a local scale to the natural variability of ecosystems at a larger scale requires the design of predictive models both to orientate stream management and to predict the effects of larger scale disturbances such as climate changes. Our study contributes to this effort by providing detailed models of the hydraulic preferences of 151 invertebrate taxa, mostly identified at the species level. We used an extensive data set comprising 580 invertebrate samples collected using a Surber net from nine sites of second and third order streams during one, two or three surveys at each site. We used nested non‐linear mixed models to relate taxon local densities to bed shear stresses estimated from FliesswasserStammTisch hemisphere numbers. 2. An average model by taxon, i.e. independent from surveys, globally explained 25% of the density variations of taxa within surveys. A quadratic relationship existed between the average preferences and the niche breadth of taxa, indicating that taxa preferring extreme hemisphere numbers had a reduced hydraulic niche breadth. A more complete model, where taxa preferences vary across surveys, globally explained 38% of the variation of taxa densities within surveys. Variations in preferences across surveys were weak for taxa preferring extreme hemisphere numbers. 3. There was a significant taxonomic effect on preferences computed from the complete model. By contrast, season, site, average hemisphere number within a survey and average density of taxa within a survey used as covariates did not consistently explain shifts in taxon hydraulic preferences across surveys. 4. The average hydraulic preferences of taxa obtained from the extensive data set were well correlated to those obtained from two additional independent data sets collected in other regions. The consistency of taxon preferences across regions supports the use of regional preference curves for estimating the impact of river management on invertebrate communities. By contrast, the hydraulic niche breadths of taxa computed from the different data sets were not related.