318 research outputs found
Lungenfunktionsveränderungen asbestexponierter Arbeiter, eine systematische Übersicht und Metaanalyse
No full textBackground: A continuing controversy exists about whether, asbestos exposure is associated with significant lung function impairments when major radiological abnormalities are lacking. We conducted a systematic review and meta-analysis in order to assess whether asbestos exposure is related to impairment of lung function parameters independently of the radiological findings.
Methods: MEDLINE was searched from its inception up to April 2010. We included studies that assessed lung function parameters in asbestos exposed workers and stratified subjects according to radiological findings. Estimates of VC, FEV1 and FEV1/VC with their dispersion measures were extracted and pooled.
Results: Our meta-analysis with data from 9,921 workers exposed to asbestos demonstrates a statistically significant reduction in VC, FEV1 and FEV1/VC, even in those workers without radiological changes. Less severe lung function impairments are detected if the diagnoses are based on (high resolution) computed tomography rather than the
less sensitive X-ray images. The degree of lung function impairment was partly related to the proportion of smokers included in the studies.
Conclusions: Asbestos exposure is related to restrictive and obstructive lung function impairment. Even in the absence of radiological evidence of parenchymal or pleural diseases there is a trend for functional impairment
Lung functional failures of aircraft crew members after “fume event”: diagnostics and biomonitoring
No full textTestudo guntheri Baur 1889
No full textTestudo guntheri Baur, 1889 Current name: unclear Syntype (1 specimen): OUM 8656 (articulated skeleton, SCL 79 cm). Remarks: “ Testudo güntheri ” was erected by Baur (1889: p. 1044) for the tortoises that were placed in the species Testudo elephantopus by Günther (1877). The latter author states that he referred five specimens to Testudo elephantopus (pp. 63–64); one from the Oxford Museum (now catalogued as OUM 8656), two further specimens from the collection of the Free Public Museum, Liverpool, and one each from the collections of the British Museum (now Natural History Museum, London) and the Royal College of Surgeons, London. OUM 8656 is depicted on several plates in Günther (1877) and has been catalogued as “ Holotype of Testudo guntheri Baur ” in Oxford. However, it is clear from the list of specimens provided by Günther (1877) that OUM 8656 and the other four tortoises are syntypes. All of these tortoises have no exact locality data. Therefore, Testudo guntheri should best be treated as nomen dubium, although it has been previously identified with giant tortoises from the southwest of Albemarle Island, Galapagos (e.g., Wermuth & Mertens 1977; Fritz & Havaš 2007).Published as part of Nowak-Kemp, Małgosia & Fritz, Uwe, 2010, Chelonian type specimens at the Oxford University Museum, pp. 1-19 in Zootaxa 2604 (1) on page 16, DOI: 10.11646/zootaxa.2604.1.1, http://zenodo.org/record/530226
Asthma bronchiale und COPD verursacht durch Irritanzien am Arbeitsplatz – ein evidenzbasierter Ansatz
No full textWRA is a frequent occupational lung disease in an industrialized environment. It is subdivided into OA and work-aggravated asthma. The main objective of this study was to give an evidence-based overview of the literature on irritative agents, professions or work-sites causing irritant-induced OA and/or occupational COPD.
The key question of this study was: Which respiratory airborne agents cause irritant-induced OA or occupational COPD, and on what level of evidence can such findings be supported?
A database search provided 450 studies dealing with irritant-induced OA or occupational COPD.
An evidence-based approach was realized by applying two suitable grading systems. The modified SIGN grading was used for rating the quality of all considered studies individually. The modified RCGP three-star system was applied for grading each irritant agent with regard to cause irritant-induced OA or occupational COPD. This permitted all study types of different scientific strength.
Irritant-induced OA was the focus of most studies and was the predominant diagnosis. Different ways of confirming irritant-induced OA were used by the author. SIC and lung function tests were the most important diagnostic instruments. Occupational COPD was mainly not the specified target. Some studies described respiratory symptoms such as chronic bronchitis which may be associated with COPD. One of the few studies which focused on occupational COPD was a large retrospective cohort study on diesel exhaust.
According to the SIGN grading system more than half of the publications represent non-scientific studies and were rated with the lowest level, this comprises case reports/case series and occupational disease statistics. The highest level realized by SIGN grading was 2+, which means a well-conducted scientific study with a low risk of confounding or bias. On the basis of the modified RCGP three-star grading, strengths of evidence of the individual/ mixed agent, profession or work-site could be identified. The highest evidence achieved was two stars.
Only a few agents, professions or work-sites were found with moderate evidence level for causing irritant-induced OA or occupational COPD. These include chlorine, welding fumes or construction work (see Table 5, chapter “Results”). For most agents only limited evidence was found, e.g. for acids, acrylates or diesel exhaust (see Table 7, chapter “Results”).
It is possible that not all relevant studies were found in the literature search. Other limitations of this work may be due to the possibility that selection and information bias cannot be totally excluded.
In conclusion, the diagnosis of irritant-induced OA should be especially considered if there has been a single or repeated exposures to high concentration or chronic exposures to moderate (in the TLV ranges) concentrations of an identified irritative agent without evidence of an IgE-mediated pathomechanism.
The diagnosis of occupational COPD should be considered if there have been mainly chronic exposures to an agent capable of causing occupational COPD, not reversible chronic airway disease is found, there is a temporal relationship between the period of exposure and development of COPD, and no other cause of COPD is obviously present.
Based on the estimated population-attributable risk due to occupational exposures for OA and occupational COPD, which are still considerably underreported occupational diseases, strategies designed to prevent these disorders should receive high priority in global efforts to reduce their burden. This study might amplify adequate diagnostic procedures and may help to optimize primary and secondary prevention. Since there is still a lack of knowledge on the causative role of irritant agents and conditions, more research should focus on this issue in order to improve further respective evidence-based diagnostic procedures and preventive strategies
What are the benefits of medical screening and surveillance?
No full textResponse to letter to editor on Wilken D, Baur X, Barbinova L, et al. What are the benefits of medical screening and surveillance?Eur Respir Rev 2012; 21: 105–11
Disputatio Philosophica, exhibens Solis Quietem Et Terrae Motum
No full textQuam ... Praeside ... Dn. Georgio Othone ... Ad diem 23. August. Anno M.DC.XC. ... publice ventilaudam proponit Johan. Wernerus Baur/ Author & RespondensDruck mit allgemein formulierter Widmung "Deo Patriae & Amicis" auf der Rückseite des Titelbl
Human impact on the vegetation of limestone cliffs in the northern Swiss Jura mountains
No full textCliffs provide unique habitats for many specialised organisms, including
chamaephytes and slowly growing trees. Drought, high temperature
amplitude, scarcity of nutrients and high insolation are general characteristics
of exposed limestone cliff faces. The vegetation of limestone cliffs in the
Swiss Jura mountains consists of plants of arctic-alpine, continental and
Mediterranean origin. Several populations exhibit relicts from post- or
interglacial warm or cold climatic periods. Grazing goats and timber
harvesting influenced the forests surrounding the limestone cliffs in northern
Switzerland for many centuries. During the twentieth century, however, these
traditional forms of forest use were abandoned.
In recent years, rock climbing enjoys increasing popularity in mountain
areas at low elevation, where this sport can be performed during the whole
year. The limestone cliffs of the Jura mountains provide unique opportunities
for sport climbers. As a consequence, more than 2000 climbing routes with
fixed protection bolts have been installed on 48 rock cliffs in the region of
Basel, Switzerland.
Overgrowing forest, due to the abandonment of forestry and damages
due to recreational activities including rock climbing reduce the quality and
size of the cliff habitats. In my dissertation, I examined quantitative, spatial
and temporal patterns of human impacts on the cliff flora and on the genetic
population structure of two plant species on isolated cliffs in the Jura
mountains of northern Switzerland.
The assessment of plant cover and species density at various distances
from frequently used climbing routes in the region showed that plant cover
was significantly reduced at the base of climbing routes. Furthermore, species
density (number of species per m2) at the cliff base as well as plant cover and
species density on the cliff face tended to increase with distance from the
route.
The comparison of the vegetation at the cliff base and on the cliff face of
five frequently climbed cliffs with that of seven unclimbed cliffs indicated that
rock climbing significantly altered the plant composition. Specialised rock
species occurred less frequently on climbed cliffs than on unclimbed cliffs.
At the Gerstelflue, a popular recreational climbing site with rock climbing
activities since more than 40 years, plant cover and species density (number
of species per m2) were reduced in climbed areas. Rock climbing also
reduced the density (number of individuals per m2) of forbs and shrubs,
whereas the density of ferns tended to increase in climbed areas. In addition,
rock climbing caused a significant shift in plant species composition and
altered the proportions of different plant life forms.
Species diversity and cover of lichens, and possible associations
between lichens and lichen-feeding land snails were assessed in climbed and
unclimbed areas of 10 isolated cliffs. Total lichen species density was not
correlated with the complexity of the rock surface, climbing frequency and age
of the climbing route. The species density of epilithic lichens was lower along
climbing routes than in unclimbed areas, whereas no difference in species
density of endolithic lichens was found between climbed and unclimbed
areas. Furthermore, climbed and unclimbed areas did not differ in total lichen
cover. The dissimilarity of the lichen communities between climbed and
unclimbed areas increased with increasing climbing intensity on the focal
route in climbed areas, but not with the age of the climbing route. Within cliffs,
plots along climbing routes harboured fewer snail species and individuals than
plots in unclimbed areas.
The effects of forestry practices on the species richness and abundance
of vascular plants on the face, at the base and on the talus have been
investigated by comparing two different forestry practices (clear-cutting and
shelter tree cutting) with forest reserve (i.e. no management in the past 80
years)) on three cliffs. Plant species density and vegetation cover was higher
in the shelter-cut areas than in the forest reserves on the talus as well as at
the cliff base. Clear-cut areas showed a higher vegetation cover than forest
reserves on the talus. Shelter-cut areas harboured a larger proportion of
plants with high light demands and plant indicator species showed a higher
mean light score than in clear-cut areas and forest reserves.
The analysis of time-series of air photographs taken between 1951 and
2000 at six cliffs revealed an increase in tree cover from 60% to 85% between
1951 and 1964 after which the increase levelled off. The increase in tree
cover showed a distinct spatial pattern. It was significant in the talus and on
the cliff face, but not on the plateau (at the top of the cliffs).
Possible effects of isolation and the presumed colonisation history of
cliffs as well as of anthropogenic activities on the genetic population structure
of two plant species with different life-histories were assessed using RAPDpolymorphisms.
Fourteen populations of Draba aizoides L. and 12 populations
of Melica ciliata L. living on isolated limestone cliffs were examined. Analysis
of molecular variance revealed a high among-population variation of each
27% in the gene pools of both species. A clear isolation-by-distance pattern
and a separation of populations from the Jura mountains and the Alps were
found in D. aizoides. This provides evidence for glacial relict endemism in this
species, resulting from nunatak survival in the Jura mountains. In M. ciliata,
UPGMA-analysis showed clusters of plant populations growing on cliffs with
castles with shared historical incidents, indicating zoochorical dispersal
related to human settlements.
The various studies emphasise the uniqueness and vulnerability of the
limestone cliff ecosystem of northern Switzerland. Protection measures in
several fields of activity are needed to preserve the unique relict vascular
plant, lichen and animal communities. Adequate management actions should
be developed and implemented. Actions should particularly be directed to
cliffs with numerous arctic-alpine plant species to protect them from mechanic
disturbances by sport climbing and hiking. The prohibition of sport climbing on
cliffs with a high number of specialised plant or animal species and the
establishment of climbing-free protection zones in popular areas are the most
effective and adequate measures in this context. However, any management
plan should include a comprehensive information campaign to show the
potential impact of intensive sport climbing on the specialised flora and fauna
and to increase the compliance of these measures by the climbers. Forestry
practices that keep the supply of light on a high level at the lower parts of the
cliffs are required to preserve the relict plant species. Selective thinning on the
talus results in relatively large plots with good light conditions and therefore
promotes the rare, relict plant species with high light demands. Self
evidentely, forestry actions and climbing prohibitions should be executed in
coordination. Another measure to manage the lower parts of cliffs could be to
use them as temporal pastures for goats. Finally, the preservation of
mediaeval sites also connotes the conservation of plant species introduced
into the area during the time of human activities
Educators stress and job strain caused by night employment - Results of a questionnaire and a field study
No full textVerbesserung der Latex-Allergie-Diagnostik mittels rekombinanter Allergene
No full textIn Deutschland werden derzeit pro Jahr ca. 200 Anzeigen wegen des Verdachts auf eine latexbedingte Berufskrankheit der Haut oder der Atemwege erstattet. Die Hauttestdiagnostik erfolgt mit nativen Extrakten der Latexmilch. Für die serologische Diagnostik, z.B. mittels CAP, werden bisher natürliche Allergene - z.T. bereits ergänzt durch rekombinantes Hev b 5- eingesetzt. Schwankungen hinsichtlich der Qualität und der Quantität der einzelnen Allergene in den Extrakten und der wenig standardisierten Extraktionsverfahren können zu falsch postitiven oder falsch negativen Befunden führen. Ziel dieser Studie war daher die Etablierung eines sensitiven und spezifischen, auf rekombinaten Latexallergenen basierenden Assays, der eine leichte Standardisierbarkeit und eine Unabhängigkeit von den Naturextrakten ermöglicht.
In der vorliegenden Arbeit haben wir aus Blättern des Gummibaums Hevea brasiliensis die Gesamt-RNA isoliert. Mittels spezifischer Primer wurde anschließend cDNA bekannter Latexallergene über RT-PCR amplifiziert und in den bakteriellen Expressionsvektor pQE30UA kloniert. Die Überprüfung der Identität des Inserts erfolgte anhand von Sequenzierungen. Die Lysate der rekombinanten Latexallergenen-exprimierenden Bakterien wurden im ELISA direkt zur Beschichtung der ELISA-Platten eingesetzt. Lysate der GPDH-exprimierenden Bakterien dienten zur Hintergrunderfassung. Für die CAP-Analytik wurde das rekombinate Latexallergen Hev b 6 über Ni-NTA-Agarose gereinigt, biotinyliert und an Streptavidin-CAPs gekoppelt. Das vorhandene, gut definierte Kollektiv aus 120 Beschäftigten im Gesundheitswesen mit anamnestichen Hinweisen auf eine Latexallergie wurde mittels ELISA und teilweise mittels CAP-Analytik auf spezifische Antikörper (IgE) gegen Latex untersucht. Die Ergebnisse dieser Studie mit den rekombinanten Allergenen bestätigten in verschiedenen Teilkolektiven aus dem Gesundheitswesen im Wesentlichen die bisherigen Ergebnisse in der Literatur, die überwiegend mit nativen Latexallergenen durchgeführt wurden.
Als Minor-Allergene (<50% der Patienten sensibilisiert) wurden rHev b 1, 3, 7 und 8 identifiziert. Dagegen stellen rHev b 5 und 6 Majorallergene dar. Auch das kürzlich bekannt gewordenen Hev b 13 konnte in seiner nativen Form als Major-Allergen identifiziert werden. Im Gegensatz hierzu zeigte das rekombinante Hev b 13 eine wesentlich geringere Allergenität.
Der Einsatz rekombinanter Allergene als Basis für eine verbesserte Diagnostik der Latexallergie vereinfacht die Standardisierung, gewährleistet Unabhängigkeit von den Naturextrakten und macht komplizierte Reinigungsverfahren hinfällig. Rekombinante Allergene ermöglichen darüber hinaus die Durchführung einer am individuellen Sensibilisierungsmuster orientierten spezifischen Immuntherapie, Voraussetzung für derartige Anwendungen ist jedoch, dass die rekombinante Form der Allergene sich immunologisch gleichartig wie die native Form verhält und auch die IgE-Antikörper der Latexallergene binde. Dies lies sich in den vorliegenden Untersuchung für Hev b 1, 3, 5, 6, 7 und 8, nicht jedoch für Hev b 13 belegen
Elliptic boundary value problems and construction of Lp-strong feller processes with singular drift and reflection
No full textBenedict Baur presents modern functional analytic methods for construction and analysis of Feller processes in general and diffusion processes in particular. Topics covered are: Construction of Lp-strong Feller processes using Dirichlet form methods, regularity for solutions of elliptic boundary value problems, construction of elliptic diffusions with singular drift and reflection, Skorokhod decomposition and applications to Mathematical Physics like finite particle systems with singular interaction. Emphasize is placed on the handling of singular drift coefficients, as well as on the discussion of pointwise and pathwise properties of the constructed processes rather than just the quasi-everywhere properties commonly known from the general Dirichlet form theory. Contents Construction of Lp-Strong Feller Processes Elliptic Boundary Value Problems Skorokhod Decomposition for Reflected Diffusions with Singular Drift Particle Systems with singular interaction Target Groups Graduate and PhD students, researchers of Mathematics in the field (Functional) Analysis, Stochastics, Partial Differential Equations and Mathematical Physics The Author Benedict Baur has done his doctor’s degree at the University of Kaiserslautern in topics on Stochastics and Functional Analysis.
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