This paper concerns the use of Terrestrial Laser Scanning (TLS) methods and the Geographic Information Systems (GIS) analysis to determine microtopography of a natural river valley, case study of the upper Biebrza valley. The scientific problem analyzed in this paper is a morphology of the selected segments of the valley covered by sedge ecosystems which in natural stage form a characteristic tussocks from their root systems. In order to capture the microtopography it was necessary to remove vegetation from the selected areas, and then, for a five typical location, registration of its structure using the laser scanner. As a result the point cloud was generated for each of the selected area and after GIS analysis the microtopography was obtained in form of digital terrain model (DTM). The DTM of each area represents valleys microstructure possible to obtain by use of TLS (TLS DTM), is usually not registered by the Airborne Laser Scanning (ALS), and is the main reason of inaccuracy of the DTM obtained based on ALS. The resulting TLS DTM has been processed by various filtering methods to lower the noise and fi ll the voids from blocking the laser beam by a tussocks. Finally, this allowed to determine the spatial structure of each measurement field.
Metallo-beta-lactamases (MBLs) produced by Pseudomonas aeruginosa are a serious threat due to their ability to be transmitted between the same as well as different bacterial species. Different methods are applied in the clinical laboratory to detect MBLs. The aim of this study was to compare 4 phenotypic methods and a PCR assay for their ability to detect MBLs in clinical isolates of carbapenem-resistant P. aeruginosa strains. The study embraced a total of 70 carbapenem-resistant P. aeruginosa strains isolated in The Department of Microbiology of Dr A. Jurasz University Hospital in Bydgoszcz. The highest percentage (42.9%) of the strains were isolated from Intensive Care Unit patients, mainly from urine samples (31.4%). Methods used in this study were: double-disc synergy tests in two combinations: using ceftazidime with 2-mercaptopropionic acid and imipenem with EDTA, differences in inhibition zone diameters between discs with imipenem/ EDTA and imipenem, Etest MBL (AB Biodisk) and molecular amplification of blaIMP and blaVIM blaym genes responsible for producing MBLs, using PCR assay. The lowest percentage (1.4%) of positive results in detection of MBLs was obtained using PCR assay, the highest (72.9%) by double-disc synergy tests with imipenem and EDTA, but the specificity of this method may be low.
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It is well documented that reactive oxygen species (ROS) are involved in the aetiology of age related diseases. Over the last decades, strong efforts have been made to identify antioxidants in human foods and numerous promising compounds have been detected which are used for the production of supplements and functional foods. The present paper describes the advantages and limitations of methods which are currently used for the identification of antioxidants. Numerous in vitro methods are available which are easy to perform and largely used in screening trials. However, the results of such tests are only partly relevant for humans as certain active compounds (e.g. those with large molecular configuration) are only poorly absorbed in the gastrointestinal tract and/or may undergo metabolic degradation. Therefore experimental models are required which provide information if protective effects take place in humans under realistic conditions. Over the last years, several methods have been developed which are increasingly used in human intervention trials. The most widely used techniques are chemical determinations of oxidised guanosine in peripheral blood cells or urine and single cell gel electrophoresis (comet) assays with lymphocytes which are based on the measurement of DNA migration in an electric field. By using of DNA-restriction enzymes (formamidopyrimidine DNA glycosylase and endonuclease III) it is possible to monitor the endogenous formation of oxidised purines and pyrimidines; recently also protocols have been developed which enable to monitor alterations in the repair of oxidised DNA. Alternatively, also the frequency of micronucleated cells can be monitored with the cytokinesis block method in peripheral human blood cells before and after intervention with putative antioxidants. To obtain information on alterations of the sensitivity towards oxidative damage, the cells can be treated ex vivo with ROS (H2O2 exposure, radiation). The evaluation of currently available human studies shows that in approximately half of them protective effects of dietary factors towards oxidative DNA-damage were observed. Earlier studies focused predominantly on the effects of vitamins (A, C, E) and carotenoids, more recently also the effects of fruit juices (from grapes, kiwi) and beverages (soy milk, tea, coffee), vegetables (tomato products, berries, Brussels sprouts) and other components of the human diet (coenzyme Q10, polyunsaturated fatty acids) were investigated. On the basis of the results of these studies it was possible to identify dietary compounds which are highly active (e.g. gallic acid). At present, strong efforts are made to elucidate whether the different parameters of oxidative DNA-damage correlates with life span, cancer and other age related diseases. The new techniques are highly useful tools which provide valuable information if dietary components cause antioxidant effects in humans and can be used to identify individual protective compounds and also to develop nutritional strategies to reduce the adverse health effects of ROS.
The nested PCR has been used to evaluate the usefulness and efficiency of different Bacillus anthracis spore isolation methods in contaminated soil samples. The best results were obtained using two methods described by Beyer et al. [1] and Cheun et al. [9]. Outer and inner pairs of primers were designed from the protective antigen gene of plasmid pXO1 as well as from genes B and C of the capsule region of the plasmid pXO2. The influence of soil types on obtained results was also studied. The type of soil samples did not affect the nested PCR results. Furthermore, the sensitivity of nested PCR and PCR – ELISA was also examined.
Marten species are usually surveyed by trapping, snow tracking or cameratrapping with baits on trees. While testing the efficiency of a monitoring scheme for wildcats Felis silvestris silvestris in north-western Switzerland, we noticed that martens are attracted by lure sticks scented with valerian. On these sticks, the animals leaved some hairs that allowed us to identify the genus Martes by microscopic analysis. Additionally, the animal can be identified on pictures made by a camera trap posed close to the lure stick. In this paper, we compared the efficiency of different methods to find the most appropriate one in order to survey the pine marten Martes martes (Linnaeus, 1758) in Switzerland. For the method of valerian lure sticks we estimated a detectability of 0.08 per 14 days during the whole year. The detectability raised, when we applied American Hawbaker’s marten lure instead of the valerian tincture. In addition, the detectability was higher during the period April to June (p=0.2) compared to the whole year. If we identified the pine marten on the lure stick with pictures from the camera traps we reached a detectability of 0.21 during the whole year. Using only camera traps with baits on trees we could not take any picture of a pine marten.
The aim of the study was the identification and quantitative analysis of phenylpropanoid compounds in the roots of Rhodiola species. Rosavin, rosarin and rosin were determined in the roots of R. kirilowii and R. rosea from the field cultivation, Institute of Natural Fibres and Medicinal Plants. For the quantitative analysis, the ultra performance liquid chromatography - tandem mass spectrometry (UPLC-ESI MS/MS, Waters) was used. The results showed differences in the quantitative and qualitative assessments of these two species. In the root of R. kirilowii the presence of phenylpropanoids was not confirmed. In R. rosea the most common phenylpropanoid was rosavin (0.022%). The UPLC-MS/MS studies allowed to use this analytical method for determination of phenylpropanoids in the accordance with the requirements of ICH.
An improved liquid chromatography-fluorescence detection method for the determination of seven sulfonamides in bee honey was proposed. The method is selective and robust enough for the required purposes. The whole procedure was validated in accordance with the Commission Decision 657/2002/EC. Detection capabilities were from 26.15 to 49.50 µg/kg, and recoveries ranged from 32.8% to 116.1%, depending on the analyte.
Xenoestrogens are defined as chemicals that mimic some structural parts of the physiological estrogen compounds, therefore may act as estrogens or could interfere with the actions of endogenous estrogens. Two subtypes of the ER are known, the ERcc and ER ß, and both have a distinct tissue distribution and play a distinct role in physiology. Receptor dimmer assumes a distinctive conformation, binds to its estrogen response element (ERE), interacts with the general transcription complex bound to the TATA box within the respective gene promoter, and regulates gene transcription. The discovery and identification of co-activators and co-repressors provided crucial insights into the ER action. New evidence indicates that the activation of additional transcription factors as well as the action of xenoestrogens through estrogen receptors located outside the cell nucleus (in the plasma membrane, mitochondria and probably the cytosol) should be considered. The levels of exposition to xenoestrogens and the age of the investigated animal can have a significant effect on its development and reproduction. Therefore, several in vivo and in vitro assays have been developed to assess the estrogenic-like activity of individual compounds or natural mixtures. In this review, selected methods applied in physiological studies have been described. One of the most extensively used in vivo assays for estrogenicity is the rodent uterotrophic assay. In order to analyze the estrogenic properties of xenoestrogens, morphological, histological, biochemical and molecular studies should be introduced. A variety of in vitro tests have been established to determine estrogenic potency of xenoestrogens but even a combination of them is not able to predict their actual action in the organism. There is a need for the studies on all potential xenoestrogens to describe tissue-specific activities, and via which pathways in those tissues these compounds either disrupt or mimic hormone action.