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13 records – page 1 of 2.

137Cs concentrations in lichens before and after the Chernobyl accident

https://arctichealth.org/en/permalink/ahliterature102073
Source
Health Physics. 1993 Jan;64(1):70-73
Publication Type
Article
Date
Jan-1993
Author
Hofmann, W
Attarpour, N
Lettner, H
Türk, R
Source
Health Physics. 1993 Jan;64(1):70-73
Date
Jan-1993
Language
English
Publication Type
Article
Keywords
Accidents
Austria
Cesium Radioisotopes--analysis
Lichens--chemistry
Nuclear Reactors
Radioactive Fallout--analysis
Ukraine
Abstract
137Cs activities were measured in a variety of epigeic and epiphytic lichens in Austria before and after contamination by the Chernobyl fallout. For comparison, the activity of the naturally occurring 40K was also determined in each lichen sample. The high 137Cs activities found after Chernobyl suggest that lichens are suitable and inexpensive biological detectors of the fallout pattern.
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Adaptogenic activity of a complex biomedication based on a northern renewable raw material.

https://arctichealth.org/en/permalink/ahliterature273839
Source
Wiad Lek. 2016;69(1 Pt 2):55-60
Publication Type
Article
Date
2016
Author
Vera V Anshakova
Albina V Stepanova
Dimitrii M Uvarov
Aigerim Sh Smagulova
Ksenia N Naumova
Petr P Vasiliev
Source
Wiad Lek. 2016;69(1 Pt 2):55-60
Date
2016
Language
English
Publication Type
Article
Keywords
Animals
Biological Availability
Exercise - physiology
Humans
Lichens - chemistry
Mice
Phytotherapy
Plant Extracts - pharmacokinetics
Rhodiola - chemistry
Russia
Swimming - physiology
Abstract
One of the methods of increasing bioavailability, and thus the therapeutic effectiveness of an active substances, along with decreasing its required dosage, is to generate highly effective "carrier: active substances" complexes where the active carrier both increases the bioavailability of the active substance at lower doses and has a detoxifying activity.
the aim of this work was study the properties of the carrier from the lichen thallome in both its solid pharmaceutical form and in combination with Rhodiola rosea.
the physiologically active plant extracts with enhanced adaptogenic pharmacological activity based on plant substances growing in Yakutia: Cladonia lichen thalli and Rhodiola rosea (Rhodiolarosea, fam.Crassulaceae) rhizomes, combined in a raw material dry-weight ratio of 10:1 We used a one step, solvent-free process, involving the use of mechanochemical ball mills relying on centrifugal acceleration of the 10-30 g grinding bodies.
A single-stage mechanochemical technology has been developed for obtaining highly effective solid-phase biocomplexes based on a"multipurpose active filler" - a polymer matrix of lichen ?-oligosaccharides. It has been shown that lichen, is a raw material from which can be sourced a filler with a strong adsorption activity for solid pharmaceutical forms.
It is considered statistically significant that a bicomponent plant mechanocomplex based on this filler - lichen ?-oligosaccharides and small amounts of Rhodiola rosea has a wide spectrum of adaptogenic action, increasing the resistance of laboratory animals to the effects of physical exercise and a variety of extreme factors.
PubMed ID
27164277 View in PubMed
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Application of short-lived radionuclides in neutron activation analysis of biological and environmental samples.

https://arctichealth.org/en/permalink/ahliterature219543
Source
Biol Trace Elem Res. 1994;43-45:33-46
Publication Type
Article
Date
1994
Author
F. Grass
M. Bichler
J. Dorner
H. Holzner
A. Ritschel
A. Ramadan
G P Westphal
R. Gwozdz
Author Affiliation
Atominstitut, Vienna, Austria.
Source
Biol Trace Elem Res. 1994;43-45:33-46
Date
1994
Language
English
Publication Type
Article
Keywords
Animal Feed - analysis
Environmental pollution - analysis
Half-Life
Humans
Iodine - analysis
Lichens - chemistry
Lithium - analysis
Neutron Activation Analysis - methods
Norway
Radioisotopes
Scandium - analysis
Seawater - analysis
Selenium Radioisotopes - analysis
Water Pollutants, Chemical - analysis
Abstract
The application of short-lived nuclides, especially in connection with the 6LiD-converter, in biological and environmental samples is demonstrated on I and Br determination in human urine, on I in pet food, and on the analysis of all the halogens in volcanic gases in a single activation. Trace element determination in lichens indicates polluted and unpolluted areas. The use of the .74-s 38mCl enables the rapid screening of great number of samples.
PubMed ID
7710845 View in PubMed
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Averted doses to Norwegian Sámi reindeer herders after the Chernobyl accident.

https://arctichealth.org/en/permalink/ahliterature128222
Source
Health Phys. 2012 Feb;102(2):208-16
Publication Type
Article
Date
Feb-2012
Author
Lavrans Skuterud
Håvard Thørring
Author Affiliation
Norwegian Radiation Protection Authority, PO Box 55, NO-1332 Østerås, Norway. Lavrans.Skuterud@nrpa.no
Source
Health Phys. 2012 Feb;102(2):208-16
Date
Feb-2012
Language
English
Publication Type
Article
Keywords
Animal Husbandry
Animals
Cesium Radioisotopes - analysis
Chernobyl Nuclear Accident
Food contamination, radioactive
Humans
Lichens - chemistry
Meat
Norway
Radiation Dosage
Reindeer
Whole-Body Counting
Abstract
The Chernobyl fallout is an enduring challenge to reindeer husbandry in Norway, and South Sámi reindeer herders in central and southern Norway are as contaminated by (137)Cs as inhabitants close to Chernobyl. Therefore, Norwegian authorities continuously recommend to these reindeer herders the use of countermeasures to reduce their intake of (137)Cs. In this study, the authors have applied data on contamination levels in reindeer, results of dietary surveys, and whole body monitoring data in low and high contaminated areas to estimate the effectiveness of countermeasures and resulting averted doses to the reindeer herders. In the most contaminated area, the various countermeasures applied reduced radiocesium ingestion doses during 1986-2009 by about 73%, to an integrated dose of about 17 mSv. However, to comply with the recommended (137)Cs ingestion dose limit of 1 mSv y(-1), the study indicates that reindeer herders in the most contaminated areas will need to carry on with their countermeasures for another 10-15 y. Furthermore, the study indicates that whole body monitoring is an important tool to assess individual doses and countermeasure effectiveness in long-term management of a contamination situation and that such monitoring may be required to reach long-term reference levels.
PubMed ID
22217593 View in PubMed
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Distribution of radionuclides in moss-lichen cover and needles on the same grounds of landscape-climatic zones of Siberia.

https://arctichealth.org/en/permalink/ahliterature297819
Source
J Environ Radioact. 2019 Mar; 198:64-78
Publication Type
Journal Article
Date
Mar-2019
Author
I N Malikova
V D Strakhovenko
B L Shcherbov
Author Affiliation
Sobolev Institute of Geology and Mineralogy SB RAS, Acad. Koptyug Ave. 3, Novosibirsk, 630090, Russia. Electronic address: michurina@igm.nsc.ru.
Source
J Environ Radioact. 2019 Mar; 198:64-78
Date
Mar-2019
Language
English
Publication Type
Journal Article
Keywords
Air Pollutants, Radioactive - analysis
Bryophyta - chemistry
Cesium radioisotopes
Coniferophyta
Forests
Lichens - chemistry
Plant Leaves - chemistry
Radiation Monitoring - methods
Siberia
Soil
Soil Pollutants, Radioactive - analysis
Thorium
Uranium
Abstract
The radiation status of the landscape and climatic zones of Siberia at the turn of the 20th and 21st centuries is characterized using bioindicators/biomonitors: lichens, mosses, and needles, according to the results obtained at the sites of their joint growth. The maximal activity of 137Cs in these components is observed in the forest-tundra landscaped zone, polluted during the period of nuclear tests from the nuclear test site "Novaya Zemlya" and also due to slow migration of these elements to the soil under the arctic conditions. In the southern territories the specific activity of radiocesium in the moss-lichen cover and needles of conifers corresponds to the regional background, in the forest-tundra zone it sometimes exceeds it, but in general does not pose a threat to human health. Determined differences in the contents of radioactive elements in lichens and mosses that grow together on sites in different landscape zones of Siberia statistically not significant within one or two standard deviations, and recorded only in the range of 3? at the level of significance 0.05. Specificity of radionuclide distribution in lichens, mosses and needles (differences for epigeals and epiphytic lichens; different species selected at one site, annual and perennial needles, etc.) made it possible to identify the causes of variations in their activities in different zones, along with landscape features of these zones. In the needles of conifers potassium concentration exceeds the content in lichens, at lower levels of thorium and 137Cs. The contents of uranium and thorium in the studied components in all landscape-climatic zones correspond to the natural ones, except for the single local territories, because of the possible anthropogenic influence.
PubMed ID
30592996 View in PubMed
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Experimental warming alters migratory caribou forage quality.

https://arctichealth.org/en/permalink/ahliterature302067
Source
Ecol Appl. 2017 10; 27(7):2061-2073
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
10-2017
Author
Tara J Zamin
Steeve D Côté
Jean-Pierre Tremblay
Paul Grogan
Author Affiliation
Department of Biology, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
Source
Ecol Appl. 2017 10; 27(7):2061-2073
Date
10-2017
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Arctic Regions
Food Quality
Global warming
Lichens - chemistry - growth & development
Magnoliopsida - chemistry - growth & development
Northwest Territories
Nutrients - chemistry
Reindeer - physiology
Seasons
Species Specificity
Tundra
Abstract
Global declines in caribou and reindeer (Rangifer) populations have drawn attention to the myriad of stressors that these Arctic and boreal forest herbivores currently face. Arctic warming has resulted in increased tundra shrub growth and therefore Rangifer forage quantity. However, its effects on forage quality have not yet been addressed although they may be critical to Rangifer body condition and fecundity. We investigated the impact of 8 yrs of summer warming on the quality of forage available to the Bathurst caribou herd using experimental greenhouses (n = 5) located in mesic birch hummock tundra in the central Canadian Low Arctic. Leaf forage quality and digestibility characteristics associated with nutrients (nitrogen and phosphorus), phenolics, and fiber were measured on the deciduous shrub Betula glandulosa (an important Rangifer diet component) at six time points through the growing season, and on five other very common vascular plant and lichen species in late summer. Experimental warming reduced B. glandulosa leaf nitrogen concentrations by ~10% in both late June and mid-July, but not afterwards. It also reduced late summer forage quality of the graminoid Eriophorum vaginatum by increasing phenolic concentrations 38%. Warming had mixed effects on forage quality of the lichen Cetraria cucullata in that it increased nutrient concentrations and tended to decrease fiber contents, but it also increased phenolics. Altogether, these warming-induced changes in forage quality over the growing season, and response differences among species, highlight the importance of Rangifer adaptability in diet selection. Furthermore, the early season reduction in B. glandulosa nitrogen content is a particular concern given the importance of this time for calf growth. Overall, our demonstration of the potential for significant warming impacts on forage quality at critical times for these animals underscores the importance of effective Rangifer range conservation to ensure sufficient appropriate habitat to support adaptability in forage selection in a rapidly changing environment.
PubMed ID
28653471 View in PubMed
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Immunologically active (1-->3)-(1-->4)-alpha-D-glucan from Cetraria islandica.

https://arctichealth.org/en/permalink/ahliterature10679
Source
Phytomedicine. 1999 Mar;6(1):33-9
Publication Type
Article
Date
Mar-1999
Author
E S Olafsdottir
K. Ingolfsdottir
H. Barsett
B S Paulsen
K. Jurcic
H. Wagner
Author Affiliation
Department of Pharmacy, University of Iceland, Reykjavik, Iceland. elinsol@rhi.hi.is
Source
Phytomedicine. 1999 Mar;6(1):33-9
Date
Mar-1999
Language
English
Publication Type
Article
Keywords
Adjuvants, Immunologic - isolation & purification - pharmacology
Carbohydrates - analysis
Chromatography, Gel
Chromatography, Ion Exchange
Chromatography, Thin Layer
Complement Inactivator Proteins - pharmacology
Glucans - isolation & purification - pharmacology
Humans
In Vitro
Lichens - chemistry
Methanol
Methylation
Phagocytosis - drug effects
Research Support, Non-U.S. Gov't
Abstract
A polysaccharide, Ci-3, resembling isolichenan except with a much higher degree of polymerization, has been isolated from the water extract, as well as from the alkali extract, of the lichen Cetraria islandica (L.) using ethanol fractionation, dialysis, ion-exchange chromatography and gel filtration. The mean M(r) of Ci-3 was determined to be 2000 kD, compared to 6-8 kD reported for isolichenan. The structure of Ci-3 was elucidated and found to be composed of (1-->3)- and (1-->4)-alpha-D-glucopyranosyl units in the ratio of 2:1, using methanolysis, methylation analysis, optical rotation and NMR spectroscopy. The immunomodulating activity of Ci-3 was tested in an in vitro phagocytosis assay and anti-complementary, and proved to be active in both tests.
PubMed ID
10228609 View in PubMed
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In vitro and in vivo immunomodulating effects of traditionally prepared extract and purified compounds from Cetraria islandica.

https://arctichealth.org/en/permalink/ahliterature87237
Source
Int Immunopharmacol. 2008 Mar;8(3):423-30
Publication Type
Article
Date
Mar-2008
Author
Freysdottir J.
Omarsdottir S.
Ingólfsdóttir K.
Vikingsson A.
Olafsdottir E S
Author Affiliation
Centre for Rheumatology Research, Landspitali University Hospital, IS-101 Reykjavik, Iceland; Department of Immunology, Landspitali University Hospital, IS-101 Reykjavik, Iceland. jonaf@landspitali.is
Source
Int Immunopharmacol. 2008 Mar;8(3):423-30
Date
Mar-2008
Language
English
Publication Type
Article
Keywords
Animals
Arthritis, Experimental - drug therapy
Dendritic Cells - drug effects - physiology
Female
Humans
Immunologic Factors - pharmacology
Interleukin-10 - biosynthesis
Interleukin-12 Subunit p40 - biosynthesis
Lichens - chemistry
Medicine, Traditional
Molecular Weight
Polysaccharides - pharmacology
Rats
Rats, Inbred Lew
Abstract
Cetraria islandica (Iceland moss) has been used for centuries in folk medicine in many countries against a number of conditions, including inflammatory conditions, mainly as an aqueous extract. C. islandica contains many compounds, such as polysaccharides and secondary metabolites, some of which have established biological activity. However, very little is known about their effect on the immune system. Human monocyte-derived immature dendritic cells were cultured with an aqueous extract from C. islandica quantified with regard to the polysaccharides lichenan and isolichenan and secondary metabolites protolichesterinic and fumarprotocetraric acids. The purified compounds were also tested individually. Their effect on the maturation of the dendritic cells was assessed by measuring secretion of IL-10 and IL-12p40 and expression of surface molecules. In addition, the effect of the aqueous extract on antigen-induced arthritis in rats was investigated. The aqueous extract caused upregulated secretion of both IL-10 and IL-12p40, with IL-10 secretion being more prominent. Lichenan had similar effects, whereas isolichenan and the secondary metabolites were inactive, suggesting that the effect observed by the aqueous extract was mainly mediated by lichenan. Significantly less arthritis was observed for rats treated by the aqueous extract, administered subcutaneously, compared with rats treated with saline alone. These results suggest that the aqueous extract of C. islandica has anti-inflammatory effect, possibly by changing the cytokine secretion bias from IL-12p40 towards IL-10.
PubMed ID
18279796 View in PubMed
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Mercury in tundra vegetation of Alaska: Spatial and temporal dynamics and stable isotope patterns.

https://arctichealth.org/en/permalink/ahliterature299087
Source
Sci Total Environ. 2019 Apr 10; 660:1502-1512
Publication Type
Journal Article
Date
Apr-10-2019
Author
Christine L Olson
Martin Jiskra
Jeroen E Sonke
Daniel Obrist
Author Affiliation
Division of Atmospheric Sciences, Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512, USA.
Source
Sci Total Environ. 2019 Apr 10; 660:1502-1512
Date
Apr-10-2019
Language
English
Publication Type
Journal Article
Keywords
Alaska
Climate change
Lichens - chemistry
Mercury - analysis - chemistry
Mercury Isotopes - analysis - chemistry
Soil Pollutants - analysis
Tundra
Abstract
Vegetation uptake of atmospheric mercury (Hg) is an important mechanism enhancing atmospheric Hg deposition via litterfall and senescence. We here report Hg concentrations and pool sizes of different plant functional groups and plant species across nine tundra sites in northern Alaska. Significant spatial differences were observed in bulk vegetation Hg concentrations at Toolik Field station (52?±?9?µg?kg-1), Eight Mile Lake Observatory (40?±?0.2?µg?kg-1), and seven sites along a transect from Toolik Field station to the Arctic coast (36?±?9?µg?kg-1). Hg concentrations in non-vascular vegetation including feather and peat moss (58?±?6?µg?kg-1 and 34?±?2?µg?kg-1, respectively) and brown and white lichen (41?±?2?µg?kg-1 and 34?±?2?µg?kg-1, respectively), were three to six times those of vascular plant tissues (8?±?1?µg?kg-1 in dwarf birch leaves and 9?±?1?µg?kg-1 in tussock grass). A high representation of nonvascular vegetation in aboveground biomass resulted in substantial Hg mass contained in tundra aboveground vegetation (29?µg?m-2), which fell within the range of foliar Hg mass estimated for forests in the United States (15 to 45?µg?m-2) in spite of much shorter growing seasons. Hg stable isotope signatures of different plant species showed that atmospheric Hg(0) was the dominant source of Hg to tundra vegetation. Mass-dependent isotope signatures (d202Hg) in vegetation relative to atmospheric Hg(0) showed pronounced shifts towards lower values, consistent with previously reported isotopic fractionation during foliar uptake of Hg(0). Mass-independent isotope signatures (?199Hg) of lichen were more positive relative to atmospheric Hg(0), indicating either photochemical reduction of Hg(II) or contributions of inorganic Hg(II) from atmospheric deposition and/or dust. ?199Hg and ?200Hg values in vascular plant species were similar to atmospheric Hg(0) suggesting that overall photochemical reduction and subsequent re-emission was relatively insignificant in these tundra ecosystems, in agreement with previous Hg(0) ecosystem flux measurements.
PubMed ID
30743942 View in PubMed
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Pb isotopes as tracers of mining-related Pb in lichens, seaweed and mussels near a former Pb-Zn mine in West Greenland.

https://arctichealth.org/en/permalink/ahliterature98128
Source
Environ Pollut. 2010 May;158(5):1319-26
Publication Type
Article
Date
May-2010
Author
Jens Søndergaard
Gert Asmund
Poul Johansen
Bo Elberling
Author Affiliation
Department of Arctic Environment, National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, DK-4000 Roskilde, Denmark. jens@dmu.dk
Source
Environ Pollut. 2010 May;158(5):1319-26
Date
May-2010
Language
English
Publication Type
Article
Keywords
Animals
Bivalvia - chemistry
Environmental Monitoring - methods
Environmental Pollutants - analysis
Greenland
Isotopes - analysis
Lead - analysis
Lichens - chemistry
Mining
Seaweed - chemistry
Abstract
Identification of mining-related contaminants is important in order to assess the spreading of contaminants from mining as well as for site remediation purposes. This study focuses on lead (Pb) contamination in biota near the abandoned 'Black Angel Mine' in West Greenland in the period 1988-2008. Stable Pb isotope ratios and total Pb concentrations were determined in lichens, seaweed and mussels as well as in marine sediments. The results show that natural background Pb ((207)Pb/(206)Pb: 0.704-0.767) and Pb originating from the mine ore ((207)Pb/(206)Pb: 0.955) have distinct isotopic fingerprints. Total Pb in lichens, seaweed, and mussels was measured at values up to 633, 19 and 1536 mg kg(-1) dry weight, respectively, and is shown to be a mixture of natural Pb and ore-Pb. This enables quantification of mining-related Pb and shows that application of Pb isotope data is a valuable tool for monitoring mining pollution.
PubMed ID
20138695 View in PubMed
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13 records – page 1 of 2.