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1.
Int J Mol Sci ; 24(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36835509

RESUMO

Malassezia spp. are dimorphic, lipophilic fungi that are part of the normal human cutaneous commensal microbiome. However, under adverse conditions, these fungi can be involved in various cutaneous diseases. In this study, we analysed the effect of ultra-weak fractal electromagnetic (uwf-EMF) field exposure (12.6 nT covering 0.5 to 20 kHz) on the growth dynamics and invasiveness of M. furfur. The ability to modulate inflammation and innate immunity in normal human keratinocytes was also investigated. Using a microbiological assay, it was possible to demonstrate that, under the influence of uwf-EMF, the invasiveness of M. furfur was drastically reduced (d = 2.456, p < 0.001), while at the same time, its growth dynamic after 72 h having been in contact with HaCaT cells both without (d = 0.211, p = 0.390) and with (d = 0.118, p = 0.438) uwf-EM exposure, were hardly affected. Real-time PCR analysis demonstrated that a uwf-EMF exposure is able to modulate human-ß-defensin-2 (hBD-2) in treated keratinocytes and at the same time reduce the expression of proinflammatory cytokines in human keratinocytes. The findings suggest that the underlying principle of action is hormetic in nature and that this method might be an adjunctive therapeutic tool to modulate the inflammatory properties of Malassezia in related cutaneous diseases. The underlying principle of action becomes understandable by means of quantum electrodynamics (QED). Given that living systems consist mainly of water and within the framework of QED, this water, as a biphasic system, provides the basis for electromagnetic coupling. The oscillatory properties of water dipoles modulated by weak electromagnetic stimuli not only affect biochemical processes, but also pave the way for a more general understanding of the observed nonthermal effects in biota.


Assuntos
Malassezia , Humanos , Fractais , Pele , Queratinócitos/metabolismo , Fenômenos Eletromagnéticos
2.
J Environ Radioact ; 259-260: 107102, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36657357

RESUMO

Alpine regions in the federal state of Salzburg (Austria) have been intensively contaminated by Chernobyl fallout, necessitating long-term monitoring programs. The sites predominately affected are those in areas with soil developed on silicate bedrock, as these soils tend to be acidic, favouring high transfer factors for 137Cs. In addition, nutrient deficiency, low mineral and high organic matter content, and tough climatic conditions are causing the slow migration of 137Cs in the soil, which are associated with long effective half-lives in the biosphere. As a quantitative measure for effective half-lives, milk has been collected at nine alpine seasonal stock farming sites since 1988; at four sites, the monitoring is still ongoing (2020). For the period between 1999 and 2020, the decrease of 137Cs can be reasonably fitted with one effective half-life describing the time-trend. The effective half-lives obtained by this procedure vary between 9.3 ± 0.9 years and 18.8 ± 3.4 years. The effective half-lives show a weak negative correlation with the half-value depth of 137Cs, defined as the depth of the upper soil layer containing half of the deposited fallout inventory. The majority of the inventory is bound in the rooting zone of 0-10 cm, which is reflected by the small half value depths in the range between 3.2 and 4.4 cm. The soils investigated are acidic with pH values between 3.78 and 4.88, showing a pronounced negative correlation with the effective half-lives of 137Cs in milk. The data indicate that in these soils rich in organic matter, which are also almost totally devoid of clay minerals and have a very low clay size fraction, pH may be the dominating factor influencing the effective half-lives of 137Cs plant uptake and the subsequent contamination of milk.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Animais , Ecossistema , Argila , Leite/química , Poluentes Radioativos do Solo/análise , Radioisótopos de Césio/análise , Solo/química
3.
J Environ Radioact ; 256: 107038, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36345091

RESUMO

In 2019 and 2020, the layers - down to a maximum depth of 30 cm - of 43 soil samples from different regions in Austria were measured gamma-spectrometrically to determine their activity concentration (in Bq/kg and Bq/m³) of 234Th, 214Pb, 214Bi, 210Pb, 228Ac and 40K. 137Cs activity concentration (in Bq/m³) will be found in the supplementary data file only. A basic statistical analysis was carried out and explained variances for distinctions primarily between meadows and forests. Ternary diagrams were applied to represent equilibrium status of inventories and layer activities between 238U-equivalent, 226Ra-equivalent and 210Pb. A method using ternary diagrams for identifying of element-specific dampening effects in remote sensing is presented in the report (ternary "adjustment" diagrams). The tendencies between forest and meadows sites are heterogeneous, but distinctions between coniferous and deciduous forest are extremely likely. Geological settings dominate the distributions, slightly altered by anthropogenic influence, which includes the kind of vegetation. Focusing on top soil layers (first and/or second layer) facilitates discrimination according to vegetation. At some sites changes of activities in the grass root layer (at 15 cm) were observed.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Solo , Áustria , Chumbo/análise , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-34682614

RESUMO

Three therapeutic applications are presently prescribed in the radon spas in Gastein, Austria: exposure to radon in a thermal bath, exposure to radon vapor in an exposure chamber (vapor bath), and exposure to radon in the thermal gallery, a former mine. The radiological exposure pathways to human organs and tissues in these therapeutic radon applications are inhalation of radon and radon progeny via the lungs, radon transfer from water or air through the skin, and radon-progeny deposition on the skin in water or air. The objectives of the present study were to calculate radon and radon-progeny doses for selected organs and tissues for the different exposure pathways and therapeutic applications. Doses incurred in red bone marrow, liver, kidneys, and Langerhans cells in the skin may be correlated with potential therapeutic benefits, while doses to the lungs and the basal cells of the skin indicate potential carcinogenic effects. The highest organ doses among the three therapeutic applications were produced in the thermal gallery by radon progeny via inhalation, with lung doses of 5.0 mSv, and attachment to the skin, with skin doses of 4.4 mSv, while the radon contribution was less significant. For comparison, the primary exposure pathways in the thermal bath are the radon uptake through the skin, with lung doses of 334 µSv, and the radon-progeny attachment to the skin, with skin doses of 216 µSv, while the inhalation route can safely be neglected.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Humanos , Doses de Radiação , Radiometria , Radônio/análise , Radônio/toxicidade , Produtos de Decaimento de Radônio/análise
5.
Radiat Prot Dosimetry ; 177(1-2): 78-82, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036570

RESUMO

In the Gastein valley, numerous facilities use radon for the treatment of various diseases either by exposure to radon in air or in radon rich thermal water. In this study, six test persons were exposed to radon thermal water in a bathtub and the time-dependent radon activity concentration in the exhaled air was recorded. At temperatures between 38°C and 40°C, the radon activity concentration in the water was about 900 kBq/m3 in a total volume of 600 l, where the patients were exposed for 20 min, while continuously sampling the exhaled air during the bathing and 20 min thereafter. After entering the bath, the exhaled radon activity concentration rapidly increased, reaching some kind of saturation after 20 min exposure. The radon activity concentration in the exhaled air was about 8000 Bq/m3 at the maximum, with higher concentrations for male test persons. The total radon transfer from water to the exhaled air was between 480 and 1000 Bq, which is equivalent to 0.08% and 0.2% of the radon in the water.


Assuntos
Poluentes Radioativos do Ar/análise , Banhos , Monitoramento de Radiação/métodos , Radônio/análise , Radônio/uso terapêutico , Adulto , Expiração , Feminino , Humanos , Masculino , Poluentes Radioativos da Água/análise
6.
J Biomed Opt ; 19(8): 085007, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25117078

RESUMO

Photodynamic therapy (PDT) and photodiagnosis based on the intracellular production of the photosensitizer protoporphyrin IX (PPIX) by administration of its metabolic precursor -aminolevulinic acid (ALA) achieved their breakthrough upon the clinical approval of MAL (ALA methyl ester) and HAL (ALA hexyl ester). For newly developed ALA derivatives or application in new tumor types, in vitro determination of PPIX formation involves multiparametric experiments covering variable pro-drug concentrations, medium composition, time points of analysis, and cell type(s). This study uses a fluorescence microplate reader with a built-in temperature and atmosphere control to investigate the high-resolution long-term kinetics (72 h) of cellular PPIX fueled by administration of either ALA, MAL, or HAL for each 10 different concentrations. For simultaneous proliferation correction, A431 cells were stably transfected with green fluorescent protein. The results indicate that the peak PPIX level is a function of both, incubation concentration and period: maximal PPIX is generated with 1 to 2-mM ALA/MAL or 0.125-mM HAL; also, the PPIX peak shifts to longer incubation periods with increasing pro-drug concentrations. The results underline the need for detailed temporal analysis of PPIX formation to optimize ALA (derivative)-based PDT or photodiagnosis and highlight the value of environment-controlled microplate readers for automated in vitro analysis.


Assuntos
Ácido Aminolevulínico/administração & dosagem , Ácido Aminolevulínico/farmacocinética , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Fotoquimioterapia/métodos , Protoporfirinas/metabolismo , Espectrometria de Fluorescência/métodos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas Computacionais , Relação Dose-Resposta a Droga , Humanos , Radiossensibilizantes/administração & dosagem , Radiossensibilizantes/farmacocinética
7.
Radiat Environ Biophys ; 48(1): 47-56, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18797910

RESUMO

In the mountainous "Hohe Tauern" region of Salzburg (Austria), milk samples have been collected in a long-term montitoring programme since 1988, at eight alpine sites used for extensive, seasonal stock farming. For this alpine environment with its acidic soils developed on silicate bedrock, high soil-to-plant transfer factors and long-lasting (137)Cs contamination levels in milk--the main product of seasonal agriculture at elevated altitudes--are characteristic features. The decrease in (137)Cs concentration in milk measured since 1988 turned out to be best described by one or two effective half-lives. For the period from 1993 to 2007, which can be modelled with one effective half-life for all sites, effective half-lives between 3.7 and 15.0 years (ecological half-lives: 4.3-29.9 years) were obtained. The effective half-life increases with mean altitude of the investigated graze pastures, probably due to reduced migration velocities of (137)Cs and low (137)Cs half-value depths of a few centimetres in the soil.


Assuntos
Agricultura , Ecossistema , Leite/metabolismo , Animais , Áustria , Radioisótopos de Césio/farmacocinética , Coleta de Dados , Cadeia Alimentar , Meia-Vida , Solo , Fatores de Tempo
8.
J Environ Radioact ; 98(3): 329-45, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17707559

RESUMO

In general, indoor radon concentration is subject to seasonal variability. The reasons are to be found (1) in meteorological influence on the transport properties of soil, e.g. through temperature, frozen soil layers and soil water saturation; and (2) in living habits, e.g. the tendency to open windows in summer and keep them closed in winter, which in general leads to higher accumulation of geogenic Rn in closed rooms in winter. If one wants to standardize indoor Rn measurements originally performed at different times of the year, e.g. in order to make them comparable, some correction transform as a function of measurement time which accounts for these effects must be estimated. In this paper, the seasonality of indoor Rn concentration measured in Austria is investigated as a function of other factors that influence indoor Rn. Indoor radon concentration is clearly shown to have seasonal variability, with higher Rn levels in winter. However, it is complicated to quantify the effect because, as a consequence of the history of an Rn survey, the measurement season maybe correlated to geological regions, which may introduce a bias in the estimate of the seasonality amplitude.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Áustria , Estações do Ano
9.
J Environ Radioact ; 86(1): 12-30, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16171910

RESUMO

The Gastein valley in the Central Part of the Austrian Alps was one of the regions most heavily affected by fallout of the Chernobyl nuclear catastrophe, depositing (137)Cs inventory up to 70 kBq/m(2) in May 1986. In many studies dealing with the uptake of (137)Cs by vegetation used for farming, a significant correlation between (137)Cs concentration in the plants and altitude a.s.l. has been observed. In order to quantify the influence of the composition of plant communities on the average (137)Cs concentration in vegetation on farmland, plant-specific activity concentrations in plant species have been determined. Alongside a transect from valley sites at 850 m a.s.l. to alpine pastures at 1660 m, the aggregated transfer factors C(ag) (m(2)/kg) have been measured for plant communities and plant species. C(ag) values for mixed vegetation are more or less similar in valley sites, but they increase exponentially with a doubling height of 122+/-22 m above appr. 1200 m altitude a.s.l. On average all species are affected by this increase in a similar way. C(ag) values of ubiquitous plant indicate that the composition of plant communities is of minor importance for the contamination of mixed vegetation.


Assuntos
Altitude , Radioisótopos de Césio/análise , Plantas/química , Poluentes Radioativos do Solo/análise , Áustria , Acidente Nuclear de Chernobyl , Monitoramento de Radiação
10.
J Environ Radioact ; 79(2): 107-18, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15603901

RESUMO

This study focuses on radiocesium storage in soil microbial biomass of undisturbed alpine meadow sites and its relation to the soil-to-plant transfer. Soil and plant samples were taken in August 1999 from an altitude transect (800-1600m.a.s.l.) at Gastein valley, Austria. Soil samples were subdivided into 3-cm layers for analyses of total, K(2)SO(4)-extractable and microbially stored (137)Cs. Microbial biomass was measured by the fumigation extraction method, and fungal biomass was quantified using ergosterol as biomarker molecule. In general, the quantity of (137)Cs stored in the living soil microbial biomass was relatively small. At the high-altitude meadows, showing high amounts of fungal biomass, microbially stored (137)Cs amounted to 0.64+/-0.14kBqm(-2) which corresponds to about 1.2-2.7% of the total (137)Cs soil inventory. At lower altitudes, microbial (137)Cs content was distinctly smaller and in most cases not measurable at all using the fumigation extraction method. However, a positive correlation between the observed soil-to-plant aggregated transfer factor, microbially stored (137)Cs and fungal biomass was found, which indicates a possible role of fungal biomass in the storage and turnover of (137)Cs in soils and in the (137)Cs uptake by plants.


Assuntos
Biomassa , Radioisótopos de Césio/análise , Microbiologia do Solo , Poluentes Radioativos do Solo/análise , Solo/análise , Áustria , Monitoramento Ambiental , Fungos , Plantas/química
11.
In. Craig Conklin, W; Blue,Charles; Nanko,Lisa; Carpentier, Marcia; Wyvill, Bonnie; Kahn, Miles; Nawar, Madeleine; Lyman,Rick. Proceedings of the 1998 international radiological post - emergency response issues conference. Washington, U.S. Environmental Protection Agency (EPA). Office of Radiation and Indoor Air, Sept. 1998. p.118-22, ilus.
Monografia em En | Desastres | ID: des-10890
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