12 research outputs found
Państwo i społeczeństwo w XXI wieku : harmonizacja europejskiej przestrzeni współpracy w dziedzinie prawa, kultury i turystyki
Słowo wstępne
"Poszerzenie Unii Europejskiej w maju 2004 roku różniło się zasadniczo od wcześniejszych. Wymagało bowiem od państw kandydujących nie tylko ogromnego wysiłku dostosowawczego. Daje się ono porównać raczej z początkowym okresem integracji. Wtedy także trzeba było wkroczyć na zupełnie nieznane ścieżki, które stopniowo doprowadziły do jednolitego systemu instytucjonalnego i prawnego, na którym dziś opiera się Wspólnota. Kraje środkowej części naszego kontynentu wchodziły do Unii również z oczekiwaniem, że członkostwo podniesie rangę tych państw na arenie międzynarodowej oraz jednoznacznie określi ich nową pozycję w Europie. Jednoczenie się Europy jest wyrazem głębokiej wspólnoty kulturowej, czerpiącej ze śródziemnomorskich korzeni naszej cywilizacji."(...
Toward the development of transcriptional biodosimetry for the identification of irradiated individuals and assessment of absorbed radiation dose
Characterization of gene expression profiles at low and very low doses of ionizing radiation
International audienceThe aim of the present study is to analyse by microarray techniques how gene expression is modulated after exposure to low and very low doses of ionizing radiation, to evaluate if the pattern of gene expression shows dose dependence, and to search for putative regulatory mechanisms behind the observed gene-expression modifications. For this, whole blood samples from five healthy donors were exposed in six doses between 5 and 500mGy. Total RNA extraction from CD4+ lymphocytes was done at four different post-irradiation times. After mRNA amplification, aRNAs were hybridized on DNA microarrays. The results indicated that up-regulation was twice than down-regulation. Surprisingly, the number of modulated genes does not seem to change drastically with dose, even at the lowest dose of 5. mGy. Clustering analysis revealed seven gene expression clusters with different dose dependence profiles. The functional analysis showed that the genes which increased their expression with the dose were related to p53 pathway and DNA damage response. This could be observed from 25. mGy, but became very clear at doses equal or greater than 100. mGy. On the other hand, genes with a constant modulation of their expression in all the tested doses were related to cellular respiration, ATP metabolic process and chromatin organization. These latter molecular mechanisms seem to be triggered at very low doses (5-25. mGy). In silico promoter analysis seems to confirm the implication of transcription factors related to the pathways mentioned above. © 2013 Elsevier B.V
Low-dose irradiation of human fibroblasts leads to delayed acceleration of proliferation of their progeny
Radiation-induced alternative transcription and splicing events and their applicability to practical biodosimetry
Differences in DNA Repair Capacity, Cell Death and Transcriptional Response after Irradiation between a Radiosensitive and a Radioresistant Cell Line
Normal tissue toxicity after radiotherapy shows variability between patients, indicating inter-individual differences in radiosensitivity. Genetic variation probably contributes to these differences. The aim of the present study was to determine if two cell lines, one radiosensitive (RS) and another radioresistant (RR), showed differences in DNA repair capacity, cell viability, cell cycle progression and, in turn, if this response could be characterised by a differential gene expression profile at different post-irradiation times. After irradiation, the RS cell line showed a slower rate of γ-H2AX foci disappearance, a higher frequency of incomplete chromosomal aberrations, a reduced cell viability and a longer disturbance of the cell cycle when compared to the RR cell line. Moreover, a greater and prolonged transcriptional response after irradiation was induced in the RS cell line. Functional analysis showed that 24 h after irradiation genes involved in “DNA damage response”, “direct p53 effectors” and apoptosis were still differentially up-regulated in the RS cell line but not in the RR cell line. The two cell lines showed different response to IR and can be distinguished with cell-based assays and differential gene expression analysis. The results emphasise the importance to identify biomarkers of radiosensitivity for tailoring individualized radiotherapy protocols
A quantitative analysis of the abundance and demography of European hares Lepus europaeus in relation to habitat type, intensity of agriculture and climate
1. European hares Lepus europaeus have declined throughout Europe since the 1960s. Possible reasons for this include agricultural intensification and changes in climate and predator numbers, but no clear consensus has been reached as to the relative importance of each of these. We aimed to identify factors associated with high and low hare numbers throughout Europe, to determine which could have caused population declines. 2. Results of 77 research papers from 12 European countries were summarized. Relationships between hare density and demographics and habitat, climate, hunting and predator variables were examined and quantified where possible. Temporal changes in factors identified as being associated with high or low numbers of hares were then examined to see if they could explain population declines. 3. Data from pastural habitats were limited, but densities of hares were low. Arable habitats had higher densities than mixed areas in spring, unless farming was intensive in which case densities were similar. In autumn the two habitats had similar densities. Field size, temperature, precipitation and hunting had no effect on density throughout Europe. Fecundity was affected by climate. 4. Arable land, various crops, fallow habitat and temperature were positively associated, and monoculture, precipitation and predators negatively associated with hare abundance. The relationship of field size, pasture and woodland with abundance depended on spatial scale. 5. Habitat changes caused by agricultural intensification are the ultimate cause of hare population declines. Effects of changes in climate or predator numbers are magnified by the loss of high-quality year-round forage and cover. Further research is required on how habitat changes affect fecundity and survival, and to identify which parameters have the greatest impact on population numbers. Farmland management policies that target the re-establishment of some of the habitat diversity lost within fields, farms and landscapes will help to reverse the decline of the European hare