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BACKGROUND: Genetic factors may influence an individual's sensitivity to ionising radiation and therefore modify his/her risk of developing papillary thyroid carcinoma (PTC). Previously, we reported that common single nucleotide polymorphisms (SNPs) within the DNA damage recognition gene ATM contribute to PTC risk in Belarusian children exposed to fallout from the Chernobyl power plant accident. Here we explored in the same population the contribution of a panel of DNA repair-related SNPs in genes acting downstream of ATM. METHODS: The association of 141 SNPs located in 43 DNA repair genes was examined in 75 PTC cases and 254 controls from the Gomel region in Belarus. All subjects were younger than 15 years at the time of the Chernobyl accident. Conditional logistic regressions accounting for radiation dose were performed with PLINK using the additive allelic inheritance model, and a linkage disequilibrium (LD)-based Bonferroni correction was used for correction for multiple testing. RESULTS: The intronic SNP rs2296675 in MGMT was associated with an increased PTC risk [per minor allele odds ratio (OR) 2.54 95% CI 1.50, 4.30, P per allele = 0.0006, P corr.= 0.05], and gene-wide association testing highlighted a possible role for ERCC5 (P Gene = 0.01) and PCNA (P Gene = 0.05) in addition to MGMT (P Gene = 0.008). CONCLUSIONS: These findings indicate that several genes acting in distinct DNA repair mechanisms contribute to PTC risk. Further investigation is needed to decipher the functional properties of the methyltransferase encoded by MGMT and to understand how alteration of such functions may lead to the development of the most common type of thyroid cancer.

Background Light exposure and more specifically the spectrum of blue light contribute to the oxidative stress in Age-related macular degeneration (AMD). The purpose of the study was to establish whether blue light filtering could modify proangiogenic signaling produced by retinal pigmented epithelial (RPE) cells under different conditions simulating risk factors for AMD. Methods Three experiments were carried out in order to expose ARPE-19 cells to white light for 48 h with and without blue light-blocking filters (BLF) in different conditions. In each experiment one group was exposed to light with no BLF protection, a second group was exposed to light with BLF protection, and a control group was not exposed to light. The ARPE-19 cells used in each experiment prior to light exposure were cultured for 24 h as follows: Experiment 1) Normoxia, Experiment 2) Hypoxia, and Experiment 3) Lutein supplemented media in normoxia. The media of all groups was harvested after light exposure for sandwich ELISA-based assays to quantify 10 pro-angiogenic cytokines. Results A significant decrease in angiogenin secretion levels and a significant increase in bFGF were observed following light exposure, compared to dark conditions, in both normoxia and hypoxia conditions. With the addition of a blue light-blocking filter in normoxia, a significant increase in angiogenin levels was observed. Although statistical significance was not achieved, blue light filters reduce light-induced secretion of bFGF and VEGF to near normal levels. This trend is also observed when ARPE-19 cells are grown under hypoxic conditions and when pre-treated with lutein prior to exposure to experimental conditions. Conclusions Following light exposure, there is a decrease in angiogenin secretion by ARPE-19 cells, which was abrogated with a blue light - blocking filter. Our findings support the position that blue light filtering affects the secretion of angiogenic factors by retinal pigmented epithelial cells under normoxic, hypoxic, and lutein-pretreated conditions in a similar manner.

Exposure to ionizing radiation is ubiquitous, and it is well established that moderate and high doses cause ill-health and can be lethal. The health effects of low doses or low dose-rates of ionizing radiation are not so clear. This paper describes a project which sets out to summarize, as a restatement, the natural science evidence base concerning the human health effects of exposure to low-level ionizing radiation. A novel feature, compared to other reviews, is that a series of statements are listed and categorized according to the nature and strength of the evidence that underpins them. The purpose of this restatement is to provide a concise entrée into this vibrant field, pointing the interested reader deeper into the literature when more detail is needed. It is not our purpose to reach conclusions on whether the legal limits on radiation exposures are too high, too low or just right. Our aim is to provide an introduction so that non-specialist individuals in this area (be they policy-makers, disputers of policy, health professionals or students) have a straightforward place to start. The summary restatement of the evidence and an extensively annotated bibliography are provided as appendices in the electronic supplementary material.

Es van irradiar rates Sprague-Dawley amb 200 rads en els dies embrionaris 14, 16 i 18, i es van estudiar les malformacions produïdes amb fincions amb hematoxilinaeosina i mètode de Golgi ràpid, així com el patró de migració neuronal amb autorradiografia amb timidina tritiada. Les malformacions originals son un bon model experimental per a comparar amb algunes malalties humanes. Irradiant en ED 14 s'observa l'aparició de masses ectòpiques subcorticals produïdes per la migració neuronal anormal des dels centres germinals ectòpics o rosetes i l'estructura d'aquestes masses es estudiada amb detall. El patró de migració al còrtex és normal i les alteracions de la seva forma mínimes. Irradiant en ED 16 s'obté el màxim gran de desorganització en el neocortex conservant-se, però, el patró normal de migració. En ED 18 les alteracions observades es limiten a l'organització postmigratòria de les capes superiors del còrtex. L'hipocamp és alterat puntualment en irradiar els dies ED 14 i ED 16 sobre tot en les regions CA 1 i CA 2 del stratum pyramidale de la banya d'Ammon.

Bibliografia. Notes

Excmo. Sr, Señores Académicos, Señores: En estos momentos se aviva en mi ánimo el recuerdo de la intensa emoción sentida al venir por primera vez a esta Casa, con motivo de haberos dignado concedernos en 1899, con mi muy querido primo, colega y colaborador doctor Prió, el honor de dar una conferencia extraordinaria acerca del <>. Por lo de entonces y por la senalada prueba de benevolencia de hoy, acepte esta Corporación el testimonio de mi más respetuoso reconocimiento y la seguridad de que procuraré corresponder con todas mis energías a la tan honrosa distinción de que soy objeto. Permitidme rendir el más sentido y respetuoso homenaje a la buena memoria de los que fueron individuos de esta digna Academia, en especial a mis maestros los doctores Robert, Giné, Coll y Pujol, Pi y Suner, y además a quien en la citada fecha (1899) era Presidente, el primer electroterapeuta español, el Excmo. Sr. D. Eduardo Bertrán y Rubio; de todos ellos, y particularmente de los nombrados, perdurará durante toda mi vida, no sólo el recuerdo de sus innumerables y precalaras dotes, sí que también el de sus enseñanzas.

Des de fa un bon grapat de dècades, un dels costums més generalitzats a l'estiu és prendre el sol i permetre que l'astre rei ens escalfi la pell i la bronzegi. Certament, la llum solar exerceix una influència molt beneficiosa sobre el nostre organisme. D'una banda, el nostre cos la necessita per poder aprofitar determinades vitamines, com la vitamina D. També és molt eficaç en determinats processos dolorosos que afecten els ossos, la musculatura i les articulacions. A més, el sistema nerviós respon a la presència de llum solar produint endorfines, unes hormones que s'assemblen als opioides, les quals contribueixen a produir una sensació de benestar general [...].