RESUMEN
We present a novel electro-optical solar compass that is able to determine the true North direction with an accuracy better than 1/100 of degree, superior to that of any other magnetic or electronic compass that does not resort to differential GPS. The compass has an electronic sensor to determine the line of sight of the Sun and a simple but effective algorithm to calculate the position of the Sun. The excellent results obtained during the experimental tests demonstrate the advantages of this compass, which is also compact and not expensive.
RESUMEN
The applications of Terahertz (THz) technologies have significantly developed in recent years, and the complete understanding of the biological effects of exposure to THz radiation is becoming increasingly important. In a previous study, we found that THz radiation induced genomic damage in fetal fibroblasts. Although these cells demonstrated to be a useful model, exposure of human foetuses to THz radiation is highly improbable. Conversely, THz irradiation of adult dermal tissues is cause of possible concern for some professional and nonprofessional categories. Therefore, we extended our study to the investigation of the effects of THz radiation on adult fibroblasts (HDF). In this work, the effects of THz exposure on HDF cells genome integrity, cell cycle, cytological ultrastructure and proteins expression were assessed. Results of centromere-negative micronuclei frequencies, phosphorylation of H2AX histone, and telomere length modulation indicated no induction of DNA damage. Concordantly, no changes in the expression of proteins associated with DNA damage sensing and repair were detected. Conversely, our results showed an increase of centromere-positive micronuclei frequencies and chromosomal nondisjunction events, indicating induction of aneuploidy. Therefore, our results indicate that THz radiation exposure may affect genome integrity through aneugenic effects, and not by DNA breakage. Our findings are compared to published studies, and possible biophysical mechanisms are discussed. Environ. Mol. Mutagen. 59:476-487, 2018. © 2018 Wiley Periodicals, Inc.
Asunto(s)
Aneuploidia , Aberraciones Cromosómicas/efectos de la radiación , Fibroblastos/efectos de la radiación , Radiación Terahertz/efectos adversos , Adulto , Ciclo Celular/efectos de la radiación , Línea Celular , Daño del ADN/efectos de la radiación , Fibroblastos/citología , Fibroblastos/metabolismo , Inestabilidad Genómica/efectos de la radiación , Humanos , Pruebas de Micronúcleos , Homeostasis del Telómero/efectos de la radiaciónRESUMEN
In the last decades, technological development has led to an increasing use of devices and systems based on microwave radiation. The increased employment of these devices has elicited questions about the potential long-term health consequences associated with microwave radiation exposure. From this perspective, biological effects of microwave radiation have been the focus of many studies, but the reported scientific data are unclear and contradictory. The aim of this study is to evaluate the potential genotoxic and cellular effects associated with in vitro exposure of human fetal and adult fibroblasts to microwave radiation at the frequency of 25 GHz. For this purpose, several genetic and biological end points were evaluated. Results obtained from comet assay, phosphorylation of H2AX histone, and antikinetochore antibody (CREST)-negative micronuclei frequency excluded direct DNA damage to human fetal and adult fibroblasts exposed to microwaves. No induction of apoptosis or changes in prosurvival signalling proteins were detected. Moreover, CREST analysis showed for both the cell lines an increase in the total number of micronuclei and centromere positive micronuclei in exposed samples, indicating aneuploidy induction due to chromosome loss.
Asunto(s)
Feto/patología , Fibroblastos/patología , Micronúcleos con Defecto Cromosómico/efectos de la radiación , Microondas/efectos adversos , Adulto , Aneuploidia , Células Cultivadas , Ensayo Cometa , Daño del ADN/efectos de la radiación , Feto/efectos de la radiación , Fibroblastos/efectos de la radiación , Histonas/genética , Humanos , Pruebas de MicronúcleosRESUMEN
The effects of pulsed 130 GHz radiations on lipid membrane permeability were investigated by using cationic liposomes containing dipalmitoyl phosphatidylcholine (DPPC), cholesterol, and stearylamine. Carbonic anhydrase (CA) was loaded inside the liposomes and the substrate p-nitrophenyl acetate (p-NPA) added in the bulk aqueous phase. Upon permeation across the lipid bilayer, the trapped CA catalyzes the conversion of the p-NPA molecules into products. Because the self-diffusion rate of p-NPA across intact liposomes is very low the CA reaction rate, expressed as Delta A/min, is used to track membrane permeability changes. The effect of 130 GHz radiation pulse-modulated at low frequencies of 5, 7, or 10 Hz, and at time-averaged incident intensity (I(AV)) up to 17 mW/cm(2) was studied at room temperature (22 degrees C), below the phase transition temperature of DPPC liposomes. At all the tested values of I(AV) a significant enhancement of the enzyme reaction rate in CA-loaded liposomes occurred when the pulse repetition rate was 7 Hz. Typically, an increase from Delta A/min = 0.0026 +/- 0.0010 (n = 11) to Delta A/min = 0.0045 +/- 0.0013 (n = 12) (P < 0.0005) resulted at I(AV) = 7.7 mW/cm(2). The effect of 130 GHz pulse-modulated at 7 Hz was also observed on cationic liposomes formed with palmitoyloleoyl phosphatidylcholine (POPC), at room temperature (22 degrees C), above the phase transition temperature of POPC liposomes.
Asunto(s)
Anhidrasas Carbónicas/química , Anhidrasas Carbónicas/efectos de la radiación , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/efectos de la radiación , Liposomas/química , Liposomas/efectos de la radiación , Microondas , Cationes , Relación Dosis-Respuesta a Droga , Permeabilidad/efectos de la radiación , Dosis de RadiaciónRESUMEN
In recent years, terahertz (THz) radiation has been widely used in a variety of applications: medical, security, telecommunications and military areas. However, few data are available on the biological effects of this type of electromagnetic radiation and the reported results, using different genetic or cellular assays, are quite discordant. This multidisciplinary study focuses on potential genotoxic and cytotoxic effects, evaluated by several end-points, associated with THz radiation. For this purpose, in vitro exposure of human foetal fibroblasts to low frequency THz radiation (0.1-0.15THz) was performed using a Compact Free Electron Laser. We did not observe an induction of DNA damage evaluated by Comet assay, phosphorylation of H2AX histone or telomere length modulation. In addiction, no induction of apoptosis or changes in pro-survival signalling proteins were detected. Moreover, our results indicated an increase in the total number of micronuclei and centromere positive micronuclei induction evaluated by CREST analysis, indicating that THz radiation could induce aneugenic rather than clastogenic effects, probably leading to chromosome loss. Furthermore, an increase of actin polymerization observed by ultrastructural analysis after THz irradiation, supports the hypothesis that an abnormal assembly of spindle proteins could lead to the observed chromosomal malsegregation.
Asunto(s)
Actinas/metabolismo , Centrómero/efectos de la radiación , Segregación Cromosómica/efectos de la radiación , Fibroblastos/efectos de la radiación , Micronúcleos con Defecto Cromosómico/estadística & datos numéricos , Aneuploidia , Apoptosis/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Centrómero/genética , Daño del ADN , Fibroblastos/metabolismo , Prepucio/citología , Prepucio/embriología , Histonas/metabolismo , Humanos , Técnicas In Vitro , Masculino , Fosforilación , Radiación TerahertzRESUMEN
Terahertz (THz) technology has emerged for biomedical applications such as scanning, molecular spectroscopy, and medical imaging. Although a thorough assessment to predict potential concerns has to precede before practical utilization of THz source, the biological effect of THz radiation is not yet fully understood with scant related investigations. Here, we applied a femtosecond-terahertz (fs-THz) pulse to mouse skin to evaluate non-thermal effects of THz radiation. Analysis of the genome-wide expression profile in fs-THz-irradiated skin indicated that wound responses were predominantly mediated by transforming growth factor-beta (TGF-ß) signaling pathways. We validated NFκB1- and Smad3/4-mediated transcriptional activation in fs-THz-irradiated skin by chromatin immunoprecipitation assay. Repeated fs-THz radiation delayed the closure of mouse skin punch wounds due to up-regulation of TGF-ß. These findings suggest that fs-THz radiation initiate a wound-like signal in skin with increased expression of TGF-ß and activation of its downstream target genes, which perturbs the wound healing process in vivo.