Fluorescence in situ hybridisation study of micronuclei in C3A cells following exposure to ELF-magnetic fields

Human C3A cells were exposed to extremely low frequency (50 Hz) magnetic fields (ELF-MF's) up to 500 mu T. They were subjected to the micronucleus assay using a Fluorescence In Situ Hybridization (FISH) technique with an in-house pan-centromere probe. We found no increased frequency in micronucleated cells and no change in the proportion of centromere positive over centromere negative micronuclei compared to the unexposed control cells. These results are in accordance with some, but in contradiction with other previously published investigations underlining that effects of environmental ELF-EMF's on cellular DNA may be very subtle and that small changes or environmental influences may determine the outcome of a (geno)toxicity study. Interestingly, a low-level (5 mu T) exposure resulted in less than the background micronucleus frequency

Gene and Protein Expression following Exposure to Radiofrequency Fields from Mobile Phones

Background: Since 1999, several articles have been published on genome-wide and/or proteomewide response after exposure to radiofrequency (RF) fields whose signal and intensities were similar to or typical of those of currently used mobile telephones. These studies were performed using powerful high-throughput screening techniques (HTSTs) of transcriptomics and/or proteomics, which allow for the simultaneous screening of the expression of thousands of genes or proteins. Objectives: We reviewed these HTST-based studies and compared the results with currently accepted concepts about the effects of RF fields on gene expression. In this article we also discuss these last in light of the recent concept of microwave-assisted chemistry. Discussion: To date, the results of HTST-based studies of transcriptomics and/or proteomics after exposure to RF fields relevant to human exposure are still inconclusive, as most of the positive reports are flawed by methodologic imperfections or shortcomings. In addition, when positive findings were reported, no precise response pattern could be identified in a reproducible way. In particular, results from HTST studies tend to exclude the role of a cell stressor for exposure to RF fields at nonthermal intensities. However, on the basis of lessons from microwave-assisted chemistry, we can assume that RF fields might affect heat-sensitive gene or protein expression to an extent larger than would be predicted from temperature change only. But in all likelihood, this would concern intensities higher than those relevant to usual human exposure. Conclusions: The precise role of transcriptomics and proteomics in the screening of bioeffects from exposure to RF fields from mobile phones is still uncertain in view of the lack of positively identified phenotypic change and the lack of theoretical, as well as experimental, arguments for specific gene and/or protein response patterns after this kind of exposure.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Detection and toxicity evaluation of pyrrolizidine alkaloids in medicinal plants Gynura bicolor and Gynura divaricata collected from different Chinese locations

Two edible plants in Southeast Asia, Gynura bicolor and G.divaricata, are not only known to be nutritive but also useful as medicinal herbs. Previous phytochemical investigation of Gynura species showed the presence of hepatotoxic pyrrolizidine alkaloids (PAs), indicating the toxic risk of using these two plants. The present study was designed to analyze the distribution of PA components and tried to evaluate the preliminary toxicity of these two Gynura species. Eight samples of G.bicolor and G.divaricata from five different Chinese locations were collected and their specific PAs were qualitatively characterized by applying an UPLC/MS/MS spectrometry method. Using a pre-column derivatization HPLC method, the total retronecine ester-type PAs in their alkaloids extracts were quantitatively estimated as well. Finally, their genotoxicity was investigated with an effective high-throughput screening method referred to as Vitotox test and their potential cytotoxicity was tested on HepG2 cells. It was found that different types of PAs were widely present in Gynura species collected from south of China. Among them, no significant genotoxic effects were detected with serial concentrations through the present invitro assay. However, the cytotoxicity assay of Gynura plants collected from Jiangsu displayed weak activity at the concentration of 100mg/ml. It is important to note that this research validates in part the indication that the use of Gynura species requires caution

In vitro ispitivanje genotoksičnosti procjednih voda iz odlagališta otpada grada Settata u Maroku

With the increasing use of landfill sites, leachates produced by uncontrolled waste disposal have became a serious threat for the aquatic environment. The aim of this study was to evaluate the genotoxicity of leachate and of well water sampled close to the town of Settat in Morocco using the micronucleus test and proliferation kinetics of human peripheral blood lymphocytes in vitro. We also analysed a number of physical and chemical parameters, including pH, % O2, chemical oxygen demand (COD), HCO3-, Ca2+, Mg2+, Cl-, and conductivity. The analysis showed much higher levels of nearly all parameters than the Moroccan standard. Increased micronucleus frequencies were also found for both leachate and well water. Preliminary results indicate that both types of water are genotoxic and pose environmental and human health risk.Sve veća uporaba i stvaranje procjednih voda iz nekontroliranih odlagališta krutoga otpada postali su ozbiljna prijetnja vodenom okolišu. Cilj je ovog istraživanja bio procijeniti genotoksičnost takvih procjednih voda te podzemnih voda uzorkovanih iz bunara u blizini odlagališta otpada grada Settata u Maroku. U tu svrhu rabili smo mikronukleusni test in vitro i usporedno istražili kinetiku proliferacije limfocita periferne krvi zdrave dobrovoljne ispitanice. Osim toga, analizirano je više fizikalno-kemijskih parametara (nitrati, ortofosfati, nitriti, pH, otopljeni kisik, kemijska potrošnja kisika, temperatura, zamućenost vode). Te su analize procjednih voda i vode iz bunara pokazale brojna odstupanja od propisanih marokanskih standarda. Usto je u limfocitima izlaganim ovim vodama utvrđena i povišena učestalost mikronukleusa. Preliminarni nalazi pokazuju da su obje vrste voda genotoksične i da su mogući izvor rizika za okoliš i ljudsko zdravlje

The Wellesley News (01-19-1933)

https://repository.wellesley.edu/news/1936/thumbnail.jp

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ДВД, посветено на традиционалната музичка и играорна култура на Македонците муслимани