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1. This was in the press this week, I enclose the abstract from PubMed for further study.

Comment in: Biochem J. 2007 Aug 1;405(3):e5-6. Mechanism of short-term ERK activation by electromagnetic fields at mobile phone frequencies. Friedman J, Kraus S, Hauptman Y, Schiff Y, Seger R. Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 76100, Israel. The exposure to non-thermal microwave electromagnetic fields generated by mobile phones affects the expression of many proteins. This effect on transcription and protein stability can be mediated by the MAPK (mitogen-activated protein kinase) cascades, which serve as central signalling pathways and govern essentially all stimulated cellular processes. Indeed, long-term exposure of cells to mobile phone irradiation results in the activation of p38 as well as the ERK (extracellular-signal-regulated kinase) MAPKs. In the present study, we have studied the immediate effect of irradiation on the MAPK cascades, and found that ERKs, but not stress-related MAPKs, are rapidly activated in response to various frequencies and intensities. Using signalling inhibitors, we delineated the mechanism that is involved in this activation. We found that the first step is mediated in the plasma membrane by NADH oxidase, which rapidly generates ROS (reactive oxygen species). These ROS then directly stimulate MMPs (matrix metalloproteinases) and allow them to cleave and release Hb-EGF [heparin-binding EGF (epidermal growth factor)]. This secreted factor activates the EGF receptor, which in turn further activates the ERK cascade. Thus this study demonstrates for the first time a detailed molecular mechanism by which electromagnetic irradiation from mobile phones induces the activation of the ERK cascade and thereby induces transcription and other cellular processes.

MID: 17456048 [PubMed - indexed for MEDLINE] Article Preview fron www.newscientist.com Cellphones affect human cells without heating them * 30 August 2007 * Caroline Williams * Magazine issue 2619 CELLPHONE makers take great care to ensure their gadgets don't heat up your brain, but could the radiation cellphones throw out damage your cells in some other way? Israeli researchers have now identified a mechanism through which the radiation may affect the differentiation and division of cells. Claims of connections between cellphone radiation exposure and health problems such as cancer have been controversial, largely due to a lack of convincing evidence, but also because no clear mechanism was known by which radiation at cellphone frequencies and power levels could harm living cells. The frequencies are too low to damage DNA directly and the power of the signal is well below the level that could overheat cells. Previous evidence of non-thermal effects on cells is mixed, because it is very difficult to expose cells to radiation without heating them to some degree. In the new study, Joseph Friedman and colleagues at ... The complete article is 630 words long.

Bioelectromagnetics 09-01-2007

2. Some recent news from the German Mobile Telecommunication Research Programme (DMF)., which is partially available in English.

--a report on the SAR values measured using cellphones with headsets

--a report on public exposure hazards from WIMAX senders

--Determination of whole-body specific absorption rates in children by means of numerical computations The site is in German, but part of it has been translated into English. Some of the reports are also in English. You can subscribe to the DMF newsletter for free, and I will be commenting about the reports later. Scott Hill Frontier sciences group Copenhagen A number of expert workshops and colloquia will be carried out within the framework of the German Mobile Telecommunication Research Programme (DMF). These events serve to generate expert discussion on research requirements - requirements met by international consensus. These events also serve to support expert guidance and evaluation of ongoing research and discussion of planned research projects (see research projects). Participants in these events are scientists of scientific institutes with relevant experience as well as representatives of public institutions involved in this subject. Final results will be posted here. The first workshop on 'Research projects on the effects of electromagnetic fields from mobile telecommunications' took place in Neuherberg at the Federal Office for Radiation Protection (BfS) from 21-22 June 2001. This workshop served to elaborate the research emphasis of the German Mobile Telecommunication Research Programme (DMF). Proceedings of the 1st Workshop on 'Research Projects on the effects of electromagnetic fields from Mobile telecommunications' are available from the site link below. link to the partially English site:

http://www.emf-forschungsprogramm.de/akt_emf_forschung.html

Bioelectromagnetics 09-01-2007

3. I received the following email from James Bare. Apparently he hasn't been able to reach the forum, so here's his question on cellular memrane amplification.
Coincidiently I did a study on this phenomenon in my PhD, James so let me answer you briefly as follows:

An E-field in the extracellular medium causes the diffusion of proteins laying within the plasma membrane. This is similar to the formation of a crystal lattice but within the membrane. The E-field can cause many many cells to "polarize" in this fashion. Each of these polarized cells thus amplify the original signal. This is the mechanism within the ELF region and is the reason behind "alpha dispersion" or why some tissues have an epsilon_relative of more than 10^7!! Within other regions of dielectric dispersion there are other mechanism at work, but this one is responsible for getting cells to initiate growth and development of cells within the cell cycle. Maybe others have some more detail they can shed on this intruiging phenomenon. I seem to remember Froelich I think talking about "cell-cell" communication about 20 years ago. Cellular membranes can apparently amplify oscillating electrical fields. Can someone explain/elaborate a bit on this mechanism? I haven't seen this discussed previously in regards to EM field effects, and intuitively the phenomena seems very important.

Second-order model of membrane electric field induced byalternating external electric fields Kotnik, T.; Miklavcic, D. Biomedical Engineering, IEEE Transactions on Volume 47, Issue 8, Aug 2000 Page(s):1074 - 1081 Digital Object Identifier 10.1109/10.855935 Summary:With biological cells exposed to ac electric fields below 100 kHz, external field is amplified in the cell membrane by a factor of several thousands (low-frequency plateau), while above 100 kHz, this amplification gradually decreases with frequency. Below 10 MHz, this situation is well described by the established first-order theory which treats the cytoplasm and the external medium as pure conductors. At higher frequencies, capacitive properties of the cytoplasm and the external medium become increasingly important and thus must be accounted for. This leads to a broader, second-order model, which is treated in detail in this paper. Unlike the first-order model, this model shows that above 10 MHz, the membrane field amplification stops decreasing and levels off again in the range of tens (high-frequency plateau). Existence of the high-frequency plateau could have an important impact on present theories of high-frequency electric fields effects on cells and their membranes There is also a paper on this web site that investigates the response on molecular motors. http://www.isso.uh.edu/publications/A2005/2005_076_miller.htm

Bioelectromagnetics 09-05-2007