Cellular Phone User's Age or the Duration of Calls Moderate Autonomic Nervous System? A Meta-Analysis.

BACKGROUND: The European Health Risk Assessment Network on Electromagnetic Fields Exposure (EFHRAN) reported in 2012: "Children and adolescents represent the first generation of Europeans to be exposed to diffuse EMF since their conception and birth, thus, they are expected to be more sensitive to these fields." On the other hand, the body's physiologic processes are regulated by the autonomic nervous system (ANS) in a way that warrants further elucidation. OBJECTIVE: Age and duration of exposure are investigated for modifying the variance of the reported effects of mobile/cellular phone call (CPC) on ANS indexed, herein, by the heart rate variability (HRV). METHOD: Five studies targeted to 124 healthy subjects (aged 15.3-28.4 years (24.3 ± 5.2), who have been recorded in supine position before and/or sham versus real exposure (to a CPC lasting 5-32 minutes), are included in this meta-analysis. Age and duration of a CPC are evaluated as predictors in two separate meta-regressions. RESULTS: The meta-analysis identified a heterogeneity I2 = 63.2% for all outcomes and I2 = 65.2% for sympathovagal balance. Thus, we performed meta-regressions: for the sympathovagal balance rather than the combined parameters effect, the goodness of fit model presents significance only for age - the residual sum of squares compared to chi-square distribution (QR) is 4.24 for age (p = 0.12) - while, for minutes of exposure, QR = 8.2805 (p = 0.016). CONCLUSIONS: The sympathovagal balance - indispensible for health/homeostasis maintenance - is strongly predicted by age. Minutes of exposure did not affect overall HRV or sympathovagal balance. The results endorse/validate the EFHRAN 2012 suggestion for future research targeting to youngsters.

Gender differences in accident risk with e-bikes-Survey data from Norway.

E-bikes are becoming increasingly popular, and are given an important role in the green mobility of the future. However, some have raised concerns that the increased speed and the increased weight of the e-bike can lead to more accidents among cyclists riding an e-bike, as compared to conventional bicycles. Furthermore, it has been suggested that e-bikes may appeal to new groups of cyclists with little cycling experience, which may further impede cyclist safety. Previous research has not provided a clear picture. We investigate these questions with data from three surveys carried out in Norway (N = 7752). A logistic regression analysis comparing conventional and electric bicycles, controlling for age gender and exposure, shows an overall risk increase (all accidents) for e-bike users. The results suggest that this increased risk derives from females having a higher accident risk on e-bikes. For men there is no risk difference between e-bikes and conventional bikes. Some, but not all, of this elevated risk can be attributed to being unfamiliar with the bicycle. E-bikes are not more likely to cause serious accidents than conventional bicycles. In-depth analysis of accident causation showed that there was no difference in the factors leading to accidents, except that there was a somewhat higher prevalence of accidents resulting from balance problems with e-bikes.

Right on track? Performance of satellite telemetry in terrestrial wildlife research.

Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.

Electromagnetic fields may act via calcineurin inhibition to suppress immunity, thereby increasing risk for opportunistic infection: Conceivable mechanisms of action.

While a good number of studies have demonstrated that modern, man-made ambient electromagnetic fields can have both stimulatory and inhibitory effect on immune system function, the precise mechanisms have yet to be completely elucidated. It is hypothesized here that, depending on the parameters, one of the means by which long-term electromagnetic field exposure has the potential to eventually lead to immunosuppression is via downstream inhibition of the enzyme calcineurin - a protein phosphatase, which activates the T-cells of the immune system and can be blocked by pharmaceutical agents. Calcineurin is the target of a class of pharmaceuticals called calcineurin inhibitors (e.g., cyclosporine, pimecrolimus and tacrolimus). When organ transplant recipients take such pharmaceuticals to prevent or suppress organ transplant rejection, one of the major side effects is immunosuppression leading to increased risk of opportunistic infection: e.g., fungal, viral (Epstein-Barr virus, cytomegalovirus), atypical bacterial (Nocardia, Listeria, mycobacterial, mycoplasma), and parasitic (e.g., toxoplasmosis) infections. Frequent anecdotal reports, as well as a number of scientific studies, have shown that electromagnetic field exposures may indeed produce the same effect: a weakened immune system leading to an increase in the same or similar opportunistic infections: i.e., fungal, viral, atypical bacterial, and parasitic infections. Furthermore, numerous research studies have shown that man-made electromagnetic fields have the potential to open voltage-gated calcium channels, which can in turn produce a pathological increase of intracellular calcium, leading downstream to the pathological production of a series of reactive oxygen species. Finally, there are a number of research studies demonstrating the inhibition of calcineurin by a pathological production of reactive oxygen species. Hence, it is hypothesized here that exposures to electromagnetic fields have the potential to inhibit immune system response by means of an eventual pathological increase in the influx of calcium into the cytoplasm of the cell, which induces a pathological production of reactive oxygen species, which in turn can have an inhibitory effect on calcineurin. Calcineurin inhibition leads to immunosuppression, which in turn leads to a weakened immune system and an increase in opportunistic infection.

Does the mosquito have more of a role in certain cancers than is currently appreciated? - The mosquito cocktail hypothesis.

The International Agency for Research on Cancer recognises five viruses, one bacterium and three parasites as having a causal relationship to cancer, and one virus, HIV, that by suppressing the immune system assists in the development of cancer. In addition numerous researchers have claimed links between cancer and other viruses and bacteria, many of which have been isolated from tumours. Excluding the non-causal HIV, 33 infectious agents linked with cancer have been identified in the literature, 27 of which have one thing in common: they are all present in mosquitoes. There are over 3000 species of mosquito and very few have been fully analysed, so the six remaining infectious agents may be present in some unexamined species. This hypothesis proposes that more cancers than are presently appreciated may arise from the long-term outcome of a mosquito bite, which by releasing a complex cocktail of up to 60 infectious agents directly into the blood stream, often results in contemporaneous immuno-suppression and a multiplicity of co-infections. These co-infections may act synergistically in whole, or in part, and in complex ways. Whether and if so which type of cancer ensues will depend on the constituent ingredients in the cocktail, determined by multiple factors such as the mosquito's drinking and feeding patterns, number of previous blood-meals and the variety of intermediate hosts from which these meals are taken. Only a few mosquito species carry malaria, dengue fever, chikungunya and the other recognised serious human ailments. This hypothesis suggests that the number of species carrying the cancer cocktail will be few in number but collectively have a worldwide presence.

Reducing electromagnetic irradiation and fields alleviates experienced health hazards of VDU work.

UNLABELLED: Word Heath Organisation (WHO) outlined in 2005 recommendations, how to treat people suffering from the functional impairment electrohypersensitivity in its document "Electromagnetic fields and public health". Unfortunately the reduction of electromagnetic fields was not considered as a treatment option. The aim of the current study was to shield the computer user from the emitted electromagnetic irradiation and fields and to correlate that to the subjective symptoms reported by electrohypersensitive volunteers. The irradiation of the shielding cabinets was recorded. They housed either separate computer screens or whole laptops. When the volunteers had used the shielding cabinet for 1-7 years, they were able work with their computers whole working day, Those who had used the shielding cabined for 2-3 months were partially symptom free. The person who had used the cabinet only for 1 week reported some alleviation of her nausea. IN CONCLUSION: it seems that reducing the electromagnetic irradiation of the computer can lessen the symptoms of electrohypersensitivity and permit working without problems. Further studies are needed to clarify how the symptoms of different organ systems recover and make computer users to work also professionally.

Attitudes and perceptions towards oral hygiene tasks among geriatric nursing home staff.

OBJECTIVES: To assess attitudes and perceptions towards oral hygiene tasks among geriatric nursing home staff, before and after a dental hygiene education. METHODOLOGY: A survey questionnaire was distributed to the nursing staff (n = 105), at a geriatric nursing home in Stockholm, Sweden. RESULTS: The response rate to the questionnaire was 83%. A vast majority (87%) of the nursing staff considered oral hygiene tasks unpleasant. The main reason for considering oral care unpleasant was a perceived unwillingness from the residents. The perceived unwillingness from the residents among the nursing staff was reduced after the dental hygiene education (chi-square test, P = 0.02). A vast majority of the nursing staff experienced, always or sometimes, resistance from the residents towards oral care. CONCLUSIONS: Nursing home staff members consider oral care tasks unpleasant, and frequently experience resistance from the nursing home residents towards oral care. The perceived unwillingness from the residents is reduced after an advanced dental hygiene education. Further studies are needed to evaluate the effects of education on nursing staff's attitudes and perceptions towards oral care tasks, with the overall aim of improving the oral health among older people in hospitals and nursing homes.

Femtosecond electron spectroscopy of coronene, benzo[GHI]perylene, and anthracene.

The large polycyclic aromatic hydrocarbon molecules coronene, benzo[GHI]perylene, and anthracene have been ionized with femtosecond laser pulses at low laser intensities and the ionization process studied with velocity map imaging spectroscopy, supplemented with ion yield measurements. The electron spectra of coronene and benzo[GHI]perylene are structureless. Based on fluence and pulse duration dependence measurements, it is shown that the electron spectra are not produced in field ionization processes, and the ionization mechanism is identified to be a quasithermal statistical electron emission, previously suggested for the fullerenes C(60) and C(70). The anthracene photoelectron spectra are dominated by above threshold ionization features, but with some indication of quasithermal ionization at longer pulses.

European Federation of Neurological Societies/Peripheral Nerve Society Guideline on the use of skin biopsy in the diagnosis of small fiber neuropathy. Report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society.

BACKGROUND: Revision of the guidelines on the use of skin biopsy in the diagnosis of peripheral neuropathy, published in 2005, has become appropriate owing to publication of more relevant articles. Most of the new studies focused on small fiber neuropathy (SFN), a subtype of neuropathy for which the diagnosis was first developed through skin biopsy examination. This revision focuses on the use of this technique to diagnose SFN. METHODS: Task force members searched the Medline database from 2005, the year of the publication of the first EFNS guideline, to June 30th, 2009. All pertinent articles were rated according to the EFNS and PNS guidance. After a consensus meeting, the task force members created a manuscript that was subsequently revised by two experts (JML and JVS) in the field of peripheral neuropathy and clinical neurophysiology, who were not previously involved in the use of skin biopsy. RESULTS AND CONCLUSIONS: Distal leg skin biopsy with quantification of the linear density of intraepidermal nerve fibers (IENF), using generally agreed upon counting rules, is a reliable and efficient technique to assess the diagnosis of SFN (Recommendation Level A). Normative reference values are available for bright-field immunohistochemistry (Recommendation Level A) but not yet for confocal immunofluorescence or the blister technique. The morphometric analysis of IENF density, either performed with bright-field or immunofluorescence microscopy, should always refer to normative values matched for age (Recommendation Level A). Newly established laboratories should undergo adequate training in a well-established skin biopsy laboratory and provide their own stratified for age and gender normative values, intra- and interobserver reliability, and interlaboratory agreement. Quality control of the procedure at all levels is mandatory (Good Practice Point). Procedures to quantify subepidermal nerve fibers and autonomic innervated structures, including erector pili muscles, and skin vessels, are under development but need to be confirmed by further studies. Sweat gland innervation can be examined using an unbiased stereologic technique recently proposed (Recommendation Level B). A reduced IENF density is associated with the risk of developing neuropathic pain (Recommendation Level B), but it does not correlate with its intensity. Serial skin biopsies might be useful for detecting early changes of IENF density, which predict the progression of neuropathy, and to assess degeneration and regeneration of IENF (Recommendation Level C). However, further studies are warranted to confirm its potential usefulness as an outcome measure in clinical practice and research. Skin biopsy has not so far been useful for identifying the etiology of SFN. Finally, we emphasize that 3-mm skin biopsy at the ankle is a safe procedure based on the experience of 10 laboratories reporting absence of serious side effects in approximately 35,000 biopsies and a mere 0.19% incidence of non-serious side effects in about 15 years of practice (Good Practice Point).

Expression of both oestrogen receptor alpha and beta in human skeletal muscle tissue.

There are two oestrogen receptors (ERs), ERalpha and ERbeta. ERbeta protein is expressed in human skeletal muscle in the nuclei of both myofibres and endothelial cells, whether ERalpha protein is present in this tissue is unknown. We studied the expression of ERalpha protein in human skeletal muscle biopsies taken from vastus lateralis from four men, four women, two children and two postmenopausal women. Immunohistochemistry was used to determine the proportions of nuclei that were positively stained for ERalpha, the proportion of ERalpha-positive nuclei located in the muscle fibres and in capillaries and to test for possible co-expression of ERalpha and ERbeta. Both ERs were expressed in all subjects. Of all nuclei, 63% stained for ERalpha with no sex difference. ERalpha was localised both in myofibres and in endothelial cells of the capillaries, 25% of the ERalpha-positive nuclei were located in the capillaries. ERalpha and ERbeta were generally expressed in the same nuclei. The present study shows for the first time the expression of ERalpha protein in human skeletal muscle independently of age and sex. These results might improve understanding of the physiological role of oestrogen in human skeletal muscle and raise new questions about activation of ERs in skeletal muscle.

A personal digital assistant application (MobilDent) for dental fieldwork data collection, information management and database handling.

OBJECTIVE: To develop a personal digital assistant (PDA) application for oral health assessment fieldwork, including back-office and database systems (MobilDent). DESIGN: System design, construction and implementation of PDA, back-office and database systems. METHODS: System requirements for MobilDent were collected, analysed and translated into system functions. User interfaces were implemented and system architecture was outlined. MobilDent was based on a platform with. NET (Microsoft) components, using an SQL Server 2005 (Microsoft) for data storage with Windows Mobile (Microsoft) operating system. The PDA devices were Dell Axim. RESULTS: System functions and user interfaces were specified for MobilDent. User interfaces for PDA, back-office and database systems were based on. NET programming. The PDA user interface was based on Windows suitable to a PDA display, whereas the back-office interface was designed for a normal-sized computer screen. A synchronisation module (MS Active Sync, Microsoft) was used to enable download of field data from PDA to the database. CONCLUSIONS: MobilDent is a feasible application for oral health assessment fieldwork, and the oral health assessment database may prove a valuable source for care planning, educational and research purposes. Further development of the MobilDent system will include wireless connectivity with download-on-demand technology.

Detection of hydrogen peroxide using photofragmentation laser-induced fluorescence.

Photofragmentation laser-induced fluorescence (PF-LIF) is for the first time demonstrated to be a practical diagnostic tool for detection of hydrogen peroxide. Point measurements as well as two-dimensional (2D) measurements in free-flows, with nitrogen as bath gas, are reported. The present application of the PF-LIF technique involves one laser, emitting radiation of 266 nm wavelength, to dissociate hydrogen peroxide molecules into OH radicals, and another laser, emitting at 282.25 nm, to electronically excite OH, whose laser-induced fluorescence is detected. The measurement procedure is explained in detail and a suitable time separation between photolysis and excitation pulse is proposed to be on the order of a few hundred nanoseconds. With a separation time in that regime, recorded OH excitation scans were found to be thermal and the signal was close to maximum. The PF-LIF signal strength was shown to follow the same trend as the vapor pressure corresponding to the hydrogen peroxide liquid concentration. Thus, the PF-LIF signal appeared to increase linearly with hydrogen peroxide vapor-phase concentration. For 2D single shot measurements, a conservatively estimated value of the detection limit is 30 ppm. Experiments verified that for averaged point measurements the detection limit was well below 30 ppm.

EFNS guidelines on the use of skin biopsy in the diagnosis of peripheral neuropathy.

Skin biopsy has become a widely used tool to investigate small calibre sensory nerves including somatic unmyelinated intraepidermal nerve fibres (IENF), dermal myelinated nerve fibres, and autonomic nerve fibres in peripheral neuropathies and other conditions. Different techniques for tissue processing and nerve fibre evaluation have been used. In March 2004, a Task Force was set up under the auspices of the European Federation of Neurological Societies (EFNS) with the aim of developing guidelines on the use of skin biopsy in the diagnosis of peripheral neuropathies. We searched the Medline database from 1989, the year of the first publication describing the innervation of human skin using immunostaining with anti-protein-gene-product 9.5 (PGP 9.5) antibodies, to 31 March 2005. All pertinent papers were rated according to the EFNS guidance. The final version of the guidelines was elaborated after consensus amongst members of the Task Force was reached. For diagnostic purposes in peripheral neuropathies, we recommend performing a 3-mm punch skin biopsy at the distal leg and quantifying the linear density of IENF in at least three 50-mum thick sections per biopsy, fixed in 2% PLP or Zamboni's solution, by bright-field immunohistochemistry or immunofluorescence with anti-PGP 9.5 antibodies (level A recommendation). Quantification of IENF density closely correlated with warm and heat-pain threshold, and appeared more sensitive than sensory nerve conduction study and sural nerve biopsy in diagnosing small-fibre sensory neuropathy. Diagnostic efficiency and predictive values of this technique were very high (level A recommendation). Confocal microscopy may be particularly useful to investigate myelinated nerve fibres, dermal receptors and dermal annex innervation. In future, the diagnostic yield of dermal myelinated nerve fibre quantification and of sweat gland innervation should be addressed. Longitudinal studies of IENF density and regeneration rate are warranted to correlate neuropathological changes with progression of neuropathy and to assess the potential usefulness of skin biopsy as an outcome measure in peripheral neuropathy trials (level B recommendation). In conclusion, punch skin biopsy is a safe and reliable technique (level A recommendation). Training in an established cutaneous nerve laboratory is recommended before using skin biopsy as a diagnostic tool in peripheral neuropathies. Quality control at all levels is mandatory.

Expression of oestrogen receptor alpha and beta is higher in skeletal muscle of highly endurance-trained than of moderately active men.

AIM: Two known oestrogen receptors (ERs), ERalpha and the recently cloned ERbeta, are expressed in the human skeletal muscle of both males and females. The effects of oestrogen and the role of ERs in skeletal muscle tissue are not well known. Oestrogen receptors and some of their target genes are involved in angiogenic processes. It was hypothesized that ERs are expressed at a higher level in a group with higher oxidative capacity, and that such an enhanced expression would parallel expression of the angiogenic factor -- vascular endothelial growth factor (VEGF). METHOD: Muscle biopsies were taken from vastus lateralis in 10 highly endurance-trained males and 10 moderately active males and analysed for the expression of ERs and VEGF. RESULTS: The major findings in the present study were the higher mRNA levels of ERalpha, ERbeta and VEGF in the highly endurance-trained than in the moderately active group. CONCLUSION: These data suggest that the greater mRNA expression of ERalpha and ERbeta and the oestrogen-associated angiogenic factor VEGF support the hypothesis of an involvement of ERs in the adaptation of skeletal muscle to endurance training.

Oestrogen receptor beta is expressed in adult human skeletal muscle both at the mRNA and protein level.

AIM: There are two known oestrogen receptors (ER), oestrogen receptor alpha (ERalpha) and the recently cloned oestrogen receptor beta (ERbeta). ERalpha mRNA has been detected in mouse, rat, bovine and human skeletal muscle. ERbeta mRNA has been detected in bovine skeletal muscle. To our knowledge, no study has investigated the expression of oestrogen receptor beta in human skeletal muscle. Therefore, the primary aim of the present investigation was to study ERbeta mRNA and protein expression in human skeletal muscle. In addition the ERalpha expression was also studied. METHODS: Muscle biopsies were taken from vastus lateralis in six healthy adults (three women and three men). mRNA expression was detected with real-time PCR (TaqMan) and protein localization by immunohistochemistry. RESULTS: A clear expression of ERalpha and ERbeta mRNA was seen in skeletal muscle in all subjects. The ERalpha mRNA expression was 180 fold higher compared with that of ERbeta mRNA. Immunohistochemistry demonstrated positive staining for ERbeta, but not for ERalpha, with localization to the nuclei of skeletal muscle fibres. On average, 70% of all nuclei were ERbeta-positive. CONCLUSION: The present study shows for the first time ERbeta mRNA and protein expression in human skeletal muscle tissue in both males and females.

Identification of functional clusters of transcription factor binding motifs in genome sequences: the MSCAN algorithm.

MOTIVATION: The identification of regulatory control regions within genomes is a major challenge. Studies have demonstrated that regulating regions can be described as locally dense clusters or modules of cis-acting transcription factor binding sites (TFBS). For well-described biological contexts, it is possible to train predictive algorithms to discern novel modules in genome sequences. However, utility of module detection methods has been severely limited by insufficient training data. For only a few tissues can one obtain sufficient numbers of literature-derived regulatory modules. RESULTS: We present a novel method, MSCAN, that circumvents the training data problem by measuring the statistical significance of any non-overlapping combination of TFBS in a window. Given a set of transcription factor binding profiles, a significance threshold, and a genomic sequence, MSCAN returns putative regulatory regions. We assess performance on two curated collections of regulatory regions; one each for tissue-specific expression in liver and skeletal muscle cells. The efficiency of MSCAN allows for predictive screens of entire genomes.

Cutaneous mast cells are altered in normal healthy volunteers sitting in front of ordinary TVs/PCs--results from open-field provocation experiments.

BACKGROUND: Considerable controversy has surrounded the question of possible biological responses to electromagnetic fields (EMFs) generated from visual display terminals (VDTs), such as personal computers (PCs) and ordinary television sets (TVs). The cellular and molecular mechanisms for such potential harmful health hazards have not yet been understood, although clues from the literature include mast cells and histamine. The aim of this study was therefore to investigate possible biological mast cell responses to TV/PC screens. METHODS: Using the indirect immunofluorescence technique, we studied the presence of histamine-containing mast cells in the dermis of healthy volunteers. Cutaneous biopsies taken before and after exposure to ordinary TV/PC screens for 2 or 4 h were investigated in 13 healthy subjects. RESULTS: Our present in vivo study indicates that normal cutaneous mast cells could be altered by exposure from ordinary TV/PC screens. To our great surprise, we found the number of mast cells in the papillary and reticular dermis to increase, to varying degrees, in 5 out the 13 subjects after such an exposure. A migration of mast cells towards the uppermost dermis appeared as the most important event. Thus, the normally upper "empty zone" of the dermis disappeared, and instead, a higher density of mast cells were found in this zone. These cells also seemed to have a tendency to increase in number towards the epidermal-dermal junctional zone and some of them lost their granular content and the cytoplasm shrunk (=degranulation). These findings could only be seen in the exposed skin. Two of the 13 cases instead showed a decrease in mast cell number, but the shift in mast cells towards the upper dermis was still visible. Twenty-four h after the provocation, the cellular number and location were normalized in all subjects. CONCLUSIONS: By definition, normal healthy volunteers are assumed not to react to a TV/PC screen provocation. To our great surprise, this proved not to be true. The present results might lay a foundation to understand the underlying cause of so-called "screen dermatitis" with special reference to mast cells. However, blind or double-blind experiments using patients ought to be further investigated in order to find out the exact cause for the observed changes. Such causes include the effects of surrounding airborne chemicals, stress factors, etc.