Background: Risks from electromagnetic devices are of considerable concern. Electrohypersensitive (EHS) persons attribute a variety of rather unspecific symptoms to the exposure to electromagnetic fields. The pathophysiology of EHS is unknown and therapy remains a challenge. Objectives: Heavy metal load has been discussed as a potential factor in the symptomatology of EHS patients. The main objective of the study was to test the hypothesis of a link between EHS and heavy metal exposure.Methods: We measured lead, mercury and cadmium concentrations in the blood of 132 patients (n = 42 males and n = 90 females) and 101 controls (n = 34 males and n = 67 females).Results: Our results show that heavy metal load is of no concern in most cases of EHS but might play a role in exceptional cases.Conclusions: The data do not support the general advice to heavy metal detoxification in EHS. (C) 2009 Elsevier B.V. All rights reserved.

Background Tinnitus is a frequent condition with high morbidity and impairment in quality of life. The pathophysiology is still incompletely understood. Electromagnetic fields are discussed to be involved in the multi-factorial pathogenesis of tinnitus, but data proofing this relationship are very limited. Potential health hazards of electromagnetic fields (EMF) have been under discussion for long. Especially, individuals claiming themselves to be electromagnetic hypersensitive suffer from a variety of unspecific symptoms, which they attribute to EMF-exposure. The aim of the study was to elucidate the relationship between EMF-exposure, electromagnetic hypersensitivity and tinnitus using a case-control design. Methodology Tinnitus occurrence and tinnitus severity were assessed by questionnaires in 89 electromagnetic hypersensitive patients and 107 controls matched for age-, gender, living surroundings and workplace. Using a logistic regression approach, potential risk factors for the development of tinnitus were evaluated. Findings Tinnitus was significantly more frequent in the electromagnetic hypersensitive group (50.72% vs. 17.5%) whereas tinnitus duration and severity did not differ between groups. Electromagnetic hypersensitivity and tinnitus were independent risk factors for sleep disturbances. However, measures of individual EMF-exposure like e.g. cell phone use did not show any association with tinnitus. Conclusions Our data indicate that tinnitus is associated with subjective electromagnetic hypersensitivity. An individual vulnerability probably due to an over activated cortical distress network seems to be responsible for, both, electromagnetic hypersensitivity and tinnitus. Hence, therapeutic efforts should focus on treatment strategies (e.g. cognitive behavioral therapy) aiming at normalizing this dysfunctional distress network.

BACKGROUND:Hypersensitivity to electromagnetic fields (EMF) is frequently claimed to be linked to a variety of non-specific somatic and neuropsychological complaints. Whereas provocation studies often failed to demonstrate a causal relationship between EMF exposure and symptom formation, recent studies point to a complex interplay of neurophysiological and cognitive alterations contributing to symptom manifestation in electromagnetic hypersensitive patients (EHS). However, these studies have examined only small sample sizes or have focused on selected aspects. Therefore this study examined in the largest sample of EHS EMF-specific cognitive correlates, discrimination ability and neurobiological parameters in order to get further insight into the pathophysiology of electromagnetic hypersensitivity.METHOD:In a case-control design 89 EHS and 107 age- and gender-matched controls were included in the study. Health status and EMF-specific cognitions were evaluated using standardized questionnaires. Perception thresholds following single transcranial magnetic stimulation (TMS) pulses to the dorsolateral prefrontal cortex were determined using a standardized blinded measurement protocol. Cortical excitability parameters were measured by TMS.RESULTS:Discrimination ability was significantly reduced in EHS (only 40% of the EHS but 60% of the controls felt no sensation under sham stimulation during the complete series), whereas the perception thresholds for real magnetic pulses were comparable in both groups (median 21% versus 24% of maximum pulse intensity). Intra-cortical facilitation was decreased in younger and increased in older EHS. In addition, typical EMF-related cognitions (aspects of rumination, symptom intolerance, vulnerability and stabilizing self-esteem) specifically differentiated EHS from their controls.CONCLUSIONS:These results demonstrate significant cognitive and neurobiological alterations pointing to a higher genuine individual vulnerability of electromagnetic hypersensitive patients.

Functional somatic syndromes are characterized by high morbidity due to various, fluctuating symptoms without objective somatic findings. There is increasing evidence for the contribution of emotional and cognitive functions to symptom formation, which has been well established in the perception of pain. In addition to their involvement in various other cognitive and emotional processes, the anterior cingulate and insular cortex are thought to contribute to the so-called “pain neuromatrix”. Recent data suggest that these areas appear also to be involved in symptom manifestation in multiple chemical sensitivity. Here we used functional Magnetic Resonance Imaging (fMRI) to test whether this network is also involved in the induction of unpleasant perceptions by sham mobile phone radiation in subjectively electrosensitive patients. This design enabled us to completely dissociate the unpleasant subjective perception from any real physical stimulus. Fifteen subjectively electrosensitive patients and 15 age- and gender-matched healthy controls were exposed to sham mobile phone radiation and heat as a control condition. The perceived stimulus intensities were rated on a five-point scale. During anticipation of and exposure to sham mobile phone radiation increased activations in anterior cingulate and insular cortex as well as fusiform gyrus were seen in the electrosensitive group compared to controls, while heat stimulation led to similar activations in both groups. Symptom manifestation during sham exposure to mobile phone radiation was accompanied by specific alterations of cortical activity in anterior cingulate and insular cortex in subjectively electrosensitive patients further supporting the involvement of these areas in the perception of unpleasantness and generation of functional somatic syndromes.

OBJECTIVES It is well known that colour exposure can influence emotions, behaviour and perception. To get further insight into these complex synesthetic phenomena, the effect of colour stimulation on auditory and somatosensory perception was systematically investigated. METHODS 14 healthy male volunteers with normal colour vision rated the loudness of auditory stimuli with a standardized scale during exposure to white, red and green light. Furthermore temperature perception was assessed during exposure of the different colours using a thermal sensory analyser. RESULTS Colour exposure significantly altered auditory and somatosensory perception. Red light enhanced loudness perception and decreased cold pain thresholds, while green light stimulation reduced loudness perception and increased detection and pain thresholds for warm stimuli. CONCLUSIONS This data give further evidence for cross-modal plasticity in human perception. Colour stimulation influences auditory and somatosensory perception and may therefore have potential as a new treatment strategy of phantom perceptions such as tinnitus or chronic pain.

Fragestellung: Patienten mit einer subjektiven Uberempfindlichkeit gegenuber elektromagnetischen Feldern klagen haufig uber eine Vielzahl unspezifischer somatischer und/oder neuropsychologischer Symptome. Bisher konnte jedoch in zahlreichen Studien kein direkter kausaler Zusammenhang zwischen der Exposition mit elektromagnetischen Feldern und den geklagten Beschwerden nachgewiesen werden. Neuere Untersuchungen deuten daraufhin, dass an der Beschwerdeentstehung moglicherweise dysfunktionale Kognitionen (Antizipation, Fehl-Attribuierung) beteiligt zu sein scheinen. Mithilfe der funktionellen Kernspintomographie sollen die zugrundeliegenden neurobiologischen Prozesse dieser dysfunktionalen Kognitionen untersucht werden. Methoden: 15 subjektiv elektrosensible Patienten und ihre alters- und geschlechts-parallelisierten Kontrollen wurden mithilfe der funktionellen Kernspintomographie untersucht. Zum einen erfolgte eine Schein-Exposition mit elektromagnetischer Strahlung durch ein Dummy-Handy. Zum anderen wurden als Vergleichsbedingung unterschiedlich starke Warmereize im Bereich des linken Unterarms appliziert. Die Auswertung erfolgte mit SPM2. Ergebnisse: Wahrend der Schein-Exposition mit Handystrahlung findet sich bei subjektiv elektrosensiblen Patienten eine Aktivierung in einem weitverzweigten kortikalen Netzwerk (u.a. rostrales ACC, Inselkortex). Im Gegensatz dazu zeigt sich bei den Kontrollpersonen keinerlei Aktivierung unter dieser Expositionsbedingung. Schlussfolgerungen: Diese Ergebnisse deuten auf spezifische Unterschiede in der kortikalen Prozessierung zwischen subjektiv elektrosensiblen Patienten und gesunden Kontrollpersonen hin.

Objective: Hypersensitivity to electromagnetic fields is frequently claimed to be linked to a variety of unspecific somatic and/or neuropsychological complaints. Whereas provocation studies often failed to demonstrate a causal relationship between electromagnetic field exposure and symptom formation, neurophysiological examinations highlight baseline deviations in people claiming to be electrosensitive. Methods: To elucidate a potential role of dysfunctional cortical regulations in mediating hypersensitivity to electromagnetic fields, cortical excitability parameters were measured by transcranial magnetic stimulation in subjectively electro-sensitive patients (n=23) and two control groups (n=49) differing in their level of unspecific health complaints. Results: Electro-sensitive patients showed reduced intracortical facilitation as compared to both control groups, while motor thresholds and intracortical inhibition were unaffected. Conclusions: This pilot study gives additional evidence that altered central nervous system function may account for symptom manifestation in subjectively electrosensitive patients as has been postulated for several chronic multisymptom illnesses sharing a similar clustering of symptoms. (c) 2007 Elsevier Inc. All rights reserved.

ZusammenfassungSomatoforme Störungen sind Krankheitsbilder, bei denen die Patienten über körperliche Beschwerden klagen, ohne dass sich hierfür ein spezifischer pathophysiologischer Prozess finden lässt. Die Ätiopathogenese dieser Erkrankungen ist weitestgehend unbekannt. Neben psychischen Faktoren wird eine Beteiligung neurobiologischer Prozesse diskutiert. Mithilfe der transkraniellen Magnetstimulation (TMS) ist es möglich, neurobiologische Prozesse durch die Erfassung kortikaler Erregbarkeitsparameter in vivo zu detektieren. Auf dieser Technik basierend, wurde das kortikale Exzitabilitätsprofil bei Patienten mit subjektiv empfundener Elektrosensibilität erfasst. Es fand sich im Vergleich zu gesunden alters-und geschlechtsparallelisierten Kontrollen eine Verlängerung der „Cortikalen Silent Period” (CSP) als Ausdruck einer verstärkten inhibitorischen Transmission in kortikal-subkortikalen Schleifensystemen. In Einklang mit neuropsychologischen Daten verweisen diese Ergebnisse auf eine mögliche Störung in der sensorischen Informationsverarbeitung.

An einer reprasentativen Stichprobe (n = 758) der Bevolkerung Regensburgs (Alter 18-64 Jahre) wurde detailliert die 4-Wochen-Pravalenz einer Liste von 36 Beschwerden erhoben, die in der Literatur in einem moglichen Zusammenhang mit der Exposition an elektromagnetische Felder genannt waren. 19 dieser Symptome zeigten eine Pravalenz von mehr als 25% Betroffener. Am haufigsten waren Mattigkeit (67,5%), Tagesmudigkeit (63,5%), Kopfschmerzen (56,3%) und Konzentrationsprobleme (54,9%). Die Beschwerden liesen sich trotz der extremen Heterogenitat (betroffene Organsysteme, Art der Beschwerden) sehr gut auf eine gemeinsame, kontinuierliche latente Variable abbilden. Ein spezifisches Muster von Symptomen im Sinne eines Syndromes von Elektrosensibilitat bei einer kleinen Personengruppe lies sich nicht nachweisen. Die Bedingungen sowohl fur eine Rasch-Skala (dichotomisierte Items) wie fur das Partial-Credit Modell (ordinale Antworten) konnen als erfullt gelten. Die inhaltliche Bedeutung dieser latenten Dimension korperbezogener Beschwerden wurde als Zustand der Demoralisation im Sinne von Frank gedeutet. Personen, die uber EMF-bezogene Beschwerden klagen, oder die ihre Beschwerden auf EMF attribuieren, sollten wegen der weiten Verbreitung dieser Symptome unbedingt differenzialdiagnostisch von demoralisierten Personen unterschieden werden.

In this study, the influence of simultaneous application of anionic salts (AS) and rumen buffer (RB) on the metabolism of dairy cows was examined. Eleven rumen fistulated, non-pregnant and non-lactating dairy cows received equal amounts of one AS (CaCl2 or CaSO4) and one RB (NaHCO3 or KHCO3) via rumen cannula during feeding time over a period of eight days. Before the first application of AS and RB and on day eight of the treatment period, blood, urine and rumen fluid samples were taken. The following parameters were measured: whole blood: pH, base excess, bicarbonate; serum: sodium, potassium, chloride, calcium; urine: pH, net acid base excretion, sodium, potassium, chloride, calcium; rumen fluid: pH. The changes of each parameter were compared via ANOVA. The changes in acid-base balance on day eight were very small, although significant. But p-values showed that the statistical evidence was low. The most changes occurred when NaHCO3 was fed in combination with one of the AS used. In this case a small acidogenic load was seen in blood (p < 0.05), and calcium concentrations increased slightly (p < 0.05). No alkalotic reaction could be detected when any combination of AS and RB were given to the cows. Simultaneous application of AS and RB results in a loss of effectivity of AS. Neither an adequate acidification of blood nor an activation of calcium metabolism occurred. In feed ration for cows in the last weeks of pregnancy, rumen buffer must not be fed, if anionic salts are given for prevention of parturient paresis.

Somatoform disorders are characterised by patients suffering from multiple somatic complaints without an underlying pathophysiological process sufficiently explaining these symptoms. The etiology of these disorders is largely unknown. Besides psychological factors neurobiological processes might be involved. Using transcranial magnetic stimulation (TMS), neurobiological processes can be detected in vivo by measuring parameters of cortical excitability. Based on these technique, parameters of cortical exitability were measured in subjectively electrosensible patients. Compared to healthy age- and gender-matched controls, the "cortical silent period" (CSP) was prolonged in these patients indicating an enhanced inhibitory neurotransmission in cortical-subcortical loops. In line with neuropsychological data these results point to potential disturbances in the cortical processing of sensory information.

Transcranial magnetic stimulation of the dorsolateral prefrontal cortex by single pulses of varying field intensities was used to measure thresholds of individual perception and motor response in three groups of subjects: subjectively electrosensitive people, general population controls with a high burden of complaints related to electromagnetic field (EMF) exposure in the literature (highest decile in complaint burden), and general population controls with a low burden of complaints (lowest decile in complaint burden). The major study endpoint was the ability of the subjects to differentiate between real magnetic stimulation and a sham condition. There were no significant differences between groups in the thresholds, neither of detecting the real magnetic stimulus nor in motor response. But the three groups differed significantly in differentiating between stimulation and sham condition, with the subjectively electrosensitive people having the lowest ability to differentiate and the control group with high level of EMF-related complaints having the best ability to differentiate. Differences between groups were mostly due to false alarm reactions in the sham condition reported by subjectively electrosensitives (SES). We found no objective correlate of the self perception of being "electrosensitive." Overall, our experiment does not support the hypothesis that subjectively electrosensitive patients suffer from a physiological hypersensitivity to EMFs or stimuli. Further research should focus on disposing factors explaining the unspecific sensory hyperresponsiveness of subjectively electrosensitive subjects.

Two cases of zinc deficiency in dairy goats from different flocks and not associated with a zinc-deficient diet are described. Hard, dry, hyperkeratotic skin, hair loss and pruritus especially prominent on the back, legs, udder, face and ears were the most common clinical signs. Skin biopsy findings revealed a mixture of orthokeratotic and parakeratotic hyperkeratosis. On initial examination, serum zinc concentrations were low in both goats (461 microg L(-1) and 521 microg L(-1), respectively). Although mild skin lesions persisted during the early stages of zinc supplementation, skin lesions completely resolved after prolonged oral zinc supplementation. Withdrawal of zinc supplementation resulted in re-appearance of lesions in both animals. Case 2 gave birth to two kids, one of which showed mild skin lesions at 8 months of age together with a low serum zinc concentration (434 microg L(-1)), suggestive of hereditary zinc malabsorption. The other kid remained free of skin lesions and had a serum zinc concentration (530 microg L(-1)) within the normal range. On the basis of historical and clinical findings, the cases presented here more closely resemble Syndrome 1 hereditary zinc deficiency as seen in Nordic dog breeds rather than other zinc deficiency conditions seen in other species. It is suggested that zinc deficiency in these goats was due to hereditary malabsorption of dietary zinc. This is the first descriptive study of this condition in goats. Life-long zinc supplementation may be necessary in such patients.