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Dive into the research topics where Lena Hillert is active.

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Featured researches published by Lena Hillert.


Environmental Health Perspectives | 2005

Microwaves from GSM mobile telephones affect 53BP1 and gamma-H2AX foci in human lymphocytes from hypersensitive and healthy persons

Eva Markova; Lena Hillert; Lars Malmgren; Bertil Persson; Igor Belyaev

The data on biologic effects of nonthermal microwaves (MWs) from mobile telephones are diverse, and these effects are presently ignored by safety standards of the International Commission for Non-Ionizing Radiation Protection (ICNIRP). In the present study, we investigated effects of MWs of Global System for Mobile Communication (GSM) at different carrier frequencies on human lymphocytes from healthy persons and from persons reporting hypersensitivity to electromagnetic fields (EMFs). We measured the changes in chromatin conformation, which are indicative of stress response and genotoxic effects, by the method of anomalous viscosity time dependence, and we analyzed tumor suppressor p53-binding protein 1 (53BP1) and phosphorylated histone H2AX (γ-H2AX), which have been shown to colocalize in distinct foci with DNA double-strand breaks (DSBs), using immunofluorescence confocal laser microscopy. We found that MWs from GSM mobile telephones affect chromatin conformation and 53BP1/γ-H2AX foci similar to heat shock. For the first time, we report here that effects of MWs from mobile telephones on human lymphocytes are dependent on carrier frequency. On average, the same response was observed in lymphocytes from hypersensitive and healthy subjects.


Human Brain Mapping | 2007

Odor processing in multiple chemical sensitivity.

Lena Hillert; Vildana Musabasic; Hans Berglund; Carolina Ciumas; Ivanka Savic

Multiple chemical sensitivity (MCS) is characterized by somatic distress upon exposure to odors. As in other idiopathic environmental intolerances, the mechanisms behind the reported hypersensitivity are unknown. Using the advantage of the well‐defined trigger (odor), we investigated whether subjects with MCS could have an increased odor‐signal response in the odor‐processing neuronal circuits. Positron emission tomography (PET) activation studies with several different odorants were carried out in 12 MCS females and 12 female controls. Activation was defined as a significant increase in regional cerebral blood flow (rCBF) during smelling of the respective odorant compared to smelling of odorless air. The study also included online measurements of respiratory frequency and amplitude and heart rate variations by recording of R wave intervals (RR) on the surface electrocardiogram. The MCS subjects activated odor‐processing brain regions less than controls, despite the reported, and physiologically indicated (decreased RR interval) distress. In parallel, they showed an odorant‐related increase in activation of the anterior cingulate cortex and cuneus‐precuneus. Notably, the baseline rCBF was normal. Thus, the abnormal patterns were observed only in response to odor signals. Subjects with MCS process odors differently from controls, however, without signs of neuronal sensitization. One possible explanation for the observed pattern of activation in MCS is a top‐down regulation of odor‐response via cingulate cortex. Hum. Brain Mapp, 2007.


Journal of Psychosomatic Research | 1999

Hypersensitivity to electricity : Working definition and additional characterization of the syndrome

Lena Hillert; Birgitta Kolmodin Hedman; Erik Söderman; Bengt B. Arnetz

Those who believe that electric appliances trigger adverse symptoms have coined the label hypersensitivity to electricity. Scientific research has not been able to identify a direct link between electromagnetic fields and symptoms, and no diagnostic criteria exist. Groups with reported hypersensitivity are very heterogeneous. A need exists for an operational working definition and improved characterization of groups. We report an investigation of symptoms and risk indicators associated with reported hypersensitivity to electricity-based on a survey at a high-technology, multinational telecommunications corporation. Comparisons are also made with patients referred to a university department of occupational and environmental health. No association was found between specific psychosocial work characteristics nor personal traits and hypersensitivity to electricity. We present skin and neurovegetative symptom indices. Results indicate that skin, and not neurovegetative symptoms, characterize the syndrome, at least during the first years of illness. For characterization, we propose a set of dimensions, including triggering factors, behavior, and duration of symptoms.


Bioelectromagnetics | 2011

Do people with idiopathic environmental intolerance attributed to electromagnetic fields display physiological effects when exposed to electromagnetic fields? A systematic review of provocation studies.

G. James Rubin; Lena Hillert; Rosa Nieto-Hernandez; Eric van Rongen; Gunnhild Oftedal

Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) is a controversial illness in which people report symptoms that they believe are triggered by exposure to EMF. Double-blind experiments have found no association between the presence of EMF and self-reported outcomes in people with IEI-EMF. No systematic review has assessed whether EMF exposure triggers physiological or cognitive changes in this group. Using a systematic literature search, we identified 29 single or double-blind experiments in which participants with IEI-EMF were exposed to different EMF levels and in which objectively measured outcomes were assessed. Five studies identified significant effects of exposure such as reduced heart rate and blood pressure, altered pupillary light reflex, reduced visual attention and perception, improved spatial memory, movement away from an EMF source during sleep and altered EEG during sleep. In most cases, these were isolated results that other studies failed to replicate. For the sleep EEG findings, the results reflected similar changes in the IEI-EMF participants and a non-IEI-EMF control group. At present, there is no reliable evidence to suggest that people with IEI-EMF experience unusual physiological reactions as a result of exposure to EMF. This supports suggestions that EMF is not the main cause of their ill health.


Bioelectromagnetics | 2011

Sleep after mobile phone exposure in subjects with mobile phone‐related symptoms

Arne Lowden; Torbjörn Åkerstedt; Michael Ingre; Clairy Wiholm; Lena Hillert; Niels Kuster; Jens P. Nilsson; Bengt B. Arnetz

Several studies show increases in activity for certain frequency bands (10-14 Hz) and visually scored parameters during sleep after exposure to radiofrequency electromagnetic fields. A shortened REM latency has also been reported. We investigated the effects of a double-blind radiofrequency exposure (884 MHz, GSM signaling standard including non-DTX and DTX mode, time-averaged 10 g psSAR of 1.4 W/kg) on self-evaluated sleepiness and objective EEG measures during sleep. Forty-eight subjects (mean age 28 years) underwent 3 h of controlled exposure (7:30-10:30 PM; active or sham) prior to sleep, followed by a full-night polysomnographic recording in a sleep laboratory. The results demonstrated that following exposure, time in Stages 3 and 4 sleep (SWS, slow-wave sleep) decreased by 9.5 min (12%) out of a total of 78.6 min, and time in Stage 2 sleep increased by 8.3 min (4%) out of a total of 196.3 min compared to sham. The latency to Stage 3 sleep was also prolonged by 4.8 min after exposure. Power density analysis indicated an enhanced activation in the frequency ranges 0.5-1.5 and 5.75-10.5 Hz during the first 30 min of Stage 2 sleep, with 7.5-11.75 Hz being elevated within the first hour of Stage 2 sleep, and bands 4.75-8.25 Hz elevated during the second hour of Stage 2 sleep. No pronounced power changes were observed in SWS or for the third hour of scored Stage 2 sleep. No differences were found between controls and subjects with prior complaints of mobile phone-related symptoms. The results confirm previous findings that RF exposure increased the EEG alpha range in the sleep EEG, and indicated moderate impairment of SWS. Furthermore, reported differences in sensitivity to mobile phone use were not reflected in sleep parameters.


Current Pain and Headache Reports | 2010

Migraine and Olfactory Stimuli

Christina Sjöstrand; Ivanka Savic; Eva Laudon-Meyer; Lena Hillert; Karin Lodin; Elisabet Waldenlind

Migraine patients often report intolerance to odours. Migraineurs report odours may trigger attacks, that they experience osmophobia during attacks, and olfactory hypersensitivity between attacks. In this paper we discuss olfactory mechanisms in migraine. We also present data from a pilot questionnaire study in a group of young women diagnosed with migraine. The study results confirm that hypersensitivity to odour is a common feature in women with migraine. Migraine pathophysiology likely explains this particular vulnerability. We discuss these pathophysiologic mechanisms and hypotheses relating odour intolerances and migraine.


Psychotherapy and Psychosomatics | 1998

Cognitive Behavioural Therapy for Patients with Electric Sensitivity – a Multidisciplinary Approach in a Controlled Study

Lena Hillert; Birgitta Kolmodin Hedman; Barbro F. Dölling; Bengt B. Arnetz

Background: Electric sensitivity is a syndrome that still lacks diagnostic criteria and proven aetiology. The suffering of afflicted persons motivates development and evaluation of effective handling and treatments. The aim of the study was to evaluate the effect of cognitive behavioural therapy in patients with electric sensitivity. Methods: Cognitive behavioural treatment, as part of a multidisciplinary treatment package for patients with electric sensitivity, was evaluated in a controlled trial. Ten patients who received treatment were compared to 12 controls. Outcome measures included different dimensions such as symptoms, beliefs, behaviour, and biochemical measurements of stress-related variables. All outcome measures were collected prior to the study, post-treatment, and after an additional 6-month follow-up. Results: The therapy group rated their electric sensitivity as significantly lower than did the control group at the 6-month follow-up, and reduction of self-rated discomforts from triggering factors was significant in the therapy group. There were no systematic changes in the biochemical variables. The symptom indices were significantly reduced over time, and ability to work continued to be good in both groups. Conclusion: The prognosis for this syndrome is good with early intervention and cognitive therapy may further reduce the perceived hypersensitivity. This may have important implications on handling of patients with electric sensitivity.


Journal of Exposure Science and Environmental Epidemiology | 2006

Call-related factors influencing output power from mobile phones

Lena Hillert; Anders Ahlbom; David Neasham; Maria Feychting; Lars Jarup; Roshan Navin; Paul Elliott

Mobile phone use is increasing but there is also concern for adverse health effects. Well-designed prospective studies to assess several health outcomes are required. In designing a study of mobile phone use, it is important to assess which factors need to be considered in classifying the exposure to radiofrequency fields (RF). A pilot study was performed in Sweden and in the UK 2002 to 2003 to test the feasibility of recruiting a cohort of mobile phone users from a random population sample and from mobile phone subscription lists for a prospective study. As one part of this pilot study, different factors were evaluated regarding possible influence on the output power of the phones. By local switch logging, information on calls made from predefined subscriptions or dedicated handsets were obtained and the output power of phones during calls made indoors and outdoors, in moving and stationary mode, and in rural as well in urban areas were compared. In this experiment, calls were either 1, 1.5 or 5 min long. The results showed that high mobile phone output power is more frequent in rural areas whereas the other factors (length of call, moving/stationary, indoor/outdoor) were of less importance. Urban and rural area should be considered in an exposure index for classification of the exposure to RF from mobile phones and may be assessed by first base station during mobile phone calls or, if this information is not available, possibly by using home address as a proxy.


Piers Online | 2007

The Effects of 884 MHz GSM Wireless Communication Signals on Self-reported Symptom and Sleep (EEG)- An Experimental Provocation Study

Bengt B. Arnetz; Torbjörn Åkerstedt; Lena Hillert; Arne Lowden; Niels Kuster; Clairy Wiholm

In the current study we assessed possible efiects of prolonged (3 hours) exposure to 884MHz GSM wireless communication signals on self-reported symptoms, cognitive function, and electroencephalographically (EEG) recorded sleep. The study group consisted of 36 women and 35 men. Twenty-two women and sixteen men reported symptoms they speciflcally related to mobile phone use (SG). The rest of the participants reported no mobile phone-related symptoms (NG). Potential participants volunteering for the study were evaluated by physicians, including some biochemical assessments, to rule out medical conditions that could interfere with study variables of interest. Once selected, participants spent three difierent sessions in the laboratory. The ha- bituation session was followed by two subsequent sessions. In these subsequent sessions, subjects were either exposed to sham exposure (sham) or 884MHz GSM wireless communication signals for 3 hours (an average of 1.4W/kg including periods of DTX and Non-DTX. Exposure directed to the left hemisphere). Data was collected before, during and following the exposure/sham ses- sions. Data collected included self-reported symptoms, including headache, cognitive function, mood, and electroencephalographic recordings. During actual exposure, as compared to sham exposure, sleep initiated one hour after exposure was afiected. There was a prolonged latency to reach the flrst cycle of deep sleep (stage 3). The amount of stage 4 sleep was also decreased in exposed subjects. NG subjects reported more headaches during exposures vs. sham exposure. Neither group (SG and NG) was able to detect the true exposure status more frequently than by chance alone. The study indicates that during laboratory exposure to 884MHz wireless signals, components of sleep, believed to be important for recovery from daily wear and tear, are adversely afiected. Moreover, participants that otherwise have no self-reported symptoms related to mobile phone use, appear to have more headaches during actual radiofrequency exposure as compared to sham exposure. However, subjects were not able to detect the true exposure status more often than would have been expected by statistical chance alone. Additional self-reported flndings, biochemical, performance and electrophysiological data are currently being analyzed. Possible health implications from the flndings will also be further explored.


PLOS ONE | 2013

Women with Multiple Chemical Sensitivity Have Increased Harm Avoidance and Reduced 5-HT1A Receptor Binding Potential in the Anterior Cingulate and Amygdala

Lena Hillert; Hristina Jovanovic; Fredrik Åhs; Ivanka Savic

Multiple chemical sensitivity (MCS) is a common condition, characterized by somatic distress upon exposure to odors. As in other idiopathic environmental intolerances, the underlying mechanisms are unknown. Contrary to the expectations it was recently found that persons with MCS activate the odor-processing brain regions less than controls, while their activation of the anterior cingulate cortex (ACC) is increased. The present follow-up study was designed to test the hypotheses that MCS subjects have increased harm avoidance and deviations in the serotonin system, which could render them intolerant to environmental odors. Twelve MCS and 11 control subjects, age 22–44, all working or studying females, were included in a PET study where 5-HT1A receptor binding potential (BP) was assessed after bolus injection of [11C]WAY100635. Psychological profiles were assessed by the Temperament and Character Inventory and the Swedish universities Scales of Personality. All MCS and 12 control subjects were also tested for emotional startle modulation in an acoustic startle test. MCS subjects exhibited significantly increased harm avoidance, and anxiety compared to controls. They also had a reduced 5-HT1A receptor BP in amygdala (p = 0.029), ACC (p = 0.005) (planned comparisons, significance level 0.05), and insular cortex (p = 0.003; significance level p<0.005 with Bonferroni correction), and showed an inverse correlation between degree of anxiety and the BP in the amygdala (planned comparison). No group by emotional category difference was found in the startle test. Increased harm avoidance and the observed changes in the 5-HT1A receptor BP in the regions processing harm avoidance provides a plausible pathophysiological ground for the symptoms described in MCS, and yields valuable information for our general understanding of idiopathic environmental intolerances.

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Bengt B. Arnetz

Michigan State University

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Niels Kuster

École Polytechnique Fédérale de Lausanne

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Yngve Hamnerius

Chalmers University of Technology

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Paul Elliott

Imperial College London

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