Biomedical subjects

Lena Hillert

Publications and source records attributed to Lena Hillert.

8 recordsLinked to original sources

PubMed2007

Investigation of electric current perception thresholds of different EHS groups.

An increasing number of persons with health symptoms of unclear origin take refuge in the hypothesis that they suffer from electromagnetic hypersensitivity (EHS). So far EHS is not an accepted diagnosis and there is no validated test to verify the proposed relationship between electromagnetic fields and symptoms. Groups reporting EHS are very heterogeneous but share a belief that they have an increased sensitivity to electromagnetic fields. It was studied to which extent a quantitative indicator for electrosensitivity, the electric current perception threshold, and its variability coefficient, depend on the recruitment strategy for self-declared hypersensitive persons. Individual electrosensitivity was investigated by provocation of the lower arms to directly coupled 50 Hz electric currents. Self-declared EHS persons were selected from members of a self aid group, from responders to a newspaper call, and from persons actively asking for investigations in their search for help. It turned out that quantitative electrosensitivity was quite different among the three groups. It is interesting that the members of the EHS self aid group exhibit a considerable overlap with general population sample. Pooled together it could be shown that hypersensitive persons as a group differ significantly from the general population sample, however with a pronounced overlap with the normal range. It can be concluded that EHS groups are very inhomogeneous and contain numerous persons with no increased ability to perceive low frequency electric or magnetic fields. This investigation shows the importance of the study design, in particular of the recruitment strategies of EHS persons for the final outcome.

Adult↗

PubMed2007

Odor processing in multiple chemical sensitivity.

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.

Adult↗

PubMed2006

Call-related factors influencing output power from mobile phones.

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.

Cell Phone↗

PubMed2005

915 MHz microwaves and 50 Hz magnetic field affect chromatin conformation and 53BP1 foci in human lymphocytes from hypersensitive and healthy persons.

We used exposure to microwaves from a global system for mobile communication (GSM) mobile phone (915 MHz, specific absorption rate (SAR) 37 mW/kg) and power frequency magnetic field (50 Hz, 15 muT peak value) to investigate the response of lymphocytes from healthy subjects and from persons reporting hypersensitivity to electromagnetic field (EMF). The hypersensitive and healthy donors were matched by gender and age and the data were analyzed blind to treatment condition. The changes in chromatin conformation were measured with the method of anomalous viscosity time dependencies (AVTD). 53BP1 protein, which has been shown to colocalize in foci with DNA double strand breaks (DSBs), was analyzed by immunostaining in situ. Exposure at room temperature to either 915 MHz or 50 Hz resulted in significant condensation of chromatin, shown as AVTD changes, which was similar to the effect of heat shock at 41 degrees C. No significant differences in responses between normal and hypersensitive subjects were detected. Neither 915 MHz nor 50 Hz exposure induced 53BP1 foci. On the contrary, a distinct decrease in background level of 53BP1 signaling was observed upon these exposures as well as after heat shock treatments. This decrease correlated with the AVTD data and may indicate decrease in accessibility of 53BP1 to antibodies because of stress-induced chromatin condensation. Apoptosis was determined by morphological changes and by apoptotic fragmentation of DNA as analyzed by pulsed-field gel electrophoresis (PFGE). No apoptosis was induced by exposure to 50 Hz and 915 MHz microwaves. In conclusion, 50 Hz magnetic field and 915 MHz microwaves under specified conditions of exposure induced comparable responses in lymphocytes from healthy and hypersensitive donors that were similar but not identical to stress response induced by heat shock.

Adult↗

PubMed2005

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

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 (gamma-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/gamma-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.

Adult↗

PubMed2003

Multiple chemical sensitivity in male painters; a controlled provocation study.

The purpose of the present study was to examine whether male painters reporting multiple chemical sensitivity (MCS) differ from their matched controls (male painters without such sensitivity) during controlled chamber challenges to singular and mixtures of odorous chemicals with respect to: (1) Subjective rating of symptoms (i.e., symptoms related to central nervous system (CNS) and symptoms related to irritation) and sensations of smell elicited by low-level chemical exposures. (2) Changes in serum prolactin and cortisol levels, changes in nasal cavity and eye redness as a result of the various exposures. Moreover, background assessments were made regarding mental well-being, sense of coherence (SOC) as well as state of anxiety and depression in both groups. The MCS and control group consisted of 14 and 15 male painters respectively. Regarding background assessments of mental well-being, anxiety, depression and SOC, statistically significant differences were obtained between painters with MCS and their controls. During the controlled chamber challenges, neither difference regarding sensations of smell nor development of CNS related symptoms were seen between MCS and control group. In contrast, subjective rating of symptoms related to irritation (i.e., eyes, nose, throat, skin, and breathing difficulties) was significant higher in subjects with MCS. No differences between the groups as a result of the different exposures were seen concerning nasal cavity, eye redness and serum cortisol levels. However, a trend (P = 0.056) between the groups was measured regarding a decline of serum prolactin levels in the MCS group. This is a relatively small study with a limited number of volunteers; and no definitive conclusions can be drawn concerning the above findings. But it is the first controlled challenge study that incorporates similarly exposed groups (painters) recruited from a community rather than from a clinical population.

Adult↗

PubMed2002

Environmental illness--effectiveness of a salutogenic group-intervention programme.

AIMS: Hypersensitivity to electricity (HE) is a common form of reported environmental illness in Sweden. Functional somatic symptoms has been attributed to exposure to activated electrical equipment, but no causal relationship to electromagnetic fields has been proved. In many cases, traumatic life events and psychosocial stress can be identified, but patients often reject psychological explanations. This study evaluates the effectiveness of a new short-term group-intervention programme. METHODS: A multidisciplinary team developed a short-term group-intervention programme, with a salutogenic approach that focuses on somatic and psychological reactions. Twenty-two patients (14 women and 8 men) who reported HE participated in eight weekly sessions of group meetings and physiotherapy. The effect of the programme was evaluated with regard to changes in work capacity, subjective well-being, coping ability, body awareness and physical fitness. RESULTS: Contrary to our hypothesis physical fitness was not remarkably low. Muscular tension was reduced and body awareness increased but no significant change in symptoms was observed. Individual differences in progress were observed. Fourteen patients chose to continue with psychotherapy or physiotherapy. CONCLUSIONS: Participants accepted the programme very well. One important result was identification of underlying contributing factors and motivation for further therapy. A multidisciplinary group-intervention programme with a salutogenic approach might be a useful approach to patients with medically unexplained symptoms in primary healthcare.

Adaptation, Psychological↗

PubMed2002

Prevalence of self-reported hypersensitivity to electric or magnetic fields in a population-based questionnaire survey.

OBJECTIVES: The prevalence of medically unexplained symptoms attributed to exposure to electromagnetic fields is still largely unknown. Previous studies have investigated reported hypersensitivity to electricity in selected groups recruited from workplaces or outpatient clinics. The aim of this study was to estimate the prevalence of self-reported hypersensitivity to electric or magnetic fields in the general population and to describe characteristics of the group reporting such hypersensitivity with regard to demographics, other complaints, hypersensitivities, and traditional allergies. METHODS: A cross-sectional questionnaire survey was conducted in 1997 among 15,000 men and women between 19 and 80 years of age in Stockholm County. The response rate was 73%. RESULTS: One and a half percent of the respondents reported hypersensitivity to electric or magnetic fields. Prevalence was highest among women and in the 60- to 69-year age group. The hypersensitive group reported all symptoms, allergies, and other types of hypersensitivities included in the survey (as well as being disturbed by various factors in the home) to a significantly greater extent than the rest of the respondents. No specific symptom profile set off the hypersensitive group from the rest of the respondents. CONCLUSIONS: The results should be interpreted with caution. But they suggest that there is widespread concern among the general population about risks to health posed by electric and magnetic fields. More research is warranted to explore ill health among people reporting hypersensitivity to electric or magnetic fields.

Adult↗