An in silico analysis of neuromodulation for pain relief: Determining the role of classical electrodynamics.

There has been ongoing debate about the efficacy and mechanism of action of neuromodulation devices in pain relief applications. It has recently been suggested that both issues may be resolved if electromagnetic theory is incorporated into the understanding and application of this technology, and we therefore undertook an in silico analysis to further explore this idea. We created a CAD replication of a standard neuromodulation electrode array with a generic linear 3/6 mm 8-contact lead, developed a parameterized algorithmic model for the pulse delivered by the device and assigned material properties to biologic media to accurately reflect their electromagnetic properties.

Solid phase partitioning of metals in managed retreat soils: field changes over the first year of tidal inundation.

Sequential extraction methods were used to determine the effect of saline inundation on partitioning behaviour of metals in soils at Orplands Managed Retreat site, Essex, UK. A suite of metals (Al, Ca, Cr, Cu, Fe, K, Li, Mn, Ni, Pb and Zn) were analysed in sequential extracts from samples of soil cores extracted immediately before breaching of sea walls in 1995 and 1 year after. Generally, partitioning of most metals was dominated by associations with the residual fraction and an absence of associations with the exchangeable fraction indicating a relatively uncontaminated environment.

Life-span changes in EEG spectral amplitude, amplitude variability and mean frequency.

Objectives: The objectives were to assess life-span alterations in intrasubject variability of EEG spectral amplitudes and in amplitude and mean frequency computed from spectral amplitude profiles.

Methods: EEG was recorded from the central and occipital scalp of 222 healthy males aged 4 to 90 years. Amplitude spectral profiles derived from FFT procedures provided data for the computation of amplitude variability (ampCV), absolute and relative amplitude and mean frequency for each of five spectral bands.

Poikilodermatous and verrucous mycosis fungoides.

Mycosis fungoides (MF) is a cutaneous lymphoma of presumed T-helper cell origin. It usually presents with patches and infiltrated plaques, but a wide range of atypical forms have also been described. We report a 48-year-old man who had a 2-year history of a pruritic, warty plaque on the right palm with surrounding poikilodermatous changes.

Life span changes in electrophysiological measures of inhibition.

Three electrophysiological findings which provide suggestive evidence of weakened inhibition in children and the elderly are reviewed. First, compared to young adults, electrophysiological recordings from old adults show a greater incidence of EEG alpha in anterior cortical areas and of somatosensory evoked potentials in occipital areas, and a reduction in heterogeneity of EEG and ERP activity across recording sites. These findings suggest a relative weakening of central inhibition in old age and a loss of functional independence of cortical centers.

Local healthcare planning in rural southwestern Ontario.

In rural areas, local health and social services are often planned and developed by members of the community, the hospital and community agencies acting together. This system is a web of informal ties that, relying heavily on volunteer commitment, provides programs that aptly fit the local situation. In this article, the authors show how this functions in the Ontario community surrounding Palmerston and District Hospital, and offer a suggestion for the improved support of this system.

Severe case of pemphigoid gestationis with unusual target antigen.

We report a severe case of pemphigoid gestationis (PG) with an unusual target antigen. The patient developed a severe itchy macular rash on the abdomen during her fifth pregnancy, at 38 weeks' gestation. The disease persisted for 8 months post-partum, and could only be controlled with high doses of systemic corticosteroids and dapsone.

The effects of videogame playing on neuropsychological performance of elderly individuals.

To determine the effects of sensory-perceptual stimulation (videogame playing) on neuropsychological performance, measures of reaction time (RT), visual sensitivity, cognition, and affect were obtained from 60 healthy 60- to 79-year-old individuals before and after their 11-week participation in videogame (VG) playing, movie viewing, or as controls. Only RT demonstrated an activity specific change, being significantly faster at posttesting for the VG subjects. The RT results indicate that the central nervous system of elderly people can be modified by activation procedures.

A prospective study on intradialytic symptoms associated with reuse of hemodialyzers.

The benefits and disadvantages of hemodialyzer reuse is controversial. While biochemical data have suggested potential benefits from reuse, there is dispute over the clinical impact on the patient. Limited data show that reuse is associated with less intradialytic symptoms compared to first use.

Aerobic capacity of older adults: a training study.

The effects of a four month aerobic conditioning program on heart rate, blood pressure, maximal oxygen consumption (VO2max), and physical work capacity of 55-70 year old sedentary individuals were evaluated. Twenty-eight men and women participated in either 4 months of supervised fast walking or jogging at a prescribed target heart rate or stretching exercises for one hour, three days per week. Gains in VO2max (ml/kg/min) obtained during a Balke maximal treadmill test in aerobic and exercise control subjects were 27% and 9%, respectively.

Age and fitness effects on EEG, ERPs, visual sensitivity, and cognition.

Measures of EEG, event-related potentials (ERPs), visual sensitivity, and cognition were obtained from 30 young (20-31 years) and 30 older (50-62 years) healthy men. Age groups were evenly divided between subjects with low and high fitness levels documented by VO2max during a maximal exercise test. Age comparisons revealed that, compared to young adults, the older men had reduced visual sensitivity, delayed ERP latencies, greater homogeneity of EEG activity across recording sites, more positive visual-evoked potential (VEP) amplitude-intensity (A/I) slope, and poorer performance on a battery of neurocognitive tests.

Self-efficacy in alcoholics: clinical validation of the Situational Confidence Questionnaire.

Recent theory and empirical data suggest that self efficacy plays an important role in resistance to relapse for substance abusers. This study investigated the validity of the Situational Confidence Questionnaire (SCQ), a new instrument designed to measure self-efficacy expectations in purported high-risk drinking situations. The SCQ was administered to 46 short-term sober (STS) and 25 long-term sober (LTS) alcoholics.

P3 latency and symbol digit performance correlations in aging.

Relationships among age, P3 latency, and Symbol Digit Modalities Test (SDMT) performance were investigated for 172 subjects ranging from 20 to 79 years. Age-related increases in P3 latency were most evident for older normal subjects (greater than 55 years) and for a subset of subjects with low physical fitness levels, but were negligible for a subset of subjects with high physical fitness levels. A similar relationship was found between age and SDMT.

Cardio-respiratory fitness of young and older active and sedentary men.

Physiological profiles are described for 30 healthy young (20-31 years) and 30 healthy older (50-62 years) men. Half of the individuals in each group reported that during the previous five years they participated frequently in strenuous physical exercises; the other half reported sedentary lifestyles. A treadmill exercise test was used to determine maximal aerobic power (VO2 max).

Neuropsychological performance of young nondrinkers, social drinkers, and long- and short-term sober alcoholics.

Neuropsychological performance of 23-42-year-old males with diverse drinking histories was assessed. Comparisons were made among nondrinkers, social drinkers, short-term sober (less than 30 days) alcoholics and long-term sober (greater than 30 days) alcoholics. Results of these comparisons provided little support for the notion that neurotoxic effects of chronic alcohol consumption are directly related to cognitive impairment.

Self-efficacy, standards, and abstinence violation: a comparison between newly sober and long-term sober alcoholics.

Recent theory and empirical data suggest that self-efficacy plays an important role in resistance to relapse for substance abusers. Another key in the relapse process, according to Marlatt and Gordon (1985), is the abstinence violation effect, which comprises self-attribution for failure and affective reaction to violation of self-imposed standards. The combination of unrealistically high standards and low self-efficacy for following those standards may potentiate the risk for relapse.

EEG, visually evoked and event related potentials in young abstinent alcoholics.

EEG, visually evoked potentials (VEP), and event related potentials (P300) were recorded from 60 males aged 25-40 (20 abstinent alcoholics, 20 social drinkers, and 20 lifetime nondrinkers). Alcoholics were at least 1 month abstinent, medication free, and neuropsychologically normal. Residual effects of alcohol abuse were not detected in EEG power and cortical coupling analyses, or VEP amplitude, latency, and amplitude/intensity slope measures.

Behavioral effects of chronic exposure to 0.5 mW/cm2 of 2,450-MHz microwaves.

Adult male, Long-Evans rats were exposed 7 h a day for 90 days to continuous wave (CW) 2,450-MHz microwaves at an average power density of 0.5 mW/cm2. Exposures were in a monopole-above-ground radiation chamber with rats in Plexiglas cages.

Absorption of microwave radiation by the anesthetized rat: electromagnetic and thermal hotspots in body and tail.

Anatomic variability in the deposition of radiofrequency electromagnetic energy in mammals has been well documented. A recent study [D'Andrea et al., 1985] reported specific absorption rate (SAR) hotspots in the brain, rectum and tail of rat carcasses exposed to 360- and to 2,450-MHz microwave radiation.

Intermittent exposure of rats to 2450 MHz microwaves at 2.5 mW cm2: behavioral and physiological effects.

Long-Evans male adult rats were intermittently exposed for 14 weeks to continuous wave (CW) 2450-MHz microwaves at an average power density of 2.5 mW/cm2. The mean specific absorption rate was 0.

Pattern reversal evoked potentials: age, sex and hemispheric asymmetry.

Binocular pattern reversal evoked potentials (PREPs) and EEG power were recorded bilaterally from occipital scalp of 50 boys and 50 girls aged 5-14. PREP latency was unaffected by either age or gender. Amplitudes, however, were consistently larger for girls than boys, with differences diminishing by adolescence.