Stroke in parents who lost a child: a nationwide follow-up study in Denmark

The association between psychological stress and stroke remains uncertain. We therefore examined whether or not one of the most extreme psychological stressors, the death of a child, was associated with the risk of stroke in a nationwide population-based follow-up study. All 21,062 parents who lost a child in Denmark during 1980-1996 were compared with 293,745 parents who had not lost a child. The overall adjusted relative risk (RR) of stroke was 1.00 (95% CI = 0.83-1.20) among the exposed after up to 18 years of follow-up. The RRs for fatal stroke and nonfatal stroke were 0.69 (95% CI = 0.37-1.26) and 1.03 (95% CI = 0.85-1.24), respectively. The RRs for hemorrhagic and nonhemorrhagic stroke were 1.02 (95% CI = 0.77-1.36) and 0.94 (95% CI = 0.74-1.20), respectively. The risk of stroke did not differ irrespective of whether the death of the child was unexpected or not. The death of a child was not associated with any substantially increased risk of stroke in the bereaved parents.     

Decreased production of reactive oxygen species by blood monocytes caused by clozapine correlates with EEG slowing in schizophrenic patients

We have earlier reported an increased theta-power value in clozapine (CLO)-treated patients with schizophrenia, nonresponsive to conventional antipsychotics. We also found that the decrease in the production of reactive oxygen species (ROS), induced by CLO, by peripheral blood monocytes (MO) of these patients correlates with clinical improvement. MO share the capability of ROS production with their more mature descendants, microglia of the brain. We hypothesized that the CLO-related changes in peripheral blood MO might be related to a parallel process in microglia and thus be reflected in brain activity. In those 8 patients for whom both QEEG and MO data were available, we explored possible relationships between these parameters. A clear-cut correlation between ROS production (R(2) = 0.929, p < 0.05) for nonstimulated MO, and (R(2) = 0.907, p < 0.001) for stimulated MO and theta-power values in the central frontal electrode (F(z)) was found. It is intriguing to speculate that the EEG slowing is a result of the modulatory action of the activated microglial cells in the central nervous system via production of ROS or cytokines or both. However, this proposition has to be confirmed by future research.     

Growth hormone-insulin-like growth factor-1 axis,leptin and sleep in anorexia nervosa patients

The present study characterizes the relationships between severe malnutrition, sleep, growth hormone-insulin-like growth factor-1 (GH-IGF-1) axis, and leptin levels in anorexia nervosa (AN) patients before and after weight gain. Eleven restricting-type anorectic females (mean age = 19.7 years) with severe starvation state [mean body mass index (BMI) = 13.3] were studied using polysomnography and spectral power analysis. The hormone levels were measured in the morning after sleep recording. Eleven normal-weight, age- and gender-matched healthy volunteers without a history of any eating disorder served as controls. After nutritional treatment for about 2 months (65.7 +/- 6.4 days), sleep examinations and blood tests were repeated. At this stage, the study group consisted of 5 patients (mean BMI = 15.6). Higher IGF-1 and leptin levels were associated with longer and deeper sleep among anorectics. The sleep parameters including the percentages of stage 1 sleep and SWS as well as IGF-1 tended to normalize after only limited weight gain. Sleep disturbances in anorectics may be mediated through changes in the levels of the GH-IGF-1 axis hormones, as well as the levels of leptin.     

Differential regulation of 5' splice variants of the glutamate transporter EAAT2 in an in vivo model of chemical hypoxia induced by 3-nitropropionic acid

Defective glutamate uptake has been implicated as a pathogenic event of neuronal damage related to cerebral ischemia and hypoxia. In several models of ischemia-hypoxia, a reduced immunoreactivity and altered RNA expression of excitatory amino acid transporter 2 (EAAT2), the major excitatory amino acid transporter, have been reported. However, the gene regulation of EAAT2 under these conditions is incompletely understood. In this study, we investigated alternative splicing of EAAT2 in an in vivo mouse model of chemical hypoxia as induced by 3-nitropropionic acid (3-NP). The neurotoxin 3-NP is an inhibitor of mitochondrial energy production. Furthermore, it is known to inhibit glutamate reuptake directly, representing at least one of the mechanisms responsible for 3-NP-induced neurodegeneration. Here we report an expression analysis of five known (mEAAT2/5UT1-5) and two novel (mEAAT2/5UT6, -7) 5' splice variants of EAAT2 using semiquantitative PCR. The RNA expression was studied at 2, 12, 24, 48, and 72 hr and 7 days after 3-NP administration. mEAAT2/5UT4 and mEAAT2/5UT5 were up-regulated in the frontal cortex and down-regulated in the hippocampus 12-72 hr after chemical hypoxia. In the cerebellum, there was an increased expression of mEAAT2/5UT4 and a down-regulation of mEAAT2/5UT5. mEAAT2/5UT3 show a different regional expression pattern, being regulated in the cerebellum only. mEAAT2/5UT1-7 encoded distinct 5' regulatory sequences, including conserved elements of translational control. It is easily conceivable that expression alterations of 5' splice variants of EAAT2 are related to glutamate transporter malfunction after chemical hypoxia. Our findings contribute to the hypothesis that RNA splicing events can serve as a molecular mechanism of posthypoxic gene regulation.     

Features indicative of cervical abnormality. A factor to be reckoned with in clinical headache work and research?

The current criteria for cervicogenic headache (CEH) contain an anamnestic and a physical examination part. The latter consists of: 1) range of motion in the cervical spine (1+); 2) mechanical precipitation of head pain (uppermost score: 1.5+). These two factors are included in "Features indicative of cervical abnormality", outlined in the present context, with a view to possibly facilitating CEH diagnosis. These "features" have a wider scope, containing not only the two original factors (1 and 2), but also three additional factors--their relative contribution to the totality also given in parentheses: 3) facet joint tenderness (0.5+); 4) neck muscle tenderness (0.5+); and 5) skin-roll test (1.0+). The sum of the solitary features is, accordingly, 4.5+. An extra 0.5+ can be added if there is extreme positivity of one of the factors, i.e., a maximum of 5.0+. This coarse system concerning cervical function has also been tested out in 1834 parishioners in the V?g? study of headache epidemiology (irrespective of headache diagnoses). The mean number of features increased with increasing intensity of head pain (by a factor of almost 3). In headache-free individuals (n.=246), the mean was 0.42+, against a mean in the whole series of 0.79+. Reproducibility tests demonstrated relatively high consistency.     

Risk factors for drug addiction and its outcome. A follow-up study over 25 years

The aim of the study was to investigate factors related to initiation and abandonment of illegal drugs. A follow-up study on 53 drug addicts originally hospitalized because of parenterally acquired hepatitis was performed using questionnaires. The majority stated that curiosity and peer pressure were the main reasons for starting drug use. Family conflicts, school and mental problems were each reported by about 40% of the subjects. Thirty-nine patients (74%) had abandoned addictive drugs during the approximately 25 years that had elapsed since the hospital stay. All of these thought that own efforts had been most important in this achievement. Other important factors were help and support from family and friends, establishing a family or experiencing acute hepatitis or an overdose.     

Bright light treatment improves sleep in institutionalised elderly--an open trial

STUDY OBJECTIVES: This study evaluates the effects of bright light therapy among demented nursing home patients with sleep disturbances. DESIGN AND SETTING: 11 nursing home patients with actigraphically measured sleep efficiency below 85% took part in an open, non-randomised study where the subjects served as their own control. INTERVENTION: After two weeks of baseline measurements and two weeks of pretreatment measurements, patients received bright light exposure 2 h/day within the period 08:00-11:00 for two weeks. MEASUREMENTS AND RESULTS: Sleep-wake patterns during the 24-h day were evaluated by nursing staff ratings and wrist-worn motor activity devices (actigraphs). Sleep improved substantially with bright light exposure. Waking time within nocturnal sleep was reduced by nearly two h, and sleep efficiency improved from 73% to 86%. Corresponding improvements were found in nursing staff ratings. Effects were consistent across subjects. CONCLUSIONS: The findings add further evidence of the effectiveness of morning bright light exposure in the treatment of disturbed sleep among demented nursing home patients.     

Acute changes in neuromuscular excitability after exhaustive whole body vibration exercise as compared to exhaustion by squatting exercise

The effects of hard squatting exercise with (VbX+) and without (VbX-) vibration on neuromuscular function were tested in 19 healthy young volunteers. Before and after the exercise, three different tests were performed: maximum serial jumping for 30 s, electromyography during isometric knee extension at 70% of the maximum voluntary torque, and the quantitative analysis of the patellar tendon reflex. Between VbX+ and VbX- values, there was no difference found under baseline conditions. Time to exhaustion was significantly shorter in VbX+ than in VbX- (349 +/- 338 s versus 515 +/- 338 s), but blood lactate (5.49 +/- 2.73 mmol l-1 versus 5.00 +/- 2.26 mmol l-1) and subjectively perceived exertion (rate of perceived exertion values 18.1 +/- 1.2 versus 18.6 +/- 1.6) at the termination of exercise indicate comparable levels of fatigue. After the exercise, comparable effects were observed on jump height, ground contact time, and isometric torque. The vastus lateralis mean frequency during isometric torque, however, was higher after VbX+ than after VbX-. Likewise, the tendon reflex amplitude was significantly greater after VbX+ than after VbX- (4.34 +/- 3.63 Nm versus 1.68 +/- 1.32 Nm). It is followed that in exercise unto comparable degrees of exhaustion and muscular fatigue, superimposed 26 Hz vibration appears to elicit an alteration in neuromuscular recruitment patterns, which apparently enhance neuromuscular excitability. Possibly, this effect may be exploited for the design of future training regimes.     

Working-memory capacity and phonological processing in deafened adults and individuals with a severe hearing impairment

The purpose of the present article is to review a number of studies conducted in our own laboratory with respect to working memory capacity and phonological processing in deafened adults and individuals with a severe hearing impairment, and how these two cognitive components relate to speech processing. The results demonstrate that one specific component in the phonological processing system (i.e., the phonological representation system) is deteriorating, whereas other parts are preserved intact. The characteristic of the individual's phonological representation is further correlated with success in speech reading and speech understanding with some cochlear implant systems. Working memory capacity is a capacity that remains intact despite a long duration of deafness/severe hearing loss. The size of the working memory is related to skill in speech reading and level of speech understanding with cochlear implants and perceived effort in a noisy environment.