Visualization of painful experiences believed to trigger the activation of affective and emotional brain regions in subjects with low back pain

In the management of clinical low back pain (LBP), actual damage to lower back areas such as muscles, intervertebral discs etc. are normally targeted for therapy. However, LBP may involve not only sensory pain, but also underlying affective pain which may also play an important role overall in painful events. Therefore we hypothesized that visualization of a painful event may trigger painful memories, thus provoking the affective dimension of pain. The present study investigated neural correlates of affect processing in subjects with LBP (n = 11) and subjects without LBP (n = 11) through the use of virtual LBP stimuli. Whole brain functional magnetic resonance imaging (MRI) was performed for all subjects while they were shown a picture of a man carrying luggage in a half-crouching position. All subjects with LBP reported experiencing discomfort and 7 LBP subjects reported experiencing pain. In contrast to subjects without LBP, subjects with LBP displayed activation of the cortical area related to pain and emotions: the insula, supplementary motor area, premotor area, thalamus, pulvinar, posterior cingulate cortex, hippocampus, fusiform, gyrus, and cerebellum. These results suggest that the virtual LBP stimuli caused memory retrieval of unpleasant experiences and therefore may be associated with prolonged chronic LBP conditions.     

Parameters of cortical interactions in subjects with high and low levels of verbal creativity

Parameters of cortical interactions depending on the level of creative achievements were studied in 40 right-handed subjects (22 men and 18 women). EEG was recorded at rest and during performance of a verbal creativity task (the Cognitive Synthesis test). The subjects were divided (by the median split) into groups with high and low originality scores (OSs). EEG coherence was computed within a range of frequencies from 4 to 30 Hz. The total values of coherence were determined separately for intra- and interhemispheric coherent connections using each of 16 electrode sites. Unlike subjects with a low OS, those with a high OS values were characterized by a decrease in the interhemispheric coherence of the θ_1,2-rhythm bioelectric potentials, which was especially pronounced in frontal cortical regions, and by an increased β₁-rhythm interhemispheric coherence in the occipital and temporal-parietal brain regions. The results are discussed in the context of right- and left-hemisphere contributions into the top-down and bottom-up regulation mechanisms during creative thinking.     

Cardiovascular reactivity to mental stress: relationship with menstrual cycle and gender

The purpose of the present study was to determine the fluctuation in cardiovascular reactivity to mental stress during the menstrual cycle by comparing heart rate variability (HRV), and other physiological and psychological data in females with those in males. Cardiovascular reactivity to two mental tasks was measured in 14 females during the follicular and luteal phase of menstruation over two menstrual cycles. The same tasks were subsequently given to a matched pair of males (N=14), at the same intervals as their corresponding females. Heart rate, blood pressure and HRV were used as indices of cardiovascular reactivity. Subjective mental workload was measured at the end of each task. Power spectral analysis of HRV showed that the high frequency (HF) component in HRV decreased more during the luteal phase than the follicular phase. The low frequency (LF) component in HRV and the LF/HF ratio in the luteal phase were significantly higher than that in the follicular phase. The LF component and the LF/HF ratio were significantly lower in females than in males; conversely, the HF component was significantly higher in females than in males. Neither significant effects of menstrual cycle, gender and mental stress nor any significant interactions were found for mental workload. These findings indicate that sympathetic nervous activity in the luteal phase is significantly greater than in the follicular phase whereas parasympathetic nervous activity is predominant in the follicular phase. The results also suggest that predominance of sympathetic nervous activity in males compared with a dominant parasympathetic nervous activity in females.     

Composition and lipid spatial distribution of HDL particles in subjects with low and high HDL-cholesterol

A low level of high density lipoprotein cholesterol (HDL-C) is a powerful risk factor for cardiovascular disease. However, despite the reported key role of apolipo-proteins, specifically, apoA-I, in HDL metabolism, lipid molecular composition of HDL particles in subjects with high and low HDL-C levels is currently unknown. Here lipidomics was used to study HDL derived from well-characterized high and low HDL-C subjects. Low HDL-C subjects had elevated triacylglycerols and diminished lysophosphatidylcholines and sphingomyelins. Using information about the lipid composition of HDL particles in these two groups, we reconstituted HDL particles in silico by performing large-scale molecular dynamics simulations. In addition to confirming the measured change in particle size, we found that the changes in lipid composition also induced specific spatial distributions of lipids within the HDL particles, including a higher amount of triacylglycerols at the surface of HDL particles in low HDL-C subjects. Our findings have important implications for understanding HDL metabolism and function. For the first time we demonstrate the power of combining molecular profiling of lipoproteins with dynamic modeling of lipoprotein structure.     

Selection of mice for high level of extrapolation capacity with cobcommitant low anxiety level

The behavior scores were assessed in mice selected simultaneously for high percentage of correct extrapolation task solutions and for low anxiety during test performance. Extrapolation test requires that the hungry animal searches for the food bait which disappeared from the view moving in the direction of food bait movement. In the 4th selection generation no significant changes occurred in the percentage of correct task solutions neither in comparison to control unselected population, nor against 50% chance level. Although the proportion of mice in selected strain which performed with 80-100% of correct solutions increased and in F4 was higher in comparison to controls (approaching significance). The proportion of "0" solution (when mouse made no choice) and of "refusals" of performance (anxiety indices in this test) were lower in selected line and the proportion of refusals in F4 was significantly lower than in controls. Elevated plus maze, closed plus maze and inescapable slippery funnel tests demonstrated significantly lower anxiety in mice of selected strain. These data demonstrate much more complex genetic basis for the capacity for extrapolation (lack of response to selection) in comparison with that of anxiety traits in mice (changes in the response to selection).     

Habituation of evoked potentials in subjects with high, medium and low levels of anxiety

The habituation of the peak-to-peak amplitudes of N1P2 and P2N2 complexes of the evoked potentials as responses to series of the increasing number of visual and acoustic stimuli was investigated in 55 male and female volunteers aged 20-30. The size and speed of the habituation process were approximated by hyperbola. The shape and coefficients of the hyperbola were correlated with high, medium and low levels of the anxiety and probably reflected the balance between synchronization and desynchronization processes in the cortex.     

Reduction in blood pressure with a low sodium,high potassium,high magnesium salt in older subjects with mild to moderate hypertension.

OBJECTIVE--To examine the effect of a reduced sodium and increased potassium and magnesium intake on blood pressure. DESIGN--Randomised double blind placebo controlled trial. SETTING--General population of a suburb of Rotterdam. SUBJECTS--100 men and women between 55 and 75 years of age with untreated mild to moderate hypertension. INTERVENTIONS--During 24 weeks the intervention group received a mineral salt (sodium: potassium: magnesium 8:6:1) and foods prepared with the mineral salt. Controls received common salt and foods. MAIN OUTCOME MEASURE--Change in blood pressure. RESULTS--Complete follow up was achieved for 97 of the 100 randomised subjects. Systolic blood pressure (mean of measurements at weeks 8, 16, and 24) fell by 7.6 mm Hg (95% confidence interval 4.0 to 11.2) and diastolic blood pressure by 3.3 mm Hg (0.8 to 5.8) in the mineral salt group compared with the controls, with a 28% decrease in urinary sodium excretion and a 22% increase in urinary potassium excretion. Twenty five weeks after the study the difference in blood pressure between the groups was no longer detectable. CONCLUSION--Replacing common sodium salt by a low sodium, high potassium, high magnesium mineral salt could offer a valuable non-pharmacological approach to lowering blood pressure in older people with mild to moderate hypertension.     

Features of endocrine and cardiovascular response to emotional stress in subjects with different types of temperament

Functional features of endocrine and cardiovascular response to examination stress were investigated in 105 students of the Medical Academy who were divided into three groups according to their temperament types. Subjects with the “Apollon” type of temperament were found to have an adequate response to emotional stress. Subjects with the “Epimetei” type of temperament were characterized by the inert response of the regulatory and effector body systems, which was a prerequisite for the development of endocrine and cardiovascular disturbances. The prevalence of parasympathetic activity in the dynamics of emotional stress in subjects of the “Dionisii” type of temperament is indicative of their resistance to the harmful effect of stress. The preliminary psychological evaluation of the type of temperament makes possible the prognosis of adaptive reactions to stress or dysadaptation.     

Changes in the brain's electrical activity during habituation to verbal stimulus in subjects with high and low levels of personal anxiety

Brain electrical activity during habituation to repeated verbal stimulus was recorded in subjects with high and low levels of personal anxiety. During habituation of subjects with low anxiety, the spectral power of EEG alpha and theta bands increased in the frontal cortical areas. Such a reaction was not observed in subjects with high anxiety level. Moreover, during habituation traces, the latency of P300 of the auditory evoked potential increased. This parameter did not depend on anxiety level. The amplitude of P300 in the right temporal region was shown to be related to anxiety level: it increased after habituation in subjects with low anxiety and did not change in subjects with high anxiety.     

Molybdenum nutrition of rice under low and high nitrogen level

Summary Rice (Oryza sativa L.) cv. IR8 was grown in sand culture with nutrient solutions of normal (40 ppm) nitrogen (N), and 3 times the normal nitrogen (3N) applied in the form of ammonium nitrate in combination with molybdenum as foliar spray at the rates of 0, 15. 30, and 45g per plant. In both the nitrogen concentration the foliar application of molybdenum increased the mean crop growth rates. Molybdenum application also increased nitrate reductase activity leading to higher concentration of reduced nitrogen in the tissue and thereby creating a concentration gradient for the uptake and assimilation of applied nitrogen. re]19760505     

Induction of emotional states during oral reading of texts with different emotional valence and EEG power dynamics in frequency bands beta2 and gamma

EEG power in frequency bands beta2 (18.5-29.5 Hz) and low gamma (30-40 Hz) was compared for situations while reading aloud with the technique "self-regulative utterance" texts as follow: a text with neutral emotional-semantic dominant; literary texts with either a positive or a negative emotional-semantic dominant; personal texts--recollections with similar dominants. Two groups of healthy subjects participated--a group of actor students (N=22) and a group of non-actor students (N=23). EEG power values in the states of emotiogenic texts reading are reproducibly differed with statistical significance from those in the state of reading ofa non-emotiogenic text. States of reading emotionally-positive texts are characterized by increases of EEG power in these bands, while those for emotionally negative texts--by decreases if compared with the state of emotionally neutral reading.     

Cardiovascular risk factors in subjects with Helicobacter pylori infection

Background. It has been proposed that Helicobacter pylori infection is related to cardiovascular disease, although this has not been fully investigated. The aim of this study was to investigate whether H. pylori in‐fection is associated with cardiovascular risk factors. Subjects and Methods. One thousand six hundred and fifty people undergoing annual medical checks at Shimane Institute of Health Science between September 1998 and August 1999 were enrolled. Gender, age, body mass index, habitual smoking and drinking, systolic and diastolic blood pressure, serum level of total cholesterol, triglyceride, high‐density lipoprotein cholesterol (HDLC), blood glucose, leukocyte count and hemoglobin were compared between H. pylori seropositive and seronegative cases. Results. In H. pylori seropositive individuals, HDLC was significantly lower than that in seronegative individuals. After adjustment for possible confounding factors (gender, age, BMI, smoking and drinking habits), mean HDLC in H. pylori‐seropositive and seronegative individuals were 56.1 and 58.2 mg/dl, respectively (p < .005). The percentage of the elderly (over 50 years old) individuals with HDLC < 35 mg/dl in H. pylori seropositive and seronegative groups were 7.4% and 4.7%, respectively (p < .001). In addition, the lower HDLC level was accompanied by an increased leukocyte count. Conclusion. Long‐term infection with H. pylori may have an important role in decreasing the serum HDLC concentration.