Anders Kallner

Neuroendocrine and immunologic effects of unemployment and job insecurity.

We prospectively followed a cohort of 354 blue-collar men and women, some of whom lost their jobs. Results show marked effects during the anticipatory and early unemployment phase on mental well-being, serum cortisol, prolactin, total cholesterol, HDL cholesterol, and phytohemagglutinin reactivity of lymphocytes. Most of these changes appear to be of short-term duration. However, changes in cardiovascular risk factors are observed at least 2 years following the loss of ones job. Coping style appears to be a major determinant whether or not and how people will react to unemployment.

Stress and psoriasis: psychoendocrine and metabolic reactions in psoriatic patients during standardized stressor exposure.

&NA; Psychoendocrine and metabolic reactions during standardized stressor exposure (color‐word conflict test and forced mental arithmetics) were studied in ten psoriatic and ten matched healthy subjects. During resting conditions, the groups were similar with regard to psychologic and biochemical variables, except for plasma glucose, which was slightly elevated in the psoriatic group. During stressor exposure, the psoriatic group reported significantly higher strain levels. Blood pressure, pulse rate, plasma glucose, and urinary adrenaline excretion increased in both groups during exposure, with more pronounced increases of the latter two in the psoriatic group. Serum cortisol, prolactin, progesterone and urinary cortisol decreased in both groups during stressor exposure. The decrease in serum cortisol was more pronounced in the psoriatic group. Thus, no psychoendocrine differences were found between the healthy and psoriatic subjects during resting conditions. In contrast, during a standardized stressor exposure, psoriatic subjects reported higher levels of strain, which was accompanied by higher levels of urinary adrenaline and lower levels of plasma cortisol. These results fit the hypothesis that psoriatic patients perceive certain challenging situations as more stressful than do nonpsoriatic controls, and react accordingly in their differential psychoendocrine reaction pattern. Possible pathophysiologic implications of the different pituitary‐adrenocortical and sympatho‐adrenomedullary reactions in psoriatics submitted to stressor exposure are discussed.

Determination of phosphate in serum and urine by a single step malachite-green method

The highly sensitive malachite-green method for the determination of phosphate requires a protective colloid in order to avoid precipitation of the formed dye salt. A polyvinylalcohol proved to be suitable and permit the determination of phosphate in urine and in serum without prior precipitation of the proteins. The present method is suitable for a one-step procedure which allows the analysis of several hundred samples per man-hour and is applicable to microquantities of serum or urine.

An experimental study of social isolation of elderly people: psychoendocrine and metabolic effects.

&NA; Psychoendocrine and metabolic effects of social isolation and understimulation in real life were examined in a controlled study of 60 elderly people representative of their age group. Together with the staff and the elderly, a social activation program was formed at a senior citizen apartment building. Half of the elderly were part of this activation program (experimental group). The other half constituted the control group. Blood sampling and psychosocial testing were performed immediately before and after 3 and 6 months of social activation. Social activation increased threefold in the experimental group. Height decreased in the control group compared to the experimental subjects. Plasma levels of testosterone, dehydroepiandrosterone, and estradiol increased significantly in the experimental group over the 6‐month period compared to the control group. The most pronounced increase took place during the initial 3 months. Hemoglobin A1c decreased significantly in the experimental group over the 6‐month period compared to the control group. In this preliminary study it is concluded that social isolation and understimulation may be associated with a wide range of psychophysiologic effects in elderly people.

Myocardial Injury After Electrical Therapy for Cardiac Arrhythmias Assessed by Troponin-T Release

Episodes of ventricular fibrillation with subsequent intracardiac, and to a lesser extent, external defibrillation give rise to a statistically significant increase in S-troponin T, S-CK-MB(mass) and S-myoglobin indicative of a minor myocardial injury or dysfunction. In contrast, no such signs were observed after external direct-current conversion of atrial fibrillation using high energies, or after pace-terminated ventricular tachycardia.

A psychosocial and biomedical comparison between men in six contrasting service occupations

Abstract A study of psychosocial job factors and physiological states was conducted using 150 men, aged between 25 and 60, working in six widely different occupations—freight handlers, aircraft mechanics, air traffic controllers, physicians, waiters and symphony musicians. The aim of the study was to characterize any differences in physiological parameters in relation to differences in psychosocial job characteristics. Analyses of variance were used to test differences between groups. The results indicated that waiters, the group reporting the most unfavourable working conditions, tended to have many cardiovascular risk factors. Physicians, who had relatively few cardiovascular risk factors, reported high decision latitude and many emotional reactions in their daily life and had relatively high cortisol and low prolactin levels in plasma.

A 50-Hz electromagnetic field impairs sleep.

In view of reports of health problems induced by low frequency (50–60Hz) electromagnetic fields (EMF), we carried out a study in 18 healthy subjects, comparing sleep with and without exposure to a 50Hz/1μTesla electrical field. We found that the EMF condition was associated with reduced: total sleep time (TST), sleep efficiency, stages 3+4 slow wave sleep (SWS), and slow wave activity (SWA). Circulating melatonin, growth hormone, prolactin, testosterone or cortisol were not affected. The results suggest that commonly occurring low frequency electromagnetic fields may interfere with sleep.

Myocardial release of troponin T after coronary bypass surgery

The temporal changes in cardiac S-troponin T, S-creatine kinase-MB(S-CK-MB)mass and S-myoglobin were studied for 5 days after coronary bypass grafting in 70 patients. Perioperative infarction occurred in ten patients (2 Q wave, 8 non-Q wave). All three markers showed significant increase even in patients without signs of perioperative infarction. Within 8-12 hours their levels rose significantly (p < 0.001) more in the infarction than in the non-infarction cases. Troponin T and CK-MBmass both showed early (< 8-12 h) peaks in patients with perioperative infarction. CK-MBmass returned to near normal levels within 48-72 hours, whereas troponin T remained markedly increased throughout the observation. Myoglobin concentrations varied widely among the infarction cases. In the non-infarction group, troponin T and CK-MBmass (but not myoglobin) were related to the aortic cross-clamp time. Troponin T (but not CK-MBmass) remained elevated throughout the study period in patients with longer cross-clamp times. These findings may indicate continuous release from damaged myocardium in cases of perioperative infarction. Troponin T and CK-MBmass can serve as markers of perioperative infarction and troponin T may also be useful as a marker in studies on myocardial protection.

Renal function in community-dwelling frail elderly. Comparison between measured and predicted glomerular filtration rate in the elderly and proposal for a new cystatin C-based prediction equation

Background and aims: There is a great need to evaluate renal function regularly in elderly people. This study aimed at analyzing renal function in stable, community-dwelling elderly people of 75 years and over, to compare measured and predicted glomerular filtration rates (GFR) and to develop an accurate prediction equation for this age group. Methods: Forty-five ambulatory elderly people in stable health in ordinary living were randomly selected into four age-classes, aged 75–95. Demographic data, personal activities of daily living, continuous drug prescriptions, body composition, blood pressure and blood chemistry were analysed. GFR was measured as Iohexol clearance based on three time-points 3, 4 and 7 hours after lohexol injection. Results: Mean GFR was well preserved in all four age-classes. The GFR range was 18–83 mL/min and declined with age. The Cockcroft-Gault prediction equation systematically underestimated measured GFR. A new ‘GFRA’ prediction equation is presented, based on the inverse of serum cystatin C and independent of gender, body surface area, body weight, lean body mass or serum creatinine. The proposed equation underestimated measured GFR with a mean of only 0.1 mL/min, had better precision compared with the Cockcroft-Gault equation, and was evaluated by the method of cross-validation. Conclusions: GFR exhibits extensive heterogeneity in frail, community-dwelling elderly people. The proposed GFRA was clearly more precise than the Cockcroft-Gault prediction equation in the study group. However, it needs to be validated in a larger population of elderly subjects, including more individuals in stable health with substantially reduced renal function in whom GFR is measured by a reference method with adequate sampling time.

Release of markers of myocardial and endothelial injury following cold cardioplegic arrest in pigs

Cold cardioplegic arrest causes reperfusion injury to both endothelium and myocardium. We investigated release of troponin-T (TnT), tissue plasminogen activator activity (t-PA) and histamine (HA) from the heart before and after 2h of cold crystalloid cardioplegia in eight Swedish landrace pigs. Coronary sinus blood flow was measured in an external shunt between the coronary sinus and the right atrium. TnT, t-PA and HA were measured concomitantly in arterial and coronary sinus plasma, and the cardiac release was calculated. Cardiac release of TnT increased from 18 (15-25) micrograms/min (median (central 90% percentile)) before cold cardioplegia to maximum 281 (132-510) micrograms/min 30 min after aortic declamping (p < 0.02 vs initial value). t-PA rose from -4 (-52-34) to maximum 249 (75-691) IU/min 2 min after declamping (p < 0.01) and thereafter returned to baseline levels. The net cardiac release of HA was 72 (-80-1321) nmol/min before cardioplegia, rising to 234 (-188-524) after 2 min of reperfusion (p < 0.02) and returning to baseline after 30 minutes. We conclude that the porcine heart releases t-PA, Tn-T and HA during postcardioplegic reperfusion. The differing kinetics of their release may indicate different affection of the myocardium and the endothelium. Tn-T, t-PA and HA are potential markers of myocardial and endothelial injury in the porcine heart.