...Quarterly Journal of Experimental Physiology (1986) 71, 467-473 Printed in Great Britain FREE INTRACELLULAR MAGNESIUM CONCENTRATION IN FERRET VENTRICULAR MUSCLE MEASURED WITH ION SELECTIVE MICRO-ELECTRODES L. A. BLATTER AND JOHN A. S. McGUIGAN Department of Physiology, University of Berne, Buehlplatz 5, 3012 Berne, Switzerland (RECEIVED FOR PUBLICATION 2 AUGUST 1985) SUMMARY The free Mg concentration ([Mg]i) was measured in ferret ventricular muscle using singlebarrelled Mg-sensitive micro-electrodes. The electrodes were calibrated in solutions containing the [K]i and [Na]i measured in this tissue. In thirteen measurements from seven experiments conforming to strict criteria for calibration and penetration the estimated mean [Mg]i was 04 mmol/l. This is to be regarded as an upper limit since it was estimated by linear extrapolation of the calibration curve. INTRODUCTION Ionized Mg plays an essential role in the regulation of a large number of cellular functions. It is a co-factor in many enzymatic reactions, influences tension development in muscle and modulates amongst others the ionic transport systems in mitochondria (see reviews by Gunther, 1977; Shine, 1979; and Ackerman & Nicholls, 1983). Despite its importance in cellular mechanisms, estimations of the free Mg ([Mg]i) by various methods range from 0- 1 mmol/l to 6 mmol/l (reviews: Flatman, 1984; Gupta, Gupta & Moore, 1984) mainly because of the lack of a simple direct method for its measurement. Direct measurement of...
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...Problems of Stress and Burnout for Employees and Employers Introduction Work-related stress and burnout turn into a more widespread problem in the American workforce. Both employees and employers face problems when dealing with this issue. Our book defines burnout as a special type of job stress; a state of physical, emotional or mental exhaustion combined with doubts about your competence and the value of your work (Dressler, 2011). Stress is much more then just a specific situation though. Stress basically is a responsive reaction of an individual to a particular situation. This is why stress is usually difficult to cope with because every person reacts differently to a certain situation. Overwork, job insecurity, and other numerous factors have a negative effect on a person. Distress is produced, and an employee physiologically and psychologically deviates in her or his experiences in comparison to healthy functioning (Sandon, 2006). Stress and burnout are some unnecessary pressures at work can not only be detrimental to the well being of an employee but also affect the company in negative way. Causes of Stress and Burnout in the Workplace While mild stress can be beneficial to a person, providing stimulus and challenge. Stress becomes health threatening only when individuals feel unable to cope with demands expected from them. There is a clear difference between stress and burnout. Stress causes lots of anxiety and stirs up many emotions, while those suffering from...
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