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E E Bakken

Publications and source records attributed to E E Bakken.

10 recordsLinked to original sources
PubMed2001

Chronomics.

Several international meetings have revealed an accumulating body of reference values for well-established about-daily and about-yearly rhythms of photic origin and evidence also for about-7-day, -27-day, -half-yearly, -10.5- and -21-yearly, and even -50-yearly rhythmicities in us as well as around us, as invisible non-photic heliogeophysical signatures possibly built into individuals and/or populations, complementing the biological year and day. In time series (biological or other) that are dense and sufficiently long, the characteristics of rhythms, chaos (deterministic and other) and trends can all be quantified as elements of structures called chronomes. Chronobiological methodology assesses uncertainties in comparisons of endpoints in all elements of chronomes, before and after: 1) changes in lifestyle, such as meal quality, quantity, timing and salting of the food; 2) preventive non-drug interventions to limit the risk of vascular disease; or 3) drug treatments for high-risk subjects as well as for those with actual vascular disease, all on a practicable, individualized and also a general population basis. A collateral hierarchy characterizes molecular to psychosocial aspects of living beings that are exposed to their socio-ecological environs and thus are synchronizable and/or otherwise manipulable by society, meals, lighting, heating, and non-photic, non-thermic environmental variations that become predictable to the extent that they appear to constitute cycles, yet adhere only to a statistical, rather than a deterministic causality. With this qualification, chronome mapping with outcomes could eventually serve an individualized optimization of lifestyle, for chronoprevention and chronotherapy as well as for inquiries into the evolution and future of life, a budding chronoastrobiology, in keeping with the original title of the conference.

Animals↗
PubMed2000

Feedsidewards: intermodulation (strictly) among time structures, chronomes, in and around us, and cosmo-vasculo-neuroimmunity. About ten-yearly changes: what Galileo missed and Schwabe found.

The spectrum of biological rhythms is extended far beyond circadians, circannuals, and ultradians, such as 1.5-hourly melatonin and 8-hourly endothelin-1 (ET-1) rhythms by statistics of natality, growth, morbidity, and mortality, some covering decades or centuries on millions of individuals. These reveal infradian cycles to be aligned with half-weekly rhythms in ET-1, weekly and half-yearly ones in melatonin, and even longer--about 50-, about 20-, and about 10-year cycles found in birth statistics. About daily, weekly, yearly, and ten-yearly patterns are also found in mortality from myocardial infarctions; the 10-yearly ones are also in heart rate and its variability; in steroid excretion, an aspect of resistance, for example, to bacteria; and in the genetic changes of the bacteria themselves. Automatic physiological measurements cover years and, in one case, cover a decade; the latter reveal an about 10-year (circadecennial) cycle. ECGs, covering months beat-to-beat, reveal circaseptans, gaining prominence in response to magnetic storms or after coronary artery bypass grafting. A spectrum including cycles from fractions of 1 Hz to circasemicentennians is just one element in biological time structures, chronomes. Chaos, trends, and any unresolved variability are the second to fourth elements of chronomes. Intermodulations, feedsidewards, account for rhythmically and thus predictably recurring quantitive differences and even for opposite treatment effects of the same total dose(s) of (1) immunomodulators inhibiting or stimulating DNA labeling of bone in health or speeding up versus slowing down a malignant growth and thus shortening or lengthening survival time, or (2) raising or lowering blood pressure or heart rate in the vascular aspect of the body's defense. Latitude-dependent competing photic and nonphotic solar effects upon the pineal are gauged by alternating yearly (by daylight) and half-yearly (by night) signatures of circulating melatonin at middle latitudes and by half-yearly signatures at noon near the pole. These many (including novel near 10-yearly) changes, for example, in 17-ketosteroid excretion, heart rate, heart rate variability, and myocardial infarction in us and those galactic, solar, and geophysical ones around us have their own special signatures and contribute to a cosmo-vasculo-immunity and, if that fails, to a cosmo(immuno?) pathology.

Animals↗
PubMed1992

Electrocardiogram of the humpback whale (Megaptera novaeangliae), with specific reference to atrioventricular transmission and ventricular excitation.

OBJECTIVES: The objective of the study was to record the electrocardiogram (ECG) of a large whale to obtain crucial data for comparative electrophysiologic analysis. BACKGROUND: The data were needed to establish the mismatch between heart size and PR interval and QRS duration in mammals. METHODS: In the waters off the coast of Newfoundland, in two humpback whales (Megaptera novaeangliae) with an estimated weight of 30,000 kg a 1-lead ECG was recorded, enabling reliable assessment of P waves and QRS complexes. RESULTS: It was found that both the PR interval (atrioventricular [AV] transmission time) and QRS duration (ventricular excitation) are extremely short for animals of this size. These findings are difficult, if not impossible, to explain on the basis of currently accepted electrophysiologic theories. However, the narrow QRS complex may be due to a very dense His-Purkinje network in the ventricular wall of whales. Alternative mechanisms that can explain the function of the mammalian AV node need to be considered and explored. CONCLUSIONS: The results of the study may be of value for the understanding of the ECG in humans.

Animals↗