Biomedical subjects

J Halberg

Publications and source records attributed to J Halberg.

22 records · Page 2Linked to original sources

PubMedDate not supplied

Variability of human blood pressure with reference mostly to the non-chronobiologic literature.

The voluminous literature on the variability encountered in 24-h recordings of human blood pressure in health is here presented by reference to selected clinical articles. Most references are cited by number for the sake of brevity, with a few cited by author when this appears to be of particular interest. Reports of work on laboratory animals are included when the findings are directly pertinent as background to studies on human beings. Results from semiautomatic and automatic direct and indirect measurements are briefly reviewed and aligned with results from work in which blood pressure was self-measured or measured conventionally by staff. The considerable and not generally recognized range of human blood pressure variability is thus extracted from the literature. An apparently limited extent of variation is shown to result mostly from the averaging of data from individuals constituting the groups investigated. Once variation is overwhelmingly documented and recognized as a fact, the different ways in which variations are presented and utilized by different author-investigators gain in importance. In a number of studies, methods of time series analysis are used. Thus, major attention can be paid to the extent to which predictable changes, so-called rhythms, characterize the data. Circadian rhythms are found to be quite prominent. By the assessment of these rhythms and about-yearly (circannual) ones, one quantifies health and individualized risk as well as disease. Otherwise 'unmanageable' variability, reviewed herein, can be resolved by relatively simple inferential statistical procedures as a set of new endpoints. A formidable foe thus becomes a powerful friend: the rhythm characteristics can be used in cardiovascular physiology and epidemiology, and preventive and curative medicine. Long-term blood pressure monitoring is no longer a mere research tool and a curiosity for the practitioner of medicine. Results from such monitoring should immediately be used in the clinic, in the school and at home. Automatic blood pressure monitoring, cost-effectively used in combination with self-measurement, as needed, may become a routine procedure if data collection can be wedded to appropriate analyses yielding new endpoints as sensitive gauges of health.

Adolescent↗

PubMedDate not supplied

Chronobiology of human blood pressure in the light of static (room-restricted) automatic monitoring.

Systematic 24-h automatic physiologic monitoring has obvious merits, even without rhythmometry. It can lead more readily to the recognition of odd-hour blood pressure elevation (e.g., of 'evening' or 'morning' hypertension). Such a condition can constitute an initial diagnosis or it may be found under treatment that may seem to be satisfactory if its effects are assessed only on the basis of a conventional check at a casual, possibly 'wrong' time. The mere inspection of a 24-h record, however, does not necessarily allow one to make objective quantitative global statements as to a change in pattern, e.g., after a given intervention. This paper illustrates how by rhythmometry, some of the uncertainties of a subjective interpretation of a record may be removed by practitioners of medicine, as well as basic scientists interested in mechanisms of blood pressure variability. This is possible since a large part of blood pressure variability can be accounted for by its circadian periodic behavior. We herein present a methodology for data collection and analysis that allows the objective quantification of blood pressure rhythm parameters in health and disease and the derivation of reference standards for such parameters. The chronobiologic approach thus makes it possible to define 'hypertension' objectively, and to distinguish between 'mesor-' and 'amplitude-hypertension', i.e., between an elevation in overall mean and one in the predictable extent of variability. Moreover, chronobiology has shown that mesor-hypertension may be preceded by an elevation in circadian amplitude only (amplitude-hypertension). Parameter tests readily allow the assessment, in relation to an objective reference standard, of these conditions, with a defined probability. Similarly, response to drug or non-drug therapy can be established and a given intervention optimized by timing treatment. Using chronobiologic tools in cardiovascular research provides new insights into possible mechanisms underlying mesor- and amplitude-hypertension. The teaching of the chronobiology of blood pressure and autorhythmometry in schools has been proven to be feasible and has been recommended as a step toward self-help for health care.

Adolescent↗

PubMedDate not supplied

Spectral differences between epitopes in the cronomes of salivary CA130 and CA125.

Ovarian tumor markers CA125 and CA130 are here investigated in the search for harbingers of an elevated cancer risk or pre-cancer. A circadian rhythm of large amplitude is demonstrated for salivary CA125 and CA130 of a clinically healthy 28-year-old woman (AP). The circadian rhythms of both markers found in AP have a pattern similar to that of a patient (EH) with a müllerian cancer involving the ovary, with high values in the early morning and low values in the afternoon. Whereas acrophases occur approximately at the same circadian stage in both AP and EH, the MESOR and circadian amplitude are higher in EH as compared to AP. The circadian rhythm of salivary CA130 of AP is similar to that of other clinically healthy women. CA130 concentrations are lower than CA125 concentrations in unstimulated saliva (before rinsing of the mouth) in this clinically healthy woman (AP), and in other women studied herein. This difference between CA130 and CA125 concentrations is observed irrespective of circadian stage and irrespective of the concentration range of CA125 at the outset. After rinsing of the mouth, a statistically significant decrease in both CA130 and CA125 concentration is observed in AP and in another healty woman (GC) who collected saliva both before and after rinsing of the mouth.

Adult↗

PubMedDate not supplied

Metachronanalysis of circannual and circasemiannual characteristics of human suprachiasmatic vasopressin-containing neurons.

We here test for and detect anticipated about-yearly (circannual) changes in the volume and number of vasopressin-containing neurons in the human suprachiasmatic nucleus. We then resolve inferential statistical parameters quantifying the extent and timing (the amplitude and acrophase) of the circannual rhythm previously missed by data inspection and classical biometry. We parametrize about-half-yearly changes previously validated by non-parametric statistical tests. New dynamic circannual and circasemiannual endpoints thus become available for basic investigation and the assessment of disease risk elevation and/or chronoprotopathology. It was earlier demonstrated that the circannual rhythms of prolactin and TSH are prominent classifiers of individuals at high versus low familial and other risk for developing breast or prostate cancer. Any neurocrine or neural mechanisms contributing to this classification are now amenable to study, on a population basis, with the dynamic hypothalamic rhythm characteristics yielded by this metachronanalysis.

Cell Count↗