Chronomes render predictable the otherwise-neglected human "physiological range": position paper of the BIOCOS project. BIOsphere and the COSmos.

On June 30, 1997, the Russian Academy of Medical Sciences convened a special session at its headquarters to discuss and, at the end of this meeting, to unanimously endorse a project on "The BIOsphere and the COSmos" (BIOCOS), a follow-up on various international resolutions reviewed elsewhere [1]. BIOCOS recommends the introduction of the science of the body's time structure, chronobiology [2], into basic science and health and environmental care via national physiological and physical monitoring and educational endeavors. More specifically, BIOCOS aims at the collection and archivization for basic and applied purposes at different latitudes and longitudes of physical and physiological time structures, or chronomes [1, 3]. The first step of BIOCOS is the systematic mapping of variation in human blood pressure and heart rate from womb to tomb and the opportunistic mapping of other variables in human and other life forms. On July 1, 1997, BIOCOS was introduced at the XXXIII International Congress of the International Union for Physiological Sciences in St. Petersburg, in the context of a symposium on "Adaptation to the Environment". Thereafter, BIOCOS was presented in a course on chronobiology in Mexico City, August 27-30, 1997, in lectures at Masaryk University, Brno, Czech Republic (September 1, 1997); at a meeting on "Chronobiology with roots in the cosmos", September 2-6, 1997, in Stara Lesna, Slovakia, under the auspices of the Slovak Medical Society; at Safarik University in Kosice (September 8) and the Institute of Clinical Endocrinology in Lubochna (September 9), both in Slovakia and at the International Conference on the Pineal Gland and Cancer (October 2-5, 1997) in Blaubeuren, Germany.

[Rhythmic fluctuations in hemoglobin oxygen affinity in premature infants over the space of 24 hours]. / Ritmicheskie kolebaniia srodstva gemoglobina k kislorodu u nedonoshennykh detei na protiazhenii sutok.

The noninvasive method for estimating the affinity of hemoglobin for oxygen (expressed as P50, oxygen tension at 50% hemoglobin saturation) allowed the authors to follow its time variations. Significant changes of P50 during 24 hours were demonstrated to occur in 16 preterm babies (the gestational age 30-37 weeks, body weight 1850-3000 g) with perinatal encephalopathy, along with fluctuations of tcpCO2, tcpO2, and SpO2. The changes of all these variables were rhythmic; the periods of best fitting cosine curves for P50 were 3-35 hours; double amplitudes, 2.92-17.42 mm Hg; the midline estimating statistics of rhythm, 18.2-33.7 mm Hg. There was a significant correlation between tcpO2 and P50 in 10 babies; in 7 cases, the acrophases of their rhythms coincided (the mean difference was 0.06 +/- 1.1 h). Thus, P50 in preterm babies is varying during a day, it varies periodically, in some cases the variations are due to the changes in pCO2.

[Development of arterial pressure rhythm and cardiac contraction rate and effects of beta-adrenomimetic agents]. / Stanovlenie ritmov arterial'nogo davleniia i chastoty serdechnykh sokrashchenii i vliianie beta-adrenomimetikov.

Blood pressure (BP) and heart rate (HR) rhythms were studied in premature infants (299 profiles ranged 24-106 h at 20--min intervals) and 11-13-year-old children (19 profiles for 48 h at 15-min intervals) to explore ultradian-to-circannual rhythm characteristics in BP and HR in preterm human infant and to elucidate the influence of antenatal betamimetic (BM) exposure on adolescent BP and HR rhythms. A circannual modulation of the 3-h amplitude (A) or MESOR of systolic BP (SBP) and diastolic BP (DBP) was seen mainly in prematures with a positive family history of high BP on the father's (f+) side or with both a patro linous and matro-linous history (f+m+), the circannual modulation of HR ultradian A was statistically significant only in "f- m-" infants. In urine collected at 3 h intervals for 24-h spans from 21 premature infants Na+,K+ and 11-oxycorticosteroids had a significant circadian rhythm. 9 adolescents (BM+), which were exposed in utero to different BM doses, had a significantly higher SBP and DBP MESOR and numerically higher circadian A as compared to 10 controls (BM-); correlation (P less than 0.05) between BM dose and HR circadian A was found. DBP led SBP in 8 or 10 "BM-" but in 4 of 9 "BM+" (acrophase difference 17 min and 3 min correspondingly).(ABSTRACT TRUNCATED AT 250 WORDS)

[Periodic fluctuations of the blood pressure and heart contraction rate in premature newborn infants]. / Periodicheskie kolebaniia arterial'nogo davleniia i chastoty serdechnykh sokrashchenii u nedonoshennykh novorozhdennykh.

To study the postnatal development of circadian rhythm of the blood pressure and the heart rate these parameters were monitored automatically during 24-72 hours at 5h intervals. Fifty infants were investigated at the age 1, 2, 3, and 4 weeks. The results were compared with the cosine curves of different periods (1-48 h) by the IBM PC XT. The fluctuations with all mentioned periods including circadian could be determined in each infant, dominating period being of any duration. In traditional approach the expressiveness of periodical fluctuations is evaluated by the amplitude of cosine curve. Application of the criterion has shown that only amplitude values exceeding 8 mm Hg should be taken into account. Hence, the analysis of BP and HR time series has demonstrated that about 45-50% of the infants have noncircadian rhythms, 20-20% have no significant periodical fluctuations and only 25-30% have circadian rhythm.

[Effect of antenatal hypoxia on the nature of the cry of newborn rats]. / Vliianie antenatal'noi gipoksii na kharakter krika novorozhdennykh krys.

Spectrography was used to examine spontaneous and pain (induced by pricking the foot with a needle) cries of newborn Wistar rats of the first three days of life. Three groups of animals were employed: non-operated control rats, those which suffered hypoxia on days 17-21 of gestation (clamping of the umbilical cord), and control rats born to operated females. The cries were recorded on Kometa or Vesna tape recorders and analyzed with the use of a Sona Graph, type 7029A. Antenatal hypoxia was found to produce an increase in the minimum and maximum pitches of fundamental frequency and to a decrease in the duration of the cry. It is likely that the changes in the cry are related to the impairment of the thalamic and hypothalamic nuclei and external respiration distress because of hypoxia.

[Rate of local cerebral blood flow in newborn rats in normo- and hypercapnia]. / Skorost' lokal'nogo mozgovogo krovotoka u novorozhdennykh krys v usloviiakh normo- i giperkapnii.

Local cerebral blood flow (1CBF) measured by hydrogen saturation technique, and cerebral blood volume (CBV) observed by photoplethysmographic method were investigated in unanesthetized newborn rats. 1CBF in newborn animals was found to be much lower than in the adult ones. In contrast to adult animals, CO2 inhalation in newborn rats failed to increase 1CBF. CBV also remained constant during the CO2 inhalation.

[Cerebrovascular response in newborns]. / Osobennosti reaktsii sosudov mozga novorozhdennykh

It was shown by the plethysmographic method that, in contrast to adult animals, in the newborn rats the blood vessels of the cerebral hemispheres and of diencephalon while displaying a distinct response to oxygen, failed to react to carbon dioxide, the latter being attributed to the low carbonic anhydrase activity in the tissues of these portions of the brain.