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1.
Biomed Pharmacother ; 59 Suppl 1: S239-61, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275502

RESUMO

We analyzed cycles with periods, tau, in the range of 0.8-2.0 years, characterizing, mostly during 1999-2003, the incidence of sudden cardiac death (SCD), according to the International Classification of Diseases, 10th revision (ICD10), code I46.1. In the tau range examined, only yearly components could be documented in time series from North Carolina, USA; Tbilisi, Georgia; and Hong Kong, in the latter two locations based on relatively short time series. By contrast, in Minnesota, USA, we found only a component with a longer than (= trans) yearly (transyearly) tau of 1.39 years; the 95% confidence interval (CI) of the tau extended from 1.17 to 1.61 years, falling into the category of transyears (defined as a tau and a 95% CI between 1.0 and 2.0 years, with the limits of the 95% CI of the spectral component's tau overlapping neither of these lengths). During the same span from 1999 to 2003 in Arkansas, USA, a component of about 1-year in length was present, and in addition, one with a tau of 1.69 year with a CI extending from 1.29 to 2.07 years, a far-transyear candidate, far-transyears being defined as having a tau with a CI between 1.20 and 2.0 year, with the CI overlapping neither of these lengths. In the Czech Republic, there was also a calendar-yearly tau and one of 1.76 years. In the latter two geographic/geomagnetic areas, the about-yearly and the longer cycles' amplitudes were of similar prominence. The taus are only candidate transyears; the 95% CIs of their taus overlap the 2-year length. When a series on SCD from 1994 to 2003 from the Czech Republic was analyzed, the 95% CI of the transyear's tau no longer overlapped the 2-year length. Transyears were also found in the Czech Republic for myocardial infarctions (MI), meeting the original transyear definition in both a shorter and a longer series. Moreover, in the 1994-2003 series on MI from the Czech Republic, a near-transyear was also found, meeting the definition of a period with a 95% CI overlapping neither precisely 1.0 year nor 1.2 years, along with a far-transyear, defined as a tau between 1.2 and 2.0 years, again with the 95% CI covering neither of these lengths. Herein, we discuss near- and far-transyears more generally in the light of their background in physics and the concept of reciprocal cyclicities.


Assuntos
Fenômenos Cronobiológicos , Morte Súbita Cardíaca/epidemiologia , Infarto do Miocárdio/epidemiologia , Atividade Solar , República Tcheca/epidemiologia , Geografia , República da Geórgia/epidemiologia , Hong Kong/epidemiologia , Humanos , Estados Unidos/epidemiologia
2.
Biomed Pharmacother ; 59 Suppl 1: S24-30, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275503

RESUMO

A multi-center four-hourly sampling of many tissues for 7 days (00:00 on April 5-20:00 to April 11, 2004), on rats standardized for 1 month in two rooms on antiphasic lighting regimens happened to start on the day after the second extremum of a moderate double magnetic storm gauged by the planetary geomagnetic Kp index (which at each extremum reached 6.3 international [arbitrary] units) and by an equatorial index Dst falling to -112 and -81 nT, respectively, the latter on the first day of the sampling. Neuroendocrine chronomes (specifically circadian time structures) differed during magnetically affected and quiet days. The circadian melatonin rhythm had a lower MESOR and lower circadian amplitude and tended to advance in acrophase, while the MESOR and amplitude of the hypothalamic circadian melatonin rhythm were higher during the days with the storm. The circadian parameters of circulating corticosterone were more labile during the days including the storm than during the last three quiet days. Feedsidewards within the pineal-hypothalamic-adrenocortical network constitute a mechanism underlying physiological and probably also pathological associations of the brain and heart with magnetic storms. Investigators in many fields can gain from at least recording calendar dates in any publication so that freely available information on geomagnetic, solar and other physical environmental activity can be looked up. In planning studies and before starting, one may gain from consulting forecasts and the highly reliable nowcasts, respectively.


Assuntos
Fenômenos Cronobiológicos , Campos Eletromagnéticos , Sistemas Neurossecretores/fisiologia , Atividade Solar , Animais , Ritmo Circadiano , Retroalimentação , Hipotálamo/metabolismo , Iluminação , Melatonina/metabolismo , Glândula Pineal/metabolismo , Ratos , Ratos Wistar
3.
Chronobiol Int ; 3(3): 189-95, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3677202

RESUMO

Clinically healthy diurnally active young adult women were studied during the same season (March) at the Universities of Kyushu (Fukuoka City, Japan) and of Minnesota (Minneapolis, U.S.A.), under comparable conditions, except that the habitual diets were not changed. The subjects (20 Japanese and 16 Americans of mixed Caucasian background) were studied over a single 24-hr span. Urine was collected at 4-hr intervals. A circadian rhythm in total urinary norepinephrine excretion showed similar characteristics in Japanese and Americans. In epinephrine excretion, the Japanese women showed a statistically significantly higher amplitude with higher peak values, but no statistically significant difference in the rhythm-adjusted mean. This intergroup difference is strictly time dependent; it does not come to the fore in urine samples covering the nocturnal rest span of the subjects.


Assuntos
Ritmo Circadiano , Epinefrina/urina , Norepinefrina/urina , Adulto , Feminino , Humanos , Japão , Valores de Referência , Estados Unidos
4.
Biofizika ; 43(4): 666-9, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9783075

RESUMO

A human biologic week in the heart rate variations was compared with the variations of the sunspot area and geomagnetic activity over the solar cycle. The low ratio of amplitude of circaseptan rhythm to that of circadian rhythm in the heart rate of several clinically healthy men who did around-the-clock self-measurements in a number of years coincides with the period of anomalously low amplitude of circaseptan rhythm of the solar activity. Results herein suggest that physiologic circaseptan rhythms are built into the genome being adapted evolutionary to the original heliogeomagnetic environmental circaseptans.


Assuntos
Contração Miocárdica , Periodicidade , Atividade Solar , Adaptação Fisiológica/genética , Genoma , Humanos , Masculino
5.
Fiziol Cheloveka ; 30(2): 86-92, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15150979

RESUMO

AIMS: Velocity changes in the solar wind, recorded by satellite (IMP8 and Wind) are characterized by a solar cycle dependent approximately 1.3-year component. The presence of any approximately 1.3-year component in human blood pressure (BP) and heart rate (HR) and in mortality from myocardial infarction (MI) is tested and its relative prominence compared to the 1.0-year variation. MATERIALS AND METHODS: Around the clock manual or automatic BP and HR measurements from four subjects recorded over 5 to 35 years and a 29-year record of mortality from MI in Minnesota were analyzed by linear-nonlinear rhythmometry. Point and 95% confidence interval (CI) estimates were obtained for the approximately 1.3-year period and amplitude. The latter is compared with the 1.0-year amplitude for BP and HR records concurrent to the solar data provided by one of us (JDR). RESULTS: An approximately 1.3-year component is resolved nonlinearly for MI, with a period of 1.23 (95% CI: 1.21; 1.26) year. This component was invariably validated with statistical significance for BP and HR by linear rhythmometry. Nonlinearly, the 95% CI for the 1.3-year amplitude did not overlap zero in 11 of the 12 BP and HR series. Given the usually strong synchronizing role of light and temperature, it is surprising that 5 of the 12 cardiovascular series had a numerically larger amplitude of the 1.3-year versus the precise 1.0-year component. The beating of the approximately 1.3-year and 1.0-year components was shown by gliding spectra on actual and simulated data. DISCUSSION AND CONCLUSION: The shortest 5-year record (1998-2003) revealed an approximately 1.3-year component closer to the solar wind speed period characterizing the entire available record (1994-2003) than that for the concurrent 5-year span. Physiological variables may resonate with non-photic environmental cycles that may have entered the genetic code during evolution.


Assuntos
Pressão Sanguínea/fisiologia , Fenômenos Cronobiológicos , Frequência Cardíaca/fisiologia , Infarto do Miocárdio/mortalidade , Atividade Solar , Adulto , Idoso , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Minnesota/epidemiologia , Dinâmica não Linear , Periodicidade , Vento
6.
Biologia (Bratisl) ; 51(6): 749-56, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11541945

RESUMO

In several human adults, certain solar activity rhythms may influence an about 7-day rhythm in heart rate. When no about-weekly feature was found in the rate of change in sunspot area, a measure of solar activity, the double amplitude of a circadian heart rate rhythm, approximated by the fit of a 7-day cosine curve, was lower, as was heart rate corresponds to about-weekly features in solar activity and/or relates to a sunspot cycle.


Assuntos
Fenômenos Cronobiológicos , Ritmo Circadiano , Frequência Cardíaca/fisiologia , Atividade Solar , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Chronobiologia ; 20(1-2): 116-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8354099
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