Biomedical subjects

J Sitar

Publications and source records attributed to J Sitar.

At least 19 recordsLinked to original sources

PubMed1997

Can dobutamine echocardiography induce myocardial damage in patients with dysfunctional but viable myocardium supplied by a severely stenotic coronary artery?

In animal experiments, dobutamine infusion was found to impair the oxygen supply-demand balance in hypoperfused areas of hibernating myocardium which may induce myocardial damage. The aim of our study was to assess whether dobutamine echocardiography can induce myocardial damage detected by an increase in the cardiac troponin T level in blood. Twenty seven patients with coronary artery disease and severe stenosis of at least one major coronary artery (> or = 90% of luminal diameter narrowing) supplying dysfunctional myocardial segments underwent dobutamine echocardiography. Dobutamine was infused in 3 min dose increments of 5, 10, 20, 30, and 40 microg per kg body weight per minute with the addition of atropine up to 1 mg if ischemia or an 85% predicted maximal heart rate were not achieved. In 15 patients the protocol with prolonged application of 40 microg per kg per minute of dobutamine for 6 min and for the next 5 min with the addition of atropine was used. To exclude minor myocardial damage, an increase in the cardiac troponin T blood level was assessed qualitatively by the TROP T sensitive Rapid Test 20 h after dobutamine echocardiography. In 20 patients the dysfunctional segments were found to be viable with inducible ischemia exhibiting either continuous worsening in systolic thickening or "biphasic" response characterised by the improvement of their systolic thickening with a small dose and by a worsening of the thickening with a high dose of dobutamine. No patient exhibited positive TROP T sensitive Rapid Test result. In patients with coronary artery disease and severe stenosis of a major coronary artery supplying dysfunctional but viable myocardial segments, dobutamine echocardiography does not induce myocardial damage detectable by an increase in cardiac troponin T level.

Adult↗

PubMed1997

[Chronobiology of human aggression].

BACKGROUND: Violence is an urgent problem concerning society as a whole. If chronobiological changes of human aggressiveness existed, it would be possible to foresee them and when an increased incidence is expected it would be perhaps possible to use preventive measures. METHODS AND RESULTS: The author processed data on 2447 aggressive acts of violence and 1028 completed suicides (aggression against oneself) on the territory of the former South Moravian region according to a weekly, annual and lunar rhythm and in relation to sudden climatic changes. The most remarkable finding is that the impulsive bodily harm (usually without economic or sexual motivation) is very closely associated with sudden climatic changes, while burglary and rape do not depend on climatic changes and their frequency correlates with the semilunar rhythm (there are two peaks during lunation), similarly as the frequency of sudden cardiovascular deaths. In suicides the frequency changes, with certain exceptions, similarly as the incidence of impulsive intentional bodily assault. In general close to the phase of full moon aggressiveness is significantly reduced and not increased, as was and still is believed by mistake, based on few observations and impressions. CONCLUSIONS: The assessed periodicities differentiate types of aggressive behaviour, prove the possibility of prediction of an increase of the mean incidence and provide thus a basis for estimation of the time and type of increased aggressiveness. It is thus possible to introduce preventive measures.

Crime↗

PubMed1997

[Evaluation of diastolic filling of the left ventricle using Doppler echocardiography in patients with chronic ischemic heart disease and with normal left ventricular function].

Twenty-five patients with chronic ischaemic heart disease and intact left ventricular systolic function who had no other cardiovascular, systemic or metabolic diseases were examined by two-dimensional and Doppler echocardiography. At rest and during an isometric load Doppler parameters of left ventricular diastolic filling were obtained such as: peak transmitral flow velocity in early diastole - E, peak transmitral flow velocity in atrial contraction - A, their ratio E/A and deceleration time of early filling. Based on the coronarographic finding, the patients were divided in two ways: 1. group A - 15 patients with critical narrowing of some major coronary artery (stenosis > or = 90% of the luminal diameter) and group B - 10 patients without critical narrowing (stenosis > or = 50%, but less than 90% of the luminal diameter), 2 group C - 6 patients with triple vessel disease, group D - 8 patients with double vessel disease and group E - 11 patients with single vessel disease. None of the groups differed mutually in any of the investigated Doppler parameters of left ventricular filling at rest, nor after an isometric load. CONCLUSION. Diastolic Doppler parameters of left ventricular filling do not make it possible to detect patients with critical coronary narrowing and they do not help to estimate the number of coronary vessels with significant stenoses.

Blood Flow Velocity↗

PubMed1994

[The effect of the semilunar phase on an increase in traffic accidents].

BACKGROUND: As far as the author is aware no statistics of traffic accidents were so far concerned with the problem of a possible correlation of their frequency with the position of the moon, i.e. the lunar phase. Sudden cardiovascular deaths and some meteorological parameters (mean precipitation, atmospheric pressure and temperature) have this correlation and in most instances it is highly significant. METHODS AND RESULTS: The authors processed data pertaining to a total of 60,142 traffic accidents in the former South Moravian region in 1983, 1984, 1990, 1991 and 1992. The number of accidents on every particular day was classified according to the lunar phase. It was revealed that the frequency of accidents increases twice in the course of the lunar cycle (i.e. in the semilunar stages). The first increase is on the second and third day following new moon (t = 1.89 < 1.96 which is closely beneath the 5% level of statistical significance, p > 0.05). The second increase is more prolonged and more marked and starts already on the first day before full moon and persists after full moon with a maximum on the second day after full moon (t = 1.32 < 1.96, which again is beneath the 5% level of statistical significance, p > 0.05). The curve of the frequency of traffic accidents follows practically the same course as the curve of changes of atmospheric precipitation except for the day before full moon and the day after full moon. CONCLUSIONS: The revealed semilunar increase of traffic accidents is probably associated with the bi-phasic change of atmospheric precipitations with their increase closely after new moon and after full moon. However, one day before full moon the atmospheric precipitation is low and the increase in the accident rate on these days might be explained by the effect on the human factor, i.e. psychosomatic changes during the period near the full moon.

Accidents, Traffic↗

PubMed1994

[Extraterrestrial influences on health and disease].

As to extraterrestrial influences on man in health and disease so far only the effect of the sun and moon are known. This concerns the effect of solar radiation of different wavelengths and the effect of corpuscular solar radiation which has an impact on the condition of the terrestrial magnetic field and electric conditions in the atmosphere. Moreover there is also a question of important influences of gravitation (tides). Here the influence of the position of the moon in relation to the connecting line between sun and earth is involved. In the course of the synodic month (from new moon to the next new moon) a semilunar periodicity of different medical and geomagnetic indicators as well as meteorological ones plays a part. Based on his own research and that of others the author reaches the conclusion that extraterrestrial and terrestrial influences are interrelated and exert a mutual influence on each other and that it is not sensible to separate them strictly. Investigation of all the mentioned influences is important not only for biomedical prognosis but also for basic geophysical and meteorological research. Perspectively it would be useful to plan model experiments. The author feels it is his duty to refuse publication of different horoscopes in the mass media, whatever the intention. In the lay public this may lead to popularization of astrology which has nothing in common with serious research.

Death, Sudden, Cardiac↗

PubMed1993

[Short-term changes in cardiovascular mortality rates during a synodic month].

Statistically high significant periodicity (in the range of 2.3 to 4.2 days) in the cardiovascular mortality has been proved. This is connected with the alternation of lunar phases in the course of the synodic moon. The explanation as some endogene rhythms was excluded. To determine the origin of these short periodical changes will be a subject of further investigations.

Cardiovascular Diseases↗

PubMed1993

[The effect of weather and climate on the healthy and ill individual].

It has been known for thousands of years that changes of the weather and climate influence in a significant way man in health but in particular in disease. In the submitted paper the author describes different mechanisms of action of the mentioned factors, risk situations and also possible ways how to prevent adverse influences or to reduce at least their effect. In the conclusion the author mentions problems of biometeorological forecasts and the importance to take into account also extra-terrestrial influences. It is remarkable that less attention is paid to detailed, in particular experimental research, than corresponds to the serious character of disorders and their impact on the health status of the population.

Humans↗

PubMed1991

[Preventive care in patients with cardiac and vascular diseases during weather changes].

The author analyzes possible mechanisms of the development or deterioration of cardiovascular disorders in conjunction with changes of the weather. These mechanisms act not only at a cellular but also at a molecular and ionic level. Attention concentrates mainly on striking changes of blood clotting, aggregation of blood elements and viscosity of the blood. The author recommends some general ad special provisions to be taken before or during a change of weather by healthy hypersensitive subjects and by cardiovascular patients. The author emphasizes the necessity of close contact with the attending physician and the need to collect more findings, in particular experimental ones.

Blood Coagulation↗

PubMed1991

[Causes of exacerbation of diseases in the spring and fall].

The author draws attention to the fact that marked semi-annual changes of geomagnetic disturbances in spring and autumn could contribute also to the development or exacerbation of some pathological conditions. It is known that this semi-annual variation is displayed in particular by peptic ulceration of the stomach and duodenum, some forms of bronchial asthma, endogenous depressions, tetanic syndrome and liability to hyperglycaemia in obese diabetics. He refers to the parallel phenomenon in cardiovascular disorders. The author proved already previously that short-term (semilunar) geomagnetic changes correlate with adverse influences on the cardiovascular system, although the mechanism is probably different. He reflects also why in this context there are not two peaks of cardiovascular deaths in the course of the year. The concept of living environment is extended in recent decades also to cosmic space. Although some pathological conditions have a complicated genesis, in serious research it probably will not be possible to omit cosmic influences.

Cardiovascular Diseases↗

PubMed1991

[Correlation of certain parameters of solar winds and sudden cardiovascular deaths].

In day-to-day investigations the closest correlation with sudden cardiovascular mortality is displayed by the density of solar wind. An increased mortality is recorded after its brisk rise (in particular after potent proton phenomena) and paradoxically also in case of very low density value. Minor proton phenomena and eruptions with X-ray emission did not influence the mortality in the authors' group. This type of increased solar activity thus should not influence the prognosis of morbidity and mortality from cardiovascular diseases. When mean monthly density values of solar wind are correlated with mortality, the relationship is paradoxically indirect. The rate and temperature of the solar wind does not play any part due to its phase retardation after increased density. The correlation of mean annual values of all parameters of solar wind (i.e. density, velocity and temperature) and mortality is also indirect. There is no explanation so far for the increased mortality during low density levels during the interval between two rises in the course of day-to-day monitoring. For the short-term mortality prognosis thus potent proton phenomena can be used; the effect of very low values of solar wind density will have to be confirmed. The biogenic action of solar wind is obviously more complex than was formerly assumed.

Cardiovascular Diseases↗

PubMed1990

[The causality of lunar changes on cardiovascular mortality].

The author confirmed, based on different ways of processing of 1437 sudden cardiovascular deaths, that the frequency of these deaths changes in the course of the synodic moon with two maxima during the lunar quarters. Processing by the method of transfer of epochs made it possible to shift steadily the mortality curves according to the phase of solar activity. This made the author assume that the cause of the phenomenon of two-phasic change of mortality during lunation cannot be only gravitation (sudden tides) and that in addition the interfering influence of solar corpuscular radiation is involved. It is known that this radiation causes geomagnetic disorders. Consistent with the above view it was proved that in the course of lunation the greatest number of geomagnetic disorders occur at a time close to the lunar quarters. Then, as the author proved--aurora polaris is more frequent. The increased cardiovascular mortality is thus associated with an increased geomagnetic activity. The relationship is certainly not direct. The author indicates further trends of research to disclose the immediate causes which exert an unfavourable effect on our cardiovascular system.

Cardiovascular Diseases↗

PubMed1989

[Weekly biological rhythms in morbidity and mortality due to cardiovascular diseases].

Any assessment of the weekly rhythm of morbidity due to cardiovascular diseases should take into account the fact that as regards minor cases the rate of admission to the internal department outpatient unit is greatly distorted by the psychosocial factor, due to which the maximum number of admissions is on Mondays, the minimum on Saturdays; also Sundays are noted for a relatively low rate of admissions. It the subjective factor is eliminated by focussing attention solely on sudden cardiovascular deaths we can see the curve of frequency running in absolute reverse, i.e., that, on the contrary, Saturdays and Sundays at at-risk days. Mondays remain high-risk days, too, though not quite so prominently. The author discusses the cause of the phenomenon warning of the breaches of set biorhythms and of spells of stress not only at work but also during weekend "leisure" due to excessive physical as well as mental exertion.

Cardiovascular Diseases↗

PubMed1989

[The effect of solar activity on lunar changes in cardiovascular mortality].

After a 9-year follow-up of mortality due to cardiovascular emergencies (a total of 1,437 cases), the author found its frequency to be correlated with the moon phases. There are two maximum and minimum risk periods during lunation; the differences between them have a high statistical significance. The mortality study which registered the cases according to separate periods of maximum solar activity (spots, eruptions, etc.), medium and minimum activity recorded on three individual curves, showed that the maximum and minimum mortality curves were shifting in time phase so that during high solar activity, the minimum mortality was nearer to the new moon and full moon phases, while the maximum death rate approached the first and last lunar quarters; during the medium and low solar activities, the mortality maxima and minima were shifting counterclockwise the moon's orbit round the Earth, i. e. from the Earth's view with the Sun moving more and more to the west. The author offers some probable explanations for this phenomenon, which can help to make a more exact prognosis of critical days for patients with cardiovascular disorder. In addition, these findings can contribute to basic helio-geophysical research.

Cardiovascular Diseases↗

PubMed1988