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Biomedical subjects

I S Breslav

Publications and source records attributed to I S Breslav.

At least 19 recordsLinked to original sources
PubMed2002

[Human respiratory sensory system, its physiological role].

Modern data on genesis and functional role of sensations associated with respiration, were analysed. Regularities of human perception of the respiratory cycle's parameters have been cited. Respiratory discomfort occurring in an increased loading of the respiratory system, as well as an imperative respiration stimulus developing in a prolonged apnoe or obvious hypoventilation, are regarded as defensive responses to a threat to normal ventilation of the lungs. The central link in mechanisms of the respiratory sensory system seems to involve pulses from receptors of the respiratory muscles.

Dyspnea↗
PubMed1990

[Initial expiratory activity as one of the criteria of the respiratory center function].

In 13 healthy men at rest and dosed muscular loads the authors studied maximal rates of the mouth pressure at the onset of inhalation and expiration (dP/dtI, dP/dtE) as well as the respiratory pattern. The parameter dP/dtE positively correlated with that of dP/dtI which reflects, as is known, an inspiratory activity of the respiratory center. The authors think that dP/dtE parameter can be used for noninvasive determination of expiratory activity.

Adult↗
PubMed1989

Ventilatory response kinetics and breathing pattern during exercise at different chemoreceptive drives.

For studying the effects of different chemoreceptive drives on the ventilatory responses to muscular work, experiments were carried out with 16 healthy men. They accomplished a 5-min exercise while breathing with different gas mixtures or after hyperventilation. As was shown, the rapid component of the exercise hyperpnea increased with intensifying the hypercapnic and/or hypoxic stimuli and was reduced or abolished with attenuation of these stimuli. At this, hypoxic drive exerted primary influence on the response kinetics. In the steady-state exercise effects of the chemoreceptive stimuli were modulated by biomechanical factors, which leads to a energetically optimum breathing pattern being formed.

Administration, Inhalation↗
PubMed1989

[The role of sensory components in reactions of the human respiratory system to increasing loads].

In 13 healthy male subjects performing an increasing work on veloergometer in conditions of resistive respiratory loads, the moments of sensation of respiratory difficulties and refusal from the work, were recorded. The analysis of the respiratory system functions revealed that the respiratory discomfort occurred with increasing of the alveolar PCO2 up to a certain value and that the refusal occurred on a certain level of inspiratory activity. The subjects believed that the moment of refusal coincided with the complete exhaustion of the respiratory system reserves. Their lung ventilation, however, as well as inspiratory effort were far from reaching the maximal values obtained in special tests. Apparently, the sensory components of responses to the combination of muscular work with an increased resistance against breathing are of a defensive character and directed to the prevention of the exhaustion of the respiratory system functional reserves.

Adult↗
PubMed1987

[Regulation of human respiration during a combination of resistive loading and muscular activity].

In 9 healthy subjects, effects of additional non-elastic resistance (the resistive load) on parameters of the respiration control were shown to be slight in resting whereas in muscular activity they involved a rearrangement of the respiration pattern and a considerable increase of inspiratory and expiratory activities. As opposed to these adaptive responses, however, the resistive load, the inspiratory-expiratory one in particular, reduced the increment of lung ventilation associated with the load, and led to a hypercapnia. Physiological mechanisms of these shifts are discussed.

Adult↗
PubMed1987

[Functional and diagnostic significance of a study of respiratory regulation in patients with chronic nonspecific lung diseases].

Respiratory regulation at rest and under the influence of increasing hypercapnia was investigated in patients with chronic nonspecific pulmonary diseases (CNPD) with restrictive and obstructive types of lung ventilation capacity disorder. An increase in the inspiratory activity of the central mechanisms of respiratory regulation was revealed even at the early stages of disease. The determination of this type of activity in comparison with respiratory pattern parameters could be of diagnostic value. CNPD patients with congenital immunopathies (Kartagener-Sievert syndrome, CNPD with alpha 1 antitrypsin deficiency) demonstrated concomitant respiratory regulation disorders in the form of low inspiratory activity in response to hypercapnia suggesting a complicated course of disease in these patients.

Adolescent↗
PubMed1985

[Effect of artificial anemia on the regulation of breathing in the rat before and after denervation of the sinocarotid reflexogenic zones].

Parameters of lung ventilation, oxygen consumption and the gas composition of the blood were studied in inhalation of air and mixtures with altered oxygen or carbon dioxide content against the background of 50% isovolumic hemodilution in animals with intact and denervated sino-carotid receptor areas. The arterial (sino-carotid) chemoreceptors are shown to play an important role in development of compensatory responses to limitation of oxygen transport induced by a drop of the blood oxygen capacity. Consequently, stimulation of these receptors is associated with disturbances in oxygen transport not only in cases of arterial PO2 drop but in conditions of reduction of the blood oxygen capacity due to anemia, as well.

Anemia↗
PubMed1983

[Human breathing patterns in hypercapnia and hypoxia].

In 3 young males with different types of breathing pattern, the responses of lung ventilation to hypercapnia and hypoxia were studied. Both kinds of the chemoreceptor activation of respiration increased the depth as well as the frequency of breathing. The subject with tachypnoic pattern of respiration responded to the hypercapnic and hypoxic stimuli mainly with an increase in the tidal volume whereas the bradypnoic subject almost exclusively responded with a faster breathing. The reasons for the above peculiarities are discussed.

Adult↗
PubMed1983

[Breathing pattern in the waking dog].

The parameters of lung ventilation: the tidal volume, the duration of inspiration and expiration as well as their derivatives, were recorded repeatedly in alert dogs. An obvious variability of patterns of respiration at a relatively stable level of ventilation was revealed. A positive correlation was found between the tidal volume and the cycle duration, particularly the inspiratory phase of the latter, which seems to maintain the isoventilatory character of the observer pericdic array not of the pattern.

Animals↗
PubMed1981

[Importance of chemoreceptor stimuli to the speed of switching the respiratory response to exertion on and off].

The magnitude of the exercise respiratory response and its switch on and switch off rates were studied in 12 normal men breathing different gas mixtures. It was shown that hypercapnic stimulus reinforced and accelerated the respiratory response to exercise. Hypoxic stimulus mostly resulted in the increased though transient changes in the ventilatory rate at the start and at the end of exercise. This effect seems likely to be mediated by the fast-responding arterial chemoreceptors.

Adult↗