[The use of autologous platelet-rich plasma in the treatment of chronic pharyngitis]. / Primenenie obogashchennoi trombotsitami autoplazmy v terapii khronicheskogo faringita.

The results of a prospective open cohort study of the use of platelet-rich plasma (platelet-rich plasma - PRP) in patients with chronic pharyngitis during the exacerbation of the disease are presented. OBJECTIVE: To evaluate the clinical efficacy of autologous PRP in the treatment of chronic pharyngitis. MATERIAL AND METHODS: Autologous PRP was injected into the posterior pharyngeal wall as a course of endopharyngeal blockages as part of the complex therapy of chronic pharyngitis. Patients in the control group received standard therapy, without the use of autologous PRP. The effectiveness of the studied technique was evaluated by statistical analysis of the intensity of symptoms of the disease, determined by patients throughout the entire period of treatment in the patient's diary, as well as by analyzing data from mass spectrometry of microbial markers and bacteriological examination of the pharyngeal mucosa, collected at the beginning of the study and 14 days after completion of the course of therapy. CONCLUSION: The use of a course of endopharyngeal blockades with autologous platelet-rich plasma as part of the complex therapy of chronic pharyngitis, according to our estimates, provides a significant effect in the form of higher rates of reduction in the severity of symptoms of the disease, a significant reduction in the number of microorganisms deviating from the reference values (by 2 times or more), a decrease in the duration of the disease compared with the control group.

[A new paradigm for the treatment of sternomediastinitis]. / Novaya paradigma lecheniya sternomediastinita.

OBJECTIVE: To analyze the results of simultaneous surgical treatment of sternomediastinitis compared to stage-by-stage approach. MATERIAL AND METHODS: The study included 27 patients between October 2022 and March 2023. All patients underwent heart surgery through median sternotomy. There were 11 (40.7%) women and 16 (59.3%) men. Mean age of patients was 68.4±9.8 years. All patients were divided into 2 groups: 12 patients underwent partial necrectomy and vacuum wound therapy (or long-term dressings) before surgery (group 1), 15 patients underwent surgery without prior conservative treatment (group 2). RESULTS: The most common causative agent of infection was staphylococcus (48.1%). In all patients, we found histological signs of osteomyelitis. Preoperative clinical status was similar in both groups. There were differences in the following indicators: C-reactive protein upon admission - 74.9±18.6 versus 94.8±23.8 mg/l, procalcitonin - 0.13 [0.02; 1.43] versus 0.21 [0.02; 0.94] ng/ml. Postoperative outcomes were similar in both groups. Mortality was 8.3% (n=1) and 13.3% (n=2), respectively. CONCLUSION: Simultaneous combined surgical treatment (sequestrectomy + muscle flap grafting) demonstrates optimal results in the treatment of sternomediastinitis.

Maintenance of the Cardiovascular Function in a Deeply Cooled Homeothermic Organism by Physiological Methods without External Rewarming.

Gradual cooling of homeothermic organisms is followed by slowing and arrest of breathing and heart contractions. During deep cooling, even relatively slight artificial ventilation decreases the lower temperature limit of life (by 4.5-5°C) and provides minimum oxygen supply to the heart and whole body. This allows us to restore cardiovascular function and prevent animal death after lethal cooling without eternal warming.

[Restoration of respiratory function of an organism after cold oppressions without warming].

In experiments on rats studied influence of intravenous introduction NazdTA on respiratory function of rats after the full termination of breath at deep hypothermia. It is shown that such method without warming application it is possible to lower on 1.5-2.0 degrees C a temperature threshold of approach full a cold paralysis of respiratory function of an organism. It confirms the hypothesis put forward earlier about an important role of infringement of balance of ions of calcium in cytoplasm of cells in development of a pathology of an organism at deep hypothermia. The received results can be used at resuscitation of victims accidental hypothermia.

[An increase in efficiency of adaptations and a weakening of organism protective reactions in the process of biological evolution].

The main direction of evolution of living organisms is development of the central nervous system and sense organ, an increase of energy exchange development of homoiothermia, development of the more and more complex forms of behavior, an increase in energy expenditure in connection with an increase of the organism activity, and development of adaptation to the habitat. Such fundamental processes were subjected and have been subjected to numerous studies and discussions. However, in different animals there exist different species peculiarities of evolution of physiological functions, from which finally formed are fundamental evolutionary processes. We studied some of these specific processes by dividing them into two categories. The first category is "Increase of efficiency of adaptation" in development of biological evolution. By this term we mean development of amazing by perfection specific physiological mechanisms of adaptive character. The second category is "Weakening of protective organism reactions". By this we understand disturbance of protective mechanisms of the organism immune system, discoordination of movement of leukocytes along microvessels, the absence of efficient collateral circulation in brain and in heart, etc.

[Modern medical problems of microcirculation and hypoxic syndrome].

In this paper long known problems of microcirculation are shown, which were solved only during the last 40 years. They are concerned with the velocity and character of the capillary blood flow, the regulation of the capillary blood flow, the role of various vessels in the oxygen transport, the role of leukocytes in physiology and pathology of the capillary blood flow, with the special features of the function of lungs in supplying the whole organism with oxygen and with bioenergetic laws in the development of an organism adaptation to hypoxia. Here we considered a number of the most important medical problems of microcirculation and hypoxic syndrome. A relatively new factor in the capillary circulation is the fact that in the brain and heart capillaries there are sites with pO2 close to zero. They show that the capillary circulation has no central nervous regulation of the blood flow. The blood flow in these organs obeys only occasional oscillations. The new fact is that Krogh's rule about metabolism and oxygen exchange occurring only in the capillaries is abandoned. It is shown that almost 30% of consumed oxygen is delivered to the brain via arterioles, which changes our relation to the capillary circulation as a unique mechanism of the tissue supply with oxygen. The new fact is also the mass adhesion of leukocytes to the walls of microvessels, which results in the occlusion of the vessels followed by the development of the heart and brain ischemia. It was shown for the first time that contrary to previous ideas the alveoli in the lungs are supplied with blood from a powerful network of large microvessels from 20 to 50 microm in diameter rather than from thin arterioles. They make possible the passage of 6-121 of the blood in the norm and during stressed muscle activity--up to 18-231 of blood per minute. The principle is substantiated that during hypoxia only normal supply of an organism with oxygen may result in a complete adaptation of an organism to the deficit of oxygen.

[Resuscitation of vital activity after cold arrest of respiration by physiological methods without rewarming the body].

BACKGROUND: The arrest of respiration during deep hypothermia means death, though at a low temperature the heart may rhythmically contract for 30-40 minutes more. The attempts of rewarming only shorten the time before the heart arrest. Calcium ions (Ca2+) are believed to accumulate in the nervous cells in cold. An excess of these ions inhibits the metabolism. Moreover it stimulates the cell proteases, which destroy the cell membranes. AIM: The aim of the study was to make the the attempts to develop the methods of stimulating the respiration and heart without rewarming the body. MATERIALS AND METHODS: The work was carried out on wite rats 250-320g in weight. We introduced disodium salt of ethylenediaminetetraacetic acid into the animals. The second method of blocking the mechanisms of the cold death was artificial respiration. RESULTS: Ethylenediaminetetraacetic acid reacts with calcium ions, decreases their quantity in the blood, and, consequently, in a complex manner in the cell protoplasm. Artificial respiration not only increases the flow of oxygen into an organism but also decreases the lowest temperature threshold of the cold death of an organism. CONCLUSION: A decrease in the surviving threshold by 1.5-1.8 degrees C is very important from the point of view of reanimation of an organism since to preserve life in the critical period of reanimation each 0.5 degrees C are important. Prolongation of minimal frequency of heart contractions and maintaining a minimal arterial blood pressure in an overcooled organism given the body temperature of 11-12.5 degrees C is a special problem of great interest associated with many physiological and biological parameters.

[Physiological problems of alveolar circulation in the lungs].

Since the volume of the blood passing the lungs is great in the norm and especially during stressed muscle activity the question arises about the rate of the blood oxygenation. In the norm, when about 6 1 of the blood passes the lungs per minute, each 500 ml of the blood, which comprises the blood capacity of the lungs, is oxygenated during approximately 5 seconds. During muscle work, when the minute volume of the blood increases to 18-20 1, each 500 ml of the blood are oxygenated during 1-1.5 seconds. It is necessary to reveal the mechanisms of accelerating the blood oxygenation in the alveoli.

[Modern medical problems of energy exchange in humans].

In a living organism 72% of energy exchange occur in the visceral organs, which comprise only 5-6% of the total body mass. The remaining energy is spent at the expense of the skin, bones, connective tissues, resting muscles. The level ofenergy expenditure determines the general physiological state of a human organism, serves for the diagnostics of various diseases, in particular, the diseases of endocrine system, the disruptions of thermoregulation, protein, carbohydrate, and lipometabolism, etc. It should be mentioned that in modern textbooks of physiology, pathophysiology, and biology the problem of energy exchange in humans and animals is given inadequate consideration. Traditionally it occupies only 2-2.5% of the content. Meanwhile, new problems of energy exchange have appeared recently, which almost never were advanced earlier. These are,for example, the reasons and mechanisms of high energy expenditure under conditions of metabolism, the significance of the coefficient of efficiency of a human organism in physiology, special processes previously unknown of the organism heat exchange with the environment, physiological and social components of human energy exchange. There is also a problem of a theoretical possibility of life without energy.

[Critical review of preconditioning].

Adaptation of the brain and myocardium to ischemia by short shutdowns of the regional circulation (preconditioning) is an interesting and important subject. Nowadays it is discussed with animation in the scientific literature. However this problem is very complicated and contains a lot of contradictions. We tried to examine these contradictions and tofind the reasons for this phenomenon.

[Function of alveoles as a result of evolutionary development of respiratory system in mammals].

Reaction of hemoglobin oxygenation is known to occur for 40 femtoseconds (40 x 10(-15) s). However, the process of oxygen diffusion to hemoglobin under physiologic conditions decelerated this reaction approximately billion times. In mammalian lungs, blood is moving at a high rate and in a relatively high amount. The human lung mass is as low as 600 g, but the complete cardiac output approaches 6 1/min. In rat, from 20 to 40 ml of blood is passed for q min through the lung whose mass is about 1.5 g. Such blood flow rate is possible, as in lungs of high animals there exists a dense network of relatively large microvessels with diameter from 20 to 40 microm and more. In spite of a large volume and a high blood flow rate hampering oxygen diffusion, the complete blood oxygenation occurs in lung alveoli. This is due to peculiar mechanisms that facilitate markedly the oxygen diffusion and that developed in alveoli of mammals in the course of many million years of evolution of their respiratory system. Thus, alveolus is not a bubble with air, but a complex tool of fight with inertness of diffusion. It is interesting that in lungs of the low vertebrates, neither such system of blood vessels nor alveoli exist, and their blood flow rate is much lower than in mammals.

New data on the process of circulation and blood oxygenation in the lungs under physiological conditions.

Blood flow through the human lungs weighing 600 g is about 5 to 6 liters per minute. Blood capacity of human lung is about 500 ml. Therefore, 500 ml blood is oxygenated for 5 sec. Questions arise how such a large volume of blood passes through such a small mass of the lungs and what causes very rapid blood oxygenation. Since the structure of the lungs in mammals is almost the same, the work was carried out on rats (in rats 20-22 ml of blood per minute passes through the lungs weighing 1.5-2.0 g). Intensive blood circulation was proved to be linked with a large diameter pulmonary arterioles and high blood flow velocity in them. The oxygenation rate is explained by special structure of the alveoli and special blood flow conditions, which creates ideal conditions for oxygen diffusion.

Circulation in the lungs and microcirculation in the alveoli.

Human lungs weighing ca 600 g permit the passage of 5-6l of blood per minute. The blood capacity of the human lungs is about 0.5 l. Consequently, each 0.5 l of blood is during 5 s. The questions arise of how such a large mass of blood passes through such a small mass of lungs and what the reasons are for such a high rate of blood oxygenation. Since the structure of lungs in mammals is almost the same, we tried to solve these issues studying the rats, in which 20-22 ml of blood pass through the lungs of 1.5-2.0 g mass. A great blood flow appeared to be associated with a large diameter of the lung arterioles and a high rate of the blood flow in them. The high rate of oxygenation is accounted for by a special structure of alveoli and special conditions of the blood flow, which create ideal conditions for oxygen diffusion.

Microcirculation in the lungs: special features of construction and dynamics.

In this study we investigated microcirculation in the lungs in their in situ physiological location inside the thorax. The study was performed with the use of a system of contact optics. A 'window', 4 × 4 mm in size, was made in thorax tissues and pleura of an anaesthetized rat. The lung collapsed and then was filled with oxygen or hypoxic gas mixture under the pressure of 10-15 cm H(2)O through a tracheostomic canula. This almost excluded the respiratory movements of the lung. Then, the lung was brought in contact with a lens (1.7 mm aperture). We showed that there is a whole system of wide microvessels (20-30 µm in diameter) which run between the alveoli; the finding contradicting the hitherto notion that each alveolus is supplied with blood via the thinnest (5-10 µm in diameter) lung arterioles. The microvessels we visualized surround each alveolus almost from all sides. In this way, each alveolus receives a maximum amount of blood. Such a structure of lung circulation accounts for a substantial blood flow through the lungs (up to 6 l per min in humans) and for a rapid saturation of the blood with oxygen (about 100 ml per second). The alveoli saturate the blood with oxygen and subsequently the microvessels form the lung veins entering the left auricle. The photographs and video films of the alveoli at a high magnification were presented, demonstrate the special features of the structure and circulation in the alveoli. The plausible mechanisms of rapid saturation of the blood with oxygen are discussed.

[Diagnostic capabilities of single-photon emission computed tomography/computed tomography in the evaluation of perfusion disorders in pulmonary hypertension].

OBJECTIVE: to study the diagnostic capabilities of single-photon emission computed tomography/computed tomography (SPECT/ CT) in the evaluation of lung perfusion in pulmonary hypertension (PH). SUBJECT AND METHODS: Ten patients with pulmonary hypertension were examined. Its diagnosis was verified in accordance with the Russian guidelines for the diagnosis and treatment of PH, by conducting a set of studies involving right heart catheterization. CT angiopulmonography was carried out in all the patients. At the same time all the patients underwent a radiological study on a combined SPECT/CT scanner with the intravenous injection of the radiotracer 9mTc-MAA (technetium-99m-labelled macroaggregated albumin) with an activity of 2-4 mCi. RESULTS: CT-angiopulmonography revealed no thrombi in the pulmonary artery lumen in 7 patients and confirmed the diagnosis of pulmonary thromboembolism (PTE) at the level of segmental vessels in 3. SPECT/CT examination identified 5 cases of non-thromboembolic PH and 5 cases of PTE with consideration for SPECT perfusion defects and no visible lung tissue (fibrous or other) changes on a CT scan. It should be noted that the 5 patients diagnosed as having PTE included 2 patients in whom PTE had not previously been diagnosed at CT angiopulmonography. This may be due to that this technique cannot always clearly visualize thrombi in the pulmonary vessel lumen at a subsegmental level. CONCLUSION: The inivestigations have indicated that, by clearly ivisualizing pulmonary aanatomy, morphology, and function, combined SPECT/CT imaging is a valuable diagnostic tool in detecting lung pathology.

[Brain hypoxia and the role of active forms of oxygen and of energy deficit in the neuron degeneration].

The concepts about physiological mechanisms of oxygen transport to the brain have recently changed substantially. Precise data on the capillary blood flow rate, on a substantial dispersion of corresponding values, on the influence of the capillary blood flow rate on pO2 in the capillaries and tissues have evolved. Krog's paradigm about an exclusive role of capillaries in the gas exchange between the blood and tissues amounting to almost 100 years was abandoned. All these data also changed the concepts about the development of various types of hypoxia in the brain tissues. The study of pO2 in the brain at normoxia showed that pO2 exhibits the fluctuations from 1-2 to 80-85 mm Hg. This means, in particular, that hypoxic phenomena take place in the normal healthy brain. During hypoxia the mass adhesion of leukocytes to the walls of microvessels was shown to hamper the capillary blood flow and can become one of the reasons for the death of the brain during hypoxia. The brain hypoxia is not an occasional pathologic process. It exists in an intact brain owing to physiological fluctuations of pO2 in various microregions of the brain. It occurs during various physiological states in the norm and also during various illnesses associated with the changes and disruptions in the oxygen transport. The final stage of hypoxia is the destruction of the cells. The development of this process and its particular reasons are nowadays the subject of multiple physiological and biochemical studies. Certain changes are introduced into modern ideas about the reasons for the degradation of the nervous cells upon hypoxia. The degradation of the neurons during hypoxia or anemia is postulated to be associated not only with the cell generation of active forms of oxygen (AFO), but also with the energy deficiency. This means a deficient synthesis or a complete absence of ATP in a cell during hypoxia, anemia, and ishemia.

Blood circulation in rat lungs under conditions of reduced oxygen level in inhaled air.

According to some authors, reduction in oxygen level in the lung alveoli results in constriction of afferent vessels, while others observed no vessel constriction. The issue is of principle importance in relation to the lung involvement in body adaptation to hypoxia. Conventional methods are inefficient to solve it, therefore we used a contact microscope allowing observation of lung circulatory system structure and condition of the lung circulatory system in whole, virtually intact animal, on whole undamaged lungs in situ, at normal physiological lung position in the thorax. We found that large vessels carrying blood to the alveoli do not constrict or dilate at reduced Po(2)in lung alveoli. These vessels with a diameter of 15 to 40 µ and more are the only blood source for alveoli.

[Morphodynamic analysis of lung microcirculation (a supravital morphological study)].

Using the system of contact optics, the circulation (microcirculation) was studied in the lungs of 15 adult Wistar rats during the normal physiological location of the organs inside the thorax. A 4x4 mm "window" was made in the tissues of the thorax of an anaesthetized rat, through which the pleura was incised, resulting in the lung collapse. The lung was filled with oxygen or hypoxic gas mixture under the pressure of 10-15 cm of water column through a tracheotomic cannula. Then the lung was brought in contact with the contact objective aperture (1.7 mm in diameter). Each alveolus was supposed earlier to be supplied with blood via a thinnest (5-10 microm in diameter) lung arteriole. The present study has shown that there exists a system of wide (20-30 microm in diameter and larger) microvessels, which run between the alveoli. These microvessels surround each alveolus, practically, from all the sides. In such a manner each alveolus is supplied by a maximal amount of blood. Such a structure of the lung circulation system accounts for a great blood flow through the lungs (up to 6 1 per minute in humans) and a rapid saturation of the blood with oxygen.

[Cold pathology and experimental therapy of deep hypothermia].

A complete cold paralysis of respiration and thermoregulation occurs in rats at the temperature in the brain 16.6 +/- 0.3 and in the rectum 15.2 +/- 0.3 degrees C. Under the conditions of room temperature 18-19 degrees C, the respiration never restores, and the animals die. This is believed [6] to be the result of calcium ion Ca2+ accumulation in the cells of respiration and thermoregulation centers. After the arrest of respiration the animals were injected with the solution of disodium salt of ethylenediaminetetraacetic acid (Na2EDTA), which binds calcium ions in the blood and facilitates their removal from the cell (explanations in the text). In 7-9 min after the injection the calcium content in the blood decreased and the respiration began to restore at the temperature of the cold paralysis. Thermoregulation was also restored. All the test animals survived. All the control animals, which were not injected with Na2EDTA, died.