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Aim. To study features of tissue oxygenation and changes in nitroxidergic and endothelinergic mechanisms of circulation regulation in ischemic stroke and hypoxia modeling. Methods. 74 men and women with ischemic stroke were examined and experimental study on 30 outbred white male rats was conducted. All patients underwent computed tomography of the brain, neurological status was assessed and general clinical examination was performed. Tissue oxygen tension was measured percutaneuosly using polarographic method. Chronic hypoxic hypoxia was simulated in animals by daily 40-50 minutes inhalation of 10% oxygen mixture for 4 weeks. Blood oxygen tension was evaluated in patients and laboratory animals. Nitric oxide level of was assessed by determining its stable metabolites. Endothelin-1 level was determined by ELISA. Data was analyzed using «Statistica 8.0» software using non-parametric tests. Differences were considered as statistically significant at p

Aim. To study the role of nitroxidergic reactions of the circulatory system in the development of ischemic stroke. Methods. 51 patients (both males and females) with the diagnosis of ischemic stroke were examined. All patients were distributed to 3 groups according to the severity of neurological deficit. All patients underwent brain computed tomography or magnetic resonance imaging. Cerebral blood flow was examined by extra and transcranial ultrasonic dopplerography. Central hemodynamics was evaluated by echocardiography. General clinical examination, neurological and neuroophthalmological examinations were also performed. Vasomotor endothelial function was assessed using a 7 MHz linear transducer on the ultrasound unit «Medison SonoAce X8». The level of nitric oxide was assessed using its stable metabolites, nitrite and nitrate definition in serum. Neurological status was assessed according to the USA National Institutes of Health Stroke Scale. Results. Disorders of nitroxidergic mechanisms of blood vessels regulation were observed in patients with ischemic stroke. Endothelium-dependent brachial artery dilation disorders and nitric oxide persistent metabolites level decrease were related to the severity of the disease and the neurological deficit degree. Conclusion. The study of endothelium-dependent vascular tone regulation mechanisms revealed that these mechanisms are involved in the pathogenesis of ischemic stroke; the study of these mechanisms can be used to clarify the severity of neurological deficit, and possible prognosis.

To study the possibility of applying methods of mathematical modeling in assessing the severity of ischemic stroke in patients with arterial hypertension.The study included 80 patients with ischemic stroke. Blood pressure was measured. Transcutaneous polarography was used to measure the oxygen tension in tissues. Measurements of gas composition of the blood and thickness of the intima-media complex were performed. The level of stable metabolites of nitric oxide in the blood was determined. Measurement of endothelin-1 in the blood was performed by enzyme immunoassay. NIHSS scale was administered to assess the neurological status. Patients were divided into 3 groups according to the degree of neurological deficit. The control group consisted of 10 people without signs of vascular pathology.An increase in the neurological deficit was accompanied by an increase in the level of endothelin-1, a decrease in the level of stable metabolites of nitric oxide, and a reduction in tissue oxygenation. Discriminative functions were developed for each group of patients using discriminant analysis based on the data obtained in the study. The most statistically significant were two signs: the level of systolic blood pressure and the content of stable metabolites of nitric oxide in the blood.Thus, the imbalance in the indices of endothelium-dependent mechanisms of vascular tone regulation reflect the severity of the condition in ischemic stroke. The method of discriminant analysis allows the creation of sufficiently reliable mathematical models that can have practical significance, and can be used as a method of clarifying the severity of the condition in the acute period of ischemic stroke.Цель исследования. Изучить возможность применения методов математического моделирования в оценке тяжести ишемического инсульта (ИИ), развившегося на фоне артериальной гипертензии. Материал и методы. В исследование включены 80 пациентов с ИИ. Измеряли уровень артериального давления и с помощью чрезкожной полярографии - напряжение кислорода в тканях. Проводили исследование газового состава крови и измерение толщины комплекса интима-медиа. Определяли уровень стабильных метаболитов оксида азота в крови. Измерение уровня эндотелина-1 в крови выполняли иммуноферментным методом. У всех пациентов исследовали неврологический статус с оценкой по шкале NIHSS. Пациенты были разделены на 3 группы по степени выраженности неврологического дефицита. Контрольную группу составили 10 лиц без наличия признаков сосудистой патологии. Результаты. Выявлено, что с нарастанием неврологического дефицита происходит рост уровня эндотелина-1, понижение уровня стабильных метаболитов оксида азота и снижение показателей оксигенации тканей. С помощью дискриминантного анализа на основании полученных в исследовании данных были разработаны дискриминативные функции для каждой группы пациентов. Наиболее статистически значимыми оказались два признака: уровень систолического артериального давления и содержание стабильных метаболитов оксида азота в крови. Заключение. Дисбаланс в показателях эндотелий-зависимых механизмов регуляции тонуса сосудов отражает тяжесть состояния при ИИ. Метод дискриминантного анализа позволяет создавать достаточно достоверные математические модели, которые могут иметь практическое значение и использоваться как метод уточнения тяжести состояния в остром периоде ИИ.

To examine effects of endotheline-1 (ET-1) and nitric oxide (NO) on endothelium-dependent mechanisms of vascular tonicity regulation in patients with chronic cardiac failure (CCF) of FC I-IV (NYHA).Vascular reactions of 94 patients with CCF of FC I-IV were examined according to D.S. Celermajer method using ultrasound of high resolution. Tissue oxygenation was studied with transcutaneous polarography (TCM-2, Radiometer). Parameters of circulating erythrocytes were studied by impurity spectrum. Endothelial NO-synthase expression was determined with application of monoclonal antibodies to endothelial NO-synthase. NO metabolites were studied with colorimetric method using Griss reagent. ET-1 was measured in plasma by enzyme immunoassay. The control group consisted of 28 healthy men aged 20 to 54 years.Patients with CCF of FC I-IV have reduced endothelium-dependent vascular reactions progressing with aggravation of CCF. The causes of the disorders lie in altered metabolism of ET-1 and NO in CCF.CCF patients demonstrate changes in endothelium-dependent mechanisms of vascular tonicity regulation caused by disturbed metabolism of ET-1 and NO developing in abnormal regime of tissue oxygenation and depending on CCF severity.

By taking into account the state of the central nervous system (CNS), anthropometric indices, and the mode of artificial ventilation (AV), the authors used original procedures for estimating the values of respiratory performance and the mechanics of respiration in order to study the specific features of ventilatory disorders in 510 patients (378 males and 132 females) with CNS injuries and diseases, who developed respiratory failure requiring AV for more than 24 hours. Four types of respiratory rhythm regulation, which are of different prognostic value, were identified. These included apneic (100% mortality), hypopneic (44%), normopneic (0%), and hyperpneic (53.3%) types. The authors have established a relationship of impaired respiratory regulation and respiratory muscle weakness to the severity and extent of CNS lesion; that of the development of obstructive and restrictive disorders to the extent and severity of CNS lesion and age; a role of acute lung lesion (ALL), pneumonia, and endobronchitis in the impairment of respiratory mechanics. They have also found that restrictive disorders accompany obstructive disorders and ALL in all forms of CNS lesions and that there may be, under AV, ALL without restrictive disorders, regression of all degrees of thoracopulmonary restriction and ALL.

The authors elaborated an algorithm of respiratory management (RM) based on the correlation of RM parameters with the actual and proper thoracopulmonary compliance (C). The algorithm was tested on 42 patients with affections of the central nervous system (CNS) due to severe craniocerebral trauma, spinal trauma, cerebral stroke and multitrauma. Thirty-nine case-matching patients where in the control group--the routine RM algorithm was used for them. Mean pressure in the respiratory paths (Pmean, C, PaO2/FiO2 and rSO2 readings by the Glasgow coma scale, cerebral perfusion pressure, and consumption of sedatives, muscle relaxants and vasopressins as well as frequency rate of acute pulmonary lesions (APL) were registered. The RM algorithm provided for a more effective prevention and treatment of APL versus the routine RM--it cut, 3-fold, the remote APL. With the above RM algorithm, the need in sedatives, muscle relaxants and vasopressins went down from day 2. Positive trends in the neurological status as well as normalized rSO2 were observed earlier versus the controls. Finally, its use ensured a more favorable treatment outcome.

Sixty-one patients with severe craniocerebral injuries were examined on days 1-3 after the injury. Consciousness was no more than 8 points by the Glasgow Coma Scale. The patients were divided into 2 groups: 1) favorable outcomes and 2) unfavorable outcomes. Gaseous composition of arterial and venous blood was analyzed in all patients, intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were measured, artificial ventilation of the lungs (AVL) and noninvasive monitoring of cerebral oxygenation (CO) were carried out. The results indicate that continuous monitoring of CPP and CO helps control the time course of cerebral blood flow, thus promoting early detection and effective treatment of cerebral ischemia in critical patients.

Investigation of pulmonary hemodynamics were carried out in 26 victims operated on for brain compression with intracranial (epi-, subdural, and intracerebral) hematomas in combination with severe contusions during different regimes of artificial ventilation of the lungs (VCV, VCV + PEEP, PCV). Intracranial pressure and cerebral perfusion pressure were evaluated. The results indicate that in patients with severe craniocerebral injury PCV decreased systolic pulmonary artery pressure, total pulmonary resistance, central venous pressure, intracranial pressure, increased cerebral perfusion pressure, and therefore the pressure cyclic mode is pathogenetically validated in this patient population.

Gamma-topography of the abdominal region and radiometry of duodenal aspirates were used for examination of 707 patients with different gastroenterological pathology using various modes of the administration of 75Se-methionine (intravenously, per os, into the duodenal and cecal lumens, intra-arterially in the celiac trunk and superior mesenteric artery). The RP administered intravenously was accumulated in health in the liver and pancreas. The drug fixation by the proximal part of the jejunum was also typical of chronic pancreatitis, the degree of fixation being well correlated with a period of disease. A jejunum image on gamma-topograms proved to be determined not by radioactivity of the jejunum in passage of labeled pancreatic juice but by extraction of the radionuclide from the blood by its wall. In transduodenal administration of the radionuclide its major part was rapidly absorbed and accumulated in the liver. At the same time a considerable part of the drug remained at the site of administration and retained there for several days. There was almost no absorption of the drug in the cecum and ascending colon. Like in the duodenum, the drug retained at the site of administration for a long time. Intestinal extravasal trophicity was assumed.