Hemic Hypoxia Research Articles

Influence of new dimethylaminoethanol derivatives, butanoic and trans-butenedioic acids, on the tolerability of hypoxia, hyperthermia, and hypothermia

BACKGROUND: The need to increase the tolerance of various extreme effects is associated not only with the expansion of human professional activity regions but also with the need to assist victims of natural and man-made disasters. The use of pharmacological agents for individual adverse effects is a well-known method; however, considering the combined effects of several physical or chemical factors, only a few references are found in the literature.
 AIM: This preclinical study aimed to examine the effectiveness of a new derivative of aminoethanol and intermediates of the Krebs cycle in relation to the isolated and combined effects of hypoxia and temperature (hyperthermia and hypothermia).
 MATERIALS AND METHODS: The fumaric salt of the amber ether of diethylaminoethanol was synthesized at St. Petersburg State University of Chemistry and Pharmacy, Department of Organic Chemistry (Head Professor I.P. Yakovlev). The study was conducted on small laboratory animals. Resistance to hypoxia was assessed by the dynamics of the altitude threshold of animals, tolerance to hyperthermia by survival in a thermal chamber at 40°C, and tolerance to hypothermia by the time of maximum swimming in water at 10–12°C. Under combined exposure, the condition of the animals was assessed by the dynamics of physical performance, hypoxia was induced by preliminary administration of the methemoglobin former sodium nitrite at a dose of 50 mg/kg, and thermal exposure was induced by placing the animal in water at 40°C (hyperthermia) or 9–11°C (hypothermia).
 RESULTS: After a single intragastric administration in a wide range of doses, the test compound stimulated the physical performance of animals and exhibited a protective effect under the isolated effects of hypobaric hypoxia, hyperthermia, and hypothermia. With combined exposure to hemic hypoxia and hyperthermia, the compound was effective at a dose of 250 mg/kg. With combined exposure to hemic hypoxia and hypothermia, efficiency was also noted at lower doses (25 and 50 mg/kg).
 CONCLUSION: Fumaric salt of dimethylaminoethanol amber ether, a new derivative of dimethylaminoethanol, butenedioic, and trans-butenedioic acids, is promising for further study as a means of increasing the body’s resistance to extreme influences.

Histomorphological studies of myocardium under the influence of pharmaceutical composition based on L-carnitine in the model of moderate hemic hypoxia

Histomorphological studies of myocardium under the influence of pharmaceutical composition based on L-carnitine in the model of moderate hemic hypoxia

The condition of electrolyte homeostasis in children with hereditary hemolytic anemia

Objective. Determine the content of electrolytes in the blood serum depending on the severity of anemia in children with hereditary hemolytic anemia.Material and methods. Observations were made on 36 children with hereditary hemolytic anemia (NGA) aged between 3 to 14 years. The distribution by gender was as follows: 16 girls (44.5%) and 20 boys (55.5%). The average age of the participants during the study was 9.5±0.45 years. These children were categorized into three groups based on anemia severity. Primary school-aged children formed the majority, followed by preschoolers, with senior school-aged children being the least in number. Upon admission to the clinic, a thorough examination of each child was conducted, encompassing a detailed complete blood count, erythrocyte morphology, biochemical blood tests (measuring total bilirubin and its fractions), blood serum electrolyte levels (K+, Na+, Ca+, Fe+), and an analysis of bone marrow punctate.Results and discussion. Electrolyte analysis yielded these findings: In children with mild HHA (14 patients), compared with the control group, the concentration of blood electrolytes (K+, Na+, Ca+, Fe+) were within the normal range. In children with moderate HHA (12 patients), the concentration of Fe+ was slightly higher compared with the control and the first group, respectively, and there was also a slight increase in the concentrations of K+, Na+, Ca+ compared with healthy children and children with mild HHA. In children with severe HHA (10 patients), as a result of the development of a hemolytic crisis, the concentration of electrolytes in the blood serum is significantly higher than K+, Na+, Ca+, Fe+ compared with children in the control group K+, Na+, Ca+, Fe+ and patients with mild and moderate, respectively.Conclusion. The study revealed significant clinical changes in the internal organs, as well as pronounced metabolic disorders in the body, due to chronic hemic hypoxia and impaired blood electrolyte composition.

Lipid Nanoparticles for Lutein Encapsulation and Delivery

Recently, lipid nanoparticles have been intensively studied as carriers of lipophilic drugs. In this work, we have studied the stability of nanoemulsions with paraffin oil, solid lipid nanoparticles with stearic acid, and nanostructured lipid particles with paraffin oil and stearic acid in a mass ratio of 1 : 1. The obtained results have shown that all studied lipid systems stabilized with nonionic surfactants Tween 60 and Span 60 were stable to aggregation and subsequent sedimentation for more than 30 days. The incorporation of lutein into the lipid particles has almost no effect on their stability, while the size of solid lipid nanoparticles and nanostructured lipid nanoparticles decreases from 28–30 to 15–17 nm. The bioavailability of lutein loaded in lipid nanoparticles is evaluated from their effect on the restoration of blood flow velocity by simulating hemic hypoxia. Almost immediately after the application of lipid nanoparticles, the blood flow velocity ceases to decrease, and a tendency to its restoration is observed in 5–10 min. This shows that lipid nanoparticles with paraffin oil and stearic acid are promising candidates for the delivery of lipophilic drugs.

Некоторые аспекты этиопатогенеза формирования анемической кардиомиопатии

The review article presents some issues of the etiopathogenesis of the formation of anemic cardiomyopathy. According to various sources, the pathogenetic onset of anemic cardiomyopathy should be considered a decrease in oxygenation or hemic hypoxia, which in the first stages is accompanied by the development of compensatory mechanisms. With the development of severe forms of anemia, systemic vascular resistance and afterload on the left ventricle significantly increase and lead to a decrease in the ejection fraction of the left ventricle, which subsequently leads to the formation of cardiac pathology in the form of “anemic cardiomyopathy”.

THE EFFECT OF HEMIC HYPOXIA THAT OCCURRED IN RATS WITH NITRITE-INDUCED DEMENTIA ON THE DYNAMICS OF BIOCHEMICAL INDICATORS OF ENERGY METABOLISM IN BRAINS

Have been considered the role of hemic hypoxia, which arose against the background of nitrite-induced dementia of the Alzheimer type in rats on the dynamics in biochemical indicators of energy metabolism, the degree of hypoxia, the content of acetylcholi

Chemical composition and cardiotropic activity of Ziziphora clinopodioides subsp. bungeana (Juz.) Rech.f.

Ethnopharmacological relevanceZiziphora clinopodioides subsp. bungeana (Juz.) Rech.f. is a subshrub that is widely distributed in China, Kazakhstan, Kyrgyzstan, Mongolia, Russia, Tajikistan, Turkmenistan, and Uzbekistan. The species is used in traditional medicine for the relief of symptoms connected to cardiovascular diseases like coronary heart disease or hypertension. Aim of the studywas to validate traditional use of Z. clinopodioides subsp. bungeana for the treatment of coronary hearth diseases using in vivo models and to find active compounds responsible for the activity. Materials and methodsMultiple extracts were obtained from the aerial parts of Z. clinopodioides subsp. bungeana using maceration, liquid-liquid extraction, CO2 extraction and ultrasound-assisted extraction. Preliminary screening studies for the evaluation of the efficacy of Z. clinopodioides subsp. bungeana extracts on the model of hemic hypoxia were performed. The most effective samples were selected and included in the main study. Stage 2 of the study evaluated the cardiotropic activity of the selected extracts on a model of chronic heart failure. Preparations were administered to animals intragastrically once a day for 28 days. For the isolation of individual compounds plant material was extracted with 96% ethanol. The obtained crude extract was sequentially extracted with n-hexane and dichloromethane and separated by chromatography on a Diaion HP-20 column. The obtained fractions were further subjected to Sephadex LH-20 column chromatography and eluted isocratically with 96% ethanol (EtOH) to yield subfractions, which were further separated by preparative HPLC to obtain 13 individual compounds. ResultsExtracts obtained from Ziziphora clinopodioides subsp. bungeana (Juz.) Rech.f. herb were subjected to pharmacological screening for the evaluation of their efficacy on hemic hypoxia. Based on the obtained results, out of the sixteen tested extracts two (AR and US 60%) were selected for further evaluation of their cardiotropic activity. Modeling of chronic heart failure was carried out in accordance with the following stages: 1) anesthesia with chloral hydrate at a dose of 450 mg/kg, intraperitoneally, 2) artificial ventilation of the lungs, 3) thoracotomy, 4) modeling of permanent ischemic or ischemic-reperfusion damage. Both extracts effected the indicators of contraction and output, comparable to the reference drug - Monopril. Based on the extraction methods used to obtain RAF and US60 and data from the literature, it can be assumed that they contain compounds with medium polarity, including polyphenols and terpenoids. At the next stage three previously undescribed monoterpenoid derivatives – Ziziphoric acid (1), Ziziphoroside D (2) and 6′-malonylziziphoroside A (3), along with two previously described megastigmane glucosides – blumenol C glucoside (4), blumenol C 9-O-(6′-O-malonyl-beta-D-glucopyranoside (5) and two previously described monoterpenoids 7a-hydroxymintlactone (6), 7-hydroxypiperitone (7) together with six polyphenols – pinocembrine-7-O-rutinoside (8), chrysine-7-O-rutinoside (9), acacetin-7-O-rutinoside (10), luteolin-7-O-rutinoside (11), rutin (12) and rosmarinic acid (13) were isolated from Z. clinopodioides subsp. bungeana extracts. ConclusionOur results support the traditional use of Z. clinopodioides subsp. bungeana for the treatment of coronary diseases. As a result of Z. clinopodioides subsp. bungeana extracts screening in vivo, two extracts were selected as potential cardiotropic agents. Phytochemical analysis of the plant material led to the isolation of five terpenoid derivatives, two megastigmane glycosides, five flavonoids and one cinnamic acid derivative, which could be responsible for the reported biological activity. Future experiments are required to understand the mechanisms of action for the isolated compounds.

ИССЛЕДОВАНИЕ ПРОТИВОГИПОКСИЧЕСКОЙ АКТИВНОСТИ НОВОГО СОЕДИНЕНИЯ ЛХТ 3-21 В ЭКСПЕРИМЕНТАХ НА ЖИВОТНЫХ

In experiments with mice under various models of acute hypoxia a new synthesized compound LKhT 3-21 (50 mg/kg) showed a distinct antihypoxic activity. In comparison to mexicor (50 mg/kg), this compound increased lifespan in a hermetic chamber, under hemic hypoxia and histotoxic hypoxia by 107 %, 47 %, and 70 %, respectively. LKhT 3-21 exceeded mexicor in the effect against acute normobaric hypoxia with hypercapnia (in 1.9 times), acute hemic hypoxia (in 1.4 times) and acute histotoxic hypoxia (in 1.6 times).

Pathophysiological aspects of the interaction of hypoxia and physical load (experimental study)

Background. A typical extreme factor is hypoxia, which significantly affects the ability to perform tasks of professional activity, in particular, physical activity of various intensity. Physical and neuro-emotional stress under conditions of hypoxia can cause the breakdown of compensatory and adaptive mechanisms with the development of extreme and critical conditions.The aim of the study. Quantitative assessment of the effect of hypoxia on the physical performance of laboratory animals at different levels of their natural resistance.Research methods. Modeling of hypoxia was carried out by the methods of pressure chamber rise of laboratory animals and the administration of a methemoglobin former. Resistance to hypoxic hypoxia was assessed by the criterion of the threshold elevation, to hemic hypoxia – by the lifetime. The criterion for the functional state of laboratory animals was their ability to perform physical activity, which was created by treadmill run or swimming with a load.Results of the study. An altitude of 3500 m causes a decrease in the physical performance of male rats by a third of normoxia level; an altitude of 5000 m – decrease by two times; an altitude of 6500 m – decrease by four times, and at an altitude of 8000 m makes running physical activity by rats impossible. A mild degree of hemic hypoxia causes a decrease in swimming time by almost 2 times, which corresponds to the effect of an altitude of 5000 m on the working capacity; and a moderate degree of hemic hypoxia causes a decrease in swimming time by more than 3 times, which approximately corresponds to the effect of an altitude of 6000 m. The level of resistance to hypoxia has a moderate effect on physical performance, and the factor of a low level of physical performance has almost no effect on the resistance to hypoxia (28 % and 7 % of the trait variability respectively). In animals with an initially low level of resistance to hypoxia, there is also a decrease in working capacity by an average of 20 %.Conclusion. Hemic hypoxia is an adequate model in studies with a complex effect of various extreme factors. Simulation of mild hypoxia caused by the administration of 30 mg/kg of sodium nitrite is an optimal method.

Synthesis and antihypoxic activity of new diphenylguanidine derivatives

Previously undescribed derivatives of diphenylguanidine were obtained, structure and individuality of which have been proven by 1 H, 13 C NMR, IR, X -ray structural analysis, elemental analysis and mass spectrometry. For all compounds, an in vivo study of antihypoxic activity was carried out on a model of acute hemic hypoxia. High antihypoxic activity of 2,5-dioxo- N,N' -diphenylpyrrolidine-1-carboxymidamide was revealed, exceeding the strength of the comparison drug - mexidol.

Antihypoxic activity and anti-ischemic effect of complex herbal remedy

The present study was carried out to determine the antihypoxic and anti-ischemic effects of a polyherbal extract from Astragalus membranaceus, Scutellaria baicalensis and Phlojodicarpus sibiricus. The Wistar rats of both sexes were used in the study. The antihypoxic activity of the extract was studied using hemic and hypobaric models of hypoxia. The anti-ischemic effect of the extract was evaluated by the severity of neurological deficit and survival within 24 hours in model of bilateral occlusion of the common carotid arteries.
 The course administration of the extract (100, 200 mg/kg) had an antihypoxic effect in the model of hemic hypoxia: the reserve time of life increased by 26 and 28%, respectively, compared with the control. The course introduction of the extract at doses of 50, 100 and 200 mg/kg increased the reserve time of life in hypobaric hypoxia by 12.3, 15.5 and 16.7%, respectively, compared with the control
 The administration of the extract (100 and 200 mg/kg) in the model of cerebral ischemia had a cerebroprotective effect: the indicators of neurological deficit were, respectively, less than the control by 34 and 46%, and their survival was 62 and 64%, respectively, against 20% of the survival of rats in the control group. The results of the conducted studies suggest the prospects for further study of the plant extract as a cerebroprojector agent.

PATHOPHYSIOLOGY OF MOLECULAR HYDROGEN INFLUENCE ON ACUTE KIDNEY DAMAGE IN HEMIC HYPOXIA

When hemoglobin is inactivated by nitrites, hypoxia of the renal tubules is not accompaniedby inhibition of renal blood circulation. At the same time, the fi ltration fraction of sodiumions and the load on the energy- dependent mechanisms of the proximal and distal tubules remain high, but since there is no energy, signifi cant reactions of damage to the proximalnephron and dysfunction of the distal tubules as reabsorption of sodium than in theproximal tubule are observed. To correct the detected disorders, it is advisable to usean antioxidant solution of negative redox potential with hydrogen saturation, whichcan penetrate into cells, reach mitochondria, penetrate areas of ischemia, edema andinfl ammation, improve energy supply by means of supplying additional electrons anddetecting neutralization of hydroxyl radical and peroxynitrite.Purpose – to determine the eff ect of an antioxidant solution of negative redox potentialwith molecular hydrogen saturation on the functional and biochemical processes of thekidneys in acute hemic hypoxia of moderate severity.Materials and methods. The experiments were performed on 30 white nonlinear malerats weighing 0.16-0.18 kg under the conditions of hyposodium diet. Simulation ofexperimental hemic hypoxia was performed by a single subcutaneous injection of 1%sodium nitrite solution at a dose of 50 mg / kg body weight, causing, respectively, theaverage severity of hemic hypoxia. An antioxidant solution of negative redox potentialwith hydrogen saturation 1.0-1.2 ppm and redox potential –297.3 ± 5.27 mV was obtainedusing a new generation generator Blue Water 900 (Korea). Experimental, physiological,biochemical, immunoenzyme, histoenzymo- chemical and statistical research methodswere used.Results. The development of acute hemic hypoxia of moderate severity was accompaniedby an increase in glomerular fi ltration, protein excretion, decreased distal reabsorptionof sodium ions. An increase in the concentration of tumor necrosis factor- alpha in bloodplasma was found and an increase in unlimited proteolysis in the kidneys was detected:by azocollagen lysis in the cortex, azocasein in the medullary substance and azoalbuminin the papilla. Moderate hemic hypoxia showed an increase in the concentration of lipidperoxidation products: malonic aldehyde and diene conjugates in the renal medulla andinhibition of succinate dehydrogenase activity in the proximal nephron (p <0.01). Theuse of a solution of negative redox potential with molecular hydrogen saturation hada corrective eff ect on the studied parameters.Conclusions. 1. In acute hemic hypoxia of moderate severity, a solution of negative redoxpotential with molecular hydrogen saturation due to its antioxidant, cytoprotective, energyproperties improves the condition of the proximal tubule, reduces the manifestations ofproteinuria (p <0,01), increases tubular type succinate dehydrogenase activity (p <0.02)in this part of the nephron. 2. The use of a solution of negative redox potential withmolecular hydrogen saturation due to its antioxidant, anti-infl ammatory, nephroprotectiveproperties has a protective eff ect on the kidneys and reduces elevated levels of tumornecrosis factor- alpha in blood plasma (p <0,01), lysis azocollagen, azoalbumin, azocaseinand lipid peroxidation products of malonic aldehyde (p <0.01) and diene conjugates inacute hemic hypoxia of moderate severity.

Истинная степень гемической гипоксии в определении тяжести отравления монооксидом углерода: клиническое наблюдение

Актуальность. Отравление монооксидом углерода является наиболее часто регистрируемой интоксикацией ядовитыми газами. Ранее авторами было выявлено, что наибольшее число отравлений монооксидом углерода в 2015 году произошло по причине пожаров, на втором месте — неисправные системы вентиляции. Цель исследования: улучшение результатов лечения отравления монооксидом углерода посредством более точной диагностики тяжести отравления. Материалы и методы. Анализ клинико-анамнестических и лабораторных данных пострадавших в результате массового отравления монооксидом углерода. С применением показателя «эффективный оксигемоглобин» уточнена степень тяжести отравления. Проведен обзор и анализ доступной литературы, включая данные из базы PubMed. Результаты. Причиной отравления монооксидом углерода послужило нарушение правил эксплуатации бытовой газовой колонки, в результате чего пострадали семь человек (один ребенок госпитализирован в профильный стационар). К значимым клиническим особенностям нами отнесено следующее: относительная тахикардия отмечалась у всех пострадавших, патологические изменения на электрокардиографии выявлены именно у пострадавших с наиболее тяжелой неврологической симптоматикой. В дальнейшем на основании уровня карбоксигемоглобинемии на момент поступления в стационар происходило занижение на один ранг тяжести отравления, установленной клинико-анамнестически. В результате поиска объяснения такого расхождения на основании сведений о повышении сродства гемоглобина к кислороду в условиях карбоксигемоглобинемии авторами предложен расчетный показатель — эффективный оксигемоглобин. После расчета у всех пострадавших эффективный оксигемоглобин соответствовал гемоглобину при анемии легкой степени. Таким образом, применение показателя эффективного оксигемоглобина позволило уточнить тяжесть отравления монооксидом углерода, выявленную лабораторно, что повысило обоснованность клинико-анамнестической оценки. Выводы. При определении тяжести отравления монооксидом углерода ранняя оценка истинной степени гемической гипоксии посредством показателя эффективного оксигемоглобина позволит повысить обоснованность прогноза заболевания и улучшить результаты лечения таких пострадавших.

ANTIHYPOXIC ACTIVITY OF 2,6-DIMETHYLPYRIDINE-N-OXIDE.

The aim: To study the antihypoxic activity of 2,6-dimethylpyridine-N-oxide in mice using the various experimental models of acute hypoxia under orally or intraperitoneally administration. Materials and methods: The studies were performed on male CD-1 (SPF) mice. The antihypoxic activity of 2,6-dimethylpyridine-N-oxide was studied in three experimental models of acute hypoxia - hypercapnic hypoxia or hypoxia in a closed space, hemic hypoxia and histotoxic hypoxia at orally administration at doses 0.07; 7.1 and 71 mg/kg (respectively 1/20000, 1/200 and 1/20 of LD50) and at intraperitoneally administration at doses 7.1 and 71 mg/kg in comparison with reference drug Armadin. Results: It is established, that 2,6-dimethylpyridine-N-oxide shows a antihypoxic activity in the all experimental models of acute hypoxia (hypoxia in a closed space, hemic hypoxia and histotoxic hypoxia). Its antihypoxic activity in acute hemic hypoxia and in acute hypoxia in a closed space was significantly higher than of reference drug Armadin, but during acute histotoxic hypoxia did not differ from Armadin. Also at intraperitoneal administration of 2,6-dimethylpyridine-N-oxide demonstrates less pronounced antihypoxic activity than at oral administration in all experimental models of acute hypoxia, but the coefficient efficiency is higher than in the reference drug Armadin. Conclusions: 2,6-dimethylpyridine-N-oxide may be recommended for further detailed experimental studies as a perspective antihypoxant.

THE STUDY OF THE EFFECTIVENESS OF ANTIHYPOXIC PROPERTIES OF CERTAIN COMPOUNDS OF VARIOUS ACTION MECHANISMS ON HEMIC HYPOXIA MODELS

The article presents experimental data on the effectiveness of drugs that could stimulate the start of metabolic adaptation during the development of methemoglobinemia. The modeling of this type of hemic hypoxia led to the disruption of antioxidant protection, resulting in a rather significant decrease of superoxide dismutase and catalase (primary antioxidant enzymes) in the blood plasma of tested animals. We have established that anti-hypoxic activity was higher with the use of mexidol compared to the use of tocopherol. The differences in the indicators can perhaps be explained by the different mechanisms of action of the used antioxidants. The state of methemoglobinemia has also led to increased concentrations of medium-size molecules in the blood plasma. The use of mexidol and tocopherol did not show any significant effect on normalization.

Antihypoxic effect of new synthetic derivatives of 7-alkoxycoumarin and 4-aminocoumarin in acute hypobaric hypoxia in rats

BACKGROUND: Coumarins are naturally occurring molecules with a wide range of pharmacological activities. Their use is limited by difficulties in isolation from plant material, toxicity, and low solubility. The chemical structure of these compounds makes coumarins promising for the synthesis of a large number of derivatives that may have biological activity and be of interest as potential drugs. We had synthesized coumarin derivatives, two of which IEM-2266 (7-alkoxycoumarin derivative) and IEM-2267 (4-aminocoumarin derivative) have shown antihypoxic effect in mice in models of hypoxic hypoxia with hypercapnia, histotoxic and hemic hypoxia.
 AIM: The aim of this work was to study the antihypoxic effect of new coumarin derivatives IEM-2266 and IEM-2267 under conditions of acute hypobaric hypoxia in rats.
 METHODS: The experimental work was performed on male Wistar rats weighing 200220 g. Acute hypobaric hypoxia was induced in rats by placing them in a flow pressure chamber. Compounds IEM-2266 and IEM-2267 were administered intraperitoneally at the dose 25 mg/kg once 50 minutes before hypoxia. Mexidol at the dose of 100 mg/kg was used as a reference drug. The antihypoxic activity of the substances was assessed according to the following indicators: 1) lifespan at the critical height 11,000 m; 2) the value of the individual high-altitude threshold; 3) individual resistance to hypoxia calculated from high-altitude threshold, expressed in points; 4) survival at consistently presented heights; 5) determination of the structure of population resistance according to the ratio of animals with low, medium and high resistance to hypoxia.
 RESULTS: New coumarin derivatives IEM-2266 and IEM-2267 exhibited antihypoxic activity under acute hypobaric hypoxia conditions. With the use of IEM-2266, IEM-2267, and Mexidol, the lifespan of animals at a critical altitude of 11,000 m increased by 2.4, 5.4, and 4.9 times, respectively, compared with the control, the point based assessment of individual resistance to hypoxia increased by 36, 66 and 67%, the absolute value of high-altitude threshold increased significantly (p 0.05). Coumarin derivatives changed the structure of population resistance, increasing the proportion of highly resistant animals.
 CONCLUSIONS: Thus, the effect of IEM-2267 is comparable, and even exceeds the effect of Mexidol. The 7-alkoxycoumarin derivative IEM-2266 has a moderate, and the 4-aminocoumarin derivative IEM-2267 has high antihypoxic activity in rat AHbH conditions.

Effect of ethylthiobenzimidazole fumarate on the physical performance of mice under conditions of simultaneous hypoxic and hyperthermal exposure

The effect of ethylthiobenzimidazole fumarate (ETBIF) on physical performance with simultaneous exposure to hemic hypoxia and hyperthermia in the forced swim test was assessed. It was shown that ETBIF at a dose of 25 mg/kg increases the physical performance of male mice not only under the conditions of hypoxia or hyperthermia, but also under the combined effects of hypoxia and hyperthermia in a two-factor model.

Отравление селеном и его соединениями в промышленности и быту

Селен — химический элемент с атомным номером 34. Обозначается символом Se. Селен — необходимый для жизни микроэлемент. Обладает выраженными антиоксидантными и антиканцерогенными свойствами. Принимает участие во многих процессах в организме, чем обеспечивает функционирование иммунной и эндокринной систем. Влияет на физическое и умственное развитие у детей. Пища является основным источником селена для человека. В промышленности селен получают как побочный продукт переработки меди. Его используют в электронных полупроводниках, как обесцвечивающее вещество для керамики и стекла, как вулканизирующее вещество в производстве шин. Селен применяется в фармакологии, как антиканцерогенное средство. Соли селена легко всасываются слизистыми оболочками желудочно-кишечного тракта. В крови селен связывается с гемоглобином, образуется селенгемоглобин, в результате возникает гемическая гипоксия. В тканях селен вытесняет серу из серосодержащих аминокислот, нарушаются окислительно-восстановительные процессы. Селениты как активные антиоксиданты уменьшают активность глутатионпероксидазы и глутатионредуктазы и блокируют метаболизм глутатиона. Замена S-S связей селенотрисульфидными комплексами приводит к изменению третичной структуры белков и нарушает их функцию. В больших дозах селен вызывает отравление — селенизм. Для человека токсическая доза селена составляет 5 мг. Обладает политропным действием с преимущественным поражением печени, почек и центральной нервной системы. Острые тяжелые ингаляционные отравления протекают бурно и фульминантно. После вдыхания паров селена в больших концентрациях наблюдается потеря сознания и состояние коллапса. Характерным является чесночный запах изо рта. При ингаляционном пути поступления селена в концентрации 1–4 мкг/л описана клиника раздражения верхних дыхательных путей с развитием токсического отека легких и пневмонии. Наблюдаются явления гастроэнтерита, энцефаломиелита, анорексии, влажный и себорейный дерматит. Хроническая интоксикация селеном напоминает мышьяковую интоксикацию. Характерно снижение массы тела, апатия, усталость, мигрень, головокружение, тошнота, рвота, диарея, тяжесть в области правого подреберья, хронические бронхиты, гипохромная анемия; также выпадение волос, белые горизонтальные полосы на ногтях рук, паронихия, раздражительность, гиперрефлексия, чесночный запах при дыхании и металлический привкус во рту; болезненная чувствительность мышц, тремор, головокружение и покраснение лица. Лечение включает в себя введение антидотов, промывание слизистых оболочек, противошоковые мероприятия и симптоматическую терапию.

Острые отравления токсическими газами на производстве (лекция)

В лекции представлены ведущие механизмы поражения организма, типичная клиническая картина и принципы оказания экстренной медицинской помощи (ЭМП) и интенсивной терапии пострадавшим с острыми отравлениями токсическими газами. В связи с тем, что риск одновременного появления большого количества пострадавших с указанными отравлениями всегда велик именно в условиях химического производства, вопросы оказания ЭМП этому контингенту больных всегда актуальны. В лекции рассматриваются особенности поражения организма человека аммиаком, хлором, сероводородом, арсином, окислами азота, формальдегидом, монооксидом углерода и парами бензина. Все эти химические соединения являются широко распространенными химическими реагентами и промежуточными продуктами химических реакций на производстве. Ингаляционный путь попадания летучих веществ в организм определяет ускоренное развитие клинической симптоматики вследствие быстрого поступления токсичных химических соединений в кровь пострадавших. Расстройства в функционировании системы внешнего дыхания являются одними из наиболее распространенных при вдыхании таких агрессивных химических соединений, как аммиак, хлор, окислы азота, формальдегид, пары бензина. Поступление в организм угарного газа, окислов азота и сероводорода обусловливает высокий риск образования гемической гипоксии и связанных с ней поражений центральной нервной и сердечно-сосудистой системы. Вдыхание таких соединений, как сероводород, арсин, формальдегид, окись углерода, определяет развитие нарушений функционирования тканевого дыхания. Практически все химические соединения, действие которых представлено в лекции, способны оказывать общий токсический эффект на организм пострадавших. При освещении аспектов предоставления ЭМП подчеркивается потребность в немедленном прекращении контакта пациентов с токсическим веществом, профилактике и интенсивной терапии синдрома острой дыхательной недостаточности, применении антидотов и препаратов с противогипоксическим эффектом, которые улучшают процессы тканевого дыхания и способствуют росту выработки энергии.

Морфологические особенности клинических форм язвенного колита у детей

Актуальность. Язвенный колит (ЯК) — хроническое воспалительное заболевание неуточненного происхождения, характеризующееся клинически рецидивирующим течением с периодами кровавой диареи и патоморфологически — диффузным воспалительным процессом в толстой кишке. Проблема язвенного колита требует дальнейшего изучения клинических особенностей заболевания с учетом локализации, степени активности воспалительного процесса, изменений структуры слизистой оболочки, что будет способствовать повышению эффективности диагностики ЯК в детском возрасте. Материалы и методы. На основе клинико-статистического анализа 116 историй болезни детей с ЯК в возрасте 4–18 лет в периоде обострения болезни изучены особенности клинических форм ЯК — тотального, сегментарного и дистального. Гистологически было исследовано 445 биоптатов, полученных при колоноскопии. После забора материала биоптаты фиксировали в 10% формалине и обрабатывали по общепринятой гистологической методике с окраской срезов гематоксилин-эозином и по Ван Гизону. Результаты. В механизмах развития обострения ЯК существенное значение имеют изменения архитектоники слизистой оболочки толстой кишки, которые способствуют снижению резистентности слизистого барьера, а также нарушения кровоснабжения — фактор развития гемической гипоксии.