The circulatory system

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Cardiovascular System ◽  
Pulmonary Circulation ◽  
Circulatory System ◽  
Systemic Circulation ◽  
Vital Role ◽  
The Body ◽  
Two Systems ◽  
Thin Walled ◽  
Lower Loop ◽  
Muscular Pump

The circulatory system has two interrelated, but distinct parts, the cardiovascular system which circulates blood around the body and the lymphatic system which returns excess fluid from the tissues to the cardiovascular system. The function of the cardiovascular system is to oxygenate blood in the lungs and distribute the oxygenated blood to the tissues of the body. At the same time, carbon dioxide that accumulates as a result of metabolism of oxygen within the tissues is removed from the tissues and transported to the lungs where it is released from the blood and exhaled. The cardiovascular system comprises the heart, a muscular pump, and blood vessels. Arteries convey blood to thin-walled capillaries where gaseous exchange takes place and veins return blood to the heart. The cardiovascular system is often described as two parallel systems; the pulmonary circulation moves blood through the lungs and the systemic circulation circulates blood through the body. Trace the circulation of blood through the two systems in Figure 4.1 by following the arrows from the side of the heart coloured red. It follows a figure-of-eight (8) pattern with the two systems interlinked at the heart, the upper loop representing the pulmonary circulation and the lower loop the systemic circulation. The heart is a muscular pump driving blood at considerable pressure through arteries that get progressively smaller in both circulations until capillaries are reached. Arteries are sometimes dismissed as mere plumbing, but they play a vital role in regulating the blood flow through organs and tissues. Capillary walls are only one cell thick, allowing for the efficient diffusion of gases and small nutrient molecules to and from tissues. Waste gases and metabolites are also returned to the circulatory system through capillaries and these unite to form veins carrying blood under comparatively low pressure back to the heart. The heart comprises two muscular pumps arranged in parallel and beating in unison. As you can see in Figure 4.1, these two pumps are designated as the right and left sides of the heart. Each pump consists of two chambers, a thin-walled atrium that receives blood from one or other circulation and a thick-walled ventricle that ejects blood into the circulations.

scholarly journals The Mechanism of Secretion and Metabolism of Gut-Derived 5-Hydroxytryptamine

2021 ◽  
Vol 22 (15) ◽  
pp. 7931
Author(s):  
Ning Liu ◽  
Shiqiang Sun ◽  
Pengjie Wang ◽  
Yanan Sun ◽  
Qingjuan Hu ◽  
...  
Keyword(s):  
Cell Metabolism ◽  
Circulatory System ◽  
Vital Role ◽  
The Body ◽  
Neuroendocrine Cells ◽  
Intestinal Lumen ◽  
Paracrine Signaling ◽  
Inflammatory Conditions ◽  
Epithelial Development ◽  
Ec Cells

Serotonin, also known as 5-hydroxytryptamine (5-HT), is a metabolite of tryptophan and is reported to modulate the development and neurogenesis of the enteric nervous system, gut motility, secretion, inflammation, sensation, and epithelial development. Approximately 95% of 5-HT in the body is synthesized and secreted by enterochromaffin (EC) cells, the most common type of neuroendocrine cells in the gastrointestinal (GI) tract, through sensing signals from the intestinal lumen and the circulatory system. Gut microbiota, nutrients, and hormones are the main factors that play a vital role in regulating 5-HT secretion by EC cells. Apart from being an important neurotransmitter and a paracrine signaling molecule in the gut, gut-derived 5-HT was also shown to exert other biological functions (in autism and depression) far beyond the gut. Moreover, studies conducted on the regulation of 5-HT in the immune system demonstrated that 5-HT exerts anti-inflammatory and proinflammatory effects on the gut by binding to different receptors under intestinal inflammatory conditions. Understanding the regulatory mechanisms through which 5-HT participates in cell metabolism and physiology can provide potential therapeutic strategies for treating intestinal diseases. Herein, we review recent evidence to recapitulate the mechanisms of synthesis, secretion, regulation, and biofunction of 5-HT to improve the nutrition and health of humans.

scholarly journals Yogic Discipline in an individual human life

2021 ◽  
Vol 3 (4) ◽  
pp. 197-205
Author(s):  
Dharmalingam T.S ◽  
Balachandran P
Keyword(s):  
Human Life ◽  
Circulatory System ◽  
Vital Role ◽  
The Body ◽  
Self Control ◽  
Modern World ◽  
Breathing Exercise ◽  
Peace Of Mind ◽  
Self Confidence ◽  
Five Elements

In the modern world, the yoga plays a vital role in human life. To realise the truth and meaning of life, one has to practice yogic discipline in everyday living. The human body is made up of five elements such as akash, air, fire, water and earth. An air plays a very important role to survive by providing life energy. Everyday practice of pranayama would help in regulating respiratory system (Breathing exercise) as well as circulatory system. The physical exercises regulate the circulation of blood, heat, air in the body. The practice of asana would help in bringing flexibility in our muscular system so as to enhance the meditation process. The practice of meditation gives peace of mind and improves integirity. The practice of yoga will improve self-confidence, self-control, speaking truth, tolerance and social virtues. Each and every individual should practice yoga, asanas, meditation and do self-analysis exercises such as analysis of thoughts, moralisation of desires, nutralisation of anger and eradication of worries. This would help to bring hormoney between body and mind, habit and wisdom, self and society. Purpose and method and will and nature.

scholarly journals Comparative characteristics of changes in central hemodynamics during early recovery after different exercise regimes

2021 ◽  
Vol 27 (2) ◽  
pp. 47-52
Author(s):  
H.V. Lukyantseva ◽  
O.M. Bakunovsky ◽  
S.S. Malyuga ◽  
T.M. Oliinyk ◽  
N.R. Manchenko ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cardiovascular System ◽  
Dynamic Loading ◽  
Vascular Resistance ◽  
Dynamic Load ◽  
Static Loading ◽  
Circulatory System ◽  
The Body ◽  
Central Hemodynamics ◽  
Early Recovery

The cardiovascular system is one of the most important functional systems of the body, which determine the level of physical performance of the body. Insufficient study of the response of the circulatory system to the combination of strength training with endurance exercises requires more detailed comparative studies of the impact of dynamic and static loads on the indicators of central hemodynamics. Accordingly, the aim of our study was to study the characteristics of the reaction of the cardiovascular system in the period of early recovery after dosed exercise of a dynamic and static nature. The study examined the response of the central hemodynamics of young men in the period of early recovery after dynamic loading (Martine functional test) and static loading (holding on the stand dynamometer DS-200 force with a power of 50% of maximum standing force). The change in circulatory system parameters was recorded using a tetrapolar thoracic impedance rheoplethysmogram on a computerized diagnostic complex “Cardio +”. It is established that the dynamic load in the period of early recovery does not cause a significant positive chronotropic effect, leads to a decrease in vascular resistance of blood flow, to an increase in pulse blood pressure. The increase in cardiac output is mainly due to the increase in stroke volume, which indicates a fairly high functional reserves of the heart. It is revealed that under conditions of static loading the reaction of central hemodynamics and the course of early recovery are radically different from the changes of indicators under dynamic loading. In persons with a normodynamic type of reaction to dynamic load, there are no significant changes in the minute volume of blood at a similar volume of active muscle mass static load. Meeting the metabolic needs of working skeletal muscles and compensating for the oxygen debt is realized by increasing the total peripheral vascular resistance and increasing systolic blood pressure in the postpartum period. The physiological meaning of this phenomenon is to maintain a sufficient level of venous return of blood to ensure the pumping function of the heart.

Effect of high intra-alveolar O2 tensions on pulmonary circulation in perfused lungs of dogs

1965 ◽  
Vol 208 (1) ◽  
pp. 130-138 ◽  
Author(s):  
G. J. A. Cropp
Keyword(s):  
Blood Flow ◽  
Pulmonary Vascular Resistance ◽  
Vascular Resistance ◽  
Pulmonary Circulation ◽  
Time Course ◽  
Systemic Circulation ◽  
The Body ◽  
Arterial Blood ◽  
Pulmonary Parenchyma ◽  
Pulmonary Arterial

The resistance to blood flow in the pulmonary circulation of dogs (PVR) increased when their lungs were ventilated with 95–100% oxygen and were perfused with blood that recirculated only through the pulmonary circulation; the systemic circulation was perfused independently. This increase in PVR occurred even when nerves were cut or blocked but was abolished by inhaled isopropylarterenol aerosol. Elevation of intra-alveolar Po2 without increase in pulmonary arterial blood Po2 was sufficient to increase pulmonary vascular resistance. The pulmonary venules or veins were thought to be the likely site of the constriction. These reactions were qualitatively similar to those produced by injection of serotonin or histamine into the pulmonary circulation. The time course of the response and failure to obtain it when the blood was perfused through the remainder of the body before it re-entered the pulmonary circulation are compatible with a theory that high intra-alveolar O2 tension activates a vasoconstrictor material in the pulmonary parenchyma.

scholarly journals Towards enabling a cardiovascular digital twin for human systemic circulation using inverse analysis

2020 ◽  
Author(s):  
Neeraj Kavan Chakshu ◽  
Igor Sazonov ◽  
Perumal Nithiarasu
Keyword(s):  
Cardiovascular System ◽  
Inverse Analysis ◽  
Short Term Memory ◽  
Systemic Circulation ◽  
The Body ◽  
Digital Twin ◽  
Patient Database ◽  
Health Care Infrastructure ◽  
Analysis System ◽  
High Degree

Abstract An exponential rise in patient data provides an excellent opportunity to improve the existing health care infrastructure. In the present work, a method to enable cardiovascular digital twin is proposed using inverse analysis. Conventionally, accurate analytical solutions for inverse analysis in linear problems have been proposed and used. However, these methods fail or are not efficient for nonlinear systems, such as blood flow in the cardiovascular system (systemic circulation) that involves high degree of nonlinearity. To address this, a methodology for inverse analysis using recurrent neural network for the cardiovascular system is proposed in this work, using a virtual patient database. Blood pressure waveforms in various vessels of the body are inversely calculated with the help of long short-term memory (LSTM) cells by inputting pressure waveforms from three non-invasively accessible blood vessels (carotid, femoral and brachial arteries). The inverse analysis system built this way is applied to the detection of abdominal aortic aneurysm (AAA) and its severity using neural networks.

Analysis of Central Hemodynamic Parameters in Medical Students during the Pre-Examination Study Period

2021 ◽  
pp. 67-73
Author(s):  
VA Belyayeva
Keyword(s):  
Body Mass Index ◽  
Heart Rate ◽  
Medical Students ◽  
Cardiovascular System ◽  
Body Mass ◽  
Circulatory System ◽  
The Body ◽  
Hemodynamic Parameters ◽  
Adaptive Potential ◽  
Central Hemodynamic

Background: One of the main negative factors of the educational environment is the increased stress impact on the cardiovascular system of students preparing for examinations. The cumulative effect of a long-term, systematic exposure to stressors may be accompanied by impaired mental and somatic health of students. The extent of response to stress is individual; it is usually determined by cardiovascular health and a complex of psychophysiological characteristics of the body. Objective: To study the main parameters of central hemodynamics in medical students depending on the body mass index and adaptive potential in the pre-examination study period Materials and methods: In spring–summer 2019, 170 medical students (young men and women aged 20.4 ± 0.3 years) with different adaptive potential of the circulatory system were surveyed during a pre-exam study period to establish their anthropometric indicators, blood pressure and heart rate and to further estimate the body mass index and the main central hemodynamics parameters. Results: The average heart rate of students during the pre-exam study period was 85.4 ± 12.21 beats per minute. The level of metabolic and energy processes in the myocardium was characterized as moderate with a tendency to insufficient functional capacity of the cardiovascular system (CI = 90.4 ± 1.22). Significant differences were revealed in a number of parameters un-der study depending on gender, body mass index (F = 3.99; p = 0.00890) and the adaptive potential of the circulatory system (F = 23.08; p = 0.00000). Conclusions: In the pre-examination study period, both the heart rate and the Kerdo index among the students were elevated, which indicates the predominance of sympathetic autonomic stress. The students with tense adaptation mechanisms demonstrated higher values of certain hemodynamic parameters. The pulse pressure and the Robinson index were higher in overweight students compared to their peers with a normal body mass index. None of the students with class 1 obesity had a satisfactory level of adaptation of the circulatory system. The analysis of central hemodynamic parameters enables the assessment of tolerance of the cardiovascular system of students to the burden of learning.

DIAGNOSIS OF PSYCHO-EMOTIONAL STRESS IN PROFESSIONAL RECRUITMENT

2021 ◽  
Author(s):  
O.V. Zhbankova ◽  
◽  
O.I. Yushkova ◽  
A.V. Kapustina
Keyword(s):  
Cardiovascular System ◽  
Acute Stress ◽  
Dynamic Pressure ◽  
Peripheral Resistance ◽  
Circulatory System ◽  
Minute Volume ◽  
The Body ◽  
Psychological Status ◽  
Psychomotor Skills ◽  
Resistance To Stress

Abstract. Introduction. Professional selection of workers in extreme occupations associated with increased danger and responsibility is an important task of labor physiology. The study of psychomotor skills under conditions of acute stress, the assessment of the physiological reactions of the cardiovascular system will determine the professional suitability of candidates for various specialties (technical or intellectual-analytical). Purpose of work. The study of diagnostic methodological approaches to assessing the professional suitability of persons in hazardous professions in psychophysiological professional selection. Materials and methods. Psychophysiological studies included the study of psychomotor skills, psychological testing according to the MMIL and 16 FLO tests, physiological studies of hemodynamic features in candidates with different resistance to stress (calculation of stroke blood volume - SV, MC blood minute volume and peripheral resistance of PS), professional analysis of the labor activity of workers to identify the requirements that hazardous professions place on the body of workers, Research results. In candidates for engineering and technical specialties, the tension of the circulatory system reflected high values of the average dynamic pressure (105.73 ± 1.45 mm Hg), changes in the optimal hyperkinetic type of blood circulation to hypokinetic: 66.7% of those examined with low resistance to stress. In candidates for communicative specialties, a sufficient level of physical activity contributed to the stability of the indicators of the cardiovascular system. Conclusions. Informative indicators have been established for assessing the professional suitability of candidates to perform official tasks in extreme conditions: changes in handwriting signs, peculiarities of psychological status (anxiety, conformism), hemodynamic characteristics

The circulatory system

2020 ◽  
Vol 14 (11) ◽  
pp. 548-553
Author(s):  
Ian Peate
Keyword(s):  
Cardiovascular System ◽  
Circulatory System ◽  
The Body ◽  
Body System ◽  
Effective Care ◽  
Other Substances

The circulatory system transports blood around the body. The blood carries a number of other substances needed by the body to function effectively; the cardiovascular system keeps life pumping through the body. This article offers an overview of this essential body system. It is vital to understanding the various functions of the cardiovascular system, along with its various pathways of veins, arteries and capillaries when providing people with safe and effective care. A glossary of terms has been included. A short quiz at the end of the article has been provided to encourage recall and learning.

Physiologically assessing the functional state of the body of doctors in children's medical organizations

2020 ◽  
Vol 60 (11) ◽  
pp. 775-777
Author(s):  
Anna V. Zayitceva ◽  
Khistina T. Oniani
Keyword(s):  
Cardiovascular System ◽  
Shift Work ◽  
Functional State ◽  
Night Shift ◽  
Circulatory System ◽  
Holter Monitoring ◽  
The Body ◽  
Pronounced Increase ◽  
Functional Capabilities ◽  
Shift Work Schedule

Introduction. Increased nervous and emotional loads in doctors of children's medical organizations are caused by frequent stressful effects, shift work mode. The study of the features of the formation of the functional state of the body of surgeons will make it possible to scientifically justify measures to prevent overstrain to preserve the health of employees. The aim of study is to research the functional state of the body of doctors of children's medical organizations with a shift work schedule to justify and develop measures for physiological and hygienic optimization of work. Materials and methods. Complex physiological and hygienic studies included occupational analysis of labor activity, physiological studies of the state of the Central nervous system (CNS) and the cardiovascular system with the study of the features of response to functional loads (ECG recording on a 12-channel electrocardiograph and continuously using Holter monitoring). Results. The study of the features and degree of adequacy of the cardiovascular system's response to dosed physical activity revealed the tension of the regulatory mechanisms of the circulatory system with a pronounced increase in heart activity in surgeons during night hours. Conclusions. Stable indicators of CNS functions (concentration of attention, etc.) were established during various shifts, due to the requirements of the work itself, adverse changes in the cardiovascular system, more pronounced during the night shift, deterioration of ECG changes to functional load, which indicates a decrease in the functional capabilities of the myocardium.

scholarly journals Diagnostic and Therapeutic Potential of Extracellular Vesicles

2021 ◽  
Vol 20 ◽  
pp. 153303382110412
Author(s):  
Sai Priyanka Kodam ◽  
Mujib Ullah
Keyword(s):  
Extracellular Vesicles ◽  
Therapeutic Potential ◽  
Drug Carriers ◽  
Systemic Circulation ◽  
Vital Role ◽  
The Body ◽  
Biological Molecules ◽  
Diagnostic Tools ◽  
Target Organs ◽  
And Storage

Extracellular vesicles (EVs) are naturally phospholipid enclosed nanovesicles released by many cells in the body. They are stable in circulation, have low immunogenicity, and act as carriers for functionally active biological molecules. They interact with target organs and bind to the receptors. Their target specificity is important to use EVs as noninvasive diagnostic and prognostic tools. EVs play a vital role in normal physiology and cellular communication. They are known to protect their cargo from degradation, which makes them important drug carriers for targeted drug delivery. Using EVs with markers and tracking their path in systemic circulation can be revolutionary in using them as diagnostic tools. We will discuss the scope of this in this paper. Although there are limitations in EVs isolation and storage, their high biocompatibility will fuel more innovations to overcome these challenges.

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