Science.gov

Sample records for human circulatory system

  1. Representations of the Human Circulatory System

    ERIC Educational Resources Information Center

    Lopez-Manjon, Asuncion; Angon, Yolanda Postigo

    2009-01-01

    There is no agreement about the robustness of intuitive representations of the circulatory system and their susceptibility to change by instruction. In this paper, we analyse to what extent students with varying degrees of biology instruction and different ages (High School Health Science and Social Science students and first and final year…

  2. Representations of the Human Circulatory System

    ERIC Educational Resources Information Center

    Lopez-Manjon, Asuncion; Angon, Yolanda Postigo

    2009-01-01

    There is no agreement about the robustness of intuitive representations of the circulatory system and their susceptibility to change by instruction. In this paper, we analyse to what extent students with varying degrees of biology instruction and different ages (High School Health Science and Social Science students and first and final year…

  3. Simulation of a human circulatory system.

    PubMed

    Menon, Vinay

    2012-01-01

    This article describes a mathematically based human circulatory model. The model consists of lumped elements made of venous, arterial, peripheral, pulmonary vein and artery segments. A heart model is simulated using 4 chambers (left and right atriums and ventricles). The heart pump mechanism is operated by a simple piston based models for each of the chambers. The simulation consists of 19 (states) first order differential equations. and simulated with Matlab and Simulink. The simulation computes volume, flow rate and pressures in each segment.

  4. An Integrated Simulation Tool for Modeling the Human Circulatory System

    NASA Astrophysics Data System (ADS)

    Asami, Ken'ichi; Kitamura, Tadashi

    This paper presents an integrated simulation of the circulatory system in physiological movement. The large circulatory system model includes principal organs and functional units in modules in which comprehensive physiological changes such as nerve reflexes, temperature regulation, acid/base balance, O2/CO2 balance, and exercise are simulated. A beat-by-beat heart model, in which the corresponding electrical circuit problems are solved by a numerical analytic method, enables calculation of pulsatile blood flow to the major organs. The integration of different perspectives on physiological changes makes this simulation model applicable for the microscopic evaluation of blood flow under various conditions in the human body.

  5. Towards a Fast Dynamic Model of the Human Circulatory System

    DTIC Science & Technology

    2011-10-06

    4.5m for the pulmonary vascular tree. According to Guyton & Hall (2000), about 5 L is considered normal for an adult human, and the area distribution...decreases further, and even falls below the equilibrium pressure. Guyton & Hall (2000) reports that normal mean pressures are 100 mmHg in the arteries, 20...the order of 100 times faster than realtime. Five liters is considered a normal volume for an adult human circulatory system ( Guyton & Hall, 2000

  6. Towards a Fast Dynamic Model of the Human Circulatory System

    NASA Astrophysics Data System (ADS)

    Kaplan, Carolyn; Green, Melissa; Boris, Jay; Oran, Elaine

    2011-11-01

    We describe a model for systems-level transport in the human circulatory system that is based on a set of equations for a one-dimensional unsteady elastic pipe flow circuit. The system is collapsed from three spatial dimensions and time to one spatial dimension and time by assuming axisymmetric vessel geometry and a parabolic velocity profile across the cylindrical vessels. To drive the fluid, the contractions of a beating heart are modeled as periodic area changes of the elastic vessels. Two different models are compared, both including and neglecting fluid acceleration. Time-resolved distributions of pressure, velocity and area compare reasonably well with reference data. Increasing the rigidity of the vasculature is found to increase peak arterial pressures on the order of ten percent, and including a distributed vascular contraction to model distributed skeletal muscle contractions monotonically increases time-averaged blood flow in the veins, consistent with human physiological response. The circulatory system model presented here simulates the circulatory system on the order of one hundred times faster than real-time; that is, we can compute thousands of heartbeats per minute of CPU time.

  7. A Simulink model for the human circulatory system.

    PubMed

    Wabel, P; Leonhardt, S

    1998-01-01

    This paper presents the mathematical simulation of the human circulatory system. The model is based on the former work of Coleman and co-workers and has been redesigned for simulation with the Matlab toolbox "Simulink". It includes the heart and the peripheral circulation, the respiratory system, the kidneys and the major neural and hormonal control mechanisms, which are necessary for maintaining homeostasis. The model contains more than 30 blocks with over 200 physiological variables, which can be accessed and plotted during the simulation.

  8. Computational Hemodynamic Simulation of Human Circulatory System under Altered Gravity

    NASA Technical Reports Server (NTRS)

    Kim. Chang Sung; Kiris, Cetin; Kwak, Dochan

    2003-01-01

    A computational hemodynamics approach is presented to simulate the blood flow through the human circulatory system under altered gravity conditions. Numerical techniques relevant to hemodynamics issues are introduced to non-Newtonian modeling for flow characteristics governed by red blood cells, distensible wall motion due to the heart pulse, and capillary bed modeling for outflow boundary conditions. Gravitational body force terms are added to the Navier-Stokes equations to study the effects of gravity on internal flows. Six-type gravity benchmark problems are originally presented to provide the fundamental understanding of gravitational effects on the human circulatory system. For code validation, computed results are compared with steady and unsteady experimental data for non-Newtonian flows in a carotid bifurcation model and a curved circular tube, respectively. This computational approach is then applied to the blood circulation in the human brain as a target problem. A three-dimensional, idealized Circle of Willis configuration is developed with minor arteries truncated based on anatomical data. Demonstrated is not only the mechanism of the collateral circulation but also the effects of gravity on the distensible wall motion and resultant flow patterns.

  9. Development of a mathematical model of the human circulatory system.

    PubMed

    Conlon, Martin J; Russell, Donald L; Mussivand, Tofy

    2006-09-01

    A mathematical lumped parameter model of the human circulatory system (HCS) has been developed to complement in vitro testing of ventricular assist devices. Components included in this model represent the major parts of the systemic HCS loop, with all component parameters based on physiological data available in the literature. Two model configurations are presented in this paper, the first featuring elements with purely linear constitutive relations, and the second featuring nonlinear constitutive relations for the larger vessels. Three different aortic compliance functions are presented, and a pressure-dependent venous flow resistance is used to simulate venous collapse. The mathematical model produces reasonable systemic pressure and flow behaviour, and graphs of this data are included.

  10. Mathematical circulatory system model

    NASA Technical Reports Server (NTRS)

    Lakin, William D. (Inventor); Stevens, Scott A. (Inventor)

    2010-01-01

    A system and method of modeling a circulatory system including a regulatory mechanism parameter. In one embodiment, a regulatory mechanism parameter in a lumped parameter model is represented as a logistic function. In another embodiment, the circulatory system model includes a compliant vessel, the model having a parameter representing a change in pressure due to contraction of smooth muscles of a wall of the vessel.

  11. Facilitating Conceptual Change in Ninth Grade Students' Understanding of Human Circulatory System Concepts

    ERIC Educational Resources Information Center

    Alkhawaldeh, Salem A.

    2007-01-01

    The purpose of this study was to investigate the effectiveness of the conceptual change text oriented instruction over traditionally designed instruction on ninth grade students' understanding of the human circulatory system concepts, and their retention of this understanding. The subjects of this study consist of 73 ninth grade female students…

  12. Students' Alternative Conceptions of the Human Circulatory System: A Cross-Age Study.

    ERIC Educational Resources Information Center

    Arnaudin, Mary W.; Mintzes, Joel J.

    1985-01-01

    Concept maps and structured/clinical interviews were completed by 25 fourth graders and 25 college freshmen to determine knowledge of the human circulatory system. Students (N=945) at various levels were then measured for misconception frequencies. Student preconceptions appear to be tenacious, but confrontation strategies may assist fundamental…

  13. Students' Achievement in Human Circulatory System Unit: The Effect of Reasoning Ability and Gender.

    ERIC Educational Resources Information Center

    Sungur, Semra; Tekkaya, Ceren

    2003-01-01

    Investigates the effect of gender and reasoning ability on the human circulatory system concepts achievement and attitude toward biology. Reports a statistically significant mean difference between concrete and formal students with regard to achievement and attitude toward biology. (Contains 24 references.) (Author/YDS)

  14. Facilitating Conceptual Change in Ninth Grade Students' Understanding of Human Circulatory System Concepts

    ERIC Educational Resources Information Center

    Alkhawaldeh, Salem A.

    2007-01-01

    The purpose of this study was to investigate the effectiveness of the conceptual change text oriented instruction over traditionally designed instruction on ninth grade students' understanding of the human circulatory system concepts, and their retention of this understanding. The subjects of this study consist of 73 ninth grade female students…

  15. Learning in a Non-Physical Science Domain: The Human Circulatory System.

    ERIC Educational Resources Information Center

    Chi, Michelene T. H.; And Others

    This research explores the moment-by-moment understanding students exhibit in the learning of a non-physical science domain--the human circulatory system. The goal was to understand how students learn by capturing the nature of their initial mental models (naive conceptions), and by seeing how new information gets assimilated into their mental…

  16. The Persistence of Misconceptions about the Human Blood Circulatory System among Students in Different Grade Levels

    ERIC Educational Resources Information Center

    Ozgur, Sami

    2013-01-01

    In this paper, it is aimed to investigate the persistence of misconceptions in the topic of the human blood circulatory system among students in different grade levels. For this reason, after discussions with biology educators, two tests consisting of open-ended questions were developed by the researcher and administered to students in four…

  17. Students' Achievement in Human Circulatory System Unit: The Effect of Reasoning Ability and Gender.

    ERIC Educational Resources Information Center

    Sungur, Semra; Tekkaya, Ceren

    2003-01-01

    Investigates the effect of gender and reasoning ability on the human circulatory system concepts achievement and attitude toward biology. Reports a statistically significant mean difference between concrete and formal students with regard to achievement and attitude toward biology. (Contains 24 references.) (Author/YDS)

  18. Students' Alternative Conceptions of the Human Circulatory System: A Cross-Age Study.

    ERIC Educational Resources Information Center

    Arnaudin, Mary W.; Mintzes, Joel J.

    1985-01-01

    Concept maps and structured/clinical interviews were completed by 25 fourth graders and 25 college freshmen to determine knowledge of the human circulatory system. Students (N=945) at various levels were then measured for misconception frequencies. Student preconceptions appear to be tenacious, but confrontation strategies may assist fundamental…

  19. Developing seventh grade students' systems thinking skills in the context of the human circulatory system.

    PubMed

    Raved, Lena; Yarden, Anat

    2014-01-01

    Developing systems thinking skills in school can provide useful tools to deal with a vast amount of medical and health information that may help learners in decision making in their future lives as citizen. Thus, there is a need to develop effective tools that will allow learners to analyze biological systems and organize their knowledge. Here, we examine junior high school students' systems thinking skills in the context of the human circulatory system. A model was formulated for developing teaching and learning materials and for characterizing students' systems thinking skills. Specifically, we asked whether seventh grade students, who studied about the human circulatory system, acquired systems thinking skills, and what are the characteristics of those skills? Concept maps were used to characterize students' systems thinking components and examine possible changes in the students' knowledge structure. These maps were composed by the students before and following the learning process. The study findings indicate a significant improvement in the students' ability to recognize the system components and the processes that occur within the system, as well as the relationships between different levels of organization of the system, following the learning process. Thus, following learning students were able to organize the systems' components and its processes within a framework of relationships, namely the students' systems thinking skills were improved in the course of learning using the teaching and learning materials.

  20. Developing Seventh Grade Students’ Systems Thinking Skills in the Context of the Human Circulatory System

    PubMed Central

    Raved, Lena; Yarden, Anat

    2014-01-01

    Developing systems thinking skills in school can provide useful tools to deal with a vast amount of medical and health information that may help learners in decision making in their future lives as citizen. Thus, there is a need to develop effective tools that will allow learners to analyze biological systems and organize their knowledge. Here, we examine junior high school students’ systems thinking skills in the context of the human circulatory system. A model was formulated for developing teaching and learning materials and for characterizing students’ systems thinking skills. Specifically, we asked whether seventh grade students, who studied about the human circulatory system, acquired systems thinking skills, and what are the characteristics of those skills? Concept maps were used to characterize students’ systems thinking components and examine possible changes in the students’ knowledge structure. These maps were composed by the students before and following the learning process. The study findings indicate a significant improvement in the students’ ability to recognize the system components and the processes that occur within the system, as well as the relationships between different levels of organization of the system, following the learning process. Thus, following learning students were able to organize the systems’ components and its processes within a framework of relationships, namely the students’ systems thinking skills were improved in the course of learning using the teaching and learning materials. PMID:25520948

  1. [Essence of meridians and collaterals: circulatory conduction system of bio-electricity of human].

    PubMed

    Shang, Zhen-De

    2011-03-01

    The running courses of twelve meridians are explained through the electrical properties of cell membrane, and the phenomenon related with meridians such as mechanism of acupuncture analgesia and acupuncture anesthesia, pause of the propagated sensation along channels, nature of propagated sensation and width of propagated sensation is expounded in this article. As a result, it is held that the meridian system, a circulatory conduction system of bio-electricity of human, is an independent system from the known nine large systems.

  2. Numerical Models of Human Circulatory System under Altered Gravity: Brain Circulation

    NASA Technical Reports Server (NTRS)

    Kim, Chang Sung; Kiris, Cetin; Kwak, Dochan; David, Tim

    2003-01-01

    A computational fluid dynamics (CFD) approach is presented to model the blood flow through the human circulatory system under altered gravity conditions. Models required for CFD simulation relevant to major hemodynamic issues are introduced such as non-Newtonian flow models governed by red blood cells, a model for arterial wall motion due to fluid-wall interactions, a vascular bed model for outflow boundary conditions, and a model for auto-regulation mechanism. The three-dimensional unsteady incompressible Navier-Stokes equations coupled with these models are solved iteratively using the pseudocompressibility method and dual time stepping. Moving wall boundary conditions from the first-order fluid-wall interaction model are used to study the influence of arterial wall distensibility on flow patterns and wall shear stresses during the heart pulse. A vascular bed modeling utilizing the analogy with electric circuits is coupled with an auto-regulation algorithm for multiple outflow boundaries. For the treatment of complex geometry, a chimera overset grid technique is adopted to obtain connectivity between arterial branches. For code validation, computed results are compared with experimental data for steady and unsteady non-Newtonian flows. Good agreement is obtained for both cases. In sin-type Gravity Benchmark Problems, gravity source terms are added to the Navier-Stokes equations to study the effect of gravitational variation on the human circulatory system. This computational approach is then applied to localized blood flows through a realistic carotid bifurcation and two Circle of Willis models, one using an idealized geometry and the other model using an anatomical data set. A three- dimensional anatomical Circle of Willis configuration is reconstructed from human-specific magnetic resonance images using an image segmentation method. The blood flow through these Circle of Willis models is simulated to provide means for studying gravitational effects on the brain

  3. Development and Validation of a Two-Tier Instrument to Examine Understanding of Internal Transport in Plants and the Human Circulatory System

    ERIC Educational Resources Information Center

    Wang, Jing-Ru

    2004-01-01

    This study is intended to develop an assessment instrument to investigate students' understandings about internal transport in plants and human circulatory system. A refined process of a two-tier diagnostic test was used to develop the instrument. Finally, three versions of the Internal Transport in Plants and the Human Circulatory System test…

  4. Development and Validation of a Two-Tier Instrument to Examine Understanding of Internal Transport in Plants and the Human Circulatory System

    ERIC Educational Resources Information Center

    Wang, Jing-Ru

    2004-01-01

    This study is intended to develop an assessment instrument to investigate students' understandings about internal transport in plants and human circulatory system. A refined process of a two-tier diagnostic test was used to develop the instrument. Finally, three versions of the Internal Transport in Plants and the Human Circulatory System test…

  5. Students' Visualization of Diagrams Representing the Human Circulatory System: The Use of Spatial Isomorphism and Representational Conventions

    ERIC Educational Resources Information Center

    Cheng, Maurice M. W.; Gilbert, John K.

    2015-01-01

    This study investigated students' interpretation of diagrams representing the human circulatory system. We conducted an interview study with three students aged 14-15 (Year 10) who were studying biology in a Hong Kong school. During the interviews, students were asked to interpret diagrams and relationships between diagrams that represented…

  6. The Contribution of Conceptual Change Texts Accompanied by Concept Mapping to Students' Understanding of the Human Circulatory System.

    ERIC Educational Resources Information Center

    Sungur, Semra; Tekkaya, Ceren; Geban, Omer

    2001-01-01

    Investigates the contribution of conceptual change texts accompanied by concept mapping instruction to 10th-grade students' understanding of the human circulatory system. Indicates that the conceptual change texts accompanied by concept mapping instruction produced a positive effect on students' understanding of concepts. Concludes that students…

  7. Students' Visualization of Diagrams Representing the Human Circulatory System: The Use of Spatial Isomorphism and Representational Conventions

    ERIC Educational Resources Information Center

    Cheng, Maurice M. W.; Gilbert, John K.

    2015-01-01

    This study investigated students' interpretation of diagrams representing the human circulatory system. We conducted an interview study with three students aged 14-15 (Year 10) who were studying biology in a Hong Kong school. During the interviews, students were asked to interpret diagrams and relationships between diagrams that represented…

  8. The Contribution of Conceptual Change Texts Accompanied by Concept Mapping to Students' Understanding of the Human Circulatory System.

    ERIC Educational Resources Information Center

    Sungur, Semra; Tekkaya, Ceren; Geban, Omer

    2001-01-01

    Investigates the contribution of conceptual change texts accompanied by concept mapping instruction to 10th-grade students' understanding of the human circulatory system. Indicates that the conceptual change texts accompanied by concept mapping instruction produced a positive effect on students' understanding of concepts. Concludes that students…

  9. Relations of Cognitive and Motivational Variables with Students' Human Circulatory System Achievement in Traditional and Learning Cycle Classrooms

    ERIC Educational Resources Information Center

    Sadi, Özlem; Çakiroglu, Jale

    2014-01-01

    This study is aimed at investigating the relationships among students' relevant prior knowledge, meaningful learning orientation, reasoning ability, self-efficacy, locus of control, attitudes toward biology and achievement with the human circulatory system (HCS) using the learning cycle (LC) and the traditional classroom setting. The study was…

  10. Photoacoustic detection of metastatic melanoma cells in the human circulatory system.

    PubMed

    Weight, Ryan M; Viator, John A; Dale, Paul S; Caldwell, Charles W; Lisle, Allison E

    2006-10-15

    Detection of disseminating tumor cells among patients suffering from various types and stages of cancer can function as an early warning system, alerting the physician of the metastatic spread or recurrence of the disease. Early detection of such cells can result in preventative treatment of the disease, while late stage detection can serve as an indicator of the effectiveness of chemotherapeutics. The prognostic value of exposing disseminating tumor cells poses an urgent need for an efficient, accurate screening method for metastatic cells. We propose a system for the detection of metastatic circulating tumor cells based on the thermoelastic properties of melanoma. The method employs photoacoustic excitation coupled with a detection system capable of determining the presence of disseminating cells within the circulatory system in vitro. Detection trials consisting of tissue phantoms and a human melanoma cell line resulted in a detection threshold of the order of ten individual cells, thus validating the effectiveness of the proposed mechanism. Results imply the potential to assay simple blood draws, from healthy and metastatic patients, for the presence of cancerous melanoma providing an unprecedented method for routine cancer screening.

  11. Photoacoustic detection of metastatic melanoma cells in the human circulatory system

    NASA Astrophysics Data System (ADS)

    Weight, Ryan M.; Viator, John A.; Dale, Paul S.; Caldwell, Charles W.; Lisle, Allison E.

    2006-10-01

    Detection of disseminating tumor cells among patients suffering from various types and stages of cancer can function as an early warning system, alerting the physician of the metastatic spread or recurrence of the disease. Early detection of such cells can result in preventative treatment of the disease, while late stage detection can serve as an indicator of the effectiveness of chemotherapeutics. The prognostic value of exposing disseminating tumor cells poses an urgent need for an efficient, accurate screening method for metastatic cells. We propose a system for the detection of metastatic circulating tumor cells based on the thermoelastic properties of melanoma. The method employs photoacoustic excitation coupled with a detection system capable of determining the presence of disseminating cells within the circulatory system in vitro. Detection trials consisting of tissue phantoms and a human melanoma cell line resulted in a detection threshold of the order of ten individual cells, thus validating the effectiveness of the proposed mechanism. Results imply the potential to assay simple blood draws, from healthy and metastatic patients, for the presence of cancerous melanoma providing an unprecedented method for routine cancer screening.

  12. Students' Visualization of Diagrams Representing the Human Circulatory System: The use of spatial isomorphism and representational conventions

    NASA Astrophysics Data System (ADS)

    Cheng, Maurice M. W.; Gilbert, John K.

    2015-01-01

    This study investigated students' interpretation of diagrams representing the human circulatory system. We conducted an interview study with three students aged 14-15 (Year 10) who were studying biology in a Hong Kong school. During the interviews, students were asked to interpret diagrams and relationships between diagrams that represented aspects of the circulatory system. All diagrams used in the interviews had been used by their teacher when teaching the topic. Students' interpretations were expressed by their verbal response and their drawing. Dual coding theory was used to interpret students' responses. There was evidence that one student relied on verbal recall as a strategy in interpreting diagrams. It was found that students might have relied unduly on similarities in spatial features, rather than on deeper meanings represented by conventions, of diagrams when they associated diagrams that represented different aspects of the circulatory system. A pattern of students' understanding of structure-behaviour-function relationship of the biological system was observed. This study suggests the importance of a consistent diagrammatic and verbal representation in communicating scientific ideas. Implications for teaching practice that facilitates learning with diagrams and address students' undue focus on spatial features of diagrams are discussed.

  13. [Circulatory disease surveillance system in Korea].

    PubMed

    Chun, Byung-Yeol

    2007-07-01

    The purpose of establishing the circulatory disease surveillance system in Korea is to ensure that the problems of circulatory disease importance are being monitored efficiently and effectively. The goals of circulatory disease surveillance system are to monitor the epidemiological trends of circulatory disease and to evaluate the outcome of health activity for controlling circulatory diseases. Surveillance system are being updated to achieve the needs for the integration of the surveillance and information system, the establishment of data standards, the electronic exchange of data, and changes in the goals of circulatory disease surveillance system to facilitate the response of this system to manage the national health problem effectively. This article provides the target diseases and determinant indicators to be monitored, structure of circulatory disease surveillance system, and many tasks and related activities that should be applied to this system.

  14. The human heart and the circulatory system as an interesting interdisciplinary topic in lessons of physics and biology

    NASA Astrophysics Data System (ADS)

    Volná, M.; Látal, F.; Kubínek, R.; Richterek, L.

    2014-01-01

    Many topics which are closely related can be found in the national curriculum of the Czech Republic for physics and biology. One of them is the heart and the circulatory system in the human body. This topic was examined cross curriculum, a teaching module was created and the topic was chosen for our research. The task was to determine if the students of bachelor study are aware of connections between physics and biology within this topic and whether we can help them effectively to describe the corresponding physics phenomena in the human body connected, for example, with a heart attack or with the measurement of blood pressure. In this paper, the heart and the circulatory system are presented as suitable topics for an interdisciplinary teaching module which includes both theoretical and experimental parts. The module was evaluated by a group of first-year undergraduate students of physics at the Faculty of Science, Palacký University. The acquired knowledge was compared with another control group through a test. The highest efficiency of the module was evaluated on the basis of questions that covered the calculation problems.

  15. Progression of Mortality due to Diseases of the Circulatory System and Human Development Index in Rio de Janeiro Municipalities.

    PubMed

    Soares, Gabriel Porto; Klein, Carlos Henrique; Silva, Nelson Albuquerque de Souza E; Oliveira, Glaucia Maria Moraes de

    2016-10-01

    Diseases of the circulatory system (DCS) are the major cause of death in Brazil and worldwide. To correlate the compensated and adjusted mortality rates due to DCS in the Rio de Janeiro State municipalities between 1979 and 2010 with the Human Development Index (HDI) from 1970 onwards. Population and death data were obtained in DATASUS/MS database. Mortality rates due to ischemic heart diseases (IHD), cerebrovascular diseases (CBVD) and DCS adjusted by using the direct method and compensated for ill-defined causes. The HDI data were obtained at the Brazilian Institute of Applied Research in Economics. The mortality rates and HDI values were correlated by estimating Pearson linear coefficients. The correlation coefficients between the mortality rates of census years 1991, 2000 and 2010 and HDI data of census years 1970, 1980 and 1991 were calculated with discrepancy of two demographic censuses. The linear regression coefficients were estimated with disease as the dependent variable and HDI as the independent variable. In recent decades, there was a reduction in mortality due to DCS in all Rio de Janeiro State municipalities, mainly because of the decline in mortality due to CBVD, which was preceded by an elevation in HDI. There was a strong correlation between the socioeconomic indicator and mortality rates. The HDI progression showed a strong correlation with the decline in mortality due to DCS, signaling to the relevance of improvements in life conditions.

  16. Progression of Mortality due to Diseases of the Circulatory System and Human Development Index in Rio de Janeiro Municipalities

    PubMed Central

    Soares, Gabriel Porto; Klein, Carlos Henrique; Silva, Nelson Albuquerque de Souza e; de Oliveira, Glaucia Maria Moraes

    2016-01-01

    Background Diseases of the circulatory system (DCS) are the major cause of death in Brazil and worldwide. Objective To correlate the compensated and adjusted mortality rates due to DCS in the Rio de Janeiro State municipalities between 1979 and 2010 with the Human Development Index (HDI) from 1970 onwards. Methods Population and death data were obtained in DATASUS/MS database. Mortality rates due to ischemic heart diseases (IHD), cerebrovascular diseases (CBVD) and DCS adjusted by using the direct method and compensated for ill-defined causes. The HDI data were obtained at the Brazilian Institute of Applied Research in Economics. The mortality rates and HDI values were correlated by estimating Pearson linear coefficients. The correlation coefficients between the mortality rates of census years 1991, 2000 and 2010 and HDI data of census years 1970, 1980 and 1991 were calculated with discrepancy of two demographic censuses. The linear regression coefficients were estimated with disease as the dependent variable and HDI as the independent variable. Results In recent decades, there was a reduction in mortality due to DCS in all Rio de Janeiro State municipalities, mainly because of the decline in mortality due to CBVD, which was preceded by an elevation in HDI. There was a strong correlation between the socioeconomic indicator and mortality rates. Conclusion The HDI progression showed a strong correlation with the decline in mortality due to DCS, signaling to the relevance of improvements in life conditions. PMID:27849263

  17. Measurement science in the circulatory system.

    PubMed

    Jones, Casey M; Baker-Groberg, Sandra M; Cianchetti, Flor A; Glynn, Jeremy J; Healy, Laura D; Lam, Wai Yan; Nelson, Jonathan W; Parrish, Diana C; Phillips, Kevin G; Scott-Drechsel, Devon E; Tagge, Ian J; Zelaya, Jaime E; Hinds, Monica T; McCarty, Owen J T

    2014-03-01

    The dynamics of the cellular and molecular constituents of the circulatory system are regulated by the biophysical properties of the heart, vasculature and blood cells and proteins. In this review, we discuss measurement techniques that have been developed to characterize the physical and mechanical parameters of the circulatory system across length scales ranging from the tissue scale (centimeter) to the molecular scale (nanometer) and time scales of years to milliseconds. We compare the utility of measurement techniques as a function of spatial resolution and penetration depth from both a diagnostic and research perspective. Together, this review provides an overview of the utility of measurement science techniques to study the spatial systems of the circulatory system in health and disease.

  18. Measurement science in the circulatory system

    PubMed Central

    Jones, Casey M.; Baker-Groberg, Sandra M.; Cianchetti, Flor A.; Glynn, Jeremy J.; Healy, Laura D.; Lam, Wai Yan; Nelson, Jonathan W.; Parrish, Diana C.; Phillips, Kevin G.; Scott-Drechsel, Devon E.; Tagge, Ian J.; Zelaya, Jaime E.; Hinds, Monica T.; McCarty, Owen J.T.

    2014-01-01

    The dynamics of the cellular and molecular constituents of the circulatory system are regulated by the biophysical properties of the heart, vasculature and blood cells and proteins. In this review, we discuss measurement techniques that have been developed to characterize the physical and mechanical parameters of the circulatory system across length scales ranging from the tissue scale (centimeter) to the molecular scale (nanometer) and time scales of years to milliseconds. We compare the utility of measurement techniques as a function of spatial resolution and penetration depth from both a diagnostic and research perspective. Together, this review provides an overview of the utility of measurement science techniques to study the spatial systems of the circulatory system in health and disease. PMID:24563678

  19. The Circulatory System. Instructional Materials in Anatomy and Physiology for Pennsylvania Health Occupations Programs.

    ERIC Educational Resources Information Center

    National Evaluation Systems, Inc., Amherst, MA.

    This instructional modular unit with instructor's guide provides materials on aspects of one of the major systems of the human body--the circulatory system. Its purpose is to introduce the student to the structures and functions of the human circulatory system--and the interrelationships of the two--and to familiarize the student with some of the…

  20. 78 FR 55081 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-09

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... Monitoring System. The CardioMEMS HF System is a permanently implantable pressure measurement system...

  1. 78 FR 11208 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... approval application for the MitraClip Delivery System sponsored by Abbott Vascular. The system consists...

  2. 77 FR 25183 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-27

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... system consists of the following: A heterologous (bovine) pericardium leaflet valve sutured within a...

  3. 77 FR 66847 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-07

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... remaining pre-Amendment Class III devices. These systems typically consist of a treatment table, pressure...

  4. 76 FR 36548 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... mm and accessories implant system consists of the following: The Edwards SAPIEN Transcatheter Heart...

  5. 75 FR 7282 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-18

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... recommendations and vote on a PMA for the REVO MRI Pacemaker System sponsored by Medtronic. The REVO MRI...

  6. 76 FR 63928 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-14

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of...: ``Medtronic cardiac resynchronization therapy defibrillator (CRT-D) systems are indicated for heart...

  7. 75 FR 81282 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... PMA supplement for the RX Acculink Carotid Stent System, sponsored by Abbott Vascular. The RX...

  8. 78 FR 49272 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... outside the body, is used as a temporary substitute for the heart's intrinsic pacing system until...

  9. 76 FR 56200 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-12

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... and are pre-loaded onto 6 or 7 Fr \\1\\ (diameter of 2 or 2.3 mm) delivery systems. Upon deployment,...

  10. 76 FR 58019 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... sponsored by AtriCure, Inc., for the AtriCure Synergy Ablation System to be used for the treatment of...

  11. 77 FR 16038 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel of... the premarket approval application (PMA) for the HeartWare Ventricular Assist System (HVAS)...

  12. Physics of the Circulatory System.

    ERIC Educational Resources Information Center

    Van Heuvelen, Alan

    1989-01-01

    Discusses some calculations and demonstrations illustrating the role of physics in cardiovascular system. Describes a model for the system, work done by the heart, pressure in blood vessel, and gravitational effects. (YP)

  13. 77 FR 18829 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel...

  14. 78 FR 67365 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Circulatory System Devices Panel of the Medical Devices... (FDA). The meeting will be open to the public. Name of Committee: Circulatory System Devices Panel...

  15. The Circulatory System in Liver Disease.

    PubMed

    Hollenberg, Steven M; Waldman, Brett

    2016-07-01

    In the cirrhotic liver, distortion of the normal liver architecture is caused by structural and vascular changes. Portal hypertension is often associated with a hyperdynamic circulatory syndrome in which cardiac output and heart rate are increased and systemic vascular resistance is decreased. The release of several vasoactive substances is the primary factor involved in the reduction of mesenteric arterial resistance, resulting in sodium and water retention with eventual formation of ascites. Management of these patients with acute cardiac dysfunction often requires invasive hemodynamic monitoring in an intensive care unit setting to tailor decisions regarding use of fluids and vasopressors. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Children's Beliefs about the Human Circulatory System: An Aid for Teachers Regarding the Role Intuitive Beliefs Play in the Development of Formal Concepts in 7-14-Year Olds. Report No. 82:16.

    ERIC Educational Resources Information Center

    Catherall, Robin W.

    This exploratory study was aimed at uncovering children's beliefs and ideas about the human circulatory system. Thirty-two subjects, aged 7 to 14 years, were interviewed using a modification of Piaget's clinical method. The data were analyzed by developing a conceptual inventory of beliefs for each of five research questions. It was found that the…

  17. Children's Beliefs about the Human Circulatory System: An Aid for Teachers Regarding the Role Intuitive Beliefs Play in the Development of Formal Concepts in 7-14-Year Olds. Report No. 82:16.

    ERIC Educational Resources Information Center

    Catherall, Robin W.

    This exploratory study was aimed at uncovering children's beliefs and ideas about the human circulatory system. Thirty-two subjects, aged 7 to 14 years, were interviewed using a modification of Piaget's clinical method. The data were analyzed by developing a conceptual inventory of beliefs for each of five research questions. It was found that the…

  18. A pacemaker powered by an implantable biofuel cell operating under conditions mimicking the human blood circulatory system--battery not included.

    PubMed

    Southcott, Mark; MacVittie, Kevin; Halámek, Jan; Halámková, Lenka; Jemison, William D; Lobel, Robert; Katz, Evgeny

    2013-05-07

    Biocatalytic electrodes made of buckypaper were modified with PQQ-dependent glucose dehydrogenase on the anode and with laccase on the cathode and were assembled in a flow biofuel cell filled with serum solution mimicking the human blood circulatory system. The biofuel cell generated an open circuitry voltage, Voc, of ca. 470 mV and a short circuitry current, Isc, of ca. 5 mA (a current density of 0.83 mA cm(-2)). The power generated by the implantable biofuel cell was used to activate a pacemaker connected to the cell via a charge pump and a DC-DC converter interface circuit to adjust the voltage produced by the biofuel cell to the value required by the pacemaker. The voltage-current dependencies were analyzed for the biofuel cell connected to an Ohmic load and to the electronic loads composed of the interface circuit, or the power converter, and the pacemaker to study their operation. The correct pacemaker operation was confirmed using a medical device - an implantable loop recorder. Sustainable operation of the pacemaker was achieved with the system closely mimicking human physiological conditions using a single biofuel cell. This first demonstration of the pacemaker activated by the physiologically produced electrical energy shows promise for future electronic implantable medical devices powered by electricity harvested from the human body.

  19. Permanent circulatory support systems at the Pennsylvania State University.

    PubMed

    Weiss, W J; Rosenberg, G; Snyder, A J; Cleary, T J; Gaumond, R P; Geselowitz, D B; Pierce, W S

    1990-02-01

    Permanent circulatory support systems are required for patients in whom myocardial damage is irreversible and cardiac transplantation is not possible. Two systems are described which provide long term circulatory support: the left ventricular assist system and the total artificial heart. These systems are based on the design of a pusher plate actuated blood pump, driven by a small brushless dc electric motor and rollerscrew driver. An implantable motor controller maintains suitable physiologic flow rates for both systems and controls left-right balance in the total artificial heart. Other parts of the system include an intra-thoracic compliance chamber, transcutaneous energy and data transmission system, and internal and external batteries.

  20. [The diseases of circulatory system in employees of railway transport].

    PubMed

    Molodtsov, R N; Shemetova, G N

    2013-01-01

    The article presents the epidemiologic and medical social aspects of diseases of circulatory system in employees of railway transport in 2000-2010 exemplified by Privolzhskiy railroad. The established tendencies in prevalence of pathology of cardio-vascular system in railroad workers makes the issues of practical implementation of priority of prevention in the organization of medical care to this group of patients to come to foreground. The main directions for complex prevention of diseases of circulatory system in employees of railway transport are presented.

  1. Influence of compliance on flow rate waveforms in hydraulic circuits for in vitro modeling the human circulatory system.

    PubMed

    He, Wenbo; Wang, Yuan; Gong, Xiaoyan

    2014-01-01

    Generating an artificial blood flow in a circle system is an important step in hemodynamic research; thus, the influence of circle system components on the pulsatile flow wave forms should be investigated. In this study, a circle system was built, in which two solenoid valves were controlled by a timer to transform a constant flow into a pulsatile one, and two customized compliances with five different aeration volumes were set up upstream and downstream of the test chamber, achieving twenty-five different wave forms. Then, the influence of the compliance settings on the flow rate wave form was investigated. From the experimental data, it can be concluded that the absolute value of the maximum value and the minimum value of the wave forms increases along the aeration of the downstream compliance but decreases along the aeration of the upstream compliance. For the second maximum value and the offset between the maximum value and the minimum value, remarkable differences were obtained between runs with aeration of zero compliance and nonzero compliance. Finally, an emulational flow was achieved with the up- and downstream aeration volume equaling 360 mL and 180 mL, respectively, which fit the realistic wave form well.

  2. Monoacylglycerol-enriched oil increases EPA/DHA delivery to circulatory system in humans with induced lipid malabsorption conditions.

    PubMed

    Cruz-Hernandez, Cristina; Destaillats, Frédéric; Thakkar, Sagar K; Goulet, Laurence; Wynn, Emma; Grathwohl, Dominik; Roessle, Claudia; de Giorgi, Sara; Tappy, Luc; Giuffrida, Francesca; Giusti, Vittorio

    2016-12-01

    It was hypothesized that under induced lipid malabsorption/maldigestion conditions, an enriched sn-1(3)-monoacylglycerol (MAG) oil may be a better carrier for n-3 long-chain PUFAs (LC-PUFAs) compared with triacylglycerol (TAG) from fish oil. This monocentric double blinded clinical trial examined the accretion of EPA (500 mg/day) and DHA (300 mg/day) when consumed as TAG or MAG, into the erythrocytes, plasma, and chylomicrons of 45 obese (BMI ≥30 kg/m(2) and ≤40 kg/m(2)) volunteers who were and were not administered Orlistat, an inhibitor of pancreatic lipases. Intake of MAG-enriched oil resulted in higher accretion of LC-PUFAs than with TAG, the concentrations of EPA and DHA in erythrocytes being, respectively, 72 and 24% higher at 21 days (P < 0.001). In addition, MAG increased the plasma concentration of EPA by 56% (P < 0.001) as compared with TAG. In chylomicrons, MAG intake yielded higher levels of EPA with the area under the curve (0-10 h) of EPA being 55% greater (P = 0.012). In conclusion, in obese human subjects with Orlistat-induced lipid maldigestion/malabsorption conditions, LC-PUFA MAG oil increased LC-PUFA levels in erythrocytes, plasma, and chylomicrons to a greater extent than TAG. These results indicate that MAG oil might require minimal enzymatic digestion prior to intestinal uptake and transfer across the epithelial barrier.

  3. Histological study of the circulatory system of human dental pulp from individuals under local anesthesia and electro-acupuncture.

    PubMed

    Ueki, S; Iwai-Liao, Y; Han, K S; Higashi, Y

    1995-03-01

    A transmission electron microscopic (TEM) study was conducted on dental pulp obtained from patients under acupuncture or infiltration local analgesia. It was difficult to differentiate lymphatic circulation in the dental pulp that received infiltration anesthesia, because the vessels were constricted, congested, and showed stasis and thrombosis. On the other hand, the dental pulp that received acupuncture showed normal arterioles, capillaries, and venules, as well as some lymph capillaries and small efferent lymphatic vessels that measured about 8 microns and 100 microns in diameter, respectively. The lymphatic endothelial walls had many intercellular gaps, an imperfect basal lamina, and a few discontinuous pericytes. Between the openings in the lymphatic vessels, there were bundles of junctional filaments extending towards the dental pulp connective tissue. Therefore, the lymphatic system, which contains mainly B-3-alpha capillaries, is a leaky tissue for regulating fluid in the dental pulp.

  4. From Head to Toe: Respiratory, Circulatory, and Skeletal Systems. Book 3.

    ERIC Educational Resources Information Center

    Wiebe, Arthur, Ed.; And Others

    Designed to supplement curricular programs dealing with the human body, this booklet offers an activity-based, student-oriented approach for middle school teachers and students. Twelve activities focus on principles and skills related to the respiratory, circulatory, and skeletal systems. Each activity consists of student sheets and a teacher's…

  5. From Head to Toe: Respiratory, Circulatory, and Skeletal Systems. Book 3.

    ERIC Educational Resources Information Center

    Wiebe, Arthur, Ed.; And Others

    Designed to supplement curricular programs dealing with the human body, this booklet offers an activity-based, student-oriented approach for middle school teachers and students. Twelve activities focus on principles and skills related to the respiratory, circulatory, and skeletal systems. Each activity consists of student sheets and a teacher's…

  6. NUCLEAR-FUELED CIRCULATORY SUPPORT SYSTEMS IV: RADIOLOGIC PERSPECTIVES

    PubMed Central

    Huffman, F. N.; Norman, J. C.

    1974-01-01

    If an implantable artificial heart can be developed, it should prove beneficial to a significant group of patients. A variety of energy sources, such as biologic, electromagnetic, and nuclear, are under evaluation. Currently, biologic fuel cell technology is not sufficiently advanced to permit its extrapolation to the power levels required for implantable circulatory support systems. Electromagnetic systems have the disadvantage of heavy batteries of considerable bulk requiring frequent recharging. Radioisotope-fueled thermal engine systems have the potential of providing degrees of freedom not possible with rechargeable units. However, radiosotope circulatory support systems subject their recipients to prolonged intracorporeal radiation, add to environmental background radiation, and constitute an exceedingly small, but finite, hazard due to possible violation of fuel containment. PMID:15215965

  7. Mass Transport: Circulatory System with Emphasis on Nonendothermic Species.

    PubMed

    Crossley, Dane A; Burggren, Warren W; Reiber, Carl L; Altimiras, Jordi; Rodnick, Kenneth J

    2016-12-06

    Mass transport can be generally defined as movement of material matter. The circulatory system then is a biological example given its role in the movement in transporting gases, nutrients, wastes, and chemical signals. Comparative physiology has a long history of providing new insights and advancing our understanding of circulatory mass transport across a wide array of circulatory systems. Here we focus on circulatory function of nonmodel species. Invertebrates possess diverse convection systems; that at the most complex generate pressures and perform at a level comparable to vertebrates. Many invertebrates actively modulate cardiovascular function using neuronal, neurohormonal, and skeletal muscle activity. In vertebrates, our understanding of cardiac morphology, cardiomyocyte function, and contractile protein regulation by Ca2+ highlights a high degree of conservation, but differences between species exist and are coupled to variable environments and body temperatures. Key regulators of vertebrate cardiac function and systemic blood pressure include the autonomic nervous system, hormones, and ventricular filling. Further chemical factors regulating cardiovascular function include adenosine, natriuretic peptides, arginine vasotocin, endothelin 1, bradykinin, histamine, nitric oxide, and hydrogen sulfide, to name but a few. Diverse vascular morphologies and the regulation of blood flow in the coronary and cerebral circulations are also apparent in nonmammalian species. Dynamic adjustments of cardiovascular function are associated with exercise on land, flying at high altitude, prolonged dives by marine mammals, and unique morphology, such as the giraffe. Future studies should address limits of gas exchange and convective transport, the evolution of high arterial pressure across diverse taxa, and the importance of the cardiovascular system adaptations to extreme environments. © 2017 American Physiological Society. Compr Physiol 7:17-66, 2017. Copyright © 2017 John

  8. [Caffeine and adaptive changes in the circulatory system during pregnancy].

    PubMed

    Cendrowska-Pinkosz, Monika; Dworzański, Wojciech; Krauze, Magdalena; Burdan, Franciszek

    2017-01-23

    Adaptive physiological changes that occur in pregnant women can fluctuate with the intake of substances with proven, adverse biological effect on the body. Due to the fact that caffeine is one of the most chronically used xenobiotics, the impact of consuming caffeine on adaptive processes in the circulatory system of a pregnant women required a research. Many researchers emphasise its negative effect on the circulatory system of the mother and her offspring. However, in spite of years of observation, there is no clear answer to what extent dose or in what period of time the caffeine modulates the adaptive processes during pregnancy. Because of the potential risk the supply of caffeine during pregnancy should be subjected to considerable restrictions.

  9. Functional stability of cerebral circulatory system

    NASA Technical Reports Server (NTRS)

    Moskalenko, Y. Y.

    1980-01-01

    The functional stability of the cerebral circulation system seems to be based on the active mechanisms and on those stemming from specific of the biophysical structure of the system under study. This latter parameter has some relevant criteria for its quantitative estimation. The data obtained suggest that the essential part of the mechanism for active responses of cerebral vessels which maintains the functional stability of this portion of the vascular system, consists of a neurogenic component involving central nervous structures localized, for instance, in the medulla oblongata.

  10. I.4. Biofluid mechanics & the circulatory system.

    PubMed

    Verdonck, Pascal; Dumont, Kris

    2010-01-01

    A fluid is a medium which deforms, or undergoes motion, continuously under the action of a shearing stress and includes liquids and gases. Applying biofluid mechanics to the cardiovascular system requires knowledge of anatomy and geometry, pressure data and blood flow, volume and velocity measurements. A good example is the assessment of the haemodynamics of biological and mechanical heart valves.

  11. [Prevention of circulatory system diseases in underground mining workers].

    PubMed

    Vlasova, E M; Alexeyev, M B; Shliapnikov, D M; Nosov, A E; Barannikov, V G

    2015-01-01

    The article covers results of preventive measures in workers engaged into underground mining. Those measures are aimed to prevent occupationally mediated health disorders resulting in circulatory diseases. The prophylaxis was proven effective on premorbid condition--that was demonstrated in reliable decrease of cause-effect relationship intensity for health disorders in workers subjected to prophylactic measures. Transitory disablement morbidity due to cicrulatory system diseases decreased. Situational modelling of risk changes for the studied group demonstrated changes of diseases risk under medical prophylactic measures. After the prophylaxis, the risk demonstrated 3.1 times decrease.

  12. A model for transport and dispersion in the circulatory system based on the vascular fractal tree.

    PubMed

    Dokoumetzidis, Aristides; Macheras, Panos

    2003-03-01

    Materials are distributed throughout the body of mammals by fractal networks of branching tubes. Based on the scaling laws of the fractal structure, the vascular tree is reduced to an equivalent one-dimensional, tube model. A dispersion-convection partial differential equation with constant coefficients describes the heterogeneous concentration profile of an intravascular tracer in the vascular tree. A simple model for the mammalian circulatory system is built in entirely physiological terms consisting of a ring shaped, one-dimensional tube which corresponds to the arterial, venular, and pulmonary trees, successively. The model incorporates the blood flow heterogeneity of the mammalian circulatory system. Model predictions are fitted to published concentration-time data of indocyanine green injected in humans and dogs. Close agreement was found with parameter values within the expected physiological range.

  13. The role of brain gaseous transmitters in the regulation of the circulatory system.

    PubMed

    Ufnal, Marcin; Sikora, Mariusz

    2011-09-01

    A number of neurotransmitters, including biologically active gases namely, nitric oxide (NO), hydrogen sulfide (H2S) and carbon monoxide (CO) have been postulated to play an important role in the control of the cardiovascular system by the brain. The attention of researchers has been focused on NO in particular. It has been shown that pharmacological manipulation of NO concentration in the brain produces significant changes in circulatory parameters. Furthermore, significant alterations in the brain NO system have been found in animal models of human cardiovascular diseases. These findings imply that NO in the brain may become a promising target for new treatment strategies. Although H2S and CO have also been proved to serve as transmitters in the central nervous system, their role in the neurogenic regulation of the cardiovascular system remains more obscure. Interestingly, increased synthesis of NO, H2S and CO is found in inflammation and it appears that the gases mediate some of the circulatory responses to inflammatory stimuli. In this review we discuss the role of brain gaseous transmitters in the control of the circulatory system in health and disease.

  14. Bonghan circulatory system as an extension of acupuncture meridians.

    PubMed

    Soh, Kwang-Sup

    2009-06-01

    The Bonghan system is a newly-discovered circulatory system, which corresponds to classical acupuncture meridians and was discovered in the early 1960s by Bonghan Kim. Despite its potential importance in biology and medicine, it has been ignored or forgotten for a long time. Only recently have most of its significant parts, such as the Bonghan system (BHS) inside blood or lymph vessels, on the surfaces of internal organs, and in brain ventricles, been confirmed. For this, novel methods using modern technology were necessary because Bonghan Kim did not describe his methods. For example, Among other methods, the discovery of a BHS-specific dye, trypan blue, was one of the most important original contributions that made BHS observation possible. With this technique, the BHS in adipose tissue became traceable, and the BHS was discovered on the fascia surrounding tumor tissues, a finding which may have great significance in relation to serious health problems in modern society, namely, obesity and cancer.

  15. [Impact of Macao Medical Voucher Program on health outcomes of the residents: changes of mortality from circulatory system diseases].

    PubMed

    Zhang, Jinghua; Pang, Chuan; Tam, Kwoping

    2014-07-01

    To examine whether the implementation of Macao Medical Voucher Program has helped promote the health outcomes of the residents in the case of mortality from circulatory system diseases. Based on 144 monthly observations of the mortality from circulatory system diseases in Macao during 2001-2012, we carried out a trend analysis of the time series to identify significant differences in the mortality data after the implementation of the Medical Voucher in Macao. This study was controlled for the compounding factors including medical resources (numbers of physicians, nurses and patient beds per thousand population and public healthcare expenditure), economic development level (GDP per capita), social human development level, population aging factor, natural seasonal effects and long-term trends. During 2010-2012 when the Medical Voucher Program in Macao was implemented, the annual mortality rates from circulatory system diseases were significantly lowered by 24% as compared with those recorded during 2001-2009 (P<0.01), which was equivalent to avoiding 123 deaths related of circulatory system diseases per year. Evidence in this study suggests a robust connection between the timing of the implementation of Macao Medical Voucher Program and a significant decrease in the mortality from circulatory system diseases in Macao, but their causal relationship awaits confirmation in further research.

  16. Adhesion Molecules: Master Controllers of the Circulatory System.

    PubMed

    Schmidt, Eric P; Kuebler, Wolfgang M; Lee, Warren L; Downey, Gregory P

    2016-03-15

    This manuscript will review our current understanding of cellular adhesion molecules (CAMs) relevant to the circulatory system, their physiological role in control of vascular homeostasis, innate and adaptive immune responses, and their importance in pathophysiological (disease) processes such as acute lung injury, atherosclerosis, and pulmonary hypertension. This is a complex and rapidly changing area of research that is incompletely understood. By design, we will begin with a brief overview of the structure and classification of the major groups of adhesion molecules and their physiological functions including cellular adhesion and signaling. The role of specific CAMs in the process of platelet aggregation and hemostasis and leukocyte adhesion and transendothelial migration will be reviewed as examples of the complex and cooperative interplay between CAMs during physiological and pathophysiological processes. The role of the endothelial glycocalyx and the glycobiology of this complex system related to inflammatory states such as sepsis will be reviewed. We will then focus on the role of adhesion molecules in the pathogenesis of specific disease processes involving the lungs and cardiovascular system. The potential of targeting adhesion molecules in the treatment of immune and inflammatory diseases will be highlighted in the relevant sections throughout the manuscript.

  17. Design of a hydraulic analog of the circulatory system for evaluating artificial hearts.

    PubMed

    Donovan, F M

    1975-01-01

    A major problem in improving artificial heart designs is the absence of methods for accurate in vitro testing of artificial heart systems. A mock circulatory system has been constructed which hydraulically simulates the systemic and pulmonary circulations of the normal human. The device is constructed of 1/2 in. acrylic sheet and has overall dimensions of 24 in. wide, 16 in. tall, and 8 in. deep. The artificial heart to be tested is attached to the front of the device, and pumps fluid from the systemic venous chamber into the pulmonary arterial chamber and from the pulmonary venous chamber into the systemic arterial chamber. Each of the four chambers is hermetically sealed. The compliance of each chamber is determined by the volume of air trapped above the fluid in that chamber. The pulmonary and systemic resistances are set automatically by bellows-operated valves to simulate the barroreceptor response in the systemic arteries and the passive pulmonary resistance response in the pulmonary arteries. Cardiac output is measured by a turbine flowmeter in the systemic circulation. Results using the Kwan-Gett artificial heart show a good comparison between the mock circulatory system response and the calf response.

  18. Endoglin regulates mural cell adhesion in the circulatory system.

    PubMed

    Rossi, Elisa; Smadja, David M; Boscolo, Elisa; Langa, Carmen; Arevalo, Miguel A; Pericacho, Miguel; Gamella-Pozuelo, Luis; Kauskot, Alexandre; Botella, Luisa M; Gaussem, Pascale; Bischoff, Joyce; Lopez-Novoa, José M; Bernabeu, Carmelo

    2016-04-01

    The circulatory system is walled off by different cell types, including vascular mural cells and podocytes. The interaction and interplay between endothelial cells (ECs) and mural cells, such as vascular smooth muscle cells or pericytes, play a pivotal role in vascular biology. Endoglin is an RGD-containing counter-receptor for β1 integrins and is highly expressed by ECs during angiogenesis. We find that the adhesion between vascular ECs and mural cells is enhanced by integrin activators and inhibited upon suppression of membrane endoglin or β1-integrin, as well as by addition of soluble endoglin (SolEng), anti-integrin α5β1 antibody or an RGD peptide. Analysis of different endoglin mutants, allowed the mapping of the endoglin RGD motif as involved in the adhesion process. In Eng (+/-) mice, a model for hereditary hemorrhagic telangectasia type 1, endoglin haploinsufficiency induces a pericyte-dependent increase in vascular permeability. Also, transgenic mice overexpressing SolEng, an animal model for preeclampsia, show podocyturia, suggesting that SolEng is responsible for podocytes detachment from glomerular capillaries. These results suggest a critical role for endoglin in integrin-mediated adhesion of mural cells and provide a better understanding on the mechanisms of vessel maturation in normal physiology as well as in pathologies such as preeclampsia or hereditary hemorrhagic telangiectasia.

  19. Evaluation of exercise-respiratory system modifications and preliminary respiratory-circulatory system integration scheme

    NASA Technical Reports Server (NTRS)

    Gallagher, R. R.

    1974-01-01

    The respiratory control system, functioning as an independent system, is presented with modifications of the exercise subroutine. These modifications illustrate an improved control of ventilation rates and arterial and compartmental gas tensions. A very elementary approach to describing the interactions of the respiratory and circulatory system is presented.

  20. [Influence of anandamide, the endogenous agonist of cannabinoid receptors on the circulatory system].

    PubMed

    Kwolek, Grzegorz; Zakrzeska, Agnieszka; Kozłowska, Hanna; Malinowska, Barbara

    2005-05-19

    Cannabinoids, the active ingredients of Cannabis sativa, have been used by humans as hallucinogens and therapeutic agents for thousands of years. These agents are now known to act through the cannabinoid CB1 and CB2 receptors. The recent discovery of endogenous cannabinoids and the fact that they are involved in the pathology of hypotension associated with hemorrhage, sepsis, cirrhosis, and myocardial infarction indicate that cannabinoids play a greater role in human and animal pathophysiology than initially anticipated. Anandamide is the first of the endogenous cannabinoid ligands discovered. Its intravenous administration produces a characteristic three-phase response in the circulatory systems of experimental animals: In phase 1--a short-lasting decrease in heart rate and systemic blood pressure is related to activation of vanilloid TRPV1 receptors. In phase 2 an increase in blood pressure involves multiple mechanisms, both central (probably through the rostral ventrolateral medulla) and peripheral (vascular, Ca2+-dependent). In phase 3 there is a prolonged decrease in blood pressure and sometimes bradycardia, related to the activation of cannabinoid CB1 and vanilloid TRPV1 receptors. On the basis of this three-phase mechanism, the present paper intends to describe the participation of anandamide in the circulatory system under physiological and pathophysiological conditions. It also discusses the possibility of applying cannabinoid ligands as new therapeutic agents for the treatment of some pathologies.

  1. A microfluidic circulatory system integrated with capillary-assisted pressure sensors.

    PubMed

    Chen, Yangfan; Chan, Ho Nam; Michael, Sean A; Shen, Yusheng; Chen, Yin; Tian, Qian; Huang, Lu; Wu, Hongkai

    2017-02-14

    The human circulatory system comprises a complex network of blood vessels interconnecting biologically relevant organs and a heart driving blood recirculation throughout this system. Recreating this system in vitro would act as a bridge between organ-on-a-chip and "body-on-a-chip" and advance the development of in vitro models. Here, we present a microfluidic circulatory system integrated with an on-chip pressure sensor to closely mimic human systemic circulation in vitro. A cardiac-like on-chip pumping system is incorporated in the device. It consists of four pumping units and passive check valves, which mimic the four heart chambers and heart valves, respectively. Each pumping unit is independently controlled with adjustable pressure and pump rate, enabling users to control the mimicked blood pressure and heartbeat rate within the device. A check valve is located downstream of each pumping unit to prevent backward leakage. Pulsatile and unidirectional flow can be generated to recirculate within the device by programming the four pumping units. We also report an on-chip capillary-assisted pressure sensor to monitor the pressure inside the device. One end of the capillary was placed in the measurement region, while the other end was sealed. Time-dependent pressure changes were measured by recording the movement of the liquid-gas interface in the capillary and calculating the pressure using the ideal gas law. The sensor covered the physiologically relevant blood pressure range found in humans (0-142.5 mmHg) and could respond to 0.2 s actuation time. With the aid of the sensor, the pressure inside the device could be adjusted to the desired range. As a proof of concept, human normal left ventricular and arterial pressure profiles were mimicked inside this device. Human umbilical vein endothelial cells (HUVECs) were cultured on chip and cells can respond to mechanical forces generated by arterial-like flow patterns.

  2. Mortality from Circulatory System Diseases and Malformations in Children in the State of Rio de Janeiro.

    PubMed

    Salim, Thais Rocha; Soares, Gabriel Porto; Klein, Carlos Henrique; Oliveira, Glaucia Maria Moraes de

    2016-06-01

    The epidemiological profile of mortality in a population is important for the institution of measures to improve health care and reduce mortality Objective: To estimate mortality rates and the proportional mortality from cardiovascular diseases and malformations of the circulatory system in children and adolescents. This is a descriptive study of mortality from cardiovascular diseases, malformations of the circulatory system, from all causes, ill-defined causes and external causes in children and adolescents in the state of Rio de Janeiro from 1996 to 2012. Populations were obtained from the Brazilian Institute of Geography and Statistics (Instituto Brasileiro de Geografia e Estatística - IBGE) and deaths obtained from the Department of Informatics of the Unified Health System (DATASUS)/Ministry of Health. There were 115,728 deaths from all causes, 69,757 in males. The annual mortality from cardiovascular diseases was 2.7/100,000 in men and 2.6/100,000 in women. The annual mortality from malformations of the circulatory system was 7.5/100,000 in men and 6.6/100,000 in women. Among the specific causes of circulatory diseases, cardiomyopathies had the highest rates of annual proportional mortality, and from malformations of the circulatory system, it occurred due to unspecified malformations of the circulatory system, at all ages and in both genders. Mortality from malformations of the circulatory system was most striking in the first years of life, while cardiovascular diseases were more relevant in adolescents. Low access to prenatal diagnosis or at birth probably prevented the proper treatment of malformations of the circulatory system.

  3. Mortality from Circulatory System Diseases and Malformations in Children in the State of Rio de Janeiro

    PubMed Central

    Salim, Thais Rocha; Soares, Gabriel Porto; Klein, Carlos Henrique; de Oliveira, Glaucia Maria Moraes

    2016-01-01

    Background The epidemiological profile of mortality in a population is important for the institution of measures to improve health care and reduce mortality Objective To estimate mortality rates and the proportional mortality from cardiovascular diseases and malformations of the circulatory system in children and adolescents. Methods This is a descriptive study of mortality from cardiovascular diseases, malformations of the circulatory system, from all causes, ill-defined causes and external causes in children and adolescents in the state of Rio de Janeiro from 1996 to 2012. Populations were obtained from the Brazilian Institute of Geography and Statistics (Instituto Brasileiro de Geografia e Estatística - IBGE) and deaths obtained from the Department of Informatics of the Unified Health System (DATASUS)/Ministry of Health. Results There were 115,728 deaths from all causes, 69,757 in males. The annual mortality from cardiovascular diseases was 2.7/100,000 in men and 2.6/100,000 in women. The annual mortality from malformations of the circulatory system was 7.5/100,000 in men and 6.6/100,000 in women. Among the specific causes of circulatory diseases, cardiomyopathies had the highest rates of annual proportional mortality, and from malformations of the circulatory system, it occurred due to unspecified malformations of the circulatory system, at all ages and in both genders. Conclusion Mortality from malformations of the circulatory system was most striking in the first years of life, while cardiovascular diseases were more relevant in adolescents. Low access to prenatal diagnosis or at birth probably prevented the proper treatment of malformations of the circulatory system. PMID:27192384

  4. Gut Bacteria and Hydrogen Sulfide: The New Old Players in Circulatory System Homeostasis.

    PubMed

    Tomasova, Lenka; Konopelski, Piotr; Ufnal, Marcin

    2016-11-17

    Accumulating evidence suggests that gut bacteria play a role in homeostasis of the circulatory system in mammals. First, gut bacteria may affect the nervous control of the circulatory system via the sensory fibres of the enteric nervous system. Second, gut bacteria-derived metabolites may cross the gut-blood barrier and target blood vessels, the heart and other organs involved in the regulation of the circulatory system. A number of studies have shown that hydrogen sulfide (H₂S) is an important biological mediator in the circulatory system. Thus far, research has focused on the effects of H₂S enzymatically produced by cardiovascular tissues. However, some recent evidence indicates that H₂S released in the colon may also contribute to the control of arterial blood pressure. Incidentally, sulfate-reducing bacteria are ubiquitous in mammalian colon, and H₂S is just one among a number of molecules produced by the gut flora. Other gut bacteria-derived compounds that may affect the circulatory system include methane, nitric oxide, carbon monoxide, trimethylamine or indole. In this paper, we review studies that imply a role of gut microbiota and their metabolites, such as H₂S, in circulatory system homeostasis.

  5. The Circulatory System [and] Instructor's Guide: The Circulatory System. Health Occupations Education Module: Instructional Materials in Anatomy and Physiology for Pennsylvania Health Occupations Programs.

    ERIC Educational Resources Information Center

    National Evaluation Systems, Inc., Amherst, MA.

    This module on the circulatory system is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. It is part of an eight-unit subset on anatomy and physiology within the set of 17 modules. Following a preface which explains to the student how to use the…

  6. The Pulsed Flow Algorithm (PFA) Applied to Coupled Respiratory and Circulatory Systems

    NASA Astrophysics Data System (ADS)

    Staples, A.; Oran, E.; Boris, J.; Kaplan, C.; Kailasanath, K.

    2007-11-01

    The Pulsed Flow Equations (PFE) are a set of coupled partial differential equations designed to capture features particularly relevant to internal flows through flexible elastic channels, such as flows in physiological systems in biological organisms, and hydraulics systems. The equations are an extension of the standard one-dimensional fluid flow equations that, in addition, are able to capture two-dimensional diffusion, branching, transport, viscous, and other effects. A limiting case of the equations is the standard one-dimensional fluid flow equations. The equations are discretized and solved partially using an asymptotic solution, after which they reduce to tridiagonal form. The solution formalism can be applied to many types of complex networks of internal flows, and solves these problems, including some important two-dimensional effects, at the cost of a one-dimensional tridiagonal computation. Here we apply the PFA to describe a coupled circulatory and respiratory system calibrated to the average human body.

  7. Noninvasive optoacoustic system for rapid diagnostics and management of circulatory shock

    NASA Astrophysics Data System (ADS)

    Esenaliev, Rinat O.; Petrov, Irene Y.; Petrov, Yuriy; Kinsky, Michael; Prough, Donald S.

    2012-02-01

    Circulatory shock is lethal, if not promptly diagnosed and effectively treated. Typically, circulatory shock resuscitation is guided by blood pressure, heart rate, and mental status, which have poor predictive value. In patients, in whom early goaldirected therapy was applied using central venous oxygenation measurement, a substantial reduction of mortality was reported (from 46.5% to 30%). However, central venous catheterization is invasive, time-consuming and often results in complications. We proposed to use the optoacoustic technique for noninvasive, rapid assessment of central venous oxygenation. In our previous works we demonstrated that the optoacoustic technique can provide measurement of blood oxygenation in veins and arteries due to high contrast and high resolution. In this work we developed a novel optoacoustic system for noninvasive, automatic, real-time, and continuous measurement of central venous oxygenation. We performed pilot clinical tests of the system in human subjects with different oxygenation in the internal jugular vein and subclavian vein. A novel optoacoustic interface incorporating highly-sensitive optoacoustic probes and standard ultrasound imaging probes were developed and built for the study. Ultrasound imaging systems Vivid i and hand-held Vscan (GE Healthcare) as well as Site-Rite 5 (C.R. Bard) were used in the study. We developed a special algorithm for oxygenation monitoring with minimal influence of overlying tissue. The data demonstrate that the system provides precise measurement of venous oxygenation continuously and in real time. Both current value of the venous oxygenation and trend (in absolute values and for specified time intervals) are displayed in the system. The data indicate that: 1) the optoacoustic system developed by our group is capable of noninvasive measurement of blood oxygenation in specific veins; 2) clinical ultrasound imaging systems can facilitate optoacoustic probing of specific blood vessels; 3) the

  8. [The present state of knowledge concerning the effect of electromagnetic fields of 50/60 Hz on the circulatory system and the autonomic nervous system].

    PubMed

    Indulski, J A; Bortkiewicz, A; Zmyślony, M

    1997-01-01

    Diseases of the circulatory system together with neoplastic diseases are recognised as the major health problem in the contemporary world. Their origin and aggravation may be related to the exposure to electromagnetic fields (EMFs) since theoretically, disorders in the functioning of the circulatory system are most likely due to electric impulses generated in it by external magnetic fields. The nervous system, including its autonomic part which regulates, among others, the functioning of the circulatory system, because of its electric nature is another system which may be disturbed by EMFs. From the 1960s, biological studies on the effects of power-line frequency EMFs have been carried out in many countries. In view of the applied study model, four main directions of these studies can be identified: in vitro and in vivo animal experiments, experimental studies on humans, clinical and epidemiological studies. Experimental studies on animals and humans have yielded ambiguous and very often contradictory results. Some of them indicate that EMF contributes to slowing down the cardiac rhythm and the stroke volume of the left ventricle, other results suggest their acceleration, and still other show no differences. The results of clinical studies performed in many countries in different groups of workers exposed to power-line frequency EMFs have not produced the evidence for drawing unequivocal conclusions. Again some studies reveal that those exposed show disorders in neurovegetative and blood pressure regulations (hypotension or hypertension) as well as in cardiac rhythm (bradycardia or tachycardia). Other studies do not confirm harmful effect of EMF on the circulatory system. Therefore, it is not feasible to find out, on the basis of these studies, whether and how chronic exposure to power-line frequency EMFs influences the functioning of the circulatory system, the more so as ECG standard recording has been to date the only diagnostic method, and according to the

  9. Bilingual Skills Training Program. Barbering/Cosmetology. Module 10.0: Circulatory System.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on the circulatory or vascular system is the tenth of ten (CE 028 308-318) in the barbering/cosmetology course of a bilingual skills training program. (A Vocabulary Development Workbook for modules 6-10 is available as CE 028 313.) The course is designed to furnish theoretical and laboratory experience. Module objectives are for…

  10. The Decapod Crustacean Circulatory System: A Case That Is neither Open nor Closed

    NASA Astrophysics Data System (ADS)

    McGaw, Iain J.

    2005-02-01

    Historically, the decapod crustacean circulatory system has been classed as open. However, recent work on the blue crab, Callinectes sapidus, suggests the circulatory system may be more complex than previously described. Corrosion casting techniques were refined and used to map the circulatory system of a variety of crab species (order: Decapoda; family: Cancridae) to determine if the complexity observed in the blue crab was present in other species. Seven arteries arose from the single chambered heart. The anterior aorta, the paired anterolateral arteries, and the paired hepatic arteries exited from the anterior aspect of the heart. The small-diameter posterior aorta exited posteriorly from the heart. Exiting from the ventral surface of the heart, the sternal artery branched to supply the legs and mouthparts of the crab. These arteries were more complex than previously described, with arterioles perfusing all areas of the body. The arterioles split into fine capillary-like vessels. Most of these capillaries were blind ending. However, in several areas (antennal gland, supraesophageal ganglion) complete capillary beds were present. After passing through the capillary-like vessels, blood drained into a series of sinuses. However, rather than being arbitrary spaces as previously described, scanning electron micrographs showed the sinuses to be distinct units. Most of the sinuses formed a series of flattened membrane-bound lacunae. This complexity may qualify the decapod crustacean circulatory system as one that is "partially closed" rather than open.

  11. Bilingual Skills Training Program. Barbering/Cosmetology. Module 10.0: Circulatory System.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on the circulatory or vascular system is the tenth of ten (CE 028 308-318) in the barbering/cosmetology course of a bilingual skills training program. (A Vocabulary Development Workbook for modules 6-10 is available as CE 028 313.) The course is designed to furnish theoretical and laboratory experience. Module objectives are for…

  12. [Application of artificial neural networks in forecasting the number of circulatory system diseases death toll].

    PubMed

    Zhang, Ying; Shao, Yi; Shang, Kezheng; Wang, Shigong; Wang, Jinyan

    2014-09-01

    Set up the model of forecasting the number of circulatorys death toll based on back-propagation (BP) artificial neural networks discuss the relationship between the circulatory system diseases death toll meteorological factors and ambient air pollution. The data of tem deaths, meteorological factors, and ambient air pollution within the m 2004 to 2009 in Nanjing were collected. On the basis of analyzing the ficient between CSDDT meteorological factors and ambient air pollution, leutral network model of CSDDT was built for 2004 - 2008 based on factors and ambient air pollution within the same time, and the data of 2009 est the predictive power of the model. There was a closely system diseases relationship between meteorological factors, ambient air pollution and the circulatory system diseases death toll. The ANN model structure was 17 -16 -1, 17 input notes, 16 hidden notes and 1 output note. The training precision was 0. 005 and the final error was 0. 004 999 42 after 487 training steps. The results of forecast show that predict accuracy over 78. 62%. This method is easy to be finished with smaller error, and higher ability on circulatory system death toll on independent prediction, which can provide a new method for forecasting medical-meteorological forecast and have the value of further research.

  13. [Procedure for coding the causes of death in some circulatory system diseases].

    PubMed

    Kakorina, E P; Aleksandrova, G A; Frank, G A; Mal'kov, P G; Zaĭratians, O V; Vaĭsman, D Sh

    2014-01-01

    The paper deals with the unification of requirements for coding the causes of death in circulatory system diseases, by taking into account the recently updated ICD-10 and the Consensus of the Expert Council Task Force on Pathological Anatomy, Ministry of Health of the Russian Federation (27 February 2014).

  14. Long-term Effects of Pediatric Burns on the Circulatory System.

    PubMed

    Duke, Janine M; Randall, Sean M; Fear, Mark W; Boyd, James H; Rea, Suzanne; Wood, Fiona M

    2015-11-01

    The systemic responses to burns (in particular, elevated levels of catecholamines and stress hormones) have been shown to have an impact on cardiac function for at least 3 years in children with burns. However, it is not clear if these changes lead to long-term effects on the heart. The aim of this study was to assess whether pediatric burn injury is associated with increased long-term hospital use for circulatory diseases. A population-based longitudinal study was undertaken using linked hospital and death data from Western Australia for children younger than 15 years when hospitalized for a first burn injury (n = 10 436) in 1980-2012 and a frequency matched noninjury comparison cohort, randomly selected from Western Australia's birth registrations (n = 40 819). Crude admission rates and cumulative length of stay for circulatory diseases were calculated. Negative binomial and Cox proportional hazards regression modeling were used to generate incidence rate ratios and hazard ratios, respectively. After adjustment for demographic factors and preexisting health status, the burn cohort had 1.33 (incidence rate ratio) times (95% confidence interval [CI]: 1.08-1.64) as many circulatory system hospitalizations, 2.26 times the number of days in hospital with a diagnosis of a circulatory disease (2.26, 95% CI: 1.06-4.81), and were at a higher risk of incident admissions (hazard ratio 1.22, 95% CI: 1.03-1.46), compared with the uninjured cohort. Children who sustain burn injury experience elevated hospital admission rates and increased length of hospital stay for diseases of the circulatory system for a prolonged period of time after burn discharge. Copyright © 2015 by the American Academy of Pediatrics.

  15. Direct comparison of percutaneous circulatory support systems in specific hemodynamic conditions in a porcine model.

    PubMed

    Ostadal, Petr; Mlcek, Mikulas; Holy, Frantisek; Horakova, Svatava; Kralovec, Stepan; Skoda, Jan; Petru, Jan; Kruger, Andreas; Hrachovina, Vladimir; Svoboda, Tomas; Kittnar, Otomar; Reddy, Vivek Y; Neuzil, Petr

    2012-12-01

    Several percutaneous circulatory support systems have been recently introduced into clinical practice for the treatment of cardiogenic shock or refractory nontolerated ventricular tachycardia, in support of high-risk catheter interventions and, occasionally, cardiopulmonary resuscitation. To date, however, a direct comparison of the available systems has not been performed. Adult female pigs (weight 50-60 kg) were used throughout the experiment. Under deep anesthesia and mechanical ventilation, 3 percutaneous circulatory support systems were compared: (1) right atrium-aorta, extracorporeal membrane oxygenation (n=4); (2) left atrium-aorta, TandemHeart system (n=4); (3) left ventricle-aorta, Impella 2.5 system (n=4), and (4) left ventricle-aorta with norepinephrine at 0.1 µg/kg per minute (n=4). Hemodynamic efficacy (mean arterial pressure) was measured at 3 specific conditions: ventricular pacing at 200 and 300 beats per minute, and ventricular fibrillation. Although no or only nonsignificant differences were found among the systems at ventricular pacing of 200 and 300 beats per minute, under ventricular fibrillation, the right atrium-aorta system was significantly the most efficacious, followed by the left atrium-aorta system and the left ventricle-aorta system (P<0.001). However, the left ventricle-aorta system with norepinephrine still maintained mean arterial pressure comparable with the left atrium-aorta system. Differences were seen in the hemodynamic efficacy of available percutaneous circulatory support systems, particularly under the most severe hemodynamic condition, ventricular fibrillation.

  16. [The treatment of patients with circulatory system pathology in health resorts "Tarkhovskiĭ" and "Priozerskiĭ"].

    PubMed

    Iaremko, V I; Nikitin, E A; Ermakov, R A

    2015-02-01

    The authors showed the history of foundation and development of health resorts "Tarkhovsky" and "Priozersky", as well as an analysis of the treatment of patients with circulatory system diseases in these health resorts. It was found that the structure of patients fitted the profile of health resorts and in recent years has remained stable. Patients with circulatory system diseases accounted for 47.8%. The existing system of medical rehabilitation and restorative treatment of patients with diseases of the circulatory system in the health resorts "Tarkhovsky" and "Priozersky" ensures the implementation in full rehabilitation and recovery programs for all categories of contingent attached.

  17. A coupled biventricular finite element and lumped-parameter circulatory system model of heart failure.

    PubMed

    Wenk, Jonathan F; Ge, Liang; Zhang, Zhihong; Soleimani, Mehrdad; Potter, D Dean; Wallace, Arthur W; Tseng, Elaine; Ratcliffe, Mark B; Guccione, Julius M

    2013-01-01

    Numerical modelling of the cardiovascular system is becoming an important tool for assessing the influence of heart disease and treatment therapies. In the current study, we present an approach for modelling the interaction between the heart and the circulatory system. This was accomplished by creating animal-specific biventricular finite element (FE) models, which characterise the mechanical response of the heart, and by coupling them to a lumped-parameter model that represents the systemic and pulmonic circulatory system. In order to minimise computation time, the coupling was enforced in a weak (one-way) manner, where the ventricular pressure-volume relationships were generated by the FE models and then passed into the circulatory system model to ensure volume conservation and physiological pressure changes. The models were first validated by tuning the parameters, such that the output of the models matched experimentally measured pressures and volumes. Then the models were used to examine cardiac function and the myofibre stress in a healthy canine heart and a canine heart with dilated cardiomyopathy. The results showed good agreement with experimental measurements. The stress in the case of cardiomyopathy was found to increase significantly, while the pump function was decreased, compared to the healthy case. The total runtime of the simulations is lesser than that of many fully coupled models presented in the literature. This will allow for a much quicker evaluation of possible treatment strategies for combating the effects of heart failure, especially in optimisation schemes that require numerous FE simulations.

  18. Favorable Circulatory System Outcomes as Adjuvant Traditional Chinese Medicine (TCM) Treatment for Cerebrovascular Diseases in Taiwan

    PubMed Central

    Chiu, Hsienhsueh Elley; Hong, Yu-Chiang; Chang, Ku-Chou; Shih, Chun-Chuan; Hung, Jen-Wen; Liu, Chia-Wei; Tan, Teng-Yeow; Huang, Chih-Cheng

    2014-01-01

    Abstract Background This study searches the National Health Insurance Research Database (NHIRD) used in a previous project, aiming for reconstructing possible cerebrovascular disease-related groups (DRG),and estimating the costs between cerebrovascular disease and related diseases. Methods and Materials We conducted a nationwide retrospective cohort study in stroke inpatients, we examined the overall costs in 3 municipalities in Taiwan, by evaluating the possible costs of the expecting diagnosis related group (DRG) by using the international classification of diseases version-9 (ICD-9) system, and the overall analysis of the re-admission population that received traditional Chinese medicine (TCM) treatment and those who did not. Results The trend demonstrated that the non-participant costs were consistent with the ICD-9 categories (430 to 437) because similarities existed between years 2006 to 2007. Among the TCM patients, a wide variation and additional costs were found compared to non-TCM patients during these 2 years. The average re-admission duration was significantly shorter for TCM patients, especially those initially diagnosed with ICD 434 during the first admission. In addition, TCM patients demonstrated more severe general symptoms, which incurred high conventional treatment costs, and could result in re-admission for numerous reasons. However, in Disease 7 of ICD-9 category, representing the circulatory system was most prevalent in non-TCM inpatients, which was the leading cause of re-admission. Conclusion We concluded that favorable circulatory system outcomes were in adjuvant TCM treatment inpatients, there were less re-admission for circulatory system events and a two-third reduction of re-admission within ICD-9 code 430 to 437, compared to non-TCM ones. However, there were shorter re-admission duration other than circulatory system events by means of unfavorable baseline condition. PMID:24475108

  19. Favorable circulatory system outcomes as adjuvant traditional Chinese medicine (TCM) treatment for cerebrovascular diseases in Taiwan.

    PubMed

    Chiu, Hsienhsueh Elley; Hung, Yu-Chiang; Hong, Yu-Chiang; Chang, Ku-Chou; Shih, Chun-Chuan; Hung, Jen-Wen; Liu, Chia-Wei; Tan, Teng-Yeow; Huang, Chih-Cheng

    2014-01-01

    This study searches the National Health Insurance Research Database (NHIRD) used in a previous project, aiming for reconstructing possible cerebrovascular disease-related groups (DRG),and estimating the costs between cerebrovascular disease and related diseases. We conducted a nationwide retrospective cohort study in stroke inpatients, we examined the overall costs in 3 municipalities in Taiwan, by evaluating the possible costs of the expecting diagnosis related group (DRG) by using the international classification of diseases version-9 (ICD-9) system, and the overall analysis of the re-admission population that received traditional Chinese medicine (TCM) treatment and those who did not. The trend demonstrated that the non-participant costs were consistent with the ICD-9 categories (430 to 437) because similarities existed between years 2006 to 2007. Among the TCM patients, a wide variation and additional costs were found compared to non-TCM patients during these 2 years. The average re-admission duration was significantly shorter for TCM patients, especially those initially diagnosed with ICD 434 during the first admission. In addition, TCM patients demonstrated more severe general symptoms, which incurred high conventional treatment costs, and could result in re-admission for numerous reasons. However, in Disease 7 of ICD-9 category, representing the circulatory system was most prevalent in non-TCM inpatients, which was the leading cause of re-admission. We concluded that favorable circulatory system outcomes were in adjuvant TCM treatment inpatients, there were less re-admission for circulatory system events and a two-third reduction of re-admission within ICD-9 code 430 to 437, compared to non-TCM ones. However, there were shorter re-admission duration other than circulatory system events by means of unfavorable baseline condition.

  20. Toward a Theory of the Primo Vascular System: A Hypothetical Circulatory System at the Subcellular Level

    PubMed Central

    Lee, Byung-Cheon; Park, Sang Hyun; Yoon, Seung Zhoo

    2013-01-01

    This paper suggests a theoretical framework for the primo vascular system (PVS), a hypothetical circulatory system, in which extracellular DNA microvesicles interact to form and break down cell structures. Since Bonghan Kim reported the existence of Bonghan ducts and the SNU research team reinvestigated and named it the PVS, there has been series of studies trying to examine its structure and functions. In this paper, we hypothesize that the PVS is the network system in which extracellular DNA microvesicles circulate and interact at the subcellular level, forming and breaking down cell structures. This idea integrates A. Béchamp's idea of microzymas and Bonghan Kim's idea of sanals. A proof of this idea may complement modern medical theory, perhaps providing an essential clue for an alternative solution dealing with modern healthcare problem. PMID:23853665

  1. Toward a theory of the primo vascular system: a hypothetical circulatory system at the subcellular level.

    PubMed

    Lee, Byung-Cheon; Yoon, Ji Woong; Park, Sang Hyun; Yoon, Seung Zhoo

    2013-01-01

    This paper suggests a theoretical framework for the primo vascular system (PVS), a hypothetical circulatory system, in which extracellular DNA microvesicles interact to form and break down cell structures. Since Bonghan Kim reported the existence of Bonghan ducts and the SNU research team reinvestigated and named it the PVS, there has been series of studies trying to examine its structure and functions. In this paper, we hypothesize that the PVS is the network system in which extracellular DNA microvesicles circulate and interact at the subcellular level, forming and breaking down cell structures. This idea integrates A. Béchamp's idea of microzymas and Bonghan Kim's idea of sanals. A proof of this idea may complement modern medical theory, perhaps providing an essential clue for an alternative solution dealing with modern healthcare problem.

  2. Global solution to a hyperbolic problem arising in the modeling of blood flow in circulatory systems

    NASA Astrophysics Data System (ADS)

    Ruan, Weihua; Clark, M. E.; Zhao, Meide; Curcio, Anthony

    2007-07-01

    This paper considers a system of first-order, hyperbolic, partial differential equations in the domain of a one-dimensional network. The system models the blood flow in human circulatory systems as an initial-boundary-value problem with boundary conditions of either algebraic or differential type. The differential equations are nonhomogeneous with frictional damping terms and the state variables are coupled at internal junctions. The existence and uniqueness of the local classical solution have been established in our earlier work [W. Ruan, M.E. Clark, M. Zhao, A. Curcio, A hyperbolic system of equations of blood flow in an arterial network, J. Appl. Math. 64 (2) (2003) 637-667; W. Ruan, M.E. Clark, M. Zhao, A. Curcio, Blood flow in a network, Nonlinear Anal. Real World Appl. 5 (2004) 463-485; W. Ruan, M.E. Clark, M. Zhao, A. Curcio, A quasilinear hyperbolic system that models blood flow in a network, in: Charles V. Benton (Ed.), Focus on Mathematical Physics Research, Nova Science Publishers, Inc., New York, 2004, pp. 203-230]. This paper continues the analysis and gives sufficient conditions for the global existence of the classical solution. We prove that the solution exists globally if the boundary data satisfy the dissipative condition (2.3) or (3.2), and the norms of the initial and forcing functions in a certain Sobolev space are sufficiently small. This is only the first step toward establishing the global existence of the solution to physiologically realistic models, because, in general, the chosen dissipative conditions (2.3) and (3.2) do not appear to hold for the originally proposed boundary conditions (1.3)-(1.12).

  3. Miniature circulatory systems: A new exposure system for ecotoxicological effect assessments in riverine organisms.

    PubMed

    Feiner, Mona; Beggel, Sebastian; Geist, Juergen

    2016-11-01

    Long-term effect assessments in ecotoxicological investigations are important, yet there is a lack of suitable exposure systems for these experiments that can be used for riverine species. A cost-efficient miniature circulatory system was developed that was evaluated for its applicability in long-term exposures in 2 stream-dwelling species: brown trout (Salmo trutta) and an amphipod (Gammarus roeseli). In an egg-to-fry exposure of S. trutta, the toxicity of 2 reverse osmosis concentrates was investigated as examples. Control hatching rate of yolk sac fry was 75 ± 7% and thus complies with the Organisation for Economic Co-operation and Development validity criterion (≥66%). The reverse osmosis concentrates did not impair the hatching rate in any tested concentration. In G. roeseli, mortality rates remained below 20% during a 21-d cultivation, fulfilling the common validity criterion in ecotoxicological testing. Mortality was significantly lower when the species was fed with conditioned alder leaves instead of an artificial shrimp food. Finally, a toxicity test on G. roeseli using copper as the test substance revealed median lethal concentration (LC50) values of 156 μg/L after 96 h and 99 μg/L after 264 h, which is in line with literature findings using other accepted exposure units. In conclusion, the miniature circulatory system provides a novel and cost-efficient exposure system for long-term investigations on riverine species that may also be applicable for other species of fishes and macroinvertebrates. Environ Toxicol Chem 2016;35:2827-2833. © 2016 SETAC. © 2016 SETAC.

  4. Disparity in regional and systemic circulatory capacities: do they affect the regulation of the circulation?

    PubMed Central

    Calbet, J. A. L.; Joyner, M. J.

    2010-01-01

    In this review we integrate ideas about regional and systemic circulatory capacities and the balance between skeletal muscle blood flow and cardiac output during heavy exercise in humans. In the first part of the review we discuss issues related to the pumping capacity of the heart and the vasodilator capacity of skeletal muscle. The issue is that skeletal muscle has a vast capacity to vasodilate during exercise [~300 mL (100 g)−1 min−1], but the pumping capacity of the human heart is limited to 20–25 L min−1 in untrained subjects and ~35 L min−1 in elite endurance athletes. This means that when more than 7–10 kg of muscle is active during heavy exercise, perfusion of the contracting muscles must be limited or mean arterial pressure will fall. In the second part of the review we emphasize that there is an interplay between sympathetic vasoconstriction and metabolic vasodilation that limits blood flow to contracting muscles to maintain mean arterial pressure. Vasoconstriction in larger vessels continues while constriction in smaller vessels is blunted permitting total muscle blood flow to be limited but distributed more optimally. This interplay between sympathetic constriction and metabolic dilation during heavy whole-body exercise is likely responsible for the very high levels of oxygen extraction seen in contracting skeletal muscle. It also explains why infusing vasodilators in the contracting muscles does not increase oxygen uptake in the muscle. Finally, when ~80% of cardiac output is directed towards contracting skeletal muscle modest vasoconstriction in the active muscles can evoke marked changes in arterial pressure. PMID:20345408

  5. Disparity in regional and systemic circulatory capacities: do they affect the regulation of the circulation?

    PubMed

    Calbet, J A L; Joyner, M J

    2010-08-01

    In this review we integrate ideas about regional and systemic circulatory capacities and the balance between skeletal muscle blood flow and cardiac output during heavy exercise in humans. In the first part of the review we discuss issues related to the pumping capacity of the heart and the vasodilator capacity of skeletal muscle. The issue is that skeletal muscle has a vast capacity to vasodilate during exercise [approximately 300 mL (100 g)(-1) min(-1)], but the pumping capacity of the human heart is limited to 20-25 L min(-1) in untrained subjects and approximately 35 L min(-1) in elite endurance athletes. This means that when more than 7-10 kg of muscle is active during heavy exercise, perfusion of the contracting muscles must be limited or mean arterial pressure will fall. In the second part of the review we emphasize that there is an interplay between sympathetic vasoconstriction and metabolic vasodilation that limits blood flow to contracting muscles to maintain mean arterial pressure. Vasoconstriction in larger vessels continues while constriction in smaller vessels is blunted permitting total muscle blood flow to be limited but distributed more optimally. This interplay between sympathetic constriction and metabolic dilation during heavy whole-body exercise is likely responsible for the very high levels of oxygen extraction seen in contracting skeletal muscle. It also explains why infusing vasodilators in the contracting muscles does not increase oxygen uptake in the muscle. Finally, when approximately 80% of cardiac output is directed towards contracting skeletal muscle modest vasoconstriction in the active muscles can evoke marked changes in arterial pressure.

  6. [Autonomic neuropathy--a problem of the circulatory system and digestive tract].

    PubMed

    Punkkinen, Jari; Koskenpato, Jari; Rosengård-Bärlund, Milla

    2014-01-01

    An autonomic disorder of the circulatory system becomes manifest as aberrant heart rate variability and baroreflex sensitivity already years before progressing into symptomatic disease, in which case the condition is no longer curable. Diagnosis is based on tests of autonomic nervous system function. The main thing in the treatment is management of risk factors of cardiovascular diseases in addition to enhanced glucose homeostasis. Autonomic neuropathy may also affect the digestive tract and be accompanied by esophageal motility disorder, gastroparesis, diarrhea, constipation or fecal incontinence. It is essential in the diagnosis to exclude other diseases of the digestive tract.

  7. An "ancient" complexity? Evolutionary morphology of the circulatory system in Xiphosura.

    PubMed

    Göpel, Torben; Wirkner, Christian S

    2015-08-01

    Horseshoe crabs (Xiphosura) have been an object of zoological research for almost 200 years. Although some morphological work on the circulatory system has been done, the three-dimensional structure of this complex organ system has never been shown satisfactorily and some crucial questions remain unanswered. Here, the circulatory systems of juveniles of the horseshoe crab taxa Limulus polyphemus and Carcinoscorpius rotundicauda were investigated using a combination of an injection method and micro-computed tomography. Data were processed and 3D-visualized using reconstruction software. Furthermore, the heart was examined using scanning electron microscopy. Additionally, the histology of some structures was investigated via light microscopy and transmission electron microscopy. The results show the high degree of complexity of the arterial and lacunar systems of Xiphosura and provide insights into their three-dimensional structure and relationship to other organ systems such as the central nervous system. We show that the major lacunae, previously described as vessel-like - though indeed highly ramified - can clearly be distinguished from arteries in histological sections because they have no distinct walls. Similarities and differences between the xiphosuran species and arachnids are highlighted and possible phylogenetic implications and evolutionary scenarios discussed. Copyright © 2015 Elsevier GmbH. All rights reserved.

  8. Circulatory assistance in small infants and neonates with a hydraulically driven system: a viable option?

    PubMed

    Reiss, Nils; Körfer, Reiner

    2007-01-01

    We have developed a new drive system for a cardiac assist system for use with newborns and infants. This study reports results of animal experiments in which this system was tested using a commercially available 25-ml ventricle. A major property of the device is its hydraulic mode, which allows not only for the conventional full-empty mode (chamber completely filled in diastole) but also for the filled-empty mode, in which the chamber is completely emptied in systole but only partially filled in systole; this mode gives full flexibility to adjust the pump frequency for any given pump flow rate. The assist device was applied in eight pigs (weight 9-14 kg) for left ventricular assistance during normal and impaired cardiac function (pacing-induced cardiac shock, mean arterial blood pressure less than 40 mmHg). Both, full-empty and filled-empty mode during normal cardiac function led to significantly decreased pulmonary capillary wedge pressure, suggesting load reduction of the right ventricle. In impaired cardiac function, circulatory assistance increased the diminished cardiac output and systolic arterial blood pressure, although only the latter was statistically significant. Neither arterial lactate concentration nor oxygen uptake was reduced during circulatory assistance for normal and impaired cardiac function. These results suggest that the cardiac ventricular assist device can be used as an effective circulatory assist device and that the function of the newly introduced filled-empty mode, which allows for a high degree of functional flexibility, is not inferior to that of the classical, but less flexible, full-empty mode.

  9. Burden of Circulatory System Diseases and Ignored Barriers of Knowledge Translation

    PubMed Central

    Ghafouri, Hamed-Basir; Saravani, Shahzad; Shokraneh, Farhad

    2012-01-01

    Circulatory system disease raise third highest disability-adjusted life years among Iranians and ischemic cardiac diseases are main causes for such burden. Despite available evidences on risk factors of the disease, no effective intervention was implemented to control and prevent the disease. This paper non-systematically reviews available literature on the problem, solutions, and barriers of implementation of knowledge translation in Iran. It seems that there are ignored factors such as cultural and motivational issues in knowledge translation interventions but there are hopes for implementation of started projects and preparation of students as next generation of knowledge transferors. PMID:24250994

  10. Perturbation analysis of internal balancing for lightly damped mechanical systems with gyroscopic and circulatory forces

    NASA Technical Reports Server (NTRS)

    Blelloch, P. A.; Mingori, D. L.; Wei, J. D.

    1987-01-01

    Approximate expressions are developed for internally balanced singular values corresponding to the modes of mechanical systems with gyroscopic forces, light damping, and small circulatory forces. A brief overview is first given of the balanced realization model reduction method, including a discussion of recent work. The models considered are defined, and a perturbation analysis is used to show that the modal representation becomes asymptotically balanced as damping reduces to zero. The approximate balanced singular values are calculated, and a simple example of a flexible, dual-spin spacecraft is given as an illustration of the results.

  11. AB-180 circulatory support system: summary of development and phase I clinical trial.

    PubMed

    Griffin, W P; Savage, E B; Clark, R E; Pacella, J J; Johnson, G A; Magovern, J A; Magovern, G J

    1998-01-01

    The AB-180 Circulatory Support System (AB-180 CSS; Cardiac Assist Technologies, Pittsburgh, PA) is a left ventricular assist system for investigational use in patients with postcardiotomy cardiogenic shock who are refractory to standard treatment with an intra-aortic balloon pump, pharmacologic treatment, or both. The intent of the AB-180 CSS is to provide temporary (up to 14 days) mechanical circulatory support until the heart recovers adequate mechanical function. The system consists of a small implantable centrifugal pump and a controller. A unique infusion system produces a hydrodynamic bearing between rotational and stationary components of the AB-180 CSS pump. This infusion system also provides a source of heparin for localized anticoagulation. Extensive bench and animal work has illustrated anticoagulation requirements, established operating guidelines, and demonstrated safety and efficacy. An investigational device exemption has been granted for a Phase I, five patient feasibility study at Allegheny General Hospital in Pittsburgh, Pennsylvania. To date, the pump has been implanted in one patient. The results from this first case are presented here.

  12. Noninvasive optoacoustic system for rapid diagnosis and management of circulatory shock

    NASA Astrophysics Data System (ADS)

    Petrov, Irene Y.; Kinsky, Michael; Petrov, Yuriy; Petrov, Andrey; Henkel, S. N.; Seeton, Roger; Esenaliev, Rinat O.; Prough, Donald S.

    2013-03-01

    Circulatory shock can lead to death or severe complications, if not promptly diagnosed and effectively treated. Typically, diagnosis and management of circulatory shock are guided by blood pressure and heart rate. However, these variables have poor specificity, sensitivity, and predictive value. Early goal-directed therapy in septic shock patients, using central venous catheterization (CVC), reduced mortality from 46.5% to 30%. However, CVC is invasive and complication-prone. We proposed to use an optoacoustic technique for noninvasive, rapid assessment of peripheral and central venous oxygenation. In this work we used a medical grade optoacoustic system for noninvasive, ultrasound image-guided measurement of central and peripheral venous oxygenation. Venous oxygenation during shock declines more rapidly in the periphery than centrally. Ultrasound imaging of the axillary [peripheral] and internal jugular vein [central] was performed using the Vivid e (GE Healthcare). We built an optoacoustic interface incorporating an optoacoustic transducer and a standard ultrasound imaging probe. Central and peripheral venous oxygenations were measured continuously in healthy volunteers. To simulate shock-induced changes in central and peripheral oxygenation, we induced peripheral vasoconstriction in the upper extremity by using a cooling blanket. Central and peripheral venous oxygenations were measured before (baseline) and after cooling and after rewarming. During the entire experiment, central venous oxygenation was relatively stable, while peripheral venous oxygenation decreased by 5-10% due to cooling and recovered after rewarming. The obtained data indicate that noninvasive, optoacoustic measurements of central and peripheral venous oxygenation may be used for diagnosis and management of circulatory shock with high sensitivity and specificity.

  13. [Comparison of a rural town and a fishing town: diet and circulatory system diseases].

    PubMed

    Liang, H; Ozasa, K; Higashi, A; Watanabe, Y; Hayashi, K; Aoike, A; Kawai, K

    1993-10-01

    We report a comparative study of the Standardized Mortality Ratio (SMR) for circulatory system diseases and diet in a rural town and a fishing town in Kyoto Prefecture. SMR was assessed during the 5-year period from 1983 through 1987, and compared with the standard age- and sex-adjusted demographic and mortality statistics compiled by the National Census Bureau of Japan in 1985. A food frequency questionnaire in which the respondents evaluated their food consumption during the previous 1-year period was used to assess diet. The questionnaire was administered during February 1989 in the rural town and during February 1990 in the fishing town. In comparison with the standard statistics, SMR was higher in the rural town and lower in the fishing town. The inhabitants of the fishing town more frequently consumed low-fat and low-sodium foods, such as fish, potatoes, tofu, and green, yellow and other vegetables, and less frequently consumed high-fat and high-sodium foods, such as meat, fried food, pickles, than did the inhabitants of the rural town. The residents of the fishing town also consumed a greater variety of foods in one week. The two towns differ in geography and economic structure, and their inhabitants have different life-styles and eating habits. The lower SMR for circulatory system diseases in the fishing town may be related to the greater consumption of fish and vegetables with lower meat and salt intake, as well as the balanced of diet.

  14. Transcutaneous energy transmission for mechanical circulatory support systems: history, current status, and future prospects.

    PubMed

    Slaughter, Mark S; Myers, Timothy J

    2010-07-01

    A totally implantable mechanical circulatory support system would be very desirable for destination therapy. However, implanting all components of a pulsatile total artificial heart (TAH) or left ventricular assist device (LVAD) is complex because of the requirement for a continuous electrical power supply and the need for volume compensation. Implantable compliance chambers were developed for early LVAD designs, and although they functioned properly during initial laboratory tests, air loss by diffusion and the development of fibrous tissue around the sac eventually rendered them ineffective. Because these problems have not yet been overcome, volume displacement LVADs are currently designed with either a direct communication to an external drive console or an atmospheric vent. Transcutaneous energy transmission systems (TETSs) were also developed, but because the skin was being penetrated for volume compensation, it seemed more efficient to transmit electrical power through wires incorporated into the venting apparatus. More recently, TETSs were used clinically for both a pulsatile TAH and LVAD in a small number of patients, but for reasons unrelated to the TETS, neither of these devices is presently in use. Because the newer continuous-flow LVADs do not require a compliance chamber, they present a potential future application for TETS technology, because infections of the percutaneous tube continue to be one of the most important limitations of long-term circulatory support. A totally implantable LVAD with an incorporated TETS for destination therapy could become an important advance in the treatment of end-stage heart failure.

  15. Development of the Baylor-Nikkiso centrifugal pump with a purging system for circulatory support.

    PubMed

    Naito, K; Miyazoe, Y; Aizawa, T; Mizuguchi, K; Tasai, K; Ohara, Y; Orime, Y; Glueck, J; Takatani, S; Noon, G P

    1993-07-01

    The Baylor-Nikkiso centrifugal pump is a magnetically coupled system with a V-ring seal separating the pump and the actuator chamber. To prevent thrombus formation behind the impeller and to extend the life of the pump to 2 weeks of continuous operation, we incorporated a purging chamber behind the V-ring seal. An external pump connected to this purging chamber infused fluid at a constant rate to wash the shaft-seal area. To evaluate the effectiveness of the purging system, we have carried out biventricular bypass experiments using calves. The purging system was successful in reducing the level of thrombus formation after 2 weeks of operation. The results of these studies confirmed that the Baylor-Nikkiso centrifugal pump with this purging system is suitable for at least 2 weeks of continuous operation as a circulatory support system.

  16. Quantitative Circulatory Physiology: an integrative mathematical model of human physiology for medical education.

    PubMed

    Abram, Sean R; Hodnett, Benjamin L; Summers, Richard L; Coleman, Thomas G; Hester, Robert L

    2007-06-01

    We have developed Quantitative Circulatory Physiology (QCP), a mathematical model of integrative human physiology containing over 4,000 variables of biological interactions. This model provides a teaching environment that mimics clinical problems encountered in the practice of medicine. The model structure is based on documented physiological responses within peer-reviewed literature and serves as a dynamic compendium of physiological knowledge. The model is solved using a desktop, Windows-based program, allowing students to calculate time-dependent solutions and interactively alter over 750 parameters that modify physiological function. The model can be used to understand proposed mechanisms of physiological function and the interactions among physiological variables that may not be otherwise intuitively evident. In addition to open-ended or unstructured simulations, we have developed 30 physiological simulations, including heart failure, anemia, diabetes, and hemorrhage. Additional stimulations include 29 patients in which students are challenged to diagnose the pathophysiology based on their understanding of integrative physiology. In summary, QCP allows students to examine, integrate, and understand a host of physiological factors without causing harm to patients. This model is available as a free download for Windows computers at http://physiology.umc.edu/themodelingworkshop.

  17. Laguerre-model blind system identification: cardiovascular dynamics estimated from multiple peripheral circulatory signals.

    PubMed

    McCombie, Devin B; Reisner, Andrew T; Asada, Haruhiko Harry

    2005-11-01

    This paper presents a method for comparing multiple circulatory waveforms measured at different locations to improve cardiovascular parameter estimation from these signals. The method identifies the distinct vascular dynamics that shape each waveform signal, and estimates the common cardiac flow input shared by them. This signal-processing algorithm uses the Laguerre function series expansion for modeling the hemodynamics of each arterial branch, and identifies unknown parameters in these models from peripheral waveforms using multichannel blind system identification. An effective technique for determining the Laguerre base pole is developed, so that the Laguerre expansion captures and quickly converges to the intrinsic arterial dynamics observed in the two circulatory signals. Furthermore, a novel deconvolution method is developed in order to stably invert the identified dynamic models for estimating the cardiac output (CO) waveform from peripheral pressure waveforms. The method is applied to experimental swine data. A mean error of less than 5% with the measured peripheral pressure waveforms has been achieved using the models and excellent agreement between the estimated CO waveforms and the gold standard measurements have been obtained.

  18. von Hippel-Lindau protein regulates transition from the fetal to the adult circulatory system in retina.

    PubMed

    Kurihara, Toshihide; Kubota, Yoshiaki; Ozawa, Yoko; Takubo, Keiyo; Noda, Kousuke; Simon, M Celeste; Johnson, Randall S; Suematsu, Makoto; Tsubota, Kazuo; Ishida, Susumu; Goda, Nobuhito; Suda, Toshio; Okano, Hideyuki

    2010-05-01

    In early neonates, the fetal circulatory system undergoes dramatic transition to the adult circulatory system. Normally, embryonic connecting vessels, such as the ductus arteriosus and the foramen ovale, close and regress. In the neonatal retina, hyaloid vessels maintaining blood flow in the embryonic retina regress, and retinal vessels take over to form the adult-type circulatory system. This process is regulated by a programmed cell death switch mediated by macrophages via Wnt and angiopoietin 2 pathways. In this study, we seek other mechanisms that regulate this process, and focus on the dramatic change in oxygen environment at the point of birth. The von Hippel-Lindau tumor suppressor protein (pVHL) is a substrate recognition component of an E3-ubiquitin ligase that rapidly destabilizes hypoxia-inducible factor alphas (HIF-alphas) under normoxic, but not hypoxic, conditions. To examine the role of oxygen-sensing mechanisms in retinal circulatory system transition, we generated retina-specific conditional-knockout mice for VHL (Vhl(alpha)(-CreKO) mice). These mice exhibit arrested transition from the fetal to the adult circulatory system, persistence of hyaloid vessels and poorly formed retinal vessels. These defects are suppressed by intraocular injection of FLT1-Fc protein [a vascular endothelial growth factor (VEGF) receptor-1 (FLT1)/Fc chimeric protein that can bind VEGF and inhibit its activity], or by inactivating the HIF-1alpha gene. Our results suggest that not only macrophages but also tissue oxygen-sensing mechanisms regulate the transition from the fetal to the adult circulatory system in the retina.

  19. A Mock Circulatory System Incorporating a Compliant 3D-Printed Anatomical Model to Investigate Pulmonary Hemodynamics.

    PubMed

    Knoops, Paul G M; Biglino, Giovanni; Hughes, Alun D; Parker, Kim H; Xu, Linzhang; Schievano, Silvia; Torii, Ryo

    2017-07-01

    A realistic mock circulatory system (MCS) could be a valuable in vitro testbed to study human circulatory hemodynamics. The objective of this study was to design a MCS replicating the pulmonary arterial circulation, incorporating an anatomically representative arterial model suitable for testing clinically relevant scenarios. A second objective of the study was to ensure the system's compatibility with magnetic resonance imaging (MRI) for additional measurements. A latex pulmonary arterial model with two generations of bifurcations was manufactured starting from a 3D-printed mold reconstructed from patient data. The model was incorporated into a MCS for in vitro hydrodynamic measurements. The setup was tested under physiological pulsatile flow conditions and results were evaluated using wave intensity analysis (WIA) to investigate waves traveling in the arterial system. Increased pulmonary vascular resistance (IPVR) was simulated as an example of one pathological scenario. Flow split between right and left pulmonary artery was found to be realistic (54 and 46%, respectively). No substantial difference in pressure waveform was observed throughout the various generations of bifurcations. Based on WIA, three main waves were identified in the main pulmonary artery (MPA), that is, forward compression wave, backward compression wave, and forward expansion wave. For IPVR, a rise in mean pressure was recorded in the MPA, within the clinical range of pulmonary arterial hypertension. The feasibility of using the MCS in the MRI scanner was demonstrated with the MCS running 2 h consecutively while acquiring preliminary MRI data. This study shows the development and verification of a pulmonary MCS, including an anatomically correct, compliant latex phantom. The setup can be useful to explore a wide range of hemodynamic questions, including the development of patient- and pathology-specific models, considering the ease and low cost of producing rapid prototyping molds, and the

  20. Non-Intrusive Device for Real-Time Circulatory System Assessment with Advanced Signal Processing Capabilities

    NASA Astrophysics Data System (ADS)

    Pinheiro, E.; Postolache, O.; Girão, P.

    2010-01-01

    This paper presents a device that uses three cardiography signals to characterize several important parameters of a subject's circulatory system. Using electrocardiogram, finger photoplethysmogram, and ballistocardiogram, three heart rate estimates are acquired from beat-to-beat time interval extraction. Furthermore, pre-ejection period, pulse transit time (PTT), and pulse arrival time (PAT) are computed, and their long-term evolution is analyzed. The system estimates heart rate variability (HRV) and blood pressure variability (BPV) from the heart rate and PAT time series, to infer the activity of the cardiac autonomic system. The software component of the device evaluates the frequency content of HRV and BPV, and also their fractal dimension and entropy, thus providing a detailed analysis of the time series' regularity and complexity evolution, to allow personalized subject evaluation.

  1. Long-term Mechanical Circulatory Support System reliability recommendation by the National Clinical Trial Initiative subcommittee.

    PubMed

    Lee, James

    2009-01-01

    The Long-Term Mechanical Circulatory Support (MCS) System Reliability Recommendation was published in the American Society for Artificial Internal Organs (ASAIO) Journal and the Annals of Thoracic Surgery in 1998. At that time, it was stated that the document would be periodically reviewed to assess its timeliness and appropriateness within 5 years. Given the wealth of clinical experience in MCS systems, a new recommendation has been drafted by consensus of a group of representatives from the medical community, academia, industry, and government. The new recommendation describes a reliability test methodology and provides detailed reliability recommendations. In addition, the new recommendation provides additional information and clinical data in appendices that are intended to assist the reliability test engineer in the development of a reliability test that is expected to give improved predictions of clinical reliability compared with past test methods. The appendices are available for download at the ASAIO journal web site at www.asaiojournal.com.

  2. Stability of circulatory elastic systems in the presence of magnetic damping.

    NASA Technical Reports Server (NTRS)

    Smith, T. E.; Herrmann, G.

    1971-01-01

    The effect of a type of magnetic damping on the stability of equilibrium of some circulatory elastic systems is examined. A simple system with two degrees of freedom is considered first, and a destabilization is found to be caused by the magnetic field. The nature of the destabilization, however, is not identical to that caused by internal viscous damping. The differences and similarities between the two effects are discussed, and the results are also compared with those of linear external viscous damping. A continuous cantilever bar subjected to a follower force at its free end is then examined. It is found that the critical load is independent of the strength of the magnetic field, and is considerably lower than the corresponding critical load in the absence of a magnetic field. Finally, the continuous cantilever is treated approximately by Galerkin's procedure and also by using a two-degree-of-freedom model of the cantilever; the results obtained are qualitatively the same.

  3. Downregulation of Clock in circulatory system leads to an enhancement of fibrinolysis in mice.

    PubMed

    Cheng, Shuting; Jiang, Zhou; Zou, Yan; Chen, Chen; Wang, Yuhui; Liu, Yanyou; Xiao, Jing; Guo, Huiling; Wang, Zhengrong

    2011-09-01

    As a main component of circadian genes, clock plays not only an important role in circadian rhythm but also in the regulation of many physiological systems. The dysfunction of clock genes is associated with the development of various disorders. Many studies have investigated the association between clock genes and blood coagulation and the fibrinolytic system. The present study was designed to investigate the effect of downregulation of circulatory Clock on blood coagulation and fibrinolysis at the initial stage of active phase in male mice. Downregulation of the expression of the Clock gene by siRNA and, subsequently, its effect on the thrombotic potential and the expression of relative coagulative and/or fibrinolytic factors were investigated. It was found that the Clock interfered mice were less liable to thrombosis and showed prolonged prothrombin time (PT) and activated partial thromboplastin time (APTT) at Zeitgeber time (ZT) 15. Meanwhile, these mice also showed an increase in factor VII (FVII) and a decrease in thrombomodulin (TM) and plasminogen activator inhibitor 1 (PAI-1) at ZT 15 at both transcriptional and translational levels. PT, APTT and mRNA expressions of fvii, tm and pai-1 were analyzed with the least-squares fit of a 24-h cosine function by single cosinor method; no circadian rhythm was determined in PT and APTT, and a higher amplitude of fvii in the Clock RNAi group was found with a circadian phase shift, while lower amplitudes of tm and pai-1 were found in the Clock RNAi group with nearly no phase shift. All these results suggest that downregulation of the Clock gene in circulatory system has an effect on factors involved in both blood coagulation and fibrinolysis resulting in an enhancement in mice. This may be considered as an indication that Clock regulates thrombotic homeostasis through the fibrinolytic system.

  4. Intraoperative circulatory management using the FloTrac™ system in laparoscopic liver resection.

    PubMed

    Kitaguchi, Kazuhiko; Gotohda, Naoto; Yamamoto, Hiroyuki; Kato, Yuichiro; Takahashi, Shinichiro; Konishi, Masaru; Hayashi, Ryuichi

    2015-05-01

    Several studies have shown that maintenance of the central venous pressure at a low level during liver surgery is effective for intraoperative management. However, others have suggested that stroke volume variation (SVV) may be a better predictor of fluid responsiveness than central venous pressure. The purpose of this study is to conduct a new type of circulatory management using the FloTrac(TM) system in laparoscopic liver resection and to evaluate specific fluctuations in SVV. Of the laparoscopic liver resections that we performed between March 2012 and December 2013, we used the FloTrac system for intraoperative circulatory management in 21 cases. We analyzed the data, mainly the average value of SVV. The average SVV value during liver transection was 5.2%-24.6% (mean, 17.0%), and 18 cases (86%) exceeded the conventional cut-off value (13%). The average SVV value was 4.3%-18.2% (mean, 9.7%) when pneumoperitoneum was not in effect, whereas it was 7.3% greater on average during liver transection (mean, 17.0%). No perioperative complications developed. The average SVV value during laparoscopic liver transection (mean, 17.0%) exceeded the conventional cut-off value, but in this study, no perioperative complications developed, which enabled safe management. We might be able to manage appropriate fluid control using FloTrac system in patients with laparoscopic liver resection. Therefore, it is necessary to set the target SVV and conduct prospective trials to verify the safety margin for intraoperative management in the future. © 2014 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and Wiley Publishing Asia Pty Ltd.

  5. [Forming a community at risk for circulatory system diseases among workers engaged into underground mining].

    PubMed

    Shliapnikov, D M; Shur, P Z; Kostarev, V G; Alexeyev, V B; Vlasova, E M; Uhabov, V M

    2015-01-01

    Forming a community at risk for circulatory system diseases will increase efficiency of medical and prophylactic measures on managing risk of arterial hypertension. Epidemiologic analysis helped to reveal reliable connection between arterial hypertension predictors and work conditions of mining machine operators and supported actualization of high occupational risk suggested in a priori evaluation. Mathematic modelling helped to forecast increase in the disease probability: with noise level of 94 dB after 10 years of work, 17.9% of workers are expected to have arterial hypertension preventing from further occupational activity. Forecasting results of arterial hypertension probability help to form risk groups for medical and preventive technologies managing occupational risk, and predictors enable to specify necessity of individual medical preventive measures.

  6. Automation of a portable extracorporeal circulatory support system with adaptive fuzzy controllers.

    PubMed

    Mendoza García, A; Krane, M; Baumgartner, B; Sprunk, N; Schreiber, U; Eichhorn, S; Lange, R; Knoll, A

    2014-08-01

    The presented work relates to the procedure followed for the automation of a portable extracorporeal circulatory support system. Such a device may help increase the chances of survival after suffering from cardiogenic shock outside the hospital, additionally a controller can provide of optimal organ perfusion, while reducing the workload of the operator. Animal experiments were carried out for the acquisition of haemodynamic behaviour of the body under extracorporeal circulation. A mathematical model was constructed based on the experimental data, including a cardiovascular model, gas exchange and the administration of medication. As the base of the controller fuzzy logic was used allowing the easy integration of knowledge from trained perfusionists, an adaptive mechanism was included to adapt to the patient's individual response. Initial simulations show the effectiveness of the controller and the improvements of perfusion after adaptation. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  7. The circulatory system: blood procurement, AIDS, and the social body in China.

    PubMed

    Erwin, Kathleen

    2006-06-01

    The market for blood thrived in China for more than a decade, preying on rural villagers desperate for cash. Profit motives and unhygienic collection created an AIDS epidemic, where now up to 80 percent of adults in some villages are HIV infected. Today, illegal blood banks continue to operate in some areas. Moreover, better screening and blood testing do little to address the underlying cultural reluctance to give blood. This article examines what is at stake for blood donors in the circulation of blood through both the physical and the social bodies in China today. I argue that public health and social policy solutions require consideration of the symbolic meanings of blood and the body, kin relations, and gift exchange. China's HIV-contaminated blood procurement crisis demands a critical reexamination of the hidden processes embedded in a "circulatory system" that has inseparably bound the "gift of life" and a "commodity of death".

  8. Effect of 5E Instructional Model in Student Success in Primary School 6th Year Circulatory System Topic

    ERIC Educational Resources Information Center

    Cardak, Osman; Dikmenli, Musa; Saritas, Ozge

    2008-01-01

    The aim of this study is to research the effect of the 5E instructional model on primary (sixth grade) student success during the circulatory system unit. This study was conducted with 38 students in two different classes by the same researcher in 2006-2007. One of the classes was assigned as the control group and the other as the experimental…

  9. [The gender aspects of diet factors effect on development of diseases of circulatory system among rural population].

    PubMed

    Kamalova, F M; Valeeva, E R

    2014-01-01

    The unhealthy diet is one of important controllable risk factors of development of noninfectious diseases. The gender differences in attitude to one's own health confirm significance of their effect on health condition. The study was carried out to establish the effect of diet factors on the rate of diseases of circulatory system in rural population with consideration of gender distribution. The analysis of results of sampling examination of rural population established that 51% of disease rate in males and 22% of disease rate in females are related to diseases of circulatory system. In males and females rate of diseases of circulatory system is determined by diet factors. The direction of relationship is direct and inverse, differs in males and females and depends on diet factors. The gender differences were manifested not only in conditionality of rate of diseases of circulatory system by diet factors but also by their mutual interaction. The health management of rural population is based on examination and analysis of relationship between health of rural population and factors of their diet.

  10. Effect of 5E Instructional Model in Student Success in Primary School 6th Year Circulatory System Topic

    ERIC Educational Resources Information Center

    Cardak, Osman; Dikmenli, Musa; Saritas, Ozge

    2008-01-01

    The aim of this study is to research the effect of the 5E instructional model on primary (sixth grade) student success during the circulatory system unit. This study was conducted with 38 students in two different classes by the same researcher in 2006-2007. One of the classes was assigned as the control group and the other as the experimental…

  11. Viscoelasticity of blood and viscoelastic blood analogues for use in polydymethylsiloxane in vitro models of the circulatory system.

    PubMed

    Campo-Deaño, Laura; Dullens, Roel P A; Aarts, Dirk G A L; Pinho, Fernando T; Oliveira, Mónica S N

    2013-01-01

    The non-Newtonian properties of blood are of great importance since they are closely related with incident cardiovascular diseases. A good understanding of the hemodynamics through the main vessels of the human circulatory system is thus fundamental in the detection and especially in the treatment of these diseases. Very often such studies take place in vitro for convenience and better flow control and these generally require blood analogue solutions that not only adequately mimic the viscoelastic properties of blood but also minimize undesirable optical distortions arising from vessel curvature that could interfere in flow visualizations or particle image velocimetry measurements. In this work, we present the viscoelastic moduli of whole human blood obtained by means of passive microrheology experiments. These results and existing shear and extensional rheological data for whole human blood in the literature enabled us to develop solutions with rheological behavior analogous to real whole blood and with a refractive index suited for PDMS (polydymethylsiloxane) micro- and milli-channels. In addition, these blood analogues can be modified in order to obtain a larger range of refractive indices from 1.38 to 1.43 to match the refractive index of several materials other than PDMS.

  12. Viscoelasticity of blood and viscoelastic blood analogues for use in polydymethylsiloxane in vitro models of the circulatory system

    PubMed Central

    Campo-Deaño, Laura; Dullens, Roel P. A.; Aarts, Dirk G. A. L.; Pinho, Fernando T.; Oliveira, Mónica S. N.

    2013-01-01

    The non-Newtonian properties of blood are of great importance since they are closely related with incident cardiovascular diseases. A good understanding of the hemodynamics through the main vessels of the human circulatory system is thus fundamental in the detection and especially in the treatment of these diseases. Very often such studies take place in vitro for convenience and better flow control and these generally require blood analogue solutions that not only adequately mimic the viscoelastic properties of blood but also minimize undesirable optical distortions arising from vessel curvature that could interfere in flow visualizations or particle image velocimetry measurements. In this work, we present the viscoelastic moduli of whole human blood obtained by means of passive microrheology experiments. These results and existing shear and extensional rheological data for whole human blood in the literature enabled us to develop solutions with rheological behavior analogous to real whole blood and with a refractive index suited for PDMS (polydymethylsiloxane) micro- and milli-channels. In addition, these blood analogues can be modified in order to obtain a larger range of refractive indices from 1.38 to 1.43 to match the refractive index of several materials other than PDMS. PMID:24404022

  13. Pumping Rate Study of a Left Ventricular Assist Device in a Mock Circulatory System.

    PubMed

    Zhuang, Xiaoqi; Yang, Ming; Xu, Liang; Ou, Wenchu; Xu, Zihao; Meng, Fan; Huang, Huan

    2016-01-01

    The aim of this work was to investigate the hemodynamic influence of the change of pump rate on the cardiovascular system with consideration of heart rate and the resonant characteristics of the arterial system when a reliable synchronous triggering source is unavailable. Hemodynamic waveforms are recorded at baseline conditions and with the pump rate of left ventricular assist device (LVAD) at 55, 60, 66, and 70 beats per minute for four test conditions in a mock circulatory system. The total input work (TIW) and energy equivalent pressure (EEP) are calculated as metrics for evaluating the hemodynamic performance within different test conditions. Experimental results show that TIW and EEP achieve their maximum values, where the pump rate is equal to the heart rate. In addition, it demonstrates that TIW and EEP are significantly affected by changing pump rate of LVAD, especially when the pump rate is closing to the natural frequency of the arterial system. When a reliable synchronous triggering source is not available for LVAD, it is suggested that selecting a pump rate equal to the resonant frequency of the arterial system could achieve better supporting effects.

  14. [Coupled evolution of digestive, respiratory, circulatory, and excretory systems: a model investigation].

    PubMed

    Menshutkin, V V; Natochin, Iu V

    2007-01-01

    A model is developed of evolution of an organism with digestive, respiratory, circulatory, and excretory systems at the single system. The model is realized on the basis of the language STELLA 8.0. A balance is found between perfection of each individual physiological system and necessary energy expenditures for survival of the organism as a whole. The model is based on a coupled development of several visceral systems. There is analyzed effect of a change of consumption of substances with food and of oxygen amount on their oxidation, a branching of blood flow to organs, specifically to kidneys, to excrete final products of metabolism from blood. The energy expenditures for circulation are believed to be proportional to blood flow in a given organ. An increase of efficiency of renal excretion from blood of final metabolic products and toxic substances has a favorable effect on inner medium and activity of each cell of an individual, but increases of the organism energy expenditures. Interrelation of these factors under conditions of adaptation to changing environmental conditions determines peculiarities of evolution of each physiological system in an individual.

  15. Development of an in-vitro circulatory system with known resistance and capacitance

    NASA Technical Reports Server (NTRS)

    Offerdahl, C. D.; Schaub, J. D.; Koenig, S. C.; Swope, R. D.; Ewert, D. L.; Convertino, V. A. (Principal Investigator)

    1996-01-01

    An in-vitro (hydrodynamic) model of the circulatory system was developed. The model consisted of a pump, compliant tubing, and valves for resistance. The model is used to simulate aortic pressure and flow. These parameters were measured using a Konigsburg Pressure transducer and a Triton ART2 flow probe. In addition, venous pressure and flow were measured on the downstream side of the resistance. The system has a known compliance and resistance. Steady and pulsatile flow tests were conducted to determine the resistance of the model. A static compliance test was used to determine the compliance of the system. The aortic pressure and flow obtained from the hydrodynamic model will be used to test the accuracy of parameter estimation models such as the 2-element and 4-element Windkessel models and the 3-element Westkessel model. Verifying analytical models used in determining total peripheral resistance (TPR) and systemic arterial compliance (SAC) is important because it provides insight into hemodynamic parameters that indicate baroreceptor responsiveness to situations such as changes in gravitational acceleration.

  16. NASA Models of Space Radiation Induced Cancer, Circulatory Disease, and Central Nervous System Effects

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Chappell, Lori J.; Kim, Myung-Hee Y.

    2013-01-01

    The risks of late effects from galactic cosmic rays (GCR) and solar particle events (SPE) are potentially a limitation to long-term space travel. The late effects of highest concern have significant lethality including cancer, effects to the central nervous system (CNS), and circulatory diseases (CD). For cancer and CD the use of age and gender specific models with uncertainty assessments based on human epidemiology data for low LET radiation combined with relative biological effectiveness factors (RBEs) and dose- and dose-rate reduction effectiveness factors (DDREF) to extrapolate these results to space radiation exposures is considered the current "state-of-the-art". The revised NASA Space Risk Model (NSRM-2014) is based on recent radio-epidemiology data for cancer and CD, however a key feature of the NSRM-2014 is the formulation of particle fluence and track structure based radiation quality factors for solid cancer and leukemia risk estimates, which are distinct from the ICRP quality factors, and shown to lead to smaller uncertainties in risk estimates. Many persons exposed to radiation on earth as well as astronauts are life-time never-smokers, which is estimated to significantly modify radiation cancer and CD risk estimates. A key feature of the NASA radiation protection model is the classification of radiation workers by smoking history in setting dose limits. Possible qualitative differences between GCR and low LET radiation increase uncertainties and are not included in previous risk estimates. Two important qualitative differences are emerging from research studies. The first is the increased lethality of tumors observed in animal models compared to low LET radiation or background tumors. The second are Non- Targeted Effects (NTE), which include bystander effects and genomic instability, which has been observed in cell and animal models of cancer risks. NTE's could lead to significant changes in RBE and DDREF estimates for GCR particles, and the potential

  17. Head capsule, chephalic central nervous system and head circulatory system of an aberrant orthopteran, Prosarthria teretrirostris (Caelifera, Hexapoda).

    PubMed

    Baum, Eileen; Hertel, Wieland; Beutel, Rolf Georg

    2007-01-01

    The head capsule, the circulatory system and the central nervous system of the head of Prosarthria teretrirostris (Proscopiidae) is described in detail, with special consideration of modifications resulting from the aberrant head shape. The transformations of the head are completely different from those found in phasmatodeans, which are also characterised by twig mimesis. The circulatory system is distinctly modified. A hitherto undescribed additional structure in the posterior head region very likely functions as a pulsatile organ. The cephalic central nervous system is strongly elongated, with changes in the position of the suboesophageal ganglion, the corpora cardiaca and the course of the nervus mandibularis. Three-dimensional reconstructions of these two organ systems in combination with the pharynx were made using Alias Maya 6.0 software. Comparisons with other representatives of Caelifera suggest a clade comprising Proscopiidae and Morabinae. The presence of a transverse muscle connecting the antennal ampullae in Prosarthria shows that this structure likely belongs to the groundplan of Orthoptera, even though it is missing in different representatives of this group. The transverse ampullary muscle is a potential synapomorphy of Orthoptera, Phasmatodea and Dictyoptera.

  18. In vitro cardiovascular system emulator (bioreactor) for the simulation of normal and diseased conditions with and without mechanical circulatory support.

    PubMed

    Ruiz, Paula; Rezaienia, Mohammad Amin; Rahideh, Akbar; Keeble, Thomas R; Rothman, Martin T; Korakianitis, Theodosios

    2013-06-01

    This article presents a new device designed to simulate in vitro flow rates, pressures, and other parameters representing normal and diseased conditions of the human cardiovascular system. Such devices are sometimes called bioreactors or "mock" simulator of cardiovascular loops (SCVLs) in literature. Most SCVLs simulate the systemic circulation only and have inherent limitations in studying the interaction of left and right sides of circulation. Those SCVLs that include both left and right sides of the circulation utilize header reservoirs simulating cycles with constant atrial pressures. The SCVL described in this article includes models for all four chambers of the heart, and the systemic and pulmonary circulation loops. Each heart chamber is accurately activated by a separate linear motor to simulate the suction and ejection stages, thus capturing important features in the perfusion waveforms. Four mechanical heart valves corresponding to mitral, pulmonary, tricuspid, and aortic are used to control the desired unidirectional flow. This SCVL can emulate different physiological and pathological conditions of the human cardiovascular system by controlling the different parameters of blood circulation through the vascular tree (mainly the resistance, compliance, and elastance of the heart chambers). In this study, four cases were simulated: healthy, congestive heart failure, left ventricular diastolic dysfunction conditions, and left ventricular dysfunction with the addition of a mechanical circulatory support (MCS) device. Hemodynamic parameters including resistance, pressure, and flow have been investigated at aortic sinus, carotid artery, and pulmonary artery, respectively. The addition of an MCS device resulted in a significant reduction in mean blood pressure and re-establishment of cardiac output. In all cases, the experimental results are compared with human physiology and numerical simulations. The results show the capability of the SCVL to replicate various

  19. 38 CFR 4.62 - Circulatory disturbances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... FOR RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.62 Circulatory disturbances. The circulatory disturbances, especially of the lower extremity following injury in the popliteal... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Circulatory...

  20. 38 CFR 4.62 - Circulatory disturbances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... FOR RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.62 Circulatory disturbances. The circulatory disturbances, especially of the lower extremity following injury in the popliteal... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Circulatory...

  1. 38 CFR 4.62 - Circulatory disturbances.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... FOR RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.62 Circulatory disturbances. The circulatory disturbances, especially of the lower extremity following injury in the popliteal... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Circulatory...

  2. 38 CFR 4.62 - Circulatory disturbances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... FOR RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.62 Circulatory disturbances. The circulatory disturbances, especially of the lower extremity following injury in the popliteal... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Circulatory...

  3. 38 CFR 4.62 - Circulatory disturbances.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... FOR RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.62 Circulatory disturbances. The circulatory disturbances, especially of the lower extremity following injury in the popliteal... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Circulatory...

  4. A hybrid mock circulatory system: development and testing of an electro-hydraulic impedance simulator.

    PubMed

    Kozarski, M; Ferrari, G; Clemente, F; Górczyńska, K; De Lazzari, C; Darowski, M; Mimmo, R; Tosti, G; Guaragno, M

    2003-01-01

    Mock circulatory systems are used to test mechanical assist devices and for training and research purposes; when compared to numerical models, however, they are not flexible enough and rather expensive. The concept of merging numerical and physical models, resulting in a hybrid one, is applied here to represent the input impedance of the systemic arterial tree, by a conventional windkessel model built out of an electro-hydraulic (E-H) impedance simulator added to a hydraulic section. This model is inserted into an open loop circuit, completed by another hybrid model representing the ventricular function. The E-H impedance simulator is essentially an electrically controlled flow source (a gear pump). Referring to the windkessel model, it is used to simulate the peripheral resistance and the hydraulic compliance, creating the desired input impedance. The data reported describe the characterisation of the E-H impedance simulator and demonstrate its behaviour when it is connected to a hybrid ventricular model. Experiments were performed under different hemodynamic conditions, including the presence of a left ventricular assist device (LVAD).

  5. [Regulative effects of Chinese herb-compound on blood rheology and circulatory system of rabbits under simulated weightlessness].

    PubMed

    Shi, Hong-zhi; Li, Yong-zhi; Shen, Xian-yun; Fan, Quan-chun; Bai, Gui-e

    2005-08-01

    To investigate effects of Chinese herb-compound on blood rheology and circulatory system of rabbits under simulated weightlessness in order to provide bases for protecting against the influence of simulated weightlessness on cardiovascular function. Rabbits were exposed to head-down tilt (HDT -20 degrees) for 9 d to simulate weightlessness. The effect of Chinese herb-compound on indices related to blood rheology, blood-fat and orthostatic tolerance in these rabbits were examined. After head-down tilt, hematocrit value and red blood cells deformability decreased significantly; cholesterol and low density lipoprotein increased markedly; plasma fibrinogen content and triglyceride showed increasing trend. Administration of the Chinese herb-compound didn't improve the blood rheology indices, but showed a trend to decrease triglyceride and to inhibit the increase of cholesterol. In the head-up tilt (HUT) plus lower body negative pressure (LBNP) experiment, orthostatic tolerance time of the rabbits in the control group decreased, and myocardial ischemic changes in ECG, such as dropped ST segment, inverse T wave, and arrhythmia were observed. While in the Chinese herb-compound group, the heart rate of the rabbits kept smooth, ischemic changes in ECG were not clear, and orthostatic tolerance time increased. The Chinese herb-compound shows an effect of preventing orthostatic tolerance from decreasing, and improves blood-fat metabolism. It regulates different human systems on the whole, and increases ability of adaptation to ill environment.

  6. Computer modeling of interactions of an electric motor, circulatory system, and rotary blood pump.

    PubMed

    Xu, L; Fu, M

    2000-01-01

    The innovative ventricular assist systems (IVAS) is the next generation ventricular assist device for use as a permanent implantable device. Its practical application depends upon control of the electric motor and interactions of the electric motor, blood pump, and circulatory system. Computer modeling and simulation are necessary to investigate and evaluate the interactions and feasibility of sophisticated control algorithms. In this paper, a computer model of the complete system, including the cardiovascular system, blood pump, and electric motor, is proposed. The model is obtained based on an electric circuit model of the cardiovascular system, a parametric model of the blood pump, and a dynamic model of the electric motor. The cardiovascular system uses nonlinear parameters to simulate the time-varying property of the ventricles, and the cannula collapse effect caused by over-pumping. The blood pump model can be obtained either from pump design data, or test data. The motor control can be operated with closed-loop regulation, depending upon physiologic requirements. Different operation modes (current or speed) of the electric motor can be simulated. The computer model is implemented using MATLAB. Various motor operation modes are simulated and their effects are evaluated. By adjusting the motor input, the pump can achieve proper output so that normal physiology can be obtained. In addition to evaluating existing operation modes and their effect on the physiologic system, the computer simulation results show that this computer model can contribute significantly to the development of new physiologic control algorithms. It is demonstrated that, using this motor-pump-physiology interaction model, development of an innovative ventricular assist system can be greatly facilitated.

  7. [Trans isomers of unsaturated fatty acids increase the risk of atherosclerosis-related circulatory system diseases].

    PubMed

    Perova, N V; Metel'skaia, V A; Boĭtsov, S A

    2013-01-01

    The paper provides a review of the literature on a relevant non-drug prevention problem, namely the negative effect of trans isomers of unsaturated fatty acids (trans-UFA) on the risk of circulatory system diseases (CSD) and other chronic noncommunicable diseases. It gives data on the specific features of the structure and ability of trans-UFA to elevate the plasma levels of atherogenic low-density lipoproteins and to lower those of non/antiatherogenic high-density lipoproteins. The natural sources of their moderate content in the animal fats from ruminants and those of their redundant content in the margarines manufactured by hydrogenation of liquid vegetable oils are described. A new technology for preparing soft margarines (spreads) is presented, which can produce fatty products that do not virtually contain trans-UFA. There is evidence that trans-UFA can considerably raise the risk of CSD and their acute complications. It is concluded that the manufacture of fatty products with low and even no trans-UFA levels should be expanded in Russia to improve its population's health.

  8. A hybrid mock circulatory system: testing a prototype under physiologic and pathological conditions.

    PubMed

    Ferrari, Gianfranco; De Lazzari, Claudio; Kozarski, Maciej; Clemente, Fabrizio; Górczyńska, Krystyna; Mimmo, Rita; Monnanni, Eliana; Tosti, Giancarlo; Guaragno, Marco

    2002-01-01

    Hydraulic models of circulation are used to test mechanical heart assist devices and for research and training purposes. However, when compared with numerical models, they are rather expensive and often not sufficiently flexible or accurate. Flexibility and accuracy can be improved by merging numerical models with physical models, thus obtaining a hybrid model where numerical and physical sections are connected by an electrohydraulic interface. This concept is applied here to represent left ventricular function. The resulting hybrid model is inserted into the existing closed loop model of circulation. The hybrid model reproduces ventricular function by a variable elastance numerical model. Its interaction with the hydraulic sections is governed by measuring left atrial and systemic arterial pressures and computing the left ventricular output flow by the resolution of the corresponding equations. This signal is used to control a flow generator reproduced by a gear pump driven by a DC motor. Results obtained under different circulatory conditions demonstrate the behavior of the ventricular model on the pressure-volume plane and report the trend of the main hemodynamic variables.

  9. Modeling oxygen and carbon dioxide transport and exchange using a closed loop circulatory system.

    PubMed

    Carlson, Brian E; Anderson, Joseph C; Raymond, Gary M; Dash, Ranjan K; Bassingthwaighte, James B

    2008-01-01

    The binding and buffering of O2 and CO2 in the blood influence their exchange in lung and tissues and their transport through the circulation. To investigate the binding and buffering effects, a model of blood-tissue gas exchange is used. The model accounts for hemoglobin saturation, the simultaneous binding of O2, CO2, H+, 2,3-DPG to hemoglobin, and temperature effects. Invertible Hill-type saturation equations facilitate rapid calculation of respiratory gas redistribution among the plasma, red blood cell and tissue that occur along the concentration gradients in the lung and in the capillary-tissue exchange regions. These equations are well-suited to analysis of transients in tissue metabolism and partial pressures of inhaled gas. The modeling illustrates that because red blood cell velocities in the flowing blood are higher than plasma velocities after a transient there can be prolonged differences between RBC and plasma oxygen partial pressures. The blood-tissue gas exchange model has been incorporated into a higher level model of the circulatory system plus pulmonary mechanics and gas exchange using the RBC and plasma equations to account for pH and CO2 buffering in the blood.

  10. Effects of one-day reperfusion after transient forebrain ischemia on circulatory system in the rat.

    PubMed

    Kravcukova, Petra; Danielisova, Viera; Nemethova, Miroslava; Burda, Jozef; Gottlieb, Miroslav

    2010-06-01

    Although ischemia/reperfusion injury remains incompletely understood, it appears that reactive oxygen species produced mainly during postischemic recirculation play a critical role. The present study examined the impact of forebrain ischemia and subsequent one-day reperfusion on several blood parameters. We determined glutamate concentration in whole blood, measured Cu/Zn- and Mn-SOD (superoxide dismutase) activity in blood cells as well as plasma, and investigated the prevalence of single and double strand breaks of lymphocyte DNA. The results of our experiment showed that the concentration of glutamic acid in whole blood was increased by about 25%. Antioxidant activity of total SOD and Cu/Zn-SOD was reduced in blood cells and plasma. Mn-SOD activity in blood cells was not affected by ischemic insult and one-day reperfusion, but we detected its significantly lower activity in samples of plasma. We observed a weakly reduced level of double and a significantly elevated level of single strand breaks of lymphocyte DNA. In conclusion, one day of recovery after the ischemic attack failed to return peripheral circulatory system to physiological conditions. Reduced antioxidant capacity in the blood and an elevated level of excitotoxic amino acid glutamate may cause lymphocyte DNA damage, and probably contribute to insufficient postischemic recovery of brain tissue.

  11. [Nursing diagnoses and outcomes related to the circulatory-system terms (ICNP®) represented in an ontology].

    PubMed

    Cubas, Marcia Regina; Brondani, Arianny Macedo; Malucelli, Andreia

    2013-10-01

    The aim of the present study was to develop titles of Nursing Diagnoses and Outcomes (ND/NO) through the relationship between the terms of the Focus axis, limited to the Circulatory System Process, and the terms of other ICNP® axes and to integrate these terms into an ontology. Titles were developed linking 17 terms of the focus axis, which were evaluated by expert nurses in five Brazilian cities. Titles whose use concordance was above 0.80 were included in the ontology. In total, 89 titles for ND/NO were supported in the literature, and 19 were not supported; 37 were assessed as eligible for use in healthcare practice and were included in the ontology. The construction of ND/NO titles based on the ICNP® and using a formal representation of knowledge is a task that requires deepening concepts used for nursing and adequate classification revisions. The elaborated titles will facilitate the composition of diagnostics that are more consistent with practice.

  12. Receptor-mediated oral delivery of a bioencapsulated green fluorescent protein expressed in transgenic chloroplasts into the mouse circulatory system

    PubMed Central

    Limaye, Arati; Koya, Vijay; Samsam, Mohtashem; Daniell, Henry

    2012-01-01

    Oral delivery of biopharmaceutical proteins expressed in plant cells should reduce their cost of production, purification, processing, cold storage, transportation, and delivery. However, poor intestinal absorption of intact proteins is a major challenge. To overcome this limitation, we investigate here the concept of receptor-mediated oral delivery of chloroplast-expressed foreign proteins. Therefore, the transmucosal carrier cholera toxin B-subunit and green fluorescent protein (CTB-GFP), separated by a furin cleavage site, was expressed via the tobacco chloroplast genome. Polymerase chain reaction (PCR) and Southern blot analyses confirmed site-specific transgene integration and homoplasmy. Immunoblot analysis and ELISA confirmed expression of monomeric and pentameric forms of CTB-GFP, up to 21.3% of total soluble proteins. An in vitro furin cleavage assay confirmed integrity of the engineered furin cleavage site, and a GM1 binding assay confirmed the functionality of CTB-GFP pentamers. Following oral administration of CTB-GFP expressing leaf material to mice, GFP was observed in the mice intestinal mucosa, liver, and spleen in fluorescence and immunohistochemical studies, while CTB remained in the intestinal cell. This report of receptor-mediated oral delivery of a foreign protein into the circulatory system opens the door for low-cost production and delivery of human therapeutic proteins. PMID:16603603

  13. Interdisciplinary studies on the development of nuclear-fueled circulatory support systems: Collaboration of industry and academe

    NASA Technical Reports Server (NTRS)

    Norman, J. C.

    1974-01-01

    The purpose of this report is to acquaint the Houston community with specific areas of available technology, both public and private, to demonstrate to industry how this technology may be acquired and put to use to provide new and useful services for man. Much of the technology utilized in the development of nuclear-fueled circulatory support systems in our laboratories has evolved from industry, NASA, and AEC; our projects involve radiation biology, thermodynamics, energy transfers, hemodynamics, hematology, pathology, and surgery.

  14. Interdisciplinary studies on the development of nuclear-fueled circulatory support systems: Collaboration of industry and academe

    NASA Technical Reports Server (NTRS)

    Norman, J. C.

    1974-01-01

    The purpose of this report is to acquaint the Houston community with specific areas of available technology, both public and private, to demonstrate to industry how this technology may be acquired and put to use to provide new and useful services for man. Much of the technology utilized in the development of nuclear-fueled circulatory support systems in our laboratories has evolved from industry, NASA, and AEC; our projects involve radiation biology, thermodynamics, energy transfers, hemodynamics, hematology, pathology, and surgery.

  15. User's instructions for the Guyton circulatory dynamics model using the Univac 1110 batch and demand processing (with graphic capabilities)

    NASA Technical Reports Server (NTRS)

    Archer, G. T.

    1974-01-01

    The model presents a systems analysis of a human circulatory regulation based almost entirely on experimental data and cumulative present knowledge of the many facets of the circulatory system. The model itself consists of eighteen different major systems that enter into circulatory control. These systems are grouped into sixteen distinct subprograms that are melded together to form the total model. The model develops circulatory and fluid regulation in a simultaneous manner. Thus, the effects of hormonal and autonomic control, electrolyte regulation, and excretory dynamics are all important and are all included in the model.

  16. Diseases of the circulatory system among adult people diagnosed with infantile autism as children: A longitudinal case control study.

    PubMed

    Mouridsen, Svend Erik; Rich, Bente; Isager, Torben

    2016-10-01

    Research dealing with adult people with autism spectrum disorders (ASD) noticeably lags behind studies of children and young individuals with ASD. The objective of this study was to compare the prevalence and types of diseases of the circulatory system in a clinical sample of 118 adult people diagnosed with infantile autism (IA) as children with 336 sex and age matched controls from the general population. All participants were screened through the nationwide Danish National Hospital Register. The average observation time of both groups was 37.2 years, and mean age at follow-up was 49.6 years. Of the 118 people with IA, 11 (9.3%) were registered with at least one disease of the circulatory system against 54 (16.1%) in the comparison group (p=0.09; OR=0.54; 95% CI 0.3-1.2). Ischemic heart diseases occurred significantly more frequently among people in the comparison group (p=0.02). It is argued that diseases of the circulatory system may be underdiagnosed in people with IA because of the difficulties they face with respect to identifying and communicating symptoms of ill health. Bearing in mind that cardiovascular disease is the primary cause of death in most developed countries, it is suggested that to prevent disease and manage health conditions, health monitoring is essential in adult people with IA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Single and combined effects of air pollutants on circulatory and respiratory system-related mortality in Belgrade, Serbia.

    PubMed

    Stojić, Svetlana Stanišić; Stanišić, Nemanja; Stojić, Andreja; Šoštarić, Andrej

    2016-01-01

    The aim of this study was to investigate the association between short- and long-term exposure to particulate matter (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and soot and mortality attributed to circulatory and respiratory diseases in Belgrade area (Serbia). The analyzed data set comprised results of regular pollutant monitoring and corresponding administrative records on frequency of daily mortality in the period 2009-2014. Nonlinear exposure-response dependencies and delayed effects of temperature were examined by means of distributed lag nonlinear models. The air pollutant loadings and circulatory system-related death rates in Belgrade area are among the highest in Europe. Data demonstrated that excess risk of death with short-term exposure to elevated concentrations of PM10, SO2, and soot was not significant, whereas marked effect size estimates for exposure over 90 d preceding mortality were found. The influence of chronic exposure was shown to be greater for respiratory than circulatory system-related mortality. When stratified by age and gender, higher risk was noted for male individuals below the age of 65 years.

  18. A LabVIEW model incorporating an open-loop arterial impedance and a closed-loop circulatory system.

    PubMed

    Cole, R T; Lucas, C L; Cascio, W E; Johnson, T A

    2005-11-01

    While numerous computer models exist for the circulatory system, many are limited in scope, contain unwanted features or incorporate complex components specific to unique experimental situations. Our purpose was to develop a basic, yet multifaceted, computer model of the left heart and systemic circulation in LabVIEW having universal appeal without sacrificing crucial physiologic features. The program we developed employs Windkessel-type impedance models in several open-loop configurations and a closed-loop model coupling a lumped impedance and ventricular pressure source. The open-loop impedance models demonstrate afterload effects on arbitrary aortic pressure/flow inputs. The closed-loop model catalogs the major circulatory waveforms with changes in afterload, preload, and left heart properties. Our model provides an avenue for expanding the use of the ventricular equations through closed-loop coupling that includes a basic coronary circuit. Tested values used for the afterload components and the effects of afterload parameter changes on various waveforms are consistent with published data. We conclude that this model offers the ability to alter several circulatory factors and digitally catalog the most salient features of the pressure/flow waveforms employing a user-friendly platform. These features make the model a useful instructional tool for students as well as a simple experimental tool for cardiovascular research.

  19. Results following implantation of mechanical circulatory support systems: The Montreal Heart Institute experience

    PubMed Central

    El-Hamamsy, Ismaïl; Jacques, Frédéric; Perrault, Louis P; Bouchard, Denis; Demers, Philippe; White, Michel; Pelletier, Guy B; Racine, Normand; Pellerin, Michel; Carrier, Michel

    2009-01-01

    BACKGROUND: Mechanical circulatory support systems (MCSS) have been available in Canada since 1986. Accepted indications include bridging to transplantation or recovery. The present study reviewed the results following MCSS implantation at the Montreal Heart Institute (Montreal, Quebec). METHODS: From September 1987 to September 2006, 43 MCSS were implanted (32 Thoratec [Thoratec Corporation, USA], nine Cardio West TAH [SynCardia Systems Inc, USA], two Novacor [World Heart Corporation, Canada]) in 43 patients (mean [± SD] age 44±13 years; range 19 to 64 years). Indications for implantation included cardiogenic shock due to ischemic (n=19), viral (n=10) or other types of cardiomyopathies (n=14). RESULTS: The mean ejection fraction before implantation was 17.6±6.5% (range 10% to 45%). Before MCSS implantation, most patients showed signs of end-organ failure, including mechanical ventilation (77%), central venous pressure higher than 16 mmHg (44%), oliguria (35%) and hepatic dysfunction (19%). The mean duration of MCSS support was 22.8±32.8 days (range one to 158 days). Survival to transplantation or recovery was 74%. Only one patient was successfully bridged to recovery. Complications were common during MCSS support. They included re-exploration for bleeding (47%), respiratory failure (44%), renal failure requiring temporary dialysis (40%), infection (33%) and neurological events (16%). Only one patient had device failure. In patients successfully bridged to transplantation, early actuarial survival (one month) following transplantation averaged 71±8% and was 57±9% at one year. CONCLUSION: MCSS support with a left ventricular assist device or a total artificial heart provides an effective means of bridging terminally ill patients to transplantation or recovery. Early survival after transplantation shows satisfactory results. However, these results come at the expense of frequent device-related complications, and device failure remains a constant threat. PMID

  20. [The influence of the length of work on the adaptation of the circulatory system of male teachers of different specialities].

    PubMed

    Kirilina, V M; Goranskiĭ, A I

    2010-01-01

    The problem of human adaptation to the social and biological conditions of the existence is placed at the center of attention of many natural and social sciences studying vital activity of a person in all forms it displays. The basis of the existence of the human population is considered to be a social and labor activity of people. Recently, the importance of researches has increased, which enables to evaluate the functional state of a person under the circumstances of adaptation to a particular occupation. These researches are the theoretical foundation to develop methods for improving the efficiency of people in many kinds of professions, and especially it is important for elderly people. The results of social and hygienic researches among the middle-aged and elderly people involved in different trades vary and are stipulated generally by the conditions of the working environment, difficulties and intensity of work processes. The study of the features of the circulatory system of a person in the process of working activities is a significant issue in physiology. It is found that the greatest changes in the functional parameters of the blood circulation are observed in young and elderly people. In the same way, it is shown that it depends on the type of adaptation, age characteristics, work experience which result in slowing down the rate of the processes of the nervous system, the regulation of blood circulation becomes inert, the level of physical health reduces, and age displacements accelerate. These changes are considered as a result of increased spending of physiological reserves of the organism in various environmental conditions.

  1. The death of the circulatory system diseases in China: provincial socioeconomic and environmental perspective.

    PubMed

    Pu, Haixia; Li, Jiatian; Wang, Pin; Cui, Linlin; Wang, Huaxin

    2017-04-01

    Few studies have explored the association between circulatory system diseases (CSDs) and provincial socioeconomic and environmental factors from spatial perspective, although large literature have focused on CSD. The numbers of death of hypertension disease (HD), ischemic heart disease (IHD), and cerebrovascular disease (CVD) are investigated, and 14 representative socioeconomic and environmental factors are collected. Stepwise regression model (SRM) and geographically weighted regression model (GWRM) are applied to determine the spatial correlation between the number of death of those diseases and selected factors. The results are the following: (1) diseases exhibit a pattern of zonal distribution. Higher HD is mostly distributed in south district, whereas higher IHD and CVD are observed in the north area. (2) SO2 emission amount (SO2 EA) is significantly positively related with HD, while coal consumption (CC) and PM2.5 are notably positively correlated with IHD and CVD. (3) A 10,000 tons increase in SO2 EA results in three increases in the numbers of death of HD. For every 100 ten thousand tons (TTTs) increase in CC, the death of IHD and CVD increases by 11.1 and 15.7, while for every 1 μg/m(3) increase in ambient PM2.5 concentration, the numbers of death of IHD and CVD increase by 34.773 and 43.222, respectively. (4) Our findings show that there exist spatial differences for SO2 EA, CC, and PM2.5 influencing HD, IHD, and CVD. This study is expected to provide a reference for HD, IHD, and CVD control in different regions.

  2. Role of Lysosomal Enzyme Release in Circulatory Shock and Critical Illness.

    DTIC Science & Technology

    1978-06-01

    association of lysosomal enzyme release and the severity of shock in the human system in states of circulatory shocl4 and conditions of critical...antereo) 6-iI SUMMARY To determine the association of lysosomal enzyme release and the severity of shock in the human system in states of circulatory...The results, however, do not show any adverse effects from the introduction of exogenous cathepsin D into the systemic circulation during hemorrhagic

  3. Quantitative evaluation for anastomotic technique of coronary artery bypass grafting by using in-vitro mock circulatory system.

    PubMed

    Park, Young Kwang; Mita, Yutaka; Oki, Eriko; Kanemitsu, Naohiko; Shiraishi, Yasuyuki; Ishii, Yousuke; Azuma, Takashi; Ochi, Masami; Umezu, Mitsuo

    2007-01-01

    This study focuses on the development of self-training system for surgical operation and quantitative evaluation of the surgical skills. Our group has developed a self-training system for anastomotic technique in Coronary Artery Bypass Grafting (CABG) to contribute the education of cardiovascular surgery without a risk to patients. The self-training system consists of following portions, 1) "YOUCAN", coronary and graft vascular silicone model, 2) "BEAT", a device, simulating stabilized myocardial surface, and 3) Quantitative evaluation system based on in vitro mock circulatory system. The coronary and graft model has been anastomosed by expert and trainee cardiac surgeon. The anastomosed model was mounted onto test section of the in vitro mock circulatory system then identical waveforms of coronary artery was applied into the inlet of an anastomosis. The energy loss was quantified as a pressure difference between proximal and distal ends of anastomosis. The energy loss was obtained as 67.3+/-1.75 mJ (trainee) and 41.3+/-3.08 mJ (registered surgeon). It was founded that average energy loss by expert surgeon was lower by 38.6% than that by trainee surgeon. The major difference among the models of expert and trainee was the Effective Orifice Area (EOA) of the anastomosis. Through the experiment, EOA was confirmed by image analysis as 2.73 mm2 for an expert against 0.534 mm2 for a trainee. In conclusion, it was suggested that the anastomotic skill among expert and trainee surgeons could be hydrodynamically differentiated by using in vitro mock circulatory system.

  4. Cancer risks in children with congenital malformations in the nervous and circulatory system-A population based cohort study.

    PubMed

    Sun, Yuelian; Overvad, Kim; Olsen, Jørn

    2014-08-01

    We estimated the age and organ-specific cancer risk for children with a congenital malformation (CM) in the nervous or in the circulatory system. We identified 1,709,456 live born singletons in Denmark between 1 January 1977 and 31 December 2007 and excluded children with chromosomal birth defects. Information on CMs was obtained from the Danish National Hospital Register. Information on cancer occurrence was obtained from the Danish Cancer Registry. We applied Cox proportional hazards regression model to estimate hazard ratios (HR) for cancer. Children entered into the CM cohort on the day of birth regardless of when the CM was diagnosed or on the day of CM diagnosis in an alternative analysis. Overall, 4484 (0.26%) and 24,643 (1.44%) children were diagnosed with a CM in the nervous and in the circulatory system, respectively. Compared with children without any CM, children with a CM in the nervous system had a 5.97 fold (95%CI [confidence interval]: 4.66-7.64) higher risk of cancer, including cancer in the central nervous system (HR=18.84, 95%CI: 12.67-28.01), in the mesothelial and soft tissue (HR=15.64, 95%CI: 7.99-30.60), in the skin (HR=4.91, 95%CI: 2.19-11.0). The associations were stronger early in life. Children with a CM in the circulatory system had a 2.64 fold (95%CI: 2.21-3.16) higher risk of cancer, including cancer in the lymphatic and haematopoietic tissues (HR=3.22, 95%CI: 2.43-4.27) and cancer in the CNS (HR=2.40, 95%CI: 1.43-4.02). Some of these associations were weaker in the alternative analysis. Children with subtypes of CM in the two systems showed a higher cancer risk. Children who were diagnosed with a CM in the nervous system had a substantially higher cancer risk especially early in life. Children diagnosed with a CM in the circulatory system had a moderately higher cancer risk. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. [THE CHARACTERISTIC OF SOMATOTYPE AND FUNCTIONAL STATE OF CIRCULATORY SYSTEM OF STUDENT YOUTH OF THE NORTHEAST OF RUSSIA].

    PubMed

    Timofeieva, A V; Klimova, T M; Mikhailova, A E; Zakharova, R N; Vinokurova, S P; Timofeiev, L F

    2015-01-01

    The article considers results of single-step study in random sampling of female students of the M.K. Ammosov north-east federal university (n=456). The study was carried out to investigate somatotype and functional state of circulatory system. The standard technique was applied to measure height, body mass, chest circumference, level of arterial pressure and rate of heart beats. The type of somatotype was established using Pignet index. The tone of vegetative system was determined using Kérdö index. The adaptation potential of circulatory system was determined using functional changes index. The results of study established that in 61% of examined female students the type of constitution corresponds to normosthenic one. The percentage of persons with asthenic and hypersthenic type of constitution amounted to 27% and 12% correspondingly. The signs of increasing oftone ofsympathetic nervous system are observed in 89% of girls. The functional condition of circulatory system is evaluated as "tension of adaptation mechanisms" that is apparently related to period of adaptation to new conditions. The prolonged preservation of such states results in exhaustion offunctional resources of organism and can promote development of diseases. In conditions of impacting of unfavorable ecological factors the deconditionning disorders can significantly contribute to health disturbances and decreasing of life quality. To preserve youth's health during period of education the comprehensive strategy is to be implemented such components as dynamic monitoring of health, organization of adequate diet, explanation of necessity of observance of sleep and rest pattern, development of conditions for active aerobic physical exertion and activities on correction of risk factors of development of diseases are to be included.

  6. Some embryological aspects of cholinergic innervation in the cardiovascular system--a close association with the subintestinal circulatory channel.

    PubMed

    Shigei, Tatsuro; Tsuru, Hiromichi; Ishikawa, Naohisa; Yoshioka, Koichi

    2010-01-01

    A series of our studies on the dog venous system revealed that cholinergic excitatory innervation was localized in a group of veins: the portal, mesenteric, and hepatic veins and the middle segment of the inferior vena cava. Our studies on pharmacological responsiveness of dog veins also revealed that they could be divided into two groups: the visceral and somatic parts, and the cholinergic excitatory innervation localized to the visceral part. Considering these results and some relevant literature, a hypothesis is proposed on the classification of muscles of the cardiovascular system and some embryological aspects of the parasympathetic cholinergic innervation in the circulatory system are discussed. The embryonic circulatory system of vertebrates can be divided into two parts: somatic and visceral. The body of an embryo is regarded as a double tube and vessels of the visceral part and the heart belong to the inner tube. The muscle of these vessels and the heart are derived from visceral mesoderm, either the coelomic epithelium or mesenchymal cells, in common with muscle of the digestive tube; and thus the parasympathetic cholinergic nerves innervating the muscle of the digestive tube also distribute to these vessels and the heart. The heart and vascular muscles in the visceral part are structures developed early in the course of evolution in invertebrates. Their primary function is to propel the body fluid, and the chief structure containing them is the subintestinal circulatory channel (ventral aorta - heart - subintestinal vein). They exhibit spontaneous, rhythmic activity, showing characteristics of a single unit muscle, and receive parasympathetic cholinergic innervation. On the other hand, the vascular muscles in the somatic part are endothelium-associated muscles developed anew in the vertebrate; do not contract spontaneously, being classified as a multiunit muscle; and lack parasympathetic cholinergic innervation.

  7. [Assessment of the Possibility of Comparing Mortality Rates from Diseases of the Circulatory System in the United States and Russia].

    PubMed

    Boytsov, S A; Andreev, E M; Samorodskaya, I V

    2017-01-01

    to compare and discuss causes of differences between standardized mortality rates (SMR) from diseases of the circulatory system (DCS) among men and women older than 50 years in Russia and USA. Data on mortality rate in the USA were taken from WHO mortality database (WHO MD), those on the USA population by 5-years age bands from Human Mortality Database (HMD). Information on mortality rates in Russia was obtained from Rosstat. In analysis we used age-adjusted death rates and SMR for DCS or ages more or equal 50 years. For standardization of mortality rates we used data of the European Standard Population 2013. By 23 3-digit codes mortality rates among men in USA were higher than in Russia (in the structure of mortality among women there were 28 such codes). Portion of such deaths in Russia in total number of DCS deaths was 6.5% both for men and women, while figures for USA were 36.8 and 40%, respectively. About 99% of differences in SMR from DCS between countries were determined by 8 and 6 groups of causes in men and women, respectively. Analysis of 4-digit ICD codes showed that almost 40% of DSC class deaths both in Russia and USA had the forth digit of ICD-10 code 8 or 9 and were accompanied by wording "other" or "unspecified" or formulation of diseases which were not used in clinical practice and were absent in both guidelines issued by Russian or American professional societies. Despite existence of ICD rules the conducted analysis allows to state that those rules could be interpreted differently in various countries. This resulted in obtaining noncomparable data. Comparison of mortality rates in USA and Russia based on existing ICD coding rules cannot be correctly performed. Therefore, this comparison does not allow to assess contribution of financing and organization of medical service in differences in mortality rates between two countries.

  8. Twelve-hour reanimation of a human heart following donation after circulatory death.

    PubMed

    Rosenfeldt, Franklin; Ou, Ruchong; Woodard, John; Esmore, Donald; Marasco, Silvana

    2014-01-01

    Despite increasing use of donation after cardiac death (DCD) and encouraging results for non-cardiac transplants, DCD cardiac transplantation has not been widely adopted because, (1) the DCD heart sustains warm ischaemic injury during the death process and (2) conventional static cold storage significantly adds to the ischaemic injury. We have developed a simple system for perfusion of the DCD heart with cold crystalloid solution using gravity-feed that can reduce ischaemic injury and potentially render the heart suitable for transplantation. This report describes the first application of this technique to a human DCD heart with good functional metabolic recovery over 12h on an ex vivo rig.

  9. Peristaltic hemodynamics of a new pediatric circulatory assist system for Fontan circulation using shape memory alloy fibers.

    PubMed

    Yamada, A; Shiraishi, Y; Miura, H; Yambe, T; Omran, M H; Shiga, T; Tsuboko, Y; Homma, D; Yamagishi, M

    2013-01-01

    Fontan procedure is one of the common surgical treatments of congenital heart diseases. Patients with Fontan circulation have single ventricle in the systemic circulation with the total cavopulmonary connection. We have been developing a pulmonary circulatory assist device using shape memory alloy fibers for Fontan circulation with total cavopulmonary connection. It consisted of the shape memory alloy fibers, the diameter of which are 100 µm. The fibers could wrap the ePTFE conduit for Fontan TCPC connection from the outside. We designed the sequential motion control system for sophisticated pulmonary hemodynamics by the pulsatile flow generation. In order to achieve pulsatile flow assistance in pulmonary arterial system, we fabricated a mechanical structure by sequential contraction of shape memory alloy fibers. Then, we developed a sequential contraction controller for the assist system, which could reproduce the wall contractile velocity at 6.0 to 20.0 cm/sec. We examined hemodynamic characteristic of its function using a mock circulatory system, which consisted of two overflow tanks representing venous and pulmonary arterial pressures in Fontan circulation. As a result, the pulmonary circulation assist device with sequential contraction could achieve effective promotion of the pulsatility in pulmonary arterial flow.

  10. Atmospheric pressure fluctuations in the far infrasound range and emergency transport events coded as circulatory system diseases

    NASA Astrophysics Data System (ADS)

    Didyk, L. A.; Gorgo, Yu. P.; Dirckx, J. J. J.; Bogdanov, V. B.; Buytaert, J. A. N.; Lysenko, V. A.; Didyk, N. P.; Vershygora, A. V.; Erygina, V. T.

    2008-09-01

    This study examines whether a relation exists between rapid atmospheric pressure fluctuations, attributed to the far infrasound frequency range (APF), and a number of emergency transport events coded as circulatory system diseases (EEC). Over an entire year, the average integral amplitudes of APF in the range of periods from 3 s to 120 s over each hour (HA) were measured. Daily dynamics of HA averaged over the year revealed a wave shape with smooth increase from night to day followed by decrease from day to night. The total daily number of EEC within the city of Kiev, Ukraine, was related to the daily mean of HA (DHA) and to the ratio of HA averaged over the day time to HA averaged over the night time (Rdn), and was checked for confounding effects of classical meteorological variables through non-parametric regression algorithms. The number of EEC were significantly higher on days with high DHA (3.72 11.07 Pa, n = 87) compared to the low DHA (0.7 3.62 Pa, n = 260, p = 0.01), as well at days with low Rdn (0.21 1.64, n = 229) compared to the high Rdn (1.65 7.2, n = 118, p = 0.03). A difference between DHA and Rdn effects on the emergency events related to different categories of circulatory diseases points to a higher sensitivity of rheumatic and cerebro-vascular diseases to DHA, and ischaemic and hypertensive diseases to Rdn. Results suggest that APF could be considered as a meteorotropic factor capable of influencing circulatory system diseases.

  11. Mortality due to diseases of the circulatory system among the elderly population in Brazilian Amazon: temporal and spatial analysis.

    PubMed

    Nunes, Karine Vila Real; Neves, Sandra Mara Alves da Silva; Ignotti, Eliane

    2013-12-01

    Circulatory Diseases (CD) are the major cause of death among the elderly population in Brazilian Amazon. to analyze standardized mortality rates of diseases of the circulatory system (DCS), according to the main causes of death among the elderly, in microregions of the Brazilian Amazon, in the period of 1998 - 2007. ecological study of mortality rates distribution standardized by CD and corrected by deaths from poorly defined causes among the elderly (> 65 years of age) who lived in Brazilian Amazon in the period of 1998 - 2007. The analysis were carried out by the linear regression, trend, and spatial distribution of Kernel. We verified an increasing trend in mortality by CD (β1 = 28.34 p = 0.01), due to the increasing trend in the States of Maranhão and Tocantins. The central region of Mato Grosso, Northern Tocantins, Eastern Pará and Southwestern Maranhão present hot spots with the highest mortality rates. Males present higher rates when compared to females all over the region; rates of mortality due to acute myocardial infarction and hypertensive disease present the same spatial standard of the CD group and the rates of cerebrovascular diseases present a different spatial distribution standard. Increment in mortality rates according to age was observed: the greater the age, the higher is mortality by CD. The Brazilian Amazon presents an increasing trend with high rates of mortality by the circulatory diseases, and the geographic areas with the highest rates are around the Brazilian Amazon, in the states of Tocantins, Maranhão and Mato Grosso.

  12. Systemic activation of the transient receptor potential vanilloid subtype 4 channel causes endothelial failure and circulatory collapse: Part 2.

    PubMed

    Willette, Robert N; Bao, Weike; Nerurkar, Sandhya; Yue, Tian-Li; Doe, Chris P; Stankus, Gerald; Turner, Gregory H; Ju, Haisong; Thomas, Heath; Fishman, Cindy E; Sulpizio, Anthony; Behm, David J; Hoffman, Sandra; Lin, Zuojun; Lozinskaya, Irina; Casillas, Linda N; Lin, Min; Trout, Robert E Lee; Votta, Bartholomew J; Thorneloe, Kevin; Lashinger, Erin S R; Figueroa, David J; Marquis, Robert; Xu, Xiaoping

    2008-08-01

    The transient receptor potential (TRP) vanilloid subtype 4 (V4) is a nonselective cation channel that exhibits polymodal activation and is expressed in the endothelium, where it contributes to intracellular Ca2+ homeostasis and regulation of cell volume. The purpose of the present study was to evaluate the systemic cardiovascular effects of GSK1016790A, a novel TRPV4 activator, and to examine its mechanism of action. In three species (mouse, rat, and dog), the i.v. administration of GSK1016790A induced a dose-dependent reduction in blood pressure, followed by profound circulatory collapse. In contrast, GSK1016790A had no acute cardiovascular effects in the TRPV4-/- null mouse. Hemodynamic analyses in the dog and rat demonstrate a profound reduction in cardiac output. However, GSK1016790A had no effect on rate or contractility in the isolated, buffer-perfused rat heart, and it produced potent endothelial-dependent relaxation of rodent-isolated vascular ring segments that were abolished by nitric-oxide synthase (NOS) inhibition (N-nitro-L-arginine methyl ester; L-NAME), ruthenium red, and endothelial NOS (eNOS) gene deletion. However, the in vivo circulatory collapse was not altered by NOS inhibition (L-NAME) or eNOS gene deletion but was associated with (concentration and time appropriate) profound vascular leakage and tissue hemorrhage in the lung, intestine, and kidney. TRPV4 immunoreactivity was localized in the endothelium and epithelium in the affected organs. GSK1016790A potently induced rapid electrophysiological and morphological changes (retraction/condensation) in cultured endothelial cells. In summary, inappropriate activation of TRPV4 produces acute circulatory collapse associated with endothelial activation/injury and failure of the pulmonary microvascular permeability barrier. It will be important to determine the role of TRPV4 in disorders associated with edema and microvascular congestion.

  13. [The comparison of the two Ottoman books of anatomy (17-19th centuries) with regard to the circulatory system].

    PubMed

    Uluçam, E; Gökçe, N

    2000-01-01

    17th and 19th centuries were particularly important for the development of the Ottoman medicine. Westernization which had already started in the 17th century continued along the 19th and the early 20th centuries. Turkish physicians began to contact with their European colleagues and in this period Latin medical terminology began to appear in the Ottoman medical literature. Sirvanli Semseddin Itaki's work of the 17th century, the Teşrihü'l Ebdan ve Tercüman-i Kibale-i Feylesufan, is the first illustrated Turkish manuscript of anatomy. The illustrations are qualified as developed examples, compared with the medical literature and knowledge of the period. In the 19th century, Sanizade Mehmet Ataullah Efendi (1771-1826) wrote a modern book of anatomy for the Ottoman medical doctors. Miyarü'l Etibba was one of the earliest printed medical books in Turkish. The second volume of Sanizade's Hamse, Miratü'l Ebdan fi Teşrih-i Azai'l Insan is the first printed Ottoman book on anatomy. In Usulü't-Tabia, the third volume of Hamse, the circulatory system is discussed. In this article, we studied the circulatory system described in Semseddin Itaki's Teşrih-ül Ebdan ve Tercüman-i Kibale-i Feylesufan and in Sanizade's Usulü't-Tabia and compared them.

  14. [The comparison of the two Ottoman books of anatomy (17-19th centuries) with regard to the circulatory system].

    PubMed

    Ulucam, E; Gokce, N

    2000-01-01

    17th and 19th centuries were particularly important for the development of te Ottoman medicine. Westernization which had already started in the 17th century continued along the 19th and the early 20th centuries. Turkish physicians began to contact with their European colleagues and in this period Latin medical terminology began to appear in the Ottoman medical literature. Sirvanli Semseddin Itaki's work of the 17th century, the Teşrihü'l Ebdan ve Tercüman-i Kibale-i Feylesufan, is the first illustrated Turkish manuscript of anatomy. The illustrations are qualified as developed examples, compared with the medical literature and knowledge of the period. In the 19th century, Sanizade Mehmet Ataullah Efendi (1771-1826) wrote a modern book of anatomy for the Ottoman medical doctors. Miyarü'l Etibba was one of the earliest printed medical books in Turkish. The second volume of Sanizade's Hamse, Miratü'l Ebdan fi Tesrih-i-Azai'l Insan is the first printed Ottoman book on anatomy. In Usulü't-Tabia, the third volume of Hamse, the circulatory system is discussed. In this article, we studied the circulatory system described in Semseddin Itaki's Teşrih-ül Ebdan ve Tercüman-i-Kibale-i Feylesufan and in Sanizade's Usulü't-Tabia and compared them.

  15. The artificial ventricle: A conceptual design for a novel mechanical circulatory support system.

    PubMed

    Sherif, Hisham M F

    2009-01-01

    We describe a novel design for a new mechanical circulatory support pump which can be utilized for single or biventricular support in a completely internal configuration. The device has a long projected service life, a totally implantable, readily available and off-the-shelf energy source. The proposed device is a pulsatile, positive-displacement blood pump composed of a conically-shaped compliance chamber, constructed of a biocompatible material and attached to two bioprosthetic valves (an inlet valve and an outlet valve), surrounded by radially-arranged contractile elements, made of an electro-active polymer and connected to a common stimulating electrode connected to an implantable permanent pacemaker. The entire assembly is housed in a hermetically sealed biologically inert shell. The energy output from the pacemaker will cause the deformation of the contractile elements and thus compression of the compliance chamber, effecting ejection of the blood through the outlet valve. Based on a design emulating the natural anatomic configuration, the device shall be able to provide clinically significant mechanical assistance and/or replacement of the native heart function and thus a means of supporting the failing ventricle(s) or replacing the failing heart for an extended period of time. The proposed design offers a new pulsatile, positive displacement mechanical circulatory support or replacement for one or both ventricles, is completely implantable, is composed of readily available materials, has minimal energy requirements and an extended service life on internal power supply.

  16. Relationships between Digestive, Circulatory, and Urinary Systems in Portuguese Primary Textbooks

    ERIC Educational Resources Information Center

    Carvalho, Graça S.; Clèment, Pierre

    2007-01-01

    In this study, 63 Portuguese primary schoolbooks (1920-2005) were analyzed. The analysis focused on text information (reference to blood absorption and association of the digestive system to other human systems) and on information from images (presence or absence of image "confusion" (when the sequence of the digestive tract is not…

  17. Mortality from Circulatory System Diseases among French Uranium Miners: A Nested Case-Control Study.

    PubMed

    Drubay, Damien; Caër-Lorho, Sylvaine; Laroche, Pierre; Laurier, Dominique; Rage, Estelle

    2015-05-01

    A significant association has been observed between radon exposure and cerebrovascular disease (CeVD) mortality among French uranium miners, but risk factors for circulatory system diseases (CSD) have not been previously considered. We conducted new analyses in the recently updated (through 2007) French cohort of uranium miners (n = 5,086), which included 442 deaths from CSD, 167 of them from ischemic heart disease (IHD) and 105 from CeVD. A nested case-control study was then set up to collect and investigate the influence of these risk factors on the relationships between mortality from CSD and occupational external gamma ray and internal ionizing radiation exposure (radon and long-lived radionuclides) in this updated cohort. The nested case-control study included miners first employed after 1955, still employed in 1976 and followed up through 2007. Individual information about CSD risk factors was collected from medical files for the 76 deaths from CSD (including 26 from IHD and 16 from CeVD) and 237 miners who had not died of CSD by the end of follow-up. The exposure-risk relationships were assessed with a Cox proportional hazard model weighted by the inverse sampling probability. A significant increase in all CSD and CeVD mortality risks associated with radon exposure was observed in the total cohort [hazard ratios: HRCSD/100 working level months (WLM) = 1.11, 95% confidence interval (1.01; 1.22) and HRCeVD/100 WLM = 1.25 (1.09; 1.43), respectively]. A nonsignificant exposure-risk relationship was observed for every type of cumulative ionizing radiation exposure and every end point [e.g., HRCSD/100WLM = 1.43 (0.71; 2.87)]. The adjustment for each CSD risk factor did not substantially change the exposure-risk relationships. When the model was adjusted for overweight, hypertension, diabetes, hypercholesterolemia and smoking status, the HR/100WLM for CSD, for example, was equal to 1.21 (0.54; 2.75); and when it was adjusted for risk factors selected with the

  18. [Preoperative preparation of pregnant with hypertension according to state of the autonomic nervous system and circulatory system].

    PubMed

    Gur'ianov, V A; Tolmachev, G N; Volodin, A V; Marichik, N V; Nemirovskiĭ, V B; Pivovarova, G M; Shepetovskaia, N L

    2010-01-01

    Pregnancy in patients with hypertension is considered in the spotlight of creation of general adaptation syndrome. According to evidence, when a stable hypertension in pregnant patients with hyper- and eukinetic types of haemodynamics is observed, the response of circulatory system and body fluid compartments has a moderate difference with normal. In pregnant patients with hypertension and a hypokinetic type of haemodynamics and pregnant patients with gestosis developed against the background of eukinetic type of hypertension, a physiological decrease of total peripheral resistance (TPR) is absent, which contributes into interstitial hyperhydration. In pregnant patients with gestosis developed against the background of hypokinetic type of haemodynamics, a pathological rise of TPR occurs, which is followed with a more significant interstitial hyperhydration. A differentiated preoperative preparation of pregnant with hypertension with the calcium antagonists and hydroxyethyl starch solution (130/0,4) favours the conversion of hyper- and hypokinetic types of haemodynamics to eukinetic, forms a physiological type of sympathicotonia and improves the water-salt metabolism.

  19. Long-term allergen exposure induces adipose tissue inflammation and circulatory system injury.

    PubMed

    Jung, Chien-Cheng; Su, Huey-Jen

    2016-05-01

    The purpose of this study was to study whether allergen exposure can induce inflammation and lower the anti-inflammation levels in serum and in adipose tissues, and further develop cardiovascular injury. Our data showed that heart rate was significantly higher in the OVA-challenged mice compared to control mice. Moreover, there were higher expressions of pro-inflammation genes in the OVA-challenged mice in adipose tissues, and the expressions of anti-inflammation genes were lower. The levels of inflammation mediators were associated in serum and adipose tissues. The level of circulatory injury lactate dehydrogenase was significantly associated with the levels of E-selectin, resistin and adiponectin in the serum. The hematoxylin and eosin and immunohistochemistry stains indicated the OVA-challenged mice had higher levels of inflammation. In summary, the current study demonstrated allergen exposure can cause cardiovascular injury, and inflammatory mediators in adipose tissues play an important role in the pathogenesis of cardiovascular injury.

  20. Mean arterial pressure nonlinearity in an elastic circulatory system subjected to different hematocrits.

    PubMed

    Branigan, Tom; Bolster, Diogo; Vázquez, Beatriz Y Salazar; Intaglietta, Marcos; Tartakovsky, Daniel M

    2011-07-01

    The level of hematocrit (Hct) is known to affect mean arterial pressure (MAP) by influencing blood viscosity. In the healthy population, an increase in Hct (and corresponding increase in viscosity) tends to raise MAP. However, data from a clinical study of type 2 diabetic patients indicate that this relationship is not universal. Instead, individuals in the lower levels of Hct range display a decrease in MAP for a given rise in Hct. After reaching a minimum, this trend is reversed, so that further increases in Hct lead to increases in MAP. We hypothesize that this anomalous behavior occurs due to changes in the circulatory autoregulation mechanism. To substantiate this hypothesis, we develop a physically based mathematical model that incorporates autoregulation mechanisms. Our model replicates the anomalous U-shaped relationship between MAP and Hct found in diabetic patients in the same range of Hct variability.

  1. On the contribution of group III and IV muscle afferents to the circulatory response to rhythmic exercise in humans

    PubMed Central

    Amann, Markus; Runnels, Sean; Morgan, David E; Trinity, Joel D; Fjeldstad, Anette S; Wray, D Walter; Reese, Van R; Richardson, Russell S

    2011-01-01

    Abstract We investigated the role of skeletal muscle afferent feedback in circulatory control during rhythmic exercise in humans. Nine healthy males performed single leg knee-extensor exercise (15/30/45 watts, 3 min each) under both control conditions (Ctrl) and with lumbar intrathecal fentanyl impairing μ-opioid receptor-sensitive muscle afferents. Cardiac output and femoral blood flow were determined, and femoral arterial/venous blood samples were collected during the final minute of each workload. To rule out cephalad migration of fentanyl to the brainstem, we documented unchanged resting ventilatory responses to different levels of hypercapnia. There were no haemodynamic differences between conditions at rest. However, during exercise cardiac output was ∼20% lower with fentanyl blockade compared to control (P < 0.05), secondary to a 6% and 13% reduction in heart rate and stroke volume, respectively. Throughout exercise mean arterial pressure (MAP) was reduced by 7% (P < 0.01) which is likely to have contributed to the 15% fall in femoral blood flow. However, MAP was not completely responsible for this peripheral haemodynamic change as vascular conductance was also attenuated (∼9%). Evidence of increasing noradrenaline spillover (P = 0.09) implicated an elevation in sympathetic outflow in this response. The attenuated femoral blood flow during exercise with fentanyl was associated with a 17% reduction in leg O2 delivery (P < 0.01) and a concomitant rise in the arteriovenous O2 difference (4–9%), but leg O2 consumption remained 7–13% lower than control (P < 0.05). Our findings reveal an essential contribution of continuous muscle afferent feedback to ensure the appropriate haemodynamic and ultimately metabolic response to rhythmic exercise in humans. PMID:21646407

  2. Experimental evidence for the existence of the passive antitumor defense system formed by the synergistic action of certain small substances of the circulatory system.

    PubMed

    Kulcsár, Gyula

    2003-12-01

    In AIDS, only a few types of tumors (mainly Kaposi's sarcoma and non-Hodgkin's lymphoma) increase in incidence despite global abnormalities in the immune system. In addition, the reason for the higher incidence of these tumors is not immunosuppression but other agents. This shows that the immune system has no absolute role in the prevention of tumors. Consequently, the fact that tumors do not develop in the majority of the population during their lifetime, indicates the existence of other defense system(s). We demonstrated previously that a mixture of 16 substances (selected experimentally out of 89 compounds of the circulatory system using the synergistic tumor cell-killing effect as criteria) had a cytotoxic effect (inducing apoptosis) in vitro and in vivo on tumor cell lines, but not on normal cells in vitro or animals. In our hypothesis these substances (L-tryptophan, L-tyrosine, L-methionine, L(-)malate, L-ascorbate, L-arginine, L-phenylalanine, L-histidine, 2-deoxy-D-ribose, d-biotin, pyridoxine, adenine, riboflavin, D(+)-mannose, orotate, and hippurate) are the active agents of a passive antitumor defense system (PADS). On the basis of the results, a tablet and a cream were developed, and an infusion is in preclinical phase. In this study we demonstrate that the above-mentioned substances can kill tumor cells when the experimental protocols, concentrations, and cell numbers are chosen to be comparable to the physiological conditions that exist in the living system when these substances fight against arising cancer cells. The results of our experiments demonstrate that the PADS really works in the human body.

  3. Generation of Recombinant Human AChE OP-Scavengers with Extended Circulatory Longevity

    DTIC Science & Technology

    2006-11-01

    correspond to complex-type biantennary forms carrying a fucose moiety, while triantennary glycans (22-30% of the total glycans) were represented to...solid square, GalNAc; elongated diamond, Fucose . Rh, rhesus; Hu, human; Bo, Bovine. ê ê Ä P!!PÄ A 0 5 10 15 20 25 G416S 11.3S 6.1S 100 75 50 kDa 1 2...previously (Kronman et al., 2000; Chitlaru et al., 2001, 2002). These include glycan structures that carry 2 GalNac (MW = 2011.0 Da) or 2 fucose (MW

  4. Do we need a different organ allocation system for kidney transplants using donors after circulatory death?

    PubMed

    Benaragama, Shanka K; Tymkewycz, Teressa; John, Biku J; Davenport, Andrew; Lindsey, Ben; Nicol, David; Olsburgh, Jonathon; Drage, Martin; Mamode, Nizam; Calder, Francis; Taylor, John; Koffman, Geoff; Kessaris, Nicos; Morsy, Mohamed; Cacciola, Roberto; Puliatti, Carmelo; Fernadez-Diaz, Susana; Syed, Asim; Hakim, Nadey; Papalois, Vassilios; Fernando, Bimbi S

    2014-05-22

    There is no national policy for allocation of kidneys from Donation after circulatory death (DCD) donors in the UK. Allocation is geographical and based on individual/regional centre policies. We have evaluated the short term outcomes of paired kidneys from DCD donors subject to this allocation policy. Retrospective analysis of paired renal transplants from DCD's from 2002 to 2010 in London. Cold ischemia time (CIT), recipient risk factors, delayed graft function (DGF), 3 and 12 month creatinine) were compared. Complete data was available on 129 paired kidneys.115 pairs were transplanted in the same centre and 14 pairs transplanted in different centres. There was a significant increase in CIT in kidneys transplanted second when both kidneys were accepted by the same centre (15.5 ± 4.1 vs 20.5 ± 5.8 hrs p<0.0001 and at different centres (15.8 ± 5.3 vs. 25.2 ± 5.5 hrs p=0.0008). DGF rates were increased in the second implant following sequential transplantation (p=0.05). Paired study sequential transplantation of kidneys from DCD donors results in a significant increase in CIT for the second kidney, with an increased risk of DGF. Sequential transplantation from a DCD donor should be avoided either by the availability of resources to undertake simultaneous procedures or the allocation of kidneys to 2 separate centres.

  5. In vivo 3D visualization of peripheral circulatory system using linear optoacoustic array

    NASA Astrophysics Data System (ADS)

    Ermilov, Sergey A.; Brecht, Hans-Peter; Fronheiser, Matthew P.; Nadvoretsky, Vyacheslav; Su, Richard; Conjusteau, Andre; Oraevsky, Alexander A.

    2010-02-01

    In this work we modified light illumination of the laser optoacoustic (OA) imaging system to improve the 3D visualization of human forearm vasculature. The computer modeling demonstrated that the new illumination design that features laser beams converging on the surface of the skin in the imaging plane of the probe provides superior OA images in comparison to the images generated by the illumination with parallel laser beams. We also developed the procedure for vein/artery differentiation based on OA imaging with 690 nm and 1080 nm laser wavelengths. The procedure includes statistical analysis of the intensities of OA images of the neighboring blood vessels. Analysis of the OA images generated by computer simulation of a human forearm illuminated at 690 nm and 1080 nm resulted in successful differentiation of veins and arteries. In vivo scanning of a human forearm provided high contrast 3D OA image of a forearm skin and a superficial blood vessel. The blood vessel image contrast was further enhanced after it was automatically traced using the developed software. The software also allowed evaluation of the effective blood vessel diameter at each step of the scan. We propose that the developed 3D OA imaging system can be used during preoperative mapping of forearm vessels that is essential for hemodialysis treatment.

  6. Circulatory response evoked by a 3 s bout of dynamic leg exercise in humans.

    PubMed Central

    Wieling, W; Harms, M P; ten Harkel, A D; van Lieshout, J J; Sprangers, R L

    1996-01-01

    1. The mechanisms underlying the pronounced transient fall in arterial blood pressure evoked by a 3 s bout of bicycle exercise were investigated in twenty healthy young adults and four patients with hypoadrenergic orthostatic hypotension. 2. In healthy subjects a 3 s bout of upright cycling induced a 28 +/- 3 mmHg fall in mean arterial pressure at 12 s. The fall in mean arterial pressure was preceded by a 12 +/- 2 mmHg rise in right atrial pressure at 3 s and accompanied by a 54 +/- 7% increase in left ventricle stroke volume at 6 s. Systemic vascular resistance dropped 48 +/- 2% at 7 s after the start of the manoeuvre to remain at that level for approximately 5 s. The total response lasted about 20 s. During sustained upright cycling the initial fall in mean arterial pressure was also present, but less pronounced (17 +/- 2 vs. 26 +/- 3 mmHg). A 3 s bout of supine cycling in four patients with hypoadrenergic orthostatic hypotension also elicited a pronounced fall in mean arterial pressure (22 +/- 4 mmHg) and in systemic vascular resistance (38 +/- 4%). 3. A bout of exercise with a large muscle mass induces two main effects. First, it mechanically increases filling of the heart due to activation of the muscle pump, resulting in an increase in cardiac output. Second, it induces a drop in systemic vascular resistance. The increase in cardiac output is not sufficient to compensate fully for the pronounced fall in systemic vascular resistance and the result is a transient fall in arterial pressure at the onset of whole-body exercise. The rise in right atrial pressure evoked by 3 s cycling is abrupt and large, but the almost immediate onset and rapid fall of the systemic vascular resistance is too fast for sympathetically mediated reflex effects due to stimulation of the cardiopulmonary afferents. An important factor involved in the drop in systemic vascular resistance appears to be local, non-autonomically mediated vasodilatation in exercising muscles, since it also

  7. Circulatory response evoked by a 3 s bout of dynamic leg exercise in humans.

    PubMed

    Wieling, W; Harms, M P; ten Harkel, A D; van Lieshout, J J; Sprangers, R L

    1996-07-15

    1. The mechanisms underlying the pronounced transient fall in arterial blood pressure evoked by a 3 s bout of bicycle exercise were investigated in twenty healthy young adults and four patients with hypoadrenergic orthostatic hypotension. 2. In healthy subjects a 3 s bout of upright cycling induced a 28 +/- 3 mmHg fall in mean arterial pressure at 12 s. The fall in mean arterial pressure was preceded by a 12 +/- 2 mmHg rise in right atrial pressure at 3 s and accompanied by a 54 +/- 7% increase in left ventricle stroke volume at 6 s. Systemic vascular resistance dropped 48 +/- 2% at 7 s after the start of the manoeuvre to remain at that level for approximately 5 s. The total response lasted about 20 s. During sustained upright cycling the initial fall in mean arterial pressure was also present, but less pronounced (17 +/- 2 vs. 26 +/- 3 mmHg). A 3 s bout of supine cycling in four patients with hypoadrenergic orthostatic hypotension also elicited a pronounced fall in mean arterial pressure (22 +/- 4 mmHg) and in systemic vascular resistance (38 +/- 4%). 3. A bout of exercise with a large muscle mass induces two main effects. First, it mechanically increases filling of the heart due to activation of the muscle pump, resulting in an increase in cardiac output. Second, it induces a drop in systemic vascular resistance. The increase in cardiac output is not sufficient to compensate fully for the pronounced fall in systemic vascular resistance and the result is a transient fall in arterial pressure at the onset of whole-body exercise. The rise in right atrial pressure evoked by 3 s cycling is abrupt and large, but the almost immediate onset and rapid fall of the systemic vascular resistance is too fast for sympathetically mediated reflex effects due to stimulation of the cardiopulmonary afferents. An important factor involved in the drop in systemic vascular resistance appears to be local, non-autonomically mediated vasodilatation in exercising muscles, since it also

  8. Additional N-glycosylation in the N-terminal region of recombinant human alpha-1 antitrypsin enhances the circulatory half-life in Sprague-Dawley rats.

    PubMed

    Chung, Hye-Shin; Kim, Ji-Sun; Lee, Sang Mee; Park, Soon Jae

    2016-04-01

    Glycosylation affects the circulatory half-lives of therapeutic proteins. However, the effects of an additional N-glycosylation in the unstructured region or the loop region of alpha-1 antitrypsin (A1AT) on the circulatory half-life of the protein are largely unknown. In this study, we investigated the role of an additional N-glycosylation site (Q4N/D6T, Q9N, D12N/S14T, A70N, G148T, R178N, or V212N) to the three naturally occurring N-glycosylation sites in human A1AT. A single-dose (445 μg/kg) pharmacokinetic study using male Sprague-Dawley rats showed that, among the seven recombinant A1AT (rA1AT) mutants, Q9N and D12N/S14T showed the highest serum concentration and area under the curve values, as well as similar circulatory half-lives that were 2.2-fold higher than plasma-derived A1AT and 1.7-fold higher than wild-type rA1AT. We further characterized the Q9N mutant regarding the N-glycan profile, sialic acid content, protease inhibitory activity, and protein stability. The results indicate that an additional N-glycosylation in the flexible N-terminal region increases the circulatory half-life of rA1AT without altering its protease inhibitory activity. Our study provides novel insight into the use of rA1AT for the treatment of emphysema with an increased injection interval relative to the clinically used plasma-derived A1AT.

  9. Do we need a different organ allocation system for kidney transplants using donors after circulatory death?

    PubMed Central

    2014-01-01

    Background There is no national policy for allocation of kidneys from Donation after circulatory death (DCD) donors in the UK. Allocation is geographical and based on individual/regional centre policies. We have evaluated the short term outcomes of paired kidneys from DCD donors subject to this allocation policy. Methods Retrospective analysis of paired renal transplants from DCD’s from 2002 to 2010 in London. Cold ischemia time (CIT), recipient risk factors, delayed graft function (DGF), 3 and 12 month creatinine) were compared. Results Complete data was available on 129 paired kidneys.115 pairs were transplanted in the same centre and 14 pairs transplanted in different centres. There was a significant increase in CIT in kidneys transplanted second when both kidneys were accepted by the same centre (15.5 ± 4.1 vs 20.5 ± 5.8 hrs p < 0.0001 and at different centres (15.8 ± 5.3 vs. 25.2 ± 5.5 hrs p = 0.0008). DGF rates were increased in the second implant following sequential transplantation (p = 0.05). Conclusions Paired study sequential transplantation of kidneys from DCD donors results in a significant increase in CIT for the second kidney, with an increased risk of DGF. Sequential transplantation from a DCD donor should be avoided either by the availability of resources to undertake simultaneous procedures or the allocation of kidneys to 2 separate centres. PMID:24885114

  10. Effect of micro mist sauna bathing on thermoregulatory and circulatory functions and thermal sensation in humans

    NASA Astrophysics Data System (ADS)

    Iwase, Satoshi; Kawahara, Yuko; Nishimura, Naoki; Sugenoya, Junichi

    2016-05-01

    moderate and effective thermal effect during micro mist sauna bathing than the conventional mist sauna bathing. In addition, micro mist sauna is as effective for heating the human subjects as bathtub bathing as well as more moderate thermal and sweating sensations.

  11. Effect of micro mist sauna bathing on thermoregulatory and circulatory functions and thermal sensation in humans.

    PubMed

    Iwase, Satoshi; Kawahara, Yuko; Nishimura, Naoki; Sugenoya, Junichi

    2016-05-01

    more moderate and effective thermal effect during micro mist sauna bathing than the conventional mist sauna bathing. In addition, micro mist sauna is as effective for heating the human subjects as bathtub bathing as well as more moderate thermal and sweating sensations.

  12. Model-Based Comparison of the Normal and Fontan Circulatory Systems-Part II: Major Differences in Performance Characteristics.

    PubMed

    Chin, Alvin J; Watrous, Raymond L

    2015-07-01

    In the absence of an accessible chronic animal model of the Fontan circulation, computational modeling can provide insights into this unique circulatory arrangement, especially how differently it behaves from the normal mammalian circulation. Many groups have focused on refining a single element of the entire Fontan circulation-the total cavopulmonary connection (TCPC). Yet, only modest improvements in transplant-free survival have resulted. From an engineering perspective, optimizing the performance of a complex, multiparameter system requires an understanding of how the performance is affected by the full set of system parameters. We evaluated the hemodynamic impact of nine physiological perturbations in the two-year-old (yo) patient with hypoplastic left heart syndrome having a Fontan rearrangement (using our previously described lumped-parameter multicompartment model of both pulmonary and systemic circulations). In cases where comparison is appropriate, we evaluated the hemodynamic impact of analogous pathophysiologies in the normal two-year-olds. We operated the model in open-loop mode in order to expose the magnitude of the impact of uncompensated physiological perturbations. Without the benefit of compensatory mechanisms, a valvar regurgitant fraction of 50% is sufficient to drop the cardiac index (CI) to 2.0 L/min/m(2) or less. Aortopulmonary collateral flow of 0.6 L/min (1.1 L/min/m(2)) or 0.5 L/min (0.9 L/min/m(2)), sufficient to raise the ratio of pulmonary flow to systemic flow (Qp/Qs) to no higher than 1.2 or 1.5 (fenestration present or absent, respectively), is the maximum which could be tolerated (CI = 2.0 L/min/m(2)) without the help of compensatory mechanisms. Ventricular end-diastolic elastance (stiffness) changes have dramatic effects on CI in a Fontan circulatory arrangement. Several components of the Fontan circulation other than the TCPC actually have equal, or greater, impact on CI under certain conditions. © The Author(s) 2015.

  13. [Effect of intra-abdominal pressure on respiratory system, circulatory system and renal function in rats and study on the method of determination of intra-abdominal pressure].

    PubMed

    Ge, Liang; He, Qian; Zhang, Shao-Bo; Cheng, Jun-Tao; Zhang, Cheng-Hua

    2009-04-01

    OBJECTIVE To study the effects of intra-abdominal pressure (IAP) on respiratory system, circulatory system and renal function in rats. To investigate the difference between the direct measure and indirect measure methods (via inferior vena cava and bladder) for IAP. Sixty Sprague-Drawly (SD) rats were randomly divided into 5 groups with different IAP (IAP value of 1-5 groups was 5, 10, 15, 20, 25 mm Hg,respectively) and healthy control group, 10 rats in each group. The parameters of respiratory system, circulatory system, renal function, and IAP value were recorded. The correlation between direct and indirect measurement methods was also analyzed. There were no significant differences in above parameters between IAPI and healthy control groups. Compared with those in healthy control group, PaO2 significantly decreased (P < 0.05), SCr and BUN increased significantly in IAP2 group (P < 0.05). Other indexes in IAP3, IAP4 groups increased (P < 0.05 or P < 0.01) except for respiratory frequency(RF) and MAP (P > 0.05). PaO2 and MAP decreased (P < 0.01), and other indexes increased (P < 0.05 or P < 0.01) in IAP5 group. The values obtained from the indirect measure method were positively correlated with that from the direct measure method (r = 0.937, 0.955, P < 0.01, respectively). IAP can affect respiratory system, circulatory system and renal function in different degrees in rats. The indirect measure method can replace the direct measure method for IAP measure with little injuries.

  14. Overview of the 2016 U.S. Food and Drug Administration Circulatory System Devices Advisory Panel Meeting on the Absorb Bioresorbable Vascular Scaffold System.

    PubMed

    Steinvil, Arie; Rogers, Toby; Torguson, Rebecca; Waksman, Ron

    2016-09-12

    This study aims to describe the discussions and recommendations made during the U.S. Food and Drug Administration (FDA) Circulatory System Device Panel pre-market approval application for the Absorb Bioresorbable Vascular Scaffold (BVS) System. The Absorb BVS System is a first-of-its-kind fully bioresorbable percutaneous coronary intervention technology. The absorb BVS was studied in the ABSORB III (A Clinical Evaluation of Absorb BVS, the Everolimus Eluting Bioresorbable Vascular Scaffold in the Treatment of Subjects with de Novo Native Coronary Artery Lesions) trial, the pivotal U.S. investigational device exemption trial. Observational report of the FDA Circulatory System Device Panel pre-market approval application meeting held on March 15, 2016. The U.S. FDA Circulatory System Device Panel members reviewed the ABSROB III trial outcomes and additional post hoc analyses presented by the sponsor and the FDA. The ABSORB III trial met the primary endpoint of noninferiority of Absorb BVS compared with the control, XIENCE drug-eluting stent, for target lesion failure at 1 year. Although a higher numerical trend for adverse outcomes was reported for the Absorb BVS, there were no statistical differences between Absorb BVS and XIENCE for any safety or effectiveness components for target lesion failure or for the secondary pre-specified outcomes. Panel members raised concerns with regard to the ABSORB III results and post hoc analyses focusing mainly on the noninferiority design of the trial, the apparent safety issues of the Absorb BVS in small vessels, the mismatch of visually versus intravascular imaging assessed vessel size found in ABSORB III and its implications on the adequate device labeling, the safety of Absorb BVS in specific patient and lesion subsets, and the post-approval commitments of the sponsor. Following panel discussions and the evidence presented, the panel voted for approval of the device. Copyright © 2016 American College of Cardiology Foundation

  15. A fast building and effective hydraulic pediatric mock circulatory system for the evaluation of a left ventricular assist device.

    PubMed

    Huang, Feng; Ruan, Xiaodong; Zou, Jun; Qian, Wenwei; Fu, Xin

    2013-01-01

    A mock circulatory system (MCS) has been proven a useful tool in the development of a ventricular assist device. Nowadays a MCS aimed at the evaluation of pediatric blood pumps, which require many different considerations compared with that of adults, has become an urgent need. This article presents the details on how the dynamic process of the left ventricle, which is described in terms of the pressure-volume loop (P-V loop), and the properties of the circulation such as compliance and resistance are simulated by hydraulic elements. A simple control method is introduced to reproduce the physiological afterload and preload sensitivities of the mock ventricle for the first time. Hemodynamic performance of the system is obtained by medical sensors to validate the similarity of the device to the native cardiovascular system. The actual sensitivities of the mock ventricle are obtained intuitively from the changes of the P-V loops. The aortic input impedance of the MCS is also obtained and compared with the data from previous medical reports. At last a pediatric left ventricular assist device (LVAD) prototype is introduced for testing to further verify the effectiveness of the MCS. The experimental results indicate that this pediatric MCS is capable of reproducing basic hemodynamic characteristics of a child in both normal and pathological conditions and it is sufficient for testing a pediatric LVAD. Besides, most components constituting the main hydraulic part of this MCS are inexpensive off-the-shelf products, making the MCS easy and fast to build.

  16. Influence of apnoeic oxygenation in respiratory and circulatory system under general anaesthesia

    PubMed Central

    Kolettas, Alexander; Grosomanidis, Vasilis; Kolettas, Vasilis; Tsakiridis, Kosmas; Katsikogiannis, Nikolaos; Tsiouda, Theodora; Kiougioumtzi, Ioanna; Machairiotis, Nikolaos; Drylis, Georgios; Kesisis, Georgios; Beleveslis, Thomas; Zarogoulidis, Konstantinos

    2014-01-01

    Apnoeic oxygenation is an alternative technique of oxygenation which is recommended in the consecutive oxygen administration with varying flows (2-10 lt/min) through a catheter which is positioned over the keel of the trachea. Apnoeic oxygenation maintains for a significant period of time the oxygenation of blood in breathless conditions. This technique was first applied in 1947 by Draper, Whitehead, and Spencer and it was studied sporadically by other inventors too. However, the international literature shows few studies that have examined closely apnoeic oxygenation and its effects on Hemodynamic image and the respiratory system of the human body. Recently they have begun to arise some studies which deal with the application of this technique in several conditions such as difficult tracheal intubation, ventilation of guinea pigs in campaign conditions where the oxygen supply is limited and calculable, the application of this technique in combination with the use of extracorporeal removal of carbon dioxide (CO2). All the above indicate, the clinical use of this technique. PMID:24672687

  17. Influence of apnoeic oxygenation in respiratory and circulatory system under general anaesthesia.

    PubMed

    Kolettas, Alexander; Grosomanidis, Vasilis; Kolettas, Vasilis; Zarogoulidis, Paul; Tsakiridis, Kosmas; Katsikogiannis, Nikolaos; Tsiouda, Theodora; Kiougioumtzi, Ioanna; Machairiotis, Nikolaos; Drylis, Georgios; Kesisis, Georgios; Beleveslis, Thomas; Zarogoulidis, Konstantinos

    2014-03-01

    Apnoeic oxygenation is an alternative technique of oxygenation which is recommended in the consecutive oxygen administration with varying flows (2-10 lt/min) through a catheter which is positioned over the keel of the trachea. Apnoeic oxygenation maintains for a significant period of time the oxygenation of blood in breathless conditions. This technique was first applied in 1947 by Draper, Whitehead, and Spencer and it was studied sporadically by other inventors too. However, the international literature shows few studies that have examined closely apnoeic oxygenation and its effects on Hemodynamic image and the respiratory system of the human body. Recently they have begun to arise some studies which deal with the application of this technique in several conditions such as difficult tracheal intubation, ventilation of guinea pigs in campaign conditions where the oxygen supply is limited and calculable, the application of this technique in combination with the use of extracorporeal removal of carbon dioxide (CO2). All the above indicate, the clinical use of this technique.

  18. Enhancement of Arterial Pressure Pulsatility by Controlling Continuous-Flow Left Ventricular Assist Device Flow Rate in Mock Circulatory System.

    PubMed

    Bozkurt, Selim; van de Vosse, Frans N; Rutten, Marcel C M

    Continuous-flow left ventricular assist devices (CF-LVADs) generally operate at a constant speed, which reduces pulsatility in the arteries and may lead to complications such as functional changes in the vascular system, gastrointestinal bleeding, or both. The purpose of this study is to increase the arterial pulse pressure and pulsatility by controlling the CF-LVAD flow rate. A MicroMed DeBakey pump was used as the CF-LVAD. A model simulating the flow rate through the aortic valve was used as a reference model to drive the pump. A mock circulation containing two synchronized servomotor-operated piston pumps acting as left and right ventricles was used as a circulatory system. Proportional-integral control was used as the control method. First, the CF-LVAD was operated at a constant speed. With pulsatile-speed CF-LVAD assistance, the pump was driven such that the same mean pump output was generated. Continuous and pulsatile-speed CF-LVAD assistance provided the same mean arterial pressure and flow rate, while the index of pulsatility increased significantly for both arterial pressure and pump flow rate signals under pulsatile speed pump support. This study shows the possibility of improving the pulsatility of CF-LVAD support by regulating pump speed over a cardiac cycle without reducing the overall level of support.

  19. The circulatory system in Mysidacea--implications for the phylogenetic position of Lophogastrida and Mysida (Malacostraca, Crustacea).

    PubMed

    Wirkner, Christian S; Richter, Stefan

    2007-04-01

    The morphology of the circulatory organs in Mysida and Lophogastrida (traditionally combined as Mysidacea) is revisited investigating species so far unstudied. In addition to classical morphological methods, a newly developed combination of corrosion casting with micro computer tomography (MicroCT) and computer aided 3D reconstructions is used. Lophogastrida and Mysida show a highly developed arterial system. The tubular heart extends through the greater part of the thorax and is connected with the ventral vessel via an unpaired descending artery. It is suggested that a distinct ostia pattern supports the monophyly of Mysidacea. The cardiac artery system is more complex in Lophogastrida than in Mysida, consisting of up to 10 pairs of arteries that supply the viscera. In both taxa, an anterior and posterior aorta leads off the heart. In the anterior part of the cephalothorax the anterior aorta forms dilations into which muscles are internalized; these structures are called myoarterial formations. One of these myoarterial formations can also be found in all the other peracarid taxa but not in other Malacostraca. Copyright (c) 2007 Wiley-Liss, Inc.

  20. Changes in the central and peripheral circulatory system in response to the cold: own studies using impedance plethysmography and Doppler ultrasound.

    PubMed

    Łastowiecka-Moras, Elżbieta; Kozyra-Pydyś, Eliza

    2016-12-01

    The aim of the study was to determine the cardiovascular response to continuous (4 °C for 60 min) and intermittent (10 min at 4 °C and 10 min at room temperature alternately) exposure to the cold in 30 healthy young men. The subjects were equipped with a set of identical clothing (insulation 2.1 clo) and during the stay in the chamber and outside performed the same activities, i.e., walking on a treadmill at a speed of 0.5 km/h. The tests included assessing the central circulatory system using the Holter system and assessing the peripheral circulatory system using impedance plethysmography and Doppler ultrasound. The analysis of the parameters that describe the central and peripheral circulation poses a difficulty in determining which variant of exposure constitutes a greater load on the circulatory system. It should be noted that even the conditions used in the study may cause adverse effects in the cardiovascular system.

  1. Effect of valsalva in the pulmonary prosthetic conduit valve on hemodynamic function in a mock circulatory system.

    PubMed

    Tsuboko, Yusuke; Shiraishi, Yasuyuki; Yamada, Akihiro; Yambe, Tomoyuki; Matsuo, Satoshi; Saiki, Yoshikatsu; Yamagishi, Masaaki

    2015-01-01

    Pulmonary conduit valves are used as one of the surgical treatment methods of congenital heart diseases. We have been designing a sophisticated pulmonary conduit valve for the right ventricular outflow tract reconstruction in pediatric patients. In this study, two types of polyester grafts with or without bulging structures for the conduit valves were used and evaluated from the hemodynamic point of view focusing on the application of these conduit valves in the grown-up congenital heart failure patients. We examined valvular function in the originally developed pulmonary mock circulatory system, which consisted of a pneumatic driven right ventricular model, a pulmonary valve chamber, and an elastic pulmonary compliance model with peripheral vascular resistance units. Prior to the measurement, a bileaflet valve was sutured in each conduit. Each conduit valve was installed in the mock right ventricular outflow portion, and its leaflet motion was obtained by using a high-speed camera synchronously with pressure and flow waveforms. As a result, we could obtain hemodynamic changes in two different types of conduits for pulmonary valves, and it was indicated that the presence of the Valsalva shape might be effective for promoting valvular response in the low cardiac output condition.

  2. Stagnation point flow and heat transfer on a thin porous sheet: Applications to flow dynamics of the circulatory system

    NASA Astrophysics Data System (ADS)

    Misra, J. C.; Sinha, A.; Mallick, B.

    2017-03-01

    The paper is concerned with the modeling and analysis of stagnation point flow and heat transfer on a thin porous sheet under the action of an induced magnetic field. The fluid is considered to be incompressible viscous and electrically conducting. The study is motivated towards exploring some interesting phenomena in the micro-circulatory system. Heat transfer is considered to be governed by the heat equation. In order to take care of the induced magnetism that affects the flow process, the flow equations are coupled with magnetic field variables. The analysis has been performed under the purview of the boundary layer theory, together with the use of similarity transformation. The transformed equations are solved by developing an appropriate numerical method. Numerical results have been computed for a typical situation of the fluid in motion. The results are displayed graphically/in tabular form, which depict the distribution of velocity and temperature under the action of the induced magnetic field and permeability of the porous sheet. The study shows that the flow of the fluid reduces, as the strength of the induced magnetic field increases. However, the reduction in velocity is accompanied by an enhancement of the temperature field.

  3. A new method of providing pulsatile flow in a centrifugal pump: assessment of pulsatility using a mock circulatory system.

    PubMed

    Herreros, Jesús; Berjano, Enrique J; Sales-Nebot, Laura; Más, Pedro; Calvo, Irene; Mastrobuoni, Stefano; Mercé, Salvador

    2008-06-01

    Previous studies have demonstrated the potential advantages of pulsatile flow as compared with continuous flow. However, to date, physiologic pumps have been technically complex and their application has therefore remained in the experimental field. We have developed a new type of centrifugal pump, which can provide pulsatile as well as continuous flow. The inner wall of a centrifugal pump is pulsed by means of a flexible membrane, which can be accurately controlled by means of either a hydraulic or pneumatic driver. The aim of this study was to assess the hydraulic behavior of the new pump in terms of surplus hemodynamic energy (SHE). We conducted experiments using a mock circulatory system including a membrane oxygenator. No differences were found in the pressure-flow characteristics between the new pump and a conventional centrifugal pump, suggesting that the inclusion of the flexible membrane does not alter hydraulic performance. The value of SHE rose when systolic volume was increased. However, SHE dropped when the percentage of ejection time was reduced and also when the continuous flow (programmed by the centrifugal console) increased. Mean flow matched well with the continuous flow set by the centrifugal console, that is, the pulsatile component of the flow was exclusively controlled by the pulsatile console, and was therefore independent of the continuous flow programmed by the centrifugal console. The pulsatility of the new pump was approximately 25% of that created with a truly pulsatile pump.

  4. A biplane roentgen videometry system for dynamic /60 per second/ studies of the shape and size of circulatory structures, particularly the left ventricle.

    NASA Technical Reports Server (NTRS)

    Ritman, E. L.; Sturm, E.; Wood, E. H.; Heintzen, P. H.

    1971-01-01

    A roentgen-television digital-computer technique and a display system developed for dynamic circulatory structure studies are described. Details are given for a videoroentgenographic setup which is used for obtaining biplane roentgen silhouettes of a left ventricle. A 60 per sec measurement of the shape and volume of angiographically outlined cardiac chambers can be made by this technique along with simultaneous ECG, pressure, and flow measurements accessible for real-time digital computer processing and analysis.

  5. Effects of alfapump system on kidney and circulatory function in patients with cirrhosis and refractory ascites.

    PubMed

    Solà, Elsa; Sanchez-Cabús, Santiago; Rodriguez, Ezequiel; Elia, Chiara; Cela, Raquel; Moreira, Rebeca; Pose, Elisa; Sánchez-Delgado, Jordi; Cañete, Nuria; Morales-Ruiz, Manuel; Campos, Francisco; Balust, Jaume; Guevara, Mónica; García-Valdecasas, Juan Carlos; Ginès, Pere

    2017-03-20

    The alfapump system has been proposed as a new treatment for the management of refractory ascites. The system removes ascites from the peritoneal cavity to urinary bladder, producing a continuous low-volume paracentesis.

  6. [Effects of kavergal on indices of lipid peroxidation and the condition of the antioxidant system in patients with rheumatic heart disease presenting with circulatory insufficiency].

    PubMed

    Abdullaev, S F; Inoiatova, F Kh; Inoiatov, F Sh

    2002-01-01

    132 patients with rheumatic heart disease presenting with circulatory insufficiency displayed increased LPO both in the blood plasma and red cells, decline in the antioxidant enzymes activity varying with the circulatory insufficiency functional class degree of severity. Basic therapy with making use of antiinflammatory drugs, cardiac glycosides, diuretics together with drugs endowed with an antiarrhythmic activity and nitroglycerin (where indicated) was found to have practically no effect on LPO level or activity of the antioxidant system. The use of the drug kavergal, 1 g three times daily (total daily dosage being 3 g) in the complex therapy, has been shown to significantly decrease hyperlipoperoxidation both in the blood plasma and red cells increasing the activity of enzymes of the antioxidant defence.

  7. Active musculoskeletal structures equipped with a circulatory system and a network of ionic polymeric gel muscles

    SciTech Connect

    Shahinpoor, M.; Mojarrad, M.

    1994-12-31

    Presented are descriptions of design and fabrication of an active musculoskeletal structure composed of an artificial human skeleton of 5.3 feet in height. This skeletal structure is further equipped with an artificial heart in the form of a multi-channel computer-controlled fluid pump. The fluid pump may be programmed to selectively pump either an acid, a base or de-ionized water to a network of veins that feed a network of pairs of antagonist contractile synthetic muscles. These muscles are manufactured in the laboratory from polyacrylonitrile (PAN) fiber bundles that are specially designed and packaged inside flexible, hyperelastic latex membranes. Each pair of muscles act as a pair of antagonist actuator similar to the biceps and triceps muscles of the human arm. The initial fabrication indicates that it is possible to dynamically control such active musculoskeletal structures. A model is also presented for the dynamic control of such antagonist muscles. The model is intended to be used to study the human musculoskeletal dynamics.

  8. Investigation of a Micro-test for Circulatory Autonomic Nervous System Responses.

    PubMed

    Moser, Maximilian; Frühwirth, Matthias; Messerschmidt, Dietmar; Goswami, Nandu; Dorfer, Leopold; Bahr, Frank; Opitz, Gerhard

    2017-01-01

    Aims and Objectives: The autonomic nervous system plays an important role in homeostasis and organismic recreation, control of immune function, inflammation, and bone growth. It also regulates blood pressure and orthostasis via vagal and sympathetic pathways. Besides recording of heart rate variability (HRV), which characterizes medium (1-5 min) and long term (circadian) autonomic tone or modulation, no gentle tests of short-term autonomic reactivity and control are available. In 1976 Nogier described a short time cardiovascular response ("Réflexe Auriculo Cardiaque", RAC) which could be used to investigate short term autonomic reactions without changing system characteristics and thus being repeatable in short intervals. In this paper, we investigated the possible application of the Nogier reaction as a micro-test for the identification of a disturbed sensitivity or reactivity of the autonomic nervous system. Methods: We statistically analyzed cardiovascular signals derived during the application of small repeated stimuli utilizing methods of signal averaging to characterize the physiological background. Specifically, the Nogier reaction was investigated using simultaneous recordings of ECG, pulse waves, and respiration. Results: Significant fast (delay 1-5 s) and slower (delay 6-12 s) cardio-autonomic responses to different stimuli which characterize short term were observed. From time characteristics and type of signals where they occur we deduce that fast changes observed in heart rate are vagal reactions to the small stimuli whereas slower changes observed in pulse waves stem from sympathetic nervous system responses. Conclusions: The investigated autonomic micro-test opens the possibility to differentially investigate both limbs of the autonomic nervous system with minimal stimuli. It can be performed within seconds and does not change the set point of the system in opposition to less subtle tests such as Valsalva maneuver. Therefore, it is well-suited for

  9. On the destabilizing effect of damping on discrete and continuous circulatory systems

    NASA Astrophysics Data System (ADS)

    Luongo, Angelo; D`Annibale, Francesco

    2014-12-01

    The 'Ziegler paradox', concerning the destabilizing effect of damping on elastic systems loaded by nonconservative positional forces, is addressed. The paper aims to look at the phenomenon in a new perspective, according to which no surprising discontinuities in the critical load exist between undamped and damped systems. To show that the actual critical load is found as an (infinitesimal) perturbation of one of the infinitely many sub-critically loaded undamped systems. A series expansion of the damped eigenvalues around the distinct purely imaginary undamped eigenvalues is performed, with the load kept as a fixed, although unknown, parameter. The first sensitivity of the eigenvalues, which is found to be real, is zeroed, so that an implicit expression for the critical load multiplier is found, which only depends on the 'shape' of damping, being independent of its magnitude. An interpretation is given of the destabilization paradox, by referring to the concept of 'modal damping', according to which the sign of the projection of the damping force on the eigenvector of the dual basis, and not on the eigenvector itself, is the true responsible for stability. The whole procedure is explained in detail for discrete systems, and successively extended to continuous systems. Two sample structures are studied for illustrative purposes: the classical reverse double-pendulum under a follower force and a linear visco-elastic beam under a follower force and a dead load.

  10. Programmatic Summary: Self-Regulating, Self-Pressurizing Tubules for Integrated Circulatory Systems

    DTIC Science & Technology

    2009-02-01

    14. ABSTRACT In this Director’s Research Initiative (DRI) effort, we have developed surface treatments with cleavable Diels - Alder bonds that...surface properties. .........................................1 Figure 2. Reversible Diels - Alder adduct (purple), whose formation is temperature...system is the development of surfaces with actively controllable surface energy. One approach is using Diels - Alder chemistry. In a traditional Diels

  11. Mock circulatory system of the Fontan circulation to study respiration effects on venous flow behavior.

    PubMed

    Vukicevic, Marija; Chiulli, John A; Conover, Timothy; Pennati, Giancarlo; Hsia, Tain Yen; Figliola, Richard S

    2013-01-01

    We describe an in vitro model of the Fontan circulation with respiration to study subdiaphragmatic venous flow behavior. The venous and arterial connections of a total cavopulmonary connection (TCPC) test section were coupled with a physical lumped parameter (LP) model of the circulation. Intrathoracic and subdiaphragmatic pressure changes associated with normal breathing were applied. This system was tuned for two patients (5 years, 0.67 m2; 10 years, 1.2 m2) to physiological values. System function was verified by comparison to the analytical model on which it was based and by consistency with published clinical measurements. Overall, subdiaphragmatic venous flow was influenced by respiration. Flow within the arteries and veins increased during inspiration but decreased during expiration, with retrograde flow in the inferior venous territories. System pressures and flows showed close agreement with the analytical LP model (p < 0.05). The ratio of the flow rates occurring during inspiration to expiration were within the clinical range of values reported elsewhere. The approach used to set up and control the model was effective and provided reasonable comparisons with clinical data.

  12. Reproduction of Consistent Pulse-Waveform Changes Using a Computational Model of the Cerebral Circulatory System

    PubMed Central

    Connolly, Mark; He, Xing; Gonzalez, Nestor; Vespa, Paul; DiStefano, Joe; Hu, Xiao

    2014-01-01

    Due to the inaccessibility of the cranial vault, it is difficult to study cerebral blood flow dynamics directly. A mathematical model can be useful to study these dynamics. The model presented here is a novel combination of a one-dimensional fluid flow model representing the major vessels of the circle of Willis (CoW), with six individually parameterized auto-regulatory models of the distal vascular beds. This model has the unique ability to simulate high temporal resolution flow and velocity waveforms, amenable to pulse-waveform analysis, as well as sophisticated phenomena such as auto-regulation. Previous work with human patients has shown that vasodilation induced by CO2 inhalation causes 12 consistent pulse-waveform changes as measured by the Morphological Clustering and Analysis of Intracranial Pressure algorithm. To validate this model, we simulated vasodilation and successfully reproduced 9 out of the 12 pulse-waveform changes. A subsequent sensitivity analysis found that these 12 pulse-waveform changes were most affected by the parameters associated with the shape of the smooth muscle tension response and vessel elasticity, providing insight into the physiological mechanisms responsible for observed changes in the pulse-waveform shape. PMID:24389244

  13. Reproduction of consistent pulse-waveform changes using a computational model of the cerebral circulatory system.

    PubMed

    Connolly, Mark; He, Xing; Gonzalez, Nestor; Vespa, Paul; DiStefano, Joe; Hu, Xiao

    2014-03-01

    Due to the inaccessibility of the cranial vault, it is difficult to study cerebral blood flow dynamics directly. A mathematical model can be useful to study these dynamics. The model presented here is a novel combination of a one-dimensional fluid flow model representing the major vessels of the circle of Willis (CoW), with six individually parameterized auto-regulatory models of the distal vascular beds. This model has the unique ability to simulate high temporal resolution flow and velocity waveforms, amenable to pulse-waveform analysis, as well as sophisticated phenomena such as auto-regulation. Previous work with human patients has shown that vasodilation induced by CO2 inhalation causes 12 consistent pulse-waveform changes as measured by the morphological clustering and analysis of intracranial pressure algorithm. To validate this model, we simulated vasodilation and successfully reproduced 9 out of the 12 pulse-waveform changes. A subsequent sensitivity analysis found that these 12 pulse-waveform changes were most affected by the parameters associated with the shape of the smooth muscle tension response and vessel elasticity, providing insight into the physiological mechanisms responsible for observed changes in the pulse-waveform shape. Copyright © 2013 IPEM. All rights reserved.

  14. [Morphological and functional features of circulatory system in retired and active elite athletes].

    PubMed

    Achkasov, E E; Mashkovskiĭ, E V; Bogova, O T; Vulkan, Sh

    2014-01-01

    Regular physical activity over a long period of time increases the output of the cardiovascular system. That leads to development of a normal (physiological) athlete's heart. Bradycardia, cardiac hypertrophy, and arterial hypotension are three major characteristics of a normal athlete's heart. Changes in parameters of cardiovascular system and features of heart remodeling are determined by type, frequency, and duration of a physical activity. Excessive levels of physical activity could result in development of a pathologic athlete's heart, negatively affect hearts metabolism, and increase the risk of both atherosclerosis and myocardial infarction. Autopsy studies have shown that atherosclerosis, which leads to development of an ischemic heart disease, is often found in both young and elderly athletes. 56% of sudden deaths in all athletes were due to cardiovascular problems. Reports of ischemic heart disease in athletes of all ages have increased over the past few years. Echocardiographic features and clinical outcomes of stable angina and myocardial infarction in retired professional athletes are not well studied. Further studies are needed to improve diagnosis, prevention, treatment, and rehabilitation in elite athletes with ischemic heart disease.

  15. Teaching Bio-inspired design using heart and circulatory system as a model

    NASA Astrophysics Data System (ADS)

    Gharib, Morteza

    2007-11-01

    Cardiovasculr system is an open book of design for an engineer searching for innovation in the particular area of efficient fluid transport. But the routs of technology transfer from nature's technology to engineering science are not always so obvious. The main challenge is how to train our future students to find these hidden innovations and apply them based on sound engineering and scientific principles. As part of a 3 quarter course at Caltech that is called ``Physiology for Bioengineers,'' we try to discuss examples of such cases by introducing students to the critical thinking that is required for model development. In this talk, I will give two examples from the third quarter of this course where students are asked to develop a physics-based model to describe the efficient pumping of blood in embryonic and adult hearts.

  16. Functional anatomy of the ocular circulatory system: vascular corrosion casts of the cetacean eye.

    PubMed

    Ninomiya, Hiroyoshi; Yoshida, Emi

    2007-01-01

    To examine the functional anatomy of the ocular circulation in four bottlenose dolphins (Tursiops truncatus) and five melon-headed whales (Peponocephala electra). Eyes were obtained postmortem from whales that died while in captivity and/or were found beached. Specimens from whales were investigated using scanning electron microscopy (SEM) of vascular corrosion casts and histology. The thermal characteristics of live dolphin eyes were measured using an infrared imaging system. The whale eye receives its primary blood supply from the ophthalmic rete, which extends just behind the eyeball. The ophthalmic rete diverges from the basilar rete and the cervical rete via the posterior thoracic artery. The iris and ciliary processes are supplied by iridic arteries via the major arterial circle that is located around the iris edge. The retinal vessels show the holangiotic type. Choroidal arteries run in parallel arrays so as to interdigitate the densely packed choroidal veins. The venules in the conjunctival fold and palpebral conjunctiva form a well-developed venous plexus. Thermographic examination revealed that the eye shows a substantially higher degree of thermal emission than adjacent skin areas. The cetacean eye is characterized by a unique vascular pattern and multivessel plexuses, which are quite different from those of terrestrial mammals. This suggests that the ocular vasculature might function as a thermoregulatory system so that the appropriate operating temperature for the photoreceptors can be maintained in a deep and cold aquatic environment. The distinctive plexuses in the orbit might also be for pooling blood in the eye to conserve oxygen during dives. The ophthalmic rete might play a role in a pressure-damping effect on cetacean ocular circulation as well.

  17. Numerical modeling of the fetal blood flow in the placental circulatory system

    NASA Astrophysics Data System (ADS)

    Shannon, Alexander; Gallucci, Sergio; Mirbod, Parisa

    2015-11-01

    The placenta is a unique organ of exchange between the growing fetus and the mother. It incorporates almost all functions of the adult body, acting as the fetal lung, digestive and immune systems, to mention a few. The exchange of oxygen and nutrients takes place at the surface of the villous tree. Using an idealized geometry of the fetal villous trees in the mouse placenta, in this study we performed 3D computational analysis of the unsteady fetal blood flow, gas, and nutrient transport over the chorionic plate. The fetal blood was treated as an incompressible Newtonian fluid, and the oxygen and nutrient were treated as a passive scalar dissolved in blood plasma. The flow was laminar, and a commercial CFD code (COMSOL Multiphysics) has been used for the simulation. COMSOL has been selected because it is multi-physics FEM software that allows for the seamless coupling of different physics represented by partial differential equations. The results clearly illustrate that the specific branching pattern and the in-plane curvature of the fetal villous trees affect the delivery of blood, gas and nutrient transport to the whole placenta.

  18. The effects of carbon disulfide and ethanol on the circulatory system of rats.

    PubMed

    Morvai, Veronika; Szakmáry, Eva; Ungváry, György

    2005-05-28

    Carbon disulfide exerted adverse effects on the structure or hemodynamics of the cardiovascular system, and whether ethanol exposure modifies the cardiovascular effect of carbon disulfide, was examined. Male Sprague-Dawley rats were used in the study. Animals in the control and ethanol groups drank water containing 5% sugar, or 10% ethanol in addition to 5% sugar, respectively, for 14 wk. Sepatare animals inhaled 700 mg/m3 of carbon disulfide for 6 h daily. Carbon disulfide treatment did not affect the food and fluid consumption of the animals, while this gas decreased body mass gain. CS2 increased arterial blood pressure and cardiac index, decreased their cardiac output, the fraction of the cardiac output, and blood flow for the kidneys and the lungs, and increased the relative heart, liver, and kidneys mass and the vascular resistance of the brain, lungs, and kidneys. Ethanol decreased the food and fluid consumption and body mass gain of the animals, the fraction of the cardiac output for the kidneys, and the vascular resistance of the liver, while it increased the blood flow of the brain and liver. Simultaneous administration of carbon disulfide and ethanol decreased the heart rate and increased the QRS duration. Significant interaction was found between the effect in case of heart rate, PQ distance, and QRS duration; carbon disulfide significantly increased the minimal-moderate effect of ethanol on all three parameters. With histological examinations no pathologic alterations were found in the organs studied. It was concluded that the early hemodynamic changes produced by carbon disulfide may play a significant role in the pathomechanism of the effects of the substance (hypertension, damage to the myocardium and kidneys). On the other hand, a potentiating interaction of carbon disulfide was expected with the effects of ethanol, at the administered concentration and dose in the study.

  19. Changes in the levels of coenzyme Q homologues, alpha-tocopherol and malondialdehyde in human tissue during the course of circulatory shock.

    PubMed

    Corbucci, G G; Gasparetto, A; Antonelli, M; Bufi, M; De Blasi, R A

    1986-01-01

    Following our previous findings on mitochondrial oxidative damage during the course of circulatory shock in human muscular tissue, in the present work we examined the pathogenic connections between the electron-transport-chain enzymic activity and the ubiquinone metabolism. The effects of the oxidative damage on the alpha-tocopherol content and malondialdehyde (MDA) levels were also studied. The results reveal an involvement of cytochrome oxidase and coenzyme Q10 in the oxidative damage due to shock; alpha-tocopherol seems to show a particularly increased antioxidant activity contemporary with the marked increase in MDA levels. These findings suggest that the significant fall in the mitochondrial oxidative capacity could generate an oxygen free-radical production with subsequent peroxidative damage of the mitochondrial inner-membrane bilayer.

  20. Development and hydrodynamic evaluation of a novel inflow cannula in a mechanical circulatory support system for bridge to decision.

    PubMed

    Sumikura, Hirohito; Toda, Koichi; Takewa, Yoshiaki; Tsukiya, Tomonori; Ohnuma, Kentaro; Sasagawa, Mitsuo; Watanabe, Fumikazu; Ugawa, Junichi; Taenaka, Yoshiyuki; Tatsumi, Eisuke

    2011-08-01

    Recent progress in the development of implantable rotary blood pumps realized long-term mechanical circulatory support (MCS) for bridge to transplant, bridge to recovery, or a destination therapy. Meanwhile, a short-term MCS system is becoming necessary for bridge to decision. We developed a novel inflow cannula for the short-term MCS system, which gives sufficient bypass flow with minimal invasion at insertion, and evaluated its hydrodynamic characteristics. The novel inflow cannula, named the Lantern cannula, is made of elastic silicone reinforced with metal wires. The cannula tip has six slits on the side. This cannula tip can be extended to the axial direction by using an introducer and can be reduced in diameter, and the Lantern cannula enables easy insertion into the left ventricle apex with minimal invasion. The sufficient bypass flow rate can be obtained due to low pressure loss. Moreover, this Lantern shape also resists suction complication around the cannula tip. The pressure loss through the Lantern cannula was measured using a mock circulation and compared with two commercially available venous cannulae (Sarns4882, Terumo, Tokyo, Japan and Stockert V122-28, Sorin Group, Tokyo, Japan), which have almost same diameter as the Lantern cannula. Moreover, the flow patterns around the cannula tip were numerically analyzed by computational fluid dynamics (CFD). Acute animal experiment was also performed to confirm the practical effectiveness of the Lantern cannula. The pressure loss of the Lantern cannula was the lowest compared with those of the commercially available venous cannulae in in vitro experiment. CFD analysis results demonstrated that the Lantern cannula has low pressure loss because of wide inflow orifice area and a bell mouth, which were formed via Lantern shape. The highest bypass flow was obtained in the Lantern cannula because of the low pressure loss under pulsatile condition in in vivo experiments. The Lantern cannula demonstrated superior

  1. AC Electrothermal Circulatory Pumping Chip for Cell Culture.

    PubMed

    Lang, Qi; Wu, Yanshuang; Ren, Yukun; Tao, Ye; Lei, Lei; Jiang, Hongyuan

    2015-12-09

    Herein we describe a novel AC electrothermal (ACET) fluidic circulatory pumping chip to overcome the challenge of fluid-to-tissue ratio for "human-on-a-chip" cell culture systems. To avoid the deleterious effects of Joule heating and electric current on sample cells, a rectangular microchannel was designed with distantly separated regions for pumping and cell culture. Temperature variations were examined using a commercial thermocouple sensor to detect temperature values in both pumping and culture regions. To generate a sufficient ACET circulatory pumping rate, 30 pairs of asymmetrical electrodes were employed in the pumping region; generated ACET velocity was measured by fluorescent microparticle image velocimetry. The benefits of our pumping chip were demonstrated by culturing human embryonic kidney cells (HEK293T) and human colon carcinoma cells (SW620) for 72 h with an energized voltage of 3 V and 10 MHz. Cells grew and proliferated well, implying our ACET circulatory pumping chip has great potential for cell culture and tissue engineering applications.

  2. Life expectancy and death by diseases of the circulatory system in patients with bipolar disorder or schizophrenia in the Nordic countries.

    PubMed

    Laursen, Thomas Munk; Wahlbeck, Kristian; Hällgren, Jonas; Westman, Jeanette; Ösby, Urban; Alinaghizadeh, Hassan; Gissler, Mika; Nordentoft, Merete

    2013-01-01

    Excess mortality from diseases and medical conditions (natural death) in persons with psychiatric disorders has been extensively reported. Even in the Nordic countries with well-developed welfare systems, register based studies find evidence of an excess mortality. In recent years, cardiac mortality and death by diseases of the circulatory system has seen a decline in all the Nordic countries, but a recent paper indicates that women and men in Denmark, Finland, and Sweden, who had been hospitalised for a psychotic disorder, had a two to three-fold increased risk of dying from a cardiovascular disease. The aim of this study was to compare the mortality by diseases of the circulatory system among patients with bipolar disorder or schizophrenia in the three Nordic countries Denmark, Sweden, and Finland. Furthermore, the aim was to examine and compare life expectancy among these patients. Cause specific Standardized Mortality Rates (SMRs) were calculated for each specific subgroup of mortality. Life expectancy was calculated using Wiesler's method. The SMR for bipolar disorder for diseases of the circulatory system was approximately 2 in all countries and both sexes. SMR was slightly higher for people with schizophrenia for both genders and in all countries, except for men in Denmark. Overall life expectancy was much lower among persons with bipolar disorder or schizophrenia, with life expectancy being from 11 to 20 years shorter. Our data show that persons in the Nordic countries with schizophrenia or bipolar disorder have a substantially reduced life expectancy. An evaluation of the reasons for these increased mortality rates should be prioritized when planning healthcare in the coming years.

  3. Life Expectancy and Death by Diseases of the Circulatory System in Patients with Bipolar Disorder or Schizophrenia in the Nordic Countries

    PubMed Central

    Laursen, Thomas Munk; Wahlbeck, Kristian; Hällgren, Jonas; Westman, Jeanette; Ösby, Urban; Alinaghizadeh, Hassan; Gissler, Mika; Nordentoft, Merete

    2013-01-01

    Objective Excess mortality from diseases and medical conditions (natural death) in persons with psychiatric disorders has been extensively reported. Even in the Nordic countries with well-developed welfare systems, register based studies find evidence of an excess mortality. In recent years, cardiac mortality and death by diseases of the circulatory system has seen a decline in all the Nordic countries, but a recent paper indicates that women and men in Denmark, Finland, and Sweden, who had been hospitalised for a psychotic disorder, had a two to three-fold increased risk of dying from a cardiovascular disease. The aim of this study was to compare the mortality by diseases of the circulatory system among patients with bipolar disorder or schizophrenia in the three Nordic countries Denmark, Sweden, and Finland. Furthermore, the aim was to examine and compare life expectancy among these patients. Cause specific Standardized Mortality Rates (SMRs) were calculated for each specific subgroup of mortality. Life expectancy was calculated using Wiesler’s method. Results The SMR for bipolar disorder for diseases of the circulatory system was approximately 2 in all countries and both sexes. SMR was slightly higher for people with schizophrenia for both genders and in all countries, except for men in Denmark. Overall life expectancy was much lower among persons with bipolar disorder or schizophrenia, with life expectancy being from 11 to 20 years shorter. Conclusion Our data show that persons in the Nordic countries with schizophrenia or bipolar disorder have a substantially reduced life expectancy. An evaluation of the reasons for these increased mortality rates should be prioritized when planning healthcare in the coming years. PMID:23826212

  4. Development of a Deprivation Index and its relation to premature mortality due to diseases of the circulatory system in Hungary, 1998-2004.

    PubMed

    Juhász, Attila; Nagy, Csilla; Páldy, Anna; Beale, Linda

    2010-05-01

    An association between health and socio-economic status is well known. Based on international and national studies, the aims of this study were to develop a multi-dimensional index at the municipality level, to provide information about socio-economic deprivation in Hungary and to investigate the association between socio-economic status and the spatial distribution of premature mortality due to diseases of the circulatory system. Seven municipality level socio-economic indicators were used from the National Information System of Spatial Development (income, low qualification, unemployment, one-parent families, large families, density of housing and car ownership). After normalisation and standardisation, indicator weights were evaluated using factor analysis. A risk analysis study was conducted using the Rapid Inquiry Facility software to evaluate the association between deprivation and the spatial distribution of premature mortality due to diseases of the circulatory system for the years 1998-2004. Areas of significantly high deprivation were identified in the northeastern, eastern and southwestern parts of Hungary. A statistically significant association was found between premature cardiovascular mortality and deprivation status in both genders. The Deprivation Index is the first composite index at the municipality level in Hungary and includes key factors that affect socio-economic status. The identified association highlighted the fact that inequalities in socio-economic status may reflect the spatial distribution of health status in a population. The results can be used to inform prevention strategies and help plan local health promotion programs aimed at reducing health inequalities.

  5. The blood volumes of the primary and secondary circulatory system in the Atlantic cod Gadus morhua L, using plasma bound Evans Blue and compartmental analysis.

    PubMed

    Skov, P V; Steffensen, J F

    2003-02-01

    The volume of the primary (PCS) and secondary (SCS) circulatory system in the Atlantic cod Gadus morhua was determined using a modified dye dilution technique. Cod (N=10) were chronically cannulated in the second afferent branchial artery with PE-50 tubing. Evans Blue dye was bound to harvested fish plasma at a concentration of 1 mg dye ml(-1) plasma, and injected at a concentration of 1 mg kg(-1) body mass. Serial sampling from the cannula produced a dye dilution curve, which could be described by a double exponential decay equation. Curve analysis enabled the calculation of the primary circulatory and total distribution volume. The difference between these volumes is assumed to be the volume of the SCS. From the dilution curve, it was also possible to calculate flow rates between and within the systems. The results of these experiments suggest a plasma volume in the PCS of 3.42+/-0.89 ml 100 g(-1) body mass, and in the SCS of 1.68+/-0.35 ml 100 g(-1) body mass (mean +/- S.D.) or approximately 50% that of the PCS. Flow rates to the SCS were calculated as 2.7% of the resting cardiac output. There was an allometric relationship between body mass and blood volumes. Increasing condition factor showed a tendency towards smaller blood volumes of the PCS, expressed as percentage body mass, but this was not evident for the volume of the SCS.

  6. Functional integration of the circulatory, immune, and respiratory systems in mosquito larvae: pathogen killing in the hemocyte-rich tracheal tufts.

    PubMed

    League, Garrett P; Hillyer, Julián F

    2016-09-19

    As both larvae and adults, mosquitoes encounter a barrage of immune insults, ranging from microbe-rich communities in larval habitats to ingested blood-borne pathogens in adult blood meals. Given that mosquito adults have evolved an efficient means of eliminating infections in their hemocoel (body cavity) via the coordinated action of their immune and circulatory systems, the goal of the present study was to determine whether such functional integration is also present in larvae. By fluorescently labeling hemocytes (immune cells), pericardial cells, and the heart, we discovered that fourth instar larvae, unlike adults, contain segmental hemocytes but lack the periostial hemocytes that surround the ostia (heart valves) in abdominal segments 2-7. Instead, larvae contain an abundance of sessile hemocytes at the tracheal tufts, which are respiratory structures that are unique to larvae, are located in the posterior-most abdominal segment, and surround what in larvae are the sole incurrent openings for hemolymph entry into the heart. Injection of fluorescent immune elicitors and bacteria into the larval hemocoel then showed that tracheal tuft hemocytes mount rapid and robust immune responses against foreign insults. Indeed, green fluorescent protein-labeled Escherichia coli flowing with the hemolymph rapidly aggregate exclusively at the tracheal tufts, where they are killed within 24 h post-infection via both phagocytosis and melanization. Together, these findings show that the functional integration of the circulatory, respiratory, and immune systems of mosquitoes varies drastically across life stages.

  7. Combined television viewing and computer use and mortality from all-causes and diseases of the circulatory system among adults in the United States.

    PubMed

    Ford, Earl S

    2012-01-23

    Watching television and using a computer are increasingly common sedentary behaviors. Whether or not prolonged screen time increases the risk for mortality remains uncertain. Mortality for 7,350 adults aged ≥ 20 years who participated in the National Health and Nutrition Examination Survey during 1999-2002 and were followed through 2006 was examined. Participants were asked a single question about the amount of time they spent watching television or videos or using a computer during the past 30 days. During a median follow-up of 5.8 years, 542 participants died. At baseline, 12.7% of participants reported watching television or using a computer less than 1 h per day, 16.4% did so for 1 h, 27.8% for 2 h, 18.7% for 3 h, 10.9% for 4 h, and 13.5% for 5 or more h. After extensive adjustment, the hazard ratio for all-cause mortality for the top category of exposure was 1.30 (95% confidence interval: 0.82, 2.05). No significant trend across categories of exposure was noted. The amount of screen time was also not significantly related to mortality from diseases of the circulatory system. In the present study, screen time did not significantly predict mortality from all-causes and diseases of the circulatory system.

  8. The Circulatory and Metabolic Responses to Hypoxia in Humans – With Special Reference to Adipose Tissue Physiology and Obesity

    PubMed Central

    Heinonen, Ilkka H. A.; Boushel, Robert; Kalliokoski, Kari K.

    2016-01-01

    Adipose tissue metabolism and circulation play an important role in human health. It is well-known that adipose tissue mass is increased in response to excess caloric intake leading to obesity and further to local hypoxia and inflammatory signaling. Acute exercise increases blood supply to adipose tissue and mobilization of fat stores for energy. However, acute exercise during systemic hypoxia reduces subcutaneous blood flow in healthy young subjects, but the response in overweight or obese subjects remains to be investigated. Emerging evidence also indicates that exercise training during hypoxic exposure may provide additive benefits with respect to many traditional cardiovascular risk factors as compared to exercise performed in normoxia, but unfavorable effects of hypoxia have also been documented. These topics will be covered in this brief review dealing with hypoxia and adipose tissue physiology. PMID:27621722

  9. Pulsatile-flow mechanical circulatory support (MCS) as a bridge to transplantation or recovery. Single-centre experience with the POLCAS system in 2014.

    PubMed

    Kuśmierczyk, Mariusz; Kuć, Mateusz; Szymański, Jarosław; Juraszek, Andrzej; Kołsut, Piotr; Kuśmierski, Krzysztof; Zieliński, Tomasz; Sobieszczańska-Małek, Małgorzata; Sitkowska-Rysiak, Ewa

    2015-09-01

    Mechanical circulatory support (MCS) is a recognised method of treatment for patients with end-stage chronic or acute heart failure. The POLCAS pulsatile-flow system has been used in our institution for 15 years. Currently, it is being widely replaced by continuous-flow mechanical circulatory support equipment of the second and third generations (HeartMateII, HeartWare). The MCS presented in this study is associated with a significant risk of complications and its use is increasingly considered controversial. The aim of the study was an evaluation of the results of treatment utilising the POLCAS MCS system at our institution in 2014. The POLCAS system was implanted in 12 patients aged 16-63 years (42 ± 17 years) during a period of 12 months (from January to December, 2014). Full-blown cardiogenic shock was observed in all patients before MCS implantation. Four of the analysed patients (33%) required prior circulatory support with other devices: IABP (n = 2) or ECMO (n = 2). Episodes of cardiac arrest were reported in three patients; three other patients experienced serious arrhythmias, which accelerated the decision to implant MCS. The presented data was retrospectively obtained from the CliniNET system of the Institute of Cardiology. OpenOffice Calc spreadsheet was used for data analysis. Average MCS time was 41 days ± 25 (from 15 to 91 days). Survival until transplantation or explantation was 91.67%. The most frequent complications following the therapy were: cardiac tamponade or bleeding requiring an intervention - 25% (n = 3), renal failure requiring dialysis - 25% (n = 3), ischaemic stroke associated with the MCS - 16.6% (n = 2), bacteraemia - 16.6% (n = 2), and wound infection - 8% (n = 1). No malfunctions of the MCS system were reported. Early survival in patients who completed the MCS therapy, defined as discharge, amounted to 63.6% (n = 7). The POLCAS heart assist system is an effective method of treatment as a bridge to transplantation or recovery in

  10. The heart of a dragon: 3D anatomical reconstruction of the 'scaly-foot gastropod' (Mollusca: Gastropoda: Neomphalina) reveals its extraordinary circulatory system.

    PubMed

    Chen, Chong; Copley, Jonathan T; Linse, Katrin; Rogers, Alex D; Sigwart, Julia D

    2015-01-01

    The 'scaly-foot gastropod' (Chrysomallon squamiferum Chen et al., 2015) from deep-sea hydrothermal vent ecosystems of the Indian Ocean is an active mobile gastropod occurring in locally high densities, and it is distinctive for the dermal scales covering the exterior surface of its foot. These iron-sulfide coated sclerites, and its nutritional dependence on endosymbiotic bacteria, are both noted as adaptations to the extreme environment in the flow of hydrogen sulfide. We present evidence for other adaptations of the 'scaly-foot gastropod' to life in an extreme environment, investigated through dissection and 3D tomographic reconstruction of the internal anatomy. Our anatomical investigations of juvenile and adult specimens reveal a large unganglionated nervous system, a simple and reduced digestive system, and that the animal is a simultaneous hermaphrodite. We show that Chrysomallon squamiferum relies on endosymbiotic bacteria throughout post-larval life. Of particular interest is the circulatory system: Chrysomallon has a very large ctenidium supported by extensive blood sinuses filled with haemocoel. The ctenidium provides oxygen for the host but the circulatory system is enlarged beyond the scope of other similar vent gastropods. At the posterior of the ctenidium is a remarkably large and well-developed heart. Based on the volume of the auricle and ventricle, the heart complex represents approximately 4 % of the body volume. This proportionally giant heart primarily sucks blood through the ctenidium and supplies the highly vascularised oesophageal gland. Thus we infer the elaborate cardiovascular system most likely evolved to oxygenate the endosymbionts in an oxygen poor environment and/or to supply hydrogen sulfide to the endosymbionts. This study exemplifies how understanding the autecology of an organism can be enhanced by detailed investigation of internal anatomy. This gastropod is a large and active species that is abundant in its hydrothermal vent

  11. Radiation and circulatory disease.

    PubMed

    Little, Mark P

    Exposure to therapeutic doses of ionizing radiation is associated with damage to the heart and coronary arteries. However, only recently have studies with high-quality individual dosimetry data allowed this risk to be quantified while also adjusting for concomitant chemotherapy, and medical and lifestyle risk factors. At lower levels of exposure the evidence is less clear. In this article I review radiation-associated risks of circulatory disease in groups treated with radiotherapy for malignant and non-malignant disease, and in occupationally- or environmentally-exposed groups receiving rather lower levels of radiation dose, also for medical diagnostic purposes. Results of a meta-analysis suggest that excess relative risks per unit dose for various types of heart disease do not exhibit statistically significant (p>0.2) heterogeneity between studies. Although there are no marked discrepancies between risks derived from the high-dose therapeutic and medical diagnostic studies and from the moderate/low dose occupational and environmental studies, at least for ischemic heart disease and stroke there are indications of larger risks per unit dose for lower dose rate and fractionated exposures. Risks for stroke and other types of circulatory disease are significantly more variable (p<0.0001), possibly resulting from confounding and effect-modification by well known (but unobserved) risk factors. Adjustment for any of mean dose, dose fractionation or age at exposure results in the residual heterogeneity for cerebrovascular disease becoming non-significant. The review provides strong evidence in support of a causal association between both low and high dose radiation exposure and most types of circulatory disease.

  12. Overview of the 2014 Food and Drug Administration Circulatory System Devices Panel meeting regarding the Lutonix® drug coated balloon.

    PubMed

    Escárcega, Ricardo O; Waksman, Ron

    2014-01-01

    The Lutonix® drug coated balloon (DCB) is a combination device composed of a standard percutaneous angioplasty balloon coated with paclitaxel. Depending on the balloon size, a dose density of 2μg/mm(2) yields a variable total dose raging from 1.5mg to 3.8mg. This drug coated balloon aims to provide improved patency rates in patients with symptomatic femoropopliteal de novo or restenotic atherosclerotic disease. On June 12, 2014, the Food and Drug Administration's (FDA) Circulatory System Devices Panel reviewed the Lutonix DCB premarket approval application (PMA). This PMA application was primarily based on data from the pivotal randomized, controlled and multicenter clinical trial, which compared the Lutonix DCB with PTA. This summary aims to describe the discussions and recommendations made by the advisory panel during the meeting. Based on the Panel's recommendations, it is possible that the FDA will approve this device. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Donation after circulatory death.

    PubMed

    Manara, A R; Murphy, P G; O'Callaghan, G

    2012-01-01

    Donation after circulatory death (DCD) describes the retrieval of organs for the purposes of transplantation that follows death confirmed using circulatory criteria. The persisting shortfall in the availability of organs for transplantation has prompted many countries to re-introduce DCD schemes not only for kidney retrieval but increasingly for other organs with a lower tolerance for warm ischaemia such as the liver, pancreas, and lungs. DCD contrasts in many important respects to the current standard model for deceased donation, namely donation after brain death. The challenge in the practice of DCD includes how to identify patients as suitable potential DCD donors, how to support and maintain the trust of bereaved families, and how to manage the consequences of warm ischaemia in a fashion that is professionally, ethically, and legally acceptable. Many of the concerns about the practice of both controlled and uncontrolled DCD are being addressed by increasing professional consensus on the ethical and legal justification for many of the interventions necessary to facilitate DCD. In some countries, DCD after the withdrawal of active treatment accounts for a substantial proportion of deceased organ donors overall. Where this occurs, there is an increased acceptance that organ and tissue donation should be considered a routine part of end-of-life care in both intensive care unit and emergency department.

  14. Deep hypothermic circulatory arrest

    PubMed Central

    Ziganshin, Bulat A.

    2013-01-01

    Effective cerebral protection remains the principle concern during aortic arch surgery. Hypothermic circulatory arrest (HCA) is entrenched as the primary neuroprotection mechanism since the 70s, as it slows injury-inducing pathways by limiting cerebral metabolism. However, increases in HCA duration has been associated with poorer neurological outcomes, necessitating the adjunctive use of antegrade (ACP) and retrograde cerebral perfusion (RCP). ACP has superseded RCP as the preferred perfusion strategy as it most closely mimic physiological perfusion, although there exists uncertainty regarding several technical details, such as unilateral versus bilateral perfusion, flow rate and temperature, perfusion site, undue trauma to head vessels, and risks of embolization. Nevertheless, we believe that the convenience, simplicity and effectiveness of straight DHCA justifies its use in the majority of elective and emergency cases. The following perspective offers a historical and clinical comparison of the DHCA with other techniques of cerebral protection. PMID:23977599

  15. Whole body hyperthermia, but not skin hyperthermia, accelerates brain and locomotor limb circulatory strain and impairs exercise capacity in humans.

    PubMed

    Trangmar, Steven J; Chiesa, Scott T; Kalsi, Kameljit K; Secher, Niels H; González-Alonso, José

    2017-01-01

    Cardiovascular strain and hyperthermia are thought to be important factors limiting exercise capacity in heat-stressed humans, however, the contribution of elevations in skin (Tsk) versus whole body temperatures on exercise capacity has not been characterized. To ascertain their relationships with exercise capacity, blood temperature (TB), oxygen uptake (V̇O2), brain perfusion (MCA Vmean), locomotor limb hemodynamics, and hematological parameters were assessed during incremental cycling exercise with elevated skin (mild hyperthermia; HYPmild), combined core and skin temperatures (moderate hyperthermia; HYPmod), and under control conditions. Both hyperthermic conditions increased Tsk versus control (6.2 ± 0.2°C; P < 0.001), however, only HYPmod increased resting TB, leg blood flow and cardiac output (Q̇), but not MCA Vmean Throughout exercise, Tsk remained elevated in both hyperthermic conditions, whereas only TB was greater in HYPmod At exhaustion, oxygen uptake and exercise capacity were reduced in HYPmod in association with lower leg blood flow, MCA Vmean and mean arterial pressure (MAP), but similar maximal heart rate and TB The attenuated brain and leg perfusion with hyperthermia was associated with a plateau in MCA and two-legged vascular conductance (VC). Mechanistically, the falling MCA VC was coupled to reductions in PaCO2, whereas the plateau in leg vascular conductance was related to markedly elevated plasma [NA] and a plateau in plasma ATP These findings reveal that whole-body hyperthermia, but not skin hyperthermia, compromises exercise capacity in heat-stressed humans through the early attenuation of brain and active muscle blood flow.

  16. Influence of Mechanical Circulatory Support on Endothelin Receptor Expression in Human Left Ventricular Myocardium from Patients with Dilated Cardiomyopathy (DCM)

    PubMed Central

    Gärtner, Florian; Abraham, Getu; Kassner, Astrid; Baurichter, Daniela; Milting, Hendrik

    2017-01-01

    Background In terminal failing hearts ventricular assist devices (VAD) are implanted as a bridge to transplantation. Endothelin receptor (ETR) antagonists are used for treatment of secondary pulmonary hypertension in VAD patients. However, the cardiac ETR regulation in human heart failure and during VAD support is incompletely understood. Methods In paired left ventricular samples of 12 dilated cardiomyopathy patients we investigated the density of endothelin A (ETA) and B (ETB) receptors before VAD implantation and after device removal. Left ventricular samples of 12 non-failing donor hearts served as control. Receptor quantification was performed by binding of [125I]-ET-1 in the presence of nonselective and ETA selective ETR ligands as competitors. Additionally, the ETR mRNA expression was analyzed using quantitative real-time-PCR. Results The mRNA of ETA but not ETB receptors was significantly elevated in heart failure, whereas total ETR density analyzed by radioligand binding was significantly reduced due to ETB receptor down regulation. ETA and ETB receptor density showed poor correlation to mRNA data (spearman correlation factor: 0.43 and 0.31, respectively). VAD support had no significant impact on the density of both receptors and on mRNA expression of ETA whereas ETB mRNA increased during VAD. A meta-analysis reveals that the ETA receptor regulation in human heart failure appears to depend on non-failing hearts. Conclusions In deteriorating hearts of patients suffering from dilated cardiomyopathy the ETA receptor density is not changed whereas the ETB receptor is down regulated. The mRNA and the proteins of ETA and ETB show a weak correlation. Non-failing hearts might influence the interpretation of ETA receptor regulation. Mechanical unloading of the failing hearts has no impact on the myocardial ETR density. PMID:28095452

  17. Influence of Mechanical Circulatory Support on Endothelin Receptor Expression in Human Left Ventricular Myocardium from Patients with Dilated Cardiomyopathy (DCM).

    PubMed

    Gärtner, Florian; Abraham, Getu; Kassner, Astrid; Baurichter, Daniela; Milting, Hendrik

    2017-01-01

    In terminal failing hearts ventricular assist devices (VAD) are implanted as a bridge to transplantation. Endothelin receptor (ETR) antagonists are used for treatment of secondary pulmonary hypertension in VAD patients. However, the cardiac ETR regulation in human heart failure and during VAD support is incompletely understood. In paired left ventricular samples of 12 dilated cardiomyopathy patients we investigated the density of endothelin A (ETA) and B (ETB) receptors before VAD implantation and after device removal. Left ventricular samples of 12 non-failing donor hearts served as control. Receptor quantification was performed by binding of [125I]-ET-1 in the presence of nonselective and ETA selective ETR ligands as competitors. Additionally, the ETR mRNA expression was analyzed using quantitative real-time-PCR. The mRNA of ETA but not ETB receptors was significantly elevated in heart failure, whereas total ETR density analyzed by radioligand binding was significantly reduced due to ETB receptor down regulation. ETA and ETB receptor density showed poor correlation to mRNA data (spearman correlation factor: 0.43 and 0.31, respectively). VAD support had no significant impact on the density of both receptors and on mRNA expression of ETA whereas ETB mRNA increased during VAD. A meta-analysis reveals that the ETA receptor regulation in human heart failure appears to depend on non-failing hearts. In deteriorating hearts of patients suffering from dilated cardiomyopathy the ETA receptor density is not changed whereas the ETB receptor is down regulated. The mRNA and the proteins of ETA and ETB show a weak correlation. Non-failing hearts might influence the interpretation of ETA receptor regulation. Mechanical unloading of the failing hearts has no impact on the myocardial ETR density.

  18. Teaching Integrative Physiology Using the Quantitative Circulatory Physiology Model and Case Discussion Method: Evaluation of the Learning Experience

    ERIC Educational Resources Information Center

    Rodriguez-Barbero, A.; Lopez-Novoa, J. M.

    2008-01-01

    One of the problems that we have found when teaching human physiology in a Spanish medical school is that the degree of understanding by the students of the integration between organs and systems is rather poor. We attempted to remedy this problem by using a case discussion method together with the Quantitative Circulatory Physiology (QCP)…

  19. Teaching Integrative Physiology Using the Quantitative Circulatory Physiology Model and Case Discussion Method: Evaluation of the Learning Experience

    ERIC Educational Resources Information Center

    Rodriguez-Barbero, A.; Lopez-Novoa, J. M.

    2008-01-01

    One of the problems that we have found when teaching human physiology in a Spanish medical school is that the degree of understanding by the students of the integration between organs and systems is rather poor. We attempted to remedy this problem by using a case discussion method together with the Quantitative Circulatory Physiology (QCP)…

  20. The first organ-based free ontology for arthropods (Ontology of Arthropod Circulatory Systems - OArCS) and its integration into a novel formalization scheme for morphological descriptions.

    PubMed

    Wirkner, Christian S; Göpel, Torben; Runge, Jens; Keiler, Jonas; Klussmann-Fricke, Bastian-Jesper; Huckstorf, Katarina; Scholz, Stephan; Mikó, Istvan; Yoder, Matt; Richter, Stefan

    2017-01-25

    Morphology, the oldest discipline in the biosciences, is currently experiencing a renaissance in the field of comparative phenomics. However, morphological/phenotypic research still suffers on various levels from a lack of standards. This shortcoming, first highlighted as the "linguistic problem of morphology", concerns the usage of terminology but also the need for formalization of morphological descriptions themselves, something of paramount importance not only to the field of morphology but also when it comes to the use of phenotypic data in systematics and evolutionary biology. We therefore argue, that for morphological descriptions, the basis of all systematic and evolutionary interpretations, ontologies need to be utilized which are based exclusively on structural qualities/properties and which in no case include statements about homology and/or function. Statements about homology and function constitute interpretations on a different or higher level. Based on these 'anatomy ontologies', further ontological dimensions (e.g. referring to functional properties or homology) may be exerted for a broad use in evolutionary phenomics. To this end we present the first organ-based ontology for the most species-rich animal group, the Arthropoda. Our Ontology of Arthropod Circulatory Systems (OArCS) contains a comprehensive collection of 383 terms (i.e. sups) tied to 296 concepts (i.e. definitions) collected from the literature on phenotypic aspects of circulatory organ features in arthropods. All of the concepts used in OArCS are based exclusively on structural features, and in the context of the ontology are independent of homology and functional assumptions. We cannot rule out that in some cases, terms are used which in traditional usage and previous accounts might have implied homology and/or function, e.g. heart, sternal artery. Concepts are composed of descriptive elements that are used to classify observed instances into the organizational framework of the

  1. Vascular and Immunobiology of the Circulatory Sphingosine 1-Phosphate Gradient

    PubMed Central

    Yanagida, Keisuke; Hla, Timothy

    2017-01-01

    Vertebrates are endowed with a closed circulatory system, the evolution of which required novel structural and regulatory changes. Furthermore, immune cell trafficking paradigms adapted to the barriers imposed by the closed circulatory system. How did such changes occur mechanistically? We propose that spatial compartmentalization of the lipid mediator sphingosine 1-phosphate (S1P) may be one such mechanism. In vertebrates, S1P is spatially compartmentalized in the blood and lymphatic circulation, thus comprising a sharp S1P gradient across the endothelial barrier. Circulatory S1P has critical roles in maturation and homeostasis of the vascular system as well as in immune cell trafficking. Physiological functions of S1P are tightly linked to shear stress, the key biophysical stimulus from blood flow. Thus, circulatory S1P confinement could be a primordial strategy of vertebrates in the development of a closed circulatory system. This review discusses the cellular and molecular basis of the S1P gradients and aims to interpret its physiological significance as a key feature of the closed circulatory system. PMID:27813829

  2. Vascular and Immunobiology of the Circulatory Sphingosine 1-Phosphate Gradient.

    PubMed

    Yanagida, Keisuke; Hla, Timothy

    2017-02-10

    Vertebrates are endowed with a closed circulatory system, the evolution of which required novel structural and regulatory changes. Furthermore, immune cell trafficking paradigms adapted to the barriers imposed by the closed circulatory system. How did such changes occur mechanistically? We propose that spatial compartmentalization of the lipid mediator sphingosine 1-phosphate (S1P) may be one such mechanism. In vertebrates, S1P is spatially compartmentalized in the blood and lymphatic circulation, thus comprising a sharp S1P gradient across the endothelial barrier. Circulatory S1P has critical roles in maturation and homeostasis of the vascular system as well as in immune cell trafficking. Physiological functions of S1P are tightly linked to shear stress, the key biophysical stimulus from blood flow. Thus, circulatory S1P confinement could be a primordial strategy of vertebrates in the development of a closed circulatory system. This review discusses the cellular and molecular basis of the S1P gradients and aims to interpret its physiological significance as a key feature of the closed circulatory system.

  3. US FDA perspective on regulatory issues affecting circulatory assist devices.

    PubMed

    Sapirstein, Wolf; Chen, Eric; Swain, Julie; Zuckerman, Bram

    2006-11-01

    There has been a rapid development in mechanical circulatory support systems in the decade since the US FDA first approved a mechanical device to provide the circulatory support lacking from a failing heart. Devices are presently approved for marketing by the FDA to replace a failing ventricle, the Ventricular Assist Device or the entire heart, Total Artificial Heart. Contemporaneous with, and permitted by, improvement in technology and design, devices have evolved from units located extracorporeally to paracorporeal systems and totally implanted devices. Clinical studies have demonstrated a parallel improvement in the homeostatic adequacy of the circulatory support provided. Thus, while the circulatory support was initially tolerated for short periods to permit recovery of cardiac function, this technology eventually provided effective circulatory support for increasing periods that permitted the FDA to approve devices for bridging patients in end-stage cardiac failure awaiting transplant and eventually a device for destination therapy where patients in end-stage heart failure are not cardiac transplant candidates. The approved devices have relied on displacement pumps that mimic the pulsatility of the physiological system. Accelerated development of more compact devices that rely on alternative pump mechanisms have challenged both the FDA and device manufacturers to assure that the regulatory requirements for safety and effectiveness are met for use of mechanical circulatory support systems in expanded target populations. An FDA regulatory perspective is reviewed of what can be a potentially critical healthcare issue.

  4. Circulatory responses to hypoxia in experimental myocardial infarction.

    NASA Technical Reports Server (NTRS)

    Schroll, M.; Robison, S. C.; Harrison, D. C.

    1971-01-01

    Three levels of decreased arterial oxygen saturation elicited a graded circulatory response in dogs, manifested by stepwise increases in cardiac output, left ventricular dp/dt, and stroke volume, and decreases in systemic vascular resistance. Responses to similar hypoxia challenges after experimental myocardial infarction were qualitatively similar but quantitatively less. Although the circulatory compensation for hypoxia was less effective after myocardial infarction, no further deterioration of the haemodynamics was noted.

  5. Circulatory responses to hypoxia in experimental myocardial infarction.

    NASA Technical Reports Server (NTRS)

    Schroll, M.; Robison, S. C.; Harrison, D. C.

    1971-01-01

    Three levels of decreased arterial oxygen saturation elicited a graded circulatory response in dogs, manifested by stepwise increases in cardiac output, left ventricular dp/dt, and stroke volume, and decreases in systemic vascular resistance. Responses to similar hypoxia challenges after experimental myocardial infarction were qualitatively similar but quantitatively less. Although the circulatory compensation for hypoxia was less effective after myocardial infarction, no further deterioration of the haemodynamics was noted.

  6. Pathophysiological roles of peroxynitrite in circulatory shock

    PubMed Central

    Szabó, Csaba; Módis, Katalin

    2014-01-01

    Summary Peroxynitrite is a reactive oxidant produced from nitric oxide (NO) and superoxide, which reacts with proteins, lipids and DNA and promotes cytotoxic and pro-inflammatory responses. Here we overview the role of peroxynitrite in various forms of circulatory shock. Immunohistochemical and biochemical evidence demonstrate the production of peroxynitrite in various experimental models of endotoxic and hemorrhagic shock, both in rodents and in large animals. In addition, biological markers of peroxynitrite have been identified in human tissues after circulatory shock. Peroxynitrite can initiate toxic oxidative reactions in vitro and in vivo. Initiation of lipid peroxidation, direct inhibition of mitochondrial respiratory chain enzymes, inactivation of glyceraldehyde-3-phosphate dehydrogenase, inhibition of membrane Na+/K+ ATP-ase activity, inactivation of membrane sodium channels, and other oxidative protein modifications contribute to the cytotoxic effect of peroxynitrite. In addition, peroxynitrite is a potent trigger of DNA strand breakage, with subsequent activation of the nuclear enzyme poly (ADP-ribose) polymerase (PARP), which promotes cellular energetic collapse and cellular necrosis. Additional actions of peroxynitrite that contribute to the pathogenesis of shock include inactivation of catecholamines and catecholamine receptors (leading to vascular failure), endothelial and epithelial injury (leading to endothelial and epithelial hyper-permeability and barrier dysfunction) as well as myocyte injury (contributing to loss of cardiac contractile function). Neutralization of peroxynitrite with potent peroxynitrite decomposition catalysts provides cytoprotective and beneficial effects in rodent and large animal models of circulatory shock. PMID:20523270

  7. Pathophysiological roles of peroxynitrite in circulatory shock.

    PubMed

    Szabó, Csaba; Módis, Katalin

    2010-09-01

    Peroxynitrite is a reactive oxidant produced from nitric oxide and superoxide, which reacts with proteins, lipids, and DNA, and promotes cytotoxic and proinflammatory responses. Here, we overview the role of peroxynitrite in various forms of circulatory shock. Immunohistochemical and biochemical evidences demonstrate the production of peroxynitrite in various experimental models of endotoxic and hemorrhagic shock both in rodents and in large animals. In addition, biological markers of peroxynitrite have been identified in human tissues after circulatory shock. Peroxynitrite can initiate toxic oxidative reactions in vitro and in vivo. Initiation of lipid peroxidation, direct inhibition of mitochondrial respiratory chain enzymes, inactivation of glyceraldehyde-3-phosphate dehydrogenase, inhibition of membrane Na+/K+ ATPase activity, inactivation of membrane sodium channels, and other oxidative protein modifications contribute to the cytotoxic effect of peroxynitrite. In addition, peroxynitrite is a potent trigger of DNA strand breakage, with subsequent activation of the nuclear enzyme poly(ADP-ribose) polymerase, which promotes cellular energetic collapse and cellular necrosis. Additional actions of peroxynitrite that contribute to the pathogenesis of shock include inactivation of catecholamines and catecholamine receptors (leading to vascular failure) and endothelial and epithelial injury (leading to endothelial and epithelial hyperpermeability and barrier dysfunction), as well as myocyte injury (contributing to loss of cardiac contractile function). Neutralization of peroxynitrite with potent peroxynitrite decomposition catalysts provides cytoprotective and beneficial effects in rodent and large-animal models of circulatory shock.

  8. [Perioperative respiratory and circulatory management for chronic kidney disease].

    PubMed

    Arai, Masayasu

    2013-11-01

    To avoid perioperative cardiac complications and deterioration of renal function in chronic kidney disease (CKD), anesthesiologists are required to manage respiration and circulation properly. Three mechanisms are considered to worsen renal function during inappropriate mechanical ventilation; first, hypercapnia or hypoxemia, second, unstable systemic hemodynamic, and third, systemic inflammatory mediators derived from pulmonary biotrauma. Many circulatory problems are present in CKD patients, for example, hypertension, cardiac hypertrophy, cardiomyopathy, ischemic heart disease, arterial sclerotic valve disease, salt and water retention etc. Blood pressure in CKD patients should be controlled properly before surgery. Renal blood flow and renal perfusion pressure should be maintained by aggressive fluid therapy to avoid perioperative acute kidney injury (AKI) on CKD, while cardiac congestion should also be avoided. Perioerative renal protective effects of human atrial natriuretic peptide (hANP) on CKD still needs further investigation. Appropriate hemodynamic monitoring, including direct arterial pressure, left ventricular preload, intravascular volume and cardiac output could be helpful for anesthesiologists to manage CKD patients safely. In the area of CKD and anesthesia, there is lack of evidence in respiratory and circulatory strategies. Prospective studies in these aspects are required in the future.

  9. The Abdominal Circulatory Pump

    PubMed Central

    Aliverti, Andrea; Bovio, Dario; Fullin, Irene; Dellacà, Raffaele L.; Lo Mauro, Antonella; Pedotti, Antonio; Macklem, Peter T.

    2009-01-01

    Blood in the splanchnic vasculature can be transferred to the extremities. We quantified such blood shifts in normal subjects by measuring trunk volume by optoelectronic plethysmography, simultaneously with changes in body volume by whole body plethysmography during contractions of the diaphragm and abdominal muscles. Trunk volume changes with blood shifts, but body volume does not so that the blood volume shifted between trunk and extremities (Vbs) is the difference between changes in trunk and body volume. This is so because both trunk and body volume change identically with breathing and gas expansion or compression. During tidal breathing Vbs was 50–75 ml with an ejection fraction of 4–6% and an output of 750–1500 ml/min. Step increases in abdominal pressure resulted in rapid emptying presumably from the liver with a time constant of 0.61±0.1SE sec. followed by slower flow from non-hepatic viscera. The filling time constant was 0.57±0.09SE sec. Splanchnic emptying shifted up to 650 ml blood. With emptying, the increased hepatic vein flow increases the blood pressure at its entry into the inferior vena cava (IVC) and abolishes the pressure gradient producing flow between the femoral vein and the IVC inducing blood pooling in the legs. The findings are important for exercise because the larger the Vbs the greater the perfusion of locomotor muscles. During asystolic cardiac arrest we calculate that appropriate timing of abdominal compression could produce an output of 6 L/min. so that the abdominal circulatory pump might act as an auxiliary heart. PMID:19440240

  10. Temporal trends in mortality from diseases of the circulatory system after treatment for Hodgkin lymphoma: a population-based cohort study in Sweden (1973 to 2006).

    PubMed

    Eloranta, Sandra; Lambert, Paul C; Sjöberg, Jan; Andersson, Therese M L; Björkholm, Magnus; Dickman, Paul W

    2013-04-10

    Hodgkin lymphoma (HL) survival in Sweden has improved dramatically over the last 40 years, but little is known about the extent to which efforts aimed at reducing long-term treatment-related mortality have contributed to the improved prognosis. We used population-based data from Sweden to estimate the contribution of treatment-related mortality caused by diseases of the circulatory system (DCS) to temporal trends in excess HL mortality among 5,462 patients diagnosed at ages 19 to 80 between 1973 and 2006. Flexible parametric survival models were used to estimate excess mortality. In addition, we used recent advances in statistical methodology to estimate excess mortality in the presence of competing causes of death. Excess DCS mortality within 20 years after diagnosis has decreased continually since the mid-1980s and is expected to further decrease among patients diagnosed in the modern era. Age at diagnosis and sex were important predictors for excess DCS mortality, with advanced age and male sex being associated with higher excess DCS mortality. However, when accounting for competing causes of death, we found that excess DCS mortality constitutes a relatively small proportion of the overall mortality among patients with HL in Sweden. Excess DCS mortality is no longer a common source of mortality among Swedish patients with HL. The main causes of death among long-term survivors today are causes other than HL, although other (non-DCS) excess mortality also persists for as long as 20 years after diagnosis, particularly among older patients.

  11. Combination of optoacoustics and ultrasound imaging for non-invasive, rapid assessment, and management of circulatory shock

    NASA Astrophysics Data System (ADS)

    Petrov, Yuriy; Petrov, Irene Y.; Esenaliev, Rinat O.; Kinsky, Michael; Prough, Donald S.

    2011-03-01

    We developed a noninvasive, optoacoustic diagnostic platform for monitoring of multiple physiologic variables in inpatients and outpatients. One of the most important applications of this platform is noninvasive, rapid assessment and management of circulatory shock, a common condition in critically ill patients. At present, monitoring of circulatory shock requires measurement of central venous blood oxygenation using invasive procedures such as insertion of catheters in central veins. Hemoglobin saturation below 70% in central veins indicates circulatory shock that requires immediate treatment. We built a portable optoacoustic system for noninvasive measurement of central venous oxygenation. In this study we used the optoacoustic system and clinical ultrasound imaging systems for rapid optoacoustic probing of these veins. The optoacoustic system utilizes a custom-made, sensitive optoacoustic probe that was developed in our laboratory for monitoring of blood oxygenation in deep blood vessels. The studies were performed in human subjects with different geometry (depth, size) of the veins. The ultrasound imaging systems permitted rapid identification of specific blood vessels for optoacoustic probing. We developed a novel algorithm for continuous, realtime, and precise measurement of blood oxygenation in blood vessels. Precision of central venous oxygenation measurement obtained in the study was very high: 1%. Our results indicate that the combination of optoacoustics and ultrasound imaging systems can provide more rapid and accurate assessment and management of the circulatory shock.

  12. Dynamics of Short-Term Phosphorus Uptake by Intact Mycorrhizal and Non-mycorrhizal Maize Plants Grown in a Circulatory Semi-Hydroponic Cultivation System.

    PubMed

    Garcés-Ruiz, Mónica; Calonne-Salmon, Maryline; Plouznikoff, Katia; Misson, Coralie; Navarrete-Mier, Micaela; Cranenbrouck, Sylvie; Declerck, Stéphane

    2017-01-01

    A non-destructive cultivation system was developed to study the dynamics of phosphorus (Pi) uptake by mycorrhizal and non-mycorrhizal maize plantlets. The system consisted of a plant container connected via silicon tubes to a glass bottle containing a nutrient solution supplemented with Pi. The nutrient solution is pumped with a peristaltic pump to the upper part of the container via the silicon tubes and the solution percolate through the plantlet container back into the glass bottle. Pi is sampled from the glass bottle at regular intervals and concentration evaluated. Maize plantlets were colonized by the AMF Rhizophagus irregularis MUCL 41833 and Pi uptake quantified at fixed intervals (9, 21, and 42 h) from the depletion of the Pi in the nutrient solution flowing through the plantlets containers. Plants and fungus grew well in the perlite substrate. The concentration of Pi in the bottles followed an almost linear decrease over time, demonstrating a depletion of Pi in the circulating solution and a concomitant uptake/immobilization by the plantlet-AMF associates in the containers. The Pi uptake rate was significantly increased in the AMF-colonized plantlets (at 9 and 21 h) as compared to non-colonized plantlets, although no correlation was noticed with plant growth or P accumulation in shoots. The circulatory semi-hydroponic cultivation system developed was adequate for measuring Pi depletion in a nutrient solution and by corollary Pi uptake/immobilization by the plant-AMF associates. The measurements were non-destructive so that the time course of Pi uptake could be monitored without disturbing the growth of the plant and its fungal associate. The system further opens the door to study the dynamics of other micro and macro-nutrients as well as their uptake under stressed growth conditions such as salinity, pollution by hydrocarbon contaminants or potential toxic elements.

  13. A mock circulatory system to assess the performance of continuous-flow left ventricular assist devices (LVADs): does axial flow unload better than centrifugal LVAD?

    PubMed

    Sénage, Thomas; Février, Dorothée; Michel, Magali; Pichot, Emmanuel; Duveau, Daniel; Tsui, Steven; Trochu, Jean Noel; Roussel, Jean Christian

    2014-01-01

    Hemodynamic performances comparisons between different types of left ventricular assist devices (LVADs) remain difficult in a clinical context. The aim of this study was to create an experimental model to assess and compare two types of LVAD under hemodynamic conditions that simulated physical effort and pulmonary hypertension. An experimental mock circulatory system was created to simulate the systemic and pulmonary circulations and consisted of pulsatile left and right cardiac simulators (cardiowest pump), air/water tanks to model compliances, and tubes to model the venous and arterial resistances. Two types of continuous-flow ventricular assist devices were connected to this pulsated model: an axial flow pump, Heartmate II (HTM II), and a centrifugal pump, VentrAssist (VTA). The hemodynamic conditions at rest and during exercise were replicated. Mean aortic pressures were not significantly different at rest and during effort but mean flow under maximum pump speed was higher with HTM II (13 L vs. 10 L, p = 0.02). Left atrial pressure was lower at rest and during effort for the HTM II (11 mm Hg vs. 3 mm Hg, p = 0.02 and 9 mm Hg vs. 2 mm Hg, p = 0.008) than with the VTA, but with greater risk of left-ventricle suck-down for the axial flow. Power consumption for a similar flow was lower with the VTA during rest (4.7 W vs. 6.9 W, p = 0.002) and during effort (4.3 W vs. 6.6 W, p = 0.008). In case of high pulmonary vascular resistance with preserved right ventricular function, lower right ventricular pressure was obtained with HTM II (21 mm Hg vs. 28 mm Hg, p = 0.03). Observed results are in favor of a better discharge of the left and right cavities with the HTM II compared to the VTA yet with a higher risk of left cavity collapse occurrence.

  14. Risks of circulatory diseases among Mayak PA workers with radiation doses estimated using the improved Mayak Worker Dosimetry System 2008.

    PubMed

    Moseeva, Maria B; Azizova, Tamara V; Grigoryeva, Evgenia S; Haylock, Richard

    2014-05-01

    The new Mayak Worker Dosimetry System 2008 (MWDS-2008) was published in 2013 and supersedes the Doses-2005 dosimetry system for Mayak Production Association (PA) workers. It provides revised external and internal dose estimates based on the updated occupational history data. Using MWDS-2008, a cohort of 18,856 workers first employed at one of the main Mayak PA plants during 1948-1972 and followed up to 2005 was identified. Incidence and mortality risks from ischemic heart disease (IHD) (International Classification of Diseases (ICD)-9 codes 410-414) and from cerebrovascular diseases (CVD) (ICD-9 codes 430-438) were examined in this cohort and compared with previously published risk estimates in the same cohort based on the Doses-2005 dosimetry system. Significant associations were observed between doses from external gamma-rays and IHD and CVD incidence and also between internal doses from alpha-radiation and IHD mortality and CVD incidence. The estimates of excess relative risk (ERR)/Gy were consistent with those estimates from the previous studies based on Doses-2005 system apart from the relationship between CVD incidence and internal liver dose where the ERR/Gy based on MWDS-2008 was just over three times higher than the corresponding estimate based on Doses-2005 system. Adjustment for smoking status did not show any effect on the estimates of risk from internal alpha-particle exposure.

  15. [Peculiarities of systemic on regional circulatory dynamics at a pseudoexfoliative syndrome and pseudoexfoliative glaucoma (review of literature)].

    PubMed

    Brezhnev, A Iu; Kuroedov, A V; Aleksandrov, A S

    2010-05-01

    The article presents results of searches, devoted to haemodynamic damages against wide-spread ophthalmo-pathology--pseudoexfoliative syndrome and pseudoexfoliative glaucoma. Changes, appearing on different levels, confirm hypothesis about systemic character of the disease and prove the necessity of further examination of role of syndrome in development of different forms of vascular disease.

  16. The influence of the winter North Atlantic Oscillation index on hospital admissions through diseases of the circulatory system in Lisbon, Portugal

    NASA Astrophysics Data System (ADS)

    Almendra, Ricardo; Santana, Paula; Vasconcelos, João; Silva, Giovani; Gonçalves, Fábio; Ambrizzi, Tércio

    2017-02-01

    The aim of this paper is to analyze the relationship between North Atlantic Oscillation (NAO), meteorological variables, air pollutants, and hospital admissions due to diseases of circulatory systems in Lisbon (Portugal) during winter months (2003-2012). This paper is one of the few studies analyzing the impact of NAO on health through its influence on thermal stress and air pollution and is the first to be conducted in Lisbon. This study uses meteorological data (synthetized into a thermal comfort index), air pollutant metrics, and the NAO index (all clustered in 10-day cycles to overcome daily variability of the NAO index). The relationship between morbidity, thermal comfort index, NAO index, and air pollutants was explored through several linear models adjusted to seasonality through a periodic function. The possible indirect effect between the NAO index and hospital admissions was tested, assuming that NAO (independent variable) is affecting hospital admissions (outcome variable) through thermal discomfort and/or pollution levels (tested as individual mediators). This test was conducted through causal mediation analysis and adjusted for seasonal variation. The results from this study suggest a possible indirect relationship between NAO index and hospital admissions. Although NAO is not significantly associated with hospital admissions, it is significantly associated with CO, PM2.5, NO, and SO2 levels, which in turn increase the probability of hospitalization. The discomfort index (built with temperature and relative humidity) is significantly associated with hospital admissions, but its variability is not explained by the NAO index. This study highlights the impacts of the atmospheric circulation patterns on health. Furthermore, understanding the influence of the atmospheric circulation patterns can support the improvement of the existing contingency plans.

  17. The influence of the winter North Atlantic Oscillation index on hospital admissions through diseases of the circulatory system in Lisbon, Portugal.

    PubMed

    Almendra, Ricardo; Santana, Paula; Vasconcelos, João; Silva, Giovani; Gonçalves, Fábio; Ambrizzi, Tércio

    2017-02-01

    The aim of this paper is to analyze the relationship between North Atlantic Oscillation (NAO), meteorological variables, air pollutants, and hospital admissions due to diseases of circulatory systems in Lisbon (Portugal) during winter months (2003-2012). This paper is one of the few studies analyzing the impact of NAO on health through its influence on thermal stress and air pollution and is the first to be conducted in Lisbon. This study uses meteorological data (synthetized into a thermal comfort index), air pollutant metrics, and the NAO index (all clustered in 10-day cycles to overcome daily variability of the NAO index). The relationship between morbidity, thermal comfort index, NAO index, and air pollutants was explored through several linear models adjusted to seasonality through a periodic function. The possible indirect effect between the NAO index and hospital admissions was tested, assuming that NAO (independent variable) is affecting hospital admissions (outcome variable) through thermal discomfort and/or pollution levels (tested as individual mediators). This test was conducted through causal mediation analysis and adjusted for seasonal variation. The results from this study suggest a possible indirect relationship between NAO index and hospital admissions. Although NAO is not significantly associated with hospital admissions, it is significantly associated with CO, PM2.5, NO, and SO2 levels, which in turn increase the probability of hospitalization. The discomfort index (built with temperature and relative humidity) is significantly associated with hospital admissions, but its variability is not explained by the NAO index. This study highlights the impacts of the atmospheric circulation patterns on health. Furthermore, understanding the influence of the atmospheric circulation patterns can support the improvement of the existing contingency plans.

  18. A Multi-Scale Model of the Circulatory System for the Study of Left Ventricular Assist Devices

    NASA Astrophysics Data System (ADS)

    Gohean, J. R.; Moser, R. D.; Bazilevs, Y.; Hughes, T. J. R.

    2006-11-01

    A computer model of the cardiovascular system has been developed to study the hemodynamic effects of a non-pulsatile axial flow left ventricular assist device (LVAD). The model is multi-scale and consists of a distributed quasi-one-dimensional arterial tree, based on integrated Navier-Stokes with a pressure/area state equation representing the compliance of the arteries; and lumped parameter models for the systemic return, pulmonary circulation, coronary circulation, and heart. Physiologically consistent aortic pressure and flow histories have been obtained by including a dynamic aortic valve model that allows back-flow by representing leaflet motion. In addition, a three-dimensional finite element model of the aorta with nonlinear elastic arterial walls can be integrated with the quasi-one-dimensional and lumped parameter models, with the lower fidelity models providing boundary conditions for the detailed model. The three dimensional model allows investigation of the detailed flow characteristics induced by the LVAD. The effect of an LVAD and its implant configuration on the hemodynamics of the cardiovascular system and coronary perfusion are studied for various patient conditions and levels of assist.

  19. Microvascular Fluid Resuscitation in Circulatory Shock.

    PubMed

    Hamlin, Shannan K; Strauss, Penelope Z; Chen, Hsin-Mei; Christy, LaDonna

    2017-06-01

    The microcirculation is responsible for blood flow regulation and red blood cell distribution throughout individual organs. Patients with circulatory shock have acute failure of the cardiovascular system in which there is insufficient delivery of oxygen to meet metabolic tissue requirements. All subtypes of shock pathophysiology have a hypovolemic component. Fluid resuscitation guided by systemic hemodynamic end points is a common intervention. Evidence shows that microcirculatory shock persists even after optimization of macrocirculatory hemodynamics. The ability for nurses to assess the microcirculation at the bedside in real-time during fluid resuscitation could lead to improved algorithms designed to resuscitate the microcirculation. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Structures with Reconfigurable Circulatory Systems

    DTIC Science & Technology

    2008-05-16

    precedent for the general concept and aims, it was naturally disappointing not to be the first to report this chemistry. In parallel with the...polymerization in reverse. Thiol compounds, such as glutathione, cysteine and homocysteine are a natural reservoir of reductive capacities of the cells...Cysteine, an amino acid, is a critical substrate in biosynthesis of proteins, glutathione, taurine sulfate and the exceptionally metabolically active

  1. Mechanical circulatory support in pediatrics.

    PubMed

    Steffen, Robert J; Miletic, Kyle G; Schraufnagel, Dean P; Vargo, Patrick R; Fukamachi, Kiyotaka; Stewart, Robert D; Moazami, Nader

    2016-05-01

    End-stage heart failure affects thousands of children yearly and mechanical circulatory support is used at many points in their care. Extracorporeal membrane oxygenation supports both the failing heart and lungs, which has led to its use as an adjunct to cardiopulmonary resuscitation as well as in post-operative cardiogenic shock. Continuous-flow ventricular assist devices (VAD) have replaced pulsatile-flow devices in adults and early studies have shown promising results in children. The Berlin paracorporeal pulsatile VAD recently gained U.S. Food and Drug Administration approval and remains the only VAD approved in pediatrics. Failing univentricular hearts and other congenitally corrected lesions are new areas for mechanical support. Finding novel uses, improving durability, and minimizing complications are areas of growth in pediatric mechanical circulatory support.

  2. Overview of the 2011 food and drug administration's circulatory system devices panel of the medical devices advisory committee meeting on the Zilver® PTX® drug-eluting peripheral stent.

    PubMed

    Dvir, Danny; Torguson, Rebecca; Waksman, Ron

    2012-01-01

    Zilver® PTX® (Cook Medical, Bloomington, IN) is a self-expanding nitinol drug-eluting stent with a polymer-free paclitaxel coating on its outer surface. The stent aims to provide improved treatment for patients with symptomatic peripheral arterial disease in the above-the-knee femoropopliteal arteries. On October 13, 2011, the Food and Drug Administration's (FDA) Circulatory System Devices Panel reviewed the Zilver PTX premarket approval application. This summary aims to describe the discussions and recommendations made during the meeting. Based on the Panel's recommendations, it is anticipated that the device will be approved by the FDA. Copyright © 2012. Published by Elsevier Inc.

  3. Mass Spectrometry Based Metabolomics Comparison of Liver Grafts from Donors after Circulatory Death (DCD) and Donors after Brain Death (DBD) Used in Human Orthotopic Liver Transplantation

    PubMed Central

    Laing, Richard; Kirwan, Jennifer; Silva, Michael A.; Richards, Douglas A.; Murphy, Nick; Mirza, Darius F.; Viant, Mark R.

    2016-01-01

    Use of marginal liver grafts, especially those from donors after circulatory death (DCD), has been considered as a solution to organ shortage. Inferior outcomes have been attributed to donor warm ischaemic damage in these DCD organs. Here we sought to profile the metabolic mechanisms underpinning donor warm ischaemia. Non-targeted Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry metabolomics was applied to biopsies of liver grafts from donors after brain death (DBD; n = 27) and DCD (n = 10), both during static cold storage (T1) as well as post-reperfusion (T2). Furthermore 6 biopsies from DBD donors prior to the organ donation (T0) were also profiled. Considering DBD and DCD together, significant metabolic differences were discovered between T1 and T2 (688 peaks) that were primarily related to amino acid metabolism, meanwhile T0 biopsies grouped together with T2, denoting the distinctively different metabolic activity of the perfused state. Major metabolic differences were discovered between DCD and DBD during cold-phase (T1) primarily related to glucose, tryptophan and kynurenine metabolism, and in the post-reperfusion phase (T2) related to amino acid and glutathione metabolism. We propose tryptophan/kynurenine and S-adenosylmethionine as possible biomarkers for the previously established higher graft failure of DCD livers, and conclude that the associated pathways should be targeted in more exhaustive and quantitative investigations. PMID:27835640

  4. Mass Spectrometry Based Metabolomics Comparison of Liver Grafts from Donors after Circulatory Death (DCD) and Donors after Brain Death (DBD) Used in Human Orthotopic Liver Transplantation.

    PubMed

    Hrydziuszko, Olga; Perera, M Thamara P R; Laing, Richard; Kirwan, Jennifer; Silva, Michael A; Richards, Douglas A; Murphy, Nick; Mirza, Darius F; Viant, Mark R

    2016-01-01

    Use of marginal liver grafts, especially those from donors after circulatory death (DCD), has been considered as a solution to organ shortage. Inferior outcomes have been attributed to donor warm ischaemic damage in these DCD organs. Here we sought to profile the metabolic mechanisms underpinning donor warm ischaemia. Non-targeted Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry metabolomics was applied to biopsies of liver grafts from donors after brain death (DBD; n = 27) and DCD (n = 10), both during static cold storage (T1) as well as post-reperfusion (T2). Furthermore 6 biopsies from DBD donors prior to the organ donation (T0) were also profiled. Considering DBD and DCD together, significant metabolic differences were discovered between T1 and T2 (688 peaks) that were primarily related to amino acid metabolism, meanwhile T0 biopsies grouped together with T2, denoting the distinctively different metabolic activity of the perfused state. Major metabolic differences were discovered between DCD and DBD during cold-phase (T1) primarily related to glucose, tryptophan and kynurenine metabolism, and in the post-reperfusion phase (T2) related to amino acid and glutathione metabolism. We propose tryptophan/kynurenine and S-adenosylmethionine as possible biomarkers for the previously established higher graft failure of DCD livers, and conclude that the associated pathways should be targeted in more exhaustive and quantitative investigations.

  5. State of the Art of Mechanical Circulatory Support

    PubMed Central

    Mallidi, Hari R.; Anand, Jatin; Cohn, William E.

    2014-01-01

    Mechanical circulatory support of the failing heart has become an important means of treating end-stage heart disease. This rapidly growing therapeutic field has produced impressive clinical outcomes and has great potential to help thousands of otherwise terminal patients worldwide. In this review, we examine the state of the art of mechanical circulatory support: current practice, totally implantable systems of the future, evolving biventricular support mechanisms, the potential for myocardial recovery and adjunctive treatment methods, and miniaturized devices with expanded indications for therapy. PMID:24808767

  6. Overview of the 2011 Food and Drug Administration Circulatory System Devices Panel of the Medical Devices Advisory Committee Meeting on the CardioMEMS Champion Heart Failure Monitoring System.

    PubMed

    Loh, Joshua P; Barbash, Israel M; Waksman, Ron

    2013-04-16

    The CardioMEMS Champion Heart Failure Monitoring System (CardioMEMS, Atlanta, Georgia) is a permanently implantable pressure measurement system designed to wirelessly measure and monitor pulmonary artery (PA) pressure and heart rate in heart failure (HF) patients to guide ambulatory HF management and to reduce HF hospital stays. On December 8, 2011, the Food and Drug Administration (FDA) Circulatory System Device Panel reviewed the CardioMEMS Champion HF Monitoring System premarket approval (PMA) application. The majority of Panel members agreed that that the discussed monitoring system is safe for use in the indicated patient population. However, new information reported by the FDA with regard to preferential support in management of patients in the treatment group raised concerns among the Panel members with regard to potential bias in analyzing the efficacy of the device itself. Additionally, Panel members raised concerns with regard to the efficacy of the device in certain patient subpopulations. Hence, most Panel members decided that there was not reasonable assurance that the discussed monitoring system is effective. This summary aims to describe the discussions and recommendations made during this meeting.

  7. Human Systems Integration Requirements

    DTIC Science & Technology

    2009-09-01

    HUMAN SYSTEMS INTEGRATION OFFICE HUMAN SYSTEMS INTEGRATION REQUIREMENTS POCKET GUIDE SEPTEMBER 2009 Report Documentation Page Form ApprovedOMB No...collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE SEP 2009 2. REPORT TYPE Pocket Guide 3. DATES...COVERED 00-09-2009 to 00-12-2011 4. TITLE AND SUBTITLE Human Systems Integration Requirements Pocket Guide 5a. CONTRACT NUMBER 5b. GRANT NUMBER

  8. [Circulatory assist devices in cardiology].

    PubMed

    Ferrari, M; Figulla, H R

    2005-03-24

    One out of 13 patients with an acute myocardial infarction is endangered of cardiogenic shock. In addition, acute valvular leakage, shunt vitiae, and acute myocarditis can lead to acute myocardial failure. As a therapeutic option, mechanical assist devices offer cardiac support and hemodynamic stabilization under these circumstances. The following minimal-invasive devices are used in cardiology and intensive care medicine: intra-aortic balloon pulsation (IABP), intra-vascular axial screw pumps, extra-corporal centrifugal pumps with and without additional membrane oxygenator. The IABP improves left ventricular function by a systolic reduction of the after-load, and an increase of diastolic blood pressure dependent on myocardial function. In contrast, axial screw pumps and centrifugal pumps can provide circulatory support independently of myocardial function. Mechanical assist devices can prevent irreversible damage not only by offering a reduction of myocardial work load, but also by improving organ perfusion in cardiogenic shock situations. Another indication for mechanical circulatory support depicts high-risk coronary angioplasty if the left ventricular ejection fraction is severely reduced or the target vessel supplies more than 50 % of vital myocardium. In case of irreversible heart failure, turbine pumps or centrifugal pumps offer a stabilization for the patient's transfer to a cardiac surgery center. They can also be used for bridging to heart transplantation in acute situations. Technical improvements will enhance the use of mechanical assist devices in the near future. Especially the development of portable emergency devices will enrich therapeutic possibilities in cardiology and intensive care medicine.

  9. Magnetic resonance microscopy of flows and compressions of the circulatory, respiratory, and digestive systems in pupae of the tobacco hornworm, Manduca sexta.

    PubMed

    Hallock, Kevin J

    2008-01-01

    Circulatory, respiratory, and digestive motions in Manduca sexta pupae were observed using proton-density weighted and fast-imaging with steady-state free procession magnetic resonance microscopy. Proton-density weighted images clearly differentiated pupal air sacs from the hemolymph and organs because, as expected, the air sacs appeared dark in these images. Steady-state free procession imaging allowed real-time monitoring of respiration and circulation, creating movies of hemolymph circulation. Some of the movies show compression and inflation of the air sacs as well as abdominal movements consistent with previously reported ceolopulses. To our knowledge, this is the first magnetic resonance microscopy study of insect circulation and respiration and these preliminary results demonstrate the potential of magnetic resonance microscopy for studying in vivo dynamic processes in insects.

  10. [Importance of mechanical assist devices in acute circulatory arrest].

    PubMed

    Ferrari, Markus Wolfgang

    2016-03-01

    Mechanical assist devices are indicated for hemodynamic stabilization in acute circulatory arrest if conventional means of cardiopulmonary resuscitation are unable to re-establish adequate organ perfusion. Their temporary use facilitates further diagnostic and therapeutic options in selected patients, e.g. coronary angiography followed by revascularization.External thorax compression devices allow sufficient cardiac massage in case of preclinical or in-hospital circulatory arrest, especially under complex transfer conditions. These devices perform standardized thorax compressions at a rate of 80-100 per minute. Invasive mechanical support devices are used in the catheter laboratory or in the intensive care unit. Axial turbine pumps, e.g. the Impella, continuously pump blood from the left ventricle into the aortic root. The Impella can also provide right ventricle support by pumping blood from the vena cava into the pulmonary artery. So-called emergency systems or ECMO devices consist of a centrifugal pump and a membrane oxygenator allowing complete takeover of cardiac and pulmonary functions. Withdrawing blood from the right atrium and vena cava, oxygenated blood is returned to the abdominal aorta. Isolated centrifugal pumps provide left heart support without an oxygenator after transseptal insertion of a venous cannula into the left atrium.Mechanical assist devices are indicated for acute organ protection and hemodynamic stabilization for diagnostic and therapeutic measures as well as bridge to myocardial recovery. Future technical developments and better insights into the pathophysiology of mechanical circulatory support will broaden the spectrum of indications of such devices in acute circulatory arrest.

  11. Hemodynamics of Mechanical Circulatory Support.

    PubMed

    Burkhoff, Daniel; Sayer, Gabriel; Doshi, Darshan; Uriel, Nir

    2015-12-15

    An increasing number of devices can provide mechanical circulatory support (MCS) to patients with acute hemodynamic compromise and chronic end-stage heart failure. These devices work by different pumping mechanisms, have various flow capacities, are inserted by different techniques, and have different sites from which blood is withdrawn and returned to the body. These factors result in different primary hemodynamic effects and secondary responses of the body. However, these are not generally taken into account when choosing a device for a particular patient or while managing a patient undergoing MCS. In this review, we discuss fundamental principles of cardiac, vascular, and pump mechanics and illustrate how they provide a broad foundation for understanding the complex interactions between the heart, vasculature, and device, and how they may help guide future research to improve patient outcomes.

  12. Cell-Mediated Delivery of Nanoparticles: Taking Advantage of Circulatory Cells to Target Nanoparticles

    PubMed Central

    Anselmo, Aaron C.; Mitragotri, Samir

    2014-01-01

    Cellular hitchhiking leverages the use of circulatory cells to enhance the biological outcome of nanoparticle drug delivery systems, which often suffer from poor circulation time and limited targeting. Cellular hitchhiking utilizes the natural abilities of circulatory cells to: (i) navigate the vasculature while avoiding immune system clearance, (ii) remain relatively inert until needed and (iii) perform specific functions, including nutrient delivery to tissues, clearance of pathogens, and immune system surveillance. A variety of synthetic nanoparticles attempt to mimic these functional attributes of circulatory cells for drug delivery purposes. By combining the advantages of circulatory cells and synthetic nanoparticles, many advanced drug delivery systems have been developed that adopt the concept of cellular hitchhiking. Here, we review the development and specific applications of cellular hitchhiking-based drug delivery systems. PMID:24747161

  13. Cell-mediated delivery of nanoparticles: taking advantage of circulatory cells to target nanoparticles.

    PubMed

    Anselmo, Aaron C; Mitragotri, Samir

    2014-09-28

    Cellular hitchhiking leverages the use of circulatory cells to enhance the biological outcome of nanoparticle drug delivery systems, which often suffer from poor circulation time and limited targeting. Cellular hitchhiking utilizes the natural abilities of circulatory cells to: (i) navigate the vasculature while avoiding immune system clearance, (ii) remain relatively inert until needed and (iii) perform specific functions, including nutrient delivery to tissues, clearance of pathogens, and immune system surveillance. A variety of synthetic nanoparticles attempt to mimic these functional attributes of circulatory cells for drug delivery purposes. By combining the advantages of circulatory cells and synthetic nanoparticles, many advanced drug delivery systems have been developed that adopt the concept of cellular hitchhiking. Here, we review the development and specific applications of cellular hitchhiking-based drug delivery systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Hypoglycaemic bradycardia and circulatory collapse in a dog and a cat.

    PubMed

    Little, C J L

    2005-09-01

    Hypoglycaemia was accompanied by sinus bradycardia and circulatory collapse in a dog and a cat. In each case, when the hypoglycaemia was corrected by intravenous infusion of a glucose solution the bradycardia and circulatory failure were soon abolished, indicating that these abnormalities were caused by the hypoglycaemia. Similar observations have been made in human patients. To the author's knowledge, this is the first report documenting hypoglycaemic bradycardia in veterinary medicine.

  15. [Surgical correction of circulatory disturbance of the vertebral artery in trauma and degenerative diseases].

    PubMed

    Shchedrenok, V V; Zakhmatova, T V; Zuev, I V; Moguchaia, O V; Topol'skova, N V; Sebelev, K I; Malova, A M

    2014-01-01

    The article presents the results of examination and surgery of 185 patients with degenerative diseases as well as with a cervical spine trauma. The circulatory disturbance of the vertebral artery took place in all patients. A different degree of changes was observed in color duplex scanning. There were minor circulatory disturbances, course deformations (angular, C, S, V-shaped twists) and dissection of the vertebral artery. Color duplex scanning allowed estimating of local and system hemodynamic significance of extravasal influences. The strategy of treatment and volume of surgical interference were defined by the degree of circulatory disturbance in the vertebral artery.

  16. Human Systems Integration Introduction

    NASA Image and Video Library

    This lecture provides an overview of Human Systems Integration (HSI), its implementation cost and return on investment, HSI domains, how HSI fits into the NASA organization structure, HSI roles and...

  17. [Oral contraception and circulatory risks].

    PubMed

    Wingrave, S J

    1984-10-01

    The longterm prospective study of health effects of oral contraceptives (OCs) conducted by the Royal College of General Practitioners compared 23,000 OC users with 23,000 controls matched for age and marital status. As of 1981, 55 deaths attributable to circulatory problems had occurred in ever-users of OCs, ciompared to 10 in controls, giving a relative risk of 4.2 for OC users. No relation was found between duration of use and mortality risk among users, although mortality risks were greater at all durations of use than for nonusers. Parity was related to mortality risk among users but not among controls. The most significant factors affecting the relation between pill use and circulatory risk were age and smoking. Among users who smoked, the risk ratios were 3.4 for those aged 25-34, 4.2 for those aged 35-44, 7.4 for those aged 45 and over, and 5.1 for the entire group. Among nonsmoking pill users, the ratios were 1.6 for those aged 25-34, 3.3 for those aged 35-44, 4.6 for those 45 and over, and 3.2 for the total sample. Among smokers, the rates of excess deaths were 1 in 10,000 for users aged 15-34, 1 in 2000 for those aged 35-44, and 1 in550 for those aged 45 and over. Among nonsmokers, the rates were 1 in 50,000 users for those aged 25-34, 1 in 6700 for those aged 35-44, and 1 in 2500 for those aged 45 and over. The majority of deaths were attributed to ischemic cardiac problems and to sub-arachnoid hemorrhages, and risks appeared to be elevated in former as well as current users. The total incidence of circulatory effects in former users appears to be elevated only for cerebrovascular disorders, but the suggestion of residual effects requires further study before conclusions can be drawn. Smokers who developed cardiovascular or cerebrovascular problems were at 2-3 times greater risk of dying than were other women. The percentages of fatal cases of ischemic heart and cerebrovascular diseases were 22.8% among ever-users who smoked, 10.9% among controls who

  18. Subject-specific estimation of central aortic blood pressure via system identification: preliminary in-human experimental study.

    PubMed

    Fazeli, Nima; Kim, Chang-Sei; Rashedi, Mohammad; Chappell, Alyssa; Wang, Shaohua; MacArthur, Roderick; McMurtry, M Sean; Finegan, Barry; Hahn, Jin-Oh

    2014-10-01

    This paper demonstrates preliminary in-human validity of a novel subject-specific approach to estimation of central aortic blood pressure (CABP) from peripheral circulatory waveforms. In this "Individualized Transfer Function" (ITF) approach, CABP is estimated in two steps. First, the circulatory dynamics of the cardiovascular system are determined via model-based system identification, in which an arterial tree model is characterized based on the circulatory waveform signals measured at the body's extremity locations. Second, CABP waveform is estimated by de-convolving peripheral circulatory waveforms from the arterial tree model. The validity of the ITF approach was demonstrated using experimental data collected from 13 cardiac surgery patients. Compared with the invasive peripheral blood pressure (BP) measurements, the ITF approach yielded significant reduction in errors associated with the estimation of CABP, including 1.9-2.6 mmHg (34-42 %) reduction in BP waveform errors (p < 0.05) as well as 5.8-9.1 mmHg (67-76 %) and 6.0-9.7 mmHg (78-85 %) reductions in systolic and pulse pressure (SP and PP) errors (p < 0.05). It also showed modest but significant improvement over the generalized transfer function approach, including 0.1 mmHg (2.6 %) reduction in BP waveform errors as well as 0.7 (20 %) and 5.0 mmHg (75 %) reductions in SP and PP errors (p < 0.05).

  19. Human immune system variation

    PubMed Central

    Brodin, Petter; Davis, Mark M.

    2017-01-01

    The human immune system is highly variable between individuals but relatively stable over time within a given person. Recent conceptual and technological advances have enabled systems immunology analyses, which reveal the composition of immune cells and proteins in populations of healthy individuals. The range of variation and some specific influences that shape an individual’s immune system is now becoming clearer. Human immune systems vary as a consequence of heritable and non-heritable influences, but symbiotic and pathogenic microbes and other non-heritable influences explain most of this variation. Understanding when and how such influences shape the human immune system is key for defining metrics of immunological health and understanding the risk of immune-mediated and infectious diseases. PMID:27916977

  20. Spaceflight Human System Standards

    NASA Technical Reports Server (NTRS)

    Holubec, Keith; Tillman, Barry; Connolly, Jan

    2009-01-01

    NASA created a new approach for human system integration and human performance standards. NASA created two documents a standard and a reference handbook. The standard is titled NASA Space Flight Human-System Standard (SFHSS) and consists of two-volumes: Volume 1- Crew Health This volume covers standards needed to support astronaut health (medical care, nutrition, sleep, exercise, etc.) Volume 2 Human Factors, Habitability and Environmental Health This volume covers the standards for system design that will maintain astronaut performance (ie., environmental factors, design of facilities, layout of workstations, and lighting requirements). It includes classic human factors requirements. The new standards document is written in terms so that it is applicable to a broad range of present and future NASA systems. The document states that all new programs prepare system-specific requirements that will meet the general standards. For example, the new standard does not specify a design should accommodate specific percentiles of a defined population. Rather, NASA-STD-3001, Volume 2 states that all programs shall prepare program-specific requirements that define the user population and their size ranges. The design shall then accommodate the full size range of those users. The companion reference handbook, Human Integration Design Handbook (HIDH), was developed to capture the design consideration information from NASA-STD-3000, and adds spaceflight lessons learned, gaps in knowledge, example solutions, and suggests research to further mature specific disciplines. The HIDH serves two major purposes: HIDH is the reference document for writing human factors requirements for specific systems. HIDH contains design guidance information that helps insure that designers create systems which safely and effectively accommodate the capabilities and limitations of space flight crews.

  1. Spaceflight Human System Standards

    NASA Technical Reports Server (NTRS)

    Holubec, Keith; Tillman, Barry; Connolly, Jan

    2009-01-01

    NASA created a new approach for human system integration and human performance standards. NASA created two documents a standard and a reference handbook. The standard is titled NASA Space Flight Human-System Standard (SFHSS) and consists of two-volumes: Volume 1- Crew Health This volume covers standards needed to support astronaut health (medical care, nutrition, sleep, exercise, etc.) Volume 2 Human Factors, Habitability and Environmental Health This volume covers the standards for system design that will maintain astronaut performance (ie., environmental factors, design of facilities, layout of workstations, and lighting requirements). It includes classic human factors requirements. The new standards document is written in terms so that it is applicable to a broad range of present and future NASA systems. The document states that all new programs prepare system-specific requirements that will meet the general standards. For example, the new standard does not specify a design should accommodate specific percentiles of a defined population. Rather, NASA-STD-3001, Volume 2 states that all programs shall prepare program-specific requirements that define the user population and their size ranges. The design shall then accommodate the full size range of those users. The companion reference handbook, Human Integration Design Handbook (HIDH), was developed to capture the design consideration information from NASA-STD-3000, and adds spaceflight lessons learned, gaps in knowledge, example solutions, and suggests research to further mature specific disciplines. The HIDH serves two major purposes: HIDH is the reference document for writing human factors requirements for specific systems. HIDH contains design guidance information that helps insure that designers create systems which safely and effectively accommodate the capabilities and limitations of space flight crews.

  2. Acute circulatory deficiency due to endocrinal tumoral manipulation: the pinealoblastoma

    PubMed Central

    Heithem, Chemchihik; Issaoui, Ghazi; Khadraoui, Mejdi; Ladib, Mohamed; Naija, Walid; Said, Rachid

    2014-01-01

    We rapport the case of a patient presenting intra-abdominal metastasis of a pinealoblastoma, via a ventriculo-peritoneal shunt, confirmed by an anatomo-pathologic exam. The patient presented an acute hydrocephalus secondary to DVP dysfunction. The surgical manipulation of this metastasis had caused an acute circulatory deficiency due to massive serotonin release. In this case we analyze pineal gland physiology and serotonin effect on different systems. PMID:25422686

  3. Outline of the International Organization for Standardization Standard for Circulatory Support Devices (ISO 14708-5).

    PubMed

    Imachi, Kou; Mussivand, Tofy

    2010-09-01

    The rapid progress of artificial heart and circulatory support devices enables us to apply them to severe heart failure patients. Many types of circulatory support devices have been developed in the United States, Europe, and Japan. This situation urged the establishment of an International Organization for Standardization (ISO) Standard for the circulatory support devices. A new work, "Cardiac Ventricular Assist Devices," was proposed to the ISO/TC150/SC6 (TC150: Technical Committee of Implants for Surgery, SC6: Sub-committee of Active Implants) in 2000, and the work was finalized for publication at a 2009 meeting of the ISO/TC150 in Kyoto. In this article, the authors would like to introduce the ISO system and the outline of the ISO Standard for Circulatory Support Devices. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  4. Human Factors in Human-Systems Integration

    NASA Technical Reports Server (NTRS)

    Fitts, David J.; Sandor, Aniko; Litaker, Harry L., Jr.; Tillman, Barry

    2008-01-01

    Any large organization whose mission is to design and develop systems for humans, and train humans needs a well-developed integration and process plan to deal with the challenges that arise from managing multiple subsystems. Human capabilities, skills, and needs must be considered early in the design and development process, and must be continuously considered throughout the development lifecycle. This integration of human needs within system design is typically formalized through a Human-Systems Integration (HSI) program. By having an HSI program, an institution or organization can reduce lifecycle costs and increase the efficiency, usability, and quality of its products because human needs have been considered from the beginning.

  5. Post-exercise leg and forearm flexor muscle cooling in humans attenuates endurance and resistance training effects on muscle performance and on circulatory adaptation.

    PubMed

    Yamane, Motoi; Teruya, Hiroyasu; Nakano, Masataka; Ogai, Ryuji; Ohnishi, Norikazu; Kosaka, Mitsuo

    2006-03-01

    The influence of regular post-exercise cold application to exercised muscles trained by ergometer cycling (leg muscles) or handgrip exercise using a weight-loaded handgrip ergometer (forearm flexor muscles) was studied in human volunteers. Muscle loads were applied during exercise programs three to four times a week for 4-6 weeks. Besides measuring parameters characterizing muscle performance, femoral and brachial artery diameters were determined ultrasonographically. Training effects were identified by comparing pre- and post-training parameters in matched groups separately for the trained limbs cooled after exercise by cold-water immersion and the corresponding trained limbs kept at room temperature. Significant training effects were three times more frequent in the control than in the cold group, including increases in artery diameters in the control but not in the cold group. It is concluded that training-induced molecular and humoral adjustments, including muscle hyperthermia, are physiological, transient and essential for training effects (myofiber regeneration, muscle hypertrophy and improved blood supply). Cooling generally attenuates these temperature-dependent processes and, in particular, hyperthermia-induced HSP formation. This seems disadvantageous for training, in contrast to the beneficial combination of rest, ice, compression and elevation in the treatment of macroscopic musculo-tendinous damage.

  6. Temperature Management During Circulatory Arrest in Cardiac Surgery.

    PubMed

    Linardi, Daniele; Faggian, Giuseppe; Rungatscher, Alessio

    2016-03-01

    Surgery for complex aortic pathologies, such as acute dissections and aneurysms involving the aortic arch, remains one of the most technically and strategically challenging intervention in aortic surgery, requiring thorough understanding not only of cardiovascular physiology but also of neurophysiology (cerebral and spinal cord), and is still associated with significant mortality and morbidity. The introduction of deep hypothermia in the mid 1970s, allowing defined periods of circulatory arrest, has made possible the advent of modern aortic surgery requiring prolonged ischemic tolerance of central nervous system. In the late 1980s, when deep hypothermic circulatory arrest was the standard operative strategy for aortic surgery, selective cerebral perfusion, as an adjunct to deep hypothermia, made possible excellent neuroprotection and improved overall outcome. This encouraged the use of selective cerebral perfusion in combination with steadily increasing body core temperatures, a trend culminating in progressive promotion of moderate to mild hypothermia and even normothermia. The motivation for progressive temperature elevation was the limitation of adverse effects of deep hypothermia, in particular, reduction of systemic inflammatory response (and organ dysfunctions) and diminution of the risk of severe postoperative bleeding. However, adverse outcomes due to inappropriate temperature management (core temperatures too high for the required duration of circulatory arrest) are probably underreported. Indeed, complications historically associated with hypothermia are possibly overestimated.

  7. Effects of graded exercise-induced dehydration and rehydration on circulatory markers of oxidative stress across the resting and exercising human leg.

    PubMed

    Laitano, Orlando; Kalsi, Kameljit Kaur; Pearson, James; Lotlikar, Makra; Reischak-Oliveira, Alvaro; González-Alonso, José

    2012-05-01

    Exercise in the heat enhances oxidative stress markers in the human circulation, but the contribution of active skeletal muscle and the influence of hydration status remain unknown. To address this question, we measured leg exchange of glutathione (GSH), glutathione disulfide (GSSG), superoxide dismutase activity (SOD) and isoprostanes in seven males at rest and during submaximal one-legged knee extensor exercise in the following four conditions: (1) control euhydration (0% reduction in body mass), (2) mild-dehydration (2%), (3) moderate-dehydration (3.5%), (4) rehydration (0%). In all resting and control exercise conditions, a net GSH uptake was observed across the leg. In contrast, a significant leg release of GSH into the circulation (-354 ± 221 μmol/min, P < 0.05) was observed during exercise with moderate-dehydration, which was still present following full rehydration (-206 ± 122 μmol/min, P < 0.05). During exercise, mild and moderate-dehydration decreased both femoral venous erythrocyte SOD activity (195 ± 6 vs. 180 ± 5 U/L, P < 0.05) and plasma isoprostanes (30 ± 1.1 vs. 25.9 ± 1.3 pg/L, P < 0.05), but during rehydration these were not different from control. In conclusion, these findings suggest that active skeletal muscles release GSH into the circulation under moderate dehydration and subsequent rehydration, possibly to enhance the antioxidant defense.

  8. Circulatory changes of the novel adipokine adipolin/CTRP12 in response to metformin treatment and an oral glucose challenge in humans.

    PubMed

    Tan, Bee K; Chen, Jing; Hu, Jiamiao; Amar, Omar; Mattu, Harman S; Ramanjaneya, Manjunath; Patel, Vanlata; Lehnert, Hendrik; Randeva, Harpal S

    2014-12-01

    Adipolin/CTRP12 is a novel adipokine with anti-inflammatory and glucose-lowering properties in rodents. We sought to investigate the effects of metformin treatment (850 mg twice daily for 6 months) and a 2 h 75 g oral glucose tolerance test (OGTT) on serum adipolin concentrations in humans. Cross-sectional study [PCOS (n = 83) and control (n = 39) subjects]. Serum adipolin was measured by ELISA. Metformin treatment (850 mg twice daily for 6 months) was offered to all women with PCOS, 34 women participated but 21 women completed 6 months of metformin therapy. Reasons for subjects not completing the study were nausea and gastrointestinal side effects (n = 4), pregnancies (n = 5), noncompliance (n = 2) and loss of contact (n = 2). Metformin treatment (850 mg twice daily for 6 months) substantially increased serum adipolin concentrations (P < 0·05) in women with polycystic ovary syndrome (PCOS), a pro-inflammatory state associated with obesity, diabetes, dyslipidaemia and atherosclerosis. Furthermore, changes in waist-hip ratio, glucose, triglycerides, CRP and carotid intima media thickness showed significant negative associations with changes in adipolin levels (P < 0·05, P < 0·01); in multiple regression analyses, only changes in glucose were predictive of changes in adipolin levels (β = -0·570, P = 0·009). Serum adipolin decreased significantly in response to the OGTT in PCOS and control subjects at 90 min (P < 0·05) and 120 min (P < 0·01). Adipolin and/or novel pharmacologic agents that increase adipolin's circulating concentrations might constitute a novel approach in the treatment of insulin resistant states. © 2014 John Wiley & Sons Ltd.

  9. Human Balance System

    MedlinePlus

    ... and vision problems, and difficulty with concentration and memory. What is balance? Balance is the ability to maintain the body’s center of mass over its base of support. 1 A properly functioning balance system allows humans to see clearly while moving, identify orientation with ...

  10. Uncontrolled Donation After Circulatory Determination of Death.

    PubMed

    Ave, Anne L Dalle; Bernat, James L

    2016-01-01

    Uncontrolled donation after circulatory determination of death (uDCDD) refers to organ donation after a refractory cardiac arrest. We analyzed ethical issues raised by the uDCDD protocols of France, Madrid, and New York City. We recommend: (1) Termination of resuscitation (TOR) guidelines need refinement, particularly the minimal duration of resuscitation efforts before considering TOR; (2) Before enrolling in an uDCDD protocol, physicians must ascertain that additional resuscitation efforts would be ineffective; (3) Inclusion in an uDCDD protocol should not be made in the outpatient setting to avoid error and conflicts of interest; (4) The patient's condition should be reassessed at the hospital and reversible causes treated; (5) A no-touch period of at least 10 minutes should be respected to avoid the risk of autoresuscitation; (6) Once death has been determined, no procedure that may resume brain circulation should be used, including cardiopulmonary resuscitation, artificial ventilation, and extracorporeal membrane oxygenation; (7) Specific consent is required prior to entry into an uDCDD protocol; (8) Family members should be informed about the goals, risks, and benefits of planned uDCDD procedures; and (9) Public information on uDCDD is desirable because it promotes public trust and confidence in the organ donation system.

  11. Effect of Kampo formulations (traditional Chinese medicine) on circulatory parameters.

    PubMed

    Xu, F H; Uebaba, K

    1999-01-01

    The pharmacological action of 6 main Kampo formulations (1.Mao -to: [Japanese pictograph see text] MA HUANG TANG; 2. Shimbu -to: [Japanese pictograph see text]: ZHEN WU TANG; 3. Ninjin -to: [Japanese pictograph see text] : REN SHEN TANG; 4.Shigyaku-san: [Japanese pictograph see text] : SI NI SAN; 5.Keishi-to: Japanese pictograph see text] : GUI ZHI TANG; 6. Shimotsu - to: [Japanese pictograph see text] : SI WU TANG) on circulatory and autonomic nervous system were studied. 7 healthy adult males( age, 22.3 +/- 1.8 years old ) had 6 basic Kampo formulations, followed by noninvasive measurement of systolic blood pressure (SBP), mean blood pressure (MBP), diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO ), cardiacindex (CI), total peripheral resistance (TPR) by means of systolic area method of brachialsphygmography, every 30 minutes for 2 hours. As results, Mao - to induced an increase of BP,HR,SV,CO and CI, but a decrease of TPR. Keishi - to induced an increase of SBP and SV, and Shimotsu-to induced an increase of DBP and MBP, HR was slowed during former period after oral administration of Shigyaku - san, and later period after oral administration of Shimbu-to and Shimotsu-to. Regarding autonomic activity, Mao-to(former period of experiment ), Shimbu - to and Shimotsu-to induced supression of sympathetic activity, on the other hand, Mao-to (later period of experiment ) and Shiyaku - san showed a tendency of parasympathomimetic action. Mao -to induced the strongest activation of circulatory system of 6 main farmulations, and showed change of autonomic nervous activity, however, the change of circulatory and automonic nervous activity were not coincident each other. It was speculated that comprehensive mechanism of Mao-to were not only dependent of ephedrin, main active constituent of Mao, but also dependent on Keishi's vasodilatory action in it. Ninjin -to showed no actions on circulatory or autonomic system. This is indicated

  12. Bodily systems and the spatial-functional structure of the human body.

    PubMed

    Smith, Barry; Munn, Katherine; Papakin, Igor

    2004-01-01

    The human body is a system made of systems. The body is divided into bodily systems proper, such as the endocrine and circulatory systems, which are subdivided into many sub-systems at a variety of levels, whereby all systems and subsystems engage in massive causal interaction with each other and with their surrounding environments. Here we offer an explicit definition of bodily system and provide a framework for understanding their causal interactions. Medical sciences provide at best informal accounts of basic notions such as system, process, and function, and while such informality is acceptable in documentation created for human beings, it falls short of what is needed for computer representations. In our analysis we will accordingly provide the framework for a formal definition of bodily system and of associated notions.

  13. On a basic model of circulatory, fluid, and electrolyte regulation in the human system based upon the model of Guyton

    NASA Technical Reports Server (NTRS)

    White, R. J.

    1973-01-01

    A detailed description of Guyton's model and modifications are provided. Also included are descriptions of several typical experiments which the model can simulate to illustrate the model's general utility. A discussion of the problems associated with the interfacing of the model to other models such as respiratory and thermal regulation models which is prime importance since these stimuli are not present in the current model is also included. A user's guide for the operation of the model on the Xerox Sigma 3 computer is provided and two programs are described. A verification plan and procedure for performing experiments is also presented.

  14. Prime Time for Temporary Mechanical Circulatory Support.

    PubMed

    Eckman, Peter M; Hryniewicz, Katarzyna

    2015-07-01

    Cardiovascular care has witnessed a paradigm shift toward widespread use of mechanical circulatory support (MCS). In this context, the 2015 SCAI/ACC/HFSA/STS Clinical Expert Consensus Statement on the use of percutaneous mechanical circulatory support devices in cardiovascular care is a timely and welcome addition to the literature. This consensus statement is an important summary of the state of the field and a valuable method for all who participate in cardiovascular care to ensure up-to-date understanding of the treatment options available.

  15. Continuous cerebral hemodynamic measurement during deep hypothermic circulatory arrest

    PubMed Central

    Busch, David R.; Rusin, Craig G.; Miller-Hance, Wanda; Kibler, Kathy; Baker, Wesley B.; Heinle, Jeffrey S.; Fraser, Charles D.; Yodh, Arjun G.; Licht, Daniel J.; Brady, Kenneth M.

    2016-01-01

    While survival of children with complex congenital heart defects has improved in recent years, roughly half suffer neurological deficits suspected to be related to cerebral ischemia. Here we report the first demonstration of optical diffuse correlation spectroscopy (DCS) for continuous and non-invasive monitoring of cerebral microvascular blood flow during complex human neonatal or cardiac surgery. Comparison between DCS and Doppler ultrasound flow measurements during deep hypothermia, circulatory arrest, and rewarming were in good agreement. Looking forward, DCS instrumentation, alone and with NIRS, could provide access to flow and metabolic biomarkers needed by clinicians to adjust neuroprotective therapy during surgery. PMID:27699112

  16. Evaluation of the circulatory system in a population of seamen and deep-sea fishermen based on the analysis of blood circulation by means of Wezler and Boeger's method.

    PubMed

    Waśkiewicz, J

    1,397 seamen and deep-sea fishermen were examined, their polycardiographic records were evaluated. Their mean age was 44.1 +/- 9.3 years, while the period of the service at sea averaged 22.8 +/- 7.1 years. Using Wezler and Boeger's method, physical analysis of the blood circulation was carried out. Carotid arteriograms were evaluated with Donzelot's method. Electrocardiograms were evaluated following Minnesota Code 1982. In 587 people (42.0%) pathological changes in the blood circulation were revealed. In 260 people (18.6%) ECG records were abnormal. In 112 people (8%) border hypertension was recorded and in 486 people (13.3%) arterial hypertension was diagnosed. Abnormal speed of the central pulse wave, air chamber elasticity coefficient and peripheral resistance occurred in 35%, and abnormal carotid arteriograms were registered in 34.5% of the men examined. The data of the survey indicated that the risk of diseases of the circulatory system was high in the occupational group examined.

  17. Coagulation management in patients undergoing mechanical circulatory support.

    PubMed

    Görlinger, Klaus; Bergmann, Lars; Dirkmann, Daniel

    2012-06-01

    The incidence of bleeding and thrombo-embolic complications in patients undergoing mechanical circulatory support therapy remains high and is associated with bad outcomes and increased costs. The need for anticoagulation and anti-platelet therapy varies widely between different pulsatile and non-pulsatile ventricular-assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) systems. Therefore, a unique anticoagulation protocol cannot be recommended. Notably, most thrombo-embolic complications occur despite values of conventional coagulation tests being within the targeted range. This is due to the fact that conventional coagulation tests such as international normalised ratio (INR), activated partial thromboplastin time (aPTT) and platelet count cannot detect hyper- or hypofibrinolysis, hypercoagulability due to tissue factor expression on circulating cells or increased clot firmness, and platelet aggregation as well as response to anti-platelet drugs. By contrast, point-of-care (POC) whole blood viscoelastic tests (thromboelastometry/-graphy) and platelet function tests (impedance or turbidimetric aggregometry) reflect in detail the haemostatic status of patients undergoing mechanical circulatory support therapy and the efficacy of their anticoagulation and antiaggregation therapy. Therefore, monitoring of haemostasis using POC thromboelastometry/-graphy and platelet function analysis is recommended during mechanical circulatory support therapy to reduce the risk of bleeding and thrombo-embolic complications. Notably, these haemostatic tests should be performed repeatedly during mechanical circulatory support therapy since thrombin generation, clot firmness and platelet response may change significantly over time with a high inter- and intra-individual variability. Furthermore, coagulation management can be hampered in non-pulsatile VADs by acquired von Willebrand syndrome, and in general by acquired factor XIII deficiency as well as by heparin

  18. Human Exposure Database System (HEDS)

    EPA Pesticide Factsheets

    The Human Exposure Database System (HEDS) provides public access to data sets, documents, and metadata from EPA on human exposure. It is primarily intended for scientists involved in human exposure studies or work requiring such data.

  19. Effects of Simulated Pathophysiology on the Performance of a Decision Support Medical Monitoring System for Early Detection of Hemodynamic Decompensation in Humans

    DTIC Science & Technology

    2017-02-01

    AWARD NUMBER: W81XWH-13-2-0038 TITLE: Effects of Simulated Pathophysiology on the Performance of a Decision Support Medical Monitoring System for...Performance of a Decision Support Medical Monitoring System for Early Detection of Hemodynamic 5b. GRANT NUMBER Decompensation in Humans 5c. PROGRAM... circulatory response to stress, 3) blood loss and resuscitation with hypertonic saline, and 4) endotoxin administration to simulate the onset of sepsis

  20. Human portable preconcentrator system

    DOEpatents

    Linker, Kevin L.; Bouchier, Francis A.; Hannum, David W.; Rhykerd, Jr., Charles L.

    2003-01-01

    A preconcentrator system and apparatus suited to human portable use wherein sample potentially containing a target chemical substance is drawn into a chamber and through a pervious screen. The screen is adapted to capture target chemicals and then, upon heating, to release those chemicals into the chamber. Chemicals captured and then released in this fashion are then carried to a portable chemical detection device such as a portable ion mobility spectrometer. In the preferred embodiment, the means for drawing sample into the chamber comprises a reversible fan which, when operated in reverse direction, creates a backpressure that facilitates evolution of captured target chemicals into the chamber when the screen is heated.

  1. Integration and control of circulatory function.

    PubMed

    Guyton, A C; Cowley, A W; Young, D B; Coleman, T G; Hall, J E; DeClue, J W

    1976-01-01

    In this chapter we have emphasized especially the intrinsic controls of the circulation, such as the autoregulation mechanism for control of local blood flow, automatic control of cardiac output, long-term control of arterial pressure, long-term control of blood volume, and automatic distribution of fluids between the circulation and the interstitial spaces. The reasons for emphasizing these mechanisms are several: first, many experiments have now shown that the intrinsic mechanisms can provide highly stable long-term control of the circulation. Second, the value of the nervous and hormonal controls have probably been greatly overemphasized in the past. And, third, there are special complexities of the intrinsic controls--such as nonlinearities, delay in responses, and other effects--that have made these difficult to understand; it is probably these difficulties that have led to their underemphasis. However, we have not meant to take from the nervous and hormonal systems their true importance in circulatory control. For instance, intrinsic mechanisms have almost no capability for acute arterial pressure control (only for long-term control), and they have no mechanism for providing the drive necessary to make the animal ingest water and electrolytes. These require the nervous controls. Also, nervous reflexes are important in enhancing the effectiveness of blood volume control and control of cardiac pumping. Among the hormonal mechanisms, the renin-angiotensin system can provide a modest degree of arterial pressure control when the pressure falls below normal by eliciting a vasoconstrictor response in the peripheral blood vessels. However, this system seems to have an even more important renal function, a direct effect on kidneys to cause fluid retention; this in turn increases the body fluid volume and in this way increases the arterial pressure. Finally, the roles of ADH and aldosterone in the control of blood volume have probably been greatly overemphasized. On

  2. [The prevention of transfusion-associated circulatory overload].

    PubMed

    Ozier, Y

    2014-11-01

    Hydrostatic pulmonary edema is a frequent and severe complication of blood transfusion. Recent epidemiological studies open the way for a better prevention of Transfusion-Associated Circulatory Overload. Preventive measures rely solely on the medical and nursing staff. Mitigation strategies include a careful identification of patients and conditions at-risk, a single-unit transfusion policy in patients with chronic anemia, the use of slow infusion rates, the careful monitoring of patient vital signs (particularly systemic arterial blood pressure). Peritransfusion IV diuretics use is likely to be helpful, although optimal prescribing patterns have not been defined.

  3. Postcardiotomy mechanical circulatory support in two infants with williams' syndrome.

    PubMed

    Contrafouris, Constantinos A; Chatzis, Andrew C; Kanakis, Meletios A; Azariadis, Prodromos A; Mitropoulos, Fotios A

    2014-01-01

    Supravalvar aortic stenosis (SVAS) in patients with Williams' syndrome is often accompanied by coronary, pulmonary, and even myocardial lesions and therefore associated with increased perioperative morbidity and mortality. Extracorporeal membrane oxygenation (ECMO) provides reliable short-term mechanical circulatory support to patients, especially young, in acute postoperative cardiac failure when conventional means are ineffective. The incorporation of centrifugal pumps in these systems has made their use more efficient and less traumatic. We describe our experience of using the Levitronix CentriMag pump in two patients with Williams' syndrome who underwent surgical correction of supravalvular aortic stenosis.

  4. Postcardiotomy Mechanical Circulatory Support in Two Infants with Williams' Syndrome

    PubMed Central

    Contrafouris, Constantinos A.; Chatzis, Andrew C.; Kanakis, Meletios A.; Azariadis, Prodromos A.; Mitropoulos, Fotios A.

    2014-01-01

    Supravalvar aortic stenosis (SVAS) in patients with Williams' syndrome is often accompanied by coronary, pulmonary, and even myocardial lesions and therefore associated with increased perioperative morbidity and mortality. Extracorporeal membrane oxygenation (ECMO) provides reliable short-term mechanical circulatory support to patients, especially young, in acute postoperative cardiac failure when conventional means are ineffective. The incorporation of centrifugal pumps in these systems has made their use more efficient and less traumatic. We describe our experience of using the Levitronix CentriMag pump in two patients with Williams' syndrome who underwent surgical correction of supravalvular aortic stenosis. PMID:24741444

  5. Bleeding following deep hypothermia and circulatory arrest in children.

    PubMed

    Mossad, Emad B; Machado, Sandra; Apostolakis, John

    2007-03-01

    Deep hypothermic circulatory arrest (DHCA) is a technique of extracorporeal circulation commonly used in children with complex congenital heart defects undergoing surgical repairs. The use of profound cooling (20 degrees C) and complete cessation of circulation allow adequate exposure and correction of these complex lesions, with enhanced cerebral protection. However, the profound physiologic state of DHCA results in significant derangement of the coagulation system and a high incidence of postoperative bleeding. This review examines the impact of DHCA on bleeding and transfusion requirements in children and the pathophysiology of DHCA-induced platelet dysfunction. It also focuses on possible pharmacologic interventions to decrease bleeding following DHCA in children.

  6. Changes of circulatory and nervous diseases mortality patterns during periods of exceptional solar events

    NASA Astrophysics Data System (ADS)

    Podolska, Katerina

    2017-04-01

    The paper contains a statistical analysis of exceptional solar events and daily numbers of deaths from diseases from ICD-10 group VI. Diseases of the nervous system, group IX. Diseases of the circulatory system, and overall daily numbers of deaths in the Czech Republic. It is demonstrated that neurological diseases exhibit greater instability during the period of rising and falling solar activity. Specifically, we study the daily number of deaths separately for both sexes at the age groups under 39 and 40+ during the Solar Cycles No. 23 and No. 24. We focus mainly on exceptional solar events such as a "Bastille Day event" on July 14, 2000 (class X5), "Halloween solar storm" on October 28, 2003 (class X17), and events on January 7, 1997, April 2, 2000 (class X20), or September 7, 2005 (class X15). Special attention is given to "St. Patrick's Day storm" on March 17, 2015, the strongest geomagnetic storm of the Solar Cycle No. 24 that occurred following a coronal mass ejection (CME). We investigate changes in daily numbers of deaths during 1 month before and 1 month after these exceptional solar events. We take specific storm dynamics of geophysical parameters into consideration, and we also apply the results of risky characteristics of expositions by ionospheric and geomagnetic parameters. It is verified that, for diseases of the nervous system, women are generally more sensitive than men. On the contrary, this differences between men and women are not found for diseases of the circulatory system. Our findings suggest that the impact of hazardous space weather conditions on human health depends on the specific course and strength of individual solar storm.

  7. Biplane roentgen videometric system for dynamic, 60/sec, studies of the shape and size of circulatory structures, particularly the left ventricle.

    NASA Technical Reports Server (NTRS)

    Ritman, E. L.; Sturm, R. E.; Wood, E. H.

    1973-01-01

    An operator interactive video system for the measurement of roentgen angiographically outlined structures is described. Left ventricular volume and three-dimensional shapes are calculated from up to 200 pairs of diameters measured from ventriculograms at the rate of 60 pairs of biplane images per second. The accuracy and reproducibility of volumes calculated by the system were established by analysis of roentgenograms of inanimate objects of known volume and by comparison of left ventricular stroke volumes calculated by the system with the stroke volumes calculated by an indicator-dilution technique and an aortic root electromagnetic flowmeter. Computer-generated display of the large amounts of data obtained by the videometry system is described.

  8. [Peroxisome proliferator-activated receptors (PPAR) in pathophysiology of the circulatory system and prospective use of agonists of these receptors in therapy].

    PubMed

    Bełtowski, Jerzy; Wójcicka, Grazyna; Jamroz, Anna

    2003-01-01

    Peroxisome proliferator-activated receptors (PPARs) are ligand-activated nuclear receptors which regulate the expression of target genes. Three types of PPAR have been identified: PPAR alpha, PPAR beta/delta and PPAR gamma. The known endogenous PPAR ligands are polyunsaturated fatty acids and eicosanoids, such as 15-deoxy-delta 12,14-prostaglandin J2 and leukotriene B4. Two classes of drugs, fibrates and thiazolidinediones, bind to PPAR alpha and PPAR gamma, respectively. PPARs are involved in the regulation of the lipid metabolism and adipogenesis but are also expressed in the vasculature. PPARs activators inhibit inflammatory reactions within the vascular wall, inhibit vascular smooth muscle cells migration and proliferation and affect foam cells formation by changing the expression of scavenger receptors. PPAR agonists lower blood pressure and improve endothelial function in different animal models of hypertension as well as in humans. PPAR gamma ligands inhibit the development of atherosclerosis in LDL receptor deficient and apolipoprotein E deficient mice and in diabetic humans. PPAR gamma agonists have also been shown to attenuate myocardial hypertrophy and protect against ischemia-reperfuion injury.

  9. Human portable preconcentrator system

    DOEpatents

    Linker, Kevin L.; Brusseau, Charles A.; Hannum, David W.; Puissant, James G.; Varley, Nathan R.

    2003-08-12

    A preconcentrator system and apparatus suited to human portable use wherein sample potentially containing a target chemical substance is drawn into a chamber and through a pervious screen. The screen is adapted to capture target chemicals and then, upon heating, to release those chemicals into the chamber. Chemicals captured and then released in this fashion are then carried to a portable chemical detection device such as a portable ion mobility spectrometer. In the preferred embodiment, the means for drawing sample into the chamber comprises a reversible fan which, when operated in reverse direction, creates a backpressure that facilitates evolution of captured target chemicals into the chamber when the screen is heated. The screen can be positioned directly in front of the detector prior to heating to improve detection capability.

  10. Splanchnic vasodilation and hyperdynamic circulatory syndrome in cirrhosis

    PubMed Central

    Bolognesi, Massimo; Di Pascoli, Marco; Verardo, Alberto; Gatta, Angelo

    2014-01-01

    Portal hypertension is a clinical syndrome which leads to several clinical complications, such as the formation and rupture of esophageal and/or gastric varices, ascites, hepatic encephalopathy and hepato-renal syndrome. In cirrhosis, the primary cause of the increase in portal pressure is the enhanced resistance to portal outflow. However, also an increase in splanchnic blood flow worsens and maintains portal hypertension. The vasodilatation of arterial splanchnic vessels and the opening of collateral circulation are the determinants of the increased splanchnic blood flow. Several vasoactive systems/substances, such as nitric oxide, cyclooxygenase-derivatives, carbon monoxide and endogenous cannabinoids are activated in portal hypertension and are responsible for the marked splanchnic vasodilatation. Moreover, an impaired reactivity to vasoconstrictor systems, such as the sympathetic nervous system, vasopressin, angiotensin II and endothelin-1, plays a role in this process. The opening of collateral circulation occurs through the reperfusion and dilatation of preexisting vessels, but also through the generation of new vessels. Splanchnic vasodilatation leads to the onset of the hyperdynamic circulatory syndrome, a syndrome which occurs in patients with portal hypertension and is characterized by increased cardiac output and heart rate, and decreased systemic vascular resistance with low arterial blood pressure. Understanding the pathophysiology of splanchnic vasodilatation and hyperdynamic circulatory syndrome is mandatory for the prevention and treatment of portal hypertension and its severe complications. PMID:24627591

  11. Splanchnic vasodilation and hyperdynamic circulatory syndrome in cirrhosis.

    PubMed

    Bolognesi, Massimo; Di Pascoli, Marco; Verardo, Alberto; Gatta, Angelo

    2014-03-14

    Portal hypertension is a clinical syndrome which leads to several clinical complications, such as the formation and rupture of esophageal and/or gastric varices, ascites, hepatic encephalopathy and hepato-renal syndrome. In cirrhosis, the primary cause of the increase in portal pressure is the enhanced resistance to portal outflow. However, also an increase in splanchnic blood flow worsens and maintains portal hypertension. The vasodilatation of arterial splanchnic vessels and the opening of collateral circulation are the determinants of the increased splanchnic blood flow. Several vasoactive systems/substances, such as nitric oxide, cyclooxygenase-derivatives, carbon monoxide and endogenous cannabinoids are activated in portal hypertension and are responsible for the marked splanchnic vasodilatation. Moreover, an impaired reactivity to vasoconstrictor systems, such as the sympathetic nervous system, vasopressin, angiotensin II and endothelin-1, plays a role in this process. The opening of collateral circulation occurs through the reperfusion and dilatation of preexisting vessels, but also through the generation of new vessels. Splanchnic vasodilatation leads to the onset of the hyperdynamic circulatory syndrome, a syndrome which occurs in patients with portal hypertension and is characterized by increased cardiac output and heart rate, and decreased systemic vascular resistance with low arterial blood pressure. Understanding the pathophysiology of splanchnic vasodilatation and hyperdynamic circulatory syndrome is mandatory for the prevention and treatment of portal hypertension and its severe complications.

  12. [Evaluation of changes in the central and peripheral circulatory system under the influence of physical training carried out under the standard procedure of improving patients after acute coronary syndrome].

    PubMed

    Kapusta, Joanna; Kapusta, Anna; Kowalski, Jan; Irzmański, Robert

    2016-06-01

    The observed with age, atherosclerotic changes in vessels and increasing damage to the vascular endothelium, causing an increase in the occurrence of cardiovascular events. An important element in the rehabilitation of patients with coronary artery disease is a physical activity, to complement the pharmacological treatment. The aim of the study was to evaluate the influence of a controlled exercise training on changes in central and peripheral circulatory system in patients after acute coronary syndrome. Group comprising 92 patients were divided into three subgroups. The rehabilitation period ranged from 2 to 4 weeks. In group I and II performed a series of interval training on a bicycle ergometer supplemented by general conditioning exercises; in the group III training individually tailored program, consisting of breathing exercises, relaxation and small muscle groups. In all groups, before and after the training cycle test was performed impedance plethysmography of the chest, echocardiography, exercise test. After completing the program, the parameters plethysmography improved in all groups, with the largest changes were observed in the group treated to the longest training: increase PAmpl (pulse wave amplitude) of 16.7% and PSlope (systolic slope) of 17.6%, while decline in the value of CT (crest time) by 5.7% and PT (propagation time) by 6.3%. In groups, which carried out a controlled exercise training have improved as well: exercise capacity of patients, stroke volume SV, cardiac output CO and global myocardial contractility EF. Moreover, a correlation between the results plethysmography parameters and SV, CO and EF. Controlled physical training, which comes under the standard procedure rehabilitation of patients after acute coronary syndrome, leads to better blood perfusion in vessels of the legs and improve myocardial functional parameters, thereby affecting the growth of physical capacity of patients. © 2016 MEDPRESS.

  13. Quantitative three-dimensional dynamic imaging of structure and function of the cardiopulmonary and circulatory systems in all regions of the body

    NASA Technical Reports Server (NTRS)

    Sturm, R. E.; Ritman, E. L.; Wood, E. H.

    1975-01-01

    The background for, and design of a third generation, general purpose, all electronic spatial scanning system, the DSR is described. Its specified performance capabilities provide dynamic and stop action three dimensional spatial reconstructions of any portion of the body based on a minimum exposure time of 0.01 second for each 28 multiplanar 180 deg scanning set, a maximum scan repetition rate of sixty 28 multiplane scan sets per second, each scan set consisting of a maximum of 240 parallel cross sections of a minimum thickness of 0.9 mm, and encompassing a maximum cylindrical volume about 23 cm in length and up to 38 cm in diameter.

  14. Quantitative three-dimensional dynamic imaging of structure and function of the cardiopulmonary and circulatory systems in all regions of the body

    NASA Technical Reports Server (NTRS)

    Sturm, R. E.; Ritman, E. L.; Wood, E. H.

    1975-01-01

    The background for, and design of a third generation, general purpose, all electronic spatial scanning system, the DSR is described. Its specified performance capabilities provide dynamic and stop action three dimensional spatial reconstructions of any portion of the body based on a minimum exposure time of 0.01 second for each 28 multiplanar 180 deg scanning set, a maximum scan repetition rate of sixty 28 multiplane scan sets per second, each scan set consisting of a maximum of 240 parallel cross sections of a minimum thickness of 0.9 mm, and encompassing a maximum cylindrical volume about 23 cm in length and up to 38 cm in diameter.

  15. Feasibility of a TinyPump system for pediatric CPB, ECMO, and circulatory assistance: hydrodynamic performances of the modified pump housing for implantable TinyPump.

    PubMed

    Yokoyama, Naoyuki; Suzuki, Masaaki; Hoshi, Hideo; Ohuchi, Katsuhiro; Fujimoto, Tetsuo; Takatani, Setsuo

    2007-01-01

    The TinyPump is a miniature centrifugal blood pump with an extremely small priming volume of 5 ml, allowing blood transfusion free cardiopulmonary bypass as well as extracorporeal membrane oxygenation in pediatric patients. In this study, a new pump housing with the angled inlet port (25 degrees toward impeller center with respect to the flow axis) was designed to optimize the pump displaced volume and to extend the application of the TinyPump to implantable support The fluid dynamic performance analysis revealed that the head pressure losses increased from 3 to 17 mm Hg in comparison with straight port design as the pump rotational speed increased from 2,000 to 4,000 rpm. This was probably caused by perturbed flow patterns at the site of the inlet bent port area and streamline hitting the off-center of the impeller. No significant effect on pumping efficiency was observed because of modification in inlet port design. Modification in the inflow and outflow port designs together with the drive mechanism reduces the height of the pump system, including the motor, to 27 mm yielding the displaced volume of 68 ml in comparison with 40 mm of the paracorporeal system with the displaced volume of 105 ml. Further analysis in terms of hemolytic as well as antithrombogenic performance will be carried out to finalize the housing design for the implantable version of the TinyPump.

  16. Human Systems Roadmap Review

    DTIC Science & Technology

    2016-02-09

    Performance Human Aspects of Operations in Military Environments Dr. Ray Perez (Navy) Dr. Todd Nelson (AF) Dr. Mike LaFiandra (Army) Dr. Liz Bowman...Interfaces and Cognitive Processes Human Aspects of Operations in Military Environments Protection, Sustainment, and Warfighter Performance Right Person...mission command and tactical intelligence human - agent teaming  Personalized, integrated assessments and training to improve performance

  17. Normal behaviour of circulatory parameters during exercise. Reference values for heart rate and systemic blood pressure. The ECCIS Project data. Epidemiologia e Clinica della Cardiopatia Ischemica Silente.

    PubMed

    Menghini, F; Dally, L; Fazzini, P F; Menotti, A; Prati, P L; Rovelli, F; Antoniucci, D; Seccareccia, F

    1995-08-01

    The study of simultaneous variations in heart rate (HR) and systemic blood pressure is of great interest in ergometric practice complementing the analysis of the ST segment by ECG. This paper examines data proceeding from 500 consecutive, normal, exercise stress tests with the aim of offering reference values on the step-by-step behaviour of HR, systolic and diastolic blood pressure (SBP, DBP) during exercise in a normal population. The sample comes from a large epidemiological study (ECCIS Project) conducted on 4842 healthy, working men, aged 40-59, which proposes to identify, by a 3 stage procedure, subjects with totally asymptomatic coronary artery disease (type I silent ischemia). A further aim of our paper is to examine the influence of some physiological variables (age, height, weight, body mass index, resting HR, SBP and DBP) on the response to effort of HR, SBP and DBP; reciprocal HR/SBP adjustment during exercise; maximal attained workload and recovery time. Due to a preliminary observation that the rate of step-by-step increase in HR and SBP is inversely related to total duration, the population was split into 4 groups according to exercise tolerance (defined by maximal attained workload) to elaborate reference values. Furthermore our data demonstrate that: 1) SBP increases more rapidly with respect to HR for older and heavier subjects; 2) Exercise tolerance is inversely related to age, baseline HR and SBP, and directly related to weight and height; 3) return to baseline conditions, during recovery, is quicker for subjects with better exercise tolerance and lower baseline HR, SBP and weight.

  18. Management of the ACC/AHA Stage D patient: mechanical circulatory support.

    PubMed

    Baran, David A; Jaiswal, Abhishek

    2014-02-01

    From humble beginnings in 1963 with a single desperately ill patient, mechanical circulatory support has expanded exponentially to where it is a viable alternative for advanced heart failure patients. Some of these patients are awaiting transplant but others will have a mechanical heart pump as their ultimate treatment. The history of MCS devices is reviewed, along with the 4 trials that define the modern era of circulatory support. The practical aspects of life with an MCS device are reviewed and common problems encountered with MCS devices. Future trends including miniaturization and development of completely contained MCS systems are reviewed. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. The human vomeronasal system.

    PubMed

    Monti-Bloch, L; Jennings-White, C; Dolberg, D S; Berliner, D L

    1994-01-01

    We studied the functional characteristics of the vomeronasal system in clinically normal adult subjects of both sexes (ages 20-45). Chemosensory substances were administered in punctate pulses in a continuous air stream from the tip of a multifunctional miniprobe, which contained a nonpolarizable electrode. Negative potentials with the characteristics of receptor potentials were recorded from the surface of the vomeronasal organ (VNO) and olfactory epithelium (OE) in response to certain substances defined here as vomeropherins (see definition in the introduction of the main text) and to olfactants. Stimulation of the VNO with femtomole amounts of vomeropherins produced a local depolarization with the characteristics of a receptor potential. The same substances produced only a small response from the OE, and no response from the nasal respiratory mucosa. Three vomeropherins PH15, PH78, and PH84 were particularly well recognized by the VNO of most male subjects (p < .01; n = 30). Substances PH30, PH56, and PH94B, produced similar effects in the VNO of most female subjects (p < .01; n = 30). Responses to virtually all vomeropherins exhibited a sexual dimorphism. Stimulation of the OE with the same quantity of odorants 1,8-cineole and l-carvone produced depolarization of 6.8 +/- 2.6 mV, but little or no response in the VNO. Therefore, the human VNO seems to have a unique specificity for certain chemosensory substances when compared to the OE. Administration of PH15 and PH78 to the VNO of male subjects (but not to female subjects) significantly increased electrodermal activity (p < .02) and skin temperature (p < .01). On the other hand, administration of PH84 to the VNO of male subjects decreased skin temperature but had little effect on electrodermal activity. Autonomic changes were accompanied by an increased percentage of alpha-cortical activity for all three vomeropherins. In female subjects (but not in male subjects) vomeropherins PH56 and PH94B significantly

  20. Pediatric Donation After Circulatory Determination of Death: A Scoping Review.

    PubMed

    Weiss, Matthew J; Hornby, Laura; Witteman, William; Shemie, Sam D

    2016-03-01

    Although pediatric donation after circulatory determination of death is increasing in frequency, there are no national or international donation after circulatory determination of death guidelines specific to pediatrics. This scoping review was performed to map the pediatric donation after circulatory determination of death literature, identify pediatric donation after circulatory determination of death knowledge gaps, and inform the development of national or regional pediatric donation after circulatory determination of death guidelines. Terms related to pediatric donation after circulatory determination of death were searched in Embase and MEDLINE, as well as the non-MEDLINE sources in PubMed from 1980 to May 2014. Seven thousand five hundred ninety-seven references were discovered and 85 retained for analysis. All references addressing pediatric donation after circulatory determination of death were considered. Exclusion criteria were articles that did not address pediatric patients, animal or laboratory studies, surgical techniques, and local pediatric donation after circulatory determination of death protocols. Narrative reviews and opinion articles were the most frequently discovered reference (25/85) and the few discovered studies were observational or qualitative and almost exclusively retrospective. Retained references were divided into themes and analyzed using qualitative methodology. The main discovered themes were 1) studies estimating the number of potential pediatric donation after circulatory determination of death donors and their impact on donation; 2) ethical issues in pediatric donation after circulatory determination of death; 3) physiology of the dying process after withdrawal of life-sustaining therapy; 4) cardiac pediatric donation after circulatory determination of death; and 5) neonatal pediatric donation after circulatory determination of death. Donor estimates suggest that pediatric donation after circulatory determination of death will

  1. Human-System Technology

    DTIC Science & Technology

    2005-11-10

    Computing, this multidisciplinary field exploits advances in cognitive research together with those in computer science and related areas to optimize the...deep understanding of human cognition, perception, and/or locomotion; the relevant areas of computer science ; and the nature of the human activity to be

  2. Mechanical Circulatory Support: Heart Failure Therapy "in Motion".

    PubMed

    Ensminger, Stephan M; Gerosa, Gino; Gummert, Jan F; Falk, Volkmar

    Because the first generation of pulsatile-flow devices was primarily used to bridge the sickest patients to transplantation (bridge-to-transplant therapy), the current generation of continuous-flow ventricular assist devices qualifies for destination therapy for patients with advanced heart failure who are ineligible for transplantation. The first-generation devices were associated with frequent adverse events, limited mechanical durability, and patient discomfort due device size. In contrast, second-generation continuous-flow devices are smaller, more quiet, and durable, thus resulting in less complications and significantly improved survival rates. Heart transplantation remains an option for a limited number of patients only, and this fact has also triggered the discussion about the optimal timing for device implantation. The increasing use of continuous-flow devices has resulted in new challenges, such as adverse events during long-term support, and high hospital readmission rates. In addition, there are a number of device-related complications including mechanical problems such as device thrombosis, percutaneous driveline damage, as well as conditions such as hemolysis, infection, and cerebrovascular accidents. This review provides an overview of the evolution of mechanical circulatory support systems from bridge to transplantation to destination therapy including technological advances and clinical improvements in long-term patient survival and quality of life. In addition, recent changes in device implant strategies and current trials are reviewed and discussed. A brief glimpse into the future of mechanical circulatory support therapy will summarize the innovations that may soon enter clinical practice.

  3. Current discussions of DDREF, cataracts, circulatory diseases and dose limits.

    PubMed

    Müller, Wolfgang-Ulrich

    2015-04-01

    Although more than a century of radiation research has provided a lot of insight into radiation risk, there are still fields that need clarification. This is particularly true for the low dose range, meaning doses up to ∼100 mSv. One can detect biological effects in that dose range, but it is unclear whether these biological effects like mutations or chromosomal aberrations translate into health effects like cancer, cataracts or circulatory diseases. Thus, for radiation protection purposes, assumptions have to made that must be reappraised on the basis of new findings from time to time. Affected by new insights are currently the DDREF (dose and dose-rate effectiveness factor), cataracts and circulatory diseases. If the new findings are very convincing, dose limits have to be changed at short notice. If there are only weak indications, stability of the radiation protection system is more important than changing limits all the time. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Postauricular percutaneous power delivery for permanent mechanical circulatory support.

    PubMed

    Westaby, Stephen; Jarvik, Robert; Freeland, Andrew; Pigott, David; Robson, Desiree; Saito, Satoshi; Catarino, Pedro; Frazier, O H

    2002-05-01

    Percutaneous driveline infection continues to detract from both quality and length of life in patients with a left ventricular assist device. We have pursued an alternative route by using a skull-mounted percutaneous pedestal similar to cochlear implant technology. We have now used this method in patients implanted with the Jarvik 2000 heart (Jarvik Heart, Inc, New York, NY) as destination therapy for end-stage (New York Heart Association class IV) heart failure. Four men with cardiomyopathy aged 61 to 72 years received the Jarvik 2000 heart with postauricular power delivery for permanent mechanical circulatory support. The power cable was brought through the second posterior intercostal space and routed through the neck to a percutaneous titanium implant screwed to the skull. This joins with the cable to the external controller and battery. In 3 patients the pedestal healed well and remained free from infection up to 1 year. The system was user friendly, and the whole external apparatus is exchangeable. The second patient had a subdural hematoma. This caused us to improve the preparation and modify the implant procedure. For widespread use, permanent implantable circulatory support requires a reliable, user-friendly device with freedom from powerline infection. Our early experience with the Jarvik 2000 heart suggests that rigid fixation and the vascularity of scalp skin promote healing and reduce the risk of driveline infection.

  5. Mechanical circulatory assist for pulmonary embolism.

    PubMed

    Misawa, Y; Fuse, K; Yamaguchi, T; Saito, T; Konishi, H

    2000-11-01

    Optimal management of acute pulmonary embolism remains controversial, despite advances in thrombolytic therapy. Haemodynamic instability and, in particular, right ventricular dysfunction is associated with poor outcomes. Urgent surgical embolectomy has been the treatment of choice in this category of patients. We present two cases in which percutaneous cardiopulmonary support (PCPS) was used as an adjunct to thrombolytic therapy for progressive circulatory collapse secondary to massive acute pulmonary embolism. This experience suggests that PCPS may offer an attractive option for a condition which continues to carry significant morbidity and mortality.

  6. Disorder in Complex Human System

    NASA Astrophysics Data System (ADS)

    Akdeniz, K. Gediz

    2011-11-01

    Since the world of human and whose life becomes more and more complex every day because of the digital technology and under the storm of knowledge (media, internet, governmental and non-governmental organizations, etc...) the simulation is rapidly growing in the social systems and in human behaviors. The formation of the body and mutual interactions are left to digital technological, communication mechanisms and coding the techno genetics of the body. Deconstruction begins everywhere. The linear simulation mechanism with modern realities are replaced by the disorder simulation of human behaviors with awareness realities. In this paper I would like to introduce simulation theory of "Disorder Sensitive Human Behaviors". I recently proposed this theory to critique the role of disorder human behaviors in social systems. In this theory the principle of realty is the chaotic awareness of the complexity of human systems inside of principle of modern thinking in Baudrillard's simulation theory. Proper examples will be also considered to investigate the theory.

  7. Clinical examination for diagnosing circulatory shock.

    PubMed

    Hiemstra, Bart; Eck, Ruben J; Keus, Frederik; van der Horst, Iwan C C

    2017-08-01

    In the acute setting of circulatory shock, physicians largely depend on clinical examination and basic laboratory values. The daily use of clinical examination for diagnostic purposes contrasts sharp with the limited number of studies. We aim to provide an overview of the diagnostic accuracy of clinical examination in estimating circulatory shock reflected by an inadequate cardiac output (CO). Recent studies showed poor correlations between CO and mottling, capillary refill time or central-to-peripheral temperature gradients in univariable analyses. The accuracy of physicians to perform an educated guess of CO based on clinical examination lies around 50% and the accuracy for recognizing a low CO is similar. Studies that used predefined clinical profiles composed of several clinical examination signs show more reliable estimations of CO with accuracies ranging from 81 up to 100%. Single variables obtained by clinical examination should not be used when estimating CO. Physician's educated guesses of CO based on unstructured clinical examination are like the 'flip of a coin'. Structured clinical examination based on combined clinical signs shows the best accuracy. Future studies should focus on using a combination of signs in an unselected population, eventually to educate physicians in estimating CO by using predefined clinical profiles.

  8. Critical care ultrasonography in circulatory shock.

    PubMed

    Koster, Geert; van der Horst, Iwan C C

    2017-08-01

    The objective was to define the role of ultrasound in the diagnosis and the management of circulatory shock by critical appraisal of the literature. Assessment of any patient's hemodynamic profile based on clinical examination can be sufficient in several cases, but many times unclarities remain. Arterial catheters and central venous lines are commonly used in critically ill patients for practical reasons, and offer an opportunity for advanced hemodynamic monitoring. Critical care ultrasonography may add to the understanding of the hemodynamic profile at hand. Improvements in ultrasound techniques, for example, smaller devices and improved image quality, may reduce limitations and increase its value as a complementary tool. Critical care ultrasonography has great potential to guide decisions in the management of shock, but operators should be aware of limitations and pitfalls as well. Current evidence comes from cohort studies with heterogeneous design and outcomes. Use of ultrasonography for hemodynamic monitoring in critical care expands, probably because of absence of procedure-related adverse events. Easy applicability and the capacity of distinguishing different types of shock add to its increasing role, further supported by consensus statements promoting ultrasound as the preferred tool for diagnostics in circulatory shock.

  9. Clinical examination for diagnosing circulatory shock

    PubMed Central

    Hiemstra, Bart; Eck, Ruben J.; Keus, Frederik; van der Horst, Iwan C.C.

    2017-01-01

    Purpose of review In the acute setting of circulatory shock, physicians largely depend on clinical examination and basic laboratory values. The daily use of clinical examination for diagnostic purposes contrasts sharp with the limited number of studies. We aim to provide an overview of the diagnostic accuracy of clinical examination in estimating circulatory shock reflected by an inadequate cardiac output (CO). Recent findings Recent studies showed poor correlations between CO and mottling, capillary refill time or central-to-peripheral temperature gradients in univariable analyses. The accuracy of physicians to perform an educated guess of CO based on clinical examination lies around 50% and the accuracy for recognizing a low CO is similar. Studies that used predefined clinical profiles composed of several clinical examination signs show more reliable estimations of CO with accuracies ranging from 81 up to 100%. Summary Single variables obtained by clinical examination should not be used when estimating CO. Physician's educated guesses of CO based on unstructured clinical examination are like the ‘flip of a coin’. Structured clinical examination based on combined clinical signs shows the best accuracy. Future studies should focus on using a combination of signs in an unselected population, eventually to educate physicians in estimating CO by using predefined clinical profiles. PMID:28570301

  10. A contemporary review of mechanical circulatory support.

    PubMed

    Patel, Chetan B; Cowger, Jennifer A; Zuckermann, Andreas

    2014-07-01

    Mechanical circulatory support has seen numerous advances in the recent years, with important observations made to guide patient selection for the therapy, indications for use, and management of devices after implantation. There is rapid growth in the use of left ventricular assist device therapy (LVAD) for advanced heart failure, with a movement to pursue device intervention earlier in the disease spectrum before comorbidities escalate. With this increase in LVAD use have come new challenges, including unanticipated adverse events and high readmission rates. Simultaneously, complications encountered during LVAD support and an increased number of patients supported with a goal for transplant have had an important effect on the allocation of cardiac allografts. Still, the field continues to evolve and address these challenges in systematic fashion to provide novel solutions and meet the needs of a growing population with advanced heart failure. This has led to an extensive body of literature, ranging from case reports to multicenter clinical trials, which will enhance the future of LVAD technology and patient outcomes. This review summarizes important publications in mechanical circulatory support during the past 24 months.

  11. Human Error In Complex Systems

    NASA Technical Reports Server (NTRS)

    Morris, Nancy M.; Rouse, William B.

    1991-01-01

    Report presents results of research aimed at understanding causes of human error in such complex systems as aircraft, nuclear powerplants, and chemical processing plants. Research considered both slips (errors of action) and mistakes (errors of intention), and influence of workload on them. Results indicated that: humans respond to conditions in which errors expected by attempting to reduce incidence of errors; and adaptation to conditions potent influence on human behavior in discretionary situations.

  12. Intelligent systems for human resources.

    PubMed

    Kline, K B

    1988-11-01

    An intelligent system contains knowledge about some domain; it has sophisticated decision-making processes and the ability to explain its actions. The most important aspect of an intelligent system is its ability to effectively interact with humans to teach or assist complex information processing. Two intelligent systems are Intelligent Tutoring Systems (ITs) and Expert Systems. The ITSs provide instruction to a student similar to a human tutor. The ITSs capture individual performance and tutor deficiencies. These systems consist of an expert module, which contains the knowledge or material to be taught; the student module, which contains a representation of the knowledge the student knows and does not know about the domain; and the instructional or teaching module, which selects specific knowledge to teach, the instructional strategy, and provides assistance to the student to tutor deficiencies. Expert systems contain an expert's knowledge about some domain and perform specialized tasks or aid a novice in the performance of certain tasks. The most important part of an expert system is the knowledge base. This knowledge base contains all the specialized and technical knowledge an expert possesses. For an expert system to interact effectively with humans, it must have the ability to explain its actions. Use of intelligent systems can have a profound effect on human resources. The ITSs can provide better training by tutoring on an individual basis, and the expert systems can make better use of human resources through job aiding and performing complex tasks. With increasing training requirements and "doing more with less," intelligent systems can have a positive effect on human resources.

  13. Human Systems Modeling and Simulation

    DTIC Science & Technology

    2005-12-01

    individuals, organizations, and other social forms as systems of practices. A rereading of the propositional and system forms shows that they make no... social inter-dependencies that underwrite human behavior: designing, prototyping, testing and delivering extensions to Synergia’s ACCORD technology for...also and primarily the cognitive and social inter-dependencies that underwrite human behavior. • Develop technology for the computational specification

  14. Physiological characteristics of patients with schizophrenia prematurely dying from circulatory diseases.

    PubMed

    Chen, Pao-Huan; Tsai, Shang-Ying; Kuo, Chian-Jue; Chung, Kuo-Hsuan; Huang, Shou-Hung; Chen, Chiao-Chicy

    2016-09-01

    Patients with schizophrenia before reaching geriatric age are at high risk of circulatory mortality. However, investigations are lacking on the characteristics of physiological measurement among these at-risk patients. In this study, we followed acutely inpatients with schizophrenia disorder for cause of death through record linkage to the Death Certification System in Taiwan. Cases of patients who died because of circulatory morbidity (ICD-9 401-443) before turning 65 years old were used. Each schizophrenia case was then matched with two mentally healthy controls for the age and sex, and date of laboratory examination. Clinical data of all subjects were obtained by reviewing medical records. Totally, 81 patients with schizophrenia who died from circulatory diseases at mean ages of 48.0 ± 10.7 years were investigated. The mean age at the final acute psychiatric hospitalization was 43.0 ± 10.9 years. Multivariate analysis showed that elevated fasting serum glucose levels (95% confidence interval [CI] for odds ratio (OR) = 1.00-1.03), blood leukocyte counts (95% CI for odds ratio (OR) = 1.07-1.55), and heart rates on electrocardiogram (95% CI for OR = 1.04-1.10) in the final psychiatric hospitalization collectively provided the predictive validity for premature circulatory death. Systemic inflammatory activation and autonomic nervous system dysfunction along with dysregulation of glucose metabolism rather than lipids could be the physiological characteristics of schizophrenia patients at risk of premature circulatory mortality. © 2015 Wiley Publishing Asia Pty Ltd.

  15. [The importance of postoperative circulatory alterations in hepatic surgery].

    PubMed

    Koós, Olivér; Kovács, Tibor; Fülöp, András; Pekli, Damján; Ónody, Péter; Lukovich, Péter; Harsányi, László; Kupcsulik, Péter; Hahn, Oszkár; Szijártó, Attila

    2015-11-29

    There are two afferent (hepatic artery, portal vein) and one efferent (hepatic veins) systems responsible for the unique circulation of the liver. Given this special form of vasculature, acute, isolated (i.e. involving selectively one particular vessel) vascular occlusions may lead to different, however still life threatening conditions. Hence, it is essential to recognize these anomalies in order to preserve the healthy state of both the liver and the patient's lives. Acute circulatory failures are dominantly associated with liver surgery. Adequate therapy can only be provided promptly, if the clinician is well aware of the peculiarities of these conditions. The aim of this study is to overview the etiology and symptoms of these clinical conditions; furthermore to offer technical proposals for the required diagnostic and therapeutical steps via case reports. Furthermore, hepatic injury, caused by ischemia-reperfusion secondary to total vascular occlusion (Pringle maneuver) used in hepatic surgery is outlined.

  16. Donation after circulatory death: burying the dead donor rule.

    PubMed

    Rodríguez-Arias, David; Smith, Maxwell J; Lazar, Neil M

    2011-08-01

    Despite continuing controversies regarding the vital status of both brain-dead donors and individuals who undergo donation after circulatory death (DCD), respecting the dead donor rule (DDR) remains the standard moral framework for organ procurement. The DDR increases organ supply without jeopardizing trust in transplantation systems, reassuring society that donors will not experience harm during organ procurement. While the assumption that individuals cannot be harmed once they are dead is reasonable in the case of brain-dead protocols, we argue that the DDR is not an acceptable strategy to protect donors from harm in DCD protocols. We propose a threefold alternative to justify organ procurement practices: (1) ensuring that donors are sufficiently protected from harm; (2) ensuring that they are respected through informed consent; and (3) ensuring that society is fully informed of the inherently debatable nature of any criterion to declare death.

  17. Human Message Systems.

    ERIC Educational Resources Information Center

    Hopper, Robert

    A long-standing dispute over the best way to teach communication involves two major positions: teaching communication through practice/performance and teaching communication through theories and principles. This book describes both theories and practices, offering ideas within a systems framework so that each chapter introduces interacting…

  18. Circulatory estrogen level protects against breast cancer in obese women.

    PubMed

    Suba, Zsuzsanna

    2013-05-01

    Literary data suggest apparently ambiguous interaction between menopausal status and obesity-associated breast cancer risk based on the principle of the carcinogenic capacity of estrogen. Before menopause, breast cancer incidence is relatively low and adiposity is erroneously regarded as a protective factor against this tumor conferred by the obesity associated defective estrogen-synthesis. By contrast, in postmenopausal cases, obesity presents a strong risk factor for breast cancer being mistakenly attributed to the presumed excessive estrogen-production of their adipose-tissue mass. Obesity is associated with dysmetabolism and endangers the healthy equilibrium of sexual hormone-production and regular menstrual cycles in women, which are the prerequisites not only for reproductive capacity but also for somatic health. At the same time, literary data support that anovulatory infertility is a very strong risk for breast cancer in young women either with or without obesity. In the majority of premenopausal women, obesity associated insulin resistance is moderate and may be counteracted by their preserved circulatory estrogen level. Consequently, it is not obesity but rather the still sufficient estrogen-level, which may be protective against breast cancer in young adult females. In obese older women, never using hormone replacement therapy (HRT) the breast cancer risk is high, which is associated with their continuous estrogen loss and increasing insulin-resistance. By contrast, obese postmenopausal women using HRT, have a decreased risk for breast cancer as the protective effect of estrogen-substitution may counteract to their obesity associated systemic alterations. The revealed inverse correlation between circulatory estrogen-level and breast cancer risk in obese women should advance our understanding of breast cancer etiology and promotes primary prevention measures. New patents recommend various methods for the prevention and treatment of obesity

  19. Circulatory Estrogen Level Protects Against Breast Cancer in Obese Women

    PubMed Central

    Suba, Zsuzsanna

    2013-01-01

    Literary data suggest apparently ambiguous interaction between menopausal status and obesity-associated breast cancer risk based on the principle of the carcinogenic capacity of estrogen. Before menopause, breast cancer incidence is relatively low and adiposity is erroneously regarded as a protective factor against this tumor conferred by the obesity associated defective estrogen-synthesis. By contrast, in postmenopausal cases, obesity presents a strong risk factor for breast cancer being mistakenly attributed to the presumed excessive estrogen-production of their adipose-tissue mass. Obesity is associated with dysmetabolism and endangers the healthy equilibrium of sexual hormone-production and regular menstrual cycles in women, which are the prerequisites not only for reproductive capacity but also for somatic health. At the same time, literary data support that anovulatory infertility is a very strong risk for breast cancer in young women either with or without obesity. In the majority of premenopausal women, obesity associated insulin resistance is moderate and may be counteracted by their preserved circulatory estrogen level. Consequently, it is not obesity but rather the still sufficient estrogen-level, which may be protective against breast cancer in young adult females. In obese older women, never using hormone replacement therapy (HRT) the breast cancer risk is high, which is associated with their continuous estrogen loss and increasing insulin-resistance. By contrast, obese postmenopausal women using HRT, have a decreased risk for breast cancer as the protective effect of estrogen-substitution may counteract to their obesity associated systemic alterations. The revealed inverse correlation between circulatory estrogen-level and breast cancer risk in obese women should advance our understanding of breast cancer etiology and promotes primary prevention measures. New patents recommend various methods for the prevention and treatment of obesity

  20. Intraoperative care for aortic surgery using circulatory arrest

    PubMed Central

    Fernández Del Valle, David; González Alvarez, Adrián; Pérez-Lozano, Blanca

    2017-01-01

    The total circulatory arrest (CA) is necessary to achieve optimal surgical conditions in certain aortic pathologies, especially in those affecting the ascending aorta and aortic arch. During this procedure it is necessary to protect all the organs of ischemia, especially those of the central nervous system and for this purpose several strategies have been developed. The first and most important protective method is systemic hypothermia. The degree of hypothermia and the route of application have been evolving and currently tend to use moderate hypothermia (MH) (20.1–28 °C) associated with unilateral or bilateral selective cerebral perfusion methods. In this way the neurological results are better, the interval of security is greater and the times of extracorporeal circulation are smaller. Even so, it is necessary to take into account that there is the possibility of ischemia in the lower part of the body, especially of the abdominal viscera and the spinal cord, therefore the time of circulatory stop should be limited and not to exceed 80 minutes. Evidence of possible neurological drug protection is very weak and only mannitol, magnesium, and statins can produce some benefit. Inhalational anesthetics and some intravenous seem to have advantages, but more studies would be needed to test their long-term benefit. Other important parameters to be monitored during these procedures are blood glucose, anemia and coagulation disorders and acid-base balance. The recommended monitoring is common in complex cardiovascular procedures and it is of special importance the neurological monitoring that can be performed with several techniques, although currently the most used are Bispectral Index (BIS) and Near-Infrared Spectroscopy (NIRS). It is also essential to monitor the temperature routinely at the nasopharyngeal and bladder level and it is important to control coagulation with rotational thromboelastometry (ROTEM). PMID:28616347

  1. Umbilical arterial S-nitrosothiols in stressed newborns: role in perinatal circulatory transition.

    PubMed

    Gaston, B; Fry, E; Sears, S; Heroman, W M; Ignarro, L; Stamler, J S

    1998-12-30

    S-Nitrosothiols are potent endogenous vasodilators recently found to be in greater concentrations in fetal umbilical venous than arterial blood. We hypothesized that neonatal increases in SNOs may be involved in the normal human perinatal circulatory transition. Paired human umbilical artery and vein plasma samples were collected after birth. S-Nitrosothiol concentrations were measured as NO after photolysis--and NO3- after reduction in vanadium chloride--by chemiluminescence. Normal umbilical arterial serum SNO levels were nearly twice those of matched venous samples but were low in infants who did not transition normally to neonatal circulation. There was no difference in the concentration of NO3- between the normal and depressed infants. The parallel failure of some fetuses to switch both to a normal arteriovenous SNO relationship and a normal clinical post-partum state suggests that SNOs may be involved in the perinatal circulatory transition.

  2. Options for temporary mechanical circulatory support

    PubMed Central

    Saffarzadeh, Areo

    2015-01-01

    Temporary mechanical circulatory support (MCS) refers to a group of devices generally used for less than 30 days to maintain adequate organ perfusion by compensating for a failure of the pumping mechanism of the heart. The increased availability and rapid adoption of new temporary MCS strategies necessitate physicians to become familiar with devices placed both percutaneously and via median sternotomy. This review will examine the different options for commonly used temporary MCS devices including intra-aortic balloon pumps (IABPs), veno-arterial-extracorporeal membrane oxygenation (VA-ECMO), TandemHeart® (CardiacAssist, Pittsburg, PA, USA) Impella® and BVS 5000® (both Abiomed Inc., Danvers, MA, USA), CentriMag® and Thoratec percutaneous ventricular assist device (pVAD)® (both Thoratec Corporation, Pleasanton, CA, USA). A specific emphasis will be made to describe relevant mechanisms of action, standard placement strategies, hemodynamic effects, relevant contraindications and complications, and important daily management considerations. PMID:26793330

  3. Mechanical circulatory support in heart failure

    PubMed Central

    Szczurek, Wioletta; Suliga, Kamil; Rempega, Grzegorz; Rajwa, Paweł

    2016-01-01

    The increasing number of end-stage heart failure patients eligible for heart transplant and the disproportionately low number of donor hearts have led to increased interest in ventricular assist devices (VAD). These devices can be used as a bridge to decision, bridge to recovery, or bridge to candidacy. The main advantage of mechanical circulatory support (MCS) is the improvement of organ perfusion and function, which leads to better quality of life and survival. The MCS can also be used as a destination therapy in end-stage heart failure patients who are not eligible for heart transplant. It should be remembered that, despite the tangible benefits, VAD implantation may also be associated with the risk of serious complications, such as bleeding, infection, arrhythmias, blood clots, right ventricular failure, and cardiovascular events. This study presents an up-to-date overview of the current knowledge on the role of MCS in modern medicine. PMID:27516785

  4. Circulatory Failure During Noninhaled Forms of Cyanide Intoxication.

    PubMed

    Haouzi, Philippe; Tubbs, Nicole; Rannals, Matthew D; Judenherc-Haouzi, Annick; Cabell, Larry A; McDonough, Joe A; Sonobe, Takashi

    2017-03-01

    Our objective was to determine how circulatory failure develops following systemic administration of potassium cyanide (KCN). We used a noninhaled modality of intoxication, wherein the change in breathing pattern would not influence the diffusion of CN into the blood, akin to the effects of ingesting toxic levels of CN. In a group of 300 to 400 g rats, CN-induced coma (CN i.p., 7 mg/kg) produced a central apnea within 2 to 3 min along with a potent and prolonged gasping pattern leading to autoresuscitation in 38% of the animals. Motor deficits and neuronal necrosis were nevertheless observed in the surviving animals. To clarify the mechanisms leading to potential autoresuscitation versus asystole, 12 urethane-anesthetized rats were then exposed to the lowest possible levels of CN exposure that would lead to breathing depression within 7 to 8 min; this dose averaged 0.375 mg/kg/min i.v. At this level of intoxication, a cardiac depression developed several minutes only after the onset of the apnea, leading to cardiac asystole as PaO2 reached value approximately 15 Torr, unless breathing was maintained by mechanical ventilation or through spontaneous gasping. Higher levels of KCN exposure in 10 animals provoked a primary cardiac depression, which led to a rapid cardiac arrest by pulseless electrical activity (PEA) despite the maintenance of PaO2 by mechanical ventilation. These effects were totally unrelated to the potassium contained in KCN. It is concluded that circulatory failure can develop as a direct consequence of CN-induced apnea but in a narrow range of exposure. In this "low" range, maintaining pulmonary gas exchange after exposure, through mechanical ventilation (or spontaneous gasping), can reverse cardiac depression and restore spontaneous breathing. At higher level of intoxication, cardiac depression is to be treated as a specific and spontaneously irreversible consequence of CN exposure, leading to a PEA.

  5. The European Registry for Patients with Mechanical Circulatory Support (EUROMACS): first annual report.

    PubMed

    de By, Theo M M H; Mohacsi, Paul; Gummert, Jan; Bushnaq, Hasan; Krabatsch, Thomas; Gustafsson, Finn; Leprince, Pascal; Martinelli, Luigi; Meyns, Bart; Morshuis, Michiel; Netuka, Ivan; Potapov, Evgenij; Zittermann, Armin; Delmo Walter, Eva Maria; Hetzer, Roland

    2015-05-01

    The European Registry for Patients with Mechanical Circulatory Support (EUROMACS) was founded on 10 December 2009 with the initiative of Roland Hetzer (Deutsches Herzzentrum Berlin, Berlin, Germany) and Jan Gummert (Herz- und Diabeteszentrum Nordrhein-Westfalen, Bad Oeynhausen, Germany) with 15 other founding international members. It aims to promote scientific research to improve care of end-stage heart failure patients with ventricular assist device or a total artificial heart as long-term mechanical circulatory support. Likewise, the organization aims to provide and maintain a registry of device implantation data and long-term follow-up of patients with mechanical circulatory support. Hence, EUROMACS affiliated itself with Dendrite Clinical Systems Ltd to offer its members a software tool that allows input and analysis of patient clinical data on a daily basis. EUROMACS facilitates further scientific studies by offering research groups access to any available data wherein patients and centres are anonymized. Furthermore, EUROMACS aims to stimulate cooperation with clinical and research institutions and with peer associations involved to further its aims. EUROMACS is the only European-based Registry for Patients with Mechanical Circulatory Support with rapid increase in institutional and individual membership. Because of the expeditious data input, the European Association for Cardiothoracic Surgeons saw the need to optimize the data availability and the significance of the registry to improve care of patients with mechanical circulatory support and its potential contribution to scientific intents; hence, the beginning of their alliance in 2012. This first annual report is designed to provide an overview of EUROMACS' structure, its activities, a first data collection and an insight to its scientific contributions.

  6. The human fetal venous system: normal embryologic, anatomic, and physiologic characteristics and developmental abnormalities.

    PubMed

    Fasouliotis, Sozos J; Achiron, Reuven; Kivilevitch, Zvi; Yagel, Simcha

    2002-10-01

    The introduction of high-resolution ultrasonography combined with color-coded Doppler imaging offered a breakthrough in the evaluation of the human fetal venous system, considerably enhancing our understanding of fetal venous circulation in normal physiologic conditions, as well as providing us the ability to study circulatory changes in abnormal circumstances. The purpose of this study was to describe the normal anatomic development and complex of anomalies of the human fetal venous system and to review recently published series of these anomalies. Normal embryologic and anatomic development is described. An English language literature search of recent MEDLINE listings was performed to glean data from recently published series reporting prenatal diagnosis of the various anomalies and their associated malformations. Anomalies of the human fetal venous system occur sporadically, often associated with cardiac or other malformations. The pathophysiologic mechanisms leading to abnormal in utero development of the human venous system remain largely undetermined. On the basis of the type of vein involved, embryologic precursor, and etiologic correlation (primary or secondary), classification into 4 major groups is described. Prenatal evaluation of fetuses found to have anomalies of the venous system should include a careful search for cardiac anomalies, including pulmonary venous drainage, and a detailed anatomic survey of the umbilical, portal, hepatic, and ductal systems to determine aberrant communication and, if possible, to discover clues to systemic diseases or thromboembolic phenomena.

  7. Patient-specific modeling and multi-scale blood simulation for computational hemodynamic study on the human cerebrovascular system.

    PubMed

    Oshima, Marie; Torii, Ryo; Tokuda, Shigefumi; Yamada, Shigeki; Koizumi, Akio

    2012-09-01

    To develop a targeted drug delivery system for cerebrovascular disorders such as stroke, it is important to obtain detailed information on flow rates and hemodynamics of the human cerebrovascular system for individual patients. A patient-specific integrated numerical simulation system has been developed by the authors such that vascular geometry is constructed from medical images such as magnetic resonance imaging (MRI) or computed tomography (CT) data, and computational conditions are modeled mathematically to represent the realistic in vivo environments. In general, the three-dimensional numerical simulation using a patient-specific model is conducted only for a localized diseased region with atherosclerosis or an aneurysm. Although the analysis region is only a part of the circulatory system, the simulation should include the effects from the entire circulatory system. Since the peripheral network determines the flow distributions in the cerebrovascular system, the paper reviews the recent simulation methods to take into account the network by coupling the image-based three-dimensional simulation with a one- and zero-dimensional simulations as an outflow boundary condition The paper shows the mathematical modeling of the multi-scale outflow boundary condition and its applications to patient- specific models of the arterial circle of Willis. The results are compared to those using the conventional, free-stream boundary condition. As a result, the multi-scale outflow boundary condition shows a significant difference in flow rate of each artery and in flow distribution in the arterial circle of Willis.

  8. Heat produces uteroplacental circulatory disturbance in pregnant rats through action of corticotropin releasing hormone (CRH).

    PubMed

    Nakamura, H; Nagase, H; Ogino, K; Hatta, K; Matsuzaki, I

    2000-01-01

    There is some evidence showing an existence of corticotropin releasing hormone (CRH) and opioid peptides, including beta-endorphin (betaEP), in human placenta, whereas physiological roles of the placental peptides in response to stress remain to be elucidated. To clarify the involvement of CRH and opioid system in the uteroplacental circulation in the pregnant rats exposed to heat, we examined the effects of heat and intravenous administration of CRH receptor antagonist alpha-helical CRH (9-41) on the uteroplacental blood flow, as well as blood CRH, and blood and placental betaEP in pregnant rats. Heat did not change uterine blood flow in virgin rats, but reduced uteroplacental blood flow in pregnant rats. The reduced uteroplacental blood flow induced by heat in pregnant rats was reversed by the administration of alpha-helical CRH. Independent of the status of pregnancy, heat increased blood CRH, which was not reversed by alpha-helical CRH. Although heat did not change placental betaEP, alpha-helical CRH reduced blood and placenta betaEP in pregnant rats. These results suggest that the uteroplacental circulatory disturbance caused by heat is mediated by CRH, possibly through the involvement of CRH receptor in rat placenta. The placental opioid system seems unlikely to be involved in the mediation of uteroplacental circulation.

  9. NASA Space Flight Human System Standards

    NASA Technical Reports Server (NTRS)

    Tillman, Barry; Pickett, Lynn; Russo, Dane; Stroud, Ken; Connolly, Jan; Foley, Tico

    2007-01-01

    NASA has begun a new approach to human factors design standards. For years NASA-STD-3000, Manned Systems Integration Standards, has been a source of human factors design guidance for space systems. In order to better meet the needs of the system developers, NASA is revising its human factors standards system. NASA-STD-3000 will be replaced by two documents: set of broad human systems specifications (including both human factors and medical topics) and a human factors design handbook

  10. Circulatory response and autonomic nervous activity during gum chewing.

    PubMed

    Hasegawa, Yoko; Sakagami, Joe; Ono, Takahiro; Hori, Kazuhiro; Zhang, Min; Maeda, Yoshinobu

    2009-08-01

    Mastication has been proven to enhance the systemic circulation, with circulatory responses seeming to be largely regulated by autonomic nervous activity via a more complex regulatory system than those of other activities. However, few studies have examined the relationships between changes in autonomic nervous activity and the systemic circulation that are induced by masticatory movement. We investigated changes in the systemic circulation and autonomic nervous activity during gum chewing to clarify the influence of mastication. Electrocardiograms, arterial blood pressure, and masseter electromyograms were taken while chewing gum continuously as indicators of systemic circulation in 10 healthy subjects with normal dentition. Cardiac sympathetic activity and vagus nervous activity, as well as vasomotor sympathetic nervous activity, were evaluated by fluctuation analysis of heart rate and blood pressure. Repeated analysis of variance and multiple comparisons were performed to determine chronological changes in each indicator during gum chewing. Gum chewing increased the heart rate and the mean arterial pressure. Although cardiac sympathetic activity and vagus nervous activity showed significant changes, vasomotor sympathetic nervous activity did not. These results suggest that changes in the autonomic nervous activity of the heart are mainly involved in the enhancement of systemic circulation with gum chewing. This explains some characteristics of autonomic nervous regulation in masticatory movement.

  11. Human System Integration: Regulatory Analysis

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This document was intended as an input to the Access 5 Policy Integrated Product team. Using a Human System Integration (HIS) perspective, a regulatory analyses of the FARS (specifically Part 91), the Airman s Information Manual (AIM) and the FAA Controllers Handbook (7110.65) was conducted as part of a front-end approach needed to derive HSI requirements for Unmanned Aircraft Systems (UAS) operations in the National Airspace System above FL430. The review of the above aviation reference materials yielded eighty-four functions determined to be necessary or highly desirable for flight within the Air Traffic Management System. They include categories for Flight, Communications, Navigation, Surveillance, and Hazard Avoidance.

  12. Opioid system and human emotions.

    PubMed

    Nummenmaa, Lauri; Tuominen, Lauri

    2017-04-10

    Emotions are states of vigilant readiness that guide human and animal behaviour during survival-salient situations. Categorical models of emotions posit neurally and physiologically distinct human basic emotions (anger, fear, disgust, happiness, sadness, and surprise) that govern different survival functions. Opioid receptors are expressed abundantly in the mammalian emotion circuit and the opioid system modulates a multitude of functions related to arousal and motivation. Yet, its specific contribution to different basic emotions has remained poorly understood. Here we review how the endogenous opioid system and particularly the μ receptor contributes to emotional processing in humans. Endogenous opioid system activation is consistently associated with both pleasant and unpleasant emotions. In general, exogenous opioid agonists promote approach-oriented emotions (anger, pleasure) and inhibit avoidance-oriented emotions (fear, sadness). Opioids also modulate social bonding and affiliative behaviour, and prolonged opioid abuse may render both social bonding and emotion recognition circuits dysfunctional. For surprise and disgust, no clear evidence of opioidergic modulation was found. Taken together, the opioid systems contribute to a wide array of positive and negative emotions via their general role in modulating the approach versus avoidance motivation associated with specific emotions. Because of the protective effects of opioid-system-mediated prosociality and positive mood, the opioid system may constitute an important factor contributing to psychological and psychosomatic resiliency.

  13. Human Factors Considerations in System Design

    NASA Technical Reports Server (NTRS)

    Mitchell, C. M. (Editor); Vanbalen, P. M. (Editor); Moe, K. L. (Editor)

    1983-01-01

    Human factors considerations in systems design was examined. Human factors in automated command and control, in the efficiency of the human computer interface and system effectiveness are outlined. The following topics are discussed: human factors aspects of control room design; design of interactive systems; human computer dialogue, interaction tasks and techniques; guidelines on ergonomic aspects of control rooms and highly automated environments; system engineering for control by humans; conceptual models of information processing; information display and interaction in real time environments.

  14. A mock circulatory loop for designing and evaluating total artificial hearts.

    PubMed

    Love, Holley C; Timms, Daniel L; Nestler, Frank; Frazier, O H; Cohn, William E

    2014-01-01

    A mock circulatory loop was constructed to facilitate total artificial heart development. The loop includes many novel features such as a pressure-regulated tank to simulate exercise conditions, controllable systemic and pulmonary vascular resistance to create left-right flow imbalances as seen in postural change and breathing, and a left atrial suction valve. Dual HeartMate II pumps and the BiVACOR® rotary total artificial heart were used to generate pressure and flow data characterizing the flow loop.

  15. Human-system Interfaces for Automatic Systems

    SciTech Connect

    OHara, J.M.; Higgins,J.; Fleger, S.; Barnes V.

    2010-11-07

    Automation is ubiquitous in modern complex systems, and commercial nuclear- power plants are no exception. Automation is applied to a wide range of functions including monitoring and detection, situation assessment, response planning, and response implementation. Automation has become a 'team player' supporting personnel in nearly all aspects of system operation. In light of its increasing use and importance in new- and future-plants, guidance is needed to conduct safety reviews of the operator's interface with automation. The objective of this research was to develop such guidance. We first characterized the important HFE aspects of automation, including six dimensions: levels, functions, processes, modes, flexibility, and reliability. Next, we reviewed literature on the effects of all of these aspects of automation on human performance, and on the design of human-system interfaces (HSIs). Then, we used this technical basis established from the literature to identify general principles for human-automation interaction and to develop review guidelines. The guidelines consist of the following seven topics: automation displays, interaction and control, automation modes, automation levels, adaptive automation, error tolerance and failure management, and HSI integration. In addition, our study identified several topics for additional research.

  16. Summary of the British Transplantation Society guidelines for transplantation from donors after deceased circulatory death.

    PubMed

    Andrews, Peter A; Burnapp, Lisa; Manas, Derek

    2014-02-15

    The second edition of the British Transplantation Society Guidelines for Transplantation from Donors after Deceased Circulatory Death was published in June 2013. The guideline has been extensively revised since the previous edition in 2004 and has used the GRADE system to rate the strength of evidence and recommendations. This article summarizes the Statements of Recommendation contained in the guideline, which provide a framework for transplantation after deceased circulatory death in the U.K. and may be of wide international interest. It is recommended that the full guideline document is consulted for details of the relevant references and evidence base. This may be accessed at: http://www.bts.org.uk/MBR/Clinical/Guidelines/Current/Member/Clinical/Current_Guidelines.aspx.

  17. Evolving experience with mechanical circulatory support.

    PubMed Central

    Kormos, R L; Borovetz, H S; Armitage, J M; Hardesty, R L; Marrone, G C; Griffith, B P

    1991-01-01

    Since 1985 total mechanical circulatory support for mortally ill transplant candidates has been progressively integrated into the authors' program. During this period 379 patients underwent transplantation. Of this group of patients, 62 required some form of mechanical support other than the intra-aortic balloon pump. Because intra-aortic balloon pump assist was limited in therapeutic effect and was associated with patient immobility and line-related sepsis, the next logical step toward support was the artificial heart. Of 20 patients implanted with the Jarvik heart, 17 underwent transplantation, but only 9 of these survived to discharge. In 1988, the authors abandoned the preferential use of the total artificial heart because of excessive cumulative probability of death from wound infection. They began to use the Novacor electrical assist device with the percutaneous power cord because they believed that univentricular support would be adequate for most patients, because its heterotopic position would reduce the likelihood of infection, and because it had the potential for chronic implantation. Twenty-three patients with biventricular failure (right ventricular ejection fraction less than 20%, 18/23) received the electrical assist device for an average of 50.4 days (range 1-193 days). All 17 transplanted patients survived until discharge. Only one of the five deaths that occurred after implantation, but without transplantation, was due to infection (candidiasis). Remarkably, all patients who survived the perioperative period ultimately survived with univentricular support alone. Based on this experience, survival of mechanically supported patients is now comparable to that of those less mortally ill. Images Fig. 3. PMID:1953099

  18. Human nervous system function emulator.

    PubMed

    Frenger, P

    2000-01-01

    This paper describes a modular, extensible, open-systems design for a multiprocessor network which emulates the major functions of the human nervous system. Interchangeable hardware/software components, a socketed software bus with plug-and-play capability and self diagnostics are included. The computer hardware is based on IEEE P996.1 bus cards. Its operating system utilizes IEEE 1275 standard software. Object oriented design techniques and programming are featured. A machine-independent high level script-based command language was created for this project. Neural anatomical structures which were emulated include the cortex, brainstem, cerebellum, spinal cord, autonomic and peripheral nervous systems. Motor, sensory, autoregulatory, and higher cognitive artificial intelligence, behavioral and emotional functions are provided. The author discusses how he has interfaced this emulator to machine vision, speech recognition/speech synthesis, an artificial neural network and a dexterous hand to form an android robotic platform.

  19. Respiratory and circulatory effects of parietal pleural afferent stimulation in rabbits.

    PubMed

    Jammes, Yves; Delpierre, Stéphane

    2006-05-01

    Respiratory symptoms accompanying pleural diseases combine dyspnea, tachypnea, rapid shallow breathing, and sometimes hypotension. There are no experimental data on the changes in respiratory and circulatory functions elicited by the activation of pleural afferents. After removal of all muscles covering the 5th to 10th intercostal spaces, we investigated in paralyzed, vagotomized rabbits the changes in phrenic discharge, transpulmonary pressure, and systemic arterial pressure in response to an outwardly directed force exerted on the parietal pleura or the local application of solutions containing lactic acid or inflammatory mediators. Mechanical stimulation of the pleura induced an immediate decrease in both integrated phrenic discharge and arterial blood pressure, the responses being positively correlated with the magnitude of force applied on the pleura. No accompanying changes in ventilatory timing, transpulmonary pressure, or heart rate were measured. Lactic acid solution also elicited an inhibition of phrenic activity and a fall in blood pressure. Section of the internal intercostal nerves supplying the stimulated intercostal spaces totally abolished the responses to mechanical stimulation or lactic acid. An inflammatory mixture elicited only modest respiratory and circulatory effects. We concluded that an acute mechanical distension of the parietal pleura as well as its chemical stimulation by lactic acid elicit a marked inhibition of phrenic motoneurons combined to a reduction of the sympathetic outflow to the circulatory system.

  20. Description, validation, and modification of the Guyton model for space-flight applications. Part A. Guyton model of circulatory, fluid and electrolyte control. Part B. Modification of the Guyton model for circulatory, fluid and electrolyte control

    NASA Technical Reports Server (NTRS)

    Leonard, J. I.

    1985-01-01

    The mathematical model that has been a cornerstone for the systems analysis of space-flight physiological studies is the Guyton model describing circulatory, fluid and electrolyte regulation. The model and the modifications that are made to permit simulation and analysis of the stress of weightlessness are described.

  1. A Human Body Analysis System

    NASA Astrophysics Data System (ADS)

    Girondel, Vincent; Bonnaud, Laurent; Caplier, Alice

    2006-12-01

    This paper describes a system for human body analysis (segmentation, tracking, face/hands localisation, posture recognition) from a single view that is fast and completely automatic. The system first extracts low-level data and uses part of the data for high-level interpretation. It can detect and track several persons even if they merge or are completely occluded by another person from the camera's point of view. For the high-level interpretation step, static posture recognition is performed using a belief theory-based classifier. The belief theory is considered here as a new approach for performing posture recognition and classification using imprecise and/or conflicting data. Four different static postures are considered: standing, sitting, squatting, and lying. The aim of this paper is to give a global view and an evaluation of the performances of the entire system and to describe in detail each of its processing steps, whereas our previous publications focused on a single part of the system. The efficiency and the limits of the system have been highlighted on a database of more than fifty video sequences where a dozen different individuals appear. This system allows real-time processing and aims at monitoring elderly people in video surveillance applications or at the mixing of real and virtual worlds in ambient intelligence systems.

  2. Development of a hybrid (numerical-hydraulic) circulatory model: prototype testing and its response to IABP assistance.

    PubMed

    Ferrari, G; Kozarski, M; De Lazzari, C; Górczyńska, K; Tosti, G; Darowski, M

    2005-07-01

    Merging numerical and physical models of the circulation makes it possible to develop a new class of circulatory models defined as hybrid. This solution reduces the costs, enhances the flexibility and opens the way to many applications ranging from research to education and heart assist devices testing. In the prototype described in this paper, a hydraulic model of systemic arterial tree is connected to a lumped parameters numerical model including pulmonary circulation and the remaining parts of systemic circulation. The hydraulic model consists of a characteristic resistance, of a silicon rubber tube to allow the insertion of an Intra-Aortic Balloon Pump (IABP) and of a lumped parameters compliance. Two electro-hydraulic interfaces, realized by means of gear pumps driven by DC motors, connect the numerical section with both terminals of the hydraulic section. The lumped parameters numerical model and the control system (including analog to digital and digital to analog converters)are developed in LabVIEW environment. The behavior of the model is analyzed by means of the ventricular pressure-volume loops and the time courses of arterial and ventricular pressures and flows in different circulatory conditions. A simulated pathological condition was set to test the IABP and verify the response of the system to this type of mechanical circulatory assistance. The results show that the model can represent hemodynamic relationships in different ventricular and circulatory conditions and is able to react to the IABP assistance.

  3. Chronic low-dose exposure in the Techa River Cohort: risk of mortality from circulatory diseases.

    PubMed

    Krestinina, Lyudmila Yurievna; Epifanova, Svetlana; Silkin, Stanislav; Mikryukova, Lyudmila; Degteva, Marina; Shagina, Natalia; Akleyev, Alexander

    2013-03-01

    The aim of the present study was to analyze the mortality from circulatory diseases for about 30,000 members of the Techa River cohort over the period 1950-2003, and to investigate how these rates depend on radiation doses. This population received both external and internal exposures from (90)Sr, (89)Sr, (137)Cs, and other uranium fission products as a result of waterborne releases from the Mayak nuclear facility in the Southern Urals region of the Russian Federation. The analysis included individualized estimates of the total (external plus internal) absorbed dose in muscle calculated based on the Techa River Dosimetry System 2009. The cohort-average dose to muscle tissue was 35 mGy, and the maximum dose was 510 mGy. Between 1950 and 2003, 7,595 deaths from circulatory diseases were registered among cohort members with 901,563 person years at risk. Mortality rates in the cohort were analyzed using a simple parametric excess relative risk (ERR) model. For all circulatory diseases, the estimated excess relative risk per 100 mGy with a 15-year lag period was 3.6 % with a 95 % confidence interval of 0.2-7.5 %, and for ischemic heart disease it was 5.6 % with a 95 % confidence interval of 0.1-11.9 %. A linear ERR model provided the best fit. Analyses with a lag period shorter than 15 years from the beginning of exposure did not reveal any significant risk of mortality from either all circulatory diseases or ischemic heart disease. There was no evidence of an increased mortality risk from cerebrovascular disease (p > 0.5). These results should be regarded as preliminary, since they will be updated after adjustment for smoking and alcohol consumption.

  4. Circulatory contributors to the phenotype in hereditary hemorrhagic telangiectasia

    PubMed Central

    Shovlin, Claire L.

    2015-01-01

    Hereditary hemorrhagic telangiectasia (HHT) is mechanistically and therapeutically challenging, not only because of the molecular and cellular perturbations that generate vascular abnormalities, but also the modifications to circulatory physiology that result, and are likely to exacerbate vascular injury. First, most HHT patients have visceral arteriovenous malformations (AVMs). Significant visceral AVMs reduce the systemic vascular resistance: supra-normal cardiac outputs are required to maintain arterial blood pressure, and may result in significant pulmonary venous hypertension. Secondly, bleeding from nasal and gastrointestinal telangiectasia leads to iron losses of such magnitude that in most cases, diet is insufficient to meet the ‘hemorrhage adjusted iron requirement.’ Resultant iron deficiency restricts erythropoiesis, leading to anemia and further increases in cardiac output. Low iron levels are also associated with venous and arterial thromboses, elevated Factor VIII, and increased platelet aggregation to circulating 5HT (serotonin). Third, recent data highlight that reduced oxygenation of blood due to pulmonary AVMs results in a graded erythrocytotic response to maintain arterial oxygen content, and higher stroke volumes and/or heart rates to maintain oxygen delivery. Finally, HHT-independent factors such as diet, pregnancy, sepsis, and other intercurrent illnesses also influence vascular structures, hemorrhage, and iron handling in HHT patients. These considerations emphasize the complexity of mechanisms that impact on vascular structures in HHT, and also offer opportunities for targeted therapeutic approaches. PMID:25914716

  5. Peripheral biomarkers of stroke: Focus on circulatory microRNAs.

    PubMed

    Vijayan, Murali; Reddy, P Hemachandra

    2016-10-01

    Stroke is the second leading cause of death in the world. Stroke occurs when blood flow stops, and that stoppage results in reduced oxygen supply to neurons in the brain. The occurrence of stroke increases with age, but anyone at any age can suffer from stroke. Recent research has implicated multiple cellular changes in stroke patients, including oxidative stress and mitochondrial dysfunction, inflammatory responses, and changes in mRNA and proteins. Recent research has also revealed that stroke is associated with modifiable and non-modifiable risk factors. Stroke can be controlled by modifiable risk factors, including diet, cardiovascular, hypertension, smoking, diabetes, obesity, metabolic syndrome, depression and traumatic brain injury. Stroke is the major risk factor for vascular dementia (VaD) and Alzheimer's disease (AD). The purpose of this article is to review the latest developments in research efforts directed at identifying 1) latest developments in identifying biomarkers in peripheral and central nervous system tissues, 2) changes in microRNAs (miRNAs) in patients with stroke, 3) miRNA profile and function in animal brain, and 4) protein biomarkers in ischemic stroke. This article also reviews research investigating circulatory miRNAs as peripheral biomarkers of stroke. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Scale-space analysis of time series in circulatory research.

    PubMed

    Mortensen, Kim Erlend; Godtliebsen, Fred; Revhaug, Arthur

    2006-12-01

    Statistical analysis of time series is still inadequate within circulation research. With the advent of increasing computational power and real-time recordings from hemodynamic studies, one is increasingly dealing with vast amounts of data in time series. This paper aims to illustrate how statistical analysis using the significant nonstationarities (SiNoS) method may complement traditional repeated-measures ANOVA and linear mixed models. We applied these methods on a dataset of local hepatic and systemic circulatory changes induced by aortoportal shunting and graded liver resection. We found SiNoS analysis more comprehensive when compared with traditional statistical analysis in the following four ways: 1) the method allows better signal-to-noise detection; 2) including all data points from real time recordings in a statistical analysis permits better detection of significant features in the data; 3) analysis with multiple scales of resolution facilitates a more differentiated observation of the material; and 4) the method affords excellent visual presentation by combining group differences, time trends, and multiscale statistical analysis allowing the observer to quickly view and evaluate the material. It is our opinion that SiNoS analysis of time series is a very powerful statistical tool that may be used to complement conventional statistical methods.

  7. Mechanical Circulatory Support of the Critically Ill Child Awaiting Heart Transplantation

    PubMed Central

    Gazit, Avihu Z; Gandhi, Sanjiv K; C Canter, Charles

    2010-01-01

    The majority of children awaiting heart transplantation require inotropic support, mechanical ventilation, and/or extracorporeal membrane oxygenation (ECMO) support. Unfortunately, due to the limited pool of organs, many of these children do not survive to transplant. Mechanical circulatory support of the failing heart in pediatrics is a new and rapidly developing field world-wide. It is utilized in children with acute congestive heart failure associated with congenital heart disease, cardiomyopathy, and myocarditis, both as a bridge to transplantation and as a bridge to myocardial recovery. The current arsenal of mechanical assist devices available for children is limited to ECMO, intra-aortic balloon counterpulsation, centrifugal pump ventricular assist devices, the DeBakey ventricular assist device Child; the Thoratec ventricular assist device; and the Berlin Heart. In the spring of 2004, five contracts were awarded by the National Heart, Lung and Blood Institute to support preclinical development for a range of pediatric ventricular assist devices and similar circulatory support systems. The support of early development efforts provided by this program is expected to yield several devices that will be ready for clinical trials within the next few years. Our work reviews the current international experience with mechanical circulatory support in children and summarizes our own experience since 2005 with the Berlin Heart, comparing the indications for use, length of support, and outcome between these modalities. PMID:21286278

  8. Pathophysiological Trends During Withdrawal of Life Support: Implications for Organ Donation After Circulatory Death.

    PubMed

    Iyer, Arjun; Chew, Hong Chee; Gao, Ling; Villanueva, Jeanette; Hicks, Mark; Doyle, Aoife; Kumarasinghe, Gayathri; Jabbour, Andrew; Jansz, Paul Cassius; Feneley, Michael P; Harvey, Richard P; Graham, Robert M; Dhital, Kumud K; Macdonald, Peter S

    2016-12-01

    Donation after circulatory death (DCD) provides an alternative pathway to deceased organ transplantation. Although clinical DCD lung, liver, and kidney transplantation are well established, transplantation of hearts retrieved from DCD donors has reached clinical translation only recently. Progress has been limited by concern regarding the viability of DCD hearts. The aim of this study was to document the pathophysiological changes that occur in the heart and circulation during withdrawal of life (WLS) support. In a porcine asphyxia model, we characterized the hemodynamic, volumetric, metabolic, biochemical, and endocrine changes after WLS for up to 40 minutes. Times to circulatory arrest and electrical asystole were recorded. After WLS, there was rapid onset of profound hypoxemia resulting in acute pulmonary hypertension and right ventricular distension. Concurrently, progressive systemic hypotension occurred with a fall in left atrial pressure and little change in left ventricular volume. Mean times to circulatory arrest and electrical asystole were 8 ± 1 and 16 ± 2 minutes, respectively. Hemodynamic changes were accompanied by a rapid fall in pH, and rise in blood lactate, troponin-T, and potassium. Plasma noradrenaline and adrenaline levels rose rapidly with dramatic increases in coronary sinus levels indicative of myocardial release. These findings provide insight into the nature and tempo of the damaging events that occur in the heart and in particular the right ventricle during WLS, and give an indication of the limited timeframe for the implementation of potential postmortem interventions that could be applied to improve organ viability.

  9. High-risk medical devices, children and the FDA: regulatory challenges facing pediatric mechanical circulatory support devices.

    PubMed

    Almond, Christopher S D; Chen, Eric A; Berman, Michael R; Less, Joanne R; Baldwin, J Timothy; Linde-Feucht, Sarah R; Hoke, Tracey R; Pearson, Gail D; Jenkins, Kathy; Duncan, Brian W; Zuckerman, Bram D

    2007-01-01

    Pediatric mechanical circulatory support is a critical unmet need in the United States. Infant- and child-sized ventricular assist devices are currently being developed largely through federal contracts and grants through the National Heart, Lung, and Blood Institute (NHLBI). Human testing and marketing of high-risk devices for children raises epidemiologic and regulatory issues that will need to be addressed. Leaders from the US Food and Drug Administration (FDA), NHLBI, academic pediatric community, and industry convened in January 2006 for the first FDA Workshop on the Regulatory Process for Pediatric Mechanical Circulatory Support Devices. The purpose was to provide the pediatric community with an overview of the federal regulatory process for high-risk medical devices and to review the challenges specific to the development and regulation of pediatric mechanical circulatory support devices. Pediatric mechanical circulatory support present significant epidemiologic, logistic, and financial challenges to industry, federal regulators, and the pediatric community. Early interactions with the FDA, shared appreciation of challenges, and careful planning will be critical to avoid unnecessary delays in making potentially life-saving devices available for children. Collaborative efforts to address these challenges are warranted.

  10. Current status of cardiac transplantation and mechanical circulatory support.

    PubMed

    Boyle, Andrew

    2009-03-01

    Cardiac transplantation and mechanical circulatory support are possible options for improving survival and quality of life in patients with isolated cardiac disease and end-stage heart failure. Transplantation is limited by donor availability but has a median survival of 10 years. Post-transplant immunosuppression is often transplant center dependent, but a tacrolimus and mycophenolate mofetil-based regimen may be preferred. Sirolimus may reduce the progression rate of transplant vasculopathy. There has been a trend toward continuous-flow left ventricular assist devices because of their increased durability and reduced size. A variety of surgical and percutaneous ventricular assist devices may be used as a bridge to decision on a patient's candidacy for transplantation. Mechanical circulatory support as destination therapy has not been widely implemented because of poor device durability, but this is expected to change with newer devices. Mechanical circulatory support as a bridge to myocardial recovery has been successful only in a few patients.

  11. Circulatory death determination in uncontrolled organ donors: a panel viewpoint.

    PubMed

    Bernat, James L; Bleck, Thomas P; Blosser, Sandralee A; Bratton, Susan L; Capron, Alexander M; Cornell, Danielle; DeVita, Michael A; Fulda, Gerard J; Glazier, Alexandra K; Gries, Cynthia J; Mathur, Mudit; Nakagawa, Thomas A; Shemie, Sam D

    2014-04-01

    One barrier for implementing programs of uncontrolled organ donation after the circulatory determination of death is the lack of consensus on the precise moment of death. Our panel was convened to study this question after we performed a similar analysis on the moment of death in controlled organ donation after the circulatory determination of death. We concluded that death could be determined by showing the permanent or irreversible cessation of circulation and respiration. Circulatory irreversibility may be presumed when optimal cardiopulmonary resuscitation efforts have failed to restore circulation and at least a 7-minute period has elapsed thereafter during which autoresuscitation to restored circulation could occur. We advise against the use of postmortem organ support technologies that reestablish circulation of warm oxygenated blood because of their risk of retroactively invalidating the required conditions on which death was declared.

  12. H2S during circulatory shock: Some unresolved questions

    PubMed Central

    McCook, Oscar; Radermacher, Peter; Volani, Chiara; Asfar, Pierre; Ignatius, Anita; Kemmler, Julia; Möller, Peter; Szabó, Csaba; Whiteman, Matthew; Wood, Mark E.; Wang, Rui; Georgieff, Michael; Wachter, Ulrich

    2014-01-01

    Numerous papers have been published on the role of H2S during circulatory shock. Consequently, knowledge about vascular sulfide concentrations may assume major importance, in particular in the context of “acute on chronic disease”, i.e., during circulatory shock in animals with pre-existing chronic disease. This review addresses the questions i) of the “real” sulfide levels during circulatory shock, and, ii) to which extent injury and pre-existing co-morbidity may affect the expression of H2S producing enzymes under these conditions. In the literature there is a huge range on sulfide blood levels during circulatory shock, in part as a result of the different analytical methods used, but also due to the variable of the models and species studied. Clearly, some of the very high levels reported should be questioned in the context of the well-known H2S toxicity. As long as “real” sulfide levels during circulatory shock are unknown and/or undetectable “on line” due to the lack of appropriate techniques, it appears to be premature to correlate the measured blood levels of hydrogen sulfide with the severity of shock or the H2S therapy-related biological outcomes. The available data on the tissue expression of the H2S-releasing enzymes during circulatory shock suggest that a “constitutive” CSE expression may play a crucial role of for the maintenance of organ function, at least in the kidney. The data also indicate that increased CBS and CSE expression, in particular in the lung and the liver, represents an adaptive response to stress states. PMID:24650697

  13. Risk Factors and Outcomes in Transfusion-associated Circulatory Overload

    PubMed Central

    Murphy, Edward L.; Kwaan, Nicholas; Looney, Mark R.; Gajic, Ognjen; Hubmayr, Rolf D.; Gropper, Michael A.; Koenigsberg, Monique; Wilson, Greg; Matthay, Michael; Bacchetti, Peter; Toy, Pearl

    2013-01-01

    BACKGROUND Transfusion-associated circulatory overload is characterized by new respiratory distress and hydrostatic pulmonary edema within 6 hours after blood transfusion, but its risk factors and outcomes are poorly characterized. METHODS Using a case control design, we enrolled 83 patients with severe transfusion-associated circulatory overload identified by active surveillance for hypoxemia and 163 transfused controls at the University of California, San Francisco (UCSF) and Mayo Clinic (Rochester, Minn) hospitals. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable logistic regression, and survival and length of stay were analyzed using proportional hazard models. RESULTS Transfusion-associated circulatory overload was associated with chronic renal failure (OR 27.0; 95% CI, 5.2–143), a past history of heart failure (OR 6.6; 95% CI, 2.1–21), hemorrhagic shock (OR 113; 95% CI, 14.1–903), number of blood products transfused (OR 1.11 per unit; 95% CI, 1.01–1.22), and fluid balance per hour (OR 9.4 per liter; 95% CI, 3.1–28). Patients with transfusion-associated circulatory overload had significantly increased in-hospital mortality (hazard ratio 3.20; 95% CI, 1.23–8.10) after controlling for Acute Physiology and Chronic Health Evaluation-II (APACHE-II) score, and longer hospital and intensive care unit lengths of stay. CONCLUSIONS The risk of transfusion-associated circulatory overload increases with the number of blood products administered and a positive fluid balance, and in patients with pre-existing heart failure and chronic renal failure. These data, if replicated, could be used to construct predictive algorithms for transfusion-associated circulatory overload, and subsequent modifications of transfusion practice might prevent morbidity and mortality associated with this complication. PMID:23357450

  14. Next generation OP-bioscavengers: a circulatory long-lived 4-PEG hypolysine mutant of F338A-HuAChE with optimal pharmacokinetics and pseudo-catalytic characteristics.

    PubMed

    Kronman, Chanoch; Cohen, Ofer; Mazor, Ohad; Ordentlich, Arie; Raveh, Lily; Velan, Baruch; Shafferman, Avigdor

    2010-09-06

    We have shown previously that conjugation of polyethylene glycol (PEG) chains to recombinant human acetylcholinesterase (rHuAChE) results in the extension of its residence time in the circulation of mice and monkeys [1,2]. By profiling the pharmacokinetic behavior of an array of well-defined hypolysine human mutant AChE molecules following PEGylation, we now determine that the duration of these enzyme forms in the circulation of rhesus macaques correlates with their number of appended PEG moieties, and is influenced by the actual location of the PEG chains at the molecule surface, as well. These findings, which concur with those we have previously established in mice, indicate that a common set of rules dictates the circulatory fate of PEGylated HuAChEs in rodents and non-human primates. In addition to its effect on circulatory residence, PEGylation reduces the ability of the rHuAChE bioscavenger to elicit an immune response in the heterologous mouse animal system. Thus, an inverse relationship between anti-AChE antibody production and PEG loading was observed following repeated administration of the different PEGylated hypolysine human AChEs to mice. We note however, that in rhesus macaques, the essentially homologous (human) AChE does not induce specific anti-AChE antibodies after repeated administration of high doses of the enzyme in its PEGylated form, and even in its non-PEGylated form. Taken together, these findings indicate that PEG acts by veiling enzyme-related epitopes, which would otherwise interact with host circulatory elimination pathways and immune system. The barring of such interactions by obstructive PEGs, confers the enzyme molecule with both extended circulatory residence and mitigated immunogenic properties. Further modulation by incorporation of the F338A mutation into the PEGylated hypolysine rHuAChE enzyme mold, resulted in the generation of an OP-bioscavenger that displayed reduced aging rates and could effectively protect mice against

  15. Is moderate hypothermic circulatory arrest with selective antegrade cerebral perfusion superior to deep hypothermic circulatory arrest in elective aortic arch surgery?

    PubMed

    Poon, Shi Sum; Estrera, Anthony; Oo, Aung; Field, Mark

    2016-09-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether moderate hypothermia circulatory arrest with selective antegrade cerebral perfusion (SACP) is more beneficial than deep hypothermic circulatory arrest in elective aortic arch surgery. Altogether, 1028 papers were found using the reported search, of which 6 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. There were four retrospective observational studies, one prospective randomized controlled trial and one meta-analysis study. There were no local or neuromuscular complications related to axillary arterial cannulation reported. In the elective setting, four studies showed that the in-hospital mortality for moderate hypothermia is consistently low, ranging from 1.0 to 4.3%. In a large series of hemiarch replacement comparing 682 cases of deep hypothermia with 94 cases of moderate hypothermia with SACP, 20 cases (2.8%) of permanent neurological deficit were reported, compared to 3 cases (3.2%) in moderate hypothermia. Three observational studies and a meta-analysis study did not identify an increased risk of postoperative renal failure and dialysis following either deep or moderate hypothermia although a higher incidence of stroke was reported in the meta-analysis study with deep hypothermia (12.7 vs 7.3%). Longer cardiopulmonary bypass time and circulatory arrest time were reported in four studies for deep hypothermia, suggesting an increased time required for systemic cooling and rewarming in that group. Overall, these findings suggested that in elective aortic arch surgery, moderate hypothermia with selective antegrade cerebral perfusion adapted to the duration of circulatory arrest can be performed safely with acceptable mortality and morbidity outcomes. The risk of spinal cord

  16. The quantum human central neural system.

    PubMed

    Alexiou, Athanasios; Rekkas, John

    2015-01-01

    In this chapter we present Excess Entropy Production for human aging system as the sum of their respective subsystems and electrophysiological status. Additionally, we support the hypothesis of human brain and central neural system quantumness and we strongly suggest the theoretical and philosophical status of human brain as one of the unknown natural Dirac magnetic monopoles placed in the center of a Riemann sphere.

  17. Architecting Systems for Human Space Flight

    NASA Technical Reports Server (NTRS)

    Wocken, Gerald

    2002-01-01

    Human-system interactions have been largely overlooked in the traditional systems engineering process. Awareness of human factors (HF) has increased in the past few years, but the involvement of HF specialists is still often too little and too late. In systems involving long-duration human space flight, it is essential that the human component be properly considered in the initial architectural definition phase, as well as throughout the system design process. HF analysis must include not only the strengths and limitations of humans in general, but the variability between individuals and within an individual over time, and the dynamics of group interactions.

  18. Mechanical circulatory support for elderly heart failure patients.

    PubMed

    Butler, Craig R; Jugdutt, Bodh I

    2012-09-01

    End-stage systolic heart failure is an increasingly common problem in elderly patients and is associated with high cost, poor quality of life, and poor outcomes. Mechanical circulatory support is a promising therapy as both a bridge to transplantation and destination therapy. Elderly patients are frequently ineligible for heart transplantation because of their age and comorbidities, and the application of mechanical circulatory support for destination therapy in this population is not well defined. A review of the literature was undertaken to better characterize our experience to date with mechanical circulatory support in older heart failure populations. Mechanical circulatory support is being employed increasingly for destination therapy indications in older patients. The newer continuous flow devices appear to have disproportionate advantage in elderly patients, which has translated into marked improvement in 1- and 2-year survival. The rational implementation of MCS devices in elderly heart failure patients needs to focus on (1) continuous flow devices that appear to have particular benefit in this population, (2) extensive pre-MCS assessment including variables relating to frailty, and (3) intervening before these patients develop cardiogenic shock. More data are needed on the cost-benefit analysis of routine use of CF devices as destination therapy in elderly patients with heart failure.

  19. Optical spectroscopic assessment of free flap circulatory impairment

    NASA Astrophysics Data System (ADS)

    Sowa, Michael G.; Payette, Jeri R.; Kohlenberg, Elicia; Leonardi, Lorenzo; Pabbies, Arone; Kerr, Paul

    2004-10-01

    Free flaps are used to reconstruct tissue damaged by injury. Circulatory impairment of the free flap is the leading cause of a failed flap surgery. This study demonstrates that optical spectroscopy can detect early signs of circulatory impairment and distinguish between arterial or venous blockage. An epigastric flap model is used to mimic conditions of both arterial and venous circulatory impairment. Animals were divided into three groups 1.) arterial occlusion (n=5), 2.) venous occlusion (n=4), and 3.) control (n=5). A classifier was applied to the reflectance data to determine whether there were consistent differences between the three study groups. The classifier was able to distinguish between arterial occlusion, venous occlusion and healthy flaps with a 95% accuracy. Measures of hemoglobin oxygen saturation and blood volume were derived from the same reflectance data. Oxygenation of the flap was significantly lower during venous or arterial occlusion compared to control flaps. Blood volume of the free flap went up significantly following venous blockage while blockage of the artery cause a significant drop in blood volume. Combining the predictions of the classifier and examining the oxygenation and blood volume parameters reliably detected circulatory impairment of the free flap.

  20. Mechanical circulatory support for infants and small children.

    PubMed

    Gournay, Véronique; Hauet, Quentin

    2014-01-01

    The number of children in need of mechanical circulatory support has increased substantially over the last two decades, due to the technological progress made in surgery and intensive care, leading to improved survival of patients with congenital heart disease. In addition, primary myocardial dysfunction related to myocarditis or dilated cardiomyopathy may cause end-stage cardiac failure in children or infants, although not as frequently as in adults. The need for mechanical circulatory support may be either temporary until spontaneous myocardial recovery, as in postcardiotomy cardiac failure, or prolonged until heart transplantation in the absence of recovery. Two types of mechanical circulatory devices are suitable for the paediatric population: extracorporeal membrane oxygenation for short-term support; and ventricular assist devices for long-term support as a bridge to transplantation. The aim of this review is to describe the specific issues related to paediatric mechanical circulatory support and the different types of devices available, to report on their rapidly growing use worldwide and on the outcomes for each indication and type of device, and to provide a perspective on the future developments and remaining challenges in this field.

  1. Belgian modified classification of Maastricht for donors after circulatory death.

    PubMed

    Evrard, P

    2014-11-01

    "Non-heart-beating donors," or, in a more recent and international definition, "donors after circulatory death," are a potential and additional group of deceased persons who are able to add organs to the pool. A new classification is proposed on the basis of the result of a consensus of experts issued from all Belgian transplant centers. The first level of definition is simple and based on whether the situation is uncontrolled (categories I and II) or controlled (categories III, IV, and V). In category I, the patient is declared "dead on arrival" and, in category II, there is an "unsuccessful resuscitation" whether it occurred out or in the hospital for both situations. Category III is the most usual situation in which the treating physician and family are "awaiting cardiac arrest" to declare the death of the patient. Category IV is always characterized by "cardiac arrest during brain death." The special situation of the Belgian law allowing the euthanasia is elaborated in category V, "euthanasia," and includes patients who grant access to medically assisted circulatory death. Organ donation after euthanasia is allowed under the scope of donation after circulatory death. This classification conserves the skeleton of the Maastricht one, as it is simple and clear, but classifies easily the different donors after circulatory death types by processes for ethical issues and for the non-medical or non-specialized reader interested in the field. This is also an argument for public consideration and trust in the difficult field of organ donation.

  2. Circulatory disease mortality in the Massachusetts tuberculosis fluoroscopy cohort study.

    PubMed

    Little, Mark P; Zablotska, Lydia B; Brenner, Alina V; Lipshultz, Steven E

    2016-03-01

    High-dose ionizing radiation is associated with circulatory disease. Risks from lower-dose fractionated exposures, such as from diagnostic radiation procedures, remain unclear. In this study we aimed to ascertain the relationship between fractionated low-to-medium dose radiation exposure and circulatory disease mortality in a cohort of 13,568 tuberculosis patients in Massachusetts, some with fluoroscopy screenings, between 1916 and 1961 and follow-up until the end of 2002. Analysis of mortality was in relation to cumulative thyroid (cerebrovascular) or lung (all other circulatory disease) radiation dose via Poisson regression. Over the full dose range, there was no overall radiation-related excess risk of death from circulatory disease (n = 3221; excess relative risk/Gy -0.023; 95% CI -0.067, 0.028; p = 0.3574). Risk was somewhat elevated in hypertensive heart disease (n = 89; excess relative risk/Gy 0.357; 95% CI -0.043, 1.030, p = 0.0907) and slightly decreased in ischemic heart disease (n = 1950; excess relative risk/Gy -0.077; 95% CI -0.130, -0.012; p = 0.0211). However, under 0.5 Gy, there was a borderline significant increasing trend for all circulatory disease (excess relative risk/Gy 0.345; 95% CI -0.032, 0.764; p = 0.0743) and for ischemic heart disease (excess relative risk/Gy 0.465; 95% CI, -0.032, 1.034, p = 0.0682). Pneumolobectomy increased radiation-associated risk (excess relative risk/Gy 0.252; 95% CI 0.024, 0.579). Fractionation of dose did not modify excess risk. In summary, we found no evidence of radiation-associated excess circulatory death risk overall, but there are indications of excess circulatory death risk at lower doses (<0.5 Gy). Although consistent with other radiation-exposed groups, the indications of higher risk at lower doses are unusual and should be confirmed against other data.

  3. Feedbacks in human-landscape systems.

    PubMed

    Chin, Anne; Florsheim, Joan L; Wohl, Ellen; Collins, Brian D

    2014-01-01

    This article identifies key questions and challenges for geomorphologists in investigating coupled feedbacks in human-landscape systems. While feedbacks occur in the absence of human influences, they are also altered by human activity. Feedbacks are a key element to understanding human-influenced geomorphic systems in ways that extend our traditional approach of considering humans as unidirectional drivers of change. Feedbacks have been increasingly identified in Earth-environmental systems, with studies of coupled human-natural systems emphasizing ecological phenomena in producing emerging concepts for social-ecological systems. Enormous gaps or uncertainties in knowledge remain with respect to understanding impact-feedback loops within geomorphic systems with significant human alterations, where the impacted geomorphic systems in turn affect humans. Geomorphology should play an important role in public policy by identifying the many diffuse and subtle feedbacks of both local- and global-scale processes. This role is urgent, while time may still be available to mitigate the impacts that limit the sustainability of human societies. Challenges for geomorphology include identification of the often weak feedbacks that occur over varied time and space scales ranging from geologic time to single isolated events and very short time periods, the lack of available data linking impact with response, the identification of multiple thresholds that trigger feedback mechanisms, the varied tools and metrics needed to represent both physical and human processes, and the need to collaborate with social scientists with expertise in the human causes of geomorphic change, as well as the human responses to such change.

  4. Feedbacks in Human-Landscape Systems

    NASA Astrophysics Data System (ADS)

    Chin, Anne; Florsheim, Joan L.; Wohl, Ellen; Collins, Brian D.

    2014-01-01

    This article identifies key questions and challenges for geomorphologists in investigating coupled feedbacks in human-landscape systems. While feedbacks occur in the absence of human influences, they are also altered by human activity. Feedbacks are a key element to understanding human-influenced geomorphic systems in ways that extend our traditional approach of considering humans as unidirectional drivers of change. Feedbacks have been increasingly identified in Earth-environmental systems, with studies of coupled human-natural systems emphasizing ecological phenomena in producing emerging concepts for social-ecological systems. Enormous gaps or uncertainties in knowledge remain with respect to understanding impact-feedback loops within geomorphic systems with significant human alterations, where the impacted geomorphic systems in turn affect humans. Geomorphology should play an important role in public policy by identifying the many diffuse and subtle feedbacks of both local- and global-scale processes. This role is urgent, while time may still be available to mitigate the impacts that limit the sustainability of human societies. Challenges for geomorphology include identification of the often weak feedbacks that occur over varied time and space scales ranging from geologic time to single isolated events and very short time periods, the lack of available data linking impact with response, the identification of multiple thresholds that trigger feedback mechanisms, the varied tools and metrics needed to represent both physical and human processes, and the need to collaborate with social scientists with expertise in the human causes of geomorphic change, as well as the human responses to such change.

  5. Fundamentals of systems ergonomics/human factors.

    PubMed

    Wilson, John R

    2014-01-01

    Ergonomics/human factors is, above anything else, a systems discipline and profession, applying a systems philosophy and systems approaches. Many things are labelled as system in today's world, and this paper specifies just what attributes and notions define ergonomics/human factors in systems terms. These are obviously a systems focus, but also concern for context, acknowledgement of interactions and complexity, a holistic approach, recognition of emergence and embedding of the professional effort involved within organization system. These six notions are illustrated with examples from a large body of work on rail human factors.

  6. Human Factors Interface with Systems Engineering for NASA Human Spaceflights

    NASA Technical Reports Server (NTRS)

    Wong, Douglas T.

    2009-01-01

    This paper summarizes the past and present successes of the Habitability and Human Factors Branch (HHFB) at NASA Johnson Space Center s Space Life Sciences Directorate (SLSD) in including the Human-As-A-System (HAAS) model in many NASA programs and what steps to be taken to integrate the Human-Centered Design Philosophy (HCDP) into NASA s Systems Engineering (SE) process. The HAAS model stresses systems are ultimately designed for the humans; the humans should therefore be considered as a system within the systems. Therefore, the model places strong emphasis on human factors engineering. Since 1987, the HHFB has been engaging with many major NASA programs with much success. The HHFB helped create the NASA Standard 3000 (a human factors engineering practice guide) and the Human Systems Integration Requirements document. These efforts resulted in the HAAS model being included in many NASA programs. As an example, the HAAS model has been successfully introduced into the programmatic and systems engineering structures of the International Space Station Program (ISSP). Success in the ISSP caused other NASA programs to recognize the importance of the HAAS concept. Also due to this success, the HHFB helped update NASA s Systems Engineering Handbook in December 2007 to include HAAS as a recommended practice. Nonetheless, the HAAS model has yet to become an integral part of the NASA SE process. Besides continuing in integrating HAAS into current and future NASA programs, the HHFB will investigate incorporating the Human-Centered Design Philosophy (HCDP) into the NASA SE Handbook. The HCDP goes further than the HAAS model by emphasizing a holistic and iterative human-centered systems design concept.

  7. Mock Circulatory Loop Compliance Chamber Employing a Novel Real-Time Control Process.

    PubMed

    Taylor, Charles E; Miller, Gerald E

    2012-12-01

    The use of compliance chambers in mock circulatory loop construction is the predominant means of simulating arterial compliance. Utilizing mock circulatory loops as bench test methods for cardiac assist technologies necessitates that they must be capable of reproducing the circulatory conditions that would exist physiologically. Of particular interest is the ability to determine instantaneous compliance of the system, and the ability to change the compliance in real-time. This capability enables continuous battery testing of conditions without stopping the flow to change the compliance chamber settings, and the simulation of dynamic changes in arterial compliance. The method tested involves the use of a compliance chamber utilizing a circular natural latex rubber membrane separating the fluid and air portions of the device. Change in system compliance is affected by the airspace pressure, which creates more reaction force at the membrane to the fluid pressure. A pressure sensor in the fluid portion of the chamber and a displacement sensor monitoring membrane center deflection allow for real-time inputs to the control algorithm. A predefined numerical model correlates the displacement sensor data to the volume displacement of the membrane. The control algorithm involves a tuned π loop maintaining the volume distention of the membrane via regulation of the air space pressure. The proportional integral (PI) controller tuning was achieved by creating a computational model of the compliance chamber using Simulink™ Simscape(®) toolboxes. These toolboxes were used to construct a model of the hydraulic, mechanical, and pneumatic elements in the physical design. Parameter Estimation™ tools and Design Optimization™ methods were employed to determine unknown physical parameters in the system, and tune the process controller used to maintain the compliance setting. It was found that the resulting control architecture was capable of maintaining compliance along a

  8. Heart Failure as a Disruption of Dynamic Circulatory Homeostasis Mediated by the Brain.

    PubMed

    Kishi, Takuya

    2016-01-01

    Circulatory homeostasis is associated with interactions between multiple organs, and the disruption of dynamic circulatory homeostasis could be considered as heart failure. The brain is the central unit integrating neural and neurohormonal information from peripheral organs and controlling peripheral organs using the autonomic nervous system. Heart failure is worsened by abnormal sympathoexcitation associated with baroreflex failure and/or chemoreflex activation, and by vagal withdrawal, and autonomic modulation therapies have benefits for heart failure. Recently, we showed that baroreflex failure induces striking volume intolerance independent of left ventricular dysfunction. Many studies have indicated that an overactive renin-angiotensin system, excess oxidative stress and excess inflammation, and/or decreased nitric oxide in the brain cause sympathoexcitation in heart failure. We have demonstrated that angiotensin II type 1 receptor (AT1R)-induced oxidative stress in the rostral ventrolateral medulla (RVLM), which is known as a vasomotor center, causes prominent sympathoexcitation in heart failure model rats. Interestingly, systemic infusion of angiotensin II directly affects brain AT1R with sympathoexcitation and left ventricular diastolic dysfunction. Moreover, we have demonstrated that targeted deletion of AT1R in astrocytes strikingly improved survival with prevention of left ventricular remodeling and sympathoinhibition in myocardial infarction-induced heart failure. From these results, we believe it is possible that AT1R in astrocytes, not in neurons, have a key role in the pathophysiology of heart failure. We would like to propose a novel concept that the brain works as a central processing unit integrating neural and hormonal input, and that the disruption of dynamic circulatory homeostasis mediated by the brain causes heart failure.

  9. APPLICATION OF OPTIMAL CONTROL THEORY TO CARDIO-CIRCULATORY ASSIST DEVICES.

    DTIC Science & Technology

    The objective of the investigation is the application of, and where necessary, extension of optimal control theory to the synthesis of controllers for such cardio-circulatory assist devices. In particular, the concept of set of attainability is extended to include linear, periodic, bounded control systems and the maximum principle applied to obtain necessary and sufficient conditions for various problems. In addition to several numerical examples, the results of a large-scale hybrid simulation for a cardiovascular model and particular assist device are presented.

  10. Energy transmission and power sources for mechanical circulatory support devices to achieve total implantability.

    PubMed

    Wang, Jake X; Smith, Joshua R; Bonde, Pramod

    2014-04-01

    Left ventricular assist device therapy has radically improved congestive heart failure survival with smaller rotary pumps. The driveline used to power today's left ventricular assist devices, however, continues to be a source of infection, traumatic damage, and rehospitalization. Previous attempts to wirelessly power left ventricular assist devices using transcutaneous energy transfer systems have been limited by restrictions on separation distance and alignment between the transmit and receive coils. Resonant electrical energy transfer allows power delivery at larger distances without compromising safety and efficiency. This review covers the efforts to wirelessly power mechanical circulatory assist devices and the progress made in enhancing their energy sources.

  11. The Sodium Paradox: Dysnatremia and Mortality in Patients Implanted With Extracorporeal Mechanical Circulatory Support Devices.

    PubMed

    Yost, Gardner; Tatooles, Antone; Bhat, Geetha

    2016-09-20

    Dysnatremia, abnormal serum sodium levels, has long been used as a marker for disease progression in heart failure patients. Classically, hyponatremia is associated with increased fluid volume in heart failure and is often a result of neuroendocrine dysfunction and poor cardiac output. Recent studies have noted that dysnatremia and hypernatremia are predictive of worsened outcomes in critical care and renal disease populations. We investigated the relationship between dysnatremia and postoperative outcomes in patients implanted with extracorporeal mechanical circulatory devices. A total of 97 patients who underwent implantation with the CentriMag mechanical circulatory assist system were included in this retrospective study. Patients were divided into 2 groups based on preoperative serum sodium level cutoff of 135 mEq/L. Outcomes and mortality were compared between groups. The mean age for the study population was 56.21 ± 15.13 years, and 57 patients (58.8%) were male. The mean time on CentriMag support was 22.7 days. Patients with serum sodium levels ≤135 mEq/L were noted to have significantly worsened indicators of preoperative cardiac function. However, patients with serum sodium levels >135 mEq/L had significantly shorter postoperative survival (P = .006). When entered into a multivariate Cox proportional hazards model, sodium was an independent predictor for increased risk of mortality (hazard ratio: 1.224; 95% confidence interval: 1.009-1.485; P = .040). Our results indicate that elevated preoperative sodium in patients undergoing implantation of a temporary mechanical circulatory support system is predictive of worsened postoperative survival. © The Author(s) 2016.

  12. Modeling human-environmental systems

    Treesearch

    Morgan Grove; Charlie Schweik; Tom Evans; Glen Green

    2002-01-01

    This chapter focuses on the integration and development of environmental models that include human decision making. While many methodological and technical issues are common to all types of environmental models, our goal is to highlight the unique characteristics that need to be considered when modeling human-environmental dynamics and to identify future directions for...

  13. The Human-Robot Interaction Operating System

    NASA Technical Reports Server (NTRS)

    Fong, Terrence; Kunz, Clayton; Hiatt, Laura M.; Bugajska, Magda

    2006-01-01

    In order for humans and robots to work effectively together, they need to be able to converse about abilities, goals and achievements. Thus, we are developing an interaction infrastructure called the "Human-Robot Interaction Operating System" (HRI/OS). The HRI/OS provides a structured software framework for building human-robot teams, supports a variety of user interfaces, enables humans and robots to engage in task-oriented dialogue, and facilitates integration of robots through an extensible API.

  14. What Research Says: The Cardiovascular System: Children's Conceptions and Misconceptions.

    ERIC Educational Resources Information Center

    Arnaudin, Mary W.; Mintzes, Joel J.

    1986-01-01

    Reports findings of a study on children's perceptions and alternate conceptions about the human circulatory system. Summarizes the responses of fifth and eighth grade students on questions dealing with the heart and blood. Offers examples of hands-on activities and confrontation strategies that address common misconceptions on circulation. (ML)

  15. What Research Says: The Cardiovascular System: Children's Conceptions and Misconceptions.

    ERIC Educational Resources Information Center

    Arnaudin, Mary W.; Mintzes, Joel J.

    1986-01-01

    Reports findings of a study on children's perceptions and alternate conceptions about the human circulatory system. Summarizes the responses of fifth and eighth grade students on questions dealing with the heart and blood. Offers examples of hands-on activities and confrontation strategies that address common misconceptions on circulation. (ML)

  16. Evidence for circulatory benefits of resveratrol in humans.

    PubMed

    Wong, Rachel H X; Coates, Alison M; Buckley, Jonathan D; Howe, Peter R C

    2013-07-01

    Impairments of endothelial function, which can be assessed noninvasively by flow-mediated dilation (FMD) of the brachial artery, contribute to the development of cardiovascular disease. Associations between FMD and cognition suggest a vascular component in the loss of cognitive function. Certain vasoactive nutrients that have been shown to improve FMD may also have the potential to enhance cerebral perfusion and cognition. Preclinical studies show that trans-resveratrol can enhance nitric oxide bioavailability, thereby increasing endothelium-dependent vasodilation. We have now shown that acute administration of resveratrol elicits dose-dependent increases of FMD with greater potency than other vasoactive nutrients and that this benefit is sustained following regular consumption. We describe the potential implications of this vasodilator benefit of resveratrol and its role in enhancing cerebrovascular and cognitive functions. © 2013 New York Academy of Sciences.

  17. Ocular circulatory responses to exhaustive exercise in humans.

    PubMed

    Ikemura, Tsukasa; Hayashi, Naoyuki

    2012-09-01

    It is unclear whether exhaustive dynamic exercise increases ocular blood flow, although we have reported that submaximal exercise increases ocular blood flow. We hypothesized that ocular blood flow decreases at exhaustion, since exhaustion causes hyperventilation, which induces a reduction in PaCO(2). To test this hypothesis, ocular blood flow, blood pressure, and respiratory measurements were made in 12 healthy male subjects during cycle ergometer exercise at 75% of maximal heart rate, until exhaustion. Blood flows in the retinal and choroidal vasculature (RCV), the superior temporal retinal arteriole (STRA), and the superior nasal retinal arteriole (SNRA) were measured with the aid of laser-speckle flowgraphy every 3 min during the exercise. The conductance index (CI) in the ocular vasculature was calculated by dividing the blood flow by the mean arterial pressure (MAP). The mean arterial partial pressure of CO(2) (PaCO(2)) was estimated from tidal volume and end-tidal CO(2) partial pressure. MAP significantly increased from the resting baseline throughout the exercise, while PaCO(2) was significantly decreased at exhaustion and during the recovery period. By 6 min after the onset of exercise, blood flow velocity in the RCV significantly increased by 32 ± 6% (mean ± SD) from the resting baseline value. At exhaustion, blood flow velocity in the RCV did not differ significantly from the resting baseline value, and the STRA blood flow was significantly decreased by 13 ± 4%. The CIs in the RCV, STRA, and SNRA were significantly decreased compared to baseline at exhaustion. These findings suggest that ocular blood flow is increased by submaximal exercise, whereas it is suppressed by the hypocapnia associated with exhaustion.

  18. Addressing Consent Issues in Donation After Circulatory Determination of Death.

    PubMed

    Overby, Kim J; Weinstein, Michael S; Fiester, Autumn

    2015-01-01

    Given the widening gap between the number of individuals on transplant waiting lists and the availability of donated organs, as well as the recent plateau in donations based on neurological criteria (i.e., brain death), there has been a growing interest in expanding donation after circulatory determination of death. While the prevalence of this form of organ donation continues to increase, many thorny ethical issues remain, often creating moral distress in both clinicians and families. In this article, we address one of these issues, namely, the challenges surrounding patient and surrogate informed consent for donation after circulatory determination of death. First we discuss several general concerns regarding consent related to this form of organ donation, and then we address additional issues that are unique to three different patient categories: adult patients with medical decision-making capacity or potential capacity, adult patients who lack capacity, and pediatric patients.

  19. Epigenetic Systems View of Human Development.

    ERIC Educational Resources Information Center

    Gottlieb, Gilbert

    1991-01-01

    Discusses the history of the hierarchical epigenetic systems view as applied to human development and offers examples of its implementation. Notes the agreement by many authors that the multilevel systems view is the right model for developmental psychology in both human and animal studies. (BC)

  20. Toward a New Science of Human Systems.

    ERIC Educational Resources Information Center

    Allen, Peter M.

    1989-01-01

    Contends that social and human sciences are going to be changed by the new ideas and knowledge concerning the evolution of complex systems that is emerging from the natural sciences. Suggests that the work on self-organization theory and synergetic phenomena can serve as the basis for a new science that will allow the study of human systems in…

  1. Development of a Transplantation Risk Index in Patients With Mechanical Circulatory Support: A Decision Support Tool.

    PubMed

    Johnston, Lily E; Grimm, Joshua C; Magruder, J Trent; Shah, Ashish S

    2016-04-01

    The aim of this study was to develop a risk index specific to patients on mechanical circulatory support that accurately predicts 1-year mortality after orthotopic heart transplantation using the United Network for Organ Sharing database. Few clinical tools are available to aid in the decision between continuing long-term device support and performing transplantation in patients bridging with mechanical circulatory support. Using a prospectively collected, open cohort, 6,036 patients receiving mechanical circulatory support who underwent orthotopic heart transplantation between 2000 and 2013 were evaluated and randomly separated into derivation (80%) and validation (20%) groups. Multivariate logistic regression models were constructed using variables that improved the explanatory power of the model, which was determined using multiple methods. Points for a simple additive risk index were apportioned on the basis of relative effect on odds of 1-year mortality. A 75-point scoring system was created from 9 recipient and 4 donor variables. The average score in the validation cohort was 14.4 ± 7.7, and scores ranged from 0 to 57; these values were similar to those in the derivation cohort. Each 1-point increase predicted an 8.3% increase in the odds of 1-year mortality (odds ratio: 1.08; 95% confidence interval: 1.06 to 1.11). Low (0 to 10), intermediate (11 to 20), and high (>20) risk score cohorts were created, with predicted average 1-year mortalities of 8.6%, 12.8%, and 31%, respectively, in the validation cohort. The investigators present a novel, internally cross-validated risk index that accurately predicts mortality in bridge-to-transplantation patients. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  2. Clinical choices for circulatory assist devices.

    PubMed

    Ott, R A; Mills, T C; Eugene, J; Gazzaniga, A B

    1990-01-01

    Approximately 1.0% of open heart surgery patients become unweanable from cardiac bypass during the surgical procedure. In addition, nearly 20% of patients accepted for cardiac transplantation die while waiting for a donor heart. Pulsatile pneumatic ventricular assist devices (VADs) provide a realistic solution to these dilemmas. Currently, there are five manufacturers who are competing for the major market share in the clinical use of these devices. Novacor, Thermetics, Thoratec, Symbion, and Abiomed all have competitive VAD systems. Because no one system is optimal for all patients, the limitations, similarities, and strengths of each system should be known to enhance the patient's outcome when using these devices. Successful use of VAD systems, either as a bridge to transplantation or to ventricular recovery, is best approached by adherence to strict patient selection. Once instituted, VAD management centers on detailed attention to anticoagulation and prompt diagnosis and treatment of various complications.

  3. Circulatory shear flow alters the viability and proliferation of circulating colon cancer cells

    NASA Astrophysics Data System (ADS)

    Fan, Rong; Emery, Travis; Zhang, Yongguo; Xia, Yuxuan; Sun, Jun; Wan, Jiandi

    2016-06-01

    During cancer metastasis, circulating tumor cells constantly experience hemodynamic shear stress in the circulation. Cellular responses to shear stress including cell viability and proliferation thus play critical roles in cancer metastasis. Here, we developed a microfluidic approach to establish a circulatory microenvironment and studied circulating human colon cancer HCT116 cells in response to a variety of magnitude of shear stress and circulating time. Our results showed that cell viability decreased with the increase of circulating time, but increased with the magnitude of wall shear stress. Proliferation of cells survived from circulation could be maintained when physiologically relevant wall shear stresses were applied. High wall shear stress (60.5 dyne/cm2), however, led to decreased cell proliferation at long circulating time (1 h). We further showed that the expression levels of β-catenin and c-myc, proliferation regulators, were significantly enhanced by increasing wall shear stress. The presented study provides a new insight to the roles of circulatory shear stress in cellular responses of circulating tumor cells in a physiologically relevant model, and thus will be of interest for the study of cancer cell mechanosensing and cancer metastasis.

  4. Albumin May Prevent the Morbidity of Paracentesis-Induced Circulatory Dysfunction in Cirrhosis and Refractory Ascites: A Pilot Study.

    PubMed

    Tan, Hiang Keat; James, Paul Damien; Wong, Florence

    2016-10-01

    Large-volume total paracentesis may result in paracentesis-induced circulatory dysfunction, which is associated with poor outcomes. To explore the short- and long-term effects of paracentesis-induced circulatory dysfunction on systemic hemodynamics, renal function and other cirrhosis-related complications in patients with refractory ascites, following subtotal large-volume paracentesis. Patients with cirrhosis and refractory ascites without renal dysfunction had systemic hemodynamics, renal function, and neurohormones (plasma active renin, aldosterone, norepinephrine and angiotensin II) measured pre- and 6 days post-paracentesis. Paracentesis was limited to ≤8 L with 6-8 g of albumin per liter ascites drained. Patients were followed up until transjugular intrahepatic portosystemic shunt insertion, liver transplantation, or death. Paracentesis-induced circulatory dysfunction was defined as >50 % increase in plasma active renin 6 days post-paracentesis. Fifty-seven patients (mean age 59.0 ± 9.4 years) had mean 6.8 ± 1.8 L of ascites removed with 9 ± 3 g of albumin given/L of ascites drained. Patients were followed up for 715 ± 104 days. Twenty-three patients (40.4 %) developed paracentesis-induced circulatory dysfunction with unchanged serum creatinine on day six, despite worsening of hemodynamics (mean arterial pressure 90 ± 10 mmHg at baseline vs. 84 ± 8 mmHg on day six, p < 0.05). Similar hemodynamic changes were observed among patients without paracentesis-induced circulatory dysfunction. There was no significant difference in the long-term renal function or cirrhosis-related complications between the groups. The occurrence of paracentesis-induced circulatory dysfunction, as defined by plasma active renin, may not have a significant short- and long-term impact on renal function or cirrhosis-related complications in patients with refractory ascites who undergo subtotal paracentesis with albumin infusion.

  5. Parking Assistance Systems using Human Guidance

    NASA Astrophysics Data System (ADS)

    Wada, Massaki; Yoon, Kang Sup; Hashimoto, Hideki

    This paper dicusses the problem of parking assistance system development. Firstly, we propose the driver assistance systems general architecture based on path planning and human interface modules. A path generation method based on parking possibility area is developed for the parking assistance systems. The human interface designed for the parking assistance systems is then described. A prototype of the parking assistance systems based on the proposed architecture and approaches have been constructed. Proposed algorithms and implementation solutions in the prototype construction are described. The lane and row parking experimental results obtained with the prototype systems are also shown.

  6. Stupid Tutoring Systems, Intelligent Humans

    ERIC Educational Resources Information Center

    Baker, Ryan S.

    2016-01-01

    The initial vision for intelligent tutoring systems involved powerful, multi-faceted systems that would leverage rich models of students and pedagogies to create complex learning interactions. But the intelligent tutoring systems used at scale today are much simpler. In this article, I present hypotheses on the factors underlying this development,…

  7. Stupid Tutoring Systems, Intelligent Humans

    ERIC Educational Resources Information Center

    Baker, Ryan S.

    2016-01-01

    The initial vision for intelligent tutoring systems involved powerful, multi-faceted systems that would leverage rich models of students and pedagogies to create complex learning interactions. But the intelligent tutoring systems used at scale today are much simpler. In this article, I present hypotheses on the factors underlying this development,…

  8. Human Systems Integration in the Federal Government

    NASA Technical Reports Server (NTRS)

    Jones, Patricia M.; Graves, Gaye L.; Allard, Terry; Blackhurst, Jack; Fitts, David J.; Peters, Sean; Piccione, Dino; Shattuck, Lawrence G.

    2010-01-01

    Human Systems Integration principles and methods can be used to help integrate people, technology, and organizations in an effective and efficient manner. Over the past decade, a wide range of tools, techniques, and technologies have been developed by federal agencies to achieve significant cost and performance benefits. In this discussion, we will explore trends in military human systems integration and learn about the critical role being played by human performance and effectiveness research. We will also examine case studies on the planning and design of future human space flight vehicles, the national air space system and the first nuclear reactors to be built in the United States in over 30 years. And with an eye toward sustaining the discipline s principles and methods, we ll take a look at educating and training the next generation of human systems integration practitioners.

  9. Circulatory response to hyperthermia during acute normovolaemic haemodilution

    NASA Astrophysics Data System (ADS)

    Talwar, Anita; Fahim, M.

    Cats anaesthetized with a mixture of chloralose and urethane were exposed to heat stress in two groups. In the first group (n=10) of control animals, the effect of heat stress on haemodynamic variables was recorded at control haematocrit (HCT) of 42.0+/-1.0%. In a second group, the effect of heat stress was studied after induction of acute normovolaemic haemodilution (HCT of 13.0+/-1.0%). Haemodilution was induced to a maximum of 60% replacement of blood with dextran (mol.wt. 150000). Heat stress was induced by surface heating and core body temperature was raised from 37° C to 42° C. The effect of heat stress and haemodilution on various haemodynamic variables, viz. left ventricular pressure (LVP), left ventricular contractility (LVdP/dtmax), heart rate (HR), cardiac output (CO), arterial blood pressure (ABP), right atrial pressure (RAP), and arterial blood PO2, PCO2 and pH was examined. Haemodilution produced significant (P<0.05) increases in HR and CO but there were no significant (P>0.05) changes in ABP, RAP, LVdP/dtmax and total peripherial resistance (TPR). Hyperthermia caused a significant fall (P<0.05) in TPR. However, the percentage fall in TPR was higher in the control group. On exposure to heat stress, there were significant (P<0.05I increases in HR and CO in both the groups; however, HR and CO values were significantly (P<0.05) higher in the haemodiluted group compared to the control. The latter findings could be due either to the higher basal values of these variables with the fall in HCT or to inefficient cardiovascular regulatory mechanisms. The lack of efficient regulatory control under such severe stress conditions makes the cardiovascular system of anaemic animals more vulnerable to heat stress. In conclusion, the results of the present study showed deleterious effects of heat stress in both the groups. The higher values of HR and CO in the haemodiluted group may be responsible for circulatory failure at low HCT values, indicating a higher risk

  10. Circulatory Shock. Volume 27, Number 4, 1989

    DTIC Science & Technology

    1990-02-01

    19107. Recent reports suggest that circulating endogenous opiates may influence cardiac function. We have investigated the presence of beta -endorphin...cardiac BE to its precursor, beta -lipotropin4 (BLPH), was significantly elevated for AC rats (1.691-0.06 vs 1.1710.06, AC vs So, respectively, pɘ.001). The... glucan ) or saline infusion (control). TABLE. Effect of Macrophage DAYS POST-G/UCAN CHALLENGE 1 2 3 4 5 Activation on systemic host- BLOOD MONONUCLEAR

  11. Do the Spatial Features of an Adjunct Display that Readers Complete while Reading Affect Their Understanding of a Complex System?

    ERIC Educational Resources Information Center

    McCrudden, Matthew T.; McCormick, Montana K.; McTigue, Erin T.

    2011-01-01

    We varied the spatial features of adjunct displays that depicted a complex scientific system (i.e. human circulatory system). University students (n = 47), who were assigned randomly to a display condition before reading, selected relevant information from the text and wrote it (a) next to a list of definitions (list condition), (b) inside boxes…

  12. Do the Spatial Features of an Adjunct Display that Readers Complete while Reading Affect Their Understanding of a Complex System?

    ERIC Educational Resources Information Center

    McCrudden, Matthew T.; McCormick, Montana K.; McTigue, Erin T.

    2011-01-01

    We varied the spatial features of adjunct displays that depicted a complex scientific system (i.e. human circulatory system). University students (n = 47), who were assigned randomly to a display condition before reading, selected relevant information from the text and wrote it (a) next to a list of definitions (list condition), (b) inside boxes…

  13. Human System Drivers for Exploration Missions

    NASA Technical Reports Server (NTRS)

    Kundrot, Craig E.; Steinberg, Susan; Charles, John B.

    2010-01-01

    Evaluation of DRM4 in terms of the human system includes the ability to meet NASA standards, the inclusion of the human system in the design trade space, preparation for future missions and consideration of a robotic precursor mission. Ensuring both the safety and the performance capability of the human system depends upon satisfying NASA Space Flight Human System Standards.1 These standards in turn drive the development of program-specific requirements for Near-earth Object (NEO) missions. In evaluating DRM4 in terms of these human system standards, the currently existing risk models, technologies and biological countermeasures were used. A summary of this evaluation is provided below in a structure that supports a mission architecture planning activities. 1. Unacceptable Level of Risk The duration of the DRM4 mission leads to an unacceptable level of risk for two aspects of human system health: A. The permissible exposure limit for space flight radiation exposure (a human system standard) would be exceeded by DRM4. B. The risk of visual alterations and abnormally high intracranial pressure would be too high. 1

  14. Feedbacks in human-landscape systems

    NASA Astrophysics Data System (ADS)

    Chin, Anne

    2015-04-01

    As human interactions with Earth systems intensify in the "Anthropocene", understanding the complex relationships among human activity, landscape change, and societal responses to those changes is increasingly important. Interdisciplinary research centered on the theme of "feedbacks" in human-landscape systems serves as a promising focus for unraveling these interactions. Deciphering interacting human-landscape feedbacks extends our traditional approach of considering humans as unidirectional drivers of change. Enormous challenges exist, however, in quantifying impact-feedback loops in landscapes with significant human alterations. This paper illustrates an example of human-landscape interactions following a wildfire in Colorado (USA) that elicited feedback responses. After the 2012 Waldo Canyon Fire, concerns for heightened flood potential and debris flows associated with post-fire hydrologic changes prompted local landowners to construct tall fences at the base of a burned watershed. These actions changed the sediment transport regime and promoted further landscape change and human responses in a positive feedback cycle. The interactions ultimately increase flood and sediment hazards, rather than dampening the effects of fire. A simple agent-based model, capable of integrating social and hydro-geomorphological data, demonstrates how such interacting impacts and feedbacks could be simulated. Challenges for fully capturing human-landscape feedback interactions include the identification of diffuse and subtle feedbacks at a range of scales, the availability of data linking impact with response, the identification of multiple thresholds that trigger feedback mechanisms, and the varied metrics and data needed to represent both the physical and human systems. By collaborating with social scientists with expertise in the human causes of landscape change, as well as the human responses to those changes, geoscientists could more fully recognize and anticipate the coupled

  15. NASA Human System Risk Assessment Process

    NASA Technical Reports Server (NTRS)

    Francisco, D.; Romero, E.

    2016-01-01

    NASA utilizes an evidence based system to perform risk assessments for the human system for spaceflight missions. The center of this process is the multi-disciplinary Human System Risk Board (HSRB). The HSRB is chartered from the Chief Health and Medical Officer (OCHMO) at NASA Headquarters. The HSRB reviews all human system risks via an established comprehensive risk and configuration management plan based on a project management approach. The HSRB facilitates the integration of human research (terrestrial and spaceflight), medical operations, occupational surveillance, systems engineering and many other disciplines in a comprehensive review of human system risks. The HSRB considers all factors that influence human risk. These factors include pre-mission considerations such as screening criteria, training, age, sex, and physiological condition. In mission factors such as available countermeasures, mission duration and location and post mission factors such as time to return to baseline (reconditioning), post mission health screening, and available treatments. All of the factors influence the total risk assessment for each human risk. The HSRB performed a comprehensive review of all potential inflight medical conditions and events and over the course of several reviews consolidated the number of human system risks to 30, where the greatest emphasis is placed for investing program dollars for risk mitigation. The HSRB considers all available evidence from human research and, medical operations and occupational surveillance in assessing the risks for appropriate mitigation and future work. All applicable DRMs (low earth orbit for 6 and 12 months, deep space for 30 days and 1 year, a lunar mission for 1 year, and a planetary mission for 3 years) are considered as human system risks are modified by the hazards associated with space flight such as microgravity, exposure to radiation, distance from the earth, isolation and a closed environment. Each risk has a summary

  16. [Effect of noise on circulatory disorders].

    PubMed

    Reinharez, D

    1989-01-01

    The author reports a dramatic case of severe functional and trophic disorders of the lower limbs which proved to be entirely caused by noise. This case led him to study noise and its repercussions on the vascular system: physical characteristics, methods of measurement, epidemiology of this environmental nuisance, general and vascular diseases produced by the traumatic-vibration syndrome, and study of its mechanism of action. He concludes by calling for interdisciplinary action to combine fundamental research, screening and prevention of the disorders caused by noise.

  17. Transfusion-associated circulatory overload in adult, medical emergency patients with perspectives on early warning practice: a single-centre, clinical study.

    PubMed

    Gosmann, Fanny; Nørgaard, Astrid; Rasmussen, Maj-Britt; Rahbek, Charlotte; Seeberg, Jens; Møller, Tom

    2017-01-26

    Transfusion-associated circulatory overload is characterised by acute respiratory distress, tachycardia, increased blood pressure, acute pulmonary oedema and/or evidence of positive fluid balance occurring within 6 hours after transfusion. Transfusion-associated circulatory overload is a serious, underreported reaction, which makes this iatrogenic condition difficult to prevent. We present an audit of patients admitted to a medical emergency unit, aiming to investigate: (i) the incidence of transfusion-associated circulatory overload; and (ii) whether cases were reported to the haemovigilance system. The clinical implications are discussed within the frame of the Early Warning Score. We conducted a retrospective audit of electronic hospital medical records of patients receiving blood transfusion in a single medical emergency unit. Patients were admitted during a 6-month period and data on symptoms and vital signs were extracted from the records. Of 4,353 consecutively admitted patients, 156 patients were transfused with a total of 411 blood components. The audit identified five cases of transfusion-associated circulatory overload (incidence 3.2%) and four cases of transfusion-associated dyspnoea. Vital signs and changes in dyspnoea and blood pressure were registered within the frame of the Early Warning Score, and one case was documented as being transfusion-related in the medical record. No cases were reported to the haemovigilance system. The incidence of transfusion-associated circulatory overload in acute emergency patients was similar to that in other clinical studies. Lack of recognition and reporting was marked, even though changes in vital signs were monitored in the context of the Early Warning Score. This study points to a missing link in the transfusion chain, namely recognising the vital signs of circulatory overload during or shortly after transfusion as being a serious adverse transfusion reaction.

  18. (PCG) Protein Crystal Growth Human Serum Albumin

    NASA Technical Reports Server (NTRS)

    1989-01-01

    (PCG) Protein Crystal Growth Human Serum Albumin. Contributes to many transport and regulatory processes and has multifunctional binding properties which range from various metals, to fatty acids, hormones, and a wide spectrum of therapeutic drugs. The most abundant protein of the circulatory system. It binds and transports an incredible variety of biological and pharmaceutical ligands throughout the blood stream. Principal Investigator on STS-26 was Larry DeLucas.

  19. Modeling of Embedded Human Systems

    DTIC Science & Technology

    2013-07-01

    reduces to solving an initial value HJ PDE. Let the system dynamics be given by ẋ = f(x, u), where f is bounded and Lipschitz continuous in x. Choose the...Sprinkle, “Synthesizing executable simulations from structural models of component- based systems,” Electronic Communications of the European Association

  20. CRESST Human Performance Knowledge Mapping System

    DTIC Science & Technology

    2002-12-01

    team processes and team outcomes. Computers in Human Behavior , 15, 463-494. 0 Herl, H. E. (1995). Construct validation of an approach to modeling...system to measure content understanding. Computers in Human Behavior , 15, 315-334. Johnson, R.F. (2001). Statistical measures of marksmanship (ARI...problem-solving. Computers in Human Behavior , 15, 403-418. West, C. D., Pomeroy, J. R., Park, J. K., Gerstenberger, E. A., & Sandoval, J. (2000

  1. Mechanical circulatory support: balancing bleeding and clotting in high-risk patients.

    PubMed

    Baumann Kreuziger, Lisa; Massicotte, M Patricia

    2015-01-01

    Mechanical circulatory support (MCS) provides a bridge to heart transplant in children and adults with life-threatening heart failure and sustains patients ineligible for transplant. Extracorporeal membrane oxygenation (ECMO) provides temporary support for patients in cardiac or pulmonary failure through external gas exchange and continuous flow of blood. Because the median time to heart transplant exceeds event-free time on ECMO, pulsatile left ventricular assist devices (LVADs) are used to support infants and children. Continuous flow LVADs are preferred in adolescents and adults due to increased pump durability and improved overall survival. The shear stress created by the mechanical pumps cause changes in the hematologic system; acquired von Willebrand syndrome occurs in almost all patients treated with MCS. Despite the improvements in survival, major bleeding occurs in one-third of patients with a LVAD and ischemic stroke and LVAD thrombosis can affect 12% of adults and 29% of children. An antithrombotic strategy to mitigate LVAD bleeding and thrombotic complications has been tested in a randomized trial in children, but intensity of antithrombotic therapy in adults varies widely. Consensus guidelines for antithrombotic therapy during ECMO were created due to significant differences in management across centers. Because of the high risk for both bleeding and thrombotic complications, experts in hemostasis can significantly impact care of patients requiring mechanical circulatory support and are a necessary part of the management team. © 2015 by The American Society of Hematology. All rights reserved.

  2. Recent advances in computational methodology for simulation of mechanical circulatory assist devices

    PubMed Central

    Marsden, Alison L.; Bazilevs, Yuri; Long, Christopher C.; Behr, Marek

    2014-01-01

    Ventricular assist devices (VADs) provide mechanical circulatory support to offload the work of one or both ventricles during heart failure. They are used in the clinical setting as destination therapy, as bridge to transplant, or more recently as bridge to recovery to allow for myocardial remodeling. Recent developments in computational simulation allow for detailed assessment of VAD hemodynamics for device design and optimization for both children and adults. Here, we provide a focused review of the recent literature on finite element methods and optimization for VAD simulations. As VAD designs typically fall into two categories, pulsatile and continuous flow devices, we separately address computational challenges of both types of designs, and the interaction with the circulatory system with three representative case studies. In particular, we focus on recent advancements in finite element methodology that has increased the fidelity of VAD simulations. We outline key challenges, which extend to the incorporation of biological response such as thrombosis and hemolysis, as well as shape optimization methods and challenges in computational methodology. PMID:24449607

  3. The guanylyl cyclase inhibition by MB as vasoplegic circulatory shock therapeutical target.

    PubMed

    Evora, P R B; Viaro, F

    2006-09-01

    There were strong evidences that NO has capital importance in the progressive vasodilatation that associates to the varied circulatory shock forms. The decreased systemic vascular resistance observed in irreversible hemorrhagic (hypovolemic) and septic shock may be due to the excess production of nitric oxide. Other forms of shock associated to anaphylaxis (anaphylactic shock, SIRS) and ischemia reperfusion injury (cardiogenic shock, organ transplants), may involve nitric oxide overproduction. In these situations, the nitric oxide-induced loss of vascular sensitivity to catecholamines and myocardial depression contributes to lethal hypotension. As NO vasodilatation is cyclic GMP-mediated, there were two therapeutical options: a) The unspecific NO synthesis inhibition by L-arginine analogs, iNOS-specific inhibition by corticoids and/or aminoguanidine and; b) Guanylyl cyclase inhibition by MB. As the NO synthesis inhibition is associated to tissue necrosis and adverse hemodynamic effects and its clinical use was associated with high mortality, the second option using MB is safer and more rational. The elaboration of this text was motivated to suggest the guanylyl cyclase inhibition by MB as vasoplegic circulatory shock therapeutical target.

  4. Safety Requirements for Human Rated Space Systems

    NASA Astrophysics Data System (ADS)

    Trujillo, M.; Sgobba, T.

    2010-09-01

    Human rated space systems are those that, to the maximum extent practical, ensure the safety of humans(i.e.: public, ground and crew personnel) from any critical or catastrophic hazards and/or safely recovery from them, ensure that human needs are covered and their capabilities are effectively utilized. The need to define these safety considerations has been the result of previous space accidents and lessons learnt onboard the International Space Station(ISS). In 2003, NASA released programmatic and technical requirements for human rating certification, which were reviewed and updated in 2008. In 2009, ESA launched an activity to identify safety technical requirements for human rated space systems in support of future European crewed space vehicles. Within this framework, ESA has reviewed and evaluated a comprehensive list of documentation, literature and identified a number of proven safety requirements for future crewed vehicles. This paper firstly presents an historical perspective of human spaceflight and European space activities. Secondly, human rating is introduced. Then, it describes the development of ESA safety requirements for human rated space systems and it provides details about its scope, requirements heritage and its applicability for European human spaceflight initiatives.

  5. Systems biology of human atherosclerosis.

    PubMed

    Shalhoub, Joseph; Sikkel, Markus B; Davies, Kerry J; Vorkas, Panagiotis A; Want, Elizabeth J; Davies, Alun H

    2014-01-01

    Systems biology describes a holistic and integrative approach to understand physiology and pathology. The "omic" disciplines include genomics, transcriptomics, proteomics, and metabolic profiling (metabonomics and metabolomics). By adopting a stance, which is opposing (yet complimentary) to conventional research techniques, systems biology offers an overview by assessing the "net" biological effect imposed by a disease or nondisease state. There are a number of different organizational levels to be understood, from DNA to protein, metabolites, cells, organs and organisms, even beyond this to an organism's context. Systems biology relies on the existence of "nodes" and "edges." Nodes are the constituent part of the system being studied (eg, proteins in the proteome), while the edges are the way these constituents interact. In future, it will be increasingly important to collaborate, collating data from multiple studies to improve data sets, making them freely available and undertaking integrative analyses.

  6. Human Systems Integration (HSI) in Acquisition

    DTIC Science & Technology

    2009-08-01

    Cost/Risk Drivers The numbers in the Activities boxes correspond to the numbers In the Inputs and Outputs boxes. Tools: ● CATIA ● HSI Requirements...Technology Development Phase (Inputs) Human Systems Integration Tools: ● IMPRINT ● CATIA ● IPME References: ● DODI 5000.02 & DODD 5000.01 ● DAG ● CJCSI...Human Systems Integration Tools: ● IMPRINT ● CATIA ● IPME Activities for Each Output: 1.0 Incorporate domain considerations into baseline

  7. Complexity of coupled human and natural systems.

    PubMed

    Liu, Jianguo; Dietz, Thomas; Carpenter, Stephen R; Alberti, Marina; Folke, Carl; Moran, Emilio; Pell, Alice N; Deadman, Peter; Kratz, Timothy; Lubchenco, Jane; Ostrom, Elinor; Ouyang, Zhiyun; Provencher, William; Redman, Charles L; Schneider, Stephen H; Taylor, William W

    2007-09-14

    Integrated studies of coupled human and natural systems reveal new and complex patterns and processes not evident when studied by social or natural scientists separately. Synthesis of six case studies from around the world shows that couplings between human and natural systems vary across space, time, and organizational units. They also exhibit nonlinear dynamics with thresholds, reciprocal feedback loops, time lags, resilience, heterogeneity, and surprises. Furthermore, past couplings have legacy effects on present conditions and future possibilities.

  8. A case for human systems neuroscience.

    PubMed

    Gardner, J L

    2015-06-18

    Can the human brain itself serve as a model for a systems neuroscience approach to understanding the human brain? After all, how the brain is able to create the richness and complexity of human behavior is still largely mysterious. What better choice to study that complexity than to study it in humans? However, measurements of brain activity typically need to be made non-invasively which puts severe constraints on what can be learned about the internal workings of the brain. Our approach has been to use a combination of psychophysics in which we can use human behavioral flexibility to make quantitative measurements of behavior and link those through computational models to measurements of cortical activity through magnetic resonance imaging. In particular, we have tested various computational hypotheses about what neural mechanisms could account for behavioral enhancement with spatial attention (Pestilli et al., 2011). Resting both on quantitative measurements and considerations of what is known through animal models, we concluded that weighting of sensory signals by the magnitude of their response is a neural mechanism for efficient selection of sensory signals and consequent improvements in behavioral performance with attention. While animal models have many technical advantages over studying the brain in humans, we believe that human systems neuroscience should endeavor to validate, replicate and extend basic knowledge learned from animal model systems and thus form a bridge to understanding how the brain creates the complex and rich cognitive capacities of humans.

  9. Improvement of microanatomical research by combining corrosion casts with MicroCT and 3D reconstruction, exemplified in the circulatory organs of the woodlouse.

    PubMed

    Wirkner, Christian S; Richter, Stefan

    2004-06-15

    A SkyScan-1072 high-resolution desktop microtomograph was used to visualize the 3D morphology of the circulatory system of Porcellio scaber (Crustacea, Malacostraca, Isopoda) at the micrometer level. Prior to MicroCT investigation, the circulatory system was injected with a fast-hardening resin, permitting a better contrast of the vascular structures that are normally hollow after fixation. Stacks of tomographic images were used to reconstruct the circulatory system three-dimensionally. The spatial resolution achieved by the microtomograph is about 3.5 microm. The technique provides detailed tomographic images of the inner organs and makes precise 3D reconstructions of the circulatory system in arthropods possible. The results were compared with conventional histological data. MicroCT permits a high number of specimens to be screened in a short time, which is essential for the improvement of modern morphological research in a cladistic framework. Histological techniques, however, are still essential for gathering information at the cellular level. Copyright 2004 Wiley-Liss, Inc.

  10. Human Rating the Orion Parachute System

    NASA Technical Reports Server (NTRS)

    Machin, Ricardo A.; Fisher, Timothy E.; Evans, Carol T.; Stewart, Christine E.

    2011-01-01

    Human rating begins with design. Converging on the requirements and identifying the risks as early as possible in the design process is essential. Understanding of the interaction between the recovery system and the spacecraft will in large part dictate the achievable reliability of the final design. Component and complete system full-scale flight testing is critical to assure a realistic evaluation of the performance and reliability of the parachute system. However, because testing is so often difficult and expensive, comprehensive analysis of test results and correlation to accurate modeling completes the human rating process. The National Aeronautics and Space Administration (NASA) Orion program uses parachutes to stabilize and decelerate the Crew Exploration Vehicle (CEV) spacecraft during subsonic flight in order to deliver a safe water landing. This paper describes the approach that CEV Parachute Assembly System (CPAS) will take to human rate the parachute recovery system for the CEV.

  11. Circulatory adaptation to long-term high altitude exposure in Aymaras and Caucasians.

    PubMed

    Stuber, Thomas; Scherrer, Urs

    2010-01-01

    About 30 million people live above 2500 m in the Andean Mountains of South America. Among them are 5.5 million Aymaras, an ethnic group with its own language, living on the altiplano of Bolivia, Peru, and northern Chile at altitudes of up to 4400 m. In this high altitude region traces of human population go back for more than 2000 years with constant evolutionary pressure on its residents for genetic adaptation to high altitude. Aymaras as the assumed direct descendents of the ancient cultures living in this region were the focus of much research interest during the last decades and several distinctive adaptation patterns to life at high altitude have been described in this ethnic group. The aim of this article was to review the physiology and pathophysiology of circulatory adaptation and maladaptation to longtime altitude exposure in Aymaras and Caucasians.

  12. Human systems dynamics: Toward a computational model

    NASA Astrophysics Data System (ADS)

    Eoyang, Glenda H.

    2012-09-01

    A robust and reliable computational model of complex human systems dynamics could support advancements in theory and practice for social systems at all levels, from intrapersonal experience to global politics and economics. Models of human interactions have evolved from traditional, Newtonian systems assumptions, which served a variety of practical and theoretical needs of the past. Another class of models has been inspired and informed by models and methods from nonlinear dynamics, chaos, and complexity science. None of the existing models, however, is able to represent the open, high dimension, and nonlinear self-organizing dynamics of social systems. An effective model will represent interactions at multiple levels to generate emergent patterns of social and political life of individuals and groups. Existing models and modeling methods are considered and assessed against characteristic pattern-forming processes in observed and experienced phenomena of human systems. A conceptual model, CDE Model, based on the conditions for self-organizing in human systems, is explored as an alternative to existing models and methods. While the new model overcomes the limitations of previous models, it also provides an explanatory base and foundation for prospective analysis to inform real-time meaning making and action taking in response to complex conditions in the real world. An invitation is extended to readers to engage in developing a computational model that incorporates the assumptions, meta-variables, and relationships of this open, high dimension, and nonlinear conceptual model of the complex dynamics of human systems.

  13. Recommendations for donation after circulatory death kidney transplantation in Europe.

    PubMed

    van Heurn, L W Ernest; Talbot, David; Nicholson, Michael L; Akhtar, Mohammed Z; Sanchez-Fructuoso, Ana I; Weekers, Laurent; Barrou, Benoit

    2016-07-01

    Donation after circulatory death (DCD) donors provides an invaluable source for kidneys for transplantation. Over the last decade, we have observed a substantial increase in the number of DCD kidneys, particularly within Europe. We provide an overview of risk factors associated with DCD kidney function and survival and formulate recommendations from the sixth international conference on organ donation in Paris, for best-practice guidelines. A systematic review of the literature was performed using Ovid Medline, Embase and Cochrane databases. Topics are discussed, including donor selection, organ procurement, organ preservation, recipient selection and transplant management.

  14. [Cerebral oximetry in pulmonary thromboendarterectomy with circulatory arrest].

    PubMed

    Catalán Escudero, P; González Román, A; Serra Ruiz, C N; Barbero Mielgo, M; García Fernández, J

    2014-02-01

    Pulmonary thromboendarterectomy is an uncommon procedure and should be performed with circulatory arrest. One of the major concerns is the postoperative central neurological injuries. Perioperative brain oxygen monitoring is advisable in this surgical procedure for the early detection of brain hypoperfusion episodes and their intensity as well as any other postoperative episodes that can deteriorate the neurological outcome. Copyright © 2012 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  15. An advanced computational bioheat transfer model for a human body with an embedded systemic circulation.

    PubMed

    Coccarelli, Alberto; Boileau, Etienne; Parthimos, Dimitris; Nithiarasu, Perumal

    2016-10-01

    In the present work, an elaborate one-dimensional thermofluid model for a human body is presented. By contrast to the existing pure conduction-/perfusion-based models, the proposed methodology couples the arterial fluid dynamics of a human body with a multi-segmental bioheat model of surrounding solid tissues. In the present configuration, arterial flow is included through a network of elastic vessels. More than a dozen solid segments are employed to represent the heat conduction in the surrounding tissues, and each segment is constituted by a multilayered circular cylinder. Such multi-layers allow flexible delineation of the geometry and incorporation of properties of different tissue types. The coupling of solid tissue and fluid models requires subdivision of the arterial circulation into large and small arteries. The heat exchange between tissues and arterial wall occurs by convection in large vessels and by perfusion in small arteries. The core region, including the heart, provides the inlet conditions for the fluid equations. In the proposed model, shivering, sweating, and perfusion changes constitute the basis of the thermoregulatory system. The equations governing flow and heat transfer in the circulatory system are solved using a locally conservative Galerkin approach, and the heat conduction in the surrounding tissues is solved using a standard implicit backward Euler method. To investigate the effectiveness of the proposed model, temperature field evolutions are monitored at different points of the arterial tree and in the surrounding tissue layers. To study the differences due to flow-induced convection effects on thermal balance, the results of the current model are compared against those of the widely used modelling methodologies. The results show that the convection significantly influences the temperature distribution of the solid tissues in the vicinity of the arteries. Thus, the inner convection has a more predominant role in the human body heat

  16. A non-invasive technique for the evaluation of peripheral circulatory functions in female subjects with Raynaud’s phenomenon

    PubMed Central

    MIRBOD, Seyed Mohammad; SUGIURA, Haruo

    2017-01-01

    Japanese women now account for 43 percent of the labor force. A number of them are involved in construction, agricultural and forestry jobs. The aim of this study was to establish a non-invasive technique for the evaluation of peripheral circulatory functions in women with Raynaud’s phenomenon (RP) and introduce a specific method for the assessment of vascular disturbances in females exposed to hand-transmitted vibration. The subjects of this study were 10 women with primary RP, 7 women with progressive systemic sclerosis (PSS) secondary to RP, and 17 females who were included as the control group. The evaluation of peripheral circulatory functions in all subjects was based on the values of finger blood flow (FBF) and finger skin temperature (FST) measured before, during and following a 5-min recovery period after the hand was immersed in cold water (5°C, 1 min). The measured values of FBF and FST of the primary RP group before and after the immersion test were significantly (p<0.01) lower compared to those of the control group. The technique applied in this study could be used as a non-invasive and tolerable technique to determine the digital circulatory functions in female subjects with RP. PMID:28321017

  17. System for Odorless Disposal of Human Waste

    NASA Technical Reports Server (NTRS)

    Jennings, Dave; Lewis, Tod

    1987-01-01

    Conceptual system provides clean, hygienic storage. Disposal system stores human wastes compactly. Releases no odor or bacteria and requires no dangerous chemicals or unpleasant handling. Stabilizes waste by natural process of biodegradation in which microbial activity eventually ceases and ordors and bacteria reduced to easily contained levels. Simple and reliable and needs little maintenance.

  18. System for Odorless Disposal of Human Waste

    NASA Technical Reports Server (NTRS)

    Jennings, Dave; Lewis, Tod

    1987-01-01

    Conceptual system provides clean, hygienic storage. Disposal system stores human wastes compactly. Releases no odor or bacteria and requires no dangerous chemicals or unpleasant handling. Stabilizes waste by natural process of biodegradation in which microbial activity eventually ceases and ordors and bacteria reduced to easily contained levels. Simple and reliable and needs little maintenance.

  19. Policy Interactions in Human-Landscape Systems

    NASA Astrophysics Data System (ADS)

    Gerlak, Andrea K.

    2014-01-01

    Given the heightened pace and extent of human interactions with landscapes, there is increasing recognition of the interdependence of hydrogeomorphological, ecological, and human systems in understanding human-landscape interactions. There is also widespread agreement for greater integration across disciplinary boundaries to generate new knowledge urgently needed for theory building to understand, predict, and respond to rapidly changing human-landscape systems. The development of new conceptual frameworks, methods, tools, and collaborations linking across the natural and social sciences are key elements to such integration. In an effort to contribute to a broader conceptual framework for human-landscape systems, this paper describes how environmental policy research has contributed to four integrative themes—thresholds and tipping points; spatial scales and boundaries; feedback loops; and time scales and lags—developed by participants in an NSF-sponsored interdisciplinary workshop. As a broad and heterogeneous body of literature, environmental policy research reflects a diversity of methodological and theoretical approaches around institutions, actors, processes, and ideas. We integrate across multiple subfields and research programs to help identify complementarities in research that may support future interdisciplinary collaborative work. We conclude with a discussion of future research questions to help advance greater interdisciplinary research around human-landscape systems.

  20. [Human resources for local health systems].

    PubMed

    Linger, C

    1989-01-01

    The economic and social crises affecting Latin America have had a profound social and political effect on its structures. This paper analyzes this impact from 2 perspectives: 1) the impact on the apparatus of the state, in particular on its health infra-structures; and 2) the direction of the democratic process in the continent and the participatory processes of civil societies. The institutionalization of the Local Health Systems (SILOS) is an effort to analyze the problem from within the health sector and propose solutions. This paper discusses the issues of human resource development in health systems; training in human resource development and human resource development in local health care systems. There are 3 strategies used to change health systems: 1) The judicial-political system: The state's apparatus 2) The political-administrative system: the national health care system; and 3) the political-operative system: local health care systems. To assure implementation of SILOS there are 4 steps to be followed: 1) create political conditions that allow the transformation and development of local health systems; 2) development of high-level institutional and political initiatives to develop health care networks; 3) offer key players institutional space and social action to develop the SILOS process; 4) rapidly develop SILOS in regions to assure its integration with other development efforts. The labor force in the health sector and organized communities play critical roles in proposing and institutionalizing health programs.

  1. The New Era of the Lymphatic System: No Longer Secondary to the Blood Vascular System

    PubMed Central

    Choi, Inho; Lee, Sunju; Hong, Young-Kwon

    2012-01-01

    The blood and lymphatic systems are the two major circulatory systems in our body. Although the blood system has been studied extensively, the lymphatic system has received much less scientific and medical attention because of its elusive morphology and mysterious pathophysiology. However, a series of landmark discoveries made in the past decade has begun to change the previous misconception of the lymphatic system to be secondary to the more essential blood vascular system. In this article, we review the current understanding of the development and pathology of the lymphatic system. We hope to convince readers that the lymphatic system is no less essential than the blood circulatory system for human health and well-being. PMID:22474611

  2. Human Systems Integration (HSI) Practitioner's Guide

    NASA Technical Reports Server (NTRS)

    Zumbado, Jennifer Rochlis

    2015-01-01

    The NASA/SP-2015-3709, Human Systems Integration (HSI) Practitioner's Guide, also known as the "HSIPG," provides a tool for implementing HSI activities within the NASA systems engineering framework. The HSIPG is written to aid the HSI practitioner engaged in a program or project (P/P), and serves as a knowledge base to allow the practitioner to step into an HSI lead or team member role for NASA missions. Additionally, this HSIPG is written to address the role of HSI in the P/P management and systems engineering communities and aid their understanding of the value added by incorporating good HSI practices into their programs and projects. Through helping to build a community of knowledgeable HSI practitioners, this document also hopes to build advocacy across the Agency for establishing strong, consistent HSI policies and practices. Human Systems Integration (HSI) has been successfully adopted (and adapted) by several federal agencies-most notably the U.S. Department of Defense (DoD) and the Nuclear Regulatory Commission (NRC)-as a methodology for reducing system life cycle costs (LCCs). These cost savings manifest themselves due to reductions in required numbers of personnel, the practice of human-centered design, decreased reliance on specialized skills for operations, shortened training time, efficient logistics and maintenance, and fewer safety-related risks and mishaps due to unintended human/system interactions. The HSI process for NASA establishes how cost savings and mission success can be realized through systems engineering. Every program or project has unique attributes. This HSIPG is not intended to provide one-size-fits-all recommendations for HSI implementation. Rather, HSI processes should be tailored to the size, scope, and goals of individual situations. The instructions and processes identified here are best used as a starting point for implementing human-centered system concepts and designs across programs and projects of varying types, including

  3. The French airbridge for circulatory support in the Carribean†

    PubMed Central

    Lebreton, Guillaume; Sanchez, Bruno; Hennequin, Jean-Luc; Resière, Dabor; Hommel, Didier; Léonard, Christian; Mehdaoui, Hossein; Roques, François

    2012-01-01

    OBJECTIVES We report the assessment and the activities for the first year of our airborne circulatory support mobile unit (CSMU) in the French Caribbean. METHODS From January 2010 to June 2011, 12 patients (mean age = 35.7 years; range: 15–62 years; sex ratio = 1:1) were attended outside Martinique by our CSMU and transferred to our unit by air. RESULTS Eight patients had acute respiratory distress syndrome and were assisted by veno-venous extra corporeal membrane oxygenation (ECMO) four had refractory cardiogenic shock, assisted by extra corporeal life support (ECLS). The average air transfer distance for patients was 912 km (range: 198–1585 km). The average flying time was 124 min (range: 45–255 min). The aircraft used were heliciopter, military transport or private jet. The setting-up of assistance devices and transfer of patients was uneventful. One patient subsequently benefited from heart transplantation after long-term circulatory support. One patient died under ECMO support after 51 days of assistance and another died on the 60th day after withdrawal of ECLS. CONCLUSIONS CSMUs can be very efficient in providing support to patients in refractory shock, when remote from a cardiac surgery centre. The airborne transfer of patients on ECMO/ECLS can be achieved safely, even over long distances. PMID:22659268

  4. Visual-evoked potentials in patients with brain circulatory problems.

    PubMed

    Pojda-Wilczek, Dorota

    2015-04-01

    The aim of this study was to find out if local brain circulatory problems may influence visual-evoked potentials (VEP). Thirty-eight patients were divided into the following groups: (I) those with hemianopsia or quadrantanopsia and hemiparesis after brain stroke; (II) those with hemianopsia or quadrantanopsia without paresis after brain stroke; and (III) those with amaurosis fugax. The control group consisted of 38 patients. The VEP pattern (PVEP) and flash VEP (FVEP) were examined monocularly using two electrodes placed at O1 and O2. Latency and amplitude of the N75, P100 and N2, P2 waves were measured. The Newman-Keuls test was used for statistical analysis. In PVEP, no differences between the groups were observed. In FVEP, the mean P2 latency was significantly longer in group I than in group III, and the P2 amplitude was significantly lower in all examined groups when compared with the control group. PVEP and FVEP revealed differences in P latency over 3 ms between brain hemispheres and differences in P amplitude over 30% in all examined groups. In the control group, there were no differences in latency between brain hemispheres and only a small difference in amplitude. Local brain circulatory problems that may lead to brain ischemia cause differences in VEP amplitude and latency between brain hemispheres. Changes in VEPs observed in patients with amaurosis fugax may be considered the result of recurrent brain ischemia.

  5. Ethical controversies in organ donation after circulatory death.

    PubMed

    2013-05-01

    The persistent mismatch between the supply of and need for transplantable organs has led to efforts to increase the supply, including controlled donation after circulatory death (DCD). Controlled DCD involves organ recovery after the planned withdrawal of life-sustaining treatment and the declaration of death according to the cardiorespiratory criteria. Two central ethical issues in DCD are when organ recovery can begin and how to manage conflicts of interests. The "dead donor rule" should be maintained, and donors in cases of DCD should only be declared dead after the permanent cessation of circulatory function. Permanence is generally established by a 2- to 5-minute waiting period. Given ongoing controversy over whether the cessation must also be irreversible, physicians should not be required to participate in DCD. Because the preparation for organ recovery in DCD begins before the declaration of death, there are potential conflicts between the donor's and recipient's interests. These conflicts can be managed in a variety of ways, including informed consent and separating the various participants' roles. For example, informed consent should be sought for premortem interventions to improve organ viability, and organ procurement organization personnel and members of the transplant team should not be involved in the discontinuation of life-sustaining treatment or the declaration of death. It is also important to emphasize that potential donors in cases of DCD should receive integrated interdisciplinary palliative care, including sedation and analgesia.

  6. Development of an implantable centrifugal blood pump for circulatory assist.

    PubMed

    Wakisaka, Y; Taenaka, Y; Chikanari, K; Okuzono, Y; Endo, S; Takano, H

    1997-01-01

    An implantable centrifugal pump (ICP) for prolonged circulatory assist has been developed, at 320 ml and 830 g. A central balancing hole was made in its impeller for better antithrombogenicity. Waterproofing and histocompatibility were supported by a silicone seal and a casing made of titanium and acrylic resin. Overall efficiency was 30% and normalized index of homolysis was 0.003 mg/dl, the same value as the BP-80, at a flow rate of 5 L/min and a head of 100 mmHg. Antithrombogenicity and hemolytic properties of the ICP were investigated in paracorporeal implantation in three goats (61-71 kg). Exothermicity, anatomic fit, and water tightness of the ICP were evaluated in intrathoracic implantation in an adult goat (66 kg). The ICP could run paracorporeally for 50, 200, and 381 days. There was no thrombus in the ICP after 381 days' pumping, and the ICP could run in the chest cavity for 40 days. The temperature of the motor rose 1.8 +/- 0.3 degrees C from that of the pleura. Moisture content of the seal remained normal. The ICP was completely covered with smooth fibrous tissue. Although a small area of atelectasis was found in the lingula, neither lung adhesion nor necrosis of the chest wall was observed. The ICP has satisfactory antithrombogenicity, hemolytic property, water tightness, anatomic fit, and exothermicity for use as an implantable circulatory assist device.

  7. Development of Human System Integration at NASA

    NASA Technical Reports Server (NTRS)

    Whitmore, Mihriban; McGuire, Kerry; Thompson, Shelby; Vos, Gordon

    2012-01-01

    Human Systems Integration seeks to design systems around the capabilities and limitations of the humans which use and interact with the system, ensuring greater efficiency of use, reduced error rates, and less rework in the design, manufacturing and operational deployment of hardware and software. One of the primary goals of HSI is to get the human factors practitioner involved early in the design process. In doing so, the aim is to reduce future budget costs and resources in redesign and training. By the preliminary design phase of a project nearly 80% of the total cost of the project is locked in. Potential design changes recommended by evaluations past this point will have little effect due to lack of funding or a huge cost in terms of resources to make changes. Three key concepts define an effective HSI program. First, systems are comprised of hardware, software, and the human, all of which operate within an environment. Too often, engineers and developers fail to consider the human capacity or requirements as part of the system. This leads to poor task allocation within the system. To promote ideal task allocation, it is critical that the human element be considered early in system development. Poor design, or designs that do not adequately consider the human component, could negatively affect physical or mental performance, as well as, social behavior. Second, successful HSI depends upon integration and collaboration of all the domains that represent acquisition efforts. Too often, these domains exist as independent disciplines due to the location of expertise within the service structure. Proper implementation of HSI through participation would help to integrate these domains and disciplines to leverage and apply their interdependencies to attain an optimal design. Via this process domain interests can be integrated to perform effective HSI through trade-offs and collaboration. This provides a common basis upon which to make knowledgeable decisions. Finally

  8. Sex differences in the human visual system.

    PubMed

    Vanston, John E; Strother, Lars

    2017-01-02

    This Mini-Review summarizes a wide range of sex differences in the human visual system, with a primary focus on sex differences in visual perception and its neural basis. We highlight sex differences in both basic and high-level visual processing, with evidence from behavioral, neurophysiological, and neuroimaging studies. We argue that sex differences in human visual processing, no matter how small or subtle, support the view that females and males truly see the world differently. We acknowledge some of the controversy regarding sex differences in human vision and propose that such controversy should be interpreted as a source of motivation for continued efforts to assess the validity and reliability of published sex differences and for continued research on sex differences in human vision and the nervous system in general. © 2016 Wiley Periodicals, Inc.

  9. Human System Risk Management for Space Flight

    NASA Technical Reports Server (NTRS)

    Davis, Jeffrey

    2015-01-01

    This brief abstract reviews the development of the current day approach to human system risk management for space flight and the development of the critical components of this process over the past few years. The human system risk management process now provides a comprehensive assessment of each human system risk by design reference mission (DRM) and is evaluated not only for mission success but also for long-term health impacts for the astronauts. The discipline of bioastronautics is the study of the biological and medical effects of space flight on humans. In 1997, the Space Life Sciences Directorate (SLSD) initiated the Bioastronautics Roadmap (Roadmap) as the "Critical Path Roadmap", and in 1998 participation in the roadmap was expanded to include the National Space Biomedical Research Institute (NSBRI) and the external community. A total of 55 risks and 250 questions were identified and prioritized and in 2000, the Roadmap was base-lined and put under configuration control. The Roadmap took into account several major advisory committee reviews including the Institute of Medicine (IOM) "Safe Passage: Astronaut care for Exploration Missions", 2001. Subsequently, three collaborating organizations at NASA HQ (Chief Health and Medical Officer, Office of Space Flight and Office of Biological & Physical Research), published the Bioastronautics Strategy in 2003, that identified the human as a "critical subsystem of space flight" and noted that "tolerance limits and safe operating bands must be established" to enable human space flight. These offices also requested a review by the IOM of the Roadmap and that review was published in October 2005 as "A Risk Reduction Strategy for Human Exploration of Space: A Review of NASA's Bioastronautics Roadmap", that noted several strengths and weaknesses of the Roadmap and made several recommendations. In parallel with the development of the Roadmap, the Office of the Chief Health and Medical Officer (OCHMO) began a process in

  10. Human performance modeling for system of systems analytics.

    SciTech Connect

    Dixon, Kevin R.; Lawton, Craig R.; Basilico, Justin Derrick; Longsine, Dennis E.; Forsythe, James Chris; Gauthier, John Henry; Le, Hai D.

    2008-10-01

    A Laboratory-Directed Research and Development project was initiated in 2005 to investigate Human Performance Modeling in a System of Systems analytic environment. SAND2006-6569 and SAND2006-7911 document interim results from this effort; this report documents the final results. The problem is difficult because of the number of humans involved in a System of Systems environment and the generally poorly defined nature of the tasks that each human must perform. A two-pronged strategy was followed: one prong was to develop human models using a probability-based method similar to that first developed for relatively well-understood probability based performance modeling; another prong was to investigate more state-of-art human cognition models. The probability-based modeling resulted in a comprehensive addition of human-modeling capability to the existing SoSAT computer program. The cognitive modeling resulted in an increased understanding of what is necessary to incorporate cognition-based models to a System of Systems analytic environment.

  11. Mechanical ventilation and thoracic artificial lung assistance during mechanical circulatory support with PUCA pump: in silico study.

    PubMed

    De Lazzari, Claudio; Genuini, Igino; Quatember, Bernhard; Fedele, Francesco

    2014-02-01

    Patients assisted with left ventricular assist device (LVAD) may require prolonged mechanical ventilatory assistance secondary to postoperative respiratory failure. The goal of this work is the study of the interdependent effects LVAD like pulsatile catheter (PUCA) pump and mechanical ventilatory support or thoracic artificial lung (TAL), by the hemodynamic point of view, using a numerical simulator of the human cardiovascular system. In the simulator, different circulatory sections are described using lumped parameter models. Lumped parameter models have been designed to describe the hydrodynamic behavior of both PUCA pump and thoracic artificial lung. Ventricular behavior atrial and septum functions were reproduced using variable elastance model. Starting from simulated pathological conditions we studied the effects produced on some hemodynamic variables by simultaneous PUCA pump, thoracic artificial lung or mechanical ventilation assistance. Thoracic artificial lung was applied in parallel or in hybrid mode. The effects of mechanical ventilation have been simulated by changing mean intrathoracic pressure value from -4 mmHg to +5 mmHg. The hemodynamic variables observed during the simulations, in different assisted conditions, were: left and right ventricular end systolic (diastolic) volume, systolic/diastolic aortic pressure, mean pulmonary arterial pressure, left and right mean atrial pressure, mean systemic venous pressure and the total blood flow. Results show that the application of PUCA (without mechanical ventilatory assistance) increases the total blood flow, reduces the left ventricular end systolic volume and increases the diastolic aortic pressure. Parallel TAL assistance increases the right ventricular end diastolic (systolic) volume reduction both when PUCA is switched "ON" and both when PUCA is switched "OFF". By switching "OFF" the PUCA pump, it seems that parallel thoracic artificial lung assistance produces a greater cardiac output (respect to

  12. Human factors in modern traffic systems.

    PubMed

    Noy, Y I

    1997-10-01

    Traffic systems are undergoing enormous change with the advent of Intelligent Transport Systems (ITS). Although productivity and quality of mobility are emerging interests, safety remains the predominant preoccupation of ITS human factors. It should be evident that while intelligent technologies may have the potential to improve traffic safety, they also have the potential to adversely affect it. Ultimately, the effect on safety depends on the specific technologies that are invoked and the manner in which they are incorporated within the vehicle as well as within the larger road transportation system. Current automotive developments can be characterized as technology-centred solutions rather than user-centred solutions. Greater effort must be directed at understanding and accommodating the human element in the road transportation system in order that future transportation objectives can be achieved. There is a need to expand the scope of traditional human factors to include macro-level effects as well as to place greater emphasis on understanding human interactions with other elements of the system. There is also increasing recognition of the urgent need for systematic procedures and criteria for testing the safety of ITS prior to large-scale market penetration.

  13. Respiratory and Circulatory Systems, Science (Experimental): 5363.04.

    ERIC Educational Resources Information Center

    Weiss, Alan; And Others

    This biology course is especially recommended for students interested in a vocation in nursing, medical technology, dental hygiene or other para-medical areas. In part, it is considered a second course in biology. The course includes an intensive in-depth study of the respiratory structures, nerve and chemical control of breathing, gas exchange,…

  14. Influence of psoriasis on circulatory system function assessed in echocardiography.

    PubMed

    Milaniuk, Sylwia; Pietrzak, Aldona; Mosiewicz, Barbara; Mosiewicz, Jerzy; Reich, Kristian

    2015-12-01

    Psoriasis vulgaris is a chronic disease with a multifactorial pathogenesis. It affects about 2-4 % of the population all over the world. In course of psoriatic arthritis, joints' damages are observed. In patients with psoriasis vulgaris and psoriatic arthritis, there is increased morbidity and mortality caused by cardiovascular diseases observed. The aim of the study is to analyze the echocardiography of patients with psoriasis vulgaris and psoriatic arthritis on the basis of the literature available in PubMed database. Abnormalities found in echocardiography of patients with psoriasis include valvular defects (40.7 % of the patients), left ventricle diastolic dysfunction (27.8 %), and left ventricle hypertrophy (11.1 %). Left ventricle's systolic disorders, increased aorta stiffness index and increased pulmonary artery blood pressure were also observed in this group of patients.

  15. Outcomes following implantation of mechanical circulatory support in adults with congenital heart disease: An analysis of the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS).

    PubMed

    VanderPluym, Christina J; Cedars, Ari; Eghtesady, Pirooz; Maxwell, Bryan G; Gelow, Jill M; Burchill, Luke J; Maltais, Simon; Koehl, Devin A; Cantor, Ryan S; Blume, Elizabeth D

    2017-03-07

    Adults with congenital heart disease represent an expanding and unique population of patients with heart failure (HF) in whom the use of mechanical circulatory support (MCS) has not been characterized. We sought to describe overall use, patient characteristics, and outcomes of MCS in adult congenital heart disease (ACHD). All patients entered into the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) between June 23, 2006, and December 31, 2015, were included. Patients with ACHD were identified using pre-operative data and stratified by ventricular morphology. Mortality was compared between ACHD and non-ACHD patients, and multivariate analysis was performed to identify predictors of death after device implantation. Of 16,182 patients, 126 with ACHD stratified as follows: systemic morphologic left ventricle (n = 63), systemic morphologic right ventricle (n = 45), and single ventricle (n = 17). ACHD patients were younger (42 years ± 14 vs 56 years ± 13; p < 0.0001) and were more likely to undergo device implantation as bridge to transplant (45% vs 29%; p < 0.0001). A higher proportion of ACHD patients had biventricular assist device (BiVAD)/total artificial heart (TAH) support compared with non-ACHD patients (21% vs 7%; p < 0.0001). More ACHD patients on BiVAD/TAH support were INTERMACS profile 1 compared with patients on systemic left ventricular assist device (LVAD) support (35% vs 15%; p = 0.002). ACHD and non-ACHD patients with LVADs had similar survival; survival was worse for patients on BIVAD/TAH support. BiVAD/TAH support was the only variable independently associated with mortality (early phase hazard ratio 4.4; 95% confidence interval, 1.8-11.1; p = 0.001). For ACHD patients receiving MCS, ventricular morphology was not associated with mortality. ACHD patients with LVADs have survival similar to non-ACHD patients. Mortality is higher for patients requiring BiVAD/TAH support, potentially owing to higher INTERMACS profile. These

  16. Human Systems Engineering and Program Success - A Retrospective Content Analysis

    DTIC Science & Technology

    2016-01-01

    costs related to human performance (e.g., Human Total Ownership Cost) early in the life cycle will lead to schedule overruns, diminished system...FIGURE 1. VENN DIAGRAM OF INTERRELATIONSHIPS AMONG WEAPON SYSTEMS, HSI, AND LIFE-CYCLE COST, PERFORMANCE , AND SCHEDULE Weapon Systems Human ...MANPRINT) Human Factors Engineering fatigue, human , people, perform , performance , performed , performing , performs , situational awareness, troops

  17. Morphogenesis of the human excretory lacrimal system

    PubMed Central

    de la Cuadra-Blanco, C; Peces-Peña, M D; Jáñez-Escalada, L; Mérida-Velasco, J R

    2006-01-01

    The aim of this study was to determine the principal developmental stages in the formation of the excretory lacrimal system in humans and to establish its morphogenetic period. The study was performed using light microscopy on serial sections of 51 human specimens: 33 embryos and 18 fetuses ranging from 8 to 137 mm crown–rump length (CR; 5–16 weeks of development). Three stages were identified in the morphogenesis of the excretory lacrimal system: (1) the formative stage of the lacrimal lamina (Carnegie stages 16–18); (2) the formative stage of the lacrimal cord (Carnegie stages 19–23); and (3) the maturative stage of the excretory lacrimal system, from the 9th week of development onward. A three-dimensional reconstruction of the excretory lacrimal system was performed from serial sections of an embryo at the end of the embryonic period (27 mm CR). PMID:16879594

  18. Human Transportation System (HTS) study: Executive summary

    NASA Technical Reports Server (NTRS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-01-01

    Work completed under the Human Transportation System Study is summarized. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems as well as proposed systems to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are the following: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  19. Deployment of human-machine dialogue systems.

    PubMed Central

    Roe, D B

    1995-01-01

    The deployment of systems for human-to-machine communication by voice requires overcoming a variety of obstacles that affect the speech-processing technologies. Problems encountered in the field might include variation in speaking style, acoustic noise, ambiguity of language, or confusion on the part of the speaker. The diversity of these practical problems encountered in the "real world" leads to the perceived gap between laboratory and "real-world" performance. To answer the question "What applications can speech technology support today?" the concept of the "degree of difficulty" of an application is introduced. The degree of difficulty depends not only on the demands placed on the speech recognition and speech synthesis technologies but also on the expectations of the user of the system. Experience has shown that deployment of effective speech communication systems requires an iterative process. This paper discusses general deployment principles, which are illustrated by several examples of human-machine communication systems. Images Fig. 1 PMID:7479719

  20. Human Transportation System (HTS) study, volume 1

    NASA Technical Reports Server (NTRS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-01-01

    Work completed under the Human Transportation System Study is summarized. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems as well as proposed systems to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are the following: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  1. Transient Decrease in Circulatory Testosterone and Homocysteine Precedes the Development of Metabolic Syndrome Features in Fructose-Fed Sprague Dawley Rats

    PubMed Central

    Sakamuri, Anil; Pitla, Sujatha; Putcha, Uday Kumar; Jayapal, Sugeedha; Pothana, Sailaja; Vadakattu, Sai Santosh

    2016-01-01

    Background. Increased fructose consumption is linked to the development of metabolic syndrome (MS). Here we investigated the time course of development of MS features in high-fructose-fed Sprague Dawley rats along with circulatory testosterone and homocysteine levels. Methods. Rats were divided into control and experimental groups and fed with diets containing 54.5% starch and fructose, respectively, for 4, 12, and 24 weeks. Plasma testosterone and homocysteine levels were measured along with insulin, glucose, and lipids. Body composition, insulin resistance, and hepatic lipids were measured. Results. Increase in hepatic triglyceride content was first observed in metabolic disturbance followed by hypertriglyceridemia and systemic insulin resistance in fructose-fed rats. Hepatic lipids were increased in time-dependent manner by fructose-feeding starting from 4 weeks, but circulatory triglyceride levels were increased after 12 weeks. Fasting insulin and Homeostatis Model Assessment of Insulin Resistance (HOMA-IR) were increased after 12 weeks of fructose-feeding. Decreased visceral adiposity, circulatory testosterone, and homocysteine levels were observed after 4 weeks of fructose-feeding, which were normalized at 12 and 24 weeks. Conclusions. We conclude that transient decrease in circulatory testosterone and homocysteine levels and increased hepatic triglyceride content are the earliest metabolic disturbances that preceded hypertriglyceridemia and insulin resistance in fructose-fed SD rats. PMID:27818793

  2. Interactions between human behaviour and ecological systems

    PubMed Central

    Milner-Gulland, E. J.

    2012-01-01

    Research on the interactions between human behaviour and ecological systems tends to focus on the direct effects of human activities on ecosystems, such as biodiversity loss. There is also increasing research effort directed towards ecosystem services. However, interventions to control people's use of the environment alter the incentives that natural resource users face, and therefore their decisions about resource use. The indirect effects of conservation interventions on biodiversity, modulated through human decision-making, are poorly studied but are likely to be significant and potentially counterintuitive. This is particularly so where people are dependent on multiple natural resources for their livelihoods, when both poverty and biodiversity loss are acute. An inter-disciplinary approach is required to quantify these interactions, with an understanding of human decision-making at its core; otherwise, predictions about the impacts of conservation policies may be highly misleading. PMID:22144389

  3. EXTRACORPOREAL MEMBRANE OXYGENATION vs. COUNTERPULSATILE, PULSATILE, AND CONTINUOUS LEFT VENTRICULAR UNLOADING FOR PEDIATRIC MECHANICAL CIRCULATORY SUPPORT

    PubMed Central

    Bartoli, Carlo R.; Koenig, Steven C.; Ionan, Constantine; Gillars, Kevin J.; Mitchell, Mike E.; Austin, Erle H.; Gray, Laman A.; Pantalos, George M.

    2014-01-01

    OBJECTIVE Despite progress with adult ventricular assist devices (VADs), limited options exist to support pediatric patients with life-threatening heart disease. Extracorporeal membrane oxygenation (ECMO) remains the clinical standard. To characterize (patho)physiologic responses to different modes of mechanical unloading of the failing pediatric heart, ECMO was compared to either intraaortic balloon pump (IABP), pulsatile-flow (PF)VAD, or continuous-flow (CF)VAD support in a pediatric heart failure model. DESIGN Experimental. SETTING Large animal laboratory operating room. SUBJECTS Yorkshire piglets (n=47, 11.7±2.6 kg). INTERVENTIONS In piglets with coronary ligation-induced cardiac dysfunction, mechanical circulatory support devices were implanted and studied during maximum support. MEASUREMENTS and MAIN RESULTS Left ventricular, right ventricular, coronary, carotid, systemic arterial, and pulmonary arterial hemodynamics were measured with pressure and flow transducers. Myocardial oxygen consumption and total-body oxygen consumption (VO2) were calculated from arterial, venous, and coronary sinus blood sampling. Blood flow was measured in 17 organs with microspheres. Paired student t-tests compared baseline and heart failure conditions. One-way repeated-measures ANOVA compared heart failure, device support mode(s), and ECMO. Statistically significant (p<0.05) findings included: 1) improved left ventricular blood supply/demand ratio during PFVAD, CFVAD, and ECMO but not IABP support, 2) improved global myocardial blood supply/demand ratio during PFVAD, and CFVAD but not IABP or ECMO support, and 3) diminished pulsatility during ECMO and CFVAD but not IABP and PFVAD support. A profile of systems-based responses was established for each type of support. CONCLUSIONS Each type of pediatric VAD provided hemodynamic support by unloading the heart with a different mechanism that created a unique profile of physiological changes. These data contribute novel, clinically

  4. Does uranium induce circulatory diseases? First results from a French cohort of uranium workers.

    PubMed

    Guseva Canu, Irina; Garsi, Jerome-Philippe; Caër-Lorho, Sylvaine; Jacob, Sophie; Collomb, Philippe; Acker, Alain; Laurier, Dominique

    2012-06-01

    Increased risk of circulatory system diseases (CSDs) was observed in nuclear workers handling uranium and plutonium in Russia and the UK. This work examines the CSD mortality after chronic intake of uranium among 2897 workers (79,892 person-years) at a uranium processing plant (1960-2006) in France. Cumulative exposure to different uranium compounds, classified by their isotopic composition and solubility type, was quantified on the basis of a plant-specific job-exposure matrix and individual job histories. HRs and associated 95% CI for CSD (n = 111) and specific CSD categories were estimated using Cox regression models, stratified on sex and birth cohort and adjusted for potential confounders. The effect of smoking was analysed among 260 smokers (42 CSD deaths). Compared to unexposed workers, CSD mortality was increased among workers exposed to slowly soluble reprocessed uranium (RPU) (HR = 2.13, 95% CI = 0.96 to 4.70) and natural uranium (HR = 1.73, 95% CI = 1.11 to 2.69). The risk increased with cumulative exposure and exposure duration. In the subgroup of smokers, the risk estimates were higher but with larger CIs: HR=1.91 (95% CI = 0.92 to 3.98) for natural uranium and HR = 4.78 (95% CI = 1.38 to 16.50) for RPU. The authors observed that exposure to slowly soluble uranium, namely RPU, may increase the risk of CSD mortality. However, these results are preliminary since the study is lacking statistical power and many other biological and lifestyle-related factors may cause CSD. More detailed investigations are necessary to confirm these findings and analyse in depth the effects of internal radiation exposure on the circulatory system.

  5. Human Factors Engineering and Ergonomics in Systems Engineering

    NASA Technical Reports Server (NTRS)

    Whitmore, Mihriban

    2017-01-01

    The study, discovery, and application of information about human abilities, human limitations, and other human characteristics to the design of tools, devices, machines, systems, job tasks and environments for effective human performance.

  6. A Novel Human Autonomy Assessment System

    PubMed Central

    Munstermann, Marco; Stevens, Torsten; Luther, Wolfram

    2012-01-01

    This article presents a novel human autonomy assessment system for generating context and discovering the behaviors of older people who use ambulant services. Our goal is to assist caregivers in assessing possibly abnormal health conditions in their clients concerning their level of autonomy, thus enabling caregivers to take countermeasures as soon as possible. PMID:22969374

  7. How to Bootstrap a Human Communication System

    ERIC Educational Resources Information Center

    Fay, Nicolas; Arbib, Michael; Garrod, Simon

    2013-01-01

    How might a human communication system be bootstrapped in the absence of conventional language? We argue that motivated signs play an important role (i.e., signs that are linked to meaning by structural resemblance or by natural association). An experimental study is then reported in which participants try to communicate a range of pre-specified…

  8. The Human Resources Management System: Part 1.

    ERIC Educational Resources Information Center

    Ceriello, Vincent R.

    1982-01-01

    Presents a systematic and disciplined approach to planning for the development and implementation of an information system which will collect, store, maintain, and report human resources data. Discusses guidelines, priorities, training requirements, security, auditing, interface with payroll, and personnel reporting. (CT)

  9. Ruminococcal cellulosome systems from rumen to human.

    PubMed

    Ben David, Yonit; Dassa, Bareket; Borovok, Ilya; Lamed, Raphael; Koropatkin, Nicole M; Martens, Eric C; White, Bryan A; Bernalier-Donadille, Annick; Duncan, Sylvia H; Flint, Harry J; Bayer, Edward A; Moraïs, Sarah

    2015-09-01

    A cellulolytic fiber-degrading bacterium, Ruminococcus champanellensis, was isolated from human faecal samples, and its genome was recently sequenced. Bioinformatic analysis of the R. champanellensis genome revealed numerous cohesin and dockerin modules, the basic elements of the cellulosome, and manual sequencing of partially sequenced genomic segments revealed two large tandem scaffoldin-coding genes that form part of a gene cluster. Representative R. champanellensis dockerins were tested against putative cohesins, and the results revealed three different cohesin-dockerin binding profiles which implied two major types of cellulosome architectures: (i) an intricate cell-bound system and (ii) a simplistic cell-free system composed of a single cohesin-containing scaffoldin. The cell-bound system can adopt various enzymatic architectures, ranging from a single enzyme to a large enzymatic complex comprising up to 11 enzymes. The variety of cellulosomal components together with adaptor proteins may infer a very tight regulation of its components. The cellulosome system of the human gut bacterium R. champanellensis closely resembles that of the bovine rumen bacterium Ruminococcus flavefaciens. The two species contain orthologous gene clusters comprising fundamental components of cellulosome architecture. Since R. champanellensis is the only human colonic bacterium known to degrade crystalline cellulose, it may thus represent a keystone species in the human gut. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. How to Bootstrap a Human Communication System

    ERIC Educational Resources Information Center

    Fay, Nicolas; Arbib, Michael; Garrod, Simon

    2013-01-01

    How might a human communication system be bootstrapped in the absence of conventional language? We argue that motivated signs play an important role (i.e., signs that are linked to meaning by structural resemblance or by natural association). An experimental study is then reported in which participants try to communicate a range of pre-specified…

  11. Visuals and Visualisation of Human Body Systems

    ERIC Educational Resources Information Center

    Mathai, Sindhu; Ramadas, Jayashree

    2009-01-01

    This paper explores the role of diagrams and text in middle school students' understanding and visualisation of human body systems. We develop a common framework based on structure and function to assess students' responses across diagram and verbal modes. Visualisation is defined in terms of understanding transformations on structure and relating…

  12. First Human Systemic Infection Caused by Spiroplasma

    PubMed Central

    Aquilino, Ana; López, Pilar; Galiana, Antonio J.; Tovar, Juan; Andrés, María; Gutiérrez, Félix

    2014-01-01

    Spiroplasma species are organisms that normally colonize plants and insects. We describe the first case of human systemic infection caused by Spiroplasma bacteria in a patient with hypogammaglobulinemia undergoing treatment with biological disease-modifying antirheumatic agents. Spiroplasma turonicum was identified through molecular methods in several blood cultures. The infection was successfully treated with doxycycline plus levofloxacin. PMID:25428150

  13. Visuals and Visualisation of Human Body Systems

    ERIC Educational Resources Information Center

    Mathai, Sindhu; Ramadas, Jayashree

    2009-01-01

    This paper explores the role of diagrams and text in middle school students' understanding and visualisation of human body systems. We develop a common framework based on structure and function to assess students' responses across diagram and verbal modes. Visualisation is defined in terms of understanding transformations on structure and relating…

  14. The Human Operator and System Effectiveness.

    DTIC Science & Technology

    1984-06-01

    Farm Worker stand the design process. 5. Managers Branch Chief Coordinate and direct Project Head work. Program Manager Team Leader 6. The Principal... Biodynamics Laboratory, New Orleans (Lcdr. J. Pollack) 3 Naval Ocean Systems Center, San Diego Human Factors Group (1) Signal Analysis and Display Division

  15. The human brain intracerebral microvascular system: development and structure

    PubMed Central

    Marín-Padilla, Miguel

    2012-01-01

    The capillary from the meningeal inner pial lamella play a crucial role in the development and structural organization of the cerebral cortex extrinsic and intrinsic microvascular compartments. Only pial capillaries are capable of perforating through the cortex external glial limiting membrane (EGLM) to enter into the nervous tissue, although incapable of perforating the membrane to exit the brain. Circulatory dynamics and functional demands determine which capillaries become arterial and which capillaries become venous. The perforation of the cortex EGLM by pial capillaries is a complex process characterized by three fundamental stages: (1) pial capillary contact with the EGLM with fusion of vascular and glial basal laminae at the contact site, (2) endothelial cell filopodium penetration through the fussed laminae with the formation of a funnel between them that accompanies it into the nervous tissue while remaining open to the meningeal interstitium and, (3) penetration of the whole capillary carrying the open funnel with it and establishing an extravascular Virchow-Robin Compartment (V-RC) that maintains the perforating vessel extrinsic (outside) the nervous tissue through its entire length. The V-RC is walled internally by the vascular basal lamina and externally by the basal lamina of joined glial cells endfeet. The VRC outer glial wall appear as an extension of the cortex superficial EGLM. All the perforating vessels within the V-RCs constitute the cerebral cortex extrinsic microvascular compartment. These perforating vessels are the only one capable of responding to inflammatory insults. The V-RC remains open (for life) to the meningeal interstitium permitting the exchanges of fluid and of cells between brain and meninges. The V-RC function as the brain sole drainage (prelymphatic) system in both physiological as well as pathological situations. During cortical development, capillaries emerge from the perforating vessels, by endothelial cells growing sprouts

  16. Human circulating dopamine-beta-hydroxylase and epilepsy.

    PubMed

    Warter, J M; Coquillat, G; Kurtz, D

    1975-01-01

    The activity of circulatory dopamine-beta-hydroxylase (DBH) in humans is shown to be lower in some epileptic subjects than in normal subjects. The activity of the enzymes was found to be dramatically low in subjects who experienced an epileptic seizure 24 hrs before DBH activity was determined. The activity varied through the course of epileptic seizures induced by a convulsant drugs and these variations might be due to the "en masse" changes of the sympathetic nervous system.

  17. The prevention of transfusion-associated circulatory overload.

    PubMed

    Alam, Asim; Lin, Yulia; Lima, Ana; Hansen, Mark; Callum, Jeannie L

    2013-04-01

    Transfusion-associated circulatory overload (TACO) is an important and potentially injurious complication of transfusion that is underappreciated by clinicians. Risk factors for TACO include being at an extreme of age, having preexisting cardiac and/or (potentially) renal dysfunction, acute myocardial infarction, and individuals receiving plasma. Keys to preventing TACO, aside from identifying high-risk individuals, should be multifaceted. We advocate for the widespread use of pretransfusion checklists and implementation of nonemergent transfusion protocols. We suggest the regular use of pretransfusion diuretics in high-risk individuals. When a transfusion is required, we believe that "critical" nursing supervision and leadership are instrumental in the coordination of slow transfusion rates on computerized infusion pumps and ensuring patients are appropriately monitored. We believe that using these methodologies on a global scale will prevent many TACO events and minimize the severity when it does occur.

  18. Deep hypothermic circulatory arrest: real-life suspended animation.

    PubMed

    Chau, Katherine H; Ziganshin, Bulat A; Elefteriades, John A

    2013-01-01

    Deep hypothermic circulatory arrest (DHCA) is a cerebral protection technique that was developed in the 1950s and popularized in the 1970s. It has become one of the three most common cerebral protection techniques currently used in aortic arch surgeries, with the other two being antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). At our institution, DHCA has been the cerebral protection technique of choice for over a quarter century. Our clinical experience with DHCA has been very positive, and our clinical studies have shown DHCA to have outcomes equal to (and sometimes better than) those of ACP and RCP, and DHCA to be very effective at preserving neurocognitive function. Other institutions, however, prefer ACP or RCP to DHCA. Each technique has its own set of pros and cons, and the question regarding which technique is the superior method for cerebral protection is hotly debated.

  19. Improved mechanism for capturing muscle power for circulatory support.

    PubMed

    Trumble, Dennis R; Melvin, David B; Byrne, Mark T; Magovern, James A

    2005-09-01

    Although it is now understood that trained skeletal muscle can generate enough steady-state power to provide significant circulatory support, there are currently no means by which to tap this endogenous energy source to aid the failing heart. To that end, an implantable muscle energy converter (MEC) has been constructed and its function has been improved to optimize durability, anatomic fit, and mechanical efficiency. Bench tests show that MEC transmission losses average less than 10% of total work input and that about 85% of this muscle power is successfully transferred to the working fluid of the pump. Results from canine implant trials confirm excellent biocompatibility and demonstrate that contractile work of the latissimus dorsi muscle-measured to 290 mJ/stroke in one dog-can be transmitted within the body at levels consistent with cardiac assist requirements. These findings suggest that muscle-powered cardiac assist devices are feasible and that efforts to further develop this technology are warranted.

  20. The NATO Unmanned Aircraft System Human Systems Integration Guidebook

    DTIC Science & Technology

    2012-11-01

    training, refresher training, and core competency-based training • Teamwork /crew resource management • Balance of live flying training, embedded...architecture framework. Its purpose is to visualize and facilitate understanding of the human dimension in relation to operational demands and system...anthropometric/medical data; reach data; range of motion data; physical strength data; human sensory (e.g., visual , auditory, tactile, propioceptive

  1. Infection after implantation of pulsatile mechanical circulatory support devices.

    PubMed

    Holman, William L; Kirklin, James K; Naftel, David C; Kormos, Robert L; Desvign-Nickens, Patricia; Camacho, Margarita T; Ascheim, Deborah D

    2010-06-01

    INTERMACS is a registry of mechanical circulatory support devices sponsored by the National Institutes of Health. This analysis uses INTERMACS data to define the time course, incidence, and outcome of infection adverse events focusing on the first 3 months after implant. Patients entered into INTERMACS from June 23, 2006, to September 30, 2008, were analyzed. Preimplant data (demographics, hemodynamics, and laboratory values), infection adverse events, and other outcomes were recorded. Infection adverse events were analyzed to compare infection rates in subgroups of patients and define risk factors for death. The analysis was confined to pulsatile mechanical circulatory support devices. A total of 593 patients from 88 institutions were entered. Infection was a relatively common event within the first 3 months of implant and was significantly (P = .005) more common in patients with biventricular assist devices than in patients with left ventricular assist devices, although the prevalence of infection equalized in months 4 to 12. Infection had a significant adverse effect on survival. Independent risk factors for death included support with a biventricular assist device, older age, severity of patient illness implantation of the device (INTERMACS level 1), and higher blood urea nitrogen. Infection remains a relatively frequent adverse event and is associated with decreased survival. Interventions to prevent infection that focus on the preoperative and immediate postoperative periods are the ones most likely to achieve success by diminishing the incidence of infection during the initial 3 months after implantation. Rotary (continuous-flow) pumps are expected to have lower infection rates, but this remains to be seen. Published by Mosby, Inc.

  2. Donation after circulatory death: a national survey of current practice in England in 2012.

    PubMed

    Patel, Sameer; Martin, Jonathan R; Marino, Philip S

    2014-10-01

    In recent years, England has seen renewed interest in donation after circulatory death. Many national and local initiatives have been implemented to encourage and support donation after circulatory death. To assess whether practice is in line with published guidance, we conducted a national survey with regard to current donation after circulatory death practices, local guidelines, and views on the need to further develop a national standardized protocol for donation after circulatory death. Online survey. Lead physicians for intensive care or organ donation for every acute National Health Service trust in England delivering adult care between April and June 2012. Physicians were e-mailed a link to a structured online questionnaire regarding their experience and practice of donation after circulatory death, including local protocols, use of organ optimization, and the need for a national protocol. We received replies from 119 of 156 eligible trusts (76.3%) in England. Of these, 112 trusts (94%) have performed donation after circulatory death. Ninety-three trusts (78.1%) have a local donation after circulatory death protocol, and 89 trusts (74.7%) felt there should be a national donation after circulatory death protocol. All responding transplant centers had performed donation after circulatory death, 14 of 17 (82.3%) had a donation after circulatory death protocol with 14 of 17 respondents (82.3%) supporting a national protocol. Regarding organ optimization, 92 institutions (77.3%) used vasoactive drugs to achieve a target mean arterial blood pressure with 82 centers (68.9%) employing positive end-expiratory pressure and FIO2 to optimize oxygenation. Eight centers (6.7%) used heparin premortem compared with two of 17 transplant centers (11.8%). Two centers have used phentolamine to facilitate organ retrieval, with another five centers (4.2%) cannulating vessels premortem. Our survey revealed varying approaches and views toward donation after circulatory death across

  3. Fingertips detection for human computer interaction system

    NASA Astrophysics Data System (ADS)

    Alam, Md. Jahangir; Nasierding, Gulisong; Sajjanhar, Atul; Chowdhury, Morshed

    2014-01-01

    Fingertips of human hand play an important role in hand-based interaction with computers. Identification of fingertips' positions in hand images is vital for developing a human computer interaction system. This paper proposes a novel method for detecting fingertips of a hand image analyzing the concept of the geometrical structural information of fingers. The research is divided into three parts: First, hand image is segmented for detecting hand; Second, invariant features (curvature zero-crossing points) are extracted from the boundary of the hand; Third, fingertips are detected. Experimental results show that the proposed approach is promising.

  4. Project ATHENA Creates Surrogate Human Organ Systems

    ScienceCinema

    MacQueen, Luke; Knospel, Fanny; Sherrod, Stacy; Iyer, Rashi

    2016-07-12

    The development of miniature surrogate human organs, coupled with highly sensitive mass spectrometry technologies, could one day revolutionize the way new drugs and toxic agents are studied. “By developing this ‘homo minutus,’ we are stepping beyond the need for animal or Petri dish testing: There are huge benefits in developing drug and toxicity analysis systems that can mimic the response of actual human organs,” said Rashi Iyer, a senior scientist at Los Alamos National Laboratory. ATHENA, the Advanced Tissue-engineered Human Ectypal Network Analyzer project team, is nearing the full integration of four human organ constructs — liver, heart, lung and kidney — each organ component is about the size of a smartphone screen, and the whole ATHENA “body” of interconnected organs will fit neatly on a desk. A new video available on the Los Alamos National Laboratory YouTube channel updates the ATHENA project as it begins to integrate the various organ systems into a single system (link to video here). Some 40 percent of pharmaceuticals fail their clinical trials and there are thousands of chemicals whose effects on humans are simply unknown. Providing a realistic, cost-effective and rapid screening system such as ATHENA with high-throughput capabilities could provide major benefits to the medical field, screening more accurately and offering a greater chance of clinical trial success. ATHENA is funded by the Defense Threat Reduction Agency (DTRA) and is a collaboration of Los Alamos National Laboratory, Harvard University, Vanderbilt University, Charité Universitätsmedizin, Berlin, Germany, CFD Research Corporation, and the University of California San Francisco.

  5. Project ATHENA Creates Surrogate Human Organ Systems

    SciTech Connect

    MacQueen, Luke; Knospel, Fanny; Sherrod, Stacy; Iyer, Rashi

    2015-06-15

    The development of miniature surrogate human organs, coupled with highly sensitive mass spectrometry technologies, could one day revolutionize the way new drugs and toxic agents are studied. “By developing this ‘homo minutus,’ we are stepping beyond the need for animal or Petri dish testing: There are huge benefits in developing drug and toxicity analysis systems that can mimic the response of actual human organs,” said Rashi Iyer, a senior scientist at Los Alamos National Laboratory. ATHENA, the Advanced Tissue-engineered Human Ectypal Network Analyzer project team, is nearing the full integration of four human organ constructs — liver, heart, lung and kidney — each organ component is about the size of a smartphone screen, and the whole ATHENA “body” of interconnected organs will fit neatly on a desk. A new video available on the Los Alamos National Laboratory YouTube channel updates the ATHENA project as it begins to integrate the various organ systems into a single system (link to video here). Some 40 percent of pharmaceuticals fail their clinical trials and there are thousands of chemicals whose effects on humans are simply unknown. Providing a realistic, cost-effective and rapid screening system such as ATHENA with high-throughput capabilities could provide major benefits to the medical field, screening more accurately and offering a greater chance of clinical trial success. ATHENA is funded by the Defense Threat Reduction Agency (DTRA) and is a collaboration of Los Alamos National Laboratory, Harvard University, Vanderbilt University, Charité Universitätsmedizin, Berlin, Germany, CFD Research Corporation, and the University of California San Francisco.

  6. Human performance modeling for system of systems analytics :soldier fatigue.

    SciTech Connect

    Lawton, Craig R.; Campbell, James E.; Miller, Dwight Peter

    2005-10-01

    The military has identified Human Performance Modeling (HPM) as a significant requirement and challenge of future systems modeling and analysis initiatives as can be seen in the Department of Defense's (DoD) Defense Modeling and Simulation Office's (DMSO) Master Plan (DoD 5000.59-P 1995). To this goal, the military is currently spending millions of dollars on programs devoted to HPM in various military contexts. Examples include the Human Performance Modeling Integration (HPMI) program within the Air Force Research Laboratory, which focuses on integrating HPMs with constructive models of systems (e.g. cockpit simulations) and the Navy's Human Performance Center (HPC) established in September 2003. Nearly all of these initiatives focus on the interface between humans and a single system. This is insufficient in the era of highly complex network centric SoS. This report presents research and development in the area of HPM in a system-of-systems (SoS). Specifically, this report addresses modeling soldier fatigue and the potential impacts soldier fatigue can have on SoS performance.

  7. Structural design of a newly developed pediatric circulatory assist device for Fontan circulation by using shape memory alloy fiber.

    PubMed

    Shiraishi, Y; Sugai, T K; Tanaka, A; Yoshizawa, M; Yambe, T; Yamada, A; Omran, M H; Shiga, T; Kitano, T; Kamiya, K; Mochizuki, S; Miura, H; Homma, D; Yamagishi, M

    2011-01-01

    Total cavopulmonary connection (TCPC) is commonly applied for the surgical treatment of congenital heart disease such as single ventricle in pediatric patients. Patients with no ventricle in pulmonary circulation are treated along with Fontan algorithm, in which the systemic venous return is diverted directly to the pulmonary artery without passing through subpulmonary ventricle. In order to promote the pulmonary circulation after Fontan procedure, we developed a newly designed pulmonary circulatory assist device by using shape memory alloy fibers. We developed a pulmonary circulatory assist device as a non-blood contacting mechanical support system in pediatric patients with TCPC. The device has been designed to be installed like a cuff around the ePTFE TCPC conduit, which can contract from outside. We employed a covalent type functional anisotropic shape memory alloy fiber (Biometal, Toki Corporation, Tokyo Japan) as a servo actuator of the pulmonary circulatory assist device. The diameter of this fiber was 100 microns, and its contractile frequency was 2-3 Hz. Heat generation with electric current contracts these fibers and the conduit. The maximum contraction ratio of this fiber is about 7% in length. In order to extend its contractile ratio, we fabricated and installed mechanical structural units to control the length of fibers. In this study, we examined basic contractile functions of the device in the mock system. As a result, the internal pressure of the conduit increased to 63 mmHg by the mechanical contraction under the condition of 400 msec-current supply in the mock examination with the overflow tank of 10 mmHg loading.

  8. Human eye color difference threshold measurement system

    NASA Astrophysics Data System (ADS)

    Liu, Lin; Zhou, Taogeng

    2013-12-01

    The human eye has the ability to distinguish millions of colors, with this feature we can identify very subtle color differences, and the measurement of human eye color difference threshold can provide a visual function diagnosis for testee. In recent years, people begin to focus on studies on visual threshold diagnostic equipment. This paper proposes a human eye color difference threshold measurement system which is based on dual integrating sphere. The system includes two pairs of dual integrating sphere and color control module. Dual integrating sphere uses to mix and produce color, and palette unit which produces primary colors (red (R), green (G), blue (B)) is embedded in dual integrating sphere. At the same time, the embedded palette unit which produces cyan (C), magenta (M), and yellow (Y) expands color area that the system can generate. One optical path based on dual integrating sphere generates standard color, the other path produces the matching color which is similar to a standard color. In the high-precision closed-loop color control module, photoelectric switch records stepper motor's origin position and limits move displacement. Precision stepper motor pushes the light-blocking panel of the palette unit to a predetermined position, while real-time monitoring the position of the light-blocking panel and mixing the ideal controllable color. Two colors that the system generates are projected onto the same target area. Subjects make a judgment on color difference threshold by observing the target eventually.

  9. Human factors in high consequence manufacturing systems

    SciTech Connect

    Forsythe, C.; Grose, E.

    1997-11-01

    A high consequence system is often defined as one in which the potential exists for severe or catastrophic accidents. Familiar examples include nuclear power plants, airline and other mass transportation, dams and reservoirs, and large-scale food processing. Many manufacturing systems also qualify as high consequence systems. Much of the authors` experience with high consequence systems derives from work associated with the surveillance and dismantlement of nuclear weapons for the US Department of Energy. With such operations, there exists a risk of high explosive detonation accompanied by radiological dispersal and, potentially, nuclear detonation. Analysis of major industrial accidents such as Three Mile Island, Chernobyl and Bhopal have revealed that these incidents were not attributable to a single event or direct cause, but were the result of multiple factors that combined to create a condition ripe for an accident. In each case, human error was a critical factor contributing to the accident. Consequently, many authors have emphasized the need for greater appreciation of systematic factors and in particular, human activities. This paper discusses approaches used in hazard analysis of US nuclear weapons operations to assess risk associated with human factors.

  10. Risk Factors and Clinical Outcomes Associated with Perioperative Transfusion-associated Circulatory Overload.

    PubMed

    Clifford, Leanne; Jia, Qing; Subramanian, Arun; Yadav, Hemang; Schroeder, Darrell R; Kor, Daryl J

    2017-03-01

    Transfusion-associated circulatory overload remains underappreciated in the perioperative environment. The authors aimed to characterize risk factors for perioperative transfusion-associated circulatory overload and better understand its impact on patient-important outcomes. In this case-control study, 163 adults undergoing noncardiac surgery who developed perioperative transfusion-associated circulatory overload were matched with 726 transfused controls who did not develop respiratory complications. Univariate and multivariable logistic regression analyses were used to evaluate potential risk factors for transfusion-associated circulatory overload. The need for postoperative mechanical ventilation, lengths of intensive care unit and hospital stay, and mortality were compared. For this cohort, the mean age was 71 yr and 56% were men. Multivariable analysis revealed the following independent predictors of transfusion-associated circulatory overload: emergency surgery, chronic kidney disease, left ventricular dysfunction, previous β-adrenergic receptor antagonist use, isolated fresh frozen plasma transfusion (vs. isolated erythrocyte transfusion), mixed product transfusion (vs. isolated erythrocyte transfusion), and increasing intraoperative fluid administration. Patients who developed transfusion-associated circulatory overload were more likely to require postoperative mechanical ventilation (73 vs. 33%; P < 0.001) and experienced prolonged intensive care unit (11.1 vs. 6.5 days; P < 0.001) and hospital lengths of stay (19.9 vs. 9.6 days; P < 0.001). Survival was significantly reduced (P < 0.001) in transfusion recipients who developed transfusion-associated circulatory overload (1-yr survival 72 vs. 84%). Perioperative transfusion-associated circulatory overload was associated with a protracted hospital course and increased mortality. Efforts to minimize the incidence of transfusion-associated circulatory overload should focus on the judicious use of

  11. Hot-water heating system having an air eliminator

    SciTech Connect

    Pompei, F.

    1984-06-26

    An improved forced-liquid flow, circulatory system for removing gas entrained or dissolved in the liquid. The system includes a circulatory liquid-flow network and means for forcing the liquid to flow through the circulatory network. A by-pass line is situated around the region where the lowest gas solubility in the liquid occurs in the circulatory network. Such lowest gas solubility occurs at the point of generally highest temperature and lowest pressure, as determined most precisely by Henry's Law. Gas-liquid separator means is located in the by-pass line. The separator means separates the gas from the liquid and expels the gas from the circulatory network.

  12. An Empirical Methodology for Engineering Human Systems Integration

    DTIC Science & Technology

    2009-12-01

    Human factors engineering HFI ...................................... Human factors integration HMI .................................... Human...AIRPRINT AFRL/RH INCOSE Defense Acquisition Guide MANPRINT IEEE SMC ACM UK HFI Program Manpower X X X X X X X Personnel X X X “Personal...systems engineering human systems integration NATO, some use USAF, ISO HFI Human factors integration Confused with HSI, but only the interface

  13. Dynamics of coupled human-landscape systems

    NASA Astrophysics Data System (ADS)

    Werner, B. T.; McNamara, D. E.

    2007-11-01

    A preliminary dynamical analysis of landscapes and humans as hierarchical complex systems suggests that strong coupling between the two that spreads to become regionally or globally pervasive should be focused at multi-year to decadal time scales. At these scales, landscape dynamics is dominated by water, sediment and biological routing mediated by fluvial, oceanic, atmospheric processes and human dynamics is dominated by simplifying, profit-maximizing market forces and political action based on projection of economic effect. Also at these scales, landscapes impact humans through patterns of natural disasters and trends such as sea level rise; humans impact landscapes by the effect of economic activity and changes meant to mitigate natural disasters and longer term trends. Based on this analysis, human-landscape coupled systems can be modeled using heterogeneous agents employing prediction models to determine actions to represent the nonlinear behavior of economic and political systems and rule-based routing algorithms to represent landscape processes. A cellular model for the development of New Orleans illustrates this approach, with routing algorithms for river and hurricane-storm surge determining flood extent, five markets (home, labor, hotel, tourism and port services) connecting seven types of economic agents (home buyers/laborers, home developers, hotel owners/ employers, hotel developers, tourists, port services developer and port services owners/employers), building of levees or a river spillway by political agents and damage to homes, hotels or port services within cells determined by the passage or depth of flood waters. The model reproduces historical aspects of New Orleans economic development and levee construction and the filtering of frequent small-scale floods at the expense of large disasters.

  14. Integrating Spaceflight Human System Risk Research

    NASA Technical Reports Server (NTRS)

    Mindock, Jennifer; Lumpkins, Sarah; Anton, Wilma; Havenhill, Maria; Shelhamer, Mark; Canga, Michael

    2016-01-01

    NASA is working to increase the likelihood of human health and performance success during exploration missions as well as to maintain the subsequent long-term health of the crew. To manage the risks in achieving these goals, a system modelled after a Continuous Risk Management framework is in place. "Human System Risks" (Risks) have been identified, and approximately 30 are being actively addressed by NASA's Human Research Program (HRP). Research plans for each of HRP's Risks have been developed and are being executed. Inter-disciplinary ties between the research efforts supporting each Risk have been identified; however, efforts to identify and benefit from these connections have been mostly ad hoc. There is growing recognition that solutions developed to address the full set of Risks covering medical, physiological, behavioural, vehicle, and organizational aspects of exploration missions must be integrated across Risks and disciplines. This paper discusses how a framework of factors influencing human health and performance in space is being applied as the backbone for bringing together sometimes disparate information relevant to the individual Risks. The resulting interrelated information enables identification and visualization of connections between Risks and research efforts in a systematic and standardized manner. This paper also discusses the applications of the visualizations and insights into research planning, solicitation, and decision-making processes.

  15. Integrating Spaceflight Human System Risk Research

    NASA Technical Reports Server (NTRS)

    Mindock, J.; Lumpkins, S.; Anton, W.; Havenhill, M.; Shelhamer, M.; Canga, M.

    2016-01-01

    NASA is working to increase the likelihoods of human health and performance success during exploration missions, and subsequent crew long-term health. To manage the risks in achieving these goals, a system modeled after a Continuous Risk Management framework is in place. "Human System Risks" (Risks) have been identified, and approximately 30 are being actively addressed by NASA's Human Research Program (HRP). Research plans for each of HRP's Risks have been developed and are being executed. Ties between the research efforts supporting each Risk have been identified, however, this has been in an ad hoc fashion. There is growing recognition that solutions developed to address the full set of Risks covering medical, physiological, behavioral, vehicle, and organizational aspects of the exploration missions must be integrated across Risks and disciplines. We will discuss how a framework of factors influencing human health and performance in space is being applied as the backbone for bringing together sometimes disparate information relevant to the individual Risks. The resulting interrelated information is allowing us to identify and visualize connections between Risks and research efforts in a systematic and standardized way. We will discuss the applications of the visualizations and insights to research planning, solicitation, and decision-making processes.

  16. Mapping the Human Toxome by Systems Toxicology

    PubMed Central

    Bouhifd, Mounir; Hogberg, Helena T.; Kleensang, Andre; Maertens, Alexandra; Zhao, Liang; Hartung, Thomas

    2014-01-01

    Toxicity testing typically involves studying adverse health outcomes in animals subjected to high doses of toxicants with subsequent extrapolation to expected human responses at lower doses. The low-throughput of current toxicity testing approaches (which are largely the same for industrial chemicals, pesticides and drugs) has led to a backlog of more than 80,000 chemicals to which human beings are potentially exposed whose potential toxicity remains largely unknown. Employing new testing strategies that employ the use of predictive, high-throughput cell-based assays (of human origin) to evaluate perturbations in key pathways, referred as pathways of toxicity, and to conduct targeted testing against those pathways, we can begin to greatly accelerate our ability to test the vast “storehouses” of chemical compounds using a rational, risk-based approach to chemical prioritization, and provide test results that are more predictive of human toxicity than current methods. The NIH Transformative Research Grant project Mapping the Human Toxome by Systems Toxicology aims at developing the tools for pathway mapping, annotation and validation as well as the respective knowledge base to share this information. PMID:24443875

  17. Human Frontal Lobes and AI Planning Systems

    NASA Technical Reports Server (NTRS)

    Levinson, Richard; Lum, Henry Jr. (Technical Monitor)

    1994-01-01

    Human frontal lobes are essential for maintaining a self-regulating balance between predictive and reactive behavior. This paper describes a system that integrates prediction and reaction based on neuropsychological theories of frontal lobe function. In addition to enhancing our understanding of deliberate action in humans' the model is being used to develop and evaluate the same properties in machines. First, the paper presents some background neuropsychology in order to set a general context. The role of frontal lobes is then presented by summarizing three theories which formed the basis for this work. The components of an artificial frontal lobe are then discussed from both neuropsychological and AI perspectives. The paper concludes by discussing issues and methods for evaluating systems that integrate planning and reaction.

  18. Biotransport in the human respiratory system.

    PubMed

    Elad, D

    1999-01-01

    The human respiratory system is an 'open' organ, which is designed to exchange oxygen and carbon dioxide between the circulating blood and the external environment. This gas exchange is successfully accomplished via a set of transport phenomena comprised of oscillatory air flow, heat and water vapor exchange, mucus transport and air-blood gas exchange all of which take place in a complex geometry that undergoes large changes. These transport phenomena occur simultaneously to supply the body's need for oxygen in different physiological conditions and/or environments, while defending it from external hazards. The need for better comprehension of the mechanisms involved in pulmonary diseases and for advanced techniques for both diagnosis and intervention stimulated numerous studies of the different biotransport processes that take place in the human respiratory system.

  19. HSI Prototypes for Human Systems Simulation Laboratory

    SciTech Connect

    Jokstad, Håkon; McDonald, Rob

    2015-09-01

    This report describes in detail the design and features of three Human System Interface (HSI) prototypes developed by the Institutt for Energiteknikk (IFE) in support of the U.S. Department of Energy’s Light Water Reactor Sustainability Program under Contract 128420 through Idaho National Laboratory (INL). The prototypes are implemented for the Generic Pressurized Water Reactor simulator and installed in the Human Systems Simulation Laboratory at INL. The three prototypes are: 1) Power Ramp display 2) RCS Heat-up and Cool-down display 3) Estimated time to limit display The power ramp display and the RCS heat-up/cool-down display are designed to provide good visual indications to the operators on how well they are performing their task compared to their target ramp/heat-up/cool-down rate. The estimated time to limit display is designed to help operators restore levels or pressures before automatic or required manual actions are activated.

  20. Human Frontal Lobes and AI Planning Systems

    NASA Technical Reports Server (NTRS)

    Levinson, Richard; Lum, Henry Jr. (Technical Monitor)

    1994-01-01

    Human frontal lobes are essential for maintaining a self-regulating balance between predictive and reactive behavior. This paper describes a system that integrates prediction and reaction based on neuropsychological theories of frontal lobe function. In addition to enhancing our understanding of deliberate action in humans' the model is being used to develop and evaluate the same properties in machines. First, the paper presents some background neuropsychology in order to set a general context. The role of frontal lobes is then presented by summarizing three theories which formed the basis for this work. The components of an artificial frontal lobe are then discussed from both neuropsychological and AI perspectives. The paper concludes by discussing issues and methods for evaluating systems that integrate planning and reaction.