The Relationship between Rumination and Affective, Cognitive, and Physiological Responses to Stress in Adolescents.

PubMed

Aldao, Amelia; McLaughlin, Katie A; Hatzenbuehler, Mark L; Sheridan, Margaret A

Although previous studies have established that rumination influences responses to stressful life events, the mechanisms underlying this relationship remain inadequately understood. The current study examines the relationship between trait rumination and affective, cognitive, and physiological responses to a standardized laboratory-based stressor in adolescents. A community-based sample of adolescents (N = 157) aged 13-17 completed the Trier Social Stress Test (TSST). Affective, cognitive, and physiological responses were obtained before, during, and after the TSST. Adolescents who engaged in habitual rumination experienced greater negative affect and more negative cognitive appraisals in response to the TSST than adolescents with lower levels of rumination. Rumination was unrelated to heart rate reactivity, but predicted slower heart rate recovery from the TSST, indicating that rumination might be specifically associated with physiological recovery from stress. Rumination is associated with negative affective, cognitive, and physiological responses following stressors, suggesting potential mechanisms through which it might increase risk for psychopathology.

[Physiological features of skin ageing in human].

PubMed

Tikhonova, I V; Tankanag, A V; Chemeris, N K

2013-01-01

The issue deals with the actual problem of gerontology, notably physiological features of human skin ageing. In the present review the authors have considered the kinds of ageing, central factors, affected on the ageing process (ultraviolet radiation and oxidation stress), as well as the research guidelines of the ageing changes in the skin structure and fuctions: study of mechanical properties, microcirculation, pH and skin thickness. The special attention has been payed to the methods of assessment of skin blood flow, and to results of investigations of age features of peripheral microhemodynamics. The laser Doppler flowmetry technique - one of the modern, noninvasive and extensively used methods for the assessmant of skin blood flow microcirculation system has been expanded in the review. The main results of the study of the ageing changes of skin blood perfusion using this method has been also presented.

Do Targeted Written Comments and the Rubric Method of Delivery Affect Performance on Future Human Physiology Laboratory Reports?

ERIC Educational Resources Information Center

Clayton, Zachary S.; Wilds, Gabriel P.; Mangum, Joshua E.; Hocker, Austin D.; Dawson, Sierra M.

2016-01-01

We investigated how students performed on weekly two-page laboratory reports based on whether the grading rubric was provided to the student electronically or in paper form and the inclusion of one- to two-sentence targeted comments. Subjects were registered for a 289-student, third-year human physiology class with laboratory and were randomized…

Human Adaptation to Space: Space Physiology and Countermeasures

NASA Technical Reports Server (NTRS)

Fogarty, Jennifer

2009-01-01

This viewgraph presentation reviews human physiological responses to spaceflight, and the countermeasures taken to prevent adverse effects of manned space flight. The topics include: 1) Human Spaceflight Experience; 2) Human Response to Spaceflight; 3) ISS Expeditions 1-16; 4) Countermeasure; and 5) Biomedical Data;

AN EXAMPLE OF MODEL STRUCTURE DIFFERENCES USING SENSITIVITY ANALYSES IN PHYSIOLOGICALLY BASED PHARMACOKINETIC MODELS OF TRICHLOROETHYLENE IN HUMANS

EPA Science Inventory

Abstract Trichloroethylene (TCE) is an industrial chemical and an environmental contaminant. TCE and its metabolites may be carcinogenic and affect human health. Physiologically based pharmacokinetic (PBPK) models that differ in compartmentalization are developed for TCE metabo...

Real-time Physiological Emotion Detection Mechanisms: Effects of Exercise and Affect Intensity.

PubMed

Leon, E; Clarke, G; Sepulveda, F; Callaghan, V

2005-01-01

The development of systems capable of recognizing and categorising emotions is of interest to researchers in various scientific areas including artificial intelligence. The traditional notion that emotions and rationality are two separate realms has gradually been challenged. The work of neurologists has shown the strong relationship between emotional episodes and the way humans think and act. Furthermore, emotions not only regulate human decisions but could also contribute to a more satisfactory response to the environment, i.e., faster and more precise actions. In this paper an analysis of physiological signals employed in real-time emotion detection is presented in the context of Intelligent Inhabited Environments (IIE). Two studies were performed to investigate whether physical exertion has a significant effect on bodily signals stemming from emotional episodes with subjects having various degrees of affect intensity: 1) a statistical analysis using the Wilcoxon Test, and 2) a cluster analysis using the Davies-Bouldin Index. Preliminary results demonstrated that the heart rate and skin resistance consistently showed similar changes regardless of the physical stimuli while blood volume pressure did not show a significant change. It was also found that neither physical stress nor affect intensity played a role in the separation of neutral and non-neutral emotional states.

Coupling of the Models of Human Physiology and Thermal Comfort

NASA Astrophysics Data System (ADS)

Pokorny, J.; Jicha, M.

2013-04-01

A coupled model of human physiology and thermal comfort was developed in Dymola/Modelica. A coupling combines a modified Tanabe model of human physiology and thermal comfort model developed by Zhang. The Coupled model allows predicting the thermal sensation and comfort of both local and overall from local boundary conditions representing ambient and personal factors. The aim of this study was to compare prediction of the Coupled model with the Fiala model prediction and experimental data. Validation data were taken from the literature, mainly from the validation manual of software Theseus-FE [1]. In the paper validation of the model for very light physical activities (1 met) indoor environment with temperatures from 12 °C up to 48 °C is presented. The Coupled model predicts mean skin temperature for cold, neutral and warm environment well. However prediction of core temperature in cold environment is inaccurate and very affected by ambient temperature. Evaluation of thermal comfort in warm environment is supplemented by skin wettedness prediction. The Coupled model is designed for non-uniform and transient environmental conditions; it is also suitable simulation of thermal comfort in vehicles cabins. The usage of the model is limited for very light physical activities up to 1.2 met only.

Emotional Processing in High-Functioning Autism--Physiological Reactivity and Affective Report

ERIC Educational Resources Information Center

Bolte, Sven; Feineis-Matthews, Sabine; Poustka, Fritz

2008-01-01

This study examined physiological response and affective report in 10 adult individuals with autism and 10 typically developing controls. An emotion induction paradigm using stimuli from the International Affective Picture System was applied. Blood pressure, heart and self-ratings of experienced valence (pleasure), arousal and dominance (control)…

Review of the physiology of human thermal comfort while exercising in urban landscapes and implications for bioclimatic design

NASA Astrophysics Data System (ADS)

Vanos, Jennifer K.; Warland, Jon S.; Gillespie, Terry J.; Kenny, Natasha A.

2010-07-01

This review comprehensively examines scientific literature pertaining to human physiology during exercise, including mechanisms of heat formation and dissipation, heat stress on the body, the importance of skin temperature monitoring, the effects of clothing, and microclimatic measurements. This provides a critical foundation for microclimatologists and biometeorologists in the understanding of experiments involving human physiology. The importance of the psychological aspects of how an individual perceives an outdoor environment are also reviewed, emphasizing many factors that can indirectly affect thermal comfort (TC). Past and current efforts to develop accurate human comfort models are described, as well as how these models can be used to develop resilient and comfortable outdoor spaces for physical activity. Lack of suitable spaces plays a large role in the deterioration of human health due to physical inactivity, leading to higher rates of illness, heart disease, obesity and heat-related casualties. This trend will continue if urban designers do not make use of current knowledge of bioclimatic urban design, which must be synthesized with physiology, psychology and microclimatology. Increased research is required for furthering our knowledge on the outdoor human energy balance concept and bioclimatic design for health and well-being in urban areas.

Review of the physiology of human thermal comfort while exercising in urban landscapes and implications for bioclimatic design.

PubMed

Vanos, Jennifer K; Warland, Jon S; Gillespie, Terry J; Kenny, Natasha A

2010-07-01

This review comprehensively examines scientific literature pertaining to human physiology during exercise, including mechanisms of heat formation and dissipation, heat stress on the body, the importance of skin temperature monitoring, the effects of clothing, and microclimatic measurements. This provides a critical foundation for microclimatologists and biometeorologists in the understanding of experiments involving human physiology. The importance of the psychological aspects of how an individual perceives an outdoor environment are also reviewed, emphasizing many factors that can indirectly affect thermal comfort (TC). Past and current efforts to develop accurate human comfort models are described, as well as how these models can be used to develop resilient and comfortable outdoor spaces for physical activity. Lack of suitable spaces plays a large role in the deterioration of human health due to physical inactivity, leading to higher rates of illness, heart disease, obesity and heat-related casualties. This trend will continue if urban designers do not make use of current knowledge of bioclimatic urban design, which must be synthesized with physiology, psychology and microclimatology. Increased research is required for furthering our knowledge on the outdoor human energy balance concept and bioclimatic design for health and well-being in urban areas.

[The effects of media violence on affective, cognitive, and physiological reactions of viewers].

PubMed

Yukawa, S; Yoshida, F

1998-06-01

The present study investigated the effects of media violence on affective, cognitive, and physiological reactions of viewers. Eighty undergraduate student (male = 40, female = 40) participated in the experiment. First, subjects were exposed to one of four violent films whose levels of violence and entertainment were based on ratings taken in a previous study (Yoshida & Yukawa, 1996). Immediately after viewing the film, subjects described their thoughts which occurred during watching the film and rated their affective reactions toward the film. Heart rate and eyeblink rate as indicators of physiological arousal were measured continuously before, during, and after the film. Results showed that the film high in violence elicited more negative and empty-powerless affects, while the film high in entertainment evoked more positive affects.

The physiological effects of slow breathing in the healthy human

PubMed Central

Russo, Marc A.; Santarelli, Danielle M.; O’Rourke, Dean

2017-01-01

Slow breathing practices have been adopted in the modern world across the globe due to their claimed health benefits. This has piqued the interest of researchers and clinicians who have initiated investigations into the physiological (and psychological) effects of slow breathing techniques and attempted to uncover the underlying mechanisms. The aim of this article is to provide a comprehensive overview of normal respiratory physiology and the documented physiological effects of slow breathing techniques according to research in healthy humans. The review focuses on the physiological implications to the respiratory, cardiovascular, cardiorespiratory and autonomic nervous systems, with particular focus on diaphragm activity, ventilation efficiency, haemodynamics, heart rate variability, cardiorespiratory coupling, respiratory sinus arrhythmia and sympathovagal balance. The review ends with a brief discussion of the potential clinical implications of slow breathing techniques. This is a topic that warrants further research, understanding and discussion. Key points Slow breathing practices have gained popularity in the western world due to their claimed health benefits, yet remain relatively untouched by the medical community. Investigations into the physiological effects of slow breathing have uncovered significant effects on the respiratory, cardiovascular, cardiorespiratory and autonomic nervous systems. Key findings include effects on respiratory muscle activity, ventilation efficiency, chemoreflex and baroreflex sensitivity, heart rate variability, blood flow dynamics, respiratory sinus arrhythmia, cardiorespiratory coupling, and sympathovagal balance. There appears to be potential for use of controlled slow breathing techniques as a means of optimising physiological parameters that appear to be associated with health and longevity, and that may extend to disease states; however, there is a dire need for further research into the area. Educational aims To provide

Supra-physiological folic acid concentrations induce aberrant DNA methylation in normal human cells in vitro.

PubMed

Charles, Michelle A; Johnson, Ian T; Belshaw, Nigel J

2012-07-01

The micronutrients folate and selenium may modulate DNA methylation patterns by affecting intracellular levels of the methyl donor S-adenosylmethionine (SAM) and/or the product of methylation reactions S-adenosylhomocysteine (SAH). WI-38 fibroblasts and FHC colon epithelial cells were cultured in the presence of two forms of folate or four forms of selenium at physiologically-relevant doses, and their effects on LINE-1 methylation, gene-specific CpG island (CGI) methylation and intracellular SAM:SAH were determined. At physiologically-relevant doses the forms of folate or selenium had no effect on LINE-1 or CGI methylation, nor on intracellular SAM:SAH. However the commercial cell culture media used for the selenium studies, containing supra-physiological concentrations of folic acid, induced LINE-1 hypomethylation, CGI hypermethylation and decreased intracellular SAM:SAH in both cell lines. We conclude that the exposure of normal human cells to supra-physiological folic acid concentrations present in commercial cell culture media perturbs the intracellular SAM:SAH ratio and induces aberrant DNA methylation.

Mutation of von Hippel–Lindau Tumour Suppressor and Human Cardiopulmonary Physiology

PubMed Central

Smith, Thomas G; Brooks, Jerome T; Balanos, George M; Lappin, Terence R; Layton, D. Mark; Leedham, Dawn L; Liu, Chun; Maxwell, Patrick H; McMullin, Mary F; McNamara, Christopher J; Percy, Melanie J; Pugh, Christopher W; Ratcliffe, Peter J; Talbot, Nick P; Treacy, Marilyn; Robbins, Peter A

2006-01-01

Background The von Hippel–Lindau tumour suppressor protein–hypoxia-inducible factor (VHL–HIF) pathway has attracted widespread medical interest as a transcriptional system controlling cellular responses to hypoxia, yet insights into its role in systemic human physiology remain limited. Chuvash polycythaemia has recently been defined as a new form of VHL-associated disease, distinct from the classical VHL-associated inherited cancer syndrome, in which germline homozygosity for a hypomorphic VHL allele causes a generalised abnormality in VHL–HIF signalling. Affected individuals thus provide a unique opportunity to explore the integrative physiology of this signalling pathway. This study investigated patients with Chuvash polycythaemia in order to analyse the role of the VHL–HIF pathway in systemic human cardiopulmonary physiology. Methods and Findings Twelve participants, three with Chuvash polycythaemia and nine controls, were studied at baseline and during hypoxia. Participants breathed through a mouthpiece, and pulmonary ventilation was measured while pulmonary vascular tone was assessed echocardiographically. Individuals with Chuvash polycythaemia were found to have striking abnormalities in respiratory and pulmonary vascular regulation. Basal ventilation and pulmonary vascular tone were elevated, and ventilatory, pulmonary vasoconstrictive, and heart rate responses to acute hypoxia were greatly increased. Conclusions The features observed in this small group of patients with Chuvash polycythaemia are highly characteristic of those associated with acclimatisation to the hypoxia of high altitude. More generally, the phenotype associated with Chuvash polycythaemia demonstrates that VHL plays a major role in the underlying calibration and homeostasis of the respiratory and cardiovascular systems, most likely through its central role in the regulation of HIF. PMID:16768548

Interaction of Salinity and CaCO3 Affects the Physiology and Fatty Acid Metabolism in Portulaca oleracea.

PubMed

Bessrour, Mouna; Chelbi, Najla; Moreno, Diego A; Chibani, Farhat; Abdelly, Chedly; Carvajal, Micaela

2018-06-25

As a result of the extreme conditions that usually occur in Mediterranean climates, the objective of this work is to study the combined and/or separate effects of saline and alkaline stresses in Portulaca oleracea. The study was carried out to determine the nutritional food potential in relation to plant physiological parameters. The results show that alkaline media in which CaCO 3 was present did not affect growth but exposure to 100 mM NaCl decreased it greatly. Fatty acid content increased under all stress conditions but to a higher extent with salinity; however, the protein content was increased only by alkaline media. The beneficial effect of each stress on P. oleracea is discussed in light of the physiological response, pointing out the suitability of this plant for human nutrition.

Advancements in remote physiological measurement and applications in human-computer interaction

NASA Astrophysics Data System (ADS)

McDuff, Daniel

2017-04-01

Physiological signals are important for tracking health and emotional states. Imaging photoplethysmography (iPPG) is a set of techniques for remotely recovering cardio-pulmonary signals from video of the human body. Advances in iPPG methods over the past decade combined with the ubiquity of digital cameras presents the possibility for many new, lowcost applications of physiological monitoring. This talk will highlight methods for recovering physiological signals, work characterizing the impact of video parameters and hardware on these measurements, and applications of this technology in human-computer interfaces.

Human Physiological Responses to Acute and Chronic Cold Exposure

NASA Technical Reports Server (NTRS)

Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

2001-01-01

When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

Low physiological levels of prostaglandins E2 and F2α improve human sperm functions.

PubMed

Rios, Mariana; Carreño, Daniela V; Oses, Carolina; Barrera, Nelson; Kerr, Bredford; Villalón, Manuel

2016-03-01

Prostaglandins (PGs) have been reported to be present in the seminal fluid and cervical mucus, affecting different stages of sperm maturation from spermatogenesis to the acrosome reaction. This study assessed the effects of low physiological PGE2 and PGF2α concentrations on human sperm motility and on the ability of the spermatozoa to bind to the zona pellucida (ZP). Human spermatozoa were isolated from seminal samples with normal concentration and motility parameters and incubated with 1μM PGE2, 1μM PGF2α or control solution to determine sperm motility and the ability to bind to human ZP. The effects of both PGs on intracellular calcium levels were determined. Incubation for 2 or 18h with PGE2 or PGF2α resulted in a significant (P<0.05) increase in the percentage of spermatozoa with progressive motility. In contrast with PGF2α, PGE2 alone induced an increase in sperm intracellular calcium levels; however, the percentage of sperm bound to the human ZP was doubled for both PGs. These results indicate that incubation of human spermatozoa with low physiological levels of PGE2 or PGF2α increases sperm functions and could improve conditions for assisted reproduction protocols.

Lead remediation and changes in human lead exposure: some physiological and biokinetic dimensions.

PubMed

Mushak, Paul

2003-02-15

This paper presents a qualitative and quantitative analysis of the various aspects of lead remediation effectiveness with particular reference to human health risk assessment. One of the key elements of lead remediation efforts at such sites as those under the Superfund program deals with populations at elevated exposure and toxicity risk in the proximity of, or at, the site of remediation, especially remediation workers, workers at other tasks on sites that were remediated down to some action level of lead concentration in soils, and groups at risk in nearby communities. A second element has to do with how one measures or models lead exposure changes with special reference to baseline and post-remediation conditions. Various biomarkers of lead exposure can be employed, but their use requires detailed knowledge of what results using each means. The most commonly used approach is measurement of blood lead (Pb-B). Recognized limitations in the use of Pb-B has led to the use of predictive Pb exposure models, which are less vulnerable to the many behavioral, physiological, and environmental parameters that can distort isolated or 'single shot' Pb-B testings. A third aspect covered in this paper presents various physiological factors that affect the methods by which one evaluates Pb remediation effectiveness. Finally, this article offers an integrated look at how lead remediation actions directed at one lead source or pathway affect the total lead exposure picture for human populations at elevated lead exposure and toxicity risk.

Sunspot Dynamics Are Reflected in Human Physiology and Pathophysiology

NASA Astrophysics Data System (ADS)

Hrushesky, William J. M.; Sothern, Robert B.; Du-Quiton, Jovelyn; Quiton, Dinah Faith T.; Rietveld, Wop; Boon, Mathilde E.

2011-03-01

Periodic episodes of increased sunspot activity (solar electromagnetic storms) occur with 10-11 and 5-6 year periodicities and may be associated with measurable biological events. We investigated whether this sunspot periodicity characterized the incidence of Pap smear-determined cervical epithelial histopathologies and human physiologic functions. From January 1983 through December 2003, monthly averages were obtained for solar flux and sunspot numbers; six infectious, premalignant and malignant changes in the cervical epithelium from 1,182,421 consecutive, serially independent, screening Pap smears (59°9"N, 4°29"E); and six human physiologic functions of a healthy man (oral temperature, pulse, systolic and diastolic blood pressure, respiration, and peak expiratory flow), which were measured ∼5 times daily during ∼34,500 self-measurement sessions (44°56"N, 93°8"W). After determining that sunspot numbers and solar flux, which were not annually rhythmic, occurred with a prominent 10-year and a less-prominent 5.75-year periodicity during this 21-year study span, each biological data set was analyzed with the same curve-fitting procedures. All six annually rhythmic Pap smear-detected infectious, premalignant and malignant cervical epithelial pathologies showed strong 10-year and weaker 5.75-year cycles, as did all six self-measured, annually rhythmic, physiologic functions. The phases (maxima) for the six histopathologic findings and five of six physiologic measurements were very near, or within, the first two quarters following the 10-year solar maxima. These findings add to the growing evidence that solar magnetic storm periodicities are mirrored by cyclic phase-locked rhythms of similar period length or lengths in human physiology and pathophysiology.

Drawing on student knowledge in human anatomy and physiology

NASA Astrophysics Data System (ADS)

Slominski, Tara Nicole

Prior to instruction, students may have developed alternative conceptions about the mechanics behind human physiology. To help students re-shape these ideas into correct reasoning, the faulty characteristics reinforcing the alternative conceptions need to made explicit. This study used student-generated drawings to expose alternative conceptions Human Anatomy and Physiology students had prior to instruction on neuron physiology. Specifically, we investigated how students thought about neuron communication across a synapse (n=355) and how neuron activity can be modified (n=311). When asked to depict basic communication between two neurons, at least 80% of students demonstrated incorrect ideas about synaptic transmission. When targeting spatial and temporal summation, only eleven students (3.5%) were able to accurately depict at least one form of summation. In response to both drawing questions, student drawings revealed multiple alternative conceptions that resulted in a deeper analysis and characterization of the wide variation of student ideas.

Restless roosts: Light pollution affects behavior, sleep, and physiology in a free-living songbird.

PubMed

Ouyang, Jenny Q; de Jong, Maaike; van Grunsven, Roy H A; Matson, Kevin D; Haussmann, Mark F; Meerlo, Peter; Visser, Marcel E; Spoelstra, Kamiel

2017-11-01

The natural nighttime environment is increasingly polluted by artificial light. Several studies have linked artificial light at night to negative impacts on human health. In free-living animals, light pollution is associated with changes in circadian, reproductive, and social behavior, but whether these animals also suffer from physiologic costs remains unknown. To fill this gap, we made use of a unique network of field sites which are either completely unlit (control), or are artificially illuminated with white, green, or red light. We monitored nighttime activity of adult great tits, Parus major, and related this activity to within-individual changes in physiologic indices. Because altered nighttime activity as a result of light pollution may affect health and well-being, we measured oxalic acid concentrations as a biomarker for sleep restriction, acute phase protein concentrations and malaria infection as indices of immune function, and telomere lengths as an overall measure of metabolic costs. Compared to other treatments, individuals roosting in the white light were much more active at night. In these individuals, oxalic acid decreased over the course of the study. We also found that individuals roosting in the white light treatment had a higher probability of malaria infection. Our results indicate that white light at night increases nighttime activity levels and sleep debt and affects disease dynamics in a free-living songbird. Our study offers the first evidence of detrimental effects of light pollution on the health of free-ranging wild animals. © 2017 John Wiley & Sons Ltd.

Singularity now: using the ventricular assist device as a model for future human-robotic physiology.

PubMed

Martin, Archer K

2016-04-01

In our 21 st century world, human-robotic interactions are far more complicated than Asimov predicted in 1942. The future of human-robotic interactions includes human-robotic machine hybrids with an integrated physiology, working together to achieve an enhanced level of baseline human physiological performance. This achievement can be described as a biological Singularity. I argue that this time of Singularity cannot be met by current biological technologies, and that human-robotic physiology must be integrated for the Singularity to occur. In order to conquer the challenges we face regarding human-robotic physiology, we first need to identify a working model in today's world. Once identified, this model can form the basis for the study, creation, expansion, and optimization of human-robotic hybrid physiology. In this paper, I present and defend the line of argument that currently this kind of model (proposed to be named "IshBot") can best be studied in ventricular assist devices - VAD.

Singularity now: using the ventricular assist device as a model for future human-robotic physiology

PubMed Central

Martin, Archer K.

2016-01-01

In our 21st century world, human-robotic interactions are far more complicated than Asimov predicted in 1942. The future of human-robotic interactions includes human-robotic machine hybrids with an integrated physiology, working together to achieve an enhanced level of baseline human physiological performance. This achievement can be described as a biological Singularity. I argue that this time of Singularity cannot be met by current biological technologies, and that human-robotic physiology must be integrated for the Singularity to occur. In order to conquer the challenges we face regarding human-robotic physiology, we first need to identify a working model in today’s world. Once identified, this model can form the basis for the study, creation, expansion, and optimization of human-robotic hybrid physiology. In this paper, I present and defend the line of argument that currently this kind of model (proposed to be named “IshBot”) can best be studied in ventricular assist devices – VAD. PMID:28913480

Sunspot Dynamics Are Reflected in Human Physiology and Pathophysiology

PubMed Central

Sothern, Robert B.; Du-Quiton, Jovelyn; Quiton, Dinah Faith T.; Rietveld, Wop; Boon, Mathilde E.

2011-01-01

Abstract Periodic episodes of increased sunspot activity (solar electromagnetic storms) occur with 10–11 and 5–6 year periodicities and may be associated with measurable biological events. We investigated whether this sunspot periodicity characterized the incidence of Pap smear-determined cervical epithelial histopathologies and human physiologic functions. From January 1983 through December 2003, monthly averages were obtained for solar flux and sunspot numbers; six infectious, premalignant and malignant changes in the cervical epithelium from 1,182,421 consecutive, serially independent, screening Pap smears (59°9″N, 4°29″E); and six human physiologic functions of a healthy man (oral temperature, pulse, systolic and diastolic blood pressure, respiration, and peak expiratory flow), which were measured ∼5 times daily during ∼34,500 self-measurement sessions (44°56″N, 93°8″W). After determining that sunspot numbers and solar flux, which were not annually rhythmic, occurred with a prominent 10-year and a less-prominent 5.75-year periodicity during this 21-year study span, each biological data set was analyzed with the same curve-fitting procedures. All six annually rhythmic Pap smear-detected infectious, premalignant and malignant cervical epithelial pathologies showed strong 10-year and weaker 5.75-year cycles, as did all six self-measured, annually rhythmic, physiologic functions. The phases (maxima) for the six histopathologic findings and five of six physiologic measurements were very near, or within, the first two quarters following the 10-year solar maxima. These findings add to the growing evidence that solar magnetic storm periodicities are mirrored by cyclic phase-locked rhythms of similar period length or lengths in human physiology and pathophysiology. Key Words: Cervical infections—Cervical premalignancy—Geo-solar magnetic interactions—Pap smear—Schwabe cycle—10-year rhythm. Astrobiology 11, 93–103. PMID:21391821

Low-frequency sound affects active micromechanics in the human inner ear

PubMed Central

Kugler, Kathrin; Wiegrebe, Lutz; Grothe, Benedikt; Kössl, Manfred; Gürkov, Robert; Krause, Eike; Drexl, Markus

2014-01-01

Noise-induced hearing loss is one of the most common auditory pathologies, resulting from overstimulation of the human cochlea, an exquisitely sensitive micromechanical device. At very low frequencies (less than 250 Hz), however, the sensitivity of human hearing, and therefore the perceived loudness is poor. The perceived loudness is mediated by the inner hair cells of the cochlea which are driven very inadequately at low frequencies. To assess the impact of low-frequency (LF) sound, we exploited a by-product of the active amplification of sound outer hair cells (OHCs) perform, so-called spontaneous otoacoustic emissions. These are faint sounds produced by the inner ear that can be used to detect changes of cochlear physiology. We show that a short exposure to perceptually unobtrusive, LF sounds significantly affects OHCs: a 90 s, 80 dB(A) LF sound induced slow, concordant and positively correlated frequency and level oscillations of spontaneous otoacoustic emissions that lasted for about 2 min after LF sound offset. LF sounds, contrary to their unobtrusive perception, strongly stimulate the human cochlea and affect amplification processes in the most sensitive and important frequency range of human hearing. PMID:26064536

Human Physiology and the Environment in Health and Disease: Readings from Scientific American.

ERIC Educational Resources Information Center

1976

This anthology of articles is designed to supplement standard texts for courses in human physiology, environmental physiology, anatomy and physiology, pathobiology, general biology, and environmental medicine. It focuses on the influences of the external environment on the body, the physiological responses to environmental challenges, and the ways…

Molecular and physiological manifestations and measurement of aging in humans.

PubMed

Khan, Sadiya S; Singer, Benjamin D; Vaughan, Douglas E

2017-08-01

Biological aging is associated with a reduction in the reparative and regenerative potential in tissues and organs. This reduction manifests as a decreased physiological reserve in response to stress (termed homeostenosis) and a time-dependent failure of complex molecular mechanisms that cumulatively create disorder. Aging inevitably occurs with time in all organisms and emerges on a molecular, cellular, organ, and organismal level with genetic, epigenetic, and environmental modulators. Individuals with the same chronological age exhibit differential trajectories of age-related decline, and it follows that we should assess biological age distinctly from chronological age. In this review, we outline mechanisms of aging with attention to well-described molecular and cellular hallmarks and discuss physiological changes of aging at the organ-system level. We suggest methods to measure aging with attention to both molecular biology (e.g., telomere length and epigenetic marks) and physiological function (e.g., lung function and echocardiographic measurements). Finally, we propose a framework to integrate these molecular and physiological data into a composite score that measures biological aging in humans. Understanding the molecular and physiological phenomena that drive the complex and multifactorial processes underlying the variable pace of biological aging in humans will inform how researchers assess and investigate health and disease over the life course. This composite biological age score could be of use to researchers seeking to characterize normal, accelerated, and exceptionally successful aging as well as to assess the effect of interventions aimed at modulating human aging. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

The Virtual Physiological Human - a European initiative for in silico human modelling -.

PubMed

Viceconti, Marco; Clapworthy, Gordon; Van Sint Jan, Serge

2008-12-01

The Virtual Physiological Human (VPH) is an initiative, strongly supported by the European Commission (EC), that seeks to develop an integrated model of human physiology at multiple scales from the whole body through the organ, tissue, cell and molecular levels to the genomic level. VPH had its beginnings in 2005 with informal discussions amongst like-minded scientists which led to the STEP project, a Coordination Action funded by the EC that began in early 2006. The STEP project greatly accelerated the progress of the VPH and proved to be a catalyst for wide-ranging discussions within Europe and for outreach activities designed to develop a broad international approach to the huge scientific and technological challenges involved in this area. This paper provides an overview of the VPH and the developments it has engendered in the rapidly expanding worldwide activities associated with the physiome. It then uses one particular project, the Living Human Project, to illustrate the type of advances that are taking place to further the aims of the VPH and similar initiatives worldwide.

Physiological and hypoxic oxygen concentration differentially regulates human c-Kit+ cardiac stem cell proliferation and migration.

PubMed

Bellio, Michael A; Rodrigues, Claudia O; Landin, Ana Marie; Hatzistergos, Konstantinos E; Kuznetsov, Jeffim; Florea, Victoria; Valasaki, Krystalenia; Khan, Aisha; Hare, Joshua M; Schulman, Ivonne Hernandez

2016-12-01

Cardiac stem cells (CSCs) are being evaluated for their efficacy in the treatment of heart failure. However, numerous factors impair the exogenously delivered cells' regenerative capabilities. Hypoxia is one stress that contributes to inadequate tissue repair. Here, we tested the hypothesis that hypoxia impairs cell proliferation, survival, and migration of human CSCs relative to physiological and room air oxygen concentrations. Human endomyocardial biopsy-derived CSCs were isolated, selected for c-Kit expression, and expanded in vitro at room air (21% O 2 ). To assess the effect on proliferation, survival, and migration, CSCs were transferred to physiological (5%) or hypoxic (0.5%) O 2 concentrations. Physiological O 2 levels increased proliferation (P < 0.05) but did not affect survival of CSCs. Although similar growth rates were observed in room air and hypoxia, a significant reduction of β-galactosidase activity (-4,203 fluorescent units, P < 0.05), p16 protein expression (0.58-fold, P < 0.001), and mitochondrial content (0.18-fold, P < 0.001) in hypoxia suggests that transition from high (21%) to low (0.5%) O 2 reduces senescence and promotes quiescence. Furthermore, physiological O 2 levels increased migration (P < 0.05) compared with room air and hypoxia, and treatment with mesenchymal stem cell-conditioned media rescued CSC migration under hypoxia to levels comparable to physiological O 2 migration (2-fold, P < 0.05 relative to CSC media control). Our finding that physiological O 2 concentration is optimal for in vitro parameters of CSC biology suggests that standard room air may diminish cell regenerative potential. This study provides novel insights into the modulatory effects of O 2 concentration on CSC biology and has important implications for refining stem cell therapies. Copyright © 2016 the American Physiological Society.

Hair and Physiological Baldness

PubMed Central

Mercantini, Edward S.

1965-01-01

Human hair is one of the structures of the body about which little is generally known. Disease affecting the hair is often minimized or ignored by physicians because of lack of knowledge of this rudimentary organ. However, the patient's attitude toward hair loss is very different from the doctor's and he feels great concern about such loss. The development, growth and morphology of human hair are briefly presented. Experimental work which will increase our knowledge of hair growth and loss is reviewed. The various forms of physiological alopecia from birth onward are discussed, with special emphasis on the least-known type of physiological baldness, “male-pattern baldness” in the adult female. PMID:14312445

Research on human physiological parameters intelligent clothing based on distributed Fiber Bragg Grating

NASA Astrophysics Data System (ADS)

Miao, Changyun; Shi, Boya; Li, Hongqiang

2008-12-01

A human physiological parameters intelligent clothing is researched with FBG sensor technology. In this paper, the principles and methods of measuring human physiological parameters including body temperature and heart rate in intelligent clothing with distributed FBG are studied, the mathematical models of human physiological parameters measurement are built; the processing method of body temperature and heart rate detection signals is presented; human physiological parameters detection module is designed, the interference signals are filtered out, and the measurement accuracy is improved; the integration of the intelligent clothing is given. The intelligent clothing can implement real-time measurement, processing, storage and output of body temperature and heart rate. It has accurate measurement, portability, low cost, real-time monitoring, and other advantages. The intelligent clothing can realize the non-contact monitoring between doctors and patients, timely find the diseases such as cancer and infectious diseases, and make patients get timely treatment. It has great significance and value for ensuring the health of the elders and the children with language dysfunction.

Evolutionary change in physiological phenotypes along the human lineage

PubMed Central

Vining, Alexander Q.; Nunn, Charles L.

2016-01-01

Background and Objectives: Research in evolutionary medicine provides many examples of how evolution has shaped human susceptibility to disease. Traits undergoing rapid evolutionary change may result in associated costs or reduce the energy available to other traits. We hypothesize that humans have experienced more such changes than other primates as a result of major evolutionary change along the human lineage. We investigated 41 physiological traits across 50 primate species to identify traits that have undergone marked evolutionary change along the human lineage. Methodology: We analysed the data using two Bayesian phylogenetic comparative methods. One approach models trait covariation in non-human primates and predicts human phenotypes to identify whether humans are evolutionary outliers. The other approach models adaptive shifts under an Ornstein-Uhlenbeck model of evolution to assess whether inferred shifts are more common on the human branch than on other primate lineages. Results: We identified four traits with strong evidence for an evolutionary increase on the human lineage (amylase, haematocrit, phosphorus and monocytes) and one trait with strong evidence for decrease (neutrophilic bands). Humans exhibited more cases of distinct evolutionary change than other primates. Conclusions and Implications: Human physiology has undergone increased evolutionary change compared to other primates. Long distance running may have contributed to increases in haematocrit and mean corpuscular haemoglobin concentration, while dietary changes are likely related to increases in amylase. In accordance with the pathogen load hypothesis, human monocyte levels were increased, but many other immune-related measures were not. Determining the mechanisms underlying conspicuous evolutionary change in these traits may provide new insights into human disease. PMID:27615376

Evolutionary change in physiological phenotypes along the human lineage.

PubMed

Vining, Alexander Q; Nunn, Charles L

2016-01-01

Research in evolutionary medicine provides many examples of how evolution has shaped human susceptibility to disease. Traits undergoing rapid evolutionary change may result in associated costs or reduce the energy available to other traits. We hypothesize that humans have experienced more such changes than other primates as a result of major evolutionary change along the human lineage. We investigated 41 physiological traits across 50 primate species to identify traits that have undergone marked evolutionary change along the human lineage. We analysed the data using two Bayesian phylogenetic comparative methods. One approach models trait covariation in non-human primates and predicts human phenotypes to identify whether humans are evolutionary outliers. The other approach models adaptive shifts under an Ornstein-Uhlenbeck model of evolution to assess whether inferred shifts are more common on the human branch than on other primate lineages. We identified four traits with strong evidence for an evolutionary increase on the human lineage (amylase, haematocrit, phosphorus and monocytes) and one trait with strong evidence for decrease (neutrophilic bands). Humans exhibited more cases of distinct evolutionary change than other primates. Human physiology has undergone increased evolutionary change compared to other primates. Long distance running may have contributed to increases in haematocrit and mean corpuscular haemoglobin concentration, while dietary changes are likely related to increases in amylase. In accordance with the pathogen load hypothesis, human monocyte levels were increased, but many other immune-related measures were not. Determining the mechanisms underlying conspicuous evolutionary change in these traits may provide new insights into human disease. The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Nutrition and human physiological adaptations to space flight

NASA Technical Reports Server (NTRS)

Lane, H. W.; LeBlanc, A. D.; Putcha, L.; Whitson, P. A.

1993-01-01

Space flight provides a model for the study of healthy individuals undergoing unique stresses. This review focuses on how physiological adaptations to weightlessness may affect nutrient and food requirements in space. These adaptations include reductions in body water and plasma volume, which affect the renal and cardiovascular systems and thereby fluid and electrolyte requirements. Changes in muscle mass and function may affect requirements for energy, protein and amino acids. Changes in bone mass lead to increased urinary calcium concentrations, which may increase the risk of forming renal stones. Space motion sickness may influence putative changes in gastro-intestinal-hepatic function; neurosensory alterations may affect smell and taste. Some or all of these effects may be ameliorated through the use of specially designed dietary countermeasures.

Physiological correlates and emotional specificity of human piloerection

PubMed Central

Benedek, Mathias; Kaernbach, Christian

2011-01-01

Piloerection is known as an indicator of strong emotional experiences. However, little is known about the physiological and emotional specificity of this psychophysiological response. In the presented study, piloerection was elicited by audio stimuli taken from music and film episodes. The physiological response accompanying the incidence of piloerection was recorded with respect to electrodermal, cardiovascular and respiratory measures and compared to a matched control condition. The employment of an optical recording system allowed for a direct and objective assessment of visible piloerection. The occurrence of piloerection was primarily accompanied by an increase of phasic electrodermal activity and increased respiration depth as compared to a matched control condition. This physiological response pattern is discussed in the context of dominant theories of human piloerection. Consideration of all available evidence suggests that emotional piloerection represents a valuable indicator of the state of being moved or touched. PMID:21276827

Molecular physiology of weight regulation in mice and humans

PubMed Central

Leibel, RL

2009-01-01

Evolutionary considerations relating to efficiency in reproduction, and survival in hostile environments, suggest that body energy stores are sensed and actively regulated, with stronger physiological and behavioral responses to loss than gain of stored energy. Many physiological studies support this inference, and suggest that a critical axis runs between body fat and the hypothalamus. The molecular cloning of leptin and its receptor—projects based explicitly on the search for elements in this axis—confirmed the existence of this axis and provided important tools with which to understand its molecular physiology. Demonstration of the importance of this soma-brain reciprocal connection in body weight regulation in humans has been pursued using both classical genetic approaches and studies of physiological responses to experimental weight perturbation. This paper reviews the history of the rationale and methodology of the cloning of leptin (Lep) and the leptin receptor (Lepr), and describes some of the clinical investigation characterizing this axis. PMID:19136999

Affective temperament and personal identity.

PubMed

Stanghellini, Giovanni; Rosfort, René

2010-10-01

The complex relationship between temperament and personal identity, and between these and mental disorders, is of critical interest to both philosophy and psychopathology. More than other living creatures, human beings are constituted and characterized by the interplay of their genotype and phenotype. There appears to be an explanatory gap between the almost perfect genetic identity and the individual differences among humans. One reason for this gap is that a human being is a person besides a physiological organism. We propose an outline of a theoretical model that might somewhat mitigate the explanatory discrepancies between physiological mechanisms and individual human emotional experience and behaviour. Arguing for the pervasive nature of human affectivity, i.e., for the assumption that human consciousness and behaviour is characterised by being permeated by affectivity; to envisage the dynamics of emotional experience, we make use of a three-levelled model of human personal identity that differentiates between factors that are simultaneously at work in the constitution of the individual human person: 1) core emotions, 2) affective temperament types/affective character traits, and 3) personhood. These levels are investigated separately in order to respect the methodological diversity among them (neuroscience, psychopathology, and philosophy), but they are eventually brought together in a hermeneutical account of human personhood. Copyright 2010 Elsevier B.V. All rights reserved.

Leptin in human physiology and pathophysiology

PubMed Central

Magkos, Faidon; Brinkoetter, Mary; Sienkiewicz, Elizabeth; Dardeno, Tina A.; Kim, Sang-Yong; Hamnvik, Ole-Petter R.; Koniaris, Anastasia

2011-01-01

Leptin, discovered through positional cloning 15 years ago, is an adipocyte-secreted hormone with pleiotropic effects in the physiology and pathophysiology of energy homeostasis, endocrinology, and metabolism. Studies in vitro and in animal models highlight the potential for leptin to regulate a number of physiological functions. Available evidence from human studies indicates that leptin has a mainly permissive role, with leptin administration being effective in states of leptin deficiency, less effective in states of leptin adequacy, and largely ineffective in states of leptin excess. Results from interventional studies in humans demonstrate that leptin administration in subjects with congenital complete leptin deficiency or subjects with partial leptin deficiency (subjects with lipoatrophy, congenital or related to HIV infection, and women with hypothalamic amenorrhea) reverses the energy homeostasis and neuroendocrine and metabolic abnormalities associated with these conditions. More specifically, in women with hypothalamic amenorrhea, leptin helps restore abnormalities in hypothalamic-pituitary-peripheral axes including the gonadal, thyroid, growth hormone, and to a lesser extent adrenal axes. Furthermore, leptin results in resumption of menses in the majority of these subjects and, in the long term, may increase bone mineral content and density, especially at the lumbar spine. In patients with congenital or HIV-related lipoatrophy, leptin treatment is also associated with improvements in insulin sensitivity and lipid profile, concomitant with reduced visceral and ectopic fat deposition. In contrast, leptin's effects are largely absent in the obese hyperleptinemic state, probably due to leptin resistance or tolerance. Hence, another emerging area of research pertains to the discovery and/or usefulness of leptin sensitizers. Results from ongoing studies are expected to further increase our understanding of the role of leptin and the potential clinical

Physiological correlates and emotional specificity of human piloerection.

PubMed

Benedek, Mathias; Kaernbach, Christian

2011-03-01

Piloerection is known as an indicator of strong emotional experiences. However, little is known about the physiological and emotional specificity of this psychophysiological response. In the presented study, piloerection was elicited by audio stimuli taken from music and film episodes. The physiological response accompanying the incidence of piloerection was recorded with respect to electrodermal, cardiovascular and respiratory measures and compared to a matched control condition. The employment of an optical recording system allowed for a direct and objective assessment of visible piloerection. The occurrence of piloerection was primarily accompanied by an increase of phasic electrodermal activity and increased respiration depth as compared to a matched control condition. This physiological response pattern is discussed in the context of dominant theories of human piloerection. Consideration of all available evidence suggests that emotional piloerection represents a valuable indicator of the state of being moved or touched. Copyright © 2011 Elsevier B.V. All rights reserved.

Predation risk affects reproductive physiology and demography of elk.

PubMed

Creel, Scott; Christianson, David; Liley, Stewart; Winnie, John A

2007-02-16

Elk (Cervus elaphus) in the Greater Yellowstone Ecosystem alter patterns of aggregation, habitat selection, vigilance, and foraging in the presence of wolves (Canis lupus). Antipredator behaviors like these can reduce predation risk but are also likely to carry costs. Data from five elk populations studied for 16 site years showed that progesterone concentrations (from 1489 fecal samples) declined with the ratio of elk to wolves. In turn, progesterone concentrations were a good predictor of calf recruitment in the subsequent year. Together, these data suggest that wolves indirectly affect the reproductive physiology and the demography of elk through the costs of antipredator behavior.

Oxygen demand of perfused heart preparations: how electromechanical function and inadequate oxygenation affect physiology and optical measurements.

PubMed

Kuzmiak-Glancy, Sarah; Jaimes, Rafael; Wengrowski, Anastasia M; Kay, Matthew W

2015-06-01

What is the topic of this review? This review discusses how the function and electrophysiology of isolated perfused hearts are affected by oxygenation and energy utilization. The impact of oxygenation on fluorescence measurements in perfused hearts is also discussed. What advances does it highlight? Recent studies have illuminated the inherent differences in electromechanical function, energy utilization rate and oxygen requirements between the primary types of excised heart preparations. A summary and analysis of how these variables affect experimental results are necessary to elevate the physiological relevance of these approaches in order to advance the field of whole-heart research. The ex vivo perfused heart recreates important aspects of in vivo conditions to provide insight into whole-organ function. In this review we discuss multiple types of ex vivo heart preparations, explain how closely each mimic in vivo function, and discuss how changes in electromechanical function and inadequate oxygenation of ex vivo perfused hearts may affect measurements of physiology. Hearts that perform physiological work have high oxygen demand and are likely to experience hypoxia when perfused with a crystalloid perfusate. Adequate myocardial oxygenation is critically important for obtaining physiologically relevant measurements, so when designing experiments the type of ex vivo preparation and the capacity of perfusate to deliver oxygen must be carefully considered. When workload is low, such as during interventions that inhibit contraction, oxygen demand is also low, which could dramatically alter a physiological response to experimental variables. Changes in oxygenation also alter the optical properties of cardiac tissue, an effect that may influence optical signals measured from both endogenous and exogenous fluorophores. Careful consideration of oxygen supply, working condition, and wavelengths used to acquire optical signals is critical for obtaining physiologically

Triclosan and bisphenol a affect decidualization of human endometrial stromal cells.

PubMed

Forte, Maurizio; Mita, Luigi; Cobellis, Luigi; Merafina, Verdiana; Specchio, Raffaella; Rossi, Sergio; Mita, Damiano Gustavo; Mosca, Lavinia; Castaldi, Maria Antonietta; De Falco, Maria; Laforgia, Vincenza; Crispi, Stefania

2016-02-15

In recent years, impaired fertility and endometrium related diseases are increased. Many evidences suggest that environmental pollution might be considered a risk factor for endometrial physiopathology. Among environmental pollutants, endocrine disrupting chemicals (EDCs) act on endocrine system, causing hormonal imbalance which, in turn, leads to female and male reproductive dysfunctions. In this work, we studied the effects of triclosan (TCL) and bisphenol A (BPA), two widespread EDCs, on human endometrial stromal cells (ESCs), derived from endometrial biopsies from woman not affected by endometriosis. Cell proliferation, cell cycle, migration and decidualization mechanisms were investigated. Treatments have been performed with both the EDCs separately or in presence and in absence of progesterone used as decidualization stimulus. Both TCL and BPA did not affect cell proliferation, but they arrested ESCs at G2/M phase of cell cycle enhancing cell migration. TCL and BPA also increased gene expression and protein levels of some decidualization markers, such as insulin growth factor binding protein 1 (IGFBP1) and prolactin (PRL), amplifying the effect of progesterone alone. All together, our data strongly suggest that TCL and BPA might alter human endometrium physiology so affecting fertility and pregnancy outcome. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The human physiological impact of global deoxygenation.

PubMed

Martin, Daniel; McKenna, Helen; Livina, Valerie

2017-01-01

There has been a clear decline in the volume of oxygen in Earth's atmosphere over the past 20 years. Although the magnitude of this decrease appears small compared to the amount of oxygen in the atmosphere, it is difficult to predict how this process may evolve, due to the brevity of the collected records. A recently proposed model predicts a non-linear decay, which would result in an increasingly rapid fall-off in atmospheric oxygen concentration, with potentially devastating consequences for human health. We discuss the impact that global deoxygenation, over hundreds of generations, might have on human physiology. Exploring the changes between different native high-altitude populations provides a paradigm of how humans might tolerate worsening hypoxia over time. Using this model of atmospheric change, we predict that humans may continue to survive in an unprotected atmosphere for ~3600 years. Accordingly, without dramatic changes to the way in which we interact with our planet, humans may lose their dominance on Earth during the next few millennia.

Dunbar's number: group size and brain physiology in humans reexamined.

PubMed

de Ruiter, Jan; Weston, Gavin; Lyon, Stephen M

2011-01-01

Popular academic ideas linking physiological adaptations to social behaviors are spreading disconcertingly into wider societal contexts. In this article, we note our skepticism with one particularly popular—in our view, problematic—supposed causal correlation between neocortex size and social group size. The resulting Dunbar's Number, as it has come to be called, has been statistically tested against observed group size in different primate species. Although there may be reason to doubt the Dunbar's Number hypothesis among nonhuman primate species, we restrict ourselves here to the application of such an explanatory hypothesis to human, culture-manipulating populations. Human information process management, we argue, cannot be understood as a simple product of brain physiology. Cross-cultural comparison of not only group size but also relationship-reckoning systems like kinship terminologies suggests that although neocortices are undoubtedly crucial to human behavior, they cannot be given such primacy in explaining complex group composition, formation, or management.

Multi-sector thermo-physiological head simulator for headgear research

NASA Astrophysics Data System (ADS)

Martinez, Natividad; Psikuta, Agnes; Corberán, José Miguel; Rossi, René M.; Annaheim, Simon

2017-02-01

A novel thermo-physiological human head simulator for headgear testing was developed by coupling a thermal head manikin with a thermo-physiological model. As the heat flux at head-site is directly measured by the head manikin, this method provides a realistic quantification of the heat transfer phenomena occurring in the headgear, such as moisture absorption-desorption cycles, condensation, or moisture migration across clothing layers. Before coupling, the opportunities of the head manikin for representing the human physiology were evaluated separately. The evaluation revealed reduced precision in forehead and face temperature predictions under extreme heterogeneous temperature distributions and no initial limitation for simulating temperature changes observed in the human physiology. The thermo-physiological model predicted higher sweat rates when applied for coupled than for pure virtual simulations. After coupling, the thermo-physiological human head simulator was validated using eight human experiments. It precisely predicted core, mean skin, and forehead temperatures with average rmsd values within the average experimental standard deviation (rmsd of 0.20 ± 0.15, 0.83 ± 0.34, and 1.04 ± 0.54 °C, respectively). However, in case of forehead, precision was lower for the exposures including activity than for the sedentary exposures. The representation of the human sweat evaporation could be affected by a reduced evaporation efficiency and the manikin sweat dynamics. The industry will benefit from this thermo-physiological human head simulator leading to the development of helmet designs with enhanced thermal comfort and, therefore, with higher acceptance by users.

Multi-sector thermo-physiological head simulator for headgear research.

PubMed

Martinez, Natividad; Psikuta, Agnes; Corberán, José Miguel; Rossi, René M; Annaheim, Simon

2017-02-01

A novel thermo-physiological human head simulator for headgear testing was developed by coupling a thermal head manikin with a thermo-physiological model. As the heat flux at head-site is directly measured by the head manikin, this method provides a realistic quantification of the heat transfer phenomena occurring in the headgear, such as moisture absorption-desorption cycles, condensation, or moisture migration across clothing layers. Before coupling, the opportunities of the head manikin for representing the human physiology were evaluated separately. The evaluation revealed reduced precision in forehead and face temperature predictions under extreme heterogeneous temperature distributions and no initial limitation for simulating temperature changes observed in the human physiology. The thermo-physiological model predicted higher sweat rates when applied for coupled than for pure virtual simulations. After coupling, the thermo-physiological human head simulator was validated using eight human experiments. It precisely predicted core, mean skin, and forehead temperatures with average rmsd values within the average experimental standard deviation (rmsd of 0.20 ± 0.15, 0.83 ± 0.34, and 1.04 ± 0.54 °C, respectively). However, in case of forehead, precision was lower for the exposures including activity than for the sedentary exposures. The representation of the human sweat evaporation could be affected by a reduced evaporation efficiency and the manikin sweat dynamics. The industry will benefit from this thermo-physiological human head simulator leading to the development of helmet designs with enhanced thermal comfort and, therefore, with higher acceptance by users.

Using Noninvasive Wearable Computers to Recognize Human Emotions from Physiological Signals

NASA Astrophysics Data System (ADS)

Lisetti, Christine Lætitia; Nasoz, Fatma

2004-12-01

We discuss the strong relationship between affect and cognition and the importance of emotions in multimodal human computer interaction (HCI) and user modeling. We introduce the overall paradigm for our multimodal system that aims at recognizing its users' emotions and at responding to them accordingly depending upon the current context or application. We then describe the design of the emotion elicitation experiment we conducted by collecting, via wearable computers, physiological signals from the autonomic nervous system (galvanic skin response, heart rate, temperature) and mapping them to certain emotions (sadness, anger, fear, surprise, frustration, and amusement). We show the results of three different supervised learning algorithms that categorize these collected signals in terms of emotions, and generalize their learning to recognize emotions from new collections of signals. We finally discuss possible broader impact and potential applications of emotion recognition for multimodal intelligent systems.

Physiological Arousal and Juvenile Psychopathy: Is Low Resting Heart Rate Associated With Affective Dimensions?

PubMed Central

Kavish, Nicholas; Vaughn, Michael G.; Cho, Eunsoo; Barth, Amy; Boutwell, Brian; Vaughn, Sharon; Capin, Philip; Stillman, Stephanie; Martinez, Leticia

2016-01-01

A wealth of past research has examined the relationship between low physiological arousal and violence or antisocial behavior. Relatively little research; however, has examined the relationship between low physiological arousal and psychopathic traits, with even less having been conducted with juveniles. The current study attempts to fill this gap by evaluating juveniles’ physiological arousal using resting heart rate and their levels of psychopathic traits. Results suggest that there is indeed an inverse relationship between resting heart rate and the affective traits of psychopathy (Uncaring, Callousness, and Unemotionality) as well as Thrill or Sensation Seeking in males. No significant relationship was found in females. Implications of the findings as well as study limitations and future directions are discussed. PMID:27160003

Physiological correlates of stress-induced decrements in human perceptual performance.

DOT National Transportation Integrated Search

1993-11-01

Stress-induced changes in human performance have been thought to result from alterations in the "multidimensional arousal state" of the individual, as indexed by alterations in the physiological and psychological mechanisms controlling performance. I...

Modeling Physiological Systems in the Human Body as Networks of Quasi-1D Fluid Flows

NASA Astrophysics Data System (ADS)

Staples, Anne

2008-11-01

Extensive research has been done on modeling human physiology. Most of this work has been aimed at developing detailed, three-dimensional models of specific components of physiological systems, such as a cell, a vein, a molecule, or a heart valve. While efforts such as these are invaluable to our understanding of human biology, if we were to construct a global model of human physiology with this level of detail, computing even a nanosecond in this computational being's life would certainly be prohibitively expensive. With this in mind, we derive the Pulsed Flow Equations, a set of coupled one-dimensional partial differential equations, specifically designed to capture two-dimensional viscous, transport, and other effects, and aimed at providing accurate and fast-to-compute global models for physiological systems represented as networks of quasi one-dimensional fluid flows. Our goal is to be able to perform faster-than-real time simulations of global processes in the human body on desktop computers.

Physiological aspects of human milk lipids.

PubMed

Koletzko, B; Rodriguez-Palmero, M; Demmelmair, H; Fidler, N; Jensen, R; Sauerwald, T

2001-11-01

Human milk from healthy and well-nourished mothers is the preferred form of feeding for all healthy newborn infants. The nutrient supply with human milk supports normal growth and development of the infant. Here the general characteristics of human milk lipids and recent knowledge on lactational physiology, composition and functional aspects of human milk lipids are discussed. Lipids in human milk represent the main source of energy for the breastfed baby and supply essential nutrients such as fat-soluble vitamins and polyunsaturated fatty acids (PUFA). The essential fatty acids linoleic and alpha-linolenic acids (LA and ALA) are precursors of long-chain polyunsaturated fatty acids (LC-PUFA), including arachidonic (20:4n-6) and docosahexaenoic (22:6n-3) acids (AA and DHA). LC-PUFA serve as indispensable structural components of cellular membranes and are deposited to a considerable extent in the growing brain and the retina during perinatal development. The supply of preformed LC-PUFA with human milk lipids has been related to functional outcomes of the recipient infants such as visual acuity and development of cognitive functions during the first year of life. Recent stable isotope studies indicate that the major portion of milk PUFA is not derived directly from the maternal diet, but stems from endogenous body stores. Thus, not only the woman's current but also her long-term dietary intake is of marked relevance for milk fat composition.

Study of physiological responses to acute carbon monoxide exposure with a human patient simulator.

PubMed

Cesari, Whitney A; Caruso, Dominique M; Zyka, Enela L; Schroff, Stuart T; Evans, Charles H; Hyatt, Jon-Philippe K

2006-12-01

Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design, conduct, and present (orally and in written form) their project testing physiological adaptation to an extreme environment. This article is a student report on the physiological response to acute carbon monoxide exposure in a simulated healthy adult male and a coal miner and represents how 1) human patient simulators can be used in a nonclinical way for experiential hypothesis testing; 2) students can transition from traditional textbook learning to practical application of their knowledge; and 3) student-initiated group investigation drives critical thought. While the course instructors remain available for consultation throughout the project, the relatively unstructured framework of the assignment drives the students to create an experiment independently, troubleshoot problems, and interpret the results. The only stipulation of the project is that the students must generate an experiment that is physiologically realistic and that requires them to search out and incorporate appropriate data from primary scientific literature. In this context, the human patient simulator is a viable educational tool for teaching integrative physiology in a laboratory environment by bridging textual information with experiential investigation.

Positive affect, negative affect, and physiological hyperarousal among referred and nonreferred youths.

PubMed

Laurent, Jeff; Joiner, Thomas E; Catanzaro, Salvatore J

2011-12-01

The Positive and Negative Affect Scale for Children (PANAS-C) and the Physiological Hyperarousal Scale for Children (PH-C) seem ideal measures for school mental health screenings, because they are theory based, psychometrically sound, and brief. This study provides descriptive information and preliminary cutoff scores in an effort to increase the practical utility of the measures. Scores on the PANAS-C Positive Affect (PA) and Negative Affect (NA) scales and the PH-C were compared for a general sample of schoolchildren (n = 226), a group of students referred for special education services (n = 83), and youths on an inpatient psychiatric unit (n = 37). Expected patterns of scores emerged for the general school and referred school samples, although only scores on the PH-C were statistically significantly different. Differences in scores between the general school and inpatient samples were significant for all 3 scales. Differences in scores between the referred school and inpatient samples were significant for the NA scale and the PH-C but not for the PA scale. In addition, we used traditional self-report measures to form groups of normal, anxious, depressed, and mixed anxious and depressed youths. Again, predicted general patterns of PA, NA and PH scores were supported, although statistical differences were not always evident. In particular, scores on the PH-C for the anxious and depressed groups were inconsistent with predictions. Possible reasons related to sample and scale issues are discussed. Finally, preliminary cutoff scores were proposed for the PANAS-C scales and the PH-C.

Colonic Fermentation: A Neglected Topic in Human Physiology Education

ERIC Educational Resources Information Center

Valeur, Jorgen; Berstad, Arnold

2010-01-01

Human physiology textbooks tend to limit their discussion of colonic functions to those of absorbing water and electrolytes and storing waste material. However, the colon is a highly active metabolic organ, containing an exceedingly complex society of microbes. By means of fermentation, gastrointestinal microbes break down nutrients that cannot be…

PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL FOR HUMAN EXPOSURES TO METHYL TERTIARY-BUTYL ETHER

EPA Science Inventory

Humans can be exposed by inhalation, ingestion, or dermal absorption to methyl tertiary-butyl ether (MTBE), an oxygenated fuel additive, from contaminated water sources. The purpose of this research was to develop a physiologically based pharmacokinetic model describing in human...

EPM - The European Facility for human physiology research on ISS.

PubMed

Rieschel, Mats; Nasca, Rosario; Junk, Peter; Gerhard, Ingo

2002-07-01

The European Physiology Modules (EPM) Facility is one of the four major Space Station facilities being developed within the framework of ESA's Microgravity Facilities for Columbus (MFC) programme. In order to allow a wide spectrum of physiological studies in weightlessness conditions, the facility provides the infrastructure to accommodate a variable set of scientific equipment. The initial EPM configuration supports experiments in the fields of neuroscience, bone & muscle research, cardiovascular research and metabolism. The International Space Life Science Working Group (ISLSWG) has recommended co-locating EPM with the 2 NASA Human Research Facility racks.

Communalism Predicts Maternal Affect, Stress, and Physiology Better than Ethnicity and SES

PubMed Central

Abdou, Cleopatra M.; Schetter, Christine Dunkel; Campos, Belinda; Hilmert, Clayton J.; Dominguez, Tyan Parker; Hobel, Calvin J.; Glynn, Laura M.; Sandman, Curt

2010-01-01

The present study examined the relevance of communalism, operationalized as a cultural orientation emphasizing interdependence, to maternal prenatal emotional health and physiology and distinguished its effects from those of ethnicity and childhood and adult SES. African American and European American women (N=297) were recruited early in pregnancy and followed through 32 weeks gestation using interviews and medical chart review. Overall, African American women and women of lower socioeconomic backgrounds had higher levels of negative affect, stress and blood pressure, but these ethnic and socioeconomic disparities were not observed among women higher in communalism. Hierarchical multivariate regression analyses showed that communalism was a more robust predictor of prenatal emotional health than ethnicity, childhood SES, and adult SES. Communalism also interacted with ethnicity and SES, resulting in lower blood pressure during pregnancy for African American women and women who experienced socioeconomic disadvantage over the life course. The effects of communalism on prenatal affect, stress, and physiology were not explained by depressive symptoms at study entry, perceived availability of social support, self-esteem, optimism, mastery, nor pregnancy-specific factors, including whether the pregnancy was planned, desired after conception, or how frequently the woman felt happy to be pregnant. This suggests that a communal cultural orientation benefits maternal prenatal emotional health and physiology over and above its links to better-understood personal and social resources in addition to economic resources. Implications regarding culture as a determinant of maternal prenatal health and well-being and as a potentially important lens for examining ethnic and socioeconomic inequalities in health are discussed. PMID:20658883

Relationship Between Human Physiological Parameters And Geomagnetic Variations Of Solar Origin

NASA Astrophysics Data System (ADS)

Dimitrova, S.

This study attempts to assess the influence of increased geomagnetic activity on some human physiological parameters. The blood pressure, heart rate and general well-being of 86 volunteers were measured (the latter by means of a standardized questionnaire) on work days in autumn 2001 (01/10 to 09/11) and in spring 2002 (08/04 to 28/05). These periods were chosen because of maximal expected geomagnetic activity. Altogether, 2799 recordings were obtained and analysed. MANOVA was employed to check the significance of the influence of three factors on the physiological parameters under consideration. The three factors were the following: 1) planetary geomagnetic activity level estimated by Ap-index and divided into five levels; 2) gender - males and females; 3) blood pressure degree - persons in the group examined were divided into hypotensive, normotensive and hypertensive. Post hoc analysis was performed to elicit the significance of differences in the factors' levels. The average arterial blood pressure of the group was found to increase significantly with the increase of geomagnetic activity level. The average increment of systolic and diastolic blood pressure reached 9%, which deserves attention from a medical point of view. This effect was present irrespectively of gender. Results obtained suppose that hypertensive persons have the highest sensitivity and the hypotensive persons have the lowest sensitivity of the arterial blood pressure to increase of geomagnetic activity. The results did not show significant changes in the heart rate. The percentage of the persons who reported subjective psycho-physiological complaints was also found to increase significantly with the geomagnetic activity increase. During severe geomagnetic storms 30% of the persons examined reported subjective complaints and the highest sensitivity was revealed for the hypertensive females. The results obtained add further evidence that blood pressure seems to be affected by geomagnetic

Do targeted written comments and the rubric method of delivery affect performance on future human physiology laboratory reports?

PubMed

Clayton, Zachary S; Wilds, Gabriel P; Mangum, Joshua E; Hocker, Austin D; Dawson, Sierra M

2016-09-01

We investigated how students performed on weekly two-page laboratory reports based on whether the grading rubric was provided to the student electronically or in paper form and the inclusion of one- to two-sentence targeted comments. Subjects were registered for a 289-student, third-year human physiology class with laboratory and were randomized into four groups related to rubric delivery and targeted comments. All students received feedback via the same detailed grading rubric. At the end of the term, subjects provided consent and a self-assessment of their rubric viewing rate and preferences. There were no differences in laboratory report scores between groups (P = 0.86), although scores did improve over time (P < 0.01). Students receiving targeted comments self-reported viewing their rubric more often than students that received no comments (P = 0.02), but the viewing rate was independent of the rubric delivery method (P = 0.15). Subjects with high rubric viewing rates did not have higher laboratory report grades than subjects with low viewing rates (P = 0.64). When asked about their preference for the future, 43% of respondents preferred the same method again (electronic or paper rubric) and 25% had no preference. We conclude that although student laboratory report grades improved over time, the rate and degree of improvement were not related to rubric delivery method or to the inclusion of targeted comments. Copyright © 2016 The American Physiological Society.

The Role of Negative Affect and Physiological Regulation in maternal attribution

PubMed Central

Wang, Zhe; Deater-Deckard, Kirby; Bell, Martha Ann

2016-01-01

SYNOPSIS Objective Mothers who attribute child misbehaviors to children’s intentions, and not to situational causes, show more hostile parenting behaviors. Why are some mothers more likely than others to make more hostile attributions (i.e., high intentional attributions and low situational attributions) when confronted with child challenging behaviors? We examined the relation between mothers’ perception of child challenging behaviors and their hostile attributions of child misbehaviors, with an emphasis on how maternal negative affect and resting vagal activity moderated this relation. Design 160 mothers of 3- to 7-year-old children reported their perceptions of child problem behaviors, their attributions regarding child misbehaviors, and their temperamental negative affect. Mothers’ respiratory sinus arrhythmia (RSA) was measured during resting state. Results Maternal perceptions of child challenging behaviors were positively related to hostile maternal attributions, and this relation was strongest in mothers with high negative affect and low resting RSA. Conclusions These findings indicate the importance of considering mothers’ affective and physiological attributes when examining social-cognitive processes in parenting. PMID:27667969

Regulatory physiology discipline science plan

NASA Technical Reports Server (NTRS)

1991-01-01

The focus of the Regulatory Physiology discipline of the Space Physiology and Countermeasures Program is twofold. First, to determine and study how microgravity and associated factors of space flight affect the regulatory mechanisms by which humans adapt and achieve homeostasis and thereby regulate their ability to respond to internal and external signals; and, second, to study selected physiological systems that have been demonstrated to be influenced by gravity. The Regulatory Physiology discipline, as defined here, is composed of seven subdisciplines: (1) Circadian Rhythms, (2) Endocrinology, (3) Fluid and Electrolyte Regulation, (4) Hematology, (5) Immunology, (6) Metabolism and Nutrition, and (7) Temperature Regulation. The purpose of this Discipline Science Plan is to provide a conceptual strategy for NASA's Life Sciences Division research and development activities in the area of regulatory physiology. It covers the research areas critical to NASA's programmatic requirements for the Extended-Duration Orbiter, Space Station Freedom, and exploration mission science activities. These science activities include ground-based and flight; basic, applied, and operational; and animal and human research and development. This document summarizes the current status of the program, outlines available knowledge, establishes goals and objectives, identifies science priorities, and defines critical questions in regulatory physiology. It contains a general plan that will be used by both NASA Headquarters Program Offices and the field centers to review and plan basic, applied, and operational intramural and extramural research and development activities in this area.

Environmental and biological context modulates the physiological stress response of bats to human disturbance.

PubMed

Phelps, Kendra L; Kingston, Tigga

2018-06-01

Environmental and biological context play significant roles in modulating physiological stress responses of individuals in wildlife populations yet are often overlooked when evaluating consequences of human disturbance on individual health and fitness. Furthermore, most studies gauge individual stress responses based on a single physiological biomarker, typically circulating glucocorticoid concentrations, which limits interpretation of the complex, multifaceted responses of individuals to stressors. We selected four physiological biomarkers to capture short-term and prolonged stress responses in a widespread cave-roosting bat, Hipposideros diadema, across multiple gradients of human disturbance in and around caves in the Philippines. We used conditional inference trees and random forest analysis to determine the role of environmental quality (cave complexity, available roosting area), assemblage composition (intra- and interspecific associations and species richness), and intrinsic characteristics of individuals (sex and reproductive status) in modulating responses to disturbance. Direct cave disturbance (hunting pressure and human visitation) was the primary driver of neutrophil-to-lymphocyte ratios, with lower ratios associated with increased disturbance, while context-specific factors were more important in explaining total leukocyte count, body condition, and ectoparasite load. Moreover, conditional inference trees revealed complex interactions among human disturbance and modulating factors. Cave complexity often ameliorated individual responses to human disturbance, whereas conspecific abundance often compounded responses. Our study demonstrates the importance of an integrated approach that incorporates environmental and biological context when identifying drivers of physiological responses, and that assesses responses to gradients of direct and indirect disturbance using multiple complementary biomarkers.

Infrasound from Wind Turbines Could Affect Humans

ERIC Educational Resources Information Center

Salt, Alec N.; Kaltenbach, James A.

2011-01-01

Wind turbines generate low-frequency sounds that affect the ear. The ear is superficially similar to a microphone, converting mechanical sound waves into electrical signals, but does this by complex physiologic processes. Serious misconceptions about low-frequency sound and the ear have resulted from a failure to consider in detail how the ear…

Developing Physiologic Models for Emergency Medical Procedures Under Microgravity

NASA Technical Reports Server (NTRS)

Parker, Nigel; O'Quinn, Veronica

2012-01-01

Several technological enhancements have been made to METI's commercial Emergency Care Simulator (ECS) with regard to how microgravity affects human physiology. The ECS uses both a software-only lung simulation, and an integrated mannequin lung that uses a physical lung bag for creating chest excursions, and a digital simulation of lung mechanics and gas exchange. METI s patient simulators incorporate models of human physiology that simulate lung and chest wall mechanics, as well as pulmonary gas exchange. Microgravity affects how O2 and CO2 are exchanged in the lungs. Procedures were also developed to take into affect the Glasgow Coma Scale for determining levels of consciousness by varying the ECS eye-blinking function to partially indicate the level of consciousness of the patient. In addition, the ECS was modified to provide various levels of pulses from weak and thready to hyper-dynamic to assist in assessing patient conditions from the femoral, carotid, brachial, and pedal pulse locations.

Developing Physiologic Models for Emergency Medical Procedures Under Microgravity

NASA Technical Reports Server (NTRS)

Parker, Nigel; OQuinn, Veronica

2012-01-01

Several technological enhancements have been made to METI's commercial Emergency Care Simulator (ECS) with regard to how microgravity affects human physiology. The ECS uses both a software-only lung simulation, and an integrated mannequin lung that uses a physical lung bag for creating chest excursions, and a digital simulation of lung mechanics and gas exchange. METI's patient simulators incorporate models of human physiology that simulate lung and chest wall mechanics, as well as pulmonary gas exchange. Microgravity affects how O2 and CO2 are exchanged in the lungs. Procedures were also developed to take into affect the Glasgow Coma Scale for determining levels of consciousness by varying the ECS eye-blinking function to partially indicate the level of consciousness of the patient. In addition, the ECS was modified to provide various levels of pulses from weak and thready to hyper-dynamic to assist in assessing patient conditions from the femoral, carotid, brachial, and pedal pulse locations.

Macaque Cardiac Physiology Is Sensitive to the Valence of Passively Viewed Sensory Stimuli

PubMed Central

Bliss-Moreau, Eliza; Machado, Christopher J.; Amaral, David G.

2013-01-01

Autonomic nervous system activity is an important component of affective experience. We demonstrate in the rhesus monkey that both the sympathetic and parasympathetic branches of the autonomic nervous system respond differentially to the affective valence of passively viewed video stimuli. We recorded cardiac impedance and an electrocardiogram while adult macaques watched a series of 300 30-second videos that varied in their affective content. We found that sympathetic activity (as measured by cardiac pre-ejection period) increased and parasympathetic activity (as measured by respiratory sinus arrhythmia) decreased as video content changes from positive to negative. These findings parallel the relationship between autonomic nervous system responsivity and valence of stimuli in humans. Given the relationship between human cardiac physiology and affective processing, these findings suggest that macaque cardiac physiology may be an index of affect in nonverbal animals. PMID:23940712

Oxygen and differentiation status modulate the effect of X-ray irradiation on physiology and mitochondrial proteome of human neuroblastoma cells.

PubMed

Džinić, Tamara; Hartwig, Sonja; Lehr, Stefan; Dencher, Norbert A

2016-12-01

Cytotoxic effects, including oxidative stress, of low linear energy transfer (LET)-ionizing radiation are often underestimated and studies of their mechanisms using cell culture models are widely conducted with cells cultivated at atmospheric oxygen that does not match its physiological levels in body tissues. Also, cell differentiation status plays a role in the outcome of experiments. We compared effects of 2 Gy X-ray irradiation on the physiology and mitochondrial proteome of nondifferentiated and human neuroblastoma (SH-SY5Y) cells treated with retinoic acid cultivated at 21% and 5% O 2 . Irradiation did not affect the amount of subunits of OxPhos complexes and other non-OxPhos mitochondrial proteins, except for heat shock protein 70, which was increased depending on oxygen level and differentiation status. These two factors were proven to modulate mitochondrial membrane potential and the bioenergetic status of cells. We suggest, moreover, that oxygen plays a role in the differentiation of human SH-SY5Y cells.

Physiological effects of light on the human circadian pacemaker

NASA Technical Reports Server (NTRS)

Shanahan, T. L.; Czeisler, C. A.

2000-01-01

The physiology of the human circadian pacemaker and its influence and on the daily organization of sleep, endocrine and behavioral processes is an emerging interest in science and medicine. Understanding the development, organization and fundamental properties underlying the circadian timing system may provide insight for the application of circadian principles to the practice of clinical medicine, both diagnostically (interpretation of certain clinical tests are dependent on time of day) and therapeutically (certain pharmacological responses vary with the time of day). The light-dark cycle is the most powerful external influence acting upon the human circadian pacemaker. It has been shown that timed exposure to light can both synchronize and reset the phase of the circadian pacemaker in a predictable manner. The emergence of detectable circadian rhythmicity in the neonatal period is under investigation (as described elsewhere in this issue). Therefore, the pattern of light exposure provided in the neonatal intensive care setting has implications. One recent study identified differences in both amount of sleep time and weight gain in infants maintained in a neonatal intensive care environment that controlled the light-dark cycle. Unfortunately, neither circadian phase nor the time of day has been considered in most clinical investigations. Further studies with knowledge of principles characterizing the human circadian timing system, which governs a wide array of physiological processes, are required to integrate these findings with the practice of clinical medicine.

Knowledge environments representing molecular entities for the virtual physiological human.

PubMed

Hofmann-Apitius, Martin; Fluck, Juliane; Furlong, Laura; Fornes, Oriol; Kolárik, Corinna; Hanser, Susanne; Boeker, Martin; Schulz, Stefan; Sanz, Ferran; Klinger, Roman; Mevissen, Theo; Gattermayer, Tobias; Oliva, Baldo; Friedrich, Christoph M

2008-09-13

In essence, the virtual physiological human (VPH) is a multiscale representation of human physiology spanning from the molecular level via cellular processes and multicellular organization of tissues to complex organ function. The different scales of the VPH deal with different entities, relationships and processes, and in consequence the models used to describe and simulate biological functions vary significantly. Here, we describe methods and strategies to generate knowledge environments representing molecular entities that can be used for modelling the molecular scale of the VPH. Our strategy to generate knowledge environments representing molecular entities is based on the combination of information extraction from scientific text and the integration of information from biomolecular databases. We introduce @neuLink, a first prototype of an automatically generated, disease-specific knowledge environment combining biomolecular, chemical, genetic and medical information. Finally, we provide a perspective for the future implementation and use of knowledge environments representing molecular entities for the VPH.

Delineating the Impact of Weightlessness on Human Physiology Using Computational Models

NASA Technical Reports Server (NTRS)

Kassemi, Mohammad

2015-01-01

Microgravity environment has profound effects on several important human physiological systems. The impact of weightlessness is usually indirect as mediated by changes in the biological fluid flow and transport and alterations in the deformation and stress fields of the compliant tissues. In this context, Fluid-Structural and Fluid-Solid Interaction models provide a valuable tool in delineating the physical origins of the physiological changes so that systematic countermeasures can be devised to reduce their adverse effects. In this presentation, impact of gravity on three human physiological systems will be considered. The first case involves prediction of cardiac shape change and altered stress distributions in weightlessness. The second, presents a fluid-structural-interaction (FSI) analysis and assessment of the vestibular system and explores the reasons behind the unexpected microgravity caloric stimulation test results performed aboard the Skylab. The last case investigates renal stone development in microgravity and the possible impact of re-entry into partial gravity on the development and transport of nucleating, growing, and agglomerating renal calculi in the nephron. Finally, the need for model validation and verification and application of the FSI models to assess the effects of Artificial Gravity (AG) are also briefly discussed.

Sickness-induced changes in physiology do not affect fecundity or same-sex behavior.

PubMed

Sylvia, Kristyn E; Báez Ramos, Patricia; Demas, Gregory E

2018-02-01

Previous work in our lab has shown that early-life infection affects female reproductive physiology and function (i.e., smaller ovaries, abnormal estrous cycles) and alters investigation and aggression towards male conspecifics in a reproductive context. Although many studies have investigated the effects of postnatal immune challenge on physiological and behavioral development, fewer studies have examined whether these changes have ultimate effects on reproduction. In the current study, we paired Siberian hamsters (Phodopus sungorus) and simulated a bacterial infection in early life by administering lipopolysaccharide (LPS) to male and female pups on pnd3 and pnd5. In adulthood, hamsters were paired with novel individuals of the same sex, and we scored an array of social behaviors (e.g., investigation, aggression). We then paired animals with individuals of the opposite sex for 5 consecutive nights, providing them with the opportunity to mate. We found that females exhibited impaired reproductive physiology and function in adulthood (i.e., smaller ovaries and abnormal estrous cycles), similar to our previous work. However, both LPS-treated males and females exhibited similar same-sex social behavior when compared with saline-treated controls, they successfully mated, and there were no significant changes in fecundity. These data suggest that the physiological changes in response to neonatal immune challenge may not have long-term effects on reproductive success in a controlled environment. Collectively, the results of this study are particularly important when investigating the relationships between physiology and behavior within an ultimate context. Animals exposed to early-life stress may in fact be capable of compensating for changes in physiology in order to survive and reproduce in some contexts. Copyright © 2017 Elsevier Inc. All rights reserved.

How do humans affect wildlife nematodes?

USGS Publications Warehouse

Weinstein, Sara B.; Lafferty, Kevin D.

2015-01-01

Human actions can affect wildlife and their nematode parasites. Species introductions and human-facilitated range expansions can create new host–parasite interactions. Novel hosts can introduce parasites and have the potential to both amplify and dilute nematode transmission. Furthermore, humans can alter existing nematode dynamics by changing host densities and the abiotic conditions that affect larval parasite survival. Human impacts on wildlife might impair parasites by reducing the abundance of their hosts; however, domestic animal production and complex life cycles can maintain transmission even when wildlife becomes rare. Although wildlife nematodes have many possible responses to human actions, understanding host and parasite natural history, and the mechanisms behind the changing disease dynamics might improve disease control in the few cases where nematode parasitism impacts wildlife.

Communalism predicts prenatal affect, stress, and physiology better than ethnicity and socioeconomic status.

PubMed

Abdou, Cleopatra M; Dunkel Schetter, Christine; Campos, Belinda; Hilmert, Clayton J; Dominguez, Tyan Parker; Hobel, Calvin J; Glynn, Laura M; Sandman, Curt

2010-07-01

The authors examined the relevance of communalism, operationalized as a cultural orientation emphasizing interdependence, to maternal prenatal emotional health and physiology and distinguished its effects from those of ethnicity and childhood and adult socioeconomic status (SES). African American and European American women (N = 297) were recruited early in pregnancy and followed through 32 weeks gestation using interviews and medical chart review. Overall, African American women and women of lower socioeconomic backgrounds had higher levels of negative affect, stress, and blood pressure, but these ethnic and socioeconomic disparities were not observed among women higher in communalism. Hierarchical multivariate regression analyses showed that communalism was a more robust predictor of prenatal emotional health than ethnicity, childhood SES, and adult SES. Communalism also interacted with ethnicity and SES, resulting in lower blood pressure during pregnancy for African American women and women who experienced socioeconomic disadvantage over the life course. The effects of communalism on prenatal affect, stress, and physiology were not explained by depressive symptoms at study entry, perceived availability of social support, self-esteem, optimism, mastery, nor pregnancy-specific factors, including whether the pregnancy was planned, whether the pregnancy was desired after conception, or how frequently the woman felt happy to be pregnant. This suggests that a communal cultural orientation benefits maternal prenatal emotional health and physiology over and above its links to better understood personal and social resources in addition to economic resources. Implications of culture as a determinant of maternal prenatal health and well-being and an important lens for examining ethnic and socioeconomic inequalities in health are discussed.

Affective and physiological responses to the suffering of others: compassion and vagal activity.

PubMed

Stellar, Jennifer E; Cohen, Adam; Oveis, Christopher; Keltner, Dacher

2015-04-01

Compassion is an affective response to another's suffering and a catalyst of prosocial behavior. In the present studies, we explore the peripheral physiological changes associated with the experience of compassion. Guided by long-standing theoretical claims, we propose that compassion is associated with activation in the parasympathetic autonomic nervous system through the vagus nerve. Across 4 studies, participants witnessed others suffer while we recorded physiological measures, including heart rate, respiration, skin conductance, and a measure of vagal activity called respiratory sinus arrhythmia (RSA). Participants exhibited greater RSA during the compassion induction compared with a neutral control (Study 1), another positive emotion (Study 2), and a prosocial emotion lacking appraisals of another person's suffering (Study 3). Greater RSA during the experience of compassion compared with the neutral or control emotion was often accompanied by lower heart rate and respiration but no difference in skin conductance. In Study 4, increases in RSA during compassion positively predicted an established composite of compassion-related words, continuous self-reports of compassion, and nonverbal displays of compassion. Compassion, a core affective component of empathy and prosociality, is associated with heightened parasympathetic activity. (c) 2015 APA, all rights reserved).

Opportunities and constraints of presently used thermal manikins for thermo-physiological simulation of the human body.

PubMed

Psikuta, Agnes; Kuklane, Kalev; Bogdan, Anna; Havenith, George; Annaheim, Simon; Rossi, René M

2016-03-01

Combining the strengths of an advanced mathematical model of human physiology and a thermal manikin is a new paradigm for simulating thermal behaviour of humans. However, the forerunners of such adaptive manikins showed some substantial limitations. This project aimed to determine the opportunities and constraints of the existing thermal manikins when dynamically controlled by a mathematical model of human thermal physiology. Four thermal manikins were selected and evaluated for their heat flux measurement uncertainty including lateral heat flows between manikin body parts and the response of each sector to the frequent change of the set-point temperature typical when using a physiological model for control. In general, all evaluated manikins are suitable for coupling with a physiological model with some recommendations for further improvement of manikin dynamic performance. The proposed methodology is useful to improve the performance of the adaptive manikins and help to provide a reliable and versatile tool for the broad research and development domain of clothing, automotive and building engineering.

Filtration of human EEG recordings from physiological artifacts with empirical mode method

NASA Astrophysics Data System (ADS)

Grubov, Vadim V.; Runnova, Anastasiya E.; Khramova, Marina V.

2017-03-01

In the paper we propose the new method for dealing with noise and physiological artifacts in experimental human EEG recordings. The method is based on analysis of EEG signals with empirical mode decomposition (Hilbert-Huang transform). We consider noises and physiological artifacts on EEG as specific oscillatory patterns that cause problems during EEG analysis and can be detected with additional signals recorded simultaneously with EEG (ECG, EMG, EOG, etc.) We introduce the algorithm of the method with following steps: empirical mode decomposition of EEG signal, choosing of empirical modes with artifacts, removing empirical modes with artifacts, reconstruction of the initial EEG signal. We test the method on filtration of experimental human EEG signals from eye-moving artifacts and show high efficiency of the method.

Local air gap thickness and contact area models for realistic simulation of human thermo-physiological response

NASA Astrophysics Data System (ADS)

Psikuta, Agnes; Mert, Emel; Annaheim, Simon; Rossi, René M.

2018-02-01

To evaluate the quality of new energy-saving and performance-supporting building and urban settings, the thermal sensation and comfort models are often used. The accuracy of these models is related to accurate prediction of the human thermo-physiological response that, in turn, is highly sensitive to the local effect of clothing. This study aimed at the development of an empirical regression model of the air gap thickness and the contact area in clothing to accurately simulate human thermal and perceptual response. The statistical model predicted reliably both parameters for 14 body regions based on the clothing ease allowances. The effect of the standard error in air gap prediction on the thermo-physiological response was lower than the differences between healthy humans. It was demonstrated that currently used assumptions and methods for determination of the air gap thickness can produce a substantial error for all global, mean, and local physiological parameters, and hence, lead to false estimation of the resultant physiological state of the human body, thermal sensation, and comfort. Thus, this model may help researchers to strive for improvement of human thermal comfort, health, productivity, safety, and overall sense of well-being with simultaneous reduction of energy consumption and costs in built environment.

Sex differences in the physiology of eating

PubMed Central

Asarian, Lori

2013-01-01

Hypothalamic-pituitary-gonadal (HPG) axis function fundamentally affects the physiology of eating. We review sex differences in the physiological and pathophysiological controls of amounts eaten in rats, mice, monkeys, and humans. These controls result from interactions among genetic effects, organizational effects of reproductive hormones (i.e., permanent early developmental effects), and activational effects of these hormones (i.e., effects dependent on hormone levels). Male-female sex differences in the physiology of eating involve both organizational and activational effects of androgens and estrogens. An activational effect of estrogens decreases eating 1) during the periovulatory period of the ovarian cycle in rats, mice, monkeys, and women and 2) tonically between puberty and reproductive senescence or ovariectomy in rats and monkeys, sometimes in mice, and possibly in women. Estrogens acting on estrogen receptor-α (ERα) in the caudal medial nucleus of the solitary tract appear to mediate these effects in rats. Androgens, prolactin, and other reproductive hormones also affect eating in rats. Sex differences in eating are mediated by alterations in orosensory capacity and hedonics, gastric mechanoreception, ghrelin, CCK, glucagon-like peptide-1 (GLP-1), glucagon, insulin, amylin, apolipoprotein A-IV, fatty-acid oxidation, and leptin. The control of eating by central neurochemical signaling via serotonin, MSH, neuropeptide Y, Agouti-related peptide (AgRP), melanin-concentrating hormone, and dopamine is modulated by HPG function. Finally, sex differences in the physiology of eating may contribute to human obesity, anorexia nervosa, and binge eating. The variety and physiological importance of what has been learned so far warrant intensifying basic, translational, and clinical research on sex differences in eating. PMID:23904103

40 CFR 230.76 - Actions affecting human use.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Actions affecting human use. 230.76... Minimize Adverse Effects § 230.76 Actions affecting human use. Minimization of adverse effects on human use... aquatic areas; (c) Timing the discharge to avoid the seasons or periods when human recreational activity...

40 CFR 230.76 - Actions affecting human use.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Actions affecting human use. 230.76... Minimize Adverse Effects § 230.76 Actions affecting human use. Minimization of adverse effects on human use... aquatic areas; (c) Timing the discharge to avoid the seasons or periods when human recreational activity...

40 CFR 230.76 - Actions affecting human use.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Actions affecting human use. 230.76... Minimize Adverse Effects § 230.76 Actions affecting human use. Minimization of adverse effects on human use... aquatic areas; (c) Timing the discharge to avoid the seasons or periods when human recreational activity...

40 CFR 230.76 - Actions affecting human use.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Actions affecting human use. 230.76... Minimize Adverse Effects § 230.76 Actions affecting human use. Minimization of adverse effects on human use... aquatic areas; (c) Timing the discharge to avoid the seasons or periods when human recreational activity...

40 CFR 230.76 - Actions affecting human use.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Actions affecting human use. 230.76... Minimize Adverse Effects § 230.76 Actions affecting human use. Minimization of adverse effects on human use... aquatic areas; (c) Timing the discharge to avoid the seasons or periods when human recreational activity...

Adaptive Filtration of Physiological Artifacts in EEG Signals in Humans Using Empirical Mode Decomposition

NASA Astrophysics Data System (ADS)

Grubov, V. V.; Runnova, A. E.; Hramov, A. E.

2018-05-01

A new method for adaptive filtration of experimental EEG signals in humans and for removal of different physiological artifacts has been proposed. The algorithm of the method includes empirical mode decomposition of EEG, determination of the number of empirical modes that are considered, analysis of the empirical modes and search for modes that contains artifacts, removal of these modes, and reconstruction of the EEG signal. The method was tested on experimental human EEG signals and demonstrated high efficiency in the removal of different types of physiological EEG artifacts.

Dealing with noise and physiological artifacts in human EEG recordings: empirical mode methods

NASA Astrophysics Data System (ADS)

Runnova, Anastasiya E.; Grubov, Vadim V.; Khramova, Marina V.; Hramov, Alexander E.

2017-04-01

In the paper we propose the new method for removing noise and physiological artifacts in human EEG recordings based on empirical mode decomposition (Hilbert-Huang transform). As physiological artifacts we consider specific oscillatory patterns that cause problems during EEG analysis and can be detected with additional signals recorded simultaneously with EEG (ECG, EMG, EOG, etc.) We introduce the algorithm of the proposed method with steps including empirical mode decomposition of EEG signal, choosing of empirical modes with artifacts, removing these empirical modes and reconstructing of initial EEG signal. We show the efficiency of the method on the example of filtration of human EEG signal from eye-moving artifacts.

Physiological activity of irradiated green tea polyphenol on the human skin.

PubMed

An, Bong-Jeun; Kwak, Jae-Hoon; Son, Jun-Ho; Park, Jung-Mi; Lee, Jin-Young; Park, Tae Soon; Kim, So-Yeun; Kim, Yeoung-Sun; Jo, Cheorun; Byun, Myung-Woo

2005-01-01

Physiological activity of irradiated green tea polyphenol on the human skin was investigated for further industrial application. The green tea polyphenol was separated and irradiated at 40 kGy by y-ray. For an anti-wrinkle effect, the collagenase inhibition effect was higher in the irradiated sample (65.3%) than that of the non-irradiated control (56.8%) at 200 ppm of the concentration (p < 0.05). Collagen biosynthesis rates using a human fibroblast were 19.4% and 16.3% in the irradiated and the non-irradiated polyphenols, respectively. The tyrosinase inhibition effect, which is related to the skin-whitening effect, showed a 45.2% and 42.9% in the irradiated and the non-irradiated polyphenols, respectively, at a 100 ppm level. A higher than 90% growth inhibition on skin cancer cells (SK-MEL-2 and G361) was demonstrated in both the irradiated and the non-irradiated polyphenols. Thus, the irradiation of green tea polyphenol did not change and even increased its anti-wrinkle, skin-whitening and anticancer effects on the human skin. The results indicated that irradiated green tea polyphenol can be used as a natural ingredient with excellent physiological functions for the human skin through cosmetic or food composition.

Scanpath-based analysis of objects conspicuity in context of human vision physiology.

PubMed

Augustyniak, Piotr

2007-01-01

This paper discusses principal aspects of objects conspicuity investigated with use of an eye tracker and interpreted on the background of human vision physiology. Proper management of objects conspicuity is fundamental in several leading edge applications in the information society like advertisement, web design, man-machine interfacing and ergonomics. Although some common rules of human perception are applied since centuries in the art, the interest of human perception process is motivated today by the need of gather and maintain the recipient attention by putting selected messages in front of the others. Our research uses the visual tasks methodology and series of progressively modified natural images. The modifying details were attributed by their size, color and position while the scanpath-derived gaze points confirmed or not the act of perception. The statistical analysis yielded the probability of detail perception and correlations with the attributes. This probability conforms to the knowledge about the retina anatomy and perception physiology, although we use noninvasive methods only.

Changing undergraduate human anatomy and physiology laboratories: perspectives from a large-enrollment course.

PubMed

Griff, Edwin R

2016-09-01

In the present article, a veteran lecturer of human anatomy and physiology taught several sections of the laboratory component for the first time and shares his observations and analysis from this unique perspective. The article discusses a large-enrollment, content-heavy anatomy and physiology course in relationship to published studies on learning and student self-efficacy. Changes in the laboratory component that could increase student learning are proposed. The author also points out the need for research to assess whether selective curricular changes could increase the depth of understanding and retention of learned material. Copyright © 2016 The American Physiological Society.

Conservation physiology of animal migration

PubMed Central

Lennox, Robert J.; Chapman, Jacqueline M.; Souliere, Christopher M.; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D.; Cooke, Steven J.

2016-01-01

Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains

Conservation physiology of animal migration.

PubMed

Lennox, Robert J; Chapman, Jacqueline M; Souliere, Christopher M; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D; Cooke, Steven J

2016-01-01

Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains

Physiologically Based Pharmacokinetic Model for Terbinafine in Rats and Humans

PubMed Central

Hosseini-Yeganeh, Mahboubeh; McLachlan, Andrew J.

2002-01-01

The aim of this study was to develop a physiologically based pharmacokinetic (PB-PK) model capable of describing and predicting terbinafine concentrations in plasma and tissues in rats and humans. A PB-PK model consisting of 12 tissue and 2 blood compartments was developed using concentration-time data for tissues from rats (n = 33) after intravenous bolus administration of terbinafine (6 mg/kg of body weight). It was assumed that all tissues except skin and testis tissues were well-stirred compartments with perfusion rate limitations. The uptake of terbinafine into skin and testis tissues was described by a PB-PK model which incorporates a membrane permeability rate limitation. The concentration-time data for terbinafine in human plasma and tissues were predicted by use of a scaled-up PB-PK model, which took oral absorption into consideration. The predictions obtained from the global PB-PK model for the concentration-time profile of terbinafine in human plasma and tissues were in close agreement with the observed concentration data for rats. The scaled-up PB-PK model provided an excellent prediction of published terbinafine concentration-time data obtained after the administration of single and multiple oral doses in humans. The estimated volume of distribution at steady state (Vss) obtained from the PB-PK model agreed with the reported value of 11 liters/kg. The apparent volume of distribution of terbinafine in skin and adipose tissues accounted for 41 and 52%, respectively, of the Vss for humans, indicating that uptake into and redistribution from these tissues dominate the pharmacokinetic profile of terbinafine. The PB-PK model developed in this study was capable of accurately predicting the plasma and tissue terbinafine concentrations in both rats and humans and provides insight into the physiological factors that determine terbinafine disposition. PMID:12069977

Using a Combined Approach of Guided Inquiry & Direct Instruction to Explore How Physiology Affects Behavior

ERIC Educational Resources Information Center

Machtinger, Erika T.

2014-01-01

Hands-on activities with live organisms allow students to actively explore scientific investigation. Here, I present activities that combine guided inquiry with direct instruction and relate how nutrition affects the physiology and behavior of the common housefly. These experiments encourage student involvement in the formulation of experimental…

Use of Physiologically Based Pharmacokinetic (PBPK) Models to Quantify the Impact of Human Age and Interindividual Differences in Physiology and Biochemistry Pertinent to Risk (Final Report)

EPA Science Inventory

EPA announced the availability of the final report, Use of Physiologically Based Pharmacokinetic (PBPK) Models to Quantify the Impact of Human Age and Interindividual Differences in Physiology and Biochemistry Pertinent to Risk Final Report for Cooperative Agreement. Th...

Physiological concentrations of anabolic steroids in human hair.

PubMed

Shen, Min; Xiang, Ping; Shen, Baohua; Bu, Jun; Wang, Mengye

2009-01-30

Doping with endogenous anabolic steroids is one of the most serious issues in sports today. The measurement of anabolic steroid levels in human hair is necessary in order to distinguish between pharmaceutical steroids and natural steroids. This is the first investigation into the physiological concentrations of anabolic steroids in human hair in Chinese subjects. A gas chromatography-tandem mass spectrometry (GC/MS/MS) method was developed for the simultaneous identification and quantitation of five endogenous anabolic steroids (testosterone, epitestosterone, androsterone, etiocholanolone and dehydroepiandrosterone) in hair. After basic hydrolysis, hair samples were extracted with diethyl ether, derivatized and then detected using GC/MS/MS in the multiple-reaction monitoring mode (MRM). The one precursor/two product ion transitions for each anabolic steroid were monitored. The limits of detection for the five endogenous anabolic steroids were in the 0.1-0.2 pg/mg range. All analytes showed good linearity and the extraction recoveries were 74.6-104.5%. Within-day and between-day precisions were less than 20%. This method was applied to the analysis of testosterone, epitestosterone, androsterone, etiocholanolone, and dehydroepiandrosterone in human hair. Full-length hair samples were taken at the skin surface from the vertex of 39 males, 30 females and 11 children from China. None of the subjects were professional athletes. Testosterone and dehydroepiandrosterone were detected in all the hair segments. The physiological concentrations of testosterone were in the range 0.8-24.2 pg/mg, 0.1-16.8 pg/mg and 0.2-11.5 pg/mg in males, females and children, respectively, however, the mean values of dehydroepiandrosterone were much higher than the concentrations of testosterone. These data are suitable reference values and are the basis for the interpretation of results from investigations into the abuse of endogenous anabolic steroids.

Childhood adversity predicts reduced physiological flexibility during the processing of negative affect among adolescents with major depression histories.

PubMed

Daches, Shimrit; Kovacs, Maria; George, Charles J; Yaroslavsky, Ilya; Kiss, Eniko; Vetró, Ágnes; Dochnal, Roberta; Benák, István; Baji, Ildikó; Halas, Kitti; Makai, Attila; Kapornai, Krisztina; Rottenberg, Jonathan

2017-11-01

Adversity during early development has been shown to have enduring negative physiological consequences. In turn, atypical physiological functioning has been associated with maladaptive processing of negative affect, including its regulation. The present study therefore explored whether exposure to adverse life events in childhood predicted maladaptive (less flexible) parasympathetic nervous system functioning during the processing of negative affect among adolescents with depression histories. An initially clinic-referred, pediatric sample (N=189) was assessed at two time points. At Time 1, when subjects were 10.17years old (SD=1.42), on average, and were depressed, parents reported on adverse life events the offspring experienced up to that point. At Time 2, when subjects were 17.18years old (SD=1.28), and were remitted from depression, parents again reported on adverse life events in their offspring's lives for the interim period. At time 2, subjects' parasympathetic nervous system functioning (quantified as respiratory sinus arrhythmia) also was assessed at rest, during sad mood induction, and during instructed mood repair. Extent of adverse life events experienced by T1 (but not events occurring between T1 and T2) predicted less flexible RSA functioning 7years later during the processing of negative affect. Adolescents with more extensive early life adversities exhibited less vagal withdrawal following negative mood induction and tended to show less physiological recovery following mood repair. Early adversities appear to be associated with less flexible physiological regulatory control during negative affect experience, when measured later in development. Stress-related autonomic dysfunction in vulnerable youths may contribute to the unfavorable clinical prognosis associated with juvenile-onset depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of torque-limits for human and cat lumbar spine specimens during displacement-controlled physiological motions.

PubMed

Ianuzzi, Allyson; Pickar, Joel G; Khalsa, Partap S

2009-01-01

Quadruped animal models have been validated and used as biomechanical models for the lumbar spine. The biomechanics of the cat lumbar spine has not been well characterized, even though it is a common model used in neuromechanical studies. Compare the physiological ranges of motion and determine torque-limits for cat and human lumbar spine specimens during physiological motions. Biomechanics study. Cat and human lumbar spine specimens. Intervertebral angle (IVA), joint moment, yield point, torque-limit, and correlation coefficients. Cat (L2-sacrum) and human (T12-sacrum) lumbar spine specimens were mechanically tested to failure during displacement-controlled extension (E), lateral bending (LB), and axial rotation (AR). Single trials consisted of 10 cycles (10mm/s or 5 degrees /s) to a target displacement where the magnitude of the target displacement was increased for subsequent trials until failure occurred. Whole-lumbar stiffness, torque at yield point, and joint stiffness were determined. Scaling relationships were established using equations analogous to those that describe the load response of elliptically shaped beams. IVA magnitudes for cat and human lumbar spines were similar during physiological motions. Human whole-lumbar and joint stiffness magnitudes were significantly greater than those for cat spine specimens (p<.05). Torque-limits were also greater for humans compared with cats. Scaling relationships with high correlation (R(2) greater than 0.77) were established during later LB and AR. The current study defined "physiological ranges of movement" for human and cat lumbar spine specimens during displacement-controlled testing, and should be observed in future biomechanical studies conducted under displacement control.

Impact of physiological, physicochemical and biopharmaceutical factors in absorption and metabolism mechanisms on the drug oral bioavailability of rats and humans.

PubMed

Hurst, Susan; Loi, Cho-Ming; Brodfuehrer, Joanne; El-Kattan, Ayman

2007-08-01

The onset, intensity and duration of therapeutic response to a compound depend on the intrinsic pharmacological activity of the drug and pharmacokinetic factors related to its absorption, distribution, metabolism and elimination that are inherent to the biological system. The process of drug transfer from the site of administration to the systemic circulation and the interspecies factors that impact this process are the scope of this review. In general, the factors that influence oral drug bioavailability via absorption and metabolism can be divided into physicochemical/biopharmaceutical and physiological factors. Physicochemical and biopharmaceutical factors that influence permeability and solubility tend to be species independent. Although there are significant differences in the anatomy and physiology of the gastrointestinal tract, these are not associated with significant differences in the rate and extent of drug absorption between rats and humans. However, species differences in drug metabolism in rats and humans did result in significant species differences in bioavailability. Overall, this review provides a better understanding of the interplay between drug physicochemical/biopharmaceutical factors and species differences/similarities in the absorption and metabolism mechanisms that affect oral bioavailability in rats and humans. This will enable a more rational approach to perform projection of oral bioavailability in human using available rat in vivo data.

A novel non-contact radar sensor for affective and interactive analysis.

PubMed

Lin, Hong-Dun; Lee, Yen-Shien; Shih, Hsiang-Lan; Chuang, Bor-Nian

2013-01-01

Currently, many physiological signal sensing techniques have been applied for affective analysis in Human-Computer Interaction applications. Most known maturely developed sensing methods (EEG/ECG/EMG/Temperature/BP etc. al.) replied on contact way to obtain desired physiological information for further data analysis. However, those methods might cause some inconvenient and uncomfortable problems, and not easy to be used for affective analysis in interactive performing. To improve this issue, a novel technology based on low power radar technology (Nanosecond Pulse Near-field Sensing, NPNS) with 300 MHz radio-frequency was proposed to detect humans' pulse signal by the non-contact way for heartbeat signal extraction. In this paper, a modified nonlinear HRV calculated algorithm was also developed and applied on analyzing affective status using extracted Peak-to-Peak Interval (PPI) information from detected pulse signal. The proposed new affective analysis method is designed to continuously collect the humans' physiological signal, and validated in a preliminary experiment with sound, light and motion interactive performance. As a result, the mean bias between PPI (from NPNS) and RRI (from ECG) shows less than 1ms, and the correlation is over than 0.88, respectively.

Dynamic physiological modeling for functional diffuse optical tomography

PubMed Central

Diamond, Solomon Gilbert; Huppert, Theodore J.; Kolehmainen, Ville; Franceschini, Maria Angela; Kaipio, Jari P.; Arridge, Simon R.; Boas, David A.

2009-01-01

Diffuse optical tomography (DOT) is a noninvasive imaging technology that is sensitive to local concentration changes in oxy- and deoxyhemoglobin. When applied to functional neuroimaging, DOT measures hemodynamics in the scalp and brain that reflect competing metabolic demands and cardiovascular dynamics. The diffuse nature of near-infrared photon migration in tissue and the multitude of physiological systems that affect hemodynamics motivate the use of anatomical and physiological models to improve estimates of the functional hemodynamic response. In this paper, we present a linear state-space model for DOT analysis that models the physiological fluctuations present in the data with either static or dynamic estimation. We demonstrate the approach by using auxiliary measurements of blood pressure variability and heart rate variability as inputs to model the background physiology in DOT data. We evaluate the improvements accorded by modeling this physiology on ten human subjects with simulated functional hemodynamic responses added to the baseline physiology. Adding physiological modeling with a static estimator significantly improved estimates of the simulated functional response, and further significant improvements were achieved with a dynamic Kalman filter estimator (paired t tests, n = 10, P < 0.05). These results suggest that physiological modeling can improve DOT analysis. The further improvement with the Kalman filter encourages continued research into dynamic linear modeling of the physiology present in DOT. Cardiovascular dynamics also affect the blood-oxygen-dependent (BOLD) signal in functional magnetic resonance imaging (fMRI). This state-space approach to DOT analysis could be extended to BOLD fMRI analysis, multimodal studies and real-time analysis. PMID:16242967

Human physiological responses to cold exposure: Acute responses and acclimatization to prolonged exposure.

PubMed

Castellani, John W; Young, Andrew J

2016-04-01

Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration. Published by Elsevier B.V.

[Human orgasm from the physiological perspective--part I].

PubMed

Gałecki, Piotr; Depko, Andrzej; Jedrzejewska, Sylwia; Talarowska, Monika

2012-07-01

Physiological phenomenon of sexuality occurring in both sexes that brings physical and mental satisfaction, and often affects the quality of life is an orgasm. The ability to experience regular orgasms affects relationship with partner. The definition of orgasm is not an easy task. The way of experiencing it is subjective, and the possibility of observing significantly reduced. Contemporary works on the phenomenon of orgasm are concentrated on several aspects: biological perspective (neurophysiological and biochemical determinants of orgasm), psychological perspective and on the differences in its course in both sexes. In sexology are two models of sexual response: a linear model of sexual response (by W. Masters and V. Johnson, and H. S. Kaplan) and the circular model of sexual response (created by R. Basson). The ability to experiencing an orgasm is inherent in men. In women, that phenomenon is acquired, is the consequence of further experience.

Is Lutein a Physiologically Important Ligand for Transthyretin in Humans?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Liwei

Lutein and zeaxanthin are the only carotenoids accumulated in the macula of the human retina and are known as the macular pigments (MP). These pigments account for the yellow color of the macula and appear to play an important role in protecting against age-related macular degeneration (AMD). The uptake of lutein and zeaxanthin in human eyes is remarkably specific. It is likely that specific transport or binding proteins are involved. The objective is to determine whether transthyretin (TTR) is a transport protein in human plasma and could thus deliver lutein from the blood to the retina. In this study, theymore » used a biosynthetic 13C-lutein tracer and gas chromatography-combustion interfaced-isotope ratio mass spectrometry (GCC-IRMS) to gain the requisite sensitivity to detect the minute amounts of lutein expected as a physiological ligand for human transthyretin. The biosynthetic 13C-labeled lutein tracer was purified from algae. Healthy women (n = 4) each ingested 1 mg of 13C-labeled lutein daily for 3 days and a blood sample was collected 24 hours after the final dose. Plasma TTR was isolated by retinol-binding protein (RBP)-sepharose affinity chromatography and extracted with chloroform. The 13C/ 12C ratio in the TTR extract was measured by GCC-IRMS. There was no 13C-lutein enrichment in the pure TTR extract. This result indicated that lutein is not associated with TTR in human plasma after ingestion in physiological amounts. Some hydrophobic compounds with yellow color may bind to human TTR in the plasma. However, this association needs to be further proved by showing specificity. The study provides a new approach for carotenoid-binding protein studies using a stable isotope tracer method combined with the high precision of GCC-IRMS. The mechanism of selective transport, uptake, and accumulation of lutein in human macula remain to be determined.« less

Metabolomic profiles indicate distinct physiological pathways affected by two loci with major divergent effect on Bos taurus growth and lipid deposition.

PubMed

Weikard, Rosemarie; Altmaier, Elisabeth; Suhre, Karsten; Weinberger, Klaus M; Hammon, Harald M; Albrecht, Elke; Setoguchi, Kouji; Takasuga, Akiko; Kühn, Christa

2010-10-01

Identifying trait-associated genetic variation offers new prospects to reveal novel physiological pathways modulating complex traits. Taking advantage of a unique animal model, we identified the I442M mutation in the non-SMC condensin I complex, subunit G (NCAPG) gene and the Q204X mutation in the growth differentiation factor 8 (GDF8) gene as substantial modulators of pre- and/or postnatal growth in cattle. In a combined metabolomic and genotype association approach, which is the first respective study in livestock, we surveyed the specific physiological background of the effects of both loci on body-mass gain and lipid deposition. Our data provided confirming evidence from two historically and geographically distant cattle populations that the onset of puberty is the key interval of divergent growth. The locus-specific metabolic patterns obtained from monitoring 201 plasma metabolites at puberty mirror the particular NCAPG I442M and GDF8 Q204X effects and represent biosignatures of divergent physiological pathways potentially modulating effects on proportional and disproportional growth, respectively. While the NCAPG I442M mutation affected the arginine metabolism, the 204X allele in the GDF8 gene predominantly raised the carnitine level and had concordant effects on glycerophosphatidylcholines and sphingomyelins. Our study provides a conclusive link between the well-described growth-regulating functions of arginine metabolism and the previously unknown specific physiological role of the NCAPG protein in mammalian metabolism. Owing to the confirmed effect of the NCAPG/LCORL locus on human height in genome-wide association studies, the results obtained for bovine NCAPG might add valuable, comparative information on the physiological background of genetically determined divergent mammalian growth.

Effects of weightlessness on human fluid and electrolyte physiology

NASA Technical Reports Server (NTRS)

Leach, Carolyn S.; Johnson, Philip C., Jr.

1991-01-01

Skylab and Spacelab data on changes occurring in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. The combined results for all three Spacelab studies show that hyponatremia developed within 20 h after the onset of weightlessness and continued throughout the flights, and hypokalemia developed by 40 h. Antidiuretic hormone was increased in plasma throughout the flights. Aldosterone decreased by 40 h, but after 7 days it had reached preflight levels.

Flexible and wearable electronic silk fabrics for human physiological monitoring

NASA Astrophysics Data System (ADS)

Mao, Cuiping; Zhang, Huihui; Lu, Zhisong

2017-09-01

The development of textile-based devices for human physiological monitoring has attracted tremendous interest in recent years. However, flexible physiological sensing elements based on silk fabrics have not been realized. In this paper, ZnO nanorod arrays are grown in situ on reduced graphene oxide-coated silk fabrics via a facile electro-deposition method for the fabrication of silk-fabric-based mechanical sensing devices. The data show that well-aligned ZnO nanorods with hexagonal wurtzite crystalline structures are synthesized on the conductive silk fabric surface. After magnetron sputtering of gold electrodes, silk-fabric-based devices are produced and applied to detect periodic bending and twisting. Based on the electric signals, the deformation and release processes can be easily differentiated. Human arterial pulse and respiration can also be real-time monitored to calculate the pulse rate and respiration frequency, respectively. Throat vibrations during coughing and singing are detected to demonstrate the voice recognition capability. This work may not only help develop silk-fabric-based mechanical sensing elements for potential applications in clinical diagnosis, daily healthcare monitoring and voice recognition, but also provide a versatile method for fabricating textile-based flexible electronic devices.

Virtual physiological human: training challenges.

PubMed

Lawford, Patricia V; Narracott, Andrew V; McCormack, Keith; Bisbal, Jesus; Martin, Carlos; Bijnens, Bart; Brook, Bindi; Zachariou, Margarita; Freixa, Jordi Villà I; Kohl, Peter; Fletcher, Katherine; Diaz-Zuccarini, Vanessa

2010-06-28

The virtual physiological human (VPH) initiative encompasses a wide range of activities, including structural and functional imaging, data mining, knowledge discovery tool and database development, biomedical modelling, simulation and visualization. The VPH community is developing from a multitude of relatively focused, but disparate, research endeavours into an integrated effort to bring together, develop and translate emerging technologies for application, from academia to industry and medicine. This process initially builds on the evolution of multi-disciplinary interactions and abilities, but addressing the challenges associated with the implementation of the VPH will require, in the very near future, a translation of quantitative changes into a new quality of highly trained multi-disciplinary personnel. Current strategies for undergraduate and on-the-job training may soon prove insufficient for this. The European Commission seventh framework VPH network of excellence is exploring this emerging need, and is developing a framework of novel training initiatives to address the predicted shortfall in suitably skilled VPH-aware professionals. This paper reports first steps in the implementation of a coherent VPH training portfolio.

Food Affects Human Behavior.

ERIC Educational Resources Information Center

Kolata, Gina

1982-01-01

A conference on whether food and nutrients affect human behavior was held on November 9, 1982 at the Massachusetts Institute of Technology. Various research studies on this topic are reviewed, including the effects of food on brain biochemistry (particularly sleep) and effects of tryptophane as a pain reducer. (JN)

Physiology and culture of the human blastocyst.

PubMed

Gardner, David K; Lane, Michelle; Schoolcraft, William B

2002-01-01

The human embryo undergoes many changes in physiology during the first 4 days of life as it develops and differentiates from a fertilized oocyte to the blastocyst stage. Concomitantly, the embryo is exposed to gradients of nutrients within the female reproductive tract and exhibits changes in its own nutrient requirements and utilization. Determining the nature of such nutrient gradients in the female tract and the changing requirements of the embryo has facilitated the formulation of stage-specific culture media designed to support embryo development throughout the preimplantation period. Resultant implantation rates attained with the culture and transfer of human blastocysts are higher than those associated with the transfer of cleavage stage embryos to the uterus. Such increases in implantation rates have facilitated the establishment of high pregnancy rates while reducing the number of embryos transferred. With the introduction of new scoring systems for the blastocyst and the non-invasive assessment of metabolic activity of individual embryos, it should be possible to move to single blastocyst transfer for the majority of patients.

Animal models and their importance to human physiological responses in microgravity

NASA Technical Reports Server (NTRS)

Tipton, C. M.

1996-01-01

Two prominent theories to explain the physiological effects of microgravity relate to the cascade of changes associated with the cephalic shifts of fluids and the absence of tissue deformation forces. One-g experiments for humans used bed rest and the head-down tilt (HDT) method, while animal experiments have been conducted using the tail-suspended, head-down, and hindlimbs non-weightbearing model. Because of the success of the HDT approach with rats to simulate the gravitational effects on the musculoskeletal system exhibited by humans, the same model has been used to study the effects of gravity on the cardiopulmonary systems of humans and other vertebrates. Results to date indicate the model is effective in producing comparable changes associated with blood volume, erythropoiesis, cardiac mass, baroreceptor responsiveness, carbohydrate metabolism, post-flight VO2max, and post-flight cardiac output during exercise. Inherent with these results is the potential of the model to be useful in investigating responsible mechanisms. The suspension model has promise in understanding the capillary blood PO2 changes in space as well as the arterial PO2 changes in subjects participating in a HDT experiment. However, whether the model can provide insights on the up-or-down regulation of adrenoreceptors remains to be determined, and many investigators believe the HDT approach should not be followed to study gravitational influences on pulmonary function in either humans or animals. It was concluded that the tail-suspended animal model had sufficient merit to study in-flight and post-flight human physiological responses and mechanisms.

Correlated physiological and perceptual effects of noise in a tactile stimulus.

PubMed

Lak, Armin; Arabzadeh, Ehsan; Harris, Justin A; Diamond, Mathew E

2010-04-27

We investigated connections between the physiology of rat barrel cortex neurons and the sensation of vibration in humans. One set of experiments measured neuronal responses in anesthetized rats to trains of whisker deflections, each train characterized either by constant amplitude across all deflections or by variable amplitude ("amplitude noise"). Firing rate and firing synchrony were, on average, boosted by the presence of noise. However, neurons were not uniform in their responses to noise. Barrel cortex neurons have been categorized as regular-spiking units (putative excitatory neurons) and fast-spiking units (putative inhibitory neurons). Among regular-spiking units, amplitude noise caused a higher firing rate and increased cross-neuron synchrony. Among fast-spiking units, noise had the opposite effect: It led to a lower firing rate and decreased cross-neuron synchrony. This finding suggests that amplitude noise affects the interaction between inhibitory and excitatory neurons. From these physiological effects, we expected that noise would lead to an increase in the perceived intensity of a vibration. We tested this notion using psychophysical measurements in humans. As predicted, subjects overestimated the intensity of noisy vibrations. Thus the physiological mechanisms present in barrel cortex also appear to be at work in the human tactile system, where they affect vibration perception.

RADIOISOTOPES IN MEDICINE AND HUMAN PHYSIOLOGY. A Selected List of References

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCormick, J.A. comp.

1958-08-01

This bibliography contains 2862 references on uses of radioisotopes in diagnostic medicine, therapeutic medicine, clinical research, human physiology, general medical research, and immunology. The references were taken from the 1948 to 1956 open literature. A list of the journals from which the references were selected and an author index are included. (auth)'

Molecular clocks and the human condition: approaching their characterization in human physiology and disease.

PubMed

Fitzgerald, G A; Yang, G; Paschos, G K; Liang, X; Skarke, C

2015-09-01

Molecular clockworks knit together diverse biological networks and compelling evidence from model systems infers their importance in metabolism, immunological and cardiovascular function. Despite this and the diurnal variation in many aspects of human physiology and the phenotypic expression of disease, our understanding of the role and importance of clock function and dysfunction in humans is modest. There are tantalizing hints of connection across the translational divide and some correlative evidence of gene variation and human disease but most of what we know derives from forced desynchrony protocols in controlled environments. We now have the ability to monitor quantitatively ex vivo or in vivo the genome, metabolome, proteome and microbiome of humans in the wild. Combining this capability, with the power of mobile telephony and the evolution of remote sensing, affords a new opportunity for deep phenotyping, including the characterization of diurnal behaviour and the assessment of the impact of the clock on approved drug function. © 2015 John Wiley & Sons Ltd.

Emotions over time: synchronicity and development of subjective, physiological, and facial affective reactions to music.

PubMed

Grewe, Oliver; Nagel, Frederik; Kopiez, Reinhard; Altenmüller, Eckart

2007-11-01

Most people are able to identify basic emotions expressed in music and experience affective reactions to music. But does music generally induce emotion? Does it elicit subjective feelings, physiological arousal, and motor reactions reliably in different individuals? In this interdisciplinary study, measurement of skin conductance, facial muscle activity, and self-monitoring were synchronized with musical stimuli. A group of 38 participants listened to classical, rock, and pop music and reported their feelings in a two-dimensional emotion space during listening. The first entrance of a solo voice or choir and the beginning of new sections were found to elicit interindividual changes in subjective feelings and physiological arousal. Quincy Jones' "Bossa Nova" motivated movement and laughing in more than half of the participants. Bodily reactions such as "goose bumps" and "shivers" could be stimulated by the "Tuba Mirum" from Mozart's Requiem in 7 of 38 participants. In addition, the authors repeated the experiment seven times with one participant to examine intraindividual stability of effects. This exploratory combination of approaches throws a new light on the astonishing complexity of affective music listening.

Physiologically based pharmacokinetic modeling of tea catechin mixture in rats and humans.

PubMed

Law, Francis C P; Yao, Meicun; Bi, Hui-Chang; Lam, Stephen

2017-06-01

Although green tea ( Camellia sinensis) (GT) contains a large number of polyphenolic compounds with anti-oxidative and anti-proliferative activities, little is known of the pharmacokinetics and tissue dose of tea catechins (TCs) as a chemical mixture in humans. The objectives of this study were to develop and validate a physiologically based pharmacokinetic (PBPK) model of tea catechin mixture (TCM) in rats and humans, and to predict an integrated or total concentration of TCM in the plasma of humans after consuming GT or Polyphenon E (PE). To this end, a PBPK model of epigallocatechin gallate (EGCg) consisting of 13 first-order, blood flow-limited tissue compartments was first developed in rats. The rat model was scaled up to humans by replacing its physiological parameters, pharmacokinetic parameters and tissue/blood partition coefficients (PCs) with human-specific values. Both rat and human EGCg models were then extrapolated to other TCs by substituting its physicochemical parameters, pharmacokinetic parameters, and PCs with catechin-specific values. Finally, a PBPK model of TCM was constructed by linking three rat (or human) tea catechin models together without including a description for pharmacokinetic interaction between the TCs. The mixture PBPK model accurately predicted the pharmacokinetic behaviors of three individual TCs in the plasma of rats and humans after GT or PE consumption. Model-predicted total TCM concentration in the plasma was linearly related to the dose consumed by humans. The mixture PBPK model is able to translate an external dose of TCM into internal target tissue doses for future safety assessment and dose-response analysis studies in humans. The modeling framework as described in this paper is also applicable to the bioactive chemical in other plant-based health products.

Widespread seasonal gene expression reveals annual differences in human immunity and physiology

PubMed Central

Dopico, Xaquin Castro; Evangelou, Marina; Ferreira, Ricardo C.; Guo, Hui; Pekalski, Marcin L.; Smyth, Deborah J.; Cooper, Nicholas; Burren, Oliver S.; Fulford, Anthony J.; Hennig, Branwen J.; Prentice, Andrew M.; Ziegler, Anette-G.; Bonifacio, Ezio; Wallace, Chris; Todd, John A.

2015-01-01

Seasonal variations are rarely considered a contributing component to human tissue function or health, although many diseases and physiological process display annual periodicities. Here we find more than 4,000 protein-coding mRNAs in white blood cells and adipose tissue to have seasonal expression profiles, with inverted patterns observed between Europe and Oceania. We also find the cellular composition of blood to vary by season, and these changes, which differ between the United Kingdom and The Gambia, could explain the gene expression periodicity. With regards to tissue function, the immune system has a profound pro-inflammatory transcriptomic profile during European winter, with increased levels of soluble IL-6 receptor and C-reactive protein, risk biomarkers for cardiovascular, psychiatric and autoimmune diseases that have peak incidences in winter. Circannual rhythms thus require further exploration as contributors to various aspects of human physiology and disease. PMID:25965853

The human cerebellum: a review of physiologic neuroanatomy.

PubMed

Roostaei, Tina; Nazeri, Arash; Sahraian, Mohammad Ali; Minagar, Alireza

2014-11-01

The cerebellum resides in the posterior cranial fossa dorsal to the brainstem and has diverse connections to the cerebrum, brain stem, and spinal cord. It is anatomically and physiologically divided into distinct functional compartments and is composed of highly regular arrays of neuronal units, each sharing the same basic cerebellar microcircuitry. Its circuitry is critically involved in motor control and motor learning, and its role in nonmotor cognitive and affective functions is becoming increasingly recognized. This article describes the cerebellar gross and histologic neuroanatomy in relation to its function, and the relevance of cerebellar circuitry and firing patterns to motor learning. Copyright © 2014 Elsevier Inc. All rights reserved.

Columbus payload requirements in human physiology

NASA Astrophysics Data System (ADS)

Stegemann, Juergen

1993-03-01

Most of the biological feedback loops in the human body are interrelated. This means that several different parameters have to be recorded simultaneously to understand the interrelationship of different subsystems within the body when fast and slow adaptation processes are to be studied. This determines the requirements for the payload in the Columbus module. In 1988 ESA asked some European scientists in different fields of physiology to provide a 'science study' for the Columbus payload requirements. Their report was the basis of a phase A study completed in December 1991, concerning the 'ANTHROLAB', a laboratory that covers all presently known research challenges in this area. Anthrolab is more or less an improvement of the Anthrorack to be flown on the German Spacelab mission D-2 and on the Columbus precursor flight E-1. Beside the present Anthrorack design, Anthrolab will also provide subelements for vestibular, neurophysiological, and biomechanical research.

Radiative and Physiological Effects of Increased CO2. How does this interaction affect Climate in the Mediterranean Region?

NASA Technical Reports Server (NTRS)

Bounoua, Lahouari

2007-01-01

the radiative and physiological effects of doubled atmospheric carbon dioxide concentration (CO2) on climate are described using climate simulations. When CO2 was increased for vegetation only assuming no radiative effect, the response was a decrease in stomatal conductance followed by a temperature increase. This temperature increase was stronger when the vegetation physiological down-regulation was allowed in the model. The radiative forcing alone did not affect the global mean photosynthesis, however, some stimulation was observed in cold places. The interactions between the physiological and the radiative effects of doubled CO2 are not linearly additive and when acting together they tend to reduce the warming in the Mediterranean region.

Pulpal status of human primary teeth with physiological root resorption.

PubMed

Monteiro, Joana; Day, Peter; Duggal, Monty; Morgan, Claire; Rodd, Helen

2009-01-01

The overall aim of this study was to determine whether any changes occur in the pulpal structure of human primary teeth in association with physiological root resorption. The experimental material comprised 64 sound primary molars, obtained from children requiring routine dental extractions under general anaesthesia. Pulp sections were processed for indirect immunofluorescence using combinations of: (i) protein gene product 9.5 (a general neuronal marker); (ii) leucocyte common antigen CD45 (a general immune cell marker); and (iii) Ulex europaeus I lectin (a marker of vascular endothelium). Image analysis was then used to determine the percentage area of staining for each label within both the pulp horn and mid-coronal region. Following measurement of the greatest degree of root resorption in each sample, teeth were subdivided into three groups: those with physiological resorption involving less than one-third, one-third to two-thirds, and more than two-thirds of their root length. Wide variation was evident between different tooth samples with some resorbed teeth showing marked changes in pulpal histology. Decreased innervation density, increased immune cell accumulation, and increased vascularity were evident in some teeth with advanced root resorption. Analysis of pooled data, however, did not reveal any significant differences in mean percentage area of staining for any of these variables according to the three root resorption subgroups (P > 0.05, analysis of variance on transformed data). This investigation has revealed some changes in pulpal status of human primary teeth with physiological root resorption. These were not, however, as profound as one may have anticipated. It is therefore speculated that teeth could retain the potential for sensation, healing, and repair until advanced stages of root resorption.

Young Children’s Affective Responses to Another’s Distress: Dynamic and Physiological Features

PubMed Central

Fink, Elian; Heathers, James A. J.; de Rosnay, Marc

2015-01-01

Two descriptive studies set out a new approach for exploring the dynamic features of children’s affective responses (sadness and interest-worry) to another’s distress. In two samples (N study1 = 75; N study2 = 114), Kindergarten children were shown a video-vignette depicting another child in distress and the temporal pattern of spontaneous expressions were examined across the unfolding vignette. Results showed, in both study 1 and 2, that sadness and interest-worry had distinct patterns of elicitation across the events of the vignette narrative and there was little co-occurrence of these affects within a given child. Temporal heart rate changes (study 2) were closely aligned to the events of the vignette and, furthermore, affective responses corresponded to distinctive physiological response profiles. The implications of distinct temporal patterns of elicitation for the meaning of sadness and interest-worry are discussed within the framework of emotion regulation and empathy. PMID:25874952

Building an experimental model of the human body with non-physiological parameters.

PubMed

Labuz, Joseph M; Moraes, Christopher; Mertz, David R; Leung, Brendan M; Takayama, Shuichi

2017-03-01

New advances in engineering and biomedical technology have enabled recent efforts to capture essential aspects of human physiology in microscale, in-vitro systems. The application of these advances to experimentally model complex processes in an integrated platform - commonly called a 'human-on-a-chip (HOC)' - requires that relevant compartments and parameters be sized correctly relative to each other and to the system as a whole. Empirical observation, theoretical treatments of resource distribution systems and natural experiments can all be used to inform rational design of such a system, but technical and fundamental challenges (e.g. small system blood volumes and context-dependent cell metabolism, respectively) pose substantial, unaddressed obstacles. Here, we put forth two fundamental principles for HOC design: inducing in-vivo -like cellular metabolic rates is necessary and may be accomplished in-vitro by limiting O 2 availability and that the effects of increased blood volumes on drug concentration can be mitigated through pharmacokinetics-based treatments of solute distribution. Combining these principles with natural observation and engineering workarounds, we derive a complete set of design criteria for a practically realizable, physiologically faithful, five-organ millionth-scale (× 10 -6 ) microfluidic model of the human body.

Measuring positive and negative affect and physiological hyperarousal among Serbian youth.

PubMed

Stevanovic, Dejan; Laurent, Jeff; Lakic, Aneta

2013-01-01

This study extended previous cross-cultural work regarding the tripartite model of anxiety and depression by developing Serbian translations of the Positive and Negative Affect Scale for Children (PANAS-C), the Physiological Hyperarousal Scale for Children (PH-C), and the Affect and Arousal Scale (AFARS). Characteristics of the scales were examined using 449 students (M age = 12.61 years). Applying item retention criteria established in other studies, PH-C, PANAS-C, and AFARS translations with psychometric properties similar to English-language versions were identified. Preliminary validation of the scales was conducted using a subset of 194 students (M age = 12.37 years) who also completed measures of anxiety and depression. Estimates of reliability, patterns of correlations among scales, and age and gender differences were consistent with previous studies with English-speaking samples. Findings regarding scale validity were mixed, although consistent with existing literature. Serbian translations of the PH-C, PANAS-C, and AFARS mirror the original English-language scales in terms of both strengths and weaknesses.

Is it the real deal? Perception of virtual characters versus humans: an affective cognitive neuroscience perspective

PubMed Central

de Borst, Aline W.; de Gelder, Beatrice

2015-01-01

Recent developments in neuroimaging research support the increased use of naturalistic stimulus material such as film, avatars, or androids. These stimuli allow for a better understanding of how the brain processes information in complex situations while maintaining experimental control. While avatars and androids are well suited to study human cognition, they should not be equated to human stimuli. For example, the uncanny valley hypothesis theorizes that artificial agents with high human-likeness may evoke feelings of eeriness in the human observer. Here we review if, when, and how the perception of human-like avatars and androids differs from the perception of humans and consider how this influences their utilization as stimulus material in social and affective neuroimaging studies. First, we discuss how the appearance of virtual characters affects perception. When stimuli are morphed across categories from non-human to human, the most ambiguous stimuli, rather than the most human-like stimuli, show prolonged classification times and increased eeriness. Human-like to human stimuli show a positive linear relationship with familiarity. Secondly, we show that expressions of emotions in human-like avatars can be perceived similarly to human emotions, with corresponding behavioral, physiological and neuronal activations, with exception of physical dissimilarities. Subsequently, we consider if and when one perceives differences in action representation by artificial agents versus humans. Motor resonance and predictive coding models may account for empirical findings, such as an interference effect on action for observed human-like, natural moving characters. However, the expansion of these models to explain more complex behavior, such as empathy, still needs to be investigated in more detail. Finally, we broaden our outlook to social interaction, where virtual reality stimuli can be utilized to imitate complex social situations. PMID:26029133

Study of Physiological Responses to Acute Carbon Monoxide Exposure with a Human Patient Simulator

ERIC Educational Resources Information Center

Cesari, Whitney A.; Caruso, Dominique M.; Zyka, Enela L.; Schroff, Stuart T.; Evans, Charles H., Jr.; Hyatt, Jon-Philippe K.

2006-01-01

Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design,…

Estimating psycho-physiological state of a human by speech analysis

NASA Astrophysics Data System (ADS)

Ronzhin, A. L.

2005-05-01

Adverse effects of intoxication, fatigue and boredom could degrade performance of highly trained operators of complex technical systems with potentially catastrophic consequences. Existing physiological fitness for duty tests are time consuming, costly, invasive, and highly unpopular. Known non-physiological tests constitute a secondary task and interfere with the busy workload of the tested operator. Various attempts to assess the current status of the operator by processing of "normal operational data" often lead to excessive amount of computations, poorly justified metrics, and ambiguity of results. At the same time, speech analysis presents a natural, non-invasive approach based upon well-established efficient data processing. In addition, it supports both behavioral and physiological biometric. This paper presents an approach facilitating robust speech analysis/understanding process in spite of natural speech variability and background noise. Automatic speech recognition is suggested as a technique for the detection of changes in the psycho-physiological state of a human that typically manifest themselves by changes of characteristics of voice tract and semantic-syntactic connectivity of conversation. Preliminary tests have confirmed that the statistically significant correlation between the error rate of automatic speech recognition and the extent of alcohol intoxication does exist. In addition, the obtained data allowed exploring some interesting correlations and establishing some quantitative models. It is proposed to utilize this approach as a part of fitness for duty test and compare its efficiency with analyses of iris, face geometry, thermography and other popular non-invasive biometric techniques.

[The physiological classification of human thermal states under high environmental temperatures].

PubMed

Bobrov, A F; Kuznets, E I

1995-01-01

The paper deals with the physiological classification of human thermal states in a hot environment. A review of the basic systems of classifications of thermal states is given, their main drawbacks are discussed. On the basis of human functional state research in a broad range of environmental temperatures the system of evaluation and classification of human thermal states is proposed. New integral one-dimensional multi-parametric criteria for evaluation are used. For the development of these criteria methods of factor, cluster and canonical correlation analyses are applied. Stochastic nomograms capable of identification of human thermal state for different intensity of influence are given. In this case evaluation of intensity is estimated according to one-dimensional criteria taking into account environmental temperature, physical load and time of man's staying in overheating conditions.

The vaginal microbiota, host defence and reproductive physiology.

PubMed

Smith, Steven B; Ravel, Jacques

2017-01-15

The interaction between the human host and the vaginal microbiota is highly dynamic. Major changes in the vaginal physiology and microbiota over a woman's lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy, while daily fluctuations in microbial composition observed through culture-independent studies are more likely to be the results of daily life activities and behaviours. The vaginal microbiota of reproductive-aged women is largely made up of at least five different community state types. Four of these community state types are dominated by lactic-acid producing Lactobacillus spp. while the fifth is commonly composed of anaerobes and strict anaerobes and is sometimes associated with vaginal symptoms. The production of lactic acid has been associated with contributing to the overall health of the vagina due to its direct and indirect effects on pathogens and host defence. Some species associated with non-Lactobacillus vaginal microbiota may trigger immune responses as well as degrade the host mucosa, processes that ultimately increase susceptibility to infections and contribute to negative reproductive outcomes such as infertility and preterm birth. Further studies are needed to better understand the functional underpinnings of how the vaginal microbiota affect host physiology but also how host physiology affects the vaginal microbiota. Understanding this fine-tuned interaction is key to maintaining women's reproductive health. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Micro-patterned graphene-based sensing skins for human physiological monitoring

NASA Astrophysics Data System (ADS)

Wang, Long; Loh, Kenneth J.; Chiang, Wei-Hung; Manna, Kausik

2018-03-01

Ultrathin, flexible, conformal, and skin-like electronic transducers are emerging as promising candidates for noninvasive and nonintrusive human health monitoring. In this work, a wearable sensing membrane is developed by patterning a graphene-based solution onto ultrathin medical tape, which can then be attached to the skin for monitoring human physiological parameters and physical activity. Here, the sensor is validated for monitoring finger bending/movements and for recognizing hand motion patterns, thereby demonstrating its future potential for evaluating athletic performance, physical therapy, and designing next-generation human-machine interfaces. Furthermore, this study also quantifies the sensor’s ability to monitor eye blinking and radial pulse in real-time, which can find broader applications for the healthcare sector. Overall, the printed graphene-based sensing skin is highly conformable, flexible, lightweight, nonintrusive, mechanically robust, and is characterized by high strain sensitivity.

Applying systems biology methods to the study of human physiology in extreme environments

PubMed Central

2013-01-01

Systems biology is defined in this review as ‘an iterative process of computational model building and experimental model revision with the aim of understanding or simulating complex biological systems’. We propose that, in practice, systems biology rests on three pillars: computation, the omics disciplines and repeated experimental perturbation of the system of interest. The number of ethical and physiologically relevant perturbations that can be used in experiments on healthy humans is extremely limited and principally comprises exercise, nutrition, infusions (e.g. Intralipid), some drugs and altered environment. Thus, we argue that systems biology and environmental physiology are natural symbionts for those interested in a system-level understanding of human biology. However, despite excellent progress in high-altitude genetics and several proteomics studies, systems biology research into human adaptation to extreme environments is in its infancy. A brief description and overview of systems biology in its current guise is given, followed by a mini review of computational methods used for modelling biological systems. Special attention is given to high-altitude research, metabolic network reconstruction and constraint-based modelling. PMID:23849719

Early life exposure to artificial light at night affects the physiological condition: An experimental study on the ecophysiology of free-living nestling songbirds.

PubMed

Raap, Thomas; Casasole, Giulia; Pinxten, Rianne; Eens, Marcel

2016-11-01

Light pollution or artificial light at night (ALAN) is increasingly recognised to be an important anthropogenic environmental pressure on wildlife, affecting animal behaviour and physiology. Early life experiences are extremely important for the development, physiological status and health of organisms, and as such, early exposure to artificial light may have detrimental consequences for organism fitness. We experimentally manipulated the light environment of free-living great tit nestlings (Parus major), an important model species in evolutionary and environmental research. Haptoglobin (Hp) and nitric oxide (NOx), as important indicators of immunity, health, and physiological condition, were quantified in nestlings at baseline (13 days after hatching) and after a two night exposure to ALAN. We found that ALAN increased Hp and decreased NOx. ALAN may increase stress and oxidative stress and reduce melatonin which could subsequently lead to increased Hp and decreased NOx. Haptoglobin is part of the immune response and mounting an immune response is costly in energy and resources and, trade-offs are likely to occur with other energetically demanding tasks, such as survival or reproduction. Acute inhibition of NOx may have a cascading effect as it also affects other physiological aspects and may negatively affect immunocompetence. The consequences of the observed effects on Hp and NOx remain to be examined. Our study provides experimental field evidence that ALAN affects nestlings' physiology during development and early life exposure to ALAN could therefore have long lasting effects throughout adulthood. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knowledge on the subject of human physiology among Polish high school students--a cross-sectional study.

PubMed

Zwinczewska, Helena; Rozwadowska, Joanna; Traczyk, Anna; Majda, Szymon; Wysocki, Michał; Grabowski, Kamil; Kopeć, Sylwia; Głowacki, Roman; Węgrzyn, Katarzyna; Tomaszewski, Krzysztof A; Walocha, Jerzy A

2014-01-01

In most cases the only knowledge an individual will receive with regards to their own body and its proper functioning is during their high school education. The aim of this study was to evaluate high school students' knowledge about basic physiology. The research was carried out in five, randomly chosen high schools in Krakow, Poland. Young people in the age of 17-19 years were asked to fill in the questionnaire designed by the authors. The first part of the survey included personal data. The second part contained 20 close-ended questions assessing students' knowledge about the basics of human physiology. Question difficulty varied from easy through average, and up to difficult. The maximum number of points to achieve was 20. One-thousand-and eighty-three (out of 1179 invited--91.86%) Polish high school students (63.25% female) filled in a 20-item questionnaire constructed by the authors regarding basic human physiology. The mean age of the group was 17.66 ± 0.80 years. The mean score among the surveyed was 10.15 ± 3.48 (range 0-20). Only 26.04% of students achieved a grade of 60% or more, and only one person obtained the highest possible score. Females achieved significantly better scores than males (10.49 ± 3.38 vs. 9.56 ± 3.56; p < 0.0001). Pupils in their second year who were in the process of studying physiology, obtained better results than those in their third year who had already finished the biology course (10.70 ± 3.27 vs. 9.81 ± 3.74 respectively; p < 0.0001) and those in their first year who did not yet study human physiology (10.70 ± 3.27 vs. 9.63 ± 2.74 respectively; p = 0.003). Over 23% of students did not know that mature red blood cells do not have cell nuclei and a similar number of them answered that humans have 500,000 erythrocytes in 1 mm3 of blood. Over 32% believed that plasma does not participate in the transport of respiratory gases, and 31% believed that endocrine glands secrete hormones within their immediate vicinity and into the

An integrated approach to develop, validate and operate thermo-physiological human simulator for the development of protective clothing.

PubMed

Psikuta, Agnes; Koelblen, Barbara; Mert, Emel; Fontana, Piero; Annaheim, Simon

2017-12-07

Following the growing interest in the further development of manikins to simulate human thermal behaviour more adequately, thermo-physiological human simulators have been developed by coupling a thermal sweating manikin with a thermo-physiology model. Despite their availability and obvious advantages, the number of studies involving these devices is only marginal, which plausibly results from the high complexity of the development and evaluation process and need of multi-disciplinary expertise. The aim of this paper is to present an integrated approach to develop, validate and operate such devices including technical challenges and limitations of thermo-physiological human simulators, their application and measurement protocol, strategy for setting test scenarios, and the comparison to standard methods and human studies including details which have not been published so far. A physical manikin controlled by a human thermoregulation model overcame the limitations of mathematical clothing models and provided a complementary method to investigate thermal interactions between the human body, protective clothing, and its environment. The opportunities of these devices include not only realistic assessment of protective clothing assemblies and equipment but also potential application in many research fields ranging from biometeorology, automotive industry, environmental engineering, and urban climate to clinical and safety applications.

Physiological Health Challenges for Human Missions to Mars

NASA Technical Reports Server (NTRS)

Norsk, Peter

2015-01-01

During the next decades, manned space missions are expected to be aiming at the Lagrange points, near Earth asteroids, and Mars flyby and/or landing. The question is therefore: Are we ready to go? To answer this with a yes, we are currently using the International Space Station to develop an integrated human physiological countermeasure suite. The integrated countermeasure suite will most likely encounter: 1) Exercise devices for aerobic, dynamic and resistive exercise training; 2) sensory-motor computer training programs and anti-motion sickness medication for preparing EVAs and G-transitions; 3) lower limb bracelets for preventing and/or treating the VIIP (vision impairment and intracranial pressure) syndrome; 4) nutritional components for maintenance of bone, muscle, the cardiovascular system and preventing oxidative stress and damage and immune deficiencies (e. g. omega-3 fatty acids, PRO/K, anti-oxidants and less salt and iron); 5) bisphosphonates for preventing bone degradation.; 6) lower body compression garment and oral salt and fluid loading for landing on a planetary surface to combat orthostatic intolerance; 7) laboratory analysis equipment for individualized monitoring of biomarkers in blood, urine and saliva for estimation of health status in; 8) advanced ultrasound techniques for monitoring bone and cardiovascular health; and 9) computer modeling programs for individual health status assessments of efficiency and subsequent adjustments of countermeasures. In particular for future missions into deep space, we are concerned with the synergistic effects of weightlessness, radiation, operational constraints and other spaceflight environmental factors. Therefore, increased collaboration between physiological, behavioral, radiation and space vehicle design disciplines are strongly warranted. Another venue we are exploring in NASA's Human Research Program is the usefulness of artificial gravity for mitigating the health risks of long duration weightlessness.

Building an experimental model of the human body with non-physiological parameters

PubMed Central

Labuz, Joseph M.; Moraes, Christopher; Mertz, David R.; Leung, Brendan M.; Takayama, Shuichi

2017-01-01

New advances in engineering and biomedical technology have enabled recent efforts to capture essential aspects of human physiology in microscale, in-vitro systems. The application of these advances to experimentally model complex processes in an integrated platform — commonly called a ‘human-on-a-chip (HOC)’ — requires that relevant compartments and parameters be sized correctly relative to each other and to the system as a whole. Empirical observation, theoretical treatments of resource distribution systems and natural experiments can all be used to inform rational design of such a system, but technical and fundamental challenges (e.g. small system blood volumes and context-dependent cell metabolism, respectively) pose substantial, unaddressed obstacles. Here, we put forth two fundamental principles for HOC design: inducing in-vivo-like cellular metabolic rates is necessary and may be accomplished in-vitro by limiting O2 availability and that the effects of increased blood volumes on drug concentration can be mitigated through pharmacokinetics-based treatments of solute distribution. Combining these principles with natural observation and engineering workarounds, we derive a complete set of design criteria for a practically realizable, physiologically faithful, five-organ millionth-scale (× 10−6) microfluidic model of the human body. PMID:28713851

Physiological basis for human autonomic rhythms

NASA Technical Reports Server (NTRS)

Eckberg, D. L.

2000-01-01

Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

An Individualized, Perception-Based Protocol to Investigate Human Physiological Responses to Cooling

PubMed Central

Coolbaugh, Crystal L.; Bush, Emily C.; Galenti, Elizabeth S.; Welch, E. Brian; Towse, Theodore F.

2018-01-01

Cold exposure, a known stimulant of the thermogenic effects of brown adipose tissue (BAT), is the most widely used method to study BAT physiology in adult humans. Recently, individualized cooling has been recommended to standardize the physiological cold stress applied across participants, but critical experimental details remain unclear. The purpose of this work was to develop a detailed methodology for an individualized, perception-based protocol to investigate human physiological responses to cooling. Participants were wrapped in two water-circulating blankets and fitted with skin temperature probes to estimate BAT activity and peripheral vasoconstriction. We created a thermoesthesia graphical user interface (tGUI) to continuously record the subject's perception of cooling and shivering status during the cooling protocol. The protocol began with a 15 min thermoneutral phase followed by a series of 10 min cooling phases and concluded when sustained shivering (>1 min duration) occurred. Researchers used perception of cooling feedback (tGUI ratings) to manually adjust and personalize the water temperature at each cooling phase. Blanket water temperatures were recorded continuously during the protocol. Twelve volunteers (ages: 26.2 ± 1.4 years; 25% female) completed a feasibility study to evaluate the proposed protocol. Water temperature, perception of cooling, and shivering varied considerably across participants in response to cooling. Mean clavicle skin temperature, a surrogate measure of BAT activity, decreased (−0.99°C, 95% CI: −1.7 to −0.25°C, P = 0.16) after the cooling protocol, but an increase in supraclavicular skin temperature was observed in 4 participants. A strong positive correlation was also found between thermoesthesia and peripheral vasoconstriction (ρ = 0.84, P < 0.001). The proposed individualized, perception-based protocol therefore has potential to investigate the physiological responses to cold stress applied across populations with

Toward Scalable Trustworthy Computing Using the Human-Physiology-Immunity Metaphor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hively, Lee M; Sheldon, Frederick T

The cybersecurity landscape consists of an ad hoc patchwork of solutions. Optimal cybersecurity is difficult for various reasons: complexity, immense data and processing requirements, resource-agnostic cloud computing, practical time-space-energy constraints, inherent flaws in 'Maginot Line' defenses, and the growing number and sophistication of cyberattacks. This article defines the high-priority problems and examines the potential solution space. In that space, achieving scalable trustworthy computing and communications is possible through real-time knowledge-based decisions about cyber trust. This vision is based on the human-physiology-immunity metaphor and the human brain's ability to extract knowledge from data and information. The article outlines future steps towardmore » scalable trustworthy systems requiring a long-term commitment to solve the well-known challenges.« less

Environmental and Physiological Factors Affect Football Head Impact Biomechanics.

PubMed

Mihalik, Jason P; Sumrall, Adam Z; Yeargin, Susan W; Guskiewicz, Kevin M; King, Kevin B; Trulock, Scott C; Shields, Edgar W

2017-10-01

Recent anecdotal trends suggest a disproportionate number of head injuries in collegiate football players occur during preseason football camp. In warmer climates, this season also represents the highest risk for heat-related illness among collegiate football players. Because concussion and heat illnesses share many common symptoms, we need 1) to understand if environmental conditions, body temperature, and hydration status affect head impact biomechanics; and 2) to determine if an in-helmet thermistor could provide a valid measure of gastrointestinal temperature. A prospective cohort of 18 Division I college football players (age, 21.1 ± 1.4 yr; height, 187.7 ± 6.6 cm; mass, 114.5 ± 23.4 kg). Data were collected during one control and three experimental sessions. During each session, the Head Impact Telemetry System recorded head impact biomechanics (linear acceleration, rotational acceleration, and severity profile) and in-helmet temperature. A wet bulb globe device recorded environmental conditions, and CorTemp™ Ingestible Core Body Temperature Sensors recorded gastrointestinal temperature. Our findings suggest that linear acceleration (P = 0.57), rotational acceleration (P = 0.16), and Head Impact Technology severity profile (P = 0.33) are not influenced by environmental or physiological conditions. We did not find any single or combination of predictors for impact severity. Rotational acceleration was approaching significance between our early experimental sessions when compared with our control session. More research should be conducted to better understand if rotational accelerations are a component of impact magnitudes that are affected due to changes in environmental conditions, body temperature, and hydration status.

Devices for noninvasive transcranial electrostimulation of the brain endorphinergic system: application for improvement of human psycho-physiological status.

PubMed

Lebedev, Valery P; Malygin, A V; Kovalevski, A V; Rychkova, S V; Sisoev, V N; Kropotov, S P; Krupitski, E M; Gerasimova, L I; Glukhov, D V; Kozlowski, G P

2002-03-01

It is well known that deficit of endorphins plays an important role in disturbances of human psycho-physiological status. Previously, we revealed that brain endorphinergic structures have quasiresonance characteristics. On the basis of these data, a method of activation of the brain endorphinergic structures by means of noninvasive and rather selective transcranial electrostimulation (TES) as a kind of functional electrical stimulation (FES) was elaborated. New models of TES devices (TRANSAIR) were developed for indoor and outdoor usage. To increase the efficacy of TES, the frequency modulation according to normal distribution in the limits of the quasiresonance characteristics was put into operation. The blind and placebo-controlled (passive and active placebo) study was produced to estimate the TES effects on stress events and accompanied psycho-physiological and autonomic disturbances of different intensities on volunteers and patients in the following groups: everyday stress and fatigue; stress in regular military service and in field conditions; stress in the relatives of those lost in mass disaster; posttraumatic stress (thermal burns); and affective disorders in a postabstinence period. Some subjective verbal and nonverbal tests and objective tests (including heart rate variability) were used for estimation of the initial level of psycho-physiological status, which changes after TES sessions. It was demonstrated that fatigue, stress, and other accompanied psycho-physiological disturbances were significantly improved or abolished after 2-5 TES sessions. The TES effects were more pronounced in cases of heavier disturbances. In conclusion, activation of the brain endorphinergic structures by TES is an effective homeostatic method of FES that sufficiently improves quality of life.

Sex differences in physiological and affective responses to stress in remitted depression.

PubMed

Bagley, Sara L; Weaver, Terri L; Buchanan, Tony W

2011-08-03

Major depressive disorder (MDD) is associated with alterations in stress physiology. Severe melancholic depression is characterized by hypercortisolism, but community dwelling mildly depressed individuals and those with remitted MDD have shown reduced or normal reactivity to stress. There are also pronounced sex differences both in the incidence of MDD and in stress reactivity. To explore the relationships among depression history, sex differences, and stress, we examined stress reactivity in people with and without a history of MDD. Twenty-two participants with remitted MDD (12 men and 10 women) and 36 never depressed comparison participants (22 men and 14 women) participated in the study. Cortisol and alpha-amylase (sAA) were sampled from saliva before, 10 min after, and 30 min after the Trier Social Stress Test (TSST). Participants filled out the Positive Affect Negative Affect Schedule (PANAS) before and after they underwent the TSST. Women with remitted MDD showed reduced cortisol response to the TSST compared with the never MDD women, while men with remitted MDD showed comparable cortisol reactivity to the never depressed men. The groups did not differ on sAA reactivity to stress. The remitted MDD group (overall and men and women separately) reported greater negative affect both before and after stress compared to the never depressed group. Women from both groups reported greater post-stress negative affect than men. In contrast, men from both groups reported higher positive affect before and after stress than women. Given that the sex difference findings were not dependent on depression history, self-reported affective differences in response to stress may predate depressive symptoms and contribute to sex differences in depression incidence. Copyright © 2011 Elsevier Inc. All rights reserved.

The effect of choice on the physiology of emotion: An affective startle modulation study

PubMed Central

Genevsky, Alexander; Gard, David E.

2014-01-01

The affective startle modulation task has been an important measure in understanding physiological aspects of emotion and motivational responses. Research utilizing this method has relied primarily on a ‘passive’ viewing paradigm, which stands in contrast to everyday life where much of emotion and motivation involves some active choice or agency. The present study investigated the role of choice on the physiology of emotion. Eighty-four participants were randomized into ‘choice’ (n=44) or ‘no-choice’ (n=40) groups distinguished by the ability to choose between stimuli. EMG eye blink responses were recorded in both anticipation and stimulus viewing. Results indicated a significant attenuation of the startle magnitude in choice condition trials (relative to no-choice) across all picture categories and probe times. We interpret these findings as an indication that the act of choice may decrease one’s defensive response, or conversely, lacking choice may heighten the defensive response. Implications for future research are discussed. PMID:22285891

The effect of choice on the physiology of emotion: an affective startle modulation study.

PubMed

Genevsky, Alexander; Gard, David E

2012-04-01

The affective startle modulation task has been an important measure in understanding physiological aspects of emotion and motivational responses. Research utilizing this method has relied primarily on a 'passive' viewing paradigm, which stands in contrast to everyday life where much of emotion and motivation involves some active choice or agency. The present study investigated the role of choice on the physiology of emotion. Eighty-four participants were randomized into 'choice' (n=44) or 'no-choice' (n=40) groups distinguished by the ability to choose between stimuli. EMG eye blink responses were recorded in both anticipation and stimulus viewing. Results indicated a significant attenuation of the startle magnitude in choice condition trials (relative to no-choice) across all picture categories and probe times. We interpret these findings as an indication that the act of choice may decrease one's defensive response, or conversely, lacking choice may heighten the defensive response. Implications for future research are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

Major component analysis of dynamic networks of physiologic organ interactions

NASA Astrophysics Data System (ADS)

Liu, Kang K. L.; Bartsch, Ronny P.; Ma, Qianli D. Y.; Ivanov, Plamen Ch

2015-09-01

The human organism is a complex network of interconnected organ systems, where the behavior of one system affects the dynamics of other systems. Identifying and quantifying dynamical networks of diverse physiologic systems under varied conditions is a challenge due to the complexity in the output dynamics of the individual systems and the transient and nonlinear characteristics of their coupling. We introduce a novel computational method based on the concept of time delay stability and major component analysis to investigate how organ systems interact as a network to coordinate their functions. We analyze a large database of continuously recorded multi-channel physiologic signals from healthy young subjects during night-time sleep. We identify a network of dynamic interactions between key physiologic systems in the human organism. Further, we find that each physiologic state is characterized by a distinct network structure with different relative contribution from individual organ systems to the global network dynamics. Specifically, we observe a gradual decrease in the strength of coupling of heart and respiration to the rest of the network with transition from wake to deep sleep, and in contrast, an increased relative contribution to network dynamics from chin and leg muscle tone and eye movement, demonstrating a robust association between network topology and physiologic function.

Effects of foliage plants on human physiological and psychological responses at different temperatures

NASA Astrophysics Data System (ADS)

Jumeno, Desto; Matsumoto, Hiroshi

2015-02-01

Escalation of task demands and time pressures tends to make a worker run into work stress, which leads to mental fatigue and depression. The mental fatigue can be reduced when attention capacity is restored. Nature can serve as a source of fascination which can restore the attention capacity. People bring plants indoors so they can experience nature in their workplace. The stress and fatigue are also affected by air temperatures. The increase or decrease of temperatures from the comfort zone may induce the stress and fatigue. The objective of this study is to investigate the intervention of using foliage plants placed inside a building at different air temperature levels. The effects of foliage plants on human stress and fatigue were measured by human physiological responses such as heart rate, amylase level, electroencephalography (EEG), and the secondary task-reaction time. Several different tasks, namely typing, math and logical sequences are included in the investigation of these studies. Fifteen subjects, with the age ranged from 22 to 38 years old have participated in the study using within subject design. From the study, it is revealed that the presence of foliage plants at several temperatures have different effects on meditation, secondary task reaction time and typing accuracy. This study also revealed that the presence of plants on several types of tasks has different effects of attention which are useful for increasing work performance.

Audio-Tutorial Project: An Audio-Tutorial Approach to Human Anatomy and Physiology.

ERIC Educational Resources Information Center

Muzio, Joseph N.; And Others

A two course sequence on human anatomy and physiology using the audiotutorial method of instruction was developed for use by nursing students and other students in the health or medical fields at the Kingsborough Community College in New York. The project was motivated by the problems of often underprepared students coming to learn a new field and…

An Investigative Laboratory Course in Human Physiology Using Computer Technology and Collaborative Writing

ERIC Educational Resources Information Center

FitzPatrick, Kathleen A.

2004-01-01

Active investigative student-directed experiences in laboratory science are being encouraged by national science organizations. A growing body of evidence from classroom assessment supports their effectiveness. This study describes four years of implementation and assessment of an investigative laboratory course in human physiology for 65…

Chewing Over Physiology Integration

ERIC Educational Resources Information Center

Abdulkader, Fernando; Azevedo-Martins, Anna Karenina; de Arcisio Miranda, Manoel; Brunaldi, Kellen

2005-01-01

An important challenge for both students and teachers of physiology is to integrate the differentareas in which physiological knowledge is didactically divided. In developing countries, such an issue is even more demanding, because budget restrictions often affect the physiology program with laboratory classes being the first on the list when it…

An integrated approach to develop, validate and operate thermo-physiological human simulator for the development of protective clothing

PubMed Central

PSIKUTA, Agnes; KOELBLEN, Barbara; MERT, Emel; FONTANA, Piero; ANNAHEIM, Simon

2017-01-01

Following the growing interest in the further development of manikins to simulate human thermal behaviour more adequately, thermo-physiological human simulators have been developed by coupling a thermal sweating manikin with a thermo-physiology model. Despite their availability and obvious advantages, the number of studies involving these devices is only marginal, which plausibly results from the high complexity of the development and evaluation process and need of multi-disciplinary expertise. The aim of this paper is to present an integrated approach to develop, validate and operate such devices including technical challenges and limitations of thermo-physiological human simulators, their application and measurement protocol, strategy for setting test scenarios, and the comparison to standard methods and human studies including details which have not been published so far. A physical manikin controlled by a human thermoregulation model overcame the limitations of mathematical clothing models and provided a complementary method to investigate thermal interactions between the human body, protective clothing, and its environment. The opportunities of these devices include not only realistic assessment of protective clothing assemblies and equipment but also potential application in many research fields ranging from biometeorology, automotive industry, environmental engineering, and urban climate to clinical and safety applications. PMID:28966294

Human physiological responses to wooden indoor environment.

PubMed

Zhang, Xi; Lian, Zhiwei; Wu, Yong

2017-05-15

Previous studies are mainly focused on non-wooden environments, whereas few are concerned with wooden ones. How wooden indoor environments impact the physiology of the occupants is still unclear. The purpose of this study was to explore the distinct physiological responses to wooden and non-wooden indoor environments, assessed by physiological parameters tests including blood pressure, electrocardiogram measurements, electro-dermal activity, oxyhemoglobin saturation, skin temperature, and near distance vision. Twenty healthy adults participated in this experiment, and their physiological responses were evaluated in a 90minute investigation. The results illustrated that; less tension and fatigue were generated in the wooden rooms than in the non-wooden rooms when the participants did their work. In addition, the study also found that the wooden environments benefit the autonomic nervous system, respiratory system, and visual system. Moreover, wooden rooms play a valuable role in physiological regulation and ease function especially after a consecutive period of work. These results provide an experimental basis to support that wooden environment is beneficial to indoor occupants than the non-wooden indoor environment. Copyright © 2017 Elsevier Inc. All rights reserved.

Physiological markers of motor inhibition during human behavior

PubMed Central

Duque, Julie; Greenhouse, Ian; Labruna, Ludovica; Ivry, Richard B.

2017-01-01

Transcranial magnetic stimulation (TMS) studies in humans have shown that many behaviors engage processes that suppress excitability within the corticospinal tract. Inhibition of the motor output pathway has been extensively studied in the context of action stopping, where a planned movement needs to be abruptly aborted. Recent TMS work has also revealed markers of motor inhibition during the preparation of movement. Here, we review the evidence for motor inhibition during action stopping and action preparation, focusing on studies that have used TMS to monitor changes in the excitability of the corticospinal pathway. We discuss how these physiological results have motivated theoretical models of how the brain selects actions, regulates movement initiation and execution, and switches from one state to another. PMID:28341235

Examination of Duct Physiology in the Human Mammary Gland

PubMed Central

Mills, Dixie; Gomberawalla, Ameer; Gordon, Eva J.; Tondre, Julie; Nejad, Mitra; Nguyen, Tinh; Pogoda, Janice M.; Rao, Jianyu; Chatterton, Robert; Henning, Susanne; Love, Susan M.

2016-01-01

Background The human breast comprise several ductal systems, or lobes, which contain a small amount of fluid containing cells, hormones, proteins and metabolites. The complex physiology of these ducts is likely a contributing factor to the development of breast cancer, especially given that the vast majority of breast cancers begin in a single lobular unit. Methods We examined the levels of total protein, progesterone, estradiol, estrone sulfate, dehydroepiandrosterone sulfate, and macrophages in ductal fluid samples obtained from 3 ducts each in 78 women, sampled twice over a 6 month period. Samples were processed for both cytological and molecular analysis. Intraclass correlation coefficients and mixed models were utilized to identify significant data. Results We found that the levels of these ductal fluid components were generally uncorrelated among ducts within a single breast and over time, suggesting that each lobe within the breast has a distinct physiology. However, we also found that estradiol was more correlated in women who were nulliparous or produced nipple aspirate fluid. Conclusions Our results provide evidence that the microenvironment of any given lobular unit is unique to that individual unit, findings that may provide clues about the initiation and development of ductal carcinomas. PMID:27073976

Physiological determinants of human acute hypoxia tolerance.

DOT National Transportation Integrated Search

2013-11-01

AbstractIntroduction. We investigated possible physiological determinants of variability in hypoxia tolerance in subjects given a 5-minute normobaric exposure to 25,000 ft equivalent. Physiological tolerance to hypoxia was defined as the magnitude of...

Singular value decomposition based feature extraction technique for physiological signal analysis.

PubMed

Chang, Cheng-Ding; Wang, Chien-Chih; Jiang, Bernard C

2012-06-01

Multiscale entropy (MSE) is one of the popular techniques to calculate and describe the complexity of the physiological signal. Many studies use this approach to detect changes in the physiological conditions in the human body. However, MSE results are easily affected by noise and trends, leading to incorrect estimation of MSE values. In this paper, singular value decomposition (SVD) is adopted to replace MSE to extract the features of physiological signals, and adopt the support vector machine (SVM) to classify the different physiological states. A test data set based on the PhysioNet website was used, and the classification results showed that using SVD to extract features of the physiological signal could attain a classification accuracy rate of 89.157%, which is higher than that using the MSE value (71.084%). The results show the proposed analysis procedure is effective and appropriate for distinguishing different physiological states. This promising result could be used as a reference for doctors in diagnosis of congestive heart failure (CHF) disease.

Physiologically relevant organs on chips

PubMed Central

Yum, Kyungsuk; Hong, Soon Gweon; Lee, Luke P.

2015-01-01

Recent advances in integrating microengineering and tissue engineering have generated promising microengineered physiological models for experimental medicine and pharmaceutical research. Here we review the recent development of microengineered physiological systems, or organs on chips, that reconstitute the physiologically critical features of specific human tissues and organs and their interactions. This technology uses microengineering approaches to construct organ-specific microenvironments, reconstituting tissue structures, tissue–tissue interactions and interfaces, and dynamic mechanical and biochemical stimuli found in specific organs, to direct cells to assemble into functional tissues. We first discuss microengineering approaches to reproduce the key elements of physiologically important, dynamic mechanical microenvironments, biochemical microenvironments, and microarchitectures of specific tissues and organs in microfluidic cell culture systems. This is followed by examples of microengineered individual organ models that incorporate the key elements of physiological microenvironments into single microfluidic cell culture systems to reproduce organ-level functions. Finally, microengineered multiple organ systems that simulate multiple organ interactions to better represent human physiology, including human responses to drugs, is covered in this review. This emerging organs-on-chips technology has the potential to become an alternative to 2D and 3D cell culture and animal models for experimental medicine, human disease modeling, drug development, and toxicology. PMID:24357624

Wearable carbon nanotube-based fabric sensors for monitoring human physiological performance

NASA Astrophysics Data System (ADS)

Wang, Long; Loh, Kenneth J.

2017-05-01

A target application of wearable sensors is to detect human motion and to monitor physical activity for improving athletic performance and for delivering better physical therapy. In addition, measuring human vital signals (e.g., respiration rate and body temperature) provides rich information that can be used to assess a subject’s physiological or psychological condition. This study aims to design a multifunctional, wearable, fabric-based sensing system. First, carbon nanotube (CNT)-based thin films were fabricated by spraying. Second, the thin films were integrated with stretchable fabrics to form the fabric sensors. Third, the strain and temperature sensing properties of sensors fabricated using different CNT concentrations were characterized. Furthermore, the sensors were demonstrated to detect human finger bending motions, so as to validate their practical strain sensing performance. Finally, to monitor human respiration, the fabric sensors were integrated with a chest band, which was directly worn by a human subject. Quantification of respiration rates were successfully achieved. Overall, the fabric sensors were characterized by advantages such as flexibility, ease of fabrication, lightweight, low-cost, noninvasiveness, and user comfort.

Conformational ensemble of human α-synuclein physiological form predicted by molecular simulations.

PubMed

Rossetti, G; Musiani, F; Abad, E; Dibenedetto, D; Mouhib, H; Fernandez, C O; Carloni, P

2016-02-17

We perform here enhanced sampling simulations of N-terminally acetylated human α-synuclein, an intrinsically disordered protein involved in Parkinson's disease. The calculations, consistent with experiments, suggest that the post-translational modification leads to the formation of a transient amphipathic α-helix. The latter, absent in the non-physiological form, alters protein dynamics at the N-terminal and intramolecular interactions.

On making nursing undergraduate human reproductive physiology content meaningful and relevant: discussion of human pleasure in its biological context.

PubMed

McClusky, Leon Mendel

2012-01-01

The traditional presentation of the Reproductive Physiology component in an Anatomy and Physiology course to nursing undergraduates focuses on the broad aspects of hormonal regulation of reproduction and gonadal anatomy, with the role of the higher centres of the brain omitted. An introductory discussion is proposed which could precede the lectures on the reproductive organs. The discussion gives an overview of the biological significance of human pleasure, the involvement of the neurotransmitter dopamine, and the role of pleasure in the survival of the individual and even species. Pleasure stimuli (positive and negative) and the biological significance of naturally-induced pleasurable experiences are briefly discussed in the context of reproduction and the preservation of genetic material with an aim to foster relevancy between subject material and human behaviour in any type of society. The tenderness of this aspect of the human existence is well-understood because of its invariable association with soul-revealing human expressions such as love, infatuation, sexual flirtations, all of which are underpinned by arousal, desire and/or pleasure. Assuming that increased knowledge correlates with increased confidence, the proposed approach may provide the nurse with an adequate knowledge base to overcome well-known barriers in communicating with their patients about matters of sexual health and intimacy. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nutritional physiology and ecology of wildlife in a changing world.

PubMed

Birnie-Gauvin, Kim; Peiman, Kathryn S; Raubenheimer, David; Cooke, Steven J

2017-01-01

Over the last century, humans have modified landscapes, generated pollution and provided opportunities for exotic species to invade areas where they did not evolve. In addition, humans now interact with animals in a growing number of ways (e.g. ecotourism). As a result, the quality (i.e. nutrient composition) and quantity (i.e. food abundance) of dietary items consumed by wildlife have, in many cases, changed. We present representative examples of the extent to which vertebrate foraging behaviour, food availability (quantity and quality) and digestive physiology have been modified due to human-induced environmental changes and human activities. We find that these effects can be quite extensive, especially as a result of pollution and human-provisioned food sources (despite good intentions). We also discuss the role of nutrition in conservation practices, from the perspective of both in situ and ex situ conservation. Though we find that the changes in the nutritional ecology and physiology of wildlife due to human alterations are typically negative and largely involve impacts on foraging behaviour and food availability, the extent to which these will affect the fitness of organisms and result in evolutionary changes is not clearly understood, and requires further investigation.

Organ-specific physiological responses to acute physical exercise and long-term training in humans.

PubMed

Heinonen, Ilkka; Kalliokoski, Kari K; Hannukainen, Jarna C; Duncker, Dirk J; Nuutila, Pirjo; Knuuti, Juhani

2014-11-01

Virtually all tissues in the human body rely on aerobic metabolism for energy production and are therefore critically dependent on continuous supply of oxygen. Oxygen is provided by blood flow, and, in essence, changes in organ perfusion are also closely associated with alterations in tissue metabolism. In response to acute exercise, blood flow is markedly increased in contracting skeletal muscles and myocardium, but perfusion in other organs (brain and bone) is only slightly enhanced or is even reduced (visceral organs). Despite largely unchanged metabolism and perfusion, repeated exposures to altered hemodynamics and hormonal milieu produced by acute exercise, long-term exercise training appears to be capable of inducing effects also in tissues other than muscles that may yield health benefits. However, the physiological adaptations and driving-force mechanisms in organs such as brain, liver, pancreas, gut, bone, and adipose tissue, remain largely obscure in humans. Along these lines, this review integrates current information on physiological responses to acute exercise and to long-term physical training in major metabolically active human organs. Knowledge is mostly provided based on the state-of-the-art, noninvasive human imaging studies, and directions for future novel research are proposed throughout the review. ©2014 Int. Union Physiol. Sci./Am. Physiol. Soc.

Delayed system response times affect immediate physiology and the dynamics of subsequent button press behavior.

PubMed

Kohrs, Christin; Hrabal, David; Angenstein, Nicole; Brechmann, André

2014-11-01

System response time research is an important issue in human-computer interactions. Experience with technical devices and general rules of human-human interactions determine the user's expectation, and any delay in system response time may lead to immediate physiological, emotional, and behavioral consequences. We investigated such effects on a trial-by-trial basis during a human-computer interaction by measuring changes in skin conductance (SC), heart rate (HR), and the dynamics of button press responses. We found an increase in SC and a deceleration of HR for all three delayed system response times (0.5, 1, 2 s). Moreover, the data on button press dynamics was highly informative since subjects repeated a button press with more force in response to delayed system response times. Furthermore, the button press dynamics could distinguish between correct and incorrect decisions and may thus even be used to infer the uncertainty of a user's decision. Copyright © 2014 Society for Psychophysiological Research.

Physiological role of urothelial cancer-associated one long noncoding RNA in human skeletogenic cell differentiation.

PubMed

Ishikawa, Takanori; Nishida, Takashi; Ono, Mitsuaki; Takarada, Takeshi; Nguyen, Ha Thi; Kurihara, Shinnosuke; Furumatsu, Takayuki; Murase, Yurika; Takigawa, Masaharu; Oohashi, Toshitaka; Kamioka, Hiroshi; Kubota, Satoshi

2018-06-01

A vast number of long-noncoding RNAs (lncRNA) are found expressed in human cells, which RNAs have been developed along with human evolution. However, the physiological functions of these lncRNAs remain mostly unknown. In the present study, we for the first time uncovered the fact that one of such lncRNAs plays a significant role in the differentiation of chondrocytes and, possibly, of osteoblasts differentiated from mesenchymal stem cells, which cells eventually construct the human skeleton. The urothelial cancer-associated 1 (UCA1) lncRNA is known to be associated with several human malignancies. Firstly, we confirmed that UCA1 was expressed in normal human chondrocytes, as well as in a human chondrocytic cell line; whereas it was not detected in human bone marrow mesenchymal stem cells (hBMSCs). Of note, although UCA1 expression was undetectable in hBMSCs, it was markedly induced along with the differentiation toward chondrocytes, suggesting its critical role in chondrogenesis. Consistent with this finding, silencing of the UCA1 gene significantly repressed the expression of chondrogenic genes in human chondrocytic cells. UCA1 gene silencing and hyper-expression also had a significant impact on the osteoblastic phenotype in a human cell line. Finally, forced expression of UCA1 in a murine chondrocyte precursor, which did not possess a UCA1 gene, overdrove its differentiation into chondrocytes. These results indicate a physiological and important role of this lncRNA in the skeletal development of humans, who require more sustained endochondral ossification and osteogenesis than do smaller vertebrates. © 2017 Wiley Periodicals, Inc.

Emotion-affected decision making in human simulation.

PubMed

Zhao, Y; Kang, J; Wright, D K

2006-01-01

Human modelling is an interdisciplinary research field. The topic, emotion-affected decision making, was originally a cognitive psychology issue, but is now recognized as an important research direction for both computer science and biomedical modelling. The main aim of this paper is to attempt to bridge the gap between psychology and bioengineering in emotion-affected decision making. The work is based on Ortony's theory of emotions and bounded rationality theory, and attempts to connect the emotion process with decision making. A computational emotion model is proposed, and the initial framework of this model in virtual human simulation within the platform of Virtools is presented.

Human urine and plasma concentrations of bisphenol A extrapolated from pharmacokinetics established in in vivo experiments with chimeric mice with humanized liver and semi-physiological pharmacokinetic modeling.

PubMed

Miyaguchi, Takamori; Suemizu, Hiroshi; Shimizu, Makiko; Shida, Satomi; Nishiyama, Sayako; Takano, Ryohji; Murayama, Norie; Yamazaki, Hiroshi

2015-06-01

The aim of this study was to extrapolate to humans the pharmacokinetics of estrogen analog bisphenol A determined in chimeric mice transplanted with human hepatocytes. Higher plasma concentrations and urinary excretions of bisphenol A glucuronide (a primary metabolite of bisphenol A) were observed in chimeric mice than in control mice after oral administrations, presumably because of enterohepatic circulation of bisphenol A glucuronide in control mice. Bisphenol A glucuronidation was faster in mouse liver microsomes than in human liver microsomes. These findings suggest a predominantly urinary excretion route of bisphenol A glucuronide in chimeric mice with humanized liver. Reported human plasma and urine data for bisphenol A glucuronide after single oral administration of 0.1mg/kg bisphenol A were reasonably estimated using the current semi-physiological pharmacokinetic model extrapolated from humanized mice data using algometric scaling. The reported geometric mean urinary bisphenol A concentration in the U.S. population of 2.64μg/L underwent reverse dosimetry modeling with the current human semi-physiological pharmacokinetic model. This yielded an estimated exposure of 0.024μg/kg/day, which was less than the daily tolerable intake of bisphenol A (50μg/kg/day), implying little risk to humans. Semi-physiological pharmacokinetic modeling will likely prove useful for determining the species-dependent toxicological risk of bisphenol A. Copyright © 2015 Elsevier Inc. All rights reserved.

Physiological Markers of Motor Inhibition during Human Behavior.

PubMed

Duque, Julie; Greenhouse, Ian; Labruna, Ludovica; Ivry, Richard B

2017-04-01

Transcranial magnetic stimulation (TMS) studies in humans have shown that many behaviors engage processes that suppress excitability within the corticospinal tract. Inhibition of the motor output pathway has been extensively studied in the context of action stopping, where a planned movement needs to be abruptly aborted. Recent TMS work has also revealed markers of motor inhibition during the preparation of movement. Here, we review the evidence for motor inhibition during action stopping and action preparation, focusing on studies that have used TMS to monitor changes in the excitability of the corticospinal pathway. We discuss how these physiological results have motivated theoretical models of how the brain selects actions, regulates movement initiation and execution, and switches from one state to another. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sex Differences in Human Fatigability: Mechanisms and Insight to Physiological Responses

PubMed Central

Hunter, Sandra K.

2014-01-01

Sex-related differences in physiology and anatomy are responsible for profound differences in neuromuscular performance and fatigability between men and women. Women are usually less fatigable than men for similar intensity isometric fatiguing contractions. This sex difference in fatigability, however, is task specific because different neuromuscular sites will be stressed when the requirements of the task are altered, and the stress on these sites can differ for men and women. Task variables that can alter the sex difference in fatigue include the type, intensity and speed of contraction, the muscle group assessed, and the environmental conditions. Physiological mechanisms that are responsible for sex-based differences in fatigability may include activation of the motor neuron pool from cortical and subcortical regions, synaptic inputs to the motor neuron pool via activation of metabolically-sensitive small afferent fibres in the muscle, muscle perfusion, and skeletal muscle metabolism and fibre type properties. Non-physiological factors such as the sex bias of studying more males than females in human and animal experiments can also mask a true understanding of the magnitude and mechanisms of sex-based differences in physiology and fatigability. Despite recent developments, there is a tremendous lack of understanding of sex differences in neuromuscular function and fatigability, the prevailing mechanisms and the functional consequences. This review emphasises the need to understand sex-based differences in fatigability in order to shed light on the benefits and limitations that fatigability can exert for men and women during daily tasks, exercise performance, training and rehabilitation in both health and disease. PMID:24433272

Relationship between human physiological parameters and geomagnetic variations of solar origin

NASA Astrophysics Data System (ADS)

Dimitrova, S.

Results presented concern influence of increased geomagnetic activity on some human physiological parameters. The blood pressure and heart rate of 86 volunteers were measured on working days in autumn 2001 (01/10 09/11) and in spring 2002 (08/04 28/05). These periods were chosen because of maximal expected geomagnetic activity. Altogether 2799 recordings were obtained and analysed. Questionnaire information about subjective psycho-physiological complaints was also gathered. MANOVA was employed to check the significance of the influence of three factors on the physiological parameters under consideration. The factors were the following: (1) planetary geomagnetic activity level estimated by Ap-index and divided into five levels; (2) gender males and females; (3) blood pressure degree persons in the group examined were divided into hypotensive, normotensive and hypertensive. Post hoc analysis was performed to elicit the significance of differences in the factors’ levels. The average arterial blood pressure of the group was found to increase significantly with the increase of geomagnetic activity level. The average increment of systolic and diastolic blood pressure of the group examined reached 9%. This effect was present irrespectively of gender. Results obtained suppose that hypertensive persons have the highest sensitivity and the hypotensive persons have the lowest sensitivity of the arterial blood pressure to increase of geomagnetic activity. The results did not show significant changes in the heart rate. The percentage of the persons who reported subjective psycho-physiological complaints was also found to increase significantly with the geomagnetic activity increase and the highest sensitivity was revealed for the hypertensive females.

Altered serotonin physiology in human breast cancers favors paradoxical growth and cell survival

PubMed Central

2009-01-01

Introduction The breast microenvironment can either retard or accelerate the events associated with progression of latent cancers. However, the actions of local physiological mediators in the context of breast cancers are poorly understood. Serotonin (5-HT) is a critical local regulator of epithelial homeostasis in the breast and other organs. Herein, we report complex alterations in the intrinsic mammary gland serotonin system of human breast cancers. Methods Serotonin biosynthetic capacity was analyzed in human breast tumor tissue microarrays using immunohistochemistry for tryptophan hydroxylase 1 (TPH1). Serotonin receptors (5-HT1-7) were analyzed in human breast tumors using the Oncomine database. Serotonin receptor expression, signal transduction, and 5-HT effects on breast cancer cell phenotype were compared in non-transformed and transformed human breast cells. Results In the context of the normal mammary gland, 5-HT acts as a physiological regulator of lactation and involution, in part by favoring growth arrest and cell death. This tightly regulated 5-HT system is subverted in multiple ways in human breast cancers. Specifically, TPH1 expression undergoes a non-linear change during progression, with increased expression during malignant progression. Correspondingly, the tightly regulated pattern of 5-HT receptors becomes dysregulated in human breast cancer cells, resulting in both ectopic expression of some isoforms and suppression of others. The receptor expression change is accompanied by altered downstream signaling of 5-HT receptors in human breast cancer cells, resulting in resistance to 5-HT-induced apoptosis, and stimulated proliferation. Conclusions Our data constitutes the first report of direct involvement of 5-HT in human breast cancer. Increased 5-HT biosynthetic capacity accompanied by multiple changes in 5-HT receptor expression and signaling favor malignant progression of human breast cancer cells (for example, stimulated proliferation

Altered serotonin physiology in human breast cancers favors paradoxical growth and cell survival.

PubMed

Pai, Vaibhav P; Marshall, Aaron M; Hernandez, Laura L; Buckley, Arthur R; Horseman, Nelson D

2009-01-01

The breast microenvironment can either retard or accelerate the events associated with progression of latent cancers. However, the actions of local physiological mediators in the context of breast cancers are poorly understood. Serotonin (5-HT) is a critical local regulator of epithelial homeostasis in the breast and other organs. Herein, we report complex alterations in the intrinsic mammary gland serotonin system of human breast cancers. Serotonin biosynthetic capacity was analyzed in human breast tumor tissue microarrays using immunohistochemistry for tryptophan hydroxylase 1 (TPH1). Serotonin receptors (5-HT1-7) were analyzed in human breast tumors using the Oncomine database. Serotonin receptor expression, signal transduction, and 5-HT effects on breast cancer cell phenotype were compared in non-transformed and transformed human breast cells. In the context of the normal mammary gland, 5-HT acts as a physiological regulator of lactation and involution, in part by favoring growth arrest and cell death. This tightly regulated 5-HT system is subverted in multiple ways in human breast cancers. Specifically, TPH1 expression undergoes a non-linear change during progression, with increased expression during malignant progression. Correspondingly, the tightly regulated pattern of 5-HT receptors becomes dysregulated in human breast cancer cells, resulting in both ectopic expression of some isoforms and suppression of others. The receptor expression change is accompanied by altered downstream signaling of 5-HT receptors in human breast cancer cells, resulting in resistance to 5-HT-induced apoptosis, and stimulated proliferation. Our data constitutes the first report of direct involvement of 5-HT in human breast cancer. Increased 5-HT biosynthetic capacity accompanied by multiple changes in 5-HT receptor expression and signaling favor malignant progression of human breast cancer cells (for example, stimulated proliferation, inappropriate cell survival). This occurs

Physiologically relevant organs on chips.

PubMed

Yum, Kyungsuk; Hong, Soon Gweon; Healy, Kevin E; Lee, Luke P

2014-01-01

Recent advances in integrating microengineering and tissue engineering have generated promising microengineered physiological models for experimental medicine and pharmaceutical research. Here we review the recent development of microengineered physiological systems, or also known as "ogans-on-chips", that reconstitute the physiologically critical features of specific human tissues and organs and their interactions. This technology uses microengineering approaches to construct organ-specific microenvironments, reconstituting tissue structures, tissue-tissue interactions and interfaces, and dynamic mechanical and biochemical stimuli found in specific organs, to direct cells to assemble into functional tissues. We first discuss microengineering approaches to reproduce the key elements of physiologically important, dynamic mechanical microenvironments, biochemical microenvironments, and microarchitectures of specific tissues and organs in microfluidic cell culture systems. This is followed by examples of microengineered individual organ models that incorporate the key elements of physiological microenvironments into single microfluidic cell culture systems to reproduce organ-level functions. Finally, microengineered multiple organ systems that simulate multiple organ interactions to better represent human physiology, including human responses to drugs, is covered in this review. This emerging organs-on-chips technology has the potential to become an alternative to 2D and 3D cell culture and animal models for experimental medicine, human disease modeling, drug development, and toxicology. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Smart sensors and virtual physiology human approach as a basis of personalized therapies in diabetes mellitus.

PubMed

Fernández Peruchena, Carlos M; Prado-Velasco, Manuel

2010-01-01

Diabetes mellitus (DM) has a growing incidence and prevalence in modern societies, pushed by the aging and change of life styles. Despite the huge resources dedicated to improve their quality of life, mortality and morbidity rates, these are still very poor. In this work, DM pathology is revised from clinical and metabolic points of view, as well as mathematical models related to DM, with the aim of justifying an evolution of DM therapies towards the correction of the physiological metabolic loops involved. We analyze the reliability of mathematical models, under the perspective of virtual physiological human (VPH) initiatives, for generating and integrating customized knowledge about patients, which is needed for that evolution. Wearable smart sensors play a key role in this frame, as they provide patient's information to the models.A telehealthcare computational architecture based on distributed smart sensors (first processing layer) and personalized physiological mathematical models integrated in Human Physiological Images (HPI) computational components (second processing layer), is presented. This technology was designed for a renal disease telehealthcare in earlier works and promotes crossroads between smart sensors and the VPH initiative. We suggest that it is able to support a truly personalized, preventive, and predictive healthcare model for the delivery of evolved DM therapies.

Smart Sensors and Virtual Physiology Human Approach as a Basis of Personalized Therapies in Diabetes Mellitus

PubMed Central

Fernández Peruchena, Carlos M; Prado-Velasco, Manuel

2010-01-01

Diabetes mellitus (DM) has a growing incidence and prevalence in modern societies, pushed by the aging and change of life styles. Despite the huge resources dedicated to improve their quality of life, mortality and morbidity rates, these are still very poor. In this work, DM pathology is revised from clinical and metabolic points of view, as well as mathematical models related to DM, with the aim of justifying an evolution of DM therapies towards the correction of the physiological metabolic loops involved. We analyze the reliability of mathematical models, under the perspective of virtual physiological human (VPH) initiatives, for generating and integrating customized knowledge about patients, which is needed for that evolution. Wearable smart sensors play a key role in this frame, as they provide patient’s information to the models. A telehealthcare computational architecture based on distributed smart sensors (first processing layer) and personalized physiological mathematical models integrated in Human Physiological Images (HPI) computational components (second processing layer), is presented. This technology was designed for a renal disease telehealthcare in earlier works and promotes crossroads between smart sensors and the VPH initiative. We suggest that it is able to support a truly personalized, preventive, and predictive healthcare model for the delivery of evolved DM therapies. PMID:21625646

Cigarette smoke differentially affects IL-13-induced gene expression in human airway epithelial cells.

PubMed

Mertens, Tinne C J; van der Does, Anne M; Kistemaker, Loes E; Ninaber, Dennis K; Taube, Christian; Hiemstra, Pieter S

2017-07-01

Allergic airways inflammation in asthma is characterized by an airway epithelial gene signature composed of POSTN , CLCA1 , and SERPINB2 This Th2 gene signature is proposed as a tool to classify patients with asthma into Th2-high and Th2-low phenotypes. However, many asthmatics smoke and the effects of cigarette smoke exposure on the epithelial Th2 gene signature are largely unknown. Therefore, we investigated the combined effect of IL-13 and whole cigarette smoke (CS) on the Th2 gene signature and the mucin-related genes MUC5AC and SPDEF in air-liquid interface differentiated human bronchial (ALI-PBEC) and tracheal epithelial cells (ALI-PTEC). Cultures were exposed to IL-13 for 14 days followed by 5 days of IL-13 with CS exposure. Alternatively, cultures were exposed once daily to CS for 14 days, followed by 5 days CS with IL-13. POSTN , SERPINB2 , and CLCA1 expression were measured 24 h after the last exposure to CS and IL-13. In both models POSTN , SERPINB2 , and CLCA1 expression were increased by IL-13. CS markedly affected the IL-13-induced Th2 gene signature as indicated by a reduced POSTN , CLCA1 , and MUC5AC expression in both models. In contrast, IL-13-induced SERPINB2 expression remained unaffected by CS, whereas SPDEF expression was additively increased. Importantly, cessation of CS exposure failed to restore IL-13-induced POSTN and CLCA1 expression. We show for the first time that CS differentially affects the IL-13-induced gene signature for Th2-high asthma. These findings provide novel insights into the interaction between Th2 inflammation and cigarette smoke that is important for asthma pathogenesis and biomarker-guided therapy in asthma. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

The physiology and biomechanics of competitive swimming.

PubMed

Troup, J P

1999-04-01

Fast swimming, either in the pool, in open water swimming, or in water polo and synchronized swimming, requires maximizing the efficiencies with which the human body can move through a liquid medium. A multitude of factors can affect the ability to swim fast as well as the final outcome. Physiology and biomechanics are the present tools used by sports scientists to determine which factors are important to fast swimming and, subsequently, to determine how the swimmer may maximize these factors to improve performance.

On the Physiological Modulation and Potential Mechanisms Underlying Parieto-Occipital Alpha Oscillations

PubMed Central

Lozano-Soldevilla, Diego

2018-01-01

The parieto-occipital alpha (8–13 Hz) rhythm is by far the strongest spectral fingerprint in the human brain. Almost 90 years later, its physiological origin is still far from clear. In this Research Topic I review human pharmacological studies using electroencephalography (EEG) and magnetoencephalography (MEG) that investigated the physiological mechanisms behind posterior alpha. Based on results from classical and recent experimental studies, I find a wide spectrum of drugs that modulate parieto-occipital alpha power. Alpha frequency is rarely affected, but this might be due to the range of drug dosages employed. Animal and human pharmacological findings suggest that both GABA enhancers and NMDA blockers systematically decrease posterior alpha power. Surprisingly, most of the theoretical frameworks do not seem to embrace these empirical findings and the debate on the functional role of alpha oscillations has been polarized between the inhibition vs. active poles hypotheses. Here, I speculate that the functional role of alpha might depend on physiological excitation as much as on physiological inhibition. This is supported by animal and human pharmacological work showing that GABAergic, glutamatergic, cholinergic, and serotonergic receptors in the thalamus and the cortex play a key role in the regulation of alpha power and frequency. This myriad of physiological modulations fit with the view that the alpha rhythm is a complex rhythm with multiple sources supported by both thalamo-cortical and cortico-cortical loops. Finally, I briefly discuss how future research combining experimental measurements derived from theoretical predictions based of biophysically realistic computational models will be crucial to the reconciliation of these disparate findings. PMID:29670518

Sensing human physiological response using wearable carbon nanotube-based fabrics

NASA Astrophysics Data System (ADS)

Wang, Long; Loh, Kenneth J.; Koo, Helen S.

2016-04-01

Flexible and wearable sensors for human monitoring have received increased attention. Besides detecting motion and physical activity, measuring human vital signals (e.g., respiration rate and body temperature) provide rich data for assessing subjects' physiological or psychological condition. Instead of using conventional, bulky, sensing transducers, the objective of this study was to design and test a wearable, fabric-like sensing system. In particular, multi-walled carbon nanotube (MWCNT)-latex thin films of different MWCNT concentrations were first fabricated using spray coating. Freestanding MWCNT-latex films were then sandwiched between two layers of flexible fabric using iron-on adhesive to form the wearable sensor. Second, to characterize its strain sensing properties, the fabric sensors were subjected to uniaxial and cyclic tensile load tests, and they exhibited relatively stable electromechanical responses. Finally, the wearable sensors were placed on a human subject for monitoring simple motions and for validating their practical strain sensing performance. Overall, the wearable fabric sensor design exhibited advances such as flexibility, ease of fabrication, light weight, low cost, noninvasiveness, and user comfort.

Long-Term Effects of Environmental Endocrine Disruptors on Reproductive Physiology and Behavior

PubMed Central

Patisaul, Heather B.; Adewale, Heather B.

2009-01-01

It is well established that, over the course of development, hormones shape the vertebrate brain such that sex specific physiology and behaviors emerge. Much of this occurs in discrete developmental windows that span gestation through the prenatal period, although it is now becoming clear that at least some of this process continues through puberty. Perturbation of this developmental progression can permanently alter the capacity for reproductive success. Wildlife studies have revealed that exposure to endocrine disrupting compounds (EDCs), either naturally occurring or man made, can profoundly alter reproductive physiology and ultimately impact entire populations. Laboratory studies in rodents and other species have elucidated some of the mechanisms by which this occurs and strongly indicate that humans are also vulnerable to disruption. Use of hormonally active compounds in human medicine has also unfortunately revealed that the developing fetus can be exposed to and affected by endocrine disruptors, and that it might take decades for adverse effects to manifest. Research within the field of environmental endocrine disruption has also contributed to the general understanding of how early life experiences can alter reproductive physiology and behavior through non-genomic, epigenetic mechanisms such as DNA methylation and histone acetylation. These types of effects have the potential to impact future generations if the germ line is affected. This review provides an overview of how exposure to EDCs, particularly those that interfere with estrogen action, impacts reproductive physiology and behaviors in vertebrates. PMID:19587848

Human physiological models of insomnia.

PubMed

Richardson, Gary S

2007-12-01

Despite the wide prevalence and important consequences of insomnia, remarkably little is known about its pathophysiology. Available models exist primarily in the psychological domain and derive from the demonstrated efficacy of behavioral treatment approaches to insomnia management. However, these models offer little specific prediction about the anatomic or physiological foundation of chronic primary insomnia. On the other hand, a growing body of data on the physiology of sleep supports a reasonably circumscribed overview of possible pathophysiological mechanisms, as well as the development of physiological models of insomnia to guide future research. As a pragmatic step, these models focus on primary insomnia, as opposed to comorbid insomnias, because the latter is by its nature a much more heterogeneous presentation, reflecting the effects of the distinct comorbid condition. Current understanding of the regulation of sleep and wakefulness in mammalian brain supports four broad candidate areas: 1) disruption of the sleep homeostat; 2) disruption of the circadian clock; 3) disruption of intrinsic systems responsible for the expression of sleep states; or 4) disruption (hyperactivity) of extrinsic systems capable of over-riding normal sleep-wake regulation. This review examines each of the four candidate pathophysiological mechanisms and the available data in support of each. While studies that directly test the viability of each model are not yet available, descriptive data on primary insomnia favor the involvement of dysfunctional extrinsic stress-response systems in the pathology of primary chronic insomnia.

Patterning of physiological and affective responses in older active adults during a maximal graded exercise test and self-selected exercise.

PubMed

Smith, Ashleigh E; Eston, Roger; Tempest, Gavin D; Norton, Belinda; Parfitt, Gaynor

2015-09-01

The American College of Sports Medicine has highlighted the importance of considering the physiological and affective responses to exercise when setting exercise intensity. Here, we examined the relationship between exercise intensity and physiological and affective responses in active older adults. Eighteen participants (60-74 years; 64.4 ± 3.9; 8 women) completed a maximal graded exercise test (GXT) on a treadmill. Since time to exhaustion in the GXT differed between participants, heart rate (HR), oxygen consumption (VO2), affective valence (affect) and rating of perceived exertion (RPE) were expressed relative to the individually determined ventilatory threshold (%atVT). During the GXT, VO2, HR and RPE increased linearly (all P < 0.01). Affect declined initially (but remained positive) (P = 0.03), stabilised around VT (still positive) (P > 0.05) and became negative towards the end of the test (P < 0.01). In a subsequent session, participants completed a 20-min bout of self-selected exercise (at a preferred intensity). Initially, participants chose to exercise below VT (88.2 ± 17.4 %VO2atVT); however, the intensity was adjusted to work at, or above VT (107.7 ± 19.9 %VO2atVT) after 10 min (P < 0.001), whilst affect remained positive. Together, these findings indicate that exercise around VT, whether administered during an exercise test, or self-selected by the participant, is likely to result in positive affective responses in older adults.

Human Physiology in an Aquatic Environment.

PubMed

Pendergast, David R; Moon, Richard E; Krasney, John J; Held, Heather E; Zamparo, Paola

2015-09-20

Water covers over 70% of the earth, has varying depths and temperatures and contains much of the earth's resources. Head-out water immersion (HOWI) or submersion at various depths (diving) in water of thermoneutral (TN) temperature elicits profound cardiorespiratory, endocrine, and renal responses. The translocation of blood into the thorax and elevation of plasma volume by autotransfusion of fluid from cells to the vascular compartment lead to increased cardiac stroke volume and output and there is a hyperperfusion of some tissues. Pulmonary artery and capillary hydrostatic pressures increase causing a decline in vital capacity with the potential for pulmonary edema. Atrial stretch and increased arterial pressure cause reflex autonomic responses which result in endocrine changes that return plasma volume and arterial pressure to preimmersion levels. Plasma volume is regulated via a reflex diuresis and natriuresis. Hydrostatic pressure also leads to elastic loading of the chest, increasing work of breathing, energy cost, and thus blood flow to respiratory muscles. Decreases in water temperature in HOWI do not affect the cardiac output compared to TN; however, they influence heart rate and the distribution of muscle and fat blood flow. The reduced muscle blood flow results in a reduced maximal oxygen consumption. The properties of water determine the mechanical load and the physiological responses during exercise in water (e.g. swimming and water based activities). Increased hydrostatic pressure caused by submersion does not affect stroke volume; however, progressive bradycardia decreases cardiac output. During submersion, compressed gas must be breathed which introduces the potential for oxygen toxicity, narcosis due to nitrogen, and tissue and vascular gas bubbles during decompression and after may cause pain in joints and the nervous system. Copyright © 2015 John Wiley & Sons, Inc.

Effects of hydroxocobalamin on carboxyhemoglobin measured under physiologic and pathologic conditions.

PubMed

Pace, R; Bon Homme, M; Hoffman, R S; Lugassy, D

2014-08-01

Pre-hospital administration of hydroxocobalamin (B12a) is used for empiric treatment of cyanide poisoning because cyanide poisoning is difficult to identify and requires immediate treatment. B12a interferes with the accuracy of several blood laboratory tests. This study aimed to explore how B12a affects carboxyhemoglobin (COHb) measurements in human blood at both physiologic and pathologic COHb levels. Several clinically relevant concentrations of B12a were added to human blood samples containing physiologic (∼ 3%) and pathologic (30% and 50%) COHb levels. We then measured the COHb levels of the samples using two different co-oximeters, the Radiometer ABL 700 and the Rapidpoint 500, and compared to their actual baseline COHb levels. B12a had minimal effects on the COHb measured at both physiologic and pathologic levels when measured on the Radiometer. In contrast, the Rapidpoint B12a caused a dose-dependent decrease in the COHb measured, especially of pathologic COHb levels (∼ 30 and 50%). The magnitude of B12a interference on measured COHb is dependent upon the specific co-oximeter used, the actual COHb level and the serum B12a concentration. These errors may potentially influence clinical decision making and thus affect patient outcomes. Our findings emphasize the importance of measuring COHb levels on blood samples collected prior to B12a administration.

Default, Cognitive, and Affective Brain Networks in Human Tinnitus

DTIC Science & Technology

2015-10-01

AWARD NUMBER: W81XWH-13-1-0491 TITLE: Default, Cognitive, and Affective Brain Networks in Human Tinnitus PRINCIPAL INVESTIGATOR: Jennifer R...SUBTITLE 5a. CONTRACT NUMBER Default, Cognitive and Affective Brain Networks in Human Tinnitus 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Tinnitus is a major health problem among those currently and formerly in military

The EuroPhysiome, STEP and a roadmap for the virtual physiological human.

PubMed

Fenner, J W; Brook, B; Clapworthy, G; Coveney, P V; Feipel, V; Gregersen, H; Hose, D R; Kohl, P; Lawford, P; McCormack, K M; Pinney, D; Thomas, S R; Van Sint Jan, S; Waters, S; Viceconti, M

2008-09-13

Biomedical science and its allied disciplines are entering a new era in which computational methods and technologies are poised to play a prevalent role in supporting collaborative investigation of the human body. Within Europe, this has its focus in the virtual physiological human (VPH), which is an evolving entity that has emerged from the EuroPhysiome initiative and the strategy for the EuroPhysiome (STEP) consortium. The VPH is intended to be a solution to common infrastructure needs for physiome projects across the globe, providing a unifying architecture that facilitates integration and prediction, ultimately creating a framework capable of describing Homo sapiens in silico. The routine reliance of the biomedical industry, biomedical research and clinical practice on information technology (IT) highlights the importance of a tailor-made and robust IT infrastructure, but numerous challenges need to be addressed if the VPH is to become a mature technological reality. Appropriate investment will reap considerable rewards, since it is anticipated that the VPH will influence all sectors of society, with implications predominantly for improved healthcare, improved competitiveness in industry and greater understanding of (patho)physiological processes. This paper considers issues pertinent to the development of the VPH, highlighted by the work of the STEP consortium.

Human age and skin physiology shape diversity and abundance of Archaea on skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moissl-Eichinger, Christine; Probst, Alexander J.; Birarda, Giovanni

The human skin microbiome acts as an important barrier protecting our body from pathogens and other environmental influences. Recent investigations have provided evidence that Archaea are a constant but highly variable component of the human skin microbiome, yet factors that determine their abundance changes are unknown. Here, we tested the hypothesis that the abundance of archaea on human skin is influenced by human age and skin physiology by quantitative PCR of 51 different skin samples taken from human subjects of various age. Our results reveal that archaea are more abundant in human subjects either older than 60 years or youngermore » than 12 years as compared to middle-aged human subjects. These results, together with results obtained from spectroscopy analysis, allowed us gain first insights into a potential link of lower sebum levels and lipid content and thus reduced skin moisture with an increase in archaeal signatures. In conclusion, amplicon sequencing of selected samples revealed the prevalence of specific eury- and mainly thaumarchaeal taxa, represented by a core archaeome of the human skin.« less

Human age and skin physiology shape diversity and abundance of Archaea on skin

DOE PAGES

Moissl-Eichinger, Christine; Probst, Alexander J.; Birarda, Giovanni; ...

2017-06-22

The human skin microbiome acts as an important barrier protecting our body from pathogens and other environmental influences. Recent investigations have provided evidence that Archaea are a constant but highly variable component of the human skin microbiome, yet factors that determine their abundance changes are unknown. Here, we tested the hypothesis that the abundance of archaea on human skin is influenced by human age and skin physiology by quantitative PCR of 51 different skin samples taken from human subjects of various age. Our results reveal that archaea are more abundant in human subjects either older than 60 years or youngermore » than 12 years as compared to middle-aged human subjects. These results, together with results obtained from spectroscopy analysis, allowed us gain first insights into a potential link of lower sebum levels and lipid content and thus reduced skin moisture with an increase in archaeal signatures. In conclusion, amplicon sequencing of selected samples revealed the prevalence of specific eury- and mainly thaumarchaeal taxa, represented by a core archaeome of the human skin.« less

Nutritional physiology and ecology of wildlife in a changing world

PubMed Central

Peiman, Kathryn S.; Raubenheimer, David; Cooke, Steven J.

2017-01-01

Abstract Over the last century, humans have modified landscapes, generated pollution and provided opportunities for exotic species to invade areas where they did not evolve. In addition, humans now interact with animals in a growing number of ways (e.g. ecotourism). As a result, the quality (i.e. nutrient composition) and quantity (i.e. food abundance) of dietary items consumed by wildlife have, in many cases, changed. We present representative examples of the extent to which vertebrate foraging behaviour, food availability (quantity and quality) and digestive physiology have been modified due to human-induced environmental changes and human activities. We find that these effects can be quite extensive, especially as a result of pollution and human-provisioned food sources (despite good intentions). We also discuss the role of nutrition in conservation practices, from the perspective of both in situ and ex situ conservation. Though we find that the changes in the nutritional ecology and physiology of wildlife due to human alterations are typically negative and largely involve impacts on foraging behaviour and food availability, the extent to which these will affect the fitness of organisms and result in evolutionary changes is not clearly understood, and requires further investigation. PMID:28740638

Physiological Motion Axis for the Seat of a Dynamic Office Chair.

PubMed

Kuster, Roman Peter; Bauer, Christoph Markus; Oetiker, Sarah; Kool, Jan

2016-09-01

The aim of this study was to determine and verify the optimal location of the motion axis (MA) for the seat of a dynamic office chair. A dynamic seat that supports pelvic motion may improve physical well-being and decrease the risk of sitting-associated disorders. However, office work requires an undisturbed view on the work task, which means a stable position of the upper trunk and head. Current dynamic office chairs do not fulfill this need. Consequently, a dynamic seat was adapted to the physiological kinematics of the human spine. Three-dimensional motion tracking in free sitting helped determine the physiological MA of the spine in the frontal plane. Three dynamic seats with physiological, lower, and higher MA were compared in stable upper body posture (thorax inclination) and seat support of pelvic motion (dynamic fitting accuracy). Spinal kinematics during sitting and walking were compared. The physiological MA was at the level of the 11th thoracic vertebra, causing minimal thorax inclination and high dynamic fitting accuracy. Spinal motion in active sitting and walking was similar. The physiological MA of the seat allows considerable lateral flexion of the spine similar to walking with a stable upper body posture and a high seat support of pelvic motion. The physiological MA enables lateral flexion of the spine, similar to walking, without affecting stable upper body posture, thus allowing active sitting while focusing on work. © 2016, Human Factors and Ergonomics Society.

Physiological Information Database (PID)

EPA Science Inventory

EPA has developed a physiological information database (created using Microsoft ACCESS) intended to be used in PBPK modeling. The database contains physiological parameter values for humans from early childhood through senescence as well as similar data for laboratory animal spec...

Genetic alterations affecting cholesterol metabolism and human fertility.

PubMed

DeAngelis, Anthony M; Roy-O'Reilly, Meaghan; Rodriguez, Annabelle

2014-11-01

Single nucleotide polymorphisms (SNPs) represent genetic variations among individuals in a population. In medicine, these small variations in the DNA sequence may significantly impact an individual's response to certain drugs or influence the risk of developing certain diseases. In the field of reproductive medicine, a significant amount of research has been devoted to identifying polymorphisms which may impact steroidogenesis and fertility. This review discusses current understanding of the effects of genetic variations in cholesterol metabolic pathways on human fertility that bridge novel linkages between cholesterol metabolism and reproductive health. For example, the role of the low-density lipoprotein receptor (LDLR) in cellular metabolism and human reproduction has been well studied, whereas there is now an emerging body of research on the role of the high-density lipoprotein (HDL) receptor scavenger receptor class B type I (SR-BI) in human lipid metabolism and female reproduction. Identifying and understanding how polymorphisms in the SCARB1 gene or other genes related to lipid metabolism impact human physiology is essential and will play a major role in the development of personalized medicine for improved diagnosis and treatment of infertility. © 2014 by the Society for the Study of Reproduction, Inc.

The power of clinicians' affective communication: how reassurance about non-abandonment can reduce patients' physiological arousal and increase information recall in bad news consultations. An experimental study using analogue patients.

PubMed

Sep, Milou S C; van Osch, Mara; van Vliet, Liesbeth M; Smets, Ellen M A; Bensing, Jozien M

2014-04-01

The diagnosis of incurable cancer may evoke physiological arousal in patients. Physiological arousal can negatively impact patients' recall of information provided in the medical consultation. We aim to investigate whether clinicians' affective communication during a bad news consultation will decrease patients' physiological arousal and will improve recall. Healthy women (N=50), acting as analogue patients, were randomly assigned to watch one out of the two versions of a scripted video-vignette of a bad news consultation in which clinician's communication differed: standard vs. affective communication. Participants' skin conductance levels were obtained during video-watching, and afterwards their recall was assessed. While the diagnosis increased skin conductance levels in all analogue patients, skin conductance levels during the remainder of the consultation decreased more in the affective communication condition than in the standard condition. Analogue patients' recall was significantly higher in the affective condition. Breaking bad news evokes physiological arousal. Affective communication can decrease this evoked physiological arousal and might be partly responsible for analogue patients' enhanced information recall. Although our findings need to be translated to clinical patients, they suggest that clinicians need to deal with patients' emotions before providing additional medical information. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Physiological responses to prolonged bed rest in humans: A compendium of research, 1981-1988

NASA Technical Reports Server (NTRS)

Luu, Phuong B.; Ortiz, Vanessa; Barnes, Paul R.; Greenleaf, John E.

1990-01-01

Clinical observations and results form more basic studies that help to elucidate the physiological mechanisms of the adaptation of humans to prolonged bed rest. If the authors' abstract or summary was appropriate, it was included. In some cases a more detailed synopsis was provided under the subheadings of purpose, methods, results, and conclusions.

Central respiratory chemosensitivity and cerebrovascular CO2 reactivity: a rebreathing demonstration illustrating integrative human physiology.

PubMed

MacKay, Christina M; Skow, Rachel J; Tymko, Michael M; Boulet, Lindsey M; Davenport, Margie H; Steinback, Craig D; Ainslie, Philip N; Lemieux, Chantelle C M; Day, Trevor A

2016-03-01

One of the most effective ways of engaging students of physiology and medicine is through laboratory demonstrations and case studies that combine 1) the use of equipment, 2) problem solving, 3) visual representations, and 4) manipulation and interpretation of data. Depending on the measurements made and the type of test, laboratory demonstrations have the added benefit of being able to show multiple organ system integration. Many research techniques can also serve as effective demonstrations of integrative human physiology. The "Duffin" hyperoxic rebreathing test is often used in research settings as a test of central respiratory chemosensitivity and cerebrovascular reactivity to CO2. We aimed to demonstrate the utility of the hyperoxic rebreathing test for both respiratory and cerebrovascular responses to increases in CO2 and illustrate the integration of the respiratory and cerebrovascular systems. In the present article, methods such as spirometry, respiratory gas analysis, and transcranial Doppler ultrasound are described, and raw data traces can be adopted for discussion in a tutorial setting. If educators have these instruments available, instructions on how to carry out the test are provided so students can collect their own data. In either case, data analysis and quantification are discussed, including principles of linear regression, calculation of slope, the coefficient of determination (R(2)), and differences between plotting absolute versus normalized data. Using the hyperoxic rebreathing test as a demonstration of the complex interaction and integration between the respiratory and cerebrovascular systems provides senior undergraduate, graduate, and medical students with an advanced understanding of the integrative nature of human physiology. Copyright © 2016 The American Physiological Society.

Physiological and Biomechanical Considerations for a Human Mars Mission

NASA Astrophysics Data System (ADS)

Hawkey, A.

Evolving on Earth has made humans perfectly adapted, both physiologically and biomechanically, to its gravity and atmospheric conditions. Leaving the Earth and its protective environment, therefore, results in the degradation of a number of human systems. Long-duration stays on the International Space Station (ISS) are accompanied by significant effects on crew's cardiovascular, vestibular and musculoskeletal systems. Bone loss and muscle atrophy are experienced at a rate of 1-3% and 5% per month respectively, while VO2 (oxygen consumption) measurements are reduced by approximately 25% after a few weeks in space. If these figures are simply extrapolated, a future human mission to Mars will be seriously jeopardised and crews may find they cross the threshold of bone and muscle loss and aerobic fitness - ultimately with them being unable to return to Earth. When arriving on Mars, considerable biomechanical alterations will also occur. Optimum walking speeds will be approximately 30% lower and transitioning from a walk to a run will occur at a speed 25% slower. Peak vertical forces will be reduced by as much as 50%, while stride length, stride time and airborne time will all increase. On Mars, half as much energy will be required to travel the equivalent distance on Earth and it will be 65% more economical to run rather than to walk.

Possible psycho-physiological consequences of human long-term space missions

NASA Astrophysics Data System (ADS)

Belisheva, N. K.; Lammer, H.; Biernat, H. K.; Kachanova, T. L.; Kalashnikova, I. V.

Experiments carried out on the Earth s surface during different years and under contrast periods of solar activity have shown that the functional state of biosystems including the human organisms are controlled by global and local geocosmical agents Our finding have a close relation to space research because they demonstrate the reactions of biosystems on variations of global and local geocosmical agents and the mechanisms of modulations of biosystems state by geocosmical agents We revealed the role of variations of the geomagnetic field for the stimulation of immune systems functional state of peripheral blood human brain growth of microflora skin covers and pathogenic microorganisms The study of the psycho-physiological state of the human organism has demonstrated that an increase of the neutron intensity near the Earth s surface is associated with anxiety decrease of normal and increase of paradox reactions of examinees The analysis of the human brain functional state in dependent on the geomagnetic variation structure dose under exposure to the variations of geomagnetic field in a certain amplitude-frequency range and also the intensity of the nucleon component of secondary cosmic rays showed that the stable and unstable states of the human brain are determined by geomagnetic field variations and the intensity of the nucleon component The stable state of the brain manifested under the periodic oscillations of the geomagnetic field in a certain amplitude-frequency range The low level of geomagnetic activity associated with an

Human Cognitive Limitations. Broad, Consistent, Clinical Application of Physiological Principles Will Require Decision Support.

PubMed

Morris, Alan H

2018-02-01

Our education system seems to fail to enable clinicians to broadly understand core physiological principles. The emphasis on reductionist science, including "omics" branches of research, has likely contributed to this decrease in understanding. Consequently, clinicians cannot be expected to consistently make clinical decisions linked to best physiological evidence. This is a large-scale problem with multiple determinants, within an even larger clinical decision problem: the failure of clinicians to consistently link their decisions to best evidence. Clinicians, like all human decision-makers, suffer from significant cognitive limitations. Detailed context-sensitive computer protocols can generate personalized medicine instructions that are well matched to individual patient needs over time and can partially resolve this problem.

Sensitivity analysis of physiological factors in space habitat design

NASA Technical Reports Server (NTRS)

Billingham, J.

1982-01-01

The costs incurred by design conservatism in space habitat design are discussed from a structural standpoint, and areas of physiological research into less than earth-normal conditions that offer the greatest potential decrease in habitat construction and operating costs are studied. The established range of human tolerance limits is defined for those physiological conditions which directly affect habitat structural design. These entire ranges or portions thereof are set as habitat design constraints as a function of habitat population and degree of ecological closure. Calculations are performed to determine the structural weight and cost associated with each discrete population size and its selected environmental conditions, on the basis of habitable volume equivalence for four basic habitat configurations: sphere, cylinder with hemispherical ends, torus, and crystal palace.

A Study of the Physiological Factors Affecting the Nature of the Adult Learner in the Phoenix Air National Guard.

ERIC Educational Resources Information Center

Torbert, James Brison

An investigation reviewed current literature in the field of physiological factors affecting the adult learning environment. These findings were compared to the academic learning environment at the Phoenix Air National Guard. The end product was a set of recommendations for management to implement in order to improve the learning climate for the…

The vaginal microbiota, host defence and reproductive physiology

PubMed Central

Smith, Steven B

2016-01-01

Abstract The interaction between the human host and the vaginal microbiota is highly dynamic. Major changes in the vaginal physiology and microbiota over a woman's lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy, while daily fluctuations in microbial composition observed through culture‐independent studies are more likely to be the results of daily life activities and behaviours. The vaginal microbiota of reproductive‐aged women is largely made up of at least five different community state types. Four of these community state types are dominated by lactic‐acid producing Lactobacillus spp. while the fifth is commonly composed of anaerobes and strict anaerobes and is sometimes associated with vaginal symptoms. The production of lactic acid has been associated with contributing to the overall health of the vagina due to its direct and indirect effects on pathogens and host defence. Some species associated with non‐Lactobacillus vaginal microbiota may trigger immune responses as well as degrade the host mucosa, processes that ultimately increase susceptibility to infections and contribute to negative reproductive outcomes such as infertility and preterm birth. Further studies are needed to better understand the functional underpinnings of how the vaginal microbiota affect host physiology but also how host physiology affects the vaginal microbiota. Understanding this fine‐tuned interaction is key to maintaining women's reproductive health. PMID:27373840

Aging Affects Adaptation to Sound-Level Statistics in Human Auditory Cortex.

PubMed

Herrmann, Björn; Maess, Burkhard; Johnsrude, Ingrid S

2018-02-21

Optimal perception requires efficient and adaptive neural processing of sensory input. Neurons in nonhuman mammals adapt to the statistical properties of acoustic feature distributions such that they become sensitive to sounds that are most likely to occur in the environment. However, whether human auditory responses adapt to stimulus statistical distributions and how aging affects adaptation to stimulus statistics is unknown. We used MEG to study how exposure to different distributions of sound levels affects adaptation in auditory cortex of younger (mean: 25 years; n = 19) and older (mean: 64 years; n = 20) adults (male and female). Participants passively listened to two sound-level distributions with different modes (either 15 or 45 dB sensation level). In a control block with long interstimulus intervals, allowing neural populations to recover from adaptation, neural response magnitudes were similar between younger and older adults. Critically, both age groups demonstrated adaptation to sound-level stimulus statistics, but adaptation was altered for older compared with younger people: in the older group, neural responses continued to be sensitive to sound level under conditions in which responses were fully adapted in the younger group. The lack of full adaptation to the statistics of the sensory environment may be a physiological mechanism underlying the known difficulty that older adults have with filtering out irrelevant sensory information. SIGNIFICANCE STATEMENT Behavior requires efficient processing of acoustic stimulation. Animal work suggests that neurons accomplish efficient processing by adjusting their response sensitivity depending on statistical properties of the acoustic environment. Little is known about the extent to which this adaptation to stimulus statistics generalizes to humans, particularly to older humans. We used MEG to investigate how aging influences adaptation to sound-level statistics. Listeners were presented with sounds drawn from

A human life-stage physiologically based pharmacokinetic and pharmacodynamic model for chlorpyrifos: development and validation.

PubMed

Smith, Jordan Ned; Hinderliter, Paul M; Timchalk, Charles; Bartels, Michael J; Poet, Torka S

2014-08-01

Sensitivity to some chemicals in animals and humans are known to vary with age. Age-related changes in sensitivity to chlorpyrifos have been reported in animal models. A life-stage physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model was developed to predict disposition of chlorpyrifos and its metabolites, chlorpyrifos-oxon (the ultimate toxicant) and 3,5,6-trichloro-2-pyridinol (TCPy), as well as B-esterase inhibition by chlorpyrifos-oxon in humans. In this model, previously measured age-dependent metabolism of chlorpyrifos and chlorpyrifos-oxon were integrated into age-related descriptions of human anatomy and physiology. The life-stage PBPK/PD model was calibrated and tested against controlled adult human exposure studies. Simulations suggest age-dependent pharmacokinetics and response may exist. At oral doses ⩾0.6mg/kg of chlorpyrifos (100- to 1000-fold higher than environmental exposure levels), 6months old children are predicted to have higher levels of chlorpyrifos-oxon in blood and higher levels of red blood cell cholinesterase inhibition compared to adults from equivalent doses. At lower doses more relevant to environmental exposures, simulations predict that adults will have slightly higher levels of chlorpyrifos-oxon in blood and greater cholinesterase inhibition. This model provides a computational framework for age-comparative simulations that can be utilized to predict chlorpyrifos disposition and biological response over various postnatal life stages. Copyright © 2013 Elsevier Inc. All rights reserved.

A preliminary analysis of human factors affecting the recognition accuracy of a discrete word recognizer for C3 systems

NASA Astrophysics Data System (ADS)

Yellen, H. W.

1983-03-01

Literature pertaining to Voice Recognition abounds with information relevant to the assessment of transitory speech recognition devices. In the past, engineering requirements have dictated the path this technology followed. But, other factors do exist that influence recognition accuracy. This thesis explores the impact of Human Factors on the successful recognition of speech, principally addressing the differences or variability among users. A Threshold Technology T-600 was used for a 100 utterance vocubalary to test 44 subjects. A statistical analysis was conducted on 5 generic categories of Human Factors: Occupational, Operational, Psychological, Physiological and Personal. How the equipment is trained and the experience level of the speaker were found to be key characteristics influencing recognition accuracy. To a lesser extent computer experience, time or week, accent, vital capacity and rate of air flow, speaker cooperativeness and anxiety were found to affect overall error rates.

The fire-walker's high: affect and physiological responses in an extreme collective ritual.

PubMed

Fischer, Ronald; Xygalatas, Dimitris; Mitkidis, Panagiotis; Reddish, Paul; Tok, Penny; Konvalinka, Ivana; Bulbulia, Joseph

2014-01-01

How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates) and self-reported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers), low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers) and spectators (unrelated/unknown to the fire-walkers). We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual.

Transcriptomics and proteomics show that selenium affects inflammation, cytoskeleton, and cancer pathways in human rectal biopsies.

PubMed

Méplan, Catherine; Johnson, Ian T; Polley, Abigael C J; Cockell, Simon; Bradburn, David M; Commane, Daniel M; Arasaradnam, Ramesh P; Mulholland, Francis; Zupanic, Anze; Mathers, John C; Hesketh, John

2016-08-01

Epidemiologic studies highlight the potential role of dietary selenium (Se) in colorectal cancer prevention. Our goal was to elucidate whether expression of factors crucial for colorectal homoeostasis is affected by physiologic differences in Se status. Using transcriptomics and proteomics followed by pathway analysis, we identified pathways affected by Se status in rectal biopsies from 22 healthy adults, including 11 controls with optimal status (mean plasma Se = 1.43 μM) and 11 subjects with suboptimal status (mean plasma Se = 0.86 μM). We observed that 254 genes and 26 proteins implicated in cancer (80%), immune function and inflammatory response (40%), cell growth and proliferation (70%), cellular movement, and cell death (50%) were differentially expressed between the 2 groups. Expression of 69 genes, including selenoproteins W1 and K, which are genes involved in cytoskeleton remodelling and transcription factor NFκB signaling, correlated significantly with Se status. Integrating proteomics and transcriptomics datasets revealed reduced inflammatory and immune responses and cytoskeleton remodelling in the suboptimal Se status group. This is the first study combining omics technologies to describe the impact of differences in Se status on colorectal expression patterns, revealing that suboptimal Se status could alter inflammatory signaling and cytoskeleton in human rectal mucosa and so influence cancer risk.-Méplan, C., Johnson, I. T., Polley, A. C. J., Cockell, S., Bradburn, D. M., Commane, D. M., Arasaradnam, R. P., Mulholland, F., Zupanic, A., Mathers, J. C., Hesketh, J. Transcriptomics and proteomics show that selenium affects inflammation, cytoskeleton, and cancer pathways in human rectal biopsies. © The Author(s).

User Interactive Software for Analysis of Human Physiological Data

NASA Technical Reports Server (NTRS)

Cowings, Patricia S.; Toscano, William; Taylor, Bruce C.; Acharya, Soumydipta

2006-01-01

Ambulatory physiological monitoring has been used to study human health and performance in space and in a variety of Earth-based environments (e.g., military aircraft, armored vehicles, small groups in isolation, and patients). Large, multi-channel data files are typically recorded in these environments, and these files often require the removal of contaminated data prior to processing and analyses. Physiological data processing can now be performed with user-friendly, interactive software developed by the Ames Psychophysiology Research Laboratory. This software, which runs on a Windows platform, contains various signal-processing routines for both time- and frequency- domain data analyses (e.g., peak detection, differentiation and integration, digital filtering, adaptive thresholds, Fast Fourier Transform power spectrum, auto-correlation, etc.). Data acquired with any ambulatory monitoring system that provides text or binary file format are easily imported to the processing software. The application provides a graphical user interface where one can manually select and correct data artifacts utilizing linear and zero interpolation and adding trigger points for missed peaks. Block and moving average routines are also provided for data reduction. Processed data in numeric and graphic format can be exported to Excel. This software, PostProc (for post-processing) requires the Dadisp engineering spreadsheet (DSP Development Corp), or equivalent, for implementation. Specific processing routines were written for electrocardiography, electroencephalography, electromyography, blood pressure, skin conductance level, impedance cardiography (cardiac output, stroke volume, thoracic fluid volume), temperature, and respiration

Physiological stress responses in wild Asian elephants Elephas maximus in a human-dominated landscape in the Western Ghats, southern India.

PubMed

Vijayakrishnan, Sreedhar; Kumar, Mavatur Ananda; Umapathy, G; Kumar, Vinod; Sinha, Anindya

2018-05-17

Increasing anthropogenic pressures on forests, especially in the tropical regions of the world, have restricted several large mammalian species such as the Asian elephant to fragmented habitats within human-dominated landscapes. In this study, we assessed the effects of an anthropogenic landscape and its associated conflict with humans on the physiological stress responses displayed by Asian elephants in the Anamalai Hills of the Western Ghats mountains in south India. We have quantified faecal glucocorticoid metabolite (FGM) concentrations in focal individual elephants within and across herds, inhabiting both anthropogenic and natural habitats, and evaluated their physiological responses to different socio-ecological situations between November 2013 and April 2014. Physiological stress responses varied significantly among the tested elephant age- and sex categories but not across different types of social organisation. Adults generally showed higher FGM concentrations, even in the absence of stressors, than did any other age category. Males also appeared to have higher stress responses than did females. Although there was no significant variation in mean stress levels between elephants on the plateau in the absence of human interactions and those in adjacent, relatively undisturbed forest habitats, FGM concentrations increased significantly for adult and subadult individuals as well as for calves following drives, during which elephants were driven off aggressively by people. Our study emphasises the general importance of understanding individual variation in physiology and behaviour within a population of a seriously threatened mammalian species, the Asian elephant, and specifically highlights the need for long-term monitoring of the stress physiology and behavioural responses of individual elephants across both human-dominated and natural landscapes. Such studies would not only provide comprehensive insights into the adaptive biology of elephants in changing

Do therapeutic imagery practices affect physiological and emotional indicators of threat in high self-critics?

PubMed

Duarte, Joana; McEwan, Kirsten; Barnes, Christopher; Gilbert, Paul; Maratos, Frances A

2015-09-01

Imagery is known to be a powerful means of stimulating various physiological processes and is increasingly used within standard psychological therapies. Compassion-focused imagery (CFI) has been used to stimulate affiliative emotion in people with mental health problems. However, evidence suggests that self-critical individuals may have particular difficulties in this domain with single trials. The aim of the present study was to further investigate the role of self-criticism in responsiveness to CFI by specifically pre-selecting participants based on trait self-criticism. Using the Forms of Self-Criticism/Self-Reassuring Scale, 29 individuals from a total sample of 139 were pre-selected to determine how self-criticism impacts upon an initial instance of imagery. All participants took part in three activities: a control imagery intervention (useable data N = 25), a standard CFI intervention (useable data N = 25), and a non-intervention control (useable data N = 24). Physiological measurements (alpha amylase) as well as questionnaire measures of emotional responding (i.e., the Positive and Negative Affect Schedule, the Types of Positive Affect Scale, and the State Adult Attachment Scale) were taken before and after the different interventions. Following both imagery interventions, repeated measures analyses revealed that alpha amylase increased significantly for high self-critics compared with low self-critics. High self-critics (HSC) also reported greater insecurity on entering the imagery session and more negative CFI experiences compared with low self-critics. Data demonstrate that HSC respond negatively to imagery interventions in a single trial. This highlights that imagery focused therapies (e.g., CFI) need interventions that manage fears, blocks, and resistances to the techniques, particularly in HSC. An initial instance of imagery (e.g., CFI) can be frightening for people who have a tendency to be self-critical. This research provides examples of

Physiological and Biomechanical Mechanisms of Distance Specific Human Running Performance.

PubMed

Thompson, M A

2017-08-01

Running events range from 60-m sprints to ultra-marathons covering 100 miles or more, which presents an interesting diversity in terms of the parameters for successful performance. Here, we review the physiological and biomechanical variations underlying elite human running performance in sprint to ultramarathon distances. Maximal running speeds observed in sprint disciplines are achieved by high vertical ground reaction forces applied over short contact times. To create this high force output, sprint events rely heavily on anaerobic metabolism, as well as a high number and large cross-sectional area of type II fibers in the leg muscles. Middle distance running performance is characterized by intermediates of biomechanical and physiological parameters, with the possibility of unique combinations of each leading to high-level performance. The relatively fast velocities in mid-distance events require a high mechanical power output, though ground reaction forces are less than in sprinting. Elite mid-distance runners exhibit local muscle adaptations that, along with a large anaerobic capacity, provide the ability to generate a high power output. Aerobic capacity starts to become an important aspect of performance in middle distance events, especially as distance increases. In distance running events, V˙O2max is an important determinant of performance, but is relatively homogeneous in elite runners. V˙O2 and velocity at lactate threshold have been shown to be superior predictors of elite distance running performance. Ultramarathons are relatively new running events, as such, less is known about physiological and biomechanical parameters that underlie ultra-marathon performance. However, it is clear that performance in these events is related to aerobic capacity, fuel utilization, and fatigue resistance. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology 2017. This work is written by US Government employees and is in

Physical exercise in aging human skeletal muscle increases mitochondrial calcium uniporter expression levels and affects mitochondria dynamics.

PubMed

Zampieri, Sandra; Mammucari, Cristina; Romanello, Vanina; Barberi, Laura; Pietrangelo, Laura; Fusella, Aurora; Mosole, Simone; Gherardi, Gaia; Höfer, Christian; Löfler, Stefan; Sarabon, Nejc; Cvecka, Jan; Krenn, Matthias; Carraro, Ugo; Kern, Helmut; Protasi, Feliciano; Musarò, Antonio; Sandri, Marco; Rizzuto, Rosario

2016-12-01

Age-related sarcopenia is characterized by a progressive loss of muscle mass with decline in specific force, having dramatic consequences on mobility and quality of life in seniors. The etiology of sarcopenia is multifactorial and underlying mechanisms are currently not fully elucidated. Physical exercise is known to have beneficial effects on muscle trophism and force production. Alterations of mitochondrial Ca 2+ homeostasis regulated by mitochondrial calcium uniporter (MCU) have been recently shown to affect muscle trophism in vivo in mice. To understand the relevance of MCU-dependent mitochondrial Ca 2+ uptake in aging and to investigate the effect of physical exercise on MCU expression and mitochondria dynamics, we analyzed skeletal muscle biopsies from 70-year-old subjects 9 weeks trained with either neuromuscular electrical stimulation (ES) or leg press. Here, we demonstrate that improved muscle function and structure induced by both trainings are linked to increased protein levels of MCU Ultrastructural analyses by electron microscopy showed remodeling of mitochondrial apparatus in ES-trained muscles that is consistent with an adaptation to physical exercise, a response likely mediated by an increased expression of mitochondrial fusion protein OPA1. Altogether these results indicate that the ES-dependent physiological effects on skeletal muscle size and force are associated with changes in mitochondrial-related proteins involved in Ca 2+ homeostasis and mitochondrial shape. These original findings in aging human skeletal muscle confirm the data obtained in mice and propose MCU and mitochondria-related proteins as potential pharmacological targets to counteract age-related muscle loss. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Physiologic oxygen concentration enhances the stem-like properties of CD133+ human glioblastoma cells in vitro.

PubMed

McCord, Amy M; Jamal, Muhammad; Shankavaram, Uma T; Shankavarum, Uma T; Lang, Frederick F; Camphausen, Kevin; Tofilon, Philip J

2009-04-01

In vitro investigations of tumor stem-like cells (TSC) isolated from human glioblastoma (GB) surgical specimens have been done primarily at an atmospheric oxygen level of 20%. To determine whether an oxygen level more consistent with in situ conditions affects their stem cell-like characteristics, we compared GB TSCs grown under conditions of 20% and 7% oxygen. Growing CD133(+) cells sorted from three GB neurosphere cultures at 7% O(2) reduced their doubling time and increased the self-renewal potential as reflected by clonogenicity. Furthermore, at 7% oxygen, the cultures exhibited an enhanced capacity to differentiate along both the glial and neuronal pathways. As compared with 20%, growth at 7% oxygen resulted in an increase in the expression levels of the neural stem cell markers CD133 and nestin as well as the stem cell markers Oct4 and Sox2. In addition, whereas hypoxia inducible factor 1alpha was not affected in CD133(+) TSCs grown at 7% O(2), hypoxia-inducible factor 2alpha was expressed at higher levels as compared with 20% oxygen. Gene expression profiles generated by microarray analysis revealed that reducing oxygen level to 7% resulted in the up-regulation and down-regulation of a significant number of genes, with more than 140 being commonly affected among the three CD133(+) cultures. Furthermore, Gene Ontology categories up-regulated at 7% oxygen included those associated with stem cells or GB TSCs. Thus, the data presented indicate that growth at the more physiologically relevant oxygen level of 7% enhances the stem cell-like phenotype of CD133(+) GB cells.

Physiological processes non-linearly affect electrophysiological recordings during transcranial electric stimulation.

PubMed

Noury, Nima; Hipp, Joerg F; Siegel, Markus

2016-10-15

Transcranial electric stimulation (tES) is a promising tool to non-invasively manipulate neuronal activity in the human brain. Several studies have shown behavioral effects of tES, but stimulation artifacts complicate the simultaneous investigation of neural activity with EEG or MEG. Here, we first show for EEG and MEG, that contrary to previous assumptions, artifacts do not simply reflect stimulation currents, but that heartbeat and respiration non-linearly modulate stimulation artifacts. These modulations occur irrespective of the stimulation frequency, i.e. during both transcranial alternating and direct current stimulations (tACS and tDCS). Second, we show that, although at first sight previously employed artifact rejection methods may seem to remove artifacts, data are still contaminated by non-linear stimulation artifacts. Because of their complex nature and dependence on the subjects' physiological state, these artifacts are prone to be mistaken as neural entrainment. In sum, our results uncover non-linear tES artifacts, show that current techniques fail to fully remove them, and pave the way for new artifact rejection methods. Copyright © 2016 Elsevier Inc. All rights reserved.

Klismaphilia--a physiological perspective.

PubMed

Agnew, J

1982-10-01

Dr. Joanne Denko coined the work klismaphilia to describe the practices of some of her patients who enjoyed the use of enemas as a sexual stimulant. Since then questions occasionally appear in the professional literature asking about the relationship between enemas and sexual pleasure. This paper considers some of the physiological aspects of the human sexual apparatus that relate to anal sensitivity and explores why klismaphilia can be sexually grafifying. The paper starts with a discussion of the physiological basis for anal sensitivity and anal masturbation in both the human male and the human female. The paper then goes on to relate all this to the sexual sensations received from an enema, and discusses the similarities and differences between all these types of stimulation. Some of the psychological aspects of klismaphilia are also considered in relationship to the physiology involved. The paper concludes with a brief discussion of masked anal masturbation among the population at large. A comprehensive list of references from the literature is given to support these findings.

Population Physiologically-Based Pharmacokinetic Modeling for the Human Lactational Transfer of PCB 153 with Consideration of Worldwide Human Biomonitoring Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Redding, Laurel E.; Sohn, Michael D.; McKone, Thomas E.

2008-03-01

We developed a physiologically based pharmacokinetic model of PCB 153 in women, and predict its transfer via lactation to infants. The model is the first human, population-scale lactational model for PCB 153. Data in the literature provided estimates for model development and for performance assessment. Physiological parameters were taken from a cohort in Taiwan and from reference values in the literature. We estimated partition coefficients based on chemical structure and the lipid content in various body tissues. Using exposure data in Japan, we predicted acquired body burden of PCB 153 at an average childbearing age of 25 years and comparemore » predictions to measurements from studies in multiple countries. Forward-model predictions agree well with human biomonitoring measurements, as represented by summary statistics and uncertainty estimates. The model successfully describes the range of possible PCB 153 dispositions in maternal milk, suggesting a promising option for back estimating doses for various populations. One example of reverse dosimetry modeling was attempted using our PBPK model for possible exposure scenarios in Canadian Inuits who had the highest level of PCB 153 in their milk in the world.« less

Affective processes in human-automation interactions.

PubMed

Merritt, Stephanie M

2011-08-01

This study contributes to the literature on automation reliance by illuminating the influences of user moods and emotions on reliance on automated systems. Past work has focused predominantly on cognitive and attitudinal variables, such as perceived machine reliability and trust. However, recent work on human decision making suggests that affective variables (i.e., moods and emotions) are also important. Drawing from the affect infusion model, significant effects of affect are hypothesized. Furthermore, a new affectively laden attitude termed liking is introduced. Participants watched video clips selected to induce positive or negative moods, then interacted with a fictitious automated system on an X-ray screening task At five time points, important variables were assessed including trust, liking, perceived machine accuracy, user self-perceived accuracy, and reliance.These variables, along with propensity to trust machines and state affect, were integrated in a structural equation model. Happiness significantly increased trust and liking for the system throughout the task. Liking was the only variable that significantly predicted reliance early in the task. Trust predicted reliance later in the task, whereas perceived machine accuracy and user self-perceived accuracy had no significant direct effects on reliance at any time. Affective influences on automation reliance are demonstrated, suggesting that this decision-making process may be less rational and more emotional than previously acknowledged. Liking for a new system may be key to appropriate reliance, particularly early in the task. Positive affect can be easily induced and may be a lever for increasing liking.

Procedures of Exercise Physiology Laboratories

NASA Technical Reports Server (NTRS)

Bishop, Phillip A.; Fortney, Suzanne; Greenisen, Michael; Siconolfi, Steven F.; Bamman, Marcas M.; Moore, Alan D., Jr.; Squires, William

1998-01-01

This manual describes the laboratory methods used to collect flight crew physiological performance data at the Johnson Space Center. The Exercise Countermeasures Project Laboratory is a standard physiology laboratory; only the application to the study of human physiological adaptations to spaceflight is unique. In the absence of any other recently published laboratory manual, this manual should be a useful document staffs and students of other laboratories.

Low-shear modeled microgravity: a global environmental regulatory signal affecting bacterial gene expression, physiology, and pathogenesis

NASA Technical Reports Server (NTRS)

Nickerson, Cheryl A.; Ott, C. Mark; Wilson, James W.; Ramamurthy, Rajee; LeBlanc, Carly L.; Honer zu Bentrup, Kerstin; Hammond, Timothy; Pierson, Duane L.

2003-01-01

Bacteria inhabit an impressive variety of ecological niches and must adapt constantly to changing environmental conditions. While numerous environmental signals have been examined for their effect on bacteria, the effects of mechanical forces such as shear stress and gravity have only been investigated to a limited extent. However, several important studies have demonstrated a key role for the environmental signals of low shear and/or microgravity in the regulation of bacterial gene expression, physiology, and pathogenesis [Chem. Rec. 1 (2001) 333; Appl. Microbiol. Biotechnol. 54 (2000) 33; Appl. Environ. Microbiol. 63 (1997) 4090; J. Ind. Microbiol. 18 (1997) 22; Curr. Microbiol. 34(4) (1997) 199; Appl. Microbiol. Biotechnol. 56(3-4) (2001) 384; Infect Immun. 68(6) (2000) 3147; Cell 109(7) (2002) 913; Appl. Environ. Microbiol. 68(11) (2002) 5408; Proc. Natl. Acad. Sci. U. S. A. 99(21) (2002) 13807]. The response of bacteria to these environmental signals, which are similar to those encountered during prokaryotic life cycles, may provide insight into bacterial adaptations to physiologically relevant conditions. This review focuses on the current and potential future research trends aimed at understanding the effect of the mechanical forces of low shear and microgravity analogues on different bacterial parameters. In addition, this review also discusses the use of microgravity technology to generate physiologically relevant human tissue models for research in bacterial pathogenesis.

Zebrafish Bone and General Physiology Are Differently Affected by Hormones or Changes in Gravity.

PubMed

Aceto, Jessica; Nourizadeh-Lillabadi, Rasoul; Marée, Raphael; Dardenne, Nadia; Jeanray, Nathalie; Wehenkel, Louis; Aleström, Peter; van Loon, Jack J W A; Muller, Marc

2015-01-01

Teleost fish such as zebrafish (Danio rerio) are increasingly used for physiological, genetic and developmental studies. Our understanding of the physiological consequences of altered gravity in an entire organism is still incomplete. We used altered gravity and drug treatment experiments to evaluate their effects specifically on bone formation and more generally on whole genome gene expression. By combining morphometric tools with an objective scoring system for the state of development for each element in the head skeleton and specific gene expression analysis, we confirmed and characterized in detail the decrease or increase of bone formation caused by a 5 day treatment (from 5dpf to 10 dpf) of, respectively parathyroid hormone (PTH) or vitamin D3 (VitD3). Microarray transcriptome analysis after 24 hours treatment reveals a general effect on physiology upon VitD3 treatment, while PTH causes more specifically developmental effects. Hypergravity (3g from 5dpf to 9 dpf) exposure results in a significantly larger head and a significant increase in bone formation for a subset of the cranial bones. Gene expression analysis after 24 hrs at 3g revealed differential expression of genes involved in the development and function of the skeletal, muscular, nervous, endocrine and cardiovascular systems. Finally, we propose a novel type of experimental approach, the "Reduced Gravity Paradigm", by keeping the developing larvae at 3g hypergravity for the first 5 days before returning them to 1g for one additional day. 5 days exposure to 3g during these early stages also caused increased bone formation, while gene expression analysis revealed a central network of regulatory genes (hes5, sox10, lgals3bp, egr1, edn1, fos, fosb, klf2, gadd45ba and socs3a) whose expression was consistently affected by the transition from hyper- to normal gravity.

Zebrafish Bone and General Physiology Are Differently Affected by Hormones or Changes in Gravity

PubMed Central

Aceto, Jessica; Nourizadeh-Lillabadi, Rasoul; Marée, Raphael; Dardenne, Nadia; Jeanray, Nathalie; Wehenkel, Louis; Aleström, Peter

2015-01-01

Teleost fish such as zebrafish (Danio rerio) are increasingly used for physiological, genetic and developmental studies. Our understanding of the physiological consequences of altered gravity in an entire organism is still incomplete. We used altered gravity and drug treatment experiments to evaluate their effects specifically on bone formation and more generally on whole genome gene expression. By combining morphometric tools with an objective scoring system for the state of development for each element in the head skeleton and specific gene expression analysis, we confirmed and characterized in detail the decrease or increase of bone formation caused by a 5 day treatment (from 5dpf to 10 dpf) of, respectively parathyroid hormone (PTH) or vitamin D3 (VitD3). Microarray transcriptome analysis after 24 hours treatment reveals a general effect on physiology upon VitD3 treatment, while PTH causes more specifically developmental effects. Hypergravity (3g from 5dpf to 9 dpf) exposure results in a significantly larger head and a significant increase in bone formation for a subset of the cranial bones. Gene expression analysis after 24 hrs at 3g revealed differential expression of genes involved in the development and function of the skeletal, muscular, nervous, endocrine and cardiovascular systems. Finally, we propose a novel type of experimental approach, the "Reduced Gravity Paradigm", by keeping the developing larvae at 3g hypergravity for the first 5 days before returning them to 1g for one additional day. 5 days exposure to 3g during these early stages also caused increased bone formation, while gene expression analysis revealed a central network of regulatory genes (hes5, sox10, lgals3bp, egr1, edn1, fos, fosb, klf2, gadd45ba and socs3a) whose expression was consistently affected by the transition from hyper- to normal gravity. PMID:26061167

Comparative Physiology of Fatigue.

PubMed

Jones, James H

2016-11-01

This review attempts to provide insights into factors associated with fatigue in human and nonhuman animals by using the two fundamental approaches of comparative physiology: determining common principles that govern structure and function in animals that are relatively invariant between animals and evaluating animals that have been highly adapted by natural selection to demonstrate extreme performance. In this review, I approach the topic of fatigue by considering factors that are associated with its reciprocal or inverse or duration of sustained performance before fatigue sets in to end the performance. The two general factors that I consider that affect endurance time more than any other are body temperature and body mass. The former affects endurance time because of thermodynamic effects on chemical reaction rates and metabolism; the latter acts through the mechanism of allometry or scaling. The examples of extreme animal performance that I discuss are two examples of bird migration, the diving performance of marine mammals, and the unique relationship that governs energy cost of locomotion in hopping kangaroos.

Preliminary results of Physiological plant growth modelling for human life support in space

NASA Astrophysics Data System (ADS)

Sasidharan L, Swathy; Dussap, Claude-Gilles; Hezard, Pauline

2012-07-01

Human life support is fundamental and crucial in any kind of space explorations. MELiSSA project of European Space Agency aims at developing a closed, artificial ecological life support system involving human, plants and micro organisms. Consuming carbon dioxide and water from the life support system, plants grow in one of the chambers and convert it into food and oxygen along with potable water. The environmental conditions, nutrient availability and its consumption of plants should be studied and necessarily modeled to predict the amount of food, oxygen and water with respect to the environmental changes and limitations. The reliability of a completely closed system mainly depends on the control laws and strategies used. An efficient control can occur, only if the system to control is itself well known, described and ideally if the responses of the system to environmental changes are predictable. In this aspect, the general structure of plant growth model has been designed together with physiological modelling.The physiological model consists of metabolic models of leaves, stem and roots, of which concern specific metabolisms of the associated plant parts. On the basis of the carbon source transport (eg. sucrose) through stem, the metabolic models (leaf and root) can be interconnected to each other and finally coupled to obtain the entire plant model. For the first step, leaf metabolic model network was built using stoichiometric, mass and energy balanced metabolic equations under steady state approach considering all necessary plant pathways for growth and maintenance of leaves. As the experimental data for lettuce plants grown in closed and controlled environmental chambers were available, the leaf metabolic model has been established for lettuce leaves. The constructed metabolic network is analyzed using known stoichiometric metabolic technique called metabolic flux analysis (MFA). Though, the leaf metabolic model alone is not sufficient to achieve the

Human Enteroids as a Model of Upper Small Intestinal Ion Transport Physiology and Pathophysiology.

PubMed

Foulke-Abel, Jennifer; In, Julie; Yin, Jianyi; Zachos, Nicholas C; Kovbasnjuk, Olga; Estes, Mary K; de Jonge, Hugo; Donowitz, Mark

2016-03-01

Human intestinal crypt-derived enteroids are a model of intestinal ion transport that require validation by comparison with cell culture and animal models. We used human small intestinal enteroids to study neutral Na(+) absorption and stimulated fluid and anion secretion under basal and regulated conditions in undifferentiated and differentiated cultures to show their functional relevance to ion transport physiology and pathophysiology. Human intestinal tissue specimens were obtained from an endoscopic biopsy or surgical resections performed at Johns Hopkins Hospital. Crypts were isolated, enteroids were propagated in culture, induced to undergo differentiation, and transduced with lentiviral vectors. Crypt markers, surface cell enzymes, and membrane ion transporters were characterized using quantitative reverse-transcription polymerase chain reaction, immunoblot, or immunofluorescence analyses. We used multiphoton and time-lapse confocal microscopy to monitor intracellular pH and luminal dilatation in enteroids under basal and regulated conditions. Enteroids differentiated upon withdrawal of WNT3A, yielding decreased crypt markers and increased villus-like characteristics. Na(+)/H(+) exchanger 3 activity was similar in undifferentiated and differentiated enteroids, and was affected by known inhibitors, second messengers, and bacterial enterotoxins. Forskolin-induced swelling was completely dependent on cystic fibrosis transmembrane conductance regulator and partially dependent on Na(+)/H(+) exchanger 3 and Na(+)/K(+)/2Cl(-) cotransporter 1 inhibition in undifferentiated and differentiated enteroids. Increases in cyclic adenosine monophosphate with forskolin caused enteroid intracellular acidification in HCO3(-)-free buffer. Cyclic adenosine monophosphate-induced enteroid intracellular pH acidification as part of duodenal HCO3(-) secretion appears to require cystic fibrosis transmembrane conductance regulator and electrogenic Na(+)/HCO3(-) cotransporter 1

Understanding Protein Synthesis: A Role-Play Approach in Large Undergraduate Human Anatomy and Physiology Classes

ERIC Educational Resources Information Center

Sturges, Diana; Maurer, Trent W.; Cole, Oladipo

2009-01-01

This study investigated the effectiveness of role play in a large undergraduate science class. The targeted population consisted of 298 students enrolled in 2 sections of an undergraduate Human Anatomy and Physiology course taught by the same instructor. The section engaged in the role-play activity served as the study group, whereas the section…

Ocean acidification does not affect the physiology of the tropical coral Acropora digitifera during a 5-week experiment

NASA Astrophysics Data System (ADS)

Takahashi, A.; Kurihara, H.

2013-03-01

The increase in atmospheric CO2 concentration, which has resulted from the burning of fossil fuels, is being absorbed by the oceans and is causing ocean acidification. Ocean acidification involves the decrease of both the pH and the calcium carbonate saturation state. Ocean acidification is predicted to impact the physiology of marine organisms and reduce the calcification rates of corals. In the present study, we measured the rates of calcification, respiration, photosynthesis, and zooxanthellae density of the tropical coral Acropora digitifera under near-natural summertime temperature and sunlight for a 5-week period. We found that these key physiological parameters were not affected by both mid-CO2 (pCO2 = 744 ± 38, pH = 7.97 ± 0.02, Ωarag = 2.6 ± 0.1) and high-CO2 conditions (pCO2 = 2,142 ± 205, pH = 7.56 ± 0.04, Ωarag = 1.1 ± 0.2) throughout the 35 days experimental period. Additionally, there was no significant correlation between calcification rate and seawater aragonite saturation (Ωarag). These results suggest that the impacts of ocean acidification on corals physiology may be more complex than have been previously proposed.

Genetic Alterations Affecting Cholesterol Metabolism and Human Fertility1

PubMed Central

DeAngelis, Anthony M.; Roy-O'Reilly, Meaghan; Rodriguez, Annabelle

2014-01-01

ABSTRACT Single nucleotide polymorphisms (SNPs) represent genetic variations among individuals in a population. In medicine, these small variations in the DNA sequence may significantly impact an individual's response to certain drugs or influence the risk of developing certain diseases. In the field of reproductive medicine, a significant amount of research has been devoted to identifying polymorphisms which may impact steroidogenesis and fertility. This review discusses current understanding of the effects of genetic variations in cholesterol metabolic pathways on human fertility that bridge novel linkages between cholesterol metabolism and reproductive health. For example, the role of the low-density lipoprotein receptor (LDLR) in cellular metabolism and human reproduction has been well studied, whereas there is now an emerging body of research on the role of the high-density lipoprotein (HDL) receptor scavenger receptor class B type I (SR-BI) in human lipid metabolism and female reproduction. Identifying and understanding how polymorphisms in the SCARB1 gene or other genes related to lipid metabolism impact human physiology is essential and will play a major role in the development of personalized medicine for improved diagnosis and treatment of infertility. PMID:25122065

Physiological serum copper concentrations found in malignancies cause unfolding induced aggregation of human serum albumin in vitro.

PubMed

Rizvi, Asim; Furkan, Mohd; Naseem, Imrana

2017-12-15

Malignancies are characterized by several drastic metabolic changes, one of which is a progressive rise in the levels of serum copper. This rise in serum copper is documented across all malignancies and across malignancies in several species. This study aims to explore in vitro the effect of increased copper levels on the structure of the blood protein human serum albumin. Exposure of human serum albumin to physiologically relevant copper concentrations for 21 days resulted in structural modifications in the protein which were evident by changes in the intrinsic florescence. A loss of the predominantly alpha helical structure of human serum albumin was recorded along with a tendency to form protein aggregates. This aggregation was characterized by Thioflavin T and Congo Red assays. Rayleigh light scattering and turbidity assays confirmed aggregation. The aggregates were visually confirmed using transmission electron microscopy. This is the first report implicating increased copper levels as a cause of aggregation of blood proteins in malignancies. The physiological and biochemical implications of this phenomenon are discussed. Copyright © 2017. Published by Elsevier Inc.

Relationship between sociability toward humans and physiological stress in dogs.

PubMed

Shin, Yoon-Joo; Shin, Nam-Shik

2017-07-28

Sociability is an essential trait for dogs to successfully interact with humans. In this study, the relationship between sociability and physiological stress was examined. Additionally, whether differences exist between companion dogs (C group) and shelter dogs (S group) was examined. Overall, healthy 37 dogs (C group=21 and S group=16) were examined. After 5 min of walking, the dog and the owner (or the chief manager) rested freely in the experimental location for 5 min. The behavioral test with 6 categories was conducted to evaluate sociability over 4 min. The establishment of two groups (H group=dogs with high sociability; L group=dogs with low sociability) was supported by the statistical results of the behavioral tests. Saliva was collected before (P1) and after the test period (P2), and salivary cortisol levels were determined and statistically analyzed. The cortisol concentrations at P2 and the differences in concentrations between P1 and P2 (P2-P1) in the groups with high sociability were significantly lower than those in the groups with low sociability. These results may demonstrate that sociable dogs adapt more comfortably to strangers and unfamiliar situations. Meanwhile, there were significant differences in hormonal results between the C and S groups. For this reason, their sociability should be evaluated using behavioral and physiological assessments before re-adoption to ensure their successful adaptation.

The emergence of Applied Physiology within the discipline of Physiology.

PubMed

Tipton, Charles M

2016-08-01

Despite the availability and utilization of the physiology textbooks authored by Albrecht von Haller during the 18th century that heralded the modern age of physiology, not all physicians or physiologists were satisfied with its presentation, contents, or application to medicine. Initial reasons were fundamental disagreements between the "mechanists," represented by Boerhaave, Robinson, and von Haller, and the "vitalists," represented by the faculty and graduates of the Montpellier School of Medicine in France, notably, Bordeu and Barthez. Subsequently, objections originated from Europe, United Kingdom, and the United States in publications that focused not only on the teaching of physiology to medical and secondary students, but on the specific applications of the content of physiology to medicine, health, hygiene, pathology, and chronic diseases. At the turn of the 20th century, texts began to appear with applied physiology in their titles and in 1926, physician Samson Wright published a textbook entitled Applied Physiology that was intended for both medical students and the medical profession. Eleven years later, physicians Best and Taylor published The Physiological Basis of Medical Practice: A University of Toronto Texbook in Applied Physiology Although both sets of authors defined the connection between applied physiology and physiology, they failed to define the areas of physiology that were included within applied physiology. This was accomplished by the American Physiological Society (APS) Publications Committee in 1948 with the publication of the Journal of Appplied Physiology, that stated the word "applied" would broadly denote human physiology whereas the terms stress and environment would broadly include work, exercise, plus industrial, climatic and social factors. NIH established a study section (SS) devoted to applied physiology in 1964 which remained active until 2001 when it became amalgamated into other SSs. Before the end of the 20th century when

Age effects on preattentive and early attentive auditory processing of redundant stimuli: is sensory gating affected by physiological aging?

PubMed

Gmehlin, Dennis; Kreisel, Stefan H; Bachmann, Silke; Weisbrod, Matthias; Thomas, Christine

2011-10-01

The frontal hypothesis of aging predicts an age-related decline in cognitive functions requiring inhibitory or attentional regulation. In Alzheimer's disease, preattentive gating out of redundant information is impaired. Our study aimed to examine changes associated with physiological aging in both pre- and early attentive inhibition of recurrent acoustic information. Using a passive double-click paradigm, we recorded mid-latency (P30-P50) and late-latency (N100 and P200) evoked potentials in healthy young (26 ± 5 years) and healthy elderly subjects (72 ± 5 years). Physiological aging did not affect auditory gating in amplitude measures. Both age groups exhibited clear inhibition in preattentive P50 and attention-modulated (N100) components, whereas P30 was not attenuated. Irrespective of age, the magnitude of inhibition differed significantly, being most pronounced for N100 gating. Inhibition of redundant information seems to be preserved with physiological aging. Early attentive N100 gating showed the maximum effect. Further studies are warranted to evaluate sensory gating as a suitable biomarker of underlying neurodegenerative disease.

The Virtual Physiological Human ToolKit.

PubMed

Cooper, Jonathan; Cervenansky, Frederic; De Fabritiis, Gianni; Fenner, John; Friboulet, Denis; Giorgino, Toni; Manos, Steven; Martelli, Yves; Villà-Freixa, Jordi; Zasada, Stefan; Lloyd, Sharon; McCormack, Keith; Coveney, Peter V

2010-08-28

The Virtual Physiological Human (VPH) is a major European e-Science initiative intended to support the development of patient-specific computer models and their application in personalized and predictive healthcare. The VPH Network of Excellence (VPH-NoE) project is tasked with facilitating interaction between the various VPH projects and addressing issues of common concern. A key deliverable is the 'VPH ToolKit'--a collection of tools, methodologies and services to support and enable VPH research, integrating and extending existing work across Europe towards greater interoperability and sustainability. Owing to the diverse nature of the field, a single monolithic 'toolkit' is incapable of addressing the needs of the VPH. Rather, the VPH ToolKit should be considered more as a 'toolbox' of relevant technologies, interacting around a common set of standards. The latter apply to the information used by tools, including any data and the VPH models themselves, and also to the naming and categorizing of entities and concepts involved. Furthermore, the technologies and methodologies available need to be widely disseminated, and relevant tools and services easily found by researchers. The VPH-NoE has thus created an online resource for the VPH community to meet this need. It consists of a database of tools, methods and services for VPH research, with a Web front-end. This has facilities for searching the database, for adding or updating entries, and for providing user feedback on entries. Anyone is welcome to contribute.

An integrated physiology model to study regional lung damage effects and the physiologic response

PubMed Central

2014-01-01

Background This work expands upon a previously developed exercise dynamic physiology model (DPM) with the addition of an anatomic pulmonary system in order to quantify the impact of lung damage on oxygen transport and physical performance decrement. Methods A pulmonary model is derived with an anatomic structure based on morphometric measurements, accounting for heterogeneous ventilation and perfusion observed experimentally. The model is incorporated into an existing exercise physiology model; the combined system is validated using human exercise data. Pulmonary damage from blast, blunt trauma, and chemical injury is quantified in the model based on lung fluid infiltration (edema) which reduces oxygen delivery to the blood. The pulmonary damage component is derived and calibrated based on published animal experiments; scaling laws are used to predict the human response to lung injury in terms of physical performance decrement. Results The augmented dynamic physiology model (DPM) accurately predicted the human response to hypoxia, altitude, and exercise observed experimentally. The pulmonary damage parameters (shunt and diffusing capacity reduction) were fit to experimental animal data obtained in blast, blunt trauma, and chemical damage studies which link lung damage to lung weight change; the model is able to predict the reduced oxygen delivery in damage conditions. The model accurately estimates physical performance reduction with pulmonary damage. Conclusions We have developed a physiologically-based mathematical model to predict performance decrement endpoints in the presence of thoracic damage; simulations can be extended to estimate human performance and escape in extreme situations. PMID:25044032

The physiology of altered eating behaviour after Roux-en-Y gastric bypass.

PubMed

le Roux, Carel W; Bueter, Marco

2014-09-01

Obesity and its related comorbidities can be detrimental for the affected individual, as well as constituting a major challenge to public health systems worldwide. Currently, the most effective treatment option leading to clinically significant and maintained body weight loss and reduction in obesity-related morbidity and mortality is obesity surgery, which is recommended for patients with a body mass index of >40 kg m(-2), or >35 kg m(-2) if obesity-associated comorbidities, such as type 2 diabetes mellitus, are present. This report focuses on the altered eating behaviour after the most common of these operations, the Roux-en-Y gastric bypass. Animal and human experiments designed to understand the underlying physiological mechanisms of altered taste and appetite are discussed. © 2014 The Authors. Experimental Physiology © 2014 The Physiological Society.

Combining Chimeric Mice with Humanized Liver, Mass Spectrometry, and Physiologically-Based Pharmacokinetic Modeling in Toxicology.

PubMed

Yamazaki, Hiroshi; Suemizu, Hiroshi; Mitsui, Marina; Shimizu, Makiko; Guengerich, F Peter

2016-12-19

Species differences exist in terms of drug oxidation activities, which are mediated mainly by cytochrome P450 (P450) enzymes. To overcome the problem of species extrapolation, transchromosomic mice containing a human P450 3A cluster or chimeric mice transplanted with human hepatocytes have been introduced into the human toxicology research area. In this review, drug metabolism and disposition mediated by humanized livers in chimeric mice are summarized in terms of biliary/urinary excretions of phthalate and bisphenol A and plasma clearances of the human cocktail probe drugs caffeine, warfarin, omeprazole, metoprolol, and midazolam. Simulation of human plasma concentrations of the teratogen thalidomide and its human metabolites is possible with a simplified physiologically based pharmacokinetic model based on data obtained in chimeric mice, in accordance with reported clinical thalidomide concentrations. In addition, in vivo nonspecific hepatic protein binding parameters of metabolically activated 14 C-drug candidate and hepatotoxic medicines in humanized liver mice can be analyzed by accelerator mass spectrometry and are useful for predictions in humans.

Psychological and physiological human responses to simulated and real environments: A comparison between Photographs, 360° Panoramas, and Virtual Reality.

PubMed

Higuera-Trujillo, Juan Luis; López-Tarruella Maldonado, Juan; Llinares Millán, Carmen

2017-11-01

Psychological research into human factors frequently uses simulations to study the relationship between human behaviour and the environment. Their validity depends on their similarity with the physical environments. This paper aims to validate three environmental-simulation display formats: photographs, 360° panoramas, and virtual reality. To do this we compared the psychological and physiological responses evoked by simulated environments set-ups to those from a physical environment setup; we also assessed the users' sense of presence. Analysis show that 360° panoramas offer the closest to reality results according to the participants' psychological responses, and virtual reality according to the physiological responses. Correlations between the feeling of presence and physiological and other psychological responses were also observed. These results may be of interest to researchers using environmental-simulation technologies currently available in order to replicate the experience of physical environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of temperament and responsiveness towards humans on the behavior, physiology and milk production of multi-parous dairy cows in a familiar and novel milking environment.

PubMed

Sutherland, Mhairi A; Rogers, Andrea R; Verkerk, Gwyneth A

2012-10-10

The objectives of this study were to investigate whether; 1) temperament or 2) behavioral responsiveness to humans, can affect the behavior, physiology and productivity of dairy cows being milked in a familiar and novel milking environment. Temperament of multi-parous cows was defined based on exit time from a restraint device, as High Responders (HR; n=10), Medium Responders (MR; n=10) or Low Responders (LR; n=10). The behavioral response of cows to humans was assessed using four tests: restraint, exit speed, avoidance distance test and a voluntary approach test. Cows were milked according to their established routines in a rotary (familiar) milking parlor and behavioral, physiological and production data were collected over five consecutive days, including heart rate, cortisol and oxytocin concentrations and milk yield. The following week, cows were milked in a novel environment (herringbone parlor within the same farm facility) over five consecutive days, and the data and sample collection program was repeated. Cows were then given an exogenous adrenocorticotropic hormone (ACTH) challenge to measure adrenal responsiveness. Exit time was negatively correlated with the behavioral responses of cows to restraint and human avoidance distance (HAD) in the paddock and arena. The behavioral response of cows to the milking process was greater in MR than LR and HR cows in the familiar and novel milking environments. Milk yields were greater in LR than HR cows in the novel but not the familiar milking parlor. Oxytocin concentrations increased during milking in the novel environment, regardless of cow temperament. In the familiar and novel environments, heart rates were higher in HR than LR cows before and during milking and rMSSD was lower in HR cows during milking in a novel environment. There was no difference in cortisol concentrations between LR and HR cows in response to an ACTH challenge, but HR cows had higher baseline cortisol levels than LR cows. The number of leg

HuPSON: the human physiology simulation ontology.

PubMed

Gündel, Michaela; Younesi, Erfan; Malhotra, Ashutosh; Wang, Jiali; Li, Hui; Zhang, Bijun; de Bono, Bernard; Mevissen, Heinz-Theodor; Hofmann-Apitius, Martin

2013-11-22

Large biomedical simulation initiatives, such as the Virtual Physiological Human (VPH), are substantially dependent on controlled vocabularies to facilitate the exchange of information, of data and of models. Hindering these initiatives is a lack of a comprehensive ontology that covers the essential concepts of the simulation domain. We propose a first version of a newly constructed ontology, HuPSON, as a basis for shared semantics and interoperability of simulations, of models, of algorithms and of other resources in this domain. The ontology is based on the Basic Formal Ontology, and adheres to the MIREOT principles; the constructed ontology has been evaluated via structural features, competency questions and use case scenarios.The ontology is freely available at: http://www.scai.fraunhofer.de/en/business-research-areas/bioinformatics/downloads.html (owl files) and http://bishop.scai.fraunhofer.de/scaiview/ (browser). HuPSON provides a framework for a) annotating simulation experiments, b) retrieving relevant information that are required for modelling, c) enabling interoperability of algorithmic approaches used in biomedical simulation, d) comparing simulation results and e) linking knowledge-based approaches to simulation-based approaches. It is meant to foster a more rapid uptake of semantic technologies in the modelling and simulation domain, with particular focus on the VPH domain.

HuPSON: the human physiology simulation ontology

PubMed Central

2013-01-01

Background Large biomedical simulation initiatives, such as the Virtual Physiological Human (VPH), are substantially dependent on controlled vocabularies to facilitate the exchange of information, of data and of models. Hindering these initiatives is a lack of a comprehensive ontology that covers the essential concepts of the simulation domain. Results We propose a first version of a newly constructed ontology, HuPSON, as a basis for shared semantics and interoperability of simulations, of models, of algorithms and of other resources in this domain. The ontology is based on the Basic Formal Ontology, and adheres to the MIREOT principles; the constructed ontology has been evaluated via structural features, competency questions and use case scenarios. The ontology is freely available at: http://www.scai.fraunhofer.de/en/business-research-areas/bioinformatics/downloads.html (owl files) and http://bishop.scai.fraunhofer.de/scaiview/ (browser). Conclusions HuPSON provides a framework for a) annotating simulation experiments, b) retrieving relevant information that are required for modelling, c) enabling interoperability of algorithmic approaches used in biomedical simulation, d) comparing simulation results and e) linking knowledge-based approaches to simulation-based approaches. It is meant to foster a more rapid uptake of semantic technologies in the modelling and simulation domain, with particular focus on the VPH domain. PMID:24267822

Recent developments in affective recommender systems

NASA Astrophysics Data System (ADS)

Katarya, Rahul; Verma, Om Prakash

2016-11-01

Recommender systems (RSs) are playing a significant role since 1990s as they provide relevant, personalized information to the users over the internet. Lots of work have been done in information filtering, utilization, and application related to RS. However, an important area recently draws our attention which is affective recommender system. Affective recommender system (ARS) is latest trending area of research, as publication in this domain are few and recently published. ARS is associated with human behaviour, human factors, mood, senses, emotions, facial expressions, body gesture and physiological with human-computer interaction (HCI). Due to this assortment and various interests, more explanation is required, as it is in premature phase and growing as compared to other fields. So we have done literature review (LR) in the affective recommender systems by doing classification, incorporate reputed articles published from the year 2003 to February 2016. We include articles which highlight, analyse, and perform a study on affective recommender systems. This article categorizes, synthesizes, and discusses the research and development in ARS. We have classified and managed ARS papers according to different perspectives: research gaps, nature, algorithm or method adopted, datasets, the platform on executed, types of information and evaluation techniques applied. The researchers and professionals will positively support this survey article for understanding the current position, research in affective recommender systems and will guide future trends, opportunity and research focus in ARS.

Human thermal physiological and psychological responses under different heating environments.

PubMed

Wang, Zhaojun; Ning, Haoran; Ji, Yuchen; Hou, Juan; He, Yanan

2015-08-01

Anecdotal evidence suggests that many residents of severely cold areas of China who use floor heating (FH) systems feel warmer but drier compared to those using radiant heating (RH) systems. However, this phenomenon has not been verified experimentally. In order to validate the empirical hypothesis, and research the differences of human physiological and psychological responses in these two asymmetrical heating environments, an experiment was designed to mimic FH and RH systems. The subjects participating in the experiment were volunteer college-students. During the experiment, the indoor air temperature, air speed, relative humidity, globe temperature, and inner surface temperatures were measured, and subjects' heart rate, blood pressure and skin temperatures were recorded. The subjects were required to fill in questionnaires about their thermal responses during testing. The results showed that the subjects' skin temperatures, heart rate and blood pressure were significantly affected by the type of heating environment. Ankle temperature had greatest impact on overall thermal comfort relative to other body parts, and a slightly cool FH condition was the most pleasurable environment for sedentary subjects. The overall thermal sensation, comfort and acceptability of FH were higher than that of RH. However, the subjects of FH felt drier than that of RH, although the relative humidity in FH environments was higher than that of the RH environment. In future environmental design, the thermal comfort of the ankles should be scrutinized, and a FH cool condition is recommended as the most comfortable thermal environment for office workers. Consequently, large amounts of heating energy could be saved in this area in the winter. The results of this study may lead to more efficient energy use for office or home heating systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Graphical Representation of the Digital Astronaut Physiology Backbone

NASA Technical Reports Server (NTRS)

Briers, Demarcus

2010-01-01

This report summarizes my internship project with the NASA Digital Astronaut Project to analyze the Digital Astronaut (DA) physiology backbone model. The Digital Astronaut Project (DAP) applies integrated physiology models to support space biomedical operations, and to assist NASA researchers in closing knowledge gaps related to human physiologic responses to space flight. The DA physiology backbone is a set of integrated physiological equations and functions that model the interacting systems of the human body. The current release of the model is HumMod (Human Model) version 1.5 and was developed over forty years at the University of Mississippi Medical Center (UMMC). The physiology equations and functions are scripted in an XML schema specifically designed for physiology modeling by Dr. Thomas G. Coleman at UMMC. Currently it is difficult to examine the physiology backbone without being knowledgeable of the XML schema. While investigating and documenting the tags and algorithms used in the XML schema, I proposed a standard methodology for a graphical representation. This standard methodology may be used to transcribe graphical representations from the DA physiology backbone. In turn, the graphical representations can allow examination of the physiological functions and equations without the need to be familiar with the computer programming languages or markup languages used by DA modeling software.

Zoonotic helminths affecting the human eye

PubMed Central

2011-01-01

Nowaday, zoonoses are an important cause of human parasitic diseases worldwide and a major threat to the socio-economic development, mainly in developing countries. Importantly, zoonotic helminths that affect human eyes (HIE) may cause blindness with severe socio-economic consequences to human communities. These infections include nematodes, cestodes and trematodes, which may be transmitted by vectors (dirofilariasis, onchocerciasis, thelaziasis), food consumption (sparganosis, trichinellosis) and those acquired indirectly from the environment (ascariasis, echinococcosis, fascioliasis). Adult and/or larval stages of HIE may localize into human ocular tissues externally (i.e., lachrymal glands, eyelids, conjunctival sacs) or into the ocular globe (i.e., intravitreous retina, anterior and or posterior chamber) causing symptoms due to the parasitic localization in the eyes or to the immune reaction they elicit in the host. Unfortunately, data on HIE are scant and mostly limited to case reports from different countries. The biology and epidemiology of the most frequently reported HIE are discussed as well as clinical description of the diseases, diagnostic considerations and video clips on their presentation and surgical treatment. Homines amplius oculis, quam auribus credunt Seneca Ep 6,5 Men believe their eyes more than their ears PMID:21429191

The Fire-Walker’s High: Affect and Physiological Responses in an Extreme Collective Ritual

PubMed Central

Fischer, Ronald; Xygalatas, Dimitris; Mitkidis, Panagiotis; Reddish, Paul; Tok, Penny; Konvalinka, Ivana; Bulbulia, Joseph

2014-01-01

How do people feel during extreme collective rituals? Despite longstanding speculation, few studies have attempted to quantify ritual experiences. Using a novel pre/post design, we quantified physiological fluctuations (heart rates) and self-reported affective states from a collective fire-walking ritual in a Mauritian Hindu community. Specifically, we compared changes in levels of happiness, fatigue, and heart rate reactivity among high-ordeal participants (fire-walkers), low-ordeal participants (non-fire-walking participants with familial bonds to fire-walkers) and spectators (unrelated/unknown to the fire-walkers). We observed that fire-walkers experienced the highest increase in heart rate and reported greater happiness post-ritual compared to low-ordeal participants and spectators. Low-ordeal participants reported increased fatigue after the ritual compared to both fire-walkers and spectators, suggesting empathetic identification effects. Thus, witnessing the ritualistic suffering of loved ones may be more exhausting than experiencing suffering oneself. The findings demonstrate that the level of ritual involvement is important for shaping affective responses to collective rituals. Enduring a ritual ordeal is associated with greater happiness, whereas observing a loved-one endure a ritual ordeal is associated with greater fatigue post-ritual. PMID:24586315

Cortisol as a Biomarker of Stress in Term Human Labor: Physiological and Methodological Issues

PubMed Central

Newton, Edward R.; Tanner, Charles J.; Heitkemper, Margaret M.

2013-01-01

Literature on the use of plasma cortisol to quantify psychophysiological stress in humans is extensive. However, in parturition at term gestation the use of cortisol as a biomarker of stress is particularly complex. Plasma cortisol levels increase as labor progresses. This increase seems to be important for maintenance of maternal/fetal wellbeing and facilitation of normal labor progress. Unique physiological and methodological issues involved in the use of cortisol as a biomarker of stress in labor present challenges for researchers. This review examines these issues, suggests mixed methods and within-subject repeated measures designs, and offers recommendations for assay procedures for parturient sampling. Documentation of clinical interventions and delivery outcomes may elucidate relationships among psychophysiological stressors, cortisol and normal labor progress. With attention to these methodological issues, analysis of plasma cortisol may lead to clinical interventions that support normal labor physiology. PMID:23338011

Do 'mind over muscle' strategies work? Examining the effects of attentional association and dissociation on exertional, affective and physiological responses to exercise.

PubMed

Lind, Erik; Welch, Amy S; Ekkekakis, Panteleimon

2009-01-01

Despite the well established physical and psychological benefits derived from leading a physically active life, rates of sedentary behaviour remain high. Dropout and non-compliance are major contributors to the problem of physical inactivity. Perceptions of exertion, affective responses (e.g. displeasure or discomfort), and physiological stress could make the exercise experience aversive, particularly for beginners. Shifting one's attentional focus towards environmental stimuli (dissociation) instead of one's body (association) has been theorized to enhance psychological responses and attenuate physiological stress. Research evidence on the effectiveness of attentional focus strategies, however, has been perplexing, covering the entire gamut of possible outcomes (association and dissociation having been shown to be both effective and ineffective). This article examines the effects of manipulations of attentional focus on exertional and affective responses, as well as on exercise economy and tolerance. The possible roles of the characteristics of the exercise stimulus (intensity, duration) and the exercise participants, methodological issues, and limitations of experimental designs are discussed. In particular, the critical role of exercise intensity is emphasized. Dissociative strategies may be more effective in reducing perceptions of exertion and enhancing affective responses at low to moderate exercise intensities, but their effectiveness may be diminished at higher and near-maximal levels, at which physiological cues dominate. Conversely, associative strategies could enable the exerciser to regulate intensity to avoid injury or overexertion. Thus, depending on intensity, both strategies have a place in the 'toolbox' of the public health or exercise practitioner as methods of enhancing the exercise experience and promoting long-term compliance.

Improving the physiological realism of experimental models.

PubMed

Vinnakota, Kalyan C; Cha, Chae Y; Rorsman, Patrik; Balaban, Robert S; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A; Jeneson, Jeroen A L

2016-04-06

The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease.

Affective Biases in Humans and Animals.

PubMed

Robinson, E S J; Roiser, J P

Depression is one of the most common but poorly understood psychiatric conditions. Although drug treatments and psychological therapies are effective in some patients, many do not achieve full remission and some patients receive no apparent benefit. Developing new improved treatments requires a better understanding of the aetiology of symptoms and evaluation of novel therapeutic targets in pre-clinical studies. Recent developments in our understanding of the basic cognitive processes that may contribute to the development of depression and its treatment offer new opportunities for both clinical and pre-clinical research. This chapter discusses the clinical evidence supporting a cognitive neuropsychological model of depression and antidepressant efficacy, and how this information may be usefully translated to pre-clinical investigation. Studies using neuropsychological tests in depressed patients and at risk populations have revealed basic negative emotional biases and disrupted reward and punishment processing, which may also impact on non-affective cognition. These affective biases are sensitive to antidepressant treatments with early onset effects observed, suggesting an important role in recovery. This clinical work into affective biases has also facilitated back-translation to animals and the development of assays to study affective biases in rodents. These animal studies suggest that, similar to humans, rodents in putative negative affective states exhibit negative affective biases on decision-making and memory tasks. Antidepressant treatments also induce positive biases in these rodent tasks, supporting the translational validity of this approach. Although still in the early stages of development and validation, affective biases in depression have the potential to offer new insights into the clinical condition, as well as facilitating the development of more translational approaches for pre-clinical studies.

Human and rodent aryl hydrocarbon receptor (AHR): from mediator of dioxin toxicity to physiologic AHR functions and therapeutic options.

PubMed

Bock, Karl Walter

2017-04-01

Metabolism of aryl hydrocarbons and toxicity of dioxins led to the discovery of the aryl hydrocarbon receptor (AHR). Tremendous advances have been made on multiplicity of AHR signaling and identification of endogenous ligands including the tryptophan metabolites FICZ and kynurenine. However, human AHR functions are still poorly understood due to marked species differences as well as cell-type- and cell context-dependent AHR functions. Observations in dioxin-poisoned individuals may provide hints to physiologic AHR functions in humans. Based on these observations three human AHR functions are discussed: (1) Chemical defence and homeostasis of endobiotics. The AHR variant Val381 in modern humans leads to reduced AHR affinity to aryl hydrocarbons in comparison with Neanderthals and primates expressing the Ala381 variant while affinity to indoles remains unimpaired. (2) Homeostasis of stem/progenitor cells. Dioxins dysregulate homeostasis in sebocyte stem cells. (3) Modulation of immunity. In addition to microbial defence, AHR may be involved in a 'disease tolerance defence pathway'. Further characterization of physiologic AHR functions may lead to therapeutic options.

Neural evidence that human emotions share core affective properties.

PubMed

Wilson-Mendenhall, Christine D; Barrett, Lisa Feldman; Barsalou, Lawrence W

2013-06-01

Research on the "emotional brain" remains centered around the idea that emotions like fear, happiness, and sadness result from specialized and distinct neural circuitry. Accumulating behavioral and physiological evidence suggests, instead, that emotions are grounded in core affect--a person's fluctuating level of pleasant or unpleasant arousal. A neuroimaging study revealed that participants' subjective ratings of valence (i.e., pleasure/displeasure) and of arousal evoked by various fear, happiness, and sadness experiences correlated with neural activity in specific brain regions (orbitofrontal cortex and amygdala, respectively). We observed these correlations across diverse instances within each emotion category, as well as across instances from all three categories. Consistent with a psychological construction approach to emotion, the results suggest that neural circuitry realizes more basic processes across discrete emotions. The implicated brain regions regulate the body to deal with the world, producing the affective changes at the core of emotions and many other psychological phenomena.

Neural Evidence that Human Emotions Share Core Affective Properties

PubMed Central

Wilson-Mendenhall, Christine D.; Barrett, Lisa Feldman; Barsalou, Lawrence W.

2014-01-01

Research on the “emotional brain” remains centered around the idea that emotions like fear, happiness, and sadness result from specialized and distinct neural circuitry. Accumulating behavioral and physiological evidence suggests, instead, that emotions are grounded in core affect – a person's fluctuating level of pleasant or unpleasant arousal. A neuroimaging study revealed that participants' subjective ratings of valence (i.e., pleasure/displeasure) and of arousal evoked by various fear, happiness, and sadness experiences correlated with neural activity in specific brain regions (orbitofrontal cortex and amygdala, respectively). We observed these correlations across diverse instances within each emotion category, as well as across instances from all three categories. Consistent with a psychological construction approach to emotion, the results suggest that neural circuitry realizes more basic processes across discrete emotions. The implicated brain regions regulate the body to deal with the world, producing the affective changes at the core of emotions and many other psychological phenomena. PMID:23603916

Successful Implementation of Inquiry-Based Physiology Laboratories in Undergraduate Major and Nonmajor Courses

ERIC Educational Resources Information Center

Casotti, G.; Rieser-Danner, L.; Knabb, M. T.

2008-01-01

Recent evidence has demonstrated that inquiry-based physiology laboratories improve students' critical- and analytical-thinking skills. We implemented inquiry-based learning into three physiology courses: Comparative Vertebrate Physiology (majors), Human Physiology (majors), and Human Anatomy and Physiology (nonmajors). The aims of our curricular…

How consumer physical activity monitors could transform human physiology research.

PubMed

Wright, Stephen P; Hall Brown, Tyish S; Collier, Scott R; Sandberg, Kathryn

2017-03-01

A sedentary lifestyle and lack of physical activity are well-established risk factors for chronic disease and adverse health outcomes. Thus, there is enormous interest in measuring physical activity in biomedical research. Many consumer physical activity monitors, including Basis Health Tracker, BodyMedia Fit, DirectLife, Fitbit Flex, Fitbit One, Fitbit Zip, Garmin Vivofit, Jawbone UP, MisFit Shine, Nike FuelBand, Polar Loop, Withings Pulse O 2 , and others have accuracies similar to that of research-grade physical activity monitors for measuring steps. This review focuses on the unprecedented opportunities that consumer physical activity monitors offer for human physiology and pathophysiology research because of their ability to measure activity continuously under real-life conditions and because they are already widely used by consumers. We examine current and potential uses of consumer physical activity monitors as a measuring or monitoring device, or as an intervention in strategies to change behavior and predict health outcomes. The accuracy, reliability, reproducibility, and validity of consumer physical activity monitors are reviewed, as are limitations and challenges associated with using these devices in research. Other topics covered include how smartphone apps and platforms, such as the Apple ResearchKit, can be used in conjunction with consumer physical activity monitors for research. Lastly, the future of consumer physical activity monitors and related technology is considered: pattern recognition, integration of sleep monitors, and other biosensors in combination with new forms of information processing. Copyright © 2017 the American Physiological Society.

A DYNAMIC PHYSIOLOGICALLY-BASED TOXICOKINETIC (DPBTK) MODEL FOR SIMULATION OF COMPLEX TOLUENE EXPOSURE SCENARIOS IN HUMANS

EPA Science Inventory

A GENERAL PHYSIOLOGICAL AND TOXICOKINETIC (GPAT) MODEL FOR SIMULATION OF COMPLEX TOLUENE EXPOSURE SCENARIOS IN HUMANS. E M Kenyon1, T Colemen2, C R Eklund1 and V A Benignus3. 1U.S. EPA, ORD, NHEERL, ETD, PKB, RTP, NC, USA; 2Biological Simulators, Inc., Jackson MS, USA, 3U.S. EP...

Visualization and simulated surgery of the left ventricle in the virtual pathological heart of the Virtual Physiological Human

PubMed Central

McFarlane, N. J. B.; Lin, X.; Zhao, Y.; Clapworthy, G. J.; Dong, F.; Redaelli, A.; Parodi, O.; Testi, D.

2011-01-01

Ischaemic heart failure remains a significant health and economic problem worldwide. This paper presents a user-friendly software system that will form a part of the virtual pathological heart of the Virtual Physiological Human (VPH2) project, currently being developed under the European Commission Virtual Physiological Human (VPH) programme. VPH2 is an integrated medicine project, which will create a suite of modelling, simulation and visualization tools for patient-specific prediction and planning in cases of post-ischaemic left ventricular dysfunction. The work presented here describes a three-dimensional interactive visualization for simulating left ventricle restoration surgery, comprising the operations of cutting, stitching and patching, and for simulating the elastic deformation of the ventricle to its post-operative shape. This will supply the quantitative measurements required for the post-operative prediction tools being developed in parallel in the same project. PMID:22670207

Nociception from blood vessels is independent of the sympathetic nervous system under physiological conditions in humans.

PubMed

Kindgen-Milles, D; Holthusen, H

1997-06-05

To test the hypothesis that vascular pain depends on sympathetic drive under physiological conditions we studied the effects of both alpha-adrenoceptor stimulation by noradrenaline and alpha-adrenoceptor blockade by phentolamine on the intensity of physicochemically evoked pain from veins in humans. In seven healthy volunteers, a vascularly isolated hand vein segment was perfused continuously with noradrenaline (6 x 10(-9)-6 x 10(-6) M), or phentolamine (1.24 x 10(-4) M). Pain was evoked by intraluminal electrostimulation or by injection of hyperosmolar saline during control perfusion of isoosmolar saline and after each noradrenaline concentration, as well as after perfusion of phentolamine. Subjects rated pain intensity continuously on an electronically controlled visual analogue scale (VAS) between 0% VAS (no pain) and 100% VAS (tolerance maximum). Intravenous electrostimulation as well as hyperosmolar solutions evoked pain in each subject. The intensity of pain was neither influenced by noradrenaline, nor by phentolamine, so that nociception from blood vessels is unlikely to be modulated by the sympathetic nervous system under physiological conditions in humans.

Measurements, modeling, control and simulation - as applied to the human left ventricle for purposeful physiological monitoring.

NASA Technical Reports Server (NTRS)

Ghista, D. N.; Rasmussen, D. N.; Linebarger, R. N.; Sandler, H.

1971-01-01

Interdisciplinary engineering research effort in studying the intact human left ventricle has been employed to physiologically monitor the heart and to obtain its 'state-of-health' characteristics. The left ventricle was selected for this purpose because it plays a key role in supplying energy to the body cells. The techniques for measurement of the left ventricular geometry are described; the geometry is effectively displayed to bring out the abnormalities in cardiac function. Methods of mathematical modeling, which make it possible to determine the performance of the intact left ventricular muscle, are also described. Finally, features of a control system for the left ventricle for predicting the effect of certain physiological stress situations on the ventricle performance are discussed.

Improving the physiological realism of experimental models

PubMed Central

Vinnakota, Kalyan C.; Cha, Chae Y.; Rorsman, Patrik; Balaban, Robert S.; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A.

2016-01-01

The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease. PMID:27051507

Physiological and affective reactivity to a 35% CO₂ inhalation challenge in individuals differing in the 5-HTTLPR genotype and trait neuroticism.

PubMed

Verschoor, Ellen; Markus, C Rob

2012-08-01

The inhalation of 35% carbon dioxide (CO₂) results in an acute stress response in healthy individuals and may accordingly provide a good paradigm to examine potential vulnerability factors for stress reactivity and stress-related psychopathology. It has been proposed that CO₂ reactivity is moderated by genetic (5-HTTLPR) and personality (neuroticism) factors, yet no experimental study has investigated their effects on CO₂ reactivity simultaneously. The current study examined the singular and interactive effects of the 5-HTTLPR genotype and neuroticism in predicting the affective and physiological response to a 35% CO₂ challenge in a healthy sample of male and female students. From a large group of 771 students, 48 carriers of the low/low expressing allele (S/S, S/Lg, Lg/Lg) and 48 carriers of the high/high expressing allele (La/La) with the lowest and the highest neuroticism scores (77 females, 19 males; mean age ± SD: 20.6 ± 2 years) were selected and underwent a 35% CO₂ inhalation. Visual analogue scales for anxiety and discomfort and the Panic Symptom List were used to assess affective symptomatology, while salivary samples and heart rate were assessed to establish the physiological response. A typical pattern of responses to CO₂ was observed, characterised by increases in anxiogenic symptoms and physical panic symptomatology and a reduction in heart rate; however, no effect on salivary cortisol concentration was observed. Additionally, the CO₂ reactivity did not differ between groups divided by the 5-HTTLPR genotype or neuroticism. Findings of the current study do not support a role for singular or interactive effects of the 5-HTTLPR genotype and trait neuroticism on affective and physiological reactivity to a 35% CO₂ inhalation procedure. Copyright © 2011 Elsevier B.V. and ECNP. All rights reserved.

Macromolecular crowding meets oxygen tension in human mesenchymal stem cell culture - A step closer to physiologically relevant in vitro organogenesis

NASA Astrophysics Data System (ADS)

Cigognini, Daniela; Gaspar, Diana; Kumar, Pramod; Satyam, Abhigyan; Alagesan, Senthilkumar; Sanz-Nogués, Clara; Griffin, Matthew; O'Brien, Timothy; Pandit, Abhay; Zeugolis, Dimitrios I.

2016-08-01

Modular tissue engineering is based on the cells’ innate ability to create bottom-up supramolecular assemblies with efficiency and efficacy still unmatched by man-made devices. Although the regenerative potential of such tissue substitutes has been documented in preclinical and clinical setting, the prolonged culture time required to develop an implantable device is associated with phenotypic drift and/or cell senescence. Herein, we demonstrate that macromolecular crowding significantly enhances extracellular matrix deposition in human bone marrow mesenchymal stem cell culture at both 20% and 2% oxygen tension. Although hypoxia inducible factor - 1α was activated at 2% oxygen tension, increased extracellular matrix synthesis was not observed. The expression of surface markers and transcription factors was not affected as a function of oxygen tension and macromolecular crowding. The multilineage potential was also maintained, albeit adipogenic differentiation was significantly reduced in low oxygen tension cultures, chondrogenic differentiation was significantly increased in macromolecularly crowded cultures and osteogenic differentiation was not affected as a function of oxygen tension and macromolecular crowding. Collectively, these data pave the way for the development of bottom-up tissue equivalents based on physiologically relevant developmental processes.

Macromolecular crowding meets oxygen tension in human mesenchymal stem cell culture - A step closer to physiologically relevant in vitro organogenesis

PubMed Central

Cigognini, Daniela; Gaspar, Diana; Kumar, Pramod; Satyam, Abhigyan; Alagesan, Senthilkumar; Sanz-Nogués, Clara; Griffin, Matthew; O’Brien, Timothy; Pandit, Abhay; Zeugolis, Dimitrios I.

2016-01-01

Modular tissue engineering is based on the cells’ innate ability to create bottom-up supramolecular assemblies with efficiency and efficacy still unmatched by man-made devices. Although the regenerative potential of such tissue substitutes has been documented in preclinical and clinical setting, the prolonged culture time required to develop an implantable device is associated with phenotypic drift and/or cell senescence. Herein, we demonstrate that macromolecular crowding significantly enhances extracellular matrix deposition in human bone marrow mesenchymal stem cell culture at both 20% and 2% oxygen tension. Although hypoxia inducible factor - 1α was activated at 2% oxygen tension, increased extracellular matrix synthesis was not observed. The expression of surface markers and transcription factors was not affected as a function of oxygen tension and macromolecular crowding. The multilineage potential was also maintained, albeit adipogenic differentiation was significantly reduced in low oxygen tension cultures, chondrogenic differentiation was significantly increased in macromolecularly crowded cultures and osteogenic differentiation was not affected as a function of oxygen tension and macromolecular crowding. Collectively, these data pave the way for the development of bottom-up tissue equivalents based on physiologically relevant developmental processes. PMID:27478033

Role of the liver X receptors in skin physiology: Putative pharmacological targets in human diseases.

PubMed

Ouedraogo, Zangbéwendé Guy; Fouache, Allan; Trousson, Amalia; Baron, Silvère; Lobaccaro, Jean-Marc A

2017-10-01

Liver X receptors (LXRs) are members of the nuclear receptor superfamily that have been shown to regulate various physiological functions such as lipid metabolism and cholesterol homeostasis. Concordant reports have elicited the possibility to target them to cure many human diseases including arteriosclerosis, cancer, arthritis, and diabetes. The high relevance of modulating LXR activities to treat numerous skin diseases, mainly those with exacerbated inflammation processes, contrasts with the lack of approved therapeutic use. This review makes an assessment to sum up the findings regarding the physiological roles of LXRs in skin and help progress towards the therapeutic and safe management of their activities. It focuses on the possible pharmacological targeting of LXRs to cure or prevent selected skin diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Human Empathy, Personality and Experience Affect the Emotion Ratings of Dog and Human Facial Expressions.

PubMed

Kujala, Miiamaaria V; Somppi, Sanni; Jokela, Markus; Vainio, Outi; Parkkonen, Lauri

2017-01-01

Facial expressions are important for humans in communicating emotions to the conspecifics and enhancing interpersonal understanding. Many muscles producing facial expressions in humans are also found in domestic dogs, but little is known about how humans perceive dog facial expressions, and which psychological factors influence people's perceptions. Here, we asked 34 observers to rate the valence, arousal, and the six basic emotions (happiness, sadness, surprise, disgust, fear, and anger/aggressiveness) from images of human and dog faces with Pleasant, Neutral and Threatening expressions. We investigated how the subjects' personality (the Big Five Inventory), empathy (Interpersonal Reactivity Index) and experience of dog behavior affect the ratings of dog and human faces. Ratings of both species followed similar general patterns: human subjects classified dog facial expressions from pleasant to threatening very similarly to human facial expressions. Subjects with higher emotional empathy evaluated Threatening faces of both species as more negative in valence and higher in anger/aggressiveness. More empathetic subjects also rated the happiness of Pleasant humans but not dogs higher, and they were quicker in their valence judgments of Pleasant human, Threatening human and Threatening dog faces. Experience with dogs correlated positively with ratings of Pleasant and Neutral dog faces. Personality also had a minor effect on the ratings of Pleasant and Neutral faces in both species. The results imply that humans perceive human and dog facial expression in a similar manner, and the perception of both species is influenced by psychological factors of the evaluators. Especially empathy affects both the speed and intensity of rating dogs' emotional facial expressions.

Human Empathy, Personality and Experience Affect the Emotion Ratings of Dog and Human Facial Expressions

PubMed Central

Kujala, Miiamaaria V.; Somppi, Sanni; Jokela, Markus; Vainio, Outi; Parkkonen, Lauri

2017-01-01

Facial expressions are important for humans in communicating emotions to the conspecifics and enhancing interpersonal understanding. Many muscles producing facial expressions in humans are also found in domestic dogs, but little is known about how humans perceive dog facial expressions, and which psychological factors influence people’s perceptions. Here, we asked 34 observers to rate the valence, arousal, and the six basic emotions (happiness, sadness, surprise, disgust, fear, and anger/aggressiveness) from images of human and dog faces with Pleasant, Neutral and Threatening expressions. We investigated how the subjects’ personality (the Big Five Inventory), empathy (Interpersonal Reactivity Index) and experience of dog behavior affect the ratings of dog and human faces. Ratings of both species followed similar general patterns: human subjects classified dog facial expressions from pleasant to threatening very similarly to human facial expressions. Subjects with higher emotional empathy evaluated Threatening faces of both species as more negative in valence and higher in anger/aggressiveness. More empathetic subjects also rated the happiness of Pleasant humans but not dogs higher, and they were quicker in their valence judgments of Pleasant human, Threatening human and Threatening dog faces. Experience with dogs correlated positively with ratings of Pleasant and Neutral dog faces. Personality also had a minor effect on the ratings of Pleasant and Neutral faces in both species. The results imply that humans perceive human and dog facial expression in a similar manner, and the perception of both species is influenced by psychological factors of the evaluators. Especially empathy affects both the speed and intensity of rating dogs’ emotional facial expressions. PMID:28114335

Artificial light at night advances avian reproductive physiology

PubMed Central

Dominoni, Davide; Quetting, Michael; Partecke, Jesko

2013-01-01

Artificial light at night is a rapidly increasing phenomenon and it is presumed to have global implications. Light at night has been associated with health problems in humans as a consequence of altered biological rhythms. Effects on wild animals have been less investigated, but light at night has often been assumed to affect seasonal cycles of urban dwellers. Using light loggers attached to free-living European blackbirds (Turdus merula), we first measured light intensity at night which forest and city birds are subjected to in the wild. Then we used these measurements to test for the effect of light at night on timing of reproductive physiology. Captive city and forest blackbirds were exposed to either dark nights or very low light intensities at night (0.3 lux). Birds exposed to light at night developed their reproductive system up to one month earlier, and also moulted earlier, than birds kept under dark nights. Furthermore, city birds responded differently than forest individuals to the light at night treatment, suggesting that urbanization can alter the physiological phenotype of songbirds. Our results emphasize the impact of human-induced lighting on the ecology of millions of animals living in cities and call for an understanding of the fitness consequences of light pollution. PMID:23407836

Gastrointestinal Physiology During Head Down Tilt Bedrest in Human Subjects

NASA Technical Reports Server (NTRS)

Vaksman, Z.; Guthienz, J.; Putcha, L.

2008-01-01

Introduction: Gastrointestinal (GI) motility plays a key role in the physiology and function of the GI tract. It directly affects absorption of medications and nutrients taken by mouth, in addition to indirectly altering GI physiology by way of changes in the microfloral composition and biochemistry of the GI tract. Astronauts have reported nausea, loss of appetite and constipation during space flight all of which indicate a reduction in GI motility and function similar to the one seen in chronic bed rest patients. The purpose of this study is to determine GI motility and bacterial proliferation during -6 degree head down tilt bed rest (HTD). Methods: Healthy male and female subjects between the ages of 25-40 participated in a 60 day HTD study protocol. GI transit time (GITT) was determined using lactulose breath hydrogen test and bacterial overgrowth was measured using glucose breath hydrogen test. H. Pylori colonization was determined using C13-urea breath test (UBIT#). All three tests were conducted on 9 days before HDT, and repeated on HDT days 2, 28, 58, and again on day 7 after HDT. Results: GITT increased during HTD compared to the respective ambulatory control values; GITT was significantly lower on day 7 after HTD. A concomitant increase in bacterial colonization was also noticed during HDT starting after approximately 28 days of HDT. However, H. Pylori proliferation was not recorded during HDT as indicated by UBIT#. Conclusion: GITT significantly decreased during HDT with a concomitant increase in the proliferation of GI bacterial flora but not H. pylori.

Skin Blood Perfusion and Oxygenation Colour Affect Perceived Human Health

PubMed Central

Stephen, Ian D.; Coetzee, Vinet; Law Smith, Miriam; Perrett, David I.

2009-01-01

Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice. PMID:19337378

Skin blood perfusion and oxygenation colour affect perceived human health.

PubMed

Stephen, Ian D; Coetzee, Vinet; Law Smith, Miriam; Perrett, David I

2009-01-01

Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice.

Repeated pulse exposures to lambda-cyhalothrin affect the behavior, physiology, and survival of the damselfly larvae Ischnura graellsii (Insecta; Odonata).

PubMed

Finotello, Simone; Feckler, Alexander; Bundschuh, Mirco; Johansson, Frank

2017-10-01

Damselflies form an essential part of the aquatic and terrestrial food web. Pesticides may, however, negatively affect their behavior, physiology, and survival. To assess this, a 42-day-lasting bioassay was conducted, during which damselfly larvae (Ischnura graellsii; n = 20) were repeatedly exposed to lambda-cyhalothrin (3 days at; 0, 10, 50, 250, 1250, and 6250ng LCH L -1 ), followed by recovery phases (4 days) in pesticide-free medium for six weeks. This exposure design was used to simulate frequent runoff events in the field. Variables related to the behavior (strikes against prey and capture success), growth, physiology (lipid content and fatty acid composition), as well as mortality were assessed throughout the experiment. The two highest LCH concentrations induced 100% mortality within the first 48h, whereas 85% of the test organisms survived 28 days under control conditions. The number of strikes against prey was not affected by LCH. In contrast, prey capture success decreased significantly (up to ~50% at 250ng LCH L -1 , for instance, after the third pulse exposure) following LCH-exposures compared to the control. This difference was not observed after recovery phases, however, which did not counteract the enhanced energy demand for detoxification and defense mechanisms indicated by a lower growth rate (up to ~20%) and lipid content (up to ~30%) of damselflies at 50 and 250ng LCH L -1 . In addition, two essential fatty acids (eicosapentaenoic acid and arachidonic acid) and two precursors (linolenic acid and α-linolenic acid) decreased in their concentrations upon exposure towards 250ng LCH L -1 . Thus the results of this study indicate that long-term exposure towards LCH pulses can affect damselfly behavior, physiology and survival. Given the essential role of damselflies in food web dynamics, these effects may potentially translate into local population impairments with subsequent bottom-up directed effects within and across ecosystem boundaries

Ex vivo isolation protocols differentially affect the phenotype of human CD4+ T cells.

PubMed

Bernard, Frédéric; Jaleco, Sara; Dardalhon, Valérie; Steinberg, Marcos; Yssel, Hans; Noraz, Nelly; Taylor, Naomi; Kinet, Sandrina

2002-12-20

Leukemic T cell lines have facilitated signal transduction studies but their physiological relevance is restricted. The use of primary T lymphocytes overcomes this limitation but it has long been speculated that methodological aspects of blood collection and the isolation procedure modify the phenotype of the cell. Here we demonstrate that several characteristics of human peripheral T cells are affected by the selection conditions. A significantly higher induction of the chemokine receptor CXCR4 was observed on CD4+ lymphocytes isolated by sheep red blood cell (SRBC) rosetting and CD4 MicroBeads as compared with positively selected CD4+ cells where the antibody/bead complex was immediately detached. These latter cells expressed CXCR4 at levels equivalent to that observed on CD4+ lymphocytes obtained by negative antibody-mediated selection. Furthermore, CD4+ cells isolated by SRBC rosetting and CD4 MicroBeads formed aggregates upon in vitro culture. CD4+ lymphocytes obtained by SRBC rosetting as well as those isolated following positive selection demonstrated basal phosphorylation of the extracellular signal-regulated kinase (ERK)-2. Altogether these data suggest that certain discrepancies concerning signal transduction in primary human T cells can be attributed to the selection conditions. Thus, it is essential to establish the parameters influenced by the isolation protocol in order to fully interpret T cell responses to antigens, chemokines, and cytokines.

Can modular psychological concepts like affect and emotion be assigned to a distinct subset of regional neural circuits?. Comment on "The quartet theory of human emotions: An integrative and neurofunctional model" by S. Koelsch et al.

NASA Astrophysics Data System (ADS)

Fehr, Thorsten; Herrmann, Manfred

2015-06-01

The proposed Quartet Theory of Human Emotions by Koelsch and co-workers [11] adumbrates evidence from various scientific sources to integrate and assign the psychological concepts of 'affect' and 'emotion' to four brain circuits or to four neuronal core systems for affect-processing in the brain. The authors differentiate between affect and emotion and assign several facultative, or to say modular, psychological domains and principles of information processing, such as learning and memory, antecedents of affective activity, emotion satiation, cognitive complexity, subjective quality feelings, degree of conscious appraisal, to different affect systems. Furthermore, they relate orbito-frontal brain structures to moral affects as uniquely human, and the hippocampus to attachment-related affects. An additional feature of the theory describes 'emotional effector-systems' for motor-related processes (e.g., emotion-related actions), physiological arousal, attention and memory that are assumed to be cross-linked with the four proposed affect systems. Thus, higher principles of emotional information processing, but also modular affect-related issues, such as moral and attachment related affects, are thought to be handled by these four different physiological sub-systems that are on the other side assumed to be highly interwoven at both physiological and functional levels. The authors also state that the proposed sub-systems have many features in common, such as the selection and modulation of biological processes related to behaviour, perception, attention and memory. The latter aspect challenges an ongoing discussion about the mind-body problem: To which degree do the proposed sub-systems 'sufficiently' cover the processing of complex modular or facultative emotional/affective and/or cognitive phenomena? There are current models and scientific positions that almost completely reject the idea that modular psychological phenomena are handled by a distinct selection of

Physiology, behavior, and conservation.

PubMed

Cooke, Steven J; Blumstein, Daniel T; Buchholz, Richard; Caro, Tim; Fernández-Juricic, Esteban; Franklin, Craig E; Metcalfe, Julian; O'Connor, Constance M; St Clair, Colleen Cassady; Sutherland, William J; Wikelski, Martin

2014-01-01

Many animal populations are in decline as a result of human activity. Conservation practitioners are attempting to prevent further declines and loss of biodiversity as well as to facilitate recovery of endangered species, and they often rely on interdisciplinary approaches to generate conservation solutions. Two recent interfaces in conservation science involve animal behavior (i.e., conservation behavior) and physiology (i.e., conservation physiology). To date, these interfaces have been considered separate entities, but from both pragmatic and biological perspectives, there is merit in better integrating behavior and physiology to address applied conservation problems and to inform resource management. Although there are some institutional, conceptual, methodological, and communication-oriented challenges to integrating behavior and physiology to inform conservation actions, most of these barriers can be overcome. Through outlining several successful examples that integrate these disciplines, we conclude that physiology and behavior can together generate meaningful data to support animal conservation and management actions. Tangentially, applied conservation and management problems can, in turn, also help advance and reinvigorate the fundamental disciplines of animal physiology and behavior by providing advanced natural experiments that challenge traditional frameworks.

Human organoid cultures: transformative new tools for human virus studies.

PubMed

Ramani, Sasirekha; Crawford, Sue E; Blutt, Sarah E; Estes, Mary K

2018-04-01

Studies of human infectious diseases have been limited by the paucity of functional models that mimic normal human physiology and pathophysiology. Recent advances in the development of multicellular, physiologically active organotypic cultures produced from embryonic and pluripotent stem cells, as well as from stem cells isolated from biopsies and surgical specimens are allowing unprecedented new studies and discoveries about host-microbe interactions. Here, we summarize recent developments in the use of organoids for studying human viral pathogens, including intestinal infections with human rotavirus, norovirus, enteroviruses and adenoviruses (intestinal organoids and enteroids), neuronal infections with Zika virus (cerebral organoids) and respiratory infections with respiratory syncytial virus in (lung bud organoids). Biologic discovery of host-specific genetic and epigenetic factors affecting infection, and responses to infection that lead to disease are possible with the use of organoid cultures. Continued development to increase the complexity of these cultures by including components of the normal host tissue microenvironment such as immune cells, blood vessels and microbiome, will facilitate studies on human viral pathogenesis, and advance the development of platforms for pre-clinical evaluation of vaccines, antivirals and therapeutics. Copyright © 2018 Elsevier B.V. All rights reserved.

Selective attention reduces physiological noise in the external ear canals of humans. II: Visual attention

PubMed Central

Walsh, Kyle P.; Pasanen, Edward G.; McFadden, Dennis

2014-01-01

Human subjects performed in several behavioral conditions requiring, or not requiring, selective attention to visual stimuli. Specifically, the attentional task was to recognize strings of digits that had been presented visually. A nonlinear version of the stimulus-frequency otoacoustic emission (SFOAE), called the nSFOAE, was collected during the visual presentation of the digits. The segment of the physiological response discussed here occurred during brief silent periods immediately following the SFOAE-evoking stimuli. For all subjects tested, the physiological-noise magnitudes were substantially weaker (less noisy) during the tasks requiring the most visual attention. Effect sizes for the differences were >2.0. Our interpretation is that cortico-olivo influences adjusted the magnitude of efferent activation during the SFOAE-evoking stimulation depending upon the attention task in effect, and then that magnitude of efferent activation persisted throughout the silent period where it also modulated the physiological noise present. Because the results were highly similar to those obtained when the behavioral conditions involved auditory attention, similar mechanisms appear to operate both across modalities and within modalities. Supplementary measurements revealed that the efferent activation was spectrally global, as it was for auditory attention. PMID:24732070

Perioperative abstinence from cigarettes: physiologic and clinical consequences.

PubMed

Warner, David O

2006-02-01

Chronic exposure to cigarette smoke produces profound changes in physiology that may alter responses to perioperative interventions and contribute to perioperative morbidity. Because of smoke-free policies in healthcare facilities, all smokers undergoing surgery are abstinent from cigarettes for at least some period of time so that all are in various stages of recovery from the effects of smoke. Understanding this recovery process will help perioperative physicians better treat these patients. This review examines current knowledge regarding how both short-term (duration ranging from hours to weeks) and long-term smoking cessation affects selected physiology and pathophysiology of particular relevance to perioperative outcomes and how these changes affect perioperative risk. It will also consider current evidence regarding how nicotine replacement therapy, a valuable adjunct to help patients maintain abstinence, may affect perioperative physiology.

Molecular crowding favors reactivity of a human ribozyme under physiological ionic conditions.

PubMed

Strulson, Christopher A; Yennawar, Neela H; Rambo, Robert P; Bevilacqua, Philip C

2013-11-19

In an effort to relate RNA folding to function under cellular-like conditions, we monitored the self-cleavage reaction of the human hepatitis delta virus-like CPEB3 ribozyme in the background of physiological ionic concentrations and various crowding and cosolute agents. We found that at physiological free Mg(2+) concentrations (∼0.1-0.5 mM), both crowders and cosolutes stimulate the rate of self-cleavage, up to ∼6-fold, but that in 10 mM Mg(2+) (conditions widely used for in vitro ribozyme studies) these same additives have virtually no effect on the self-cleavage rate. We further observe a dependence of the self-cleavage rate on crowder size, wherein the level of rate stimulation is diminished for crowders larger than the size of the unfolded RNA. Monitoring effects of crowding and cosolute agents on rates in biological amounts of urea revealed additive-promoted increases at both low and high Mg(2+) concentrations, with a maximal stimulation of more than 10-fold and a rescue of the rate to its urea-free values. Small-angle X-ray scattering experiments reveal a structural basis for this stimulation in that higher-molecular weight crowding agents favor a more compact form of the ribozyme in 0.5 mM Mg(2+) that is essentially equivalent to the form under standard ribozyme conditions of 10 mM Mg(2+) without a crowder. This finding suggests that at least a portion of the rate enhancement arises from favoring the native RNA tertiary structure. We conclude that cellular-like crowding supports ribozyme reactivity by favoring a compact form of the ribozyme, but only under physiological ionic and cosolute conditions.

Physiological, Pharmacological, and Nutritional Regulation of Circulating Adiponectin Concentrations in Humans

PubMed Central

Swarbrick, Michael M.

2008-01-01

Abstract Adiponectin is an adipocyte hormone that links visceral adiposity with insulin resistance and atherosclerosis. It is unique among adipocyte-derived hormones in that its circulating concentrations are inversely proportional to adiposity, and low adiponectin concentrations predict the development of type 2 diabetes and cardiovascular disease. Consequently, in the decade since its discovery, adiponectin has generated immense interest as a potential therapeutic target for the metabolic syndrome and diabetes. This review summarizes current research regarding the regulation of circulating adiponectin concentrations by physiological, pharmacological, and nutritional factors, with an emphasis on human studies. In humans, plasma adiponectin concentrations are influenced by age and gender, and are inversely proportional to visceral adiposity. In vitro studies suggest that adiponectin production may be determined primarily by adipocyte size and insulin sensitivity, with larger, insulin-resistant adipocytes producing less adiponectin. While adiponectin concentrations are unchanged after meal ingestion, they are increased by significant weight loss, such as after bariatric surgery. In addition, adiponectin production is inhibited by a number of hormones, including testosterone, prolactin, glucocorticoids and growth hormone, and by inflammation and oxidative stress in adipose tissue. Smoking decreases, while moderate alcohol consumption increases, circulating adiponectin concentrations. Dietary fatty acid composition in rodents influences adiponectin production via ligand-activated nuclear receptors (PPARs); however, current evidence in humans is equivocal. In addition to PPAR agonists (such as thiazolidinediones and fibrates), a number of pharmacological agents (angiotensin receptor type 1 blockers, ACE inhibitors, and cannabinoid receptor antagonists) used in treatment of the metabolic syndrome also increase adiponectin concentrations in humans. PMID:18510434

Physiological Responses to Thermal Stress and Exercise

NASA Astrophysics Data System (ADS)

Iyota, Hiroyuki; Ohya, Akira; Yamagata, Junko; Suzuki, Takashi; Miyagawa, Toshiaki; Kawabata, Takashi

The simple and noninvasive measuring methods of bioinstrumentation in humans is required for optimization of air conditioning and management of thermal environments, taking into consideration the individual specificity of the human body as well as the stress conditions affecting each. Changes in human blood circulation were induced with environmental factors such as heat, cold, exercise, mental stress, and so on. In this study, the physiological responses of human body to heat stress and exercise were investigated in the initial phase of the developmental research. We measured the body core and skin temperatures, skin blood flow, and pulse wave as the indices of the adaptation of the cardiovascular system. A laser Doppler skin blood flowmetry using an optical-sensor with a small portable data logger was employed for the measurement. These results reveal the heat-stress and exercise-induced circulatory responses, which are under the control of the sympathetic nerve system. Furthermore, it was suggested that the activity of the sympathetic nervous system could be evaluated from the signals of the pulse wave included in the signals derived from skin blood flow by means of heart rate variability assessments and detecting peak heights of velocity-plethysmogram.

The effects of gender on circadian rhythm of human physiological indexes in high temperature environment

NASA Astrophysics Data System (ADS)

Zheng, G. Z.; Li, K.; Bu, W. T.; Lu, Y. Z.; Wang, Y. J.

2018-03-01

In the context of frequent high temperature weather in recent years, peoples’ physical health is seriously threatened by the indoor high temperature. The physiological activities of human body show a certain changes of circadian rhythm. In this paper, the circadian rhythms of the physiological indexes in indoor high temperature environment were quantified and compared between the male subjects and female subjects. Ten subjects (five males and five females) were selected. The temperature conditions were set at 28°C, 32°C, 36°C and 38°C, respectively. The blood pressure, heart rate, rectal temperature, eardrum temperature, forehead temperature and mean skin temperature were measured for 24 hours continuously. The medians, amplitudes and acrophases of the circadian rhythms were obtained by the cosinor analysis method. Then the effects of gender on the circadian rhythm of the human body in high temperature environment were analyzed. The results indicate that, compared with the female subjects, the male medians of the systolic pressure and diastolic pressure were higher, and the male medians of heart rate and rectal temperature were lower, however, no significant differences were found between eardrum temperature, forehead temperature and mean skin temperature. This study can provide scientific basis for the health protection of the indoor relevant personnel.

Altered physiological functions and ion currents in atrial fibroblasts from patients with chronic atrial fibrillation.

PubMed

Poulet, Claire; Künzel, Stephan; Büttner, Edgar; Lindner, Diana; Westermann, Dirk; Ravens, Ursula

2016-02-01

The contribution of human atrial fibroblasts to cardiac physiology and pathophysiology is poorly understood. Fibroblasts may contribute to arrhythmogenesis through fibrosis, or by directly altering electrical activity in cardiomyocytes. The objective of our study was to uncover phenotypic differences between cells from patients in sinus rhythm (SR) and chronic atrial fibrillation (AF), with special emphasis on electrophysiological properties. We isolated fibroblasts from human right atrial tissue for patch-clamp experiments, proliferation, migration, and differentiation assays, and gene expression profiling. In culture, proliferation and migration of AF fibroblasts were strongly impaired but differentiation into myofibroblasts was increased. This was associated with a higher number of AF fibroblasts expressing functional Nav1.5 channels. Strikingly Na(+) currents were considerably larger in AF cells. Blocking Na(+) channels in culture with tetrodotoxin did not affect proliferation, migration, or differentiation in neither SR nor AF cells. While freshly isolated fibroblasts showed mostly weak rectifier currents, fibroblasts in culture developed outward rectifier K(+) currents of similar amplitude between the SR and AF groups. Adding the K(+) channel blockers tetraethylammonium and 4-aminopyridin in culture reduced current amplitude and inhibited proliferation in the SR group only. Analysis of gene expression revealed significant differences between SR and AF in genes encoding for ion channels, collagen, growth factors, connexins, and cadherins. In conclusion, this study shows that under AF conditions atrial fibroblasts undergo phenotypic changes that are revealed in culture. Future experiments should be performed in situ to understand the nature of those changes and whether they affect cardiac electrical activity. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological

Physiologic Basis for Understanding Quantitative Dehydration Assessment

DTIC Science & Technology

2012-01-01

Perspective Physiologic basis for understanding quantitative dehydration assessment1–4 Samuel N Cheuvront, Robert W Kenefick, Nisha Charkoudian, and...Michael N Sawka ABSTRACT Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance...review the physiologic basis for understanding quantitative dehydration as- sessment. We highlight how phenomenologic interpretations of de- hydration

High-throughput identification of small molecules that affect human embryonic vascular development

PubMed Central

Vazão, Helena; Rosa, Susana; Barata, Tânia; Costa, Ricardo; Pitrez, Patrícia R.; Honório, Inês; de Vries, Margreet R.; Papatsenko, Dimitri; Benedito, Rui; Saris, Daniel; Khademhosseini, Ali; Quax, Paul H. A.; Pereira, Carlos F.; Mercader, Nadia; Ferreira, Lino

2017-01-01

Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and limited mechanistic information regarding the biological pathways and potential adverse consequences in humans. To develop a screening platform for molecules that affect human embryonic development based on endothelial cells (ECs) derived from human pluripotent stem cells, we differentiated human pluripotent stem cells into embryonic ECs and induced their maturation under arterial flow conditions. These cells were then used to screen compounds that specifically affect embryonic vasculature. Using this platform, we have identified two compounds that have higher inhibitory effect in embryonic than postnatal ECs. One of them was fluphenazine (an antipsychotic), which inhibits calmodulin kinase II. The other compound was pyrrolopyrimidine (an antiinflammatory agent), which inhibits vascular endothelial growth factor receptor 2 (VEGFR2), decreases EC viability, induces an inflammatory response, and disrupts preformed vascular networks. The vascular effect of the pyrrolopyrimidine was further validated in prenatal vs. adult mouse ECs and in embryonic and adult zebrafish. We developed a platform based on human pluripotent stem cell-derived ECs for drug screening, which may open new avenues of research for the study and modulation of embryonic vasculature. PMID:28348206

High-throughput identification of small molecules that affect human embryonic vascular development.

PubMed

Vazão, Helena; Rosa, Susana; Barata, Tânia; Costa, Ricardo; Pitrez, Patrícia R; Honório, Inês; de Vries, Margreet R; Papatsenko, Dimitri; Benedito, Rui; Saris, Daniel; Khademhosseini, Ali; Quax, Paul H A; Pereira, Carlos F; Mercader, Nadia; Fernandes, Hugo; Ferreira, Lino

2017-04-11

Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and limited mechanistic information regarding the biological pathways and potential adverse consequences in humans. To develop a screening platform for molecules that affect human embryonic development based on endothelial cells (ECs) derived from human pluripotent stem cells, we differentiated human pluripotent stem cells into embryonic ECs and induced their maturation under arterial flow conditions. These cells were then used to screen compounds that specifically affect embryonic vasculature. Using this platform, we have identified two compounds that have higher inhibitory effect in embryonic than postnatal ECs. One of them was fluphenazine (an antipsychotic), which inhibits calmodulin kinase II. The other compound was pyrrolopyrimidine (an antiinflammatory agent), which inhibits vascular endothelial growth factor receptor 2 (VEGFR2), decreases EC viability, induces an inflammatory response, and disrupts preformed vascular networks. The vascular effect of the pyrrolopyrimidine was further validated in prenatal vs. adult mouse ECs and in embryonic and adult zebrafish. We developed a platform based on human pluripotent stem cell-derived ECs for drug screening, which may open new avenues of research for the study and modulation of embryonic vasculature.

Aberrant patterns of X chromosome inactivation in a new line of human embryonic stem cells established in physiological oxygen concentrations.

PubMed

de Oliveira Georges, Juliana Andrea; Vergani, Naja; Fonseca, Simone Aparecida Siqueira; Fraga, Ana Maria; de Mello, Joana Carvalho Moreira; Albuquerque, Maria Cecília R Maciel; Fujihara, Litsuko Shimabukuro; Pereira, Lygia Veiga

2014-08-01

One of the differences between murine and human embryonic stem cells (ESCs) is the epigenetic state of the X chromosomes in female lines. Murine ESCs (mESCs) present two transcriptionally active Xs that will undergo the dosage compensation process of XCI upon differentiation, whereas most human ESCs (hESCs) spontaneously inactivate one X while keeping their pluripotency. Whether this reflects differences in embryonic development of mice and humans, or distinct culture requirements for the two kinds of pluripotent cells is not known. Recently it has been shown that hESCs established in physiological oxygen levels are in a stable pre-XCI state equivalent to that of mESCs, suggesting that culture in low oxygen concentration is enough to preserve that epigenetic state of the X chromosomes. Here we describe the establishment of two new lines of hESCs under physiological oxygen level and the characterization of the XCI state in the 46,XX line BR-5. We show that a fraction of undifferentiated cells present XIST RNA accumulation and single H3K27me foci, characteristic of the inactive X. Moreover, analysis of allele specific gene expression suggests that pluripotent BR-5 cells present completely skewed XCI. Our data indicate that physiological levels of oxygen are not sufficient for the stabilization of the pre-XCI state in hESCs.

Teaching first-year medical students physiology: does the human patient simulator allow for more effective teaching?

PubMed

Tan, G M; Ti, L K; Suresh, S; Ho, B S; Lee, T L

2002-05-01

Although the Human Patient Simulator (HPS) is an effective teaching tool in many medical fields, literature supporting its use in the teaching of physiology to medical students is lacking. This study investigated the effectiveness of HPS-based teaching of cardiovascular physiology to first-year medical students. Two hundred and ten first-year medical students were scheduled to our HPS laboratory with the purpose of demonstrating "physiology in action". Students were divided into groups of 19-25 each, and attended a lecture followed by a HPS session. Using a theatre-type simulator complete with mannequin, anaesthesia machine and monitors (METI, Sarasota FL), the scenarios of hypovolaemia, sepsis, and cardiac failure were run to demonstrate the physiological changes that occur with changes in preload, afterload, and cardiac contractility. Each student was given a true/false test before, and again after the HPS session, followed by a survey of their learning experience. There was marked improvement in test scores after the HPS session (82.1% vs. 64.6%, P < 0.001). Most of the students felt that HPS was a better teaching tool (94.5%) and raised more questions (76.5%) than lectures. They wanted more topics to be taught this way (96%), as they could apply and re-enforce textbook knowledge, and visualise real-time changes. However, they felt that their experience could have been enhanced with more time and smaller groups. HPS is an excellent teaching tool as it stimulates student curiosity and makes knowledge acquisition and understanding easier. It is highly desirable to be incorporated into the teaching of physiology.

Interactions between Artificial Gravity, Affected Physiological Systems, and Nutrition

NASA Technical Reports Server (NTRS)

Heer, Martina; Baecker, Natalie; Zwart, Sara; Smith, Scott M.

2007-01-01

Malnutrition, either by insufficient supply of some nutrients or by overfeeding has a profound effect on the health of an organism. Therefore, optimal nutrition is mandatory on Earth (1 g), in microgravity and also when applying artificial gravity to the human system. Immobilization like in microgravity or bed rest also has a profound effect on different physiological systems, like body fluid regulation, the cardiovascular, the musculoskeletal, the immunological system and others. Up to now there is no countermeasure available which is effective to counteract cardiovascular deconditioning (rf. Chapter 5) together with maintenance of the musculoskeletal system in a rather short period of time. Gravity seems therefore to be one of the main stimuli to keep these systems and application of certain duration of artificial gravity per day by centrifugation has often been proposed as a very potential countermeasure against the weakening of the physiological systems. Up to now, neither optimal intensity nor optimal length of application of artificial gravity has been studied sufficiently to recommend a certain, effective and efficient protocol. However, as shown in chapter 5 on cardiovascular system, in chapter 6 on the neuromuscular system and chapter 7 (bone and connective system) artificial gravity has a very high potential to counteract any degradation caused by immobilization. But, nutrient supply -which ideally should match the actual needs- will interact with these changes and therefore has also to be taken into account. It is well known that astronauts beside the Skylab missions- were and are still not optimally nourished during their stay in space (Bourland et al. 2000;Heer et al. 1995;Heer et al. 2000b;Smith et al. 1997;Smith & Lane 1999;Smith et al. 2001;Smith et al. 2005). It has also been described anecdotally that astronauts have lower appetites. One possible explanation could be altered taste and smell sensations during space flight, although in some early

How Do Volcanoes Affect Human Life? Integrated Unit.

ERIC Educational Resources Information Center

Dayton, Rebecca; Edwards, Carrie; Sisler, Michelle

This packet contains a unit on teaching about volcanoes. The following question is addressed: How do volcanoes affect human life? The unit covers approximately three weeks of instruction and strives to present volcanoes in an holistic form. The five subject areas of art, language arts, mathematics, science, and social studies are integrated into…

Does human migration affect international trade? A complex-network perspective.

PubMed

Fagiolo, Giorgio; Mastrorillo, Marina

2014-01-01

This paper explores the relationships between international human migration and merchandise trade, using a complex-network approach. We firstly compare the topological structure of worldwide networks of human migration and bilateral trade over the period 1960-2000. Next, we ask whether the position of any pair of countries in the migration network affects their bilateral trade flows. We show that: (i) both weighted and binary versions of the networks of international migration and trade are strongly correlated; (ii) such correlations can be mostly explained by country economic/demographic size and geographical distance; and (iii) pairs of countries that are more central in the international-migration network trade more. Our findings suggest that bilateral trade between any two countries is not only affected by the presence of migrants from either countries but also by their relative embeddedness in the complex web of corridors making up the network of international human migration.

Global transcriptome analysis of eukaryotic genes affected by gromwell extract.

PubMed

Bang, Soohyun; Lee, Dohyun; Kim, Hanhe; Park, Jiyong; Bahn, Yong-Sun

2014-02-01

Gromwell is known to have diverse pharmacological, cosmetic and nutritional benefits for humans. Nevertheless, the biological influence of gromwell extract (GE) on the general physiology of eukaryotic cells remains unknown. In this study a global transcriptome analysis was performed to identify genes affected by the addition of GE with Cryptococcus neoformans as the model system. In response to GE treatment, genes involved in signal transduction were immediately regulated, and the evolutionarily conserved sets of genes involved in the core cellular functions, including DNA replication, RNA transcription/processing and protein translation/processing, were generally up-regulated. In contrast, a number of genes involved in carbohydrate metabolism and transport, inorganic ion transport and metabolism, post-translational modification/protein turnover/chaperone functions and signal transduction were down-regulated. Among the GE-responsive genes that are also evolutionarily conserved in the human genome, the expression patterns of YSA1, TPO2, CFO1 and PZF1 were confirmed by northern blot analysis. Based on the functional characterization of some GE-responsive genes, it was found that GE treatment may promote cellular tolerance against a variety of environmental stresses in eukaryotes. GE treatment affects the expression levels of a significant portion of the Cryptococcus genome, implying that GE significantly affects the general physiology of eukaryotic cells. © 2013 Society of Chemical Industry.

DEVELOPMENT OF A HUMAN PHYSIOLOGICALLY-BASED PHARMACOKINETIC (PBPK) MODEL FOR INORGANIC ARSENIC AND ITS MONO- AND DI-METHYLATED METABOLITES

EPA Science Inventory

A physiologically-based pharmacokinetic (PBPK) model was developed to estimate levels of arsenic and its metabolites in human tissues and urine after oral exposure to either arsenate (As^V) or arsnite (As^III). The model consists of interconnected individual ...

Selective attention reduces physiological noise in the external ear canals of humans. I: Auditory attention

PubMed Central

Walsh, Kyle P.; Pasanen, Edward G.; McFadden, Dennis

2014-01-01

In this study, a nonlinear version of the stimulus-frequency OAE (SFOAE), called the nSFOAE, was used to measure cochlear responses from human subjects while they simultaneously performed behavioral tasks requiring, or not requiring, selective auditory attention. Appended to each stimulus presentation, and included in the calculation of each nSFOAE response, was a 30-ms silent period that was used to estimate the level of the inherent physiological noise in the ear canals of our subjects during each behavioral condition. Physiological-noise magnitudes were higher (noisier) for all subjects in the inattention task, and lower (quieter) in the selective auditory-attention tasks. These noise measures initially were made at the frequency of our nSFOAE probe tone (4.0 kHz), but the same attention effects also were observed across a wide range of frequencies. We attribute the observed differences in physiological-noise magnitudes between the inattention and attention conditions to different levels of efferent activation associated with the differing attentional demands of the behavioral tasks. One hypothesis is that when the attentional demand is relatively great, efferent activation is relatively high, and a decrease in the gain of the cochlear amplifier leads to lower-amplitude cochlear activity, and thus a smaller measure of noise from the ear. PMID:24732069

Physiology of man and animals in the Tenth Five-Year Plan: Proceedings of the Thirteenth Congress of the I. P. Pavlov All-Union Physiological Society

NASA Technical Reports Server (NTRS)

Lange, K. A.

1980-01-01

Research in the field of animal and human physiology is reviewed. The following topics on problems of physiological science and related fields of knowledge are discussed: neurophysiology and higher nervous activity, physiology of sensory systems, physiology of visceral systems, evolutionary and ecological physiology, physiological cybernetics, computer application in physiology, information support of physiological research, history and theory of development of physiology. Also discussed were: artificial intelligence, physiological problems of reflex therapy, correlation of structure and function of the brain, adaptation and activity, microcirculation, and physiological studies in nerve and mental diseases.

Under a neighbour's influence: public information affects stress hormones and behaviour of a songbird

PubMed Central

Cornelius, Jamie M.; Breuner, Creagh W.; Hahn, Thomas P.

2010-01-01

Socially acquired information improves the accuracy and efficiency of environmental assessments and can increase fitness. Public information may be especially useful during unpredictable food conditions, or for species that depend on resources made less predictable by human disturbance. However, the physiological mechanisms by which direct foraging assessments and public information are integrated to affect behaviour remain largely unknown. We tested for potential effects of public information on the behavioural and hormonal response to food reduction by manipulating the social environment of captive red crossbills (Loxia curvirostra). Red crossbills are irruptive migrants that are considered sensitive to changes in food availability and use public information in decision making. Here, we show that public information can attenuate or intensify the release of glucocorticoids (i.e. stress hormones) during food shortage in red crossbills. The observed modulation of corticosterone may therefore be a physiological mechanism linking public information, direct environmental assessments and behavioural change. This mechanism would not only allow for public information to affect individual behaviour, but might also facilitate group decision making by bringing group members into more similar physiological states. The results further suggest that stressors affecting entire populations may be magnified in individual physiology through social interactions. PMID:20356895

Active Learning and Flipped Classroom, Hand in Hand Approach to Improve Students Learning in Human Anatomy and Physiology

ERIC Educational Resources Information Center

Entezari, Maria; Javdan, Mohammad

2016-01-01

Because Human Anatomy and Physiology (A&P), a gateway course for allied health majors, has high dropout rates nationally, it is challenging to find a successful pedagogical intervention. Reports on the effect of integration of flipped classrooms and whether it improves learning are contradictory for different disciplines. Thus many educators…

21 CFR 882.1835 - Physiological signal amplifier.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1835 Physiological...

21 CFR 882.1845 - Physiological signal conditioner.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Physiological signal conditioner. 882.1845 Section 882.1845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1845 Physiological...

21 CFR 882.1835 - Physiological signal amplifier.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Physiological signal amplifier. 882.1835 Section 882.1835 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1835 Physiological...

21 CFR 882.1845 - Physiological signal conditioner.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Physiological signal conditioner. 882.1845 Section 882.1845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1845 Physiological...

Evaluation of type II thyroplasty on phonatory physiology in an excised canine larynx model

PubMed Central

Devine, Erin E.; Hoffman, Matthew R.; McCulloch, Timothy M.; Jiang, Jack J.

2016-01-01

Objective Type II thyroplasty is an alternative treatment for spasmodic dysphonia, addressing hyperadduction by incising and lateralizing the thyroid cartilage. We quantified the effect of lateralization width on phonatory physiology using excised canine larynges. Methods Normal closure, hyperadduction, and type II thyroplasty (lateralized up to 5mm at 1mm increments with hyperadducted arytenoids) were simulated in excised larynges (N=7). Aerodynamic, acoustic, and videokymographic data were recorded at three subglottal pressures relative to phonation threshold pressure (PTP). One-way repeated measures ANOVA assessed effect of condition on aerodynamic parameters. Random intercepts linear mixed effects models assessed effects of condition and subglottal pressure on acoustic and videokymographic parameters. Results PTP differed across conditions (p<0.001). Condition affected percent shimmer (p<0.005) but not percent jitter. Both pressure (p<0.03) and condition (p<0.001) affected fundamental frequency. Pressure affected vibratory amplitude (p<0.05) and intra-fold phase difference (p<0.05). Condition affected phase difference between the vocal folds (p<0.001). Conclusions Hyperadduction increased PTP and worsened perturbation compared to normal, with near normal physiology restored with 1mm lateralization. Further lateralization deteriorated voice quality and increased PTP. Acoustic and videokymographic results indicate that normal physiologic relationships between subglottal pressure and vibration are preserved at optimal lateralization width, but then degrade with further lateralization. The 1mm optimal width observed here is due to the small canine larynx size. Future human trials would likely demonstrate a greater optimal width, with patient-specific value potentially determined based on larynx size and symptom severity. PMID:27223665

Psychological and physiological effect in humans of touching plant foliage - using the semantic differential method and cerebral activity as indicators

PubMed Central

2013-01-01

Background Numerous studies have reported on the healing powers of plants and nature, but there have not been so many instances of experimental research. In particular, there are very few psychological and physiological studies using tactile stimuli. This study examines the psychological and physiological effects of touching plant foliage by using an evaluation profile of the subjects’ impressions and investigating cerebral blood flow. Methods The subjects were 14 young Japanese men aged from 21 to 27 years (mean ± standard deviation: 23.6 ± 2.4). With their eyes closed, the subjects touched four different tactile samples including a leaf of natural pothos (Epipremnum aureum). The physiological indices were compared before and after each stimulus. Psychological indices were obtained using a ‘semantic differential’ method. Results The fabric stimulus gave people ‘soft’ and ‘rough’ impressions, ‘kind’, ‘peaceful’ and ‘pleasant’ feelings psychologically, and a sense of physiological calm. On the other hand, the metal stimulus gave people ‘cold’, ‘smooth’ and ‘hard’ impressions and an image of something ‘artificial’. The metal stimulus caused a stress response in human cerebral blood flow although its evaluation in terms of ‘pleasant or unpleasant’ was neutral. There were no remarkable differences between the stimuli of natural and artificial pothos compared with other types of stimulus psychologically. However, only the natural pothos stimulus showed a sense of physiological calm in the same appearance as the fabric stimulus. Conclusions This study shows that people experience an unconscious calming reaction to touching a plant. It is to be concluded that plants are an indispensable element of the human environment. PMID:23587233

Commensal bacteria produce GPCR ligands that mimic human signaling molecules

PubMed Central

Cohen, Louis J.; Esterhazy, Daria; Kim, Seong-Hwan; Lemetre, Christophe; Aguilar, Rhiannon R.; Gordon, Emma A.; Pickard, Amanda J.; Cross, Justin R.; Emiliano, Ana B.; Han, Sun M.; Chu, John; Vila-Farres, Xavier; Kaplitt, Jeremy; Rogoz, Aneta; Calle, Paula Y.; Hunter, Craig; Bitok, J. Kipchirchir; Brady, Sean F.

2017-01-01

Summary Statement Commensal bacteria are believed to play important roles in human health. The mechanisms by which they affect mammalian physiology are poorly understood; however, bacterial metabolites are likely to be key components of host interactions. Here, we use bioinformatics and synthetic biology to mine the human microbiota for N-acyl amides that interact with G-protein-coupled receptors (GPCRs). We found that N-acyl amide synthase genes are enriched in gastrointestinal bacteria and the lipids they encode interact with GPCRs that regulate gastrointestinal tract physiology. Mouse and cell-based models demonstrate that commensal GPR119 agonists regulate metabolic hormones and glucose homeostasis as efficiently as human ligands although future studies are needed to define their potential physiologic role in humans. This work suggests that chemical mimicry of eukaryotic signaling molecules may be common among commensal bacteria and that manipulation of microbiota genes encoding metabolites that elicit host cellular responses represents a new small molecule therapeutic modality (microbiome-biosynthetic-gene-therapy). PMID:28854168

Early caregiving and physiological stress responses.

PubMed

Luecken, Linda J; Lemery, Kathryn S

2004-05-01

Inadequate early caregiving has been associated with risks of stress-related psychological and physical illness over the life span. Dysregulated physiological stress responses may represent a mechanism linking early caregiving to health outcomes. This paper reviews evidence linking early caregiving to physiological responses that can increase vulnerability to stress-related illness. A number of high-risk family characteristics, including high conflict, divorce, abuse, and parental psychopathology, are considered in the development of stress vulnerability. Three theoretical pathways linking caregiving to physiological stress responses are outlined: genetic, psychosocial, and cognitive-affective. Exciting preliminary evidence suggests that early caregiving can impact long-term physiological stress responses. Directions for future research in this area are suggested.

Academic Performance in Human Anatomy and Physiology Classes: A 2-Yr Study of Academic Motivation and Grade Expectation

ERIC Educational Resources Information Center

Sturges, Diana; Maurer, Trent W.; Allen, Deborah; Gatch, Delena Bell; Shankar, Padmini

2016-01-01

This project used a nonexperimental design with a convenience sample and studied the relationship between academic motivation, grade expectation, and academic performance in 1,210 students enrolled in undergraduate human anatomy and physiology (HAP) classes over a 2-yr period. A 42-item survey that included 28 items of the adapted academic…

Interteaching within a Human Physiology Course: A Comparison of First- and Second-Year Students' Learning Skills and Perceptions

ERIC Educational Resources Information Center

Byrne, Bruce; Guy, Richard

2016-01-01

This article describes student perceptions and outcomes in relation to the use of a novel interteaching approach. The study sample (n = 260) was taken from a large human physiology class, which included both first- and second-year students. However, unlike the first-year students, the second-year students had significant prior knowledge, having…

Imagination in human social cognition, autism, and psychotic-affective conditions.

PubMed

Crespi, Bernard; Leach, Emma; Dinsdale, Natalie; Mokkonen, Mikael; Hurd, Peter

2016-05-01

Complex human social cognition has evolved in concert with risks for psychiatric disorders. Recently, autism and psychotic-affective conditions (mainly schizophrenia, bipolar disorder, and depression) have been posited as psychological 'opposites' with regard to social-cognitive phenotypes. Imagination, considered as 'forming new ideas, mental images, or concepts', represents a central facet of human social evolution and cognition. Previous studies have documented reduced imagination in autism, and increased imagination in association with psychotic-affective conditions, yet these sets of findings have yet to be considered together, or evaluated in the context of the diametric model. We first review studies of the components, manifestations, and neural correlates of imagination in autism and psychotic-affective conditions. Next, we use data on dimensional autism in healthy populations to test the hypotheses that: (1) imagination represents the facet of autism that best accounts for its strongly male-biased sex ratio, and (2) higher genetic risk of schizophrenia is associated with higher imagination, in accordance with the predictions of the diametric model. The first hypothesis was supported by a systematic review and meta-analysis showing that Imagination exhibits the strongest male bias of all Autism Quotient (AQ) subscales, in non-clinical populations. The second hypothesis was supported, for males, by associations between schizophrenia genetic risk scores, derived from a set of single-nucleotide polymorphisms, and the AQ Imagination subscale. Considered together, these findings indicate that imagination, especially social imagination as embodied in the default mode human brain network, mediates risk and diametric dimensional phenotypes of autism and psychotic-affective conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Research on gravitational physiology

NASA Technical Reports Server (NTRS)

Brown, A. H.; Dahl, A. O.

1974-01-01

The topic of gravitational plant physiology was studied through aspects of plant development (in ARABIDOPSIS) and of behavior (in HELIANTHUS) as these were affected by altered g experience. The effect of increased g levels on stem polarity (in COLEUS) was also examined.

Physiological and subjective evaluation of a human-robot object hand-over task.

PubMed

Dehais, Frédéric; Sisbot, Emrah Akin; Alami, Rachid; Causse, Mickaël

2011-11-01

In the context of task sharing between a robot companion and its human partners, the notions of safe and compliant hardware are not enough. It is necessary to guarantee ergonomic robot motions. Therefore, we have developed Human Aware Manipulation Planner (Sisbot et al., 2010), a motion planner specifically designed for human-robot object transfer by explicitly taking into account the legibility, the safety and the physical comfort of robot motions. The main objective of this research was to define precise subjective metrics to assess our planner when a human interacts with a robot in an object hand-over task. A second objective was to obtain quantitative data to evaluate the effect of this interaction. Given the short duration, the "relative ease" of the object hand-over task and its qualitative component, classical behavioral measures based on accuracy or reaction time were unsuitable to compare our gestures. In this perspective, we selected three measurements based on the galvanic skin conductance response, the deltoid muscle activity and the ocular activity. To test our assumptions and validate our planner, an experimental set-up involving Jido, a mobile manipulator robot, and a seated human was proposed. For the purpose of the experiment, we have defined three motions that combine different levels of legibility, safety and physical comfort values. After each robot gesture the participants were asked to rate them on a three dimensional subjective scale. It has appeared that the subjective data were in favor of our reference motion. Eventually the three motions elicited different physiological and ocular responses that could be used to partially discriminate them. Copyright © 2011 Elsevier Ltd and the Ergonomics Society. All rights reserved.

Human likeness: cognitive and affective factors affecting adoption of robot-assisted learning systems

NASA Astrophysics Data System (ADS)

Yoo, Hosun; Kwon, Ohbyung; Lee, Namyeon

2016-07-01

With advances in robot technology, interest in robotic e-learning systems has increased. In some laboratories, experiments are being conducted with humanoid robots as artificial tutors because of their likeness to humans, the rich possibilities of using this type of media, and the multimodal interaction capabilities of these robots. The robot-assisted learning system, a special type of e-learning system, aims to increase the learner's concentration, pleasure, and learning performance dramatically. However, very few empirical studies have examined the effect on learning performance of incorporating humanoid robot technology into e-learning systems or people's willingness to accept or adopt robot-assisted learning systems. In particular, human likeness, the essential characteristic of humanoid robots as compared with conventional e-learning systems, has not been discussed in a theoretical context. Hence, the purpose of this study is to propose a theoretical model to explain the process of adoption of robot-assisted learning systems. In the proposed model, human likeness is conceptualized as a combination of media richness, multimodal interaction capabilities, and para-social relationships; these factors are considered as possible determinants of the degree to which human cognition and affection are related to the adoption of robot-assisted learning systems.

Human heart failure with preserved ejection versus feline cardiomyopathy: what can we learn from both veterinary and human medicine?

PubMed

Prat, Valentine; Rozec, Bertrand; Gauthier, Chantal; Lauzier, Benjamin

2017-11-01

Cardiovascular affections are a growing health burden in human populations. Recent advances in cardiology have improved treatments and outcomes for myocardial infarction and arrhythmias, but other conditions still remain poorly understood. To date, the classical approach to study cardiovascular diseases involves rodent models, despite their strong differences with human cardiac physiology. In this context, this review will focus on the common traits between human and feline cardiac diseases, namely heart failure with preserved ejection fraction and feline cardiomyopathies, respectively. These two affections share similar pathological patterns and epidemiological characteristics. An improved knowledge would be of interest for both human and feline patients and could lead to the establishment of a more accurate treatment and therapeutic strategy for medical doctors and veterinary practitioners.

Resting State Correlates of Subdimensions of Anxious Affect

PubMed Central

Bijsterbosch, Janine; Smith, Stephen; Forster, Sophie; John, Oliver P.; Bishop, Sonia J.

2014-01-01

Resting state fMRI may help identify markers of risk for affective disorder. Given the comorbidity of anxiety and depressive disorders and the heterogeneity of these disorders as defined by DSM, an important challenge is to identify alterations in resting state brain connectivity uniquely associated with distinct profiles of negative affect. The current study aimed to address this by identifying differences in brain connectivity specifically linked to cognitive and physiological profiles of anxiety, controlling for depressed affect. We adopted a two-stage multivariate approach. Hierarchical clustering was used to independently identify dimensions of negative affective style and resting state brain networks. Combining the clustering results, we examined individual differences in resting state connectivity uniquely associated with subdimensions of anxious affect, controlling for depressed affect. Physiological and cognitive subdimensions of anxious affect were identified. Physiological anxiety was associated with widespread alterations in insula connectivity, including decreased connectivity between insula subregions and between the insula and other medial frontal and subcortical networks. This is consistent with the insula facilitating communication between medial frontal and subcortical regions to enable control of physiological affective states. Meanwhile, increased connectivity within a frontoparietal–posterior cingulate cortex–precunous network was specifically associated with cognitive anxiety, potentially reflecting increased spontaneous negative cognition (e.g., worry). These findings suggest that physiological and cognitive anxiety comprise subdimensions of anxiety-related affect and reveal associated alterations in brain connectivity. PMID:24168223

Anorectal physiology measurements are of no value in clinical practice. True or false?

PubMed Central

Carty, N. J.; Moran, B.; Johnson, C. D.

1994-01-01

This article examines whether there is any clinical value in anorectal physiology measurements. The function of the human rectum is poorly understood and the factors which affect function of the anal sphincters are complex. Several laboratories have reported results of anorectal physiology measurements, but there is extensive variation between normal values in different laboratories. It is argued that anorectal physiology measurements fail to meet the criteria of a useful clinical test: 1. It is not widely available to clinicians; 2. It is not possible to establish a reproducible normal range; 3. Abnormal measurements do not correlate with disease entities or explain symptoms; 4. The results are often unhelpful in diagnosis and management; 5. Clinical outcome after intervention does not correlate with alteration in the measurements obtained. On the other hand it can be argued that anorectal physiology measurements do provide information that assists in the management of conditions such as constipation, anismus, Hirschsprung's disease, faecal incontinence and tenesmus. Management based on biofeedback modification of physiological responses requires these techniques as part of the biofeedback system. There is evidence that this may be appropriate in anismus and solitary rectal ulcer syndrome. However, the assessment of these difficult conditions and the interpretation of the results are probably at present best confined to specialist units. PMID:8074392

Effects of Weightlessness on Human Fluid and Electrolyte Physiology

NASA Technical Reports Server (NTRS)

Leach, Carolyn S.; Johnson, Philip C., Jr.

1991-01-01

The changes that occur in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. A number of questions remain to be answered. At a time when plasma volume and extracellular fluid volume are contracted and salt and water intake is unrestricted. ADH does not correct the volume deficit and serum sodium decreases. Change in secretion or activity of a natriuretic factor during spaceflight is one possible explanation. Recent identification of a polypeptide hormone produced in cardiac muscle cells which is natiuretic, is hypotensive, and has an inhibitory effect on renin and aldosterone secretion has renewed interest in the role of a natriuretic factor. The role of this atrial natriuretic factor (ANF) in both long- and short-term variation in extracellular volumes and in the inability of the kidney to bring about an escape from the sodium-retaining state accompanying chronic cardiac dysfunction makes it reasonable to look for a role of ANF in the regulation of sodium during exposure to microgravity. Prostaglandin-E is another hormone that may antagonize the action of ADH. Assays of these hormones will be performed on samples from crew members in the future.

Caloric Restriction in Humans: Impact on Physiological, Psychological, and Behavioral Outcomes

PubMed Central

Ravussin, Eric

2011-01-01

Abstract The current societal environment is marked by overabundant accessibility of food coupled with a strong trend of reduced physical activity, both leading to the development of a constellation of disorders, including central obesity, insulin resistance, dyslipidemia, and hypertension (metabolic syndrome). Prolonged calorie restriction (CR) has been shown to extend both the median and maximal lifespan in a variety of lower species such as yeast, worms, fish, rats, and mice. Mechanisms of this CR-mediated lifespan extension are not fully elucidated, but possibly involve significant alterations in energy metabolism, oxidative damage, insulin sensitivity, inflammation, and functional changes in both the neuroendocrine and sympathetic nervous systems. Here we review some of the major physiological, psychological, and behavioral changes after 6 months of CR in overweight otherwise healthy volunteers. Special emphasis is given to the first completed clinical studies that have investigated the effects of controlled, high-quality energy-restricted diets on both biomarkers of longevity and on the development of chronic diseases related to age in humans. With the incremental expansion of research endeavors in the area of energy or caloric restriction, data on the effects of CR in animal models and human subjects are becoming more accessible. Antioxid. Redox Signal. 14, 275–287. PMID:20518700

Incorporating affective bias in models of human decision making

NASA Technical Reports Server (NTRS)

Nygren, Thomas E.

1991-01-01

Research on human decision making has traditionally focused on how people actually make decisions, how good their decisions are, and how their decisions can be improved. Recent research suggests that this model is inadequate. Affective as well as cognitive components drive the way information about relevant outcomes and events is perceived, integrated, and used in the decision making process. The affective components include how the individual frames outcomes as good or bad, whether the individual anticipates regret in a decision situation, the affective mood state of the individual, and the psychological stress level anticipated or experienced in the decision situation. A focus of the current work has been to propose empirical studies that will attempt to examine in more detail the relationships between the latter two critical affective influences (mood state and stress) on decision making behavior.

The conservation physiology of seed dispersal

PubMed Central

Ruxton, Graeme D.; Schaefer, H. Martin

2012-01-01

At a time when plant species are experiencing increasing challenges from climate change, land-use change, harvesting and invasive species, dispersal has become a very important aspect of plant conservation. Seed dispersal by animals is particularly important because some animals disperse seeds to suitable sites in a directed fashion. Our review has two aims: (i) to highlight the various ways plant dispersal by animals can be affected by current anthropogenic change and (ii) to show the important role of plant and (particularly) animal physiology in shaping seed–dispersal interactions. We argue that large-bodied seed dispersers may be particularly important for plant conservation because seed dispersal of large-seeded plants is often more specialized and because large-bodied animals are targeted by human exploitation and have smaller population sizes. We further argue that more specialized seed-dispersal systems on island ecosystems might be particularly at risk from climate change both owing to small population sizes involved but also owing to the likely thermal specialization, particularly on tropical islands. More generally, the inherent vulnerability of seed-dispersal mutualisms to disruption driven by environmental change (as well as their ubiquity) demands that we continue to improve our understanding of their conservation physiology. PMID:22566677

Mathematical modeling of human brain physiological data

NASA Astrophysics Data System (ADS)

Böhm, Matthias; Faltermeier, Rupert; Brawanski, Alexander; Lang, Elmar W.

2013-12-01

Recently, a mathematical model of the basic physiological processes regulating the cerebral perfusion and oxygen supply was introduced [Jung , J. Math. Biol.JMBLAJ0303-681210.1007/s00285-005-0343-5 51, 491 (2005)]. Although this model correctly describes the interdependence of arterial blood pressure (ABP) and intracranial pressure (ICP), it fails badly when it comes to explaining certain abnormal correlations seen in about 80% of the recordings of ABP together with ICP and the partial oxygen pressure (TiPO2) of the neuronal tissue, taken at an intensive care unit during neuromonitoring of patients with a severe brain trauma. Such recordings occasionally show segments, where the mean arterial blood pressure is correlated with the partial oxygen pressure in tissue but anticorrelated with the intracranial pressure. The origin of such abnormal correlations has not been fully understood yet. Here, two extensions to the previous approach are proposed which can reproduce such abnormal correlations in simulations quantitatively. Furthermore, as the simulations are based on a mathematical model, additional insight into the physiological mechanisms from which such abnormal correlations originate can be gained.

Prediction of human pharmacokinetics using physiologically based modeling: a retrospective analysis of 26 clinically tested drugs.

PubMed

De Buck, Stefan S; Sinha, Vikash K; Fenu, Luca A; Nijsen, Marjoleen J; Mackie, Claire E; Gilissen, Ron A H J

2007-10-01

The aim of this study was to evaluate different physiologically based modeling strategies for the prediction of human pharmacokinetics. Plasma profiles after intravenous and oral dosing were simulated for 26 clinically tested drugs. Two mechanism-based predictions of human tissue-to-plasma partitioning (P(tp)) from physicochemical input (method Vd1) were evaluated for their ability to describe human volume of distribution at steady state (V(ss)). This method was compared with a strategy that combined predicted and experimentally determined in vivo rat P(tp) data (method Vd2). Best V(ss) predictions were obtained using method Vd2, providing that rat P(tp) input was corrected for interspecies differences in plasma protein binding (84% within 2-fold). V(ss) predictions from physicochemical input alone were poor (32% within 2-fold). Total body clearance (CL) was predicted as the sum of scaled rat renal clearance and hepatic clearance projected from in vitro metabolism data. Best CL predictions were obtained by disregarding both blood and microsomal or hepatocyte binding (method CL2, 74% within 2-fold), whereas strong bias was seen using both blood and microsomal or hepatocyte binding (method CL1, 53% within 2-fold). The physiologically based pharmacokinetics (PBPK) model, which combined methods Vd2 and CL2 yielded the most accurate predictions of in vivo terminal half-life (69% within 2-fold). The Gastroplus advanced compartmental absorption and transit model was used to construct an absorption-disposition model and provided accurate predictions of area under the plasma concentration-time profile, oral apparent volume of distribution, and maximum plasma concentration after oral dosing, with 74%, 70%, and 65% within 2-fold, respectively. This evaluation demonstrates that PBPK models can lead to reasonable predictions of human pharmacokinetics.

Complex for monitoring visual acuity and its application for evaluation of human psycho-physiological state

NASA Astrophysics Data System (ADS)

Sorokoumov, P. S.; Khabibullin, T. R.; Tolstaya, A. M.

2017-01-01

The existing psychological theories associate the movement of a human eye with its reactions to external change: what we see, hear and feel. By analyzing the glance, we can compare the external human response (which shows the behavior of a person), and the natural reaction (that they actually feels). This article describes the complex for detection of visual activity and its application for evaluation of the psycho-physiological state of a person. The glasses with a camera capture all the movements of the human eye in real time. The data recorded by the camera are transmitted to the computer for processing implemented with the help of the software developed by the authors. The result is given in an informative and an understandable report, which can be used for further analysis. The complex shows a high efficiency and stable operation and can be used both, for the pedagogic personnel recruitment and for testing students during the educational process.

Geo-Effective Heliophysical Variations and Human Physiological State

NASA Astrophysics Data System (ADS)

Dimitrova, S.

2006-03-01

A group of 86 volunteers was examined on each working day in autumn 2001 and in spring 2002. These periods were chosen because of maximal expected geomagnetic activity. There were 26 persons in the group on a drug treatment, mainly because of hypertension. Systolic and diastolic blood pressure and heart rate were registered. Pulse pressure was calculated. Data about subjective psycho-physiological complaints of the persons examined were also gathered. Altogether 2799 recordings were obtained and analyzed. MANOVA was employed to check the significance of the influence of three factors on the physiological parameters under consideration. The factors were as follows: 1) geomagnetic activity estimated by H-component of the local geomagnetic field and divided into five levels; 2) gender - males and females; 3) presence of medication. Post hoc analysis was performed to elicit the significance of differences in the factors' levels. The average arterial blood pressure, pulse pressure and the percentage of the persons in the group with subjective psycho-physiological complaints were found to increase significantly with the increase of geomagnetic activity. The maximal increment of systolic and diastolic blood pressure was 10-11% and for pulse pressure 13.6%. Analyses revealed that females and persons on a medication were more sensitive to the increase of geomagnetic activity than respectively males and persons with no medication.

Sex differences in physiological reactivity to acute psychosocial stress in adolescence.

PubMed

Ordaz, Sarah; Luna, Beatriz

2012-08-01

Females begin to demonstrate greater negative affective responses to stress than males in adolescence. This may reflect the concurrent emergence of underlying differences in physiological response systems, including corticolimbic circuitries, the hypothalamic-pituitary-adrenal axis (HPAA), and the autonomic nervous system (ANS). This review examines when sex differences in physiological reactivity to acute psychosocial stress emerge and the directionality of these differences over development. Indeed, the literature indicates that sex differences emerge during adolescence and persist into adulthood for all three physiological response systems. However, the directionality of the differences varies by system. The emerging corticolimbic reactivity literature suggests greater female reactivity, particularly in limbic regions densely innervated by gonadal hormone receptors. In contrast, males generally show higher levels of HPAA and ANS reactivity. We argue that the contrasting directionality of corticolimbic and peripheral physiological responses may reflect specific effects of gonadal hormones on distinct systems and also sex differences in evolved behavioral responses that demand different levels of peripheral physiological activation. Studies that examine both subjective reports of negative affect and physiological responses indicate that beginning in adolescence, females respond to acute stressors with more intense negative affect than males despite their comparatively lower peripheral physiological responses. This dissociation is not clearly explained by sex differences in the strength of the relationship between physiological and subjective responses. We suggest that females' greater subjective responsivity may instead arise from a greater activity in brain regions that translate stress responses to subjective awareness in adolescence. Future research directions include investigations of the role of pubertal hormones in physiological reactivity across all systems

Sex differences in physiological reactivity to acute psychosocial stress in adolescence

PubMed Central

Ordaz, Sarah; Luna, Beatriz

2012-01-01

Summary Females begin to demonstrate greater negative affective responses to stress than males in adolescence. This may reflect the concurrent emergence of underlying differences in physiological response systems, including corticolimbic circuitries, the hypothalamic—pituitary— adrenal axis (HPAA), and the autonomic nervous system (ANS). This review examines when sex differences in physiological reactivity to acute psychosocial stress emerge and the directionality of these differences over development. Indeed, the literature indicates that sex differences emerge during adolescence and persist into adulthood for all three physiological response systems. However, the directionality of the differences varies by system. The emerging corti-colimbic reactivity literature suggests greater female reactivity, particularly in limbic regions densely innervated by gonadal hormone receptors. In contrast, males generally show higher levels of HPAA and ANS reactivity. We argue that the contrasting directionality of corticolimbic and peripheral physiological responses may reflect specific effects of gonadal hormones on distinct systems and also sex differences in evolved behavioral responses that demand different levels of peripheral physiological activation. Studies that examine both subjective reports of negative affect and physiological responses indicate that beginning in adolescence, females respond to acute stressors with more intense negative affect than males despite their comparatively lower peripheral physiological responses. This dissociation is not clearly explained by sex differences in the strength of the relationship between physiological and subjective responses. We suggest that females' greater subjective responsivity may instead arise from a greater activity in brain regions that translate stress responses to subjective awareness in adolescence. Future research directions include investigations of the role of pubertal hormones in physiological reactivity

Power-duration relationship: Physiology, fatigue, and the limits of human performance.

PubMed

Burnley, Mark; Jones, Andrew M

2018-02-01

The duration that exercise can be maintained decreases as the power requirements increase. In this review, we describe the power-duration (PD) relationship across the full range of attainable power outputs in humans. We show that a remarkably small range of power outputs is sustainable (power outputs below the critical power, CP). We also show that the origin of neuromuscular fatigue differs considerably depending on the exercise intensity domain in which exercise is performed. In the moderate domain (below the lactate threshold, LT), fatigue develops slowly and is predominantly of central origin (residing in the central nervous system). In the heavy domain (above LT but below CP), both central and peripheral (muscle) fatigue are observed. In this domain, fatigue is frequently correlated with the depletion of muscle glycogen. Severe-intensity exercise (above the CP) is associated with progressive derangements of muscle metabolic homeostasis and consequent peripheral fatigue. To counter these effects, muscle activity increases progressively, as does pulmonary oxygen uptake ([Formula: see text]), with task failure being associated with the attainment of [Formula: see text] max. Although the loss of homeostasis and thus fatigue develop more rapidly the higher the power output is above CP, the metabolic disturbance and the degree of peripheral fatigue reach similar values at task failure. We provide evidence that the failure to continue severe-intensity exercise is a physiological phenomenon involving multiple interacting mechanisms which indicate a mismatch between neuromuscular power demand and instantaneous power supply. Valid integrative models of fatigue must account for the PD relationship and its physiological basis.

The effects of fluoxetine on the subjective and physiological effects of 3,4-methylenedioxymethamphetamine (MDMA) in humans.

PubMed

Tancer, Manuel; Johanson, Chris-Ellyn

2007-01-01

The purpose of this study was to investigate the role of serotonin (5-HT) in the effects of oral 3,4-methylenedioxymethamphetamine (MDMA) in humans. The subjective and physiological effects of 1.5 mg/kg MDMA were evaluated after 20 mg fluoxetine in eight recreational MDMA users in a double-blind, placebo-controlled study. During phase 1, participants were maintained on placebo for at least 5 days and tested with MDMA and placebo on separate sessions. In phase 2, the procedure was the same except fluoxetine was administered daily for at least 5 days. During sessions, placebo or fluoxetine was given 1 h before the session drug and effects were measured over the next 7 h. MDMA increased positive-like subjective effects on all the Addiction Research Center Inventory scales; Arousal, Elation, Positive Mood, and Vigor on the Profile of Mood States; Drug Liking, Friendly, Good Drug Effect, High, Stimulated, and Talkative on the Visual Analog Scale; and End-of-Session Liking and Crossover Point on the Multiple Choice Procedure. MDMA also increased measures of anxiety. On the Hallucinogenic Rating Scale, all scales except Volition were increased. MDMA also increased blood pressure and heart rate. Fluoxetine treatment attenuated most of the positive-like subjective effects including the Affect and Soma scales of the Hallucinogen Rating Scale. In addition, heart rate but not blood pressure increases were reduced. These results suggest that blockade of 5-HT reuptake by fluoxetine can dampen the effects of MDMA and further supports the role of 5-HT in its behavioral effects in humans.

Artificial gravity as a countermeasure for mitigating physiological deconditioning during long-duration space missions.

PubMed

Clément, Gilles R; Bukley, Angelia P; Paloski, William H

2015-01-01

In spite of the experience gained in human space flight since Yuri Gagarin's historical flight in 1961, there has yet to be identified a completely effective countermeasure for mitigating the effects of weightlessness on humans. Were astronauts to embark upon a journey to Mars today, the 6-month exposure to weightlessness en route would leave them considerably debilitated, even with the implementation of the suite of piece-meal countermeasures currently employed. Continuous or intermittent exposure to simulated gravitational states on board the spacecraft while traveling to and from Mars, also known as artificial gravity, has the potential for enhancing adaptation to Mars gravity and re-adaptation to Earth gravity. Many physiological functions are adversely affected by the weightless environment of spaceflight because they are calibrated for normal, Earth's gravity. Hence, the concept of artificial gravity is to provide a broad-spectrum replacement for the gravitational forces that naturally occur on the Earth's surface, thereby avoiding the physiological deconditioning that takes place in weightlessness. Because researchers have long been concerned by the adverse sensorimotor effects that occur in weightlessness as well as in rotating environments, additional study of the complex interactions among sensorimotor and other physiological systems in rotating environments must be undertaken both on Earth and in space before artificial gravity can be implemented.

Intragroup Emotions: Physiological Linkage and Social Presence.

PubMed

Järvelä, Simo; Kätsyri, Jari; Ravaja, Niklas; Chanel, Guillaume; Henttonen, Pentti

2016-01-01

We investigated how technologically mediating two different components of emotion-communicative expression and physiological state-to group members affects physiological linkage and self-reported feelings in a small group during video viewing. In different conditions the availability of second screen text chat (communicative expression) and visualization of group level physiological heart rates and their dyadic linkage (physiology) was varied. Within this four person group two participants formed a physically co-located dyad and the other two were individually situated in two separate rooms. We found that text chat always increased heart rate synchrony but HR visualization only with non-co-located dyads. We also found that physiological linkage was strongly connected to self-reported social presence. The results encourage further exploration of the possibilities of sharing group member's physiological components of emotion by technological means to enhance mediated communication and strengthen social presence.

Physiological reactivity to faces via live and video-mediated communication in typical and atypical development.

PubMed

Riby, Deborah M; Whittle, Lisa; Doherty-Sneddon, Gwyneth

2012-01-01

The human face is a powerful elicitor of emotion, which induces autonomic nervous system responses. In this study, we explored physiological arousal and reactivity to affective facial displays shown in person and through video-mediated communication. We compared measures of physiological arousal and reactivity in typically developing individuals and those with the developmental disorders Williams syndrome (WS) and autism spectrum disorder (ASD). Participants attended to facial displays of happy, sad, and neutral expressions via live and video-mediated communication. Skin conductance level (SCL) indicated that live faces, but not video-mediated faces, increased arousal, especially for typically developing individuals and those with WS. There was less increase of SCL, and physiological reactivity was comparable for live and video-mediated faces in ASD. In typical development and WS, physiological reactivity was greater for live than for video-mediated communication. Individuals with WS showed lower SCL than typically developing individuals, suggesting possible hypoarousal in this group, even though they showed an increase in arousal for faces. The results are discussed in terms of the use of video-mediated communication with typically and atypically developing individuals and atypicalities of physiological arousal across neurodevelopmental disorder groups.

Micro-engineering a platform to reconstruct physiology and functionality of the human brain microvasculature in vitro

NASA Astrophysics Data System (ADS)

Daghighi, Yasaman; Heidari, Hossein; Taylor, Hayden

2018-02-01

A predominant unsolved challenge in tissue engineering is the need of a robust technique for producing vascular networks, particularly when modeling human brain tissue. The availability of reliable in vitro human brain microvasculature models would advance our understanding of its function and would provide a platform for highthroughput drug screening. Current strategies for modeling vascularized brain tissue suffer from limitations such as (1) culturing non-human cell lines, (2) limited multi-cell co-culture, and (3) the effects of neighboring physiologically unrealistic rigid polymeric surfaces, such as solid membranes. We demonstrate a new micro-engineered platform that can address these shortcomings. Specifically, we have designed and prototyped a molding system to enable the precise casting of 100μm-diameter coaxial hydrogel structures laden with the requisite cells to mimic a vascular lumen. Here we demonstrate that a fine wire with diameter 130 μm or a needle with outer diameter 300 μm can be used as a temporary mold insert, and agarose-collagen composite matrix can be cast around these inserts and thermally gelled. When the wire or needle is retracted under the precise positional control afforded by our system, a microchannel is formed which is then seeded with human microvascular endothelial cells. After seven days of culture these cells produce an apparently confluent monolayer on the channel walls. In principle, this platform could be used to create multilayered cellular structures. By arranging a fine wire and a hollow needle coaxially, three distinct zones could be defined in the model: first, the bulk gel surrounding the needle; then, after needle retraction, a cylindrical shell of matrix; and finally, after retraction of the wire, a lumen. Each zone could be independently cell-seeded. To this end, we have also successfully 3D cultured human astrocytes and SY5Y glial cells in our agarose-collagen matrix. Our approach ultimately promises scalable

Success stories and emerging themes in conservation physiology.

PubMed

Madliger, Christine L; Cooke, Steven J; Crespi, Erica J; Funk, Jennifer L; Hultine, Kevin R; Hunt, Kathleen E; Rohr, Jason R; Sinclair, Brent J; Suski, Cory D; Willis, Craig K R; Love, Oliver P

2016-01-01

The potential benefits of physiology for conservation are well established and include greater specificity of management techniques, determination of cause-effect relationships, increased sensitivity of health and disturbance monitoring and greater capacity for predicting future change. While descriptions of the specific avenues in which conservation and physiology can be integrated are readily available and important to the continuing expansion of the discipline of 'conservation physiology', to date there has been no assessment of how the field has specifically contributed to conservation success. However, the goal of conservation physiology is to foster conservation solutions and it is therefore important to assess whether physiological approaches contribute to downstream conservation outcomes and management decisions. Here, we present eight areas of conservation concern, ranging from chemical contamination to invasive species to ecotourism, where physiological approaches have led to beneficial changes in human behaviour, management or policy. We also discuss the shared characteristics of these successes, identifying emerging themes in the discipline. Specifically, we conclude that conservation physiology: (i) goes beyond documenting change to provide solutions; (ii) offers a diversity of physiological metrics beyond glucocorticoids (stress hormones); (iii) includes approaches that are transferable among species, locations and times; (iv) simultaneously allows for human use and benefits to wildlife; and (v) is characterized by successes that can be difficult to find in the primary literature. Overall, we submit that the field of conservation physiology has a strong foundation of achievements characterized by a diversity of conservation issues, taxa, physiological traits, ecosystem types and spatial scales. We hope that these concrete successes will encourage the continued evolution and use of physiological tools within conservation-based research and management

Anatomy and Physiology. Module Set I: Introduction to Anatomy and Physiology. Teacher Edition [and] Student Edition. Surgical Technology.

ERIC Educational Resources Information Center

Hilley, Robert

This document, which is the first part in a two-part set of modules on anatomy and physiology for future surgical technicians, contains the teacher and student editions of an introduction to anatomy and physiology that consists of modules on the following topics: (1) organization of the human body; (2) biochemistry and microbiology; (3) infection,…

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)…

Mathematical modeling and spectrum analysis of the physiological patello-femoral pulse train produced by slow knee movement.

PubMed

Zhang, Y T; Frank, C B; Rangayyan, R M; Bell, G D

1992-09-01

Analysis of vibration signals emitted by the knee joint has the potential for the development of a noninvasive procedure for the diagnosis and monitoring of knee pathology. In order to obtain as much information as possible from the power density spectrum of the knee vibration signal, it is necessary to identify the physiological factors (or physiologically relevant parameters) that shape the spectrum. This paper presents a mathematical model for knee vibration signals, in particular the physiological patello-femoral pulse (PFP) train produced by slow knee movement. It demonstrates through the mathematical model that the repetition rate of the physiological PFP train introduces repeated peaks in the power spectrum, and that it affects the spectrum mainly at low frequencies. The theoretical results also show that the spectral peaks at multiples of the PFP repetition rate become more evident when the variance of the interpulse interval (IPI) is small, and that these spectral peaks shift toward higher frequencies with increasing PFP repetition rates. To evaluate the mathematical model, a simulation algorithm was developed, which generates PFP signals with adjustable repetition rate and IPI variance. Signals generated by simulation were seen to possess representative spectral characteristics typically observed in physiological PFP signals. This simulation procedure allows an interactive examination of several factors which affect the PFP train spectrum. Finally, in vivo measurements of physiological PFP signals of normal volunteers are presented. Results of simulations and analysis of signals recorded from human subjects support the mathematical model's prediction that the IPI statistics play a very significant role in determining the low-end power spectrum of the physiological PFP signal.(ABSTRACT TRUNCATED AT 250 WORDS)

MRI-based three-dimensional thermal physiological characterization of thyroid gland of human body.

PubMed

Jin, Chao; He, Zhi Zhu; Yang, Yang; Liu, Jing

2014-01-01

This article is dedicated to present a MRI (magnetic resonance imaging) based three-dimensional finite element modeling on the thermal manifestations relating to the pathophysiology of thyroid gland. An efficient approach for identifying the metabolic dysfunctions of thyroid has also been demonstrated through tracking the localized non-uniform thermal distribution or enhanced dynamic imaging. The temperature features over the skin surface and thyroid domain have been characterized using the numerical simulation and experimental measurement which will help better interpret the thermal physiological mechanisms of the thyroid under steady-state or water-cooling condition. Further, parametric simulations on the hypermetabolism symptoms of hyperthyroidism and thermal effects within thyroid domain caused by varying breathing airflow in the trachea and blood-flow in artery and vein were performed. It was disclosed that among all the parameters, the airflow volume has the largest effect on the total heat flux of thyroid surface. However, thermal contributions caused by varying the breathing frequency and blood-flow velocity are negligibly small. The present study suggests a generalized way for simulating the close to reality physiological behavior or process of human thyroid, which is of significance for disease diagnosis and treatment planning. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Social relationships and physiological determinants of longevity across the human life span

PubMed Central

Yang, Yang Claire; Boen, Courtney; Gerken, Karen; Li, Ting; Schorpp, Kristen; Harris, Kathleen Mullan

2016-01-01

Two decades of research indicate causal associations between social relationships and mortality, but important questions remain as to how social relationships affect health, when effects emerge, and how long they last. Drawing on data from four nationally representative longitudinal samples of the US population, we implemented an innovative life course design to assess the prospective association of both structural and functional dimensions of social relationships (social integration, social support, and social strain) with objectively measured biomarkers of physical health (C-reactive protein, systolic and diastolic blood pressure, waist circumference, and body mass index) within each life stage, including adolescence and young, middle, and late adulthood, and compare such associations across life stages. We found that a higher degree of social integration was associated with lower risk of physiological dysregulation in a dose–response manner in both early and later life. Conversely, lack of social connections was associated with vastly elevated risk in specific life stages. For example, social isolation increased the risk of inflammation by the same magnitude as physical inactivity in adolescence, and the effect of social isolation on hypertension exceeded that of clinical risk factors such as diabetes in old age. Analyses of multiple dimensions of social relationships within multiple samples across the life course produced consistent and robust associations with health. Physiological impacts of structural and functional dimensions of social relationships emerge uniquely in adolescence and midlife and persist into old age. PMID:26729882

Social relationships and physiological determinants of longevity across the human life span.

PubMed

Yang, Yang Claire; Boen, Courtney; Gerken, Karen; Li, Ting; Schorpp, Kristen; Harris, Kathleen Mullan

2016-01-19

Two decades of research indicate causal associations between social relationships and mortality, but important questions remain as to how social relationships affect health, when effects emerge, and how long they last. Drawing on data from four nationally representative longitudinal samples of the US population, we implemented an innovative life course design to assess the prospective association of both structural and functional dimensions of social relationships (social integration, social support, and social strain) with objectively measured biomarkers of physical health (C-reactive protein, systolic and diastolic blood pressure, waist circumference, and body mass index) within each life stage, including adolescence and young, middle, and late adulthood, and compare such associations across life stages. We found that a higher degree of social integration was associated with lower risk of physiological dysregulation in a dose-response manner in both early and later life. Conversely, lack of social connections was associated with vastly elevated risk in specific life stages. For example, social isolation increased the risk of inflammation by the same magnitude as physical inactivity in adolescence, and the effect of social isolation on hypertension exceeded that of clinical risk factors such as diabetes in old age. Analyses of multiple dimensions of social relationships within multiple samples across the life course produced consistent and robust associations with health. Physiological impacts of structural and functional dimensions of social relationships emerge uniquely in adolescence and midlife and persist into old age.

The use of team-based, guided inquiry learning to overcome educational disadvantages in learning human physiology: a structural equation model.

PubMed

Rathner, Joseph A; Byrne, Graeme

2014-09-01

The study of human bioscience is viewed as a crucial curriculum in allied health. Nevertheless, bioscience (and particularly physiology) is notoriously difficult for undergraduates, particularly academically disadvantaged students. So endemic are the high failure rates (particularly in nursing) that it has come to be known as "the human bioscience problem." In the present report, we describe the outcomes for individual success in studying first-year human physiology in a subject that emphasises team-based active learning as the major pedagogy for mastering subject learning outcomes. Structural equation modeling was used to develop a model of the impact team learning had on individual performance. Modeling was consistent with the idea that students with similar academic abilities (as determined by tertiary entrance rank) were advantaged (scored higher on individual assessment items) by working in strong teams (teams that scored higher in team-based assessments). Analysis of covariance revealed that students who studied the subject with active learning as the major mode of learning activities outperformed students who studied the subject using the traditional didactic teaching format (lectures and tutorials, P = 0.000). After adjustment for tertiary entrance rank (via analysis of covariance) on two individual tests (the final exam and a late-semester in-class test), individual student grades improved by 8% (95% confidence interval: 6-10%) and 12% (95% confidence interval: 10-14%) when students engaged in team-based active learning. These data quantitatively support the notion that weaker students working in strong teams can overcome their educational disadvantages. Copyright © 2014 The American Physiological Society.

Accelerated generation of human induced pluripotent stem cells with retroviral transduction and chemical inhibitors under physiological hypoxia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shimada, Hidenori; Hashimoto, Yoshiya; Nakada, Akira

2012-01-13

Highlights: Black-Right-Pointing-Pointer Very rapid generation of human iPS cells under optimized conditions. Black-Right-Pointing-Pointer Five chemical inhibitors under hypoxia boosted reprogramming. Black-Right-Pointing-Pointer We performed genome-wide DNA methylation analysis. -- Abstract: Induced pluripotent stem (iPS) cells are generated from somatic cells by the forced expression of a defined set of pluripotency-associated transcription factors. Human iPS cells can be propagated indefinitely, while maintaining the capacity to differentiate into all cell types in the body except for extra-embryonic tissues. This technology not only represents a new way to use individual-specific stem cells for regenerative medicine but also constitutes a novel method to obtain largemore » amounts of disease-specific cells for biomedical research. Despite their great potential, the long reprogramming process (up to 1 month) remains one of the most significant challenges facing standard virus-mediated methodology. In this study, we report the accelerated generation of human iPS cells from adipose-derived stem (ADS) cells, using a new combination of chemical inhibitors under a setting of physiological hypoxia in conjunction with retroviral transduction of Oct4, Sox2, Klf4, and L-Myc. Under optimized conditions, we observed human embryonic stem (ES)-like cells as early as 6 days after the initial retroviral transduction. This was followed by the emergence of fully reprogrammed cells bearing Tra-1-81-positive and DsRed transgene-silencing properties on day 10. The resulting cell lines resembled human ES cells in many respects including proliferation rate, morphology, pluripotency-associated markers, global gene expression patterns, genome-wide DNA methylation states, and the ability to differentiate into all three of the germ layers, both in vitro and in vivo. Our method, when combined with chemical inhibitors under conditions of physiological hypoxia, offers a powerful tool for

A physiologically based model for temporal envelope encoding in human primary auditory cortex.

PubMed

Dugué, Pierre; Le Bouquin-Jeannès, Régine; Edeline, Jean-Marc; Faucon, Gérard

2010-09-01

Communication sounds exhibit temporal envelope fluctuations in the low frequency range (<70 Hz) and human speech has prominent 2-16 Hz modulations with a maximum at 3-4 Hz. Here, we propose a new phenomenological model of the human auditory pathway (from cochlea to primary auditory cortex) to simulate responses to amplitude-modulated white noise. To validate the model, performance was estimated by quantifying temporal modulation transfer functions (TMTFs). Previous models considered either the lower stages of the auditory system (up to the inferior colliculus) or only the thalamocortical loop. The present model, divided in two stages, is based on anatomical and physiological findings and includes the entire auditory pathway. The first stage, from the outer ear to the colliculus, incorporates inhibitory interneurons in the cochlear nucleus to increase performance at high stimuli levels. The second stage takes into account the anatomical connections of the thalamocortical system and includes the fast and slow excitatory and inhibitory currents. After optimizing the parameters of the model to reproduce the diversity of TMTFs obtained from human subjects, a patient-specific model was derived and the parameters were optimized to effectively reproduce both spontaneous activity and the oscillatory part of the evoked response. Copyright (c) 2010 Elsevier B.V. All rights reserved.

CO2 and temperature effects on morphological and physiological traits affecting risk of drought-induced mortality.

PubMed

Duan, Honglang; Chaszar, Brian; Lewis, James D; Smith, Renee A; Huxman, Travis E; Tissue, David T

2018-04-26

Despite a wealth of eco-physiological assessments of plant response to extreme drought, few studies have addressed the interactive effects of global change factors on traits driving mortality. To understand the interaction between hydraulic and carbon metabolic traits influencing tree mortality, which may be independently influenced by atmospheric [CO2] and temperature, we grew Eucalyptus sideroxylon A. Cunn. ex Woolls from seed in a full-factorial [CO2] (280, 400 and 640 μmol mol-1, Cp, Ca and Ce, respectively) and temperature (ambient and ambient +4 °C, Ta and Te, respectively) experiment. Prior to drought, growth across treatment combinations resulted in significant variation in physiological and morphological traits, including photosynthesis (Asat), respiration (Rd), stomatal conductance, carbohydrate storage, biomass and leaf area (LA). Ce increased Asat, LA and leaf carbohydrate concentration compared with Ca, while Cp generated the opposite response; Te reduced Rd. However, upon imposition of drought, Te hastened mortality (9 days sooner compared with Ta), while Ce significantly exacerbated drought stress when combined with Te. Across treatments, earlier time-to-mortality was mainly associated with lower (more negative) leaf water potential (Ψl) during the initial drought phase, along with higher water loss across the first 3 weeks of water limitation. Among many variables, Ψl was more important than carbon status in predicting time-to-mortality across treatments, yet leaf starch was associated with residual variation within treatments. These results highlight the need to carefully consider the integration, interaction and hierarchy of traits contributing to mortality, along with their responses to environmental drivers. Both morphological traits, which influence soil resource extraction, and physiological traits, which affect water-for-carbon exchange to the atmosphere, must be considered to adequately predict plant response to drought. Researchers have

Authorized Course of Instruction for the Quinmester Program. Science: Introduction to Anatomy and Physiology; Human Reproduction; Man and Disease; Man's Senses; and Introduction to the Human Body.

ERIC Educational Resources Information Center

Dade County Public Schools, Miami, FL.

Performance objectives are stated for each of the five secondary school units included in this package of instructional guides prepared for the Dade County Florida Quinmester Program. All five units are concerned with aspects of physiology; three require no prerequisite study of biology ("Introduction to the Human Body,""Man and…

Dietary fibers from mushroom Sclerotia: 2. In vitro mineral binding capacity under sequential simulated physiological conditions of the human gastrointestinal tract.

PubMed

Wong, Ka-Hing; Cheung, Peter C K

2005-11-30

The in vitro mineral binding capacity of three novel dietary fibers (DFs) prepared from mushroom sclerotia, namely, Pleurotus tuber-regium, Polyporous rhinocerus, and Wolfiporia cocos, to Ca, Mg, Cu, Fe, and Zn under sequential simulated physiological conditions of the human stomach, small intestine, and colon was investigated and compared. Apart from releasing most of their endogenous Ca (ranged from 96.9 to 97.9% removal) and Mg (ranged from 95.9 to 96.7% removal), simulated physiological conditions of the stomach also attenuated the possible adverse binding effect of the three sclerotial DFs to the exogenous minerals by lowering their cation-exchange capacity (ranged from 20.8 to 32.3%) and removing a substantial amount of their potential mineral chelators including protein (ranged from 16.2 to 37.8%) and phytate (ranged from 58.5 to 64.2%). The in vitro mineral binding capacity of the three sclerotial DF under simulated physiological conditions of small intestine was found to be low, especially for Ca (ranged from 4.79 to 5.91% binding) and Mg (ranged from 3.16 to 4.18% binding), and was highly correlated (r > 0.97) with their residual protein contents. Under simulated physiological conditions of the colon with slightly acidic pH (5.80), only bound Ca was readily released (ranged from 34.2 to 72.3% releasing) from the three sclerotial DFs, and their potential enhancing effect on passive Ca absorption in the human large intestine was also discussed.

A single high dose of dexamethasone affects the phosphorylation state of glutamate AMPA receptors in the human limbic system

PubMed Central

Lopes, M W; Leal, R B; Guarnieri, R; Schwarzbold, M L; Hoeller, A; Diaz, A P; Boos, G L; Lin, K; Linhares, M N; Nunes, J C; Quevedo, J; Bortolotto, Z A; Markowitsch, H J; Lightman, S L; Walz, R

2016-01-01

Glucocorticoids (GC) released during stress response exert feedforward effects in the whole brain, but particularly in the limbic circuits that modulates cognition, emotion and behavior. GC are the most commonly prescribed anti-inflammatory and immunosuppressant medication worldwide and pharmacological GC treatment has been paralleled by the high incidence of acute and chronic neuropsychiatric side effects, which reinforces the brain sensitivity for GC. Synapses can be bi-directionally modifiable via potentiation (long-term potentiation, LTP) or depotentiation (long-term depression, LTD) of synaptic transmission efficacy, and the phosphorylation state of Ser831 and Ser845 sites, in the GluA1 subunit of the glutamate AMPA receptors, are a critical event for these synaptic neuroplasticity events. Through a quasi-randomized controlled study, we show that a single high dexamethasone dose significantly reduces in a dose-dependent manner the levels of GluA1-Ser831 phosphorylation in the amygdala resected during surgery for temporal lobe epilepsy. This is the first report demonstrating GC effects on key markers of synaptic neuroplasticity in the human limbic system. The results contribute to understanding how GC affects the human brain under physiologic and pharmacologic conditions. PMID:27959333

Human NK Cell Subset Functions Are Differentially Affected by Adipokines

PubMed Central

Huebner, Lena; Engeli, Stefan; Wrann, Christiane D.; Goudeva, Lilia; Laue, Tobias; Kielstein, Heike

2013-01-01

Background Obesity is a risk factor for various types of infectious diseases and cancer. The increase in adipose tissue causes alterations in both adipogenesis and the production of adipocyte-secreted proteins (adipokines). Since natural killer (NK) cells are the host’s primary defense against virus-infected and tumor cells, we investigated how adipocyte-conditioned medium (ACM) affects functions of two distinct human NK cell subsets. Methods Isolated human peripheral blood mononuclear cells (PBMCs) were cultured with various concentrations of human and murine ACM harvested on two different days during adipogenesis and analyzed by fluorescent-activated cell sorting (FACS). Results FACS analyses showed that the expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), granzyme A (GzmA) and interferon (IFN)-γ in NK cells was regulated in a subset-specific manner. ACM treatment altered IFN-γ expression in CD56dim NK cells. The production of GzmA in CD56bright NK cells was differentially affected by the distinct adipokine compositions harvested at different states of adipogenesis. Comparison of the treatment with either human or murine ACM revealed that adipokine-induced effects on NK cell expression of the leptin receptor (Ob-R), TRAIL and IFN-γ were species-specific. Conclusion Considering the growing prevalence of obesity and the various disorders related to it, the present study provides further insights into the roles human NK cell subsets play in the obesity-associated state of chronic low-grade inflammation. PMID:24098717

The brain's emotional foundations of human personality and the Affective Neuroscience Personality Scales.

PubMed

Davis, Kenneth L; Panksepp, Jaak

2011-10-01

Six of the primary-process subcortical brain emotion systems - SEEKING, RAGE, FEAR, CARE, GRIEF and PLAY - are presented as foundational for human personality development, and hence as a potentially novel template for personality assessment as in the Affective Neurosciences Personality Scales (ANPS), described here. The ANPS was conceptualized as a potential clinical research tool, which would help experimentalists and clinicians situate subjects and clients in primary-process affective space. These emotion systems are reviewed in the context of a multi-tiered framing of consciousness spanning from primary affect, which encodes biological valences, to higher level tertiary (thought mediated) processing. Supporting neuroscience research is presented along with comparisons to Cloninger's Temperament and Character Inventory and the Five Factor Model (FFM). Suggestions are made for grounding the internal structure of the FFM on the primal emotional systems recognized in affective neuroscience, which may promote substantive dialog between human and animal research traditions. Personality is viewed in the context of Darwinian "continuity" with the inherited subcortical brain emotion systems being foundational, providing major forces for personality development in both humans and animals, and providing an affective infrastructure for an expanded five factor descriptive model applying to normal and clinical human populations as well as mammals generally. Links with ontogenetic and epigenetic models of personality development are also presented. Potential novel clinical applications of the CARE maternal-nurturance system and the PLAY system are also discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Intragroup Emotions: Physiological Linkage and Social Presence

PubMed Central

Järvelä, Simo; Kätsyri, Jari; Ravaja, Niklas; Chanel, Guillaume; Henttonen, Pentti

2016-01-01

We investigated how technologically mediating two different components of emotion—communicative expression and physiological state—to group members affects physiological linkage and self-reported feelings in a small group during video viewing. In different conditions the availability of second screen text chat (communicative expression) and visualization of group level physiological heart rates and their dyadic linkage (physiology) was varied. Within this four person group two participants formed a physically co-located dyad and the other two were individually situated in two separate rooms. We found that text chat always increased heart rate synchrony but HR visualization only with non-co-located dyads. We also found that physiological linkage was strongly connected to self-reported social presence. The results encourage further exploration of the possibilities of sharing group member's physiological components of emotion by technological means to enhance mediated communication and strengthen social presence. PMID:26903913

Success stories and emerging themes in conservation physiology

PubMed Central

Madliger, Christine L.; Cooke, Steven J.; Crespi, Erica J.; Funk, Jennifer L.; Hultine, Kevin R.; Hunt, Kathleen E.; Rohr, Jason R.; Sinclair, Brent J.; Suski, Cory D.; Willis, Craig K. R.; Love, Oliver P.

2016-01-01

The potential benefits of physiology for conservation are well established and include greater specificity of management techniques, determination of cause–effect relationships, increased sensitivity of health and disturbance monitoring and greater capacity for predicting future change. While descriptions of the specific avenues in which conservation and physiology can be integrated are readily available and important to the continuing expansion of the discipline of ‘conservation physiology’, to date there has been no assessment of how the field has specifically contributed to conservation success. However, the goal of conservation physiology is to foster conservation solutions and it is therefore important to assess whether physiological approaches contribute to downstream conservation outcomes and management decisions. Here, we present eight areas of conservation concern, ranging from chemical contamination to invasive species to ecotourism, where physiological approaches have led to beneficial changes in human behaviour, management or policy. We also discuss the shared characteristics of these successes, identifying emerging themes in the discipline. Specifically, we conclude that conservation physiology: (i) goes beyond documenting change to provide solutions; (ii) offers a diversity of physiological metrics beyond glucocorticoids (stress hormones); (iii) includes approaches that are transferable among species, locations and times; (iv) simultaneously allows for human use and benefits to wildlife; and (v) is characterized by successes that can be difficult to find in the primary literature. Overall, we submit that the field of conservation physiology has a strong foundation of achievements characterized by a diversity of conservation issues, taxa, physiological traits, ecosystem types and spatial scales. We hope that these concrete successes will encourage the continued evolution and use of physiological tools within conservation-based research and

Superposed epoch analysis of physiological fluctuations: possible space weather connections

NASA Astrophysics Data System (ADS)

Wanliss, James; Cornélissen, Germaine; Halberg, Franz; Brown, Denzel; Washington, Brien

2018-03-01

There is a strong connection between space weather and fluctuations in technological systems. Some studies also suggest a statistical connection between space weather and subsequent fluctuations in the physiology of living creatures. This connection, however, has remained controversial and difficult to demonstrate. Here we present support for a response of human physiology to forcing from the explosive onset of the largest of space weather events—space storms. We consider a case study with over 16 years of high temporal resolution measurements of human blood pressure (systolic, diastolic) and heart rate variability to search for associations with space weather. We find no statistically significant change in human blood pressure but a statistically significant drop in heart rate during the main phase of space storms. Our empirical findings shed light on how human physiology may respond to exogenous space weather forcing.

Superposed epoch analysis of physiological fluctuations: possible space weather connections.

PubMed

Wanliss, James; Cornélissen, Germaine; Halberg, Franz; Brown, Denzel; Washington, Brien

2018-03-01

There is a strong connection between space weather and fluctuations in technological systems. Some studies also suggest a statistical connection between space weather and subsequent fluctuations in the physiology of living creatures. This connection, however, has remained controversial and difficult to demonstrate. Here we present support for a response of human physiology to forcing from the explosive onset of the largest of space weather events-space storms. We consider a case study with over 16 years of high temporal resolution measurements of human blood pressure (systolic, diastolic) and heart rate variability to search for associations with space weather. We find no statistically significant change in human blood pressure but a statistically significant drop in heart rate during the main phase of space storms. Our empirical findings shed light on how human physiology may respond to exogenous space weather forcing.

The human milk oligosaccharides are not affected by pasteurization and freeze-drying.

PubMed

Hahn, Won-Ho; Kim, Jaehan; Song, Seunghyun; Park, Suyeon; Kang, Nam Mi

2017-11-06

Human milk oligosaccharides (HMOs) are known as important factors in neurologic and immunologic development of neonates. Moreover, freeze-drying seems to be a promising storage method to improve the processes of human milk banks. However, the effects of pasteurization and freeze-drying on HMOs were not evaluated yet. The purpose of this study is to analyze and compare the HMOs profiles of human milk collected before and after the pasteurization and freeze-drying. Totally nine fresh human milk samples were collected from three healthy mothers at the first, second, and third week after delivery. The samples were treated with Holder pasteurization and freeze-drying. HMOs profiles were analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight/time-of-flight (TOF/TOF) mass spectrometry and compared between samples collected before and after the treatments. Human milk samples showed significantly different HMO patterns between mothers. However, HMOs were not affected by lactation periods within 3 weeks after delivery (r 2  = 0.972-0.999, p < .001). Moreover, both of pasteurization and freeze-drying were found not to affect HMO patterns in a correlation analysis (r 2  = 0.989-0.999, p < .001). HMO patterns were found not to be affected by pasteurization and freeze-drying of donor milks. We hope that introducing freeze-drying to the human milk banks would be encouraged by the present study. However, the storage length without composition changes of HMOs after freeze-drying needs to be evaluated in the further studies.

Physiological responses to hypothermia.

PubMed

Wood, Thomas; Thoresen, Marianne

2015-04-01

Therapeutic hypothermia is the only treatment currently recommended for moderate or severe encephalopathy of hypoxic‒ischaemic origin in term neonates. Though the effects of hypothermia on human physiology have been explored for many decades, much of the data comes from animal or adult studies; the latter originally after accidental hypothermia, followed by application of controlled hypothermia after cardiac arrest or trauma, or during cardiopulmonary bypass. Though this work is informative, the effects of hypothermia on neonatal physiology after perinatal asphyxia must be considered in the context of a prolonged hypoxic insult that has already induced a number of significant physiological sequelae. This article reviews the effects of therapeutic hypothermia on respiratory, cardiovascular, and metabolic parameters, including glycaemic control and feeding requirements. The potential pitfalls of blood‒gas analysis and overtreatment of physiological changes in cardiovascular parameters are also discussed. Finally, the effects of hypothermia on drug metabolism are covered, focusing on how the pharmacokinetics, pharmacodynamics, and dosing requirements of drugs frequently used in neonatal intensive care may change during therapeutic hypothermia. Copyright © 2014 Elsevier Ltd. All rights reserved.

Why did Kant reject physiological explanations in his anthropology?

PubMed

Sturm, Thomas

2008-12-01

One of Kant's central tenets concerning the human sciences is the claim that one need not, and should not, use a physiological vocabulary if one studies human cognitions, feelings, desires, and actions from the point of view of his 'pragmatic' anthropology. The claim is well known, but the arguments Kant advances for it have not been closely discussed. I argue against misguided interpretations of the claim, and I present his actual reasons in favor of it. Contemporary critics of a 'physiological anthropology' reject physiological explanations of mental states as more or less epistemologically dubious. Kant does not favor such ignorance claims--and this is for the good, since none of these claims was sufficiently justified at that time. Instead, he develops an original irrelevance thesis concerning the empirical knowledge of the physiological basis of the mind. His arguments for this claim derive from his original and, up to now, little understood criticism of a certain conception of pragmatic history, related to his anthropological insights concerning our ability to create new rules of action, the social dynamics of human action, and the relative inconstancy of human nature. The irrelevance thesis also changes his views of the goal and methodology of anthropology. Kant thereby argues for a distinctive approach in quest for a general 'science of man'.

Matters of taste: bridging molecular physiology and the humanities.

PubMed

Rangachari, P K; Rangachari, Usha

2015-12-01

Taste perception was the focus of an undergraduate course in the health sciences that bridged the sciences and humanities. A problem-based learning approach was used to study the biological issues, whereas the cultural transmutations of these molecular mechanisms were explored using a variety of resources (novels, cookbooks, and films). Multiple evaluation procedures were used: problem summaries and problem-solving exercises (tripartite problem-solving exercise) for the problem-based learning component and group tasks and individual exercises for the cultural issues. Self-selected groups chose specific tasks from a prescribed list of options (setting up a journal in molecular gastronomy, developing an electronic tongue, designing a restaurant for synesthetes, organizing a farmers' market, marketing a culinary tour, framing hedonic scales, exploring changing tastes through works of art or recipe books, and crafting beers for space travel). Individual tasks were selected from a menu of options (book reviews, film reviews, conversations, creative writing, and oral exams). A few guest lecturers (wine making, cultural anthropology, film analysis, and nutritional epidemiology) added more flavor. The course was rated highly for its learning value (8.5 ± 1.2, n = 62) and helped students relate biological mechanisms to cultural issues (9.0 ± 0.9, n = 62). Copyright © 2015 The American Physiological Society.

The effect of active learning on student characteristics in a human physiology course for nonmajors.

PubMed

Wilke, R Russell

2003-12-01

This study investigated the effect of active-learning strategies on college students' achievement, motivation, and self-efficacy in a human physiology course for nonmajors. Variables were studied via a quasi-experimental, Solomon four-group design on 141 students at a small west-Texas university. Treatment groups were taught using a continuum-based, active-learning model implemented over the course of a semester. Control groups were taught using traditional didactic lecture methods. To assess the effects of the continuum-based active learning strategies, students were administered a comprehensive physiology content exam, the Motivated Strategies for Learning Questionnaire, and attitude surveys. Factorial analyses indicated that the treatment groups acquired significantly more content knowledge and were significantly more self-efficacious than students in the control groups. There were no significant differences in motivation. Attitude surveys indicated that students in both the treatment and control groups demonstrated a positive attitude toward active learning, believed it helped (or would help) them to learn the material, and would choose an active learning course in the future.

Allocation, stress tolerance and carbon transport in plants: how does phloem physiology affect plant ecology?

PubMed

Savage, Jessica A; Clearwater, Michael J; Haines, Dustin F; Klein, Tamir; Mencuccini, Maurizio; Sevanto, Sanna; Turgeon, Robert; Zhang, Cankui

2016-04-01

Despite the crucial role of carbon transport in whole plant physiology and its impact on plant-environment interactions and ecosystem function, relatively little research has tried to examine how phloem physiology impacts plant ecology. In this review, we highlight several areas of active research where inquiry into phloem physiology has increased our understanding of whole plant function and ecological processes. We consider how xylem-phloem interactions impact plant drought tolerance and reproduction, how phloem transport influences carbon allocation in trees and carbon cycling in ecosystems and how phloem function mediates plant relations with insects, pests, microbes and symbiotes. We argue that in spite of challenges that exist in studying phloem physiology, it is critical that we consider the role of this dynamic vascular system when examining the relationship between plants and their biotic and abiotic environment. © 2015 John Wiley & Sons Ltd.

The physiological equivalent temperature - a universal index for the biometeorological assessment of the thermal environment

NASA Astrophysics Data System (ADS)

Höppe, P.

With considerably increased coverage of weather information in the news media in recent years in many countries, there is also more demand for data that are applicable and useful for everyday life. Both the perception of the thermal component of weather as well as the appropriate clothing for thermal comfort result from the integral effects of all meteorological parameters relevant for heat exchange between the body and its environment. Regulatory physiological processes can affect the relative importance of meteorological parameters, e.g. wind velocity becomes more important when the body is sweating. In order to take into account all these factors, it is necessary to use a heat-balance model of the human body. The physiological equivalent temperature (PET) is based on the Munich Energy-balance Model for Individuals (MEMI), which models the thermal conditions of the human body in a physiologically relevant way. PET is defined as the air temperature at which, in a typical indoor setting (without wind and solar radiation), the heat budget of the human body is balanced with the same core and skin temperature as under the complex outdoor conditions to be assessed. This way PET enables a layperson to compare the integral effects of complex thermal conditions outside with his or her own experience indoors. On hot summer days, for example, with direct solar irradiation the PET value may be more than 20 K higher than the air temperature, on a windy day in winter up to 15 K lower.

Consensus and stratification in the affective meaning of human sociality

PubMed Central

Ambrasat, Jens; von Scheve, Christian; Conrad, Markus; Schauenburg, Gesche; Schröder, Tobias

2014-01-01

We investigate intrasocietal consensus and variation in affective meanings of concepts related to authority and community, two elementary forms of human sociality. Survey participants (n = 2,849) from different socioeconomic status (SES) groups in German society provided ratings of 909 social concepts along three basic dimensions of affective meaning. Results show widespread consensus on these meanings within society and demonstrate that a meaningful structure of socially shared knowledge emerges from organizing concepts according to their affective similarity. The consensus finding is further qualified by evidence for subtle systematic variation along SES differences. In relation to affectively neutral words, high-status individuals evaluate intimacy-related and socially desirable concepts as less positive and powerful than middle- or low-status individuals, while perceiving antisocial concepts as relatively more threatening. This systematic variation across SES groups suggests that the affective meaning of sociality is to some degree a function of social stratification. PMID:24843121

Network Physiology: How Organ Systems Dynamically Interact

PubMed Central

Bartsch, Ronny P.; Liu, Kang K. L.; Bashan, Amir; Ivanov, Plamen Ch.

2015-01-01

We systematically study how diverse physiologic systems in the human organism dynamically interact and collectively behave to produce distinct physiologic states and functions. This is a fundamental question in the new interdisciplinary field of Network Physiology, and has not been previously explored. Introducing the novel concept of Time Delay Stability (TDS), we develop a computational approach to identify and quantify networks of physiologic interactions from long-term continuous, multi-channel physiological recordings. We also develop a physiologically-motivated visualization framework to map networks of dynamical organ interactions to graphical objects encoded with information about the coupling strength of network links quantified using the TDS measure. Applying a system-wide integrative approach, we identify distinct patterns in the network structure of organ interactions, as well as the frequency bands through which these interactions are mediated. We establish first maps representing physiologic organ network interactions and discover basic rules underlying the complex hierarchical reorganization in physiologic networks with transitions across physiologic states. Our findings demonstrate a direct association between network topology and physiologic function, and provide new insights into understanding how health and distinct physiologic states emerge from networked interactions among nonlinear multi-component complex systems. The presented here investigations are initial steps in building a first atlas of dynamic interactions among organ systems. PMID:26555073

The Use of Team-Based, Guided Inquiry Learning to Overcome Educational Disadvantages in Learning Human Physiology: A Structural Equation Model

ERIC Educational Resources Information Center

Rathner, Joseph A.; Byrne, Graeme

2014-01-01

The study of human bioscience is viewed as a crucial curriculum in allied health. Nevertheless, bioscience (and particularly physiology) is notoriously difficult for undergraduates, particularly academically disadvantaged students. So endemic are the high failure rates (particularly in nursing) that it has come to be known as "the human…

A physiologically based pharmacokinetic model for ethylene oxide in mouse, rat, and human.

PubMed

Fennell, T R; Brown, C D

2001-06-15

Ethylene oxide (EO) is widely used as a gaseous sterilant and industrial intermediate and is a direct-acting mutagen and carcinogen. The objective of these studies was to develop physiologically based pharmacokinetic (PB-PK) models for EO to describe the exposure-tissue dose relationship in rodents and humans. We previously reported results describing in vitro and in vivo kinetics of EO metabolism in male and female F344 rats and B6C3F1 mice. These studies were extended by determining the kinetics of EO metabolism in human liver cytosol and microsomes. The results indicate enzymatically catalyzed GSH conjugation via cytosolic glutathione S-transferase (cGST) and hydrolysis via microsomal epoxide hydrolase (mEH) occur in both rodents and humans. The in vitro kinetic constants were scaled to account for cytosolic (cGST) and microsomal (mEH) protein content and incorporated into PB-PK descriptions for mouse, rat, and human. Flow-limited models adequately predicted blood and tissue EO levels, disposition, and elimination kinetics determined experimentally in rats and mice, with the exception of testis concentrations, which were overestimated. Incorporation of a diffusion-limited description for testis improved the ability of the model to describe testis concentrations. The model accounted for nonlinear increases in blood and tissue concentrations that occur in mice on exposure to EO concentrations greater than 200 ppm. Species differences are predicted in the metabolism and exposure-dose relationship, with a nonlinear relationship observed in the mouse as a result of GSH depletion. These models represent an essential step in developing a mechanistically based EO exposure-dose-response description for estimating human risk from exposure to EO. Copyright 2001 Academic Press.

Human physiological adaptation to extended Space Flight and its implications for Space Station

NASA Technical Reports Server (NTRS)

Kutyna, F. A.; Shumate, W. H.

1985-01-01

Current work evaluating short-term space flight physiological data on the homeostatic changes due to weightlessness is presented as a means of anticipating Space Station long-term effects. An integrated systems analysis of current data shows a vestibulo-sensory adaptation within days; a loss of body mass, fluids, and electrolytes, stabilizing in a month; and a loss in red cell mass over a month. But bone demineralization which did not level off is seen as the biggest concern. Computer algorithms have been developed to simulate the human adaptation to weightlessness. So far these paradigms have been backed up by flight data and it is hoped that they will provide valuable information for future Space Station design. A series of explanatory schematics is attached.

Plant-pathogen interactions: leaf physiology alterations in poplars infected with rust (Melampsora medusae).

PubMed

Gortari, Fermín; Guiamet, Juan José; Graciano, Corina

2018-06-01

Rust produced by Melampsora sp. is considered one of the most relevant diseases in poplar plantations. Growth reduction in poplar plantations takes place because rust, like other pathogens, alters leaf physiology. There is not a complete evaluation of several of the physiological traits that can be affected by rust at leaf level. Therefore, the aim of this work was to evaluate, in an integrative way and in the same pathosystem, which physiological processes are affected when Populus deltoides Bartr. ex Marsh. leaves are infected by rust (Melampsora medusae Thümen). Leaves of two clones with different susceptibility to rust were analyzed. Field and pot experiments were performed, and several physiological traits were measured in healthy and infected leaves. We conclude that rust affects leaf mesophyll integrity, and so water movement in the leaf in liquid phase is affected. As a consequence, gas exchange is reduced, affecting both carbon fixation and transpiration. However, there is an increase in respiration rate, probably due to plant and fungal respiration. The increase in respiration rate is important in the reduction of net photosynthetic rate, but also some damage in the photosynthetic apparatus limits leaf capacity to fix carbon. The decrease in chlorophyll content would start later and seems not to explain the reduction in net photosynthetic rate. Both clones, although they have different susceptibility to rust, are affected in the same physiological mechanisms.

Physiological Parameters Database for PBPK Modeling (External Review Draft)

EPA Science Inventory

EPA released for public comment a physiological parameters database (created using Microsoft ACCESS) intended to be used in PBPK modeling. The database contains physiological parameter values for humans from early childhood through senescence. It also contains similar data for an...

Monitoring Physiological Variables with Membrane Probes

NASA Technical Reports Server (NTRS)

Janle, Elsa M.

1997-01-01

This project has demonstrated the possibility of using membrane probes in rodents to monitor physiological variables for extended periods of time. The utility of these probes in physiological studies of microgravity has been demonstrated. The feasibility of developing on-line sensors has also been demonstrated and allows for the possibility of developing real-time automated monitoring systems which can be used in ground-base physiological research as well as in research and medical monitoring in space. In addition to space applications these techniques can be extended to medical monitoring in critical care situations on earth as well as facilitating research in many human and animal diseases.

Assessment and physiological state of the Posidonia oceanica meadows in Porto Cristo (Manacor, Spain)

NASA Astrophysics Data System (ADS)

Sureda, Antoni; Box, Antonio; Tejada, Silvia

2015-12-01

In the Mediterranean Sea, Posidonia oceanica is the main seagrass meadow that brings food and shelter to many species. The P. oceanica deterioration is an indicator of its own status, since it is sensitive to many disturbances, such as human impacts or alien species. Lately, oxidative stress has been pointed out as another possible biomarker of the animal and plant status. The aim of this work was to evaluate the physiological status of the P. oceanica meadows in the Porto Cristo bay (Manacor, Mallorca, Balearic Islands, Western Mediterranean), evaluating the possible impact induced by human activity performed in the area. In situ measurements were quantified (shoot density, and the maximum length and width of P. oceanica leaves) by scuba divers. Leaf samples were collected to determine the catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. The malondialdehyde (MDA) level as marker of lipid peroxidation was also evaluated. Shoot density, and length and width measurements of the leaves in the inner locations of the bay showed inferior structural features than the leaves from the outer areas. CAT, SOD and GPx enzymatic activities and lipid peroxidation were higher in leaves from the internal zones than in the outer placements. In conclusion, the general status of the of P. oceanica meadows on the Porto Cristo Bay according to structural and oxidative biomarkers evidenced a good physiological condition, although the areas nearest to the harbour and the beach reflect signs of human affection. Altogether, it reflects a good physiological condition of the meadows in the external areas of the Porto Cristo Bay.

Alliances in Human Biology: The Harvard Committee on Industrial Physiology, 1929-1939.

PubMed

Oakes, Jason

2015-08-01

In 1929 the newly-reorganized Rockefeller Foundation funded the work of a cross-disciplinary group at Harvard University called the Committee on Industrial Physiology (CIP). The committee's research and pedagogical work was oriented towards different things for different members of the alliance. The CIP program included a research component in the Harvard Fatigue Laboratory and Elton May's interpretation of the Hawthorne Studies; a pedagogical aspect as part of Wallace Donham's curriculum for Harvard Business School; and Lawrence Henderson's work with the Harvard Pareto Circle, his course Sociology 23, and the Harvard Society of Fellows. The key actors within the CIP alliance shared a concern with training men for elite careers in government service, business leadership, and academic prominence. But the first communications between the CIP and the Rockefeller Foundation did not emphasize training in human biology. Instead, the CIP presented itself as a coordinating body that would be able to organize all the varied work going on at Harvard that did not fit easily into one department, and it was on this basis that the CIP became legible to the President of Harvard, A. Lawrence Lowell, and to Rockefeller's Division of Social Sciences. The members of the CIP alliance used the term human biology for this project of research, training and institutional coordination.

Artificial gravity as a countermeasure for mitigating physiological deconditioning during long-duration space missions

PubMed Central

Clément, Gilles R.; Bukley, Angelia P.; Paloski, William H.

2015-01-01

In spite of the experience gained in human space flight since Yuri Gagarin’s historical flight in 1961, there has yet to be identified a completely effective countermeasure for mitigating the effects of weightlessness on humans. Were astronauts to embark upon a journey to Mars today, the 6-month exposure to weightlessness en route would leave them considerably debilitated, even with the implementation of the suite of piece-meal countermeasures currently employed. Continuous or intermittent exposure to simulated gravitational states on board the spacecraft while traveling to and from Mars, also known as artificial gravity, has the potential for enhancing adaptation to Mars gravity and re-adaptation to Earth gravity. Many physiological functions are adversely affected by the weightless environment of spaceflight because they are calibrated for normal, Earth’s gravity. Hence, the concept of artificial gravity is to provide a broad-spectrum replacement for the gravitational forces that naturally occur on the Earth’s surface, thereby avoiding the physiological deconditioning that takes place in weightlessness. Because researchers have long been concerned by the adverse sensorimotor effects that occur in weightlessness as well as in rotating environments, additional study of the complex interactions among sensorimotor and other physiological systems in rotating environments must be undertaken both on Earth and in space before artificial gravity can be implemented. PMID:26136665

Phase II Testing of Liquid Cooling Garments Using a Sweating Manikin, Controlled by a Human Physiological Model

NASA Technical Reports Server (NTRS)

Paul, Heather; Trevino, Luis; Bue,Grant; Rugh, John

2006-01-01

An Advanced Automotive Manikin (ADAM) developed at the National Renewable Energy Laboratory (NREL) is used to evaluate NASA's liquid cooling garments (LCGs) used in advanced space suits for extravehicular applications. The manikin has 120 separate heated/sweating zones and is controlled by a finite element physiological model of the human thermoregulatory system. Previous testing showed the thermal sensation and comfort followed the expected trends as the LCG inlet fluid temperature was changed. The Phase II test data demonstrates the repeatability of ADAM by retesting the baseline LCG. Skin and core temperature predictions using ADAM in an LCG/Arctic suit combination are compared to NASA physiological data to validate the manikin/model. Additional LCG configurations are assessed using the manikin and compared to the baseline LCG. Results can extend to other personal protective clothing, including HAZMAT suits, nuclear/biological/chemical protective suits, and fire protection suits.

Affect-Aware Adaptive Tutoring Based on Human-Automation Etiquette Strategies.

PubMed

Yang, Euijung; Dorneich, Michael C

2018-06-01

We investigated adapting the interaction style of intelligent tutoring system (ITS) feedback based on human-automation etiquette strategies. Most ITSs adapt the content difficulty level, adapt the feedback timing, or provide extra content when they detect cognitive or affective decrements. Our previous work demonstrated that changing the interaction style via different feedback etiquette strategies has differential effects on students' motivation, confidence, satisfaction, and performance. The best etiquette strategy was also determined by user frustration. Based on these findings, a rule set was developed that systemically selected the proper etiquette strategy to address one of four learning factors (motivation, confidence, satisfaction, and performance) under two different levels of user frustration. We explored whether etiquette strategy selection based on this rule set (systematic) or random changes in etiquette strategy for a given level of frustration affected the four learning factors. Participants solved mathematics problems under different frustration conditions with feedback that adapted dynamic changes in etiquette strategies either systematically or randomly. The results demonstrated that feedback with etiquette strategies chosen systematically via the rule set could selectively target and improve motivation, confidence, satisfaction, and performance more than changing etiquette strategies randomly. The systematic adaptation was effective no matter the level of frustration for the participant. If computer tutors can vary the interaction style to effectively mitigate negative emotions, then ITS designers would have one more mechanism in which to design affect-aware adaptations that provide the proper responses in situations where human emotions affect the ability to learn.

Physiology informed virtual surgical planning: a case study with a virtual airway surgical planner and BioGears

NASA Astrophysics Data System (ADS)

Potter, Lucas; Arikatla, Sreekanth; Bray, Aaron; Webb, Jeff; Enquobahrie, Andinet

2017-03-01

Stenosis of the upper airway affects approximately 1 in 200,000 adults per year1 , and occurs in neonates as well2 . Its treatment is often dictated by institutional factors and clinicians' experience or preferences 3 . Objective and quantitative methods of evaluating treatment options hold the potential to improve care in stenosis patients. Virtual surgical planning software tools are critically important for this. The Virtual Pediatric Airway Workbench (VPAW) is a software platform designed and evaluated for upper airway stenosis treatment planning. It incorporates CFD simulation and geometric authoring with objective metrics from both that help in informed evaluation and planning. However, this planner currently lacks physiological information which could impact the surgical planning outcomes. In this work, we integrated a lumped parameter, model based human physiological engine called BioGears with VPAW. We demonstrated the use of physiology informed virtual surgical planning platform for patient-specific stenosis treatment planning. The preliminary results show that incorporating patient-specific physiology in the pretreatment plan would play important role in patient-specific surgical trainers and planners in airway surgery and other types of surgery that are significantly impacted by physiological conditions during surgery.

A multi-sensor monitoring system of human physiology and daily activities.

PubMed

Doherty, Sean T; Oh, Paul

2012-04-01

To present the design and pilot test results of a continuous multi-sensor monitoring system of real-world physiological conditions and daily life (activities, travel, exercise, and food consumption), culminating in a Web-based graphical decision-support interface. The system includes a set of wearable sensors wirelessly connected to a "smartphone" with a continuously running software application that compresses and transmits the data to a central server. Sensors include a Global Positioning System (GPS) receiver, electrocardiogram (ECG), three-axis accelerometer, and continuous blood glucose monitor. A food/medicine diary and prompted recall activity diary were also used. The pilot test involved 40 type 2 diabetic patients monitored over a 72-h period. All but three subjects were successfully monitored for the full study period. Smartphones proved to be an effective hub for managing multiple streams of data but required attention to data compression and battery consumption issues. ECG, accelerometer, and blood glucose devices performed adequately as long as subjects wore them. GPS tracking for a full day was feasible, although significant efforts are needed to impute missing data. Activity detection algorithms were successful in identifying activities and trip modes but could benefit by incorporating accelerometer data. The prompted recall diary was an effective tool for augmenting algorithm results, although subjects reported some difficulties with it. The food and medicine diary was completed fully, although end times and medicine dosages were occasionally missing. The unique combination of sensors holds promise for increasing accuracy and reducing burden associated with collecting individual-level activity and physiological data under real-world conditions, but significant data processing issues remain. Such data will provide new opportunities to explore the impacts of human geography and daily lifestyle on health at a fine spatial/temporal scale.

Anthocyanins are bioavailable in humans following an acute dose of cranberry juice

USDA-ARS?s Scientific Manuscript database

Research suggests that anthocyanins from berry fruit may affect a variety of physiological responses, including endothelial function, but little information is available regarding the pharmacokinetics of these flavonoids in humans. To determine the pharmacokinetics of cranberry anthocyanins a study ...

Synthesis of nitric oxide in human osteoblasts in response to physiologic stimulation of electrotherapy.

PubMed

Hamed, Ayman; Kim, Paul; Cho, Michael

2006-12-01

Electrotherapy for bone healing, remodeling and wound healing may be mediated by modulation of nitric oxide (NO). Using NO-specific fluorophore (DAF-2), we report here that application of non-invasive, physiologic electrical stimulation induces NO synthesis in human osteoblasts, and that such NO generation is comparable to that induced by estrogen treatment. For example, application of a sinusoidal 1 Hz, 2 V/cm (peak to peak) electrical stimulation (ES) increases NO-bound DAF-2 fluorescence intensity by a 2-fold within 60 min exposure by activating nitric oxide synthase (NOS). Increase in the NO level is found to depend critically on the frequency and strength of ES. While the frequency of 1 Hz ES seems optimal, the ES strength >0.5 V/cm is required to induce significant NO increase, however. Nitric oxide synthesis in response to ES is completely prevented by blocking estrogen receptors using a competitive inhibitor, suggesting that NO generation is likely initiated by activation of estrogen receptors at the cell surface. Based on these findings, physiologic stimulation of electrotherapy appears to represent a potential non-invasive, non-genomic, and novel physical technique that could be used to regulate NO-mediated bone density and facilitate bone remodeling without adverse effects associated with hormone therapy.

A Large Radius Human Centrifuge: The Human Hypergravity Havitat

NASA Astrophysics Data System (ADS)

van Loon, J. J. W. A.

2008-06-01

Life on Earth has developed at unit gravity, 9.81 m/s2, but how would plants and animals have evolved on a larger planet, i.e. larger than Earth? We are able to address this question simply by studies using centrifuges. In the past decades numerous experiments have been performed on cells, plants and animals grown for longer durations, even multi generations, under hypergravity conditions. Based on these studies we have gained interesting insights in the physiological process of these systems when exposed to artificial gravity. Animals and plants adapt themselves to this new high-g environment. Information of adaptation to hyper-g in mammals is interesting, or maybe even proof vital, for future human space flight programs especially in light of long duration missions to Moon and Mars. We know from long duration animal studies that numerous physiological processes and structures like muscles, bones, neuro-vestibular, or the cardiovascular system are affected. However, humans have never been exposed to a hyper-g environment for long durations. Human studies are mostly in the order of hours at most. Current work on human centrifuges is all focused on short arm systems to apply artificial gravity in long duration space missions. In this paper we want to address the possible usefulness of a large radius human centrifuge on Earth, or even on Moon or Mars, for both basic research and possible applications. In such a centrifuge a group of humans may be exposed to hypergravity for, in principle, an unlimited period of time.

Physiological effects of polybrominated diphenyl ether (PBDE-47) on pregnant gartersnakes and resulting offspring.

PubMed

Neuman-Lee, Lorin A; Carr, James; Vaughn, Katelynn; French, Susannah S

2015-08-01

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants and are persistent contaminants found in virtually every environment and organism sampled to date, including humans. There is growing evidence that PBDEs are the source of thyroid, neurodevelopmental, and reproductive toxicity. Yet little work has focused on how this pervasive contaminant may influence the reproduction and physiology of non-traditional model species. This is especially critical because in many cases non-model species, such as reptiles, are most likely to come into contact with PBDEs in nature. We tested how short-term, repeated exposure to the PBDE congener BDE-47 during pregnancy affected physiological processes in pregnant female gartersnakes (thyroid follicular height, bactericidal ability, stress responsiveness, reproductive output, and tendency to terminate pregnancy) and their resulting offspring (levels of corticosterone, bactericidal ability, and size differences). We found potential effects of BDE-47 on both the mother, such as increased size and higher thyroid follicular height, and her offspring (increased size), suggesting the effects on physiological function of PBDEs do indeed extend beyond the traditional rodent models. Copyright © 2015 Elsevier Inc. All rights reserved.

Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae.

PubMed

Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

2016-01-01

Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on the impact of nano-sized plastics on marine organisms. Therefore, the present study aims to evaluate the effects of 40nm anionic carboxylated (PS-COOH) and 50nm cationic amino (PS-NH2) polystyrene nanoparticles (PS NPs) on brine shrimp Artemia franciscana larvae. No signs of mortality were observed at 48h of exposure for both PS NPs at naplius stage but several sub-lethal effects were evident. PS-COOH (5-100μg/ml) resulted massively sequestered inside the gut lumen of larvae (48h) probably limiting food intake. Some of them were lately excreted as fecal pellets but not a full release was observed. Likewise, PS-NH2 (5-100µg/ml) accumulated in larvae (48h) but also adsorbed at the surface of sensorial antennules and appendages probably hampering larvae motility. In addition, larvae exposed to PS-NH2 undergo multiple molting events during 48h of exposure compared to controls. The activation of a defense mechanism based on a physiological process able to release toxic cationic NPs (PS-NH2) from the body can be hypothesized. The general observed accumulation of PS NPs within the gut during the 48h of exposure indicates a continuous bioavailability of nano-sized PS for planktonic species as well as a potential transfer along the trophic web. Therefore, nano-sized PS might be able to impair food uptake (feeding), behavior (motility) and physiology (multiple molting) of brine shrimp larvae with consequences not only at organism and population level but on the overall ecosystem based on the key role of zooplankton on marine food webs. Copyright © 2015 Elsevier Inc. All rights reserved.

Physiological characterization of ocular melanosis-affected canine melanocytes.

PubMed

Dawson-Baglien, Ethan M; Noland, Erica L; Sledge, Dodd G; Kiupel, Matti; Petersen-Jones, Simon M

2018-04-27

Cairn terriers with ocular melanosis (OM) accumulate large, heavily pigmented melanocytes in the anterior uvea. Darkly pigmented plaques develop within the sclera, leading us to hypothesize that OM uveal melanocytes may have an abnormal migratory capacity. Globes from OM-affected Cairn terriers and unaffected control eyes enucleated for reasons unrelated to this study were used for immunohistochemistry and to culture melanocytes for in vitro cell behavior assays. The scleral plaques of six dogs were immunolabeled for HMB-45, MelanA, PNL2, CD18, CD204, and Iba-1 and compared with the pigment cells accumulated within the irides. Cultured uveal melanocytes from OM-affected and control dogs were compared using conventional assays measuring cell proliferation, invasion capability, and melanin production. Melanocytes isolated from OM eyes had significantly elevated levels of per-cell melanin content and production compared to controls. The majority of pigmented cells in the scleral plaques were HMB45 positive indicating a melanocytic origin. Many were also CD18 positive. No differences were observed between cultured melanocytes from OM-affected and control uvea for standard in vitro proliferation or invasion assays. Pigmented cells which accumulate in the sclera of OM-affected Cairn terriers are predominantly melanocytes; however, in vitro assays of uveal melanocytes did not reveal differences in migratory behavior between OM and control cells. Migratory behavior of OM-melanocytes may be environment-dependent. We suggest that RNA sequencing and differential expression analysis would be a useful next step in understanding this disease. © 2018 American College of Veterinary Ophthalmologists.

Leptin administered in physiological or pharmacological doses does not regulate circulating angiogenesis factors in humans.

PubMed

Aronis, K N; Diakopoulos, K N; Fiorenza, C G; Chamberland, J P; Mantzoros, C S

2011-09-01

Leptin has been shown to regulate angiogenesis in animal and in vitro studies by upregulating the production of several pro-angiogenic factors, but its role in regulating angiogenesis has never been studied in humans. The potential angiogenic effect of two doses of metreleptin (50 and 100 ng/ml) was evaluated in vitro, using a novel three-dimensional angiogenesis assay. Fifteen healthy, normoleptinaemic volunteers were administered both a physiological (0.1 mg/kg) and a pharmacological (0.3 mg/kg) single dose of metreleptin, in vivo, on two different inpatient admissions separated by 1-12 weeks. Serum was collected at 0, 6, 12 and 24 h after metreleptin administration. Twenty lean women, with leptin levels <5 ng/ml, were randomised in a 1:1 fashion to receive either physiological replacement doses of metreleptin (0.04-0.12 mg/kg q.d.) or placebo for 32 weeks. Serum was collected at 0, 8, 20 and 32 weeks after randomisation. Proteomic angiogenesis array analysis was performed to screen for angiogenic factors. Circulating concentrations of angiogenin, angiopoietin-1, platelet derived endothelial factor (PDGF)-AA, matrix metalloproteinase (MMP) 8 and 9, endothelial growth factor (EGF) and vascular EGF (VEGF) were also measured. Both metreleptin doses failed to induce angiogenesis in the in vitro model. Although leptin levels increased significantly in response to both short-term and long-term metreleptin administration, circulating concentrations of angiogenesis markers did not change significantly in vivo. This is the first study that examines the effect of metreleptin administration in angiogenesis in humans. Metreleptin administration does not regulate circulating angiogenesis related factors in humans. ClinicalTrials.gov NCT00140205 and NCT00130117. This study was supported by National Institutes of Health-National Center for Research Resources grant M01-RR-01032 (Harvard Clinical and Translational Science Center) and grant number UL1 RR025758. Funding was also

Modulation of Wolframin Expression in Human Placenta during Pregnancy: Comparison among Physiological and Pathological States

PubMed Central

Perna, Angelica; Iannaccone, Alessandro; Cobellis, Luigi; De Luca, Antonio

2014-01-01

The WFS1 gene, encoding a transmembrane glycoprotein of the endoplasmic reticulum called wolframin, is mutated in Wolfram syndrome, an autosomal recessive disorder defined by the association of diabetes mellitus, optic atrophy, and further organ abnormalities. Disruption of the WFS1 gene in mice causes progressive β-cell loss in the pancreas and impaired stimulus-secretion coupling in insulin secretion. However, little is known about the physiological functions of this protein. We investigated the immunohistochemical expression of wolframin in human placenta throughout pregnancy in normal women and diabetic pregnant women. In normal placenta, there was a modulation of wolframin throughout pregnancy with a strong level of expression during the first trimester and a moderate level in the third trimester of gestation. In diabetic women, wolframin expression was strongly reduced in the third trimester of gestation. The pattern of expression of wolframin in normal placenta suggests that this protein may be required to sustain normal rates of cytotrophoblast cell proliferation during the first trimester of gestation. The decrease in wolframin expression in diabetic placenta suggests that this protein may participate in maintaining the physiologic glucose homeostasis in this organ. PMID:24588001

Performance assessment techniques for Doppler radar physiological sensors.

PubMed

Hafner, Noah; Lubecke, Victor

2009-01-01

This paper presents a technique for assessing the performance of continuous wave Doppler radar systems for physiological sensing. The technique includes an artificial target for testing physiological sensing radar systems with motion analogous to human heart movement and software algorithms leveraging the capabilities of this target to simply test radar system performance. The mechanical target provides simple to complex patterns of motion that are stable and repeatable. Details of radar system performance can be assessed and the effects of configuration changes that might not appear with a human target can be observed when using this mechanical target.

"Sebocytes' makeup": novel mechanisms and concepts in the physiology of the human sebaceous glands.

PubMed

Tóth, Balázs I; Oláh, Attila; Szöllosi, Attila G; Czifra, Gabriella; Bíró, Tamás

2011-06-01

The pilosebaceous unit of the human skin consists of the hair follicle and the sebaceous gland. Within this "mini-organ", the sebaceous gland has been neglected by the researchers of the field for several decades. Actually, it was labeled as a reminiscence of human development ("a living fossil with a past but no future"), and was thought to solely act as a producer of sebum, a lipid-enriched oily substance which protects our skin (and hence the body) against various insults. However, due to emerging research activities of the past two decades, it has now become evident that the sebaceous gland is not only a "passive" cutaneous "relic" to establish the physico-chemical barrier function of the skin against constant environmental challenges, but it rather functions as an "active" neuro-immuno-endocrine cutaneous organ. This review summarizes recent findings of sebaceous gland research by mainly focusing on newly discovered physiological functions, novel regulatory mechanisms, key events in the pathology of the gland, and future directions in both experimental and clinical dermatology.

Human cold stress of strong local-wind "Hijikawa-arashi" in Japan, based on the UTCI index and thermo-physiological responses

NASA Astrophysics Data System (ADS)

Ohashi, Yukitaka; Katsuta, Takumi; Tani, Haruka; Okabayashi, Taiki; Miyahara, Satoshi; Miyashita, Ryoji

2018-03-01

We investigated the cold stress caused by a strong local wind called "Hijikawa-arashi," through in situ vital measurements and the Universal Thermal Climate Index (UTCI). This wind is a very interesting winter phenomenon, localized in an area within 1 km of the seashore in Ozu City, Ehime Prefecture in Japan. When a strong Hijikawa-arashi (HA) occurred at 14-15 m s-1, the UTCI decreased to - 30 °C along the bridge where commuting residents are the most exposed to strong and cold winds. On the bridge, most participants in our experiment felt "very cold" or "extremely cold." The UTCI of HA can be predicted from a multiple regression equation using wind speed and air temperature. The cold HA wind is also harmful to human thermo-physiological responses. It leads to higher blood pressure and increased heart rate, both of which act as cardiovascular stress triggers. Increases of 6-10 mmHg and 3-6 bpm for every 10 °C reduction in UTCI were seen on all observational days, including HA and non-HA days. In fact, the participants' body skin temperatures decreased by approximately 1.2 to 1.7 °C for every 10 °C reduction in UTCI. Thus, the UTCI variation due to the HA outbreak corresponded well with the cold sensation and thermo-physiological responses in humans. This result suggests that daily UTCI monitoring enables the prediction of thermo-physiological responses to the HA cold stress.

Functional Neuroimaging Insights into the Physiology of Human Sleep

PubMed Central

Dang-Vu, Thien Thanh; Schabus, Manuel; Desseilles, Martin; Sterpenich, Virginie; Bonjean, Maxime; Maquet, Pierre

2010-01-01

-Vu TT; Schabus M; Desseilles M; Sterpenich V; Bonjean M; Maquet P. Functional neuroimaging insights into the physiology of human sleep. SLEEP 2010;33(12):1589-1603. PMID:21120121

Using pupil size and heart rate to infer affective states during behavioral neurophysiology and neuropsychology experiments

PubMed Central

Mitz, Andrew R.; Chacko, Ravi V.; Putnam, Philip T.; Rudebeck, Peter H.; Murray, Elisabeth A.

2017-01-01

Background Nonhuman primates (NHPs) are a valuable research model because of their behavioral, physiological and neuroanatomical similarities to humans. In the absence of language, autonomic activity can provide crucial information about cognitive and affective states during single-unit recording, inactivation and lesion studies. Methods standardized for use in humans are not easily adapted to NHPs and detailed guidance has been lacking. New Method We provide guidance for monitoring heart rate and pupil size in the behavioral neurophysiology setting by addressing the methodological issues, pitfalls and solutions for NHP studies. The methods are based on comparative physiology to establish a rationale for each solution. We include examples from both electrophysiological and lesion studies. Results Single-unit recording, pupil responses and heart rate changes represent a range of decreasing temporal resolution, a characteristic that impacts experimental design and analysis. We demonstrate the unexpected result that autonomic measures acquired before and after amygdala lesions are comparable despite disruption of normal autonomic function. Comparison with Existing Methods Species and study design differences can render standard techniques used in human studies inappropriate for NHP studies. We show how to manage data from small groups typical of NHP studies, data from the short behavioral trials typical of neurophysiological studies, issues associated with longitudinal studies, and differences in anatomy and physiology. Conclusions Autonomic measurement to infer cognitive and affective states in NHP is neither off-the-shelf nor onerous. Familiarity with the issues and solutions will broaden the use of autonomic signals in NHP single unit and lesion studies. PMID:28089759

Physiological responses induced by pleasant stimuli.

PubMed

Watanuki, Shigeki; Kim, Yeon-Kyu

2005-01-01

The specific physiological responses induced by pleasant stimuli were investigated in this study. Various physiological responses of the brain (encephaloelectrogram; EEG), autonomic nervous system (ANS), immune system and endocrine system were monitored when pleasant stimuli such as odors, emotional pictures and rakugo, a typical Japanese comical story-telling, were presented to subjects. The results revealed that (i) EEG activities of the left frontal brain region were enhanced by a pleasant odor; (ii) emotional pictures related to primitive element such as nudes and erotic couples elevated vasomotor sympathetic nervous activity; and (iii) an increase in secretory immunoglobulin A (s-IgA) and a decrease in salivary cortisol (s-cortisol) were induced by rakugo-derived linguistic pleasant emotion. Pleasant emotion is complicated state. However, by considering the evolutionary history of human being, it is possible to assess and evaluate pleasant emotion from certain physiological responses by appropriately summating various physiological parameters.

Physiological effects of a bactericidal protein from human polymorphonuclear leukocytes on Pseudomonas aeruginosa.

PubMed

Hovde, C J; Gray, B H

1986-04-01

The physiological changes seen in Pseudomonas aeruginosa after exposure to a bactericidal protein (BP) from the granules of human polymorphonuclear leukocytes were studied. It was demonstrated, using radiolabeled proline or leucine, that both the rate of cellular uptake and amino acid incorporation into trichloroacetic acid-insoluble material were markedly decreased immediately after exposure to BP. The rate of O2 consumption by P. aeruginosa was decreased immediately after exposure to BP and continued to decline exponentially until it ceased completely 30 min after exposure to BP. In the presence of 30 mM CaCl2 or MgCl2, bacteria were protected from death due to BP and respiration rates were unaffected. The cellular ATP pool of P. aeruginosa remained constant for up to 2 h after exposure to BP. Membrane depolarization was measured by the influx of the lipophilic anion thiocyanate. It was shown that the cytoplasmic membrane of P. aeruginosa was partially depolarized after exposure to BP. Purified BP killed 95% of 5 X 10(6) CFU of P. aeruginosa at a concentration of 60 to 100 ng of protein per ml. Although the concentration of bacteria and BP varied with each type of experiment, the BP/bacteria ratio required to cause a 95 to 99% loss in viability remained constant. We propose that cytoplasmic membrane depolarization is the biochemical lesion responsible for the other physiological changes seen and ultimately for the death of P. aeruginosa induced by BP.

The effect of working on-call on stress physiology and sleep: A systematic review.

PubMed

Hall, Sarah J; Ferguson, Sally A; Turner, Anne I; Robertson, Samuel J; Vincent, Grace E; Aisbett, Brad

2017-06-01

On-call work is becoming an increasingly common work pattern, yet the human impacts of this type of work are not well established. Given the likelihood of calls to occur outside regular work hours, it is important to consider the potential impact of working on-call on stress physiology and sleep. The aims of this review were to collate and evaluate evidence on the effects of working on-call from home on stress physiology and sleep. A systematic search of Ebsco Host, Embase, Web of Science, Scopus and ScienceDirect was conducted. Search terms included: on-call, on call, standby, sleep, cortisol, heart rate, adrenaline, noradrenaline, nor-adrenaline, epinephrine, norepinephrine, nor-epinephrine, salivary alpha amylase and alpha amylase. Eight studies met the inclusion criteria, with only one study investigating the effect of working on-call from home on stress physiology. All eight studies investigated the effect of working on-call from home on sleep. Working on-call from home appears to adversely affect sleep quantity, and in most cases, sleep quality. However, studies did not differentiate between night's on-call from home with and without calls. Data examining the effect of working on-call from home on stress physiology were not sufficient to draw meaningful conclusions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial Community-Level Physiological Profiles (CLPP) and herbicide mineralization potential in groundwater affected by agricultural land use

NASA Astrophysics Data System (ADS)

Janniche, Gry Sander; Spliid, Henrik; Albrechtsen, Hans-Jørgen

2012-10-01

Diffuse groundwater pollution from agricultural land use may impact the microbial groundwater community, which was investigated as Community-Level Physiological Profiles (CLPP) using EcoPlate™. Water was sampled from seven piezometers and a spring in a small agricultural catchment with diffuse herbicide and nitrate pollution. Based on the Shannon-Wiener and Simpson's diversity indices the diversity in the microbial communities was high. The response from the EcoPlates™ showed which substrates support groundwater bacteria, and all 31 carbon sources were utilized by organisms from at least one water sample. However, only nine carbon sources were utilized by all water samples: D-Mannitol, N-acetyl-D-glucosamine, putrescine, D-galacturonic acid, itaconic acid, 4-hydroxy benzoic acid, tween 40, tween 80, and L-asparagine. In all water samples the microorganisms preferred D-mannitol, D-galacturonic acid, tween 40, and 4-hydroxy benzoic acid as substrates, whereas none preferred 2-hydroxy benzoic acid, α-D-lactose, D,L-α-glycerol phosphate, α-ketobutyric acid, L-threonine and glycyl-L-glutamic acid. Principal Component Analysis of the CLPP's clustered the most agriculturally affected groundwater samples, indicating that the agricultural land use affects the groundwater microbial communities. Furthermore, the ability to mineralize atrazine and isoproturon, which have been used in the catchment, was also associated with this cluster.

Investigation of clinical pharmacokinetic variability of an opioid antagonist through physiologically based absorption modeling.

PubMed

Ding, Xuan; He, Minxia; Kulkarni, Rajesh; Patel, Nita; Zhang, Xiaoyu

2013-08-01

Identifying the source of inter- and/or intrasubject variability in pharmacokinetics (PK) provides fundamental information in understanding the pharmacokinetics-pharmacodynamics relationship of a drug and project its efficacy and safety in clinical populations. This identification process can be challenging given that a large number of potential causes could lead to PK variability. Here we present an integrated approach of physiologically based absorption modeling to investigate the root cause of unexpectedly high PK variability of a Phase I clinical trial drug. LY2196044 exhibited high intersubject variability in the absorption phase of plasma concentration-time profiles in humans. This could not be explained by in vitro measurements of drug properties and excellent bioavailability with low variability observed in preclinical species. GastroPlus™ modeling suggested that the compound's optimal solubility and permeability characteristics would enable rapid and complete absorption in preclinical species and in humans. However, simulations of human plasma concentration-time profiles indicated that despite sufficient solubility and rapid dissolution of LY2196044 in humans, permeability and/or transit in the gastrointestinal (GI) tract may have been negatively affected. It was concluded that clinical PK variability was potentially due to the drug's antagonism on opioid receptors that affected its transit and absorption in the GI tract. Copyright © 2013 Wiley Periodicals, Inc.

How is physiology relevant to behavior analysis?

PubMed Central

Reese, Hayne W.

1996-01-01

Physiology is an important biological science; but behavior analysis is not a biological science, and behavior analysts can safely ignore biological processes. However, ignoring products of biological processes might be a serious mistake. The important products include behavior, instinctive drift, behavior potentials, hunger, and many developmental milestones and events. Physiology deals with the sources of such products; behavior analysis can deal with how the products affect behavior, which can be understood without understanding their sources. PMID:22478240

The Implementation of Clay Modeling and Rat Dissection into the Human Anatomy and Physiology Curriculum of a Large Urban Community College

ERIC Educational Resources Information Center

Haspel, Carol; Motoike, Howard K.; Lenchner, Erez

2014-01-01

After a considerable amount of research and experimentation, cat dissection was replaced with rat dissection and clay modeling in the human anatomy and physiology laboratory curricula at La Guardia Community College (LAGCC), a large urban community college of the City University of New York (CUNY). This article describes the challenges faculty…

Muscle sympathetic nerve responses to physiological changes in prostaglandin production in humans

NASA Technical Reports Server (NTRS)

Doerzbacher, K. J.; Ray, C. A.

2001-01-01

Previous studies suggest that prostaglandins may contribute to exercise-induced increases in muscle sympathetic nerve activity (MSNA). To test this hypothesis, MSNA was measured at rest and during exercise before and after oral administration of ketoprofen, a cyclooxygenase inhibitor, or placebo. Twenty-one subjects completed two bouts of graded dynamic and isometric handgrip to fatigue. Each exercise bout was followed by 2 min of postexercise muscle ischemia. The second exercise bouts were performed after 60 min of rest in which 11 subjects were given ketoprofen (300 mg) and 10 subjects received a placebo. Ketoprofen significantly lowered plasma thromboxane B(2) in the drug group (from 36 +/- 6 to 22 +/- 3 pg/ml, P < 0.04), whereas thromboxane B(2) in the placebo group increased from 40 +/- 5 to 61 +/- 9 pg/ml from trial 1 to trial 2 (P < 0.008). Ketoprofen and placebo did not change sympathetic and cardiovascular responses to dynamic handgrip, isometric handgrip, and postexercise muscle ischemia. There was no relationship between thromboxane B(2) concentrations and MSNA or arterial pressure responses during both exercise modes. The data indicate that physiological increases or decreases in prostaglandins do not alter exercise-induced increases in MSNA and arterial pressure in humans. These findings suggest that contraction-induced metabolites other than prostaglandins mediate MSNA responses to exercise in humans.

Anatomy and physiology of genital organs - women.

PubMed

Graziottin, Alessandra; Gambini, Dania

2015-01-01

"Anatomy is destiny": Sigmund Freud viewed human anatomy as a necessary, although not a sufficient, condition for understanding the complexity of human sexual function with a solid biologic basis. The aim of the chapter is to describe women's genital anatomy and physiology, focusing on women's sexual function with a clinically oriented vision. Key points include: embryology, stressing that the "female" is the anatomic "default" program, differentiated into "male" only in the presence of androgens at physiologic levels for the gestational age; sex determination and sex differentiation, describing the interplay between anatomic and endocrine factors; the "clitoral-urethral-vaginal" complex, the most recent anatomy reading of the corpora cavernosa pattern in women; the controversial G spot; the role of the pelvic floor muscles in modulating vaginal receptivity and intercourse feelings, with hyperactivity leading to introital dyspareunia and contributing to provoked vestibulodynia and recurrent postcoital cystitis, whilst lesions during delivery reduce vaginal sensations, genital arousability, and orgasm; innervation, vessels, bones, ligaments; and the physiology of women's sexual response. Attention to physiologic aging focuses on "low-grade inflammation," genital and systemic, with its impact on women sexual function, especially after the menopause, if the woman does not or cannot use hormone replacement therapy. © 2015 Elsevier B.V. All rights reserved.

Behavioural and physiological effects of finely balanced decision-making in chickens.

PubMed

Davies, Anna C; Nicol, Christine J; Persson, Mia E; Radford, Andrew N

2014-01-01

In humans, more difficult decisions result in behavioural and physiological changes suggestive of increased arousal, but little is known about the effect of decision difficulty in other species. A difficult decision can have a number of characteristics; we aimed to monitor how finely balanced decisions, compared to unbalanced ones, affected the behaviour and physiology of chickens. An unbalanced decision was one in which the two options were of unequal net value (1 (Q1) vs. 6 (Q6) pieces of sweetcorn with no cost associated with either option); a finely balanced decision was one in which the options were of equal net value (i.e. hens were "indifferent" to both options). To identify hens' indifference, a titration procedure was used in which a cost (electromagnetic weight on an access door) was applied to the Q6 option, to find the individual point at which hens chose this option approximately equally to Q1 via a non-weighted door. We then compared behavioural and physiological indicators of arousal (head movements, latency to choose, heart-rate variability and surface body temperature) when chickens made decisions that were unbalanced or finely balanced. Significant physiological (heart-rate variability) and behavioural (latency to pen) differences were found between the finely balanced and balanced conditions, but these were likely to be artefacts of the greater time and effort required to push through the weighted doors. No other behavioural and physiological measures were significantly different between the decision categories. We suggest that more information is needed on when best to monitor likely changes in arousal during decision-making and that future studies should consider decisions defined as difficult in other ways.

Understanding behavioral and physiological phenotypes of stress and anxiety in zebrafish.

PubMed

Egan, Rupert J; Bergner, Carisa L; Hart, Peter C; Cachat, Jonathan M; Canavello, Peter R; Elegante, Marco F; Elkhayat, Salem I; Bartels, Brett K; Tien, Anna K; Tien, David H; Mohnot, Sopan; Beeson, Esther; Glasgow, Eric; Amri, Hakima; Zukowska, Zofia; Kalueff, Allan V

2009-12-14

The zebrafish (Danio rerio) is emerging as a promising model organism for experimental studies of stress and anxiety. Here we further validate zebrafish models of stress by analyzing how environmental and pharmacological manipulations affect their behavioral and physiological phenotypes. Experimental manipulations included exposure to alarm pheromone, chronic exposure to fluoxetine, acute exposure to caffeine, as well as acute and chronic exposure to ethanol. Acute (but not chronic) alarm pheromone and acute caffeine produced robust anxiogenic effects, including reduced exploration, increased erratic movements and freezing behavior in zebrafish tested in the novel tank diving test. In contrast, ethanol and fluoxetine had robust anxiolytic effects, including increased exploration and reduced erratic movements. The behavior of several zebrafish strains was also quantified to ascertain differences in their behavioral profiles, revealing high-anxiety (leopard, albino) and low-anxiety (wild type) strains. We also used LocoScan (CleverSys Inc.) video-tracking tool to quantify anxiety-related behaviors in zebrafish, and dissect anxiety-related phenotypes from locomotor activity. Finally, we developed a simple and effective method of measuring zebrafish physiological stress responses (based on a human salivary cortisol assay), and showed that alterations in whole-body cortisol levels in zebrafish parallel behavioral indices of anxiety. Collectively, our results confirm zebrafish as a valid, reliable, and high-throughput model of stress and affective disorders.

Human reproductive issues in space

NASA Technical Reports Server (NTRS)

Santy, Patricia A.; Jennings, Richard T.

1992-01-01

A review of reproductive functioning in animal species studied during space flight demonstrated that most species were affected significantly by the absence of gravity and/or the presence of radiation. These two factors induced alterations in normal reproductive functioning independently of, as well as in combination with, each other. Based on animal models, several potential problem areas regarding human reproductive physiology and functioning in the space environment were identified. While there are no current space flight investigations, the animal studies suggest priorities for future research in human reproduction. Such studies will be critical for the successful colonization of the space frontier.

Affective assessment of computer users based on processing the pupil diameter signal.

PubMed

Ren, Peng; Barreto, Armando; Gao, Ying; Adjouadi, Malek

2011-01-01

Detecting affective changes of computer users is a current challenge in human-computer interaction which is being addressed with the help of biomedical engineering concepts. This article presents a new approach to recognize the affective state ("relaxation" vs. "stress") of a computer user from analysis of his/her pupil diameter variations caused by sympathetic activation. Wavelet denoising and Kalman filtering methods are first used to remove abrupt changes in the raw Pupil Diameter (PD) signal. Then three features are extracted from the preprocessed PD signal for the affective state classification. Finally, a random tree classifier is implemented, achieving an accuracy of 86.78%. In these experiments the Eye Blink Frequency (EBF), is also recorded and used for affective state classification, but the results show that the PD is a more promising physiological signal for affective assessment.

Measures of physiological stress: a transparent or opaque window into the status, management and conservation of species?

PubMed Central

Dantzer, Ben; Fletcher, Quinn E.; Boonstra, Rudy; Sheriff, Michael J.

2014-01-01

Conservation physiology proposes that measures of physiological stress (glucocorticoid levels) can be used to assess the status and future fate of natural populations. Increases in glucocorticoids may reflect a more challenging environment, suggesting that the influence of human activities on free-living animals could be quantified by measuring glucocorticoids. Biomedical studies suggest that chronic increases in glucocorticoids can have detrimental effects on survival and reproduction, which could influence the viability of populations. Here, we discuss the use of measurements of glucocorticoids in conservation physiology. We first provide an overview of the different methods to quantify glucocorticoids and their utility in conservation physiology. We then discuss five questions we think are essential for conservation physiologists to address. We highlight how intrinsic (e.g. sex, reproductive status, age, recent experiences) and ecological factors (e.g. predation, food availability, snowfall) can, by themselves or through their interactions with anthropogenic disturbances, affect the physiological stress response and mask any general patterns about the effects of anthropogenic disturbances on glucocorticoids. Using a meta-analysis, we show that anthropogenic disturbances are consistently associated with increased glucocorticoids regardless of the type of human disturbance. We also show that males may be more sensitive to anthropogenic disturbances than females and that faecal glucocorticoids, but not baseline plasma glucocorticoids, consistently increase in response to anthropogenic disturbances. Finally, we discuss how increases in glucocorticoids in free-living animals can sometimes enhance survival and reproduction. Unfortunately, our literature analysis indicates that this observation has not yet gained traction, and very few studies have shown that increases in glucocorticoid levels resulting from anthropogenic disturbances decrease survival or reproduction

Development of a physiologically based pharmacokinetic model for assessment of human exposure to bisphenol A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Xiaoxia, E-mail: xiaoxia.yang@fda.hhs.gov; Doerge, Daniel R.; Teeguarden, Justin G.

A previously developed physiologically based pharmacokinetic (PBPK) model for bisphenol A (BPA) in adult rhesus monkeys was modified to characterize the pharmacokinetics of BPA and its phase II conjugates in adult humans following oral ingestion. Coupled with in vitro studies on BPA metabolism in the liver and the small intestine, the PBPK model was parameterized using oral pharmacokinetic data with deuterated-BPA (d{sub 6}-BPA) delivered in cookies to adult humans after overnight fasting. The availability of the serum concentration time course of unconjugated d{sub 6}-BPA offered direct empirical evidence for the calibration of BPA model parameters. The recalibrated PBPK adult humanmore » model for BPA was then evaluated against published human pharmacokinetic studies with BPA. A hypothesis of decreased oral uptake was needed to account for the reduced peak levels observed in adult humans, where d{sub 6}-BPA was delivered in soup and food was provided prior to BPA ingestion, suggesting the potential impact of dosing vehicles and/or fasting on BPA disposition. With the incorporation of Monte Carlo analysis, the recalibrated adult human model was used to address the inter-individual variability in the internal dose metrics of BPA for the U.S. general population. Model-predicted peak BPA serum levels were in the range of pM, with 95% of human variability falling within an order of magnitude. This recalibrated PBPK model for BPA in adult humans provides a scientific basis for assessing human exposure to BPA that can serve to minimize uncertainties incurred during extrapolations across doses and species. - Highlights: • A PBPK model predicts the kinetics of bisphenol A (BPA) in adult humans. • Serum concentrations of aglycone BPA are available for model calibration. • Model predicted peak BPA serum levels for adult humans were in the range of pM. • Model predicted 95% of human variability fell within an order of magnitude.« less

Exposure of engineered nanomaterials to plants: Insights into the physiological and biochemical responses-A review.

PubMed

Zuverza-Mena, Nubia; Martínez-Fernández, Domingo; Du, Wenchao; Hernandez-Viezcas, Jose A; Bonilla-Bird, Nestor; López-Moreno, Martha L; Komárek, Michael; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

2017-01-01

Recent investigations show that carbon-based and metal-based engineered nanomaterials (ENMs), components of consumer goods and agricultural products, have the potential to build up in sediments and biosolid-amended agricultural soils. In addition, reports indicate that both carbon-based and metal-based ENMs affect plants differently at the physiological, biochemical, nutritional, and genetic levels. The toxicity threshold is species-dependent and responses to ENMs are driven by a series of factors including the nanomaterial characteristics and environmental conditions. Effects on the growth, physiological and biochemical traits, production and food quality, among others, have been reported. However, a complete understanding of the dynamics of interactions between plants and ENMs is not clear enough yet. This review presents recent publications on the physiological and biochemical effects that commercial carbon-based and metal-based ENMs have in terrestrial plants. This document focuses on crop plants because of their relevance in human nutrition and health. We have summarized the mechanisms of interaction between plants and ENMs as well as identified gaps in knowledge for future investigations. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Cardiovascular function and basics of physiology in microgravity.

PubMed

Aubert, André E; Beckers, Frank; Verheyden, Bart

2005-04-01

Space exploration is a dream of mankind. However, this intriguing environment is not without risks. Life, and the human body, has developed all over evolution in the constant presence of gravity, especially from the moment on when living creatures left the ocean. When this gravitational force is no longer acting on the body, drastic changes occur. Some of these changes occur immediately, others progress only slowly. In the past 40 years of human space flight (first orbital flight by Yuri Gagarin on 12 April, 1961) several hazards for the human body have been identified. Bone mineral density is lost, muscle atrophy and cardiovascular deconditioning occur; pulmonary function, fluid regulating systems of the body, the sensory and the balance system are all disturbed by the lack of gravity. These changes in human physiology have to be reversed again when astronauts return to earth. This can cause adaptation problems, especially after long-duration space flights. Also the reaction of human physiology to radiation in space poses a huge risk at this moment. In this review the accent will be on cardiovascular function in space: how normal function is modified to reach a new equilibrium in space after short- and long-duration exposure to microgravity. In order to make long-duration space flight possible the mechanisms of this physiological adaptation must be understood to full extent. Only with this knowledge, effective countermeasures can be developed.

Complexity analysis of human physiological signals based on case studies

NASA Astrophysics Data System (ADS)

Angelova, Maia; Holloway, Philip; Ellis, Jason

2015-04-01

This work focuses on methods for investigation of physiological time series based on complexity analysis. It is a part of a wider programme to determine non-invasive markers for healthy ageing. We consider two case studies investigated with actigraphy: (a) sleep and alternations with insomnia, and (b) ageing effects on mobility patterns. We illustrate, using these case studies, the application of fractal analysis to the investigation of regulation patterns and control, and change of physiological function. In the first case study, fractal analysis techniques were implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia in comparison with healthy controls. The aim was to investigate if complexity analysis can detect the onset of adverse health-related events. The subjects with acute insomnia displayed significantly higher levels of complexity, possibly a result of too much activity in the underlying regulatory systems. The second case study considered mobility patterns during night time and their variations with age. It showed that complexity metrics can identify change in physiological function with ageing. Both studies demonstrated that complexity analysis can be used to investigate markers of health, disease and healthy ageing.

Physiological consequences of rapid or prolonged aircraft decompression: evaluation using a human respiratory model.

PubMed

Wolf, Matthew

2014-04-01

Aircraft passengers and crew may be subjected to rapid or prolonged decompression to high cabin altitude when an aircraft develops a hole in the fuselage. The accepted measure of neurological damage due to the hypobaric hypoxia produced is the subjective 'time of useful consciousness' (TUC) measure, which is appropriate for pilots and crew who perform their given tasks, however, TUC is measured under conditions different than the decompression scenarios that passengers undergo in today's aircraft. Ernsting proposed that prolonged exposure to alveolar O2 pressures less than 30 mmHg (P30) causes neurological damage. The current study proposes that a critical value of arterial O2 saturation of 70% (S70) can be used in place of P30 and that this physiological measure is more suited for determination of hypobaric hypoxia in passengers. The study shows the equivalence of model-predicted P30 and S70 values in the Ernsting-decompression scenarios. The model is also used to predict values of these physiological measures in actual aircraft-decompression scenarios. The model can be used by others to quantitatively predict the degree of hypobaric hypoxia for virtually any kind of decompression scenario, including those where supplemental O2 is used. Use of this tool avoids the prohibitive costs of human-subject testing for new aircraft and the potential danger inherent in such tests.

Vegetation physiology controls continental water cycle responses to climate change

NASA Astrophysics Data System (ADS)

Lemordant, L. A.; Swann, A. L. S.; Cook, B.; Scheff, J.; Gentine, P.

2017-12-01

Abstract per se:Predicting how climate change will affect the hydrologic cycle is of utmost importance for ecological systems and for human life and activities. A typical perspective is that global warming will cause an intensification of the mean state, the so-called "dry gets drier, wet gets wetter" paradigm. While this result is robust over the oceans, recent works suggest it may be less appropriate for terrestrial regions. Using Earth System Models (ESMs) with decoupled surface (vegetation physiology, PHYS) and atmospheric (radiative, ATMO) CO2 responses, we show that the CO2 physiological response dominates the change in the continental hydrologic cycle compared to radiative and precipitation changes due to increased atmospheric CO2, counter to previous assumptions. Using multiple linear regression analysis, we estimate the individual contribution of each of the three main drivers, precipitation, radiation and physiological CO2 forcing (see attached figure). Our analysis reveals that physiological effects dominate changes for 3 key indicators of dryness and/or vegetation stress (namely LAI, P-ET and EF) over the largest fraction of the globe, except for soil moisture which exhibits a more complex response. This highlights the key role of vegetation in controlling future terrestrial hydrologic response.Legend of the Figure attached:Decomposition along the three main drivers of LAI (a), P-ET (b), EF (c) in the control run. Green quantifies the effect of the vegetation physiology based on the run PHYS; red and blue quantify the contribution of, respectively, net radiation and precipitation, based on multiple linear regression in ATMO. Pie charts show for each variable the fraction (labelled in %) of land under the main influence (more than 50% of the changes is attributed to this driver) of one the three main drivers (green for grid points dominated by vegetation physiology, red for grid points dominated by net radiation, and blue for grid points dominated by the

The Human Centrifuge

NASA Astrophysics Data System (ADS)

van Loon, Jack J. W. A.

2009-01-01

Life on Earth has developed at unit gravity, 9.81 m/s2, which was a major factor especially when vertebrates emerged from water onto land in the late Devonian, some 375 million years ago. But how would nature have evolved on a larger planet? We are able to address this question simply in experiments using centrifuges. Based on these studies we have gained valuable insights in the physiological process in plants and animals. They adapt to a new steady state suitable for the high-g environments applied. Information on mammalian adaptations to hyper-g is interesting or may be even vital for human space exploration programs. It has been shown in long duration animal hypergravity studies, ranging from snails, rats to primates, that various structures like muscles, bones, neuro-vestibular, or the cardio-vascular system are affected. However, humans have never been exposed to a hyper-g environment for long durations. Centrifuge studies involving humans are mostly in the order of hours. The current work on human centrifuges are all focused on short arm systems to apply short periods of artificial gravity in support of long duration space missions in ISS or to Mars. In this paper we will address the possible usefulness of a large human centrifuge on Earth. In such a centrifuge a group of humans can be exposed to hypergravity for, in principle, an unlimited period of time like living on a larger planet. The input from a survey under scientists working in the field of gravitational physiology, but also other disciplines, will be discussed.

Using Stimulation of the Diving Reflex in Humans to Teach Integrative Physiology

ERIC Educational Resources Information Center

Choate, Julia K.; Denton, Kate M.; Evans, Roger G.; Hodgson, Yvonne

2014-01-01

During underwater submersion, the body responds by conserving O[subscript 2] and prioritizing blood flow to the brain and heart. These physiological adjustments, which involve the nervous, cardiovascular, and respiratory systems, are known as the diving response and provide an ideal example of integrative physiology. The diving reflex can be…

Prediction of Fetal Darunavir Exposure by Integrating Human Ex-Vivo Placental Transfer and Physiologically Based Pharmacokinetic Modeling.

PubMed

Schalkwijk, Stein; Buaben, Aaron O; Freriksen, Jolien J M; Colbers, Angela P; Burger, David M; Greupink, Rick; Russel, Frans G M

2017-07-25

Fetal antiretroviral exposure is usually derived from the cord-to-maternal concentration ratio. This static parameter does not provide information on the pharmacokinetics in utero, limiting the assessment of a fetal exposure-effect relationship. The aim of this study was to incorporate placental transfer into a pregnancy physiologically based pharmacokinetic model to simulate and evaluate fetal darunavir exposure at term. An existing and validated pregnancy physiologically based pharmacokinetic model of maternal darunavir/ritonavir exposure was extended with a feto-placental unit. To parameterize the model, we determined maternal-to-fetal and fetal-to-maternal darunavir/ritonavir placental clearance with an ex-vivo human cotyledon perfusion model. Simulated maternal and fetal pharmacokinetic profiles were compared with observed clinical data to qualify the model for simulation. Next, population fetal pharmacokinetic profiles were simulated for different maternal darunavir/ritonavir dosing regimens. An average (±standard deviation) maternal-to-fetal cotyledon clearance of 0.91 ± 0.11 mL/min and fetal-to-maternal clearance of 1.6 ± 0.3 mL/min was determined (n = 6 perfusions). Scaled placental transfer was integrated into the pregnancy physiologically based pharmacokinetic model. For darunavir 600/100 mg twice a day, the predicted fetal maximum plasma concentration, trough concentration, time to maximum plasma concentration, and half-life were 1.1, 0.57 mg/L, 3, and 21 h, respectively. This indicates that the fetal population trough concentration is higher or around the half-maximal effective darunavir concentration for a resistant virus (0.55 mg/L). The results indicate that the population fetal exposure after oral maternal darunavir dosing is therapeutic and this may provide benefits to the prevention of mother-to-child transmission of human immunodeficiency virus. Moreover, this integrated approach provides a tool to prevent fetal toxicity or

Low concentrations of Bisphenol A and para-Nonylphenol affect extravillous pathway of human trophoblast cells.

PubMed

Spagnoletti, Antonella; Paulesu, Luana; Mannelli, Chiara; Ermini, Leonardo; Romagnoli, Roberta; Cintorino, Marcella; Ietta, Francesca

2015-09-05

Bisphenol A (BPA) and para-Nonylphenol (p-NP) are chemicals of industrial origin which may influence human reproductive health. The effects of these substances in the prenatal life is an important topic that is receiving greater attention in the developed countries. In this study, human trophoblast cells HTR-8/SVneo were exposed to BPA and p-NP (1 × 10(-15), 1 × 10(-13), 1 × 10(-11), 1 × 10(-9) and 1 × 10(-7) M) and incubated for 24, 48 and/or 72 h then, examined for the main physiological processes which characterize the extravillous trophoblast. Cell proliferation showed no changes while the processes of cell migration and invasion were both reduced by BPA and p-NP. For each chemical, the activity was higher at lower concentrations with a maximum activity between 1 × 10(-13) and 1 × 10(-11) M (p < 0.05 for 1 × 10(-9) and p < 0.001 for 1 × 10(-11) M). Co-culture studies with human umbilical cord endothelial cells (HUVEC) revealed that trophoblast/endothelial interaction was significantly reduced by p-NP at 1 × 10(-11) M. Moreover, both chemicals were inducing differentiation of HTR-8/SVneo toward polyploidy by the process of endoreduplication. The estrogen-receptor antagonist ICI significantly reduced p-NP action, while it had no effect on BPA treated cells. In conclusion, p-NP and BPA act on trophoblast cells altering key physiological processes in placenta development. The exact mechanism of action of the chemicals in human trophoblast still needs to be clarified. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Short-term exposure to mobile phone base station signals does not affect cognitive functioning or physiological measures in individuals who report sensitivity to electromagnetic fields and controls.

PubMed

Eltiti, Stacy; Wallace, Denise; Ridgewell, Anna; Zougkou, Konstantina; Russo, Riccardo; Sepulveda, Francisco; Fox, Elaine

2009-10-01

Individuals who report sensitivity to electromagnetic fields often report cognitive impairments that they believe are due to exposure to mobile phone technology. Previous research in this area has revealed mixed results, however, with the majority of research only testing control individuals. Two studies using control and self-reported sensitive participants found inconsistent effects of mobile phone base stations on cognitive functioning. The aim of the present study was to clarify whether short-term (50 min) exposure at 10 mW/m(2) to typical Global System for Mobile Communication (GSM) and Universal Mobile Telecommunications System (UMTS) base station signals affects attention, memory, and physiological endpoints in sensitive and control participants. Data from 44 sensitive and 44 matched-control participants who performed the digit symbol substitution task (DSST), digit span task (DS), and a mental arithmetic task (MA), while being exposed to GSM, UMTS, and sham signals under double-blind conditions were analyzed. Overall, cognitive functioning was not affected by short-term exposure to either GSM or UMTS signals in the current study. Nor did exposure affect the physiological measurements of blood volume pulse (BVP), heart rate (HR), and skin conductance (SC) that were taken while participants performed the cognitive tasks.

[Pain in humans: experimental facts and hypotheses].

PubMed

Cesaro, P

1994-09-15

The description of painful phenomena in humans has to take into account its different components: sensory component (relevant to nociception), affective and emotional components. Nociceptor's (physiology is best understood with electrophysiological and neurochemical methods allowing a clear description of hyperalgesia, with its peripheral and spinal mechanisms. A functional model is partly available to explain allodynia, spontaneous burning pain and lightning pain, the three main consequences following deafferentation. At the thalamo-cortical level, one can describe nociceptive pathways and other pathways or neuronal networks involved in the affective and emotional components of pain.

Human footprint affects US carbon balance more than climate change

USGS Publications Warehouse

Bachelet, Dominique; Ferschweiler, Ken; Sheehan, Tim; Baker, Barry; Sleeter, Benjamin M.; Zhu, Zhiliang

2017-01-01

The MC2 model projects an overall increase in carbon capture in conterminous United States during the 21st century while also simulating a rise in fire causing much carbon loss. Carbon sequestration in soils is critical to prevent carbon losses from future disturbances, and we show that natural ecosystems store more carbon belowground than managed systems do. Natural and human-caused disturbances affect soil processes that shape ecosystem recovery and competitive interactions between native, exotics, and climate refugees. Tomorrow's carbon budgets will depend on how land use, natural disturbances, and climate variability will interact and affect the balance between carbon capture and release.

Rhythmic entrainment as a musical affect induction mechanism.

PubMed

J Trost, W; Labbé, C; Grandjean, D

2017-02-01

One especially important feature of metrical music is that it contains periodicities that listeners' bodily rhythms can adapt to. Recent psychological frameworks have introduced the notion of rhythmic entrainment, among other mechanisms, as an emotion induction principle. In this review paper, we discuss rhythmic entrainment as an affect induction mechanism by differentiating four levels of entrainment in humans-perceptual, autonomic physiological, motor, and social-all of which could contribute to a subjective feeling component. We review the theoretical and empirical literature on rhythmic entrainment to music that supports the existence of these different levels of entrainment by describing the phenomena and characterizing the associated underlying brain processes. The goal of this review is to present the theoretical implications and empirical findings about rhythmic entrainment as an important principle at the basis of affect induction via music, since it rests upon the temporal dimension of music, which is a specificity of music as an affective stimulus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Human cold stress of strong local-wind "Hijikawa-arashi" in Japan, based on the UTCI index and thermo-physiological responses.

PubMed

Ohashi, Yukitaka; Katsuta, Takumi; Tani, Haruka; Okabayashi, Taiki; Miyahara, Satoshi; Miyashita, Ryoji

2018-03-30

We investigated the cold stress caused by a strong local wind called "Hijikawa-arashi," through in situ vital measurements and the Universal Thermal Climate Index (UTCI). This wind is a very interesting winter phenomenon, localized in an area within 1 km of the seashore in Ozu City, Ehime Prefecture in Japan. When a strong Hijikawa-arashi (HA) occurred at 14-15 m s -1 , the UTCI decreased to - 30 °C along the bridge where commuting residents are the most exposed to strong and cold winds. On the bridge, most participants in our experiment felt "very cold" or "extremely cold." The UTCI of HA can be predicted from a multiple regression equation using wind speed and air temperature. The cold HA wind is also harmful to human thermo-physiological responses. It leads to higher blood pressure and increased heart rate, both of which act as cardiovascular stress triggers. Increases of 6-10 mmHg and 3-6 bpm for every 10 °C reduction in UTCI were seen on all observational days, including HA and non-HA days. In fact, the participants' body skin temperatures decreased by approximately 1.2 to 1.7 °C for every 10 °C reduction in UTCI. Thus, the UTCI variation due to the HA outbreak corresponded well with the cold sensation and thermo-physiological responses in humans. This result suggests that daily UTCI monitoring enables the prediction of thermo-physiological responses to the HA cold stress.

[Role of some psycho-physiological factors on driving safety].

PubMed

Bergomi, M; Vivoli, G; Rovesti, S; Bussetti, P; Ferrari, A; Vivoli, R

2010-01-01

Within a research project on the role played by human factors on road accidents, the aim of the present study is to evaluate, in young adults, the relationships between driver behaviour and personality factors as well as to assess the neuroendocrine correlates of psychological and behavioural factors investigated. Another aim is to estimate in what measure the performance levels are affected by demographic, psychological and chronobiological variables. It has been found a positive relation between highway code violations, extroversion trait of personality and Sensation Seeking scores, so confirming that this component of personality can affect risky behaviour. Furthermore the subjects more oriented to morningness chronotype were found to be prone to adopt safe driving behaviour. Regarding the relations of the neuroendocrine parameters and driving behaviour a positive correlation was observed between dopamine levels and frequency of driving violations while a negative relationship was found between adrenaline levels and frequency of driving errors. In conclusion the identification of psycho-physiological variables related to driving risky behaviour might be a useful instrument to design traffic safety programs tailored to high risk subjects.

Contactless physiological signals extraction based on skin color magnification

NASA Astrophysics Data System (ADS)

Suh, Kun Ha; Lee, Eui Chul

2017-11-01

Although the human visual system is not sufficiently sensitive to perceive blood circulation, blood flow caused by cardiac activity makes slight changes on human skin surfaces. With advances in imaging technology, it has become possible to capture these changes through digital cameras. However, it is difficult to obtain clear physiological signals from such changes due to its fineness and noise factors, such as motion artifacts and camera sensing disturbances. We propose a method for extracting physiological signals with improved quality from skin colored-videos recorded with a remote RGB camera. The results showed that our skin color magnification method reveals the hidden physiological components remarkably in the time-series signal. A Korea Food and Drug Administration-approved heart rate monitor was used for verifying the resulting signal synchronized with the actual cardiac pulse, and comparisons of signal peaks showed correlation coefficients of almost 1.0. In particular, our method can be an effective preprocessing before applying additional postfiltering techniques to improve accuracy in image-based physiological signal extractions.

Jets over Labrador and Quebec: noise effects on human health.

PubMed Central

Rosenberg, J

1991-01-01

OBJECTIVE: To determine whether the noise from low-level flights over Labrador and Quebec is harmful to human health. DATA SOURCE AND SELECTION: Search of MEDLINE for articles on the effect of noise, particularly impulse noise associated with low-level flights, and a search of the references from identified articles. DATA SYNTHESIS: The noise levels from low-level flights could affect hearing acuity. However, the more important consequences appear to be stress-mediated physiologic effects, especially cardiovascular ones, and psychologic distress, particularly in children. Subjective perception of control over the noise has been found to mitigate some physiologic effects. CONCLUSION: There is sufficient evidence to show that the noise from low-level flights is harmful to human health. PMID:2007238

Oocyte cryopreservation and in vitro culture affect calcium signalling during human fertilization.

PubMed

Nikiforaki, D; Vanden Meerschaut, F; Qian, C; De Croo, I; Lu, Y; Deroo, T; Van den Abbeel, E; Heindryckx, B; De Sutter, P

2014-01-01

What are the precise patterns of calcium oscillations during the fertilization of human oocytes matured either in vivo or in vitro or aged in vitro and what is the effect of cryopreservation? Human oocytes matured in vivo exhibit a specific pattern of calcium oscillations, which is affected by in vitro maturation, in vitro ageing and cryopreservation. Oscillations in cytoplasmic calcium concentration are crucial for oocyte activation and further embryonic development. While several studies have described in detail the calcium oscillation pattern during fertilization in animal models, studies with human oocytes are scarce. This was a laboratory-based study using human MII oocytes matured in vivo or in vitro either fresh or after cryopreservation with slow freezing or vitrification. Altogether, 205 human oocytes were included in the analysis. In vivo and in vitro matured human oocytes were used for this research either fresh or following vitrification/warming (V/W) and slow freezing/thawing (F/T). Human oocytes were obtained following written informed consent from patients undergoing ovarian hyperstimulation. For the calcium pattern analysis, oocytes were loaded with the ratiometric calcium indicator fluorescent dye Fura-2. Following ICSI using sperm from a single donor, intracellular calcium was measured for 16 h at 37°C under 6% CO(2). The calcium oscillation parameters were calculated for all intact oocytes that showed calcium oscillations and were analyzed using the Mann-Whitney U-test. Human in vivo MII oocytes display a specific pattern of calcium oscillations following ICSI. This pattern is significantly affected by in vitro ageing, with the calcium oscillations occurring over a longer period of time and with a lower frequency, shorter duration and higher amplitude (P < 0.05). In vitro matured oocytes from the GV and MI stage exhibit a different pattern of calcium oscillations with calcium transients being of lower frequency and shorter duration compared with

Ethyl nitrite is produced in the human stomach from dietary nitrate and ethanol, releasing nitric oxide at physiological pH: potential impact on gastric motility.

PubMed

Rocha, Bárbara S; Gago, Bruno; Barbosa, Rui M; Cavaleiro, Carlos; Laranjinha, João

2015-05-01

Nitric oxide ((∙)NO), a ubiquitous molecule involved in a plethora of signaling pathways, is produced from dietary nitrate in the gut through the so-called nitrate-nitrite-NO pathway. In the stomach, nitrite derived from dietary nitrate triggers a network of chemical reactions targeting endogenous and exogenous biomolecules, thereby producing new compounds with physiological activity. The aim of this study was to ascertain whether compounds with physiological relevance are produced in the stomach upon consumption of nitrate- and ethanol-rich foods. Human volunteers consumed a serving of lettuce (source of nitrate) and alcoholic beverages (source of ethanol). After 15 min, samples of the gastric headspace were collected and ethyl nitrite was identified by GC-MS. Wistar rats were used to study the impact of ethyl nitrite on gastric smooth muscle relaxation at physiological pH. Nitrogen oxides, produced from nitrite in the stomach, induce nitrosation of ethanol from alcoholic beverages in the human stomach yielding ethyl nitrite. Ethyl nitrite, a potent vasodilator, is produced in vivo upon the consumption of lettuce with either red wine or whisky. Moreover, at physiological pH, ethyl nitrite induces gastric smooth muscle relaxation through a cGMP-dependent pathway. Overall, these results suggest that ethyl nitrite is produced in the gastric lumen and releases (∙)NO at physiological pH, which ultimately may have an impact on gastric motility. Systemic effects may also be expected if ethyl nitrite diffuses through the gastric mucosa reaching blood vessels, therefore operating as a (∙)NO carrier throughout the body. These data pinpoint posttranslational modifications as an underappreciated mechanism for the production of novel molecules with physiological impact locally in the gut and highlight the notion that diet may fuel compounds with the potential to modulate gastrointestinal welfare. Copyright © 2015 Elsevier Inc. All rights reserved.

Cue competition affects temporal dynamics of edge-assignment in human visual cortex.

PubMed

Brooks, Joseph L; Palmer, Stephen E

2011-03-01

Edge-assignment determines the perception of relative depth across an edge and the shape of the closer side. Many cues determine edge-assignment, but relatively little is known about the neural mechanisms involved in combining these cues. Here, we manipulated extremal edge and attention cues to bias edge-assignment such that these two cues either cooperated or competed. To index their neural representations, we flickered figure and ground regions at different frequencies and measured the corresponding steady-state visual-evoked potentials (SSVEPs). Figural regions had stronger SSVEP responses than ground regions, independent of whether they were attended or unattended. In addition, competition and cooperation between the two edge-assignment cues significantly affected the temporal dynamics of edge-assignment processes. The figural SSVEP response peaked earlier when the cues causing it cooperated than when they competed, but sustained edge-assignment effects were equivalent for cooperating and competing cues, consistent with a winner-take-all outcome. These results provide physiological evidence that figure-ground organization involves competitive processes that can affect the latency of figural assignment.