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 across all systems, examining the relationship of corticolimbic reactivity and negative affect, and sex differences in emotion regulation processes. PMID:22281210

Hormones and the hippocampus.

PubMed

Lathe, R

2001-05-01

Hippocampal lesions produce memory deficits, but the exact function of the hippocampus remains obscure. Evidence is presented that its role in memory may be ancillary to physiological regulation. Molecular studies demonstrate that the hippocampus is a primary target for ligands that reflect body physiology, including ion balance and blood pressure, immunity, pain, reproductive status, satiety and stress. Hippocampal receptors are functional, probably accessible to their ligands, and mediate physiological and cognitive changes. This argues that an early role of the hippocampus may have been in sensing soluble molecules (termed here 'enteroception') in blood and cerebrospinal fluid, perhaps reflecting a common evolutionary origin with the olfactory system ('exteroception'). Functionally, hippocampal enteroception may reflect feedback control; evidence is reviewed that the hippocampus modulates body physiology, including the activity of the hypothalamus-pituitary-adrenal axis, blood pressure, immunity, and reproductive function. It is suggested that the hippocampus operates, in parallel with the amygdala, to modulate body physiology in response to cognitive stimuli. Hippocampal outputs are predominantly inhibitory on downstream neuroendocrine activity; increased synaptic efficacy in the hippocampus (e.g. long-term potentiation) could facilitate throughput inhibition. This may have implications for the role of the hippocampus and long-term potentiation in memory.

Innovative Strategies for Teaching Anatomy and Physiology.

ERIC Educational Resources Information Center

Ritt, Laura; Stewart, Barbara

1996-01-01

Describes the development of new teaching strategies in an anatomy and physiology laboratory at Burlington County College (New Jersey) based on laser disc technology, computers with multimedia capabilities, and appropriate software. Lab activities are described and results of a survey of former students are reported, including a comparison of lab…

Obstructive sleep apnea.

PubMed

White, David P; Younes, Magdy K

2012-10-01

Obstructive sleep apnea (OSA) is a common disorder characterized by repetitive collapse of the pharyngeal airway during sleep. Control of pharyngeal patency is a complex process relating primarily to basic anatomy and the activity of many pharyngeal dilator muscles. The control of these muscles is regulated by a number of processes including respiratory drive, negative pressure reflexes, and state (sleep) effects. In general, patients with OSA have an anatomically small airway the patency of which is maintained during wakefulness by reflex-driven augmented dilator muscle activation. At sleep onset, muscle activity falls, thereby compromising the upper airway. However, recent data suggest that the mechanism of OSA differs substantially among patients, with variable contributions from several physiologic characteristics including, among others: level of upper airway dilator muscle activation required to open the airway, increase in chemical drive required to recruit the pharyngeal muscles, chemical control loop gain, and arousal threshold. Thus, the cause of sleep apnea likely varies substantially between patients. Other physiologic mechanisms likely contributing to OSA pathogenesis include falling lung volume during sleep, shifts in blood volume from peripheral tissues to the neck, and airway edema. Apnea severity may progress over time, likely due to weight gain, muscle/nerve injury, aging effects on airway anatomy/collapsibility, and changes in ventilatory control stability. © 2012 American Physiological Society

An investigation into the relationship between age and physiological function in highly active older adults.

PubMed

Pollock, Ross D; Carter, Scott; Velloso, Cristiana P; Duggal, Niharika A; Lord, Janet M; Lazarus, Norman R; Harridge, Stephen D R

2015-02-01

The relationship between age and physiological function remains poorly defined and there are no physiological markers that can be used to reliably predict the age of an individual. This could be due to a variety of confounding genetic and lifestyle factors, and in particular to ill-defined and low levels of physical activity. This study assessed the relationship between age and a diverse range of physiological functions in a cohort of highly active older individuals (cyclists) aged 55-79 years in whom the effects of lifestyle factors would be ameliorated. Significant associations between age and function were observed for many functions. V̇O2max was most closely associated with age, but even here the variance in age for any given level was high, precluding the clear identification of the age of any individual. The data suggest that the relationship between human ageing and physiological function is highly individualistic and modified by inactivity. Despite extensive research, the relationship between age and physiological function remains poorly characterised and there are currently no reliable markers of human ageing. This is probably due to a number of confounding factors, particularly in studies of a cross-sectional nature. These include inter-subject genetic variation, as well as inter-generational differences in nutrition, healthcare and insufficient levels of physical activity as well as other environmental factors. We have studied a cohort of highly and homogeneously active older male (n = 84) and female (n = 41) cyclists aged 55-79 years who it is proposed represent a model for the study of human ageing free from the majority of confounding factors, especially inactivity. The aim of the study was to identify physiological markers of ageing by assessing the relationship between function and age across a wide range of indices. Each participant underwent a detailed physiological profiling which included measures of cardiovascular, respiratory, neuromuscular, metabolic, endocrine and cognitive functions, bone strength, and health and well-being. Significant associations between age and function were observed for many functions. The maximal rate of oxygen consumption (V̇O2max) showed the closest association with age (r = -0.443 to -0.664; P < 0.001), but even here the variance in age for any given level was high, precluding the clear identification of the age of any individual. The results of this cross-sectional study suggest that even when many confounding variables are removed the relationship between function and healthy ageing is complex and likely to be highly individualistic and that physical activity levels must be taken into account in ageing studies. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

Physiological Effects of Nature Therapy: A Review of the Research in Japan.

PubMed

Song, Chorong; Ikei, Harumi; Miyazaki, Yoshifumi

2016-08-03

Humans have evolved into what they are today after the passage of 6-7 million years. If we define the beginning of urbanization as the rise of the industrial revolution, less than 0.01% of our species' history has been spent in modern surroundings. Humans have spent over 99.99% of their time living in the natural environment. The gap between the natural setting, for which our physiological functions are adapted, and the highly urbanized and artificial setting that we inhabit is a contributing cause of the "stress state" in modern people. In recent years, scientific evidence supporting the physiological effects of relaxation caused by natural stimuli has accumulated. This review aimed to objectively demonstrate the physiological effects of nature therapy. We have reviewed research in Japan related to the following: (1) the physiological effects of nature therapy, including those of forests, urban green space, plants, and wooden material and (2) the analyses of individual differences that arise therein. The search was conducted in the PubMed database using various keywords. We applied our inclusion/exclusion criteria and reviewed 52 articles. Scientific data assessing physiological indicators, such as brain activity, autonomic nervous activity, endocrine activity, and immune activity, are accumulating from field and laboratory experiments. We believe that nature therapy will play an increasingly important role in preventive medicine in the future.

The heart of the story: peripheral physiology during narrative exposure predicts charitable giving.

PubMed

Barraza, Jorge A; Alexander, Veronika; Beavin, Laura E; Terris, Elizabeth T; Zak, Paul J

2015-02-01

Emotionally laden narratives are often used as persuasive appeals by charitable organizations. Physiological responses to a narrative may explain why some people respond to an appeal while others do not. In this study we tested whether autonomic and hormonal activity during a narrative predict subsequent narrative influence via charitable giving. Participants viewed a brief story of a father's experience with his 2-year-old son who has terminal cancer. After the story, participants were presented with an opportunity to donate some of their study earnings to a related charity. Measures derived from cardiac and electrodermal activity, including HF-HRV, significantly predicted donor status. Time-series GARCH models of physiology during the narrative further differentiated donors from non-donors. Moreover, cardiac activity and experienced concern were found to covary from moment-to-moment across the narrative. Our findings indicate that the physiological response to a stimulus, herein a narrative, can predict influence as indexed by stimulus-related behavior. Copyright © 2015 Elsevier B.V. All rights reserved.

Children’s Patterns of Emotional Reactivity to Conflict as Explanatory Mechanisms in Links Between Interpartner Aggression and Child Physiological Functioning

PubMed Central

Davies, Patrick T.; Sturge-Apple, Melissa L.; Cicchetti, Dante; Manning, Liviah G.; Zale, Emily

2009-01-01

Background This paper examined children’s fearful, sad, and angry reactivity to interparental conflict as mediators of associations between their exposure to interparental aggression and physiological functioning. Methods Participants included 200 toddlers and their mothers. Assessments of interparental aggression and children’s emotional reactivity were derived from maternal surveys and a semi-structured interview. Cortisol levels and cardiac indices of sympathetic nervous system (SNS) and parasympathetic nervous system (PNS) activity were used to assess toddler physiological functioning. Results Results indicated that toddler exposure to interparental aggression was associated with greater cortisol levels and PNS activity and diminished SNS activity. Toddler angry emotional reactivity mediated associations between interparental aggression and cortisol and PNS functioning. Fearful emotional reactivity was a mediator of the link between interparental aggression and SNS functioning. Conclusions The results are interpreted within conceptualizations of how exposure and reactivity to family risk organizing individual differences in physiological functioning. PMID:19744183

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.

Hypoxia decreases creatine uptake in cardiomyocytes, while creatine supplementation enhances HIF activation.

PubMed

Santacruz, Lucia; Arciniegas, Antonio Jose Luis; Darrabie, Marcus; Mantilla, Jose G; Baron, Rebecca M; Bowles, Dawn E; Mishra, Rajashree; Jacobs, Danny O

2017-08-01

Creatine (Cr), phosphocreatine (PCr), and creatine kinases (CK) comprise an energy shuttle linking ATP production in mitochondria with cellular consumption sites. Myocytes cannot synthesize Cr: these cells depend on uptake across the cell membrane by a specialized creatine transporter (CrT) to maintain intracellular Cr levels. Hypoxia interferes with energy metabolism, including the activity of the creatine energy shuttle, and therefore affects intracellular ATP and PCr levels. Here, we report that exposing cultured cardiomyocytes to low oxygen levels rapidly diminishes Cr transport by decreasing V max and K m Pharmacological activation of AMP-activated kinase (AMPK) abrogated the reduction in Cr transport caused by hypoxia. Cr supplementation increases ATP and PCr content in cardiomyocytes subjected to hypoxia, while also significantly augmenting the cellular adaptive response to hypoxia mediated by HIF-1 activation. Our results indicate that: (1) hypoxia reduces Cr transport in cardiomyocytes in culture, (2) the cytoprotective effects of Cr supplementation are related to enhanced adaptive physiological responses to hypoxia mediated by HIF-1, and (3) Cr supplementation increases the cellular ATP and PCr content in RNCMs exposed to hypoxia. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Physiological integration enhanced the tolerance of Cynodon dactylon to flooding.

PubMed

Li, Z J; Fan, D Y; Chen, F Q; Yuan, Q Y; Chow, W S; Xie, Z Q

2015-03-01

Many flooding-tolerant species are clonal plants; however, the effects of physiological integration on plant responses to flooding have received limited attention. We hypothesise that flooding can trigger changes in metabolism of carbohydrates and ROS (reactive oxygen species) in clonal plants, and that physiological integration can ameliorate the adverse effects of stress, subsequently restoring the growth of flooded ramets. In the present study, we conducted a factorial experiment combining flooding to apical ramets and stolon severing (preventing physiological integration) between apical and basal ramets of Cynodon dactylon, which is a stoloniferous perennial grass with considerable flooding tolerance. Flooding-induced responses including decreased root biomass, accumulation of soluble sugar and starch, as well as increased activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) in apical ramets. Physiological integration relieved growth inhibition, carbohydrate accumulation and induction of antioxidant enzyme activity in stressed ramets, as expected, without any observable cost in unstressed ramets. We speculate that relief of flooding stress in clonal plants may rely on oxidising power and electron acceptors transferred between ramets through physiological integration. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Predictive Physiological Anticipation Preceding Seemingly Unpredictable Stimuli: A Meta-Analysis

PubMed Central

Mossbridge, Julia; Tressoldi, Patrizio; Utts, Jessica

2012-01-01

This meta-analysis of 26 reports published between 1978 and 2010 tests an unusual hypothesis: for stimuli of two or more types that are presented in an order designed to be unpredictable and that produce different post-stimulus physiological activity, the direction of pre-stimulus physiological activity reflects the direction of post-stimulus physiological activity, resulting in an unexplained anticipatory effect. The reports we examined used one of two paradigms: (1) randomly ordered presentations of arousing vs. neutral stimuli, or (2) guessing tasks with feedback (correct vs. incorrect). Dependent variables included: electrodermal activity, heart rate, blood volume, pupil dilation, electroencephalographic activity, and blood oxygenation level dependent (BOLD) activity. To avoid including data hand-picked from multiple different analyses, no post hoc experiments were considered. The results reveal a significant overall effect with a small effect size [fixed effect: overall ES = 0.21, 95% CI = 0.15–0.27, z = 6.9, p < 2.7 × 10−12; random effects: overall (weighted) ES = 0.21, 95% CI = 0.13–0.29, z = 5.3, p < 5.7 × 10−8]. Higher quality experiments produced a quantitatively larger effect size and a greater level of significance than lower quality studies. The number of contrary unpublished reports that would be necessary to reduce the level of significance to chance (p > 0.05) was conservatively calculated to be 87 reports. We explore alternative explanations and examine the potential linkage between this unexplained anticipatory activity and other results demonstrating meaningful pre-stimulus activity preceding behaviorally relevant events. We conclude that to further examine this currently unexplained anticipatory activity, multiple replications arising from different laboratories using the same methods are necessary. The cause of this anticipatory activity, which undoubtedly lies within the realm of natural physical processes (as opposed to supernatural or paranormal ones), remains to be determined. PMID:23109927

The role of non-rainfall water on physiological activation in desert biological soil crusts

NASA Astrophysics Data System (ADS)

Zheng, Jiaoli; Peng, Chengrong; Li, Hua; Li, Shuangshuang; Huang, Shun; Hu, Yao; Zhang, Jinli; Li, Dunhai

2018-01-01

Non-rainfall water (NRW, e.g. fog and dew), in addition to rainfall and snowfall, are considered important water inputs to drylands. At the same time, biological soil crusts (BSCs) are important components of drylands. However, little information is available regarding the effect of NRW inputs on BSC activation. In this study, the effects of NRW on physiological activation in three BSC successional stages, including the cyanobacteria crust stage (Crust-C), moss colonization stage (Crust-CM), and moss crust stage (Crust-M), were studied in situ. Results suggest NRW inputs hydrated and activated physiological activity (Fv/Fm, carbon exchange, and nitrogen fixation) in BSCs but led to a negative carbon balance and low rates of nitrogen fixation in BSCs. One effective NRW event could hydrate BSCs for 7 h. Following simulated rainfall, the physiological activities recovered within 3 h, and net carbon gain occurred until 3 h after hydration, whereas NRW-induced physiological recovery processes were slower and exhibited lower activities, leading to a negative carbon balance. There were significant positive correlations between NRW amounts and the recovered values of Fv/Fm in all the three BSC stages (p < .001). The thresholds for Fv/Fm activation decreased with BSC succession, and the annual effective NRW events increased with BSC succession, with values of 29.8, 89.2, and 110.7 in Crust-C, Crust-CM and Crust-M, respectively. The results suggest that moss crust and moss-cyanobacteria crust use NRW to prolong metabolic activity and reduce drought stress more efficiently than cyanobacteria crusts. Therefore, these results suggest that BSCs utilize NRW to sustain life while growth and biomass accumulation require precipitation (rainfall) events over a certain threshold.

AP-1 proteins in the adult brain: facts and fiction about effectors of neuroprotection and neurodegeneration.

PubMed

Herdegen, T; Waetzig, V

2001-04-30

Jun and Fos proteins are induced and activated following most physiological and pathophysiological stimuli in the brain. Only few data allow conclusions about distinct functions of AP-1 proteins in neurodegeneration and neuroregeneration, and these functions mainly refer to c-Jun and its activation by JNKs. Apoptotic functions of activated c-Jun affect hippocampal, nigral and primary cultured neurons following excitotoxic stimulation and destruction of the neuron-target-axis including withdrawal of trophic molecules. The inhibition of JNKs might exert neuroprotection by subsequent omission of c-Jun activation. Besides endogenous neuronal functions, the c-Jun/AP-1 proteins can damage the nervous system by upregulation of harmful programs in non-neuronal cells (e.g. microglia) with release of neurodegenerative molecules. In contrast, the differentiation with neurite extension and maturation of neural cells in vitro indicate physiological and potentially neuroprotective functions of c-Jun and JNKs including sensoring for alterations in the cytoskeleton. This review summarizes the multiple molecular interfunctions which are involved in the shift from the physiological role to degenerative effects of the Jun/JNK-axis such as cell type-specific expression and intracellular localization of scaffold proteins and upstream activators, antagonistic phosphatases, interaction with other kinase systems, or the activation of transcription factors competing for binding to JNK proteins and AP-1 DNA elements.

Physiology of Sedentary Behavior and Its Relationship to Health Outcomes

PubMed Central

Thyfault, John P; Du, Mengmeng; Kraus, William E; Levine, James A; Booth, Frank W

2014-01-01

Purpose This paper reports on the findings and recommendations of the “Physiology of Sedentary Behavior and its Relationship to Health Outcomes” group, a part of a larger workshop entitled Sedentary Behavior: Identifying Research Priorities sponsored by the National Heart, and Lung and Blood Institute and the National Institute on Aging, which aimed to establish sedentary behavior research priorities. Methods The discussion within our workshop lead to the formation of critical physiological research objectives related to sedentary behaviors, that if appropriately researched would greatly impact our overall understanding of human health and longevity. Results and Conclusions Primary questions are related to physiological “health outcomes” including the influence of physical activity vs. sedentary behavior on function of a number of critical physiological systems (aerobic capacity, skeletal muscle metabolism and function, telomeres/genetic stability, and cognitive function). The group also derived important recommendations related to the “central and peripheral mechanisms” that govern sedentary behavior and how energy balance has a role in mediating these processes. General recommendations for future sedentary physiology research efforts include that studies of sedentary behavior, including that of sitting time only, should focus on the physiological impact of a “lack of human movement” in contradistinction to the effects of physical movement and that new models or strategies for studying sedentary behavior induced adaptations and links to disease development are needed to elucidate underlying mechanism(s). PMID:25222820

EVA Physiology and Medical Considerations Working in the Suit

NASA Technical Reports Server (NTRS)

Parazynski, Scott

2012-01-01

This "EVA Physiology and Medical Considerations Working in the Suit" presentation covers several topics related to the medical implications and physiological effects of suited operations in space from the perspective of a physician with considerable first-hand Extravehicular Activity (EVA) experience. Key themes include EVA physiology working in a pressure suit in the vacuum of space, basic EVA life support and work support, Thermal Protection System (TPS) inspections and repairs, and discussions of the physical challenges of an EVA. Parazynski covers the common injuries and significant risks during EVAs, as well as physical training required to prepare for EVAs. He also shares overall suit physiological and medical knowledge with the next generation of Extravehicular Mobility Unit (EMU) system designers.

Social Support and Heart Failure: Differing Effects by Race

DTIC Science & Technology

2015-05-11

responses. These compensatory physiologic responses include increased sympathetic nervous system activity, inflammation, and constriction of blood vessels... physiological differences between African Americans and Caucasians. For instance the process by which sodium is processed in the body may vary between...associated cardiovascular and inflammatory diseases (76). One important hormone at work in the cardiovascular system is aldosterone and it may have a

APS: 125 Years of Progress of Physiology as a Scientific Discipline and a Profession

ERIC Educational Resources Information Center

Carroll, Robert G.; Frank, Martin; Ra'anan, Alice; Matyas, Marsha L.

2013-01-01

The Experimental Biology 2012 meeting in San Diego, CA, included events to celebrate the 125th anniversary of the founding of the American Physiological Society (APS) and reflect on the recent accomplishments of the society. Most of the APS activities in the past quarter century were guided by a series of strategic plans. Membership in the APS…

Physiological indices of seawater readiness in postspawning steelhead kelts

USGS Publications Warehouse

Buelow, Jessica; Moffitt, Christine M.

2015-01-01

Management goals to improve the recovery of steelhead (Oncorhynchus mykiss) stocks at risk of extinction include increasing the proportion of postspawning fish that survive and spawn again. To be successful, postspawning steelhead (kelts) migrating downstream to the ocean must prepare physiologically and physically for a seawater transition. We sampled blood, gill filaments, and evaluated the external condition of migrating kelts from an ESA-listed population in the Snake/Columbia River system over two consecutive years to evaluate their physiological readiness for transition to seawater. We chose attributes often considered as measures of preparation for seawater in juveniles, including gill Na+,K+ ATPase activity, plasma electrolytes and hormones to consider factors related to external condition, size and sex. We found kelts in good external condition had plasma profiles similar to downstream-migrating smolts. In addition, we found more than 80% of kelts ranked in good external condition had smolt-like body silvering. We compared measures from migrating kelts with samples obtained from hatchery fish at the time of spawning to confirm that Na+, K+ ATPase activity in kelts was significantly elevated over spawning fish. We found significant differences in gill Na+, K+ ATPase activity in migrating kelts between the years of sampling, but little indication of influence of fish condition. We conclude that the postspawning steelhead sampled exhibited a suite of behaviours, condition and physiology characteristic of fish prepared for successful transition to a seawater environment.

The Evolution of the Physical Activity Field

ERIC Educational Resources Information Center

Blair, Steven N.; Powell, Kenneth E.

2014-01-01

This article includes an historical review of research on physical activity and health, and how the findings have contributed to physical activity participation and promotion today. In the 20th century, research began to accumulate on the effects of exercise on physiological functions, and later on the relation between regular activity and various…

Health Occupations Education: Medical Assistant.

ERIC Educational Resources Information Center

Sloan, Jamee Reid

These medical assistant instructional materials include 28 instructional units organized into sections covering orientation; anatomy and physiology, related disorders, disease, and skills; office practices; and clinical practices. Each unit includes eight basic components: performance objectives, suggested activities for teachers, information…

Hippocampal mechanisms for the context-dependent retrieval of episodes

PubMed Central

Hasselmo, Michael E.; Eichenbaum, Howard B.

2008-01-01

Behaviors ranging from delivering newspapers to waiting tables depend on remembering previous episodes to avoid incorrect repetition. Physiologically, this requires mechanisms for long-term storage and selective retrieval of episodes based on time of occurrence, despite variable intervals and similarity of events in a familiar environment. Here, this process has been modeled based on physiological properties of the hippocampal formation, including mechanisms for sustained activity in entorhinal cortex and theta rhythm oscillations in hippocampal subregions. The model simulates the context-sensitive firing properties of hippocampal neurons including trial specific firing during spatial alternation and trial by trial changes in theta phase precession on a linear track. This activity is used to guide behavior, and lesions of the hippocampal network impair memory-guided behavior. The model links data at the cellular level to behavior at the systems level, describing a physiologically plausible mechanism for the brain to recall a given episode which occurred at a specific place and time. PMID:16263240

Free fatty acid receptors and their role in regulation of energy metabolism.

PubMed

Hara, Takafumi; Kimura, Ikuo; Inoue, Daisuke; Ichimura, Atsuhiko; Hirasawa, Akira

2013-01-01

The free fatty acid receptor (FFAR) is a G protein-coupled receptor (GPCR) activated by free fatty acids (FFAs), which play important roles not only as essential nutritional components but also as signaling molecules in numerous physiological processes. In the last decade, FFARs have been identified by the GPCR deorphanization strategy derived from the human genome database. To date, several FFARs have been identified and characterized as critical components in various physiological processes. FFARs are categorized according to the chain length of FFA ligands that activate each FFAR; FFA2 and FFA3 are activated by short chain FFAs, GPR84 is activated by medium-chain FFAs, whereas FFA1 and GPR120 are activated by medium- or long-chain FFAs. FFARs appear to act as physiological sensors for food-derived FFAs and digestion products in the gastrointestinal tract. Moreover, they are considered to be involved in the regulation of energy metabolism mediated by the secretion of insulin and incretin hormones and by the regulation of the sympathetic nerve systems, taste preferences, and inflammatory responses related to insulin resistance. Therefore, because FFARs can be considered to play important roles in physiological processes and various pathophysiological processes, FFARs have been targeted in therapeutic strategies for the treatment of metabolic disorders including type 2 diabetes and metabolic syndrome. In this review, we present a summary of recent progress regarding the understanding of their physiological roles in the regulation of energy metabolism and their potential as therapeutic targets.

Regulation of Bim in Health and Disease

PubMed Central

Sionov, Ronit Vogt; Vlahopoulos, Spiros A.; Granot, Zvi

2015-01-01

The BH3-only Bim protein is a major determinant for initiating the intrinsic apoptotic pathway under both physiological and pathophysiological conditions. Tight regulation of its expression and activity at the transcriptional, translational and post-translational levels together with the induction of alternatively spliced isoforms with different pro-apoptotic potential, ensure timely activation of Bim. Under physiological conditions, Bim is essential for shaping immune responses where its absence promotes autoimmunity, while too early Bim induction eliminates cytotoxic T cells prematurely, resulting in chronic inflammation and tumor progression. Enhanced Bim induction in neurons causes neurodegenerative disorders including Alzheimer's, Parkinson's and Huntington's diseases. Moreover, type I diabetes is promoted by genetically predisposed elevation of Bim in β-cells. On the contrary, cancer cells have developed mechanisms that suppress Bim expression necessary for tumor progression and metastasis. This review focuses on the intricate network regulating Bim activity and its involvement in physiological and pathophysiological processes. PMID:26405162

Bioresorbable silicon electronics for transient spatiotemporal mapping of electrical activity from the cerebral cortex.

PubMed

Yu, Ki Jun; Kuzum, Duygu; Hwang, Suk-Won; Kim, Bong Hoon; Juul, Halvor; Kim, Nam Heon; Won, Sang Min; Chiang, Ken; Trumpis, Michael; Richardson, Andrew G; Cheng, Huanyu; Fang, Hui; Thomson, Marissa; Bink, Hank; Talos, Delia; Seo, Kyung Jin; Lee, Hee Nam; Kang, Seung-Kyun; Kim, Jae-Hwan; Lee, Jung Yup; Huang, Younggang; Jensen, Frances E; Dichter, Marc A; Lucas, Timothy H; Viventi, Jonathan; Litt, Brian; Rogers, John A

2016-07-01

Bioresorbable silicon electronics technology offers unprecedented opportunities to deploy advanced implantable monitoring systems that eliminate risks, cost and discomfort associated with surgical extraction. Applications include postoperative monitoring and transient physiologic recording after percutaneous or minimally invasive placement of vascular, cardiac, orthopaedic, neural or other devices. We present an embodiment of these materials in both passive and actively addressed arrays of bioresorbable silicon electrodes with multiplexing capabilities, which record in vivo electrophysiological signals from the cortical surface and the subgaleal space. The devices detect normal physiologic and epileptiform activity, both in acute and chronic recordings. Comparative studies show sensor performance comparable to standard clinical systems and reduced tissue reactivity relative to conventional clinical electrocorticography (ECoG) electrodes. This technology offers general applicability in neural interfaces, with additional potential utility in treatment of disorders where transient monitoring and modulation of physiologic function, implant integrity and tissue recovery or regeneration are required.

Regulation of Bim in Health and Disease.

PubMed

Sionov, Ronit Vogt; Vlahopoulos, Spiros A; Granot, Zvi

2015-09-15

The BH3-only Bim protein is a major determinant for initiating the intrinsic apoptotic pathway under both physiological and pathophysiological conditions. Tight regulation of its expression and activity at the transcriptional, translational and post-translational levels together with the induction of alternatively spliced isoforms with different pro-apoptotic potential, ensure timely activation of Bim. Under physiological conditions, Bim is essential for shaping immune responses where its absence promotes autoimmunity, while too early Bim induction eliminates cytotoxic T cells prematurely, resulting in chronic inflammation and tumor progression. Enhanced Bim induction in neurons causes neurodegenerative disorders including Alzheimer's, Parkinson's and Huntington's diseases. Moreover, type I diabetes is promoted by genetically predisposed elevation of Bim in β-cells. On the contrary, cancer cells have developed mechanisms that suppress Bim expression necessary for tumor progression and metastasis. This review focuses on the intricate network regulating Bim activity and its involvement in physiological and pathophysiological processes.

Endothelium and Its Alterations in Cardiovascular Diseases: Life Style Intervention

PubMed Central

Paganelli, Corrado; Buffoli, Barbara; Rodella, Luigi Fabrizio; Rezzani, Rita

2014-01-01

The endothelium, which forms the inner cellular lining of blood vessels and lymphatics, is a highly metabolically active organ that is involved in many physiopathological processes, including the control of vasomotor tone, barrier function, leukocyte adhesion, and trafficking and inflammation. In this review, we summarized and described the following: (i) endothelial cell function in physiological conditions and (ii) endothelial cell activation and dysfunction in the main cardiovascular diseases (such as atherosclerosis, and hypertension) and to diabetes, cigarette smoking, and aging physiological process. Finally, we presented the currently available evidence that supports the beneficial effects of physical activity and various dietary compounds on endothelial functions. PMID:24719887

Roles of Nicotinamide Adenine Dinucleotide Phosphate (NADPH) Oxidase in Angiogenesis: Isoform-Specific Effects

PubMed Central

Wang, Haibo; Hartnett, M. Elizabeth

2017-01-01

Angiogenesis is the formation of new blood vessels from preexisting ones and is implicated in physiologic vascular development, pathologic blood vessel growth, and vascular restoration. This is in contrast to vasculogenesis, which is de novo growth of vessels from vascular precursors, or from vascular repair that occurs when circulating endothelial progenitor cells home into an area and develop into blood vessels. The objective of this review is to discuss the isoform-specific role of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) in physiologic and pathologic angiogenesis and vascular repair, but will not specifically address vasculogenesis. As the major source of reactive oxygen species (ROS) in vascular endothelial cells (ECs), NOX has gained increasing attention in angiogenesis. Activation of NOX leads to events necessary for physiologic and pathologic angiogenesis, including EC migration, proliferation and tube formation. However, activation of different NOX isoforms has different effects in angiogenesis. Activation of NOX2 promotes pathologic angiogenesis and vascular inflammation, but may be beneficial in revascularization in the hindlimb ischemic model. In contrast, activation of NOX4 appears to promote physiologic angiogenesis mainly by protecting the vasculature during ischemia, hypoxia and inflammation and by restoring vascularization, except in models of oxygen-induced retinopathy and diabetes where NOX4 activation leads to pathologic angiogenesis. PMID:28587189

The conservation physiology toolbox: status and opportunities

PubMed Central

Love, Oliver P; Hultine, Kevin R

2018-01-01

Abstract For over a century, physiological tools and techniques have been allowing researchers to characterize how organisms respond to changes in their natural environment and how they interact with human activities or infrastructure. Over time, many of these techniques have become part of the conservation physiology toolbox, which is used to monitor, predict, conserve, and restore plant and animal populations under threat. Here, we provide a summary of the tools that currently comprise the conservation physiology toolbox. By assessing patterns in articles that have been published in ‘Conservation Physiology’ over the past 5 years that focus on introducing, refining and validating tools, we provide an overview of where researchers are placing emphasis in terms of taxa and physiological sub-disciplines. Although there is certainly diversity across the toolbox, metrics of stress physiology (particularly glucocorticoids) and studies focusing on mammals have garnered the greatest attention, with both comprising the majority of publications (>45%). We also summarize the types of validations that are actively being completed, including those related to logistics (sample collection, storage and processing), interpretation of variation in physiological traits and relevance for conservation science. Finally, we provide recommendations for future tool refinement, with suggestions for: (i) improving our understanding of the applicability of glucocorticoid physiology; (ii) linking multiple physiological and non-physiological tools; (iii) establishing a framework for plant conservation physiology; (iv) assessing links between environmental disturbance, physiology and fitness; (v) appreciating opportunities for validations in under-represented taxa; and (vi) emphasizing tool validation as a core component of research programmes. Overall, we are confident that conservation physiology will continue to increase its applicability to more taxa, develop more non-invasive techniques, delineate where limitations exist, and identify the contexts necessary for interpretation in captivity and the wild. PMID:29942517

ACTIVATION ASSAY FOR PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR- ALPHA (PPARÁ) BY PERFLUOROALKYL ACIDS (PFAAS) IN COS-1 CELLS

EPA Science Inventory

PFAAs have been found to elicit various physiological effects including peroxisome proliferation, indicating the mechanism of action for these chemicals could involve PPAR. This study investigates the ability of PFAAs to bind and activate mouse and human PPARα in COS-1 cell...

Syndecan-4 Signaling Is Required for Exercise-Induced Cardiac Hypertrophy

PubMed Central

Xie, Jun; He, Guixin; Chen, Qinhua; Sun, Jiayin; Dai, Qin; Lu, Jianrong; Li, Guannan; Wu, Han; Li, Ran; Chen, Jianzhou; Xu, Wei; Xu, Biao

2016-01-01

Cardiac hypertrophy can be broadly classified as either physiological or pathological. Physiological stimuli such as exercise cause adaptive cardiac hypertrophy and normal heart function. Pathological stimuli including hypertension and aortic valvular stenosis cause maladaptive cardiac remodeling and ultimately heart failure. Syndecan-4 (synd4) is a transmembrane proteoglycan identified as being involved in cardiac adaptation after injury, but whether it takes part in physiological cardiac hypertrophy is unclear. We observed upregulation of synd4 in exercise-induced hypertrophic myocardium. To evaluate the role of synd4 in the physiological form of cardiac hypertrophy, mice lacking synd4 (synd4–/–) were exercised by swimming for 4 wks. Ultrasonic cardiogram (UCG) and histological analysis revealed that swimming induced the hypertrophic phenotype but was blunted in synd4–/– compared with wild-type (WT) mice. The swimming-induced activation of Akt, a key molecule in physiological hypertrophy was also more decreased than in WT controls. In cultured cardiomyocytes, synd4 overexpression could induce cell enlargement, protein synthesis and distinct physiological molecular alternation. Akt activation also was observed in synd4-overexpressed cardiomyocytes. Furthermore, inhibition of protein kinase C (PKC) prevented the synd4-induced hypertrophic phenotype and Akt phosphorylation. This study identified an essential role of synd4 in mediation of physiological cardiac hypertrophy. PMID:26835698

Physiology of Hyperuricemia and Urate-Lowering Treatments.

PubMed

Benn, Caroline L; Dua, Pinky; Gurrell, Rachel; Loudon, Peter; Pike, Andrew; Storer, R Ian; Vangjeli, Ciara

2018-01-01

Gout is the most common form of inflammatory arthritis and is a multifactorial disease typically characterized by hyperuricemia and monosodium urate crystal deposition predominantly in, but not limited to, the joints and the urinary tract. The prevalence of gout and hyperuricemia has increased in developed countries over the past two decades and research into the area has become progressively more active. We review the current field of knowledge with emphasis on active areas of hyperuricemia research including the underlying physiology, genetics and epidemiology, with a focus on studies which suggest association of hyperuricemia with common comorbidities including cardiovascular disease, renal insufficiency, metabolic syndrome and diabetes. Finally, we discuss current therapies and emerging drug discovery efforts aimed at delivering an optimized clinical treatment strategy.

An investigation into the relationship between age and physiological function in highly active older adults

PubMed Central

Pollock, Ross D; Carter, Scott; Velloso, Cristiana P; Duggal, Niharika A; Lord, Janet M; Lazarus, Norman R; Harridge, Stephen D R

2015-01-01

Despite extensive research, the relationship between age and physiological function remains poorly characterised and there are currently no reliable markers of human ageing. This is probably due to a number of confounding factors, particularly in studies of a cross-sectional nature. These include inter-subject genetic variation, as well as inter-generational differences in nutrition, healthcare and insufficient levels of physical activity as well as other environmental factors. We have studied a cohort of highly and homogeneously active older male (n = 84) and female (n = 41) cyclists aged 55–79 years who it is proposed represent a model for the study of human ageing free from the majority of confounding factors, especially inactivity. The aim of the study was to identify physiological markers of ageing by assessing the relationship between function and age across a wide range of indices. Each participant underwent a detailed physiological profiling which included measures of cardiovascular, respiratory, neuromuscular, metabolic, endocrine and cognitive functions, bone strength, and health and well-being. Significant associations between age and function were observed for many functions. The maximal rate of oxygen consumption ( showed the closest association with age (r = −0.443 to −0.664; P < 0.001), but even here the variance in age for any given level was high, precluding the clear identification of the age of any individual. The results of this cross-sectional study suggest that even when many confounding variables are removed the relationship between function and healthy ageing is complex and likely to be highly individualistic and that physical activity levels must be taken into account in ageing studies. Key Points The relationship between age and physiological function remains poorly defined and there are no physiological markers that can be used to reliably predict the age of an individual. This could be due to a variety of confounding genetic and lifestyle factors, and in particular to ill-defined and low levels of physical activity. This study assessed the relationship between age and a diverse range of physiological functions in a cohort of highly active older individuals (cyclists) aged 55–79 years in whom the effects of lifestyle factors would be ameliorated. Significant associations between age and function were observed for many functions. was most closely associated with age, but even here the variance in age for any given level was high, precluding the clear identification of the age of any individual. The data suggest that the relationship between human ageing and physiological function is highly individualistic and modified by inactivity. PMID:25565071

Defining the Physiological Factors that Contribute to Postflight Changes in Functional Performance

NASA Technical Reports Server (NTRS)

Bloomberg, J. J.; Arzeno, N.; Buxton, R.; Feiveson, A. H.; Kofman, I.; Lawrence, E.; Lee, S. M. C.; Mulavara, A. P.; Peters, B. T.; Platts, S. H.;

Community-level physiological profiles of microorganisms inhabiting soil contaminated with heavy metals

NASA Astrophysics Data System (ADS)

Kuźniar, Agnieszka; Banach, Artur; Stępniewska, Zofia; Frąc, Magdalena; Oszust, Karolina; Gryta, Agata; Kłos, Marta; Wolińska, Agnieszka

2018-01-01

The aim of the study was to assess the differences in the bacterial community physiological profiles in soils contaminated with heavy metals versus soils without metal contaminations. The study's contaminated soil originated from the surrounding area of the Szopienice non-ferrous metal smelter (Silesia Region, Poland). The control was soil unexposed to heavy metals. Metal concentration was appraised by flame atomic absorption spectrometry, whereas the the community-level physiological profile was determined with the Biolog EcoPlatesTM system. The soil microbiological activity in both sites was also assessed via dehydrogenase activity. The mean concentrations of metals (Cd and Zn) in contaminated soil samples were in a range from 147.27 to 12265.42 mg kg-1, and the heavy metal contamination brought about a situation where dehydrogenase activity inhibition was observed mostly in the soil surface layers. Our results demonstrated that there is diversity in the physiological profiles of microorganisms inhabiting contaminated and colntrol soils; therefore, for assessment purposes, these were treated as two clusters. Cluster I included colntrol soil samples in which microbial communities utilised most of the available substrates. Cluster II incorporated contaminated soil samples in which a smaller number of the tested substrates was utilised by the contained microorganisms. The physiological profiles of micro-organisms inhabiting the contaminated and the colntrol soils are distinctly different.

Role of central vagal 5-HT3 receptors in gastrointestinal physiology and pathophysiology

PubMed Central

Browning, Kirsteen N.

2015-01-01

Vagal neurocircuits are vitally important in the co-ordination and modulation of GI reflexes and homeostatic functions. 5-hydroxytryptamine (5-HT; serotonin) is critically important in the regulation of several of these autonomic gastrointestinal (GI) functions including motility, secretion and visceral sensitivity. While several 5-HT receptors are involved in these physiological responses, the ligand-gated 5-HT3 receptor appears intimately involved in gut-brain signaling, particularly via the afferent (sensory) vagus nerve. 5-HT is released from enterochromaffin cells in response to mechanical or chemical stimulation of the GI tract which leads to activation of 5-HT3 receptors on the terminals of vagal afferents. 5-HT3 receptors are also present on the soma of vagal afferent neurons, including GI vagal afferent neurons, where they can be activated by circulating 5-HT. The central terminals of vagal afferents also exhibit 5-HT3 receptors that function to increase glutamatergic synaptic transmission to second order neurons of the nucleus tractus solitarius within the brainstem. While activation of central brainstem 5-HT3 receptors modulates visceral functions, it is still unclear whether central vagal neurons, i.e., nucleus of the tractus solitarius (NTS) and dorsal motor nucleus of the vagus (DMV) neurons themselves also display functional 5-HT3 receptors. Thus, activation of 5-HT3 receptors may modulate the excitability and activity of gastrointestinal vagal afferents at multiple sites and may be involved in several physiological and pathophysiological conditions, including distention- and chemical-evoked vagal reflexes, nausea, and vomiting, as well as visceral hypersensitivity. PMID:26578870

Estimation of physiological sub-millimeter displacement with CW Doppler radar.

PubMed

Jia Xu; Xiaomeng Gao; Padasdao, Bryson E; Boric-Lubecke, Olga

2015-01-01

Doppler radar physiological sensing has been studied for non-contact detection of vital signs including respiratory and heartbeat rates. This paper presents the first micrometer resolution Wi-Fi band Doppler radar for sub-millimeter physiological displacement measurement. A continuous-wave Doppler radar working at 2.4GHz is used for the measurement. It is intended for estimating small displacements on the body surface resulting from physiological activity. A mechanical mover was used as target, and programmed to conduct sinusoidal motions to simulate pulse motions. Measured displacements were compared with a reference system, which indicates a superior performance in accuracy for having absolute errors less than 10μm, and relative errors below 4%. It indicates the feasibility of highly accurate non-contact monitoring of physiological movements using Doppler radar.

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.

Color-Coded Organelles.

ERIC Educational Resources Information Center

McLaughlin, Esther; And Others

1994-01-01

Describes how red beets can be used to demonstrate a variety of membrane phenomena. Some of the activities include observation of vacuoles; vacuoles in intact cells; isolation of vacuoles in physiological studies; demonstration of membrane integrity; and demonstration of ion diffusion and active transport with purified vacuoles. (ZWH)

Instructional Improvement Listening Handbook. Secondary Level.

ERIC Educational Resources Information Center

Crapse, Larry

Stressing that the importance of listening carefully cannot be underestimated, this handbook describes the process of listening (including the five components--previous knowledge, listening material, physiological activity, attention, and intellectual activity), some barriers to efficient listening, and bad and good listening habits. It also…

Platelet Activation by Streptococcus pyogenes Leads to Entrapment in Platelet Aggregates, from Which Bacteria Subsequently Escape

PubMed Central

Svensson, Lisbeth; Baumgarten, Maria; Mörgelin, Matthias

2014-01-01

Platelet activation and aggregation have been reported to occur in response to a number of Gram-positive pathogens. Here, we show that platelet aggregates induced by Streptococcus pyogenes were unstable and that viable bacteria escaped from the aggregates over time. This was not due to differential activation in response to the bacteria compared with physiological activators. All the bacterial isolates induced significant platelet activation, including integrin activation and alpha and dense-granule release, at levels equivalent to those induced by potent physiological platelet activators that induced stable aggregates. The ability to escape the aggregates and to resist the antibacterial effects of platelets was dependent on active protein synthesis by the bacteria within the aggregate. We conclude that S. pyogenes bacteria can temporarily cover themselves with activated platelets, and we propose that this may facilitate survival of the bacteria in the presence of platelets. PMID:25069984

Competitive active video games: Physiological and psychological responses in children and adolescents.

PubMed

Lisón, Juan F; Cebolla, Ausias; Guixeres, Jaime; Álvarez-Pitti, Julio; Escobar, Patricia; Bruñó, Alejandro; Lurbe, Empar; Alcañiz, Mariano; Baños, Rosa

2015-10-01

Recent strategies to reduce sedentary behaviour in children include replacing sedentary screen time for active video games. Active video game studies have focused principally on the metabolic consumption of a single player, with physiological and psychological responses of opponent-based multiplayer games to be further evaluated. To determine whether adding a competitive component to playing active video games impacts physiological and psychological responses in players. Sixty-two healthy Caucasian children and adolescents, nine to 14 years years of age, completed three conditions (8 min each) in random order: treadmill walking, and single and opponent-based Kinect active video games. Affect, arousal, rate of perceived exertion, heart rate and percentage of heart rate reserve were measured for each participant and condition. Kinect conditions revealed significantly higher heart rate, percentage of heart rate reserve, rate of perceived exertion and arousal when compared with treadmill walking (P<0.001). Opponent-based condition revealed lower values for the rate of perceived exertion (P=0.02) and higher affect (P=0.022) when compared with single play. Competitive active video games improved children's psychological responses (affect and rate of perceived exertion) compared with single play, providing a solution that may contribute toward improved adherence to physical activity.

Psychological and physiological responses during an exam and their relation to personality characteristics.

PubMed

Spangler, G

1997-08-01

The aim of the study was to compare emotional and physiological responses to real and control examinations and to assess their relation to personality characteristics. Emotional responses were assessed by state anxiety and perceived stress. The assessment of physiological responses included the activity of the cardiac system (heart periods, vagal tone), the adrenocortical system (cortisol) and the immune system (immune globulin A, sIgA). Emotional and physiological responses of 23 students (12 males, 11 females) were assessed during an oral exam at the end of a basic course in psychology which was a prerequisite for the students' final exams. For the control condition physiological responses were assessed one week before the examination during a memory test. The findings of the study demonstrate different emotional and physiological response patterns to examinations as compared to the control condition. Heightened anxiety was observed only before the exam. Whereas within-situation physiological responses (higher heart periods, cortisol, and sIgA; lower vagal tone) were observed both under the exam and control condition, responses to exam condition indicated pre-exam anticipatory activation and post-exam restricted recovery responses. With regard to personality characteristics subjects with high ego-resiliency showed more flexible adaptation than subjects with low ego-resiliency both on the emotional level (anxiety down-regulation after exam) and on the physiological level (situation-specific responses, quick recovery). Subjects with high ego-control exhibited a lower physiological reactivity under both conditions, i.e. they seemed to maintain longer their control also on a physiological level independent of the type of situation.

Relationship of psychological and physiological parameters during an arctic ski expedition

NASA Astrophysics Data System (ADS)

Bishop, Sheryl L.; Grobler, Lukas C.; SchjØll, Olaf

2001-08-01

Considerable data (primarily physiological) have been collected during expeditions in extreme environments over the last century. Physiological measurements have only recently been examined in association with the emotional or behavioral state of the subject. Establishing this psychophysiological relationship is essential to understanding fully the adaptation of humans to the stresses of extreme environments. This pilot study investigated the simultaneous collection of physiological, psychological and behavioral data from a two-man Greenland expedition in order to model how specific relationships between physiological and psychological adaptation to a polar environment may be identified. The data collected describes changes in adrenal and other hormonal activity and psychological functioning. Levels of cortisol and testosterone were calculated. Factors influencing the plasma profiles of the aforementioned included 24-hour sunlight, high calorific intake of more than 28 000 kJ/day and extreme physical exercise. There was a difference between individual psychological profiles as well as self-report stress and physiological stress.

Physiological relaxation induced by horticultural activity: transplanting work using flowering plants.

PubMed

Lee, Min-sun; Park, Bum-jin; Lee, Juyoung; Park, Kun-tae; Ku, Ja-hyeong; Lee, Jun-woo; Oh, Kyung-ok; Miyazaki, Yoshifumi

2013-10-10

Despite increasing attention and a growing volume of research data, little physiological evidence is available on the benefits of horticultural activity and the different effects on individuals. Therefore, the aim of the present study was to investigate the physiological effects of horticultural activity and to examine how differences in personality alter these effects. The effects of transplanting real flowers (horticultural activity) and handling artificial flowers (control activity) on human physiological activity were compared. On the first day, eight participants engaged in horticultural activity and another eight in the control activity. On the second day, participants switched roles. Participants' physiological conditions during each activity were assessed by measuring the heart rate and heart rate variability (HRV). Psychological responses, which were measured using a semantic differential rating scale, showed that the horticultural activity promoted comfortable, soothed, and natural feelings, compared to the control activity. Analysis of physiological responses using two-way repeated measures analysis of variance (ANOVA) revealed that sympathetic nervous activity significantly decreased in the late time period (11 to 15 minutes) of horticultural activity only in the type A group. This study supports the fact that the horticultural activity can enhance psychological and physiological relaxation effects, although these physiological effects can differ among individuals with different personalities.

Physiological relaxation induced by horticultural activity: transplanting work using flowering plants

PubMed Central

2013-01-01

Background Despite increasing attention and a growing volume of research data, little physiological evidence is available on the benefits of horticultural activity and the different effects on individuals. Therefore, the aim of the present study was to investigate the physiological effects of horticultural activity and to examine how differences in personality alter these effects. Results The effects of transplanting real flowers (horticultural activity) and handling artificial flowers (control activity) on human physiological activity were compared. On the first day, eight participants engaged in horticultural activity and another eight in the control activity. On the second day, participants switched roles. Participants’ physiological conditions during each activity were assessed by measuring the heart rate and heart rate variability (HRV). Psychological responses, which were measured using a semantic differential rating scale, showed that the horticultural activity promoted comfortable, soothed, and natural feelings, compared to the control activity. Analysis of physiological responses using two-way repeated measures analysis of variance (ANOVA) revealed that sympathetic nervous activity significantly decreased in the late time period (11 to 15 minutes) of horticultural activity only in the type A group. Conclusions This study supports the fact that the horticultural activity can enhance psychological and physiological relaxation effects, although these physiological effects can differ among individuals with different personalities. PMID:24112302

Nuclear Receptor Coactivator Function in Reproductive Physiology and Behavior

PubMed Central

Molenda, Heather A.; Kilts, Caitlin P.; Allen, Rachel L.; Tetel, Marc J.

2009-01-01

Gonadal steroid hormones act throughout the body to elicit changes in gene expression that result in profound effects on reproductive physiology and behavior. Steroid hormones exert many of these effects by binding to their respective intracellular receptors, which are members of a nuclear receptor superfamily of transcriptional activators. A variety of in vitro studies indicate that nuclear receptor coactivators are required for efficient transcriptional activity of steroid receptors. Many of these coactivators are found in a variety of steroid hormone-responsive reproductive tissues, including the reproductive tract, mammary gland, and brain. While many nuclear receptor coactivators have been investigated in vitro, we are only now beginning to understand their function in reproductive physiology and behavior. In this review, we discuss the general mechanisms of action of nuclear receptor coactivators in steroid-dependent gene transcription. We then review some recent and exciting findings on the function of nuclear receptor coactivators in steroid-dependent brain development and reproductive physiology and behavior. PMID:12855594

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 departments were changing their titles to reflect a stronger science orientation, many established laboratories and offered degree programs devoted to Applied Physiology. We concluded that Applied Physiology has been an important contributor to the discipline of physiology while becoming an integral component of APS. Copyright © 2016 the American Physiological Society.

Skylab hardware report operational bioinstrumentation system

NASA Technical Reports Server (NTRS)

Luczkowski, S.

1977-01-01

The Skylab Operational Bioinstrumentation System is a personal, individually adjustable biomedical system designed to monitor the basic physiological functions of each suited crewman during specified periods of a manned space mission. The basic physiological functions of this system include electrocardiogram, respiration by impedance pneumogram, body temperature, cardiotachometer, and subject identification. The Operational Bioinstrumentation System was scheduled to monitor each crewman during launch, extravehicular activities, suited intravehicular experiments, and undocking and return.

Research in Biological and Medical Sciences Including Biochemistry, Communicable Disease and Immunology, Internal Medicine, Physiology, Psychiatry, Surgery, and Veterinary Medicine. Volume 1

DTIC Science & Technology

1979-09-01

and R.P. MacDermott. Antibody-dependent cell-mediated antibacterial activity of human mononuclear cells. I. K-lymphocytes and monocytes are effective...malaria research. During the reporting period, research activities have included analyses of: 1) a hemagglutination inhibition test for early detection of...radioiodination or sodium borohydride reduction. Evaluate the potential roles of activity for each protein isolated. Compare the composition of isolated

Sport for All. Exercise and Health.

ERIC Educational Resources Information Center

Astrand, Per-Olof

This booklet is divided into seven sections that include the following topics: (a) physical performance, (b) adaptation to inactivity and activity, (c) physiological and medical motives for regular physical activity, (d) training, (e) physical fitness for everyday life, and (f) testing physical fitness and condition. Section one discusses energy…

Physiologic and behavioral effects of papoose board on anxiety in dental patients with special needs.

PubMed

Chen, Hsin-Yung; Yang, Hsiang; Chi, Huang-Ju; Chen, Hsin-Ming

2014-02-01

Anxiety induced by dental treatment can become a serious problem, especially for patients with special needs. Application of deep touch pressure, which is a sensory adaptation technique, may ameliorate anxiety in disabled patients. However, few empiric studies have investigated the possible links between the clinical effects of deep touch pressure and its behavioral and physiologic aspects. Equally little progress has been made concerning theoretical development. The current study is a crossover intervention trial to investigate the behavioral and physiological effects of deep touch pressure for participants receiving dental treatment. Nineteen disabled participants, who were retrospectively subclassified for positive trend or negative trend, were recruited to receive the papoose board as an application of deep touch pressure. Quantitative analyses of behavioral assessments and physiological measurements, including electrodermal activity and heart rate variability, were conducted. We sought to understand the modulation of the autonomic nervous system and the orchestration of sympathetic and parasympathetic (PsNS) nervous systems. Behavioral assessments reported that higher levels of anxiety were induced by the dental treatment for participants with both groups of positive and negative trends. Although no significant differences were found in the SNS activity, physiologic responses indicated that significantly changes of PsNS activity were observed under the stress condition (dental treatment) when deep touch pressure intervention was applied, especially for participants in the group of positive trend. Our results suggest that the PsNS activation plays a critical role in the process of ANS modulation. This study provides not only physiologic evidence for the modulation effects of deep touch pressure on stressful conditions in dental environments but also the evidence that the application of papoose board, as a sensory adaptation technique, is not harmful for dental patients with special needs. Copyright © 2012. Published by Elsevier B.V.

Children Are Not Little Adults!

EPA Pesticide Factsheets

They are often more likely to be at risk from environmental hazards because of unique activity patterns/behavior, physiological differences, and windows of susceptibility during early lifestages including fetal development and puberty.

Physiological changes in fast and slow muscle with simulated weightlessness

NASA Technical Reports Server (NTRS)

Dettbarn, W. D.; Misulis, K. E.

1984-01-01

A rat hindlimb suspension model of simulated weightlessness was used to examine the physiological characteristics of skeletal muscle. The physiological sequelae of hindlimb suspension were compared to those of spinal cord section, denervation by sciatic nerve crush, and control. Muscle examined were the predominantly slow (Type 1) soleus (SOL) and the predominantly fast (Type 2) extensor digitorum longus (EDL). Two procedures which alter motor unit activity, hindlimb suspension and spinal cord section, produce changes in characteristics of skeletal muscles that are dependent upon fiber type. The SOL develops characteristics more representative of a fast muscle, including smaller Type 1 fiber proportion and higher AChE activity. The EDL, which is already predominantly fast, loses most of its few Type 1 fibers, thus also becoming faster. These data are in agreement with the studies in which rats experienced actual weightlessness.

Inducible Knockout of the Cyclin-Dependent Kinase 5 Activator p35 Alters Hippocampal Spatial Coding and Neuronal Excitability

PubMed Central

Kamiki, Eriko; Boehringer, Roman; Polygalov, Denis; Ohshima, Toshio; McHugh, Thomas J.

2018-01-01

p35 is an activating co-factor of Cyclin-dependent kinase 5 (Cdk5), a protein whose dysfunction has been implicated in a wide-range of neurological disorders including cognitive impairment and disease. Inducible deletion of the p35 gene in adult mice results in profound deficits in hippocampal-dependent spatial learning and synaptic physiology, however the impact of the loss of p35 function on hippocampal in vivo physiology and spatial coding remains unknown. Here, we recorded CA1 pyramidal cell activity in freely behaving p35 cKO and control mice and found that place cells in the mutant mice have elevated firing rates and impaired spatial coding, accompanied by changes in the temporal organization of spiking both during exploration and rest. These data shed light on the role of p35 in maintaining cellular and network excitability and provide a physiological correlate of the spatial learning deficits in these mice. PMID:29867369

Energetics, adaptation, and adaptability.

PubMed

Ulijaszek, Stanley J

1996-01-01

Energy capture and conversion are fundamental to human existence, and over the past three decades biological anthropologists have used a number of approaches which incorporate energetics measures in studies of human population biology. Human groups can vary enormously in their energy expenditure. This review considers evidence for genetic adaptation and presents models for physiological adaptability to reduced physiological energy availability and/or negative energy balance. In industrialized populations, different aspects of energy expenditure have been shown to have a genetic component, including basal metabolic rate, habitual physical activity level, mechanical efficiency of work performance, and thermic effect of food. Metabolic adaptation to low energy intakes has been demonstrated in populations in both developing and industrialized nations. Thyroid hormone-related effects on energy metabolic responses to low physiological energy availability are unified in a model, linking energetic adaptability in physical activity and maintenance metabolism. Negative energy balance has been shown to be associated with reduced reproductive function in women experiencing seasonal environments in some developing countries. Existing models relating negative energy balance to menstrual or ovulatory function are largely descriptive, and do not propose any physiological mechanisms for this phenomenon. A model is proposed whereby reduced physiological energy availability could influence ovulatory function via low serum levels of the amino acid aspartate and reduced sympathetic nervous system activity. © 1996 Wiley-Liss, Inc. Copyright © 1996 Wiley-Liss, Inc.

Physiological adaptations to weight loss and factors favouring weight regain

PubMed Central

Greenway, F L

2015-01-01

Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (for example, improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homoeostatic, environmental and behavioural factors. In homoeostatic regulation, the hypothalamus has a central role in integrating signals regarding food intake, energy balance and body weight, while an ‘obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered, including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homoeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their efforts to achieve and maintain weight loss. PMID:25896063

Physiological and Transcriptional Responses of Different Industrial Microbes at Near-Zero Specific Growth Rates.

PubMed

Ercan, Onur; Bisschops, Markus M M; Overkamp, Wout; Jørgensen, Thomas R; Ram, Arthur F; Smid, Eddy J; Pronk, Jack T; Kuipers, Oscar P; Daran-Lapujade, Pascale; Kleerebezem, Michiel

2015-09-01

The current knowledge of the physiology and gene expression of industrially relevant microorganisms is largely based on laboratory studies under conditions of rapid growth and high metabolic activity. However, in natural ecosystems and industrial processes, microbes frequently encounter severe calorie restriction. As a consequence, microbial growth rates in such settings can be extremely slow and even approach zero. Furthermore, uncoupling microbial growth from product formation, while cellular integrity and activity are maintained, offers perspectives that are economically highly interesting. Retentostat cultures have been employed to investigate microbial physiology at (near-)zero growth rates. This minireview compares information from recent physiological and gene expression studies on retentostat cultures of the industrially relevant microorganisms Lactobacillus plantarum, Lactococcus lactis, Bacillus subtilis, Saccharomyces cerevisiae, and Aspergillus niger. Shared responses of these organisms to (near-)zero growth rates include increased stress tolerance and a downregulation of genes involved in protein synthesis. Other adaptations, such as changes in morphology and (secondary) metabolite production, were species specific. This comparison underlines the industrial and scientific significance of further research on microbial (near-)zero growth physiology. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Daily Physical Activity and Hot Flashes in the Study of Women's Health Across the Nation FLASHES Study

PubMed Central

Gibson, Carolyn; Matthews, Karen; Thurston, Rebecca

2014-01-01

Objective To examine the role of physical activity in menopausal hot flashes. Competing models conceptualize physical activity as a risk or protective factor for hot flashes. Few studies have examined this relationship prospectively using physiologic measures of hot flashes and physical activity. Design Over two 48 hour-periods, 51 participants wore a physiologic hot flash monitor and activity monitor, and reported their hot flashes in an electronic diary. Physiologic hot flashes, reported hot flashes and reported hot flashes without physiological corroboration were related to activity changes using hierarchical generalized linear modeling, adjusting for potential confounders. Setting Community. Patients Midlife women. Interventions None. Main Outcome Measures Physiologically-detected hot flashes and reported hot flashes with and without physiologic corroboration. Results Hot flash reports without physiologic corroboration were more likely after activity increases (OR 1.04, 95% CI: 1.00-1.10, p=.01), particularly among women with higher levels of depressive symptoms (interaction p=.02). No other types of hot flashes were related to physical activity. Conclusion Acute increases in physical activity were associated with increased reporting of hot flashes lacking physiologic corroboration, particularly among women with depressive symptoms. Clinicians should consider the role of symptom perception and reporting in relations between physical activity and hot flashes. PMID:24491454

Physiological Factors Contributing to Postflight Changes in Functional Performance

NASA Technical Reports Server (NTRS)

Bloomberg, J. J.; Feedback, D. L.; Feiverson, A. H.; Lee, S. M. C.; Mulavara, A. P.; Peters, B. T.; Platts, S. H.; Reschke, M. F.; Ryder, J.; Spiering, B. A.;

A new engineering approach to reveal correlation of physiological change and spontaneous expression from video images

NASA Astrophysics Data System (ADS)

Yang, Fenglei; Hu, Sijung; Ma, Xiaoyun; Hassan, Harnani; Wei, Dongqing

2015-03-01

Spontaneous expression is associated with physiological states, i.e., heart rate, respiration, oxygen saturation (SpO2%), and heart rate variability (HRV). There have yet not sufficient efforts to explore correlation of physiological change and spontaneous expression. This study aims to study how spontaneous expression is associated with physiological changes with an approved protocol or through the videos provided from Denver Intensity of Spontaneous Facial Action Database. Not like a posed expression, motion artefact in spontaneous expression is one of evitable challenges to be overcome in the study. To obtain a physiological signs from a region of interest (ROI), a new engineering approach is being developed with an artefact-reduction method consolidated 3D active appearance model (AAM) based track, affine transformation based alignment with opto-physiological mode based imaging photoplethysmography. Also, a statistical association spaces is being used to interpret correlation of spontaneous expressions and physiological states including their probability densities by means of Gaussian Mixture Model. The present work is revealing a new avenue of study associations of spontaneous expressions and physiological states with its prospect of applications on physiological and psychological assessment.

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.

Comparative and integrative metabolomics reveal that S-nitrosation inhibits physiologically relevant metabolic enzymes.

PubMed

Bruegger, Joel J; Smith, Brian C; Wynia-Smith, Sarah L; Marletta, Michael A

2018-04-27

Cysteine S -nitrosation is a reversible post-translational modification mediated by nitric oxide ( • NO)-derived agents. S -Nitrosation participates in cellular signaling and is associated with several diseases such as cancer, cardiovascular diseases, and neuronal disorders. Despite the physiological importance of this nonclassical • NO-signaling pathway, little is understood about how much S -nitrosation affects protein function. Moreover, identifying physiologically relevant targets of S -nitrosation is difficult because of the dynamics of transnitrosation and a limited understanding of the physiological mechanisms leading to selective protein S -nitrosation. To identify proteins whose activities are modulated by S -nitrosation, we performed a metabolomics study comparing WT and endothelial nitric-oxide synthase knockout mice. We integrated our results with those of a previous proteomics study that identified physiologically relevant S -nitrosated cysteines, and we found that the activity of at least 21 metabolic enzymes might be regulated by S -nitrosation. We cloned, expressed, and purified four of these enzymes and observed that S -nitrosation inhibits the metabolic enzymes 6-phosphogluconate dehydrogenase, Δ1-pyrroline-5-carboxylate dehydrogenase, catechol- O -methyltransferase, and d-3-phosphoglycerate dehydrogenase. Furthermore, using site-directed mutagenesis, we identified the predominant cysteine residue influencing the observed activity changes in each enzyme. In summary, using an integrated metabolomics approach, we have identified several physiologically relevant S -nitrosation targets, including metabolic enzymes, which are inhibited by this modification, and we have found the cysteines modified by S -nitrosation in each enzyme. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

75 FR 20603 - Agency Information Collection Activities; Proposed Collection; Comment Request; Tobacco Health...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-20

... granted FDA important new authority to regulate the manufacture, marketing, and distribution of tobacco..., behavioral, or physiologic effects of current or future tobacco products, their constituents (including smoke...

Identification of proteins involved in desiccation tolerance in the red seaweed Pyropia orbicularis (Rhodophyta, Bangiales).

PubMed

López-Cristoffanini, Camilo; Zapata, Javier; Gaillard, Fanny; Potin, Philippe; Correa, Juan A; Contreras-Porcia, Loretto

2015-12-01

Extreme reduction in cellular water content leads to desiccation, which, if persistent, affects the physiology of organisms, mainly through oxidative stress. Some organisms are highly tolerant to desiccation, including resurrection plants and certain intertidal seaweeds. One such species is Pyropia orbicularis, a rhodophycean that colonizes upper intertidal zones along the Chilean coast. Despite long, daily periods of air exposure due to tides, this alga is highly tolerant to desiccation. The present study examined the proteome of P. orbicularis by 2DE and LC-MS/MS analyses to determine the proteins associated with desiccation tolerance (DT). The results showed that, under natural conditions, there were significant changes in the protein profile during low tide as compared to naturally hydrated plants at high tide. These changes were mainly in newly appeared proteins spots such as chaperones, monodehydroascorbate reductase, and manganese superoxide dismutase, among others. Previously undescribed proteins under desiccation conditions included phycobiliproteins, glyoxalase I, and phosphomannomutase. These changes evidenced that several physiological responses involved in DT are activated during low tide, including decreased photosynthetic activity, increased antioxidant capacity, and the preservation of cell physiology by regulating water content, cell wall structure, and cell volume. Similar responses have been observed in resurrection plants and bryophytes exposed to desiccation. Therefore, the coordinated activation of different desiccation tolerance pathways in P. orbicularis could explain the successful biological performance of this seaweed in the upper intertidal rocky zones. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Performance in physiology evaluation: possible improvement by active learning strategies.

PubMed

Montrezor, Luís H

2016-12-01

The evaluation process is complex and extremely important in the teaching/learning process. Evaluations are constantly employed in the classroom to assist students in the learning process and to help teachers improve the teaching process. The use of active methodologies encourages students to participate in the learning process, encourages interaction with their peers, and stimulates thinking about physiological mechanisms. This study examined the performance of medical students on physiology over four semesters with and without active engagement methodologies. Four activities were used: a puzzle, a board game, a debate, and a video. The results show that engaging in activities with active methodologies before a physiology cognitive monitoring test significantly improved student performance compared with not performing the activities. We integrate the use of these methodologies with classic lectures, and this integration appears to improve the teaching/learning process in the discipline of physiology and improves the integration of physiology with cardiology and neurology. In addition, students enjoy the activities and perform better on their evaluations when they use them. Copyright © 2016 The American Physiological Society.

Minireview: The Year in Review of Estrogen Regulation of Metabolism

PubMed Central

2012-01-01

Gonadal steroids are critical regulators of physiology, yet we approach physiology and science with the simplest perspective/model, the male one. Female models of whole animal physiology are complex to study and, therefore, are often not used in research. Estrogens are one of the sex hormones that we know are important for both men and women. Estrogens regulate key features of metabolism such as food intake, body weight, glucose homeostasis/insulin sensitivity, body fat distribution, lipolysis/lipogenesis, inflammation, locomotor activity, energy expenditure, reproduction, and cognition. Furthermore, estrogens have multiple sites of action including some unexpected ones, which was demonstrated elegantly through a series of papers this year. PMID:23051593

Enzymatic Activity of Free-Prostate-Specific Antigen (f-PSA) Is Not Required for Some of its Physiological Activities

PubMed Central

Chadha, Kailash C.; Nair, Bindukumar B.; Chakravarthi, Srikant; Zhou, Rita; Godoy, Alejandro; Mohler, James L.; Aalinkeel, Ravikumar; Schwartz, Stanley A.; Smith, Gary J.

2015-01-01

BACKGROUND Prostate specific antigen (PSA) is a well known biomarker for early diagnosis and management of prostate cancer. Furthermore, PSA has been documented to have anti-angiogenic and anti-tumorigenic activities in both in vitro and in vivo studies. However, little is known about the molecular mechanism(s) involved in regulation of these processes, in particular the role of the serine-protease enzymatic activity of PSA. METHODS Enzymatic activity of PSA isolated directly from seminal plasma was inhibited specifically (>95%) by incubation with zinc2+. Human umbilical vein endothelial cells (HUVEC) were utilized to compare/contrast the physiological effects of enzymatically active versus inactive PSA. RESULTS Equimolar concentrations of enzymatically active PSA and PSA enzymatically inactivated by incubation with Zn2+ had similar physiological effects on HUVEC, including inhibiting the gene expression of pro-angiogenic growth factors, like VEGF and bFGF, and up-regulation of expression of the anti-angiogenic growth factor IFN-γ; suppression of mRNA expression for markers of blood vessel development, like FAK, FLT, KDR, TWIST-1; P-38; inhibition of endothelial tube formation in the in vitro Matrigel Tube Formation Assay; and inhibition of endothelial cell invasion and migration properties. DISCUSSION Our data provides compelling evidence that the transcriptional regulatory and the anti-angiogenic activities of human PSA are independent of the innate enzymatic activity PMID:21446007

Are fish immune systems really affected by parasites? an immunoecological study of common carp (Cyprinus carpio)

PubMed Central

2011-01-01

Background The basic function of the immune system is to protect an organism against infection in order to minimize the fitness costs of being infected. According to life-history theory, energy resources are in a trade-off between the costly demands of immunity and other physiological demands. Concerning fish, both physiology and immunity are influenced by seasonal changes (i.e. temporal variation) associated to the changes of abiotic factors (such as primarily water temperature) and interactions with pathogens and parasites. In this study, we investigated the potential associations between the physiology and immunocompetence of common carp (Cyprinus carpio) collected during five different periods of a given year. Our sampling included the periods with temporal variability and thus, it presented a different level in exposure to parasites. We analyzed which of two factors, seasonality or parasitism, had the strongest impact on changes in fish physiology and immunity. Results We found that seasonal changes play a key role in affecting the analyzed measurements of physiology, immunity and parasitism. The correlation analysis revealed the relationships between the measures of overall host physiology, immunity and parasite load when temporal variability effect was removed. When analyzing separately parasite groups with different life-strategies, we found that fish with a worse condition status were infected more by monogeneans, representing the most abundant parasite group. The high infection by cestodes seems to activate the phagocytes. A weak relationship was found between spleen size and abundance of trematodes when taking into account seasonal changes. Conclusions Even if no direct trade-off between the measures of host immunity and physiology was confirmed when taking into account the seasonality, it seems that seasonal variability affects host immunity and physiology through energy allocation in a trade-off between life important functions, especially reproduction and fish condition. Host immunity measures were not found to be in a trade-off with the investigated physiological traits or functions, but we confirmed the immunosuppressive role of 11-ketotestosterone on fish immunity measured by complement activity. We suggest that the different parasite life-strategies influence different aspects of host physiology and activate the different immunity pathways. PMID:21708010

Learning through the Ages: How We Grow Old.

ERIC Educational Resources Information Center

Blystone, Robert V.; And Others

1988-01-01

Provides suggestions for a unit on the biological process of aging. Includes three activity sheets on the comparison of jaws and dentition from differently aged people, a denture survey, and eating and living without teeth. Includes a framework for organizing a course on the physiology of aging. (RT)

Space Resources for Teachers: Biology, Including Suggestions for Classroom Activities and Laboratory Experiments.

ERIC Educational Resources Information Center

Lee, Tom E.; And Others

This compilation of resource units concerns the latest developments in space biology. Some of the topics included are oxygen consumption, temperature, radiation, rhythms, weightlessness, acceleration and vibration stress, toxicity, and sensory and perceptual problems. Many of the topics are interdisciplinary and relate biology, physiology,…

Multiple functions of BCL-2 family proteins.

PubMed

Hardwick, J Marie; Soane, Lucian

2013-02-01

BCL-2 family proteins are the regulators of apoptosis, but also have other functions. This family of interacting partners includes inhibitors and inducers of cell death. Together they regulate and mediate the process by which mitochondria contribute to cell death known as the intrinsic apoptosis pathway. This pathway is required for normal embryonic development and for preventing cancer. However, before apoptosis is induced, BCL-2 proteins have critical roles in normal cell physiology related to neuronal activity, autophagy, calcium handling, mitochondrial dynamics and energetics, and other processes of normal healthy cells. The relative importance of these physiological functions compared to their apoptosis functions in overall organismal physiology is difficult to decipher. Apoptotic and noncanonical functions of these proteins may be intertwined to link cell growth to cell death. Disentanglement of these functions may require delineation of biochemical activities inherent to the characteristic three-dimensional shape shared by distantly related viral and cellular BCL-2 family members.

Adaptive biochemical and physiological responses of Eriobotrya japonica to fluoride air pollution.

PubMed

Elloumi, Nada; Zouari, Mohamed; Mezghani, Imed; Ben Abdallah, Ferjani; Woodward, Steve; Kallel, Monem

2017-09-01

The biochemical and physiological effects of fluoride were investigated in loquat trees (Eriobotrya japonica) grown in the vicinity of a phosphate fertilizer plant in Tunisia. Photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities were assessed; along with photosynthetic pigments, lipid peroxidation, electrolytic leakage (EL) and total phenolic contents in foliage and roots of trees at different distances from the phosphate fertilizer plant. All assessed parameters showed significant discrepancies in comparison with unpolluted sites. Obtained results showed high oxidative stress indices including H 2 O 2 , lipid peroxidation, and EL, SOD, CAT and GPx activities and proline contents in leaves and roots at the polluted sites as compared to control. In contrast, leaf Pn, Gs, E and photosynthetic pigment contents were low as compared to the control. These results indicate that even though antioxidant responses increased near the factory, adverse effects on physiology were pronounced.

Physiologic Measures of Animal Stress during Transitional States of Consciousness

PubMed Central

Meyer, Robert E.

2015-01-01

Simple Summary The humaneness, and therefore suitability, of any particular agent or method used to produce unconsciousness in animals, whether for anesthesia, euthanasia, humane slaughter, or depopulation, depends on the experience of pain or distress prior to loss of consciousness. Commonly reported physiologic measures of animal stress, including physical movement and vocalization, heart rate and ECG, electroencephalographic activity, and plasma and neuronal stress markers are discussed within this context. Abstract Determination of the humaneness of methods used to produce unconsciousness in animals, whether for anesthesia, euthanasia, humane slaughter, or depopulation, relies on our ability to assess stress, pain, and consciousness within the contexts of method and application. Determining the subjective experience of animals during transitional states of consciousness, however, can be quite difficult; further, loss of consciousness with different agents or methods may occur at substantially different rates. Stress and distress may manifest behaviorally (e.g., overt escape behaviors, approach-avoidance preferences [aversion]) or physiologically (e.g., movement, vocalization, changes in electroencephalographic activity, heart rate, sympathetic nervous system [SNS] activity, hypothalamic-pituitary axis [HPA] activity), such that a one-size-fits-all approach cannot be easily applied to evaluate methods or determine specific species applications. The purpose of this review is to discuss methods of evaluating stress in animals using physiologic methods, with emphasis on the transition between the conscious and unconscious states. PMID:26479382

2D and 3D Matrices to Study Linear Invadosome Formation and Activity.

PubMed

Di Martino, Julie; Henriet, Elodie; Ezzoukhry, Zakaria; Mondal, Chandrani; Bravo-Cordero, Jose Javier; Moreau, Violaine; Saltel, Frederic

2017-06-02

Cell adhesion, migration, and invasion are involved in many physiological and pathological processes. For example, during metastasis formation, tumor cells have to cross anatomical barriers to invade and migrate through the surrounding tissue in order to reach blood or lymphatic vessels. This requires the interaction between cells and the extracellular matrix (ECM). At the cellular level, many cells, including the majority of cancer cells, are able to form invadosomes, which are F-actin-based structures capable of degrading ECM. Invadosomes are protrusive actin structures that recruit and activate matrix metalloproteinases (MMPs). The molecular composition, density, organization, and stiffness of the ECM are crucial in regulating invadosome formation and activation. In vitro, a gelatin assay is the standard assay used to observe and quantify invadosome degradation activity. However, gelatin, which is denatured collagen I, is not a physiological matrix element. A novel assay using type I collagen fibrils was developed and used to demonstrate that this physiological matrix is a potent inducer of invadosomes. Invadosomes that form along the collagen fibrils are known as linear invadosomes due to their linear organization on the fibers. Moreover, molecular analysis of linear invadosomes showed that the discoidin domain receptor 1 (DDR1) is the receptor involved in their formation. These data clearly demonstrate the importance of using a physiologically relevant matrix in order to understand the complex interactions between cells and the ECM.

Effect of a puzzle on the process of students' learning about cardiac physiology.

PubMed

Cardozo, Lais Tono; Miranda, Aline Soares; Moura, Maria José Costa Sampaio; Marcondes, Fernanda Klein

2016-09-01

The aim of the present study was to evaluate the effects of using a puzzle to learn about cardiac physiology. Students were divided into control and game groups. In class 1, the control group had a 2-h theoretical class about cardiac physiology, including a detailed description of the phases of the cardiac cycle, whereas the game group had a 50-min theoretical class without the description of the cardiac cycle. In class 2, the control group did an assessment exercise before an activity with the cardiac puzzle and the game group answered questions after the above-mentioned activity. While solving the puzzle, the students had to describe the cardiac cycle by relating the concepts of heart morphology and physiology. To evaluate short-term learning, the number of wrong answers and grades in the assessment exercise were compared between the control and game groups. To evaluate medium-term learning, we compared the grades obtained by students of the control and game groups in questions about cardiac physiology that formed part of the academic exam. In the assessment exercise, the game group presented a lower number of errors and higher score compared with the control group. In the academic exam, applied after both groups had used the puzzle, there was no difference in the scores obtained by the control and game groups in questions about cardiac physiology. These results showed a positive effect of the puzzle on students' learning about cardiac physiology compared with those not using the puzzle. Copyright © 2016 The American Physiological Society.

The use of a running wheel to measure activity in rodents: relationship to energy balance, general activity, and reward.

PubMed

Novak, Colleen M; Burghardt, Paul R; Levine, James A

2012-03-01

Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems-including those related to the stress response, mood, and reward, and those responsive to growth factors-that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

The use of a running wheel to measure activity in rodents: Relationship to energy balance, general activity, and reward

PubMed Central

Levine, James A.

2015-01-01

Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems—including those related to the stress response, mood, and reward, and those responsive to growth factors—that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. PMID:22230703

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

An introduction to the 'Psycho-Physiological-Stress-Test' (PPST)-A standardized instrument for evaluating stress reactions.

PubMed

Neureiter, Elisabeth; Hajfani, Loreen; Ahnis, Anne; Mierke, Annett; Rose, Matthias; Danzer, Gerhard; Klapp, Burghard F

2017-01-01

Using a standardized instrument to evaluate patients' stress reactions has become more important in daily clinical routines. Different signs or symptoms of stress are often unilaterally explored: the physiological, psychological or social aspects of stress disorders are each viewed on a single dimension. However, all dimensions afflict patients who have persistent health problems due to chronic stress. Therefore, it is important to use a multidimensional approach to acquire data. The 'Psycho-Physiological-Stress-Test' (PPST) was established to achieve a comprehensive understanding of stress and was further developed at the Charité-Universitätsmedizin Berlin in collaboration with the Psychological Department of Freie Universität Berlin. The PPST includes a series of varying stress phases, embedded in two periods of rest. Physiological and psychological parameters are simultaneously measured throughout the test session. Specifically, the PPST activates the sympathetic stress axis, which is measured by heart rate, blood pressure, respiration depth and rate, electro dermal activation and muscle tension (frontalis, masseter, trapezius). Psychological data are simultaneously collected, and include performance, motivation, emotion and behavior. After conducting this diagnostic test, it is possible to identify individual stress patterns that can be discussed with the individual patient to develop and recommend (outpatient) treatment strategies. This paper introduces the PPST as a standardized way to evaluate stress reactions by presenting the results from a sample of psychosomatic inpatients (n = 139) who were treated in Charité-Universitätsmedizin Berlin, Germany. We observed that the varying testing conditions provoked adjusted changes in the different physiological parameters and psychological levels.

Identification of an immune-responsive mesolimbocortical serotonergic system: Potential role in regulation of emotional behavior

PubMed Central

Lowry, C.A.; Hollis, J.H.; de Vries, A.; Pan, B.; Brunet, L.R.; Hunt, J.R.F.; Paton, J.F.R.; van Kampen, E.; Knight, D.M.; Evans, A.K.; Rook, G.A.W.; Lightman, S.L.

2007-01-01

Peripheral immune activation can have profound physiological and behavioral effects including induction of fever and sickness behavior. One mechanism through which immune activation or immunomodulation may affect physiology and behavior is via actions on brainstem neuromodulatory systems, such as serotonergic systems. We have found that peripheral immune activation with antigens derived from the nonpathogenic, saprophytic bacterium, Mycobacterium vaccae, activated a specific subset of serotonergic neurons in the interfascicular part of the dorsal raphe nucleus (DRI) of mice, as measured by quantification of c-Fos expression following intratracheal (12 h) or s.c. (6 h) administration of heat-killed, ultrasonically disrupted M. vaccae, or heat-killed, intact M. vaccae, respectively. These effects were apparent after immune activation by M. vaccae or its components but not by ovalbumin, which induces a qualitatively different immune response. The effects of immune activation were associated with increases in serotonin metabolism within the ventromedial prefrontal cortex, consistent with an effect of immune activation on mesolimbocortical serotonergic systems. The effects of M. vaccae administration on serotonergic systems were temporally associated with reductions in immobility in the forced swim test, consistent with the hypothesis that the stimulation of mesolimbocortical serotonergic systems by peripheral immune activation alters stress-related emotional behavior. These findings suggest that the immune-responsive subpopulation of serotonergic neurons in the DRI is likely to play an important role in the neural mechanisms underlying regulation of the physiological and pathophysiological responses to both acute and chronic immune activation, including regulation of mood during health and disease states. Together with previous studies, these findings also raise the possibility that immune stimulation activates a functionally and anatomically distinct subset of serotonergic neurons, different from the subset of serotonergic neurons activated by anxiogenic stimuli or uncontrollable stressors. Consequently, selective activation of specific subsets of serotonergic neurons may have distinct behavioral outcomes. PMID:17367941

Multimodal Regulation of Circadian Glucocorticoid Rhythm by Central and Adrenal Clocks.

PubMed

Son, Gi Hoon; Cha, Hyo Kyeong; Chung, Sooyoung; Kim, Kyungjin

2018-05-01

Adrenal glucocorticoids (GCs) control a wide range of physiological processes, including metabolism, cardiovascular and pulmonary activities, immune and inflammatory responses, and various brain functions. During stress responses, GCs are secreted through activation of the hypothalamic-pituitary-adrenal axis, whereas circulating GC levels in unstressed states follow a robust circadian oscillation with a peak around the onset of the active period of a day. A recent advance in chronobiological research has revealed that multiple regulatory mechanisms, along with classical neuroendocrine regulation, underlie this GC circadian rhythm. The hierarchically organized circadian system, with a central pacemaker in the suprachiasmatic nucleus of the hypothalamus and local oscillators in peripheral tissues, including the adrenal gland, mediates periodicities in physiological processes in mammals. In this review, we primarily focus on our understanding of the circadian regulation of adrenal GC rhythm, with particular attention to the cooperative actions of the suprachiasmatic nucleus central and adrenal local clocks, and the clinical implications of this rhythm in human diseases.

Multimodal Regulation of Circadian Glucocorticoid Rhythm by Central and Adrenal Clocks

PubMed Central

Son, Gi Hoon; Cha, Hyo Kyeong; Chung, Sooyoung; Kim, Kyungjin

2018-01-01

Abstract Adrenal glucocorticoids (GCs) control a wide range of physiological processes, including metabolism, cardiovascular and pulmonary activities, immune and inflammatory responses, and various brain functions. During stress responses, GCs are secreted through activation of the hypothalamic–pituitary–adrenal axis, whereas circulating GC levels in unstressed states follow a robust circadian oscillation with a peak around the onset of the active period of a day. A recent advance in chronobiological research has revealed that multiple regulatory mechanisms, along with classical neuroendocrine regulation, underlie this GC circadian rhythm. The hierarchically organized circadian system, with a central pacemaker in the suprachiasmatic nucleus of the hypothalamus and local oscillators in peripheral tissues, including the adrenal gland, mediates periodicities in physiological processes in mammals. In this review, we primarily focus on our understanding of the circadian regulation of adrenal GC rhythm, with particular attention to the cooperative actions of the suprachiasmatic nucleus central and adrenal local clocks, and the clinical implications of this rhythm in human diseases. PMID:29713692

Progress in the field of physiologically active lanosterol compounds

NASA Astrophysics Data System (ADS)

Reshetova, I. G.; Tkhaper, R. K.; Kamernitskii, Alexey V.

1992-08-01

This review correlates the studies (up to 1991) on the isolation, structural determination, biological activity, and synthesis of physiologically active polyoxidised lanosterol derivatives of vegetable (inotodiol, ganoderic acids) and animal (seychellogenin) origin. The cytotoxic, cardiovascular, and other forms of activity of compounds of this type are of considerable interest in relation to their medical use. It is noted that the functionalised side chain (in an open form or containing lactones, lactols, etc.) is generally responsible for the activity exhibited by lanosterol derivatives. Two basic approaches to the derivation of these structures are defined: either by complete reconstruction of the side chain of lanosterol (degradation and rebuilding with oxygen-containing residues) or by progressive functionalisation of the Δ24-side chain of lanosterol. The synthesis of the known anticancer compound "inotodiol", seychellogenins, ganoderic acids, and other compounds are described. The bibliography includes 105 references.

Antarctic emerald rockcod have the capacity to compensate for warming when uncoupled from CO2 -acidification.

PubMed

Davis, Brittany E; Flynn, Erin E; Miller, Nathan A; Nelson, Frederick A; Fangue, Nann A; Todgham, Anne E

2018-02-01

Increases in atmospheric CO 2 levels and associated ocean changes are expected to have dramatic impacts on marine ecosystems. Although the Southern Ocean is experiencing some of the fastest rates of change, few studies have explored how Antarctic fishes may be affected by co-occurring ocean changes, and even fewer have examined early life stages. To date, no studies have characterized potential trade-offs in physiology and behavior in response to projected multiple climate change stressors (ocean acidification and warming) on Antarctic fishes. We exposed juvenile emerald rockcod Trematomus bernacchii to three PCO 2 treatments (~450, ~850, and ~1,200 μatm PCO 2 ) at two temperatures (-1 or 2°C). After 2, 7, 14, and 28 days, metrics of physiological performance including cardiorespiratory function (heart rate [f H ] and ventilation rate [f V ]), metabolic rate (M˙O2), and cellular enzyme activity were measured. Behavioral responses, including scototaxis, activity, exploration, and escape response were assessed after 7 and 14 days. Elevated PCO 2 independently had little impact on either physiology or behavior in juvenile rockcod, whereas warming resulted in significant changes across acclimation time. After 14 days, f H , f V and M˙O2 significantly increased with warming, but not with elevated PCO 2 . Increased physiological costs were accompanied by behavioral alterations including increased dark zone preference up to 14%, reduced activity by 12%, as well as reduced escape time suggesting potential trade-offs in energetics. After 28 days, juvenile rockcod demonstrated a degree of temperature compensation as f V , M˙O2, and cellular metabolism significantly decreased following the peak at 14 days; however, temperature compensation was only evident in the absence of elevated PCO 2 . Sustained increases in f V and M˙O2 after 28 days exposure to elevated PCO 2 indicate additive (f V ) and synergistic (M˙O2) interactions occurred in combination with warming. Stressor-induced energetic trade-offs in physiology and behavior may be an important mechanism leading to vulnerability of Antarctic fishes to future ocean change. © 2017 John Wiley & Sons Ltd.

A BK (Slo1) channel journey from molecule to physiology

PubMed Central

Contreras, Gustavo F; Castillo, Karen; Enrique, Nicolás; Carrasquel-Ursulaez, Willy; Castillo, Juan Pablo; Milesi, Verónica; Neely, Alan; Alvarez, Osvaldo; Ferreira, Gonzalo; González, Carlos; Latorre, Ramón

2013-01-01

Calcium and voltage-activated potassium (BK) channels are key actors in cell physiology, both in neuronal and non-neuronal cells and tissues. Through negative feedback between intracellular Ca2+ and membrane voltage, BK channels provide a damping mechanism for excitatory signals. Molecular modulation of these channels by alternative splicing, auxiliary subunits and post-translational modifications showed that these channels are subjected to many mechanisms that add diversity to the BK channel α subunit gene. This complexity of interactions modulates BK channel gating, modifying the energetic barrier of voltage sensor domain activation and channel opening. Regions for voltage as well as Ca2+ sensitivity have been identified, and the crystal structure generated by the 2 RCK domains contained in the C-terminal of the channel has been described. The linkage of these channels to many intracellular metabolites and pathways, as well as their modulation by extracellular natural agents, has been found to be relevant in many physiological processes. This review includes the hallmarks of BK channel biophysics and its physiological impact on specific cells and tissues, highlighting its relationship with auxiliary subunit expression. PMID:24025517

Advanced EVA system design requirements study

NASA Technical Reports Server (NTRS)

1986-01-01

Design requirements and criteria for the Space Station Advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related extravehicular activity (EVA) support equipment were defined and established. The EVA mission requirements, environments, and medical and physiological requirements, as well as opertional, procedures, and training issues were considered.

POLYBROMINATED DEPHENYL ETHERS (PBDES) AND ORTHO-SUBSTITUTED POLYCHLORINATED BIPHENYLS (PCBS) AS NEUROENDOCRINE DISRUPTORS OF VASOPRESSIN RELEASE: EFFECTS DURING PHYSIOLOGICAL ACTIVATION IN VITRO AND STRUCTURE-ACTIVITY RELATIONSHIPS

EPA Science Inventory

The neuropeptide, vasopressin (VP) is synthesized in magnocellular neuroendocrine cells (MNCs) located within the supraoptic (SON) and paraventricular (PVN) nuclei of the mammalian hypothalamus. VP has multiple functions including maintenance of body fluid homeostasis, cardiovasc...

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

Quantitative modeling of multiscale neural activity

NASA Astrophysics Data System (ADS)

Robinson, Peter A.; Rennie, Christopher J.

2007-01-01

The electrical activity of the brain has been observed for over a century and is widely used to probe brain function and disorders, chiefly through the electroencephalogram (EEG) recorded by electrodes on the scalp. However, the connections between physiology and EEGs have been chiefly qualitative until recently, and most uses of the EEG have been based on phenomenological correlations. A quantitative mean-field model of brain electrical activity is described that spans the range of physiological and anatomical scales from microscopic synapses to the whole brain. Its parameters measure quantities such as synaptic strengths, signal delays, cellular time constants, and neural ranges, and are all constrained by independent physiological measurements. Application of standard techniques from wave physics allows successful predictions to be made of a wide range of EEG phenomena, including time series and spectra, evoked responses to stimuli, dependence on arousal state, seizure dynamics, and relationships to functional magnetic resonance imaging (fMRI). Fitting to experimental data also enables physiological parameters to be infered, giving a new noninvasive window into brain function, especially when referenced to a standardized database of subjects. Modifications of the core model to treat mm-scale patchy interconnections in the visual cortex are also described, and it is shown that resulting waves obey the Schroedinger equation. This opens the possibility of classical cortical analogs of quantum phenomena.

Porifera Lectins: Diversity, Physiological Roles and Biotechnological Potential.

PubMed

Gardères, Johan; Bourguet-Kondracki, Marie-Lise; Hamer, Bojan; Batel, Renato; Schröder, Heinz C; Müller, Werner E G

2015-08-07

An overview on the diversity of 39 lectins from the phylum Porifera is presented, including 38 lectins, which were identified from the class of demosponges, and one lectin from the class of hexactinellida. Their purification from crude extracts was mainly performed by using affinity chromatography and gel filtration techniques. Other protocols were also developed in order to collect and study sponge lectins, including screening of sponge genomes and expression in heterologous bacterial systems. The characterization of the lectins was performed by Edman degradation or mass spectrometry. Regarding their physiological roles, sponge lectins showed to be involved in morphogenesis and cell interaction, biomineralization and spiculogenesis, as well as host defense mechanisms and potentially in the association between the sponge and its microorganisms. In addition, these lectins exhibited a broad range of bioactivities, including modulation of inflammatory response, antimicrobial and cytotoxic activities, as well as anticancer and neuromodulatory activity. In view of their potential pharmacological applications, sponge lectins constitute promising molecules of biotechnological interest.

Porifera Lectins: Diversity, Physiological Roles and Biotechnological Potential

PubMed Central

Gardères, Johan; Bourguet-Kondracki, Marie-Lise; Hamer, Bojan; Batel, Renato; Schröder, Heinz C.; Müller, Werner E. G.

2015-01-01

An overview on the diversity of 39 lectins from the phylum Porifera is presented, including 38 lectins, which were identified from the class of demosponges, and one lectin from the class of hexactinellida. Their purification from crude extracts was mainly performed by using affinity chromatography and gel filtration techniques. Other protocols were also developed in order to collect and study sponge lectins, including screening of sponge genomes and expression in heterologous bacterial systems. The characterization of the lectins was performed by Edman degradation or mass spectrometry. Regarding their physiological roles, sponge lectins showed to be involved in morphogenesis and cell interaction, biomineralization and spiculogenesis, as well as host defense mechanisms and potentially in the association between the sponge and its microorganisms. In addition, these lectins exhibited a broad range of bioactivities, including modulation of inflammatory response, antimicrobial and cytotoxic activities, as well as anticancer and neuromodulatory activity. In view of their potential pharmacological applications, sponge lectins constitute promising molecules of biotechnological interest. PMID:26262628

Functional diversity of voltage-sensing phosphatases in two urodele amphibians.

PubMed

Mutua, Joshua; Jinno, Yuka; Sakata, Souhei; Okochi, Yoshifumi; Ueno, Shuichi; Tsutsui, Hidekazu; Kawai, Takafumi; Iwao, Yasuhiro; Okamura, Yasushi

2014-07-16

Voltage-sensing phosphatases (VSPs) share the molecular architecture of the voltage sensor domain (VSD) with voltage-gated ion channels and the phosphoinositide phosphatase region with the phosphatase and tensin homolog (PTEN), respectively. VSPs enzymatic activities are regulated by the motions of VSD upon depolarization. The physiological role of these proteins has remained elusive, and insights may be gained by investigating biological variations in different animal species. Urodele amphibians are vertebrates with potent activities of regeneration and also show diverse mechanisms of polyspermy prevention. We cloned cDNAs of VSPs from the testes of two urodeles; Hynobius nebulosus and Cynops pyrrhogaster, and compared their expression and voltage-dependent activation. Their molecular architecture is highly conserved in both Hynobius VSP (Hn-VSP) and Cynops VSP (Cp-VSP), including the positively-charged arginine residues in the S4 segment of the VSD and the enzymatic active site for substrate binding, yet the C-terminal C2 domain of Hn-VSP is significantly shorter than that of Cp-VSP and other VSP orthologs. RT-PCR analysis showed that gene expression pattern was distinct between two VSPs. The voltage sensor motions and voltage-dependent phosphatase activities were investigated electrophysiologically by expression in Xenopus oocytes. Both VSPs showed "sensing" currents, indicating that their voltage sensor domains are functional. The phosphatase activity of Cp-VSP was found to be voltage dependent, as shown by its ability to regulate the conductance of coexpressed GIRK2 channels, but Hn-VSP lacked such phosphatase activity due to the truncation of its C2 domain. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Salinity Tolerance Mechanism of Economic Halophytes From Physiological to Molecular Hierarchy for Improving Food Quality

PubMed Central

Xu, Chongzhi; Tang, Xiaoli; Shao, Hongbo; Wang, Hongyan

2016-01-01

Soil salinity is becoming the key constraints factor to agricultural production. Therefore, the plant especially the crops possessing capacities of salt tolerance will be of great economic significance. The adaptation or tolerance of plant to salinity stress involves a series of physiological, metabolic and molecular mechanisms. Halophytes are the kind of organisms which acquire special salt tolerance mechanisms to respond to the salt tress and ensure normal growth and development under saline conditions in their lengthy evolutionary adaptation, so understanding how halophytes respond to salinity stress will provide us with methods and tactics to foster and develop salt resistant varieties of crops. The strategies in physiological and molecular level adopted by halophytes are various including the changes in photosynthetic and transpiration rate, the sequestration of Na+ to extracellular or vacuole, the regulation of stomata aperture and stomatal density, the accumulation and synthesis of the phytohormones as well as the relevant gene expression underlying these physiological traits, such as the stress signal transduction, the regulation of the transcription factors, the activation and expression of the transporter genes, the activation or inhibition of the synthetases and so on. This review focuses on the research advances of the regulating mechanisms in halophytes from physiological to molecular, which render the halophytes tolerance and adaption to salinity stress. PMID:27252587

Worker honeybee sterility: a proteomic analysis of suppressed ovary activation.

PubMed

Cardoen, Dries; Ernst, Ulrich R; Boerjan, Bart; Bogaerts, Annelies; Formesyn, Ellen; de Graaf, Dirk C; Wenseleers, Tom; Schoofs, Liliane; Verleyen, Peter

2012-05-04

Eusocial behavior is extensively studied in the honeybee, Apis mellifera, as it displays an extreme form of altruism. Honeybee workers are generally obligatory sterile in a bee colony headed by a queen, but the inhibition of ovary activation is lifted upon the absence of queen and larvae. Worker bees are then able to develop mature, viable eggs. The detailed repressive physiological mechanisms that are responsible for this remarkable phenomenon are as of yet largely unknown. Physiological studies today mainly focus on the transcriptome, while the proteome stays rather unexplored. Here, we present a quantitative 2-dimensional differential gel electrophoresis comparison between activated and inactivated worker ovaries and brains of reproductive and sterile worker bees, including a spot map of ovaries, containing 197 identified spots. Our findings suggest that suppression of ovary activation might involve a constant interplay between primordial oogenesis and subsequent degradation, which is probably mediated through steroid and neuropeptide hormone signaling. Additionally, the observation of higher viral protein loads in both the brains and ovaries of sterile workers is particularly noteworthy. This data set will be of great value for future research unraveling the physiological mechanisms underlying the altruistic sterility in honeybee workers.

Altered Gravity Simulated by Parabolic Flight and Water Immersion Leads to Decreased Trunk Motion

PubMed Central

Tian, Yu; Li, Fan; Zhang, Shaoyao; Zhang, Lin; Guo, Yaoyu; Liu, Weibo; Wang, Chunhui; Chen, Shanguang; Guo, Jinhu

2015-01-01

Gravity is one of the important environmental factors that influence the physiologies and behaviors of animals and humans, and changes in gravity elicit a variety of physiological and behavioral alterations that include impaired movement coordination, vertigo, spatial disorientation, and perceptual illusions. To elucidate the effects of gravity on human physiology and behavior, we examined changes in wrist and trunk activities and heart rate during parabolic flight and the activity of wrist and trunk in water immersion experiments. Data from 195 person-time parabolas performed by eight subjects revealed that the trunk motion counts decreased by approximately half during ascending legs (hypergravity), relative to the data acquired before the parabolic flights. In contrast, the wrist activity remained unchanged. The results from the water immersion experiments demonstrated that in the underwater condition, both the wrist and trunk activities were significantly decreased but the latter decreased to a much lower level. Together, these data suggest that gravitational alterations can result in differential influences on the motions of the wrist and the trunk. These findings might be important for understanding the degeneration of skeleton and muscular system and performance of astronauts in microgravity. PMID:26208253

Lowering Temperature is the Trigger for Glycogen Build-Up and Winter Fasting in Crucian Carp (Carassius carassius).

PubMed

Varis, Joonas; Haverinen, Jaakko; Vornanen, Matti

2016-02-01

Seasonal changes in physiology of vertebrate animals are triggered by environmental cues including temperature, day-length and oxygen availability. Crucian carp (Carassius carassius) tolerate prolonged anoxia in winter by using several physiological adaptations that are seasonally activated. This study examines which environmental cues are required to trigger physiological adjustments for winter dormancy in crucian carp. To this end, crucian carp were exposed to changing environmental factors under laboratory conditions: effects of declining water temperature, shortening day-length and reduced oxygen availability, separately and in different combinations, were examined on glycogen content and enzyme activities involved in feeding (alkaline phosphatase, AP) and glycogen metabolism (glycogen synthase, GyS; glycogen phosphorylase, GP). Lowering temperature induced a fall in activity of AP and a rise in glycogen content and rate of glycogen synthesis. Relative mass of the liver, and glycogen concentration of liver, muscle and brain increased with lowering temperature. Similarly activity of GyS in muscle and expression of GyS transcripts in brain were up-regulated by lowering temperature. Shortened day-length and oxygen availability had practically no effects on measured variables. We conclude that lowering temperature is the main trigger in preparation for winter anoxia in crucian carp.

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).

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.

Activation of cellular death programs associated with immunosenescence-like phenotype in TPPII knockout mice

PubMed Central

Huai, Jisen; Firat, Elke; Nil, Ahmed; Million, Daniele; Gaedicke, Simone; Kanzler, Benoit; Freudenberg, Marina; van Endert, Peter; Kohler, Gabriele; Pahl, Heike L.; Aichele, Peter; Eichmann, Klaus; Niedermann, Gabriele

2008-01-01

The giant cytosolic protease tripeptidyl peptidase II (TPPII) has been implicated in the regulation of proliferation and survival of malignant cells, particularly lymphoma cells. To address its functions in normal cellular and systemic physiology we have generated TPPII-deficient mice. TPPII deficiency activates cell type-specific death programs, including proliferative apoptosis in several T lineage subsets and premature cellular senescence in fibroblasts and CD8+ T cells. This coincides with up-regulation of p53 and dysregulation of NF-κB. Prominent degenerative alterations at the organismic level were a decreased lifespan and symptoms characteristic of immunohematopoietic senescence. These symptoms include accelerated thymic involution, lymphopenia, impaired proliferative T cell responses, extramedullary hematopoiesis, and inflammation. Thus, TPPII is important for maintaining normal cellular and systemic physiology, which may be relevant for potential therapeutic applications of TPPII inhibitors. PMID:18362329

Role of pigment epithelium-derived factor in the reproductive system.

PubMed

Chuderland, Dana; Ben-Ami, Ido; Bar-Joseph, Hadas; Shalgi, Ruth

2014-10-01

The physiological function of the female reproductive organs is hormonally controlled. In each cycle, the reproductive organs undergo tissue modifications that are accompanied by formation and destruction of blood vessels. Proper angiogenesis requires an accurate balance between stimulatory and inhibitory signals, provided by pro- and anti-angiogenic factors. As with many other tissues, vascular endothelial growth factor (VEGF) appears to be one of the major pro-angiogenic factors in the female reproductive organs. Pigment epithelium-derived factor (PEDF) is a non-inhibitory member of the serine protease inhibitors (serpin) superfamily, possessing potent physiologic anti-angiogenic activity that negates VEGF activity. The role of PEDF in decreasing abnormal neovascularization by exerting its anti-angiogenic effect that inhibits pro-angiogenic factors, including VEGF, has been investigated mainly in the eye and in cancer. This review summarizes the function of PEDF in the reproductive system, showing its hormonal regulation and its anti-angiogenic activity. Furthermore, some pathologies of the female reproductive organs, including endometriosis, ovarian hyperstimulation syndrome, polycystic ovary syndrome, and others, are associated with a faulty angiogenic process. This review illuminates the role of PEDF in their pathogenesis and treatment. Collectively, we can conclude that although PEDF seems to play an essential role in the physiology and pathophysiology of the reproductive system, its full role and mechanism of action still need to be elucidated. © 2014 Society for Reproduction and Fertility.

Thermal Infrared Imaging-Based Computational Psychophysiology for Psychometrics.

PubMed

Cardone, Daniela; Pinti, Paola; Merla, Arcangelo

2015-01-01

Thermal infrared imaging has been proposed as a potential system for the computational assessment of human autonomic nervous activity and psychophysiological states in a contactless and noninvasive way. Through bioheat modeling of facial thermal imagery, several vital signs can be extracted, including localized blood perfusion, cardiac pulse, breath rate, and sudomotor response, since all these parameters impact the cutaneous temperature. The obtained physiological information could then be used to draw inferences about a variety of psychophysiological or affective states, as proved by the increasing number of psychophysiological studies using thermal infrared imaging. This paper presents therefore a review of the principal achievements of thermal infrared imaging in computational physiology with regard to its capability of monitoring psychophysiological activity.

Semiconductor technology in protein kinase research and drug discovery: sensing a revolution.

PubMed

Bhalla, Nikhil; Di Lorenzo, Mirella; Estrela, Pedro; Pula, Giordano

2017-02-01

Since the discovery of protein kinase activity in 1954, close to 600 kinases have been discovered that have crucial roles in cell physiology. In several pathological conditions, aberrant protein kinase activity leads to abnormal cell and tissue physiology. Therefore, protein kinase inhibitors are investigated as potential treatments for several diseases, including dementia, diabetes, cancer and autoimmune and cardiovascular disease. Modern semiconductor technology has recently been applied to accelerate the discovery of novel protein kinase inhibitors that could become the standard-of-care drugs of tomorrow. Here, we describe current techniques and novel applications of semiconductor technologies in protein kinase inhibitor drug discovery. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kupffer Cell Metabolism and Function

PubMed Central

Nguyen-Lefebvre, Anh Thu; Horuzsko, Anatolij

2015-01-01

Kupffer cells are resident liver macrophages and play a critical role in maintaining liver functions. Under physiological conditions, they are the first innate immune cells and protect the liver from bacterial infections. Under pathological conditions, they are activated by different components and can differentiate into M1-like (classical) or M2-like (alternative) macrophages. The metabolism of classical or alternative activated Kupffer cells will determine their functions in liver damage. Special functions and metabolism of Kupffer cells suggest that they are an attractive target for therapy of liver inflammation and related diseases, including cancer and infectious diseases. Here we review the different types of Kupffer cells and their metabolism and functions in physiological and pathological conditions. PMID:26937490

Characteristics of hyperthermia-induced hyperventilation in humans

PubMed Central

Tsuji, Bun; Hayashi, Keiji; Kondo, Narihiko; Nishiyasu, Takeshi

2016-01-01

ABSTRACT In humans, hyperthermia leads to activation of a set of thermoregulatory responses that includes cutaneous vasodilation and sweating. Hyperthermia also increases ventilation in humans, as is observed in panting dogs, but the physiological significance and characteristics of the hyperventilatory response in humans remain unclear. The relative contribution of respiratory heat loss to total heat loss in a hot environment in humans is small, and this hyperventilation causes a concomitant reduction in arterial CO2 pressure (hypocapnia), which can cause cerebral hypoperfusion. Consequently, hyperventilation in humans may not contribute to the maintenance of physiological homeostasis (i.e., thermoregulation). To gain some insight into the physiological significance of hyperthermia-induced hyperventilation in humans, in this review, we discuss 1) the mechanisms underlying hyperthermia-induced hyperventilation, 2) the factors modulating this response, and 3) the physiological consequences of the response. PMID:27227102

Metal-containing Complexes of Lactams, Imidazoles, and Benzimidazoles and Their Biological Activity

NASA Astrophysics Data System (ADS)

Kukalenko, S. S.; Bovykin, B. A.; Shestakova, S. I.; Omel'chenko, A. M.

1985-07-01

The results of the latest investigations of the problem of the synthesis of metal-containing complexes of lactams, imidazoles, and benzimidazoles, their structure, and their stability in solutions are surveyed. Some data on their biological activity (pesticide and pharmacological) and the mechanism of their physiological action are presented. The bibliography includes 190 references.

Position of the American Dietetic Association: functional foods.

PubMed

Hasler, Clare M; Brown, Amy C

2009-04-01

All foods are functional at some physiological level, but it is the position of the American Dietetic Association (ADA) that functional foods that include whole foods and fortified, enriched, or enhanced foods have a potentially beneficial effect on health when consumed as part of a varied diet on a regular basis, at effective levels. ADA supports research to further define the health benefits and risks of individual functional foods and their physiologically active components. Health claims on food products, including functional foods, should be based on the significant scientific agreement standard of evidence and ADA supports label claims based on such strong scientific substantiation. Food and nutrition professionals will continue to work with the food industry, allied health professionals, the government, the scientific community, and the media to ensure that the public has accurate information regarding functional foods and thus should continue to educate themselves on this emerging area of food and nutrition science. Knowledge of the role of physiologically active food components, from plant, animal, and microbial food sources, has changed the role of diet in health. Functional foods have evolved as food and nutrition science has advanced beyond the treatment of deficiency syndromes to reduction of disease risk and health promotion. This position paper reviews the definition of functional foods, their regulation, and the scientific evidence supporting this evolving area of food and nutrition. Foods can no longer be evaluated only in terms of macronutrient and micronutrient content alone. Analyzing the content of other physiologically active components and evaluating their role in health promotion will be necessary. The availability of health-promoting functional foods in the US diet has the potential to help ensure a healthier population. However, each functional food should be evaluated on the basis of scientific evidence to ensure appropriate integration into a varied diet.

Biofield Physiology: A Framework for an Emerging Discipline

PubMed Central

Levin, Michael; McCraty, Rollin; Bat, Namuun; Ives, John A.; Lutgendorf, Susan K.; Oschman, James L.

2015-01-01

Biofield physiology is proposed as an overarching descriptor for the electromagnetic, biophotonic, and other types of spatially-distributed fields that living systems generate and respond to as integral aspects of cellular, tissue, and whole organism self-regulation and organization. Medical physiology, cell biology, and biophysics provide the framework within which evidence for biofields, their proposed receptors, and functions is presented. As such, biofields can be viewed as affecting physiological regulatory systems in a manner that complements the more familiar molecular-based mechanisms. Examples of clinically relevant biofields are the electrical and magnetic fields generated by arrays of heart cells and neurons that are detected, respectively, as electrocardiograms (ECGs) or magnetocardiograms (MCGs) and electroencephalograms (EEGs) or magnetoencephalograms (MEGs). At a basic physiology level, electromagnetic activity of neural assemblies appears to modulate neuronal synchronization and circadian rhythmicity. Numerous nonneural electrical fields have been detected and analyzed, including those arising from patterns of resting membrane potentials that guide development and regeneration, and from slowly-varying transepithelial direct current fields that initiate cellular responses to tissue damage. Another biofield phenomenon is the coherent, ultraweak photon emissions (UPE), detected from cell cultures and from the body surface. A physiological role for biophotons is consistent with observations that fluctuations in UPE correlate with cerebral blood flow, cerebral energy metabolism, and EEG activity. Biofield receptors are reviewed in 3 categories: molecular-level receptors, charge flux sites, and endogenously generated electric or electromagnetic fields. In summary, sufficient evidence has accrued to consider biofield physiology as a viable scientific discipline. Directions for future research are proposed. PMID:26665040

Stress physiology in marine mammals: how well do they fit the terrestrial model?

PubMed

Atkinson, Shannon; Crocker, Daniel; Houser, Dorian; Mashburn, Kendall

2015-07-01

Stressors are commonly accepted as the causal factors, either internal or external, that evoke physiological responses to mediate the impact of the stressor. The majority of research on the physiological stress response, and costs incurred to an animal, has focused on terrestrial species. This review presents current knowledge on the physiology of the stress response in a lesser studied group of mammals, the marine mammals. Marine mammals are an artificial or pseudo grouping from a taxonomical perspective, as this group represents several distinct and diverse orders of mammals. However, they all are fully or semi-aquatic animals and have experienced selective pressures that have shaped their physiology in a manner that differs from terrestrial relatives. What these differences are and how they relate to the stress response is an efflorescent topic of study. The identification of the many facets of the stress response is critical to marine mammal management and conservation efforts. Anthropogenic stressors in marine ecosystems, including ocean noise, pollution, and fisheries interactions, are increasing and the dramatic responses of some marine mammals to these stressors have elevated concerns over the impact of human-related activities on a diverse group of animals that are difficult to monitor. This review covers the physiology of the stress response in marine mammals and places it in context of what is known from research on terrestrial mammals, particularly with respect to mediator activity that diverges from generalized terrestrial models. Challenges in conducting research on stress physiology in marine mammals are discussed and ways to overcome these challenges in the future are suggested.

Biofield Physiology: A Framework for an Emerging Discipline.

PubMed

Hammerschlag, Richard; Levin, Michael; McCraty, Rollin; Bat, Namuun; Ives, John A; Lutgendorf, Susan K; Oschman, James L

2015-11-01

Biofield physiology is proposed as an overarching descriptor for the electromagnetic, biophotonic, and other types of spatially-distributed fields that living systems generate and respond to as integral aspects of cellular, tissue, and whole organism self-regulation and organization. Medical physiology, cell biology, and biophysics provide the framework within which evidence for biofields, their proposed receptors, and functions is presented. As such, biofields can be viewed as affecting physiological regulatory systems in a manner that complements the more familiar molecular-based mechanisms. Examples of clinically relevant biofields are the electrical and magnetic fields generated by arrays of heart cells and neurons that are detected, respectively, as electrocardiograms (ECGs) or magnetocardiograms (MCGs) and electroencephalograms (EEGs) or magnetoencephalograms (MEGs). At a basic physiology level, electromagnetic activity of neural assemblies appears to modulate neuronal synchronization and circadian rhythmicity. Numerous nonneural electrical fields have been detected and analyzed, including those arising from patterns of resting membrane potentials that guide development and regeneration, and from slowly-varying transepithelial direct current fields that initiate cellular responses to tissue damage. Another biofield phenomenon is the coherent, ultraweak photon emissions (UPE), detected from cell cultures and from the body surface. A physiological role for biophotons is consistent with observations that fluctuations in UPE correlate with cerebral blood flow, cerebral energy metabolism, and EEG activity. Biofield receptors are reviewed in 3 categories: molecular-level receptors, charge flux sites, and endogenously generated electric or electromagnetic fields. In summary, sufficient evidence has accrued to consider biofield physiology as a viable scientific discipline. Directions for future research are proposed.

Advanced Biotelemetry Systems for Space Life Sciences: PH Telemetry

NASA Technical Reports Server (NTRS)

Hines, John W.; Somps, Chris; Ricks, Robert; Kim, Lynn; Connolly, John P. (Technical Monitor)

1995-01-01

The SENSORS 2000! (S2K!) program at NASA's Ames Research Center is currently developing a biotelemetry system for monitoring pH and temperature in unrestrained subjects. This activity is part of a broader scope effort to provide an Advanced Biotelemetry System (ABTS) for use in future space life sciences research. Many anticipated research endeavors will require biomedical and biochemical sensors and related instrumentation to make continuous inflight measurements in a variable-gravity environment. Since crew time is limited, automated data acquisition, data processing, data storage, and subject health monitoring are required. An automated biochemical and physiological data acquisition system based on non invasive or implantable biotelemetry technology will meet these requirements. The ABTS will ultimately acquire a variety of physiological measurands including temperature, biopotentials (e.g. ECG, EEG, EMG, EOG), blood pressure, flow and dimensions, as well as chemical and biological parameters including pH. Development activities are planned in evolutionary, leveraged steps. Near-term activities include 1) development of a dual channel pH/temperature telemetry system, and 2) development of a low bandwidth, 4-channel telemetry system, that measures temperature, heart rate, pressure, and pH. This abstract describes the pH/temperature telemeter.

Metal ions potentiate microglia responsiveness to endotoxin.

PubMed

Rachmawati, Dessy; Peferoen, Laura A N; Vogel, Daphne Y S; Alsalem, Inás W A; Amor, Sandra; Bontkes, Hetty J; von Blomberg, B Mary E; Scheper, Rik J; van Hoogstraten, Ingrid M W

2016-02-15

Oral metal exposure has been associated with diverse adverse reactions, including neurotoxicity. We showed previously that dentally applied metals activate dendritic cells (MoDC) via TLR4 (Ni, Co, Pd) and TLR3 (Au). It is still unknown whether the low levels of dental metals reaching the brain can trigger local innate cells or prime them to become more responsive. Here we tested whether dentally applied metals (Cr, Fe, Co, Ni, Cu, Zn, Au, Hg) activate primary human microglia in vitro and, as a model, monocytic THP-1-cells, in high non-toxic as well as near-physiological concentrations. In addition the effects of 'near-physiological' metal exposure on endotoxin (LPS) responsiveness of these cells were evaluated. IL-8 and IL-6 production after 24h was used as read out. In high, non-toxic concentrations all transition metals except Cr induced IL-8 and IL-6 production in microglia, with Ni and Co providing the strongest stimulation. When using near-physiological doses (up to 10× the normal plasma concentration), only Zn and Cu induced significant IL-8 production. Of note, the latter metals also markedly potentiated LPS responsiveness of microglia and THP-1 cells. In conclusion, transition metals activate microglia similar to MoDCs. In near-physiological concentrations Zn and Cu are the most effective mediators of innate immune activation. A clear synergism between innate responses to Zn/Cu and LPS was observed, shedding new light on the possible relation between oral metal exposure and neurotoxicity. Copyright © 2015. Published by Elsevier B.V.

Clinical Assessment Applications of Ambulatory Biosensors

ERIC Educational Resources Information Center

Haynes, Stephen N.; Yoshioka, Dawn T.

2007-01-01

Ambulatory biosensor assessment includes a diverse set of rapidly developing and increasingly technologically sophisticated strategies to acquire minimally disruptive measures of physiological and motor variables of persons in their natural environments. Numerous studies have measured cardiovascular variables, physical activity, and biochemicals…

EVA Physiology, Systems and Performance [EPSP] Project

NASA Technical Reports Server (NTRS)

Gernhardt, Michael L.

2010-01-01

This viewgraph presentation gives a general overview of the biomedical and technological challenges of Extravehicular Activity (EVA). The topics covered include: 1) Prebreathe Protocols; 2) Lunar Suit Testing and Development; and 3) Lunar Electric Rover and Exploration Operations Concepts.

A student-centered approach for developing active learning: the construction of physical models as a teaching tool in medical physiology.

PubMed

Rezende-Filho, Flávio Moura; da Fonseca, Lucas José Sá; Nunes-Souza, Valéria; Guedes, Glaucevane da Silva; Rabelo, Luiza Antas

2014-09-15

Teaching physiology, a complex and constantly evolving subject, is not a simple task. A considerable body of knowledge about cognitive processes and teaching and learning methods has accumulated over the years, helping teachers to determine the most efficient way to teach, and highlighting student's active participation as a means to improve learning outcomes. In this context, this paper describes and qualitatively analyzes an experience of a student-centered teaching-learning methodology based on the construction of physiological-physical models, focusing on their possible application in the practice of teaching physiology. After having Physiology classes and revising the literature, students, divided in small groups, built physiological-physical models predominantly using low-cost materials, for studying different topics in Physiology. Groups were followed by monitors and guided by teachers during the whole process, finally presenting the results in a Symposium on Integrative Physiology. Along the proposed activities, students were capable of efficiently creating physiological-physical models (118 in total) highly representative of different physiological processes. The implementation of the proposal indicated that students successfully achieved active learning and meaningful learning in Physiology while addressing multiple learning styles. The proposed method has proved to be an attractive, accessible and relatively simple approach to facilitate the physiology teaching-learning process, while facing difficulties imposed by recent requirements, especially those relating to the use of experimental animals and professional training guidelines. Finally, students' active participation in the production of knowledge may result in a holistic education, and possibly, better professional practices.

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.

The lateral neostriatum is necessary for compensatory ingestive behaviour after intravascular dehydration in female rats.

PubMed

Lelos, M J; Harrison, D J; Rosser, A E; Dunnett, S B

2013-12-01

Aberrant striatal function results in an array of physiological symptoms, including impaired consummatory and regulatory behaviours, which can lead to weight loss and dehydration. It was hypothesised, therefore, that cell loss in the neostriatum may contribute to altered fluid intake by regulating physiological signals related to dehydration status. To test this theory, rats with lesions of the lateral neostriatum and sham controls underwent a series of physiological challenges, including the experimental induction of intracellular and intravascular dehydration. No baseline differences in prandial or non-prandial drinking were observed, nor were differences in locomotor activity evident between groups. Furthermore, intracellular dehydration increased water intake in lesion rats in a manner comparable to sham rats. Interestingly, a specific impairment was evident in lesion rats after subcutaneous injection of poly-ethylene glycol was used to induce intravascular dehydration, such that lesion rats failed to adapt their water intake to this physiological change. The results suggest that the striatal lesions resulted in regulatory dysfunction by impairing motivational control over compensatory ingestive behaviour after intravascular hydration, while the physiological signals related to dehydration remain intact. Loss of these cells in neurodegenerative disorders, such Huntington's disease, may contribute to regulatory changes evident in the course of the disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

Injectable Chitosan/β-Glycerophosphate System for Sustained Release: Gelation Study, Structural Investigation, and Erosion Tests.

PubMed

Dalmoro, Annalisa; Abrami, Michela; Galzerano, Barbara; Bochicchio, Sabrina; Barba, Anna Angela; Grassi, Mario; Larobina, Domenico

2017-01-01

Hydrogels can constitute reliable delivery systems of drugs, including those based on nucleic acids (NABDs) such as small interfering ribonucleic acid (siRNA). Their nature, structure, and response to physiological or external stimuli strongly influence the delivery mechanisms of entrapped active molecules, and, in turn, their possible uses in pharmacological and biomedical applications. In this study, a thermo-gelling chitosan/β-glycero-phosphate system has been optimized in order to assess its use as injectable system able to: i) gelling at physiological pH and temperature, and ii) modulate the release of included active ingredients. To this aim, we first analyzed the effect of acetic acid concentration on the gelation temperature. We then found the "optimized composition", namely, the one in which the Tgel is equal to the physiological temperature. The resulting gel was tested, by low field nuclear magnetic resonance (LF-NMR), to evaluate its average mesh-size, which can affect release kinetics of loaded drug. Finally, films of gelled chitosan, loaded with a model drug, have been tested in vitro to monitor their characteristic times, i.e. diffusion and erosion time, when they are exposed to a medium mimicking a physiological environment (buffer solution at pH 7.4). Results display that the optimized system is deemed to be an ideal candidate as injectable gelling material for a sustained release. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Regulators of Slc4 bicarbonate transporter activity

PubMed Central

Thornell, Ian M.; Bevensee, Mark O.

2015-01-01

The Slc4 family of transporters is comprised of anion exchangers (AE1-4), Na+-coupled bicarbonate transporters (NCBTs) including electrogenic Na/bicarbonate cotransporters (NBCe1 and NBCe2), electroneutral Na/bicarbonate cotransporters (NBCn1 and NBCn2), and the electroneutral Na-driven Cl-bicarbonate exchanger (NDCBE), as well as a borate transporter (BTR1). These transporters regulate intracellular pH (pHi) and contribute to steady-state pHi, but are also involved in other physiological processes including CO2 carriage by red blood cells and solute secretion/reabsorption across epithelia. Acid-base transporters function as either acid extruders or acid loaders, with the Slc4 proteins moving HCO−3 either into or out of cells. According to results from both molecular and functional studies, multiple Slc4 proteins and/or associated splice variants with similar expected effects on pHi are often found in the same tissue or cell. Such apparent redundancy is likely to be physiologically important. In addition to regulating pHi, a HCO−3 transporter contributes to a cell's ability to fine tune the intracellular regulation of the cotransported/exchanged ion(s) (e.g., Na+ or Cl−). In addition, functionally similar transporters or splice variants with different regulatory profiles will optimize pH physiology and solute transport under various conditions or within subcellular domains. Such optimization will depend on activated signaling pathways and transporter expression profiles. In this review, we will summarize and discuss both well-known and more recently identified regulators of the Slc4 proteins. Some of these regulators include traditional second messengers, lipids, binding proteins, autoregulatory domains, and less conventional regulators. The material presented will provide insight into the diversity and physiological significance of multiple members within the Slc4 gene family. PMID:26124722

Regulators of Slc4 bicarbonate transporter activity.

PubMed

Thornell, Ian M; Bevensee, Mark O

2015-01-01

The Slc4 family of transporters is comprised of anion exchangers (AE1-4), Na(+)-coupled bicarbonate transporters (NCBTs) including electrogenic Na/bicarbonate cotransporters (NBCe1 and NBCe2), electroneutral Na/bicarbonate cotransporters (NBCn1 and NBCn2), and the electroneutral Na-driven Cl-bicarbonate exchanger (NDCBE), as well as a borate transporter (BTR1). These transporters regulate intracellular pH (pHi) and contribute to steady-state pHi, but are also involved in other physiological processes including CO2 carriage by red blood cells and solute secretion/reabsorption across epithelia. Acid-base transporters function as either acid extruders or acid loaders, with the Slc4 proteins moving HCO(-) 3 either into or out of cells. According to results from both molecular and functional studies, multiple Slc4 proteins and/or associated splice variants with similar expected effects on pHi are often found in the same tissue or cell. Such apparent redundancy is likely to be physiologically important. In addition to regulating pHi, a HCO(-) 3 transporter contributes to a cell's ability to fine tune the intracellular regulation of the cotransported/exchanged ion(s) (e.g., Na(+) or Cl(-)). In addition, functionally similar transporters or splice variants with different regulatory profiles will optimize pH physiology and solute transport under various conditions or within subcellular domains. Such optimization will depend on activated signaling pathways and transporter expression profiles. In this review, we will summarize and discuss both well-known and more recently identified regulators of the Slc4 proteins. Some of these regulators include traditional second messengers, lipids, binding proteins, autoregulatory domains, and less conventional regulators. The material presented will provide insight into the diversity and physiological significance of multiple members within the Slc4 gene family.

Highly Stable Graphene-Based Nanocomposite (GO-PEI-Ag) with Broad-Spectrum, Long-Term Antimicrobial Activity and Antibiofilm Effects.

PubMed

Zhao, Rongtao; Kong, Wen; Sun, Mingxuan; Yang, Yi; Liu, Wanying; Lv, Min; Song, Shiping; Wang, Lihua; Song, Hongbin; Hao, Rongzhang

2018-05-30

Various silver nanoparticle (AgNP)-decorated graphene oxide (GO) nanocomposites (GO-Ag) have received increasing attention owing to their antimicrobial activity and biocompatibility; however, their aggregation in physiological solutions and the generally complex synthesis methods warrant improvement. This study aimed to synthesize a polyethyleneimine (PEI)-modified and AgNP-decorated GO nanocomposite (GO-PEI-Ag) through a facile approach through microwave irradiation without any extra reductants and surfactants; its antimicrobial activity was investigated on Gram-negative/-positive bacteria (including drug-resistant bacteria) and fungi. Compared with GO-Ag, GO-PEI-Ag acquired excellent stability in physiological solutions and electropositivity, showing substantially higher antimicrobial efficacy. Moreover, GO-PEI-Ag exhibited particularly excellent long-term effects, presenting no obvious decline in antimicrobial activity after 1 week storage in physiological saline and repeated use for three times and the lasting inhibition of bacterial growth in nutrient-rich culture medium. In contrast, GO-Ag exhibited a >60% decline in antimicrobial activity after storage. Importantly, GO-PEI-Ag effectively eliminated adhered bacteria, thereby preventing biofilm formation. The primary antimicrobial mechanisms of GO-PEI-Ag were evidenced as physical damage to the pathogen structure, causing cytoplasmic leakage. Hence, stable GO-PEI-Ag with robust, long-term antimicrobial activity holds promise in combating public-health threats posed by drug-resistant bacteria and biofilms.

Precocene-I inhibits juvenile hormone biosynthesis, ovarian activation, aggression and alters sterility signal production in bumble bee (Bombus terrestris) workers

USDA-ARS?s Scientific Manuscript database

Juvenile hormone (JH) is an important regulator of development and physiology in insects. While in many insect species, including bumble bees, JH function as gonadotropin in adults, in some highly eusocial insects its role has shifted to regulate social behavior including division of labor, dominanc...

Predicting students' happiness from physiology, phone, mobility, and behavioral data.

PubMed

Jaques, Natasha; Taylor, Sara; Azaria, Asaph; Ghandeharioun, Asma; Sano, Akane; Picard, Rosalind

2015-09-01

In order to model students' happiness, we apply machine learning methods to data collected from undergrad students monitored over the course of one month each. The data collected include physiological signals, location, smartphone logs, and survey responses to behavioral questions. Each day, participants reported their wellbeing on measures including stress, health, and happiness. Because of the relationship between happiness and depression, modeling happiness may help us to detect individuals who are at risk of depression and guide interventions to help them. We are also interested in how behavioral factors (such as sleep and social activity) affect happiness positively and negatively. A variety of machine learning and feature selection techniques are compared, including Gaussian Mixture Models and ensemble classification. We achieve 70% classification accuracy of self-reported happiness on held-out test data.

The relevance of phylogeny to studies of global change.

PubMed

Edwards, Erika J; Still, Christopher J; Donoghue, Michael J

2007-05-01

Phylogenetic thinking has infiltrated many areas of biological research, but has had little impact on studies of global ecology or climate change. Here, we illustrate how phylogenetic information can be relevant to understanding vegetation-atmosphere dynamics at ecosystem or global scales by re-analyzing a data set of carbonic anhydrase (CA) activity in leaves that was used to estimate terrestrial gross primary productivity. The original calculations relied on what appeared to be low CA activity exclusively in C4 grasses, but our analyses indicate that such activity might instead characterize the PACCAD grass lineage, which includes many widespread C3 species. We outline how phylogenetics can guide better taxon sampling of key physiological traits, and discuss how the emerging field of phyloinformatics presents a promising new framework for scaling from organism physiology to global processes.

Antecedents and mediators of physical activity in endometrial cancer survivors: Increasing physical activity through Steps to Health

PubMed Central

Cox, Matthew; Carmack, Cindy; Hughes, Daniel; Baum, George; Brown, Jubilee; Jhingran, Anuja; Lu, Karen; Basen-Engquist, Karen

2015-01-01

OBJECTIVE Research shows that physical activity (PA) has a positive effect on cancer survivors including improving quality of life, improving physical fitness, and decreasing risk for cancer recurrence in some cancer types. Theory-based intervention approaches have identified self-efficacy as a potential mediator of PA interventions. This study examines the temporal relationships at four time points (T1–T4) between several social cognitive theory constructs and PA among a group of endometrial cancer survivors receiving a PA intervention. METHOD A sample of 98 sedentary women who were at least six months post treatment for endometrial cancer were given an intervention to increase their PA. The study tested whether modeling, physiological somatic sensations, and social support at previous time points predicted self-efficacy at later time points, which in turn predicted PA at later time points. RESULTS Results indicate that as physiological somatic sensations at T2 decrease, self-efficacy at T3 increases, which leads to an increase in PA at T4. This suggests that self-efficacy is a significant mediator between physiological somatic sensations and PA. Exploratory follow up models suggest model fit can be improved with the addition of contemporaneous effects between self-efficacy and PA at T3 and T4, changing the timing of the mediational relationships. CONCLUSIONS Physiological somatic sensations appear to be an important construct to target in order to increase PA in this population. While self-efficacy appeared to mediate the relationship between physiological somatic sensations and PA, the timing of this relationship is requires further study. PMID:25642840

Genetic Influences on the Neural and Physiological Bases of Acute Threat: A Research Domain Criteria (RDoC) Perspective

PubMed Central

Sumner, Jennifer A.; Powers, Abigail; Jovanovic, Tanja; Koenen, Karestan C.

2015-01-01

The NIMH Research Domain Criteria (RDoC) initiative aims to describe key dimensional constructs underlying mental function across multiple units of analysis—from genes to observable behaviors—in order to better understand psychopathology. The acute threat (“fear”) construct of the RDoC Negative Valence System has been studied extensively from a translational perspective, and is highly pertinent to numerous psychiatric conditions, including anxiety and trauma-related disorders. We examined genetic contributions to the construct of acute threat at two units of analysis within the RDoC framework: 1) neural circuits and 2) physiology. Specifically, we focused on genetic influences on activation patterns of frontolimbic neural circuitry and on startle, skin conductance, and heart rate responses. Research on the heritability of activation in threat-related frontolimbic neural circuitry is lacking, but physiological indicators of acute threat have been found to be moderately heritable (35-50%). Genetic studies of the neural circuitry and physiology of acute threat have almost exclusively relied on the candidate gene method and, as in the broader psychiatric genetics literature, most findings have failed to replicate. The most robust support has been demonstrated for associations between variation in the serotonin transporter (SLC6A4) and catechol-O-methyltransferase (COMT) genes with threat-related neural activation and physiological responses. However, unbiased genome-wide approaches using very large samples are needed for gene discovery, and these can be accomplished with collaborative consortium-based research efforts, such as those of the Psychiatric Genomics Consortium (PGC) and Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium. PMID:26377804

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.

What is the physiological time to recovery after concussion? A systematic review.

PubMed

Kamins, Joshua; Bigler, Erin; Covassin, Tracey; Henry, Luke; Kemp, Simon; Leddy, John J; Mayer, Andrew; McCrea, Michael; Prins, Mayumi; Schneider, Kathryn J; Valovich McLeod, Tamara C; Zemek, Roger; Giza, Christopher C

2017-06-01

The aim of this study is to consolidate studies of physiological measures following sport-related concussion (SRC) to determine if a time course of postinjury altered neurobiology can be outlined. This biological time course was considered with respect to clinically relevant outcomes such as vulnerability to repeat injury and safe timing of return to physical contact risk. Systematic review. PubMed, CINAHL, Cochrane Central, PsychINFO. Studies were included if they reported original research on physiological or neurobiological changes after SRC. Excluded were cases series <5 subjects, reviews, meta-analyses, editorials, animal research and research not pertaining to SRC. A total of 5834 articles were identified, of which 80 were included for full-text data extraction and review. Relatively few longitudinal studies exist that follow both physiological dysfunction and clinical measures to recovery. Modalities of measuring physiological change after SRC were categorised into the following: functional MRI, diffusion tensor imaging, magnetic resonance spectroscopy, cerebral blood flow, electrophysiology, heart rate, exercise, fluid biomarkers and transcranial magnetic stimulation. Due to differences in modalities, time course, study design and outcomes, it is not possible to define a single 'physiological time window' for SRC recovery. Multiple studies suggest physiological dysfunction may outlast current clinical measures of recovery, supporting a buffer zone of gradually increasing activity before full contact risk. Future studies need to use generalisable populations, longitudinal designs following to physiological and clinical recovery and careful correlation of neurobiological modalities with clinical measures. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Physical Activity and Obesity: Biomechanical and Physiological Key Concepts

PubMed Central

Nantel, Julie; Mathieu, Marie-Eve; Prince, François

2011-01-01

Overweight (OW) and obesity (OB) are often associated with low levels of physical activity. Physical activity is recommended to reduce excess body weight, prevent body weight regain, and decrease the subsequent risks of developing metabolic and orthopedic conditions. However, the impact of OW and OB on motor function and daily living activities must be taken into account. OW and OB are associated with musculoskeletal structure changes, decreased mobility, modification of the gait pattern, and changes in the absolute and relative energy expenditures for a given activity. While changes in the gait pattern have been reported at the ankle, knee, and hip, modifications at the knee level might be the most challenging for articular integrity. This review of the literature combines concepts and aims to provide insights into the prescription of physical activity for this population. Topics covered include the repercussions of OW and OB on biomechanical and physiological responses associated with the musculoskeletal system and daily physical activity. Special attention is given to the effect of OW and OB in youth during postural (standing) and various locomotor (walking, running, and cycling) activities. PMID:21113311

Recognition of American Physiological Society members whose research publications had a significant impact on the discipline of physiology.

PubMed

Tipton, Charles M

2013-03-01

Society members whose research publication during the past 125 yr had an important impact on the discipline of physiology were featured at the American Physiological Society (APS)'s 125th Anniversary symposium. The daunting and challenging task of identifying and selecting significant publications was assumed by the Steering Committee of the History of Physiology Interest Group, who requested recommendations and rationales from all Sections, select Interest Groups, and active senior APS members. The request resulted in recommendations and rationales from nine Sections, one Interest Group, and 28 senior members, identifying 38 publications and 43 members for recognition purposes. The publication recommendations included 5 individuals (Cournand, Erlanger, Gasser, Hubel, and Wiesel) whose research significantly contributed to their selection for the Nobel Prize in Medicine or Physiology, 4 individuals who received multiple recommendations [i.e., Cannon (3), Curran (2), Fenn (3), and Hamilton (2)], and 11 members who had been APS Presidents. Of the recommended articles, 33% were from the American Journal of Physiology, with the earliest being published in 1898 (Cannon) and the latest in 2007 (Sigmund). For the brief oral presentations, the History of Physiology Steering Committee selected the first choices of the Sections or Interest Group, whereas rationales and representation of the membership were used for the presentations by senior members.

Application of Acceleration Sensors in Physiological Experiments

NASA Astrophysics Data System (ADS)

Vavrinský, Erik; Moskal'vá, Daniela; Darříček, Martin; Donoval, Martin; Horínek, František; Popovič, Marían; Miklovič, Peter

2014-09-01

This paper illustrates a promising application of an accelerometer sensor in physiological research, we demonstrated use of accelerometers for monitoring the standard proband physical activity (PA) and also in special applications like respiration and mechanical heart activity, the so-called seismocardiography (SCG) monitoring, physiological activation monitoring and mechanomyography (MMG)

The psychophysiology of parenting: Individual differences in autonomic reactivity to positive and negative mood inductions and observed parental affect during dyadic interactions with children.

PubMed

Connell, Arin M; Dawson, Glen C; Danzo, Sarah; McKillop, Hannah N

2017-02-01

Parenting is a complex activity driven, in part, by parental emotional and physiological responses. However, work examining the physiological underpinnings of parenting behavior is still in its infancy, and very few studies have examined such processes beyond early childhood. The current study examines associations between Autonomic Nervous System (ANS) indices of parents' physiological reactivity to positive and negative mood states and observed parental affect during a series of discussion tasks with their adolescent child. Respiratory Sinus Arrhythmia (RSA) was measured as an index of parasympathetic nervous system (PNS) activation while viewing film clips designed to induce neutral, sad, and amused mood states. Parental positive affect, anger, and distress were observed during a series of parent-child discussion tasks, which included an ambiguous discussion regarding adolescent growth, a conflict discussion, and a fun-activity planning discussion. Results supported the association between aspects of parental physiological reactivity and observed affect during dyadic interactions. Further, RSA interacted with maternal depression to predict observed positive affect, anger, and distress, although differences across tasks and specific emotions were found regarding the nature of the interaction effects. Overall, results suggest that such neurobiological processes may be particularly important predictors of parental behavior, particularly in at-risk populations. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The relationship between swainsonine containing plants and endophytic fungi

USDA-ARS?s Scientific Manuscript database

Swainsonine, an indolizidine alkaloid with significant physiological activity, is an a-mannosidase and mannosidase II inhibitor that alters glycoprotein processing and causes lysosomal storage disease. Swainsonine is present in a number of plant families worldwide including the Convolvulaceae, Faba...

The Mexican Axolotl in Schools

ERIC Educational Resources Information Center

Thomas, R. M.

1976-01-01

Suggests and describes laboratory activities in which the Mexican axolotl (Ambystoma mexicanum Shaw) is used, including experiments in embryology and early development, growth and regeneration, neoteny and metamorphosis, genetics and coloration, anatomy and physiology, and behavior. Discusses care and maintenance of animals. (CS)

A Prairie Pharmacy: An Introduction to Herbalism.

ERIC Educational Resources Information Center

Moore, Susan A.

2003-01-01

Presents a laboratory activity to teach medical biology to undergraduate nonmajor business students. Uses herbalism as the theme concept to integrate subjects, such as anatomy, physiology, medical theory, and terminology. Includes topics, such as herb collection, medicine preparation, and herb storage. (SOE)

Lymphocyte Electrotaxis in vitro and in vivo

PubMed Central

Lin, Francis; Baldessari, Fabio; Gyenge, Christina Crenguta; Sato, Tohru; Chambers, Robert D.; Santiago, Juan G.; Butcher, Eugene C.

2008-01-01

Electric fields are generated in vivo in a variety of physiologic and pathologic settings, including penetrating injury to epithelial barriers. An applied electric field with strength within the physiologic range can induce directional cell migration (i.e. electrotaxis) of epithelial cells, endothelial cells, fibroblasts, and neutrophils suggesting a potential role in cell positioning during wound healing. In the present study, we investigated the ability of lymphocytes to respond to applied direct current (DC) electric fields. Using a modified transwell assay and a simple microfluidic device, we show that human peripheral blood lymphocytes migrate toward the cathode in physiologically relevant DC electric fields. Additionally, electrical stimulation activates intracellular kinase signaling pathways shared with chemotactic stimuli. Finally, video microscopic tracing of GFP-tagged immunocytes in the skin of mouse ears reveals that motile cutaneous T cells actively migrate toward the cathode of an applied DC electric field. Lymphocyte positioning within tissues can thus be manipulated by externally applied electric fields, and may be influenced by endogenous electrical potential gradients as well. PMID:18684937

Lymphocyte electrotaxis in vitro and in vivo.

PubMed

Lin, Francis; Baldessari, Fabio; Gyenge, Christina Crenguta; Sato, Tohru; Chambers, Robert D; Santiago, Juan G; Butcher, Eugene C

2008-08-15

Electric fields are generated in vivo in a variety of physiologic and pathologic settings, including penetrating injury to epithelial barriers. An applied electric field with strength within the physiologic range can induce directional cell migration (i.e., electrotaxis) of epithelial cells, endothelial cells, fibroblasts, and neutrophils suggesting a potential role in cell positioning during wound healing. In the present study, we investigated the ability of lymphocytes to respond to applied direct current (DC) electric fields. Using a modified Transwell assay and a simple microfluidic device, we show that human PBLs migrate toward the cathode in physiologically relevant DC electric fields. Additionally, electrical stimulation activates intracellular kinase signaling pathways shared with chemotactic stimuli. Finally, video microscopic tracing of GFP-tagged immunocytes in the skin of mouse ears reveals that motile cutaneous T cells actively migrate toward the cathode of an applied DC electric field. Lymphocyte positioning within tissues can thus be manipulated by externally applied electric fields, and may be influenced by endogenous electrical potential gradients as well.

Physiological and biochemical characterization of Trichoderma harzianum, a biological control agent against soilborne fungal plant pathogens.

PubMed Central

Grondona, I; Hermosa, R; Tejada, M; Gomis, M D; Mateos, P F; Bridge, P D; Monte, E; Garcia-Acha, I

1997-01-01

Monoconidial cultures of 15 isolates of Trichoderma harzianum were characterized on the basis of 82 morphological, physiological, and biochemical features and 99 isoenzyme bands from seven enzyme systems. The results were subjected to numerical analysis which revealed four distinct groups. Representative sequences of the internal transcribed spacer 1 (ITS 1)-ITS 2 region in the ribosomal DNA gene cluster were compared between groups confirming this distribution. The utility of the groupings generated from the morphological, physiological, and biochemical data was assessed by including an additional environmental isolate in the electrophoretic analysis. The in vitro antibiotic activity of the T. harzianum isolates was assayed against 10 isolates of five different soilborne fungal plant pathogens: Aphanomyces cochlioides, Rhizoctonia solani, Phoma betae, Acremonium cucurbitacearum, and Fusarium oxysporum f. sp. radicis lycopersici. Similarities between levels and specificities of biological activity and the numerical characterization groupings are both discussed in relation to antagonist-specific populations in known and potential biocontrol species. PMID:9251205

Altered LARK Expression Perturbs Development and Physiology of the Drosophila PDF Clock Neurons

PubMed Central

Huang, Yanmei; Howlett, Eric; Stern, Michael; Jackson, F. Rob

2009-01-01

The LARK RNA-binding protein (RBP) has well documented roles in the circadian systems of Drosophila and mammals. Recent studies have demonstrated that the Drosophila LARK RBP is associated with many mRNA targets, in vivo, including those that regulate either neurophysiology or development of the nervous system. In the present study, we have employed conditional expression techniques to distinguish developmental and physiological functions of LARK for a defined class of neurons: the Pigment Dispersing Factor (PDF)-containing LNv clock neurons. We found that increased LARK expression during development dramatically alters the small LNv class of neurons with no obvious effects on the large LNv cells. Conversely, conditional expression of LARK at the adult stage results in altered clock protein rhythms and circadian locomotor activity, even though neural morphology is normal in such animals. Electrophysiological analyses at the larval neuromuscular junction indicate a role for LARK in regulating neuronal excitability. Altogether, our results demonstrate that LARK activity is critical for neuronal development and physiology. PMID:19303442

How consumer physical activity monitors could transform human physiology research

PubMed Central

Hall Brown, Tyish S.; Collier, Scott R.; Sandberg, Kathryn

2017-01-01

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 O2, 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. PMID:28052867

Deliberate acquisition of competence in physiological breech birth: A grounded theory study.

PubMed

Walker, Shawn; Scamell, Mandie; Parker, Pam

2018-06-01

Research suggests that the skill and experience of the attendant significantly affect the outcomes of vaginal breech births, yet practitioner experience levels are minimal within many contemporary maternity care systems. Due to minimal experience and cultural resistance, few practitioners offer vaginal breech birth, and many practice guidelines and training programmes recommend delivery techniques requiring supine maternal position. Fewer practitioners have skills to support physiological breech birth, involving active maternal movement and choice of birthing position, including upright postures such as kneeling, standing, squatting, or on a birth stool. How professionals learn complex skills contrary to those taught in their local practice settings is unclear. How do professionals develop competence and expertise in physiological breech birth? Nine midwives and five obstetricians with experience facilitating upright physiological breech births participated in semi-structured interviews. Data were analysed iteratively using constructivist grounded theory methods to develop an empirical theory of physiological breech skill acquisition. Among the participants in this research, the deliberate acquisition of competence in physiological breech birth included stages of affinity with physiological birth, critical awareness, intention, identity and responsibility. Expert practitioners operating across local and national boundaries guided less experienced practitioners. The results depict a specialist learning model which could be formalised in sympathetic training programmes, and evaluated. It may also be relevant to developing competence in other specialist/expert roles and innovative practices. Deliberate development of local communities of practice may support professionals to acquire elusive breech skills in a sustainable way. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

Functional, structural and phylogenetic analysis of domains underlying the Al-sensitivity of the aluminium-activated malate/anion transporter, TaALMT1

USDA-ARS?s Scientific Manuscript database

TaALMT1 (Triticum aestivum Aluminum Activated Malate Transporter) is the founding member of a novel gene family of anion transporters (ALMTs) that mediate the efflux of organic acids. A small subgroup of root-localized ALMTs, including TaALMT1, is physiologically associated with in planta aluminum (...

Gc protein (vitamin D-binding protein): Gc genotyping and GcMAF precursor activity.

PubMed

Nagasawa, Hideko; Uto, Yoshihiro; Sasaki, Hideyuki; Okamura, Natsuko; Murakami, Aya; Kubo, Shinichi; Kirk, Kenneth L; Hori, Hitoshi

2005-01-01

The Gc protein (human group-specific component (Gc), a vitamin D-binding protein or Gc globulin), has important physiological functions that include involvement in vitamin D transport and storage, scavenging of extracellular G-actin, enhancement of the chemotactic activity of C5a for neutrophils in inflammation and macrophage activation (mediated by a GalNAc-modified Gc protein (GcMAF)). In this review, the structure and function of the Gc protein is focused on especially with regard to Gc genotyping and GcMAF precursor activity. A discussion of the research strategy "GcMAF as a target for drug discovery" is included, based on our own research.

Big-conductance Ca2+-activated K+ channels in physiological and pathophysiological urinary bladder smooth muscle cells

PubMed Central

Parajuli, Shankar P.; Zheng, Yun-Min; Levin, Robert; Wang, Yong-Xiao

2016-01-01

ABSTRACT Contraction and relaxation of urinary bladder smooth muscle cells (UBSMCs) represent the important physiological functions of the bladder. Contractile responses in UBSMCs are regulated by a number of ion channels including big-conductance Ca2+- activated K+ (BK) channels. Great progress has been made in studies of BK channels in UBSMCs. The intent of this review is to summarize recent exciting findings with respect to the functional interactions of BK channels with muscarinic receptors, ryanodine receptors (RyRs) and inositol triphosphate receptors (IP3Rs) as well as their functional importance under normal and pathophysiological conditions. BK channels are highly expressed in UBSMCs. Activation of muscarinic M3 receptors inhibits the BK channel activity, facilitates opening of voltage-dependent Ca2+ (CaV) channels, and thereby enhances excitability and contractility of UBSMCs. Signaling molecules and regulatory mechanisms involving RyRs and IP3Rs have a significant effect on functions of BK channels and thereby regulate cellular responses in UBSMCs under normal and pathophysiological conditions including overactive bladders. Moreover, BK channels may represent a novel target for the treatment of bladder dysfunctions. PMID:27101440

What is conservation physiology? Perspectives on an increasingly integrated and essential science†

PubMed Central

Cooke, Steven J.; Sack, Lawren; Franklin, Craig E.; Farrell, Anthony P.; Beardall, John; Wikelski, Martin; Chown, Steven L.

2013-01-01

Globally, ecosystems and their constituent flora and fauna face the localized and broad-scale influence of human activities. Conservation practitioners and environmental managers struggle to identify and mitigate threats, reverse species declines, restore degraded ecosystems, and manage natural resources sustainably. Scientific research and evidence are increasingly regarded as the foundation for new regulations, conservation actions, and management interventions. Conservation biologists and managers have traditionally focused on the characteristics (e.g. abundance, structure, trends) of populations, species, communities, and ecosystems, and simple indicators of the responses to environmental perturbations and other human activities. However, an understanding of the specific mechanisms underlying conservation problems is becoming increasingly important for decision-making, in part because physiological tools and knowledge are especially useful for developing cause-and-effect relationships, and for identifying the optimal range of habitats and stressor thresholds for different organisms. When physiological knowledge is incorporated into ecological models, it can improve predictions of organism responses to environmental change and provide tools to support management decisions. Without such knowledge, we may be left with simple associations. ‘Conservation physiology’ has been defined previously with a focus on vertebrates, but here we redefine the concept universally, for application to the diversity of taxa from microbes to plants, to animals, and to natural resources. We also consider ‘physiology’ in the broadest possible terms; i.e. how an organism functions, and any associated mechanisms, from development to bioenergetics, to environmental interactions, through to fitness. Moreover, we consider conservation physiology to include a wide range of applications beyond assisting imperiled populations, and include, for example, the eradication of invasive species, refinement of resource management strategies to minimize impacts, and evaluation of restoration plans. This concept of conservation physiology emphasizes the basis, importance, and ecological relevance of physiological diversity at a variety of scales. Real advances in conservation and resource management require integration and inter-disciplinarity. Conservation physiology and its suite of tools and concepts is a key part of the evidence base needed to address pressing environmental challenges. PMID:27293585

Cardiotrophin 1 stimulates beneficial myogenic and vascular remodeling of the heart.

PubMed

Abdul-Ghani, Mohammad; Suen, Colin; Jiang, Baohua; Deng, Yupu; Weldrick, Jonathan J; Putinski, Charis; Brunette, Steve; Fernando, Pasan; Lee, Tom T; Flynn, Peter; Leenen, Frans H H; Burgon, Patrick G; Stewart, Duncan J; Megeney, Lynn A

2017-10-01

The post-natal heart adapts to stress and overload through hypertrophic growth, a process that may be pathologic or beneficial (physiologic hypertrophy). Physiologic hypertrophy improves cardiac performance in both healthy and diseased individuals, yet the mechanisms that propagate this favorable adaptation remain poorly defined. We identify the cytokine cardiotrophin 1 (CT1) as a factor capable of recapitulating the key features of physiologic growth of the heart including transient and reversible hypertrophy of the myocardium, and stimulation of cardiomyocyte-derived angiogenic signals leading to increased vascularity. The capacity of CT1 to induce physiologic hypertrophy originates from a CK2-mediated restraining of caspase activation, preventing the transition to unrestrained pathologic growth. Exogenous CT1 protein delivery attenuated pathology and restored contractile function in a severe model of right heart failure, suggesting a novel treatment option for this intractable cardiac disease.

A Physiological Signal Transmission Model to be Used for Specific Diagnosis of Cochlear Impairments

NASA Astrophysics Data System (ADS)

Saremi, Amin; Stenfelt, Stefan

2011-11-01

Many of the sophisticated characteristics of human auditory system are attributed to cochlea. Also, most of patients with a hearing loss suffer from impairments that originate from cochlea (sensorineural). Despite this, today's clinical diagnosis methods do not probe the specific origins of such cochlear lesions. The aim of this research is to introduce a physiological signal transmission model to be clinically used as a tool for diagnosis of cochlear losses. This model enables simulation of different bio-mechano-electrical processes which occur in the auditory organ of Corti inside the cochlea. What makes this model different from many available computational models is its loyalty to physiology since the ultimate goal is to model each single physiological phenomenon. This includes passive BM vibration, outer hair cells' performances such as nonlinear mechanoelectrical transduction (MET), active amplifications by somatic motor, as well as vibration to neural conversion at the inner hair cells.

State of the interface between conservation and physiology: a bibliometric analysis.

PubMed

Lennox, Robert; Cooke, Steven J

2014-01-01

Contemporary conservation science benefits from the perspectives of a variety of different disciplines, including a recent synergy with physiology, an interface known as 'conservation physiology'. To evaluate the degree of interaction between conservation and animal/plant physiology, we conducted three bibliometric analyses. We first pursued the use of the term 'conservation physiology' since its first definition in 2006 to determine how frequently it has been used and in which publications. Secondly, we evaluated the occurrence of conservation terms in animal and plant physiology journals, physiological terms in conservation journals, and a combination of terms in ecology journals. Thirdly, we explored trends in a subset of conservation physiology articles published between 2006 and 2012. We identified a surge in the use of the term 'conservation physiology' in 2012, after only a slow increase in usage between 2006 and 2011. Conservation journals tend to have been significantly more active in publishing conservation physiology than animal physiology, plant physiology or ecology journals. However, we found evidence that ecology and animal physiology journals began to incorporate more conservation physiology after 2006, while conservation- and plant physiology-themed journals did not. Among 299 conservation physiology articles that we identified, vertebrate taxa have been over-represented in conservation physiology compared with their relative taxonomic abundance, invertebrate taxa have been under-represented, and plants have been represented in proportion to their relative taxonomic abundance; however, those findings are reasonably consistent with publication trends in conservation biology. Diffuse distribution of conservation physiology papers throughout the literature may have been a barrier to the growth of the subdiscipline when the interface was emerging. The introduction of the focused journal Conservation Physiology in 2013 may address that deficiency. Moreover, development of a unifying framework could help to aggregate knowledge and attract potential contributors by highlighting and facilitating access to and application of conservation physiology.

Towards a psycho-physiological model of thermal perception

NASA Astrophysics Data System (ADS)

Auliciems, A.

1981-06-01

Recommendations for indoor thermal requirements have been based upon verbalized responses on traditional assumptions that (1) minimal thermoregulatory activity may be equated to maximum subjective acceptability (2) sensations and levels of discomfort are synonymous and (3) perception of warmth is exclusively the function of thermal stimulus — physiological response. These concepts are reviewed in the light of recent researches which indicate the inadequacy of the existing physiological models and methods of research. In particular, recognition is made of higher levels of mental integration of information flows which, it is argued, must include parameters of past cultural and climatic experiences and expectations. The aim is to initiate a more holistic approach to research into human thermal environments, and, a clearer definition of concepts significant to practical application.

AMP-Activated Protein Kinase: An Ubiquitous Signaling Pathway With Key Roles in the Cardiovascular System.

PubMed

Salt, Ian P; Hardie, D Grahame

2017-05-26

The AMP-activated protein kinase (AMPK) is a key regulator of cellular and whole-body energy homeostasis, which acts to restore energy homoeostasis whenever cellular energy charge is depleted. Over the last 2 decades, it has become apparent that AMPK regulates several other cellular functions and has specific roles in cardiovascular tissues, acting to regulate cardiac metabolism and contractile function, as well as promoting anticontractile, anti-inflammatory, and antiatherogenic actions in blood vessels. In this review, we discuss the role of AMPK in the cardiovascular system, including the molecular basis of mutations in AMPK that alter cardiac physiology and the proposed mechanisms by which AMPK regulates vascular function under physiological and pathophysiological conditions. © 2017 American Heart Association, Inc.

Thermal Infrared Imaging-Based Computational Psychophysiology for Psychometrics

PubMed Central

Cardone, Daniela; Pinti, Paola; Merla, Arcangelo

2015-01-01

Thermal infrared imaging has been proposed as a potential system for the computational assessment of human autonomic nervous activity and psychophysiological states in a contactless and noninvasive way. Through bioheat modeling of facial thermal imagery, several vital signs can be extracted, including localized blood perfusion, cardiac pulse, breath rate, and sudomotor response, since all these parameters impact the cutaneous temperature. The obtained physiological information could then be used to draw inferences about a variety of psychophysiological or affective states, as proved by the increasing number of psychophysiological studies using thermal infrared imaging. This paper presents therefore a review of the principal achievements of thermal infrared imaging in computational physiology with regard to its capability of monitoring psychophysiological activity. PMID:26339284

Quantitative physiologically based modeling of subjective fatigue during sleep deprivation.

PubMed

Fulcher, B D; Phillips, A J K; Robinson, P A

2010-05-21

A quantitative physiologically based model of the sleep-wake switch is used to predict variations in subjective fatigue-related measures during total sleep deprivation. The model includes the mutual inhibition of the sleep-active neurons in the hypothalamic ventrolateral preoptic area (VLPO) and the wake-active monoaminergic brainstem populations (MA), as well as circadian and homeostatic drives. We simulate sleep deprivation by introducing a drive to the MA, which we call wake effort, to maintain the system in a wakeful state. Physiologically this drive is proposed to be afferent from the cortex or the orexin group of the lateral hypothalamus. It is hypothesized that the need to exert this effort to maintain wakefulness at high homeostatic sleep pressure correlates with subjective fatigue levels. The model's output indeed exhibits good agreement with existing clinical time series of subjective fatigue-related measures, supporting this hypothesis. Subjective fatigue, adrenaline, and body temperature variations during two 72h sleep deprivation protocols are reproduced by the model. By distinguishing a motivation-dependent orexinergic contribution to the wake-effort drive, the model can be extended to interpret variation in performance levels during sleep deprivation in a way that is qualitatively consistent with existing, clinically derived results. The example of sleep deprivation thus demonstrates the ability of physiologically based sleep modeling to predict psychological measures from the underlying physiological interactions that produce them. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Protein disulfide isomerase a multifunctional protein with multiple physiological roles

NASA Astrophysics Data System (ADS)

Ali Khan, Hyder; Mutus, Bulent

2014-08-01

Protein disulfide isomerase (PDI), is a member of the thioredoxin superfamily of redox proteins. PDI has three catalytic activities including, thiol-disulfide oxireductase, disulfide isomerase and redox-dependent chaperone. Originally, PDI was identified in the lumen of the endoplasmic reticulum and subsequently detected at additional locations, such as cell surfaces and the cytosol. This review will provide an overview of the recent advances in relating the structural features of PDI to its multiple catalytic roles as well as its physiological and pathophysiological functions related to redox regulation and protein folding.

Clastogenic and physiological response of chromosomes to nine pesticides in the Vicia faba in vivo root tip assay system.

PubMed

deKergommeaux, D J; Grant, W F; Sandhu, S S

1983-10-01

9 common pesticides were assayed for clastogenic and physiological activity using Vicia faba as a eukaryotic, whole-organism, test system. The compounds tested included the insecticides acephate, demeton, monocrotophos, parathion-methyl, and trichlorfon; the fungicides captan and folpet; and the herbicides bromacil and simazine. The chemicals have been grouped according to relative genotoxicity (strongly positive: demeton, parathion-methyl; positive: folpet, acephate, monocrotophos, captan; weakly positive: bromacil, trichlorfon, simazine). The results were compared with those reported from other assay systems.

Back to the future! Revisiting the physiological cost of negative work as a team-based activity for exercise physiology students.

PubMed

Kilgas, Matthew A; Elmer, Steven J

2017-03-01

We implemented a team-based activity in our exercise physiology teaching laboratory that was inspired from Abbott et al.'s classic 1952 Journal of Physiology paper titled "The physiological cost of negative work." Abbott et al. connected two bicycles via one chain. One person cycled forward (muscle shortening contractions, positive work) while the other resisted the reverse moving pedals (muscle lengthening contractions, negative work), and the cost of work was compared. This study was the first to link human whole body energetics with isolated muscle force-velocity characteristics. The laboratory activity for our students ( n = 35) was designed to reenact Abbott et al.'s experiment, integrate previously learned techniques, and illustrate differences in physiological responses to muscle shortening and lengthening contractions. Students (11-12 students/laboratory section) were split into two teams (positive work vs. negative work). One student from each team volunteered to cycle against the other for ~10 min. The remaining students in each team were tasked with measuring: 1 ) O 2 consumption, 2 ) heart rate, 3 ) blood lactate, and 4 ) perceived exertion. Students discovered that O 2 consumption during negative work was about one-half that of positive work and all other physiological parameters were also substantially lower. Muscle lengthening contractions were discussed and applied to rehabilitation and sport training. The majority of students (>90%) agreed or strongly agreed that they stayed engaged during the activity and it improved their understanding of exercise physiology. All students recommended the activity be performed again. This activity was engaging, emphasized teamwork, yielded clear results, was well received, and preserved the history of classic physiological experiments. Copyright © 2017 the American Physiological Society.

Molecular cross-talk of IL-6 in tumors and new progress in combined therapy.

PubMed

Song, Zuoqing; Ren, Dian; Xu, Xiaohong; Wang, Yuxin

2018-06-01

IL-6, a cytokine activated by type I interferons (IFNs), is encoded by the IL-6 gene, and secreted by T cells and macrophages. It serves many purposes in the human body and is significant to pathological and physiological activities, such as acute inflammatory responses, autoimmune diseases, and tumor formation. The wide range of IL-6 actions on tumors rely on more than one specific pathway. Advances in modern research have determined that to fulfill its complex physiological functions, IL-6 must be involved in cross-talk with a number of other molecular pathways. Therefore, it is important to clarify the comprehensive pathway network associated with IL-6 activity and to explore the mechanisms to inhibit its pathological activity in order to develop corresponding treatment plans. This study is a simple review of the pathological and physiological actions of IL-6 on the human body. It explains in detail the molecular pathways involved in cross-talk between IL-6 and tumors, summarizing and discussing the latest progress made in IL-6-related internal medicine treatments in recent years, including chemotherapies, targeted therapies, and immunotherapies. Our results provide new insight into the treatment of tumors. © 2018 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Single-neuron identification of chemical constituents, physiological changes, and metabolism using mass spectrometry.

PubMed

Zhu, Hongying; Zou, Guichang; Wang, Ning; Zhuang, Meihui; Xiong, Wei; Huang, Guangming

2017-03-07

The use of single-cell assays has emerged as a cutting-edge technique during the past decade. Although single-cell mass spectrometry (MS) has recently achieved remarkable results, deep biological insights have not yet been obtained, probably because of various technical issues, including the unavoidable use of matrices, the inability to maintain cell viability, low throughput because of sample pretreatment, and the lack of recordings of cell physiological activities from the same cell. In this study, we describe a patch clamp/MS-based platform that enables the sensitive, rapid, and in situ chemical profiling of single living neurons. This approach integrates modified patch clamp technique and modified MS measurements to directly collect and detect nanoliter-scale samples from the cytoplasm of single neurons in mice brain slices. Abundant possible cytoplasmic constituents were detected in a single neuron at a relatively fast rate, and over 50 metabolites were identified in this study. The advantages of direct, rapid, and in situ sampling and analysis enabled us to measure the biological activities of the cytoplasmic constituents in a single neuron, including comparing neuron types by cytoplasmic chemical constituents; observing changes in constituent concentrations as the physiological conditions, such as age, vary; and identifying the metabolic pathways of small molecules.

Single-neuron identification of chemical constituents, physiological changes, and metabolism using mass spectrometry

PubMed Central

Zhu, Hongying; Zou, Guichang; Wang, Ning; Zhuang, Meihui; Xiong, Wei; Huang, Guangming

2017-01-01

The use of single-cell assays has emerged as a cutting-edge technique during the past decade. Although single-cell mass spectrometry (MS) has recently achieved remarkable results, deep biological insights have not yet been obtained, probably because of various technical issues, including the unavoidable use of matrices, the inability to maintain cell viability, low throughput because of sample pretreatment, and the lack of recordings of cell physiological activities from the same cell. In this study, we describe a patch clamp/MS-based platform that enables the sensitive, rapid, and in situ chemical profiling of single living neurons. This approach integrates modified patch clamp technique and modified MS measurements to directly collect and detect nanoliter-scale samples from the cytoplasm of single neurons in mice brain slices. Abundant possible cytoplasmic constituents were detected in a single neuron at a relatively fast rate, and over 50 metabolites were identified in this study. The advantages of direct, rapid, and in situ sampling and analysis enabled us to measure the biological activities of the cytoplasmic constituents in a single neuron, including comparing neuron types by cytoplasmic chemical constituents; observing changes in constituent concentrations as the physiological conditions, such as age, vary; and identifying the metabolic pathways of small molecules. PMID:28223513

Basic Scientific Principles of Diving

ERIC Educational Resources Information Center

MacLean, Don

1976-01-01

Described are some of the physical and physiological scientific principles related to diving. The article is written as supplementary information for a teacher and includes suggested activities, a keyed test, and a bibliography. This article complements one on Sea Lab II in the same issue. (MA)

Physiological indicators of pathologic video game use in adolescence.

PubMed

Coyne, Sarah M; Dyer, W Justin; Densley, Rebecca; Money, Nathan M; Day, Randal D; Harper, James M

2015-03-01

Pathologic video game use (PVGU) has been associated with a host of negative psychological, physical, and social outcomes during adolescence; however, little research has examined physiological predictors of such use. The purpose of the study was to examine physiological predictors of the development of PVGU across adolescence. The article involves a 1-year longitudinal study across midadolescence. Participants were 374 adolescents and their parents from a large metropolitan area in the Northwest United States. PVGU was assessed via questionnaire, as were a number of control variables. A number of physiological indicators including respiratory sinus arrhythmia (RSA) and galvanic skin conductance (indices of parasympathetic and sympathetic nervous system activity, respectively) were measured during baseline, a cognitively stimulating task (Rubik's cube), and a family problem-solving task. Less RSA withdrawal to a cognitively simulating task was related to greater pathologic video game symptoms, but less RSA withdrawal to a family problem-solving task was associated with the presence of pathologic video game symptoms (p < .05). For girls only, galvanic skin conductance activation during the family problem solving was related to greater pathologic video game symptoms (p < .01). These findings suggest that adolescents who do not find cognitive tasks stimulating physiologically have a greater severity of PVGU. Additionally, adolescents who show physiological signs of stress in a family task were more likely to have PVGU symptoms and only girls have more severe PVGU levels. This study is the first to show that physiological indicators predict PVGU over time in adolescence and has important implications regarding the prevention and treatment of PVGU in adolescence. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Free fatty acids-sensing G protein-coupled receptors in drug targeting and therapeutics.

PubMed

Yonezawa, Tomo; Kurata, Riho; Yoshida, Kaori; Murayama, Masanori A; Cui, Xiaofeng; Hasegawa, Akihiko

2013-01-01

G protein-coupled receptor (GPCR) (also known as seven-transmembrane domain receptor) superfamily represents the largest protein family in the human genome. These receptors respond to various physiological ligands such as photons, odors, pheromones, hormones, ions, and small molecules including amines, amino acids to large peptides and steroids. Thus, GPCRs are involved in many diseases and the target of around half of all conventional drugs. The physiological roles of free fatty acids (FFAs), in particular, long-chain FFAs, are important for the development of many metabolic disease including obesity, diabetes, and atherosclerosis. In the past half decade, deorphanization of several GPCRs has revealed that GPR40, GPR41, GPR43, GPR84 and GPR120 sense concentration of extracellular FFAs with various carbon chain lengths. GPR40 and GPR120 are activated by medium- and long-chain FFAs. GPR84 is activated by medium- chain, but not long-chain, FFAs. GPR41 and GPR43 are activated by short-chain FFAs. GPR40 is highly expressed in pancreatic beta cells and plays a crucial role in FFAs-induced insulin secretion. GPR120 is mainly expressed in enteroendocrine cells and plays an important role for FFAs-induced glucagon-like peptide-1. GPR43 is abundant in leukocytes and adipose tissue, whilst GPR41 is highly expressed in adipose tissue, the pancreas and leukocytes. GPR84 is expressed in leukocytes and monocyte/macrophage. This review aims to shed light on the physiological roles and development of drugs targeting these receptors.

Effects of polyamines and calcium and sodium ions on smooth muscle cytoskeleton-associated phosphatidylinositol (4)-phosphate 5-kinase.

PubMed

Chen, H; Baron, C B; Griffiths, T; Greeley, P; Coburn, R F

1998-10-01

In many different cell types, including smooth muscle cells (Baron et al., 1989, Am. J. Physiol., 256: C375-383; Baron et al., J. Pharmacol. Exp. Ther. 266: 8-15), phosphatidylinositol (4)-phosphate 5-kinase plays a critical role in the regulation of membrane concentrations of phosphatidylinositol (4,5)-bisphosphate and formation of inositol (1,4,5)-trisphosphate. In unstimulated porcine trachealis smooth muscle, 70% of total cellular phosphatidylinositol (4)-phosphate 5-kinase activity was associated with cytoskeletal proteins and only trace activity was detectable in isolated sarcolemma. Using two different preparations, we studied cytoskeleton-associated phosphatidyl inositol (4)-phosphate 5-kinase under conditions that attempted to mimic the ionic and thermal cytoplasmic environment of living cells. The cytoskeleton-associated enzyme, studied using phosphatidylinositol (4)-phosphate substrate concentrations that produced phosphatidylinositol 4,5-bisphosphate at about 10% of the maximal rate, was sensitive to free [Mg2+], had an absolute requirement for phosphatidylserine, phosphatidic acid, or phosphatidylinositol, and included type I isoforms. At 0.5 mM free [Mg2+], physiological spermine concentrations, 0.2-0.4 mM, increased phosphatidylinositol (4)-phosphate 5-kinase activity two to four times compared to controls run without spermine. The EC50 for spermine-evoked increases in activity was 0.17 +/- 0.02 mM. Spermine-evoked enzyme activity was a function of both free [Mg2+] and substrate concentration. Cytoskeleton-associated phosphatidylinositol (4)-phosphate 5-kinase was inhibited by free [Ca2+] over a physiological range for cytoplasm--10(-8) to 10(-5) M, an effect independent of the presence of calmodulin. Na+ over the range 20 to 50 mM also inhibited this enzyme activated by 5 mM Mg2+ but had no effect on spermine-activated enzyme. Na+, Ca2+, and spermine appear to be physiological modulators of smooth muscle cytoskeleton-bound phosphatidylinositol (4)-phosphate 5-kinase.

Monitoring the wild black bear's reaction to human and environmental stressors

PubMed Central

2011-01-01

Background Bears are among the most physiologically remarkable mammals. They spend half their life in an active state and the other half in a state of dormancy without food or water, and without urinating, defecating, or physical activity, yet can rouse and defend themselves when disturbed. Although important data have been obtained in both captive and wild bears, long-term physiological monitoring of bears has not been possible until the recent advancement of implantable devices. Results Insertable cardiac monitors that were developed for use in human heart patients (Reveal® XT, Medtronic, Inc) were implanted in 15 hibernating bears. Data were recovered from 8, including 2 that were legally shot by hunters. Devices recorded low heart rates (pauses of over 14 seconds) and low respiration rates (1.5 breaths/min) during hibernation, dramatic respiratory sinus arrhythmias in the fall and winter months, and elevated heart rates in summer (up to 214 beats/min (bpm)) and during interactions with hunters (exceeding 250 bpm). The devices documented the first and last day of denning, a period of quiescence in two parturient females after birthing, and extraordinary variation in the amount of activity/day, ranging from 0 (winter) to 1084 minutes (summer). Data showed a transition toward greater nocturnal activity in the fall, preceding hibernation. The data-loggers also provided evidence of the physiological and behavioral responses of bears to our den visits to retrieve the data. Conclusions Annual variations in heart rate and activity have been documented for the first time in wild black bears. This technique has broad applications to wildlife management and physiological research, enabling the impact of environmental stressors from humans, changing seasons, climate change, social interactions and predation to be directly monitored over multiple years. PMID:21849079

Probiotics normalize the gut-brain-microbiota axis in immunodeficient mice.

PubMed

Smith, Carli J; Emge, Jacob R; Berzins, Katrina; Lung, Lydia; Khamishon, Rebecca; Shah, Paarth; Rodrigues, David M; Sousa, Andrew J; Reardon, Colin; Sherman, Philip M; Barrett, Kim E; Gareau, Mélanie G

2014-10-15

The gut-brain-microbiota axis is increasingly recognized as an important regulator of intestinal physiology. Exposure to psychological stress causes activation of the hypothalamic-pituitary-adrenal (HPA) axis and causes altered intestinal barrier function, intestinal dysbiosis, and behavioral changes. The primary aim of this study was to determine whether the effects of psychological stress on intestinal physiology and behavior, including anxiety and memory, are mediated by the adaptive immune system. Furthermore, we wanted to determine whether treatment with probiotics would normalize these effects. Here we demonstrate that B and T cell-deficient Rag1(-/-) mice displayed altered baseline behaviors, including memory and anxiety, accompanied by an overactive HPA axis, increased intestinal secretory state, dysbiosis, and decreased hippocampal c-Fos expression. Both local (intestinal physiology and microbiota) and central (behavioral and hippocampal c-Fos) changes were normalized by pretreatment with probiotics, indicating an overall benefit on health conferred by changes in the microbiota, independent of lymphocytes. Taken together, these findings indicate a role for adaptive immune cells in maintaining normal intestinal and brain health in mice and show that probiotics can overcome this immune-mediated deficit in the gut-brain-microbiota axis. Copyright © 2014 the American Physiological Society.

Prohibitin( PHB) roles in granulosa cell physiology.

PubMed

Chowdhury, Indrajit; Thomas, Kelwyn; Thompson, Winston E

2016-01-01

Ovarian granulosa cells (GC) play an important role in the growth and development of the follicle in the process known as folliculogenesis. In the present review, we focus on recent developments in prohibitin (PHB) research in relation to GC physiological functions. PHB is a member of a highly conserved eukaryotic protein family containing the repressor of estrogen activity (REA)/stomatin/PHB/flotillin/HflK/C (SPFH) domain (also known as the PHB domain) found in diverse species from prokaryotes to eukaryotes. PHB is ubiquitously expressed in a circulating free form or is present in multiple cellular compartments including mitochondria, nucleus and plasma membrane. In mitochondria, PHB is anchored to the mitochondrial inner membrane and forms complexes with the ATPases associated with proteases having diverse cellular activities. PHB continuously shuttles between the mitochondria, cytosol and nucleus. In the nucleus, PHB interacts with various transcription factors and modulates transcriptional activity directly or through interactions with chromatin remodeling proteins. Many functions have been attributed to the mitochondrial and nuclear PHB complexes such as cellular differentiation, anti-proliferation, morphogenesis and maintenance of the functional integrity of the mitochondria. However, to date, the regulation of PHB expression patterns and GC physiological functions are not completely understood.

Prohibitin (PHB) roles in granulosa cell physiology

PubMed Central

Chowdhury, Indrajit; Thomas, Kelwyn; Thompson, Winston E.

2015-01-01

Ovarian granulosa cells (GC) play an important role in the growth and development of the follicle in the process known as folliculogenesis. In the present review, we focus on the recent developments in prohibitin (PHB) research in relation to GC physiological functions. PHB is a member of highly conserved eukaryotic protein family containing the repressor of estrogen activity (REA)/stomatin/prohibitin/flotillin/HflK/C (SPFH) domain [also known as the PHB domain] found in divergent species from prokaryotes to eukaryotes. PHB is ubiquitously expressed either in circulating free form or is present in multiple cellular compartments including mitochondria, nucleus and plasma membrane. In mitochondria, PHB is anchored to the mitochondrial inner membrane (IMM), and form complexes with the ATPases Associated with diverse cellular Activities (m-AAA) proteases. PHB continuously shuttles between the mitochondria, cytosol and nucleus. In the nucleus, PHB interacts with various transcription factors and modulate transcriptional activity directly or through interactions with chromatin remodeling proteins. Multiple functions have been attributed to the mitochondrial and nuclear prohibitin complexes such as cellular differentiation, anti-proliferation, morphogenesis and maintaining the functional integrity of the mitochondria. However, to date, the regulation of PHB expression patterns and GC physiological functions are not completely understood. PMID:26496733

A physiologically required G protein-coupled receptor (GPCR)-regulator of G protein signaling (RGS) interaction that compartmentalizes RGS activity.

PubMed

Croft, Wayne; Hill, Claire; McCann, Eilish; Bond, Michael; Esparza-Franco, Manuel; Bennett, Jeannette; Rand, David; Davey, John; Ladds, Graham

2013-09-20

G protein-coupled receptors (GPCRs) can interact with regulator of G protein signaling (RGS) proteins. However, the effects of such interactions on signal transduction and their physiological relevance have been largely undetermined. Ligand-bound GPCRs initiate by promoting exchange of GDP for GTP on the Gα subunit of heterotrimeric G proteins. Signaling is terminated by hydrolysis of GTP to GDP through intrinsic GTPase activity of the Gα subunit, a reaction catalyzed by RGS proteins. Using yeast as a tool to study GPCR signaling in isolation, we define an interaction between the cognate GPCR (Mam2) and RGS (Rgs1), mapping the interaction domains. This reaction tethers Rgs1 at the plasma membrane and is essential for physiological signaling response. In vivo quantitative data inform the development of a kinetic model of the GTPase cycle, which extends previous attempts by including GPCR-RGS interactions. In vivo and in silico data confirm that GPCR-RGS interactions can impose an additional layer of regulation through mediating RGS subcellular localization to compartmentalize RGS activity within a cell, thus highlighting their importance as potential targets to modulate GPCR signaling pathways.

Main results of the experiments conducted during the flight of the Kosmos-1129 Biosatellite and the status of preparation of studies on the next biosatllite

NASA Technical Reports Server (NTRS)

Ilin, E. A.

1980-01-01

Experiments included studies on the biological effects of weightlessness. Space flight stress, disorientation, and physiological factors are discussed for each experimental subject. The subjects included rats, drosophila flies, and plants. Metabolic rates were monitored along with other changes in the subject's activity cycles.

Preclinical experimental stress studies: protocols, assessment and comparison.

PubMed

Bali, Anjana; Jaggi, Amteshwar Singh

2015-01-05

Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Preclinical models are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these models are also important for the development of novel pharmacological agents for stress management. The well described preclinical stress models include immobilization, restraint, electric foot shock and social isolation stress. Stress assessment in animals is done at the behavioral level using open field, social interaction, hole board test; at the biochemical level by measuring plasma corticosterone and ACTH; at the physiological level by measuring food intake, body weight, adrenal gland weight and gastric ulceration. Furthermore the comparison between different stressors including electric foot shock, immobilization and cold stressor is described in terms of intensity, hormonal release, protein changes in brain, adaptation and sleep pattern. This present review describes these preclinical stress protocols, and stress assessment at different levels. Copyright © 2014 Elsevier B.V. All rights reserved.

Increased Interest in Physiology and Science among Adolescents after Presentations and Activities Administered by Undergraduate Physiology Students

ERIC Educational Resources Information Center

da Silva de Vargas, Liane; Rosa de Menezes, Jefferson; Billig Mello-Carpes, Pâmela

2016-01-01

In this article, the authors describe a set of activities performed in south Brazil that are aligned with the objectives of PhUn Week and promote the integration between universities and public schools and the dissemination of knowledge of physiology. To achieve this goal, the authors adopted a program in which undergraduate physiology students…

Martinomycin, a new polyether antibiotic produced by Streptomyces salvialis. I. Taxonomy, fermentation and biological activity.

PubMed

Bernan, V S; Montenegro, D A; Goodman, J J; Alluri, M R; Carter, G T; Abbanat, D R; Pearce, C J; Maiese, W M; Greenstein, M

1994-12-01

Actinomycete culture LL-D37187 has been found to produce the new polyether antibiotic martinomycin. Taxonomic studies, including morphological, physiological, and cell wall chemistry analyses, revealed that culture LL-D37187 is a novel streptomycete species, and the proposed name is Streptomyces salvialis. Martinomycin exhibits activity against the Southern Army Worm (Spodoptera eridania) and Gram-positive bacteria.

Screening of antagonistic bacteria isolated from Amorphophallus konjac rhizosphere soil

NASA Astrophysics Data System (ADS)

Lin, Tianxing; Gong, Mingfu; Guan, Qinlan; Huang, Ying; Qin, Fang

2018-04-01

Bacteria lived in Amorphaphallus konjac rhizosphere soil have the potential ability of antagonistic bacterial pathogen activity against to Erwinia carotovora subsp carotovora (Ecc). The paper was to study and analyze all strains of 18 bacteria isolated from A. konjac rhizosphere soil with strong antagonistic effect against to Ecc and to identify antagonistic bacteria with morphology, physiology and biochemistry characteristic. The antagonistic bacterial pathogen activity of different bacterial strains were significantly different. Five of 18 strains isolated from A. konjac rhizosphere soil, including AKSB03, AKSB05, AKSB08, AKSB13 and AKSB16 was screened with antagonistic wider more than 15 mm in first screening test. Strain AKSB08 and strain AKSB16 had a strong antagonism activity for Ecc with antagonistic wider more than 20 mm in second screening test. Strain AKSB08 and strain AKSB16 belonged to Bacillus with morphology, physiology and biochemistry characteristic.

Introductory overview of research instruments for recording the electrical activity of neurons in the human brain

NASA Astrophysics Data System (ADS)

Garell, P. C.; Granner, M. A.; Noh, M. D.; Howard, M. A.; Volkov, I. O.; Gillies, G. T.

1998-12-01

Scientific advancement is often spurred by the development of new instruments for investigation. Over the last several decades, many new instruments have been produced to further our understanding of the physiology of the human brain. We present a partial overview of some of these instruments, paying particular attention to those which record the electrical activity of the human brain. We preface the review with a brief primer on neuroanatomy and physiology, followed by a discussion of the latest types of apparatus used to investigate various properties of the central nervous system. A special focus is on microelectrode investigations that employ both intracellular and extracellular methods of recording the electrical activity of single neurons; another is on the modern electroencephalographic, electrocorticographic, and magnetoencephalographic methods used to study the spontaneous and evoked field potentials of the brain. Some examples of clinical applications are included, where appropriate.

One-Carbon Metabolism in Health and Disease

PubMed Central

Ducker, Gregory S.; Rabinowitz, Joshua D.

2017-01-01

One-carbon (1C) metabolism, mediated by the folate cofactor, supports multiple physiological processes. These include biosynthesis (purines and thymidine), amino acid homeostasis (glycine, serine, and methionine), epigenetic maintenance, and redox defense. Both within eukaryotic cells and across organs, 1C metabolic reactions are compartmentalized. Here we review the fundamentals of mammalian 1C metabolism, including the pathways active in different compartments, cell types, and biological states. Emphasis is given to recent discoveries enabled by modern genetics, analytical chemistry, and isotope tracing. An emerging theme is the biological importance of mitochondrial 1C reactions, both for producing 1C units that are exported to the cytosol and for making additional products, including glycine and NADPH. Increased clarity regarding differential folate pathway usage in cancer, stem cells, development, and adult physiology is reviewed and highlights new opportunities for selective therapeutic intervention. PMID:27641100

Predicting students’ happiness from physiology, phone, mobility, and behavioral data

PubMed Central

Jaques, Natasha; Taylor, Sara; Azaria, Asaph; Ghandeharioun, Asma; Sano, Akane; Picard, Rosalind

2017-01-01

In order to model students’ happiness, we apply machine learning methods to data collected from undergrad students monitored over the course of one month each. The data collected include physiological signals, location, smartphone logs, and survey responses to behavioral questions. Each day, participants reported their wellbeing on measures including stress, health, and happiness. Because of the relationship between happiness and depression, modeling happiness may help us to detect individuals who are at risk of depression and guide interventions to help them. We are also interested in how behavioral factors (such as sleep and social activity) affect happiness positively and negatively. A variety of machine learning and feature selection techniques are compared, including Gaussian Mixture Models and ensemble classification. We achieve 70% classification accuracy of self-reported happiness on held-out test data. PMID:28515966

Thomas Graham Brown (1882–1965): Behind the Scenes at the Cardiff Institute of Physiology

PubMed Central

Jones, J. Gareth; Tansey, E.M. (Tilli); Stuart, Douglas G.

2011-01-01

Thomas Graham Brown undertook seminal experiments on the neural control of locomotion between 1910 and 1915. Although elected to the Royal Society in 1927, his locomotion research was largely ignored until the 1960s when it was championed and extended by the distinguished neuroscientist, Anders Lundberg. Puzzlingly, Graham Brown's published research stopped in the 1920s and he became renowned as a mountaineer. In this article, we review his life and multifaceted career, including his active neurological service in WWI. We outline events behind the scenes during his tenure at Cardiff's Institute of Physiology in Wales, UK, including an interview with his technician, Terrence J. Surman, who worked in this institute for over half a century.

75 FR 74059 - Agency Information Collection Activities: Proposed Collection; Comment Request; Radioactive Drug...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-30

... Committees AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug... regulation, and include studies of metabolism, human physiology, pathophysiology, or biochemistry. Section... consent required under the regulations. Each female research subject of childbearing potential must state...

UNDERSTANDING THE EFFECTS OF ATRAZINE ON STEROIDOGENESIS IN THE HUMAN H295R AND RAT GRANULOSA CELLS

EPA Science Inventory

The effects of environmental chemicals on the catalytic activity of steroidogenic enzymes, including aromatase, have been well documented. However, specific effects of environmental chemicals on steroidogenesis and the physiological impact on local and systemic concentrations of ...

Basic Biology for Beginners.

ERIC Educational Resources Information Center

Gustafson, Pamela Anderson; Sorenson, Juanita S.

This publication provides the elementary teacher with sequential and developmental objectives in the areas of plants, animals, ecology, and physiology. At least one motivating "hands-on" activity is included for each objective. Age level (5-8, 8-10, 10-12), process emphasized (classification, experimenting, etc.), and group size…

Use of infrared telemetry as part of a nonintrusive inflight data collection system to collect human factors data

NASA Technical Reports Server (NTRS)

Micocci, Angelo

1993-01-01

The objective of this paper is to present a methodology and rationale for development of a Nonintrusive Inflight Data Collection System (NIDCS) to collect Human Factors (HF) data during a space mission. These data will enable the research team to identify and resolve issues. This paper will present the background and history of the NIDCS, the methodology and techniques employed versus those in current use on Earth, initial results of the effort--including a brief description of the equipment, and, finally, a discussion of the scientific importance and possible future applications of this system elsewhere. The schema for the NIDCS includes a collection of three types of data: behavioral, physiological, and biomechanical. These will be collected using videotape of crew members' activities, bioelectric signal measurement, and measurement of kinematics and kinetics, respectively. This paper will focus on the second type of data, physiological activity as determined by changes in bioelectric potentials as crew members perform daily assignments.

Drought coping strategies in cotton: increased crop per drop.

PubMed

Ullah, Abid; Sun, Heng; Yang, Xiyan; Zhang, Xianlong

2017-03-01

The growth and yield of many crops, including cotton, are affected by water deficit. Cotton has evolved drought specific as well as general morpho-physiological, biochemical and molecular responses to drought stress, which are discussed in this review. The key physiological responses against drought stress in cotton, including stomata closing, root development, cellular adaptations, photosynthesis, abscisic acid (ABA) and jasmonic acid (JA) production and reactive oxygen species (ROS) scavenging, have been identified by researchers. Drought stress induces the expression of stress-related transcription factors and genes, such as ROS scavenging, ABA or mitogen-activated protein kinases (MAPK) signalling genes, which activate various drought-related pathways to induce tolerance in the plant. It is crucial to elucidate and induce drought-tolerant traits via quantitative trait loci (QTL) analysis, transgenic approaches and exogenous application of substances. The current review article highlights the natural as well as engineered drought tolerance strategies in cotton. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Expression profiling of peroxisome proliferator-activated receptor-delta (PPAR-delta) in mouse tissues using tissue microarray.

PubMed

Higashiyama, Hiroyuki; Billin, Andrew N; Okamoto, Yuji; Kinoshita, Mine; Asano, Satoshi

2007-05-01

Peroxisome proliferator-activated receptor-delta (PPAR-delta) is known as a transcription factor involved in the regulation of fatty acid oxidation and mitochondrial biogenesis in several tissues, such as skeletal muscle, liver and adipose tissues. In this study, to elucidate systemic physiological functions of PPAR-delta, we examined the tissue distribution and localization of PPAR-delta in adult mouse tissues using tissue microarray (TMA)-based immunohistochemistry. PPAR-delta positive signals were observed on variety of tissues/cells in multiple systems including cardiovascular, urinary, respiratory, digestive, endocrine, nervous, hematopoietic, immune, musculoskeletal, sensory and reproductive organ systems. In these organs, PPAR-delta immunoreactivity was generally localized on the nucleus, although cytoplasmic localization was observed on several cell types including neurons in the nervous system and cells of the islet of Langerhans. These expression profiling data implicate various physiological roles of PPAR-delta in multiple organ systems. TMA-based immunohistochemistry enables to profile comprehensive protein localization and distribution in a high-throughput manner.

Wireless physiological monitoring and ocular tracking: 3D calibration in a fully-immersive virtual health care environment.

PubMed

Zhang, Lelin; Chi, Yu Mike; Edelstein, Eve; Schulze, Jurgen; Gramann, Klaus; Velasquez, Alvaro; Cauwenberghs, Gert; Macagno, Eduardo

2010-01-01

Wireless physiological/neurological monitoring in virtual reality (VR) offers a unique opportunity for unobtrusively quantifying human responses to precisely controlled and readily modulated VR representations of health care environments. Here we present such a wireless, light-weight head-mounted system for measuring electrooculogram (EOG) and electroencephalogram (EEG) activity in human subjects interacting with and navigating in the Calit2 StarCAVE, a five-sided immersive 3-D visualization VR environment. The system can be easily expanded to include other measurements, such as cardiac activity and galvanic skin responses. We demonstrate the capacity of the system to track focus of gaze in 3-D and report a novel calibration procedure for estimating eye movements from responses to the presentation of a set of dynamic visual cues in the StarCAVE. We discuss cyber and clinical applications that include a 3-D cursor for visual navigation in VR interactive environments, and the monitoring of neurological and ocular dysfunction in vision/attention disorders.

Physicians' psychophysiological stress reaction in medical communication of bad news: A critical literature review.

PubMed

Studer, Regina Katharina; Danuser, Brigitta; Gomez, Patrick

2017-10-01

Stress is a common phenomenon in medical professions. Breaking bad news (BBN) is reported to be a particularly distressing activity for physicians. Traditionally, the stress experienced by physicians when BBN was assessed exclusively using self-reporting. Only recently, the field of difficult physician-patient communication has used physiological assessments to better understand physicians' stress reactions. This paper's goals are to (a) review current knowledge about the physicians' psychophysiological stress reactions in BBN situations, (b) discuss methodological aspects of these studies and (c) suggest directions for future research. The seven studies identified all used scenarios with simulated patients but were heterogeneous with regard to other methodological aspects, such as the psychophysiological parameters, time points and durations assessed, comparative settings, and operationalisation of the communication scenarios. Despite this heterogeneity, all the papers reported increases in psychological and/or physiological activation when breaking bad news in comparison to control conditions, such as history taking or breaking good news. Taken together, the studies reviewed support the hypothesis that BBN is a psychophysiologically arousing and stressful task for medical professionals. However, much remains to be done. We suggest several future directions to advance the field. These include (a) expanding and refining the conceptual framework, (b) extending assessments to include more diverse physiological parameters, (c) exploring the modulatory effects of physicians' personal characteristics (e.g. level of experience), (d) comparing simulated and real-life physician-patient encounters and (e) combining physiological assessment with a discourse analysis of physician-patient communication. Copyright © 2017 Elsevier B.V. All rights reserved.

Nursing stress and patient care: real-time investigation of the effect of nursing tasks and demands on psychological stress, physiological stress, and job performance: study protocol.

PubMed

Farquharson, Barbara; Bell, Cheryl; Johnston, Derek; Jones, Martyn; Schofield, Pat; Allan, Julia; Ricketts, Ian; Morrison, Kenny; Johnston, Marie

2013-10-01

To examine the effects of nursing tasks (including their physiological and psychological demands, and the moderating effects of reward and control) on distress and job performance in real time. Nurses working in hospital settings report high levels of occupational stress. Stress in nurses has been linked to reduced physical and psychological health, reduced job satisfaction, increased sickness absence, increased staff turnover, and poorer job performance. In this study, we will investigate theoretical models of stress and use multiple methods, including real-time data collection, to assess the relationship between stress and different nursing tasks in general medical and surgical ward nurses. A real-time, repeated measures design. During 2011/2012, 100 nurses from a large general teaching hospital in Scotland will: (a) complete self-reports of mood; (b) have their heart rate and activity monitored over two shifts to obtain physiological indices of stress and energy expenditure; (c) provide perceptions of the determinants of stress in complex ward environments; and (d) describe their main activities. All measures will be taken repeatedly in real time over two working shifts. Data obtained in this study will be analysed to examine the relationships between nursing tasks, self-reported and physiological measures of stress and to assess the effect of occupational stress on multiple work outcomes. The results will inform theoretical understanding of nurse stress and its determinants and suggest possible targets for intervention to reduce stress and associated harmful consequences. © 2013 Blackwell Publishing Ltd.

The interaction of psychological and physiological homeostatic drives and role of general control principles in the regulation of physiological systems, exercise and the fatigue process - The Integrative Governor theory.

PubMed

St Clair Gibson, A; Swart, J; Tucker, R

2018-02-01

Either central (brain) or peripheral (body physiological system) control mechanisms, or a combination of these, have been championed in the last few decades in the field of Exercise Sciences as how physiological activity and fatigue processes are regulated. In this review, we suggest that the concept of 'central' or 'peripheral' mechanisms are both artificial constructs that have 'straight-jacketed' research in the field, and rather that competition between psychological and physiological homeostatic drives is central to the regulation of both, and that governing principles, rather than distinct physical processes, underpin all physical system and exercise regulation. As part of the Integrative Governor theory we develop in this review, we suggest that both psychological and physiological drives and requirements are underpinned by homeostatic principles, and that regulation of the relative activity of each is by dynamic negative feedback activity, as the fundamental general operational controller. Because of this competitive, dynamic interplay, we propose that the activity in all systems will oscillate, that these oscillations create information, and comparison of this oscillatory information with either prior information, current activity, or activity templates create efferent responses that change the activity in the different systems in a similarly dynamic manner. Changes in a particular system are always the result of perturbations occurring outside the system itself, the behavioural causative 'history' of this external activity will be evident in the pattern of the oscillations, and awareness of change occurs as a result of unexpected rather than planned change in physiological activity or psychological state.

Rapid direct methods for enumeration of specific, active bacteria in water and biofilms

NASA Technical Reports Server (NTRS)

McFeters, G. A.; Pyle, B. H.; Lisle, J. T.; Broadaway, S. C.

1999-01-01

Conventional methods for detecting indicator and pathogenic bacteria in water may underestimate the actual population due to sublethal environmental injury, inability of the target bacteria to take up nutrients and other physiological factors which reduce bacterial culturability. Rapid and direct methods are needed to more accurately detect and enumerate active bacteria. Such a methodological advance would provide greater sensitivity in assessing the microbiological safety of water and food. The principle goal of this presentation is to describe novel approaches we have formulated for the rapid and simultaneous detection of bacteria plus the determination of their physiological activity in water and other environmental samples. The present version of our method involves the concentration of organisms by membrane filtration or immunomagnetic separation and combines an intracellular fluorochrome (CTC) for assessment of respiratory activity plus fluorescent-labelled antibody detection of specific bacteria. This approach has also been successfully used to demonstrate spatial and temporal heterogeneities of physiological activities in biofilms when coupled with cryosectioning. Candidate physiological stains include those capable of determining respiratory activity, membrane potential, membrane integrity, growth rate and cellular enzymatic activities. Results obtained thus far indicate that immunomagnetic separation can provide a high degree of sensitivity in the recovery of seeded target bacteria (Escherichia coli O157:H7) in water and hamburger. The captured and stained target bacteria are then enumerated by either conventional fluorescence microscopy or ChemScan(R), a new instrument that is very sensitive and rapid. The ChemScan(R) laser scanning instrument (Chemunex, Paris, France) provides the detection of individual fluorescently labelled bacterial cells using three emission channels in less than 5 min. A high degree of correlation has been demonstrated between results obtained with the ChemScan and traditional plate counts of mixed natural bacterial populations in water. The continuing evolution of these methods will be valuable in the rapid and accurate analysis of environmental samples.

State of the interface between conservation and physiology: a bibliometric analysis

PubMed Central

Lennox, Robert; Cooke, Steven J.

2014-01-01

Contemporary conservation science benefits from the perspectives of a variety of different disciplines, including a recent synergy with physiology, an interface known as ‘conservation physiology’. To evaluate the degree of interaction between conservation and animal/plant physiology, we conducted three bibliometric analyses. We first pursued the use of the term ‘conservation physiology’ since its first definition in 2006 to determine how frequently it has been used and in which publications. Secondly, we evaluated the occurrence of conservation terms in animal and plant physiology journals, physiological terms in conservation journals, and a combination of terms in ecology journals. Thirdly, we explored trends in a subset of conservation physiology articles published between 2006 and 2012. We identified a surge in the use of the term ‘conservation physiology’ in 2012, after only a slow increase in usage between 2006 and 2011. Conservation journals tend to have been significantly more active in publishing conservation physiology than animal physiology, plant physiology or ecology journals. However, we found evidence that ecology and animal physiology journals began to incorporate more conservation physiology after 2006, while conservation- and plant physiology-themed journals did not. Among 299 conservation physiology articles that we identified, vertebrate taxa have been over-represented in conservation physiology compared with their relative taxonomic abundance, invertebrate taxa have been under-represented, and plants have been represented in proportion to their relative taxonomic abundance; however, those findings are reasonably consistent with publication trends in conservation biology. Diffuse distribution of conservation physiology papers throughout the literature may have been a barrier to the growth of the subdiscipline when the interface was emerging. The introduction of the focused journal Conservation Physiology in 2013 may address that deficiency. Moreover, development of a unifying framework could help to aggregate knowledge and attract potential contributors by highlighting and facilitating access to and application of conservation physiology. PMID:27293624

AMPK and the biochemistry of exercise: Implications for human health and disease

PubMed Central

Richter, Erik A.; Ruderman, Neil B.

2009-01-01

Synopsis AMP-activated protein kinase (AMPK) is a phylogenetically conserved fuel-sensing enzyme that is present in all mammalian cells. During exercise, it is activated in skeletal muscle in humans, and at least in rodents, also in adipose tissue, liver and perhaps other organs by events that increase the AMP/ATP ratio. When activated AMPK stimulates energy generating processes such as glucose uptake and fatty acid oxidation and decreases energy consuming processes such as protein and lipid synthesis. Exercise is perhaps the most powerful physiological activator of AMPK and a unique model for studying its many physiological roles. In addition, it improves the metabolic status of rodents with a metabolic syndrome phenotype, as does treatment with AMPK activating agents; therefore, it is tempting to attribute the therapeutic benefits of regular physical activity to activation of AMPK. Here we review the acute and chronic effects of exercise on AMPK activity in skeletal muscle and other tissues. We also discuss the potential role of AMPK activation in mediating the prevention and treatment by exercise of specific disorders associated with the metabolic syndrome including type 2 diabetes and Alzheimer’s disease. PMID:19196246

Human Intestinal Enteroids: a New Model To Study Human Rotavirus Infection, Host Restriction, and Pathophysiology

PubMed Central

Saxena, Kapil; Blutt, Sarah E.; Ettayebi, Khalil; Zeng, Xi-Lei; Broughman, James R.; Crawford, Sue E.; Karandikar, Umesh C.; Sastri, Narayan P.; Conner, Margaret E.; Opekun, Antone R.; Graham, David Y.; Qureshi, Waqar; Sherman, Vadim; Foulke-Abel, Jennifer; In, Julie; Kovbasnjuk, Olga; Zachos, Nicholas C.; Donowitz, Mark

2015-01-01

ABSTRACT Human gastrointestinal tract research is limited by the paucity of in vitro intestinal cell models that recapitulate the cellular diversity and complex functions of human physiology and disease pathology. Human intestinal enteroid (HIE) cultures contain multiple intestinal epithelial cell types that comprise the intestinal epithelium (enterocytes and goblet, enteroendocrine, and Paneth cells) and are physiologically active based on responses to agonists. We evaluated these nontransformed, three-dimensional HIE cultures as models for pathogenic infections in the small intestine by examining whether HIEs from different regions of the small intestine from different patients are susceptible to human rotavirus (HRV) infection. Little is known about HRVs, as they generally replicate poorly in transformed cell lines, and host range restriction prevents their replication in many animal models, whereas many animal rotaviruses (ARVs) exhibit a broader host range and replicate in mice. Using HRVs, including the Rotarix RV1 vaccine strain, and ARVs, we evaluated host susceptibility, virus production, and cellular responses of HIEs. HRVs infect at higher rates and grow to higher titers than do ARVs. HRVs infect differentiated enterocytes and enteroendocrine cells, and viroplasms and lipid droplets are induced. Heterogeneity in replication was seen in HIEs from different patients. HRV infection and RV enterotoxin treatment of HIEs caused physiological lumenal expansion detected by time-lapse microscopy, recapitulating one of the hallmarks of rotavirus-induced diarrhea. These results demonstrate that HIEs are a novel pathophysiological model that will allow the study of HRV biology, including host restriction, cell type restriction, and virus-induced fluid secretion. IMPORTANCE Our research establishes HIEs as nontransformed cell culture models to understand human intestinal physiology and pathophysiology and the epithelial response, including host restriction of gastrointestinal infections such as HRV infection. HRVs remain a major worldwide cause of diarrhea-associated morbidity and mortality in children ≤5 years of age. Current in vitro models of rotavirus infection rely primarily on the use of animal rotaviruses because HRV growth is limited in most transformed cell lines and animal models. We demonstrate that HIEs are novel, cellularly diverse, and physiologically relevant epithelial cell cultures that recapitulate in vivo properties of HRV infection. HIEs will allow the study of HRV biology, including human host-pathogen and live, attenuated vaccine interactions; host and cell type restriction; virus-induced fluid secretion; cell-cell communication within the epithelium; and the epithelial response to infection in cultures from genetically diverse individuals. Finally, drug therapies to prevent/treat diarrheal disease can be tested in these physiologically active cultures. PMID:26446608

NASA' s life sciences and space radiation biology.

PubMed

Rambaut, P; Nicogossian, A

1984-01-01

Plans for the various missions in which men and women are expected to participate during the next 10 years are outlined. Such missions include flights of up to three months duration in low earth orbit as well as possible short excursions to geosynchronous orbit. Research activities are described which cover the full spectrum of physiological and psychological responses to space flight. These activities are shown to contribute to the ongoing Shuttle program and the future Space Station. The paper includes a summary of the major technical thrusts needed to support extended habitation in space.

The physiological origin of task-evoked systemic artefacts in functional near infrared spectroscopy.

PubMed

Kirilina, Evgeniya; Jelzow, Alexander; Heine, Angela; Niessing, Michael; Wabnitz, Heidrun; Brühl, Rüdiger; Ittermann, Bernd; Jacobs, Arthur M; Tachtsidis, Ilias

2012-05-15

A major methodological challenge of functional near-infrared spectroscopy (fNIRS) is its high sensitivity to haemodynamic fluctuations in the scalp. Superficial fluctuations contribute on the one hand to the physiological noise of fNIRS, impairing the signal-to-noise ratio, and may on the other hand be erroneously attributed to cerebral changes, leading to false positives in fNIRS experiments. Here we explore the localisation, time course and physiological origin of task-evoked superficial signals in fNIRS and present a method to separate them from cortical signals. We used complementary fNIRS, fMRI, MR-angiography and peripheral physiological measurements (blood pressure, heart rate, skin conductance and skin blood flow) to study activation in the frontal lobe during a continuous performance task. The General Linear Model (GLM) was applied to analyse the fNIRS data, which included an additional predictor to account for systemic changes in the skin. We found that skin blood volume strongly depends on the cognitive state and that sources of task-evoked systemic signals in fNIRS are co-localized with veins draining the scalp. Task-evoked superficial artefacts were mainly observed in concentration changes of oxygenated haemoglobin and could be effectively separated from cerebral signals by GLM analysis. Based on temporal correlation of fNIRS and fMRI signals with peripheral physiological measurements we conclude that the physiological origin of the systemic artefact is a task-evoked sympathetic arterial vasoconstriction followed by a decrease in venous volume. Since changes in sympathetic outflow accompany almost any cognitive and emotional process, we expect scalp vessel artefacts to be present in a wide range of fNIRS settings used in neurocognitive research. Therefore a careful separation of fNIRS signals originating from activated brain and from scalp is a necessary precondition for unbiased fNIRS brain activation maps. Copyright © 2012 Elsevier Inc. All rights reserved.

Neo-Darwinism, the Modern Synthesis and selfish genes: are they of use in physiology?

PubMed Central

Noble, Denis

2011-01-01

This article argues that the gene-centric interpretations of evolution, and more particularly the selfish gene expression of those interpretations, form barriers to the integration of physiological science with evolutionary theory. A gene-centred approach analyses the relationships between genotypes and phenotypes in terms of differences (change the genotype and observe changes in phenotype). We now know that, most frequently, this does not correctly reveal the relationships because of extensive buffering by robust networks of interactions. By contrast, understanding biological function through physiological analysis requires an integrative approach in which the activity of the proteins and RNAs formed from each DNA template is analysed in networks of interactions. These networks also include components that are not specified by nuclear DNA. Inheritance is not through DNA sequences alone. The selfish gene idea is not useful in the physiological sciences, since selfishness cannot be defined as an intrinsic property of nucleotide sequences independently of gene frequency, i.e. the ‘success’ in the gene pool that is supposed to be attributable to the ‘selfish’ property. It is not a physiologically testable hypothesis. PMID:21135048

Neo-Darwinism, the modern synthesis and selfish genes: are they of use in physiology?

PubMed

Noble, Denis

2011-03-01

This article argues that the gene-centric interpretations of evolution, and more particularly the selfish gene expression of those interpretations, form barriers to the integration of physiological science with evolutionary theory. A gene-centred approach analyses the relationships between genotypes and phenotypes in terms of differences (change the genotype and observe changes in phenotype). We now know that, most frequently, this does not correctly reveal the relationships because of extensive buffering by robust networks of interactions. By contrast, understanding biological function through physiological analysis requires an integrative approach in which the activity of the proteins and RNAs formed from each DNA template is analysed in networks of interactions. These networks also include components that are not specified by nuclear DNA. Inheritance is not through DNA sequences alone. The selfish gene idea is not useful in the physiological sciences, since selfishness cannot be defined as an intrinsic property of nucleotide sequences independently of gene frequency, i.e. the 'success' in the gene pool that is supposed to be attributable to the 'selfish' property. It is not a physiologically testable hypothesis.

Carboxylated, Fe-filled multiwalled carbon nanotubes as versatile catalysts for O2 reduction and H2 evolution reactions at physiological pH.

PubMed

Bracamonte, M Victoria; Melchionna, Michele; Stopin, Antoine; Giulani, Angela; Tavagnacco, Claudio; Garcia, Yann; Fornasiero, Paolo; Bonifazi, Davide; Prato, Maurizio

2015-09-01

The development of new electrocatalysts for the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) at physiological pH is critical for several fields, including fuel cells and biological applications. Herein, the assembly of an electrode based on carboxyl-functionalised hydrophilic multiwalled carbon nanotubes (MWCNTs) filled with Fe phases and their excellent performance as electrocatalysts for ORR and HER at physiological pH are reported. The encapsulated Fe dramatically enhances the catalytic activity, and the graphitic shells play a double role of efficiently mediating the electron transfer to O2 and H2 O reactants and providing a cocoon that prevents uncontrolled Fe oxidation or leaching. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

AMP-Activated Protein Kinase – A Ubiquitous Signalling Pathway with Key Roles in the Cardiovascular System

PubMed Central

Salt, Ian P.; Hardie, D. Grahame

2017-01-01

The AMP-activated protein kinase (AMPK) is a key regulator of cellular and whole body energy homeostasis, which acts to restore energy homoeostasis whenever cellular energy charge is depleted. Over the last two decades, it has become apparent that AMPK regulates a number of other cellular functions and has specific roles in cardiovascular tissues, acting to regulate cardiac metabolism and contractile function as well as promoting anti-contractile, anti-inflammatory and anti-atherogenic actions in blood vessels. In this review, we will discuss the role of AMPK in the cardiovascular system, including the molecular basis of mutations in AMPK that alter cardiac physiology and the proposed mechanisms by which AMPK regulates vascular function under physiological and pathophysiological conditions. PMID:28546359

Applications of bioactive material from snakehead fish (Channa striata) for repairing of learning-memory capability and motoric activity: a case study of physiological aging and aging-caused oxidative stress in rats

NASA Astrophysics Data System (ADS)

Sunarno, Sunarno; Muflichatun Mardiati, Siti; Rahadian, Rully

2018-05-01

Physiological aging and aging due to oxidative stress are a major factor cause accelerated brain aging. Aging is characterized by a decrease of brain function of the hippocampus which is linked to the decline in the capability of learning-memory and motoric activity. The objective of this research is to obtain the important information about the mechanisms of brain antiaging associated with the improvement of hippocampus function, which includes aspects of learning-memory capability and motoric activity as well as mitochondrial ultrastructure profile of hippocampus cornu ammonis cells after treated by fish snakehead fish extract. Snakehead fish in Rawa Pening Semarang District allegedly holds the potential of endemic, which contains bioactive antiaging material that can prevent aging or improve the function of the hippocampus. This research has been conducted using a completely randomized design consisting of four treatments with five replications. The treatments were including rats with physiological aging or aging due to oxidative stress which was treated and without treated with meat extract of snakehead fish. The research was divided into two stages, i.e., determining of learning-memory capability, and determining motoric activity. The measured-parameters are time response to find feed, distance travel, time stereotypes, ambulatory time, and resting time. The result showed that the snakehead fish meat extract might improve function hippocampus, both in physiological aging or aging due to oxidative stress. The capability of learning and memory showed that the rats in both conditions of aging after getting treatment of meat extract of snakehead fish could get a feed in the fourth arm maze faster than rats untreated snakehead fish meat extract. Similarly, the measurement of the distance traveled, time stereotypes, ambulatory time, and resting time showed that rats which received treatment of meat extract of snakehead fish were better than the untreated rats. To conclude, the meat extract of snakehead fish can be used as antiaging material to improve the function of the hippocampus, to improve the capability of learning and memory, to improve motoric activity, and to prevent aging. These findings are expected to provide comprehensive information for the development of antiaging research as an effort to improve public health and to improve learning-memory capability and motoric activity.

PHYCAA+: an optimized, adaptive procedure for measuring and controlling physiological noise in BOLD fMRI.

PubMed

Churchill, Nathan W; Strother, Stephen C

2013-11-15

The presence of physiological noise in functional MRI can greatly limit the sensitivity and accuracy of BOLD signal measurements, and produce significant false positives. There are two main types of physiological confounds: (1) high-variance signal in non-neuronal tissues of the brain including vascular tracts, sinuses and ventricles, and (2) physiological noise components which extend into gray matter tissue. These physiological effects may also be partially coupled with stimuli (and thus the BOLD response). To address these issues, we have developed PHYCAA+, a significantly improved version of the PHYCAA algorithm (Churchill et al., 2011) that (1) down-weights the variance of voxels in probable non-neuronal tissue, and (2) identifies the multivariate physiological noise subspace in gray matter that is linked to non-neuronal tissue. This model estimates physiological noise directly from EPI data, without requiring external measures of heartbeat and respiration, or manual selection of physiological components. The PHYCAA+ model significantly improves the prediction accuracy and reproducibility of single-subject analyses, compared to PHYCAA and a number of commonly-used physiological correction algorithms. Individual subject denoising with PHYCAA+ is independently validated by showing that it consistently increased between-subject activation overlap, and minimized false-positive signal in non gray-matter loci. The results are demonstrated for both block and fast single-event task designs, applied to standard univariate and adaptive multivariate analysis models. Copyright © 2013 Elsevier Inc. All rights reserved.

Attenuation of smoke induced neuronal and physiological changes by bacoside rich extract in Wistar rats via down regulation of HO-1 and iNOS.

PubMed

Pandareesh, M D; Anand, T

2014-01-01

Bacopa monniera is well known herbal medicine for its neuropharmacological effects. It alleviates variety of disorders including neuronal and physiological changes. Crackers smoke is a potent risk factor that leads to free radical mediated oxidative stress in vivo. The aim of the current study is to evaluate the protective efficacy of B. monniera extract (BME) against crackers smoke induced neuronal and physiological changes via modulating inducible nitric oxide synthase (iNOS) and hemeoxygenase-1 (HO-1) expression in rats. Rats were exposed to smoke for 1h for a period of 3 weeks and consecutively treated with BME at three different dosages (i.e., 10, 20 and 40 mg/kg b.wt.). Our results elucidate that BME treatment ameliorates histopathalogical changes, reactive oxygen species levels, lipid peroxidation, acetylcholine esterase activity and brain neurotransmitter levels to normal. BME supplementation efficiently inhibited HO-1 expression and nitric oxide generation by down-regulating iNOS expression. Smoke induced depletion of antioxidant enzyme status, monoamine oxidase activity was also replenished by BME supplementation. Thus the present study indicates that BME ameliorates various impairments associated with neuronal and physiological changes in rats exposed to crackers smoke by its potent neuromodulatory, antioxidant and adaptogenic propensity. Copyright © 2013 Elsevier Inc. All rights reserved.

Doing peer review and receiving feedback: impact on scientific literacy and writing skills.

PubMed

Geithner, Christina A; Pollastro, Alexandria N

2016-03-01

Doing peer review has been effectively implemented to help students develop critical reading and writing skills; however, its application in Human Physiology programs is limited. The purpose of the present study was to determine the impact of peer review on Human Physiology majors' perceptions of their scientific literacy and writing skills. Students enrolled in the Scientific Writing course completed multiple writing assignments, including three revisions after receiving peer and instructor feedback. Students self-assessed their knowledge, skills, and attitudes related to science and writing in pre- and postcourse surveys (n = 26 with complete data). Seven survey items related to scientific literacy and writing skills impacted by peer review were selected for analysis. Scores on these survey items were summed to form a composite self-rating score. Responses to two questions regarding the most useful learning activities were submitted to frequency analysis. Mean postcourse scores for individual survey items and composite self-rating scores were significantly higher than precourse means (P < 0.05). Peer review was the most frequently noted among 21 learning activities for increasing scientific literacy and in the top 5 for improving writing skills. In conclusion, peer review is an effective teaching/learning approach for improving undergraduate Human Physiology majors' knowledge, skills, and attitudes regarding science and scientific writing. Copyright © 2016 The American Physiological Society.

The impact of transportation on physiological and behavioral parameters in Wistar rats: implications for acclimatization periods.

PubMed

Arts, Johanna W M; Kramer, Klaas; Arndt, Saskia S; Ohl, Frauke

2012-01-01

Transportation of laboratory rodents unavoidably causes stress. Nevertheless, very little is known about the effects of transportation and how long it takes for the animal to recuperate. In the present study, we investigated physiological and behavioral parameters before and after transportation in both transported and nontransported animals. We took blood samples to analyze plasma corticosterone and creatine kinase, and performed physiological measurements by means of telemetry, measuring heart rate, blood pressure, and activity. Behavior was measured by means of home cage observations. This study revealed that plasma corticosterone levels increased at least up to 16 days after transportation, blood pressure and heart rate showed a lasting decrease after transportation, grooming increased, and social interactions and locomotor activity decreased after transportation. With these data we demonstrate that there is a long-lasting effect of transportation on physiological and behavioral parameters. Our results show that the stressful impact of transportation embraces all parts of the procedure, including for example the packing of the animals. Researchers must be aware of this impact and provide a sufficient acclimatization period to allow for the (re-)stabilization of parameters. Insufficient acclimatization periods endanger not only the reliability of research results but also the welfare of the animal used.

Nutrition Action Pack.

ERIC Educational Resources Information Center

Sockut, Joanne; Stumpe, Stephanie

One of five McDonald's Action Packs, these instructional materials integrate elementary school-level nutrition education into other disciplines--biology, sociology, physiology, mathematics, and art. Contents include four units consisting of twelve activities. Unit 1, Why You Need Food, is a self-examination of what is needed for growth, health,…

Tenth workshop on seedling physiology and growth problems in oak plantings

Treesearch

Brian R. Lockhart; Emile S. Gardiner; Daniel C. (editors) Dey

2008-01-01

The University of Tennessee’s Tree Improvement Program is in its 49th year of conducting researchand technology transfer activities with a special emphasis on hardwood species, particularlyoak (Quercus spp.). Programs have included seed orchard construction and development, nurserystudies, silviculture...

Home-based vs. laboratory-based practical activities in the learning of human physiology: the perception of students.

PubMed

Neves, Ben-Hur S; Altermann, Caroline; Gonçalves, Rithiele; Lara, Marcus Vinícius; Mello-Carpes, Pâmela B

2017-03-01

Different tools have been used to facilitate the teaching and learning process in different areas of knowledge. Practical activities represent a form of teaching in which students not only listen to theoretical concepts but are also able to link theory and practice, and their importance in the biological sciences is notable. Sometimes, however, there is neither the time nor the resources to promote laboratory practices in physiology classes. In this sense, home-based practical activities may be an interesting alternative. Here, different approaches of practical activities were used and students' perceptions of the contributions of home-based practical activities (HBPA) and laboratory-based practical activities (LBPA) for physiology learning were collected. After each approach, the students evaluated the activities through an anonymous questionnaire. A total of 49 students completed the questionnaires, and the results demonstrate that both HBPA and LBPA were considered important contributors to physiology learning but that this contribution was more significant in the case of LBPA (χ 2 = 4.356, P = 0.037). Copyright © 2017 the American Physiological Society.

NASA Space Biology Program. Eighth annual symposium's program and abstracts

NASA Technical Reports Server (NTRS)

Halstead, T. W. (Editor)

1984-01-01

The activities included five half days of presentations by space biology principal investigators, an evening of poster session presentations by research associates, and an afternoon session devoted to the Flight Experiments Program. Areas of discussion included the following: gravity receptor mechanisms; physiological effects of gravity, structural mass; fluid dynamics and metabolism; mechanisms of plant response; and the role of gravity in development.

The Pathological and Physiological Roles of IL-6 Amplifier Activation

PubMed Central

Murakami, Masaaki; Hirano, Toshio

2012-01-01

The NFκB-triggered positive feedback loop for IL-6 signaling in type 1 collagen+ non-immune cells (IL-6 amplifier) was first discovered to be a synergistic signal that is activated following IL-17A and IL-6 stimulation in type 1 collagen+ non-immune cells. Subsequent disease models have shown that it can also be stimulated by the simultaneous activation of NFκB and STAT3, functions as a local chemokine inducer, and acts as a mechanism for local inflammation, particularly chronic ones like rheumatoid arthritis and a multiple sclerosis. Moreover, we have recently shown that hyper activation of the IL-6 amplifier via regional neural activation establishes a gateway for immune cells including autoreactive T cells to pass the blood-brain barrier at dorsal vessels in 5th lumbar cord. Here we review how the IL-6 amplifier is activated by neural activation and the physiological relevance of the gateway to the central nervous system. Accumulating evidences continues to suggest that the IL-6 amplifier offers a potential molecular mechanism for the relationship between neural activation and the development of inflammatory diseases, which could establish a new interdisciplinary field that fuses neurology and immunology. PMID:23136555

Ontogenetic Variation in the Thermal Biology of Yarrow's Spiny Lizard, Sceloporus jarrovii

PubMed Central

Gilbert, Anthony L.; Lattanzio, Matthew S.

2016-01-01

Climate change is rapidly altering the way current species interact with their environment to satisfy life-history demands. In areas anticipated to experience extreme warming, rising temperatures are expected to diminish population growth, due either to environmental degradation, or the inability to tolerate novel temperature regimes. Determining how at risk ectotherms, and lizards in particular, are to changes in climate traditionally emphasizes the thermal ecology and thermal sensitivity of physiology of adult members of a population. In this study, we reveal ontogenetic differences in thermal physiological and ecological traits that have been used to anticipate how ectotherms will respond to climate change. We show that the thermal biological traits of juvenile Yarrow’s Spiny Lizards (Sceloporus jarrovii) differ from the published estimates of the same traits for adult lizards. Juvenile S. jarrovii differ in their optimal performance temperature, field field-active body temperature, and critical thermal temperatures compared to adult S. jarrovii. Within juvenile S. jarrovii, males and females exhibit differences in field-active body temperature and desiccation tolerance. Given the observed age- and sex-related variation in thermal physiology, we argue that not including physiological differences in thermal biology throughout ontogeny may lead to misinterpretation of patterns of ecological or evolutionary change due to climate warming. Further characterizing the potential for ontogenetic changes in thermal biology would be useful for a more precise and accurate estimation of the role of thermal physiology in mediating population persistence in warmer environments. PMID:26840620

iTRAQ-based analysis of changes in the cassava root proteome reveals pathways associated with post-harvest physiological deterioration.

PubMed

Owiti, Judith; Grossmann, Jonas; Gehrig, Peter; Dessimoz, Christophe; Laloi, Christophe; Hansen, Maria Benn; Gruissem, Wilhelm; Vanderschuren, Hervé

2011-07-01

The short storage life of harvested cassava roots is an important constraint that limits the full potential of cassava as a commercial food crop in developing countries. We investigated the molecular changes during physiological deterioration of cassava root after harvesting using isobaric tags for relative and absolute quantification (iTRAQ) of proteins in soluble and non-soluble fractions prepared during a 96 h post-harvest time course. Combining bioinformatic approaches to reduce information redundancy for unsequenced or partially sequenced plant species, we established a comprehensive proteome map of the cassava root and identified quantitatively regulated proteins. Up-regulation of several key proteins confirmed that physiological deterioration of cassava root after harvesting is an active process, with 67 and 170 proteins, respectively, being up-regulated early and later after harvesting. This included regulated proteins that had not previously been associated with physiological deterioration after harvesting, such as linamarase, glutamic acid-rich protein, hydroxycinnamoyl transferase, glycine-rich RNA binding protein, β-1,3-glucanase, pectin methylesterase, maturase K, dehydroascorbate reductase, allene oxide cyclase, and proteins involved in signal pathways. To confirm the regulation of these proteins, activity assays were performed for selected enzymes. Together, our results show that physiological deterioration after harvesting is a highly regulated complex process involving proteins that are potential candidates for biotechnology approaches to reduce such deterioration. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

Immune physiology in tissue regeneration and aging, tumor growth, and regenerative medicine.

PubMed

Bukovsky, Antonin; Caudle, Michael R; Carson, Ray J; Gaytán, Francisco; Huleihel, Mahmoud; Kruse, Andrea; Schatten, Heide; Telleria, Carlos M

2009-02-13

The immune system plays an important role in immunity (immune surveillance), but also in the regulation of tissue homeostasis (immune physiology). Lessons from the female reproductive tract indicate that immune system related cells, such as intraepithelial T cells and monocyte-derived cells (MDC) in stratified epithelium, interact amongst themselves and degenerate whereas epithelial cells proliferate and differentiate. In adult ovaries, MDC and T cells are present during oocyte renewal from ovarian stem cells. Activated MDC are also associated with follicular development and atresia, and corpus luteum differentiation. Corpus luteum demise resembles rejection of a graft since it is attended by a massive influx of MDC and T cells resulting in parenchymal and vascular regression. Vascular pericytes play important roles in immune physiology, and their activities (including secretion of the Thy-1 differentiation protein) can be regulated by vascular autonomic innervation. In tumors, MDC regulate proliferation of neoplastic cells and angiogenesis. Tumor infiltrating T cells die among malignant cells. Alterations of immune physiology can result in pathology, such as autoimmune, metabolic, and degenerative diseases, but also in infertility and intrauterine growth retardation, fetal morbidity and mortality. Animal experiments indicate that modification of tissue differentiation (retardation or acceleration) during immune adaptation can cause malfunction (persistent immaturity or premature aging) of such tissue during adulthood. Thus successful stem cell therapy will depend on immune physiology in targeted tissues. From this point of view, regenerative medicine is more likely to be successful in acute rather than chronic tissue disorders.

Immune physiology in tissue regeneration and aging, tumor growth, and regenerative medicine

PubMed Central

Bukovsky, Antonin; Caudle, Michael R.; Carson, Ray J.; Gaytán, Francisco; Huleihel, Mahmoud; Kruse, Andrea; Schatten, Heide; Telleria, Carlos M.

2009-01-01

The immune system plays an important role in immunity (immune surveillance), but also in the regulation of tissue homeostasis (immune physiology). Lessons from the female reproductive tract indicate that immune system related cells, such as intraepithelial T cells and monocyte-derived cells (MDC) in stratified epithelium, interact amongst themselves and degenerate whereas epithelial cells proliferate and differentiate. In adult ovaries, MDC and T cells are present during oocyte renewal from ovarian stem cells. Activated MDC are also associated with follicular development and atresia, and corpus luteum differentiation. Corpus luteum demise resembles rejection of a graft since it is attended by a massive influx of MDC and T cells resulting in parenchymal and vascular regression. Vascular pericytes play important roles in immune physiology, and their activities (including secretion of the Thy-1 differentiation protein) can be regulated by vascular autonomic innervation. In tumors, MDC regulate proliferation of neoplastic cells and angiogenesis. Tumor infiltrating T cells die among malignant cells. Alterations of immune physiology can result in pathology, such as autoimmune, metabolic, and degenerative diseases, but also in infertility and intrauterine growth retardation, fetal morbidity and mortality. Animal experiments indicate that modification of tissue differentiation (retardation or acceleration) during immune adaptation can cause malfunction (persistent immaturity or premature aging) of such tissue during adulthood. Thus successful stem cell therapy will depend on immune physiology in targeted tissues. From this point of view, regenerative medicine is more likely to be successful in acute rather than chronic tissue disorders. PMID:20195382

When pain and hunger collide; psychological influences on differences in brain activity during physiological and non-physiological gastric distension.

PubMed

Coen, S J

2011-06-01

Functional neuroimaging has been used extensively in conjunction with gastric balloon distension in an attempt to unravel the relationship between the brain, regulation of hunger, satiety, and food intake tolerance. A number of researchers have also adopted a more physiological approach using intra-gastric administration of a liquid meal which has revealed different brain responses to gastric balloon distension. These differences are important as they question the utility and relevance of non-physiological models such as gastric balloon distension, especially when investigating mechanisms of feeding behavior such as satiety. However, an assessment of the relevance of physiological versus non-physiological gastric distension has been problematic due to differences in distension volumes between studies. In this issue of Neurogastroenterology and Motility, Geeraerts et al. compare brain activity during volume matched nutrient gastric distension and balloon distension in healthy volunteers. Gastric balloon distension activated the 'visceral pain neuromatrix'. This network of brain regions was deactivated during nutrient infusion, supporting the notion that brain activity during physiological versus non-physiological distension is indeed different. The authors suggest deactivation of the pain neuromatrix during nutrient infusion serves as a prerequisite for tolerance of normal meal volumes in health. © 2011 Blackwell Publishing Ltd.

CO2-O2 interactions in extension of tolerance to acute hypoxia

NASA Technical Reports Server (NTRS)

Lambertsen, C. J.

1995-01-01

Objectives and results of experimental projects a re summarized. The scope of information desired included (1) physiological and performance consequences of exposures to simulated microgravity, in rest and graded physical activity, (2) separate influences of graded degrees of atmospheric hypercapnia and hypoxia, and (3) composite effects of hypoxia and hypercapnia. The research objectives were selected for close relevance to existing quantitative information concerning interactions of hypercapnia and hypoxia on respiratory and brain circulatory control. They include: (1) to determine influences of normoxic immersion on interrelations of pulmonary ventilation, arterial PCO2 and PO2, and brain blood flow, in rest and physical work; (2) to determine influence of normoxic immersion on respiratory reactivity to atmospheric hypercapnia at rest; (3) to determine influence of atmospheric hypoxia on respiratory reactivity to hypercapnia at rest and in work; and (4) to provide physiological baselines of data concerning adaptations in acute exposures to aid in investigation of rates of adaptation or deteriorations in physiological or performance capability during subsequent multi-day exposures. A list of publications related to the present grant period is included along with an appendix describing the Performance Measurement System (human perceptual, cognitive and psychomotor functions).

Crew activities, science, and hazards of manned missions to Mars

NASA Technical Reports Server (NTRS)

Clark, Benton C.

1988-01-01

The crew scientific and nonscientific activities that will occur at each stage of a mission to Mars are examined. Crew activities during the interplanetary flight phase will include simulations, maintenance and monitoring, communications, upgrading procedures and operations, solar activity monitoring, cross-training and sharpening of skills, physical conditioning, and free-time activities. Scientific activities will address human physiology, human psychology, sociology, astronomy, space environment effects, manufacturing, and space agriculture. Crew activities on the Martian surface will include exploration, construction, manufacturing, food production, maintenance and training, and free time. Studies of Martian geology and atmosphere, of the life forms that may exist there, and of the Martian moons will occur on the planet's surface. Crew activities and scientific studies that will occur in Mars orbit, and the hazards relevant to each stage of the mission, are also addressed.

Brain angiotensin-(1-7)/Mas axis: A new target to reduce the cardiovascular risk to emotional stress.

PubMed

Fontes, Marco Antônio Peliky; Martins Lima, Augusto; Santos, Robson Augusto Souza dos

2016-04-01

Emotional stress is now considered a risk factor for several diseases including cardiac arrhythmias and hypertension. It is well known that the activation of neuroendocrine and autonomic mechanisms features the response to emotional stress. However, its link to cardiovascular diseases and the regulatory mechanisms involved remain to be further comprehended. The renin-angiotensin system (RAS) plays an important role in homeostasis on all body systems. Specifically in the brain, the RAS regulates a number of physiological aspects. Recent data indicate that the activation of angiotensin-converting enzyme/angiotensin II/AT1 receptor axis facilitates the emotional stress responses. On the other hand, growing evidence indicates that its counterregulatory axis, the angiotensin-converting enzyme 2 (ACE2)/(Ang)iotensin-(1-7)/Mas axis, reduces anxiety and attenuates the physiological responses to emotional stress. The present review focuses on angiotensin-(1-7)/Mas axis as a promising target to attenuate the physiological response to emotional stress reducing the risk of cardiovascular diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

The anticipatory regulation of performance: the physiological basis for pacing strategies and the development of a perception-based model for exercise performance.

PubMed

Tucker, R

2009-06-01

During self-paced exercise, the exercise work rate is regulated by the brain based on the integration of numerous signals from various physiological systems. It has been proposed that the brain regulates the degree of muscle activation and thus exercise intensity specifically to prevent harmful physiological disturbances. It is presently proposed how the rating of perceived exertion (RPE) is generated as a result of the numerous afferent signals during exercise and serves as a mediator of any subsequent alterations in skeletal muscle activation levels and exercise intensity. A conceptual model for how the RPE mediates feedforward, anticipatory regulation of exercise performance is proposed, and this model is applied to previously described research studies of exercise in various conditions, including heat, hypoxia and reduced energy substrate availability. Finally, the application of this model to recent novel studies that altered pacing strategies and performance is described utilising an RPE clamp design, central nervous system drugs and the provision of inaccurate duration or distance feedback to exercising athletes.

Physiological indicators of nitrogen response in short-rotation sycamore plantations. [Platanus occidentalis L

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

Tschaplinski, T.J.; Norby, R.J.

1989-04-01

American sycamore (Platanus occidentalis L.) seedlings were grown in the field under urea-nitrogen fertilization regimes to identify physiological variables that characterize the growth responses. Treatments included trees fertilized at the beginning of the growing season with 450 kg N/ha, trees fertilized periodically (three times during the growing season) at 37.5 kg N/ha, and unfertilized controls. Above ground biomass accumulation in the heaviest nitrogen treatment was three times that of the controls, and nearly as much growth occurred when less nitrogen was added periodically. Photosynthesis, chlorophyll concentrations, and growth increased rapidly after a midseason application of a small amount of nitrogen,more » but not to a late-season application. There was no evidence that fertilization extended the physiologically active season or increased susceptibility to drought or cold. Sycamore leaves accumulated sucrose and mannose in response to water and cold stress in all treatments. Photosynthetic pigment concentrations, net photosynthetic rate, and leaf nitrate reductase activity were sensitive indicators of nitrogen fertilization, but foliar concentrations of nitrate, total nitrogen, soluble carbohydrate and soluble protein were not.« less

Clinical experimental stress studies: methods and assessment.

PubMed

Bali, Anjana; Jaggi, Amteshwar Singh

2015-01-01

Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Stress induction methods are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these methods are also important for the development of novel pharmacological agents for stress management. The well-described methods to induce stress in humans include the cold pressor test, Trier Social Stress Test, Montreal Imaging Stress Task, Maastricht Acute Stress Test, CO2 challenge test, Stroop test, Paced Auditory Serial Addition Task, noise stress, and Mannheim Multicomponent Stress Test. Stress assessment in humans is done by measuring biochemical markers such as cortisol, cortisol awakening response, dexamethasone suppression test, salivary α-amylase, plasma/urinary norepinephrine, norepinephrine spillover rate, and interleukins. Physiological and behavioral changes such as galvanic skin response, heart rate variability, pupil size, and muscle and/or skin sympathetic nerve activity (microneurography) and cardiovascular parameters such as heart rate, blood pressure, and self-reported anxiety are also monitored to assess stress response. This present review describes these commonly employed methods to induce stress in humans along with stress assessment methods.

Stress, workload and physiology demand during extravehicular activity: a pilot study.

PubMed

Rai, Balwant; Kaur, Jasdeep; Foing, Bernard H

2012-06-01

Extravehicular activity (EVA), such as exercise performed under unique environmental conditions, is essential for supporting daily living in weightlessness and for further space exploration like long Mars mission. The study was planned stress, workload, and physiological demands of simulated Mars exploration. In this study, the six-person crew lived (24 hours) for 14 days during a short-term stay at the Mars Desert Research Station. The heart rates, salivary cortisol, workload, peak oxygen uptake or maximal aerobic capacity of the crew are measured before, during and after an EVA. Data for heart rate showed the same trend as peak oxygen uptake or maximal aerobic capacity, with a maximal increase to 85% of peak. The rating of subscale showed a significant increase in EVA as compared to run. Salivary cortisol levels and heart rates were increased in both groups, although significant increased of cortisol levels and heart rates more in EVA as compared to hill running crew members. Further study is required on large scale taken into account of limitations of this study and including other physiological and psychological parameters in Mars analog environment.

Bioconcentration of the antidepressant fluoxetine and its effects on the physiological and biochemical status in Daphnia magna.

PubMed

Ding, Jiannan; Zou, Hua; Liu, Qingqing; Zhang, Shanshan; Mamitiana Razanajatovo, Roger

2017-08-01

The aim of this study was to evaluate the bioconcentration potential of fluoxetine and its biological effects in Daphnia magna. After 48h of waterborne exposure, the bioconcentration of fluoxetine in D. magna was determined to be 460.61 and 174.41Lkg -1 for nominal exposure concentrations of 0.5 and 5µgL -1 , respectively. Moreover, various biological endpoints, including physiological responses (filtration and ingestion rates), enzymatic biomarkers related to neurotoxicity [acetylcholinesterase (AChE)] and antioxidant defense [superoxide dismutase (SOD)], and an oxidative stress damage marker [malondialdehyde (MDA)], were assessed. Fluoxetine exposure increased the filtration rate of daphnia, while the ingestion rate was not obviously modified. AChE activity was significantly inhibited, highlighting the neurotoxicity of fluoxetine on D. magna. However, with some alterations in the SOD activity and MDA content, no obvious oxidative damage was observed in D. magna exposed to fluoxetine at the tested concentrations. These results indicate that fluoxetine can be accumulated and consequently induce physiological and biochemical perturbations in D. magna. Copyright © 2017. Published by Elsevier Inc.

Active Learning Improves Student Performance in a Respiratory Physiology Lab

ERIC Educational Resources Information Center

Wolf, Alex M.; Liachovitzky, Carlos; Abdullahi, Abass S.

2015-01-01

This study assessed the effectiveness of the introduction of active learning exercises into the anatomy and physiology curriculum in a community college setting. Specifically, the incorporation of a spirometry-based respiratory physiology lab resulted in improved student performance in two concepts (respiratory volumes and the hallmarks of…

Community level physiological profiles (CLPP), characterization and microbial activity of soil amended with dairy sewage sludge.

PubMed

Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy

2012-01-01

The aim of the present work was to assess the influence of organic amendment applications compared to mineral fertilization on soil microbial activity and functional diversity. The field experiment was set up on a soil classified as an Eutric Cambisol developed from loess (South-East Poland). Two doses of both dairy sewage sludge (20 Mg·ha(-1) and 26 Mg·ha(-1)) and of mineral fertilizers containing the same amount of nutrients were applied. The same soil without any amendment was used as a control. The soil under undisturbed native vegetation was also included in the study as a representative background sample. The functional diversity (catabolic potential) was assessed using such indices as Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H). These indices were calculated, following the community level physiological profiling (CLPP) using Biolog Eco Plates. Soil dehydrogenase and respiratory activity were also evaluated. The indices were sensitive enough to reveal changes in community level physiological profiles due to treatment effects. It was shown that dairy sewage amended soil was characterized by greater AWCD, R, H and dehydrogenase and respiratory activity as compared to control or mineral fertilized soil. Analysis of variance (ANOVA) and principal component analysis (PCA) were used to depict the differences of the soil bacterial functional diversity between the treatments.

Community Level Physiological Profiles (CLPP), Characterization and Microbial Activity of Soil Amended with Dairy Sewage Sludge

PubMed Central

Frąc, Magdalena; Oszust, Karolina; Lipiec, Jerzy

2012-01-01

The aim of the present work was to assess the influence of organic amendment applications compared to mineral fertilization on soil microbial activity and functional diversity. The field experiment was set up on a soil classified as an Eutric Cambisol developed from loess (South-East Poland). Two doses of both dairy sewage sludge (20 Mg·ha−1 and 26 Mg·ha−1) and of mineral fertilizers containing the same amount of nutrients were applied. The same soil without any amendment was used as a control. The soil under undisturbed native vegetation was also included in the study as a representative background sample. The functional diversity (catabolic potential) was assessed using such indices as Average Well Color Development (AWCD), Richness (R) and Shannon–Weaver index (H). These indices were calculated, following the community level physiological profiling (CLPP) using Biolog Eco Plates. Soil dehydrogenase and respiratory activity were also evaluated. The indices were sensitive enough to reveal changes in community level physiological profiles due to treatment effects. It was shown that dairy sewage amended soil was characterized by greater AWCD, R, H and dehydrogenase and respiratory activity as compared to control or mineral fertilized soil. Analysis of variance (ANOVA) and principal component analysis (PCA) were used to depict the differences of the soil bacterial functional diversity between the treatments. PMID:22737006

Introductory Biology Labs... They Just Aren't Sexy Enough!

ERIC Educational Resources Information Center

Cotner, Sehoya; Gallup, Gordon G., Jr.

2011-01-01

The typical introductory biology curriculum includes the nature of science, evolution and genetics. Laboratory activities are designed to engage students in typical subject areas ranging from cell biology and physiology, to ecology and evolution. There are few, if any, laboratory classes exploring the biology and evolution of human sexual…

Advanced EVA system design requirements study, executive summary

NASA Technical Reports Server (NTRS)

1986-01-01

Design requirements and criteria for the space station advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related EVA support equipment were established. The EVA mission requirements, environments, and medical and physiological requirements, as well as operational, procedures and training issues were considered.

The tomato UV-damaged DNA binding protein 1 (DDB1) plays a role in organ size control via an epigenetic manner

USDA-ARS?s Scientific Manuscript database

Epigenetic regulation, including various covalent modifications of histone proteins and methylation of cytosine bases in DNA, participates broadly in many fundamentally physiological and developmental processes. The repressed or active states of transcription resulted from epigenetic modifications a...

High-fat diet exacerbates bone loss in mice implanted with low-dose slow-release lipopolysaccharide pellets

USDA-ARS?s Scientific Manuscript database

Obesity is associated with chronic up-regulation of inflammatory cytokines which stimulate osteoclast activity and bone resorption. Osteopenia or low bone mass is observed in a variety of physiological conditions with chronic inflammation including aging and post-menopause with estrogen deficiency. ...

Cardiac Rehabilitation. A Handbook for Vocational Rehabilitation Counselors.

ERIC Educational Resources Information Center

Brammell, H. L.; And Others

Basic information about heart disease and functional capacity assessment and its application to activity/job counseling are presented in this handbook for vocational rehabilitation counselors. Sections include the following: impact of heart disease; basic anatomy and physiology (e.g., the heart, pulmonary circulation, causes of cardiac pain, and…

Effect of water flow and chemical environment on microbiota growth and composition in the human colon.

PubMed

Cremer, Jonas; Arnoldini, Markus; Hwa, Terence

2017-06-20

The human gut harbors a dynamic microbial community whose composition bears great importance for the health of the host. Here, we investigate how colonic physiology impacts bacterial growth, which ultimately dictates microbiota composition. Combining measurements of bacterial physiology with analysis of published data on human physiology into a quantitative, comprehensive modeling framework, we show how water flow in the colon, in concert with other physiological factors, determine the abundances of the major bacterial phyla. Mechanistically, our model shows that local pH values in the lumen, which differentially affect the growth of different bacteria, drive changes in microbiota composition. It identifies key factors influencing the delicate regulation of colonic pH, including epithelial water absorption, nutrient inflow, and luminal buffering capacity, and generates testable predictions on their effects. Our findings show that a predictive and mechanistic understanding of microbial ecology in the gut is possible. Such predictive understanding is needed for the rational design of intervention strategies to actively control the microbiota.

Effect of water flow and chemical environment on microbiota growth and composition in the human colon

PubMed Central

Cremer, Jonas; Arnoldini, Markus; Hwa, Terence

2017-01-01

The human gut harbors a dynamic microbial community whose composition bears great importance for the health of the host. Here, we investigate how colonic physiology impacts bacterial growth, which ultimately dictates microbiota composition. Combining measurements of bacterial physiology with analysis of published data on human physiology into a quantitative, comprehensive modeling framework, we show how water flow in the colon, in concert with other physiological factors, determine the abundances of the major bacterial phyla. Mechanistically, our model shows that local pH values in the lumen, which differentially affect the growth of different bacteria, drive changes in microbiota composition. It identifies key factors influencing the delicate regulation of colonic pH, including epithelial water absorption, nutrient inflow, and luminal buffering capacity, and generates testable predictions on their effects. Our findings show that a predictive and mechanistic understanding of microbial ecology in the gut is possible. Such predictive understanding is needed for the rational design of intervention strategies to actively control the microbiota. PMID:28588144

Bioherbicides: Current knowledge on weed control mechanism.

PubMed

Radhakrishnan, Ramalingam; Alqarawi, Abdulaziz A; Abd Allah, Elsayed Fathi

2018-04-17

Weed control is a challenging event during crop cultivation. Integrated management, including the application of bioherbicides, is an emerging method for weed control in sustainable agriculture. Plant extracts, allelochemicals and some microbes are utilized as bioherbicides to control weed populations. Bioherbicides based on plants and microbes inhibit the germination and growth of weeds; however,few studies conducted in weed physiology. This review ascribes the current knowledge of the physiological changes in weeds that occur during the exposure to bioherbicides. Plant extracts or metabolites are absorbed by weed seeds, which initiates damage to the cell membrane, DNA, mitosis, amylase activity and other biochemical processes and delays or inhibits seed germination. The growth of weeds is also retarded due to low rates of root-cell division, nutrient uptake, photosynthetic pigment synthesis, and plant growth hormone synthesis, while the productions of reactive oxygen species (ROS) and stress-mediated hormones increase, including irregular antioxidant activity. However, lytic enzymes and toxic substances secreted from microbes degrade the weed seed coat and utilize the endosperm for survival, which inhibits seed germination. The microbes grow through the intercellular spaces to reach the root core, and the deposition of toxins in the cells affects cell division and cellular functions. Some of the metabolites of deleterious microbes cause disease, necrosis and chlorosis,which inhibit the germination and growth of weed seeds by suppressing photosynthesis and gibberellin activities and enhancing ROS, abscisic acid and ethylene. This review explains the effects of bioherbicides (derived from plants and microbes) on weed-plant physiology to elucidate their modes of action. Copyright © 2018 Elsevier Inc. All rights reserved.

Role of Regulators of G Protein Signaling Proteins in Bone Physiology and Pathophysiology

PubMed Central

Jules, Joel; Yang, Shuying; Chen, Wei; Li, Yi-Ping

2016-01-01

Regulators of G protein signaling (RGS) proteins enhance the intrinsic GTPase activity of α subunits of the heterotrimeric G protein complex of G protein-coupled receptors (GPCRs) and thereby inactivate signal transduction initiated by GPCRs. The RGS family consists of nearly 37 members with a conserved RGS homology domain which is critical for their GTPase accelerating activity. RGS proteins are expressed in most tissues, including heart, lung, brain, kidney, and bone and play essential roles in many physiological and pathological processes. In skeletal development and bone homeostasis as well as in many bone disorders, RGS proteins control the functions of various GPCRs, including the parathyroid hormone receptor type 1 and calcium-sensing receptor and also regulate various critical signaling pathways, such as Wnt and calcium oscillations. This chapter will discuss the current findings on the roles of RGS proteins in regulating signaling of key GPCRs in skeletal development and bone homeostasis. We also will examine the current updates of RGS proteins’ regulation of calcium oscillations in bone physiology and highlight the roles of RGS proteins in selected bone pathological disorders. Despite the recent advances in bone and mineral research, RGS proteins remain understudied in the skeletal system. Further understanding of the roles of RGS proteins in bone should not only provide great insights into the molecular basis of various bone diseases but also generate great therapeutic drug targets for many bone diseases. PMID:26123302

Differential and Conditional Activation of PKC-Isoforms Dictates Cardiac Adaptation during Physiological to Pathological Hypertrophy

PubMed Central

Naskar, Shaon; Datta, Kaberi; Mitra, Arkadeep; Pathak, Kanchan; Datta, Ritwik; Bansal, Trisha; Sarkar, Sagartirtha

2014-01-01

A cardiac hypertrophy is defined as an increase in heart mass which may either be beneficial (physiological hypertrophy) or detrimental (pathological hypertrophy). This study was undertaken to establish the role of different protein kinase-C (PKC) isoforms in the regulation of cardiac adaptation during two types of cardiac hypertrophy. Phosphorylation of specific PKC-isoforms and expression of their downstream proteins were studied during physiological and pathological hypertrophy in 24 week male Balb/c mice (Mus musculus) models, by reverse transcriptase-PCR, western blot analysis and M-mode echocardiography for cardiac function analysis. PKC-δ was significantly induced during pathological hypertrophy while PKC-α was exclusively activated during physiological hypertrophy in our study. PKC-δ activation during pathological hypertrophy resulted in cardiomyocyte apoptosis leading to compromised cardiac function and on the other hand, activation of PKC-α during physiological hypertrophy promoted cardiomyocyte growth but down regulated cellular apoptotic load resulting in improved cardiac function. Reversal in PKC-isoform with induced activation of PKC-δ and simultaneous inhibition of phospho-PKC-α resulted in an efficient myocardium to deteriorate considerably resulting in compromised cardiac function during physiological hypertrophy via augmentation of apoptotic and fibrotic load. This is the first report where PKC-α and -δ have been shown to play crucial role in cardiac adaptation during physiological and pathological hypertrophy respectively thereby rendering compromised cardiac function to an otherwise efficient heart by conditional reversal of their activation. PMID:25116170

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 a comprehensive overview of normal human respiratory physiology and the documented effects of slow breathing in healthy humans. To review and discuss the evidence and hypotheses regarding the mechanisms underlying slow breathing physiological effects in humans. To provide a definition of slow breathing and what may constitute “autonomically optimised respiration”. To open discussion on the potential clinical implications of slow breathing techniques and the need for further research. PMID:29209423

Physiological status of naturally reared juvenile spring chinook salmon in the Yakima River: Seasonal dynamics and changes associated with smolting

USGS Publications Warehouse

Beckman, B.R.; Larsen, D.A.; Sharpe, C.; Lee-Pawlak, B.; Schreck, C.B.; Dickhoff, Walton W.

2000-01-01

Two year-classes of juvenile spring chinook salmon Oncorhynchus tshawytscha from the Yakima River, Washington, were sampled from July (3-4 months postemergence) through May (yearling smolt out-migration). Physiological characters measured included liver glycogen, body lipid, gill Na+-K+ ATPase, plasma thyroxine (T4), and plasma insulin-like growth factor-I (IGF-I). Distinct physiological changes were found that corresponded to season. Summer and fall were characterized by relatively high body lipid and condition factor. Winter was characterized by decreases in body lipid, condition factor, and plasma hormones. An increase in condition factor and body lipid was found in February and March. Finally, April and May were characterized by dramatic changes characteristic of smolting, including increased gill Na+-K+ ATPase activity, plasma T4, and IGF-I and decreased condition factor, body lipid, and liver glycogen. These results create a physiological template for juvenile spring chinook salmon in the drainage that provides a baseline for comparison with other years, populations, and life history types. In addition, this baseline provides a standard for controlled laboratory experiments and a target for fish culturists who rear juvenile spring chinook salmon for release from conservation hatcheries. The implications of these results for juvenile chinook salmon ecology and life history are discussed.

An enzyme-linked immunosorbent assay-based system for determining the physiological level of poly(ADP-ribose) in cultured cells.

PubMed

Ida, Chieri; Yamashita, Sachiko; Tsukada, Masaki; Sato, Teruaki; Eguchi, Takayuki; Tanaka, Masakazu; Ogata, Shin; Fujii, Takahiro; Nishi, Yoshisuke; Ikegami, Susumu; Moss, Joel; Miwa, Masanao

2016-02-01

PolyADP-ribosylation is mediated by poly(ADP-ribose) (PAR) polymerases (PARPs) and may be involved in various cellular events, including chromosomal stability, DNA repair, transcription, cell death, and differentiation. The physiological level of PAR is difficult to determine in intact cells because of the rapid synthesis of PAR by PARPs and the breakdown of PAR by PAR-degrading enzymes, including poly(ADP-ribose) glycohydrolase (PARG) and ADP-ribosylhydrolase 3. Artifactual synthesis and/or degradation of PAR likely occurs during lysis of cells in culture. We developed a sensitive enzyme-linked immunosorbent assay (ELISA) to measure the physiological levels of PAR in cultured cells. We immediately inactivated enzymes that catalyze the synthesis and degradation of PAR. We validated that trichloroacetic acid is suitable for inactivating PARPs, PARG, and other enzymes involved in metabolizing PAR in cultured cells during cell lysis. The PAR level in cells harvested with the standard radioimmunoprecipitation assay buffer was increased by 450-fold compared with trichloroacetic acid for lysis, presumably because of activation of PARPs by DNA damage that occurred during cell lysis. This ELISA can be used to analyze the biological functions of polyADP-ribosylation under various physiological conditions in cultured cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Metabolic effects of physiological levels of caffeine in myotubes.

PubMed

Schnuck, Jamie K; Gould, Lacey M; Parry, Hailey A; Johnson, Michele A; Gannon, Nicholas P; Sunderland, Kyle L; Vaughan, Roger A

2018-02-01

Caffeine has been shown to stimulate multiple major regulators of cell energetics including AMP-activated protein kinase (AMPK) and Ca 2+ /calmodulin-dependent protein kinase II (CaMKII). Additionally, caffeine induces peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and mitochondrial biogenesis. While caffeine enhances oxidative metabolism, experimental concentrations often exceed physiologically attainable concentrations through diet. This work measured the effects of low-level caffeine on cellular metabolism and gene expression in myotubes, as well as the dependence of caffeine's effects on the nuclear receptor peroxisome proliferator-activated receptor beta/delta (PPARβ/δ). C2C12 myotubes were treated with various doses of caffeine for up to 24 h. Gene and protein expression were measured via qRT-PCR and Western blot, respectively. Cellular metabolism was determined via oxygen consumption and extracellular acidification rate. Caffeine significantly induced regulators of mitochondrial biogenesis and oxidative metabolism. Mitochondrial staining was suppressed in PPARβ/δ-inhibited cells which was rescued by concurrent caffeine treatment. Caffeine-treated cells also displayed elevated peak oxidative metabolism which was partially abolished following PPARβ/δ inhibition. Similar to past observations, glucose uptake and GLUT4 content were elevated in caffeine-treated cells, however, glycolytic metabolism was unaltered following caffeine treatment. Physiological levels of caffeine appear to enhance cell metabolism through mechanisms partially dependent on PPARβ/δ.

A review of the physiology of a survival expert of big freeze, deep snow, and an empty stomach: the boreal raccoon dog (Nyctereutes procyonoides).

PubMed

Mustonen, Anne-Mari; Nieminen, Petteri

2018-01-01

The raccoon dog (Nyctereutes procyonoides) is an invasive canid originating from eastern Asia. Here, we review its physiological adaptations to wintering, with an emphasis on northern Europe, where the raccoon dog spends the coldest part of the year in winter sleep. The timing of physiological changes related to wintering is connected to photoperiod by melatonin. In preparation to winter, raccoon dogs display autumnal hyperphagia and fattening probably regulated by the interaction of several peptide hormones. Sufficient fat deposition is essential for survival through the cold season and for reproduction in spring. The wintering strategy includes alternating periods of physical activity and passivity. Effective arousal and foraging during warmer bouts are enabled by normoglycaemia. During active periods, raccoon dogs are opportunistic participants in the food web, and they mainly utilize ungulate carcasses, plant material, and small mammals. Preferred wintertime habitats include watersides, forests, wetlands, and gardens. However, many food items become limited in mid-winter and snow restricts foraging leading to a negative energy balance. During passivity, energy is preserved by denning and by modest metabolic suppression, probably enabled by decreased thyroid hormone levels. Sleepiness and satiety could be maintained by high growth hormone and leptin concentrations. Several hormones participate in the extension of phase II of fasting with selective fatty acid mobilization and efficient protein conservation. The blood count, organ function tests, bone mass, and bone biomechanical properties exhibit high resistance against catabolism, and breeding can be successful after significant weight loss. The flexible physiological response to wintering is probably one reason enabling the successful colonization of this species into new areas.

Effects of rare earth elements and REE-binding proteins on physiological responses in plants.

PubMed

Liu, Dongwu; Wang, Xue; Chen, Zhiwei

2012-02-01

Rare earth elements (REEs), which include 17 elements in the periodic table, share chemical properties related to a similar external electronic configuration. REEs enriched fertilizers have been used in China since the 1980s. REEs could enter the cell and cell organelles, influence plant growth, and mainly be bound with the biological macromolecules. REE-binding proteins have been found in some plants. In addition, the chlorophyll activities and photosynthetic rate can be regulated by REEs. REEs could promote the protective function of cell membrane and enhance the plant resistance capability to stress produced by environmental factors, and affect the plant physiological mechanism by regulating the Ca²⁺ level in the plant cells. The focus of present review is to describe how REEs and REE-binding proteins participate in the physiological responses in plants.

Wearable Environmental and Physiological Sensing Unit

NASA Technical Reports Server (NTRS)

Spremo, Stevan; Ahlman, Jim; Stricker, Ed; Santos, Elmer

2007-01-01

The wearable environmental and physiological sensing unit (WEPS) is a prototype of systems to be worn by emergency workers (e.g., firefighters and members of hazardous-material response teams) to increase their level of safety. The WEPS includes sensors that measure a few key physiological and environmental parameters, a microcontroller unit that processes the digitized outputs of the sensors, and a radio transmitter that sends the processed sensor signals to a computer in a mobile command center for monitoring by a supervisor. The monitored parameters serve as real-time indications of the wearer s physical condition and level of activity, and of the degree and type of danger posed by the wearer s environment. The supervisor could use these indications to determine, for example, whether the wearer should withdraw in the face of an increasing hazard or whether the wearer should be rescued.

Physiologic adaptation of man in space; Proceedings of the Seventh International Man in Space Symposium, Houston, TX, Feb. 10-13, 1986

NASA Technical Reports Server (NTRS)

Holland, Albert W. (Editor)

1987-01-01

Topics discussed in this volume include space motion sickness, cardiovascular adaptation, fluid shifts, extravehicular activity, general physiology, perception, vestibular response modifications, vestibular physiology, and pharmacology. Papers are presented on the clinical characterization and etiology of space motion sickness, ultrasound techniques in space medicine, fluid shifts in weightlessness, Space Shuttle inflight and postflight fluid shifts measured by leg volume changes, and the probability of oxygen toxicity in an 8-psi space suit. Consideration is also given to the metabolic and hormonal status of crewmembers in short-term space flights, adaptive changes in perception of body orientation and mental image rotation in microgravity, the effects of a visual-vestibular stimulus on the vestibulo-ocular reflex, rotation tests in the weightless phase of parabolic flight, and the mechanisms of antimotion sickness drugs.

Molecular basis of physiological heart growth: fundamental concepts and new players

PubMed Central

Maillet, Marjorie; van Berlo, Jop H.; Molkentin, Jeffery D.

2015-01-01

The heart hypertrophies in response to developmental signals as well as increased workload. Although adult-onset hypertrophy can ultimately lead to disease, cardiac hypertrophy is not necessarily maladaptive and can even be beneficial. Progress has been made in our understanding of the structural and molecular characteristics of physiological cardiac hypertrophy, as well as of the endocrine effectors and associated signalling pathways that regulate it. Physiological hypertrophy is initiated by finite signals, which include growth hormones (such as thyroid hormone, insulin, insulin-like growth factor 1 and vascular endothelial growth factor) and mechanical forces that converge on a limited number of intracellular signalling pathways (such as PI3K, AKT, AMP-activated protein kinase and mTOR) to affect gene transcription, protein translation and metabolism. Harnessing adaptive signalling mediators to reinvigorate the diseased heart could have important medical ramifications. PMID:23258295

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.

Role of renal sensory nerves in physiological and pathophysiological conditions

PubMed Central

2014-01-01

Whether activation of afferent renal nerves contributes to the regulation of arterial pressure and sodium balance has been long overlooked. In normotensive rats, activating renal mechanosensory nerves decrease efferent renal sympathetic nerve activity (ERSNA) and increase urinary sodium excretion, an inhibitory renorenal reflex. There is an interaction between efferent and afferent renal nerves, whereby increases in ERSNA increase afferent renal nerve activity (ARNA), leading to decreases in ERSNA by activation of the renorenal reflexes to maintain low ERSNA to minimize sodium retention. High-sodium diet enhances the responsiveness of the renal sensory nerves, while low dietary sodium reduces the responsiveness of the renal sensory nerves, thus producing physiologically appropriate responses to maintain sodium balance. Increased renal ANG II reduces the responsiveness of the renal sensory nerves in physiological and pathophysiological conditions, including hypertension, congestive heart failure, and ischemia-induced acute renal failure. Impairment of inhibitory renorenal reflexes in these pathological states would contribute to the hypertension and sodium retention. When the inhibitory renorenal reflexes are suppressed, excitatory reflexes may prevail. Renal denervation reduces arterial pressure in experimental hypertension and in treatment-resistant hypertensive patients. The fall in arterial pressure is associated with a fall in muscle sympathetic nerve activity, suggesting that increased ARNA contributes to increased arterial pressure in these patients. Although removal of both renal sympathetic and afferent renal sensory nerves most likely contributes to the arterial pressure reduction initially, additional mechanisms may be involved in long-term arterial pressure reduction since sympathetic and sensory nerves reinnervate renal tissue in a similar time-dependent fashion following renal denervation. PMID:25411364

Dual specificity phosphatase 5 and 6 are oppositely regulated in human skeletal muscle by acute exercise.

PubMed

Pourteymour, Shirin; Hjorth, Marit; Lee, Sindre; Holen, Torgeir; Langleite, Torgrim M; Jensen, Jørgen; Birkeland, Kåre I; Drevon, Christian A; Eckardt, Kristin

2017-10-01

Physical activity promotes specific adaptations in most tissues including skeletal muscle. Acute exercise activates numerous signaling cascades including pathways involving mitogen-activated protein kinases (MAPKs) such as extracellular signal-regulated kinase (ERK)1/2, which returns to pre-exercise level after exercise. The expression of MAPK phosphatases (MKPs) in human skeletal muscle and their regulation by exercise have not been investigated before. In this study, we used mRNA sequencing to monitor regulation of MKPs in human skeletal muscle after acute cycling. In addition, primary human myotubes were used to gain more insights into the regulation of MKPs. The two ERK1/2-specific MKPs, dual specificity phosphatase 5 (DUSP5) and DUSP6, were the most regulated MKPs in skeletal muscle after acute exercise. DUSP5 expression was ninefold higher immediately after exercise and returned to pre-exercise level within 2 h, whereas DUSP6 expression was reduced by 43% just after exercise and remained below pre-exercise level after 2 h recovery. Cultured myotubes express both MKPs, and incubation with dexamethasone (Dex) mimicked the in vivo expression pattern of DUSP5 and DUSP6 caused by exercise. Using a MAPK kinase inhibitor, we showed that stimulation of ERK1/2 activity by Dex was required for induction of DUSP5 However, maintaining basal ERK1/2 activity was required for basal DUSP6 expression suggesting that the effect of Dex on DUSP6 might involve an ERK1/2-independent mechanism. We conclude that the altered expression of DUSP5 and DUSP6 in skeletal muscle after acute endurance exercise might affect ERK1/2 signaling of importance for adaptations in skeletal muscle during exercise. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

An "enigmatic" L-carnosine (β-alanyl-L-histidine)? Cell proliferative activity as a fundamental property of a natural dipeptide inherent to traditional antioxidant, anti-aging biological activities: balancing and a hormonally correct agent, novel patented oral therapy dosage formulation for mobility, skeletal muscle power and functional performance, hypothalamic-pituitary- brain relationship in health, aging and stress studies.

PubMed

Babizhayev, Mark A; Yegorov, Yegor E

2015-01-01

Hypothalamic releasing and inhibiting hormones are major neuroendocrine regulators of human body metabolism being driven directly to the anterior pituitary gland via hypothalamic-hypophyseal portal veins. The alternative physiological or therapeutic interventions utilizing the pharmaco-nutritional boost of imidazole-containing dipeptides (non-hydrolized oral form of carnosine, carcinine, N-acetylcarnosine lubricant eye drops) can maintain health, enhance physical exercise performance and prevent ageing. Carnosine (β-alanyl-L-histidine) is synthesized in mammalian skeletal muscle. There is an evidence that the release of carnosine from the skeletal muscle sarcomeres moieties during physical exercise affects autonomic neurotransmission and physiological functions. Carnosine released from skeletal muscle during exercise acts as a powerful afferent physiological signaling stimulus for hypothalamus, may be transported into the hypothalamic tuberomammillary nucleus (TMN), specifically to TMN-histamine neurons and hydrolyzed herewith via activities of carnosine-degrading enzyme (carnosinase 2) localized in situ. Through the colocalized enzymatic activity of Histidine decarboxylase in the histaminergic neurons, the resulting L-histidine may subsequently be converted into histamine, which could be responsible for the effects of carnosine on neurotransmission and physiological function. Carnosine and its imidazole-containing dipeptide derivatives are renowned for their anti-aging, antioxidant, membrane protective, metal ion chelating, buffering, anti-glycation/ transglycating activities used to prevent and treat a spectrum of age-related and metabolic diseases, such as neurodegenerative disease, sight threatening eye diseases, Diabetes mellitus and its complications, cancers and other disorders due to their wide spectrum biological activities. The precursor of carnosine (and related imidazole containing compounds) synthesis in skeletal muscles beta-alanine is used as the oral supplement by athletes to achieve the fine sporting art results due to the buffering activities of carnosine and its related imidazole- containing compounds which contribute to the maintenance of the acid-base balance in the acting muscles. This work originally emphasizes that overall data indicate the signaling activities of carnosine in skeletal and cardiac muscles switching on the mechanisms of exercise-induced telomere protection and point to the stress response and growth/cellular proliferation pathways as high-priority candidates for the ongoing studies and therapeutic concepts. The therapeutic interventions utilizing the specific oral formulation (Can-C Plus), timing dosing and pharmaco-nutritional boost of imidazolecontaining dipeptides can maintain health, enhance physical exercise performance and prevent aging. The patented therapeutic concept protects the existence of the interesting physiological major activities, better controls and therapeutic treatments for aging/age-related disorders (including age-related loss of muscle mass and muscle function) using carnosine dipeptide for cellular rejuvenation and manipulating telomeres and enzyme telomerase activity that may reduce some of the physiological declines that accompany aging.

Digital Health: Tracking Physiomes and Activity Using Wearable Biosensors Reveals Useful Health-Related Information

PubMed Central

Zhou, Gao; Zhou, Wenyu; Schüssler-Fiorenza Rose, Sophia Miryam; Perelman, Dalia; Colbert, Elizabeth; Runge, Ryan; Rego, Shannon; Sonecha, Ria; Datta, Somalee; McLaughlin, Tracey; Snyder, Michael P.

2017-01-01

A new wave of portable biosensors allows frequent measurement of health-related physiology. We investigated the use of these devices to monitor human physiological changes during various activities and their role in managing health and diagnosing and analyzing disease. By recording over 250,000 daily measurements for up to 43 individuals, we found personalized circadian differences in physiological parameters, replicating previous physiological findings. Interestingly, we found striking changes in particular environments, such as airline flights (decreased peripheral capillary oxygen saturation [SpO2] and increased radiation exposure). These events are associated with physiological macro-phenotypes such as fatigue, providing a strong association between reduced pressure/oxygen and fatigue on high-altitude flights. Importantly, we combined biosensor information with frequent medical measurements and made two important observations: First, wearable devices were useful in identification of early signs of Lyme disease and inflammatory responses; we used this information to develop a personalized, activity-based normalization framework to identify abnormal physiological signals from longitudinal data for facile disease detection. Second, wearables distinguish physiological differences between insulin-sensitive and -resistant individuals. Overall, these results indicate that portable biosensors provide useful information for monitoring personal activities and physiology and are likely to play an important role in managing health and enabling affordable health care access to groups traditionally limited by socioeconomic class or remote geography. PMID:28081144

"Physiology in the News": Using Press Releases to Enhance Lay Communication and Introduce Current Physiology Research to Undergraduates

ERIC Educational Resources Information Center

Kelly, Kevin L.; Poteracki, James M.; Steury, Michael D.; Wehrwein, Erica A.

2015-01-01

Michigan State University's senior-level undergraduate physiology capstone laboratory uses a simple exercise termed "Physiology in the News," to help students explore the current research within the field of physiology while also learning to communicate science in lay terms. "Physiology in the News" is an activity that charges…

Assessment of anxiety in open field and elevated plus maze using infrared thermography.

PubMed

Lecorps, Benjamin; Rödel, Heiko G; Féron, Christophe

2016-04-01

Due to their direct inaccessibility, affective states are classically assessed by gathering concomitant physiological and behavioral measures. Although such a dual approach to assess emotional states is frequently used in different species including humans, the invasiveness of procedures for physiological recordings particularly in smaller-sized animals strongly restricts their application. We used infrared thermography, a non-invasive method, to assess physiological arousal during open field and elevated plus maze tests in mice. By measuring changes in surface temperature indicative of the animals' emotional response, we aimed to improve the inherently limited and still controversial information provided by behavioral parameters commonly used in these tests. Our results showed significant and consistent thermal responses during both tests, in accordance with classical physiological responses occurring in stressful situations. Besides, we found correlations between these thermal responses and the occurrence of anxiety-related behaviors. Furthermore, initial temperatures measured at the start of each procedure (open field, elevated plus maze), which can be interpreted as a measure of the animals' initial physiological arousal, predicted the levels of activity and of anxiety-related behaviors displayed during the tests. Our results stress the strong link between physiological correlates of emotions and behaviors expressed during unconditioned fear tests. Copyright © 2016 Elsevier Inc. All rights reserved.

Dynamical analysis of uterine cell electrical activity model.

PubMed

Rihana, S; Santos, J; Mondie, S; Marque, C

2006-01-01

The uterus is a physiological system consisting of a large number of interacting smooth muscle cells. The uterine excitability changes remarkably with time, generally quiescent during pregnancy, the uterus exhibits forceful synchronized contractions at term leading to fetus expulsion. These changes characterize thus a dynamical system susceptible of being studied through formal mathematical tools. Multiple physiological factors are involved in the regulation process of this complex system. Our aim is to relate the physiological factors to the uterine cell dynamic behaviors. Taking into account a previous work presented, in which the electrical activity of a uterine cell is described by a set of ordinary differential equations, we analyze the impact of physiological parameters on the response of the model, and identify the main subsystems generating the complex uterine electrical activity, with respect to physiological data.

Hericium erinaceus (Yamabushitake): a unique resource for developing functional foods and medicines.

PubMed

Wang, Mingxing; Gao, Yang; Xu, Duoduo; Konishi, Tetsuya; Gao, Qipin

2014-12-01

Hericium erinaceus (HE) is a fungus inhabiting the mountainous areas of the northeast territories in Asia. HE has been used in traditional folk medicine and medicinal cuisine in China, Korea and Japan. Evidence has been adduced for a variety of physiological effects, including anti-aging, anti-cancer, anti-gastritis, and anti-metabolic disease properties. Hence, HE is an attractive target resource for developing not only medicines, but also functional foods. Basic studies on the physiological functions of HE and on the chemical identification of its active ingredients have progressed in recent decades. In this article, we provide an overview of the biochemical and pharmacological studies on HE, especially of its antitumor and neuroprotective functions, together with a survey of recent developments in the chemical analysis of its polysaccharides, which comprise its major active components.

Psychrophiles

NASA Astrophysics Data System (ADS)

Siddiqui, Khawar S.; Williams, Timothy J.; Wilkins, David; Yau, Sheree; Allen, Michelle A.; Brown, Mark V.; Lauro, Federico M.; Cavicchioli, Ricardo

2013-05-01

Psychrophilic (cold-adapted) microorganisms make a major contribution to Earth's biomass and perform critical roles in global biogeochemical cycles. The vast extent and environmental diversity of Earth's cold biosphere has selected for equally diverse microbial assemblages that can include archaea, bacteria, eucarya, and viruses. Underpinning the important ecological roles of psychrophiles are exquisite mechanisms of physiological adaptation. Evolution has also selected for cold-active traits at the level of molecular adaptation, and enzymes from psychrophiles are characterized by specific structural, functional, and stability properties. These characteristics of enzymes from psychrophiles not only manifest in efficient low-temperature activity, but also result in a flexible protein structure that enables biocatalysis in nonaqueous solvents. In this review, we examine the ecology of Antarctic psychrophiles, physiological adaptation of psychrophiles, and properties of cold-adapted proteins, and we provide a view of how these characteristics inform studies of astrobiology.

The anatomy and physiology of the locomotor system.

PubMed

Farley, Alistair; McLafferty, Ella; Hendry, Charles

Mobilisation is one of the activities of living. The term locomotor system refers to those body tissues and organs responsible for movement. Nurses and healthcare workers should be familiar with the body structures that enable mobilisation to assist those in their care with this activity. This article outlines the structure and function of the locomotor system, including the skeleton, joints, muscles and muscle attachments. Two common bone disorders, osteoporosis and osteoarthritis, are also considered.

The emerging role of flavonoid-rich cocoa and chocolate in cardiovascular health and disease.

PubMed

Engler, Mary B; Engler, Marguerite M

2006-03-01

Cocoa and chocolate have recently been found to be rich plant-derived sources of antioxidant flavonoids with beneficial cardiovascular properties. These favorable physiological effects include: antioxidant activity, vasodilation and blood pressure reduction, inhibition of platelet activity, and decreased inflammation. Increasing evidence from experimental and clinical studies using cocoa-derived products and chocolate suggest an important role for these high-flavanol-containing foods in heart and vascular protection.

Extreme rituals in a BDSM context: the physiological and psychological effects of the 'Dance of Souls'.

PubMed

Klement, Kathryn R; Lee, Ellen M; Ambler, James K; Hanson, Sarah A; Comber, Evelyn; Wietting, David; Wagner, Michael F; Burns, Valerie R; Cutler, Bert; Cutler, Nadine; Reid, Elwood; Sagarin, Brad J

2017-04-01

Participation in extreme rituals (e.g., fire-walking, body-piercing) has been documented throughout history. Motivations for such physically intense activities include religious devotion, sensation-seeking and social bonding. The present study aims to explore an extreme ritual within the context of bondage/discipline, dominance/submission and sadism/masochism (BDSM): the 'Dance of Souls', a 160-person ritual involving temporary piercings with weights or hooks attached and dancing to music provided by drummers. Through hormonal assays, behavioural observations and questionnaires administered before, during and after the Dance, we examine the physiological and psychological effects of the Dance, and the themes of spirituality, connectedness, transformation, release and community reported by dancers. From before to during the Dance, participants showed increases in physiological stress (measured by the hormone cortisol), self-reported sexual arousal, self-other overlap and decreases in psychological stress and negative affect. Results suggest that this group of BDSM practitioners engage in the Dance for a variety of reasons, including experiencing spirituality, deepening interpersonal connections, reducing stress and achieving altered states of consciousness.

Diving physiology of seabirds and marine mammals: Relevance, challenges and some solutions for field studies.

PubMed

Andrews, Russel D; Enstipp, Manfred R

2016-12-01

To fully understand how diving seabirds and marine mammals balance the potentially conflicting demands of holding their breath while living their lives underwater (and maintaining physiological homeostasis during exercise, feeding, growth, and reproduction), physiological studies must be conducted with animals in their natural environments. The purpose of this article is to review the importance of making physiological measurements on diving animals in field settings, while acknowledging the challenges and highlighting some solutions. The most extreme divers are great candidates for study, especially in a comparative and mechanistic context. However, physiological data are also required of a wide range of species for problems relating to other disciplines, in particular ecology and conservation biology. Physiological data help with understanding and predicting the outcomes of environmental change, and the direct impacts of anthropogenic activities. Methodological approaches that have facilitated the development of field-based diving physiology include the isolated diving hole protocol and the translocation paradigm, and while there are many techniques for remote observation, animal-borne biotelemetry, or "biologging", has been critical. We discuss issues related to the attachment of instruments, the retrieval of data and sensing of physiological variables, while also considering negative impacts of tagging. This is illustrated with examples from a variety of species, and an in-depth look at one of the best studied and most extreme divers, the emperor penguin (Aptenodytes forsteri). With a variety of approaches and high demand for data on the physiology of diving seabirds and marine mammals, the future of field studies is bright. Copyright © 2016 Elsevier Inc. All rights reserved.

Protease-Activated Receptors and other G-Protein-Coupled Receptors: the Melanoma Connection

PubMed Central

Rosero, Rebecca A.; Villares, Gabriel J.; Bar-Eli, Menashe

2016-01-01

The vast array of G-protein-coupled receptors (GPCRs) play crucial roles in both physiological and pathological processes, including vision, coagulation, inflammation, autophagy, and cell proliferation. GPCRs also affect processes that augment cell proliferation and metastases in many cancers including melanoma. Melanoma is the deadliest form of skin cancer, yet limited therapeutic modalities are available to patients with metastatic melanoma. Studies have found that both chemokine receptors and protease-activated receptors, both of which are GPCRs, are central to the metastatic melanoma phenotype and may serve as potential targets in novel therapies against melanoma and other cancers. PMID:27379162

Protease-Activated Receptors and other G-Protein-Coupled Receptors: the Melanoma Connection.

PubMed

Rosero, Rebecca A; Villares, Gabriel J; Bar-Eli, Menashe

2016-01-01

The vast array of G-protein-coupled receptors (GPCRs) play crucial roles in both physiological and pathological processes, including vision, coagulation, inflammation, autophagy, and cell proliferation. GPCRs also affect processes that augment cell proliferation and metastases in many cancers including melanoma. Melanoma is the deadliest form of skin cancer, yet limited therapeutic modalities are available to patients with metastatic melanoma. Studies have found that both chemokine receptors and protease-activated receptors, both of which are GPCRs, are central to the metastatic melanoma phenotype and may serve as potential targets in novel therapies against melanoma and other cancers.

Platelets: versatile effector cells in hemostasis, inflammation, and the immune continuum

PubMed Central

Vieira-de-Abreu, Adriana; Campbell, Robert A.; Weyrich, Andrew S.

2015-01-01

Platelets are chief effector cells in hemostasis. In addition, however, their specializations include activities and intercellular interactions that make them key effectors in inflammation and in the continuum of innate and adaptive immunity. This review focuses on the immune features of human platelets and platelets from experimental animals and on interactions between inflammatory, immune, and hemostatic activities of these anucleate but complex and versatile cells. The experimental findings and evidence for physiologic immune functions include previously unrecognized biologic characteristics of platelets and are paralleled by new evidence for unique roles of platelets in inflammatory, immune, and thrombotic diseases. PMID:21818701

Preparation of Single-cohort Colonies and Hormone Treatment of Worker Honeybees to Analyze Physiology Associated with Role and/or Endocrine System.

PubMed

Ueno, Takayuki; Kawasaki, Kiyoshi; Kubo, Takeo

2016-09-06

Honeybee workers are engaged in various tasks related to maintaining colony activity. The tasks of the workers change according to their age (age-related division of labor). Young workers are engaged in nursing the brood (nurse bees), while older workers are engaged in foraging for nectar and pollen (foragers). The physiology of the workers changes in association with this role shift. For example, the main function of the hypopharyngeal glands (HPGs) changes from the secretion of major royal jelly proteins (MRJPs) to the secretion of carbohydrate-metabolizing enzymes. Because worker tasks change as the workers age in typical colonies, it is difficult to discriminate the physiological changes that occur with aging from those that occur with the role shift. To study the physiological changes in worker tissues, including the HPGs, in association with the role shift, it would be useful to manipulate the honeybee colony population by preparing single-cohort colonies in which workers of almost the same age perform different tasks. Here we describe a detailed protocol for preparing single-cohort colonies for this analysis. Six to eight days after single-cohort colony preparation, precocious foragers that perform foraging tasks earlier than usual appear in the colony. Representative results indicated role-associated changes in HPG gene expression, suggesting role-associated HPG function. In addition to manipulating the colony population, analysis of the endocrine system is important for investigating role-associated physiology. Here, we also describe a detailed protocol for treating workers with 20-hydroxyecdysone (20E), an active form of ecdysone, and methoprene, a juvenile hormone analogue. The survival rate of treated bees was sufficient to examine gene expression in the HPGs. Gene expression changes were observed in response to 20E- and/or methoprene-treatment, suggesting that hormone treatments induce physiological changes of the HPGs. The protocol for hormone treatment described here is appropriate for examining hormonal effects on worker physiology.

Do Glucose and Caffeine Nasal Sprays Influence Exercise or Cognitive Performance?

PubMed

De Pauw, Kevin; Roelands, Bart; Van Cutsem, Jeroen; Decroix, Lieselot; Valente, Angelica; Taehee, Kim; Lettan, Robert B; Carrillo, Andres E; Meeusen, Romain

2017-10-01

Nasal spray (NAS) containing caffeine (CAF) or glucose (GLUC) activates sensory(motor) cortices. To investigate the influence of CAF or GLUC NAS on exercise and cognitive performance. Eleven male subjects (age 22 ± 2 y) performed a maximal cycle test and 2 familiarization and 3 experimental trials. Each trial included a 30-s Wingate test and a 30-min time-trial (TT) performance test interspersed by 15 min of rest. Before and after each exercise test a Stroop task was conducted. Placebo NAS with or without CAF or GLUC was provided before each exercise session and at each completed 25% of the TT. Exercise-performance, physiological, and cognitive measures were obtained. Magnitude-based inferences determined the likelihood that NAS solutions would be beneficial, trivial, or negative to exercise-performance measures based on the smallest worthwhile effect. Physiological and cognitive measures were analyzed using (non)parametric tests (P < .05). GLUC NAS substantially increased the average power output during the TT (very likely beneficial: 98%). No further worthwhile exercise-performance enhancements were found for both substances. In addition, no significant differences in physiological and cognitive measures were observed. In line with mouth rinsing, GLUC was shown to substantially enhance endurance performance, probably due to the activation of the olfactory pathway and/or extra-oral sweet-taste receptors. GLUC NAS enhances endurance performance, which indicates a novel administration route. The higher activity in sensory brain cortices probably elicited the ergogenic effect. However, no further physiological and cognitive changes occurred, indicating that higher doses of substrates might be required.

Insights into Substrate Specificity and Metal Activation of Mammalian Tetrahedral Aspartyl Aminopeptidase*

PubMed Central

Chen, Yuanyuan; Farquhar, Erik R.; Chance, Mark R.; Palczewski, Krzysztof; Kiser, Philip D.

2012-01-01

Aminopeptidases are key enzymes involved in the regulation of signaling peptide activity. Here, we present a detailed biochemical and structural analysis of an evolutionary highly conserved aspartyl aminopeptidase called DNPEP. We show that this peptidase can cleave multiple physiologically relevant substrates, including angiotensins, and thus may play a key role in regulating neuron function. Using a combination of x-ray crystallography, x-ray absorption spectroscopy, and single particle electron microscopy analysis, we provide the first detailed structural analysis of DNPEP. We show that this enzyme possesses a binuclear zinc-active site in which one of the zinc ions is readily exchangeable with other divalent cations such as manganese, which strongly stimulates the enzymatic activity of the protein. The plasticity of this metal-binding site suggests a mechanism for regulation of DNPEP activity. We also demonstrate that DNPEP assembles into a functionally relevant tetrahedral complex that restricts access of peptide substrates to the active site. These structural data allow rationalization of the enzyme's preference for short peptide substrates with N-terminal acidic residues. This study provides a structural basis for understanding the physiology and bioinorganic chemistry of DNPEP and other M18 family aminopeptidases. PMID:22356908

Physiological Response to Reward and Extinction Predicts Alcohol, Marijuana, and Cigarette Use Two Years Later

PubMed Central

Derefinko, Karen J.; Eisenlohr-Moul, Tory A.; Peters, Jessica R.; Roberts, Walter; Walsh, Erin C.; Milich, Richard; Lynam, Donald R.

2017-01-01

Background Physiological responses to reward and extinction are believed to represent the Behavioral Activation System (BAS) and Behavioral Inhibition System (BIS) constructs of Reinforcement Sensitivity Theory and underlie externalizing behaviors, including substance use. However, little research has examined these relations directly. Methods We assessed individuals’ cardiac pre-ejection periods (PEP) and electrodermal responses (EDR) during reward and extinction trials through the “Number Elimination Game” paradigm. Responses represented BAS and BIS, respectively. We then examined whether these responses provided incremental utility in the prediction of future alcohol, marijuana, and cigarette use. Results Zero-inflated Poisson (ZIP) regression models were used to examine the predictive utility of physiological BAS and BIS responses above and beyond previous substance use. Physiological responses accounted for incremental variance over previous use. Low BAS responses during reward predicted frequency of alcohol use at year 3. Low BAS responses during reward and extinction and high BIS responses during extinction predicted frequency of marijuana use at year 3. For cigarette use, low BAS response during extinction predicted use at year 3. Conclusions These findings suggest that the constructs of Reinforcement Sensitivity Theory, as assessed through physiology, contribute to the longitudinal maintenance of substance use. PMID:27306728

Gut feedback mechanisms and food intake: a physiological approach to slow carbohydrate bioavailability.

PubMed

Zhang, Genyi; Hasek, Like Y; Lee, Byung-Hoo; Hamaker, Bruce R

2015-04-01

Glycemic carbohydrates in foods are an important macronutrient providing the biological fuel of glucose for a variety of physiological processes. A classification of glycemic carbohydrates into rapidly digestible carbohydrate (RDC) and slowly digestible carbohydrate (SDC) has been used to specify their nutritional quality related to glucose homeostasis that is essential to normal functioning of the brain and critical to life. Although there have been many studies and reviews on slowly digestible starch (SDS) and SDC, the mechanisms of their slow digestion and absorption were mostly investigated from the material side without considering the physiological processes of their in vivo digestion, absorption, and most importantly interactions with other food components and the gastrointestinal tract. In this article, the physiological processes modulating the bioavailability of carbohydrates, specifically the rate and extent of their digestion and absorption as well as the related locations, in a whole food context, will be discussed by focusing on the activities of the gastrointestinal tract including glycolytic enzymes and glucose release, sugar sensing, gut hormones, and neurohormonal negative feedback mechanisms. It is hoped that a deep understanding of these physiological processes will facilitate the development of innovative dietary approaches to achieve desired carbohydrate or glucose bioavailability for improved health.

Network properties of interstitial cells of Cajal affect intestinal pacemaker activity and motor patterns, according to a mathematical model of weakly coupled oscillators.

PubMed

Wei, Ruihan; Parsons, Sean P; Huizinga, Jan D

2017-03-01

What is the central question of this study? What are the effects of interstitial cells of Cajal (ICC) network perturbations on intestinal pacemaker activity and motor patterns? What is the main finding and its importance? Two-dimensional modelling of the ICC pacemaker activity according to a phase model of weakly coupled oscillators showed that network properties (coupling strength between oscillators, frequency gradient and frequency noise) strongly influence pacemaker network activity and subsequent motor patterns. The model explains motor patterns observed in physiological conditions and provides predictions and testable hypotheses for effects of ICC loss and frequency modulation on the motor patterns. Interstitial cells of Cajal (ICC) are the pacemaker cells of gut motility and are associated with motility disorders. Interstitial cells of Cajal form a network, but the contributions of its network properties to gut physiology and dysfunction are poorly understood. We modelled an ICC network as a two-dimensional network of weakly coupled oscillators with a frequency gradient and showed changes over time in video and graphical formats. Model parameters were obtained from slow-wave-driven contraction patterns in the mouse intestine and pacemaker slow-wave activities from the cat intestine. Marked changes in propagating oscillation patterns (including changes from propagation to non-propagating) were observed by changing network parameters (coupling strength between oscillators, the frequency gradient and frequency noise), which affected synchronization, propagation velocity and occurrence of dislocations (termination of an oscillation). Complete uncoupling of a circumferential ring of oscillators caused the proximal and distal section to desynchronize, but complete synchronization was maintained with only a single oscillator connecting the sections with high enough coupling. The network of oscillators could withstand loss; even with 40% of oscillators lost randomly within the network, significant synchronization and anterograde propagation remained. A local increase in pacemaker frequency diminished anterograde propagation; the effects were strongly dependent on location, frequency gradient and coupling strength. In summary, the model puts forth the hypothesis that fundamental changes in oscillation patterns (ICC slow-wave activity or circular muscle contractions) can occur through physiological modulation of network properties. Strong evidence is provided to accept the ICC network as a system of coupled oscillators. © 2016 The Authors. Experimental Physiology © 2016 The Physiological Society.

Cysteine residue 911 in C-terminal tail of human BK(Ca)α channel subunit is crucial for its activation by carbon monoxide.

PubMed

Telezhkin, Vsevolod; Brazier, Stephen P; Mears, Ruth; Müller, Carsten T; Riccardi, Daniela; Kemp, Paul J

2011-06-01

The large conductance, voltage- and calcium-activated potassium channel, BK(Ca), is a known target for the gasotransmitter, carbon monoxide (CO). Activation of BK(Ca) by CO modulates cellular excitability and contributes to the physiology of a diverse array of processes, including vascular tone and oxygen-sensing. Currently, there is no consensus regarding the molecular mechanisms underpinning reception of CO by the BK(Ca). Here, employing voltage-clamped, inside-out patches from HEK293 cells expressing single, double and triple cysteine mutations in the BK(Ca) α-subunit, we test the hypothesis that CO regulation is conferred upon the channel by interactions with cysteine residues within the RCK2 domain. In physiological [Ca(2+)](i), all mutants carrying a cysteine substitution at position 911 (C911G) demonstrated significantly reduced CO sensitivity; the C911G mutant did not express altered Ca(2+)-sensitivity. In contrast, histidine residues in RCK1 domain, previously shown to ablate CO activation in low [Ca(2+)](i), actually increased CO sensitivity when [Ca(2+)](i) was in the physiological range. Importantly, cyanide, employed here as a substituent for CO at potential metal centres, occluded activation by CO; this effect was freely reversible. Taken together, these data suggest that a specific cysteine residue in the C-terminal domain, which is close to the Ca(2+) bowl but which is not involved in Ca(2+) activation, confers significant CO sensitivity to BK(Ca) channels. The rapid reversibility of CO and cyanide binding, coupled to information garnered from other CO-binding proteins, suggests that C911 may be involved in formation of a transition metal cluster which can bind and, thereafter, activate BK(Ca).

Assessing the Physiological Cost of Active Videogames (Xbox Kinect) Versus Sedentary Videogames in Young Healthy Males.

PubMed

Barry, Gillian; Tough, Daniel; Sheerin, Phillip; Mattinson, Oliver; Dawe, Rachael; Board, Elisabeth

2016-02-01

The aims of this study were twofold: (1) to compare the physiological costs of active videogames (AVGs) and sedentary videogames (SVGs) and (2) to compare the exercise intensities attained during AVGs with the exercise intensity criteria for moderate and vigorous physical activity, as stated in current physical activity recommendations for improving public health. Nineteen young males participated in the study (age, 23 ± 3 years; height, 178 ± 6 cm; weight, 78 ± 15 kg). Participants completed a maximum oxygen uptake ([Formula: see text]) test and a gaming session, including AVGs ("Reflex Ridge," "River Rush," and "Boxing" for the Microsoft [Redmond, WA] Kinect™) and SVGs ("FIFA 14" [Electronic Arts, Burnaby, BC, Canada] and "Call of Duty" [Activision, Santa Monica, CA]). Heart rate (HR) and oxygen uptake [Formula: see text]) were recorded continuously during all videogames. Rating of perceived exertion (RPE) was taken every 3 minutes during AVGs and SVGs. Energy expenditure (EE), expressed as metabolic equivalents (METs), was calculated. One MET was defined as the volume of oxygen consumed at rest in a seated position and is equal to 3.5 mL of O2/kg of body mass/minute. The exercise intensity for each game was expressed as a percentage of [Formula: see text] and percentage of age-predicted maximum HR (HRmax). Exercise intensity (percentage HRmax, percentage [Formula: see text], and RPE) and EE (METs) were significantly higher during active gaming compared with sedentary gameplay (P < 0.01). AVGs elicited moderate levels of exercise intensity (64-72 percent HRmax) in line with current recommended physical activity guidelines. Our results indicate AVGs provoke physiological responses equivalent to a moderate-intensity physical activity.

Physiological correlates to spontaneous physical activity variability in obese patients with already treated sleep apnea syndrome.

PubMed

Vivodtzev, Isabelle; Mendelson, Monique; Croteau, Marilie; Gorain, Sandy; Wuyam, Bernard; Tamisier, Renaud; Lévy, Patrick; Maltais, François; Pépin, Jean-Louis

2017-03-01

Physical activity is promoted in patients with sleep disorders and obesity. The aim of the present study was to assess physiological factors influencing objectively measured spontaneous physical activity in already treated patients for obstructive sleep apnea (OSA) by nocturnal continuous positive airway pressure (CPAP). Fifty-five patients (age = 53 ± 3 years; body mass index (BMI) = 38 ± 3 kg/m 2 ; compliance with CPAP >4 h/night) were prospectively included. Measurements were 5-day actigraphy with metabolic equivalent of task (METs) assessment, body composition, pulmonary function, quadriceps and respiratory muscle strength, exercise capacity (6-min walking distance and maximal aerobic capacity), as well as sleep parameters (sleepiness, duration, oxygen saturation, and micro-arousals during sleep) and quality of life (SF-36 questionnaire). As expected, the number of steps per day (6879 ± 2511) and mean intensity of physical activity (1.38 ± 0.15 METs) were below the recommendations for obese population. In age-adjusted stepwise regression models, peak oxygen consumption (VO 2 peak ) and peak dyspnea perception during incremental exercise test were independent predictors of the number of steps per day (r = 0.49, p = 0.001) although VO 2 peak and peak minute ventilation were independent predictors of intensity of physical activity (in METs/day; r = 0.49, p = 0.001). In severe obese patients with OSA, exercise capacity, ventilatory requirement, and dyspnea perception were main physiological components of physical activity. These results emphasize the need to consider specific training interventions that increase ability to perform intense physical activity in obese OSA.

Teaching Activities for Defensive Living and Emergency Preparedness. Education Modules.

ERIC Educational Resources Information Center

Peterson, Grit, Ed.; And Others

Designed for teaching a generalized program in emergency preparedness education, the eight units of the manual can be used together or alone in any course that teaches human response to emergency preparedness or in physical education, recreation, health, biology, physiology, or science classes. The guide includes an introduction and seven major…

Bioethics Cases and Issues: Enrichment for Social Science, Humanities, and Science Courses.

ERIC Educational Resources Information Center

Guyer, Ruth Levy; Dillon, Mary Lou; Anderson, Linda; Szobota, Lola

2000-01-01

Discusses the use of bioethics and bioethical dilemmas in different subject areas at the high school level by focusing on the case of Baby K. Includes the story of Baby K, classroom activities for U.S. history, 10th and 11th grade ethics, and anatomy and physiology. (CMK)

Genetic and metabolic variability in autotrophic and heterotrophic bacteria

NASA Technical Reports Server (NTRS)

Decicco, B. T.

1972-01-01

The studies to evaluate an organism's ability to maintain normal physiological activities over a long period of time in a bioregenerative system are presented. Studies reviewed include: heat tolerant mutants of Pseudomonas fluoresceins, virulence factors of the Staphylococci, and the effect of mutations on the virulence for man in common and ubiquitous microorganisms.

Is It Hot in Here? Thermoregulation and Homeostasis through an Exercise Activity

ERIC Educational Resources Information Center

Dean, Lewis G.; Breslin, Angela; Ross, Emma Z.

2014-01-01

Homeostasis, the control of an internal environment to maintain stable, relatively constant conditions, is a key concept in physiology. In endothermic species, including humans ("Homo sapiens"), the control of body temperature is fundamental to the control of a suitable internal environment. To help regulate core body temperature, the…

Effect of temperature on enzymatic and physiological factors related to chilling injury in carambola fruit (Averrhoa carambola L.).

PubMed

Pérez-Tello, G O; Silva-Espinoza, B A; Vargas-Arispuro, I; Briceño-Torres, B O; Martinez-Tellez, M A

2001-10-05

Three groups of carambola fruits (Averrhoa carambola L.) were stored at 2 and 10 degrees C (85-90% relative humidity). The major physicochemical, physiological, and enzymatic responses of fruit were measured in each group over a 30-day period: chilling injury index (CII), decay (%), intracuticular waxes, cuticle permeability, pulp firmness, weight loss, sucrose, fructose and glucose contents, ion electrolyte leakage in pulp (%), ethylene and carbon dioxide production rates, and the activities of peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) enzymes. CII values were statistically different at 2 and 10 degrees C, showing high significance with respect to sucrose content and weight loss (P < 0.05). Chilling injury included darkened ribs and skin desiccation. According to the CI symptom development, a possible relationship of POD and PPO activities was found at 2 degrees C. A significant sucrose content increase was observed at 10 degrees C. CI symptoms were associated with POD and PAL activities. Copyright 2001 Academic Press.

Role of pattern recognition receptors of the neurovascular unit in inflamm-aging.

PubMed

Wilhelm, Imola; Nyúl-Tóth, Ádám; Kozma, Mihály; Farkas, Attila E; Krizbai, István A

2017-11-01

Aging is associated with chronic inflammation partly mediated by increased levels of damage-associated molecular patterns, which activate pattern recognition receptors (PRRs) of the innate immune system. Furthermore, many aging-related disorders are associated with inflammation. PRRs, such as Toll-like receptors (TLRs) and nucleotide-binding oligomerization domain-like receptors (NLRs), are expressed not only in cells of the innate immune system but also in other cells, including cells of the neurovascular unit and cerebral vasculature forming the blood-brain barrier. In this review, we summarize our present knowledge about the relationship between activation of PRRs expressed by cells of the neurovascular unit-blood-brain barrier, chronic inflammation, and aging-related pathologies of the brain. The most important damage-associated molecular pattern-sensing PRRs in the brain are TLR2, TLR4, and NLR family pyrin domain-containing protein-1 and pyrin domain-containing protein-3, which are activated during physiological and pathological aging in microglia, neurons, astrocytes, and possibly endothelial cells and pericytes. Copyright © 2017 the American Physiological Society.

A critical review of 5-HT brain microdialysis and behavior.

PubMed

Rueter, L E; Fornal, C A; Jacobs, B L

1997-01-01

Serotonin (5-HT) has been implicated in many central nervous system-mediated functions including sleep, arousal, feeding, motor activity and the stress response. In order to help establish the precise role of 5-HT in physiology and behavior, in vivo microdialysis studies have sought to identify the conditions under which the release of 5-HT is altered. Extracellular 5-HT levels have been monitored in more than fifteen regions of the brain during a variety of spontaneous behaviors, and in response to several physiological, environmental, and behavioral manipulations. The vast majority of these studies found increases (30-100%) in 5-HT release in almost all brain regions studied. Since electrophysiological studies have shown that behavioral arousal is the primary determinant of brain serotonergic neuronal activity, we suggest that the increase in 5-HT release seen during a wide variety of experimental conditions is largely due to one factor, namely an increase in behavioral arousal/motor activity associated with the manipulation.

Effects of Exercise in Immersive Virtual Environments on Cortical Neural Oscillations and Mental State

PubMed Central

Vogt, Tobias; Herpers, Rainer; Askew, Christopher D.; Scherfgen, David; Strüder, Heiko K.; Schneider, Stefan

2015-01-01

Virtual reality environments are increasingly being used to encourage individuals to exercise more regularly, including as part of treatment those with mental health or neurological disorders. The success of virtual environments likely depends on whether a sense of presence can be established, where participants become fully immersed in the virtual environment. Exposure to virtual environments is associated with physiological responses, including cortical activation changes. Whether the addition of a real exercise within a virtual environment alters sense of presence perception, or the accompanying physiological changes, is not known. In a randomized and controlled study design, moderate-intensity Exercise (i.e., self-paced cycling) and No-Exercise (i.e., automatic propulsion) trials were performed within three levels of virtual environment exposure. Each trial was 5 minutes in duration and was followed by posttrial assessments of heart rate, perceived sense of presence, EEG, and mental state. Changes in psychological strain and physical state were generally mirrored by neural activation patterns. Furthermore, these changes indicated that exercise augments the demands of virtual environment exposures and this likely contributed to an enhanced sense of presence. PMID:26366305

Endocannabinoids and stress.

PubMed

Riebe, Caitlin J; Wotjak, Carsten T

2011-07-01

Endogenous cannabinoids play an important role in the physiology and behavioral expression of stress responses. Activation of the hypothalamic-pituitary-adrenal (HPA) axis, including the release of glucocorticoids, is the fundamental hormonal response to stress. Endocannabinoid (eCB) signaling serves to maintain HPA-axis homeostasis, by buffering basal activity as well as by mediating glucocorticoid fast feedback mechanisms. Following chronic stressor exposure, eCBs are also involved in physiological and behavioral habituation processes. Behavioral consequences of stress include fear and stress-induced anxiety as well as memory formation in the context of stress, involving contextual fear conditioning and inhibitory avoidance learning. Chronic stress can also lead to depression-like symptoms. Prominent in these behavioral stress responses is the interaction between eCBs and the HPA-axis. Future directions may differentiate among eCB signaling within various brain structures/neuronal subpopulations as well as between the distinct roles of the endogenous cannabinoid ligands. Investigation into the role of the eCB system in allostatic states and recovery processes may give insight into possible therapeutic manipulations of the system in treating chronic stress-related conditions in humans.

Effects of Exercise in Immersive Virtual Environments on Cortical Neural Oscillations and Mental State.

PubMed

Vogt, Tobias; Herpers, Rainer; Askew, Christopher D; Scherfgen, David; Strüder, Heiko K; Schneider, Stefan

2015-01-01

Virtual reality environments are increasingly being used to encourage individuals to exercise more regularly, including as part of treatment those with mental health or neurological disorders. The success of virtual environments likely depends on whether a sense of presence can be established, where participants become fully immersed in the virtual environment. Exposure to virtual environments is associated with physiological responses, including cortical activation changes. Whether the addition of a real exercise within a virtual environment alters sense of presence perception, or the accompanying physiological changes, is not known. In a randomized and controlled study design, moderate-intensity Exercise (i.e., self-paced cycling) and No-Exercise (i.e., automatic propulsion) trials were performed within three levels of virtual environment exposure. Each trial was 5 minutes in duration and was followed by posttrial assessments of heart rate, perceived sense of presence, EEG, and mental state. Changes in psychological strain and physical state were generally mirrored by neural activation patterns. Furthermore, these changes indicated that exercise augments the demands of virtual environment exposures and this likely contributed to an enhanced sense of presence.

Lipid Raft Redox Signaling: Molecular Mechanisms in Health and Disease

PubMed Central

Zhou, Fan; Katirai, Foad

2011-01-01

Abstract Lipid rafts, the sphingolipid and cholesterol-enriched membrane microdomains, are able to form different membrane macrodomains or platforms upon stimulations, including redox signaling platforms, which serve as a critical signaling mechanism to mediate or regulate cellular activities or functions. In particular, this raft platform formation provides an important driving force for the assembling of NADPH oxidase subunits and the recruitment of other related receptors, effectors, and regulatory components, resulting, in turn, in the activation of NADPH oxidase and downstream redox regulation of cell functions. This comprehensive review attempts to summarize all basic and advanced information about the formation, regulation, and functions of lipid raft redox signaling platforms as well as their physiological and pathophysiological relevance. Several molecular mechanisms involving the formation of lipid raft redox signaling platforms and the related therapeutic strategies targeting them are discussed. It is hoped that all information and thoughts included in this review could provide more comprehensive insights into the understanding of lipid raft redox signaling, in particular, of their molecular mechanisms, spatial-temporal regulations, and physiological, pathophysiological relevances to human health and diseases. Antioxid. Redox Signal. 15, 1043–1083. PMID:21294649

Differential responses of rabbit ventricular and atrial transient outward current (Ito) to the Ito modulator NS5806.

PubMed

Cheng, Hongwei; Cannell, Mark B; Hancox, Jules C

2017-03-01

Transient outward potassium current (I to ) in the heart underlies phase 1 repolarization of cardiac action potentials and thereby affects excitation-contraction coupling. Small molecule activators of I to may therefore offer novel treatments for cardiac dysfunction, including heart failure and atrial fibrillation. NS5806 has been identified as a prototypic activator of canine I to This study investigated, for the first time, actions of NS5806 on rabbit atrial and ventricular I to Whole cell patch-clamp recordings of I to and action potentials were made at physiological temperature from rabbit ventricular and atrial myocytes. 10  μ mol/L NS5806 increased ventricular I to with a leftward shift in I to activation and accelerated restitution. At higher concentrations, stimulation of I to was followed by inhibition. The EC 50 for stimulation was 1.6  μ mol/L and inhibition had an IC 50 of 40.7  μ mol/L. NS5806 only inhibited atrial I to (IC 50 of 18  μ mol/L) and produced a modest leftward shifts in I to activation and inactivation, without an effect on restitution. 10  μ mol/L NS5806 shortened ventricular action potential duration (APD) at APD 20 -APD 90 but prolonged atrial APD NS5806 also reduced atrial AP upstroke and amplitude, consistent with an additional atrio-selective effect on Na + channels. In contrast to NS5806, flecainide, which discriminates between Kv1.4 and 4.x channels, produced similar levels of inhibition of ventricular and atrial I to NS5806 discriminates between rabbit ventricular and atrial I to, with mixed activator and inhibitor actions on the former and inhibitor actions against the later. NS5806 may be of significant value for pharmacological interrogation of regional differences in native cardiac I to . © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Understanding key performance indicators for breast support: An analysis of breast support effects on biomechanical, physiological and subjective measures during running.

PubMed

Risius, Debbie; Milligan, Alexandra; Berns, Jason; Brown, Nicola; Scurr, Joanna

2017-05-01

To assess the effectiveness of breast support previous studies monitored breast kinematics and kinetics, subjective feedback, muscle activity (EMG), ground reaction forces (GRFs) and physiological measures in isolation. Comparing these variables within one study will establish the key performance variables that distinguish between breast supports during activities such as running. This study investigates the effects of changes in breast support on biomechanical, physiological and subjective measures during running. Ten females (34D) ran for 10 min in high and low breast supports, and for 2 min bare breasted (2.8 m·s -1 ). Breast and body kinematics, EMG, expired air and heart rate were recorded. GRFs were recorded during 10 m overground runs (2.8 m·s -1 ) and subjective feedback obtained after each condition. Of the 62 variables measured, 22 kinematic and subjective variables were influenced by changes in breast support. Willingness to exercise, time lag and superio-inferior breast velocity were most affected. GRFs, EMG and physiological variables were unaffected by breast support changes during running. Breast displacement reduction, although previously advocated, was not the most sensitive variable to breast support changes during running. Instead breast support products should be assessed using a battery of performance indicators, including the key kinematic and subjective variables identified here.

Physiological Strain in French Vineyard Workers Wearing Protective Equipment to Conduct Re-Entry Tasks in Humid Conditions.

PubMed

Grimbuhler, Sonia; Viel, Jean-François

2018-06-19

The proper use of personal protective equipment (PPE) plays an important role in reducing exposure to pesticides in vineyard farming activities, including re-entry tasks. However, discomfort from clothing systems may increase the physiological burden on workers. We compared the physiological burdens of vineyard workers wearing three different types of PPE during canopy management in field humid conditions while accounting for occupational, climatic, and geographical environments. The study was conducted in the Bordeaux vineyards of southern France during June 2012. A total of 42 workers from seven vineyards consented to field observations. The following PPE garments were randomly allocated: HF Estufa polyamide (Brisa®), Tyvek® Classic Plus, and Tychem® C Standard. Participant sociodemographic characteristics were collected using a structured questionnaire. Skin temperature and heart rate were monitored continuously using portable devices. Multivariate multilevel linear regression models were performed to account for the hierarchical structure of data. No significant difference was found for mean skin temperature during work. Regardless of the cardiac strain parameter considered, the Tyvek® Classic Plus garment produced the poorest results (P ≤ 0.03). Under the very humid conditions encountered during the field study, the thinness and breathability of the Tyvek® Classic Plus garment resulted in undergarment humidity, imposing additional physiological burden on vineyard workers. These results confirm that the idea of using generic coveralls in any farming activity is unsuitable. Compromises should be created between physiological costs and protection, depending on the agricultural task performed, the crop grown, and the environmental conditions encountered.

Proteins regulating the biosynthesis and inactivation of neuromodulatory fatty acid amides.

PubMed

Patricelli, M P; Cravatt, B F

2001-01-01

Fatty acid amides (FAAs) represent a growing family of biologically active lipids implicated in a diverse range of cellular and physiological processes. At present, two general types of fatty acid amides, the N-acylethanolamines (NAEs) and the fatty acid primary amides (FAPAs), have been identified as potential physiological neuromodulators/neurotransmitters in mammals. Representative members of these two subfamilies include the endocannabinoid NAE anandamide and the sleep-inducing FAPA oleamide. In this Chapter, molecular mechanisms proposed for the biosynthesis and inactivation of FAAs are critically evaluated, with an emphasis placed on the biochemical and cell biological properties of proteins thought to mediate these processes.

Characterization and Reclassification of Yeasts Used for Biological Control of Postharvest Diseases of Fruits and Vegetables

PubMed Central

McLaughlin, R. J.; Wilson, C. L.; Chalutz, E.; Kurtzman, C. P.; Fett, W. F.; Osman, S. F.

1990-01-01

In previous studies workers have shown that three yeast strains (strains US-7, 82, and 101) have biological control activity against various postharvest fungal pathogens of fruits and vegetables, including Penicillium rots of apples and citrus and Botrytis rot of apples. In these reports the researchers have described these strains as Debaryomyces hansenii (anamorph, Candida famata) or Candida sp. strains. In this study we performed additional physiological, DNA reassociation, and mannan characterization tests that clearly established a new taxonomic classification for these strains, Candida guilliermondii. We also propose amendment of the physiological test profile in the taxonomic description of C. guilliermondii. PMID:16348361

Hemodynamic and Thermal Responses to Head and Neck Cooling in Men and Women

NASA Technical Reports Server (NTRS)

Ku, Yu-Tsuan E.; Montgomery, Leslie D.; Carbo, Jorge E.; Webbon, Bruce W.

1995-01-01

Personal cooling systems are used to alleviate symptoms of multiple sclerosis and to prevent increased core temperature during daily activities. Configurations of these systems include passive ice vests and circulating liquid cooling garments (LCGs) in the forms of vests, cooling caps and combined head and neck cooling systems. However, little information is available oil the amount or heat that can be extracted from the body with these systems or the physiologic changes produced by routine operation of these systems. The objective of this study was to determine the operating characteristics and the physiologic change, produced by short term use of one commercially available thermal control system.

Spacelab Life Sciences 1 - The stepping stone

NASA Technical Reports Server (NTRS)

Dalton, B. P.; Leon, H.; Hogan, R.; Clarke, B.; Tollinger, D.

1988-01-01

The Spacelab Life Sciences (SLS-1) mission scheduled for launch in March 1990 will study the effects of microgravity on physiological parameters of humans and animals. The data obtained will guide equipment design, performance of activities involving the use of animals, and prediction of human physiological responses during long-term microgravity exposure. The experiments planned for the SLS-1 mission include a particulate-containment demonstration test, integrated rodent experiments, jellyfish experiments, and validation of the small-mass measuring instrument. The design and operation of the Research Animal Holding Facility, General-Purpose Work Station, General-Purpose Transfer Unit, and Animal Enclosure Module are discussed and illustrated with drawings and diagrams.

Tree physiology research in a changing world.

PubMed

Kaufmann, Merrill R.; Linder, Sune

1996-01-01

Changes in issues and advances in methodology have contributed to substantial progress in tree physiology research during the last several decades. Current research focuses on process interactions in complex systems and the integration of processes across multiple spatial and temporal scales. An increasingly important challenge for future research is assuring sustainability of production systems and forested ecosystems in the face of increased demands for natural resources and human disturbance of forests. Meeting this challenge requires significant shifts in research approach, including the study of limitations of productivity that may accompany achievement of system sustainability, and a focus on the biological capabilities of complex land bases altered by human activity.

Relationship between physiological measurements (SFG -scope for growth-) and the functionality of the digestive gland in Mytilus galloprovincialis.

PubMed

Albentosa, Marina; Sánchez-Hernández, Miriam; Campillo, Juan Antonio; Moyano, Francisco Javier

2012-11-01

The present study was aimed to establish the relationship between the functionality of the digestive gland and physiological rates including SFG (scope for growth) in wild mussels, Mytilus galloprovincilis. The experimental set-up consisted in the evaluation of changes in the morphology of the gland, as well as in the activity of some key digestive enzymes (amylase, laminarinase, cellulase and protease) within a broad range of SFG obtained through manipulation of food ration. The higher SFG values were correlated to an increase in both the size of the digestive gland and the activities of enzymes when expressed in relation to individual. In contrast, no clear relations were observed when the activity of enzymes was expressed in relation to soluble protein, with the exception to amylase. The higher protease activities measured in mussels showing lower SFG may reflect an initial stage of catabolic processes intended to compensate the energy deficit produced by food restriction. The potential use of parameters measured in digestive glands in studies of marine pollution was discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Metabolomic, enzymatic, and histochemical analyzes of cassava roots during postharvest physiological deterioration.

PubMed

Uarrota, Virgílio Gavicho; Maraschin, Marcelo

2015-11-05

Under postharvest physiological deterioration cassava root tubers alter the expression of biosynthetic pathways of certain primary and secondary metabolites, as well as the activity of some scavenging enzymes. Therefore, in this study we hypothesized that cassava cultivars differ as to their physiological responses to deterioration and their biochemical profiles can be an indicative of the tolerance or susceptibility to deterioration. The results corroborate the working hypothesis, revealing that high Levels of phenolic acids, scopoletin, carotenoids, proteins, and augmented activities of guaiacol peroxidase and hydrogen peroxide in non-stored cassava roots can be used as potential biomarkers of cassava deterioration. Cassava physiological deterioration depends on cultivar and many compounds are up and downregulated during storage time. Secondary metabolites, enzymes, scopoletin, scavenging reactive oxygen species, and acidic polysaccharides are activated as responses to the physiological stress induced in root tubers.

The Effects Of An Exercise Physiology Program on Physical Fitness Variables, Body Satisfaction, and Physiology Knowledge.

ERIC Educational Resources Information Center

Perry, Arlette C.; Rosenblatt, Evelyn S.; Kempner, Lani; Feldman, Brandon B.; Paolercio, Maria A.; Van Bemden, Angie L.

2002-01-01

Examined the effects of an exercise physiology program on high school students' physical fitness, body satisfaction, and physiology knowledge. Intervention students received exercise physiology theory and active aerobic and resistance exercise within their biology course. Data from student surveys and measurements indicated that the integrated…

Nuclear localization of matrix metalloproteinases.

PubMed

Mannello, Ferdinando; Medda, Virginia

2012-03-01

Matrix metalloproteinases (MMPs) were originally identified as matrixin proteases that act in the extracellular matrix. Recent works have uncovered nontraditional roles for MMPs in the extracellular space as well as in the cytosol and nucleus. There is strong evidence that subspecialized and compartmentalized matrixins participate in many physiological and pathological cellular processes, in which they can act as both degradative and regulatory proteases. In this review, we discuss the transcriptional and translational control of matrixin expression, their regulation of intracellular sorting, and the structural basis of activation and inhibition. In particular, we highlight the emerging roles of various matrixin forms in diseases. The activity of matrix metalloproteinases is regulated at several levels, including enzyme activation, inhibition, complex formation and compartmentalization. Most MMPs are secreted and have their function in the extracellular environment. MMPs are also found inside cells, both in the nucleus, cytosol and organelles. The role of intracellular located MMPs is still poorly understood, although recent studies have unraveled some of their functions. The localization, activation and activity of MMPs are regulated by their interactions with other proteins, proteoglycan core proteins and / or their glycosaminoglycan chains, as well as other molecules. Complexes formed between MMPs and various molecules may also include interactions with noncatalytic sites. Such exosites are regions involved in substrate processing, localized outside the active site, and are potential binding sites of specific MMP inhibitors. Knowledge about regulation of MMP activity is essential for understanding various physiological processes and pathogenesis of diseases, as well as for the development of new MMP targeting drugs. Copyright © 2011 Elsevier GmbH. All rights reserved.

Publications of the Space Physiology and Countermeasures Program, Neuroscience Discipline: 1980-1990

NASA Technical Reports Server (NTRS)

Dickson, Katherine J.; Wallace-Robinson, Janice; Powers, Janet V.; Hess, Elizabeth

1992-01-01

A 10-year cumulative bibliography of publications resulting from research supported by the neuroscience discipline of the space physiology and countermeasures program of NASA's Life Sciences Division is provided. Primary subjects included in this bibliography are space motion sickness; vestibular performance, posture, and motor coordination; vestibular physiology; central and peripheral nervous system physiology; and general performance and methodologies. General physiology references are also included.

Physiology, ecology and industrial applications of aroma formation in yeast

PubMed Central

Dzialo, Maria C; Park, Rahel; Steensels, Jan; Lievens, Bart; Verstrepen, Kevin J

2017-01-01

Abstract Yeast cells are often employed in industrial fermentation processes for their ability to efficiently convert relatively high concentrations of sugars into ethanol and carbon dioxide. Additionally, fermenting yeast cells produce a wide range of other compounds, including various higher alcohols, carbonyl compounds, phenolic compounds, fatty acid derivatives and sulfur compounds. Interestingly, many of these secondary metabolites are volatile and have pungent aromas that are often vital for product quality. In this review, we summarize the different biochemical pathways underlying aroma production in yeast as well as the relevance of these compounds for industrial applications and the factors that influence their production during fermentation. Additionally, we discuss the different physiological and ecological roles of aroma-active metabolites, including recent findings that point at their role as signaling molecules and attractants for insect vectors. PMID:28830094

A Physiologically Based Model of Orexinergic Stabilization of Sleep and Wake

PubMed Central

Fulcher, Ben D.; Phillips, Andrew J. K.; Postnova, Svetlana; Robinson, Peter A.

2014-01-01

The orexinergic neurons of the lateral hypothalamus (Orx) are essential for regulating sleep-wake dynamics, and their loss causes narcolepsy, a disorder characterized by severe instability of sleep and wake states. However, the mechanisms through which Orx stabilize sleep and wake are not well understood. In this work, an explanation of the stabilizing effects of Orx is presented using a quantitative model of important physiological connections between Orx and the sleep-wake switch. In addition to Orx and the sleep-wake switch, which is composed of mutually inhibitory wake-active monoaminergic neurons in brainstem and hypothalamus (MA) and the sleep-active ventrolateral preoptic neurons of the hypothalamus (VLPO), the model also includes the circadian and homeostatic sleep drives. It is shown that Orx stabilizes prolonged waking episodes via its excitatory input to MA and by relaying a circadian input to MA, thus sustaining MA firing activity during the circadian day. During sleep, both Orx and MA are inhibited by the VLPO, and the subsequent reduction in Orx input to the MA indirectly stabilizes sustained sleep episodes. Simulating a loss of Orx, the model produces dynamics resembling narcolepsy, including frequent transitions between states, reduced waking arousal levels, and a normal daily amount of total sleep. The model predicts a change in sleep timing with differences in orexin levels, with higher orexin levels delaying the normal sleep episode, suggesting that individual differences in Orx signaling may contribute to chronotype. Dynamics resembling sleep inertia also emerge from the model as a gradual sleep-to-wake transition on a timescale that varies with that of Orx dynamics. The quantitative, physiologically based model developed in this work thus provides a new explanation of how Orx stabilizes prolonged episodes of sleep and wake, and makes a range of experimentally testable predictions, including a role for Orx in chronotype and sleep inertia. PMID:24651580

Psychosocial versus physiological stress – meta-analyses on deactivations and activations of the neural correlates of stress reactions

PubMed Central

Kogler, Lydia; Mueller, Veronika I.; Chang, Amy; Eickhoff, Simon B.; Fox, Peter T.; Gur, Ruben C.; Derntl, Birgit

2015-01-01

Stress is present in everyday life in various forms and situations. Two stressors frequently investigated are physiological and psychosocial stress. Besides similar subjective and hormonal responses, it has been suggested that they also share common neural substrates. The current study used activation-likelihood-estimation meta-analysis to test this assumption by integrating results of previous neuroimaging studies on stress processing. Reported results are cluster-level FWE corrected. The inferior frontal gyrus (IFG) and the anterior insula (AI) were the only regions that demonstrated overlapping activation for both stressors. Analysis of physiological stress showed consistent activation of cognitive and affective components of pain processing such as the insula, striatum, or the middle cingulate cortex. Contrarily, analysis across psychosocial stress revealed consistent activation of the right superior temporal gyrus and deactivation of the striatum. Notably, parts of the striatum appeared to be functionally specified: the dorsal striatum was activated in physiological stress, whereas the ventral striatum was deactivated in psychosocial stress. Additional functional connectivity and decoding analyses further characterized this functional heterogeneity and revealed higher associations of the dorsal striatum with motor regions and of the ventral striatum with reward processing. Based on our meta-analytic approach, activation of the IFG and the AI seems to indicate a global neural stress reaction. While physiological stress activates a motoric fight-or-flight reaction, during psychosocial stress attention is shifted towards emotion regulation and goal-directed behavior, and reward processing is reduced. Our results show the significance of differentiating physiological and psychosocial stress in neural engagement. Furthermore, the assessment of deactivations in addition to activations in stress research is highly recommended. PMID:26123376

Review of Four Years of Literature (1985, 1986, 1987 and 1988) for the Physiological and Psychological Effects of the Nuclear/Biological/Chemical and Extended Operations on Soldier Performance Program

DTIC Science & Technology

1988-12-30

LIMITING ACTIVATED ZOLUTION OF HYPOCHLORITE), SADS (SURFACE ACTIVE DISPLACEMENT SYSTEMS ), SACRIFICIAL COAT!ý:GS, MICRO EMULSIONS , DS2, STB SLURRY...CURRENT SYSTEMS AND THOSE IN DEVELOPMENT WITH NOT MEET ALL DECONTAMINATION NEEDS. ITEMS TO BE FIELDED WILL INCLUDE: AN EMULSION BSED DECONTAMINATION...DECONTAMINATION SYSTEM FOR AIRCRAFT EXTERIORS; MICROEMULSIONS CONTAINING REACTIVE DECONTAMINANTS (FORMULATION, EFFICACY, AND 181 OPTIMIZATION); COOLING OF

Life in the sea of plenty: Seasonal and regional comparison of physiological performance of Euphausia hanseni in the northern Benguela upwelling system

NASA Astrophysics Data System (ADS)

Werner, Thorsten; Buchholz, Cornelia; Buchholz, Friedrich

2015-09-01

Variability in upwelling events may lead to periods of constrained food availability in the northern Benguela upwelling system (NBUS), thereby affecting the physiological state and metabolic activity of euphausiids. Most attention has so far been paid to seasonal effects but little is known about regional variability. Metabolic activity (expressed by respiration and excretion rates) and physiological state (expressed by reproductive effort and moult activity) in Euphausia hanseni were examined at different stations during austral summer (minimum upwelling) and austral winter (maximum upwelling). Overall, regional differences in physiological state, influencing metabolic activity, were greater than seasonal ones, indicating favourable conditions for growth and reproduction year-round. Higher respiration rates were found for females in more advanced stages of sexual development. Moult stage did not affect oxygen consumption rates, however. The physiological state of E. hanseni at the time of capture may serve as a meaningful indicator of the associated hydrographic conditions in the NBUS, to be further used in eco-system analysis on seasonal or long-term time scales. A latitudinal comparison of species highlights the extraordinary physiological plasticity of euphausiids.

Timing matters: the interval between acute stressors within chronic mild stress modifies behavioral and physiologic stress responses in male rats.

PubMed

Cavigelli, Sonia A; Bao, Alexander D; Bourne, Rebecca A; Caruso, Michael J; Caulfield, Jasmine I; Chen, Mary; Smyth, Joshua M

2018-04-12

Chronic mild stress can lead to negative health outcomes. Frequency, duration, and intensity of acute stressors can affect health-related processes. We tested whether the temporal pattern of daily acute stressors (clustered or dispersed across the day) affects depression-related physiology. We used a rodent model to keep stressor frequency, duration, and intensity constant, and experimentally manipulated the temporal pattern of acute stressors delivered during the active phase of the day. Adult male Sprague-Dawley rats were exposed to one of three chronic mild stress groups: Clustered: stressors that occurred within 1 hour of each other (n = 21), Dispersed: stressors that were spread out across the active phase (n = 21), and Control: no stressors presented (n = 21). Acute mild stressors included noise, strobe lights, novel cage, cage tilt, wet bedding, and water immersion. Depression-related outcomes included: sucrose preference, body weight, circulating glucocorticoid (corticosterone) concentration after a novel acute stressor and during basal morning and evening times, and endotoxin-induced circulating interleukin-6 concentrations. Compared to control rats, those in the Clustered group gained less weight, consumed less sucrose, had a blunted acute corticosterone response, and an accentuated acute interleukin-6 response. Rats in the Dispersed group had an attenuated corticosterone decline during the active period and after an acute stressor compared to the Control group. During a chronic mild stress experience, the temporal distribution of daily acute stressors affected health-related physiologic processes. Regular exposure to daily stressors in rapid succession may predict more depression-related symptoms, whereas exposure to stressors dispersed throughout the day may predict diminished glucocorticoid negative feedback.

Analysis of clock-regulated genes in Neurospora reveals widespread posttranscriptional control of metabolic potential

PubMed Central

Hurley, Jennifer M.; Dasgupta, Arko; Emerson, Jillian M.; Zhou, Xiaoying; Ringelberg, Carol S.; Knabe, Nicole; Lipzen, Anna M.; Lindquist, Erika A.; Daum, Christopher G.; Barry, Kerrie W.; Grigoriev, Igor V.; Smith, Kristina M.; Galagan, James E.; Bell-Pedersen, Deborah; Freitag, Michael; Cheng, Chao; Loros, Jennifer J.; Dunlap, Jay C.

2014-01-01

Neurospora crassa has been for decades a principal model for filamentous fungal genetics and physiology as well as for understanding the mechanism of circadian clocks. Eukaryotic fungal and animal clocks comprise transcription-translation–based feedback loops that control rhythmic transcription of a substantial fraction of these transcriptomes, yielding the changes in protein abundance that mediate circadian regulation of physiology and metabolism: Understanding circadian control of gene expression is key to understanding eukaryotic, including fungal, physiology. Indeed, the isolation of clock-controlled genes (ccgs) was pioneered in Neurospora where circadian output begins with binding of the core circadian transcription factor WCC to a subset of ccg promoters, including those of many transcription factors. High temporal resolution (2-h) sampling over 48 h using RNA sequencing (RNA-Seq) identified circadianly expressed genes in Neurospora, revealing that from ∼10% to as much 40% of the transcriptome can be expressed under circadian control. Functional classifications of these genes revealed strong enrichment in pathways involving metabolism, protein synthesis, and stress responses; in broad terms, daytime metabolic potential favors catabolism, energy production, and precursor assembly, whereas night activities favor biosynthesis of cellular components and growth. Discriminative regular expression motif elicitation (DREME) identified key promoter motifs highly correlated with the temporal regulation of ccgs. Correlations between ccg abundance from RNA-Seq, the degree of ccg-promoter activation as reported by ccg-promoter–luciferase fusions, and binding of WCC as measured by ChIP-Seq, are not strong. Therefore, although circadian activation is critical to ccg rhythmicity, posttranscriptional regulation plays a major role in determining rhythmicity at the mRNA level. PMID:25362047

Pharmacology Risk Report

NASA Technical Reports Server (NTRS)

2010-01-01

It seems very likely that the actions of administered drugs on crewmembers during spaceflight are different than they are on Earth, but even after more than 40 years of spaceflight experience, the answers to most questions about medication use during missions remain unanswered. Use of medications with insufficient knowledge about their actual activities may result in inadequate treatment and may even reduce performance and well-being in particular circumstances. There is evidence that this has already occurred during and immediately after spaceflights. The spaceflight pharmaceutical activity knowledge base must be improved to enable flight surgeons and crewmembers to make better decisions about using pharmaceuticals inflight. The spaceflight environment induces changes in human physiology, and these changes have been the subject of much study over the past few decades. These studies are confounded by the small number of potential subjects, as well by the inability to separate the different stressors of spaceflight (radiation exposure from microgravity, for example). In every physiological system, the details of spaceflight-induced physiological changes are not well understood. Despite this fact, crewmembers are treated with pharmaceuticals to reduce or prevent medical problems, with insufficient information as to drug function on their altered physiological systems. There are two major concerns about pharmaceutical use in the unusual environment of spaceflight. The actions of pharmaceuticals on physiology altered by a spaceflight environment are currently assumed to be the same as the actions in terrestrial use. This has yet to be established. The wide range of physiological systems altered by spaceflight and the degree of change experienced in some of them make it very likely that alterations in pharmaceutical action will be seen. As the duration of missions lengthens to include more distant exploration, it becomes more likely that problems will be encountered. Secondly, the integrity of stored pharmaceuticals must be established to ensure that adequate amounts of active compounds are available in each dose and that degradation to toxic compounds is minimized. This risk is also dependent on mission duration, since longer missions will require that drugs be stored much longer than their usual terrestrial shelf-lives.

Gene Expression Profiling in the Hibernating Primate, Cheirogaleus Medius

PubMed Central

Faherty, Sheena L.; Villanueva-Cañas, José Luis; Klopfer, Peter H.; Albà, M. Mar; Yoder, Anne D.

2016-01-01

Hibernation is a complex physiological response that some mammalian species employ to evade energetic demands. Previous work in mammalian hibernators suggests that hibernation is activated not by a set of genes unique to hibernators, but by differential expression of genes that are present in all mammals. This question of universal genetic mechanisms requires further investigation and can only be tested through additional investigations of phylogenetically dispersed species. To explore this question, we use RNA-Seq to investigate gene expression dynamics as they relate to the varying physiological states experienced throughout the year in a group of primate hibernators—Madagascar’s dwarf lemurs (genus Cheirogaleus). In a novel experimental approach, we use longitudinal sampling of biological tissues as a method for capturing gene expression profiles from the same individuals throughout their annual hibernation cycle. We identify 90 candidate genes that have variable expression patterns when comparing two active states (Active 1 and Active 2) with a torpor state. These include genes that are involved in metabolic pathways, feeding behavior, and circadian rhythms, as might be expected to correlate with seasonal physiological state changes. The identified genes appear to be critical for maintaining the health of an animal that undergoes prolonged periods of metabolic depression concurrent with the hibernation phenotype. By focusing on these differentially expressed genes in dwarf lemurs, we compare gene expression patterns in previously studied mammalian hibernators. Additionally, by employing evolutionary rate analysis, we find that hibernation-related genes do not evolve under positive selection in hibernating species relative to nonhibernators. PMID:27412611

Physiological and neural correlates of worry and rumination: Support for the contrast avoidance model of worry.

PubMed

Steinfurth, Elisa C K; Alius, Manuela G; Wendt, Julia; Hamm, Alfons O

2017-02-01

The current experiments tested neural and physiological correlates of worry and rumination in comparison to thinking about neutral events. According to the avoidance model-stating that worry is a strategy to reduce intense emotions-physiological and neurobiological activity during worried thinking should not differ from activation during neutral thinking. According to the contrast avoidance model-stating that worry is a strategy to reduce abrupt shifts of emotions-activity should be increased. To test these competing models, we induced worry and neutral thinking in healthy participants using personal topics. A rumination condition was added to investigate the specificity of changes induced by the mental process. Two experiments were conducted assessing the effects on different response levels: (1) neural activation using fMRI, and (2) physiological response mobilization using startle and autonomic measures. During worry, participants showed a potentiated startle response and BOLD activity indicative of emotional network activation. These data partly support the contrast avoidance model of worry. Both mental processes showed elevated activity in a common network referred to as default network indicating self-referential activity. © 2016 Society for Psychophysiological Research.

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.

The hidden side of drug action: Brain temperature changes induced by neuroactive drugs

PubMed Central

Kiyatkin, Eugene A.

2013-01-01

Rationale Most neuroactive drugs affect brain metabolism as well as systemic and cerebral blood flow, thus altering brain temperature. Although this aspect of drug action usually remains in the shadows, drug-induced alterations in brain temperature reflect their metabolic neural effects and affect neural activity and neural functions. Objectives Here, I review brain temperature changes induced by neuroactive drugs, which are used therapeutically (general anesthetics), as a research tool (dopamine agonists and antagonists), and self-administered to induce desired psychic effects (cocaine, methamphetamine, ecstasy). I consider the mechanisms underlying these temperature fluctuations and their influence on neural, physiological, and behavioral effects of these drugs. Results By interacting with neural mechanisms regulating metabolic activity and heat exchange between the brain and the rest of the body, neuroactive drugs either increase or decrease brain temperatures both within (35-39°C) and exceeding the range of physiological fluctuations. These temperature effects differ drastically depending upon the environmental conditions and activity state during drug administration. This state-dependence is especially important for drugs of abuse that are usually taken by humans during psycho-physiological activation and in environments that prevent proper heat dissipation from the brain. Under these conditions, amphetamine-like stimulants induce pathological brain hyperthermia (>40°C) associated with leakage of the blood-brain barrier and structural abnormalities of brain cells. Conclusions The knowledge on brain temperature fluctuations induced by neuroactive drugs provides new information to understand how they influence metabolic neural activity, why their effects depend upon the behavioral context of administration, and the mechanisms underlying adverse drug effects including neurotoxicity PMID:23274506

Juicy lemons for measuring basic empathic resonance.

PubMed

Hagenmuller, Florence; Rössler, Wulf; Wittwer, Amrei; Haker, Helene

2014-10-30

Watch or even think of someone biting into a juicy lemon and your saliva will flow. This is a phenomenon of resonance, best described by the Perception-Action Model, where a physiological state in a person is activated through observation of this state in another. Within a broad framework of empathy, including manifold abilities depending on the Perception-Action link, resonance has been proposed as one physiological substrate for empathy. Using 49 healthy subjects, we developed a standardized salivation paradigm to assess empathic resonance at the autonomic level. Our results showed that this physiological resonance correlated positively with self-reported empathic concern. The salivation test, delivered an objective and continuous measure, was simple to implement in terms of setup and instruction, and could not easily be unintentionally biased or intentionally manipulated by participants. Therefore, these advantages make such a test a useful tool for assessing empathy-related abilities in psychiatric populations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Influence of Photoperiod on Hormones, Behavior, and Immune Function

PubMed Central

Walton, James C.; Weil, Zachary M.; Nelson, Randy J.

2011-01-01

Photoperiodism is the ability of plants and animals to measure environmental day length to ascertain time of year. Central to the evolution of photoperiodism in animals is the adaptive distribution of energetically challenging activities across the year to optimize reproductive fitness while balancing the energetic tradeoffs necessary for seasonally- appropriate survival strategies. The ability to accurately predict future events requires endogenous mechanisms to permit physiological anticipation of annual conditions. Day length provides a virtually noise free environmental signal to monitor and accurately predict time of the year. In mammals, melatonin provides the hormonal signal transducing day length. Duration of pineal melatonin is inversely related to day length and its secretion drives enduring changes in many physiological systems, including the HPA, HPG, and brain-gut axes, the autonomic nervous system, and the immune system. Thus, melatonin is the fulcrum mediating redistribution of energetic investment among physiological processes to maximize fitness and survival. PMID:21156187

Behaviour, physiology and experience of pathological laughing and crying in amyotrophic lateral sclerosis.

PubMed

Olney, Nicholas T; Goodkind, Madeleine S; Lomen-Hoerth, Catherine; Whalen, Patrick K; Williamson, Craig A; Holley, Deborah E; Verstaen, Alice; Brown, Laurel M; Miller, Bruce L; Kornak, John; Levenson, Robert W; Rosen, Howard J

2011-12-01

Pathological laughing and crying is a disorder of emotional expression seen in a number of neurological diseases. The aetiology is poorly understood, but clinical descriptions suggest a disorder of emotion regulation. The goals of this study were: (i) to characterize the subjective, behavioural and physiological emotional reactions that occur during episodes of pathological laughing and crying; (ii) to compare responses during these episodes to those that occur when emotions are elicited under standard conditions (watching sad and amusing emotional films, being startled); and (iii) to examine the ability of patients with this disorder to regulate their emotions under standardized conditions. Twenty-one patients with pathological laughing and crying due to amyotrophic lateral sclerosis and 14 with amyotrophic lateral sclerosis but no pathological laughing and crying were studied. Emotional measures included self-reported emotional experience, video recordings of facial reactivity and peripheral physiological responses (skin conductance, heart rate and somatic activity). Nineteen of the 21 patients with histories of pathological laughing and crying had at least one episode in the laboratory that they agreed constituted pathological laughing or crying (a total of 56 episodes were documented). Compared with viewing sad and amusing films, the episodes were associated with greater facial and physiological activation. Contrary to many clinical descriptions, episodes were often induced by contextually appropriate stimuli and associated with strong experiences of emotion that were consistent with the display. When instructed to regulate their facial responses to emotion-eliciting films, patients with pathological laughing and crying showed impairments compared with patients who did not have a history of this disorder. These findings support the idea that pathological laughing and crying represents activation of all channels of emotional responding (i.e. behavioural, physiological and subjective). Furthermore, they support previously advanced theories that, rather than being associated with general emotional hyperreactivity, this disorder may be due to dysfunction in frontal neural systems that support voluntary regulation of emotion.

Behaviour, physiology and experience of pathological laughing and crying in amyotrophic lateral sclerosis

PubMed Central

Olney, Nicholas T.; Goodkind, Madeleine S.; Lomen-Hoerth, Catherine; Whalen, Patrick K.; Williamson, Craig A.; Holley, Deborah E.; Verstaen, Alice; Brown, Laurel M.; Miller, Bruce L.; Kornak, John; Levenson, Robert W.

2011-01-01

Pathological laughing and crying is a disorder of emotional expression seen in a number of neurological diseases. The aetiology is poorly understood, but clinical descriptions suggest a disorder of emotion regulation. The goals of this study were: (i) to characterize the subjective, behavioural and physiological emotional reactions that occur during episodes of pathological laughing and crying; (ii) to compare responses during these episodes to those that occur when emotions are elicited under standard conditions (watching sad and amusing emotional films, being startled); and (iii) to examine the ability of patients with this disorder to regulate their emotions under standardized conditions. Twenty-one patients with pathological laughing and crying due to amyotrophic lateral sclerosis and 14 with amyotrophic lateral sclerosis but no pathological laughing and crying were studied. Emotional measures included self-reported emotional experience, video recordings of facial reactivity and peripheral physiological responses (skin conductance, heart rate and somatic activity). Nineteen of the 21 patients with histories of pathological laughing and crying had at least one episode in the laboratory that they agreed constituted pathological laughing or crying (a total of 56 episodes were documented). Compared with viewing sad and amusing films, the episodes were associated with greater facial and physiological activation. Contrary to many clinical descriptions, episodes were often induced by contextually appropriate stimuli and associated with strong experiences of emotion that were consistent with the display. When instructed to regulate their facial responses to emotion-eliciting films, patients with pathological laughing and crying showed impairments compared with patients who did not have a history of this disorder. These findings support the idea that pathological laughing and crying represents activation of all channels of emotional responding (i.e. behavioural, physiological and subjective). Furthermore, they support previously advanced theories that, rather than being associated with general emotional hyperreactivity, this disorder may be due to dysfunction in frontal neural systems that support voluntary regulation of emotion. PMID:22155983

Failure of physiologic transformation of spiral arteries, endothelial and trophoblast cell activation, and acute atherosis in the basal plate of the placenta

PubMed Central

Labarrere, Carlos A.; DiCarlo, Hector L.; Bammerlin, Elaine; Hardin, James W.; Kim, Yeon Mee; Chaemsaithong, Piya; Haas, David M.; Kassab, Ghassan S.; Romero, Roberto

2018-01-01

Background Failure of physiologic transformation of spiral arteries has been reported in preeclampsia, fetal growth restriction, fetal death, and spontaneous preterm labor with intact or ruptured membranes. Spiral arteries with failure of physiologic transformation are prone to develop atherosclerotic-like lesions of atherosis. There are striking parallels between preeclampsia and atherosclerotic disease, and between lesions of atherosis and atherosclerosis. Endothelial activation, identified by intercellular adhesion molecule-1 expression, is present in atherosclerotic-like lesions of heart transplantation and considered a manifestation of rejection. Similarly, endothelial activation/dysfunction has been implicated in the pathophysiology of atherosclerosis and preeclampsia. Intercellular adhesion molecule-1-overexpressing-activated endothelial cells are more resistant to trophoblast displacement than nonactivated endothelium and may contribute to shallow spiral artery trophoblastic invasion in obstetrical syndromes having failure of physiologic transformation. Objective To determine whether failure of spiral artery physiologic transformation was associated with activation of interstitial extravillous trophoblasts and/or spiral artery endothelium and presence of acute atherosis in the placental basal plate. Study Design A cross-sectional study of 123 placentas (19-42 weeks’ gestation) obtained from normal pregnancies (n = 22), preterm prelabor rupture of membranes (n = 26), preterm labor (n = 23), preeclampsia (n = 27), intrauterine fetal death (n = 15), and small for gestational age (n = 10) was performed. Failure of spiral artery physiologic transformation and presence of cell activation was determined using immunohistochemistry of placental basal plates containing a median of 4 (minimum: 1; maximum: 9) vessels per placenta. Endothelial/trophoblast cell activation was defined by the expression of intercellular adhesion molecule-1 (ICAM-1). Investigators examining microscopic sections were blinded to clinical diagnosis. Pairwise comparisons among placenta groups were performed with the Fisher’s exact and Wilcoxon rank sum tests using a Bonferroni-adjusted level of significance (.025). Results 87% (94/108) of placentas having spiral arteries with failure of physiologic transformation (actin-positive and cytokeratin-negative) in the basal plate, and 0% (0/15) of placentas having only spiral arteries with complete physiologic transformation (cytokeratin-positive and actin-negative), had arterial endothelial and/or interstitial extravillous trophoblasts reactive with the ICAM-1 activation marker (P < .001). A significant correlation (R2 = 0.84) was found between expression of spiral artery endothelial and interstitial extravillous trophoblast ICAM-1 (P < .001) in activated placentas. Lesions of atherosis were found in 31.9% (30/94) of placentas with complete and/or partial failure of physiologic transformation of spiral arteries that were ICAM-1-positive, in none of the 14 placentas with failure of physiologic transformation that were ICAM-1-negative, and in none of the 15 placentas with complete spiral artery physiologic transformation without failure (P = .001). All placentas (30/30, 100%) with atherosis were identified in placentas having concomitant spiral artery endothelial and interstitial extravillous trophoblast activation. Conclusion Failure of spiral artery physiologic transformation in the placental basal plate is associated with interstitial extravillous trophoblast and arterial endothelial activation along with increased frequency of spiral artery atherosis. These findings may be used to improve the characterization of different disorders of the placental bed such as in refining the existing tools for the early prediction of risk for preterm, preeclamptic, and other abnormal pregnancies. PMID:28034657

Failure of physiologic transformation of spiral arteries, endothelial and trophoblast cell activation, and acute atherosis in the basal plate of the placenta.

PubMed

Labarrere, Carlos A; DiCarlo, Hector L; Bammerlin, Elaine; Hardin, James W; Kim, Yeon M; Chaemsaithong, Piya; Haas, David M; Kassab, Ghassan S; Romero, Roberto

2017-03-01

Failure of physiologic transformation of spiral arteries has been reported in preeclampsia, fetal growth restriction, fetal death, and spontaneous preterm labor with intact or ruptured membranes. Spiral arteries with failure of physiologic transformation are prone to develop atherosclerotic-like lesions of atherosis. There are striking parallels between preeclampsia and atherosclerotic disease, and between lesions of atherosis and atherosclerosis. Endothelial activation, identified by intercellular adhesion molecule-1 expression, is present in atherosclerotic-like lesions of heart transplantation, and is considered a manifestation of rejection. Similarly, endothelial activation/dysfunction has been implicated in the pathophysiology of atherosclerosis and preeclampsia. Intercellular adhesion molecule-1-overexpressing-activated endothelial cells are more resistant to trophoblast displacement than nonactivated endothelium, and may contribute to shallow spiral artery trophoblastic invasion in obstetrical syndromes having failure of physiologic transformation. We sought to determine whether failure of spiral artery physiologic transformation was associated with activation of interstitial extravillous trophoblasts and/or spiral artery endothelium and presence of acute atherosis in the placental basal plate. A cross-sectional study of 123 placentas (19-42 weeks' gestation) obtained from normal pregnancies (n = 22), preterm prelabor rupture of membranes (n = 26), preterm labor (n = 23), preeclampsia (n = 27), intrauterine fetal death (n = 15), and small for gestational age (n = 10) was performed. Failure of spiral artery physiologic transformation and presence of cell activation was determined using immunohistochemistry of placental basal plates containing a median of 4 (minimum: 1; maximum: 9) vessels per placenta. Endothelial/trophoblast cell activation was defined by the expression of intercellular adhesion molecule-1. Investigators examining microscopic sections were blinded to clinical diagnosis. Pairwise comparisons among placenta groups were performed with Fisher exact test and Wilcoxon rank sum test using a Bonferroni-adjusted level of significance (.025). We found that 87% (94/108) of placentas having spiral arteries with failure of physiologic transformation (actin-positive and cytokeratin-negative) in the basal plate, and 0% (0/15) of placentas having only spiral arteries with complete physiologic transformation (cytokeratin-positive and actin-negative), had arterial endothelial and/or interstitial extravillous trophoblasts reactive with the intercellular adhesion molecule-1 activation marker (P < .001). A significant correlation (R 2  = 0.84) was found between expression of spiral artery endothelial and interstitial extravillous trophoblast intercellular adhesion molecule-1 (P < .001) in activated placentas. Lesions of atherosis were found in 31.9% (30/94) of placentas with complete and/or partial failure of physiologic transformation of spiral arteries that were intercellular adhesion molecule-1-positive, in none of the 14 placentas with failure of physiologic transformation that were intercellular adhesion molecule-1-negative, and in none of the 15 placentas with complete spiral artery physiologic transformation without failure (P = .001). All placentas (30/30, 100%) with atherosis were identified in placentas having concomitant spiral artery endothelial and interstitial extravillous trophoblast activation. Failure of spiral artery physiologic transformation in the placental basal plate is associated with interstitial extravillous trophoblast and arterial endothelial activation along with increased frequency of spiral artery atherosis. These findings may be used to improve the characterization of different disorders of the placental bed such as in refining the existing tools for the early prediction of risk for preterm, preeclamptic, and other abnormal pregnancies. Copyright © 2016 Elsevier Inc. All rights reserved.

It's Difficult to Change the Way We Teach: Lessons from the Integrative Themes in Physiology Curriculum Module Project

ERIC Educational Resources Information Center

Silverthorn, Dee U.; Thorn, Patti M.; Svinicki, Marilla D.

2006-01-01

The Integrative Themes in Physiology (ITIP) project was a National Science Foundation-funded collaboration between the American Physiological Society (APS) and the Human Anatomy and Physiology Society (HAPS). The project goal was to create instructional resources that emphasized active learning in undergraduate anatomy and physiology classrooms.…

Abstracts of Review Articles and Educational Materials in Physiology

ERIC Educational Resources Information Center

Physiology Teacher, 1977

1977-01-01

Contained are 99 abstracts of review articles, texts, books, manuals, learning programs, and audiovisual material used in teaching physiology. Specific fields include cell physiology, circulation, comparative physiology, development and aging, endocrinology and metabolism, environmental and exercise physiology, gastrointestinal physiology, muscle…

Crew Factors in Flight Operations X: Alertness Management in Flight Operations

NASA Technical Reports Server (NTRS)

Rosekind, Mark R.; Gander, Philippa H.; Connell, Linda J.; Co, Elizabeth L.

1999-01-01

In response to a 1980 congressional request, NASA Ames Research Center initiated a Fatigue/Jet Lag Program to examine fatigue, sleep loss, and circadian disruption in aviation. Research has examined fatigue in a variety of flight environments using a range of measures (from self-report to performance to physiological). In 1991, the program evolved into the Fatigue Countermeasures Program, emphasizing the development and evaluation of strategies to maintain alertness and performance in operational settings. Over the years, the Federal Aviation Administration (FAA) has become a collaborative partner in support of fatigue research and other Program activities. From the inception of the Program, a principal goal was to return the information learned from research and other Program activities to the operational community. The objectives of this Education and Training Module are to explain what has been learned about the physiological mechanisms that underlie fatigue, demonstrate the application of this information in flight operations, and offer some specific fatigue counter-measure recommendations. It is intended for all segments of the aeronautics industry, including pilots, flight attendants, managers, schedulers, safety and policy personnel, maintenance crews, and others involved in an operational environment that challenges human physiological capabilities because of fatigue, sleep loss, and circadian disruption.

Multiple Regulatory Systems Coordinate DNA Replication with Cell Growth in Bacillus subtilis

PubMed Central

Murray, Heath; Koh, Alan

2014-01-01

In many bacteria the rate of DNA replication is linked with cellular physiology to ensure that genome duplication is coordinated with growth. Nutrient-mediated growth rate control of DNA replication initiation has been appreciated for decades, however the mechanism(s) that connects these cell cycle activities has eluded understanding. In order to help address this fundamental question we have investigated regulation of DNA replication in the model organism Bacillus subtilis. Contrary to the prevailing view we find that changes in DnaA protein level are not sufficient to account for nutrient-mediated growth rate control of DNA replication initiation, although this regulation does require both DnaA and the endogenous replication origin. We go on to report connections between DNA replication and several essential cellular activities required for rapid bacterial growth, including respiration, central carbon metabolism, fatty acid synthesis, phospholipid synthesis, and protein synthesis. Unexpectedly, the results indicate that multiple regulatory systems are involved in coordinating DNA replication with cell physiology, with some of the regulatory systems targeting oriC while others act in a oriC-independent manner. We propose that distinct regulatory systems are utilized to control DNA replication in response to diverse physiological and chemical changes. PMID:25340815

Multiple regulatory systems coordinate DNA replication with cell growth in Bacillus subtilis.

PubMed

Murray, Heath; Koh, Alan

2014-10-01

In many bacteria the rate of DNA replication is linked with cellular physiology to ensure that genome duplication is coordinated with growth. Nutrient-mediated growth rate control of DNA replication initiation has been appreciated for decades, however the mechanism(s) that connects these cell cycle activities has eluded understanding. In order to help address this fundamental question we have investigated regulation of DNA replication in the model organism Bacillus subtilis. Contrary to the prevailing view we find that changes in DnaA protein level are not sufficient to account for nutrient-mediated growth rate control of DNA replication initiation, although this regulation does require both DnaA and the endogenous replication origin. We go on to report connections between DNA replication and several essential cellular activities required for rapid bacterial growth, including respiration, central carbon metabolism, fatty acid synthesis, phospholipid synthesis, and protein synthesis. Unexpectedly, the results indicate that multiple regulatory systems are involved in coordinating DNA replication with cell physiology, with some of the regulatory systems targeting oriC while others act in a oriC-independent manner. We propose that distinct regulatory systems are utilized to control DNA replication in response to diverse physiological and chemical changes.

Resting state functional connectivity: its physiological basis and application in neuropharmacology.

PubMed

Lu, Hanbing; Stein, Elliot A

2014-09-01

Brain structures do not work in isolation; they work in concert to produce sensory perception, motivation and behavior. Systems-level network activity can be investigated by resting state magnetic resonance imaging (rsMRI), an emerging neuroimaging technique that assesses the synchrony of the brain's ongoing spontaneous activity. Converging evidence reveals that rsMRI is able to consistently identify distinct spatiotemporal patterns of large-scale brain networks. Dysregulation within and between these networks has been implicated in a number of neurodegenerative and neuropsychiatric disorders, including Alzheimer's disease and drug addiction. Despite wide application of this approach in systems neuroscience, the physiological basis of these fluctuations remains incompletely understood. Here we review physiological studies in electrical, metabolic and hemodynamic fluctuations that are most pertinent to the rsMRI signal. We also review recent applications to neuropharmacology - specifically drug effects on resting state fluctuations. We speculate that the mechanisms governing spontaneous fluctuations in regional oxygenation availability likely give rise to the observed rsMRI signal. We conclude by identifying several open questions surrounding this technique. This article is part of the Special Issue Section entitled 'Neuroimaging in Neuropharmacology'. Published by Elsevier Ltd.

Crew Factors in Flight Operations X: Alertness Management in Flight Operations

NASA Technical Reports Server (NTRS)

Rosekind, Mark R.; Gander, Philippa H.; Connell, Linda J.; Co, Elizabeth L.

2001-01-01

In response to a 1980 congressional request, NASA Ames Research Center initiated a Fatigue/Jet Lag Program to examine fatigue, sleep loss, and circadian disruption in aviation. Research has examined fatigue in a variety of flight environments using a range of measures (from self-report to performance to physiological). In 1991, the program evolved into the Fatigue Countermeasures Program, emphasizing the development and evaluation of strategies to maintain alertness and performance in operational settings. Over the years, the Federal Aviation Administration (FAA) has become a collaborative partner in support of fatigue research and other Program activities. From the inception of the Program, a principal goal was to return the information learned from research and other Program activities to the operational community. The objectives of this Education and Training Module are to explain what has been learned about the physiological mechanisms that underlie fatigue, demonstrate the application of this information in flight operations, and offer some specific fatigue countermeasure recommendations. It is intended for all segments of the aeronautics industry, including pilots, flight attendants, managers, schedulers, safety and policy personnel, maintenance crews, and others involved in an operational environment that challenges human physiological capabilities because of fatigue, sleep loss, and circadian disruption.

Stress, Workload and Physiology Demand During Extravehicular Activity: A Pilot Study

PubMed Central

Rai, Balwant; Kaur, Jasdeep; Foing, Bernard H

2012-01-01

Background: Extravehicular activity (EVA), such as exercise performed under unique environmental conditions, is essential for supporting daily living in weightlessness and for further space exploration like long Mars mission. Aim: The study was planned stress, workload, and physiological demands of simulated Mars exploration. Materials and Methods: In this study, the six-person crew lived (24 hours) for 14 days during a short-term stay at the Mars Desert Research Station. The heart rates, salivary cortisol, workload, peak oxygen uptake or maximal aerobic capacity of the crew are measured before, during and after an EVA. Results: Data for heart rate showed the same trend as peak oxygen uptake or maximal aerobic capacity, with a maximal increase to 85% of peak. The rating of subscale showed a significant increase in EVA as compared to run. Salivary cortisol levels and heart rates were increased in both groups, although significant increased of cortisol levels and heart rates more in EVA as compared to hill running crew members. Conclusion: Further study is required on large scale taken into account of limitations of this study and including other physiological and psychological parameters in Mars analog environment. PMID:22754877

Thermoregulatory performance and habitat selection of the eastern box turtle (Terrapene carolina carolina)

PubMed Central

Parlin, Adam F; do Amaral, José Pedro S; Dougherty, John Kelly; Stevens, M Henry H

2017-01-01

Abstract Environmental conditions may affect individual physiological processes that influence short-term performance and ultimately growth, survival and reproduction. As such, habitats selected by animals must provide suitable and adequate resources. Ectothermic species are highly dependent on climatic conditions and ambient temperatures that dictate body temperature regulation and in turn physiological processes. We investigated the thermoregulatory performance, habitat selection, and movements of an ectothermic vertebrate, the Eastern box turtle (Terrapene carolina carolina) to assess the importance of thermoregulatory physiology in habitat selection. We evaluated the relationship between habitat selection and thermoregulatory performance in Southwest Ohio over two active seasons from May until October. We found that T. carolina selected shaded habitats, including evergreen and deciduous forests, as well as herbaceous grasslands, conformed to the ambient temperatures throughout the active season, although these habitats had temperatures below those expected based on thermal optima of box turtles. Further, we found that movement was not correlated with internal body temperature. Our study shows that thermal conditions are not paramount in habitat selection of box turtles, but that cooler temperatures do not have an effect on the extent of their locomotion. PMID:29255608

Physiological Linkage in Couples and its Implications for Individual and Interpersonal Functioning: A Literature Review

PubMed Central

Timmons, Adela C.; Margolin, Gayla; Saxbe, Darby E.

2015-01-01

Do partners’ levels of physiological arousal become linked in close relationships? The term “physiological linkage” describes covariation between people in their moment-to-moment physiological states. The current review presents a conceptual framework to guide research on linkage in romantic relationships and discusses the potential implications of being “linked.” Evidence of linkage was found across a broad range of physiological indices and in a variety of contexts, including during laboratory-based conflict and in daily life. Four hypotheses regarding how linkage relates to individual and interpersonal functioning are evaluated: (1) co-activation of the sympathetic nervous system or hypothalamic-pituitary adrenal axis is “bad,” (2) moderate physiological linkage is “just right,” (3) physiological linkage is problematic if the individual or couple is overloaded, and (4) the implications of physiological linkage depend on the emotional context. We found partial support for the first hypothesis and determined that more research is needed to evaluate the remaining hypotheses. Linkage in cortisol was negatively associated with relationship satisfaction; but at the same time, linkage in multiple systems was positively associated with indices of relationship connectedness, such as the amount of time spent together and the ability to identify the emotions of one’s partner. These results suggest that linkage may confer benefits but also may put couples at risk if they become entrenched in patterns of conflict or stress. With research in this area burgeoning in recent years, this review indicates that linkage is a promising construct with applications for interventions targeting individual health and couple functioning. PMID:26147932

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.

RNA-Seq Reveals an Integrated Immune Response in Nucleated Erythrocytes

PubMed Central

Morera, Davinia; Roher, Nerea; Ribas, Laia; Balasch, Joan Carles; Doñate, Carmen; Callol, Agnes; Boltaña, Sebastian; Roberts, Steven; Goetz, Giles; Goetz, Frederick W.; MacKenzie, Simon A.

2011-01-01

Background Throughout the primary literature and within textbooks, the erythrocyte has been tacitly accepted to have maintained a unique physiological role; namely gas transport and exchange. In non-mammalian vertebrates, nucleated erythrocytes are present in circulation throughout the life cycle and a fragmented series of observations in mammals support a potential role in non-respiratory biological processes. We hypothesised that nucleated erythrocytes could actively participate via ligand-induced transcriptional re-programming in the immune response. Methodology/Principal Findings Nucleated erythrocytes from both fish and birds express and regulate specific pattern recognition receptor (PRR) mRNAs and, thus, are capable of specific pathogen associated molecular pattern (PAMP) detection that is central to the innate immune response. In vitro challenge with diverse PAMPs led to de novo specific mRNA synthesis of both receptors and response factors including interferon-alpha (IFNα) that exhibit a stimulus-specific polysomal shift supporting active translation. RNA-Seq analysis of the PAMP (Poly (I∶C), polyinosinic∶polycytidylic acid)-erythrocyte response uncovered diverse cohorts of differentially expressed mRNA transcripts related to multiple physiological systems including the endocrine, reproductive and immune. Moreover, erythrocyte-derived conditioned mediums induced a type-1 interferon response in macrophages thus supporting an integrative role for the erythrocytes in the immune response. Conclusions/Significance We demonstrate that nucleated erythrocytes in non-mammalian vertebrates spanning significant phylogenetic distance participate in the immune response. RNA-Seq studies highlight a mRNA repertoire that suggests a previously unrecognized integrative role for the erythrocytes in other physiological systems. PMID:22046430

The Structural Basis of IKs Ion-Channel Activation: Mechanistic Insights from Molecular Simulations.

PubMed

Ramasubramanian, Smiruthi; Rudy, Yoram

2018-06-05

Relating ion channel (iCh) structural dynamics to physiological function remains a challenge. Current experimental and computational techniques have limited ability to explore this relationship in atomistic detail over physiological timescales. A framework associating iCh structure to function is necessary for elucidating normal and disease mechanisms. We formulated a modeling schema that overcomes the limitations of current methods through applications of artificial intelligence machine learning. Using this approach, we studied molecular processes that underlie human IKs voltage-mediated gating. IKs malfunction underlies many debilitating and life-threatening diseases. Molecular components of IKs that underlie its electrophysiological function include KCNQ1 (a pore-forming tetramer) and KCNE1 (an auxiliary subunit). Simulations, using the IKs structure-function model, reproduced experimentally recorded saturation of gating-charge displacement at positive membrane voltages, two-step voltage sensor (VS) movement shown by fluorescence, iCh gating statistics, and current-voltage relationship. Mechanistic insights include the following: 1) pore energy profile determines iCh subconductance; 2) the entire protein structure, not limited to the pore, contributes to pore energy and channel subconductance; 3) interactions with KCNE1 result in two distinct VS movements, causing gating-charge saturation at positive membrane voltages and current activation delay; and 4) flexible coupling between VS and pore permits pore opening at lower VS positions, resulting in sequential gating. The new modeling approach is applicable to atomistic scale studies of other proteins on timescales of physiological function. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Role of Regulators of G Protein Signaling Proteins in Bone Physiology and Pathophysiology.

PubMed

Jules, Joel; Yang, Shuying; Chen, Wei; Li, Yi-Ping

2015-01-01

Regulators of G protein signaling (RGS) proteins enhance the intrinsic GTPase activity of α subunits of the heterotrimeric G protein complex of G protein-coupled receptors (GPCRs) and thereby inactivate signal transduction initiated by GPCRs. The RGS family consists of nearly 37 members with a conserved RGS homology domain which is critical for their GTPase accelerating activity. RGS proteins are expressed in most tissues, including heart, lung, brain, kidney, and bone and play essential roles in many physiological and pathological processes. In skeletal development and bone homeostasis as well as in many bone disorders, RGS proteins control the functions of various GPCRs, including the parathyroid hormone receptor type 1 and calcium-sensing receptor and also regulate various critical signaling pathways, such as Wnt and calcium oscillations. This chapter will discuss the current findings on the roles of RGS proteins in regulating signaling of key GPCRs in skeletal development and bone homeostasis. We also will examine the current updates of RGS proteins' regulation of calcium oscillations in bone physiology and highlight the roles of RGS proteins in selected bone pathological disorders. Despite the recent advances in bone and mineral research, RGS proteins remain understudied in the skeletal system. Further understanding of the roles of RGS proteins in bone should not only provide great insights into the molecular basis of various bone diseases but also generate great therapeutic drug targets for many bone diseases. © 2015 Elsevier Inc. All rights reserved.

[The role of endocannabinoid system in physiological and pathological processes in the eye].

PubMed

Nadolska, Krystyna; Goś, Roman

2008-01-01

Plant of Cannabis sativa/ marihuana except for its psychotropic effects possesses a range of pharmacological properties, that has been utilized for medical purposes over a period of millenia. Investigations concerning biochemical mechanism of action of the main and most active pharmacological compound of Cannabis sativa, cannabinoid 9-THC, contributed to the discovery of cannabinoid receptors both in the central nervous system (CNS) and peripheral tissues, that mediated actions of this substance. The discovery made possible identification of a new, endogenous signaling system reffered to as the endocannabinoid system. Besides cannabinoid receptors CB1 and CB2, the system includes it's endogenic ligands (endocannabinoids) and compounds that participate in their biosynthesis and inactivation. Structure and functioning of the endocannabinoid system is conservative in all vertebrates. It's activation with plant, synthetic and endogenous cannabinoids has an influence on multiple physiological and pathological processes within the eye.

Carbon dioxide-sensing in organisms and its implications for human disease

PubMed Central

Cummins, Eoin P.; Selfridge, Andrew C.; Sporn, Peter H.; Sznajder, Jacob I.; Taylor, Cormac T.

2013-01-01

The capacity of organisms to sense changes in the levels of internal and external gases and to respond accordingly is central to a range of physiologic and pathophysiologic processes. Carbon dioxide, a primary product of oxidative metabolism is one such gas that can be sensed by both prokaryotic and eukaryotic cells and in response to altered levels, elicit the activation of multiple adaptive pathways. The outcomes of activating CO2-sensitive pathways in various species include increased virulence of fungal and bacterial pathogens, prey-seeking behavior in insects as well as taste perception, lung function, and the control of immunity in mammals. In this review, we discuss what is known about the mechanisms underpinning CO2 sensing across a range of species and consider the implications of this for physiology, disease progression, and the possibility of developing new therapeutics for inflammatory and infectious disease. PMID:24045706

Nobiletin: a citrus flavonoid displaying potent physiological activity.

PubMed

Noguchi, Shuji; Atsumi, Haruka; Iwao, Yasunori; Kan, Toshiyuki; Itai, Shigeru

2016-02-01

Nobiletin [systematic name: 2-(3,4-dimethoxyphenyl)-5,6,7,8-tetramethoxy-4H-chromen-4-one; C21H22O8] is a flavonoid found in citrus peels, and has been reported to show a wide range of physiological properties, including anti-inflammatory, anticancer and antidementia activities. We have solved the crystal structure of nobiletin, which revealed that the chromene and arene rings of its flavone moiety, as well as the two methoxy groups bound to its arene ring, were coplanar. In contrast, the C atoms of the four methoxy groups bound to the chromene ring are out of the plane, making the molecule conformationally chiral. A comparison of the crystal structures of nobiletin revealed that it could adopt a variety of different conformations through rotation of the covalent bond between the chromene and arene rings, and the orientations of methoxy groups bound to the chromene ring.

Proteinase-Activated Receptor 2 May Drive Cancer Progression by Facilitating TGF-β Signaling.

PubMed

Ungefroren, Hendrik; Witte, David; Rauch, Bernhard H; Settmacher, Utz; Lehnert, Hendrik; Gieseler, Frank; Kaufmann, Roland

2017-11-22

The G protein-coupled receptor proteinase-activated receptor 2 (PAR2) has been implicated in various aspects of cellular physiology including inflammation, obesity and cancer. In cancer, it usually acts as a driver of cancer progression in various tumor types by promoting invasion and metastasis in response to activation by serine proteinases. Recently, we discovered another mode through which PAR2 may enhance tumorigenesis: crosstalk with transforming growth factor-β (TGF-β) signaling to promote TGF-β1-induced cell migration/invasion and invasion-associated gene expression in ductal pancreatic adenocarcinoma (PDAC) cells. In this chapter, we review what is known about the cellular TGF-β responses and signaling pathways affected by PAR2 expression, the signaling activities of PAR2 required for promoting TGF-β signaling, and the potential molecular mechanism(s) that underlie(s) the TGF-β signaling-promoting effect. Since PAR2 is activated through various serine proteinases and biased agonists, it may couple TGF-β signaling to a diverse range of other physiological processes that may or may not predispose cells to cancer development such as local inflammation, systemic coagulation and pathogen infection.

Proteinase-Activated Receptor 2 May Drive Cancer Progression by Facilitating TGF-β Signaling

PubMed Central

Ungefroren, Hendrik; Witte, David; Settmacher, Utz; Lehnert, Hendrik; Kaufmann, Roland

2017-01-01

The G protein-coupled receptor proteinase-activated receptor 2 (PAR2) has been implicated in various aspects of cellular physiology including inflammation, obesity and cancer. In cancer, it usually acts as a driver of cancer progression in various tumor types by promoting invasion and metastasis in response to activation by serine proteinases. Recently, we discovered another mode through which PAR2 may enhance tumorigenesis: crosstalk with transforming growth factor-β (TGF-β) signaling to promote TGF-β1-induced cell migration/invasion and invasion-associated gene expression in ductal pancreatic adenocarcinoma (PDAC) cells. In this chapter, we review what is known about the cellular TGF-β responses and signaling pathways affected by PAR2 expression, the signaling activities of PAR2 required for promoting TGF-β signaling, and the potential molecular mechanism(s) that underlie(s) the TGF-β signaling–promoting effect. Since PAR2 is activated through various serine proteinases and biased agonists, it may couple TGF-β signaling to a diverse range of other physiological processes that may or may not predispose cells to cancer development such as local inflammation, systemic coagulation and pathogen infection. PMID:29165389

Physiological changes, sleep, and morning mood in an isolated environment

NASA Technical Reports Server (NTRS)

Kraft, Norbert O.; Inoue, Natsuhiko; Mizuno, Koh; Ohshima, Hiroshi; Murai, Tadashi; Sekiguchi, Chiharu; Orasanu, J. M. (Principal Investigator)

2002-01-01

BACKGROUND: Previous isolation studies have shown increased 24-h urine volumes and body weight gains in subjects. This project examined those and other physiological variables in relationship to sleep motor activity, subjective sleep quality, mood, and complaints during confinement. METHODS: Six male and two female subjects lived for 7 d in the National Space Development Agency of Japan's isolation chamber, which simulates the interior of the Japanese Experiment Module. Each 24-h period included 6 h of sleep, 3 meals, and 20 min of exercise. Each morning, subjects completed Sleep Sensation and Complaint Index questionnaires. Catecholamine and creatinine excretion, urine volume, and body weight were measured on the 2 d before and 2 d after confinement, and sleep motor activity was measured during confinement. RESULTS: Confinement produced no significant change in body weight, urine volume, or questionnaire results. In contrast, epinephrine, norepinephrine, and sleep motor activity exhibited significant differences during confinement (p < 0.05). Higher nocturnal norepinephrine excretion correlated with higher sleep motor activity. CONCLUSION: The 24-h epinephrine values were slightly higher than normal throughout the experiment, but lower than for subjects working under time-stress. High sympathetic activity (as indicated by norepinephrine) may have interfered with sleep.

Matrix metalloproteinases: their biological functions and clinical implications.

PubMed

Hijova, E

2005-01-01

Matrix metalloproteinases (MMPs), which are also known as matrixins, are proteinases that participate in extracellular matrix remodelling and degradation. Under normal physiological conditions, the activities of MMPs are precisely regulated at the level of transcription, at that of activation of the pro-MMP precursor zymogenes as well as at that of inhibition by endogenous inhibitors (tissue inhibitors of metalloproteinases, TIMPs). Alterations in the regulation of MMP activity are implicated in diseases such as cancer, fibrosis, arthritis and atherosclerosis. The pathological effects of MMPs and TIMPs in cardiovascular diseases involve vascular remodelling, atherosclerotic plaque instability and cardiac remodelling in congestive heart failure or after myocardial infarction. Since excessive tissue remodelling and increased matrix metalloproteinases activity have been demonstrated during atherosclerotic lesion progression (including plaque disruption), MMPs represent a potential target for therapeutic intervention aimed at the modification of vascular pathology by restoring the physiological balance between MMPs and TIMPs. Recent findings suggest that MMPs are also involved in cancer initiation, invasion and metastasis; MMP inhibitors could be considered for evaluation as cancer chemopreventive molecules. This review describes the members of MMP and TIMP families and discusses the structure, function and regulation of MMP activity. (Tab. 1, Ref: 45.)

Males and females show differential brain activation to taste when hungry and sated in gustatory and reward areas

PubMed Central

Haase, Lori; Green, Erin; Murphy, Claire

2011-01-01

Although males and females differ in eating behavior and prevalence rates for eating disorders and obesity, little is known about gender differences in cortical activation to pleasant and unpleasant pure tastes during the physiological states of hunger and satiety. Twenty-one healthy young adults (12 females and 9 males) underwent two functional magnetic resonance imaging scans. Using four pure tastants of differing qualities (i.e., salty, sour, bitter, sweet), the present study examined gender differences in fMRI activation during two motivational states (hunger and satiety). There was greater change in fMRI activation from hunger to satiety in males than females in response to all tastes within the middle frontal gyrus (BA 10), insula, and cerebellum. Males also had greater change in activation from hunger to satiety, relative to females, in limbic regions including dorsal striatum, amygdala, parahippocampal gyrus, and posterior and anterior cingulate; however, activation was stimulus dependent, despite equivalent ratings in perceived pleasantness and intensity. Interestingly, males and females showed significant change from hunger to satiety in response to citric acid, suggesting that in addition to gender and physiological condition, stimulus quality is an important factor in taste fMRI activation. These gender differences may have implications for the pathophysiology of eating disorders and obesity. PMID:21718731

A significant increase in both basal and maximal calcineurin activity following fluid percussion injury in the rat.

PubMed

Kurz, Jonathan E; Parsons, J Travis; Rana, Aniruddha; Gibson, Cynthia J; Hamm, Robert J; Churn, Severn B

2005-04-01

Calcineurin, a neuronally enriched, calcium-stimulated phosphatase, is an important modulator of many neuronal processes, including several that are physiologically related to the pathology of traumatic brain injury. This study examined the effects of moderate, central fluid percussion injury on the activity of this important neuronal enzyme. Animals were sacrificed at several time-points postinjury and cortical, hippocampal, and cerebellar homogenates were assayed for calcineurin activity by dephosphorylation of p-nitrophenol phosphate. A significant brain injury-dependent increase was observed in both hippocampal and cortical homogenates under both basal and maximally-stimulated reaction conditions. This increase persisted 2-3 weeks post-injury. Brain injury did not alter substrate affinity, but did induce a significant increase in the apparent maximal dephosphorylation rate. Unlike the other brain regions, no change in calcineurin activity was observed in the cerebellum following brain injury. No brain region tested displayed a significant change in calcineurin enzyme levels as determined by Western blot, demonstrating that increased enzyme synthesis was not responsible for the observed increase in activity. The data support the conclusion that fluid percussion injury results in increased calcineurin activity in the rat forebrain. This increased activity has broad physiological implications, possibly resulting in altered cellular excitability or a greater likelihood of neuronal cell death.

Concerted Changes in Gene Expression and Cell Physiology of the Cyanobacterium Synechocystis sp. Strain PCC 6803 during Transitions between Nitrogen and Light-Limited Growth1[W][OA

PubMed Central

Aguirre von Wobeser, Eneas; Ibelings, Bas W.; Bok, Jasper; Krasikov, Vladimir; Huisman, Jef; Matthijs, Hans C.P.

2011-01-01

Physiological adaptation and genome-wide expression profiles of the cyanobacterium Synechocystis sp. strain PCC 6803 in response to gradual transitions between nitrogen-limited and light-limited growth conditions were measured in continuous cultures. Transitions induced changes in pigment composition, light absorption coefficient, photosynthetic electron transport, and specific growth rate. Physiological changes were accompanied by reproducible changes in the expression of several hundred open reading frames, genes with functions in photosynthesis and respiration, carbon and nitrogen assimilation, protein synthesis, phosphorus metabolism, and overall regulation of cell function and proliferation. Cluster analysis of the nearly 1,600 regulated open reading frames identified eight clusters, each showing a different temporal response during the transitions. Two large clusters mirrored each other. One cluster included genes involved in photosynthesis, which were up-regulated during light-limited growth but down-regulated during nitrogen-limited growth. Conversely, genes in the other cluster were down-regulated during light-limited growth but up-regulated during nitrogen-limited growth; this cluster included several genes involved in nitrogen uptake and assimilation. These results demonstrate complementary regulation of gene expression for two major metabolic activities of cyanobacteria. Comparison with batch-culture experiments revealed interesting differences in gene expression between batch and continuous culture and illustrates that continuous-culture experiments can pick up subtle changes in cell physiology and gene expression. PMID:21205618

Physiological monitoring and analysis of a manned stratospheric balloon test program.

PubMed

Garbino, Alejandro; Blue, Rebecca S; Pattarini, James M; Law, Jennifer; Clark, Jonathan B

2014-02-01

The Red Bull Stratos Project consisted of incremental high altitude parachute jumps [maximum altitude 127,852 ft (38,969 m)] from a pressurized capsule suspended from a stratospheric helium-filled balloon. A physiological monitoring system was worn by the parachutist to provide operational medical and acceleration data and to record a unique set of data in a supersonic environment. Various physiological parameters, including heart rate (HR), respiratory rate (RR), skin temperature, and triaxial acceleration, were collected during the ascent, high altitude float, free fall, and parachute opening and descent stages of multiple low- and high altitude jumps. Physiologic data were synchronized with global positioning system (GPS) and audiovisual data for a comprehensive understanding of the environmental stressors experienced. HR reached maximum during capsule egress and remained elevated throughout free fall and landing. RR reached its maximum during free fall. Temperature data were unreliable and did not provide useful results. The highest accelerations parameters were recorded during parachute opening and during landing. During each high altitude jump, immediately after capsule egress, the parachutist experienced a few seconds of microgravity during which some instability occurred. Control was regained as the parachutist entered denser atmosphere. The high altitude environment resulted in extremely high vertical speeds due to little air resistance in comparison to lower altitude jumps with similar equipment. The risk for tumbling was highest at initial step-off. Physiological responses included elevated HR and RR throughout critical phases of free fall. The monitoring unit performed well despite the austere environment and extreme human performance activities.

GPER modulators: Opportunity Nox on the heels of a class Akt.

PubMed

Prossnitz, Eric R

2018-02-01

The (patho)physiology of estrogen and its receptors is complex. It is therefore not surprising that therapeutic approaches targeting this hormone include stimulation of its activity through supplementation with either the hormone itself or natural or synthetic agonists, inhibition of its activity through the use of antagonists or inhibitors of its synthesis, and tissue-selective modulation of its activity with biased ligands. The physiology of this hormone is further complicated by the existence of at least three receptors, the classical nuclear estrogen receptors α and β (ERα and ERβ), and the 7-transmembrane G protein-coupled estrogen receptor (GPER/GPR30), with overlapping but distinct pharmacologic profiles, particularly of anti-estrogenic ligands. GPER-selective ligands, as well as GPER knockout mice, have greatly aided our understanding of the physiological roles of GPER. Such ligands have revealed that GPER activation mediates many of the rapid cellular signaling events (including Ca 2+ mobilization, ERK and PI3K/Akt activation) associated with estrogen activity, as opposed to the nuclear ERs that are traditionally described to function as ligand-induced transcriptional factors. Many of the salutary effects of estrogen throughout the body are reproduced by the GPER-selective agonist G-1, which, owing to its minimal effects on reproductive tissues, can be considered a non-feminizing estrogenic compound, and thus of potential therapeutic use in both women and men. On the contrary, until recently GPER-selective antagonists had predominantly found preclinical application in cancer models where estrogen stimulates cell growth and survival. This viewpoint changed recently with the discovery that GPER is associated with aging, particularly that of the cardiovascular system, where the GPER antagonist G36 reduced hypertension and GPER deficiency prevented cardiac fibrosis and vascular dysfunction with age, through the downregulation of Nox1 and as a consequence superoxide production. Thus, similar to the classical ERs, both agonists and antagonists of GPER may be of therapeutic benefit depending on the disease or condition to be treated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Roles of the Sodium-Translocating NADH:Quinone Oxidoreductase (Na+-NQR) on Vibrio cholerae Metabolism, Motility and Osmotic Stress Resistance

PubMed Central

Minato, Yusuke; Halang, Petra; Quinn, Matthew J.; Faulkner, Wyatt J.; Aagesen, Alisha M.; Steuber, Julia; Stevens, Jan F.; Häse, Claudia C.

2014-01-01

The Na+ translocating NADH:quinone oxidoreductase (Na+-NQR) is a unique respiratory enzyme catalyzing the electron transfer from NADH to quinone coupled with the translocation of sodium ions across the membrane. Typically, Vibrio spp., including Vibrio cholerae, have this enzyme but lack the proton-pumping NADH:ubiquinone oxidoreductase (Complex I). Thus, Na+-NQR should significantly contribute to multiple aspects of V. cholerae physiology; however, no detailed characterization of this aspect has been reported so far. In this study, we broadly investigated the effects of loss of Na+-NQR on V. cholerae physiology by using Phenotype Microarray (Biolog), transcriptome and metabolomics analyses. We found that the V. cholerae ΔnqrA-F mutant showed multiple defects in metabolism detected by Phenotype Microarray. Transcriptome analysis revealed that the V. cholerae ΔnqrA-F mutant up-regulates 31 genes and down-regulates 55 genes in both early and mid-growth phases. The most up-regulated genes included the cadA and cadB genes, encoding a lysine decarboxylase and a lysine/cadaverine antiporter, respectively. Increased CadAB activity was further suggested by the metabolomics analysis. The down-regulated genes include sialic acid catabolism genes. Metabolomic analysis also suggested increased reductive pathway of TCA cycle and decreased purine metabolism in the V. cholerae ΔnqrA-F mutant. Lack of Na+-NQR did not affect any of the Na+ pumping-related phenotypes of V. cholerae suggesting that other secondary Na+ pump(s) can compensate for Na+ pumping activity of Na+-NQR. Overall, our study provides important insights into the contribution of Na+-NQR to V. cholerae physiology. PMID:24811312

Use of Case-Based or Hands-On Laboratory Exercises with Physiology Lectures Improves Knowledge Retention, but Veterinary Medicine Students Prefer Case-Based Activities

ERIC Educational Resources Information Center

McFee, Renee M.; Cupp, Andrea S.; Wood, Jennifer R.

2018-01-01

Didactic lectures are prevalent in physiology courses within veterinary medicine programs, but more active learning methods have also been utilized. Our goal was to identify the most appropriate learning method to augment the lecture component of our physiology course. We hypothesized that case-based learning would be well received by students and…

Gap Junctions

PubMed Central

Nielsen, Morten Schak; Axelsen, Lene Nygaard; Sorgen, Paul L.; Verma, Vandana; Delmar, Mario; Holstein-Rathlou, Niels-Henrik

2013-01-01

Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease. © 2012 American Physiological Society. Compr Physiol 2:1981-2035, 2012. PMID:23723031

Conformational properties of serine proteinase inhibitors (serpins) confer multiple pathophysiological roles.

PubMed

Janciauskiene, S

2001-03-26

Serine proteinase inhibitors (Serpins) are irreversible suicide inhibitors of proteases that regulate diverse physiological processes such as coagulation, fibrinolysis, complement activation, angiogenesis, apoptosis, inflammation, neoplasia and viral pathogenesis. The molecular structure and physical properties of serpins permit these proteins to adopt a number of variant conformations under physiological conditions including the native inhibitory form and several inactive, non-inhibitory forms, such as complexes with protease or other ligands, cleaved, polymerised and oxidised. Alterations of a serpin which affect its structure and/or secretion and thus reduce its functional levels may result in pathology. Serpin dysfunction has been implicated in thrombosis, emphysema, liver cirrhosis, immune hypersensitivity and mental disorders. The loss of inhibitory activity of serpins necessarily results in an imbalance between proteases and their inhibitors, but it may also have other physiological effects through the generation of abnormal concentrations of modified, non-inhibitory forms of serpins. Although these forms of inhibitory serpins are detected in tissues and fluids recovered from inflammatory sites, the important questions of which conditions result in generation of different molecular forms of serpins, what biological function these forms have, and which of them are directly linked to pathologies and/or may be useful markers for characterisation of disease states, remain to be answered. Elucidation of the biological activities of non-inhibitory forms of serpins may provide useful insights into the pathogenesis of diseases and suggest new therapeutic strategies.

Regulation of circadian blood pressure: from mice to astronauts.

PubMed

Agarwal, Rajiv

2010-01-01

Circadian variation is commonly seen in healthy people; aberration in these biological rhythms is an early sign of disease. Impaired circadian variation of blood pressure (BP) has been shown to be associated with greater target organ damage and with an elevated risk of cardiovascular events independent of the BP load. The purpose of this review is to examine the physiology of circadian BP variation and propose a tripartite model that explains the regulation of circadian BP. The time-keeper in mammals resides centrally in the suprachiasmatic nucleus. Apart from this central clock, molecular clocks exist in most peripheral tissues including vascular tissue and the kidney. These molecular clocks regulate sodium balance, sympathetic function and vascular tone. A physiological model is proposed that integrates our understanding of molecular clocks in mice with the circadian BP variation among humans. The master regulator in this proposed model is the sleep-activity cycle. The equivalents of peripheral clocks are endothelial and adrenergic functions. Thus, in the proposed model, the variation in circadian BP is dependent upon three major factors: physical activity, autonomic function, and sodium sensitivity. The integrated consideration of physical activity, autonomic function, and sodium sensitivity appears to explain the physiology of circadian BP variation and the pathophysiology of disrupted BP rhythms in various conditions and disease states. Our understanding of molecular clocks in mice may help to explain the provenance of blunted circadian BP variation even among astronauts.

Position of the American Dietetic Association: Functional foods.

PubMed

Hasler, Clare M; Bloch, Abby S; Thomson, Cynthia A; Enrione, Evelyn; Manning, Carolyn

2004-05-01

It is the position of the American Dietetic Association that functional foods, including whole foods and fortified, enriched, or enhanced foods, have a potentially beneficial effect on health when consumed as part of a varied diet on a regular basis, at effective levels. The Association supports research to define further the health benefits and risks of individual functional foods and their physiologically active components. Dietetics professionals will continue to work with the food industry, the government, the scientific community, and the media to ensure that the public has accurate information regarding this emerging area of food and nutrition science. Knowledge of the role of physiologically active food components, from both phytochemicals and zoochemicals, has changed the role of diet in health. Functional foods have evolved as food and nutrition science has advanced beyond the treatment of deficiency syndromes to reduction of disease risk. This position reviews the definition of functional foods, their regulation, and the scientific evidence supporting this emerging area of food and nutrition. Foods can no longer be evaluated only in terms of macronutrient and micronutrient content alone. Analyzing the content of other physiologically active components and evaluating their role in health promotion will be necessary. The availability of health-promoting functional foods in the US diet has the potential to help ensure a healthier population. However, each functional food should be evaluated on the basis of scientific evidence to ensure appropriate integration into a varied diet.

Anti-Angiogenic Action of Neutral Endopeptidase

DTIC Science & Technology

2005-11-30

side of hydrophobic amino acids and inactivates a variety of physiologically active peptides, including atrial natriuretic factor, substance P ...follows. 15. SUBJECT TERMS Angiogenesis, Cell surface peptidase , Neutral endopeptidase, Basic fibroblast growth factor, Prostate cancer Proteolysis 16...patients with prostate cancer. Cell-surface peptidases are the guardians of the cell against small stimulatory peptides, functioning to control growth

Acute intraperitoneal lipopolysaccharide influences the immune system in the absence of gut dysbiosis.

PubMed

Sylvia, Kristyn E; Demas, Gregory E

2018-03-01

There is bidirectional communication between the immune system and the gut microbiome, however the precise mechanisms regulating this crosstalk are not well understood. Microbial-associated molecular patterns (MAMPs) within the gut, including lipopolysaccharide (LPS) that produces a quick and robust activation of the immune system, may be one way by which these interactions occur. Endogenous levels of LPS in the gut are low enough that they do not usually cause disease, although, in times of increased LPS loads, they may be capable of increasing vulnerability of the gut to pathogenic bacteria. Furthermore, chronic, low-grade inflammation can have lasting effects on the gut, but the effects of acute inflammation on gut communities have not been thoroughly assessed. In this study, we first investigated whether a single modest dose of LPS administered to adult male and female Siberian hamsters (Phodopus sungorus) activated the immune system by measuring levels of circulating cortisol and the proinflammatory cytokine TNF-α in the liver compared with saline-treated animals. We then investigated whether this same acute dose of LPS altered the microbiome 48 h after treatment. We found that, although LPS increased cortisol and liver cytokine levels, and produced changes in food intake and body mass in both sexes, immunological changes were independent of gut dysbiosis 48 h after LPS injection. These data suggest that an acute immune activation may not be capable of altering the gut microbiome in healthy individuals. It is likely, however, that this type of immune challenge may have other physiological impacts on the gut's vulnerability, and future studies will investigate these relationships further. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Physiological and psychological effects of testosterone during severe energy deficit and recovery: A study protocol for a randomized, placebo-controlled trial for Optimizing Performance for Soldiers (OPS).

PubMed

Pasiakos, Stefan M; Berryman, Claire E; Karl, J Philip; Lieberman, Harris R; Orr, Jeb S; Margolis, Lee M; Caldwell, John A; Young, Andrew J; Montano, Monty A; Evans, William J; Vartanian, Oshin; Carmichael, Owen T; Gadde, Kishore M; Harris, Melissa; Rood, Jennifer C

2017-07-01

The physiological consequences of severe energy deficit include hypogonadism and the loss of fat-free mass. Prolonged energy deficit also impacts physical performance, mood, attentiveness, and decision-making capabilities. This study will determine whether maintaining a eugonadal state during severe, sustained energy deficit attenuates physiological decrements and maintains mental performance. This study will also assess the effects of normalizing testosterone levels during severe energy deficit and recovery on gut health and appetite regulation. Fifty physically active men will participate in a 3-phase, randomized, placebo-controlled study. After completing a 14-d, energy-adequate, diet acclimation phase (protein: 1.6g∙kg -1 ∙d -1 ; fat: 30% total energy intake), participants will be randomized to undergo a 28-d, 55% energy deficit phase with (DEF+TEST: 200mg testosterone enanthate per week) or without (DEF) exogenous testosterone. Diet and physical activity will be rigorously controlled. Recovery from the energy deficit (ad libitum diet, no testosterone) will be assessed until body mass has been recovered within ±2.5% of initial body mass. Body composition, stable isotope methodologies, proteomics, muscle biopsies, whole-room calorimetry, molecular biology, activity/sleep monitoring, personality and cognitive function assessments, functional MRI, and comprehensive biochemistries will be used to assess physiological and psychological responses to energy restriction and recovery feeding while volunteers are in an expected hypogonadal versus eugonadal state. The Optimizing Performance for Soldiers (OPS) study aims to determine whether preventing hypogonadism will mitigate declines in physical and mental function that typically occur during prolonged energy deficit, and the efficacy of testosterone replacement on recovery from severe underfeeding. NCT02734238. Copyright © 2017. Published by Elsevier Inc.

DRD2/CHRNA5 Interaction on Prefrontal Biology and Physiology during Working Memory

PubMed Central

Fazio, Leonardo; D'Ambrosio, Enrico; Gelao, Barbara; Tomasicchio, Aldo; Selvaggi, Pierluigi; Taurisano, Paolo; Quarto, Tiziana; Masellis, Rita; Rampino, Antonio; Caforio, Grazia; Popolizio, Teresa; Blasi, Giuseppe; Sadee, Wolfgang; Bertolino, Alessandro

2014-01-01

Background Prefrontal behavior and activity in humans are heritable. Studies in animals demonstrate an interaction between dopamine D2 receptors and nicotinic acetylcholine receptors on prefrontal behavior but evidence in humans is weak. Therefore, we hypothesize that genetic variation regulating dopamine D2 and nicotinic acetylcholine receptor signaling impact prefrontal cortex activity and related cognition. To test this hypothesis in humans, we explored the interaction between functional genetic variants in the D2 receptor gene (DRD2, rs1076560) and in the nicotinic receptor α5 gene (CHRNA5, rs16969968) on both dorsolateral prefrontal cortex mediated behavior and physiology during working memory and on prefrontal gray matter volume. Methods A large sample of healthy subjects was compared for genotypic differences for DRD2 rs1076560 (G>T) and CHNRA5 rs16969968 (G>A) on prefrontal phenotypes, including cognitive performance at the N-Back task, prefrontal physiology with BOLD fMRI during performance of the 2-Back working memory task, and prefrontal morphometry with structural MRI. Results We found that DRD2 rs1076560 and CHNRA5 rs16969968 interact to modulate cognitive function, prefrontal physiology during working memory, and prefrontal gray matter volume. More specifically, CHRNA5-AA/DRD2-GT subjects had greater behavioral performance, more efficient prefrontal cortex activity at 2Back working memory task, and greater prefrontal gray matter volume than the other genotype groups. Conclusions The present data extend previous studies in animals and enhance our understanding of dopamine and acetylcholine signaling in the human prefrontal cortex, demonstrating interactions elicited by working memory that are modulated by genetic variants in DRD2 and CHRNA5. PMID:24819610

DRD2/CHRNA5 interaction on prefrontal biology and physiology during working memory.

PubMed

Di Giorgio, Annabella; Smith, Ryan M; Fazio, Leonardo; D'Ambrosio, Enrico; Gelao, Barbara; Tomasicchio, Aldo; Selvaggi, Pierluigi; Taurisano, Paolo; Quarto, Tiziana; Masellis, Rita; Rampino, Antonio; Caforio, Grazia; Popolizio, Teresa; Blasi, Giuseppe; Sadee, Wolfgang; Bertolino, Alessandro

2014-01-01

Prefrontal behavior and activity in humans are heritable. Studies in animals demonstrate an interaction between dopamine D2 receptors and nicotinic acetylcholine receptors on prefrontal behavior but evidence in humans is weak. Therefore, we hypothesize that genetic variation regulating dopamine D2 and nicotinic acetylcholine receptor signaling impact prefrontal cortex activity and related cognition. To test this hypothesis in humans, we explored the interaction between functional genetic variants in the D2 receptor gene (DRD2, rs1076560) and in the nicotinic receptor α5 gene (CHRNA5, rs16969968) on both dorsolateral prefrontal cortex mediated behavior and physiology during working memory and on prefrontal gray matter volume. A large sample of healthy subjects was compared for genotypic differences for DRD2 rs1076560 (G>T) and CHNRA5 rs16969968 (G>A) on prefrontal phenotypes, including cognitive performance at the N-Back task, prefrontal physiology with BOLD fMRI during performance of the 2-Back working memory task, and prefrontal morphometry with structural MRI. We found that DRD2 rs1076560 and CHNRA5 rs16969968 interact to modulate cognitive function, prefrontal physiology during working memory, and prefrontal gray matter volume. More specifically, CHRNA5-AA/DRD2-GT subjects had greater behavioral performance, more efficient prefrontal cortex activity at 2Back working memory task, and greater prefrontal gray matter volume than the other genotype groups. The present data extend previous studies in animals and enhance our understanding of dopamine and acetylcholine signaling in the human prefrontal cortex, demonstrating interactions elicited by working memory that are modulated by genetic variants in DRD2 and CHRNA5.

Principal and independent component analysis of concomitant functional near infrared spectroscopy and magnetic resonance imaging data

NASA Astrophysics Data System (ADS)

Schelkanova, Irina; Toronov, Vladislav

2011-07-01

Although near infrared spectroscopy (NIRS) is now widely used both in emerging clinical techniques and in cognitive neuroscience, the development of the apparatuses and signal processing methods for these applications is still a hot research topic. The main unresolved problem in functional NIRS is the separation of functional signals from the contaminations by systemic and local physiological fluctuations. This problem was approached by using various signal processing methods, including blind signal separation techniques. In particular, principal component analysis (PCA) and independent component analysis (ICA) were applied to the data acquired at the same wavelength and at multiple sites on the human or animal heads during functional activation. These signal processing procedures resulted in a number of principal or independent components that could be attributed to functional activity but their physiological meaning remained unknown. On the other hand, the best physiological specificity is provided by broadband NIRS. Also, a comparison with functional magnetic resonance imaging (fMRI) allows determining the spatial origin of fNIRS signals. In this study we applied PCA and ICA to broadband NIRS data to distill the components correlating with the breath hold activation paradigm and compared them with the simultaneously acquired fMRI signals. Breath holding was used because it generates blood carbon dioxide (CO2) which increases the blood-oxygen-level-dependent (BOLD) signal as CO2 acts as a cerebral vasodilator. Vasodilation causes increased cerebral blood flow which washes deoxyhaemoglobin out of the cerebral capillary bed thus increasing both the cerebral blood volume and oxygenation. Although the original signals were quite diverse, we found very few different components which corresponded to fMRI signals at different locations in the brain and to different physiological chromophores.

Psychological Distress and Physiological Reactivity During In Vivo Exposure in People With Aviophobia.

PubMed

Busscher, Bert; Spinhoven, Philip; de Geus, Eco J C

2015-09-01

Exposure is regarded to be a crucial component of therapies for phobias. According to emotional processing theory, the success of exposure therapy is predicted by activation of subjective and physiological fear responses and their within-session habituation and between-session adaptation. This study tested this prediction for aviophobia. Seventy-nine participants following a highly standardized treatment program for aviophobia provided self-reported and physiological (heart rate, respiratory sinus arrhythmia and pre-ejection period) measurements of fear activation, within-session habituation, and between-session adaptation during exposure to flight-related stimuli, a flight simulator, and during two real flights. Multiple regression analyses were conducted to examine whether these measurements predicted therapy outcome up to 3 years after finishing therapy, including number of flights flown in this period. Both subjective and physiological arousal measurements indicated strong fear activation and large within-session habituation and between-session adaptation during exposure. Flight anxiety measures showed large improvements up to 3 years after treatment (η between 0.72 and 0.91). Lower self-reported anxiety during flight exposure was associated with lower flight anxiety after exposure (R = 0.15) and more flights flown (R = 0.14). Within-flight habituation or between-session adaptation of self-reported anxiety had no relationship with treatment outcome. Within-flight habituation of HR reactivity (R = 0.10) and respiratory sinus arrhythmia reactivity (R = 0.11) was associated with lower flight anxiety directly after the flight, but not on flight anxiety 3 years after finishing therapy or on long-term flying behavior. The results provide only weak support for emotional processing theory. Low self-reported anxiety during in vivo flight exposure was the best predictor of successful long-term therapy outcome.

Gender differences in physiologic markers and health behaviors associated with childhood obesity.

PubMed

Govindan, Morgen; Gurm, Roopa; Mohan, Sathish; Kline-Rogers, Eva; Corriveau, Nicole; Goldberg, Caren; Durussel-Weston, Jean; Eagle, Kim A; Jackson, Elizabeth A

2013-09-01

Previous studies have demonstrated gender-related differences in body composition, physical activity, and diet. This observational study assesses gender variance in independent predictors for obesity to determine targeted areas for intervention. Data from 1714 sixth-grade students enrolled in Project Healthy Schools were compared by using health behaviors and physiologic markers (lipids, random glucose, blood pressure, and resting and recovery heart rates). Students were stratified by gender and obesity (BMI ≥95th percentile by age and gender). Physiologic markers and behaviors were compared by using χ(2) analysis. Univariate associations with P < .10 were included in a stepwise logistic regression model to determine independent predictors for obesity by gender. Nonobese students (both boys and girls) showed significantly healthier physiologic parameters compared with their obese counterparts. Two behaviors independently correlated with obesity in both boys and girls: regularly eating school lunches (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.01-1.64; OR 1.27, 95% CI 1.00-1.62, respectively) and watching ≥2 hours of television per day (OR 1.19, 95% CI 1.07-1.32; OR 1.19, 95% CI 1.06-1.34, respectively). Vigorous physical activity and involvement in school sports teams appeared to be protective against obesity in boys (OR 0.90, 95% CI 0.82-0.98; OR 0.77, 95% CI 0.64-0.94, respectively), whereas milk consumption appeared protective in girls (OR 0.81, 95% CI 0.67-0.98). Among middle-school children, we observed gender-related differences in factors associated with obesity. Additional research is warranted to determine the beneficial impact of improving school lunches and decreasing screen time, while improving our understanding of gender-related differences in milk consumption and physical activities in relation to BMI.

The calcium-frequency response in the rat ventricular myocyte: an experimental and modelling study.

PubMed

Gattoni, Sara; Røe, Åsmund Treu; Frisk, Michael; Louch, William E; Niederer, Steven A; Smith, Nicolas P

2016-08-01

In the majority of species, including humans, increased heart rate increases cardiac contractility. This change is known as the force-frequency response (FFR). The majority of mammals have a positive force-frequency relationship (FFR). In rat the FFR is controversial. We derive a species- and temperature-specific data-driven model of the rat ventricular myocyte. As a measure of the FFR, we test the effects of changes in frequency and extracellular calcium on the calcium-frequency response (CFR) in our model and three altered models. The results show a biphasic peak calcium-frequency response, due to biphasic behaviour of the ryanodine receptor and the combined effect of the rapid calmodulin buffer and the frequency-dependent increase in diastolic calcium. Alterations to the model reveal that inclusion of Ca(2+) /calmodulin-dependent protein kinase II (CAMKII)-mediated L-type channel and transient outward K(+) current activity enhances the positive magnitude calcium-frequency response, and the absence of CAMKII-mediated increase in activity of the sarco/endoplasmic reticulum Ca(2+) -ATPase induces a negative magnitude calcium-frequency response. An increase in heart rate affects the strength of cardiac contraction by altering the Ca(2+) transient as a response to physiological demands. This is described by the force-frequency response (FFR), a change in developed force with pacing frequency. The majority of mammals, including humans, have a positive FFR, and cardiac contraction strength increases with heart rate. However, the rat and mouse are exceptions, with the majority of studies reporting a negative FFR, while others report either a biphasic or a positive FFR. Understanding the differences in the FFR between humans and rats is fundamental to interpreting rat-based experimental findings in the context of human physiology. We have developed a novel model of rat ventricular electrophysiology and calcium dynamics, derived predominantly from experimental data recorded under physiological conditions. As a measure of FFR, we tested the effects of changes in stimulation frequency and extracellular calcium concentration on the simulated Ca(2+) transient characteristics and showed a biphasic peak calcium-frequency relationship, consistent with recent observations of a shift from negative to positive FFR when approaching the rat physiological frequency range. We tested the hypotheses that (1) inhibition of Ca(2+) /calmodulin-dependent protein kinase II (CAMKII)-mediated increase in sarco/endoplasmic reticulum Ca(2+) -ATPase (SERCA) activity, (2) CAMKII modulation of SERCA, L-type channel and transient outward K(+) current activity and (3) Na(+) /K(+) pump dynamics play a significant role in the rat FFR. The results reveal a major role for CAMKII modulation of SERCA in the peak Ca(2+) -frequency response, driven most significantly by the cytosolic calcium buffering system and changes in diastolic Ca(2+) . © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Combinations of Physiologic Estrogens with Xenoestrogens Alter ERK Phosphorylation Profiles in Rat Pituitary Cells

PubMed Central

Jeng, Yow-Jiun; Watson, Cheryl S.

2011-01-01

Background Estrogens are potent nongenomic phospho-activators of extracellular-signal–regulated kinases (ERKs). A major concern about the toxicity of xenoestrogens (XEs) is potential alteration of responses to physiologic estrogens when XEs are present simultaneously. Objectives We examined estrogen-induced ERK activation, comparing the abilities of structurally related XEs (alkylphenols and bisphenol A) to alter ERK responses induced by physiologic concentrations (1 nM) of estradiol (E2), estrone (E1), and estriol (E3). Methods We quantified hormone/mimetic-induced ERK phosphorylations in the GH3/B6/F10 rat pituitary cell line using a plate immunoassay, comparing effects with those on cell proliferation and by estrogen receptor subtype-selective ligands. Results Alone, these structurally related XEs activate ERKs in an oscillating temporal pattern similar (but not identical) to that with physiologic estrogens. The potency of all estrogens was similar (active between femtomolar and nanomolar concentrations). XEs potently disrupted physiologic estrogen signaling at low, environmentally relevant concentrations. Generally, XEs potentiated (at the lowest, subpicomolar concentrations) and attenuated (at the highest, picomolar to 100 nM concentrations) the actions of the physiologic estrogens. Some XEs showed pronounced nonmonotonic responses/inhibitions. The phosphorylated ERK and proliferative responses to receptor-selective ligands were only partially correlated. Conclusions XEs are both imperfect potent estrogens and endocrine disruptors; the more efficacious an XE, the more it disrupts actions of physiologic estrogens. This ability to disrupt physiologic estrogen signaling suggests that XEs may disturb normal functioning at life stages where actions of particular estrogens are important (e.g., development, reproductive cycling, pregnancy, menopause). PMID:20870566

Physiological changes in neurodegeneration - mechanistic insights and clinical utility.

PubMed

Ahmed, Rebekah M; Ke, Yazi D; Vucic, Steve; Ittner, Lars M; Seeley, William; Hodges, John R; Piguet, Olivier; Halliday, Glenda; Kiernan, Matthew C

2018-05-01

The effects of neurodegenerative syndromes extend beyond cognitive function to involve key physiological processes, including eating and metabolism, autonomic nervous system function, sleep, and motor function. Changes in these physiological processes are present in several conditions, including frontotemporal dementia, amyotrophic lateral sclerosis, Alzheimer disease and the parkinsonian plus conditions. Key neural structures that mediate physiological changes across these conditions include neuroendocrine and hypothalamic pathways, reward pathways, motor systems and the autonomic nervous system. In this Review, we highlight the key changes in physiological processing in neurodegenerative syndromes and the similarities in these changes between different progressive neurodegenerative brain conditions. The changes and similarities between disorders might provide novel insights into the human neural correlates of physiological functioning. Given the evidence that physiological changes can arise early in the neurodegenerative process, these changes could provide biomarkers to aid in the early diagnosis of neurodegenerative diseases and in treatment trials.

Evidence for a curvilinear relationship between sympathetic nervous system activation and women's physiological sexual arousal.

PubMed

Lorenz, Tierney Ahrold; Harte, Christopher B; Hamilton, Lisa Dawn; Meston, Cindy M

2012-01-01

There is increasing evidence that women's physiological sexual arousal is facilitated by moderate sympathetic nervous system (SNS) activation. Literature also suggests that the level of SNS activation may play a role in the degree to which SNS activity affects sexual arousal. We provide the first empirical examination of a possible curvilinear relationship between SNS activity and women's genital arousal using a direct measure of SNS activation in 52 sexually functional women. The relationship between heart rate variability (HRV), a specific and sensitive marker of SNS activation, and vaginal pulse amplitude (VPA), a measure of genital arousal, was analyzed. Moderate increases in SNS activity were associated with higher genital arousal, while very low or very high SNS activation was associated with lower genital arousal. These findings imply that there is an optimal level of SNS activation for women's physiological sexual arousal. Copyright © 2011 Society for Psychophysiological Research.

Relations among pure-tone sound stimuli, neural activity, and the loudness sensation

NASA Technical Reports Server (NTRS)

Howes, W. L.

1972-01-01

Both the physiological and psychological responses to pure-tone sound stimuli are used to derive formulas which: (1) relate the loudness, loudness level, and sound-pressure level of pure tones; (2) apply continuously over most of the acoustic regime, including the loudness threshold; and (3) contain no undetermined coefficients. Some of the formulas are fundamental for calculating the loudness of any sound. Power-law formulas relating the pure-tone sound stimulus, neural activity, and loudness are derived from published data.

Modulating kidney transplant interstitial fibrosis and tubular atrophy: is the RAAS an important target?

PubMed

Amer, Hatem; Griffin, Matthew D

2014-02-01

In follow-up to a recently published randomized controlled clinical trial, Issa et al. provide evidence that systemic activity and physiological responsiveness of the renin aldosterone angiotensin system (RAAS) are well within normal limits in most kidney recipients during the first 5 years post-transplant. Implications of the results include the need to better understand intra-renal RAAS activity in transplanted kidneys and to identify patients in which the graft-protective effects of RAAS blockade are most relevant.

Personality, emotion, and individual differences in physiological responses.

PubMed

Stemmler, Gerhard; Wacker, Jan

2010-07-01

A dominant paradigm in biopsychological personality research seeks to establish links between emotional and motivational traits and habitual, transsituationally consistent individual differences in measures of physiological activity. An alternative approach conceptualizes traits as dispositions that are only operative in certain situational contexts and consequently predicts associations between emotional and motivational traits and physiological activity only for trait-relevant situational contexts in which the physiological systems underlying the traits in question are engaged. In the present paper we first examine and contrast these personistic and interactionistic conceptualizations of personality and personality-physiology associations and then present data from several large studies (N>100) in which electrocortical (e.g., frontal alpha asymmetry) and somatovisceral parameters were measured in various situational contexts (e.g., after the induction of either anger, or fear, or anxiety). As predicted by the interactionistic conceptualization of traits as dispositions the situational context and its subjective representation by the participants moderated the personality-physiology relationships for measures of both central and peripheral nervous system activity. We conclude by outlining the implications of the interactionistic approach for biopsychological personality research. Copyright © 2009 Elsevier B.V. All rights reserved.

Physiological and health implications of a sedentary lifestyle.

PubMed

Tremblay, Mark Stephen; Colley, Rachel Christine; Saunders, Travis John; Healy, Genevieve Nissa; Owen, Neville

2010-12-01

Sedentary behaviour is associated with deleterious health outcomes, which differ from those that can be attributed to a lack of moderate to vigorous physical activity. This has led to the field of "sedentary physiology", which may be considered as separate and distinct from exercise physiology. This paper gives an overview of this emerging area of research and highlights the ways that it differs from traditional exercise physiology. Definitions of key terms associated with the field of sedentary physiology and a review of the self-report and objective methods for assessing sedentary behaviour are provided. Proposed mechanisms of sedentary physiology are examined, and how they differ from those linking physical activity and health are highlighted. Evidence relating to associations of sedentary behaviours with major health outcomes and the population prevalence and correlates of sedentary behaviours are reviewed. Recommendations for future research are proposed.

Publications of the space physiology and countermeasures program, regulatory physiology discipline: 1980 - 1990

NASA Technical Reports Server (NTRS)

Wallace-Robinson, Janice; Dickson, Katherine J.; Hess, Elizabeth; Powers, Janet V.

1992-01-01

A 10-year cumulative bibliography of publications resulting from research supported by the Regulatory Physiology discipline of the Space Physiology and Countermeasures Program of NASA's Life Sciences Division is provided. Primary subjects included in this bibliography are circadian rhythms, endocrinology, fluid and electrolyte regulation, hematology, immunology, metabolism and nutrition, temperature regulation, and general regulatory physiology. General physiology references are also included. Principal investigators whose research tasks resulted in publication are identified by asterisk. Publications are identified by a record number corresponding with their entry in the Life Sciences Bibliographic Database, maintained at the George Washington University.

Physiological, Behavioral, and Histological Responses of Male C57BL/6N Mice to Different CO2 Chamber Replacement Rates

PubMed Central

Boivin, Gregory P; Bottomley, Michael A; Dudley, Emily S; Schiml, Patricia A; Wyatt, Christopher N; Grobe, Nadja

2016-01-01

Rodent euthanasia with CO2 by using gradual displacement of 10% to 30% of the chamber volume per minute is considered acceptable by the AVMA Panel on Euthanasia. However, whether a 50% to 100% chamber replacement rate (CRR) of CO2 is more painful or distressful than 10% to 30% CRR is unclear. Therefore, we examined physiological and behavioral parameters, corticosterone and ACTH levels, and lung histology of mice euthanized at CRR of 15%, 30%, 50%, or 100%. Adult male C57BL/6N mice were euthanized at different CO2 CRR as physiological parameters were recorded telemetrically. Video recordings were reviewed to determine when the mouse first became ataxic, when it was fully recumbent (characterized by the mouse's nose resting on the cage floor), and when breathing stopped. Overall, CO2 euthanasia increased cardiovascular parameters and activity. Specific significant differences that were associated with 50% to 100% compared with 15% to 30% CO2 CRR included an increase in systolic blood pressure per second from initiation of CO2 until ataxia, a decrease in total diastolic blood pressure until ataxia, and a decrease in total heart rate until ataxia, immobility, and death. All physiological responses occurred more rapidly with higher CRR. Activity levels, behavioral responses, plasma adrenocorticotropic hormone and corticosterone levels, and lung pathology were not different between groups. We found no physiological, behavioral, or histologic evidence that 15% or 30% CO2 CRR is less painful or distressful than is 50% or 100% CO2 CRR. We conclude that 50% to 100% CO2 CRR is acceptable for euthanizing adult male C57BL/6N mice. PMID:27423153

Synthetic lipids and their role in defining macromolecular assemblies.

PubMed

Parrill, Abby L

2015-10-01

Lipids have a variety of physiological roles, ranging from structural and biophysical contributions to membrane functions to signaling contributions in normal and abnormal physiology. This review highlights some of the contributions made by Robert Bittman to our understanding of lipid assemblies through the production of synthetic lipid analogs in the sterol, sphingolipid, and glycolipid classes. His contributions have included the development of a fluorescent cholesterol analog that shows strong functional analogies to cholesterol that has allowed live imaging of cholesterol distribution in living systems, to stereospecific synthetic approaches to both sphingolipid and glycolipid analogs crucial in defining the structure-activity relationships of lipid biological targets. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Do physical activity levels influence the cardiovascular-related physiological characteristics of postmenopausal women?

PubMed

Barnett, Fiona

2009-12-01

This study aimed to determine whether cardiovascular-related physiological differences existed among postmenopausal women in relation to their physical activity levels. Participants were postmenopausal women (n= 101) resident in North Queensland. A self-report questionnaire determined recent exercise history. Anthropometric and physiological measures were obtained. Participants also performed a six-minute graded exercise test to determine cardiorespiratory fitness. Compared with the women who exercised, those women who did not exercise had a lower level of cardiorespiratory fitness (P= 0.00) and higher resting diastolic blood pressure (P= 0.01), BMI (P= 0.00) and WHR (P= 0.02). Discriminant function analysis found that a combination of BMI and cardiorespiratory fitness discriminated between the two groups. Postmenopausal women who performed moderate-intensity physical activity had more favourable cardiovascular-related physiological characteristics. Health professionals should encourage more postmenopausal women to participate in moderate-intensity activity to reduce the risk of cardiovascular disease.

On the salty side of life: molecular, physiological and anatomical adaptation and acclimation of trees to extreme habitats.

PubMed

Polle, Andrea; Chen, Shaoliang

2015-09-01

Saline and sodic soils that cannot be used for agriculture occur worldwide. Cultivating stress-tolerant trees to obtain biomass from salinized areas has been suggested. Various tree species of economic importance for fruit, fibre and timber production exhibit high salinity tolerance. Little is known about the mechanisms enabling tree crops to cope with high salinity for extended periods. Here, the molecular, physiological and anatomical adjustments underlying salt tolerance in glycophytic and halophytic model tree species, such as Populus euphratica in terrestrial habitats, and mangrove species along coastlines are reviewed. Key mechanisms that have been identified as mediating salt tolerance are discussed at scales from the genetic to the morphological level, including leaf succulence and structural adjustments of wood anatomy. The genetic and transcriptomic bases for physiological salt acclimation are salt sensing and signalling networks that activate target genes; the target genes keep reactive oxygen species under control, maintain the ion balance and restore water status. Evolutionary adaptation includes gene duplication in these pathways. Strategies for and limitations to tree improvement, particularly transgenic approaches for increasing salt tolerance by transforming trees with single and multiple candidate genes, are discussed. © 2014 John Wiley & Sons Ltd.

GPER/GPR30 knockout mice: effects of GPER on metabolism

PubMed Central

Sharma, Geetanjali; Prossnitz, Eric R.

2015-01-01

i. Summary Endogenous estrogens, predominantly 17β-estradiol (E2), mediate various very diverse effects throughout the body in both normal physiology and disease. Actions include development (including puberty) and reproduction as well as additional effects throughout life in the metabolic, endocrine, musculoskeletal, nervous, cardiovascular and immune systems. The actions of E2 have traditionally been attributed to the classical nuclear estrogen receptors (ERα and ERβ) that largely mediate transcriptional/genomic activities. However, more recently the G protein-coupled estrogen receptor GPER/GPR30 has become recognized as an essential mediator of certain, and particularly rapid, signaling events in response to E2. Murine genetic knockout (KO) models represent an important approach to understand the mechanisms of E2 action in physiology and disease. Studies of GPER KO mice over the last years have revealed functions for GPER in the regulation of obesity, insulin resistance and glucose intolerance, among other areas of (patho)physiology. This chapter focuses on methods for the evaluation of metabolic parameters in vivo and ex vivo with an emphasis on glucose homeostasis and metabolism through the use of glucose and insulin tolerance tests, pancreatic islet and adipocyte isolation and characterization. PMID:26585159

GPER/GPR30 Knockout Mice: Effects of GPER on Metabolism.

PubMed

Sharma, Geetanjali; Prossnitz, Eric R

2016-01-01

Endogenous estrogens, predominantly 17β-estradiol (E2), mediate various diverse effects throughout the body in both normal physiology and disease. Actions include development (including puberty) and reproduction as well as additional effects throughout life in the metabolic, endocrine, musculoskeletal, nervous, cardiovascular, and immune systems. The actions of E2 have traditionally been attributed to the classical nuclear estrogen receptors (ERα and ERβ) that largely mediate transcriptional/genomic activities. However, more recently the G protein-coupled estrogen receptor GPER/GPR30 has become recognized as an essential mediator of certain, and particularly rapid, signaling events in response to E2. Murine genetic knockout (KO) models represent an important approach to understand the mechanisms of E2 action in physiology and disease. Studies of GPER KO mice over the last years have revealed functions for GPER in the regulation of obesity, insulin resistance and glucose intolerance, among other areas of (patho)physiology. This chapter focuses on methods for the evaluation of metabolic parameters in vivo and ex vivo with an emphasis on glucose homeostasis and metabolism through the use of glucose and insulin tolerance tests, pancreatic islet and adipocyte isolation and characterization.

Probiotics normalize the gut-brain-microbiota axis in immunodeficient mice

PubMed Central

Smith, Carli J.; Emge, Jacob R.; Berzins, Katrina; Lung, Lydia; Khamishon, Rebecca; Shah, Paarth; Rodrigues, David M.; Sousa, Andrew J.; Reardon, Colin; Sherman, Philip M.; Barrett, Kim E.

2014-01-01

The gut-brain-microbiota axis is increasingly recognized as an important regulator of intestinal physiology. Exposure to psychological stress causes activation of the hypothalamic-pituitary-adrenal (HPA) axis and causes altered intestinal barrier function, intestinal dysbiosis, and behavioral changes. The primary aim of this study was to determine whether the effects of psychological stress on intestinal physiology and behavior, including anxiety and memory, are mediated by the adaptive immune system. Furthermore, we wanted to determine whether treatment with probiotics would normalize these effects. Here we demonstrate that B and T cell-deficient Rag1−/− mice displayed altered baseline behaviors, including memory and anxiety, accompanied by an overactive HPA axis, increased intestinal secretory state, dysbiosis, and decreased hippocampal c-Fos expression. Both local (intestinal physiology and microbiota) and central (behavioral and hippocampal c-Fos) changes were normalized by pretreatment with probiotics, indicating an overall benefit on health conferred by changes in the microbiota, independent of lymphocytes. Taken together, these findings indicate a role for adaptive immune cells in maintaining normal intestinal and brain health in mice and show that probiotics can overcome this immune-mediated deficit in the gut-brain-microbiota axis. PMID:25190473

Use and physiological responses of portable dynamic office workstations in an occupational setting - A field study.

PubMed

Schellewald, Vera; Kleinert, Jens; Ellegast, Rolf

2018-09-01

The aim of this study was to investigate the use of two types of dynamic workstations (Deskbike, activeLife Trainer) and their effects on physiological activation in an occupational setting. 30 employees were given access to the devices for 28 days. Frequency and duration of borrowing and use was recorded by a Chipcard-system. Physiological activation (energy expenditure, heart rate) while working in a seated position and using the workstations was measured with the activity tracker Fitbit Charge HR. Participants used dynamic workstations on 40% of their working days for an average of 54.3 ± 23.9 min per day. Energy expenditure and heart rate increased significantly while using the workstations compared to working seated. The Deskbike was used more frequently and resulted in greater heart rate elevation. Both types of dynamic workstations were used by the employees and had positive effects on physiological activation. The implementation of either type can be recommended. Copyright © 2018 Elsevier Ltd. All rights reserved.

SP and KLF Transcription Factors in Digestive Physiology and Diseases.

PubMed

Kim, Chang-Kyung; He, Ping; Bialkowska, Agnieszka B; Yang, Vincent W

2017-06-01

Specificity proteins (SPs) and Krüppel-like factors (KLFs) belong to the family of transcription factors that contain conserved zinc finger domains involved in binding to target DNA sequences. Many of these proteins are expressed in different tissues and have distinct tissue-specific activities and functions. Studies have shown that SPs and KLFs regulate not only physiological processes such as growth, development, differentiation, proliferation, and embryogenesis, but pathogenesis of many diseases, including cancer and inflammatory disorders. Consistently, these proteins have been shown to regulate normal functions and pathobiology in the digestive system. We review recent findings on the tissue- and organ-specific functions of SPs and KLFs in the digestive system including the oral cavity, esophagus, stomach, small and large intestines, pancreas, and liver. We provide a list of agents under development to target these proteins. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

The reduced brood nursing by mite-infested honey bees depends on their accelerated behavioral maturation.

PubMed

Zanni, V; Değirmenci, L; Annoscia, D; Scheiner, R; Nazzi, F

2018-06-19

The parasitic mite Varroa destructor is regarded as the most important parasite of honey bees and plays a fundamental role in the decline of bee colonies observed in the last decade in the Northern hemisphere. Parasitization has a number of detrimental effects on bees, including reduced nursing, which can have important impacts on colony balance. In this work we investigated at the individual level the causes of this abnormal behavior and found that the reduced nursing activity in mite-infested workers is associated with impaired learning performance and a series of physiological traits that are typical of foragers, including reduced response to brood pheromone, limited development of hypopharyngeal glands and higher juvenile hormone titre in the haemolymph. Altogether our data confirm the premature transition to foraging already postulated based on previous genomics studies, from a physiological point of view. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hatching behavior in turtles.

PubMed

Spencer, Ricky-John; Janzen, Fredric J

2011-07-01

Incubation temperature plays a prominent role in shaping the phenotypes and fitness of embryos, including affecting developmental rates. In many taxa, including turtles, eggs are deposited in layers such that thermal gradients alter developmental rates within a nest. Despite this thermal effect, a nascent body of experimental work on environmentally cued hatching in turtles has revealed unexpected synchronicity in hatching behavior. This review discusses environmental cues for hatching, physiological mechanisms behind synchronous hatching, proximate and ultimate causes for this behavior, and future directions for research. Four freshwater turtle species have been investigated experimentally, with hatching in each species elicited by different environmental cues and responding via various physiological mechanisms. Hatching of groups of eggs in turtles apparently involves some level of embryo-embryo communication and thus is not a purely passive activity. Although turtles are not icons of complex social behavior, life-history theory predicts that the group environment of the nest can drive the evolution of environmentally cued hatching.

How Attributional Ambiguity Shapes Physiological and Emotional Responses to Social Rejection and Acceptance

PubMed Central

Mendes, Wendy Berry; McCoy, Shannon; Major, Brenda; Blascovich, Jim

2008-01-01

The authors examined White and Black participants’ emotional, physiological, and behavioral responses to same-race or different-race evaluators, following rejecting social feedback or accepting social feedback. As expected, in ingroup interactions, the authors observed deleterious responses to social rejection and benign responses to social acceptance. Deleterious responses included cardiovascular (CV) reactivity consistent with threat states and poorer performance, whereas benign responses included CV reactivity consistent with challenge states and better performance. In intergroup interactions, however, a more complex pattern of responses emerged. Social rejection from different-race evaluators engendered more anger and activational responses, regardless of participants’ race. In contrast, social acceptance produced an asymmetrical race pattern—White participants responded more positively than did Black participants. The latter appeared vigilant and exhibited threat responses. Discussion centers on implications for attributional ambiguity theory and potential pathways from discrimination to health outcomes. PMID:18211177

Developing psychophysiological profiles for monitoring stress

NASA Astrophysics Data System (ADS)

Moldow, Roberta L.; Bergen, Michael T.; Belin, Kari; Bululu, Luba; Couso, Olivita; McLaughlin, Joselyn; Short, Kenneth R.; Servatius, Richard J.

2006-05-01

Training prepares first responders for disasters including terrorist attacks. To train effectively it should be as realistic as possible and elicit the stress response. We are developing a profile that will be a marker for intensity of stress as well as differentiate stress from exertion. We have monitored stress during several training scenarios for different groups including civilian SWAT teams and the military. In addition, we can monitor stress to exposure to nonlethal weapons. We have monitored stress during exposure to blunt impact using a paintball paradigm. We have measured salivary substances (such as cortisol and DHEA [markers for the hypothalamic-pituitary-adrenal axis]) and amylase [marker for the sympathetic branch of the autonomic nervous system], physiological parameters (such as activity and heart rate), and neuropsychological assessment tools (such as Borg's perceived exertion scale, Spielberger's STAI and Thayer's ADC). With these neuroendocrine, physiological and behavioral indices in hand, we are poised to examine stress induction in preparedness in trainees.

We can't explore space without it - Common human space needs for exploration spaceflight

NASA Technical Reports Server (NTRS)

Daues, K. R.; Erwin, H. O.

1992-01-01

An overview is conducted of physiological, psychological, and human-interface requirements for manned spaceflight programs to establish common criteria. Attention is given to the comfort levels relevant to human support in exploration mission spacecraft and planetary habitats, and three comfort levels (CLs) are established. The levels include: (1) CL-1 for basic crew life support; (2) CL-2 for enabling the nominal completion of mission science; and (3) CL-3 which provides for enhanced life support and user-friendly interface systems. CL-2 support systems can include systems for EVA, workstations, and activity centers for repairs and enhanced utilization of payload and human/machine integration. CL-3 supports can be useful for maintaining crew psychological and physiological health as well as the design of comfortable and earthlike surroundings. While all missions require CL-1 commonality, CL-2 commonality is required only for EVA systems, display nomenclature, and restraint designs.

High-Flow-Rate Impinger for the Study of Concentration, Viability, Metabolic Activity, and Ice-Nucleation Activity of Airborne Bacteria.

PubMed

Šantl-Temkiv, Tina; Amato, Pierre; Gosewinkel, Ulrich; Thyrhaug, Runar; Charton, Anaïs; Chicot, Benjamin; Finster, Kai; Bratbak, Gunnar; Löndahl, Jakob

2017-10-03

The study of airborne bacteria relies on a sampling strategy that preserves their integrity and in situ physiological state, e.g. viability, cultivability, metabolic activity, and ice-nucleation activity. Because ambient air harbors low concentrations of bacteria, an effective bioaerosol sampler should have a high sampling efficiency and a high airflow. We characterize a high-flow-rate impinger with respect to particle collection and retention efficiencies in the range 0.5-3.0 μm, and we investigated its ability to preserve the physiological state of selected bacterial species and seawater bacterial community in comparison with four commercial bioaerosol samplers. The collection efficiency increased with particle size and the cutoff diameter was between 0.5 and 1 μm. During sampling periods of 120-300 min, the impinger retained the cultivability, metabolic activity, viability, and ice-nucleation activity of investigated bacteria. Field studies in semiurban, high-altitude, and polar environments included periods of low bacterial air concentrations, thus demonstrating the benefits of the impinger's high flow rate. In conclusion, the impinger described here has many advantages compared with other bioaerosol samplers currently on the market: a potential for long sampling time, a high flow rate, a high sampling and retention efficiency, low costs, and applicability for diverse downstream microbiological and molecular analyses.

Active physiology learning in a diverse class: an analysis of medical student responses in terms of sex, home language, and self-reported test performance.

PubMed

Higgins-Opitz, Susan B; Tufts, Mark

2012-06-01

The student body at the Nelson R. Mandela School of Medicine (NRMSM) is very diverse, representing many cultures, religions, and languages. Research has shown that weakness in English can impact student performance. Recent studies have also highlighted sex-based differences in students' learning and listening styles. These factors pose both challenges and opportunities for teachers of physiology. Student presentations were incorporated for a number of years into the traditional didactic second-year medical physiology curriculum at the NRMSM. Feedback obtained about the perceived benefits of these presentations for the learning of gastrointestinal and endocrine physiology included demographic data pertaining to students' sex, home language, and self-reported performance in tests. Analysis of the 50-item questionnaire responses, obtained over a 2-yr period, provided some interesting insights. Student responses to the items differed significantly in 27 of the 50 items in the questionnaire, based on sex alone (22%), sex and home language (7%), home language alone (37%), performance alone (26%), and performance and home language (7%). Our analyses of student perceptions support the findings of other studies and show that factors such as sex, home language, and student performance can play an important role in the way students are motivated to learn. In designing active learning strategies, academics need to take into account the potential influences that might affect student learning in diverse, multicultural, and multilingual classes.

Like cures like: a neuroimmunological model based on electromagnetic resonance.

PubMed

Shahabi, Shahram; Kasariyans, Aditya; Noorbakhsh, Farshid

2013-12-01

Recent investigations have pointed to the production of characteristic electromagnetic (EM) waves in highly diluted sterile filtrates of different microorganisms and their associated DNA molecules. Analysis of these diluted solutions that are prepared using methods almost identical to the way that homeopathic medicines are prepared has pointed to the existence of nanostructures capable of emitting EM waves. Combining these results with findings that point to the interaction of EM waves with sensory nerves with subsequent activation of homeostatic efferent pathways, we propose a model to describe mechanisms underlying the effects of homeopathic remedies. THE MODEL: Living cells and tissues are capable of generating EM waves in their physiological conditions. When a cell deviates from its physiological state, in addition to normal EM emissions, it starts to produce EM waves with altered characteristics. According to our model, the main cause of the therapeutic effects of homeopathic remedies is the occurrence of resonance between the non-physiological EM waves of the patient and extremely low-frequency EM waves produced by nanostructures present in the homeopathic remedy. Resonance occurs if the frequency and amplitude characteristics of the patient's non-physiological EM waves and those produced by nanostructures of the applied homeopathic remedy are similar. Once resonance occurs, stimulation of the patient's sensory neurons, which are sensitized due to inflammation of any origin, leads to triggering of different regulatory mechanisms, including the activation of descending antinociceptive and/or cholinergic anti-inflammatory pathways, which leads to the restoration of homeostasis.

Yoga clinical research review.

PubMed

Field, Tiffany

2011-02-01

In this paper recent research is reviewed on the effects of yoga poses on psychological conditions including anxiety and depression, on pain syndromes, cardiovascular, autoimmune and immune conditions and on pregnancy. Further, the physiological effects of yoga including decreased heartrate and blood pressure and the physical effects including weight loss and increased muscle strength are reviewed. Finally, potential underlying mechanisms are proposed including the stimulation of pressure receptors leading to enhanced vagal activity and reduced cortisol. The reduction in cortisol, in turn, may contribute to positive effects such as enhanced immune function and a lower prematurity rate. Copyright © 2010 Elsevier Ltd. All rights reserved.

Outside of the laboratory: Associations of working-memory performance with psychological and physiological arousal vary with age.

PubMed

Riediger, Michaela; Wrzus, Cornelia; Klipker, Kathrin; Müller, Viktor; Schmiedek, Florian; Wagner, Gert G

2014-03-01

We investigated age differences in associations among self-reported experiences of tense and energetic arousal, physiological activation indicated by heart rate, and working-memory performance in everyday life. The sample comprised 92 participants aged 14-83 years. Data were collected for 24 hr while participants pursued their normal daily routines. Participants wore an ambulatory biomonitoring system that recorded their cardiac and physical activity. Using mobile phones as assessment devices, they also provided an average of 7 assessments of their momentary experiences of tense arousal (feeling nervous) and energetic arousal (feeling wide-awake) and completed 2 trials of a well-practiced working-memory task. Experiences of higher energetic arousal were associated with higher heart rate in participants younger than 50 years of age but not in participants older than that, and energetic arousal was unrelated to within-person fluctuations in working-memory performance. Experiences of tense arousal were associated with higher heart rate independent of participants' age. Tense arousal and physiological activation were accompanied by momentary impairments in working-memory performance in middle-aged and older adults but not in younger individuals. Results suggest that psychological arousal experiences are associated with lower working-memory performance in middle-aged and older adults when they are accompanied by increased physiological activation and that the same is true for physiological activation deriving from other influences. Hence, age differences in cognitive performance may be exaggerated when the assessment situation itself elicits tense arousal or occurs in situations with higher physiological arousal arising from affective experiences, physical activity, or circadian rhythms. (c) 2014 APA, all rights reserved.

Determining environmental causes of biological effects: the need for a mechanistic physiological dimension in conservation biology.

PubMed

Seebacher, Frank; Franklin, Craig E

2012-06-19

The emerging field of Conservation Physiology links environmental change and ecological success by the application of physiological theory, approaches and tools to elucidate and address conservation problems. Human activity has changed the natural environment to a point where the viability of many ecosystems is now under threat. There are already many descriptions of how changes in biological patterns are correlated with environmental changes. The next important step is to determine the causative relationship between environmental variability and biological systems. Physiology provides the mechanistic link between environmental change and ecological patterns. Physiological research, therefore, should be integrated into conservation to predict the biological consequences of human activity, and to identify those species or populations that are most vulnerable.

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…

[P21-activated kinases and their role in the nervous system].

PubMed

Qin, Yuan; Ding, Yue-Min; Xia, Qiang

2012-12-25

P21-activated kinases (PAK) participate in a variety of important cellular activities, such as cytoskeleton remodeling, cell migration, cell cycle regulation, and apoptosis or survival. PAK also has an important impact on brain development, neuronal differentiation, and regulation of synaptic plasticity in the nervous system. PAK abnormalities result in diseases including cancer, Parkinson's disease (PD), Alzheimer's disease (AD) and neural retardation. Therefore, it is of vital physiological significance to investigate the neuronal function of PAK. In this paper we review the advancement of research on the neuronal biological function and the underlying mechanisms of PAK.

Astronaut training manual

NASA Technical Reports Server (NTRS)

Coleman, E. A.

1980-01-01

Scientific information from previous space flights, space medicine, exercise physiology, and sports medicine was used to prepare a physical fitness manual suitable for use by members of the NASA astronaut population. A variety of scientifically valid exercise programs and activities suitable for the development of physical fitness are provided. Programs, activities, and supportive scientific data are presented in a concise, easy to read format so as to permit the user to select his or her mode of training with confidence and devote time previously spent experimenting with training routines to preparation for space flight. The programs and activities included were tested and shown to be effective and enjoyable.

Microbial stress-response physiology and its implications for ecosystem function.

PubMed

Schimel, Joshua; Balser, Teri C; Wallenstein, Matthew

2007-06-01

Microorganisms have a variety of evolutionary adaptations and physiological acclimation mechanisms that allow them to survive and remain active in the face of environmental stress. Physiological responses to stress have costs at the organismal level that can result in altered ecosystem-level C, energy, and nutrient flows. These large-scale impacts result from direct effects on active microbes' physiology and by controlling the composition of the active microbial community. We first consider some general aspects of how microbes experience environmental stresses and how they respond to them. We then discuss the impacts of two important ecosystem-level stressors, drought and freezing, on microbial physiology and community composition. Even when microbial community response to stress is limited, the physiological costs imposed on soil microbes are large enough that they may cause large shifts in the allocation and fate of C and N. For example, for microbes to synthesize the osmolytes they need to survive a single drought episode they may consume up to 5% of total annual net primary production in grassland ecosystems, while acclimating to freezing conditions switches Arctic tundra soils from immobilizing N during the growing season to mineralizing it during the winter. We suggest that more effectively integrating microbial ecology into ecosystem ecology will require a more complete integration of microbial physiological ecology, population biology, and process ecology.

Differential Activation of Pontomedullary Nuclei by Acid Perfusion of Different Regions of the Esophagus

PubMed Central

Lang, Ivan M.; Medda, Bidyut K.; Shaker, Reza

2010-01-01

The objective of this study was to determine the brain stem nuclei and physiological responses activated by esophageal acidification. The effects of perfusion of the cervical (ESOc), or thoracic (ESOt) esophagus with PBS or HCl on c-fos immunoreactivity of the brain stem or on physiological variables, and the effects of vagotomy were examined in anesthetized cats. We found that acidification of the ESOc increased the number of c-fos positive neurons in the area postrema (AP), vestibular nucleus (VN), parabrachial nucleus (PBN), nucleus ambiguus (NA), dorsal motor nucleus (DMN), and all subnuclei of the nucleus tractus solitarius (NTS), but one. Acidification of the ESOt activated neurons in the central (CE), caudal (CD), dorsomedial (DM), dorsolateral (DL), ventromedial (VM) subnuclei of NTS, and the DMN. Vagotomy blocked all c-fos responses to acid perfusion of the whole esophagus (ESOw). Perfusion of the ESOc or ESOt with PBS activated secondary peristalsis (2P), but had no effect on blood pressure, heart rate, or respiratory rate. Perfusion of the ESOc, but not ESOt, with HCL activated pharyngeal swallowing (PS), profuse salivation, or physiological correlates of emesis. Vagotomy blocked all physiological effects of ESOw perfusion. We conclude that acidification of the ESOc and ESOt activate different sets of pontomedullary nuclei and different physiological responses. The NTSce, NTScom, NTSdm, and DMN are associated with activation of 2P, the NTSim and NTSis, are associated with activation of PS, and the AP, VN, and PBN are associated with activation of emesis and perhaps nausea. All responses to esophageal fluid perfusion or acidification are mediated by the vagus nerves. PMID:20655885

Controversial constitutive TSHR activity: patients, physiology, and in vitro characterization.

PubMed

Huth, S; Jaeschke, H; Schaarschmidt, J; Paschke, R

2014-06-01

G protein-coupled receptors constitute a large family of transmembrane receptors, which activate cellular responses by signal transmission and regulation of second messenger metabolism after ligand binding. For several of these receptors it is known that they also signal ligand-independently. The G protein-coupled thyroid stimulating hormone receptor (TSHR) is characterized by a high level of constitutive activity in the wild type state. However, little is known yet concerning the physiological relevance of the constitutive wild type TSHR activity. Certainly, knowledge of the physiological relevance of constitutive wild type receptor activity is necessary to better understand thyroid physiology and it is a prerequisite for the development of better therapies for nonautoimmune hyperthyroidism and thyroid cancer. Based on a literature search regarding all published TSHR mutations, this review covers several mutations which are clearly associated with a hyperthyroidism-phenotype, but interestingly show a lack of constitutive activity determined by in vitro characterization. Possible reasons for the observed discrepancies between clinical phenotypes and in vitro characterization results for constitutive TSHR activity are reviewed. All current in vitro characterization methods for constitutive TSHR mutations are "preliminary attempts" and may well be revised by more comprehensive and even better approaches. However, a standardized approach for the determination of constitutive activity can help to identify TSHR mutations for which the investigation of additional signaling mechanisms would be most interesting to find explanations for the current clinical phenotype/in vitro discrepancies and thereby also define suitable methods to explore the physiological relevance of constitutive wild type TSHR activity. © Georg Thieme Verlag KG Stuttgart · New York.

Microbial physiology-based model of ethanol metabolism in subsurface sediments

NASA Astrophysics Data System (ADS)

Jin, Qusheng; Roden, Eric E.

2011-07-01

A biogeochemical reaction model was developed based on microbial physiology to simulate ethanol metabolism and its influence on the chemistry of anoxic subsurface environments. The model accounts for potential microbial metabolisms that degrade ethanol, including those that oxidize ethanol directly or syntrophically by reducing different electron acceptors. Out of the potential metabolisms, those that are active in the environment can be inferred by fitting the model to experimental observations. This approach was applied to a batch sediment slurry experiment that examined ethanol metabolism in uranium-contaminated aquifer sediments from Area 2 at the U.S. Department of Energy Field Research Center in Oak Ridge, TN. According to the simulation results, complete ethanol oxidation by denitrification, incomplete ethanol oxidation by ferric iron reduction, ethanol fermentation to acetate and H 2, hydrogenotrophic sulfate reduction, and acetoclastic methanogenesis: all contributed significantly to the degradation of ethanol in the aquifer sediments. The assemblage of the active metabolisms provides a frame work to explore how ethanol amendment impacts the chemistry of the environment, including the occurrence and levels of uranium. The results can also be applied to explore how diverse microbial metabolisms impact the progress and efficacy of bioremediation strategies.

Physiologically-Based Pharmacokinetic Modeling of Macitentan: Prediction of Drug-Drug Interactions.

PubMed

de Kanter, Ruben; Sidharta, Patricia N; Delahaye, Stéphane; Gnerre, Carmela; Segrestaa, Jerome; Buchmann, Stephan; Kohl, Christopher; Treiber, Alexander

2016-03-01

Macitentan is a novel dual endothelin receptor antagonist for the treatment of pulmonary arterial hypertension (PAH). It is metabolized by cytochrome P450 (CYP) enzymes, mainly CYP3A4, to its active metabolite ACT-132577. A physiological-based pharmacokinetic (PBPK) model was developed by combining observations from clinical studies and physicochemical parameters as well as absorption, distribution, metabolism and excretion parameters determined in vitro. The model predicted the observed pharmacokinetics of macitentan and its active metabolite ACT-132577 after single and multiple dosing. It performed well in recovering the observed effect of the CYP3A4 inhibitors ketoconazole and cyclosporine, and the CYP3A4 inducer rifampicin, as well as in predicting interactions with S-warfarin and sildenafil. The model was robust enough to allow prospective predictions of macitentan-drug combinations not studied, including an alternative dosing regimen of ketoconazole and nine other CYP3A4-interacting drugs. Among these were the HIV drugs ritonavir and saquinavir, which were included because HIV infection is a known risk factor for the development of PAH. This example of the application of PBPK modeling to predict drug-drug interactions was used to support the labeling of macitentan (Opsumit).

Formation of a physiological complex between TRPV2 and RGA protein promotes cell surface expression of TRPV2.

PubMed

Stokes, Alexander J; Wakano, Clay; Del Carmen, Kimberly A; Koblan-Huberson, Murielle; Turner, Helen

2005-03-01

The transient receptor potential, sub-family Vanilloid (TRPV)(2) cation channel is activated in response to extreme temperature elevations in sensory neurons. However, TRPV2 is widely expressed in tissues with no sensory function, including cells of the immune system. Regulation of GRC, the murine homolog of TRPV2 has been studied in insulinoma cells and myocytes. GRC is activated in response to certain growth factors and neuropeptides, via a mechanism that involves regulated access of the channel to the plasma membrane. This is likely to be an important primary control mechanism for TRPV2 outside the CNS. Here, we report that a regulated trafficking step controls the access of TRPV2 to the cell surface in mast cells. In mast cells, elevations in cytosolic cAMP are sufficient to drive plasma membrane localization of TRPV2. We have previously proposed that the recombinase gene activator protein (RGA), a four-transmembrane domain, intracellular protein, associates with TRPV2 during the biosynthesis and early trafficking of the channel. We use a polyclonal antibody to RGA to confirm the formation of a physiological complex between RGA and TRPV2. Finally, we show that over-expression of the RGA protein potentiates the basal surface localization of TRPV2. We propose that trafficking and activation mechanisms intersect for TRPV2, and that cAMP mobilizing stimuli may regulate TRPV2 localization in non-sensory cells. RGA participates in the control of TRPV2 surface levels, and co-expression of RGA may be a key component of experimental systems that seek to study TRPV2 physiology.

Evaluation of physiological stress in Australian wildlife: Embracing pioneering and current knowledge as a guide to future research directions.

PubMed

Narayan, Edward J

2017-04-01

Australia has a rich terrestrial and marine biodiversity and high species endemism. However, the oceanic continent is facing the biodiversity extinction crisis. The primary factors are anthropogenic induced environmental changes, including wildlife habitat destruction through urbanisation and predation by feral animals (e.g. red foxes and feral cats), increased severity of diseases (e.g. chytridiomycosis and chlamydia), and increased occurrence of summer heat waves and bush fires. Stress physiology is a dynamic field of science based on the studies of endocrine system functioning in animals. The primary stress regulator is the hypothalamo-pituitary adrenal (interrenal) axis and glucocorticoids (corticosterone and/or cortisol) provide stress index across vertebrate groups. This review paper focuses on physiological stress assessments in Australian wildlife using examples of amphibians, reptiles, birds and marsupials. I provide a thorough discussion of pioneering studies that have shaped the field of stress physiology in Australian wildlife species. The main findings point towards key aspects of stress endocrinology research, such as quantification of biologically active levels of glucocorticoids, development of species-specific GC assays and applications of stress physiology approaches in field ecology and wildlife conservation programs. Furthermore, I also discuss the importance of chronic stress assessment in wildlife populations. Finally, I provide a conceptual framework presenting key research questions in areas of wildlife stress physiology research. In conclusion, wildlife management programs can immensely benefit from stress physiology assessments to gauge the impact of human interventions on wildlife such as species translocation and feral species eradication. Copyright © 2015 Elsevier Inc. All rights reserved.

Emotional effects of startling background music during reading news reports: The moderating influence of dispositional BIS and BAS sensitivities.

PubMed

Ravaja, Niklas; Kallinen, Kari

2004-07-01

We examined the moderating influence of dispositional behavioral inhibition system (BIS) and behavioral activation system (BAS) sensitivities on the relationship of startling background music with emotion-related subjective and physiological responses elicited during reading news reports, and with memory performance among 26 adult men and women. Physiological parameters measured were respiratory sinus arrhythmia (RSA), electrodermal activity (EDA), and facial electromyography (EMG). The results showed that, among high BAS individuals, news stories with startling background music were rated as more interesting and elicited higher zygomatic EMG activity and RSA than news stories with non-startling music. Among low BAS individuals, news stories with startling background music were rated as less pleasant and more arousing and prompted higher EDA. No BIS-related effects or effects on memory were found. Startling background music may have adverse (e.g., negative arousal) or beneficial effects (e.g., a positive emotional state and stronger positive engagement) depending on dispositional BAS sensitivity of an individual. Actual or potential applications of this research include the personalization of media presentations when using modern media and communications technologies.

Does the vestibular system contribute to head direction cell activity in the rat?

NASA Technical Reports Server (NTRS)

Brown, J. E.; Yates, B. J.; Taube, J. S.; Oman, C. M. (Principal Investigator)

2002-01-01

Head direction cells (HDC) located in several regions of the brain, including the anterior dorsal nucleus of the thalamus (ADN), postsubiculum (PoS), and lateral mammillary nuclei (LMN), provide the neural substrate for the determination of head direction. Although activity of HDC is influenced by various sensory signals and internally generated cues, lesion studies and some anatomical and physiological evidence suggest that vestibular inputs are critical for the maintenance of directional sensitivity of these cells. However, vestibular inputs must be transformed considerably in order to signal head direction, and the neuronal circuitry that accomplishes this signal processing has not been fully established. Furthermore, it is unclear why the removal of vestibular inputs abolishes the directional sensitivity of HDC, as visual and other sensory inputs and motor feedback signals strongly affect the firing of these neurons and would be expected to maintain their directional-related activity. Further physiological studies will be required to establish the role of vestibular system in producing HDC responses, and anatomical studies are needed to determine the neural circuitry that mediates vestibular influences on determination of head direction.

[Stress-induced cellular adaptive mutagenesis].

PubMed

Zhu, Linjiang; Li, Qi

2014-04-01

The adaptive mutations exist widely in the evolution of cells, such as antibiotic resistance mutations of pathogenic bacteria, adaptive evolution of industrial strains, and cancerization of human somatic cells. However, how these adaptive mutations are generated is still controversial. Based on the mutational analysis models under the nonlethal selection conditions, stress-induced cellular adaptive mutagenesis is proposed as a new evolutionary viewpoint. The hypothetic pathway of stress-induced mutagenesis involves several intracellular physiological responses, including DNA damages caused by accumulation of intracellular toxic chemicals, limitation of DNA MMR (mismatch repair) activity, upregulation of general stress response and activation of SOS response. These responses directly affect the accuracy of DNA replication from a high-fidelity manner to an error-prone one. The state changes of cell physiology significantly increase intracellular mutation rate and recombination activity. In addition, gene transcription under stress condition increases the instability of genome in response to DNA damage, resulting in transcription-associated DNA mutagenesis. In this review, we summarize these two molecular mechanisms of stress-induced mutagenesis and transcription-associated DNA mutagenesis to help better understand the mechanisms of adaptive mutagenesis.

Genetic dissection of endothelial transcriptional activity of zebrafish aryl hydrocarbon receptors (AHRs).

PubMed

Sugden, Wade W; Leonardo-Mendonça, Roberto C; Acuña-Castroviejo, Darío; Siekmann, Arndt F

2017-01-01

The aryl hydrocarbon receptor (AHR) is a basic helix-loop-helix transcription factor conserved across phyla from flies to humans. Activated by a number of endogenous ligands and environmental toxins, studies on AHR function and gene regulation have largely focused on a toxicological perspective relating to aromatic hydrocarbons generated by human activities and the often-deleterious effects of exposure on vertebrates mediated by AHR activation. A growing body of work has highlighted the importance of AHR in physiologic processes, including immune cell differentiation and vascular patterning. Here we dissect the contribution of the 3 zebrafish AHRs, ahr1a, ahr1b and ahr2, to endothelial cyp1a1/b1 gene regulation under physiologic conditions and upon exposure to the AHR ligand Beta-naphthoflavone. We show that in fish multiple AHRs are functional in the vasculature, with vessel-specific differences in the ability of ahr1b to compensate for the loss of ahr2 to maintain AHR signaling. We further provide evidence that AHR can regulate the expression of the chemokine receptor cxcr4a in endothelial cells, a regulatory mechanism that may provide insight into AHR function in the endothelium.

Inhibition of acid sphingomyelinase disrupts LYNUS signaling and triggers autophagy.

PubMed

Justice, Matthew J; Bronova, Irina; Schweitzer, Kelly S; Poirier, Christophe; Blum, Janice S; Berdyshev, Evgeny V; Petrache, Irina

2018-04-01

Activation of the lysosomal ceramide-producing enzyme, acid sphingomyelinase (ASM), by various stresses is centrally involved in cell death and has been implicated in autophagy. We set out to investigate the role of the baseline ASM activity in maintaining physiological functions of lysosomes, focusing on the lysosomal nutrient-sensing complex (LYNUS), a lysosomal membrane-anchored multiprotein complex that includes mammalian target of rapamycin (mTOR) and transcription factor EB (TFEB). ASM inhibition with imipramine or sphingomyelin phosphodiesterase 1 ( SMPD1 ) siRNA in human lung cells, or by transgenic Smpd1 +/- haploinsufficiency of mouse lungs, markedly reduced mTOR- and P70-S6 kinase (Thr 389)-phosphorylation and modified TFEB in a pattern consistent with its activation. Inhibition of baseline ASM activity significantly increased autophagy with preserved degradative potential. Pulse labeling of sphingolipid metabolites revealed that ASM inhibition markedly decreased sphingosine (Sph) and Sph-1-phosphate (S1P) levels at the level of ceramide hydrolysis. These findings suggest that ASM functions to maintain physiological mTOR signaling and inhibit autophagy and implicate Sph and/or S1P in the control of lysosomal function. Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.

Polysaccharopeptides of Coriolus versicolor: physiological activity, uses, and production.

PubMed

Cui, Jian; Chisti, Yusuf

2003-04-01

The protein-bound polysaccharides or polysaccharopeptides produced by Coriolus versicolor are effective immunopotentiators, which are used to supplement the chemotherapy and radiotherapy of cancers and various infectious diseases. Antitumor activity of polysaccharopeptides has been documented. Several kinds of protein-bound polysaccharides have been shown to be produced by the white rot fungus, C. versicolor. Although some of these polymers are structurally distinct, they are not distinguishable in terms of their physiological activity. This review focuses on the physiologically active polysaccharopeptides of C. versicolor. In nature, C. versicolor occurs as a mushroom body, but the fungus can be grown as mycelial biomass in submerged culture in bioreactors. Mushrooms gathered in the wild, cultivated mushrooms, and the mycelial biomass of submerged culture are used to produce the polysaccharopeptides. Submerged cultures are typically carried out in batches lasting 5-7 days and at 25-27 degrees C. Hot water extraction of the biomass is used to recover the thermostable polysaccharopeptides that are concentrated, purified, and dried into a powder for medicinal use. In view of the documented physiological benefits of these compounds, extensive research is underway on the structure, composition, production methods, and use of new C. versicolor strains for producing the therapeutic biopolymers. Properties, physiological activity, recovery, and purification of the bioactive polysaccharopeptides are discussed.

The not-so-bitter pill: Effects of combined oral contraceptives on peripheral physiological indicators of emotional reactivity.

PubMed

Armbruster, Diana; Kirschbaum, Clemens; Strobel, Alexander

2017-08-01

Combined oral contraceptives (COC) are used by millions of women worldwide. Although findings are not entirely consistent, COC have been found to impact on brain function and, thus, to modulate affective processes. Here, we investigated electro-physiological responses to emotional stimuli in free cycling women in both the early follicular and late luteal phase as well as in COC users. Skin conductance response (SCR), startle reflex, corrugator and zygomaticus activity were assessed. COC users showed reduced overall startle magnitude and SCR amplitude, but heightened overall zygomaticus activity, although effect sizes were small. Thus, COC users displayed reduced physiological reactions indicating negative affect and enhanced physiological responses signifying positive affect. In free cycling women, endogenous 17β-estradiol levels were associated with fear potentiated startle in both cycle phases as well as with SCR and zygomaticus activity during the follicular phase. Testosterone was associated with corrugator and zygomaticus activity during the luteal phase, while progesterone levels correlated with corrugator activity in the follicular phase. To the contrary, in COC users, endogenous hormones were not associated with electro-physiological measures. The results further underscore the importance of considering COC use in psychophysiological studies on emotional processing. Copyright © 2017 Elsevier Inc. All rights reserved.

A Mechanism of Intracellular P2X Receptor Activation*

PubMed Central

Sivaramakrishnan, Venketesh; Fountain, Samuel J.

2012-01-01

P2X receptors (P2XRs) are ATP-activated calcium-permeable ligand-gated ion channels traditionally viewed as sensors of extracellular ATP during diverse physiological processes including pain, inflammation, and taste. However, in addition to a cell surface residency P2XRs also populate the membranes of intracellular compartments, including mammalian lysosomes, phagosomes, and the contractile vacuole (CV) of the amoeba Dictyostelium. The function of intracellular P2XRs is unclear and represents a major gap in our understanding of ATP signaling. Here, we exploit the genetic versatility of Dictyostelium to investigate the effects of physiological concentrations of ATP on calcium signaling in isolated CVs. Within the CV, an acidic calcium store, P2XRs are orientated to sense luminal ATP. Application of ATP to isolated vacuoles leads to luminal translocation of ATP and release of calcium. Mechanisms of luminal ATP translocation and ATP-evoked calcium release share common pharmacology, suggesting that they are linked processes. The ability of ATP to mobilize stored calcium is reduced in vacuoles isolated from P2XAR knock-out amoeba and ablated in cells devoid of P2XRs. Pharmacological inhibition of luminal ATP translocation or depletion of CV calcium attenuates CV function in vivo, manifesting as a loss of regulatory cell volume decrease following osmotic swelling. We propose that intracellular P2XRs regulate vacuole activity by acting as calcium release channels, activated by translocation of ATP into the vacuole lumen. PMID:22736763

Publications of the Space Physiology and Countermeasures Program, Cardiopulmonary Discipline: 1980-1990

NASA Technical Reports Server (NTRS)

Powers, Janet V.; Wallace-Robinson, Janice; Dickson, Katherine J.; Hess, Elizabeth

1992-01-01

A 10-year cumulative bibliography of publications resulting from research supported by the Cardiopulmonary Discipline of the Space Physiology and Countermeasures Program of NASA's Life Sciences Division is provided. Primary subjects included in this bibliography are Fluid Shifts, Cardiovascular Fitness, Cardiovascular Physiology, and Pulmonary Physiology. General physiology references are also included. Principal investigators whose research tasks resulted in publication are identified. Publications are identified by a record number corresponding with their entry in the Life Sciences Bibliographic Database, maintained at the George Washington University.

GLIS1-3 transcription factors: critical roles in the regulation of multiple physiological processes and diseases.

PubMed

Jetten, Anton M

2018-05-19

Krüppel-like zinc finger proteins form one of the largest families of transcription factors. They function as key regulators of embryonic development and a wide range of other physiological processes, and are implicated in a variety of pathologies. GLI-similar 1-3 (GLIS1-3) constitute a subfamily of Krüppel-like zinc finger proteins that act either as activators or repressors of gene transcription. GLIS3 plays a critical role in the regulation of multiple biological processes and is a key regulator of pancreatic β cell generation and maturation, insulin gene expression, thyroid hormone biosynthesis, spermatogenesis, and the maintenance of normal kidney functions. Loss of GLIS3 function in humans and mice leads to the development of several pathologies, including neonatal diabetes and congenital hypothyroidism, polycystic kidney disease, and infertility. Single nucleotide polymorphisms in GLIS3 genes have been associated with increased risk of several diseases, including type 1 and type 2 diabetes, glaucoma, and neurological disorders. GLIS2 plays a critical role in the kidney and GLIS2 dysfunction leads to nephronophthisis, an end-stage, cystic renal disease. In addition, GLIS1-3 have regulatory functions in several stem/progenitor cell populations. GLIS1 and GLIS3 greatly enhance reprogramming efficiency of somatic cells into induced embryonic stem cells, while GLIS2 inhibits reprogramming. Recent studies have obtained substantial mechanistic insights into several physiological processes regulated by GLIS2 and GLIS3, while a little is still known about the physiological functions of GLIS1. The localization of some GLIS proteins to the primary cilium suggests that their activity may be regulated by a downstream primary cilium-associated signaling pathway. Insights into the upstream GLIS signaling pathway may provide opportunities for the development of new therapeutic strategies for diabetes, hypothyroidism, and other diseases.

The role of transient receptor potential channels in joint diseases.

PubMed

Krupkova, O; Zvick, J; Wuertz-Kozak, K

2017-10-10

Transient receptor potential channels (TRP channels) are cation selective transmembrane receptors with diverse structures, activation mechanisms and physiological functions. TRP channels act as cellular sensors for a plethora of stimuli, including temperature, membrane voltage, oxidative stress, mechanical stimuli, pH and endogenous, as well as, exogenous ligands, thereby illustrating their versatility. As such, TRP channels regulate various functions in both excitable and non-excitable cells, mainly by mediating Ca2+ homeostasis. Dysregulation of TRP channels is implicated in many pathologies, including cardiovascular diseases, muscular dystrophies and hyperalgesia. However, the importance of TRP channel expression, physiological function and regulation in chondrocytes and intervertebral disc (IVD) cells is largely unexplored. Osteoarthritis (OA) and degenerative disc disease (DDD) are chronic age-related disorders that significantly affect the quality of life by causing pain, activity limitation and disability. Furthermore, currently available therapies cannot effectively slow-down or stop progression of these diseases. Both OA and DDD are characterised by reduced tissue cellularity, enhanced inflammatory responses and molecular, structural and mechanical alterations of the extracellular matrix, hence affecting load distribution and reducing joint flexibility. However, knowledge on how chondrocytes and IVD cells sense their microenvironment and respond to its changes is still limited. In this review, we introduced six families of mammalian TRP channels, their mechanisms of activation, as well as, activation-driven cellular consequences. We summarised the current knowledge on TRP channel expression and activity in chondrocytes and IVD cells, as well as, the significance of TRP channels as therapeutic targets for the treatment of OA and DDD.

Modeling fMRI signals can provide insights into neural processing in the cerebral cortex.

PubMed

Vanni, Simo; Sharifian, Fariba; Heikkinen, Hanna; Vigário, Ricardo

2015-08-01

Every stimulus or task activates multiple areas in the mammalian cortex. These distributed activations can be measured with functional magnetic resonance imaging (fMRI), which has the best spatial resolution among the noninvasive brain imaging methods. Unfortunately, the relationship between the fMRI activations and distributed cortical processing has remained unclear, both because the coupling between neural and fMRI activations has remained poorly understood and because fMRI voxels are too large to directly sense the local neural events. To get an idea of the local processing given the macroscopic data, we need models to simulate the neural activity and to provide output that can be compared with fMRI data. Such models can describe neural mechanisms as mathematical functions between input and output in a specific system, with little correspondence to physiological mechanisms. Alternatively, models can be biomimetic, including biological details with straightforward correspondence to experimental data. After careful balancing between complexity, computational efficiency, and realism, a biomimetic simulation should be able to provide insight into how biological structures or functions contribute to actual data processing as well as to promote theory-driven neuroscience experiments. This review analyzes the requirements for validating system-level computational models with fMRI. In particular, we study mesoscopic biomimetic models, which include a limited set of details from real-life networks and enable system-level simulations of neural mass action. In addition, we discuss how recent developments in neurophysiology and biophysics may significantly advance the modelling of fMRI signals. Copyright © 2015 the American Physiological Society.

Warm-Up Strategies for Sport and Exercise: Mechanisms and Applications.

PubMed

McGowan, Courtney J; Pyne, David B; Thompson, Kevin G; Rattray, Ben

2015-11-01

It is widely accepted that warming-up prior to exercise is vital for the attainment of optimum performance. Both passive and active warm-up can evoke temperature, metabolic, neural and psychology-related effects, including increased anaerobic metabolism, elevated oxygen uptake kinetics and post-activation potentiation. Passive warm-up can increase body temperature without depleting energy substrate stores, as occurs during the physical activity associated with active warm-up. While the use of passive warm-up alone is not commonplace, the idea of utilizing passive warming techniques to maintain elevated core and muscle temperature throughout the transition phase (the period between completion of the warm-up and the start of the event) is gaining in popularity. Active warm-up induces greater metabolic changes, leading to increased preparedness for a subsequent exercise task. Until recently, only modest scientific evidence was available supporting the effectiveness of pre-competition warm-ups, with early studies often containing relatively few participants and focusing mostly on physiological rather than performance-related changes. External issues faced by athletes pre-competition, including access to equipment and the length of the transition/marshalling phase, have also frequently been overlooked. Consequently, warm-up strategies have continued to develop largely on a trial-and-error basis, utilizing coach and athlete experiences rather than scientific evidence. However, over the past decade or so, new research has emerged, providing greater insight into how and why warm-up influences subsequent performance. This review identifies potential physiological mechanisms underpinning warm-ups and how they can affect subsequent exercise performance, and provides recommendations for warm-up strategy design for specific individual and team sports.

A Blended Approach to Active Learning in a Physiology Laboratory-Based Subject Facilitated by an e-Learning Component

ERIC Educational Resources Information Center

Dantas, Arianne M.; Kemm, Robert E.

2008-01-01

Learning via online activities (e-learning) was introduced to facilitate existing face-to-face teaching to encourage more effective student preparation and then informed participation in an undergraduate physiology laboratory-based course. Active learning was encouraged by hypothesis formation and predictions prior to classes, with opportunities…

New physiologically-relevant liver tissue model based on hierarchically cocultured primary rat hepatocytes with liver endothelial cells.

PubMed

Xiao, Wenjin; Perry, Guillaume; Komori, Kikuo; Sakai, Yasuyuki

2015-11-01

To develop an in vitro liver tissue equivalent, hepatocytes should be cocultured with liver non-parenchymal cells to mimic the in vivo physiological microenvironments. In this work, we describe a physiologically-relevant liver tissue model by hierarchically organizing layers of primary rat hepatocytes and human liver sinusoidal endothelial cells (TMNK-1) on an oxygen-permeable polydimethylsiloxane (PDMS) membrane, which facilitates direct oxygenation by diffusion through the membrane. This in vivo-mimicking hierarchical coculture was obtained by simply proceeding the overlay of TMNK-1 cells on the hepatocyte layer re-formed on the collagen immobilized PDMS membranes. The comparison of hepatic functionalities was achieved between coculture and sandwich culture with Matrigel, in the presence and absence of direct oxygenation. A complete double-layered structure of functional liver cells with vertical contact between hepatocytes and TMNK-1 was successfully constructed in the coculture with direct oxygen supply and was well-maintained for 14 days. The hepatocytes in this hierarchical culture exhibited improved survival, functional bile canaliculi formation, cellular level polarization and maintenance of metabolic activities including Cyp1A1/2 activity and albumin production. By contrast, the two cell populations formed discontinuous monolayers on the same surfaces in the non-oxygen-permeable cultures. These results demonstrate that (i) the direct oxygenation through the PDMS membranes enables very simple formation of a hierarchical structure consisting of a hepatocyte layer and a layer of TMNK-1 and (ii) we may include other non-parenchymal cells in this format easily, which can be widely applicable to other epithelial organs.

Outcomes of physiological and active third stage labour care amongst women in New Zealand.

PubMed

Dixon, Lesley; Tracy, Sally K; Guilliland, Karen; Fletcher, Lynn; Hendry, Chris; Pairman, Sally

2013-01-01

during the third stage of labour there are two approaches for care provision - active management or physiological (expectant) care. The aim of this research was to describe, analyse and compare the midwifery care pathway and outcomes provided to a selected cohort of New Zealand women during the third stage of labour between the years 2004 and 2008. These women received continuity of care from a midwife Lead Maternity Carer and gave birth in a variety of birth settings (home, primary, secondary and tertiary maternity units). retrospective aggregated clinical information was extracted from the New Zealand College of Midwives research database. Factors such as type of third stage labour care provided; estimated blood loss; rate of treatment (separate to prophylaxis) with a uterotonic; and placental condition were compared amongst women who had a spontaneous onset of labour and no further assistance during the labour and birth. The results were adjusted for age, ethnicity, parity, place of birth, length of labour and weight of the baby. the rates of physiological third stage care (expectant) and active management within the cohort were similar (48.1% vs. 51.9%). Women who had active management had a higher risk of a blood loss of more than 500mL, the risk was 2.761 when a woman was actively managed (95% CI: 2.441-3.122) when compared to physiological management. Women giving birth at home and in a primary unit were more likely to have physiological management. A longer labour and higher parity increased the odds of having active management. Manual removal of the placenta was more likely with active management (0.7% active management - 0.2% physiological p<0.0001). For women who were given a uterotonic drug as a treatment rather than prophylaxis a postpartum haemorrhage of more than 500mL was twice as likely in the actively managed group compared to the physiological managed group (6.9% vs. 3.7%, RR 0.54, CI: 0.5, 0.6). the use of physiological care during the third stage of labour should be considered and supported for women who are healthy and have had a spontaneous labour and birth regardless of birth place setting. Further research should determine whether the use of a uterotonic as a treatment in the first instance may be more effective than as a treatment following initial exposure prophylactically. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Impact of Protein Phosphorylation on Chlamydial Physiology

PubMed Central

Claywell, Ja E.; Matschke, Lea M.; Fisher, Derek J.

2016-01-01

Chlamydia are Gram negative bacterial pathogens responsible for disease in humans and economically important domesticated animals. As obligate intracellular bacteria, they must gain entry into a host cell where they propagate within a parasitophorous organelle that serves as an interactive interface between the bacterium and the host. Nutrient acquisition, growth, and evasion of host defense mechanisms occur from this location. In addition to these cellular and bacterial dynamics, Chlamydia differentiate between two morphologically distinct forms, the elementary body and reticulate body, that are optimized for either extracellular or intracellular survival, respectively. The mechanisms regulating and mediating these diverse physiological events remain largely unknown. Reversible phosphorylation, including classical two-component signaling systems, partner switching mechanisms, and the more recently appreciated bacterial Ser/Thr/Tyr kinases and phosphatases, has gained increasing attention for its role in regulating important physiological processes in bacteria including metabolism, development, and virulence. Phosphorylation modulates these events via rapid and reversible modification of protein substrates leading to changes in enzyme activity, protein oligomerization, cell signaling, and protein localization. The characterization of several conserved chlamydial protein kinases and phosphatases along with phosphoproteome analysis suggest that Chlamydia are capable of global and growth stage-specific protein phosphorylation. This mini review will highlight the current knowledge of protein phosphorylation in Chlamydia and its potential role in chlamydial physiology and, consequently, virulence. Comparisons with other minimal genome intracellular bacterial pathogens also will be addressed with the aim of illustrating the importance of this understudied regulatory mechanism on pathogenesis and the principle questions that remain unanswered. PMID:28066729

A day of immersive physiology experiments increases knowledge and excitement towards physiology and scientific careers in Native American students.

PubMed

Becker, Bryan K; Schiller, Alicia M; Zucker, Irving H; Eager, Eric A; Bronner, Liliana P; Godfrey, Maurice

2017-03-01

Underserved minority groups are disproportionately absent from the pursuit of careers in science, technology, engineering, and mathematics (STEM) fields. One such underserved population, Native Americans, are particularly underrepresented in STEM fields. Although recent advocacy and outreach designed toward increasing minority involvement in health care-related occupations have been mostly successful, little is known about the efficacy of outreach programs in increasing minority enthusiasm toward careers in traditional scientific professions. Furthermore, very little is known about outreach among Native American schools toward increasing involvement in STEM. We collaborated with tribal middle and high schools in South Dakota and Nebraska through a National Institutes of Health Science Education Partnership Award to hold a day-long physiology, activity-based event to increase both understanding of physiology and enthusiasm to scientific careers. We recruited volunteer biomedical scientists and trainees from the University of Nebraska Medical Center, Nebraska Wesleyan University, and University of South Dakota. To evaluate the effectiveness of the day of activities, 224 of the ~275-300 participating students completed both a pre- and postevent evaluation assessment. We observed increases in both students self-perceived knowledge of physiology and enthusiasm toward scientific career opportunities after the day of outreach activities. We conclude that activity-based learning opportunities in underserved populations are effective in increasing both knowledge of science and interest in scientific careers. Copyright © 2017 the American Physiological Society.

Physiological β-catenin signaling controls self-renewal networks and generation of stem-like cells from nasopharyngeal carcinoma.

PubMed

Cheng, Yue; Cheung, Arthur Kwok Leung; Ko, Josephine Mun Yee; Phoon, Yee Peng; Chiu, Pui Man; Lo, Paulisally Hau Yi; Waterman, Marian L; Lung, Maria Li

2013-09-27

A few reports suggested that low levels of Wnt signaling might drive cell reprogramming, but these studies could not establish a clear relationship between Wnt signaling and self-renewal networks. There are ongoing debates as to whether and how the Wnt/β-catenin signaling is involved in the control of pluripotency gene networks. Additionally, whether physiological β-catenin signaling generates stem-like cells through interactions with other pathways is as yet unclear. The nasopharyngeal carcinoma HONE1 cells have low expression of β-catenin and wild-type expression of p53, which provided a possibility to study regulatory mechanism of stemness networks induced by physiological levels of Wnt signaling in these cells. Introduction of increased β-catenin signaling, haploid expression of β-catenin under control by its natural regulators in transferred chromosome 3, resulted in activation of Wnt/β-catenin networks and dedifferentiation in HONE1 hybrid cell lines, but not in esophageal carcinoma SLMT1 hybrid cells that had high levels of endogenous β-catenin expression. HONE1 hybrid cells displayed stem cell-like properties, including enhancement of CD24(+) and CD44(+) populations and generation of spheres that were not observed in parental HONE1 cells. Signaling cascades were detected in HONE1 hybrid cells, including activation of p53- and RB1-mediated tumor suppressor pathways, up-regulation of Nanog-, Oct4-, Sox2-, and Klf4-mediated pluripotency networks, and altered E-cadherin expression in both in vitro and in vivo assays. qPCR array analyses further revealed interactions of physiological Wnt/β-catenin signaling with other pathways such as epithelial-mesenchymal transition, TGF-β, Activin, BMPR, FGFR2, and LIFR- and IL6ST-mediated cell self-renewal networks. Using β-catenin shRNA inhibitory assays, a dominant role for β-catenin in these cellular network activities was observed. The expression of cell surface markers such as CD9, CD24, CD44, CD90, and CD133 in generated spheres was progressively up-regulated compared to HONE1 hybrid cells. Thirty-four up-regulated components of the Wnt pathway were identified in these spheres. Wnt/β-catenin signaling regulates self-renewal networks and plays a central role in the control of pluripotency genes, tumor suppressive pathways and expression of cancer stem cell markers. This current study provides a novel platform to investigate the interaction of physiological Wnt/β-catenin signaling with stemness transition networks.

Investigating the physiology of brain activation with MRI

NASA Astrophysics Data System (ADS)

Buxton, Richard B.; Uludag, Kamil; Dubowitz, David J.

2004-04-01

Functional magnetic resonance imaging (fMRI) has become a powerful tool for investigating the working human brain based on the blood oxygenation level dependent (BOLD) effect on the MR signal. However, despite the widespread use of fMRI techniques for mapping brain activation, the basic physiological mechanisms underlying the observed signal changes are still poorly understood. Arterial spin labeling (ASL) techniques, which measure cerebral blood flow (CBF) and the BOLD effect simultaneously, provide a useful tool for investigating these physiological questions. In this paper, recent results of studies manipulating the baseline CBF both pharmacologically and physiologically will be discussed. These data are consistent with a feed-forward mechanism of neurovascular coupling, and suggest that the CBF change itself may be a more robust reflection of neural activity changes than the BOLD effect. Consistent with these data, a new thermodynamic hypothesis is proposed for the physiological function of CBF regulation: maintenance of the [O2]/[CO2] concentration ratio at the mitochondria in order to preserve the free energy available from oxidative metabolism. A kinetic model based on this hypothesis provides a reasonable quantitative description of the CBF changes associated with neural activity and altered blood gases (CO2 and O2).

Characterizing endophytic competence and plant growth promotion of bacterial endophytes inhabiting the seed endosphere of Rice.

PubMed

Walitang, Denver I; Kim, Kiyoon; Madhaiyan, Munusamy; Kim, Young Kee; Kang, Yeongyeong; Sa, Tongmin

2017-10-26

Rice (Oryza sativa L. ssp. indica) seeds as plant microbiome present both an opportunity and a challenge to colonizing bacterial community living in close association with plants. Nevertheless, the roles and activities of bacterial endophytes remain largely unexplored and insights into plant-microbe interaction are compounded by its complexity. In this study, putative functions or physiological properties associated with bacterial endophytic nature were assessed. Also, endophytic roles in plant growth and germination that may allow them to be selectively chosen by plants were also studied. The cultivable seed endophytes were dominated by Proteobacteria particularly class Gammaproteobacteria. Highly identical type strains were isolated from the seed endosphere regardless of the rice host's physiological tolerance to salinity. Among the type strains, Flavobacterium sp., Microbacterium sp. and Xanthomonas sp. were isolated from the salt-sensitive and salt-tolerant cultivars. PCA-Biplot ordination also showed that specific type strains isolated from different rice cultivars have distinguishing similar characteristics. Flavobacterium sp. strains are phosphate solubilizers and indole-3-acetic acid producers with high tolerance to salinity and osmotic stress. Pseudomonas strains are characterized as high siderophore producers while Microbacterium sp. and Xanthomonas sp. strains have very high pectinase and cellulase activity. Among the physiological traits of the seed endophytes, bacterial pectinase and cellulase activity are positively correlated as well as salt and osmotic tolerance. Overall characterization shows that majority of the isolates could survive in 4-8% salt concentration as well as in 0.6 M and 1.2 M sucrose solution. The activities of catalase, pectinase and cellulase were also observed in almost all of the isolates indicating the importance of these characteristics for survival and colonization into the seed endosphere. Seed bacterial endophytes also showed promising plant growth promoting activities including hormone modulation, nitrogen fixation, siderophore production and phosphate solubilization. Though many of the isolates possess similar PGP and endophytic physiological traits, this study shows some prominent and distinguishing traits among bacterial groups indicating key determinants for their success as endophytes in the rice seed endosphere. Rice seeds are also inhabited by bacterial endophytes that promote growth during early seedling development.

'Multimorbidity' as the manifestation of network disturbances.

PubMed

Sturmberg, Joachim P; Bennett, Jeanette M; Martin, Carmel M; Picard, Martin

2017-02-01

We argue that 'multimorbidity' is the manifestation of interconnected physiological network processes within an individual in his or her socio-cultural environment. Networks include genomic, metabolomic, proteomic, neuroendocrine, immune and mitochondrial bioenergetic elements, as well as social, environmental and health care networks. Stress systems and other physiological mechanisms create feedback loops that integrate and regulate internal networks within the individual. Minor (e.g. daily hassles) and major (e.g. trauma) stressful life experiences perturb internal and social networks resulting in physiological instability with changes ranging from improved resilience to unhealthy adaptation and 'clinical disease'. Understanding 'multimorbidity' as a complex adaptive systems response to biobehavioural and socio-environmental networks is essential. Thus, designing integrative care delivery approaches that more adequately address the underlying disease processes as the manifestation of a state of physiological dysregulation is essential. This framework can shape care delivery approaches to meet the individual's care needs in the context of his or her underlying illness experience. It recognizes 'multimorbidity' and its symptoms as the end product of complex physiological processes, namely, stress activation and mitochondrial energetics, and suggests new opportunities for treatment and prevention. The future of 'multimorbidity' management might become much more discerning by combining the balancing of physiological dysregulation with targeted personalized biotechnology interventions such as small molecule therapeutics targeting specific cellular components of the stress response, with community-embedded interventions that involve addressing psycho-socio-cultural impediments that would aim to strengthen personal/social resilience and enhance social capital. © 2016 John Wiley & Sons, Ltd.

Hyperventilation in anticipatory music performance anxiety.

PubMed

Studer, Regina Katharina; Danuser, Brigitta; Hildebrandt, Horst; Arial, Marc; Wild, Pascal; Gomez, Patrick

2012-09-01

Self-report studies have shown an association between music performance anxiety (MPA) and hyperventilation complaints. However, hyperventilation was never assessed physiologically in MPA. This study investigated the self-reported affective experience, self-reported physiological symptoms, and cardiorespiratory variables including partial pressure of end-tidal CO(2) (Petco(2)), which is an indicator for hyperventilation, in 67 music students before a private and a public performance. The response coherence between these response domains was also investigated. From the private to the public session, the intensity of all self-report variables increased (all p values < .001). As predicted, the higher the musician's usual MPA level, the larger were these increases (p values < .10). With the exception of Petco(2), the main cardiorespiratory variables also increased from the private to the public session (p values < .05). These increases were not modulated by the usual MPA level (p values > .10). Petco(2) showed a unique response pattern reflected by an MPA-by-session interaction (p < .01): it increased from the private to the public session for musicians with low MPA levels and decreased for musicians with high MPA levels. Self-reported physiological symptoms were related to the self-reported affective experience (p values < .05) rather than to physiological measures (p values > .17). These findings show for the first time how respiration is stimulated before a public performance in music students with different MPA levels. The hypothesis of a hyperventilation tendency in high-performance-anxious musicians is supported. The response coherence between physiological symptoms and physiological activation is weak.

Digital chalk-talk videos improve knowledge and satisfaction in renal physiology.

PubMed

Roberts, John K; Chudgar, Saumil M; Engle, Deborah; McClain, Elizabeth K; Jakoi, Emma; Berkoben, Michael; Lehrich, Ruediger W

2018-03-01

The authors began a curriculum reform project to improve the experience in a Renal Physiology course for first-year medical students. Taking into account both the variety of learning preferences among students and the benefits of student autonomy, the authors hypothesized that adding digital chalk-talk videos to lecture notes and live lectures would improve student knowledge, course satisfaction, and engagement. The authors measured performance on the renal physiology exam before (the traditional curriculum) and for 2 yr after implementation of the new curriculum. During the traditional and subsequent years, students took a Q-sort survey before and after the Renal Physiology course. Satisfaction was assessed based on ranked statements in the Q sort, as well as through qualitative analysis of student commentary. Compared with the traditional curriculum, mean scores on the renal physiology final exam were higher after implementation of the new curriculum: 65.3 vs. 74.4 ( P < 0.001) with year 1 and 65.3 vs. 79.4 ( P < 0.001) in the second year. After the new curriculum, students were more likely to agree with the statement, "I wish other courses were taught like this one." Qualitative analysis revealed how the video-based curriculum improved student engagement and satisfaction. Adding digital chalk-talk videos to a traditional Renal Physiology course that included active learning led to improved exam performance and high levels of student satisfaction. Other preclinical courses in medical school may benefit from such an intervention.

Males and females show differential brain activation to taste when hungry and sated in gustatory and reward areas.

PubMed

Haase, Lori; Green, Erin; Murphy, Claire

2011-10-01

Although males and females differ in eating behavior and prevalence rates for eating disorders and obesity, little is known about gender differences in cortical activation to pleasant and unpleasant pure tastes during the physiological states of hunger and satiety. Twenty-one healthy young adults (12 females and 9 males) underwent two functional magnetic resonance imaging scans. Using four pure tastants of differing qualities (i.e., salty, sour, bitter, sweet), the present study examined gender differences in fMRI activation during two motivational states (hunger and satiety). There was greater change in fMRI activation from hunger to satiety in males than females in response to all tastes within the middle frontal gyrus (BA 10), insula, and cerebellum. Males also had greater change in activation from hunger to satiety, relative to females, in limbic regions including dorsal striatum, amygdala, parahippocampal gyrus, and posterior and anterior cingulate; however, activation was stimulus dependent, despite equivalent ratings in perceived pleasantness and intensity. Interestingly, males and females showed significant change from hunger to satiety in response to citric acid, suggesting that in addition to gender and physiological condition, stimulus quality is an important factor in taste fMRI activation. These gender differences may have implications for the pathophysiology of eating disorders and obesity. Copyright © 2011 Elsevier Ltd. All rights reserved.

Can the behaviour of threespine stickleback parasitized with Schistocephalus solidus be replicated by manipulating host physiology?

PubMed

Grécias, Lucie; Hébert, François Olivier; Berger, Chloé Suzanne; Barber, Iain; Aubin-Horth, Nadia

2017-01-15

Sticklebacks infected by the parasitic flatworm Schistocephalus solidus show dramatic changes in phenotype, including a loss of species-typical behavioural responses to predators. The timing of host behaviour change coincides with the development of infectivity of the parasite to the final host (a piscivorous bird), making it an ideal model for studying the mechanisms of infection-induced behavioural modification. However, whether the loss of host anti-predator behaviour results from direct manipulation by the parasite, or is a by-product (e.g. host immune response) or side effect of infection (e.g. energetic loss), remains controversial. To understand the physiological mechanisms that generate these behavioural changes, we quantified the behavioural profiles of experimentally infected fish and attempted to replicate these in non-parasitized fish by exposing them to treatments including immunity activation and fasting, or by pharmacologically inhibiting the stress axis. All fish were screened for the following behaviours: activity, water depth preference, sociability, phototaxis, anti-predator response and latency to feed. We were able to change individual behaviours with certain treatments. Our results suggest that the impact of S. solidus on the stickleback might be of a multifactorial nature. The behaviour changes observed in infected fish might result from the combined effects of modifying the serotonergic axis, lack of energy and activation of the immune system. © 2017. Published by The Company of Biologists Ltd.

Analysis of natural variation in bermudagrass (Cynodon dactylon) reveals physiological responses underlying drought tolerance.

PubMed

Shi, Haitao; Wang, Yanping; Cheng, Zhangmin; Ye, Tiantian; Chan, Zhulong

2012-01-01

Bermudagrass (Cynodon dactylon) is a widely used warm-season turfgrass and one of the most drought tolerant species. Dissecting the natural variation in drought tolerance and physiological responses will bring us powerful basis and novel insight for plant breeding. In the present study, we evaluated the natural variation of drought tolerance among nine bermudagrass varieties by measuring physiological responses after drought stress treatment through withholding water. Three groups differing in drought tolerance were identified, including two tolerant, five moderately tolerant and two susceptible varieties. Under drought stress condition, drought sensitive variety (Yukon) showed relative higher water loss, more severe cell membrane damage (EL), and more accumulation of hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), while drought tolerant variety (Tifgreen) exhibited significantly higher antioxidant enzymes activities. Further results indicated that drought induced cell injury in different varieties (Yukon, SR9554 and Tifgreen) exhibited liner correlation with leaf water content (LWC), H₂O₂ content, MDA content and antioxidant enzyme activities. Additionally, Tifgreen plants had significantly higher levels of osmolytes (proline level and soluble sugars) when compared with Yukon and SR9554 under drought stress condition. Taken together, our results indicated that natural variation of drought stress tolerance in bermudagrass varieties might be largely related to the induced changes of water status, osmolyte accumulation and antioxidant defense system.

Effects of Social Exclusion on Cardiovascular and Affective Reactivity to a Socially Evaluative Stressor.

PubMed

Williamson, Timothy J; Thomas, KaMala S; Eisenberger, Naomi I; Stanton, Annette L

2018-04-03

Socially disconnected individuals have worse health than those who feel socially connected. The mechanisms through which social disconnection influences physiological and psychological outcomes warrant study. The current study tested whether experimental manipulations of social exclusion, relative to inclusion, influenced subsequent cardiovascular (CV) and affective reactivity to socially evaluative stress. Young adults (N = 81) were assigned through block randomization to experience either social exclusion or inclusion, using a standardized computer-based task (Cyberball). Immediately after exposure to Cyberball, participants either underwent a socially evaluative stressor or an active control task, based on block randomization. Physiological activity (systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR)) and state anxiety were assessed throughout the experiment. Excluded participants evidenced a significant increase in cardiovascular and affective responses to a socially evaluative stressor. Included participants who underwent the stressor evidenced similar increases in anxiety, but systolic blood pressure, diastolic blood pressure, and heart rate did not change significantly in response to the stressor. Results contribute to the understanding of physiological consequences of social exclusion. Further investigation is needed to test whether social inclusion can buffer CV stress reactivity, which would carry implications for how positive social factors may protect against the harmful effects of stress.

Biophysical and physiological origins of blood oxygenation level-dependent fMRI signals.

PubMed

Kim, Seong-Gi; Ogawa, Seiji

2012-07-01

After its discovery in 1990, blood oxygenation level-dependent (BOLD) contrast in functional magnetic resonance imaging (fMRI) has been widely used to map brain activation in humans and animals. Since fMRI relies on signal changes induced by neural activity, its signal source can be complex and is also dependent on imaging parameters and techniques. In this review, we identify and describe the origins of BOLD fMRI signals, including the topics of (1) effects of spin density, volume fraction, inflow, perfusion, and susceptibility as potential contributors to BOLD fMRI, (2) intravascular and extravascular contributions to conventional gradient-echo and spin-echo BOLD fMRI, (3) spatial specificity of hemodynamic-based fMRI related to vascular architecture and intrinsic hemodynamic responses, (4) BOLD signal contributions from functional changes in cerebral blood flow (CBF), cerebral blood volume (CBV), and cerebral metabolic rate of O(2) utilization (CMRO(2)), (5) dynamic responses of BOLD, CBF, CMRO(2), and arterial and venous CBV, (6) potential sources of initial BOLD dips, poststimulus BOLD undershoots, and prolonged negative BOLD fMRI signals, (7) dependence of stimulus-evoked BOLD signals on baseline physiology, and (8) basis of resting-state BOLD fluctuations. These discussions are highly relevant to interpreting BOLD fMRI signals as physiological means.

Biophysical and physiological origins of blood oxygenation level-dependent fMRI signals

PubMed Central

Kim, Seong-Gi; Ogawa, Seiji

2012-01-01

After its discovery in 1990, blood oxygenation level-dependent (BOLD) contrast in functional magnetic resonance imaging (fMRI) has been widely used to map brain activation in humans and animals. Since fMRI relies on signal changes induced by neural activity, its signal source can be complex and is also dependent on imaging parameters and techniques. In this review, we identify and describe the origins of BOLD fMRI signals, including the topics of (1) effects of spin density, volume fraction, inflow, perfusion, and susceptibility as potential contributors to BOLD fMRI, (2) intravascular and extravascular contributions to conventional gradient-echo and spin-echo BOLD fMRI, (3) spatial specificity of hemodynamic-based fMRI related to vascular architecture and intrinsic hemodynamic responses, (4) BOLD signal contributions from functional changes in cerebral blood flow (CBF), cerebral blood volume (CBV), and cerebral metabolic rate of O2 utilization (CMRO2), (5) dynamic responses of BOLD, CBF, CMRO2, and arterial and venous CBV, (6) potential sources of initial BOLD dips, poststimulus BOLD undershoots, and prolonged negative BOLD fMRI signals, (7) dependence of stimulus-evoked BOLD signals on baseline physiology, and (8) basis of resting-state BOLD fluctuations. These discussions are highly relevant to interpreting BOLD fMRI signals as physiological means. PMID:22395207

Development of a network system combined with ambulatory and non-conscious physiological measurements for supporting challenged kids - a new proposal of a gait monitoring system for use in rehabilitation.

PubMed

Motoi, Kosuke; Oyama, Takanobu; Tanaka, Naoto; Yuji, Tadahiko; Higashi, Yuji; Sagawa, Koichi; Fujimoto, Toshiro; Yamakoshi, Ken-Ichi

2013-01-01

Various physiological measurement techniques have been developed to support healthcare and daily living of adult including elderly. However, in light of the rapid growth of the declining birth rate, promotion in care and life support for children are not enough. Especially in rehabilitation for disabled children, i.e., challenged kids, it is important for therapist to evaluate the efficacy of rehabilitation and the health condition. Share of these information with educational, welfare, and government institutions are also needed for accurate life support. Therefore, the quantitative data of the activities and daily health status are helpful. From these viewpoints, we are developing a new network system for monitoring the activities and the health status of children using ambulatory and non-conscious physiological measurements as well as data browse at anytime and anywhere. Firstly, we propose a wearable gait monitoring system to support evaluation for the efficacy of rehabilitation. In this study, the present system can successfully detect the characteristics of postural changes in children with disorder of movement, demonstrating its usefulness and availability to the evaluation for the effect of the brace attached to the subject's lower limb.

A putative low-molecular-mass penicillin-binding protein (PBP) of Mycobacterium smegmatis exhibits prominent physiological characteristics of DD-carboxypeptidase and beta-lactamase.

PubMed

Bansal, Ankita; Kar, Debasish; Murugan, Rajagopal A; Mallick, Sathi; Dutta, Mouparna; Pandey, Satya Deo; Chowdhury, Chiranjit; Ghosh, Anindya S

2015-05-01

DD-carboxypeptidases (DD-CPases) are low-molecular-mass (LMM) penicillin-binding proteins (PBPs) that are mainly involved in peptidoglycan remodelling, but little is known about the dd-CPases of mycobacteria. In this study, a putative DD-CPase of Mycobacterium smegmatis, MSMEG_2433 is characterized. The gene for the membrane-bound form of MSMEG_2433 was cloned and expressed in Escherichia coli in its active form, as revealed by its ability to bind to the Bocillin-FL (fluorescent penicillin). Interestingly, in vivo expression of MSMEG_2433 could restore the cell shape oddities of the septuple PBP mutant of E. coli, which was a prominent physiological characteristic of DD-CPases. Moreover, expression of MSMEG_2433 in trans elevated beta-lactam resistance in PBP deletion mutants (ΔdacAdacC) of E. coli, strengthening its physiology as a dd-CPase. To confirm the biochemical reason behind such physiological behaviours, a soluble form of MSMEG_2433 (sMSMEG_2433) was created, expressed and purified. In agreement with the observed physiological phenomena, sMSMEG_2433 exhibited DD-CPase activity against artificial and peptidoglycan-mimetic DD-CPase substrates. To our surprise, enzymic analyses of MSMEG_2433 revealed efficient deacylation for beta-lactam substrates at physiological pH, which is a unique characteristic of beta-lactamases. In addition to the MSMEG_2433 active site that favours dd-CPase activity, in silico analyses also predicted the presence of an omega-loop-like region in MSMEG_2433, which is an important determinant of its beta-lactamase activity. Based on the in vitro, in vivo and in silico studies, we conclude that MSMEG_2433 is a dual enzyme, possessing both DD-CPase and beta-lactamase activities. © 2015 The Authors.

Src is required for migration, phagocytosis, and interferon beta production in Toll-like receptor-engaged macrophages.

PubMed

Maa, Ming-Chei; Leu, Tzeng-Horng

2016-06-01

As an evolutionarily conserved mechanism, innate immunity controls self-nonself discrimination to protect a host from invasive pathogens. Macrophages are major participants of the innate immune system. Through the activation of diverse Toll-like receptors (TLRs), macrophages are triggered to initiate a variety of functions including locomotion, phagocytosis, and secretion of cytokines that requires the participation of tyrosine kinases. Fgr, Hck, and Lyn are myeloid-specific Src family kinases. Despite their constitutively high expression in macrophages, their absence does not impair LPS responsiveness. In contrast, Src, a barely detectable tyrosine kinase in resting macrophages, becomes greatly inducible in response to TLR engagement, implicating its role in macrophage activation. Indeed, silencing Src suppresses the activated TLR-mediated migration, phagocytosis, and interferon-beta (IFN-β) secretion in macrophages. And these physiological defects can be restored by the introduction of siRNA-resistant Src. Notably, the elevated expression and activity of Src is inducible nitric oxide synthase (iNOS)-dependent. Due to (1) iNOS being a NF-κB target, which can be induced by various TLR ligands, (2) Src can mediate NF-κB activation, therefore, there ought to exist a loop of signal amplification that regulates macrophage physiology in response to the engagement of TLRs.

Social information changes stress hormone receptor expression in the songbird brain.

PubMed

Cornelius, Jamie M; Perreau, Gillian; Bishop, Valerie R; Krause, Jesse S; Smith, Rachael; Hahn, Thomas P; Meddle, Simone L

2018-01-01

Social information is used by many vertebrate taxa to inform decision-making, including resource-mediated movements, yet the mechanisms whereby social information is integrated physiologically to affect such decisions remain unknown. Social information is known to influence the physiological response to food reduction in captive songbirds. Red crossbills (Loxia curvirostra) that were food reduced for several days showed significant elevations in circulating corticosterone (a "stress" hormone often responsive to food limitation) only if their neighbors were similarly food restricted. Physiological responses to glucocorticoid hormones are enacted through two receptors that may be expressed differentially in target tissues. Therefore, we investigated the influence of social information on the expression of the mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) mRNA in captive red crossbill brains. Although the role of MR and GR in the response to social information may be highly complex, we specifically predicted social information from food-restricted individuals would reduce MR and GR expression in two brain regions known to regulate hypothalamic-pituitary-adrenal (HPA) activity - given that reduced receptor expression may lessen the efficacy of negative feedback and release inhibitory tone on the HPA. Our results support these predictions - offering one potential mechanism whereby social cues could increase or sustain HPA-activity during stress. The data further suggest different mechanisms by which metabolic stress versus social information influence HPA activity and behavioral outcomes. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Developing and evaluating effective bioscience learning activities for nursing students.

PubMed

Salvage-Jones, Judith; Hamill, Jessie; Todorovic, Michael; Barton, Matthew J; Johnston, Amy N B

2016-07-01

Effective engagement of nursing students in the study of biosciences remains a challenge for many tertiary institutes. In this study we attempted to implement and then evaluate a simple hands-on intervention, consisting of a series of hands-on games and puzzles, to increase nursing student engagement with core concepts and anatomical learning involved in clinical anatomy and physiology. The study used a quazi-experimental longitudinal before and after design, to explore the effect of a learning intervention on student performance. Set across three different campuses of the same University, it included 1320 first year undergraduate nursing students from 2013 to 2014 who were studying Anatomy and Physiology. Students were exposed to the interventions or not, and concomitant academic performance, weekly quiz scores, performance in fortnightly worksheets and, across the semester, exam performance were compared. The results show that while the intervention appeared to increase academic performance in students on one campus (2013) compared to the other two, this difference was not sustained into 2014 when a bigger cohort was examined. Despite significant subjective student satisfaction and enthusiasm about these learning and teaching interventions, the data does not support the capacity of these activities to enhance student academic performance. Tertiary entrance scores, being a non-native English speakers and socio-economic status all had a bigger impact on student performance than engagement with fun anatomy and physiology activities. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Comparative analysis of international standards for the fatigue testing of posterior spinal fixation systems.

PubMed

Villa, Tomaso; La Barbera, Luigi; Galbusera, Fabio

2014-04-01

Preclinical evaluation of the long-term reliability of devices for lumbar fixation is a mandatory activity before they are put into market. The experimental setups are described in two different standards edited by the International Organization for Standardization (ISO) and the American Society for Testing Materials (ASTM), but the evaluation of the suitability of such tests to simulate the actual loading with in vivo situations has never been performed. To calculate through finite element (FE) simulations the stress in the rods of the fixator when subjected to ASTM and ISO standards. To compare the calculated stresses arising in the same fixator once it has been virtually mounted in a physiological environment and loaded with physiological forces and moments. FE simulations and validation experimental tests. FE models of the ISO and ASTM setups were created to conduct simulations of the tests prescribed by standards and calculate stresses in the rods. Validation of the simulations were performed through experimental tests; the same fixator was virtually mounted in an L2-L4 FE model of the lumbar spine and stresses in the rods were calculated when the spine was subjected to physiological forces and moments. The comparison between FE simulations and experimental tests showed good agreement between results obtained using the two methodologies, thus confirming the suitability of the FE method to evaluate stresses in the device in different loading situations. The usage of a physiological load with ASTM standard is impossible due to the extreme severity of the ASTM configuration; in this circumstance, the presence of an anterior support is suggested. Also, ISO prescriptions, although the choice of the setup correctly simulates the mechanical contribution of the discs, seem to overstress the device as compared with a physiological loading condition. Some daily activities, other than walking, can induce a further state of stress in the device that should be taken into account in setting up new experimental procedures. ISO standard loading prescriptions seems to be more severe than the expected physiological ones. The ASTM standard should be completed by including some anterior supporting device and declaring the value of the load to be imposed. Moreover, a further enhancement of standards would be simulating other movements representative of daily activities different from walking. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

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.

Physiological and lavage fluid cytological and biochemical endpoints of toxicity in the rat

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

Lehnert, B.E.

1992-01-01

Exposure of the respiratory tract to toxic materials can result in a variety of physiologic disturbances that can serve as endpoints of toxicity. In addition to a brief review of commonly assessed physiologic endpoints, attention is given in the first component of this report to the use of both nose breathing and mouth'' breathing rats in toxicity studies that involve measurements of ventilatory functional changes in response to test atmospheres. Additionally, the usefulness of maximum oxygen consumption, or VO[sub 2max], as a physiologic endpoint of toxicity that uses exercising rats after exposure to test atmospheres is described, along with anmore » introduction to post-exposure exercise as an important behavioral activity that can markedly impact on the severity of acute lung injury caused by pneumoedematogenic materials. The second component of this report focuses on bronchoalveolar lavage and cytological and biochemical endpoints that can be assessed in investigations of the toxicities of test materials. As will be shown herein, some of the biochemical endpoints of toxicity, especially, can sensitively detect subtle injury to the lower respiratory tract that may escape detection by changes in some other conventional endpoints of toxicity, including lung gravimetric increases and histopathological alterations.« less

Physiological and lavage fluid cytological and biochemical endpoints of toxicity in the rat

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

Lehnert, B.E.

1992-12-31

Exposure of the respiratory tract to toxic materials can result in a variety of physiologic disturbances that can serve as endpoints of toxicity. In addition to a brief review of commonly assessed physiologic endpoints, attention is given in the first component of this report to the use of both nose breathing and ``mouth`` breathing rats in toxicity studies that involve measurements of ventilatory functional changes in response to test atmospheres. Additionally, the usefulness of maximum oxygen consumption, or VO{sub 2max}, as a physiologic endpoint of toxicity that uses exercising rats after exposure to test atmospheres is described, along with anmore » introduction to post-exposure exercise as an important behavioral activity that can markedly impact on the severity of acute lung injury caused by pneumoedematogenic materials. The second component of this report focuses on bronchoalveolar lavage and cytological and biochemical endpoints that can be assessed in investigations of the toxicities of test materials. As will be shown herein, some of the biochemical endpoints of toxicity, especially, can sensitively detect subtle injury to the lower respiratory tract that may escape detection by changes in some other conventional endpoints of toxicity, including lung gravimetric increases and histopathological alterations.« less

Physiologic correlates to background noise acceptance

NASA Astrophysics Data System (ADS)

Tampas, Joanna; Harkrider, Ashley; Nabelek, Anna

2004-05-01

Acceptance of background noise can be evaluated by having listeners indicate the highest background noise level (BNL) they are willing to accept while following the words of a story presented at their most comfortable listening level (MCL). The difference between the selected MCL and BNL is termed the acceptable noise level (ANL). One of the consistent findings in previous studies of ANL is large intersubject variability in acceptance of background noise. This variability is not related to age, gender, hearing sensitivity, personality, type of background noise, or speech perception in noise performance. The purpose of the current experiment was to determine if individual differences in physiological activity measured from the peripheral and central auditory systems of young female adults with normal hearing can account for the variability observed in ANL. Correlations between ANL and various physiological responses, including spontaneous, click-evoked, and distortion-product otoacoustic emissions, auditory brainstem and middle latency evoked potentials, and electroencephalography will be presented. Results may increase understanding of the regions of the auditory system that contribute to individual noise acceptance.

A systematic analysis of the PARP protein family identifies new functions critical for cell physiology

PubMed Central

Vyas, Sejal; Chesarone-Cataldo, Melissa; Todorova, Tanya; Huang, Yun-Han; Chang, Paul

2013-01-01

The poly(ADP-ribose) polymerase (PARP) family of proteins use NAD+ as their substrate to modify acceptor proteins with adenosine diphosphate-ribose (ADPr) modifications. The function of most PARPs under physiological conditions is unknown. Here, to better understand this protein family, we systematically analyze the cell cycle localization of each PARP and of poly(ADP-ribose), a product of PARP activity, then identify the knock-down phenotype of each protein and perform secondary assays to elucidate function. We show that most PARPs are cytoplasmic, identify cell cycle differences in the ratio of nuclear to cytoplasmic poly(ADP-ribose), and identify four phenotypic classes of PARP function. These include the regulation of membrane structures, cell viability, cell division, and the actin cytoskeleton. Further analysis of PARP14 shows that it is a component of focal adhesion complexes required for proper cell motility and focal adhesion function. In total, we show that PARP proteins are critical regulators of eukaryotic physiology. PMID:23917125

Store-operated Ca2+ entry in muscle physiology and diseases

PubMed Central

Pan, Zui; Brotto, Marco; Ma, Jianjie

2014-01-01

Ca2+ release from intracellular stores and influx from extracellular reservoir regulate a wide range of physiological functions including muscle contraction and rhythmic heartbeat. One of the most ubiquitous pathways involved in controlled Ca2+ influx into cells is store-operated Ca2+ entry (SOCE), which is activated by the reduction of Ca2+ concentration in the lumen of endoplasmic or sarcoplasmic reticulum (ER/SR). Although SOCE is pronounced in non-excitable cells, accumulating evidences highlight its presence and important roles in skeletal muscle and heart. Recent discovery of STIM proteins as ER/SR Ca2+ sensors and Orai proteins as Ca2+ channel pore forming unit expedited the mechanistic understanding of this pathway. This review focuses on current advances of SOCE components, regulation and physiologic and pathophysiologic roles in muscles. The specific property and the dysfunction of this pathway in muscle diseases, and new directions for future research in this rapidly growing field are discussed. [BMB Reports 2014; 47(2): 69-79] PMID:24411466

Impact of stressor exposure on the interplay between commensal microbiota and host inflammation.

PubMed

Galley, Jeffrey D; Bailey, Michael T

2014-01-01

Exposure to stressful stimuli results in the activation of multiple physiological processes aimed at maintaining homeostasis within the body. These physiological processes also have the capacity to influence the composition of microbial communities, and research now indicates that exposure to stressful stimuli leads to gut microbiota dysbiosis. While the relative abundance of many different bacterial types can be altered during stressor exposure, findings in nonhuman primates and laboratory rodents, as well as humans, indicate that bacteria in the genus Lactobacillus are consistently reduced in the gut during stress. The gut microbiota, including the lactobacilli, have many functions that enhance the health of the host. This review presents studies involving germfree and antibiotic treated mice, as well as mice given Lactobacillus spp. to prevent stressor-induced reductions in lactobacilli, to provide evidence that the microbiota contribute to stressor-induced immunomodulation, both in gut mucosa as well as in systemic compartments. This review will also discuss the evidence that commensal gut microbes have bidirectional effects on gastrointestinal physiology during stressor exposure.

BIOTEX--biosensing textiles for personalised healthcare management.

PubMed

Coyle, Shirley; Lau, King-Tong; Moyna, Niall; O'Gorman, Donal; Diamond, Dermot; Di Francesco, Fabio; Costanzo, Daniele; Salvo, Pietro; Trivella, Maria Giovanna; De Rossi, Danilo Emilio; Taccini, Nicola; Paradiso, Rita; Porchet, Jacque-André; Ridolfi, Andrea; Luprano, Jean; Chuzel, Cyril; Lanier, Thierry; Revol-Cavalier, Frdéric; Schoumacker, Sébastien; Mourier, Véronique; Chartier, Isabelle; Convert, Reynald; De-Moncuit, Henri; Bini, Christina

2010-03-01

Textile-based sensors offer an unobtrusive method of continually monitoring physiological parameters during daily activities. Chemical analysis of body fluids, noninvasively, is a novel and exciting area of personalized wearable healthcare systems. BIOTEX was an EU-funded project that aimed to develop textile sensors to measure physiological parameters and the chemical composition of body fluids, with a particular interest in sweat. A wearable sensing system has been developed that integrates a textile-based fluid handling system for sample collection and transport with a number of sensors including sodium, conductivity, and pH sensors. Sensors for sweat rate, ECG, respiration, and blood oxygenation were also developed. For the first time, it has been possible to monitor a number of physiological parameters together with sweat composition in real time. This has been carried out via a network of wearable sensors distributed around the body of a subject user. This has huge implications for the field of sports and human performance and opens a whole new field of research in the clinical setting.

Heart Activity and Autistic Behavior in Infants and Toddlers with Fragile X Syndrome

PubMed Central

Roberts, Jane E.; Tonnsen, Bridgette; Robinson, Ashley; Shinkareva, Svetlana V.

2014-01-01

The present study contrasted physiological arousal in infants and toddlers with fragile X syndrome to typically developing control participants and examined physiological predictors early in development to autism severity later in development in fragile X syndrome. Thirty-one males with fragile X syndrome (ages 8–40 months) and 25 age-matched control participants were included. The group with fragile X syndrome showed shorter interbeat intervals (IBIs), lower vagal tone (VT), and less modulation of IBI. Data suggested a nonlinear effect with IBI and autistic behavior; however, a linear effect with VT and autistic behavior emerged. These findings suggest that atypical physiological arousal emerges within the first year and predicts severity of autistic behavior in fragile X syndrome. These relationships are complex and dynamic, likely reflecting endogenous factors assumed to reflect atypical brain function secondary to reduced fragile X mental retardation protein. This research has important implications for the early identification and treatment of autistic behaviors in young children with fragile X syndrome. PMID:22515825

Exercise Responses after Inactivity

NASA Technical Reports Server (NTRS)

Convertino, Victor A.

1986-01-01

The exercise response after bed rest inactivity is a reduction in the physical work capacity and is manifested by significant decreases in oxygen uptake. The magnitude of decrease in maximal oxygen intake V(dot)O2max is related to the duration of confinement and the pre-bed-rest level of aerobic fitness; these relationships are relatively independent of age and gender. The reduced exercise performance and V(dot)O2max following bed rest are associated with various physiological adaptations including reductions in blood volume, submaximal and maximal stroke volume, maximal cardiac output, sceletal muscle tone and strength, and aerobic enzyme capacities, as well as increases in venous compliance and submaximal and maximal heart rate. This reduction in physiological capacity can be partially restored by specific countermeasures that provide regular muscular activity or orhtostatic stress or both during the bed rest exposure. The understanding of these physiological and physical responses to exercise following bed rest inactivity has important implications for the solution to safety and health problems that arise in clinical medicine, aerospace medicine, sedentary living, and aging.

Electrocardiographic consequences of a peripatetic lifestyle in gray wolves (Canis lupus)

USGS Publications Warehouse

Constable, Peter; Hinchcliff, Ken; Demma, Nick; Callahan, Margaret; Dale, Bruce W.; Fox, Kevin; Adams, Layne G.; Wack, Ray; Kramer, Lynn

1998-01-01

Cardiac chamber enlargement and hypertrophy are normal physiologic responses to repetitive endurance exercise activity in human beings and domestic dogs. Whether similar changes occur in wild animals as a consequence of increased activity is unknown. We found that free-ranging gray wolves (Canis lupus, n=11), the archetypical endurance athlete, have electrocardiographic evidence of cardiac chamber enlargement and hypertrophy relative to sedentary captive gray wolves (n=20), as demonstrated by significant increases in QRS duration, QT interval, and QT interval corrected for heart rate, a tendency towards increased Q, R, and S wave voltages in all leads, and a significant decrease in heart rate. We conclude that exercise activity level and therefore lifestyle affects physiologic variables in wild animals. An immediate consequence of this finding is that physiologic measurements obtained from a captive wild-animal population with reduced exercise activity level may not accurately reflect the normal physiologic state for free-ranging members of the same species.

The use of multiple indices of physiological activity to access viability in chlorine disinfected Escherichia coli O157:H7

NASA Technical Reports Server (NTRS)

Lisle, J. T.; Pyle, B. H.; McFeters, G. A.

1999-01-01

A suite of fluorescent intracellular stains and probes was used, in conjunction with viable plate counts, to assess the effect of chlorine disinfection on membrane potential (rhodamine 123; Rh123 and bis-(1,3-dibutylbarbituric acid) trimethine oxonol; DiBAC4(3)), membrane integrity (LIVE/DEAD BacLight kit), respiratory activity (5-cyano-2,3-ditolyl tetrazolium chloride; CTC) and substrate responsiveness (direct viable counts; DVC) in the commensal pathogen Escherichia coli O157:H7. After a 5 min exposure to the disinfectant, physiological indices were affected in the following order: viable plate counts > substrate responsiveness > membrane potential > respiratory activity > membrane integrity. In situ assessment of physiological activity by examining multiple targets, as demonstrated in this study, permits a more comprehensive determination of the site and extent of injury in bacterial cells following sublethal disinfection with chlorine. This approach to assessing altered bacterial physiology has application in various fields where detection of stressed bacteria is of interest.

Physiologic measures of sexual function in women: a review.

PubMed

Woodard, Terri L; Diamond, Michael P

2009-07-01

To review and describe physiologic measures of assessing sexual function in women. Literature review. Studies that use instruments designed to measure female sexual function. Women participating in studies of female sexual function. Various instruments that measure physiologic features of female sexual function. Appraisal of the various instruments, including their advantages and disadvantages. Many unique physiologic methods of evaluating female sexual function have been developed during the past four decades. Each method has its benefits and limitations. Many physiologic methods exist, but most are not well-validated. In addition there has been an inability to correlate most physiologic measures with subjective measures of sexual arousal. Furthermore, given the complex nature of the sexual response in women, physiologic measures should be considered in context of other data, including the history, physical examination, and validated questionnaires. Nonetheless, the existence of appropriate physiologic measures is vital to our understanding of female sexual function and dysfunction.

Nanochemistry of Protein-Based Delivery Agents

PubMed Central

Rajendran, Subin R. C. K.; Udenigwe, Chibuike C.; Yada, Rickey Y.

2016-01-01

The past decade has seen an increased interest in the conversion of food proteins into functional biomaterials, including their use for loading and delivery of physiologically active compounds such as nutraceuticals and pharmaceuticals. Proteins possess a competitive advantage over other platforms for the development of nanodelivery systems since they are biocompatible, amphipathic, and widely available. Proteins also have unique molecular structures and diverse functional groups that can be selectively modified to alter encapsulation and release properties. A number of physical and chemical methods have been used for preparing protein nanoformulations, each based on different underlying protein chemistry. This review focuses on the chemistry of the reorganization and/or modification of proteins into functional nanostructures for delivery, from the perspective of their preparation, functionality, stability and physiological behavior. PMID:27489854

Nanochemistry of protein-based delivery agents

NASA Astrophysics Data System (ADS)

Rajendran, Subin; Udenigwe, Chibuike; Yada, Rickey

2016-07-01

The past decade has seen an increased interest in the conversion of food proteins into functional biomaterials, including their use for loading and delivery of physiologically active compounds such as nutraceuticals and pharmaceuticals. Proteins possess a competitive advantage over other platforms for the development of nanodelivery systems since they are biocompatible, amphipathic, and widely available. Proteins also have unique molecular structures and diverse functional groups that can be selectively modified to alter encapsulation and release properties. A number of physical and chemical methods have been used for preparing protein nanoformulations, each based on different underlying protein chemistry. This review focuses on the chemistry of the reorganization and/or modification of proteins into functional nanostructures for delivery, from the perspective of their preparation, functionality, stability and physiological behavior.

Marine carotenoids: Bioactivities and potential benefits to human health.

PubMed

Chuyen, Hoang Van; Eun, Jong-Bang

2017-08-13

Among natural pigments, carotenoids play important roles in physiological functions. The characteristics of carotenoids and their effects on human health have been reported for a long time, but most studies have focused on carotenoids from vegetables, fruits, and other parts of higher plants. Few reports are available on carotenoids from marine sources, such as seaweeds, microalgae, and marine animals, which have attracted attention in recent decades. Hundreds of carotenoids have been identified and isolated from marine organisms and their beneficial physiological functions, such as anticancer, antiobesity, antidiabetic, anti-inflammatory, and cardioprotective activities have been reported. The purpose of this review is to discuss the literature on the beneficial bioactivities of some of the most abundant marine carotenoids, including fucoxanthin, astaxanthin, cantaxanthin, peridinin, fucoxanthinol, and halocynthiaxanthin.

Regulation of gonadotropin-releasing hormone neurons by glucose

PubMed Central

Roland, Alison V.; Moenter, Suzanne M.

2011-01-01

Reproduction is influenced by energy balance, but the physiological pathways mediating their relationship have not been fully elucidated. As the central regulators of fertility, gonadotropin-releasing hormone (GnRH) neurons integrate numerous physiological signals, including metabolic cues. Circulating glucose levels regulate GnRH release and may in part mediate the effects of negative energy balance on fertility. Existing evidence suggests that neural pathways originating in the hindbrain, as well as in the hypothalamic feeding nuclei, transmit information concerning glucose availability to GnRH neurons. Here we review recent evidence suggesting that GnRH neurons may directly sense changes in glucose availability by a mechanism involving adenosine monophosphate-activated protein kinase (AMPK). These findings expand our understanding of how metabolic signaling in the brain regulates reproduction. PMID:21855365

Perceived barriers and benefits to physical activity in colorectal cancer patients.

PubMed

Fisher, Abigail; Wardle, J; Beeken, R J; Croker, H; Williams, K; Grimmett, C

2016-02-01

There is emerging evidence for the benefits of physical activity (PA) post-diagnosis for colorectal cancer (CRC) survivors. However, population studies suggest activity levels in these patients are very low. Understanding perceived barriers and benefits to activity is a crucial step in designing effective interventions. Patients who were between 6 months and 5 years post-diagnosis with non-metastasised disease were identified from five London (UK) hospitals. Four hundred and ninety five completed a lifestyle survey that included open-ended questions on their perceived barriers (what things would stop you from doing more physical activity?) and benefits (what do you think you would gain from doing more physical activity?). Patients also recorded their activity levels using the Godin Leisure Time Exercise Questionnaire, along with sociodemographic and treatment variables. The most commonly reported barriers related to cancer and its treatments (e.g. fatigue). Age and mobility-related comorbidities (e.g. impaired mobility) were also frequently cited. Those who reported age and mobility as barriers, or reported any barrier, were significantly less active even after adjustment for multiple confounders. The most frequently reported benefits were physiological (e.g. improving health and fitness). Cancer-related benefits (such as prevention of recurrence) were rarely reported. Those perceiving physiological benefits or perceiving any benefits were more active in unadjusted models, but associations were not significant in adjusted models. We have identified important barriers and facilitators in CRC survivors that will aid in the design of theory-based PA interventions.

Student Responses to a Hands-On Kinesthetic Lecture Activity for Learning about the Oxygen Carrying Capacity of Blood

ERIC Educational Resources Information Center

Breckler, Jennifer; Yu, Justin R.

2011-01-01

This article describes a new hands-on, or "kinesthetic," activity for use in a physiology lecture hall to help students comprehend an important concept in cardiopulmonary physiology known as oxygen carrying capacity. One impetus for designing this activity was to address the needs of students who have a preference for kinesthetic…

Passive and Active Contributions to Glenohumeral Stability

DTIC Science & Technology

2001-10-25

physiological muscle contraction during free arm suspension and proportional to muscle physiological cross- sectional area [15] (Phys Load); ditto...of muscle contraction around GH-joint. Stiffness of the GH capsuloligamentous structure, which is the ratio of the force required to stretch the...important active stabilizer in inferior stability. Our results also suggested that low-level muscle activity (2% of maximum muscle contraction ), representing

A mobile system for assessment of physiological response to posture transitions.

PubMed

Jovanov, Emil; Milosevic, Mladen; Milenković, Aleksandar

2013-01-01

Posture changes initiate a dynamic physiological response that can be used as an indicator of the overall health status. We introduce an inconspicuous mobile wellness monitoring system (imWell) that continuously assesses the dynamic physiological response to posture transitions during activities of daily living. imWell utilizes a Zephyr BioHarness 3 physiological monitor that continually reports heart activity and physical activity via Bluetooth to a personal device (e.g. smartphone). The personal device processes the reported activity data in real-time to recognize posture transitions from the accelerometer data and to characterize dynamic heart response to posture changes. It annotates, logs, and uploads the heart activity data to our mHealth server. In this paper we present algorithms for detection of posture transitions and heart activity characterization during a sit-to-stand transition. The proposed system was tested on seven healthy subjects performing a predefined protocol. The total average and standard deviation for sit-to-stand transition time is 2.7 ± 0.69 s, resulting in the change of heart rate of 27.36 ± 9.30 bpm (from 63.3 ± 9.02 bpm to 90.66 ± 10.09 bpm).

Novel use of a noninvasive hemodynamic monitor in a personalized, active learning simulation.

PubMed

Zoller, Jonathan K; He, Jianghua; Ballew, Angela T; Orr, Walter N; Flynn, Brigid C

2017-06-01

The present study furthered the concept of simulation-based medical education by applying a personalized active learning component. We tested this novel approach utilizing a noninvasive hemodynamic monitor with the capability to measure and display in real time numerous hemodynamic parameters in the exercising participant. Changes in medical knowledge concerning physiology were examined with a pre-and posttest. Simply by observation of one's own hemodynamic variables, the understanding of complex physiological concepts was significantly enhanced. Copyright © 2017 the American Physiological Society.

The study of pain with blood oxygen level dependent functional magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Ibinson, James W.

Using blood oxygen level dependent functional magnetic resonance imaging (BOLD FMRI), the brain areas activated by pain were studied. These initial studies led to interesting new findings about the body's response to pain and to the refinement of one method used in FMRI analysis for correction of physiologic noise (signal fluctuations caused by the cyclic and non-cyclic changes in the cardiovascular and respiratory status of the body). In the first study, evidence was provided suggesting that the multiple painful stimulations used in typical pain FMRI block designs may cause attenuation over time of the BOLD signal within activated areas. The effect this may have on pain investigations using multiple tasks has not been previously investigated. The demonstrated BOLD attenuation seems unique to pain studies. Several possible explanations exist, but two of the most likely are neural activity modulation by descending pain inhibitory mechanisms and changing hemodynamics caused by a physiologic response to pain. The second study began the investigation of hemodynamics by monitoring the physiologic response to pain for eight subjects in two phases. Phase one used a combination of standard operating suite monitors and research equipment to characterizing the physiologic response to pain. Phase two collected magnetic resonance quantitative flow images during painful nerve stimulation to test for changes in global cerebral blood flow. It is well established that changes in respiration and global blood flow can affect the BOLD response, leading to the final investigation of this dissertation. The brain activation induced by pain for the same eight subjects used in the physiologic response experiments described above was then studied by BOLD FMRI. By including the respiration signal and end-tidal carbon dioxide levels in the analysis of the images, the quantification and removal of image intensity variations correlated to breathing and end-tidal carbon dioxide changes could be performed. The technique generally accepted for this analysis, however, uses respiration signals averaged over a 3 second period. Because normal respiratory rate is approximately one breath every 3 to 5 seconds, it was hypothesized that performing the correction using the average breathing data set would miss much of the actual respiration induced variation in each image. Therefore, a new technique for removing signal that covaries with the actual breathing values present during the collection of each image was introduced. (Abstract shortened by UMI.)

Family nurture intervention (FNI): methods and treatment protocol of a randomized controlled trial in the NICU.

PubMed

Welch, Martha G; Hofer, Myron A; Brunelli, Susan A; Stark, Raymond I; Andrews, Howard F; Austin, Judy; Myers, Michael M

2012-02-07

The stress that results from preterm birth, requisite acute care and prolonged physical separation in the Neonatal Intensive Care Unit (NICU) can have adverse physiological/psychological effects on both the infant and the mother. In particular, the experience compromises the establishment and maintenance of optimal mother-infant relationship, the subsequent development of the infant, and the mother's emotional well-being. These findings highlight the importance of investigating early interventions that are designed to overcome or reduce the effects of these environmental insults and challenges. This study is a randomized controlled trial (RCT) with blinded assessment comparing Standard Care (SC) with a novel Family Nurture Intervention (FNI). FNI targets preterm infants born 26-34 weeks postmenstrual age (PMA) and their mothers in the NICU. The intervention incorporates elements of mother-infant interventions with known efficacy and organizes them under a new theoretical context referred to collectively as calming activities. This intervention is facilitated by specially trained Nurture Specialists in three ways: 1) In the isolette through calming interactions between mother and infant via odor exchange, firm sustained touch and vocal soothing, and eye contact; 2) Outside the isolette during holding and feeding via the Calming Cycle; and 3) through family sessions designed to engage help and support the mother. In concert with infant neurobehavioral and physiological assessments from birth through 24 months corrected age (CA), maternal assessments are made using standard tools including anxiety, depression, attachment, support systems, temperament as well as physiological stress parameters. Quality of mother-infant interaction is also assessed. Our projected enrolment is 260 families (130 per group). The FNI is designed to increase biologically important activities and behaviors that enhance maternally-mediated sensory experiences of preterm infants, as well as infant-mediated sensory experiences of the mother. Consequently, we are enlarging the testing of preterm infant neurodevelopment beyond that of previous research to include outcomes related to mother-infant interactions and mother-infant co-regulation. Our primary objective is to determine whether repeated engagement of the mother and her infant in the intervention's calming activities will improve the infant's developmental trajectory with respect to multiple outcomes. Our secondary objective is to assess the effectiveness of FNI in the physiological and psychological co-regulation of the mother and infant. We include aspects of neurodevelopment that have not been comprehensively measured in previous NICU interventions. ClinicalTrials.gov: NCT01439269.

Family nurture intervention (FNI): methods and treatment protocol of a randomized controlled trial in the NICU

PubMed Central

2012-01-01

Background The stress that results from preterm birth, requisite acute care and prolonged physical separation in the Neonatal Intensive Care Unit (NICU) can have adverse physiological/psychological effects on both the infant and the mother. In particular, the experience compromises the establishment and maintenance of optimal mother-infant relationship, the subsequent development of the infant, and the mother's emotional well-being. These findings highlight the importance of investigating early interventions that are designed to overcome or reduce the effects of these environmental insults and challenges. Methods This study is a randomized controlled trial (RCT) with blinded assessment comparing Standard Care (SC) with a novel Family Nurture Intervention (FNI). FNI targets preterm infants born 26-34 weeks postmenstrual age (PMA) and their mothers in the NICU. The intervention incorporates elements of mother-infant interventions with known efficacy and organizes them under a new theoretical context referred to collectively as calming activities. This intervention is facilitated by specially trained Nurture Specialists in three ways: 1) In the isolette through calming interactions between mother and infant via odor exchange, firm sustained touch and vocal soothing, and eye contact; 2) Outside the isolette during holding and feeding via the Calming Cycle; and 3) through family sessions designed to engage help and support the mother. In concert with infant neurobehavioral and physiological assessments from birth through 24 months corrected age (CA), maternal assessments are made using standard tools including anxiety, depression, attachment, support systems, temperament as well as physiological stress parameters. Quality of mother-infant interaction is also assessed. Our projected enrolment is 260 families (130 per group). Discussion The FNI is designed to increase biologically important activities and behaviors that enhance maternally-mediated sensory experiences of preterm infants, as well as infant-mediated sensory experiences of the mother. Consequently, we are enlarging the testing of preterm infant neurodevelopment beyond that of previous research to include outcomes related to mother-infant interactions and mother-infant co-regulation. Our primary objective is to determine whether repeated engagement of the mother and her infant in the intervention's calming activities will improve the infant's developmental trajectory with respect to multiple outcomes. Our secondary objective is to assess the effectiveness of FNI in the physiological and psychological co-regulation of the mother and infant. We include aspects of neurodevelopment that have not been comprehensively measured in previous NICU interventions. Trial Registration ClinicalTrials.gov: NCT01439269 PMID:22314029

Medicinal cannabis: rational guidelines for dosing.

PubMed

Carter, Gregory T; Weydt, Patrick; Kyashna-Tocha, Muraco; Abrams, Donald I

2004-05-01

The medicinal value of cannabis (marijuana) is well documented in the medical literature. Cannabinoids, the active ingredients in cannabis, have many distinct pharmacological properties. These include analgesic, anti-emetic, anti-oxidative, neuroprotective and anti-inflammatory activity, as well as modulation of glial cells and tumor growth regulation. Concurrent with all these advances in the understanding of the physiological and pharmacological mechanisms of cannabis, there is a strong need for developing rational guidelines for dosing. This paper will review the known chemistry and pharmacology of cannabis and, on that basis, discuss rational guidelines for dosing.

[Methuosis: a novel type of cell death].

PubMed

Cai, Hongbing; Liu, Jinkun; Fan, Qin; Li, Xin

2013-12-01

Cell death is a major physiological or pathological phenomenon in life activities. The classic forms of cell death include apoptosis, necrosis, and autophagy. Recently, a novel type of cell death has been observed and termed as methuosis, in which excessive stimuli can induce cytoplasmic uptake and accumulation of small bubbles that gradually merge into giant vacuoles, eventually leading to decreased cellular metabolic activity, cell membrane rupture and cell death. In this article, we describe the nomenclature, morphological characteristics and underlying mechanisms of methuosis, compare methuosis with autophagy, oncosis and paraptosis, and review the related researches.

Actions of Steroids: New Neurotransmitters

PubMed Central

Cornil, Charlotte A.; Mittelman-Smith, Melinda A.; Rainville, Jennifer R.; Remage-Healey, Luke; Sinchak, Kevin; Micevych, Paul E.

2016-01-01

Over the past two decades, the classical understanding of steroid action has been updated to include rapid, membrane-initiated, neurotransmitter-like functions. While steroids were known to function on very short time spans to induce physiological and behavioral changes, the mechanisms by which these changes occur are now becoming more clear. In avian systems, rapid estradiol effects can be mediated via local alterations in aromatase activity, which precisely regulates the temporal and spatial availability of estrogens. Acute regulation of brain-derived estrogens has been shown to rapidly affect sensorimotor function and sexual motivation in birds. In rodents, estrogens and progesterone are critical for reproduction, including preovulatory events and female sexual receptivity. Membrane progesterone receptor as well as classical progesterone receptor trafficked to the membrane mediate reproductive-related hypothalamic physiology, via second messenger systems with dopamine-induced cell signals. In addition to these relatively rapid actions, estrogen membrane-initiated signaling elicits changes in morphology. In the arcuate nucleus of the hypothalamus, these changes are needed for lordosis behavior. Recent evidence also demonstrates that membrane glucocorticoid receptor is present in numerous cell types and species, including mammals. Further, membrane glucocorticoid receptor influences glucocorticoid receptor translocation to the nucleus effecting transcriptional activity. The studies presented here underscore the evidence that steroids behave like neurotransmitters to regulate CNS functions. In the future, we hope to fully characterize steroid receptor-specific functions in the brain. PMID:27911748

Intervention to lower anxiety of 18F-FDG PET/CT patients by use of audiovisual imagery during the uptake phase before imaging.

PubMed

Vogel, Wouter V; Valdés Olmos, Renato A; Tijs, Tim J W; Gillies, Murray F; van Elswijk, Gijs; Vogt, Juergen

2012-06-01

Many patients referred for PET suffer from anxiety, possibly affecting the workflow and patient experience. In addition, patient anxiety may affect image quality through uptake of (18)F-FDG in muscles or brown adipose tissue (BAT).This study investigated the effects of a nonpharmacologic intervention-the use of audiovisual imagery in the PET uptake room-on patient anxiety and false-positive uptake of (18)F-FDG (in muscles and BAT). A 2-stage study was conducted on 101 patients. The cohort undergoing the intervention included 51 patients. The first stage (n = 35) included physiologic measurements (cardiovascular activity, muscular activity, skin conductance, and cortisol), a state anxiety questionnaire, and visual evaluation of (18)F-FDG uptake in muscles and BAT; the second stage (n = 66) included only the state anxiety questionnaire and the (18)F-FDG uptake evaluation. Throughout the stay in the uptake room, a significant decrease in overall anxiety was found, together with several other significant changes in patient physiology. In the cohort with audiovisual intervention, however, the decrease in patient anxiety was significantly larger. The cohort with intervention also showed significantly lower (18)F-FDG uptake in BAT but not in muscles. The investigated audiovisual intervention helps to lower patient anxiety in the PET uptake room and can lower false-positive (18)F-FDG uptake in BAT.

Compulsory winding in the opposite direction of climbing plants promotes yield.

PubMed

Kodama, Yoshiaki; Tezuka, Takafumi

2004-04-01

The stem of kidney bean plant (Phaseolus vulgaris L., cv. Kentucky 101), a typical dextrorse climbing plant, was subjected to compulsorily sinistrorse-winding. The compulsory sinistrorse-winding induced changes in physiological activities. The number of pods with immature seeds (used as vegetable) was doubled and the fresh weight of the pods also significantly increased by sinistrorse-winding. Compulsory sinistrorse-winding increased chlorophyll content, photosynthetic rate, respiration, nodule formation, N(2)-fixation, glutamine synthetase [L-glutamate: ammonia ligase (ADP-forming); E.C. 6.3.1.2] activity and protein content. Thus, it seems to affect the basic physiological processes that promote physiological activities though the action mechanism is unknown.

Overview Of Impedance Sensors

NASA Astrophysics Data System (ADS)

Abele, John E.

1989-08-01

Electrical impedance has been one of the many "tools of great promise" that physicians have employed in their quest to measure and/or monitor body function or physiologic events. So far, the expectations for its success have always exceeded its performance. In simplistic terms, physiologic impedance is a measure of the resistance in the volume between electrodes which changes as a function of changes in that volume, the relative impedance of that volume, or a combination of these two. The history and principles of electrical impedance are very nicely reviewed by Geddes and Baker in their textbook "Principles of Applied Biomedical Instrumentation". It is humbling, however, to note that Cremer recorded variations in electrical impedance in frog hearts as early as 1907. The list of potential applications includes the measurement of thyroid function, estrogen activity, galvanic skin reflex, respiration, blood flow by conductivity dilution, nervous activity and eye movement. Commercial devices employing impedance have been and are being used to measure respiration (pneumographs and apneamonitors), pulse volume (impedance phlebographs) and even noninvasive cardiac output.

Dual personality of Mad1: regulation of nuclear import by a spindle assembly checkpoint protein.

PubMed

Cairo, Lucas V; Ptak, Christopher; Wozniak, Richard W

2013-01-01

Nuclear transport is a dynamic process that can be modulated in response to changes in cellular physiology. We recently reported that the transport activity of yeast nuclear pore complexes (NPCs) is altered in response to kinetochore-microtubule (KT-MT) interaction defects. Specifically, KT detachment from MTs activates a signaling pathway that prevents the nuclear import of cargos by the nuclear transport factor Kap121p. This loss of Kap121p-mediated import is thought to influence the nuclear environment, including the phosphorylation state of nuclear proteins. A key regulator of this process is the spindle assembly checkpoint protein Mad1p. In response to unattached KTs, Mad1p dynamically cycles between NPCs and KTs. This cycling appears to induce NPC molecular rearrangements that prevent the nuclear import of Kap121p-cargo complexes. Here, we discuss the underlying mechanisms and the physiological relevance of Mad1p cycling and the inhibition of Kap121p-mediated nuclear import, focusing on outstanding questions within the pathway.

Muscles provide protection during microbial infection by activating innate immune response pathways in Drosophila and zebrafish.

PubMed

Chatterjee, Arunita; Roy, Debasish; Patnaik, Esha; Nongthomba, Upendra

2016-06-01

Muscle contraction brings about movement and locomotion in animals. However, muscles have also been implicated in several atypical physiological processes including immune response. The role of muscles in immunity and the mechanism involved has not yet been deciphered. In this paper, using Drosophila indirect flight muscles (IFMs) as a model, we show that muscles are immune-responsive tissues. Flies with defective IFMs are incapable of mounting a potent humoral immune response. Upon immune challenge, the IFMs produce anti-microbial peptides (AMPs) through the activation of canonical signaling pathways, and these IFM-synthesized AMPs are essential for survival upon infection. The trunk muscles of zebrafish, a vertebrate model system, also possess the capacity to mount an immune response against bacterial infections, thus establishing that immune responsiveness of muscles is evolutionarily conserved. Our results suggest that physiologically fit muscles might boost the innate immune response of an individual. © 2016. Published by The Company of Biologists Ltd.

Changes in energy metabolism accompanying pitting in blueberries stored at low temperature.

PubMed

Zhou, Qian; Zhang, Chunlei; Cheng, Shunchang; Wei, Baodong; Liu, Xiuying; Ji, Shujuan

2014-12-01

Low-temperature storage and transport of blueberries is widely practiced in commercial blueberry production. In this research, the storage life of blueberries was extended at low temperature, but fruit stored for 30 d at 0°C pitted after 2d at room-temperature. Fruit cellular structure and physiological parameters accompanying pitting in blueberries were changed. The objective of this research was to characterise properties of energy metabolism accompanying pitting in blueberries during storage, including adenosine phosphates and mitochondrial enzymes involved in stress responses. Physiological and metabolic disorders, changes in cell ultrastructure, energy content and ATPase enzyme activity were observed in pitting blueberries. Energy shortages and increased activity of phenylalanine ammonia lyase (PAL) and lipoxygenase (LOX) were observed in fruit kept at shelf life. The results suggested that sufficient available energy status and a stable enzymatic system in blueberries collectively contribute to improve chilling tolerance, thereby alleviating pitting and maintaining quality of blueberry fruit in long-term cold storage. Copyright © 2014 Elsevier Ltd. All rights reserved.

The checkered puffer (Spheroides testudineus) and its helminths as bioindicators of chemical pollution in Yucatan coastal lagoons.

PubMed

Pech, Daniel; Vidal-Martínez, Víctor M; Aguirre-Macedo, M Leopoldina; Gold-Bouchot, Gerardo; Herrera-Silveira, Jorge; Zapata-Pérez, Omar; Marcogliese, David J

2009-03-15

The suitability of using helminth communities as bioindicators of environmental quality of the Yucatan coastal lagoons status was tested on the checkered puffer (Spheroides testudineus) in four coastal lagoons along the Yucatan coast. The concentration of chemical pollutants in sediments, water quality parameters, helminth infracommunity characteristics, as well as fish physiological biomarkers, including EROD (7-ethoxyresorufin-O-deethylase) and catalase activities, were measured. Results from sediment analyses demonstrated the presence of hydrocarbons, organochlorine pesticides and polychlorinated biphenyls at varying concentrations, some of which exceeded the Probability Effect Level (PEL). Significant negative associations among organochlorine pesticides, infracommunity characteristics and fish physiological responses were observed in most of the lagoons. Results suggest that EROD activity and parasite infracommunity characteristics could be useful tools to evaluate the effects of chemical pollutants on the fish host and in the environment. Importantly, certain parasites appear to influence biomarker measurements, indicating that parasites should be considered in ecotoxicological studies.

Physical culture as the basis of students' healthy lifestyle.

PubMed

Kharissova, N; Kharissova, L; Smirnov, I; Kosibaeva, A; Mindubaeva, F

2015-04-01

The present study aimed at investigation of the relationship between physiological features of cardiorespiratory system of a group of athletes with individually-typological charac-teristics of the organism (age, type of constitution, sports experience, the degree of adaptation) to physical activities on the basis of a comprehensive study of the cardiorespiratory system. The study was conducted on 450 students from 18 to 24 years of age from Kazakhstan, Russia, India, and Pakistan to evaluate the influence of physical culture and sports on the formation of a healthy lifestyle of young people in higher education institutions. The students were divided into groups - the first group - student 18-20 years of age; the second group - students 21-24 years of age; the control group included students of the same age not actively involved in sports (2 lessons of physical training per week). The relationship between physiological features of cardiorespiratory system of athletes and individually-typological characteristics of the organism (age, type of constitution, sports experience, the degree of adaptation) was determined.

Physiology of Plants, Science (Experimental): 5315.41.

ERIC Educational Resources Information Center

Gunn, William C.

This unit of instruction deals with the physiological activities of plants. Attention is focused on the principles which underlie the activities of the typical green land plant. Emphasis is placed on biological processes such as photosynthesis, water transport, light responses, mineral nutrition, reproduction, and growth. The prerequisite for…

Channel function reconstitution and re-animation: a single-channel strategy in the postcrystal age.

PubMed

Oiki, Shigetoshi

2015-06-15

The most essential properties of ion channels for their physiologically relevant functions are ion-selective permeation and gating. Among the channel species, the potassium channel is primordial and the most ubiquitous in the biological world, and knowledge of this channel underlies the understanding of features of other ion channels. The strategy applied to studying channels changed dramatically after the crystal structure of the potassium channel was resolved. Given the abundant structural information available, we exploited the bacterial KcsA potassium channel as a simple model channel. In the postcrystal age, there are two effective frameworks with which to decipher the functional codes present in the channel structure, namely reconstitution and re-animation. Complex channel proteins are decomposed into essential functional components, and well-examined parts are rebuilt for integrating channel function in the membrane (reconstitution). Permeation and gating are dynamic operations, and one imagines the active channel by breathing life into the 'frozen' crystal (re-animation). Capturing the motion of channels at the single-molecule level is necessary to characterize the behaviour of functioning channels. Advanced techniques, including diffracted X-ray tracking, lipid bilayer methods and high-speed atomic force microscopy, have been used. Here, I present dynamic pictures of the KcsA potassium channel from the submolecular conformational changes to the supramolecular collective behaviour of channels in the membrane. These results form an integrated picture of the active channel and offer insights into the processes underlying the physiological function of the channel in the cell membrane. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

Effect of health-related stereotypes on physiological responses of hypertensive middle-aged and older men.

PubMed

Auman, Corinne; Bosworth, Hayden B; Hess, Thomas M

2005-01-01

This study examined the influence of health stereotypes on stress response among middle-aged and older men. It was hypothesized that anxiety and cardiovascular reactivity would increase when health stereotypes were activated among veterans seeking care in an outpatient setting. Among a sample of 122 veteran patients with hypertension, the level of stereotype activation varied by means of reference to either their health status (health stereotypes) or, conversely, some personally valued leisure activities (no stereotype activation). Predicted stereotype-related increases in anxiety, galvanized skin conductance, and blood pressure were evident. Potential explanations for these results are explored, including those relating to the negative health stereotypes associated with being a patient.

Physiological responses to simulated firefighter exercise protocols in varying environments.

PubMed

Horn, Gavin P; Kesler, Richard M; Motl, Robert W; Hsiao-Wecksler, Elizabeth T; Klaren, Rachel E; Ensari, Ipek; Petrucci, Matthew N; Fernhall, Bo; Rosengren, Karl S

2015-01-01

For decades, research to quantify the effects of firefighting activities and personal protective equipment on physiology and biomechanics has been conducted in a variety of testing environments. It is unknown if these different environments provide similar information and comparable responses. A novel Firefighting Activities Station, which simulates four common fireground tasks, is presented for use with an environmental chamber in a controlled laboratory setting. Nineteen firefighters completed three different exercise protocols following common research practices. Simulated firefighting activities conducted in an environmental chamber or live-fire structures elicited similar physiological responses (max heart rate: 190.1 vs 188.0 bpm, core temperature response: 0.047°C/min vs 0.043°C/min) and accelerometry counts. However, the response to a treadmill protocol commonly used in laboratory settings resulted in significantly lower heart rate (178.4 vs 188.0 bpm), core temperature response (0.037°C/min vs 0.043°C/min) and physical activity counts compared with firefighting activities in the burn building. Practitioner Summary: We introduce a new approach for simulating realistic firefighting activities in a controlled laboratory environment for ergonomics assessment of fire service equipment and personnel. Physiological responses to this proposed protocol more closely replicate those from live-fire activities than a traditional treadmill protocol and are simple to replicate and standardise.

Physiology Applied to Everyday: The Practice of Professional Contextualization of Physiology Concepts as a Way of Facilitating Learning

ERIC Educational Resources Information Center

Borges, Sidnei; Mello-Carpes, Pâmela Billig

2014-01-01

The teaching of Physiology is indispensable in many biological and health disciplines. Physiology is one of the major components of the curriculum in a number of life science courses, including the study of life, cells, tissues, and organisms as well as their functions. A bigger challenge for physiology teachers is to make physiological concepts…

Aversive emotional interference impacts behavior and prefronto-striatal activity during increasing attentional control.

PubMed

Papazacharias, Apostolos; Taurisano, Paolo; Fazio, Leonardo; Gelao, Barbara; Di Giorgio, Annabella; Lo Bianco, Luciana; Quarto, Tiziana; Mancini, Marina; Porcelli, Annamaria; Romano, Raffaella; Caforio, Grazia; Todarello, Orlando; Popolizio, Teresa; Blasi, Giuseppe; Bertolino, Alessandro

2015-01-01

Earlier studies have demonstrated that emotional stimulation modulates attentional processing during goal-directed behavior and related activity of a brain network including the inferior frontal gyrus (IFG) and the caudate nucleus. However, it is not clear how emotional interference modulates behavior and brain physiology during variation in attentional control, a relevant question for everyday life situations in which both emotional stimuli and cognitive load vary. The aim of this study was to investigate the impact of negative emotions on behavior and activity in IFG and caudate nucleus during increasing levels of attentional control. Twenty two healthy subjects underwent event-related functional magnetic resonance imaging while performing a task in which neutral or fearful facial expressions were displayed before stimuli eliciting increasing levels of attentional control processing. Results indicated slower reaction time (RT) and greater right IFG activity when fearful compared with neutral facial expressions preceded the low level of attentional control. On the other hand, fearful facial expressions preceding the intermediate level of attentional control elicited faster behavioral responses and greater activity in the right and left sides of the caudate. Finally, correlation analysis indicated a relationship between behavioral correlates of attentional control after emotional interference and right IFG activity. All together, these results suggest that the impact of negative emotions on attentional processing is differentially elicited at the behavioral and physiological levels as a function of cognitive load.

Aversive emotional interference impacts behavior and prefronto-striatal activity during increasing attentional control

PubMed Central

Papazacharias, Apostolos; Taurisano, Paolo; Fazio, Leonardo; Gelao, Barbara; Di Giorgio, Annabella; Lo Bianco, Luciana; Quarto, Tiziana; Mancini, Marina; Porcelli, Annamaria; Romano, Raffaella; Caforio, Grazia; Todarello, Orlando; Popolizio, Teresa; Blasi, Giuseppe; Bertolino, Alessandro

2015-01-01

Earlier studies have demonstrated that emotional stimulation modulates attentional processing during goal-directed behavior and related activity of a brain network including the inferior frontal gyrus (IFG) and the caudate nucleus. However, it is not clear how emotional interference modulates behavior and brain physiology during variation in attentional control, a relevant question for everyday life situations in which both emotional stimuli and cognitive load vary. The aim of this study was to investigate the impact of negative emotions on behavior and activity in IFG and caudate nucleus during increasing levels of attentional control. Twenty two healthy subjects underwent event-related functional magnetic resonance imaging while performing a task in which neutral or fearful facial expressions were displayed before stimuli eliciting increasing levels of attentional control processing. Results indicated slower reaction time (RT) and greater right IFG activity when fearful compared with neutral facial expressions preceded the low level of attentional control. On the other hand, fearful facial expressions preceding the intermediate level of attentional control elicited faster behavioral responses and greater activity in the right and left sides of the caudate. Finally, correlation analysis indicated a relationship between behavioral correlates of attentional control after emotional interference and right IFG activity. All together, these results suggest that the impact of negative emotions on attentional processing is differentially elicited at the behavioral and physiological levels as a function of cognitive load. PMID:25954172

Activation of CAR and PXR by Dietary, Environmental and Occupational Chemicals Alters Drug Metabolism, Intermediary Metabolism, and Cell Proliferation

PubMed Central

Hernandez, J.P.; Mota, L.C.; Baldwin, W.S.

2010-01-01

The constitutive androstane receptor (CAR) and the pregnane × receptor (PXR) are activated by a variety of endogenous and exogenous ligands, such as steroid hormones, bile acids, pharmaceuticals, and environmental, dietary, and occupational chemicals. In turn, they induce phase I–III detoxification enzymes and transporters that help eliminate these chemicals. Because many of the chemicals that activate CAR and PXR are environmentally-relevant (dietary and anthropogenic), studies need to address whether these chemicals or mixtures of these chemicals may increase the susceptibility to adverse drug interactions. In addition, CAR and PXR are involved in hepatic proliferation, intermediary metabolism, and protection from cholestasis. Therefore, activation of CAR and PXR may have a wide variety of implications for personalized medicine through physiological effects on metabolism and cell proliferation; some beneficial and others adverse. Identifying the chemicals that activate these promiscuous nuclear receptors and understanding how these chemicals may act in concert will help us predict adverse drug reactions (ADRs), predict cholestasis and steatosis, and regulate intermediary metabolism. This review summarizes the available data on CAR and PXR, including the environmental chemicals that activate these receptors, the genes they control, and the physiological processes that are perturbed or depend on CAR and PXR action. This knowledge contributes to a foundation that will be necessary to discern interindividual differences in the downstream biological pathways regulated by these key nuclear receptors. PMID:20871735

Fundamental Activity Constraints Lead to Specific Interpretations of the Connectome.

PubMed

Schuecker, Jannis; Schmidt, Maximilian; van Albada, Sacha J; Diesmann, Markus; Helias, Moritz

2017-02-01

The continuous integration of experimental data into coherent models of the brain is an increasing challenge of modern neuroscience. Such models provide a bridge between structure and activity, and identify the mechanisms giving rise to experimental observations. Nevertheless, structurally realistic network models of spiking neurons are necessarily underconstrained even if experimental data on brain connectivity are incorporated to the best of our knowledge. Guided by physiological observations, any model must therefore explore the parameter ranges within the uncertainty of the data. Based on simulation results alone, however, the mechanisms underlying stable and physiologically realistic activity often remain obscure. We here employ a mean-field reduction of the dynamics, which allows us to include activity constraints into the process of model construction. We shape the phase space of a multi-scale network model of the vision-related areas of macaque cortex by systematically refining its connectivity. Fundamental constraints on the activity, i.e., prohibiting quiescence and requiring global stability, prove sufficient to obtain realistic layer- and area-specific activity. Only small adaptations of the structure are required, showing that the network operates close to an instability. The procedure identifies components of the network critical to its collective dynamics and creates hypotheses for structural data and future experiments. The method can be applied to networks involving any neuron model with a known gain function.

Differences in autonomic physiological responses between good and poor inductive reasoners.

PubMed

Melis, C; van Boxtel, A

2001-11-01

We investigated individual- and task-related differences in autonomic physiological responses induced by time limited figural and verbal inductive reasoning tasks. In a group of 52 participants, the percentage of correctly responded task items was evaluated together with nine different autonomic physiological response measures and respiration rate (RR). Weighted multidimensional scaling analyses of the physiological responses revealed three underlying dimensions, primarily characterized by RR, parasympathetic, and sympathetic activity. RR and sympathetic activity appeared to be relatively more important response dimensions for poor reasoners, whereas parasympathetic responsivity was relatively more important for good reasoners. These results suggest that poor reasoners showed higher levels of cognitive processing intensity than good reasoners. Furthermore, for the good reasoners, the dimension of sympathetic activity was relatively more important during the figural than during the verbal reasoning task, which was explained in terms of hemispheric lateralization in autonomic function.

Observing and understanding arterial and venous circulation differences in a physiology laboratory activity.

PubMed

Altermann, Caroline; Gonçalves, Rithiele; Lara, Marcus Vinícius S; Neves, Ben-Hur S; Mello-Carpes, Pâmela B

2015-12-01

The purpose of the present article is to describe three simple practical experiments that aim to observe and discuss the anatomic and physiological functions and differences between arteries and veins as well as the alterations observed in skin blood flow in different situations. For this activity, students were divided in small groups. In each group, a volunteer is recruited for each experiment. The experiments only require a sphygmomanometer, rubber bands, and a clock and allow students to develop a hypothesis to explain the different responses to the interruption of arterial and venous blood flow. At the end, students prepare a short report, and the results are discussed. This activity allows students to perceive the presence of physiology in their daily lives and helps them to understand the concepts related to the cardiovascular system and hemodynamics. Copyright © 2015 The American Physiological Society.

Effects of gender and game type on autonomic nervous system physiological parameters in long-hour online game players.

PubMed

Lin, Tung-Cheng

2013-11-01

Online game playing may induce physiological effects. However, the physical mechanisms that cause these effects remain unclear. The purpose of this study was to examine the physiological effects of long-hour online gaming from an autonomic nervous system (ANS) perspective. Heart rate variability (HRV), a valid and noninvasive electrocardiographic method widely used to investigate ANS balance, was used to measure physiological effect parameters. This study used a five-time, repeated measures, mixed factorial design. Results found that playing violent games causes significantly higher sympathetic activity and diastolic blood pressure than playing nonviolent games. Long-hour online game playing resulted in the gradual dominance of the parasympathetic nervous system due to physical exhaustion. Gaming workload was found to modulate the gender effects, with males registering significantly higher sympathetic activity and females significantly higher parasympathetic activity in the higher gaming workload group.

Movement, migration, and smolting of Atlantic salmon (Salmo salar)

USGS Publications Warehouse

McCormick, S.D.; Hansen, Lonnie P.; Quinn, T.P.; Saunders, R.L.

1998-01-01

A variety of movements characterize the behavioral plasticity of Atlantic salmon (Salmo salar) in fresh water, including movements of fry from redds, establishment of feeding territories, spawning movements of sexually mature male parr, movement to and from winter habitat, and smolt migration in spring. Smolting is an adaptive specialization for downstream migration, seawater entry, and marine residence. While still in fresh water, smolts become silvery and streamlined, lose their positive rheotaxis and territoriality, and begin schooling. Physiological changes include increased salinity tolerance, olfactory sensitivity, metabolic rate, scope for growth, and altered hemoglobin and visual pigments. Through their impact on the neuroendocrine system, photoperiod and temperature regulate physiological changes, whereas temperature and water flow may initiate migration. Smolt survival is affected by a limited period of readiness (a physiological 'smolt window') and the timing of seawater entry with environmental conditions such as temperature, food, and predators (an ecological 'smolt window'). Smolt development is adversely affected by acidity, pollutants, and improper rearing conditions, and is often more sensitive than other life stages. Unfortunately, the migration corridor of smolts (mainstems of rivers and estuaries) are the most heavily impacted by pollution, dams, and other anthropogenic activities that may be directly lethal or increase mortality by delaying or inhibiting smolt migration.

Psycho-Physiological Contributions of Physical Activity and Sports for Girls.

ERIC Educational Resources Information Center

Bunker, Linda K

1998-01-01

Sport and physical activity contribute to the physical movement capabilities of girls, the health status of their bodies, the values and ethical behaviors they develop, and their personal development of a unique identity. This paper offers an overview of contributions and potential challenges related to physiological dimensions and psychosocial…

Important Physiological Parameters and Physical Activity Data for Evaluating Exposure Modeling Performance: a Synthesis

EPA Science Inventory

The purpose of this report is to develop a database of physiological parameters needed for understanding and evaluating performance of the APEX and SHEDS exposure/intake dose rate model used by the Environmental Protection Agency (EPA) as part of its regulatory activities. The A...

Electrodermal Recording and fMRI to Inform Sensorimotor Recovery in Stroke Patients

PubMed Central

MacIntosh, Bradley J.; McIlroy, William E.; Mraz, Richard; Staines, W. Richard; Black, Sandra E.; Graham, Simon J.

2016-01-01

Background Functional magnetic resonance imaging (fMRI) appears to be useful for investigating motor recovery after stroke. Some of the potential confounders of brain activation studies, however, could be mitigated through complementary physiological monitoring. Objective To investigate a sensorimotor fMRI battery that included simultaneous measurement of electrodermal activity in subjects with hemiparetic stroke to provide a measure related to the sense of effort during motor performance. Methods Bilateral hand and ankle tasks were performed by 6 patients with stroke (2 subacute, 4 chronic) during imaging with blood oxygen level-dependent (BOLD) fMRI using an event-related design. BOLD percent changes, peak activation, and laterality index values were calculated in the sensorimotor cortex. Electrodermal recordings were made concurrently and used as a regressor. Results Sensorimotor BOLD time series and percent change values provided evidence of an intact motor network in each of these well-recovered patients. During tasks involving the hemiparetic limb, electrodermal activity changes were variable in amplitude, and electrodermal activity time-series data showed significant correlations with fMRI in 3 of 6 patients. No such correlations were observed for control tasks involving the unaffected lower limb. Conclusions Electrodermal activity activation maps implicated the contralesional over the ipsilesional hemisphere, supporting the notion that stroke patients may require higher order motor processing to perform simple tasks. Electrodermal activity recordings may be useful as a physiological marker of differences in effort required during movements of a subject’s hemiparetic compared with the unaffected limb during fMRI studies. PMID:18784267

Autonomic physiological data associated with simulator discomfort

NASA Technical Reports Server (NTRS)

Miller, James C.; Sharkey, Thomas J.; Graham, Glenna A.; Mccauley, Michael E.

1993-01-01

The development of a physiological monitoring capability for the Army's advanced helicopter simulator facility is reported. Additionally, preliminary physiological data is presented. Our objective was to demonstrate the sensitivity of physiological measures in this simulator to self-reported simulator sickness. The data suggested that heart period, hypergastria, and skin conductance level were more sensitive to simulator sickness than were vagal tone and normal electrogastric activity.

Co-Adaptive Aiding and Automation Enhance Operator Performance

DTIC Science & Technology

2013-03-01

activation system. There is a close relation between physiologically activated adaptive aiding and brain- computer interfaces ( BCI ). BCI here refers...classification of EEG signals (Farwell & Donchin, 1988). Physiologically activated adaptive aiding is, in a sense, a special case of BCI wherein the...as passive BCI , e.g. Zander, Kothe, Jatzev, & 3 Distribution A: Approved for public release; distribution unlimited. 88 ABW Cleared 05/13/2013

Protein tyrosine kinase regulation by ubiquitination: Critical roles of Cbl-family ubiquitin ligases

PubMed Central

Mohapatra, Bhopal; Ahmad, Gulzar; Nadeau, Scott; Zutshi, Neha; An, Wei; Scheffe, Sarah; Dong, Lin; Feng, Dan; Goetz, Benjamin; Arya, Priyanka; Bailey, Tameka A.; Palermo, Nicholas; Borgstahl, Gloria E.O.; Natarajan, Amarnath; Raja, Srikumar M.; Naramura, Mayumi; Band, Vimla; Band, Hamid

2012-01-01

Protein tyrosine kinases (PTKs) coordinate a broad spectrum of cellular responses to extracellular stimuli and cell–cell interactions during development, tissue homeostasis, and responses to environmental challenges. Thus, an understanding of the regulatory mechanisms that ensure physiological PTK function and potential aberrations of these regulatory processes during diseases such as cancer are of broad interest in biology and medicine. Aside from the expected role of phospho-tyrosine phosphatases, recent studies have revealed a critical role of covalent modification of activated PTKs with ubiquitin as a critical mechanism of their negative regulation. Members of the Cbl protein family (Cbl, Cbl-b and Cbl-c in mammals) have emerged as dominant “activated PTK-selective” ubiquitin ligases. Structural, biochemical and cell biological studies have established that Cbl protein-dependent ubiquitination targets activated PTKs for degradation either by facilitating their endocytic sorting into lysosomes or by promoting their proteasomal degradation. This mechanism also targets PTK signaling intermediates that become associated with Cbl proteins in a PTK activation-dependent manner. Cellular and animal studies have established that the relatively broadly expressed mammalian Cbl family members Cbl and Cbl-b play key physiological roles, including their critical functions to prevent the transition of normal immune responses into autoimmune disease and as tumor suppressors; the latter function has received validation from human studies linking mutations in Cbl to human leukemia. These newer insights together with embryonic lethality seen in mice with a combined deletion of Cbl and Cbl-b genes suggest an unappreciated role of the Cbl family proteins, and by implication the ubiquitin-dependent control of activated PTKs, in stem/progenitor cell maintenance. Future studies of existing and emerging animal models and their various cell lineages should help test the broader implications of the evolutionarily-conserved Cbl family protein-mediated, ubiquitin-dependent, negative regulation of activated PTKs in physiology and disease. PMID:23085373