American Psychological Association 1989 Annual Convention on Sustained Operations Research: A Blend of Psychology and Physiology Held in New Orleans, Louisiana on 11-15 August 1989

DTIC Science & Technology

1989-12-27

is important to note also that as interdisciplinary studies have gained in -kj ’- popularity, theories incorporating physical and behavi6ral hypothesis...have gained strength due to approaches which focus multiple measures on single factors. Th( study of military sustained performance/operations...related fields of study . These environmental and interdisciplinary areas of study are typically sleep deprivation, work load, exercise physiology

Warming and Elevated CO2 Interact to Drive Rapid Shifts in Marine Community Production.

PubMed

Sorte, Cascade J B; Bracken, Matthew E S

2015-01-01

Predicting the outcome of future climate change requires an understanding of how alterations in multiple environmental factors manifest in natural communities and affect ecosystem functioning. We conducted an in situ, fully factorial field manipulation of CO2 and temperature on a rocky shoreline in southeastern Alaska, USA. Warming strongly impacted functioning of tide pool systems within one month, with the rate of net community production (NCP) more than doubling in warmed pools under ambient CO2 levels relative to initial NCP values. However, in pools with added CO2, NCP was unaffected by warming. Productivity responses paralleled changes in the carbon-to-nitrogen ratio of a red alga, the most abundant primary producer species in the system, highlighting the direct link between physiology and ecosystem functioning. These observed changes in algal physiology and community productivity in response to our manipulations indicate the potential for natural systems to shift rapidly in response to changing climatic conditions and for multiple environmental factors to act antagonistically.

Warming and Elevated CO2 Interact to Drive Rapid Shifts in Marine Community Production

PubMed Central

Sorte, Cascade J. B.; Bracken, Matthew E. S.

2015-01-01

Predicting the outcome of future climate change requires an understanding of how alterations in multiple environmental factors manifest in natural communities and affect ecosystem functioning. We conducted an in situ, fully factorial field manipulation of CO2 and temperature on a rocky shoreline in southeastern Alaska, USA. Warming strongly impacted functioning of tide pool systems within one month, with the rate of net community production (NCP) more than doubling in warmed pools under ambient CO2 levels relative to initial NCP values. However, in pools with added CO2, NCP was unaffected by warming. Productivity responses paralleled changes in the carbon-to-nitrogen ratio of a red alga, the most abundant primary producer species in the system, highlighting the direct link between physiology and ecosystem functioning. These observed changes in algal physiology and community productivity in response to our manipulations indicate the potential for natural systems to shift rapidly in response to changing climatic conditions and for multiple environmental factors to act antagonistically. PMID:26714167

A Model Incorporating Some of the Mechanical and Biochemical Factors Underlying Clot Formation and Dissolution in Flowing Blood

DOE PAGES

Anand, M.; Rajagopal, K.; Rajagopal, K. R.

2003-01-01

Multiple interacting mechanisms control the formation and dissolution of clots to maintain blood in a state of delicate balance. In addition to a myriad of biochemical reactions, rheological factors also play a crucial role in modulating the response of blood to external stimuli. To date, a comprehensive model for clot formation and dissolution, that takes into account the biochemical, medical and rheological factors, has not been put into place, the existing models emphasizing either one or the other of the factors. In this paper, after discussing the various biochemical, physiologic and rheological factors at some length, we develop a modelmore » for clot formation and dissolution that incorporates many of the relevant crucial factors that have a bearing on the problem. The model, though just a first step towards understanding a complex phenomenon, goes further than previous models in integrating the biochemical, physiologic and rheological factors that come into play.« less

Response and adaptation of photosynthesis, respiration, and antioxidant systems to elevated CO2 with environmental stress in plants

PubMed Central

Xu, Zhenzhu; Jiang, Yanling; Zhou, Guangsheng

2015-01-01

It is well known that plant photosynthesis and respiration are two fundamental and crucial physiological processes, while the critical role of the antioxidant system in response to abiotic factors is still a focus point for investigating physiological stress. Although one key metabolic process and its response to climatic change have already been reported and reviewed, an integrative review, including several biological processes at multiple scales, has not been well reported. The current review will present a synthesis focusing on the underlying mechanisms in the responses to elevated CO2 at multiple scales, including molecular, cellular, biochemical, physiological, and individual aspects, particularly, for these biological processes under elevated CO2 with other key abiotic stresses, such as heat, drought, and ozone pollution, as well as nitrogen limitation. The present comprehensive review may add timely and substantial information about the topic in recent studies, while it presents what has been well established in previous reviews. First, an outline of the critical biological processes, and an overview of their roles in environmental regulation, is presented. Second, the research advances with regard to the individual subtopics are reviewed, including the response and adaptation of the photosynthetic capacity, respiration, and antioxidant system to CO2 enrichment alone, and its combination with other climatic change factors. Finally, the potential applications for plant responses at various levels to climate change are discussed. The above issue is currently of crucial concern worldwide, and this review may help in a better understanding of how plants deal with elevated CO2 using other mainstream abiotic factors, including molecular, cellular, biochemical, physiological, and whole individual processes, and the better management of the ecological environment, climate change, and sustainable development. PMID:26442017

Panic and phobic anxiety: associations among neuroticism, physiological hyperarousal, anxiety sensitivity, and three phobias.

PubMed

Longley, Susan L; Watson, David; Noyes, Russell; Yoder, Kevin

2006-01-01

A dimensional and psychometrically informed taxonomy of anxiety is emerging, but the specific and nonspecific dimensions of panic and phobic anxiety require greater clarification. In this study, confirmatory factor analyses of data from a sample of 438 college students were used to validate a model of panic and phobic anxiety with six content factors; multiple scales from self-report measures were indicators of each model component. The model included a nonspecific component of (1) neuroticism and two specific components of panic attack, (2) physiological hyperarousal, and (3) anxiety sensitivity. The model also included three phobia components of (4) classically defined agoraphobia, (5) social phobia, and (6) blood-injection phobia. In these data, agoraphobia correlated more strongly with both the social phobia and blood phobia components than with either the physiological hyperarousal or the anxiety sensitivity components. These findings suggest that the association between panic attacks and agoraphobia warrants greater attention.

Crew factors in flight operations IX : effects of planned cockpit rest on crew performance and alertness in long-haul operations

DOT National Transportation Integrated Search

1994-07-01

This report is the ninth in a series on physiological and psychological effects of flight operations on flight crews, and on the operational significance of these effects. Long-haul flight operations often involve rapid multiple time-zone changes, sl...

Evaluation of the Physical Components in Algerian High-School Pupils (16-19 Years): Determination of the Somatotype in Relation to Choice of Sports Activity

ERIC Educational Resources Information Center

Sebbane, M.; Remaoun, M.; Harchaoui, Y.; Abdelkader, A.; Karrou, M.

2009-01-01

This study aims to explore the somatotype of Algerian high-school pupils of 16-19 years old. Various works in the field of sport have shown that athletic performance is a result of multiple factors that could be classified under psychological, physiological and physical. This last factor relates to the physical aspects. It gathers anthropometric…

Physiologic Dysfunction Scores and Cognitive Function Test Performance in United States Adults

PubMed Central

Kobrosly, Roni W; Seplaki, Christopher L; Jones, Courtney M; van Wijngaarden, Edwin

2013-01-01

Objective To investigate the relationship between a measure of cumulative physiologic dysfunction and specific domains of cognitive function. Methods We examined a summary score measuring physiological dysfunction, a multisystem measure of the body’s ability to effectively adapt to physical and psychological demands, in relation to cognitive function deficits in a population of 4511 adults aged 20 to 59 who participated in the third National Health and Nutrition Examination Survey (1988–1994). Measures of cognitive function comprised three domains: working memory, visuomotor speed, and perceptual-motor speed. ‘Physiologic dysfunction’ scores summarizing measures of cardiovascular, immunologic, kidney, and liver function were explored. We used multiple linear regression models to estimate associations between cognitive function measures and physiological dysfunction scores, adjusting for socioeconomic factors, test conditions, and self-reported health factors. Results We noted a dose-response relationship between physiologic dysfunction and working memory (coefficient = 0.207, 95% CI = (0.066, 0.348), p < 0.0001) that persisted after adjustment for all covariates (p = 0.03). We did not observe any significant relationships between dysfunction scores and visuomotor (p = 0.37) or perceptual-motor ability (p = 0.33). Conclusions Our findings suggest that multisystem physiologic dysfunction is associated with working memory. Future longitudinal studies are needed to clarify the underlying mechanisms and explore the persistency of this association into later life. We suggest that such studies should incorporate physiologic data, neuroendocrine parameters, and a wide range of specific cognitive domains. PMID:22155941

Antimicrobial Tolerance in Biofilms

PubMed Central

Stewart, Philip S.

2015-01-01

The tolerance of microorganisms in biofilms to antimicrobial agents is examined through a meta-analysis of literature data. A numerical tolerance factor comparing the rates of killing in the planktonic and biofilm states is defined to provide a quantitative basis for the analysis. Tolerance factors for biocides and antibiotics range over three orders of magnitude. This variation is not explained by taking into account the molecular weight of the agent, the chemistry of the agent, the substratum material, or the speciation of the microorganisms. Tolerance factors do depend on the areal cell density of the biofilm at the time of treatment and on the age of the biofilm as grown in a particular experimental system. This suggests that there is something that happens during biofilm maturation, either physical or physiological, that is essential for full biofilm tolerance. Experimental measurements of antimicrobial penetration times in biofilms range over orders of magnitude, with slower penetration (>12 min) observed for reactive oxidants and cationic molecules. These agents are retarded through the interaction of reaction, sorption, and diffusion. The specific physiological status of microbial cells in a biofilm contributes to antimicrobial tolerance. A conceptual framework for categorizing physiological cell states is discussed in the context of antimicrobial susceptibility. It is likely that biofilms harbor cells in multiple states simultaneously (e.g., growing, stress-adapted, dormant, inactive) and that this physiological heterogeneity is an important factor in the tolerance of the biofilm state. PMID:26185072

Within gut physiochemical variation does not correspond to distinct resident fungal and bacterial communities in the tree-killing xylophage, Anolophora glabripennis

USDA-ARS?s Scientific Manuscript database

Insect guts harbor diverse microbial assemblages that can be influenced by multiple factors, including gut physiology and interactions by the host with its environment. The Asian longhorned beetle (ALB; Anoplophora glabripennis) is an invasive tree–killing insect, which harbors a diverse consortium ...

Fall risk and incidence reduction in high risk individuals with multiple sclerosis: a pilot randomized control trial.

PubMed

Sosnoff, Jacob J; Moon, Yaejin; Wajda, Douglas A; Finlayson, Marcia L; McAuley, Edward; Peterson, Elizabeth W; Morrison, Steve; Motl, Robert W

2015-10-01

To determine the feasibility of three fall prevention programs delivered over 12 weeks among individuals with multiple sclerosis: (A) a home-based exercise program targeting physiological risk factors; (B) an educational program targeting behavioral risk factors; and (C) a combined exercise-and-education program targeting both factors. Randomized controlled trial. Home-based training with assessments at research laboratory. A total of 103 individuals inquired about the investigation. After screening, 37 individuals with multiple sclerosis who had fallen in the last year and ranged in age from 45-75 years volunteered for the investigation. A total of 34 participants completed postassessment following the 12-week intervention. Participants were randomly assigned into one of four conditions: (1) wait-list control (n = 9); (2) home-based exercise (n = 11); (3) education (n = 9); or (4) a combined exercise and education (n = 8) group. Before and after the 12-week interventions, participants underwent a fall risk assessment as determined by the physiological profile assessment and provided information on their fall prevention behaviors as indexed by the Falls Prevention Strategy Survey. Participants completed falls diaries during the three-months postintervention. A total of 34 participants completed postintervention testing. Procedures and processes were found to be feasible. Overall, fall risk scores were lower in the exercise groups (1.15 SD 1.31) compared with the non-exercise groups (2.04 SD 1.04) following the intervention (p < 0.01). There was no group difference in fall prevention behaviors (p > 0.05). Further examination of home-based exercise/education programs for reducing falls in individuals with multiple sclerosis is warranted. A total of 108 participants would be needed in a larger randomized controlled trial.ClinicalTrials.org #NCT01956227. © The Author(s) 2014.

Effect of multiple stress factors (thermal, nutritional and pregnancy type) on adaptive capability of native ewes under semi-arid environment.

PubMed

Dias E Silva, Tairon Pannunzio; Costa Torreão, Jacira Neves da; Torreão Marques, Carlo Aldrovandi; de Araújo, Marcos Jácome; Bezerra, Leílson Rocha; Kumar Dhanasekaran, Dinesh; Sejian, Veerasamy

2016-07-01

This study was conducted to evaluate the effect of multiple stress factors (thermal, nutritional and pregnancy type) on two different native track breeds of ewes as reflected by their adaptive capability under semi-arid environment. The multiple stressor experiment was conducted in twenty-four ewes (12 Santa Inês and 12 Morada Nova ewes). Both heat stress and pregnancy stress was common to all four groups. However, the animals were divided into further two groups within each breed on the basis of nutrition regimen. According the groupings were: Group 1 (Six Santa Ines ewes; heat stress; nutrition at 0.5% of BW; single pregnancy); Group 2 (Six Santa Ines ewes; heat stress; nutrition at 1.5% BW; twin pregnancy); groups Group 3 (Six Morada Nova ewes; heat stress; nutrition at 0.5% of BW; single pregnancy); Group 4 (Six Morada Nova ewes; heat stress; nutrition at 1.5% BW; twin pregnancy). All the animals in the experiment were pregnant. Heat stress was induced by exposing all animals to summer heat stress in outside environment while the nutritional regimen followed was at 0.5% and 1.5% level of body weight (BW) respectively in each breed. The experiment was conducted in a completely randomized design with two breeds, two nutritional treatments and two pregnancy types, 10 repetitions for physiological parameters and six for blood parameters, with repeated measures over time. Physiological parameters (respiratory rate, pulse rate and rectal temperature) were measured with the animals at rest in the morning and afternoon, 0600-0700 and 1300-1400h, respectively, every seven days. Blood samples were collected every 14d for determination of serum glucose, triglycerides, cholesterol, urea and creatinine. We found interaction effect between breed and pregnancy type on respiratory rate and rectal temperature with greater values in Santa Inês ewes than Morada Nova ewes. However, there was no significant fixed effect of pregnancy type and supplementation level on physiological responses of breeds. Environmental factor (period of the day) had influenced the physiological responses of ewes during all gestational period. Santa Inês ewes had greater serum glucose concentration at 105d and 120d of gestation compared to the Morada Nova ewes. Morada Nova ewes had greater concentrations of triglycerides, urea at 120d, 150d and also greater cholesterol at 105d, 135d and 150d of gestation compared with Santa Inês ewes. The present result indicates that thermal condition was most important factor that modified the physiological responses of ewes in a semi-arid tropical environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Functional Task Test: 1. Sensorimotor changes Associated with Postflight Alterations in Astronaut Functional Task Performance

NASA Technical Reports Server (NTRS)

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

Unpredictability of fighter pilots' g duration tolerance by anthropometric and physiological characteristics.

PubMed

Park, Myunghwan; Yoo, Seunghoon; Seol, Hyeongju; Kim, Cheonyoung; Hong, Youngseok

2015-04-01

While the factors affecting fighter pilots' G level tolerance have been widely accepted, the factors affecting fighter pilots' G duration tolerance have not been well understood. Thirty-eight subjects wearing anti-G suits were exposed to sustained high G forces using a centrifuge. The subjects exerted AGSM and decelerated the centrifuge when they reached the point of loss of peripheral vision. The G profile consisted of a +2.3 G onset rate, +7.3 G single plateau, and -1.6 G offset rate. Each subject's G tolerance time was recorded and the relationship between the tolerance time and the subject's anthropometric and physiological factors were analyzed. The mean tolerance time of the 38 subjects was 31.6 s, and the min and max tolerance times were 20 s and 58 s, respectively. The correlation analysis indicated that none of the factors had statistically significant correlations with the subjects' G duration tolerance. Stepwise multiple regression analysis showed that G duration tolerance was not dependent on any personal factors of the subjects. After the values of personal factors were simplified into 0 or 1, the t-test analysis showed that subjects' heights were inversely correlated with G duration tolerance at a statistically significant level. However, a logistic regression analysis suggested that the effect of the height factor to a pilot's G duration tolerance was too weak to be used as a predictor of a pilot's G tolerance. Fighter pilots' G duration tolerance could not be predicted by pilots' anthropometric and physiological factors.

Analysis of clinical risk factors associated with the prognosis of severe multiple-trauma patients with acute lung injury.

PubMed

Wu, Junsong; Sheng, Lei; Wang, Shenhua; Li, Qiang; Zhang, Mao; Xu, Shaowen; Gan, Jianxin

2012-09-01

Several clinical risk factors have been reported to be associated with the prognosis of acute lung injury (ALI). However, these studies have included a general trauma patient population, without singling out the severely injured multiple-trauma patient population. To identify the potential risk factors that could affect the prognosis of ALI in multiple-trauma patients and investigate the prognostic effects of certain risk factors among different patient subpopulations. In this retrospective cohort study, severely injured multiple-trauma patients with early onset of ALI from several trauma centers were studied. Potential risk factors affecting the prognosis of ALI were examined by univariate and multivariate logistic analyses. There were 609 multiple-trauma patients with ALI admitted to the emergency department and emergency intensive care unit during the study period. The nine risk factors that affected prognosis, as indicated by the unadjusted odds ratios with 95% confidence intervals, were the APACHE II (Acute Physiology and Chronic Health Evaluation II) score, duration of trauma, age, gastrointestinal hemorrhage, pulmonary contusion, disseminated intravascular coagulation (DIC), multiple blood transfusions in 6 h, Injury Severity Score (ISS), and aspiration of gastric contents. Specific risk factors also affected different patient subpopulations in different ways. Patients older than 65 years and with multiple (> 10 units) blood transfusions in the early stage after multiple trauma were found to be independent risk factors associated with deterioration of ALI. The other factors studied, including pulmonary contusion, APACHE II score ≥ 20, ISS ≥ 16, gastrointestinal hemorrhage, and aspiration of gastric contents, may predict the unfavorable prognosis of ALI in the early stage of trauma, with their effects attenuating in the later stage. Duration of trauma ≥ 1 h and the presence of DIC may also indicate unfavorable prognosis during the entire treatment period. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

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.;

A comparative study of students' performance in preclinical physiology assessed by multiple choice and short essay questions.

PubMed

Oyebola, D D; Adewoye, O E; Iyaniwura, J O; Alada, A R; Fasanmade, A A; Raji, Y

2000-01-01

This study was designed to compare the performance of medical students in physiology when assessed by multiple choice questions (MCQs) and short essay questions (SEQs). The study also examined the influence of factors such as age, sex, O/level grades and JAMB scores on performance in the MCQs and SEQs. A structured questionnaire was administered to 264 medical students' four months before the Part I MBBS examination. Apart from personal data of each student, the questionnaire sought information on the JAMB scores and GCE O' Level grades of each student in English Language, Biology, Chemistry, Physics and Mathematics. The physiology syllabus was divided into five parts and the students were administered separate examinations (tests) on each part. Each test consisted of MCQs and SEQs. The performance in MCQs and SEQs were compared. Also, the effects of JAMB scores and GCE O/level grades on the performance in both the MCQs and SEQs were assessed. The results showed that the students performed better in all MCQ tests than in the SEQs. JAMB scores and O' level English Language grade had no significant effect on students' performance in MCQs and SEQs. However O' level grades in Biology, Chemistry, Physics and Mathematics had significant effects on performance in MCQs and SEQs. Inadequate knowledge of physiology and inability to present information in a logical sequence are believed to be major factors contributing to the poorer performance in the SEQs compared with MCQs. In view of the finding of significant association between performance in MCQs and SEQs and GCE O/level grades in science subjects and mathematics, it was recommended that both JAMB results and the GCE results in the four O/level subjects above may be considered when selecting candidates for admission into the medical schools.

Urban plant physiology: adaptation-mitigation strategies under permanent stress.

PubMed

Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

2015-02-01

Urban environments that are stressful for plant function and growth will become increasingly widespread in future. In this opinion article, we define the concept of 'urban plant physiology', which focuses on plant responses and long term adaptations to urban conditions and on the capacity of urban vegetation to mitigate environmental hazards in urbanized settings such as air and soil pollution. Use of appropriate control treatments would allow for studies in urban environments to be comparable to expensive manipulative experiments. In this opinion article, we propose to couple two approaches, based either on environmental gradients or manipulated gradients, to develop the concept of urban plant physiology for assessing how single or multiple environmental factors affect the key environmental services provided by urban forests. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

PubMed

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

1992-09-01

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

Periodic Decrements in Retrieval of the Memory of Nonreinforcement as Reflected in Resistance to Extinction

ERIC Educational Resources Information Center

Holloway, Frank A.; Sturgis, Robert D.

1976-01-01

Investigates the nature of the rhythmic process mediating multiple retention deficits in rats, i.e., whether it was induced by a training procedure or based on a pre-existing physiological rhythm. Also concerns the mechanism of the rhythm's effect on retention performance, whether it affects performance factors per se or the retrieval of prior…

Effects of steering demand on lane keeping behaviour, self-reports, and physiology. A simulator study.

PubMed

Dijksterhuis, Chris; Brookhuis, Karel A; De Waard, Dick

2011-05-01

In this study a driving simulator was used to determine changes in mental effort in response to manipulations of steering demand. Changes in mental effort were assessed by using subjective effort ratings, physiology, and the standard deviation of the lateral position. Steering demand was increased by exposure to narrow lane widths and high density oncoming traffic while speed was fixed in all conditions to prevent a compensatory reaction. Results indicated that both steering demand factors influence mental effort expenditure and using multiple measures contributes to effort assessment. Application of these outcomes for adaptive automation is envisaged. Copyright © 2010 Elsevier Ltd. All rights reserved.

NASA SMART Probe: Breast Cancer Application

NASA Technical Reports Server (NTRS)

Mah, Robert W.; Norvig, Peter (Technical Monitor)

2000-01-01

There is evidence in breast cancer and other malignancies that the physiologic environment within a tumor correlates with clinical outcome. We are developing a unique percutaneous Smart Probe to be used at the time of needle biopsy of the breast. The Smart Probe will simultaneously measure multiple physiologic parameters within a breast tumor. Direct and indirect measurements of tissue oxygen levels, blood flow, pH, and tissue fluid pressure will be analyzed in real-time. These parameters will be interpreted individually and collectively by innovative neural network techniques using advanced intelligent software. The goals are 1) develop a pecutaneous Smart Probe with multiple sensor modalities and applying advanced Information Technologies to provide real time diagnostic information of the tissue at tip of the probe, 2) test the percutaneous Smart Probe in women with benign and malignant breast masses who will be undergoing surgical biopsy, 3) correlate probe sensor data with benign and malignant status of breast masses, 4) determine whether the probe can detect physiologic differences within a breast tumor, and its margins, and in adjacent normal breast tissue, 5) correlate probe sensor data with known prognostic factors for breast caner, including tumor size, tumor grade, axillary lymph node metastases, estrogen receptor and progesterone receptor status.

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

Resting heart rate, physiological stress and disadvantage in Aboriginal and Torres Strait Islander Australians: analysis from a cross-sectional study.

PubMed

Zhang, Alice; Hughes, Jaquelyne T; Brown, Alex; Lawton, Paul D; Cass, Alan; Hoy, Wendy; O'Dea, Kerin; Maple-Brown, Louise J

2016-02-11

Lower socioeconomic status has been linked to long-term stress, which can manifest in individuals as physiological stress. The aim was to explore the relationship between low socioeconomic status and physiological stress in Aboriginal and Torres Strait Islander Australians. Using data from the eGFR Study (a cross-sectional study of 634 Indigenous Australians in urban and remote areas of northern and central Australia), we examined associations between resting heart rate and demographic, socioeconomic, and biomedical factors. An elevated resting heart rate has been proposed as a measure of sustained stress activation and was used as a marker of physiological stress. Relationships were assessed between heart rate and the above variables using univariate and multiple regression analyses. We reported a mean resting heart rate of 74 beats/min in the cohort (mean age 45 years). On multiple regression analysis, higher heart rate was found to be independently associated with Aboriginal ethnicity, being a current smoker, having only primary level schooling, higher HbA1c and higher diastolic blood pressure (model R(2) 0.25). Elevated resting heart rate was associated with lower socioeconomic status and poorer health profile in Aboriginal and Torres Strait Islander Australians. Higher resting heart rate may be an indicator of stress and disadvantage in this population at high risk of chronic diseases.

Effects of the space flight environment on the immune system

NASA Technical Reports Server (NTRS)

Sonnenfeld, Gerald; Butel, Janet S.; Shearer, William T.

2003-01-01

Space flight conditions have a dramatic effect on a variety of physiologic functions of mammals, including muscle, bone, and neurovestibular function. Among the physiological functions that are affected when humans or animals are exposed to space flight conditions is the immune response. The focus of this review is on the function of the immune system in space flight conditions during actual space flights, as well as in models of space flight conditions on the earth. The experiments were carried out in tissue culture systems, in animal models, and in human subjects. The results indicate that space flight conditions alter cell-mediated immune responses, including lymphocyte proliferation and subset distribution, and cytokine production. The mechanism(s) of space flight-induced alterations in immune system function remain(s) to be established. It is likely, however, that multiple factors, including microgravity, stress, neuroendocrine factors, sleep disruption, and nutritional factors, are involved in altering certain functions of the immune system. Such alterations could lead to compromised defenses against infections and tumors.

Integrating Prospective Longitudinal Data: Modeling Personality and Health in the Terman Life Cycle and Hawaii Longitudinal Studies

PubMed Central

Kern, Margaret L.; Hampson, Sarah E.; Goldberg, Lewis R.; Friedman, Howard S.

2013-01-01

The present study used a collaborative framework to integrate two long-term prospective studies: the Terman Life Cycle Study and the Hawaii Personality and Health Longitudinal Study. Using a five-factor personality-trait framework, teacher assessments of child personality were rationally and empirically aligned to establish similar factor structures across samples. Comparable items related to adult self-rated health, education, and alcohol use were harmonized, and data were pooled on harmonized items. A structural model was estimated, allowing paths to differ by sample. Harmonized child personality factors were then used to examine markers of physiological dysfunction in the Hawaii sample and mortality risk in the Terman sample. Harmonized conscientiousness predicted less physiological dysfunction in the Hawaii sample and lower mortality risk in the Terman sample. These results illustrate how collaborative, integrative work with multiple samples offers the exciting possibility that samples from different cohorts and ages can be linked together to directly test lifespan theories of personality and health. PMID:23231689

Role of the protective antigen octamer in the molecular mechanism of anthrax lethal toxin stabilization in plasma

PubMed Central

Kintzer, Alexander F.; Sterling, Harry J.; Tang, Iok I.; Abdul-Gader, Ali; Miles, Andrew J.; Wallace, B. A.; Williams, Evan R.; Krantz, Bryan A.

2010-01-01

Anthrax is caused by strains of Bacillus anthracis that produce two key virulence factors, anthrax toxin (Atx) and a poly-γ-D-glutamic acid capsule. Atx is comprised of three-proteins: protective antigen (PA) and two enzymes, lethal factor (LF) and edema factor (EF). To disrupt cell function, these components must assemble into holotoxin complexes, which contain either a ring-shaped homooctameric or homoheptameric PA oligomer bound to multiple copies of either LF and/or EF, producing lethal toxin (LT), edema toxin, or mixtures thereof. Once a host cell endocytoses these complexes, PA converts into a membrane-inserted channel that translocates LF and EF into the cytosol. LT may assemble on host cell surfaces or extracellularly in plasma. We show that under physiological conditions in bovine plasma that LT complexes containing heptameric PA aggregate and inactivate more readily than LT complexes containing octameric PA. LT complexes containing octameric PA possess enhanced stability, channel forming activity, and macrophage cytotoxicity relative to those containing heptameric PA. Under physiological conditions, multiple biophysical probes reveal that heptameric PA can prematurely adopt the channel conformation, but octameric PA complexes remain in their soluble prechannel configuration allowing them to resist aggregation and inactivation. We conclude that PA may form an octameric oligomeric state as a means to produce a more stable and active LT complex that may circulate freely in the blood. PMID:20433851

Personal and contextual factors related to delayed HIV diagnosis among men who have sex with men

PubMed Central

Nelson, Kimberly M.; Thiede, Hanne; Jenkins, Richard A.; Carey, James W.; Hutcheson, Rebecca; Golden, Matthew R.

2014-01-01

Delayed HIV diagnosis among men who have sex with men (MSM) in the United States continues to be a significant personal and public health issue. Using qualitative and quantitative data from 75 recently tested, HIV-seropositive MSM (38 delayed and 37 non-delayed testers) we sought to further elucidate potential personal and contextual factors that may contribute to delayed HIV diagnosis among MSM. Our findings indicate MSM who experience multiple life stressors, whether personal or contextual, have an increased likelihood of delaying HIV diagnosis. Further, MSM experiencing multiple life stressors without the scaffolding of social support, stable mental health, and self-efficacy to engage in protective health behaviors may be particularly vulnerable to delaying diagnosis. Interventions targeting these factors as well as structural interventions targeting physiological and safety concerns are needed to help MSM handle their life stressors more effectively and seek HIV testing in a timelier manner. PMID:24694326

Using Infrared Thermography to Assess Emotional Responses to Infants

ERIC Educational Resources Information Center

Esposito, Gianluca; Nakazawa, Jun; Ogawa, Shota; Stival, Rita; Putnick, Diane L.; Bornstein, Marc H.

2015-01-01

Adult-infant interactions operate simultaneously across multiple domains and at multiple levels -- from physiology to behaviour. Unpackaging and understanding them, therefore, involve analysis of multiple data streams. In this study, we tested physiological responses and cognitive preferences for infant and adult faces in adult females and males.…

Inhibition of intracellular proteolysis in muscle cultures by multiplication-stimulating activity

NASA Technical Reports Server (NTRS)

Janeczko, Richard A.; Etlinger, Joseph D.

1984-01-01

The effects of the insulin-like growth factor, multiplication-stimulating activity (MSA), on chick myotube cultures are studied. The results indicate that MSA is an effective anabolic agent regulating protein metabolism and amino acid uptake, but not sugar transport. Similar size effects on protein metabolism and amino acid uptake in serum-free media were observed in parallel studies with insulin, although insulin levels well in excess of the normal physiological range are required to produce significant effects. It is suggested that there is a generally low insulin sensitivity in cultured chick myotubes relative to adult tissues.

Annual Research Review: All Mothers Are Not Created Equal--Neural and Psychobiological Perspectives on Mothering and the Importance of Individual Differences

ERIC Educational Resources Information Center

Barrett, Jennifer; Fleming, Alison S.

2011-01-01

Quality of mothering relies on the integrity of multiple physiological and behavioral systems and on two maternal factors, one proximal and one distal, that have a great impact on how a mother mothers: postpartum depression and early experiences. To mother appropriately requires the action of systems that regulate sensation, perception, affect,…

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.;

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.

Epigenetics: a lasting impression?

PubMed

Biddie, Simon C; Lightman, Stafford L

2011-02-01

Epigenetics is the term that has been classically used to describe inheritable nongenetic factors that regulate genes. Although these factors were originally thought to act in a long time domain only, it is now clear that they can also be highly dynamic, changing over minutes. Transcription factors, including the glucocorticoid, oestrogen and androgen receptors, interact with these epigenetic mechanisms in a very dynamic manner to modify transcription of genes and consequently contribute to physiological processes, health and disease. Modern usage of the term epigenetics encompasses both longer-term and transient changes and is relevant to multiple biological systems. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.

Ergonomics study on mobile phones for thumb physiology discomfort

NASA Astrophysics Data System (ADS)

Bendero, J. M. S.; Doon, M. E. R.; Quiogue, K. C. A.; Soneja, L. C.; Ong, N. R.; Sauli, Z.; Vairavan, R.

2017-09-01

The study was conducted on Filipino undergraduate college students and aimed to find out about the significant factors associated with mobile phone usage and its effect on thumb pain.A correlation-prediction analysisand Multiple Linear Regression was adopted and used as the main tool in determining the significant factors and coming up with predictive models on thumb related pain. With the use of the software Statistical Package for the Social Sciences or SPSS in conducting linear regression, 2 significant factors on thumb-related pain (percentage of time using portrait as screen orientation when text messaging, amount of time playing games using one hand in a day) were found.

[Construction and analysis of a monitoring system with remote real-time multiple physiological parameters based on cloud computing].

PubMed

Zhu, Lingyun; Li, Lianjie; Meng, Chunyan

2014-12-01

There have been problems in the existing multiple physiological parameter real-time monitoring system, such as insufficient server capacity for physiological data storage and analysis so that data consistency can not be guaranteed, poor performance in real-time, and other issues caused by the growing scale of data. We therefore pro posed a new solution which was with multiple physiological parameters and could calculate clustered background data storage and processing based on cloud computing. Through our studies, a batch processing for longitudinal analysis of patients' historical data was introduced. The process included the resource virtualization of IaaS layer for cloud platform, the construction of real-time computing platform of PaaS layer, the reception and analysis of data stream of SaaS layer, and the bottleneck problem of multi-parameter data transmission, etc. The results were to achieve in real-time physiological information transmission, storage and analysis of a large amount of data. The simulation test results showed that the remote multiple physiological parameter monitoring system based on cloud platform had obvious advantages in processing time and load balancing over the traditional server model. This architecture solved the problems including long turnaround time, poor performance of real-time analysis, lack of extensibility and other issues, which exist in the traditional remote medical services. Technical support was provided in order to facilitate a "wearable wireless sensor plus mobile wireless transmission plus cloud computing service" mode moving towards home health monitoring for multiple physiological parameter wireless monitoring.

Demographic and temporal variations in immunity and condition of polar bears (Ursus maritimus) from the southern Beaufort Sea

USGS Publications Warehouse

Neuman-Lee, Lorin; Terletzky, Patricia; Atwood, Todd C.; Gese, Eric; Smith, Geoffrey; Greenfield, Sydney; Pettit, John; French, Susannah

2017-01-01

Assessing the health and condition of animals in their natural environment can be problematic. Many physiological metrics, including immunity, are highly influenced by specific context and recent events to which researchers may be unaware. Thus, using a multifaceted physiological approach and a context-specific analysis encompassing multiple time scales can be highly informative. Ecoimmunological tools in particular can provide important indications to the health of animals in the wild. We collected blood and hair samples from free-ranging polar bears (Ursus maritimus) in the southern Beaufort Sea and examined the influence of sex, age, and reproductive status on metrics of immunity, stress, and body condition during 2013–2015. We examined metrics of innate immunity (bactericidal ability and lysis) and stress (hair cortisol, reactive oxygen species, and oxidative barrier), in relation to indices of body condition considered to be short term (urea to creatinine ratio; UC ratio) and long term (storage energy and body mass index). We found the factors of sex, age, and reproductive status of the bear were critical for interpreting different physiological metrics. Additionally, the metrics of body condition were important predictors for stress indicators. Finally, many of these metrics differed between years, illustrating the need to examine populations on a longer time scale. Taken together, this study demonstrates the complex relationship between multiple facets of physiology and how interpretation requires us to examine individuals within a specific context.

Multiple regression for physiological data analysis: the problem of multicollinearity.

PubMed

Slinker, B K; Glantz, S A

1985-07-01

Multiple linear regression, in which several predictor variables are related to a response variable, is a powerful statistical tool for gaining quantitative insight into complex in vivo physiological systems. For these insights to be correct, all predictor variables must be uncorrelated. However, in many physiological experiments the predictor variables cannot be precisely controlled and thus change in parallel (i.e., they are highly correlated). There is a redundancy of information about the response, a situation called multicollinearity, that leads to numerical problems in estimating the parameters in regression equations; the parameters are often of incorrect magnitude or sign or have large standard errors. Although multicollinearity can be avoided with good experimental design, not all interesting physiological questions can be studied without encountering multicollinearity. In these cases various ad hoc procedures have been proposed to mitigate multicollinearity. Although many of these procedures are controversial, they can be helpful in applying multiple linear regression to some physiological problems.

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.

How to define severely injured patients? -- an Injury Severity Score (ISS) based approach alone is not sufficient.

PubMed

Paffrath, Thomas; Lefering, Rolf; Flohé, Sascha

2014-10-01

Multiple injured patients, polytrauma or severely injured patients are terms used as synonyms in international literature describing injured patients with a high risk of mortality and cost consuming therapeutic demands. In order to advance the definition of these terms, we analysed a large trauma registry. In detail, we compared critically ill trauma patients first specified on a pure anatomical base according to the ISS or NISS, second in the original "polytrauma definition" with two body regions affected and finally all of them combined with a physiological component. Records that were collected in the TraumaRegister DGU(®) of the German Trauma Society (Deutsche Gesellschaft für Unfallchirurgie, DGU) between 1993 and 2011 (92,479 patients) were considered for this study. All patients with primary admission from scene with a minimum hospital stay of 48 h and an Injury Severity Score (ISS)≥ 16 were included. Pre-hospital and early admission data were used to determine physiological risk factors and calculate individual risk of death using the Revised Injury Severity Classification (RISC). 45,350 patients met inclusion criteria. The overall hospital mortality rate was 20.4%. The predicted mortality according to the RISC-Score was 21.6%. 36,897 patients (81.4%) had injuries in several body regions. The prevalence of the five physiological risk factors varied between 17% (high age) and 34% (unconsciousness). There were 17,617 patients (38.8%) without any risk factor present on admission, while 30.6% (n=13,890) of the patients had one and 30.5% (n=13,843) had two or more factors present. Patients with ISS ≥ 16 but no physiological risk factor present had a very low mortality rate of 3.1% (542 of 17,617). With an increasing number of physiological factors there was an almost linear increase in mortality up to an 86% rate in patients with all five factors present. The 'polytrauma' definition of Butcher and colleagues with AIS ≥ 3 in at least two different body regions would apply to only 56.2% of patients in the present group with ISS ≥ 16. The mortality in this subgroup is only marginally higher (21.8%; 5559 of 25,494) than in the group of patients with only one severely affected body region (18.5%; 3675 of 19,875). In our opinion the principle of sharpening an anatomically based definition by a defined physiological problem will help to specify the really critically ill trauma patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nursing workload in intensive care unit trauma patients: analysis of associated factors.

PubMed

Nogueira, Lilia de Souza; Domingues, Cristiane de Alencar; Poggetti, Renato Sérgio; de Sousa, Regina Marcia Cardoso

2014-01-01

From the perspective of nurses, trauma patients in the Intensive Care Unit (ICU) demand a high degree of nursing workload due to hemodynamic instability and the severity of trauma injuries. This study aims to identify the factors related to the high nursing workload required for trauma victims admitted to the ICU. This is a prospective, cross-sectional study using descriptive and correlation analyses, conducted with 200 trauma patients admitted to an ICU in the city of São Paulo, Brazil. The nursing workload was measured using the Nursing Activities Score (NAS). The distribution of the NAS values into tertiles led to the identification of two research groups: medium/low workload and high workload. The Chi-square, Fisher's exact, Mann-Whitney and multiple logistic regression tests were utilized for the analyses. The majority of patients were male (82.0%) and suffered blunt trauma (94.5%), with traffic accidents (57.5%) and falls (31.0%) being prevalent. The mean age was 40.7 years (± 18.6) and the mean NAS was 71.3% (± 16.9). Patient gender, the presence of pulmonary failure, the number of injured body regions and the risk of death according to the Simplified Acute Physiology Score II were factors associated with a high degree of nursing workload in the first 24 hours following admission to the ICU. Workload demand was higher in male patients with physiological instability and multiple severe trauma injuries who developed pulmonary failure.

Stress modulation of cellular metabolic sensors: interaction of stress from temperature and rainfall on the intertidal limpet Cellana toreuma.

PubMed

Dong, Yun-Wei; Han, Guo-Dong; Huang, Xiong-Wei

2014-09-01

In the natural environment, organisms are exposed to large variations in physical conditions. Quantifying such physiological responses is, however, often performed in laboratory acclimation studies, in which usually only a single factor is varied. In contrast, field acclimatization may expose organisms to concurrent changes in several environmental variables. The interactions of these factors may have strong effects on organismal function. In particular, rare events that occur stochastically and have relatively short duration may have strong effects. The present experiments studied levels of expression of several genes associated with cellular stress and metabolic regulation in a field population of limpet Cellana toreuma that encountered a wide range of temperatures plus periodic rain events. Physiological responses to these variable conditions were quantified by measuring levels of mRNA of genes encoding heat-shock proteins (Hsps) and metabolic sensors (AMPKs and Sirtuin 1). Our results reveal high ratios of individuals in upregulation group of stress-related gene expression at high temperature and rainy days, indicating the occurrence of stress from both prevailing high summer temperatures and occasional rainfall during periods of emersion. At high temperature, stress due to exposure to rainfall may be more challenging than heat stress alone. The highly variable physiological performances of limpets in their natural habitats indicate the possible differences in capability for physiological regulation among individuals. Our results emphasize the importance of studies of field acclimatization in unravelling the effects of environmental change on organisms, notably in the context of multiple changes in abiotic factors that are accompanying global change. © 2014 John Wiley & Sons Ltd.

Biological Risk in the Mexican Population at the Turn of the 21st Century

PubMed Central

Beltrán-Sánchez, Hiram; Crimmins, Eileen M.

2013-01-01

Mexico has experienced changes in its demographic and epidemiologic profile accompanied by recent changes in nutrition and income. Thus, the old and the young have experienced very different environments. Using data from the Mexican National Health Nutrition Survey 2006, we examine age and sex differences in physiological status and dysregulation and assess how socioeconomic factors associate with variability in biological indicators of health. Results indicate that young people have experienced better physical development as evidenced by their being taller and having less stunting. There is currently little under-nutrition in Mexico, but there is evidence of over-nutrition as indicated by high prevalence of overweight across the age range. Physiological dysregulation across multiple systems is higher in Mexicans than Americans across all ages. Mexicans have: higher levels of blood pressure, plasma glucose, and especially for women, dysregulated cholesterol and higher body weight. Low education is associated with both being stunted and overweight, and with adverse levels of HDL cholesterol and more physiological risk factors. Rural dwelling males are less likely to be overweight as are females living in poor states. Living in a poor state among females and having rural residence among males is associated with a higher number of high-risk factors. Overweight is a strong predictor of hypertension. Age differences in indicators of physiological development suggest that the epidemiological and demographic transitions in Mexico were accompanied by improved physical development; however, increases in nutrition may have reached a point of diminishing returns as Mexico switched from a state of under-nutrition to over-nutrition. PMID:23812952

The Functional Task Test (FTT): An Interdisciplinary Testing Protocol to Investigate the Factors Underlying Changes in Astronaut Functional Performance

NASA Technical Reports Server (NTRS)

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

Integrating prospective longitudinal data: modeling personality and health in the Terman Life Cycle and Hawaii Longitudinal Studies.

PubMed

Kern, Margaret L; Hampson, Sarah E; Goldberg, Lewis R; Friedman, Howard S

2014-05-01

The present study used a collaborative framework to integrate 2 long-term prospective studies: the Terman Life Cycle Study and the Hawaii Personality and Health Longitudinal Study. Within a 5-factor personality-trait framework, teacher assessments of child personality were rationally and empirically aligned to establish similar factor structures across samples. Comparable items related to adult self-rated health, education, and alcohol use were harmonized, and data were pooled on harmonized items. A structural model was estimated as a multigroup analysis. Harmonized child personality factors were then used to examine markers of physiological dysfunction in the Hawaii sample and mortality risk in the Terman sample. Harmonized conscientiousness predicted less physiological dysfunction in the Hawaii sample and lower mortality risk in the Terman sample. These results illustrate how collaborative, integrative work with multiple samples offers the exciting possibility that samples from different cohorts and ages can be linked together to directly test life span theories of personality and health. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

HIF-1 and ventilatory acclimatization to chronic hypoxia

PubMed Central

Powell, Frank L.; Fu, Zhenxing

2008-01-01

Ventilatory acclimatization to hypoxia (VAH) is a time-dependent increase in ventilation and ventilatory O2-sensitivity that involves plasticity in carotid body chemoreceptors and CNS respiratory centers. Hypoxia inducible factor-1α (HIF-1α) controls the expression of several genes that increase physiological O2 supply. Studies using transgenic mice show HIF-1α expression in the carotid bodies and CNS with chronic sustained and intermittent hypoxia is important for VAH. Other O2-sensitive transcription factors such as HIF-2α may be important for VAH by reducing metabolic O2 demands also. Specific gene targets of HIF-1α shown to be involved in VAH include erythropoietin, endothelin-1, neuronal nitric oxide synthase and tyrosine hydroxylase. Other HIF-1α targets that may be involved in VAH include vascular endothelial growth factor, heme oxygenase 1 and cytoglobin. Interactions between these multiple pathways and feedback control of HIF-1α expression from some of the targets support a complex and powerful role for HIF-1α in neural plasticity of physiological control circuits with chronic hypoxia. PMID:18708172

Cardiorespiratory control and cytokine profile in response to heat stress, hypoxia, and lipopolysaccharide (LPS) exposure during early neonatal period.

PubMed

McDonald, Fiona B; Chandrasekharan, Kumaran; Wilson, Richard J A; Hasan, Shabih U

2016-02-01

Sudden infant death syndrome (SIDS) is one of the most common causes of postneonatal infant mortality in the developed world. An insufficient cardiorespiratory response to multiple environmental stressors (such as prone sleeping positioning, overwrapping, and infection), during a critical period of development in a vulnerable infant, may result in SIDS. However, the effect of multiple risk factors on cardiorespiratory responses has rarely been tested experimentally. Therefore, this study aimed to quantify the independent and possible interactive effects of infection, hyperthermia, and hypoxia on cardiorespiratory control in rats during the neonatal period. We hypothesized that lipopolysaccharide (LPS) administration will negatively impact cardiorespiratory responses to increased ambient temperature and hypoxia in neonatal rats. Sprague-Dawley neonatal rat pups were studied at postnatal day 6-8. Rats were examined at an ambient temperature of 33°C or 38°C. Within each group, rats were allocated to control, saline, or LPS (200 μg/kg) treatments. Cardiorespiratory and thermal responses were recorded and analyzed before, during, and after a hypoxic exposure (10% O2). Serum samples were taken at the end of each experiment to measure cytokine concentrations. LPS significantly increased cytokine concentrations (such as TNFα, IL-1β, MCP-1, and IL-10) compared to control. Our results do not support a three-way interaction between experimental factors on cardiorespiratory control. However, independently, heat stress decreased minute ventilation during normoxia and increased the hypoxic ventilatory response. Furthermore, LPS decreased hypoxia-induced tachycardia. Herein, we provide an extensive serum cytokine profile under various experimental conditions and new evidence that neonatal cardiorespiratory responses are adversely affected by dual interactions of environmental stress factors. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

The physiological determinants of Sudden Infant Death Syndrome☆,☆☆

PubMed Central

Garcia, Alfredo J.; Koschnitzky, Jenna E.; Ramirez, Jan-Marino

2013-01-01

It is well-established that environmental and biological risk factors contribute to Sudden Infant Death Syndrome (SIDS). There is also growing consensus that SIDS requires the intersection of multiple risk factors that result in the failure of an infant to overcome cardio-respiratory challenges. Thus, the critical next steps in understanding SIDS are to unravel the physiological determinants that actually cause the sudden death, to synthesize how these determinants are affected by the known risk factors, and to develop novel ideas for SIDS prevention. In this review, we will examine current and emerging perspectives related to cardio-respiratory dysfunctions in SIDS. Specifically, we will review: (1) the role of the preBötzinger complex (preBötC) as a multi-functional network that is critically involved in the failure to adequately respond to hypoxic and hypercapnic challenges; (2) the potential involvement of the pre-BötC in the gender and age distributions that are characteristic for SIDS; (3) the link between SIDS and prematurity; and (4) the potential relationship between SIDS, auditory function, and central chemosensitivity. Each section underscores the importance of marrying the epidemiological and pathological data to experimental data in order to understand the physiological determinants of this syndrome. We hope that a better understanding will lead to novel ways to reduce the risk to succumb to SIDS. PMID:23735486

Physiological properties of brain-machine interface input signals.

PubMed

Slutzky, Marc W; Flint, Robert D

2017-08-01

Brain-machine interfaces (BMIs), also called brain-computer interfaces (BCIs), decode neural signals and use them to control some type of external device. Despite many experimental successes and terrific demonstrations in animals and humans, a high-performance, clinically viable device has not yet been developed for widespread usage. There are many factors that impact clinical viability and BMI performance. Arguably, the first of these is the selection of brain signals used to control BMIs. In this review, we summarize the physiological characteristics and performance-including movement-related information, longevity, and stability-of multiple types of input signals that have been used in invasive BMIs to date. These include intracortical spikes as well as field potentials obtained inside the cortex, at the surface of the cortex (electrocorticography), and at the surface of the dura mater (epidural signals). We also discuss the potential for future enhancements in input signal performance, both by improving hardware and by leveraging the knowledge of the physiological characteristics of these signals to improve decoding and stability. Copyright © 2017 the American Physiological Society.

Cardiomyocyte-released factors stimulate oligodendrocyte precursor cells proliferation

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

Kuroda, Mariko; Muramatsu, Rieko; Precursory Research for Embryonic Science and Technology

The heart produces multiple diffusible factors that are involved in a number of physiological processes, but the action of these factors on the central nervous system is not well understood. In this study, we found that one or more factors released by cardiomyocytes promote oligodendrocyte precursor cell (OPC) proliferation in vitro. Mouse OPCs co-cultured with mouse cardiomyocytes showed higher proliferative ability than OPCs cultured alone. In addition, cardiomyocyte-conditioned media was sufficient to promote OPC proliferation. The phosphorylation of phosphatidylinositol (PI) 3-kinase and extracellular signal-regulated kinase (ERK) in OPCs is necessary for the enhancement of OPC proliferation by cardiomyocyte-conditioned media. These datamore » indicate that heart-derived factors have the ability to directly regulate the function of central nervous system (CNS) cells.« less

A Pivotal Role of DELLAs in Regulating Multiple Hormone Signals.

PubMed

Davière, Jean-Michel; Achard, Patrick

2016-01-04

Plant phenotypic plasticity is controlled by diverse hormone pathways, which integrate and convey information from multiple developmental and environmental signals. Moreover, in plants many processes such as growth, development, and defense are regulated in similar ways by multiple hormones. Among them, gibberellins (GAs) are phytohormones with pleiotropic actions, regulating various growth processes throughout the plant life cycle. Previous work has revealed extensive interplay between GAs and other hormones, but the molecular mechanism became apparent only recently. Molecular and physiological studies have demonstrated that DELLA proteins, considered as master negative regulators of GA signaling, integrate multiple hormone signaling pathways through physical interactions with transcription factors or regulatory proteins from different families. In this review, we summarize the latest progress in GA signaling and its direct crosstalk with the main phytohormone signaling, emphasizing the multifaceted role of DELLA proteins with key components of major hormone signaling pathways. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

Identification and Evaluation of Integration and Cross Cutting Issues Across HRP Risks

NASA Technical Reports Server (NTRS)

Steinberg, S. L.; Shelhamer, Mark

2015-01-01

The HRP Integrated Research Plan contains the research plans for the 32 risks requiring research to characterize and mitigate. These risks to human health and performance in spaceflight are identified by evidence and each one focuses on a single aspect of human physiology or performance. They are further categorized by aspects of the spaceflight environment, such as altered gravity or space radiation, that that play a major role in their likelihood and consequence. From its inception the "integrate" in the Research Plan has denoted the integrated nature of risks to human health and performance, the connectedness of physiological systems within the human body regardless of the spaceflight environment, and the integrated response of the human body to the spaceflight environment. Common characteristics of the spaceflight environment include altered gravity, atmospheres and light/dark cycles, space radiation, isolation, noise, and periods of high or low workload. Long term exposure to this unique environment produces a suite of physiological effects such as stress; vision, neurocognitive and anthropometric changes; circadian misalignment; fluid shifts, deconditioning; immune dysregulation; and altered nutritional requirements. Matrix diagraming was used to systematically identify, analyze and rate the many-to-many relationships between environmental characteristics and the suite of physiological effects. It was also to identify patterns in the relationships of common physiological effects to each other. Analyses of patterns or relationships in these diagrams help to identify issues that cut across multiple risks. Cross cutting issues benefit from a multidisciplinary approach that synthesizes concepts or data from two or more disciplines to identify and characterize risk factors or develop countermeasures relevant to multiple risks. They also help to illuminate possible problem areas that may arise when a countermeasure impacts risks other than those which it was developed to mitigate, or identify groupings of physiological changes that are likely to occur that may impact the overall risk posture.

Systems identification and application systems development for monitoring the physiological and health status of crewmen in space

NASA Technical Reports Server (NTRS)

Leonard, J. I.; Furukawa, S.; Vannordstrand, P. C.

1975-01-01

The use of automated, analytical techniques to aid medical support teams is suggested. Recommendations are presented for characterizing crew health in terms of: (1) wholebody function including physiological, psychological and performance factors; (2) a combination of critical performance indexes which consist of multiple factors of measurable parameters; (3) specific responses to low noise level stress tests; and (4) probabilities of future performance based on present and periodic examination of past performance. A concept is proposed for a computerized real time biomedical monitoring and health care system that would have the capability to integrate monitored data, detect off-nominal conditions based on current knowledge of spaceflight responses, predict future health status, and assist in diagnosis and alternative therapies. Mathematical models could play an important role in this approach, especially when operating in a real time mode. Recommendations are presented to update the present health monitoring systems in terms of recent advances in computer technology and biomedical monitoring systems.

Epigenetics of reproductive infertility.

PubMed

Das, Laxmidhar; Parbin, Sabnam; Pradhan, Nibedita; Kausar, Chahat; Patra, Samir K

2017-06-01

Infertility is a complex pathophysiological condition. It may caused by specific or multiple physical and physiological factors, including abnormalities in homeostasis, hormonal imbalances and genetic alterations. In recent times various studies implicated that, aberrant epigenetic mechanisms are associated with reproductive infertility. There might be transgenerational effects associated with epigenetic modifications of gametes and studies suggest the importance of alterations in epigenetic modification at early and late stages of gametogenesis. To determine the causes of infertility it is necessary to understand the altered epigenetic modifications of associated gene and mechanisms involved therein. This review is devoted to elucidate the recent mechanistic advances in regulation of genes by epigenetic modification and emphasizes their possible role related to reproductive infertility. It includes environmental, nutritional, hormonal and physiological factors and influence of internal structural architecture of chromatin nucleosomes affecting DNA and histone modifications in both male and female gametes, early embryogenesis and offspring. Finally, we would like to emphasize that research on human infertility by gene knock out of epigenetic modifiers genes must be relied upon animal models.

Co-existence of multiple trade-off currencies shapes evolutionary outcomes

PubMed Central

Isaksson, Caroline; Salguero-Gómez, Roberto

2017-01-01

Evolutionary studies often assume that energy is the primary resource (i.e. “currency”) at the heart of the survival-reproduction trade-off, despite recent evidence to the contrary. The evolutionary consequences of having a single trade-off currency versus multiple competing currencies are unknown. Using simulations, we modeled the evolution of either a single physiological currency between reproduction and survival, or of multiple such currencies. For a wide array of model specifications varying functional forms and strengths of the trade-offs, we show that the presence of multiple currencies (e.g. nutrients, time) generally results in the evolution of higher lifetime reproductive success through partial circumvention of such trade-offs. Evolution of the underlying physiology is also more highly contingent with multiple currencies. These results challenge the paradigm of a single survival-reproduction trade-off as central to life history evolution, suggesting greater roles for physiological constraints and contingency, and implying potential selection for evolution of multiple trade-off currencies. PMID:29216275

The role of hypoxia-inducible factor-2 in digestive system cancers.

PubMed

Zhao, J; Du, F; Shen, G; Zheng, F; Xu, B

2015-01-15

Hypoxia is an all but ubiquitous phenomenon in cancers. Two known hypoxia-inducible factors (HIFs), HIF-1α and HIF-2α, primarily mediate the transcriptional response to hypoxia. Despite the high homology between HIF-1α and HIF-2α, emerging evidence suggests differences between both molecules in terms of transcriptional targets as well as impact on multiple physiological pathways and tumorigenesis. To date, much progress has been made toward understanding the roles of HIF-2α in digestive system cancers. Indeed, HIF-2α has been shown to regulate multiple aspects of digestive system cancers, including cell proliferation, angiogenesis and apoptosis, metabolism, metastasis and resistance to chemotherapy. These findings make HIF-2α a critical regulator of this malignant phenotype. Here we summarize the function of HIF-2 during cancer development as well as its contribution to tumorigenesis in digestive system malignancies.

The role of hypoxia-inducible factor-2 in digestive system cancers

PubMed Central

Zhao, J; Du, F; Shen, G; Zheng, F; Xu, B

2015-01-01

Hypoxia is an all but ubiquitous phenomenon in cancers. Two known hypoxia-inducible factors (HIFs), HIF-1α and HIF-2α, primarily mediate the transcriptional response to hypoxia. Despite the high homology between HIF-1α and HIF-2α, emerging evidence suggests differences between both molecules in terms of transcriptional targets as well as impact on multiple physiological pathways and tumorigenesis. To date, much progress has been made toward understanding the roles of HIF-2α in digestive system cancers. Indeed, HIF-2α has been shown to regulate multiple aspects of digestive system cancers, including cell proliferation, angiogenesis and apoptosis, metabolism, metastasis and resistance to chemotherapy. These findings make HIF-2α a critical regulator of this malignant phenotype. Here we summarize the function of HIF-2 during cancer development as well as its contribution to tumorigenesis in digestive system malignancies. PMID:25590810

Regulation of Ubiquitination-Mediated Protein Degradation by Survival Kinases in Cancer

PubMed Central

Yamaguchi, Hirohito; Hsu, Jennifer L.; Hung, Mien-Chie

2011-01-01

The ubiquitin–proteasome system is essential for multiple physiological processes via selective degradation of target proteins and has been shown to plays a critical role in human cancer. Activation of oncogenic factors and inhibition of tumor suppressors have been shown to be essential for cancer development, and protein ubiquitination has been linked to the regulation of oncogenic factors and tumor suppressors. Three kinases, AKT, extracellular signal-regulated kinase, and IκB kinase, we refer to as oncokinases, are activated in multiple human cancers. We and others have identified several key downstream targets that are commonly regulated by these oncokinases, some of which are regulated directly or indirectly via ubiquitin-mediated proteasome degradation, including FOXO3, β-catenin, myeloid cell leukemia-1, and Snail. In this review, we summarize these findings from our and other groups and discuss potential future studies and applications in the clinic. PMID:22649777

Improving treatment of neurodevelopmental disorders: recommendations based on preclinical studies.

PubMed

Homberg, Judith R; Kyzar, Evan J; Stewart, Adam Michael; Nguyen, Michael; Poudel, Manoj K; Echevarria, David J; Collier, Adam D; Gaikwad, Siddharth; Klimenko, Viktor M; Norton, William; Pittman, Julian; Nakamura, Shun; Koshiba, Mamiko; Yamanouchi, Hideo; Apryatin, Sergey A; Scattoni, Maria Luisa; Diamond, David M; Ullmann, Jeremy F P; Parker, Matthew O; Brown, Richard E; Song, Cai; Kalueff, Allan V

2016-01-01

Neurodevelopmental disorders (NDDs) are common and severely debilitating. Their chronic nature and reliance on both genetic and environmental factors makes studying NDDs and their treatment a challenging task. Herein, the authors discuss the neurobiological mechanisms of NDDs, and present recommendations on their translational research and therapy, outlined by the International Stress and Behavior Society. Various drugs currently prescribed to treat NDDs also represent a highly diverse group. Acting on various neurotransmitter and physiological systems, these drugs often lack specificity of action, and are commonly used to treat multiple other psychiatric conditions. There has also been relatively little progress in the development of novel medications to treat NDDs. Based on clinical, preclinical and translational models of NDDs, our recommendations cover a wide range of methodological approaches and conceptual strategies. To improve pharmacotherapy and drug discovery for NDDs, we need a stronger emphasis on targeting multiple endophenotypes, a better dissection of genetic/epigenetic factors or "hidden heritability," and a careful consideration of potential developmental/trophic roles of brain neurotransmitters. The validity of animal NDD models can be improved through discovery of novel (behavioral, physiological and neuroimaging) biomarkers, applying proper environmental enrichment, widening the spectrum of model organisms, targeting developmental trajectories of NDD-related behaviors and comorbid conditions beyond traditional NDDs. While these recommendations cannot be addressed all in once, our increased understanding of NDD pathobiology may trigger innovative cross-disciplinary research expanding beyond traditional methods and concepts.

Synergistic effects of abiotic stresses in plants: a case study of nitrogen limitation and saturating light intensity in Arabidopsis thaliana.

PubMed

Cohen, Itay; Rapaport, Tal; Chalifa-Caspi, Vered; Rachmilevitch, Shimon

2018-05-22

Under natural conditions, plants are regularly exposed to combinations of stress factors. A common example is the conjunction between nitrogen (N) deficiency and excess light. The combined effect of stress factors is often ignored in studies using controlled conditions, possibly resulting in misleading conclusions. To address this issue, the current study examined the physiological behavior of Arabidopsis thaliana under the effect of varying nitrogen levels and light intensities. The joint influence of low N and excess light had an adverse effect on plant growth, chlorophyll and anthocyanin concentrations, photochemical capacity, and the abundance of proteins involved in carbon assimilation and anti-oxidative metabolism. In contrast, no adverse physiological responses were observed for plants under either nitrogen limitation or high light intensity conditions (i.e., single stress). The underline mechanisms for the increased growth in conditions of high light and sufficient nitrogen was due to a combination of chlorophyll accumulation and an increased number of proteins involved in C3 carbon assimilation, amino acids biosynthesis and chloroplast development. In contrast, combined stress conditions caused anthocyanin accumulation and increased number proteins involved in catabolism of lipids and amino acids as energy substrates. Ultimately switching plants from growth to survival. Our results suggest that an assessment of the physiological response to the combined effect of multiple stresses cannot be directly extrapolated from the physiological response to a single stress. Specifically, the synergistic interaction between N deficiency and saturating light in Arabidopsis plants could not have been modeled via only one of the stress factors. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

SREBP-regulated lipid metabolism: convergent physiology - divergent pathophysiology.

PubMed

Shimano, Hitoshi; Sato, Ryuichiro

2017-12-01

Cellular lipid metabolism and homeostasis are controlled by sterol regulatory-element binding proteins (SREBPs). In addition to performing canonical functions in the transcriptional regulation of genes involved in the biosynthesis and uptake of lipids, genome-wide system analyses have revealed that these versatile transcription factors act as important nodes of convergence and divergence within biological signalling networks. Thus, they are involved in myriad physiological and pathophysiological processes, highlighting the importance of lipid metabolism in biology. Changes in cell metabolism and growth are reciprocally linked through SREBPs. Anabolic and growth signalling pathways branch off and connect to multiple steps of SREBP activation and form complex regulatory networks. In addition, SREBPs are implicated in numerous pathogenic processes such as endoplasmic reticulum stress, inflammation, autophagy and apoptosis, and in this way, they contribute to obesity, dyslipidaemia, diabetes mellitus, nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, chronic kidney disease, neurodegenerative diseases and cancers. This Review aims to provide a comprehensive understanding of the role of SREBPs in physiology and pathophysiology at the cell, organ and organism levels.

The Association between Discrimination and the Health of Sikh Asian Indians

PubMed Central

Nadimpalli, S.B.; Cleland, C.M.; Hutchinson, M.K.; Islam, N.; Barnes, L.L.; Van Devanter, N.

2015-01-01

Objective To investigate the relationships between self-reported discrimination (SRD) and mental and physical health (self-reported physical health conditions and direct, physiologic measures (BMI, waist-to-hip ratio, and blood pressure) among Sikh Asian Indians (AI), a group that may be particularly discriminated against due to physical manifestations of their faith, including a tendency to wear turbans or ethnic clothing. Methods Sikh AIs (N = 196) were recruited from Sikh gurdwaras in Queens, New York. Data were collected on SRD, social support and self-reported health, along with multiple direct physiological measures for cardiovascular health. Results Participants who wore turbans/scarves reported higher levels of discrimination than those who did not wear turbans/scarves. As hypothesized, multiple regression analysis supported that discrimination is significantly associated with poorer self-reported mental (B = −.53, p < .001) and physical health (B = −.16, p = .04) while controlling for socioeconomic, acculturation, and social support factors. The study did not support an association between SRD and physiologic measures (elevated BMI, waist-to-hip ratio, and blood pressure). Conclusion Consistent with previous discrimination and health reports, this study demonstrated an inverse relationship between discrimination and health among Sikh AIs, an understudied yet high risk minority population. Community-based efforts are also needed to reduce the occurrence or buffer the effects of discrimination experienced by Sikh AIs. PMID:27018726

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

PubMed

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

2016-01-19

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

Prediction of human core body temperature using non-invasive measurement methods.

PubMed

Niedermann, Reto; Wyss, Eva; Annaheim, Simon; Psikuta, Agnes; Davey, Sarah; Rossi, René Michel

2014-01-01

The measurement of core body temperature is an efficient method for monitoring heat stress amongst workers in hot conditions. However, invasive measurement of core body temperature (e.g. rectal, intestinal, oesophageal temperature) is impractical for such applications. Therefore, the aim of this study was to define relevant non-invasive measures to predict core body temperature under various conditions. We conducted two human subject studies with different experimental protocols, different environmental temperatures (10 °C, 30 °C) and different subjects. In both studies the same non-invasive measurement methods (skin temperature, skin heat flux, heart rate) were applied. A principle component analysis was conducted to extract independent factors, which were then used in a linear regression model. We identified six parameters (three skin temperatures, two skin heat fluxes and heart rate), which were included for the calculation of two factors. The predictive value of these factors for core body temperature was evaluated by a multiple regression analysis. The calculated root mean square deviation (rmsd) was in the range from 0.28 °C to 0.34 °C for all environmental conditions. These errors are similar to previous models using non-invasive measures to predict core body temperature. The results from this study illustrate that multiple physiological parameters (e.g. skin temperature and skin heat fluxes) are needed to predict core body temperature. In addition, the physiological measurements chosen in this study and the algorithm defined in this work are potentially applicable as real-time core body temperature monitoring to assess health risk in broad range of working conditions.

Crew Factors in Flight Operations. 11; A Survey of Fatigue Factors in Regional Airline Operations

NASA Technical Reports Server (NTRS)

Co, Elizabeth L.; Gregory, Kevin B.; Johnson, Julie M.; Rosekind, Mark R.

1999-01-01

This report is the eleventh in a series on the physiological effects of flight operations on flight crews. A 119-question survey was completed by 1,424 flight crewmembers from 26 regional carriers to identify factors contributing to fatigue in regional airline operations. Eighty-nine percent of crewmembers identified fatigue as a moderate or serious concern with 88% reporting that it was a common occurrence and 92% reporting that, when it occurs, fatigue represents a moderate or serious safety issue. However, 86% reported they received no company training addressing fatigue issues. Identified fatigue factors included multiple flight segments, scheduling considerations, varying regulations, and others. The two most commonly cited fatigue factors regarded flying multiple (more than four) segments. Scheduling factors accounted for nine of the ten most common recommendations to reduce fatigue in regional operations. Differing requirements among regulations were cited as contributing to fatigue. Other identified factors were the flight deck environment, automation, and diet. The data suggested specific recommendations, including education of industry personnel about fatigue issues and examination of scheduling practices. Education plays a critical role in any effort to address fatigue. Analyzing scheduling practices and identifying potential improvements may result in reduced fatigue as well as other benefits to operations.

Insulin/Insulin-like growth factor signaling controls non-Dauer developmental speed in the nematode Caenorhabditis elegans.

PubMed

Ruaud, Anne-Françoise; Katic, Iskra; Bessereau, Jean-Louis

2011-01-01

Identified as a major pathway controlling entry in the facultative dauer diapause stage, the DAF-2/Insulin receptor (InsR) signaling acts in multiple developmental and physiological regulation events in Caenorhabditis elegans. Here we identified a role of the insulin-like pathway in controlling developmental speed during the C. elegans second larval stage. This role relies on the canonical DAF-16/FOXO-dependent branch of the insulin-like signaling and is largely independent of dauer formation. Our studies provide further evidence for broad conservation of insulin/insulin-like growth factor (IGF) functions in developmental speed control.

Effect of prenatal programming on heifer development.

PubMed

Funston, Richard N; Summers, Adam F

2013-11-01

In beef cattle, the main factors influencing nutrient partitioning between the dam and fetus include age of the dam, number of fetuses, production demand, and environmental stress. These factors play a critical role in programming the fetus for its future environment and available resources. Fetal programming reportedly affects neonatal mortality and morbidity, postnatal growth rate, body composition, health, and reproduction. Two main mechanisms responsible for fetal programming include DNA methylation and histone modifications. Alterations in the genome can be passed through multiple generations. Maternal environment (nutrition, age, physiologic status) can program progeny heifer growth and reproductive performance. Copyright © 2013 Elsevier Inc. All rights reserved.

Effects of occupational stress on the gastrointestinal tract

PubMed Central

Huerta-Franco, María-Raquel; Vargas-Luna, Miguel; Tienda, Paola; Delgadillo-Holtfort, Isabel; Balleza-Ordaz, Marco; Flores-Hernandez, Corina

2013-01-01

The aim of this review is to provide a general overview of the relationship between occupational stress and gastrointestinal alterations. The International Labour Organization suggests occupational health includes psychological aspects to achieve mental well-being. However, the definition of health risks for an occupation includes biological, chemical, physical and ergonomic factors but does not address psychological stress or other affective disorders. Nevertheless, multiple investigations have studied occupational stress and its physiological consequences, focusing on specific risk groups and occupations considered stressful. Among the physiological effects of stress, gastrointestinal tract (GIT) alterations are highly prevalent. The relationship between occupational stress and GIT diseases is evident in everyday clinical practice; however, the usual strategy is to attack the effects but not the root of the problem. That is, in clinics, occupational stress is recognized as a source of GIT problems, but employers do not ascribe it enough importance as a risk factor, in general, and for gastrointestinal health, in particular. The identification, stratification, measurement and evaluation of stress and its associated corrective strategies, particularly for occupational stress, are important topics to address in the near future to establish the basis for considering stress as an important risk factor in occupational health. PMID:24244879

Modeling thermal sensation in a Mediterranean climate—a comparison of linear and ordinal models

NASA Astrophysics Data System (ADS)

Pantavou, Katerina; Lykoudis, Spyridon

2014-08-01

A simple thermo-physiological model of outdoor thermal sensation adjusted with psychological factors is developed aiming to predict thermal sensation in Mediterranean climates. Microclimatic measurements simultaneously with interviews on personal and psychological conditions were carried out in a square, a street canyon and a coastal location of the greater urban area of Athens, Greece. Multiple linear and ordinal regression were applied in order to estimate thermal sensation making allowance for all the recorded parameters or specific, empirically selected, subsets producing so-called extensive and empirical models, respectively. Meteorological, thermo-physiological and overall models - considering psychological factors as well - were developed. Predictions were improved when personal and psychological factors were taken into account as compared to meteorological models. The model based on ordinal regression reproduced extreme values of thermal sensation vote more adequately than the linear regression one, while the empirical model produced satisfactory results in relation to the extensive model. The effects of adaptation and expectation on thermal sensation vote were introduced in the models by means of the exposure time, season and preference related to air temperature and irradiation. The assessment of thermal sensation could be a useful criterion in decision making regarding public health, outdoor spaces planning and tourism.

[The acclimatization to extreme environments and its physiological mechanisms].

PubMed

Wang, Hai; Liu, Wei; Yang, Dan-Feng; Zhao, Xiao-Ling; Long, Chao-Liang; Yin, Zhao-Yun; Liu, Jia-Ying

2012-11-01

Acclimatization is a process of biological adaptation when exposed to environmental factors such as hypoxia, cold and heat for prolonged periods of time, where non-genetical variations play a role in allowing subjects to tolerate hypoxic, cold or hot environments. This review focuses on the characteristics and mechanisms of acclimatization found through major research advances by our institute. First, the mechanisms underlying the acclimatization to extreme environments are complex. In our investigations, the physiological changes of multiple systems including the nervous, circulatory, respiratory, and hemopoietic system were demonstrated when the acclimatization to hypoxia was developed, and the underlying significance of hypoxia-inducible factor-1 (HIF-1) was investigated. Second, it is suggested that the development of acclimatization to extreme environments is complicated. Hypoxia and cold coexist at high altitude. Our investigations revealed the characteristics of negative cross-relationship in the acclimatization to hypoxia and cold. And third, it is interesting for us to understand that acclimatization to extreme environments is transferable among individuals, and the characteristics of heat acclimatization-inducing factor (HAlF) were presented. The above findings will provide a theoretical guidance for protective operations and help to establish a solid foundation for future research related to acclimatization.

Genomic Methods for Clinical and Translational Pain Research

PubMed Central

Wang, Dan; Kim, Hyungsuk; Wang, Xiao-Min; Dionne, Raymond

2012-01-01

Pain is a complex sensory experience for which the molecular mechanisms are yet to be fully elucidated. Individual differences in pain sensitivity are mediated by a complex network of multiple gene polymorphisms, physiological and psychological processes, and environmental factors. Here, we present the methods for applying unbiased molecular-genetic approaches, genome-wide association study (GWAS), and global gene expression analysis, to help better understand the molecular basis of pain sensitivity in humans and variable responses to analgesic drugs. PMID:22351080

Sex-Based Differences in Physiology: What Should We Teach in the Medical Curriculum?

ERIC Educational Resources Information Center

Blair, Martha L.

2007-01-01

An abundance of recent research indicates that there are multiple differences between males and females both in normal physiology and in the pathophysiology of disease. The Refresher Course on Gender Differences in Physiology, sponsored by the American Physiological Society Education Committee at the 2006 Experimental Biology Meeting in San…

Multiple Choice Questions Can Be Designed or Revised to Challenge Learners' Critical Thinking

ERIC Educational Resources Information Center

Tractenberg, Rochelle E.; Gushta, Matthew M.; Mulroney, Susan E.; Weissinger, Peggy A.

2013-01-01

Multiple choice (MC) questions from a graduate physiology course were evaluated by cognitive-psychology (but not physiology) experts, and analyzed statistically, in order to test the independence of content expertise and cognitive complexity ratings of MC items. Integration of higher order thinking into MC exams is important, but widely known to…

Hypertension: physiology and pathophysiology.

PubMed

Hall, John E; Granger, Joey P; do Carmo, Jussara M; da Silva, Alexandre A; Dubinion, John; George, Eric; Hamza, Shereen; Speed, Joshua; Hall, Michael E

2012-10-01

Despite major advances in understanding the pathophysiology of hypertension and availability of effective and safe antihypertensive drugs, suboptimal blood pressure (BP) control is still the most important risk factor for cardiovascular mortality and is globally responsible for more than 7 million deaths annually. Short-term and long-term BP regulation involve the integrated actions of multiple cardiovascular, renal, neural, endocrine, and local tissue control systems. Clinical and experimental observations strongly support a central role for the kidneys in the long-term regulation of BP, and abnormal renal-pressure natriuresis is present in all forms of chronic hypertension. Impaired renal-pressure natriuresis and chronic hypertension can be caused by intrarenal or extrarenal factors that reduce glomerular filtration rate or increase renal tubular reabsorption of salt and water; these factors include excessive activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, increased formation of reactive oxygen species, endothelin, and inflammatory cytokines, or decreased synthesis of nitric oxide and various natriuretic factors. In human primary (essential) hypertension, the precise causes of impaired renal function are not completely understood, although excessive weight gain and dietary factors appear to play a major role since hypertension is rare in nonobese hunter-gathers living in nonindustrialized societies. Recent advances in genetics offer opportunities to discover gene-environment interactions that may also contribute to hypertension, although success thus far has been limited mainly to identification of rare monogenic forms of hypertension. © 2012 American Physiological Society

Military training elicits marked increases in plasma metabolomic signatures of energy metabolism, lipolysis, fatty acid oxidation, and ketogenesis.

PubMed

Karl, J Philip; Margolis, Lee M; Murphy, Nancy E; Carrigan, Christopher T; Castellani, John W; Madslien, Elisabeth H; Teien, Hilde-Kristin; Martini, Svein; Montain, Scott J; Pasiakos, Stefan M

2017-09-01

Military training studies provide unique insight into metabolic responses to extreme physiologic stress induced by multiple stressor environments, and the impacts of nutrition in mediating these responses. Advances in metabolomics have provided new approaches for extending current understanding of factors modulating dynamic metabolic responses in these environments. In this study, whole-body metabolic responses to strenuous military training were explored in relation to energy balance and macronutrient intake by performing nontargeted global metabolite profiling on plasma collected from 25 male soldiers before and after completing a 4-day, 51-km cross-country ski march that produced high total daily energy expenditures (25.4 MJ/day [SD 2.3]) and severe energy deficits (13.6 MJ/day [SD 2.5]). Of 737 identified metabolites, 478 changed during the training. Increases in 88% of the free fatty acids and 91% of the acylcarnitines, and decreases in 88% of the mono- and diacylglycerols detected within lipid metabolism pathways were observed. Smaller increases in 75% of the tricarboxylic acid cycle intermediates, and 50% of the branched-chain amino acid metabolites detected were also observed. Changes in multiple metabolites related to lipid metabolism were correlated with body mass loss and energy balance, but not with energy and macronutrient intakes or energy expenditure. These findings are consistent with an increase in energy metabolism, lipolysis, fatty acid oxidation, ketogenesis, and branched-chain amino acid catabolism during strenuous military training. The magnitude of the energy deficit induced by undereating relative to high energy expenditure, rather than macronutrient intake, appeared to drive these changes, particularly within lipid metabolism pathways. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Future Directions in Vulnerability to Depression among Youth: Integrating Risk Factors and Processes across Multiple Levels of Analysis

PubMed Central

Hankin, Benjamin L.

2014-01-01

Depression is a developmental phenomenon. Considerable progress has been made in describing the syndrome, establishing its prevalence and features, providing clues as to its etiology, and developing evidence-based treatment and prevention options. Despite considerable headway in distinct lines of vulnerability research, there is an explanatory gap in the field ability to more comprehensively explain and predict who is likely to become depressed, when, and why. Still, despite clear success in predicting moderate variance for future depression, especially with empirically rigorous methods and designs, the heterogeneous and multi-determined nature of depression suggests that additional etiologies need to be included to advance knowledge on developmental pathways to depression. This paper advocates for a multiple levels of analysis approach to investigating vulnerability to depression across the lifespan and providing a more comprehensive understanding of its etiology. One example of a multiple levels of analysis model of vulnerabilities to depression is provided that integrates the most accessible, observable factors (e.g., cognitive and temperament risks), intermediate processes and endophenotypes (e.g., information processing biases, biological stress physiology, and neural activation and connectivity), and genetic influences (e.g., candidate genes and epigenetics). Evidence for each of these factors as well as their cross-level integration is provided. Methodological and conceptual considerations important for conducting integrative, multiple levels of depression vulnerability research are discussed. Finally, translational implications for how a multiple levels of analysis perspective may confer additional leverage to reduce the global burden of depression and improve care are considered. PMID:22900513

Infectious Disease risks associated with exposure to stressful environments

NASA Technical Reports Server (NTRS)

Meehan, Ichard T.; Smith, Morey; Sams, Clarence

1993-01-01

Multiple environmental factors asociated with space flight can increase the risk of infectious illness among crewmembers thereby adversely affecting crew health and mission success. Host defences can be impaired by multiple physiological and psychological stressors including: sleep deprivation, disrupted circadian rhythms, separation from family, perceived danger, radiation exposure, and possibly also by the direct and indirect effects of microgravity. Relevant human immunological data from isolated or stressful environments including spaceflight will be reviewed. Long-duration missions should include reliable hardware which supports sophisticated immunodiagnostic capabilities. Future advances in immunology and molecular biology will continue to provide therapeutic agents and biologic response modifiers which should effectively and selectively restore immune function which has been depressed by exposure to environmental stressors.

The expanding universe of neurotrophic factors: therapeutic potential in aging and age-associated disorders.

PubMed

Lanni, C; Stanga, S; Racchi, M; Govoni, S

2010-01-01

Multiple molecular, cellular, structural and functional changes occur in the brain during aging. Neural cells may respond to these changes adaptively by employing multiple mechanisms in order to maintain the integrity of nerve cell circuits and to facilitate responses to environmental demands. Otherwise, they may succumb to neurodegenerative cascades that result in disorders such as Alzheimer's and Parkinson's diseases. An important role in this balancement is played by neurotrophic factors, which are central to many aspects of nervous system function since they regulate the development, maintenance and survival of neurons and neuron-supporting cells such as glia and oligodendrocytes. A vast amount of evidence indicates that alterations in levels of neurotrophic factors or their receptors can lead to neuronal death and contribute to aging as well as to the pathogenesis of diseases of abnormal trophic support (such as neurodegenerative diseases and depression) and diseases of abnormal excitability (such as epilepsy and central pain sensitization). Cellular and molecular mechanisms by which neurotrophic factors may influence cell survival and excitability are also critically examined to provide novel concepts and targets for the treatment of physiological changes bearing detrimental functional alterations and of different diseases affecting the central nervous system during aging.

The sigma factors of Bacillus subtilis.

PubMed Central

Haldenwang, W G

1995-01-01

The specificity of DNA-dependent RNA polymerase for target promotes is largely due to the replaceable sigma subunit that it carries. Multiple sigma proteins, each conferring a unique promoter preference on RNA polymerase, are likely to be present in all bacteria; however, their abundance and diversity have been best characterized in Bacillus subtilis, the bacterium in which multiple sigma factors were first discovered. The 10 sigma factors thus far identified in B. subtilis directly contribute to the bacterium's ability to control gene expression. These proteins are not merely necessary for the expression of those operons whose promoters they recognize; in many instances, their appearance within the cell is sufficient to activate these operons. This review describes the discovery of each of the known B. subtilis sigma factors, their characteristics, the regulons they direct, and the complex restrictions placed on their synthesis and activities. These controls include the anticipated transcriptional regulation that modulates the expression of the sigma factor structural genes but, in the case of several of the B. subtilis sigma factors, go beyond this, adding novel posttranslational restraints on sigma factor activity. Two of the sigma factors (sigma E and sigma K) are, for example, synthesized as inactive precursor proteins. Their activities are kept in check by "pro-protein" sequences which are cleaved from the precursor molecules in response to intercellular cues. Other sigma factors (sigma B, sigma F, and sigma G) are inhibited by "anti-sigma factor" proteins that sequester them into complexes which block their ability to form RNA polymerase holoenzymes. The anti-sigma factors are, in turn, opposed by additional proteins which participate in the sigma factors' release. The devices used to control sigma factor activity in B, subtilis may prove to be as widespread as multiple sigma factors themselves, providing ways of coupling sigma factor activation to environmental or physiological signals that cannot be readily joined to other regulatory mechanisms. PMID:7708009

Micropropagation of apple--a review.

PubMed

Dobránszki, Judit; da Silva, Jaime A Teixeira

2010-01-01

Micropropagation of apple has played an important role in the production of healthy, disease-free plants and in the rapid multiplication of scions and rootstocks with desirable traits. During the last few decades, in apple, many reliable methods have been developed for both rootstocks and scions from a practical, commercial point of view. Successful micropropagation of apple using pre-existing meristems (culture of apical buds or nodal segments) is influenced by several internal and external factors including ex vitro (e.g. genotype and physiological state) and in vitro conditions (e.g., media constituents and light). Specific requirements during stages of micropropagation, such as the establishment of in vitro cultures, shoot multiplication, rooting of microshoots and acclimatization are summarized in this review. New approaches for increasing shoot multiplication and rooting for apple and current use of micropropagated plantlets as tools in basic and applied research are also discussed.

Are Faculty Predictions or Item Taxonomies Useful for Estimating the Outcome of Multiple-Choice Examinations?

ERIC Educational Resources Information Center

Kibble, Jonathan D.; Johnson, Teresa

2011-01-01

The purpose of this study was to evaluate whether multiple-choice item difficulty could be predicted either by a subjective judgment by the question author or by applying a learning taxonomy to the items. Eight physiology faculty members teaching an upper-level undergraduate human physiology course consented to participate in the study. The…

Multiple Stressors in a Changing World: The Need for an Improved Perspective on Physiological Responses to the Dynamic Marine Environment.

PubMed

Gunderson, Alex R; Armstrong, Eric J; Stillman, Jonathon H

2016-01-01

Abiotic conditions (e.g., temperature and pH) fluctuate through time in most marine environments, sometimes passing intensity thresholds that induce physiological stress. Depending on habitat and season, the peak intensity of different abiotic stressors can occur in or out of phase with one another. Thus, some organisms are exposed to multiple stressors simultaneously, whereas others experience them sequentially. Understanding these physicochemical dynamics is critical because how organisms respond to multiple stressors depends on the magnitude and relative timing of each stressor. Here, we first discuss broad patterns of covariation between stressors in marine systems at various temporal scales. We then describe how these dynamics will influence physiological responses to multi-stressor exposures. Finally, we summarize how multi-stressor effects are currently assessed. We find that multi-stressor experiments have rarely incorporated naturalistic physicochemical variation into their designs, and emphasize the importance of doing so to make ecologically relevant inferences about physiological responses to global change.

Interactive effects on CO2, drought, and ultraviolet-B radiation on maize growth and development.

PubMed

Wijewardana, Chathurika; Henry, W Brien; Gao, Wei; Reddy, K Raja

2016-07-01

Crop growth and development are highly responsive to global climate change components such as elevated carbon dioxide (CO2), drought, and ultraviolet-B (UV-B) radiation. Plant tolerance to these environmental stresses comprises its genetic potential, physiological changes, metabolism, and signaling pathways. An inclusive understanding of morphological, physiological, and biochemical responses to these abiotic stresses is imperative for the development of stress tolerant varieties for future environments. The objectives of this study were to characterize the changes in vegetative and physiological traits in maize hybrids in their response to multiple environmental factors of (CO2) [400 and 750μmolmol(-1) (+(CO2)], irrigation treatments based evapotranspiration (ET) [100 and 50% (-ET)], and UV-B radiation [0 and 10kJm(-2)d(-1) (+UV-B)] and to identify the multiple stress tolerant hybrids aid in mitigating projected climate change for shaping future agriculture. Six maize hybrids (P1498, DKC 65-81, N75H-GTA, P1319, DKC 66-97, and N77P-3111) with known drought tolerance variability were grown in eight sunlit, controlled environment chambers in which control treatment consisted of 400μmolmol(-1) [CO2], 100% ET-based irrigation, and 0kJ UV-B. Plants grown at +UV-B alone or combination with 50% ET produced shorter plants and smaller leaf area while elevated CO2 treatments ameliorated the damaging effects of drought and higher UV-B levels on maize hybrids. Plant height, leaf area, total dry matter chlorophyll, carotenoids, and net photosynthesis measured were increased in response to CO2 enrichment. Total stress response index (TSRI) for each hybrid, developed from the cumulative sum of response indices of vegetative and physiological parameters, varied among the maize hybrids. The hybrids were classified as tolerant (P1498), intermediate (DKC 65-81, N75H-GTA, N77P-3111) and sensitive (P1319 and DKC 66-97) to multiple environmental stresses. The positive correlation between TSRI and vegetative and physiological index developed in this study demonstrates that a combination of vegetative and physiological traits is an effective screening tool to identify germplasm best suited to cope with future changing climates. Furthermore, the tolerant hybrids identified in this study indicate that the possibility of cultivar selection for enhanced agronomic performance and stability in a water limited environment with higher UV-B, anticipated to occur in future climates. Copyright © 2016 Elsevier B.V. All rights reserved.

Using Infrared Thermography to Assess Emotional Responses to Infants.

PubMed

Esposito, Gianluca; Nakazawa, Jun; Ogawa, Shota; Stival, Rita; Putnick, Diane L; Bornstein, Marc H

2015-01-01

Adult-infant interactions operate simultaneously across multiple domains and at multiple levels - from physiology to behavior. Unpackaging and understanding them, therefore, involves analysis of multiple data streams. In this study, we tested physiological responses and cognitive preferences for infant and adult faces in adult females and males. Infrared thermography was used to assess facial temperature changes as a measure of emotional valence, and we used a behavioral rating system to assess adults' expressed preferences. We found greater physiological activation in response to infant stimuli in females than males. As for cognitive preferences, we found greater responses to adult stimuli than to infant stimuli, both in males and females. The results are discuss in light of the Life History Theory. Finally, we discuss the importance of integrating the two data streams on our conclusions.

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

PubMed Central

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

2016-01-01

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

Platelet-rich plasma derived growth factors contribute to stem cell differentiation in musculoskeletal regeneration

NASA Astrophysics Data System (ADS)

Qian, Yun; Han, Qixin; Chen, Wei; Song, Jialin; Zhao, Xiaotian; Ouyang, Yuanming; Yuan, Weien; Fan, Cunyi

2017-10-01

Stem cell treatment and platelet-rich plasma (PRP) therapy are two significant issues in regenerative medicine. Stem cells such as bone marrow mesenchymal stem cells, adipose-derived stem cells and periodontal ligament stem cells can be successfully applied in the field of tissue regeneration. PRP, a natural product isolated from whole blood, can secrete multiple growth factors (GFs) for regulating physiological activities. These GFs can stimulate proliferation and differentiation of different stem cells in injury models. Therefore, combination of both agents receives wide expectations in regenerative medicine, especially in bone, cartilage and tendon repair. In this review, we thoroughly discussed the interaction and underlying mechanisms of platelet-rich plasma derived growth factors with stem cells, and assessed their functions in cell differentiation for musculoskeletal regeneration.

Design principles for therapeutic angiogenic materials

NASA Astrophysics Data System (ADS)

Briquez, Priscilla S.; Clegg, Lindsay E.; Martino, Mikaël M.; Gabhann, Feilim Mac; Hubbell, Jeffrey A.

2016-01-01

Despite extensive research, pro-angiogenic drugs have failed to translate clinically, and therapeutic angiogenesis, which has potential in the treatment of various cardiovascular diseases, remains a major challenge. Physiologically, angiogenesis — the process of blood-vessel growth from existing vasculature — is regulated by a complex interplay of biophysical and biochemical cues from the extracellular matrix (ECM), angiogenic factors and multiple cell types. The ECM can be regarded as the natural 3D material that regulates angiogenesis. Here, we leverage knowledge of ECM properties to derive design rules for engineering pro-angiogenic materials. We propose that pro-angiogenic materials should be biomimetic, incorporate angiogenic factors and mimic cooperative interactions between growth factors and the ECM. We highlight examples of material designs that demonstrate these principles and considerations for designing better angiogenic materials.

Home-based exercise program and fall-risk reduction in older adults with multiple sclerosis: phase 1 randomized controlled trial.

PubMed

Sosnoff, Jacob J; Finlayson, Marcia; McAuley, Edward; Morrison, Steve; Motl, Robert W

2014-03-01

To determine the feasibility, safety, and efficacy of a home-based exercise intervention targeting fall risk in older adults with multiple sclerosis. A randomized controlled pilot trial. A home-based exercise program. Participants were randomly allocated to either a home-based exercise intervention group (n = 13) or a waiting list control group (n = 14). The exercise group completed exercises targeting lower muscle strength and balance three times a week for 12 weeks. The control group continued normal activity. Fall risk (Physiological Profile Assessment scores), balance (Berg Balance Scale), and walking testing prior to and immediately following the 12-week intervention. Each outcome measure was placed in an analysis of covariance with group as the between-subject factor and baseline values as the covariate. Effect sizes were calculated. Twelve participants from the control group and ten from the exercise group completed the study. There were no related adverse events. Fall risk was found to decrease in the exercise group following the intervention (1.1 SD 1.0 vs. 0.6 SD 0.6) while there was an increase in fall risk in the control group (1.9 SD 1.5 vs. 2.2 SD 1.9). Effect sizes for most outcomes were large (η(2) > 0.15). Home-based exercise was found to be feasible, safe, and effective for reducing physiological fall risk in older adults with multiple sclerosis. Our findings support the implementation of a larger trial to reduce fall risk in persons with multiple sclerosis.

[Physical rehabilitation in multiple sclerosis: general principles and high-tech approaches].

PubMed

Peresedova, A V; Chernikova, L A; Zavalishin, I A

2013-01-01

In a chronic and disabling disease like multiple sclerosis, rehabilitation programs are of major importance for the preservation of physical, physiological, social and professional functioning and improvement of quality of life. Currently, it is generally assumed that physical activity is an important component of non-pharmacological rehabilitation in multiple sclerosis. Properly organized exercise is a safe and efficient way to induce improvements in a number of physiological functions. A multidisciplinary rehabilitative approach should be recommended. The main recommendations for the use of exercise for patients with multiple sclerosis have been listed. An important aspect of the modern physical rehabilitation in multiple sclerosis is the usage of high-tech methods. The published results of robot-assisted training to improve the hand function and walking impairment have been represented. An important trend in the rehabilitation of patients with multiple sclerosis is the reduction of postural disorders through training balance coordination. The role of transcranial magnetic stimulation in spasticity reducing is being investigated. The use of telemedicine capabilities is quite promising. Due to the fact that the decline in physical activity can lead to the deterioration of many aspects of physiological functions and, ultimately, to mobility decrease, further research of the role of physical rehabilitation as an important therapeutic approach in preventing the progression of disability in multiple sclerosis is required.

Can You Know Me Better? An Exploratory Study Combining Behavioural and Physiological Measurements for an Objective Assessment of Sensory Responsiveness in a Child with Profound Intellectual and Multiple Disabilities

ERIC Educational Resources Information Center

Lima, Mariely; Silva, Karine; Magalhaes, Ana; Amaral, Isabel; Pestana, Helena; de Sousa, Liliana

2012-01-01

Background: Sensory assessment of individuals with profound intellectual and multiple disabilities (PIMD) can be difficult for several reasons, including the idiosyncratic reactions that these individuals exhibit to environmental stimuli. This case report presents a combination of behavioural and physiological measurements aimed at providing an…

Functional Task Test: Data Review

NASA Technical Reports Server (NTRS)

Cromwell, Ronita

2014-01-01

After space flight there are changes in multiple physiological systems including: Cardiovascular function; Sensorimotor function; and Muscle function. How do changes in these physiological system impact astronaut functional performance?

Exploratory study of factors related to educational scores of first preclinical year medical students.

PubMed

Sitticharoon, Chantacha; Srisuma, Sorachai; Kanavitoon, Sawita; Summachiwakij, Sarayut

2014-03-01

The relationships among the scores of major subjects taught in the first preclinical year of a Thai medical school, previous academic achievements, and daily life activities are rarely explored. We therefore performed an exploratory study identifying various factors possibly related to the educational scores of these medical students. Questionnaires were sent out to all first preclinical year medical students, with 79.8% being returned (245/307 questionnaires). Positive correlations were revealed between the premedical year grade point average (pre-MD GPA) and anatomy, physiology, and biochemistry scores (R = 0.664, 0.521, and 0.653, respectively, P < 0.001 for all) by Pearson's method. Using multiple linear regression analysis, anatomy scores could be predicted by pre-MD GPA, student satisfaction with anatomy, the percentage of expected reading, monthly earnings, reading after class and near exam time, and duration of sleeping periods near exam time (R = 0.773, R(2) = 0.598, P < 0.001). Physiology scores could be estimated by pre-MD GPA, the percentage of expected reading, monthly earnings, and percentage of those who fell asleep during class and near exam time (R = 0.722, R(2) = 0.521, P < 0.001). Biochemistry scores could be calculated by pre-MD GPA, the percentage of expected reading, motivation to study medicine, student satisfaction with biochemistry, and exam performance expectations (R = 0.794, R(2) = 0.630, P < 0.001). In conclusion, pre-MD GPA and the percentage of expected reading are factors involved in producing good academic results in the first preclinical year. Anatomy and biochemistry, but not physiology, scores are influenced by satisfaction.

Multiple Component Event-Related Potential (mcERP) Estimation

NASA Technical Reports Server (NTRS)

Knuth, K. H.; Clanton, S. T.; Shah, A. S.; Truccolo, W. A.; Ding, M.; Bressler, S. L.; Trejo, L. J.; Schroeder, C. E.; Clancy, Daniel (Technical Monitor)

2002-01-01

We show how model-based estimation of the neural sources responsible for transient neuroelectric signals can be improved by the analysis of single trial data. Previously, we showed that a multiple component event-related potential (mcERP) algorithm can extract the responses of individual sources from recordings of a mixture of multiple, possibly interacting, neural ensembles. McERP also estimated single-trial amplitudes and onset latencies, thus allowing more accurate estimation of ongoing neural activity during an experimental trial. The mcERP algorithm is related to informax independent component analysis (ICA); however, the underlying signal model is more physiologically realistic in that a component is modeled as a stereotypic waveshape varying both in amplitude and onset latency from trial to trial. The result is a model that reflects quantities of interest to the neuroscientist. Here we demonstrate that the mcERP algorithm provides more accurate results than more traditional methods such as factor analysis and the more recent ICA. Whereas factor analysis assumes the sources are orthogonal and ICA assumes the sources are statistically independent, the mcERP algorithm makes no such assumptions thus allowing investigators to examine interactions among components by estimating the properties of single-trial responses.

Does stress induce bowel dysfunction?

PubMed

Chang, Yu-Ming; El-Zaatari, Mohamad; Kao, John Y

2014-08-01

Psychological stress is known to induce somatic symptoms. Classically, many gut physiological responses to stress are mediated by the hypothalamus-pituitary-adrenal axis. There is, however, a growing body of evidence of stress-induced corticotrophin-releasing factor (CRF) release causing bowel dysfunction through multiple pathways, either through the HPA axis, the autonomic nervous systems, or directly on the bowel itself. In addition, recent findings of CRF influencing the composition of gut microbiota lend support for the use of probiotics, antibiotics, and other microbiota-altering agents as potential therapeutic measures in stress-induced bowel dysfunction.

Orphan Nuclear Receptors as Targets for Drug Development

PubMed Central

Mukherjee, Subhajit

2012-01-01

Orphan nuclear receptors regulate diverse biological processes. These important molecules are ligand-activated transcription factors that act as natural sensors for a wide range of steroid hormones and xenobiotic ligands. Because of their importance in regulating various novel signaling pathways, recent research has focused on identifying xenobiotics targeting these receptors for the treatment of multiple human diseases. In this review, we will highlight these receptors in several physiologic and pathophysiologic actions and demonstrate how their functions can be exploited for the successful development of newer drugs. PMID:20372994

Novel NAC Transcription Factor TaNAC67 Confers Enhanced Multi-Abiotic Stress Tolerances in Arabidopsis

PubMed Central

Mao, Xinguo; Chen, Shuangshuang; Li, Ang; Zhai, Chaochao; Jing, Ruilian

2014-01-01

Abiotic stresses are major environmental factors that affect agricultural productivity worldwide. NAC transcription factors play pivotal roles in abiotic stress signaling in plants. As a staple crop, wheat production is severely constrained by abiotic stresses whereas only a few NAC transcription factors have been characterized functionally. To promote the application of NAC genes in wheat improvement by biotechnology, a novel NAC gene designated TaNAC67 was characterized in common wheat. To determine its role, transgenic Arabidopsis overexpressing TaNAC67-GFP controlled by the CaMV-35S promoter was generated and subjected to various abiotic stresses for morphological and physiological assays. Gene expression showed that TaNAC67 was involved in response to drought, salt, cold and ABA treatments. Localization assays revealed that TaNAC67 localized in the nucleus. Morphological analysis indicated the transgenics had enhanced tolerances to drought, salt and freezing stresses, simultaneously supported by enhanced expression of multiple abiotic stress responsive genes and improved physiological traits, including strengthened cell membrane stability, retention of higher chlorophyll contents and Na+ efflux rates, improved photosynthetic potential, and enhanced water retention capability. Overexpression of TaNAC67 resulted in pronounced enhanced tolerances to drought, salt and freezing stresses, therefore it has potential for utilization in transgenic breeding to improve abiotic stress tolerance in crops. PMID:24427285

Systematic correlation of environmental exposure and physiological and self-reported behaviour factors with leukocyte telomere length.

PubMed

Patel, Chirag J; Manrai, Arjun K; Corona, Erik; Kohane, Isaac S

2017-02-01

It is hypothesized that environmental exposures and behaviour influence telomere length, an indicator of cellular ageing. We systematically associated 461 indicators of environmental exposures, physiology and self-reported behaviour with telomere length in data from the US National Health and Nutrition Examination Survey (NHANES) in 1999-2002. Further, we tested whether factors identified in the NHANES participants are also correlated with gene expression of telomere length modifying genes. We correlated 461 environmental exposures, behaviours and clinical variables with telomere length, using survey-weighted linear regression, adjusting for sex, age, age squared, race/ethnicity, poverty level, education and born outside the USA, and estimated the false discovery rate to adjust for multiple hypotheses. We conducted a secondary analysis to investigate the correlation between identified environmental variables and gene expression levels of telomere-associated genes in publicly available gene expression samples. After correlating 461 variables with telomere length, we found 22 variables significantly associated with telomere length after adjustment for multiple hypotheses. Of these varaibales, 14 were associated with longer telomeres, including biomarkers of polychlorinated biphenyls([PCBs; 0.1 to 0.2 standard deviation (SD) increase for 1 SD increase in PCB level, P  < 0.002] and a form of vitamin A, retinyl stearate. Eight variables associated with shorter telomeres, including biomarkers of cadmium, C-reactive protein and lack of physical activity. We could not conclude that PCBs are correlated with gene expression of telomere-associated genes. Both environmental exposures and chronic disease-related risk factors may play a role in telomere length. Our secondary analysis found no evidence of association between PCBs/smoking and gene expression of telomere-associated genes. All correlations between exposures, behaviours and clinical factors and changes in telomere length will require further investigation regarding biological influence of exposure. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association

Misalignment with the external light environment drives metabolic and cardiac dysfunction.

PubMed

West, Alexander C; Smith, Laura; Ray, David W; Loudon, Andrew S I; Brown, Timothy M; Bechtold, David A

2017-09-12

Most organisms use internal biological clocks to match behavioural and physiological processes to specific phases of the day-night cycle. Central to this is the synchronisation of internal processes across multiple organ systems. Environmental desynchrony (e.g. shift work) profoundly impacts human health, increasing cardiovascular disease and diabetes risk, yet the underlying mechanisms remain unclear. Here, we characterise the impact of desynchrony between the internal clock and the external light-dark (LD) cycle on mammalian physiology. We reveal that even under stable LD environments, phase misalignment has a profound effect, with decreased metabolic efficiency and disrupted cardiac function including prolonged QT interval duration. Importantly, physiological dysfunction is not driven by disrupted core clock function, nor by an internal desynchrony between organs, but rather the altered phase relationship between the internal clockwork and the external environment. We suggest phase misalignment as a major driver of pathologies associated with shift work, chronotype and social jetlag.The misalignment between internal circadian rhythm and the day-night cycle can be caused by genetic, behavioural and environmental factors, and may have a profound impact on human physiology. Here West et al. show that desynchrony between the internal clock and the external environment alter metabolic parameters and cardiac function in mice.

Physiologic, demographic and mechanistic factors predicting New Injury Severity Score (NISS) in motor vehicle accident victims.

PubMed

Staff, T; Eken, T; Wik, L; Røislien, J; Søvik, S

2014-01-01

Current literature on motor vehicle accidents (MVAs) has few reports regarding field factors that predict the degree of injury. Also, studies of mechanistic factors rarely consider concurrent predictive effects of on-scene patient physiology. The New Injury Severity Score (NISS) has previously been found to correlate with mortality, need for ICU admission, length of hospital stay, and functional recovery after trauma. To potentially increase future precision of trauma triage, we assessed how the NISS is associated with physiologic, demographic and mechanistic variables from the accident site. Using mixed-model linear regression analyses, we explored the association between NISS and pre-hospital Glasgow Coma Scale (GCS) score, Revised Trauma Score (RTS) categories of respiratory rate (RR) and systolic blood pressure (SBP), gender, age, subject position in the vehicle, seatbelt use, airbag deployment, and the estimated squared change in vehicle velocity on impact ((Δv)(2)). Missing values were handled with multiple imputation. We included 190 accidents with 353 dead or injured subjects (mean NISS 17, median NISS 8, IQR 1-27). For the 307 subjects in front-impact MVAs, the mean increase in NISS was -2.58 per GCS point, -2.52 per RR category level, -2.77 per SBP category level, -1.08 for male gender, 0.18 per year of age, 4.98 for driver vs. rear passengers, 4.83 for no seatbelt use, 13.52 for indeterminable seatbelt use, 5.07 for no airbag deployment, and 0.0003 per (km/h)(2) velocity change (all p<0.002). This study in victims of MVAs demonstrated that injury severity (NISS) was concurrently and independently predicted by poor pre-hospital physiologic status, increasing age and female gender, and several mechanistic measures of localised and generalised trauma energy. Our findings underscore the need for precise information from the site of trauma, to reduce undertriage, target diagnostic efforts, and anticipate need for high-level care and rehabilitative resources. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dietary Phosphorus Intake and the Kidney

PubMed Central

Chang, Alex R.; Anderson, Cheryl

2017-01-01

Although phosphorus is an essential nutrient required for multiple physiological functions, recent research raises concerns that high phosphorus intake could have detrimental effects on health. Phosphorus is abundant in the food supply of developed countries, occurring naturally in protein-rich foods and as an additive in processed foods. High phosphorus intake can cause vascular and renal calcification, renal tubular injury, and premature death in multiple animal models. Small studies in human suggest that high phosphorus intake may result in positive phosphorus balance and correlate with renal calcification and albuminuria. Although serum phosphorus is strongly associated with cardiovascular disease, progression of kidney disease, and death, limited data exist linking high phosphorus intake directly to adverse clinical outcomes. Further prospective studies are needed to determine whether phosphorus intake is a modifiable risk factor for kidney disease. PMID:28613982

[Incidence of fall related injury in people aged 50 and above and risk factors in 8 provinces in China: a cross-sectional study].

PubMed

Guo, Y F; Ma, W J; Zhang, Q J; Yu, M; Xiao, Y Z; Guo, X L; Zhu, Y L; Liu, F; Ruan, Y; Sun, S Y; Huang, Z Z; Zheng, Y; Wu, F

2018-03-10

Objective: To estimate the incidence and distribution characteristics of fall related injury in people aged ≥50 years in 8 provinces in China and related physiological, psychological and social risk factors. Methods: Cross-sectional data were collected from adults aged ≥50 years participating in the World Health Organization (WHO) study on global ageing and adult health (SAGE) round 1 in China. Two-level hierarchical logistic model was used to identify the related factors for fall-related injury. All the models were stratified by living area (urban/rural). Results: Estimated incidence of fall related injury (road traffic injury was not included) was 3.2 %. Ageing and multiple chronic conditions ( OR =2.55, 95 %CI : 1.41-4.64) was significantly associated with the incidence of fall related injury in urban area. In rural area, depression ( OR =4.33, 95 % CI : 2.52-7.42) and multiple chronic conditions ( OR =2.46, 95 %CI : 1.37-4.41) were associated with the incidence of fall related injury. Conclusions: This study estimated the incidence of fall related injury in adults aged ≥50 years in 8 provinces in China. A significant association between multiple chronic conditions and fall related injury were found in both urban and rural residents. Targeted measures should be taken for the prevention and control of chronic diseases in elderly population.

The Nature of Self-Regulatory Fatigue and "Ego Depletion": Lessons From Physical Fatigue.

PubMed

Evans, Daniel R; Boggero, Ian A; Segerstrom, Suzanne C

2015-07-30

Self-regulation requires overriding a dominant response and leads to temporary self-regulatory fatigue. Existing theories of the nature and causes of self-regulatory fatigue highlight physiological substrates such as glucose, or psychological processes such as motivation, but these explanations are incomplete on their own. Historically, theories of physical fatigue demonstrate a similar pattern of useful but incomplete explanations, as recent views of physical fatigue emphasize the roles of both physiological and psychological factors. In addition to accounting for multiple inputs, these newer views also explain how fatigue can occur even in the presence of sufficient resources. Examining these newer theories of physical fatigue can serve as a foundation on which to build a more comprehensive understanding of self-regulatory fatigue that integrates possible neurobiological underpinnings of physical and self-regulatory fatigue, and suggests the possible function of self-regulatory fatigue. © 2015 by the Society for Personality and Social Psychology, Inc.

MicroRNAs and the metabolic hallmarks of aging.

PubMed

Victoria, Berta; Nunez Lopez, Yury O; Masternak, Michal M

2017-11-05

Aging, the natural process of growing older, is characterized by a progressive deterioration of physiological homeostasis at the cellular, tissue, and organismal level. Metabolically, the aging process is characterized by extensive changes in body composition, multi-tissue/multi-organ insulin resistance, and physiological declines in multiple signaling pathways including growth hormone, insulin/insulin-like growth factor 1, and sex steroids regulation. With this review, we intend to consolidate published information about microRNAs that regulate critical metabolic processes relevant to aging. In certain occasions we uncover relationships likely relevant to aging, which has not been directly described before, such as the miR-451/AMPK axis. We have also included a provocative section highlighting the potential role in aging of a new designation of miRNAs, namely fecal miRNAs, recently discovered to regulate intestinal microbiota in mammals. Copyright © 2016. Published by Elsevier B.V.

A multistressor, multitrait approach to assessing the effects of wind and dust on Eucalyptus tereticornis.

PubMed

Leonard, Ryan J; McArthur, Clare; Hochuli, Dieter F

2016-08-01

Plants are routinely subjected to multiple environmental stressors, and the ability to respond to these stressors determines species survival and ecological breadth. Despite stressors such as wind and dust significantly influencing plant development, morphology, and chemistry, the combined influence of these factors is yet to be investigated. We used a manipulative glasshouse approach to compare the morphological, physiological, and biomechanical responses of Eucalyptus tereticornis to the independent and combined effects of wind and dust. Wind decreased both E. tereticornis height and stem flexural stiffness. Additionally, wind had no effect on leaf physiology, nor did dust have any significant effect on any of the traits measured. Our results suggest that wind and dust in combination may have an additive effect on several plant traits and provide new insight into the effects and importance of studying wind, dust, and different stress combinations. © 2016 Botanical Society of America.

Principles and Guidelines for Duty and Rest Scheduling in Commercial Aviation

NASA Technical Reports Server (NTRS)

Dinges, David F.; Graeber, R. Curtis; Rosekind, Mark R.; Samel, Alexander

1996-01-01

The aviation industry requires 24-hour activities to meet operational demands. Growth in global long-haul, regional, overnight cargo, and short-haul domestic operations will continue to increase these round-the-clock requirements. Flight crews must be available to support 24-hour-a-day operations to meet these industry demands. Both domestic and international aviation can also require crossing multiple time zones. Therefore, shift work, night work, irregular work schedules, unpredictable work schedules, and dm zone changes will continue to be commonplace components of the aviation industry. These factors pose known challenges to human physiology, and because they result in performance-impairing fatigue, they pose a risk to safety. It is critical to acknowledge and, whenever possible, incorporate scientific information on fatigue, human sleep, and circadian physiology into 24-hour aviation operations. Utilization of such scientific information can help promote crew performance and alertness during flight operations and thereby maintain and improve the safety margin.

The nature of self-regulatory fatigue and “ego depletion”: Lessons from physical fatigue

PubMed Central

Evans, Daniel R.; Boggero, Ian A.; Segerstrom, Suzanne C.

2016-01-01

Self-regulation requires overriding a dominant response, and leads to temporary self-regulatory fatigue. Existing theories of the nature and causes of self-regulatory fatigue highlight physiological substrates such as glucose or psychological processes such as motivation, but these explanations are incomplete on their own. Historically, theories of physical fatigue demonstrate a similar pattern of useful but incomplete explanations, as recent views of physical fatigue emphasize the roles of both physiological and psychological factors. In addition to accounting for multiple inputs, these newer views also explain how fatigue can occur even in the presence of sufficient resources. Examining these newer theories of physical fatigue can serve as a foundation on which to build a more comprehensive understanding of self-regulatory fatigue that integrates possible neurobiological underpinnings of physical and self-regulatory fatigue, and suggests the possible function of self-regulatory fatigue. PMID:26228914

A Multi-Scale Sampling Strategy for Detecting Physiologically Significant Signals in AVIRIS Imagery

NASA Technical Reports Server (NTRS)

Gamon, John A.; Lee, Lai-Fun; Qiu, Hong-Lie; Davis, Stephen; Roberts, Dar A.; Ustin, Susan L.

1998-01-01

Models of photosynthetic production at ecosystem and global scales require multiple input parameters specifying physical and physiological surface features. While certain physical parameters (e.g., absorbed photosynthetically active radiation) can be derived from current satellite sensors, other physiologically relevant measures (e.g., vegetation type, water status, carboxylation capacity, or photosynthetic light-use efficiency), are not generally directly available from current satellite sensors at the appropriate geographic scale. Consequently, many model parameters must be assumed or derived from independent sources, often at an inappropriate scale. An abundance of ecophysiological studies at the leaf and canopy scales suggests strong physiological control of vegetation-atmosphere CO2 and water vapor fluxes, particularly in evergreen vegetation subjected to diurnal or seasonal stresses. For example hot, dry conditions can lead to stomatal closure, and associated "downregulation" of photosynthetic biochemical processes, a phenomenon often manifested as a "midday photosynthetic depression". A recent study with the revised simple biosphere (SiB2) model demonstrated that photosynthetic downregulation can significantly impact global climate. However, at the global scale, the exact significance of downregulation remains unclear, largely because appropriate physiological measures are generally unavailable at this scale. Clearly, there is a need to develop reliable ways of extracting physiologically relevant information from remote sensing. Narrow-band spectrometers offer many opportunities for deriving physiological parameters needed for ecosystem and global scale photosynthetic models. Experimental studies on the ground at the leaf- to stand-scale have indicated that several narrow-band features can be used to detect plant physiological status. One physiological signal is caused by xanthophyll cycle pigment activity, and is often expressed as the Photochemical Reflectance Index (PRI). Because the xanthophyll cycle pigments are photoregulatory pigments closely linked to photosynthetic function, this index can be used to derive relative photosynthetic rates. An additional signal with physiological significance is the 970 nm water absorption band, which provides a measure of liquid water content. This feature has been quantified both using a simple 2-band ratio (900/970 nm, here referred to as the "Water Band Index" or WBI;), and using the "continuum removal" method. Current atmospheric correction methods for AVIRIS imagery also obtain quantitative expressions of surface liquid water absorption based on the 970 nm water band and may be comparable to ground-based estimates of water content using this feature. However, physiological interpretations of both the PRI and the WBI are best understood at the leaf and canopy scales, where complications of atmospheric interference and complex stand and landscape features can be minimized, and where experimental manipulations can be readily applied. Currently it is not known whether these physiological indices can be used to derive meaningful physiological information from AVIRIS imagery. In addition to the problem of atmospheric interference, another challenge is that any simple physiological index can be confounded by multiple factors unrelated to physiology, and this problem can become more severe at progressively larger spatial scales. For example, previous work has suggested that both the PRI and the WBI, are strongly correlated with other optical measures of canopy structure (e.g., the Normalized Difference Vegetation Index or green vegetation fraction), indicating a confounding effect of structure on physiological signals at the larger, landscape scale. Furthermore, the normal operating mode of most imaging spectrometers does not allow simultaneous, ground truthing at a level of detail needed for physiological sampling. Additionally, manipulative experiments of physiology are difficult to apply at a geographic scale suitable for comparison with remote imagery, which often works at spatial scales that are several orders of magnitude larger than those typically used for physiological studies. These limitations require the consideration of alternative approaches to validating physiological information derived from AVIRIS data. In this report, we present a multi-scale sampling approach to detecting physiologically significant signals in narrow-band spectra. This approach explores the multi-dimensional data space provided by narrow-band spectrometry, and combines AVIRIS imagery at a large scale, with ground spectral sampling at an intermediate scale, and detailed ecophysiological measurements at a fine scale, to examine seasonally and spatially changing relationships between multiple structural and physiological variables. Examples of this approach are provided by simultaneous sampling of the Normalized Difference Vegetation Index (NDVI), an index of fractional PAR interception and green vegetation cover, the Water Band Index (WBI, an index of liquid water absorption, and the Photochemical Reflectance Index (PRI, an index of xanthophyll cycle pigment activity and photosynthetic light-use efficiency. By directly linking changing optical properties sampled on the ground with measurable physiological states, we hope to develop a basis for interpreting similar signals in AVIRIS imagery.

Physiological condition of juvenile wading birds in relation to multiple landscape stressors in the Florida Everglades: effects of hydrology, prey availability, and mercury bioaccumulation

USGS Publications Warehouse

Herring, Garth; Eagles-Smith, Collin A.; Gawlik, Dale E.; Beerens, James M.; Ackerman, Joshua T.

2014-01-01

The physiological condition of juvenile birds can be influenced by multiple ecological stressors, and few studies have concurrently considered the effects of environmental contaminants in combination with ecological attributes that can influence foraging conditions and prey availability. Using three temporally distinct indices of physiological condition, we compared the physiological response of nestling great egrets (Ardea alba) and white ibises (Eudocimus albus) to changing prey availability, hydrology (water depth, recession rate), and mercury exposure in the Florida Everglades. We found that the physiological response of chicks varied between species and among environmental variables. Chick body condition (short-term index) and fecal corticosterone levels (medium-term) were influenced by wetland water depth, prey availability, region, and age, but not by mercury contamination. However, mercury exposure did influence heat shock protein 70 (HSP70) in egret chicks, indicating a longer-term physiological response to contamination. Our results indicate that the physiological condition of egret and ibis chicks were influenced by several environmental stressors, and the time frame of the effect may depend on the specialized foraging behavior of the adults provisioning the chicks.

Physiological condition of juvenile wading birds in relation to multiple landscape stressors in the Florida Everglades: effects of hydrology, prey availability, and mercury bioaccumulation.

PubMed

Herring, Garth; Eagles-Smith, Collin A; Gawlik, Dale E; Beerens, James M; Ackerman, Joshua T

2014-01-01

The physiological condition of juvenile birds can be influenced by multiple ecological stressors, and few studies have concurrently considered the effects of environmental contaminants in combination with ecological attributes that can influence foraging conditions and prey availability. Using three temporally distinct indices of physiological condition, we compared the physiological response of nestling great egrets (Ardea alba) and white ibises (Eudocimus albus) to changing prey availability, hydrology (water depth, recession rate), and mercury exposure in the Florida Everglades. We found that the physiological response of chicks varied between species and among environmental variables. Chick body condition (short-term index) and fecal corticosterone levels (medium-term) were influenced by wetland water depth, prey availability, region, and age, but not by mercury contamination. However, mercury exposure did influence heat shock protein 70 (HSP70) in egret chicks, indicating a longer-term physiological response to contamination. Our results indicate that the physiological condition of egret and ibis chicks were influenced by several environmental stressors, and the time frame of the effect may depend on the specialized foraging behavior of the adults provisioning the chicks.

Physiological Condition of Juvenile Wading Birds in Relation to Multiple Landscape Stressors in the Florida Everglades: Effects of Hydrology, Prey Availability, and Mercury Bioaccumulation

PubMed Central

Herring, Garth; Eagles-Smith, Collin A.; Gawlik, Dale E.; Beerens, James M.; Ackerman, Joshua T.

2014-01-01

The physiological condition of juvenile birds can be influenced by multiple ecological stressors, and few studies have concurrently considered the effects of environmental contaminants in combination with ecological attributes that can influence foraging conditions and prey availability. Using three temporally distinct indices of physiological condition, we compared the physiological response of nestling great egrets (Ardea alba) and white ibises (Eudocimus albus) to changing prey availability, hydrology (water depth, recession rate), and mercury exposure in the Florida Everglades. We found that the physiological response of chicks varied between species and among environmental variables. Chick body condition (short-term index) and fecal corticosterone levels (medium-term) were influenced by wetland water depth, prey availability, region, and age, but not by mercury contamination. However, mercury exposure did influence heat shock protein 70 (HSP70) in egret chicks, indicating a longer-term physiological response to contamination. Our results indicate that the physiological condition of egret and ibis chicks were influenced by several environmental stressors, and the time frame of the effect may depend on the specialized foraging behavior of the adults provisioning the chicks. PMID:25184221

Physiologically relevant organs on chips

PubMed Central

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

2015-01-01

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

Age-Related Change in Mobility: Perspectives From Life Course Epidemiology and Geroscience

PubMed Central

Cooper, Rachel; Shardell, Michelle; Simonsick, Eleanor M.; Schrack, Jennifer A.; Kuh, Diana

2016-01-01

Mobility is the most studied and most relevant physical ability affecting quality of life with strong prognostic value for disability and survival. Natural selection has built the “engine” of mobility with great robustness, redundancy, and functional reserve. Efficient patterns of mobility can be acquired during development even by children affected by severe impairments. Analogously, age-associated impairments in mobility-related physiological systems are compensated and overt limitations of mobility only occur when the severity can no longer be compensated. Mobility loss in older persons usually results from multiple impairments in the central nervous system, muscles, joints, and energetic and sensory physiological systems. Early preclinical changes in these physiological systems that precede mobility loss have been poorly studied. Peak performance, rate of decline, compensatory behaviors, or subclinical deterioration of physiological resources may cumulatively influence both timing of mobility loss and chances of recovery, but their role as risk factors has not been adequately characterized. Understanding the natural history of these early changes and intervening on them would likely be the most effective strategy to reduce the burden of disability in the population. For example, young women with low bone peak mass could be counseled to start strength resistance exercise to reduce their high risk of developing osteoporosis and fracture later in life. Expanding this approach to other physiological domains requires collecting and interpreting data from life course epidemiological studies, establishing normative measures of mobility, physical function, and physical activity, and connecting them with life course trajectories of the mobility-relevant physiological domains. PMID:26975983

Diggin’ on U(biquitin): A Novel Method for the Identification of Physiological E3 Ubiquitin Ligase Substrates

PubMed Central

Rubel, Carrie E.; Schisler, Jonathan C.; Hamlett, Eric D.; DeKroon, Robert M.; Gautel, Mathias; Alzate, Oscar; Patterson, Cam

2013-01-01

The ubiquitin-proteasome system (UPS) plays a central role in maintaining protein homeostasis, emphasized by a myriad of diseases that are associated with altered UPS function such as cancer, muscle-wasting, and neurodegeneration. Protein ubiquitination plays a central role in both the promotion of proteasomal degradation as well as cellular signaling through regulation of the stability of transcription factors and other signaling molecules. Substrate specificity is a critical regulatory step of ubiquitination and is mediated by ubiquitin ligases. Recent studies implicate ubiquitin ligases in multiple models of cardiac diseases such as cardiac hypertrophy, atrophy, and ischemia/reperfusion injury, both in a cardioprotective and maladaptive role. Therefore, identifying physiological substrates of cardiac ubiquitin ligases provides both mechanistic insights into heart disease as well as possible therapeutic targets. Current methods identifying substrates for ubiquitin ligases rely heavily upon non-physiologic in vitro methods, impeding the unbiased discovery of physiological substrates in relevant model systems. Here we describe a novel method for identifying ubiquitin ligase substrates utilizing Tandem Ubiquitin Binding Entities (TUBE) technology, two-dimensional differential in gel electrophoresis (2-D DIGE), and mass spectrometry, validated by the identification of both known and novel physiological substrates of the ubiquitin ligase MuRF1 in primary cardiomyocytes. This method can be applied to any ubiquitin ligase, both in normal and disease model systems, in order to identify relevant physiological substrates under various biological conditions, opening the door to a clearer mechanistic understanding of ubiquitin ligase function and broadening their potential as therapeutic targets. PMID:23695782

Tubal telocytes: factor infertility reason?

PubMed

Aleksandrovych, Veronika; Sajewicz, Marek; Walocha, Jerzy A; Gil, Krzysztof

Infertility is actually widespread pathological condition, which affected one in every four couples in developing countries. Approximately one third of all cases are connected with tubal factor infertility, o en accompanies by endometriosis, acute salpingitis, urogenital infections etc. The newly identified telocytes (TCs) have multiple potential bio-functions and might participate in the fertility problems. They influence on structural and functional integrity of oviduct tissue. Despite recent discovery, TCs involvement in the majority of physiological and pathological processes is still unclear and require significant increasing of deep observations and data analysis. Focusing on female reproductive system help better understands the main reasons of infertility, while evaluation of TCs impact on Fallopian tube and uterus contractility might be a key point of its correction. The article summarizes the main features of telocytes in Fallopian tubes, emphasizing their involvement in pathophysiological processes and tubal factor infertility.

Is NF-kappaB a good target for cancer therapy? Hopes and pitfalls.

PubMed

Baud, Véronique; Karin, Michael

2009-01-01

Nuclear factor kappaB (NF-kappaB) transcription factors have a key role in many physiological processes such as innate and adaptive immune responses, cell proliferation, cell death, and inflammation. It has become clear that aberrant regulation of NF-kappaB and the signalling pathways that control its activity are involved in cancer development and progression, as well as in resistance to chemotherapy and radiotherapy. This article discusses recent evidence from cancer genetics and cancer genome studies that support the involvement of NF-kappaB in human cancer, particularly in multiple myeloma. The therapeutic potential and benefit of targeting NF-kappaB in cancer, and the possible complications and pitfalls of such an approach, are explored.

BIOLOGICAL AND BIOPHYSICAL PROPERTIES OF VASCULAR CONNEXIN CHANNELS

PubMed Central

Johnstone, Scott; Isakson, Brant; Locke, Darren

2010-01-01

Intercellular channels formed by connexin proteins play a pivotal role in the direct movement of ions and larger cytoplasmic solutes between vascular endothelial cells, between vascular smooth muscle cells, and between endothelial and smooth muscle cells. Multiple genetic and epigenetic factors modulate connexin expression levels and/or channel function, including cell type-independent and cell type-specific transcription factors, posttranslational modification and localized membrane targeting. Additionally, differences in protein-protein interactions, including those between connexins, significantly contribute to both vascular homeostasis and disease progression. The biophysical properties of the connexin channels identified in the vasculature, those formed by Cx37, Cx40, Cx43 and/or Cx45 proteins, are discussed in this review in the physiological and pathophysiological context of vessel function. PMID:19815177

Drosophila melanogaster as a model system for the evaluation of anti-aging compounds.

PubMed

Jafari, Mahtab

2010-01-01

Understanding the causes of aging is a complex problem due to the multiple factors that influence aging, which include genetics, environment, metabolism and reproduction, among others. These multiple factors create logistical difficulties in the evaluation of anti-aging agents. There is a need for good model systems to evaluate potential anti-aging compounds. The model systems used should represent the complexities of aging in humans, so that the findings may be extrapolated to human studies, but they should also present an opportunity to minimize the variables so that the experimental results can be accurately interpreted. In addition to positively affecting lifespan, the impact of the compound on the physiologic confounders of aging, including fecundity and the health span--the period of life where an organism is generally healthy and free from serious or chronic illness--of the model organism needs to be evaluated. Fecundity is considered a major confounder of aging in fruit flies. It is well established that female flies that are exposed to toxic substances typically reduce their dietary intake and their reproductive output and display an artifactual lifespan extension. As a result, drugs that achieve longevity benefits by reducing fecundity as a result of diminished food intake are probably not useful candidates for eventual treatment of aging in humans and should be eliminated during the screening process. Drosophila melanogaster provides a suitable model system for the screening of anti-aging compounds as D. melanogaster and humans have many conserved physiological and biological pathways. In this paper, I propose an algorithm to screen anti-aging compounds using Drosophila melanogaster as a model system.

Physiologically based pharmacokinetic model of amphotericin B disposition in rats following administration of deoxycholate formulation (Fungizone®): pooled analysis of published data.

PubMed

Kagan, Leonid; Gershkovich, Pavel; Wasan, Kishor M; Mager, Donald E

2011-06-01

The time course of tissue distribution of amphotericin B (AmB) has not been sufficiently characterized despite its therapeutic importance and an apparent disconnect between plasma pharmacokinetics and clinical outcomes. The goals of this work were to develop and evaluate a physiologically based pharmacokinetic (PBPK) model to characterize the disposition properties of AmB administered as deoxycholate formulation in healthy rats and to examine the utility of the PBPK model for interspecies scaling of AmB pharmacokinetics. AmB plasma and tissue concentration-time data, following single and multiple intravenous administration of Fungizone® to rats, from several publications were combined for construction of the model. Physiological parameters were fixed to literature values. Various structural models for single organs were evaluated, and the whole-body PBPK model included liver, spleen, kidney, lung, heart, gastrointestinal tract, plasma, and remainder compartments. The final model resulted in a good simultaneous description of both single and multiple dose data sets. Incorporation of three subcompartments for spleen and kidney tissues was required for capturing a prolonged half-life in these organs. The predictive performance of the final PBPK model was assessed by evaluating its utility in predicting pharmacokinetics of AmB in mice and humans. Clearance and permeability-surface area terms were scaled with body weight. The model demonstrated good predictions of plasma AmB concentration-time profiles for both species. This modeling framework represents an important basis that may be further utilized for characterization of formulation- and disease-related factors in AmB pharmacokinetics and pharmacodynamics.

Instrumentation for Non-Invasive Assessment of Cardiovascular Regulation

NASA Technical Reports Server (NTRS)

Cohen, Richard J.

1999-01-01

It is critically important to be able to assess alterations in cardiovascular regulation during and after space flight. We propose to develop an instrument for the non-invasive assessment of such alterations that can be used on the ground and potentially during space flight. This instrumentation would be used by the Cardiovascular Alterations Team at multiple sites for the study of the effects of space flight on the cardiovascular system and the evaluation of countermeasures. In particular, the Cardiovascular Alterations Team will use this instrumentation in conjunction with ground-based human bed-rest studies and during application of acute stresses e.g., tilt, lower body negative pressure, and exercise. In future studies, the Cardiovascular Alterations Team anticipates using this instrumentation to study astronauts before and after space flight and ultimately, during space flight. The instrumentation may also be used by the Bone Demineralization/Calcium Metabolism Team, the Neurovestibular Team and the Human Performance Factors, Sleep and Chronobiology Team to measure changes in autonomic nervous function. The instrumentation will be based on a powerful new technology - cardiovascular system identification (CSI) - which has been developed in our laboratory. CSI provides a non-invasive approach for the study of alterations in cardiovascular regulation. This approach involves the analysis of second-to-second fluctuations in physiologic signals such as heart rate and non-invasively measured arterial blood pressure in order to characterize quantitatively the physiologic mechanisms responsible for the couplings between these signals. Through the characterization of multiple physiologic mechanisms, CSI provides a closed-loop model of the cardiovascular regulatory state in an individual subject.

Genetics or environment in drug transport: the case of organic anion transporting polypeptides and adverse drug reactions.

PubMed

Clarke, John D; Cherrington, Nathan J

2012-03-01

Organic anion transporting polypeptide (OATP) uptake transporters are important for the disposition of many drugs and perturbed OATP activity can contribute to adverse drug reactions (ADRs). It is well documented that both genetic and environmental factors can alter OATP expression and activity. Genetic factors include single nucleotide polymorphisms (SNPs) that change OATP activity and epigenetic regulation that modify OATP expression levels. SNPs in OATPs contribute to ADRs. Environmental factors include the pharmacological context of drug-drug interactions and the physiological context of liver diseases. Liver diseases such as non-alcoholic fatty liver disease, cholestasis and hepatocellular carcinoma change the expression of multiple OATP isoforms. The role of liver diseases in the occurrence of ADRs is unknown. This article covers the roles OATPs play in ADRs when considered in the context of genetic or environmental factors. The reader will gain a greater appreciation for the current evidence regarding the salience and importance of each factor in OATP-mediated ADRs. A SNP in a single OATP transporter can cause changes in drug pharmacokinetics and contribute to ADRs but, because of overlap in substrate specificities, there is potential for compensatory transport by other OATP isoforms. By contrast, the expression of multiple OATP isoforms is decreased in liver diseases, reducing compensatory transport and thereby increasing the probability of ADRs. To date, most research has focused on the genetic factors in OATP-mediated ADRs while the impact of environmental factors has largely been ignored.

Functional capacity following univentricular repair--midterm outcome.

PubMed

Sen, Supratim; Bandyopadhyay, Biswajit; Eriksson, Peter; Chattopadhyay, Amitabha

2012-01-01

Previous studies have seldom compared functional capacity in children following Fontan procedure alongside those with Glenn operation as destination therapy. We hypothesized that Fontan circulation enables better midterm submaximal exercise capacity as compared to Glenn physiology and evaluated this using the 6-minute walk test. Fifty-seven children aged 5-18 years with Glenn (44) or Fontan (13) operations were evaluated with standard 6-minute walk protocols. Baseline SpO(2) was significantly lower in Glenn patients younger than 10 years compared to Fontan counterparts and similar in the two groups in older children. Postexercise SpO(2) fell significantly in Glenn patients compared to the Fontan group. There was no statistically significant difference in baseline, postexercise, or postrecovery heart rates (HRs), or 6-minute walk distances in the two groups. Multiple regression analysis revealed lower resting HR, higher resting SpO(2) , and younger age at latest operation to be significant determinants of longer 6-minute walk distance. Multiple regression analysis also established that younger age at operation, higher resting SpO(2) , Fontan operation, lower resting HR, and lower postexercise HR were significant determinants of higher postexercise SpO(2) . Younger age at operation and exercise, lower resting HR and postexercise HR, higher resting SpO(2) and postexercise SpO(2) , and dominant ventricular morphology being left ventricular or indeterminate/mixed had significant association with better 6-minute work on multiple regression analysis. Lower resting HR had linear association with longer 6-minute walk distances in the Glenn patients. Compared to Glenn physiology, Fontan operation did not have better submaximal exercise capacity assessed by walk distance or work on multiple regression analysis. Lower resting HR, higher resting SpO(2) , and younger age at operation were factors uniformly associated with better submaximal exercise capacity. © 2012 Wiley Periodicals, Inc.

Micropropagation of African violet (Saintpaulia ionantha Wendl.).

PubMed

Shukla, Mukund; Sullivan, J Alan; Jain, Shri Mohan; Murch, Susan J; Saxena, Praveen K

2013-01-01

Micropropagation is an important tool for rapid multiplication and the creation of genetic variability in African violets (Saintpaulia ionantha Wendl.). Successful in vitro propagation depends on the specific requirements and precise manipulation of various factors such as the type of explants used, physiological state of the mother plant, plant growth regulators in the culture medium, and growth conditions. Development of cost-effective protocols with a high rate of multiplication is a crucial requirement for commercial application of micropropagation. The current chapter describes an optimized protocol for micropropagation of African violets using leaf explants obtained from in vitro grown plants. In this process, plant regeneration occurs via both somatic embryogenesis and shoot organogenesis simultaneously in the explants induced with the growth regulator thidiazuron (TDZ; N-phenyl-N'-1,2,3-thidiazol-5-ylurea). The protocol is simple, rapid, and efficient for large-scale propagation of African violet and the dual routes of regeneration allow for multiple applications of the technology from simple clonal propagation to induction or selection of variants to the production of synthetic seeds.

Exogenous ascorbic acid improves defence responses of sunflower (Helianthus annuus) exposed to multiple stresses.

PubMed

Kaya, Armagan

2017-09-01

Ascorbic acid is an important antioxidant that plays role both on growth and development and also stress response of the plant. The purpose of this study was to determine the effect of ascorbate on physiological and biochemical changes of sunflower that was exposed to multiple stresses. Chlorophyll and carotenoid contents decreased and glutathione, ascorbate and malondialdehyde contents as well as antioxidant enzyme activities increased for sunflower plant that was exposed to 50 mM NaCl and pendimethalin at different concentrations. These changes were found to be more significant in groups simultaneously exposed to both stress factors. While malondialdehyde content decreased, chlorophyll, carotenoid, ascorbate, glutathione contents and antioxidant enzyme activities increased in plants treated exogenously with ascorbate, compared to the untreated samples. According to the findings of our study; compared to individual stress, the effect of stress is more pronounced in sunflower exposed to multiple stresses, and treatment with exogenous ascorbate reduces the negative effects of stress.

Human conditions of insulin-like growth factor-I (IGF-I) deficiency

PubMed Central

2012-01-01

Insulin-like growth factor I (IGF-I) is a polypeptide hormone produced mainly by the liver in response to the endocrine GH stimulus, but it is also secreted by multiple tissues for autocrine/paracrine purposes. IGF-I is partly responsible for systemic GH activities although it possesses a wide number of own properties (anabolic, antioxidant, anti-inflammatory and cytoprotective actions). IGF-I is a closely regulated hormone. Consequently, its logical therapeutical applications seems to be limited to restore physiological circulating levels in order to recover the clinical consequences of IGF-I deficiency, conditions where, despite continuous discrepancies, IGF-I treatment has never been related to oncogenesis. Currently the best characterized conditions of IGF-I deficiency are Laron Syndrome, in children; liver cirrhosis, in adults; aging including age-related-cardiovascular and neurological diseases; and more recently, intrauterine growth restriction. The aim of this review is to summarize the increasing list of roles of IGF-I, both in physiological and pathological conditions, underlying that its potential therapeutical options seem to be limited to those proven states of local or systemic IGF-I deficiency as a replacement treatment, rather than increasing its level upper the normal range. PMID:23148873

The effect of mechanical loads on the degradation of aliphatic biodegradable polyesters.

PubMed

Li, Ying; Chu, Zhaowei; Li, Xiaoming; Ding, Xili; Guo, Meng; Zhao, Haoran; Yao, Jie; Wang, Lizhen; Cai, Qiang; Fan, Yubo

2017-06-01

Aliphatic biodegradable polyesters have been the most widely used synthetic polymers for developing biodegradable devices as alternatives for the currently used permanent medical devices. The performances during biodegradation process play crucial roles for final realization of their functions. Because physiological and biochemical environment in vivo significantly affects biodegradation process, large numbers of studies on effects of mechanical loads on the degradation of aliphatic biodegradable polyesters have been launched during last decades. In this review article, we discussed the mechanism of biodegradation and several different mechanical loads that have been reported to affect the biodegradation process. Other physiological and biochemical factors related to mechanical loads were also discussed. The mechanical load could change the conformational strain energy and morphology to weaken the stability of the polymer. Besides, the load and pattern could accelerate the loss of intrinsic mechanical properties of polymers. This indicated that investigations into effects of mechanical loads on the degradation should be indispensable. More combination condition of mechanical loads and multiple factors should be considered in order to keep the degradation rate controllable and evaluate the degradation process in vivo accurately. Only then can the degradable devise achieve the desired effects and further expand the special applications of aliphatic biodegradable polyesters.

Operational Issues: What Science in Available?

NASA Technical Reports Server (NTRS)

Rosekind, Mark R.; Neri, David F.

1997-01-01

Flight/duty/rest considerations involve two highly complex factors: the diverse demands of aviation operations and human physiology (especially sleep and circadian rhythms). Several core operational issues related to fatigue have been identified, such as minimum rest requirements, duty length, flight time considerations, crossing multiple time zones, and night flying. Operations also can involve on-call reserve status and callout, delays due to unforeseen circumstances (e.g., weather, mechanical), and on-demand flights. Over 40 years of scientific research is now available to apply to these complex issues of flight/duty/rest requirements. This research involves controlled 'laboratory studies, simulations, and data collected during regular flight operations. When flight/duty/rest requirements are determined they are typically based on a variety of considerations, such as operational demand, safety, economic, etc. Rarely has the available, state-of-the-art science been a consideration along with these other factors when determining flight/duty/rest requirements. While the complexity of the operational demand and human physiology precludes an absolute solution, there is an opportunity to take full advantage of the current scientific data. Incorporating these data in a rational operational manner into flight/duty/rest requirements can improve flight crew performance, alertness, and ultimately, aviation safety.

Plasma granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor levels in critical illness including sepsis and septic shock: relation to disease severity, multiple organ dysfunction, and mortality.

PubMed

Presneill, J J; Waring, P M; Layton, J E; Maher, D W; Cebon, J; Harley, N S; Wilson, J W; Cade, J F

2000-07-01

To define the circulating levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) during critical illness and to determine their relationship to the severity of illness as measured by the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the development of multiple organ dysfunction, or mortality. Prospective cohort study. University hospital intensive care unit. A total of 82 critically ill adult patients in four clinically defined groups, namely septic shock (n = 29), sepsis without shock (n = 17), shock without sepsis (n = 22), and nonseptic, nonshock controls (n = 14). None. During day 1 of septic shock, peak plasma levels of G-CSF, interleukin (IL)-6, and leukemia inhibitory factor (LIF), but not GM-CSF, were greater than in sepsis or shock alone (p < .001), and were correlated among themselves (rs = 0.44-0.77; p < .02) and with the APACHE II score (rs = 0.25-0.40; p = .03 to .18). G-CSF, IL-6, and UF, and sepsis, shock, septic shock, and APACHE II scores were strongly associated with organ dysfunction or 5-day mortality by univariate analysis. However, multiple logistic regression analysis showed that only septic shock remained significantly associated with organ dysfunction and only APACHE II scores and shock with 5-day mortality. Similarly, peak G-CSF, IL-6, and LIF were poorly predictive of 30-day mortality. Plasma levels of G-CSF, IL-6, and LIF are greatly elevated in critical illness, including septic shock, and are correlated with one another and with the severity of illness. However, they are not independently predictive of mortality, or the development of multiple organ dysfunction. GM-CSF was rarely elevated, suggesting different roles for G-CSF and GM-CSF in human septic shock.

Multiple PAR and E4BP4 bZIP transcription factors in zebrafish: diverse spatial and temporal expression patterns.

PubMed

Ben-Moshe, Zohar; Vatine, Gad; Alon, Shahar; Tovin, Adi; Mracek, Philipp; Foulkes, Nicholas S; Gothilf, Yoav

2010-09-01

Circadian rhythms of physiology and behavior are generated by an autonomous circadian oscillator that is synchronized daily with the environment, mainly by light input. The PAR subfamily of transcriptional activators and the related E4BP4 repressor belonging to the basic leucine zipper (bZIP) family are clock-controlled genes that are suggested to mediate downstream circadian clock processes and to feedback onto the core oscillator. Here, the authors report the characterization of these genes in the zebrafish, an increasingly important model in the field of chronobiology. Five novel PAR and six novel e4bp4 zebrafish homolog genes were identified using bioinformatic tools and their coding sequences were cloned. Based on their evolutionary relationships, these genes were annotated as ztef2, zhlf1 and zhlf2, zdbp1 and zdbp2, and ze4bp4-1 to -6. The spatial and temporal mRNA expression pattern of each of these factors was characterized in zebrafish embryos in the context of a functional circadian clock and regulation by light. Nine of the factors exhibited augmented and rhythmic expression in the pineal gland, a central clock organ in zebrafish. Moreover, these genes were found to be regulated, to variable extents, by the circadian clock and/or by light. Differential expression patterns of multiple paralogs in zebrafish suggest multiple roles for these factors within the vertebrate circadian clock. This study, in the genetically accessible zebrafish model, lays the foundation for further research regarding the involvement and specific roles of PAR and E4BP4 transcription factors in the vertebrate circadian clock mechanism.

Vasoregression: A Shared Vascular Pathology Underlying Macrovascular And Microvascular Pathologies?

PubMed Central

Gupta, Akanksha

2015-01-01

Abstract Vasoregression is a common phenomenon underlying physiological vessel development as well as pathological microvascular diseases leading to peripheral neuropathy, nephropathy, and vascular oculopathies. In this review, we describe the hallmarks and pathways of vasoregression. We argue here that there is a parallel between characteristic features of vasoregression in the ocular microvessels and atherosclerosis in the larger vessels. Shared molecular pathways and molecular effectors in the two conditions are outlined, thus highlighting the possible systemic causes of local vascular diseases. Our review gives us a system-wide insight into factors leading to multiple synchronous vascular diseases. Because shared molecular pathways might usefully address the diagnostic and therapeutic needs of multiple common complex diseases, the literature analysis presented here is of broad interest to readership in integrative biology, rational drug development and systems medicine. PMID:26669709

The Role of Mammalian Sirtuins in the Regulation of Metabolism, Aging, and Longevity

PubMed Central

Satoh, Akiko; Stein, Liana

2013-01-01

Ever since the discovery of sirtuins a decade ago, interest in this family of NAD-dependent deacetylases has exploded, generating multiple lines of evidence implicating sirtuins as evolutionarily conserved regulators of lifespan. In mammals, it has been established that sirtuins regulate physiological responses to metabolism and stress, two key factors that affect the process of aging. Further investigation into the intimate connection among sirtuins, metabolism, and aging has implicated the activation of SIRT1 as both preventative and therapeutic measures against multiple age-associated disorders including type 2 diabetes and Alzheimer’s disease. SIRT1 activation has clear potential to not only prevent age-associated diseases but also to extend healthspan and perhaps lifespan. Sirtuin activating compounds and NAD intermediates are two promising ways to achieve these elusive goals. PMID:21879449

Anatomy and Physiology of Multiscale Modeling and Simulation in Systems Medicine.

PubMed

Mizeranschi, Alexandru; Groen, Derek; Borgdorff, Joris; Hoekstra, Alfons G; Chopard, Bastien; Dubitzky, Werner

2016-01-01

Systems medicine is the application of systems biology concepts, methods, and tools to medical research and practice. It aims to integrate data and knowledge from different disciplines into biomedical models and simulations for the understanding, prevention, cure, and management of complex diseases. Complex diseases arise from the interactions among disease-influencing factors across multiple levels of biological organization from the environment to molecules. To tackle the enormous challenges posed by complex diseases, we need a modeling and simulation framework capable of capturing and integrating information originating from multiple spatiotemporal and organizational scales. Multiscale modeling and simulation in systems medicine is an emerging methodology and discipline that has already demonstrated its potential in becoming this framework. The aim of this chapter is to present some of the main concepts, requirements, and challenges of multiscale modeling and simulation in systems medicine.

Physiologically relevant organs on chips.

PubMed

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

2014-01-01

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

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.

Drowsiness detection during different times of day using multiple features.

PubMed

Sahayadhas, Arun; Sundaraj, Kenneth; Murugappan, Murugappan

2013-06-01

Driver drowsiness has been one of the major causes of road accidents that lead to severe trauma, such as physical injury, death, and economic loss, which highlights the need to develop a system that can alert drivers of their drowsy state prior to accidents. Researchers have therefore attempted to develop systems that can determine driver drowsiness using the following four measures: (1) subjective ratings from drivers, (2) vehicle-based measures, (3) behavioral measures and (4) physiological measures. In this study, we analyzed the various factors that contribute towards drowsiness. A total of 15 male subjects were asked to drive for 2 h at three different times of the day (00:00-02:00, 03:00-05:00 and 15:00-17:00 h) when the circadian rhythm is low. The less intrusive physiological signal measurements, ECG and EMG, are analyzed during this driving task. Statistically significant differences in the features of ECG and sEMG signals were observed between the alert and drowsy states of the drivers during different times of day. In the future, these physiological measures can be fused with vision-based measures for the development of an efficient drowsiness detection system.

Genetic and physiological bases for phenological responses to current and predicted climates

PubMed Central

Wilczek, A. M.; Burghardt, L. T.; Cobb, A. R.; Cooper, M. D.; Welch, S. M.; Schmitt, J.

2010-01-01

We are now reaching the stage at which specific genetic factors with known physiological effects can be tied directly and quantitatively to variation in phenology. With such a mechanistic understanding, scientists can better predict phenological responses to novel seasonal climates. Using the widespread model species Arabidopsis thaliana, we explore how variation in different genetic pathways can be linked to phenology and life-history variation across geographical regions and seasons. We show that the expression of phenological traits including flowering depends critically on the growth season, and we outline an integrated life-history approach to phenology in which the timing of later life-history events can be contingent on the environmental cues regulating earlier life stages. As flowering time in many plants is determined by the integration of multiple environmentally sensitive gene pathways, the novel combinations of important seasonal cues in projected future climates will alter how phenology responds to variation in the flowering time gene network with important consequences for plant life history. We discuss how phenology models in other systems—both natural and agricultural—could employ a similar framework to explore the potential contribution of genetic variation to the physiological integration of cues determining phenology. PMID:20819808

Listening to hypochondriasis and hearing health anxiety.

PubMed

Braddock, Autumn E; Abramowitz, Jonathan S

2006-09-01

Although hypochondriasis is categorized as a somatoform disorder in the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition--Text Revision (DSM-IV-TR) due to excessive focus on bodily symptoms for at least 6 months, a contemporary conceptualization suggests that hypochondriasis represents an intense form of health anxiety. This article discusses the clinical presentation of hypochondriasis, etiological underpinnings and multiple maintaining factors, including physiological, cognitive and behavioral components. A cognitive-behavioral model of hypochondriasis as health anxiety and the empirically supported treatment based on the model are articulated. Future directions and informational resources are provided for both clinicians and patients.

Dynamic transcriptomic m6A decoration: writers, erasers, readers and functions in RNA metabolism.

PubMed

Yang, Ying; Hsu, Phillip J; Chen, Yu-Sheng; Yang, Yun-Gui

2018-05-22

N 6 -methyladenosine (m 6 A) is a chemical modification present in multiple RNA species, being most abundant in mRNAs. Studies on enzymes or factors that catalyze, recognize, and remove m 6 A have revealed its comprehensive roles in almost every aspect of mRNA metabolism, as well as in a variety of physiological processes. This review describes the current understanding of the m 6 A modification, particularly the functions of its writers, erasers, readers in RNA metabolism, with an emphasis on its role in regulating the isoform dosage of mRNAs.

Overcoming barriers to public understanding of climate change

NASA Astrophysics Data System (ADS)

Hayhoe, K.

2012-12-01

Humans are interfering with global climate, increasing the risk of serious consequences for human society and the natural environment. As the scientific evidence builds, however, so does the public controversy surrounding this issue. Why is climate change so contentious? What makes it so hard to comprehend? I argue that there is no single reason for this, but rather a perfect storm of multiple confounding factors; scientific, historical, ideological, psychological and even physiological in nature. Education—of both the messengers and the audience—can play a critical role in surmounting many of the common barriers to understanding, accepting, and acting this important issue.

A female sex offender with multiple paraphilias: a psychologic, physiologic (laboratory sexual arousal) and endocrine case study.

PubMed

Cooper, A J; Swaminath, S; Baxter, D; Poulin, C

1990-05-01

A 20 year old female pedophile exhibiting multiple paraphilias and who had been both a victim of incest and an active participant, undertook extensive clinical, psychometric, endocrine and laboratory sexual arousal studies. Her psychiatric, psychometric and physiologic arousal profiles showed similarities to those of a sizable proportion of male child molesters, especially incestors. It is suggested that laboratory arousal tests (using the vaginal photoplethysmograph) may have a role in the assessment of some female sex offenders.

Cognitive behavioral approach to understanding irritable bowel syndrome

PubMed Central

Hauser, Goran; Pletikosic, Sanda; Tkalcic, Mladenka

2014-01-01

Irritable bowel syndrome (IBS) is considered a biopsychosocial disorder, whose onset and precipitation are a consequence of interaction among multiple factors which include motility disturbances, abnormalities of gastrointestinal sensation, gut inflammation and infection, altered processing of afferent sensory information, psychological distress, and affective disturbances. Several models have been proposed in order to describe and explain IBS, each of them focusing on specific aspects or mechanisms of the disorder. This review attempts to present and discuss different determinants of IBS and its symptoms, from a cognitive behavioral therapy framework, distinguishing between the developmental predispositions and precipitants of the disorder, and its perpetuating cognitive, behavioral, affective and physiological factors. The main focus in understanding IBS will be placed on the numerous psychosocial factors, such as personality traits, early experiences, affective disturbances, altered attention and cognitions, avoidance behavior, stress, coping and social support. In conclusion, a symptom perpetuation model is proposed. PMID:24944466

Independence of heritable influences on the food intake of free-living humans.

PubMed

de Castro, John M

2002-01-01

The time of day of meal ingestion, the number of people present at the meal, the subjective state of hunger, and the estimated before-meal contents in the stomach have been established as influences on the amount eaten in a meal and these influences have been shown to be heritable. Because these factors intercorrelate, the calculated heritabilities for some of these variables might result indirectly from their covariation with one of the other heritable variables. The independence of the heritability of the influence of these four factors was investigated with 110 identical and 102 fraternal same-sex and 53 fraternal mixed-sex adult twin pairs who were paid to maintain 7-d food-intake diaries. From the diary reports, the meal sizes were calculated and subjected to multiple regression analysis using the estimated before-meal stomach contents, the reported number of other people present, the subjective hunger ratings, and the time of day of the meal as predictors. Linear structural modeling was applied to the beta-coefficients from the multiple regression to investigate whether the heritability of the influences of these four variables was independent. Significant genetic effects were found for the beta-coefficients for all four variables, indicating that the heritability of their relationship with intake is to some extent independent and heritable. This suggests that influences of multiple factors on intake are influenced by the genes and become part of the total package of genetically determined physiologic, sociocultural, and psychological processes that regulate energy balance.

Heritability of diurnal changes in food intake in free-living humans.

PubMed

de Castro, J M

2001-09-01

The time of day of meal ingestion, the number of people present at the meal, the subjective state of hunger, and the estimated before-meal contents in the stomach have been established as influences on the amount eaten in a meal, and this influence has been shown to be heritable. Because these factors intercorrelate, the possibility that the calculated heritabilities for some of these variables could result indirectly from their convariation with one of the other heritable variables was assessed. The independence of the heritability of the influence of these four factors was investigated with 110 identical and 102 fraternal same-sex and 53 fraternal mixed-sex adult twin pairs who were paid to maintain 7-d food intake diaries. From the diary reports, the meal sizes were calculated and subjected to multiple regression analysis using the estimated before-meal stomach contents, the reported number of other people present, the subjective hunger ratings, and the time of day of the meal as predictors. Linear structural modeling was applied to the beta coefficients from the multiple regression to investigate whether the heritability of the influences of these four variables was independent. Significant genetic effects were found for the beta coefficients for all four variables, indicating that the heritability of their relationship with intake is to some extent heritable. These results suggest that the influences of multiple factors on intake are influenced by the genes and become part of the total package of genetically determined physiologic, sociocultural, and psychological processes that regulate energy balance.

Physiological and biological factors associated with a 24 h treadmill ultra-marathon performance.

PubMed

Millet, G Y; Banfi, J C; Kerherve, H; Morin, J B; Vincent, L; Estrade, C; Geyssant, A; Feasson, L

2011-02-01

The purpose of this study was to examine the physiological and biological factors associated with ultra-endurance performance. Fourteen male runners volunteered to run on a treadmill as many kilometers as possible over a 24-h period (24TR). Maximal oxygen uptake (VO(2max)), velocity associated with VO(2max)(VO(2max)) and running economy (RE) at 8 km/h were measured. A muscle biopsy was also performed in the vastus lateralis muscle. The subjects ran 149.2 ± 15.7 km in 18 h 39 ± 41 min of effective attendance on the treadmill, corresponding to 39.4 ± 4.2% of . Standard multiple-regression analysis showed that performance was significantly (R(2) = 0.82; P = 0.005) related to VO(2max) and specific endurance, i.e. the average speed sustained over the 24TR expressed in . VO(2max) was associated with a high capillary tortuosity (R(2) = 0.66; P = 0.01). Specific endurance was significantly related to RE and citrate synthase activity. It is concluded that a high VO(2max) and an associated developed capillary network are essential for ultra-endurance running performance. The ability to maintain a high %VO(2max) over a 24TR is another factor associated with performance and is mainly related to RE and high mitochondrial oxidative capacity in the vastus lateralis. © 2009 John Wiley & Sons A/S.

Characterizing and Discovering Spatiotemporal Social Contact Patterns for Healthcare.

PubMed

Yang, Bo; Pei, Hongbin; Chen, Hechang; Liu, Jiming; Xia, Shang

2017-08-01

During an epidemic, the spatial, temporal and demographic patterns of disease transmission are determined by multiple factors. In addition to the physiological properties of the pathogens and hosts, the social contact of the host population, which characterizes the reciprocal exposures of individuals to infection according to their demographic structure and various social activities, are also pivotal to understanding and predicting the prevalence of infectious diseases. How social contact is measured will affect the extent to which we can forecast the dynamics of infections in the real world. Most current work focuses on modeling the spatial patterns of static social contact. In this work, we use a novel perspective to address the problem of how to characterize and measure dynamic social contact during an epidemic. We propose an epidemic-model-based tensor deconvolution framework in which the spatiotemporal patterns of social contact are represented by the factors of the tensors. These factors can be discovered using a tensor deconvolution procedure with the integration of epidemic models based on rich types of data, mainly heterogeneous outbreak surveillance data, socio-demographic census data and physiological data from medical reports. Using reproduction models that include SIR/SIS/SEIR/SEIS models as case studies, the efficacy and applications of the proposed framework are theoretically analyzed, empirically validated and demonstrated through a set of rigorous experiments using both synthetic and real-world data.

Outcome and prognostic factors in critically ill patients with systemic lupus erythematosus: a retrospective study.

PubMed

Hsu, Chia-Lin; Chen, Kuan-Yu; Yeh, Pu-Sheng; Hsu, Yeong-Long; Chang, Hou-Tai; Shau, Wen-Yi; Yu, Chia-Li; Yang, Pan-Chyr

2005-06-01

Systemic lupus erythematosus (SLE) is an archetypal autoimmune disease, involving multiple organ systems with varying course and prognosis. However, there is a paucity of clinical data regarding prognostic factors in SLE patients admitted to the intensive care unit (ICU). From January 1992 to December 2000, all patients admitted to the ICU with a diagnosis of SLE were included. Patients were excluded if the diagnosis of SLE was established at or after ICU admission. A multivariate logistic regression model was applied using Acute Physiology and Chronic Health Evaluation II scores and variables that were at least moderately associated (P < 0.2) with survival in the univariate analysis. A total of 51 patients meeting the criteria were included. The mortality rate was 47%. The most common cause of admission was pneumonia with acute respiratory distress syndrome. Multivariate logistic regression analysis showed that intracranial haemorrhage occurring while the patient was in the ICU (relative risk = 18.68), complicating gastrointestinal bleeding (relative risk = 6.97) and concurrent septic shock (relative risk = 77.06) were associated with greater risk of dying, whereas causes of ICU admission and Acute Physiology and Chronic Health Evaluation II score were not significantly associated with death. The mortality rate in critically ill SLE patients was high. Gastrointestinal bleeding, intracranial haemorrhage and septic shock were significant prognostic factors in SLE patients admitted to the ICU.

A multiple disk centrifugal pump as a blood flow device.

PubMed

Miller, G E; Etter, B D; Dorsi, J M

1990-02-01

A multiple disk, shear force, valveless centrifugal pump was studied to determine its suitability as a blood flow device. A pulsatile version of the Tesla viscous flow turbine was designed by modifying the original steady flow pump concept to produce physiological pressures and flows with the aid of controlling circuitry. Pressures and flows from this pump were compared to a Harvard Apparatus pulsatile piston pump. Both pumps were connected to an artificial circulatory system. Frequency and systolic duration were varied over a range of physiological conditions for both pumps. The results indicated that the Tesla pump, operating in a pulsatile mode, is capable of producing physiologic pressures and flows similar to the Harvard pump and other pulsatile blood pumps.

Gait initiation time is associated with the risk of multiple falls-A population-based study.

PubMed

Callisaya, Michele L; Blizzard, Leigh; Martin, Kara; Srikanth, Velandai K

2016-09-01

In a population-based study of older people to examine whether 1) overall gait initiation (GI) time or its components are associated with falls and 2) GI under dual-task is a stronger predictor of falls risk than under single-task. Participants aged 60-85 years were randomly selected from the electoral roll. GI was obtained with a force platform under both single and dual-task conditions. Falls were ascertained prospectively over a 12-month period. Log multinomial regression was used to examine the association between GI time (total and its components) and risk of single and multiple falls. Age, sex and physiological and cognitive falls risk factors were considered as confounders. The mean age of the sample (n=124) was 71.0 (SD 6.8) years and 58.9% (n=73) were male. Over 12 months 21.8% (n=27) of participants reported a single fall and 16.1% (n=20) reported multiple falls. Slower overall GI time under both single (RR all per 100ms 1.28, 95%CI 1.03, 1.58) and dual-task (RR 1.14, 95%CI 1.02, 1.27) was associated with increased risk of multiple, but not single falls (p<0.05). Multiple falls were also associated with slower time to first lateral movement under single-task (RR 1.90 95%CI 0.59, 1.51) and swing time under dual-task condition (RR 1.44 95%CI 1.08, 1.94). Slower GI time is associated with the risk of multiple falls independent of other risk factors, suggesting it could be used as part of a comprehensive falls assessment. Time to the first lateral movement under single-task may be the best measures of this risk. Copyright © 2016 Elsevier B.V. All rights reserved.

Vitamin A is a necessary factor for sympathetic-independent rhythmic activation of mitogen-activated protein kinase in the rat pineal gland.

PubMed

Guillaumond, F; Giraudet, F; Becquet, D; Sage, D; Laforge-Anglade, G; Bosler, O; François-Bellan, A M

2005-02-01

The circadian clock in the suprachiasmatic nucleus (SCN) controls day-to-day physiology and behavior by sending timing messages to multiple peripheral oscillators. In the pineal gland, a major SCN target, circadian events are believed to be driven exclusively by the rhythmic release of norepinephrine from superior cervical ganglia (SCG) neurons relaying clock messages through a polysynaptic pathway. Here we show in rat an SCN-driven daily rhythm of pineal MAPK activation that is not dependent on the SCG and whose maintenance requires vitamin A as a blood-borne factor. This finding challenges the dogma that SCG-released norepinephrine is an exclusive mediator of SCN-pineal communication and allows the assumption that humoral mechanisms are involved in pineal integration of temporal messages.

APP processing and the APP-KPI domain involvement in the amyloid cascade.

PubMed

Menéndez-González, M; Pérez-Pinera, P; Martínez-Rivera, M; Calatayud, M T; Blázquez Menes, B

2005-01-01

Alternative APP mRNA splicing can generate isoforms of APP containing a Kunitz protease inhibitor (KPI) domain. KPI is one of the main serine protease inhibitors. Protein and mRNA KPI(+)APP levels are elevated in Alzheimer's disease (AD) brain and are associated with increased amyloid beta deposition. In the last years increasing evidence on multiple points in the amyloid cascade where KPI(+)APP is involved has been accumulated, admitting an outstanding position in the pathogenesis of AD to the KPI domain. This review focuses on the APP processing, the molecular activity of KPI and its physiological and pathological roles and the KPI involvement in the amyloid cascade through the nerve growth factor, the lipoprotein receptor-related protein, the tumor necrosis factor-alpha converting enzyme and the Notch1 protein.

Simulation of Medical Imaging Systems: Emission and Transmission Tomography

NASA Astrophysics Data System (ADS)

Harrison, Robert L.

Simulation is an important tool in medical imaging research. In patient scans the true underlying anatomy and physiology is unknown. We have no way of knowing in a given scan how various factors are confounding the data: statistical noise; biological variability; patient motion; scattered radiation, dead time, and other data contaminants. Simulation allows us to isolate a single factor of interest, for instance when researchers perform multiple simulations of the same imaging situation to determine the effect of statistical noise or biological variability. Simulations are also increasingly used as a design optimization tool for tomographic scanners. This article gives an overview of the mechanics of emission and transmission tomography simulation, reviews some of the publicly available simulation tools, and discusses trade-offs between the accuracy and efficiency of simulations.

Hormonal regulation of longevity in mammals

PubMed Central

Brown-Borg, Holly M.

2007-01-01

Multiple biological and environmental factors impact the life span of an organism. The endocrine system is a highly integrated physiological system in mammals that regulates metabolism, growth, reproduction, and response to stress, among other functions. As such, this pervasive entity has a major influence on aging and longevity. The growth hormone, insulin-like growth factor-1 and insulin pathways have been at the forefront of hormonal control of aging research in the last few years. Other hormones, including those from the thyroid and reproductive system have also been studied in terms of life span regulation. The relevance of these hormones to human longevity remains to be established, however the evidence from other species including yeast, nematodes, and flies suggest that evolutionarily well-conserved mechanisms are at play and the endocrine system is a key determinant. PMID:17360245

Biotechnological approaches to study plant responses to stress.

PubMed

Pérez-Clemente, Rosa M; Vives, Vicente; Zandalinas, Sara I; López-Climent, María F; Muñoz, Valeria; Gómez-Cadenas, Aurelio

2013-01-01

Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upregulation of the antioxidant machinery, and accumulation of compatible solutes. Over the last few decades advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to abiotic stress conditions. In this paper, recent progresses on systematic analyses of plant responses to stress including genomics, proteomics, metabolomics, and transgenic-based approaches are summarized.

Biotechnological Approaches to Study Plant Responses to Stress

PubMed Central

Pérez-Clemente, Rosa M.; Vives, Vicente; Zandalinas, Sara I.; López-Climent, María F.; Muñoz, Valeria; Gómez-Cadenas, Aurelio

2013-01-01

Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upregulation of the antioxidant machinery, and accumulation of compatible solutes. Over the last few decades advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to abiotic stress conditions. In this paper, recent progresses on systematic analyses of plant responses to stress including genomics, proteomics, metabolomics, and transgenic-based approaches are summarized. PMID:23509757

Platelet-Rich Plasma Derived Growth Factors Contribute to Stem Cell Differentiation in Musculoskeletal Regeneration.

PubMed

Qian, Yun; Han, Qixin; Chen, Wei; Song, Jialin; Zhao, Xiaotian; Ouyang, Yuanming; Yuan, Weien; Fan, Cunyi

2017-01-01

Stem cell treatment and platelet-rich plasma (PRP) therapy are two significant issues in regenerative medicine. Stem cells such as bone marrow mesenchymal stem cells, adipose-derived stem cells and periodontal ligament stem cells can be successfully applied in the field of tissue regeneration. PRP, a natural product isolated from whole blood, can secrete multiple growth factors (GFs) for regulating physiological activities. These GFs can stimulate proliferation and differentiation of different stem cells in injury models. Therefore, combination of both agents receives wide expectations in regenerative medicine, especially in bone, cartilage and tendon repair. In this review, we thoroughly discussed the interaction and underlying mechanisms of PRP derived GFs with stem cells, and assessed their functions in cell differentiation for musculoskeletal regeneration.

Determinants of physiological and perceived physiological stress reactivity in children and adolescents.

PubMed

Evans, Brittany E; Greaves-Lord, Kirstin; Euser, Anja S; Tulen, Joke H M; Franken, Ingmar H A; Huizink, Anja C

2013-01-01

Abnormal physiological stress reactivity is increasingly investigated as a vulnerability marker for various physical and psychological health problems. However, studies are inconsistent in taking into account potential covariates that may influence the developing stress system. We systematically tested determinants (individual, developmental, environmental and substance use-related) of physiological and perceived physiological stress reactivity. We also examined the relation between physiological and perceived physiological stress reactivity. In a stratified sample of 363 children (7-12 years) and 344 adolescents (13-20 years) from the general population, we examined cortisol, heart rate, respiratory sinus arrhythmia and perceived physiological stress reactivity to a psychosocial stress procedure. Using multivariate linear regression models, we found that individual, developmental, environmental and substance use-related factors were related to each of the stress response indices. These determinant factors were different for each of the stress reactivity indices, and different in children versus adolescents. Perceived physiological stress reactivity predicted cortisol reactivity in adolescents only. All other relations between perceived physiological and physiological stress reactivity were not significant. As physiological stress variables are often examined as vulnerability markers for the development of health problems, we maintain that it is essential that future studies take into consideration factors that may account for found relations. Our study provides an overview and indication of which variables should be considered in the investigation of the relation between physiological stress indices and illness.

The Functional Task Test: Results from the One-Year Mission

NASA Technical Reports Server (NTRS)

Bloomberg, J. J; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Laurie, S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.;

Synergistic roles of bone morphogenetic protein 15 and growth differentiation factor 9 in ovarian function.

PubMed

Yan, C; Wang, P; DeMayo, J; DeMayo, F J; Elvin, J A; Carino, C; Prasad, S V; Skinner, S S; Dunbar, B S; Dube, J L; Celeste, A J; Matzuk, M M

2001-06-01

Knockout mouse technology has been used over the last decade to define the essential roles of ovarian-expressed genes and uncover genetic interactions. In particular, we have used this technology to study the function of multiple members of the transforming growth factor-beta superfamily including inhibins, activins, and growth differentiation factor 9 (GDF-9 or Gdf9). Knockout mice lacking GDF-9 are infertile due to a block in folliculogenesis at the primary follicle stage. In addition, recombinant GDF-9 regulates multiple cumulus granulosa cell functions in the periovulatory period including hyaluronic acid synthesis and cumulus expansion. We have also cloned an oocyte-specific homolog of GDF-9 from mice and humans, which is termed bone morphogenetic protein 15 (BMP-15 or Bmp15). To define the function of BMP-15 in mice, we generated embryonic stem cells and knockout mice, which have a null mutation in this X-linked gene. Male chimeric and Bmp15 null mice are normal and fertile. In contrast to Bmp15 null males and Gdf9 knockout females, Bmp15 null females (Bmp15(-/-)) are subfertile and usually have minimal ovarian histopathological defects, but demonstrate decreased ovulation and fertilization rates. To further decipher possible direct or indirect genetic interactions between GDF-9 and BMP-15, we have generated double mutant mice lacking one or both alleles of these related homologs. Double homozygote females (Bmp15(-/-)Gdf9(-/-)) display oocyte loss and cysts and resemble Gdf9(-/-) mutants. In contrast, Bmp15(-/-)Gdf9(+/-) female mice have more severe fertility defects than Bmp15(-/-) females, which appear to be due to abnormalities in ovarian folliculogenesis, cumulus cell physiology, and fertilization. Thus, the dosage of intact Bmp15 and Gdf9 alleles directly influences the destiny of the oocyte during folliculogenesis and in the periovulatory period. These studies have important implications for human fertility control and the maintenance of fertility and normal ovarian physiology.

Overexpression of Tobacco GCN2 Stimulates Multiple Physiological Changes Associated With Stress Tolerance

PubMed Central

Li, Ning; Zhang, Song-jie; Zhao, Qi; Long, Yue; Guo, Hao; Jia, Hong-fang; Yang, Yong-xia; Zhang, Hong-ying; Ye, Xie-feng; Zhang, Song-tao

2018-01-01

General control non-derepressible-2 (GCN2) is a ubiquitous protein kinase that phosphorylates the α subunit of the eukaryotic initiation factor, eIF2, preventing the initiation of a new cycle of protein synthesis, subsequently reducing the global protein biosynthesis. GCN2 can also regulate the response of plants to biotic and abiotic stresses. In this study, two GCN2 homologs, NtGCN2-1 and NtGCN2-2, were cloned from Nicotiana tabacum, and were predicted to have been derived from their progenitors in N. tomentosiformis and N. sylvestris, respectively. The phosphorylation of NteIF2α could be activated by promoting the expression of NtGCN2 with plant hormones, including salicylic acid (SA), azelaic acid (AZA), methyl jasmonate (MeJA), and by imposition of different stresses (Bemisia tabaci infection, drought, and cold), indicating that NtGCN2 is involved in the response of plants to multiple biotic and abiotic stresses. We also observed that the overexpression of NtGCN2-1 significantly influenced different physiological processes. It promoted seed germination and root elongation. The content of total soluble sugars and reducing sugars were decreased, whereas those of chlorophyll a and b were increased in the GCN2 overexpressing plants. In addition, the overexpressing plants had lower content of reactive oxygen species and exhibited higher antioxidant activities. These physiological alterations could be attributed to the changes in the endogenous phytohormones, decrease in the SA and abscisic acid content, and accumulation of MeJA and AZA. It indicated that the overexpression of NtGCN2 in tobacco, stimulated the plant defense responses via phosphorylation of NteIF2α and regulation of plant hormones, and changes in the antioxidant ability and plant nutrient status. PMID:29910821

Rationale and design of a randomized controlled, clinical trial investigating a comprehensive exercise stimulus for improving mobility disability outcomes in persons with multiple sclerosis.

PubMed

Motl, Robert W; Pilutti, Lara A; Sandroff, Brian M; Klaren, Rachel; Balantrapu, Swathi; McAuley, Edward; Sosnoff, Jacob J; Fernhall, Bo

2013-05-01

This randomized controlled trial (RCT) examines the effect of a comprehensive exercise training stimulus on physiological function and mobility disability (i.e., problems walking) in individuals with multiple sclerosis (MS) who have walking impairment. This trial will recruit 30 persons with MS across central Illinois who have an Expanded Disability Status Scale score between 4.0 and 6.0, and those persons will be randomized into either the intervention or control arm of the study; the participants will not be blinded regarding group assignment. The intervention will incorporate equal amounts of aerobic, resistance, and balance modes of training delivered 3 times/week with a gradual progression of duration and intensity across a 6-month period. The control will involve stretching along with minimal muscle strengthening stimuli and will be delivered on the same frequency and duration. The primary outcomes will be clinical, kinematic, patient-rated, and physiological measures of mobility disability. The secondary outcomes will be measures of physiological function including aerobic capacity, muscle strength, and balance. This study will lay the foundation for the design of a subsequent Phase II or Phase III RCT by (a) providing effect sizes that can be included in a power analysis for sample size estimation and (b) investigating whether aerobic capacity, muscle strength, and balance are possible factors associated with the beneficial effect of exercise training on walking outcomes. Taken as a whole, the proposed study and our subsequent research agenda has the potential for advancing the management of mobility disability using exercise training in the 2nd stage of MS. Copyright © 2013 Elsevier Inc. All rights reserved.

Insights in the Fruit Flesh Browning Mechanisms in Solanum melongena Genetic Lines with Opposite Postcut Behavior.

PubMed

Docimo, T; Francese, G; De Palma, M; Mennella, D; Toppino, L; Lo Scalzo, R; Mennella, G; Tucci, M

2016-06-08

Color, taste, flavor, nutritional value, and shelf life are important factors determining quality and healthiness of food and vegetables. These factors are strongly affected by browning processes, occurring after fruit or vegetable cutting. Characterization of ten eggplant genotypes for chlorogenic acid (CGA) content, total phenols (TP), polyphenoloxidase (PPO) activity, and browning tendency corroborated a lack of significant correlations between biochemical factors and fruit flesh browning. Further in-depth molecular and biochemical analyses of two divergent eggplant genetic lines, AM199 (high browning) and AM086 (low browning), within 30 min from cutting, highlighted differences in the physiological mechanisms underlying the browning process. qRT-PCR analysis revealed distinct activation mechanisms of CGA biosynthetic and PPO genes in the two genetic lines. Metabolic data on CGA, sugars, and ascorbic acid contents confirmed that their different browning tendency matched with different metabolic responses to cutting. Our findings suggest that the complex mechanism of flesh browning in the two eggplant genetic lines might be mediated by multiple specific factors.

Is shade beneficial for mediterranean shrubs experiencing periods of extreme drought and late-winter frosts?

PubMed

Valladares, Fernando; Zaragoza-Castells, Joana; Sánchez-Gómez, David; Matesanz, Silvia; Alonso, Beatriz; Portsmuth, Angelika; Delgado, Antonio; Atkin, Owen K

2008-12-01

Plants are naturally exposed to multiple, frequently interactive stress factors, most of which are becoming more severe due to global change. Established plants have been reported to facilitate the establishment of juvenile plants, but net effects of plant-plant interactions are difficult to assess due to complex interactions among environmental factors. An investigation was carried out in order to determine how two dominant evergreen shrubs (Quercus ilex and Arctostaphylos uva-ursi) co-occurring in continental, Mediterranean habitats respond to multiple abiotic stresses and whether the shaded understorey conditions ameliorate the negative effects of drought and winter frosts on the physiology of leaves. Microclimate and ecophysiology of sun and shade plants were studied at a continental plateau in central Spain during 2004-2005, with 2005 being one of the driest and hottest years on record; several late-winter frosts also occurred in 2005. Daytime air temperature and vapour pressure deficit were lower in the shade than in the sun, but soil moisture was also lower in the shade during the spring and summer of 2005, and night-time temperatures were higher in the shade. Water potential, photochemical efficiency, light-saturated photosynthesis, stomatal conductance and leaf 13C composition differed between sun and shade individuals throughout the seasons, but differences were species specific. Shade was beneficial for leaf-level physiology in Q. ilex during winter, detrimental during spring for both species, and of little consequence in summer. The results suggest that beneficial effects of shade can be eclipsed by reduced soil moisture during dry years, which are expected to be more frequent in the most likely climate change scenarios for the Mediterranean region.

Is Shade Beneficial for Mediterranean Shrubs Experiencing Periods of Extreme Drought and Late-winter Frosts?

PubMed Central

Valladares, Fernando; Zaragoza-Castells, Joana; Sánchez-Gómez, David; Matesanz, Silvia; Alonso, Beatriz; Portsmuth, Angelika; Delgado, Antonio; Atkin, Owen K.

2008-01-01

Background and Aims Plants are naturally exposed to multiple, frequently interactive stress factors, most of which are becoming more severe due to global change. Established plants have been reported to facilitate the establishment of juvenile plants, but net effects of plant–plant interactions are difficult to assess due to complex interactions among environmental factors. An investigation was carried out in order to determine how two dominant evergreen shrubs (Quercus ilex and Arctostaphylos uva-ursi) co-occurring in continental, Mediterranean habitats respond to multiple abiotic stresses and whether the shaded understorey conditions ameliorate the negative effects of drought and winter frosts on the physiology of leaves. Methods Microclimate and ecophysiology of sun and shade plants were studied at a continental plateau in central Spain during 2004–2005, with 2005 being one of the driest and hottest years on record; several late-winter frosts also occurred in 2005. Key Results Daytime air temperature and vapour pressure deficit were lower in the shade than in the sun, but soil moisture was also lower in the shade during the spring and summer of 2005, and night-time temperatures were higher in the shade. Water potential, photochemical efficiency, light-saturated photosynthesis, stomatal conductance and leaf 13C composition differed between sun and shade individuals throughout the seasons, but differences were species specific. Shade was beneficial for leaf-level physiology in Q. ilex during winter, detrimental during spring for both species, and of little consequence in summer. Conclusions The results suggest that beneficial effects of shade can be eclipsed by reduced soil moisture during dry years, which are expected to be more frequent in the most likely climate change scenarios for the Mediterranean region. PMID:18819947

Protein Cofactors Are Essential for High-Affinity DNA Binding by the Nuclear Factor κB RelA Subunit.

PubMed

Mulero, Maria Carmen; Shahabi, Shandy; Ko, Myung Soo; Schiffer, Jamie M; Huang, De-Bin; Wang, Vivien Ya-Fan; Amaro, Rommie E; Huxford, Tom; Ghosh, Gourisankar

2018-05-22

Transcription activator proteins typically contain two functional domains: a DNA binding domain (DBD) that binds to DNA with sequence specificity and an activation domain (AD) whose established function is to recruit RNA polymerase. In this report, we show that purified recombinant nuclear factor κB (NF-κB) RelA dimers bind specific κB DNA sites with an affinity significantly lower than that of the same dimers from nuclear extracts of activated cells, suggesting that additional nuclear cofactors might facilitate DNA binding by the RelA dimers. Additionally, recombinant RelA binds DNA with relatively low affinity at a physiological salt concentration in vitro. The addition of p53 or RPS3 (ribosomal protein S3) increases RelA:DNA binding affinity 2- to >50-fold depending on the protein and ionic conditions. These cofactor proteins do not form stable ternary complexes, suggesting that they stabilize the RelA:DNA complex through dynamic interactions. Surprisingly, the RelA-DBD alone fails to bind DNA under the same solution conditions even in the presence of cofactors, suggesting an important role of the RelA-AD in DNA binding. Reduced RelA:DNA binding at a physiological ionic strength suggests that multiple cofactors might be acting simultaneously to mitigate the electrolyte effect and stabilize the RelA:DNA complex in vivo. Overall, our observations suggest that the RelA-AD and multiple cofactor proteins function cooperatively to prime the RelA-DBD and stabilize the RelA:DNA complex in cells. Our study provides a mechanism for nuclear cofactor proteins in NF-κB-dependent gene regulation.

Fibroblast growth factors in cardiovascular disease: The emerging role of FGF21.

PubMed

Domouzoglou, Eleni M; Naka, Katerina K; Vlahos, Antonios P; Papafaklis, Michail I; Michalis, Lampros K; Tsatsoulis, Agathoklis; Maratos-Flier, Eleftheria

2015-09-15

Early detection of risk factors for enhanced primary prevention and novel therapies for treating the chronic consequences of cardiovascular disease are of the utmost importance for reducing morbidity. Recently, fibroblast growth factors (FGFs) have been intensively studied as potential new molecules in the prevention and treatment of cardiovascular disease mainly attributable to metabolic effects and angiogenic actions. Members of the endocrine FGF family have been shown to increase metabolic rate, decrease adiposity, and restore glucose homeostasis, suggesting a multiple metabolic role. Serum levels of FGFs have been associated with established cardiovascular risk factors as well as with the severity and extent of coronary artery disease and could be useful for prediction of cardiovascular death. Furthermore, preclinical investigations and clinical trials have tested FGF administration for therapeutic angiogenesis in ischemic vascular disease, demonstrating a potential role in improving angina and limb function. FGF21 has lately emerged as a potent metabolic regulator with multiple effects that ultimately improve the lipoprotein profile. Early studies show that FGF21 is associated with the presence of atherosclerosis and may play a protective role against plaque formation by improving endothelial function. The present review highlights recent investigations suggesting that FGFs, in particular FGF21, may be useful as markers of cardiovascular risk and may also serve as protective/therapeutic agents in cardiovascular disease. Copyright © 2015 the American Physiological Society.

Physiological and functional failure in chronic obstructive pulmonary disease, congestive heart failure and cancer: a debilitating intersection of sarcopenia, cachexia and breathlessness.

PubMed

Dudgeon, Deborah; Baracos, Vickie E

2016-09-01

Loss of skeletal muscle mass and cachexia are important manifestations of chronic obstructive pulmonary disease and have been associated with breathlessness, functional limitation and poor prognosis. A number of other life-limiting illnesses, including cancer and chronic heart failure as well as acute conditions seen in ICU such as sepsis, are characteristically associated with cachexia and sarcopenia. These conditions may have respiratory muscle atrophy of sufficient magnitude to contribute to the development of breathlessness and associated functional limitation. The purpose of this review is to summarize findings related to a direct role for severe respiratory muscle wasting in the etiology of breathlessness in advanced, life limiting illness. Localized wasting of respiratory muscles appears to be part of systemic wasting of skeletal muscles, driven by deconditioning, nutritional insufficiencies and inflammation, and because of disease-specific factors (tumor factors and exacerbations), anabolic insufficiency, autonomic dysfunction, drugs (such as corticosteroids and chemotherapy agents), mechanical ventilation and comorbidities. Marked morphological and biochemical abnormalities have been noted in diaphragm muscle biopsies. Older patients with multiple comorbidities associated with muscle loss and cachexia are likely to be at elevated risk of respiratory muscle atrophy and functional loss, because of the presence of multiple, interacting etiologic factors.

Single-molecule manipulation reveals supercoiling-dependent modulation of lac repressor-mediated DNA looping

PubMed Central

Normanno, Davide; Vanzi, Francesco; Pavone, Francesco Saverio

2008-01-01

Gene expression regulation is a fundamental biological process which deploys specific sets of genomic information depending on physiological or environmental conditions. Several transcription factors (including lac repressor, LacI) are present in the cell at very low copy number and increase their local concentration by binding to multiple sites on DNA and looping the intervening sequence. In this work, we employ single-molecule manipulation to experimentally address the role of DNA supercoiling in the dynamics and stability of LacI-mediated DNA looping. We performed measurements over a range of degrees of supercoiling between −0.026 and +0.026, in the absence of axial stretching forces. A supercoiling-dependent modulation of the lifetimes of both the looped and unlooped states was observed. Our experiments also provide evidence for multiple structural conformations of the LacI–DNA complex, depending on torsional constraints. The supercoiling-dependent modulation demonstrated here adds an important element to the model of the lac operon. In fact, the complex network of proteins acting on the DNA in a living cell constantly modifies its topological and mechanical properties: our observations demonstrate the possibility of establishing a signaling pathway from factors affecting DNA supercoiling to transcription factors responsible for the regulation of specific sets of genes. PMID:18310101

Profibrotic TGFβ responses require the cooperative action of PDGF and ErbB receptor tyrosine kinases.

PubMed

Andrianifahanana, Mahefatiana; Wilkes, Mark C; Gupta, Shiv K; Rahimi, Rod A; Repellin, Claire E; Edens, Maryanne; Wittenberger, Joshua; Yin, Xueqian; Maidl, Elizabeth; Becker, Jackson; Leof, Edward B

2013-11-01

Transforming growth factor β (TGFβ) has significant profibrotic activity both in vitro and in vivo. This reflects its capacity to stimulate fibrogenic mediators and induce the expression of other profibrotic cytokines such as platelet-derived growth factor (PDGF) and epidermal growth factor (EGF/ErbB) ligands. Here we address both the mechanisms by which TGFβ induced ErbB ligands and the physiological significance of inhibiting multiple TGFβ-regulated processes. The data document that ErbB ligand induction requires PDGF receptor (PDGFR) mediation and engages a positive autocrine/paracrine feedback loop via ErbB receptors. Whereas PDGFRs are essential for TGFβ-stimulated ErbB ligand up-regulation, TGFβ-specific signals are also required for ErbB receptor activation. Subsequent profibrotic responses are shown to involve the cooperative action of PDGF and ErbB signaling. Moreover, using a murine treatment model of bleomycin-induced pulmonary fibrosis we found that inhibition of TGFβ/PDGF and ErbB pathways with imatinib plus lapatinib, respectively, not only prevented myofibroblast gene expression to a greater extent than either drug alone, but also essentially stabilized gas exchange (oxygen saturation) as an overall measure of lung function. These observations provide important mechanistic insights into profibrotic TGFβ signaling and indicate that targeting multiple cytokines represents a possible strategy to ameliorate organ fibrosis dependent on TGFβ.

Cardiovascular Disease Prevalence and Risk Factors of Persons with Mental Retardation

ERIC Educational Resources Information Center

Draheim, Christopher C.

2006-01-01

This paper reviews the recent literature on cardiovascular disease (CVD) prevalence, CVD-related mortality, physiological CVD risk factors, and behavioral CVD risk factors in adults with mental retardation (MR). The literature on the potential influences of modifiable behavioral CVD risk factors and the physiological CVD risk factors are also…

Microglia promote learning-dependent synapse formation through BDNF

PubMed Central

Parkhurst, Christopher N.; Yang, Guang; Ninan, Ipe; Savas, Jeffrey N.; Yates, John R.; Lafaille, Juan J.; Hempstead, Barbara L.; Littman, Dan R.; Gan, Wen-Biao

2014-01-01

SUMMARY Microglia are the resident macrophages of the central nervous system and their functions have been extensively studied in various brain pathologies. The physiological roles of microglia in brain plasticity and function, however, remain unclear. To address this question, we generated CX3CR1CreER mice expressing tamoxifen-inducible Cre recombinase that allow for specific manipulation of gene function in microglia. Using CX3CR1CreER to drive diphtheria toxin receptor expression in microglia, we found that microglia could be specifically depleted from the brain upon diphtheria toxin administration. Mice depleted of microglia show deficits in multiple learning tasks and a significant reduction in motor learning-dependent synapse formation. Furthermore, Cre-dependent removal of brain-derived neurotrophic factor (BDNF) from microglia largely recapitulated the effects of microglia depletion. Microglial BDNF increases neuronal TrkB phosphorylation, a key mediator of synaptic plasticity. Together, our findings reveal important physiological functions of microglia in learning and memory by promoting learning-related synapse formation through BDNF signaling. PMID:24360280

Hyperhomocysteinemia and neurologic disorders: a review.

PubMed

Ansari, Ramin; Mahta, Ali; Mallack, Eric; Luo, Jin Jun

2014-10-01

Homocysteine (Hcy) is a sulfur-containing amino acid that is generated during methionine metabolism. It has a physiologic role in DNA metabolism via methylation, a process governed by the presentation of folate, and vitamins B6 and B12. Physiologic Hcy levels are determined primarily by dietary intake and vitamin status. Elevated plasma levels of Hcy (eHcy) can be caused by deficiency of either vitamin B12 or folate, or a combination thereof. Certain genetic factors also cause eHcy, such as C667T substitution of the gene encoding methylenetetrahydrofolate reductase. eHcy has been observed in several medical conditions, such as cardiovascular disorders, atherosclerosis, myocardial infarction, stroke, minimal cognitive impairment, dementia, Parkinson's disease, multiple sclerosis, epilepsy, and eclampsia. There is evidence from laboratory and clinical studies that Hcy, and especially eHcy, exerts direct toxic effects on both the vascular and nervous systems. This article provides a review of the current literature on the possible roles of eHcy relevant to various neurologic disorders.

Hyperhomocysteinemia and Neurologic Disorders: a Review

PubMed Central

Ansari, Ramin; Mallack, Eric; Luo, Jin Jun

2014-01-01

Homocysteine (Hcy) is a sulfur-containing amino acid that is generated during methionine metabolism. It has a physiologic role in DNA metabolism via methylation, a process governed by the presentation of folate, and vitamins B6 and B12. Physiologic Hcy levels are determined primarily by dietary intake and vitamin status. Elevated plasma levels of Hcy (eHcy) can be caused by deficiency of either vitamin B12 or folate, or a combination thereof. Certain genetic factors also cause eHcy, such as C667T substitution of the gene encoding methylenetetrahydrofolate reductase. eHcy has been observed in several medical conditions, such as cardiovascular disorders, atherosclerosis, myocardial infarction, stroke, minimal cognitive impairment, dementia, Parkinson's disease, multiple sclerosis, epilepsy, and eclampsia. There is evidence from laboratory and clinical studies that Hcy, and especially eHcy, exerts direct toxic effects on both the vascular and nervous systems. This article provides a review of the current literature on the possible roles of eHcy relevant to various neurologic disorders. PMID:25324876

Modifications of pancreatic diffusion MRI by tissue characteristics: what are we weighting for?

PubMed

Nissan, Noam

2017-08-01

Diffusion-weighted imaging holds the potential to improve the diagnosis and biological characterization of pancreatic disease, and in particular pancreatic cancer, which exhibits decreased values of the apparent diffusion coefficient (ADC). Yet, variable and overlapping ADC values have been reported for the healthy and the pathological pancreas, including for cancer and other benign conditions. This controversy reflects the complexity of probing the water-diffusion process in the pancreas, which is dependent upon multiple biological factors within this organ's unique physiological environment. In recent years, extensive studies have investigated the correlation between tissue properties including cellularity, vascularity, fibrosis, secretion and microstructure and pancreatic diffusivity. Understanding how the various physiological and pathological features and the underlying functional processes affect the diffusion measurement may serve to optimize the method for improved diagnostic gain. Therefore, the aim of the present review article is to elucidate the relationship between pancreatic tissue characteristics and diffusion MRI measurement. Copyright © 2017 John Wiley & Sons, Ltd.

Lysophosphatidic acid as a lipid mediator with multiple biological actions.

PubMed

Aikawa, Shizu; Hashimoto, Takafumi; Kano, Kuniyuki; Aoki, Junken

2015-02-01

Lysophosphatidic acid (LPA) is one of the simplest glycerophospholipids with one fatty acid chain and a phosphate group as a polar head. Although LPA had been viewed just as a metabolic intermediate in de novo lipid synthetic pathways, it has recently been paid much attention as a lipid mediator. LPA exerts many kinds of cellular processes, such as cell proliferation and smooth muscle contraction, through cognate G protein-coupled receptors. Because lipids are not coded by the genome directly, it is difficult to know their patho- and physiological roles. However, recent studies have identified several key factors mediating the biological roles of LPA, such as receptors and producing enzymes. In addition, studies of transgenic and gene knockout animals for these LPA-related genes, have revealed the biological significance of LPA. In this review we will summarize recent advances in the studies of LPA production and its roles in both physiological and pathological conditions. © The Authors 2014. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Redox-regulated growth factor survival signaling.

PubMed

Woolley, John F; Corcoran, Aoife; Groeger, Gillian; Landry, William D; Cotter, Thomas G

2013-11-20

Once the thought of as unwanted byproducts of cellular respiration in eukaryotes, reactive oxygen species (ROS) have been shown to facilitate essential physiological roles. It is now understood that ROS are critical mediators of intracellular signaling. Control of signal transduction downstream of growth factor receptors by ROS is a complex process whose details are only recently coming to light. Indeed, recent evidence points to control of signal propagation by ROS at multiple levels in the typical cascade. Growth factor stimulation activates nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Noxs) at the membrane, producing superoxide in the extracellular matrix, which is catalyzed to the membrane-permeable hydrogen peroxide (H2O2) that mediates intracellular signaling events. The potential for H2O2, however, to disrupt cellular functions by damaging proteins and nucleic acids demands that its levels are kept in check by receptor-associated peroxiredoxins. This interplay of Nox and peroxiredoxin activity moderates levels of H2O2 sufficiently to modify signaling partners locally. Among the best studied of these partners are redox-controlled phosphatases that are inactivated by H2O2. Phosphatases regulate signal propagation downstream of receptors, and thus their inactivation allows a further level of control. Transmission of information further downstream to targets such as transcription factors, themselves regulated by ROS, completes this pathway. Thus, signal propagation or attenuation can be dictated by ROS at multiple points. Given the complex nature of these processes, we envisage the emerging trends in the field of redox signaling in the context of growth factor stimulation.

Determinants of Physiological and Perceived Physiological Stress Reactivity in Children and Adolescents

PubMed Central

Evans, Brittany E.; Greaves-Lord, Kirstin; Euser, Anja S.; Tulen, Joke H. M.; Franken, Ingmar H. A.; Huizink, Anja C.

2013-01-01

Aims Abnormal physiological stress reactivity is increasingly investigated as a vulnerability marker for various physical and psychological health problems. However, studies are inconsistent in taking into account potential covariates that may influence the developing stress system. We systematically tested determinants (individual, developmental, environmental and substance use-related) of physiological and perceived physiological stress reactivity. We also examined the relation between physiological and perceived physiological stress reactivity. Method In a stratified sample of 363 children (7–12 years) and 344 adolescents (13–20 years) from the general population, we examined cortisol, heart rate, respiratory sinus arrhythmia and perceived physiological stress reactivity to a psychosocial stress procedure. Results Using multivariate linear regression models, we found that individual, developmental, environmental and substance use-related factors were related to each of the stress response indices. These determinant factors were different for each of the stress reactivity indices, and different in children versus adolescents. Perceived physiological stress reactivity predicted cortisol reactivity in adolescents only. All other relations between perceived physiological and physiological stress reactivity were not significant. Conclusions As physiological stress variables are often examined as vulnerability markers for the development of health problems, we maintain that it is essential that future studies take into consideration factors that may account for found relations. Our study provides an overview and indication of which variables should be considered in the investigation of the relation between physiological stress indices and illness. PMID:23620785

Kinetic therapy in multiple trauma patients with severe blunt chest trauma: an analysis at a level-1 trauma center.

PubMed

Zeckey, C; Wendt, K; Mommsen, P; Winkelmann, M; Frömke, C; Weidemann, J; Stübig, T; Krettek, C; Hildebrand, F

2015-01-01

Chest trauma is a relevant risk factor for mortality after multiple trauma. Kinetic therapy (KT) represents a potential treatment option in order to restore pulmonary function. Decision criteria for performing kinetic therapy are not fully elucidated. The purpose of this study was to investigate the decision making process to initiate kinetic therapy in a well defined multiple trauma cohort. A retrospective analysis (2000-2009) of polytrauma patients (age > 16 years, ISS ⩾ 16) with severe chest trauma (AIS(Chest) ⩾ 3) was performed. Patients with AIS(Head) ⩾ 3 were excluded. Patients receiving either kinetic (KT+) or lung protective ventilation strategy (KT-) were compared. Chest trauma was classified according to the AIS(Chest), Pulmonary Contusion Score (PCS), Wagner Jamieson Score and Thoracic Trauma Severity Score (TTS). There were multiple outcome parameters investigated included mortality, posttraumatic complications and clinical data. A multivariate regression analysis was performed. Two hundred and eighty-three patients were included (KT+: n=160; KT-: n=123). AIS(Chest), age and gender were comparable in both groups. There were significant higher values of the ISS, PCS, Wagner Jamieson Score and TTS in group KT+. The incidence of posttraumatic complications and mortality was increased compared to group KT- (p< 0.05). Despite that, kinetic therapy failed to be an independent risk factor for mortality in multivariate logistic regression analysis. Kinetic therapy is an option in severely injured patients with severe chest trauma. Decision making is not only based on anatomical aspects such as the AIS(Chest), but on overall injury severity, pulmonary contusions and physiological deterioration. It could be assumed that the increased mortality in patients receiving KT is primarily caused by these factors and does not reflect an independent adverse effect of KT. Furthermore, KT was not shown to be an independent risk factor for mortality.

SHP2 sails from physiology to pathology.

PubMed

Tajan, Mylène; de Rocca Serra, Audrey; Valet, Philippe; Edouard, Thomas; Yart, Armelle

2015-10-01

Over the two past decades, mutations of the PTPN11 gene, encoding the ubiquitous protein tyrosine phosphatase SHP2 (SH2 domain-containing tyrosine phosphatase 2), have been identified as the causal factor of several developmental diseases (Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NS-ML), and metachondromatosis), and malignancies (juvenile myelomonocytic leukemia). SHP2 plays essential physiological functions in organism development and homeostasis maintenance by regulating fundamental intracellular signaling pathways in response to a wide range of growth factors and hormones, notably the pleiotropic Ras/Mitogen-Activated Protein Kinase (MAPK) and the Phosphoinositide-3 Kinase (PI3K)/AKT cascades. Analysis of the biochemical impacts of PTPN11 mutations first identified both loss-of-function and gain-of-function mutations, as well as more subtle defects, highlighting the major pathophysiological consequences of SHP2 dysregulation. Then, functional genetic studies provided insights into the molecular dysregulations that link SHP2 mutants to the development of specific traits of the diseases, paving the way for the design of specific therapies for affected patients. In this review, we first provide an overview of SHP2's structure and regulation, then describe its molecular roles, notably its functions in modulating the Ras/MAPK and PI3K/AKT signaling pathways, and its physiological roles in organism development and homeostasis. In the second part, we describe the different PTPN11 mutation-associated pathologies and their clinical manifestations, with particular focus on the biochemical and signaling outcomes of NS and NS-ML-associated mutations, and on the recent advances regarding the pathophysiology of these diseases. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Exercise Hypertension.

PubMed

Schultz, Martin G; Sharman, James E

2014-05-01

Irrespective of apparent 'normal' resting blood pressure (BP), some individuals may experience an excessive elevation in BP with exercise (i.e. systolic BP ≥210 mm Hg in men or ≥190 mm Hg in women or diastolic BP ≥110 mm Hg in men or women), a condition termed exercise hypertension or a 'hypertensive response to exercise' (HRE). An HRE is a relatively common condition that is identified during standard exercise stress testing; however, due to a lack of information with respect to the clinical ramifications of an HRE, little value is usually placed on such a finding. In this review, we discuss both the clinical importance and underlying physiological contributors of exercise hypertension. Indeed, an HRE is associated with an increased propensity for target organ damage and also predicts the future development of hypertension, cardiovascular events and mortality, independent of resting BP. Moreover, recent work has highlighted that some of the elevated cardiovascular risks associated with an HRE may be related to high-normal resting BP (pre-hypertension) or ambulatory 'masked' hypertension and that an HRE may be an early warning signal of abnormal BP control that is otherwise undetected with clinic BP. Whilst an HRE may be amenable to treatment via pharmacological and lifestyle interventions, the exact physiological mechanism of an HRE remains elusive, but it is likely a manifestation of multiple factors including large artery stiffness, increased peripheral resistance, neural circulatory control and metabolic irregularity. Future research focus may be directed towards determining threshold values to denote the increased risk associated with an HRE and further resolution of the underlying physiological factors involved in the pathogenesis of an HRE.

Interpreting the Possible Ecological Role(s) of Cyanotoxins: Compounds for Competitive Advantage and/or Physiological Aide?

PubMed Central

Holland, Aleicia; Kinnear, Susan

2013-01-01

To date, most research on freshwater cyanotoxin(s) has focused on understanding the dynamics of toxin production and decomposition, as well as evaluating the environmental conditions that trigger toxin production, all with the objective of informing management strategies and options for risk reduction. Comparatively few research studies have considered how this information can be used to understand the broader ecological role of cyanotoxin(s), and the possible applications of this knowledge to the management of toxic blooms. This paper explores the ecological, toxicological, and genetic evidence for cyanotoxin production in natural environments. The possible evolutionary advantages of toxin production are grouped into two main themes: That of “competitive advantage” or “physiological aide”. The first grouping illustrates how compounds produced by cyanobacteria may have originated from the need for a cellular defence mechanism, in response to grazing pressure and/or resource competition. The second grouping considers the contribution that secondary metabolites make to improved cellular physiology, through benefits to homeostasis, photosynthetic efficiencies, and accelerated growth rates. The discussion also includes other factors in the debate about possible evolutionary roles for toxins, such as different modes of exposures and effects on non-target (i.e., non-competitive) species. The paper demonstrates that complex and multiple factors are at play in driving evolutionary processes in aquatic environments. This information may provide a fresh perspective on managing toxic blooms, including the need to use a “systems approach” to understand how physico-chemical conditions, as well biological stressors, interact to trigger toxin production. PMID:23807545

Interpreting the possible ecological role(s) of cyanotoxins: compounds for competitive advantage and/or physiological aide?

PubMed

Holland, Aleicia; Kinnear, Susan

2013-06-27

To date, most research on freshwater cyanotoxin(s) has focused on understanding the dynamics of toxin production and decomposition, as well as evaluating the environmental conditions that trigger toxin production, all with the objective of informing management strategies and options for risk reduction. Comparatively few research studies have considered how this information can be used to understand the broader ecological role of cyanotoxin(s), and the possible applications of this knowledge to the management of toxic blooms. This paper explores the ecological, toxicological, and genetic evidence for cyanotoxin production in natural environments. The possible evolutionary advantages of toxin production are grouped into two main themes: That of "competitive advantage" or "physiological aide". The first grouping illustrates how compounds produced by cyanobacteria may have originated from the need for a cellular defence mechanism, in response to grazing pressure and/or resource competition. The second grouping considers the contribution that secondary metabolites make to improved cellular physiology, through benefits to homeostasis, photosynthetic efficiencies, and accelerated growth rates. The discussion also includes other factors in the debate about possible evolutionary roles for toxins, such as different modes of exposures and effects on non-target (i.e., non-competitive) species. The paper demonstrates that complex and multiple factors are at play in driving evolutionary processes in aquatic environments. This information may provide a fresh perspective on managing toxic blooms, including the need to use a "systems approach" to understand how physico-chemical conditions, as well biological stressors, interact to trigger toxin production.

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.

Structure-function relations in physiology education: Where's the mechanism?

PubMed

Lira, Matthew E; Gardner, Stephanie M

2017-06-01

Physiology demands systems thinking: reasoning within and between levels of biological organization and across different organ systems. Many physiological mechanisms explain how structures and their properties interact at one level of organization to produce emergent functions at a higher level of organization. Current physiology principles, such as structure-function relations, selectively neglect mechanisms by not mentioning this term explicitly. We explored how students characterized mechanisms and functions to shed light on how students make sense of these terms. Students characterized mechanisms as 1 ) processes that occur at levels of organization lower than that of functions; and 2 ) as detailed events with many steps involved. We also found that students produced more variability in how they characterized functions compared with mechanisms: students characterized functions in relation to multiple levels of organization and multiple definitions. We interpret these results as evidence that students see mechanisms as holding a more narrow definition than used in the biological sciences, and that students struggle to coordinate and distinguish mechanisms from functions due to cognitive processes germane to learning in many domains. We offer the instructional suggestion that we scaffold student learning by affording students opportunities to relate and also distinguish between these terms so central to understanding physiology. Copyright © 2017 the American Physiological Society.

Monitoring of physiological parameters from multiple patients using wireless sensor network.

PubMed

Yuce, Mehmet R; Ng, Peng Choong; Khan, Jamil Y

2008-10-01

This paper presents a wireless sensor network system that has the capability to monitor physiological parameters from multiple patient bodies. The system uses the Medical Implant Communication Service band between the sensor nodes and a remote central control unit (CCU) that behaves as a base station. The CCU communicates with another network standard (the internet or a mobile network) for a long distance data transfer. The proposed system offers mobility to patients and flexibility to medical staff to obtain patient's physiological data on demand basis via Internet. A prototype sensor network including hardware, firmware and software designs has been implemented and tested. The developed system has been optimized for power consumption by having the nodes sleep when there is no communication via a bidirectional communication.

Common Student Misconceptions in Exercise Physiology and Biochemistry

ERIC Educational Resources Information Center

Morton, James P.; Doran, Dominic A.; MacLaren, Don P. M.

2008-01-01

The present study represents a preliminary investigation designed to identify common misconceptions in students' understanding of physiological and biochemical topics within the academic domain of sport and exercise sciences. A specifically designed misconception inventory (consisting of 10 multiple-choice questions) was administered to a cohort…

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.

SMAD Signaling Is Required for Structural Integrity of the Female Reproductive Tract and Uterine Function During Early Pregnancy in Mice1

PubMed Central

Rodriguez, Amanda; Tripurani, Swamy K.; Burton, Jason C.; Clementi, Caterina; Larina, Irina; Pangas, Stephanie A.

2016-01-01

Pregnancy is a complex physiological process tightly controlled by the interplay among hormones, morphogens, transcription factors, and signaling pathways. Although recent studies using genetically engineered mouse models have revealed that ligands and receptors of transforming growth factor beta (TGFbeta) and bone morphogenetic protein (BMP) signaling pathways are essential for multiple reproductive events during pregnancy, the functional role of SMAD transcription factors, which serve as the canonical signaling platform for the TGFbeta/BMP pathways, in the oviduct and uterus is undefined. Here, we used a mouse model containing triple conditional deletion of the BMP receptor signaling Smads (Smad1 and Smad5) and Smad4, the central mediator of both TGFbeta and BMP signaling, to investigate the role of the SMADs in reproductive tract structure and function in cells from the Amhr2 lineage. Unlike the respective single- or double-knockouts, female Smad1flox/flox Smad5flox/flox Smad4flox/flox Amhr2cre/+conditional knockout (i.e., Smad1/5/4-Amhr2-cre KO) mice are sterile. We discovered that Smad1/5/4-Amhr2-cre KO females have malformed oviducts that subsequently develop oviductal diverticuli. These oviducts showed dysregulation of multiple genes essential for oviduct and smooth muscle development. In addition, uteri from Smad1/5/4-Amhr2-cre KO females exhibit multiple defects in stroma, epithelium, and smooth muscle layers and fail to assemble a closed uterine lumen upon embryo implantation, with defective uterine decidualization that led to pregnancy loss at early to mid-gestation. Taken together, our study uncovers a new role for the SMAD transcription factors in maintaining the structural and functional integrity of oviduct and uterus, required for establishment and maintenance of pregnancy. PMID:27335065

[Natural factors influencing sleep].

PubMed

Jurkowski, Marek K; Bobek-Billewicz, Barbara

2007-01-01

Sleep is a universal phenomenon of human and animal lives, although the importance of sleep for homeo-stasis is still unknown. Sleep disturbances influence many behavioral and physiologic processes, leading to health complications including death. On the other hand, sleep improvement can beneficially influence the course of healing of many disorders and can be a prognostic of health recovery. The factors influencing sleep have different biological and chemical origins. They are classical hormones, hypothalamic releasing and inhibitory hormones, neuropeptides, peptides and others as cytokines, prostaglandins, oleamid, adenosine, nitric oxide. These factors regulate most physiologic processes and are likely elements integrating sleep with physiology and physiology with sleep in health and disorders.

Redefining the gut as the motor of critical illness

PubMed Central

Mittal, Rohit; Coopersmith, Craig M.

2013-01-01

The gut is hypothesized to play a central role in the progression of sepsis and multiple organ dysfunction syndrome. Critical illness alters gut integrity by increasing epithelial apoptosis and permeability and by decreasing epithelial proliferation and mucus integrity. Additionally, toxic gut-derived lymph induces distant organ injury. Although the endogenous microflora ordinarily exist in a symbiotic relationship with the gut epithelium, severe physiologic insults alter this relationship, leading to induction of virulence factors in the microbiome, which, in turn, can perpetuate or worsen critical illness. This review highlights newly discovered ways in which the gut acts as the motor that perpetuates the systemic inflammatory response in critical illness. PMID:24055446

Endocrinology of anorexia nervosa in young people: recent insights

PubMed Central

Singhal, Vibha; Misra, Madhusmita; Klibanski, Anne

2014-01-01

Purpose of review Anorexia nervosa is among the most prevalent chronic medical conditions in young adults. It has acute as well as long-term consequences, some of which, such as low bone mineral density (BMD), are not completely reversible even after weight restoration. This review discusses our current understanding of endocrine consequences of anorexia nervosa. Recent findings Anorexia nervosa is characterized by changes in multiple neuroendocrine axes including acquired hypogonadotropic hypogonadism, growth hormone resistance with low insulin-like growth factor-1 (likely mediated by fibroblast growth factor-1), relative hypercortisolemia, alterations in adipokines such as leptin, adiponectin and resistin, and gut peptides including ghrelin, PYY and amylin. These changes in turn contribute to low BMD. Studies in anorexia nervosa have demonstrated abnormalities in bone microarchitecture and strength, and an association between increased marrow fat and decreased BMD. One study in adolescents reported an improvement in BMD following physiologic estrogen replacement, and another in adults demonstrated improved BMD following risedronate administration. Brown adipose tissue is reduced in anorexia nervosa, consistent with an adaptive response to the energy deficit state. Summary Anorexia nervosa is associated with widespread physiologic adaptations to the underlying state of undernutrition. Hormonal changes in anorexia nervosa affect BMD adversely. Further investigation is underway to optimize therapeutic strategies for low BMD. PMID:24275621

A PHYSIOLOGICALLY BASED PHARMACOKINETIC (PBPK) MODEL FOR intravenous and ingested DIMETHYLARSINIC ACID (DMAV) IN MICE.

EPA Science Inventory

A physiologically based pharmacokinetic (PBPK) model for the organoarsenical dimethylarsinic acid (DMA(V)) was developed in mice. The model was calibrated using tissue time course data from multiple tissues in mice administered DMA(V) intravenously. The final model structure was ...

Facilitating the transition from physiology to hospital wards through an interdisciplinary case study of septic shock.

PubMed

Li, Albert S; Berger, Kenneth I; Schwartz, David R; Slater, William R; Goldfarb, David S

2014-04-12

In order to develop clinical reasoning, medical students must be able to integrate knowledge across traditional subject boundaries and multiple disciplines. At least two dimensions of integration have been identified: horizontal integration, bringing together different disciplines in considering a topic; and vertical integration, bridging basic science and clinical practice. Much attention has been focused on curriculum overhauls, but our approach is to facilitate horizontal and vertical integration on a smaller scale through an interdisciplinary case study discussion and then to assess its utility. An interdisciplinary case study discussion about a critically ill patient was implemented at the end of an organ system-based, basic sciences module at New York University School of Medicine. Three clinical specialists-a cardiologist, a pulmonologist, and a nephrologist-jointly led a discussion about a complex patient in the intensive care unit with multiple medical problems secondary to septic shock. The discussion emphasized the physiologic underpinnings behind the patient's presentation and the physiologic considerations across the various systems in determining proper treatment. The discussion also highlighted the interdependence between the cardiovascular, respiratory, and renal systems, which were initially presented in separate units. After the session students were given a brief, anonymous three-question free-response questionnaire in which they were asked to evaluate and freely comment on the exercise. Students not only took away physiological principles but also gained an appreciation for various thematic lessons for bringing basic science to the bedside, especially horizontal and vertical integration. The response of the participants was overwhelmingly positive with many indicating that the exercise integrated the material across organ systems, and strengthened their appreciation of the role of physiology in understanding disease presentations and guiding appropriate therapy. Horizontal and vertical integration can be presented effectively through a single-session case study, with complex patient cases involving multiple organ systems providing students opportunities to integrate their knowledge across organ systems while emphasizing the importance of physiology in clinical reasoning. Furthermore, having several clinicians from different specialties discuss the case together can reinforce the matter of integration across multiple organ systems and disciplines in students' minds.

Facilitating the transition from physiology to hospital wards through an interdisciplinary case study of septic shock

PubMed Central

2014-01-01

Background In order to develop clinical reasoning, medical students must be able to integrate knowledge across traditional subject boundaries and multiple disciplines. At least two dimensions of integration have been identified: horizontal integration, bringing together different disciplines in considering a topic; and vertical integration, bridging basic science and clinical practice. Much attention has been focused on curriculum overhauls, but our approach is to facilitate horizontal and vertical integration on a smaller scale through an interdisciplinary case study discussion and then to assess its utility. Methods An interdisciplinary case study discussion about a critically ill patient was implemented at the end of an organ system-based, basic sciences module at New York University School of Medicine. Three clinical specialists—a cardiologist, a pulmonologist, and a nephrologist—jointly led a discussion about a complex patient in the intensive care unit with multiple medical problems secondary to septic shock. The discussion emphasized the physiologic underpinnings behind the patient’s presentation and the physiologic considerations across the various systems in determining proper treatment. The discussion also highlighted the interdependence between the cardiovascular, respiratory, and renal systems, which were initially presented in separate units. After the session students were given a brief, anonymous three-question free-response questionnaire in which they were asked to evaluate and freely comment on the exercise. Results Students not only took away physiological principles but also gained an appreciation for various thematic lessons for bringing basic science to the bedside, especially horizontal and vertical integration. The response of the participants was overwhelmingly positive with many indicating that the exercise integrated the material across organ systems, and strengthened their appreciation of the role of physiology in understanding disease presentations and guiding appropriate therapy. Conclusions Horizontal and vertical integration can be presented effectively through a single-session case study, with complex patient cases involving multiple organ systems providing students opportunities to integrate their knowledge across organ systems while emphasizing the importance of physiology in clinical reasoning. Furthermore, having several clinicians from different specialties discuss the case together can reinforce the matter of integration across multiple organ systems and disciplines in students’ minds. PMID:24725336

Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: focus on the cancer hallmark of tumor angiogenesis

PubMed Central

Hu, Zhiwei; Brooks, Samira A.; Dormoy, Valérian; Hsu, Chia-Wen; Hsu, Hsue-Yin; Lin, Liang-Tzung; Massfelder, Thierry; Rathmell, W. Kimryn; Xia, Menghang; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Brown, Dustin G.; Prudhomme, Kalan R.; Colacci, Annamaria; Hamid, Roslida A.; Mondello, Chiara; Raju, Jayadev; Ryan, Elizabeth P.; Woodrick, Jordan; Scovassi, A. Ivana; Singh, Neetu; Vaccari, Monica; Roy, Rabindra; Forte, Stefano; Memeo, Lorenzo; Salem, Hosni K.; Lowe, Leroy; Jensen, Lasse; Bisson, William H.; Kleinstreuer, Nicole

2015-01-01

One of the important ‘hallmarks’ of cancer is angiogenesis, which is the process of formation of new blood vessels that are necessary for tumor expansion, invasion and metastasis. Under normal physiological conditions, angiogenesis is well balanced and controlled by endogenous proangiogenic factors and antiangiogenic factors. However, factors produced by cancer cells, cancer stem cells and other cell types in the tumor stroma can disrupt the balance so that the tumor microenvironment favors tumor angiogenesis. These factors include vascular endothelial growth factor, endothelial tissue factor and other membrane bound receptors that mediate multiple intracellular signaling pathways that contribute to tumor angiogenesis. Though environmental exposures to certain chemicals have been found to initiate and promote tumor development, the role of these exposures (particularly to low doses of multiple substances), is largely unknown in relation to tumor angiogenesis. This review summarizes the evidence of the role of environmental chemical bioactivity and exposure in tumor angiogenesis and carcinogenesis. We identify a number of ubiquitous (prototypical) chemicals with disruptive potential that may warrant further investigation given their selectivity for high-throughput screening assay targets associated with proangiogenic pathways. We also consider the cross-hallmark relationships of a number of important angiogenic pathway targets with other cancer hallmarks and we make recommendations for future research. Understanding of the role of low-dose exposure of chemicals with disruptive potential could help us refine our approach to cancer risk assessment, and may ultimately aid in preventing cancer by reducing or eliminating exposures to synergistic mixtures of chemicals with carcinogenic potential. PMID:26106137

Basic leucine zipper transcription factor SlbZIP1 mediates salt and drought stress tolerance in tomato.

PubMed

Zhu, Mingku; Meng, Xiaoqing; Cai, Jing; Li, Ge; Dong, Tingting; Li, Zongyun

2018-05-08

Basic region/leucine zipper (bZIP) transcription factors perform as crucial regulators in ABA-mediated stress response in plants. Nevertheless, the functions for most bZIP family members in tomato remain to be deciphered. Here we examined the functional characterization of SlbZIP1 under salt and drought stresses in tomato. Silencing of SlbZIP1 in tomato resulted in reduced expression of multiple ABA biosynthesis- and signal transduction-related genes in transgenic plants. In stress assays, SlbZIP1-RNAi transgenic plants exhibited reduced tolerance to salt and drought stresses compared with WT plants, as are evaluated by multiple physiological parameters associated with stress responses, such as decreased ABA, chlorophyll contents and CAT activity, and increased MDA content. In addition, RNA-seq analysis of transgenic plants revealed that the transcription levels of multiple genes encoding defense proteins related to responses to abiotic stress (e.g. endochitinase, peroxidases, and lipid transfer proteins) and biotic stress (e.g. pathogenesis-related proteins) were downregulated in SlbZIP1-RNAi plants, suggesting that SlbZIP1 plays a role in regulating the genes related to biotic and abiotic stress response. Collectively, the data suggest that SlbZIP1 exerts an essential role in salt and drought stress tolerance through modulating an ABA-mediated pathway, and SlbZIP1 may hold potential applications in the engineering of salt- and drought-tolerant tomato cultivars.

A general enhancement of autonomic and cortisol responses during social evaluative threat.

PubMed

Bosch, Jos A; de Geus, Eco J C; Carroll, Douglas; Goedhart, Annebet D; Anane, Leila A; van Zanten, Jet J Veldhuizen; Helmerhorst, Eva J; Edwards, Kate M

2009-10-01

To examine the Social Self Preservation Theory, which predicts that stressors involving social evaluative threat (SET) characteristically activate the hypothalamic-pituitary-adrenal (HPA) axis. The idea that distinct psychosocial factors may underlie specific patterns of neuroendocrine stress responses has been a topic of recurrent debate. Sixty-one healthy university students (n = 31 females) performed a challenging speech task in one of three conditions that aimed to impose increasing levels of SET: performing the task alone (no social evaluation), with one evaluating observer, or with four evaluating observers. Indices of sympathetic (preejection period) and parasympathetic (heart rate variability) cardiac drive were obtained by impedance- and electrocardiography. Salivary cortisol was used to index HPA activity. Questionnaires assessed affective responses. Affective responses (shame/embarrassment, anxiety, negative affect, and self-esteem), cortisol, heart rate, sympathetic and parasympathetic activation all differentiated evaluative from nonevaluative task conditions (p < .001). The largest effect sizes were observed for cardiac autonomic responses. Physiological reactivity increased in parallel with increasing audience size (p < .001). An increase in cortisol was predicted by sympathetic activation during the task (p < .001), but not by affective responses. It would seem that SET determines the magnitude, rather than the pattern, of physiological activation. This potential to perturb broadly multiple physiological systems may help explain why social stress has been associated with a range of health outcomes. We propose a threshold-activation model as a physiological explanation for why engaging stressors, such as those involving social evaluation or uncontrollability, may seem to induce selectively cortisol release.

Heart rate variation and electroencephalograph--the potential physiological factors for thermal comfort study.

PubMed

Yao, Y; Lian, Z; Liu, W; Jiang, C; Liu, Y; Lu, H

2009-04-01

Human thermal comfort researches mainly focus on the relation between the environmental factors (e.g. ambient temperature, air humidity, and air velocity, etc.) and the thermal comfort sensation based on a large amount of subjective field investigations. Although some physiological factors, such as skin temperature and metabolism were used in many thermal comfort models,they are not enough to establish a perfect thermal comfort model. In this paper,another two physiological factors, i.e. heart rate variation (HRV) and electroencephalograph (EEG), are explored for the thermal comfort study. Experiments were performed to investigate how these physiological factors respond to the environmental temperatures, and what is the relationship between HRV and EEG and thermal comfort. The experimental results indicate that HRV and EEG may be related to thermal comfort, and they may be useful to understand the mechanism of thermal comfort.

Predicting musically induced emotions from physiological inputs: linear and neural network models.

PubMed

Russo, Frank A; Vempala, Naresh N; Sandstrom, Gillian M

2013-01-01

Listening to music often leads to physiological responses. Do these physiological responses contain sufficient information to infer emotion induced in the listener? The current study explores this question by attempting to predict judgments of "felt" emotion from physiological responses alone using linear and neural network models. We measured five channels of peripheral physiology from 20 participants-heart rate (HR), respiration, galvanic skin response, and activity in corrugator supercilii and zygomaticus major facial muscles. Using valence and arousal (VA) dimensions, participants rated their felt emotion after listening to each of 12 classical music excerpts. After extracting features from the five channels, we examined their correlation with VA ratings, and then performed multiple linear regression to see if a linear relationship between the physiological responses could account for the ratings. Although linear models predicted a significant amount of variance in arousal ratings, they were unable to do so with valence ratings. We then used a neural network to provide a non-linear account of the ratings. The network was trained on the mean ratings of eight of the 12 excerpts and tested on the remainder. Performance of the neural network confirms that physiological responses alone can be used to predict musically induced emotion. The non-linear model derived from the neural network was more accurate than linear models derived from multiple linear regression, particularly along the valence dimension. A secondary analysis allowed us to quantify the relative contributions of inputs to the non-linear model. The study represents a novel approach to understanding the complex relationship between physiological responses and musically induced emotion.

Challenges for the development of a biotic ligand model predicting copper toxicity in estuaries and seas.

PubMed

de Polo, Anna; Scrimshaw, Mark D

2012-02-01

An effort is ongoing to develop a biotic ligand model (BLM) that predicts copper (Cu) toxicity in estuarine and marine environments. At present, the BLM accounts for the effects of water chemistry on Cu speciation, but it does not consider the influence of water chemistry on the physiology of the organisms. We discuss how chemistry affects Cu toxicity not only by controlling its speciation, but also by affecting the osmoregulatory physiology of the organism, which varies according to salinity. In an attempt to understand the mechanisms of Cu toxicity and predict its impacts, we explore the hypothesis that the common factor linking the main toxic effects of Cu is the enzyme carbonic anhydrase (CA), because it is a Cu target with multiple functions and salinity-dependent expression and activity. According to this hypothesis, the site of action of Cu in marine fish may be not only the gill, but also the intestine, because in this tissue CA plays an important role in ion transport and water adsorption. Therefore, the BLM of Cu toxicity to marine fish should also consider the intestine as a biotic ligand. Finally, we underline the need to incorporate the osmotic gradient into the BLM calculations to account for the influence of physiology on Cu toxicity. Copyright © 2011 SETAC.

Physiological frailty index (PFI): quantitative in-life estimate of individual biological age in mice.

PubMed

Antoch, Marina P; Wrobel, Michelle; Kuropatwinski, Karen K; Gitlin, Ilya; Leonova, Katerina I; Toshkov, Ilia; Gleiberman, Anatoli S; Hutson, Alan D; Chernova, Olga B; Gudkov, Andrei V

2017-03-19

The development of healthspan-extending pharmaceuticals requires quantitative estimation of age-related progressive physiological decline. In humans, individual health status can be quantitatively assessed by means of a frailty index (FI), a parameter which reflects the scale of accumulation of age-related deficits. However, adaptation of this methodology to animal models is a challenging task since it includes multiple subjective parameters. Here we report a development of a quantitative non-invasive procedure to estimate biological age of an individual animal by creating physiological frailty index (PFI). We demonstrated the dynamics of PFI increase during chronological aging of male and female NIH Swiss mice. We also demonstrated acceleration of growth of PFI in animals placed on a high fat diet, reflecting aging acceleration by obesity and provide a tool for its quantitative assessment. Additionally, we showed that PFI could reveal anti-aging effect of mTOR inhibitor rapatar (bioavailable formulation of rapamycin) prior to registration of its effects on longevity. PFI revealed substantial sex-related differences in normal chronological aging and in the efficacy of detrimental (high fat diet) or beneficial (rapatar) aging modulatory factors. Together, these data introduce PFI as a reliable, non-invasive, quantitative tool suitable for testing potential anti-aging pharmaceuticals in pre-clinical studies.

Predicting preschoolers' social-cognitive play behavior: attachment, peers, temperament, and physiological regulation.

PubMed

Porter, Christin L

2009-04-01

Research on children's social-cognitive play typologies (i.e., active and passive forms of solitary and social play) suggests links of early play behaviors and later social development and risk status. To date, few studies have examined simultaneously suspected links between children's social-cognitive play types and factors believed to shape these early social-play behaviors. This study examined a simultaneous model of individual (temperament, physiology) and relational variables (attachment, peer networks) believed to influence children's social-cognitive play types, including individual characteristics drawn from the Child Behavior Questionnaire which measures dimensions of shyness and impulsivity, a lab-based assessment of social withdrawal, and physiological markers linked to social regulation (cardiac vagal tone and vagal regulation). Children's attachment status to parents was gathered using Q-Sort methodology, and a measure of previous peer network size was obtained from parents' reports to examine potential links between relational history and social-cognitive play types. Predictive discriminant function analysis showed that children's (N = 54, age range 35 to 58 months) social-cognitive play was better predicted on the basis of multiple independent variables than individual, zero-order relations. When predicting children's social-cognitive play typologies, a multidimensional view which encompasses both individual characteristics and social-relational variables may best predict social -cognitive play types and help understanding of children's social trajectories.

H2S Regulates Hypobaric Hypoxia-Induced Early Glio-Vascular Dysfunction and Neuro-Pathophysiological Effects

PubMed Central

Kumar, Gaurav; Chhabra, Aastha; Mishra, Shalini; Kalam, Haroon; Kumar, Dhiraj; Meena, Ramniwas; Ahmad, Yasmin; Bhargava, Kalpana; Prasad, Dipti N.; Sharma, Manish

2016-01-01

Hypobaric Hypoxia (HH) is an established risk factor for various neuro-physiological perturbations including cognitive impairment. The origin and mechanistic basis of such responses however remain elusive. We here combined systems level analysis with classical neuro-physiological approaches, in a rat model system, to understand pathological responses of brain to HH. Unbiased ‘statistical co-expression networks’ generated utilizing temporal, differential transcriptome signatures of hippocampus—centrally involved in regulating cognition—implicated perturbation of Glio-Vascular homeostasis during early responses to HH, with concurrent modulation of vasomodulatory, hemostatic and proteolytic processes. Further, multiple lines of experimental evidence from ultra-structural, immuno-histological, substrate-zymography and barrier function studies unambiguously supported this proposition. Interestingly, we show a significant lowering of H2S levels in the brain, under chronic HH conditions. This phenomenon functionally impacted hypoxia-induced modulation of cerebral blood flow (hypoxic autoregulation) besides perturbing the strength of functional hyperemia responses. The augmentation of H2S levels, during HH conditions, remarkably preserved Glio-Vascular homeostasis and key neuro-physiological functions (cerebral blood flow, functional hyperemia and spatial memory) besides curtailing HH-induced neuronal apoptosis in hippocampus. Our data thus revealed causal role of H2S during HH-induced early Glio-Vascular dysfunction and consequent cognitive impairment. PMID:27211559

Techniques for measuring animal physiological and behavioral responses with respect to the environment

USDA-ARS?s Scientific Manuscript database

Environmental effects cause animal production inefficiencies and animal well-being issues. Thus, many experiments have been designed to understand thermal stress and to test different means to relieve it. There are multiple physiological responses and behavior/activities that can be measured to di...

Stress Physiology in Infancy and Early Childhood: Cortisol Flexibility, Attunement and Coordination.

PubMed

Atkinson, L; Jamieson, B; Khoury, J; Ludmer, J; Gonzalez, A

2016-08-01

Research on stress physiology in infancy has assumed increasing importance due to its lifelong implications. In this review, we focus on measurement of hypothalamic-pituitary-adrenal (HPA) function, in particular, and on complementary autonomic processes. We suggest that the measure of HPA function has been overly exclusive, focusing on individual reactivity to single, pragmatically selected laboratory challenges. We advocate use of multiple, strategically chosen challenges and within-subject designs. By administering one challenge that typically does not provoke reactivity and another that does, it is possible to represent allostatic load in terms of "flexibility," the capacity to titrate response to challenge. We also recommend assessing infant reactivity in the context of the primary caregiver's physiological function. Infant-mother "attunement" is central to developmental psychology, permeating diverse developmental domains with varied consequences. A review of adrenocortical attunement suggests that attunement is a reliable process, manifest across varied populations. However, attunement appears stronger in the context of more highly stressful circumstances, such that administration of multiple, selected challenges may help evaluate the degree to which individuals titrate attunement to challenge and determine the correlates of this differential attunement. Finally, we advocate studying the "coordination" of HPA function with other aspects of stress physiology and variation in the degree of this coordination. The use of multiple stressors is important here because each stress system is differentially sensitive to different types of challenge. Therefore, use of single stressors in between-subject designs impedes full recognition of the role played by each system. Overall, we recommend measure of flexibility, attunement, and coordination in the context of multiple challenges to capture allostasis in environmental and physiological context. The simultaneous use of such inclusive and integrative metrics may yield more reliable findings than has hitherto been the case. The interrelation of these metrics can be understood in the context of the adaptive calibration model.. © 2016 British Society for Neuroendocrinology.

Assessment of workload using NASA Task Load Index in perianesthesia nursing.

PubMed

Young, Gloria; Zavelina, Lyubov; Hooper, Vallire

2008-04-01

According to the Institute of Medicine (IOM), as many as 44,000 to 98,000 people in the United States die in hospitals every year due to medical errors. Multiple physiological and psychological factors can impact the health care provider's attention span, making medical errors more likely. Some of these factors include increased workload, fatigue, cognitive overload, ineffective interpersonal communications, and faulty information processing. Postanesthesia nurses, responsible for providing care to unstable patients emerging from anesthesia with multiple life-threatening conditions, must make critical decisions on a minute-by-minute basis. The current ASPAN Patient Classification/Recommended Staffing Guidelines does not adequately take into account varying care requirements among the patients. If a tool could be found that effectively evaluated staff's workload, ongoing assessment would be enhanced and resources better used. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX), a multifaceted tool for evaluating perceptual (subjective) workload, has seen extensive applications and is widely regarded as the strongest tool available for reporting perceptions of workload. This article will survey various uses of the NASA-TLX and consider the potential uses for this tool in perianesthesia nursing.

Nanostructured and thermoresponsive recombinant biopolymer-based microcapsules for the delivery of active molecules.

PubMed

Costa, Rui R; Custódio, Catarina A; Arias, Francisco J; Rodríguez-Cabello, José C; Mano, João F

2013-10-01

Multilayer capsules conceived at the nano- and microscales are receiving increasing interest due to their potential role as carriers of biomolecules for drug delivery and tissue engineering. Herein we report the construction of microcapsules by the sequential adsorption of chitosan and a biomimetic elastin-like recombinamer into nanostructured layers on inorganic microparticle templates. The release profile of bovine serum albumin, which was studied at 25 and 37 °C, shows higher retention and Fickian diffusion at physiological temperature. The self-assembled multilayers act as a barrier and allowed for sustained release over 14 days. The capsules studied are non-cytotoxic towards L929 cells, thereby suggesting multiple applications in the fields of biotechnology and bioengineering, where high control of the delivery of therapeutics and growth/differentiation factors is required. In this paper, the construction of microcapsules by sequential adsorption of chitosan and a biomimetic, elastin-like recombinamer into nanostructured layers on inorganic microparticle templates is reported. The layers demonstrated sustained drug release over 14 days. These microcapsules are non-cytotoxic toward L929 cells, suggesting multiple applications where high control of drug or growth factor delivery is required. Copyright © 2013 Elsevier Inc. All rights reserved.

Bed Rest is an Analog to Study the Physiological Changes of Spaceflight and to Evaluate Countermeasures

NASA Technical Reports Server (NTRS)

Pfannenstiel, P.; Ottenbacher, M.; Inniss, A.; Ware, D.; Anderson, K.; Stranges, S.; Keith, K.; Cromwell, R.; Neigut. J.; Powell, D.

2012-01-01

The UTMB/NASA Flight Analog Research Unit is an inpatient unit with a bionutrition kitchen and unique testing areas for studying subjects subjected to 6 degree head-down complete bed rest for prolonged periods as an analog for zero gravity. Bed rest allows study of physiological changes and performance of functional tasks representative of critical interplanetary mission operations and measures of the efficacy of countermeasures designed to protect against the resulting deleterious effects. METHODS/STUDY POPULATION: Subjects are healthy adults 24-55 years old; 60 75 in tall; body mass index 18.5-30; and bone mineral density normal by DXA scan. Over 100 subjects have been studied in 7 campaigns since 2004. The iRAT countermeasure combines high intensity interval aerobic exercises on alternating days with continuous aerobic exercise. Resistance exercise is performed 3 days per week. Subjects are tested on an integrated suite of functional and interdisciplinary physiological tests before and after 70 days of total bed rest. RESULTS/ANTICIPATED RESULTS: It is anticipated that post-bed rest functional performance will be predicted by a weighted combination of sensorimotor, cardiovascular and muscle physiological factors. Control subjects who do not participate in the exercise countermeasure will have significantly greater decreases in these parameters. DISCUSSION/SIGNIFICANCE OF IMPACT: Astronauts experience alterations in multiple physiological systems due to exposure to the microgravity, leading to disruption in the ability to perform functional tasks after reintroduction to a gravitational environment. Current flight exercise countermeasures are not fully protective of cardiovascular, muscle and bone health. There is a need to refine and optimize countermeasures to mitigate health risks associated with long-term space missions.

SR-BI as target in atherosclerosis and cardiovascular disease - A comprehensive appraisal of the cellular functions of SR-BI in physiology and disease.

PubMed

Hoekstra, Menno

2017-03-01

High-density lipoprotein (HDL) is considered an anti-atherogenic lipoprotein species due to its role in reverse cholesterol transport. HDL delivers cholesterol esters to the liver through selective uptake by scavenger receptor class B type I (SR-BI). In line with the protective role for HDL in the context of cardiovascular disease, studies in mice and recently also in humans have shown that a disruption of normal SR-BI function predisposes subjects to the development of atherosclerotic lesions and cardiovascular disease. Although SR-BI function has been studied primarily in the liver, it should be acknowledged that the SR-BI protein is expressed in multiple tissues and cell types across the body, albeit at varying levels between the different tissues. Given that SR-BI is widely expressed throughout the body, multiple cell types and tissues can theoretically contribute to the atheroprotective effect of SR-BI. In this review the different functions of SR-BI in normal physiology are highlighted and the (potential) consequences of cell type-specific disruption of SR-BI function for atherosclerosis and cardiovascular disease susceptibility discussed. It appears that hepatocyte and platelet SR-BI inhibit respectively the development of atherosclerotic lesions and thrombosis, suggesting that SR-BI located on these cell compartments should be regarded as being a protective factor in the context of cardiovascular disease. The relative contribution of SR-BI present on endothelial cells, steroidogenic cells, adipocytes and macrophages to the pathogenesis of atherosclerosis and cardiovascular disease remains less clear, although proper SR-BI function in these cells does appear to influence multiple processes that impact on cardiovascular disease susceptibility. Copyright © 2017 The Author. Published by Elsevier B.V. All rights reserved.

The physiology of spacecraft and space suit atmosphere selection

NASA Astrophysics Data System (ADS)

Waligora, J. M.; Horrigan, D. J.; Nicogossian, A.

The majority of the environmental factors which comprise the spacecraft and space suit environments can be controlled at "Earth normal" values, at optimum values, or at other values decided upon by spacecraft designers. Factors which are considered in arriving at control values and control ranges of these parameters include physiological, engineering, operational cost, and safety considerations. Several of the physiologic considerations, including hypoxia and hyperoxia, hypercapnia, temperature regulation, and decompression sickness are identified and their impact on space craft and space suit atmosphere selection are considered. The past experience in controlling these parameters in U.S. and Soviet spacecraft and space suits and the associated physiological responses are reviewed. Current areas of physiological investigation relating to environmental factors in spacecraft are discussed, particularly decompression sickness which can occur as a result of change in pressure from Earth to spacecraft or spacecraft to space suit. Physiological considerations for long-term lunar or Martian missions will have different impacts on atmosphere selection and may result in the selection of atmospheres different than those currently in use.

Optimal input selection for neural machine interfaces predicting multiple non-explicit outputs.

PubMed

Krepkovich, Eileen T; Perreault, Eric J

2008-01-01

This study implemented a novel algorithm that optimally selects inputs for neural machine interface (NMI) devices intended to control multiple outputs and evaluated its performance on systems lacking explicit output. NMIs often incorporate signals from multiple physiological sources and provide predictions for multidimensional control, leading to multiple-input multiple-output systems. Further, NMIs often are used with subjects who have motor disabilities and thus lack explicit motor outputs. Our algorithm was tested on simulated multiple-input multiple-output systems and on electromyogram and kinematic data collected from healthy subjects performing arm reaches. Effects of output noise in simulated systems indicated that the algorithm could be useful for systems with poor estimates of the output states, as is true for systems lacking explicit motor output. To test efficacy on physiological data, selection was performed using inputs from one subject and outputs from a different subject. Selection was effective for these cases, again indicating that this algorithm will be useful for predictions where there is no motor output, as often is the case for disabled subjects. Further, prediction results generalized for different movement types not used for estimation. These results demonstrate the efficacy of this algorithm for the development of neural machine interfaces.

Respiration and heartbeat monitoring using a distributed pulsed MIMO radar.

PubMed

Walterscheid, Ingo; Smith, Graeme E

2017-07-01

This paper addresses non-contact monitoring of physiological signals induced by respiration and heartbeat. To detect the tiny physiological movements of the chest or other parts of the torso, a Mulitple-Input Multiple-Output (MIMO) radar is used. The spatially distributed transmitters and receivers are able to detect the chest surface movements of one or multiple persons in a room. Due to several bistatic measurements at the same time a robust detection and measuring of the breathing and heartbeat rate is possible. Using an appropriate geometrical configuration of the sensors even a localization of the person is feasible.

The EPOS-CC Score: An Integration of Independent, Tumor- and Patient-Associated Risk Factors to Predict 5-years Overall Survival Following Colorectal Cancer Surgery.

PubMed

Haga, Yoshio; Ikejiri, Koji; Wada, Yasuo; Ikenaga, Masakazu; Koike, Shoichiro; Nakamura, Seiji; Koseki, Masato

2015-06-01

Surgical audit is an essential task for the estimation of postoperative outcome and comparison of quality of care. Previous studies on surgical audits focused on short-term outcomes, such as postoperative mortality. We propose a surgical audit evaluating long-term outcome following colorectal cancer surgery. The predictive model for this audit is designated as 'Estimation of Postoperative Overall Survival for Colorectal Cancer (EPOS-CC)'. Thirty-one tumor-related and physiological variables were prospectively collected in 889 patients undergoing elective resection for colorectal cancer between April 2005 and April 2007 in 16 Japanese hospitals. Postoperative overall survival was assessed over a 5-years period. The EPOS-CC score was established by selecting significant variables in a uni- and multivariate analysis and allocating a risk-adjusted multiplication factor to each variable using Cox regression analysis. For validation, the EPOS-CC score was compared to the predictive power of UICC stage. Inter-hospital variability of the observed-to-estimated 5-years survival was assessed to estimate quality of care. Among the 889 patients, 804 (90%) completed the 5-years follow-up. Univariate analysis displayed a significant correlation with 5-years survival for 14 physiological and nine tumor-related variables (p < 0.005). Highly significant p-values below 0.0001 were found for age, ASA score, severe pulmonary disease, respiratory history, performance status, hypoalbuminemia, alteration of hemoglobin, serum sodium level, and for all histological variables except tumor location. Age, TNM stage, lymphatic invasion, performance status, and serum sodium level were independent variables in the multivariate analysis and were entered the EPOS-CC model for the prediction of survival. Risk-adjusted multiplication factors between 1.5 (distant metastasis) and 0.16 (serum sodium level) were accorded to the different variables. The predictive power of EPOS-CC was superior to the one of UICC stage; area under the curve 0.87, 95% CI 0.85-0.90 for EPOS-CC, and 0.80, 0.76-0.83 for UICC stage, p < 0.001. Quality of care did not differ between hospitals. The EPOS-CC score including the independent variables age, performance status, serum sodium level, TNM stage, and lymphatic invasion is superior to the UICC stage in the prediction of 5-years overall survival. This higher accuracy might be explained by the inclusion of physiological factors, thus also taking non-tumor-associated deaths into account. Furthermore, EPOS-CC score may compare quality of care among different institutions. Future studies are necessary to further evaluate this score and help improving the prediction of long-term survival following colorectal cancer surgery.

Physiologic and thermal responses of male and female patients with multiple sclerosis to head and neck cooling

NASA Technical Reports Server (NTRS)

Ku, Y. T.; Montgomery, L. D.; Wenzel, K. C.; Webbon, B. W.; Burks, J. S.

1999-01-01

Personal cooling systems are used to alleviate symptoms of multiple sclerosis and to prevent increased core temperature during daily activities. The objective of this study was to determine the thermal and physiologic responses of patients with multiple sclerosis to short-term maximal head and neck cooling. A Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used to cool the head and neck regions of 24 female and 26 male patients with multiple sclerosis in this study. The subjects, seated in an upright position at normal room temperature (approximately 22 degrees C), were cooled for 30 min by the liquid cooling garment, which was operated at its maximum cooling capacity. Oral, right, and left ear temperatures and cooling system parameters were logged manually every 5 min. Forearm, calf, chest, and rectal temperatures, heart rate, and respiration rate were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. This protocol was performed during the winter and summer to investigate the seasonal differences in the way patients with multiple sclerosis respond to head and neck cooling. No significant differences were found between the male and female subject group's mean rectal or oral temperature responses during any phase of the experiment. The mean oral temperature decreased significantly (P < 0.05) for both groups approximately 0.3 degrees C after 30 min of cooling and continued to decrease further (approximately 0.1-0.2 degrees C) for a period of approximately 15 min after removal of the cooling helmet. The mean rectal temperatures decreased significantly (P < 0.05) in both male and female subjects in the winter studies (approximately 0.2-0.3 degrees C) and for the male subjects during the summer test (approximately 0.2 degrees C). However, the rectal temperature of the female subjects did not change significantly during any phase of the summer test. These data indicate that head and neck cooling may, in general, be used to reduce the oral and body temperatures of both male and female patients with multiple sclerosis by the approximate amount needed for symptomatic relief as shown by other researchers. However, thermal response of patients with multiple sclerosis may be affected by gender and seasonal factors, which should be considered in the use of liquid cooling therapy.

Age Learning Factors Affecting Pilot Education.

ERIC Educational Resources Information Center

Torbert, Brison

This document, intended for pilot education and flight safety specialists, consists chiefly of a review of the literature on physiological factors that affect pilot education and an examination of environmental factors that should be scrutinized in order to improve the effectiveness of aviation learning facilities. The physiological factors…

Multilevel functional genomics data integration as a tool for understanding physiology: a network biology perspective.

PubMed

Davidsen, Peter K; Turan, Nil; Egginton, Stuart; Falciani, Francesco

2016-02-01

The overall aim of physiological research is to understand how living systems function in an integrative manner. Consequently, the discipline of physiology has since its infancy attempted to link multiple levels of biological organization. Increasingly this has involved mathematical and computational approaches, typically to model a small number of components spanning several levels of biological organization. With the advent of "omics" technologies, which can characterize the molecular state of a cell or tissue (intended as the level of expression and/or activity of its molecular components), the number of molecular components we can quantify has increased exponentially. Paradoxically, the unprecedented amount of experimental data has made it more difficult to derive conceptual models underlying essential mechanisms regulating mammalian physiology. We present an overview of state-of-the-art methods currently used to identifying biological networks underlying genomewide responses. These are based on a data-driven approach that relies on advanced computational methods designed to "learn" biology from observational data. In this review, we illustrate an application of these computational methodologies using a case study integrating an in vivo model representing the transcriptional state of hypoxic skeletal muscle with a clinical study representing muscle wasting in chronic obstructive pulmonary disease patients. The broader application of these approaches to modeling multiple levels of biological data in the context of modern physiology is discussed. Copyright © 2016 the American Physiological Society.

Assessing interactions among multiple physiological systems during walking outside a laboratory: An Android based gait monitor

PubMed Central

Sejdić, E.; Millecamps, A.; Teoli, J.; Rothfuss, M. A.; Franconi, N. G.; Perera, S.; Jones, A. K.; Brach, J. S.; Mickle, M. H.

2015-01-01

Gait function is traditionally assessed using well-lit, unobstructed walkways with minimal distractions. In patients with subclinical physiological abnormalities, these conditions may not provide enough stress on their ability to adapt to walking. The introduction of challenging walking conditions in gait can induce responses in physiological systems in addition to the locomotor system. There is a need for a device that is capable of monitoring multiple physiological systems in various walking conditions. To address this need, an Android-based gait-monitoring device was developed that enabled the recording of a patient's physiological systems during walking. The gait-monitoring device was tested during self-regulated overground walking sessions of fifteen healthy subjects that included 6 females and 9 males aged 18 to 35 years. The gait-monitoring device measures the patient's stride interval, acceleration, electrocardiogram, skin conductance and respiratory rate. The data is stored on an Android phone and is analyzed offline through the extraction of features in the time, frequency and time-frequency domains. The analysis of the data depicted multisystem physiological interactions during overground walking in healthy subjects. These interactions included locomotion-electrodermal, locomotion-respiratory and cardiolocomotion couplings. The current results depicting strong interactions between the locomotion system and the other considered systems (i.e., electrodermal, respiratory and cardivascular systems) warrant further investigation into multisystem interactions during walking, particularly in challenging walking conditions with older adults. PMID:26390946

Reduced Salinity Improves Marine Food Availability With Positive Feedbacks on pH in a Tidally-Dominated Estuary

NASA Astrophysics Data System (ADS)

Lowe, A. T.; Roberts, E. A.; Galloway, A. W. E.

2016-02-01

Coastal regions around the world are changing rapidly, generating many physiological stressors for marine organisms. Food availability, a major factor determining physiological condition of marine organisms, in these systems reflects the influence of biological and environmental factors, and will likely respond dramatically to long-term changes. Using observations of phytoplankton, detritus, and their corresponding fatty acids and stable isotopes of carbon, nitrogen and sulfur, we identified environmental drivers of pelagic food availability and quality along a salinity gradient in a large tidally influenced estuary (San Juan Archipelago, Salish Sea, USA). Variation in chlorophyll a (Chl a), biomarkers and environmental conditions exhibited a similar range at both tidal and seasonal scales, highlighting a tide-related mechanism controlling productivity that is important to consider for long-term monitoring. Multiple parameters of food availability were inversely and non-linearly correlated to salinity, such that availability of high-quality (based on abundance, essential fatty acid concentration and C:N) seston increased below a salinity threshold of 30. The increased marine productivity was associated with increased pH and dissolved oxygen (DO) at lower salinity. Based on this observation we predicted that a decrease of salinity to below the threshold would result in higher Chl a, temperature, DO and pH across a range of temporal and spatial scales, and tested the prediction with a meta-analysis of available data. At all scales, these variables showed significant and consistent increases related to the salinity threshold. This finding provides important context to the increased frequency of below-threshold salinity over the last 71 years in this region, suggesting greater food availability with positive feedbacks on DO and pH. Together, these findings indicate that many of the environmental factors predicted to increase physiological stress to benthic suspension feeders (e.g. decreased salinity) may simultaneously and paradoxically improve conditions for benthic organisms.

The DAF-16 FOXO Transcription Factor Regulates natc-1 to Modulate Stress Resistance in Caenorhabditis elegans, Linking Insulin/IGF-1 Signaling to Protein N-Terminal Acetylation

PubMed Central

Warnhoff, Kurt; Murphy, John T.; Kumar, Sandeep; Schneider, Daniel L.; Peterson, Michelle; Hsu, Simon; Guthrie, James; Robertson, J. David; Kornfeld, Kerry

2014-01-01

The insulin/IGF-1 signaling pathway plays a critical role in stress resistance and longevity, but the mechanisms are not fully characterized. To identify genes that mediate stress resistance, we screened for C. elegans mutants that can tolerate high levels of dietary zinc. We identified natc-1, which encodes an evolutionarily conserved subunit of the N-terminal acetyltransferase C (NAT) complex. N-terminal acetylation is a widespread modification of eukaryotic proteins; however, relatively little is known about the biological functions of NATs. We demonstrated that loss-of-function mutations in natc-1 cause resistance to a broad-spectrum of physiologic stressors, including multiple metals, heat, and oxidation. The C. elegans FOXO transcription factor DAF-16 is a critical target of the insulin/IGF-1 signaling pathway that mediates stress resistance, and DAF-16 is predicted to directly bind the natc-1 promoter. To characterize the regulation of natc-1 by DAF-16 and the function of natc-1 in insulin/IGF-1 signaling, we analyzed molecular and genetic interactions with key components of the insulin/IGF-1 pathway. natc-1 mRNA levels were repressed by DAF-16 activity, indicating natc-1 is a physiological target of DAF-16. Genetic studies suggested that natc-1 functions downstream of daf-16 to mediate stress resistance and dauer formation. Based on these findings, we hypothesize that natc-1 is directly regulated by the DAF-16 transcription factor, and natc-1 is a physiologically significant effector of the insulin/IGF-1 signaling pathway that mediates stress resistance and dauer formation. These studies identify a novel biological function for natc-1 as a modulator of stress resistance and dauer formation and define a functionally significant downstream effector of the insulin/IGF-1 signaling pathway. Protein N-terminal acetylation mediated by the NatC complex may play an evolutionarily conserved role in regulating stress resistance. PMID:25330323

Circadian expression profiles of chromatin remodeling factor genes in Arabidopsis.

PubMed

Lee, Hong Gil; Lee, Kyounghee; Jang, Kiyoung; Seo, Pil Joon

2015-01-01

The circadian clock is a biological time keeper mechanism that regulates biological rhythms to a period of approximately 24 h. The circadian clock enables organisms to anticipate environmental cycles and coordinates internal cellular physiology with external environmental cues. In plants, correct matching of the clock with the environment confers fitness advantages to plant survival and reproduction. Therefore, circadian clock components are regulated at multiple layers to fine-tune the circadian oscillation. Epigenetic regulation provides an additional layer of circadian control. However, little is known about which chromatin remodeling factors are responsible for circadian control. In this work, we analyzed circadian expression of 109 chromatin remodeling factor genes and identified 17 genes that display circadian oscillation. In addition, we also found that a candidate interacts with a core clock component, supporting that clock activity is regulated in part by chromatin modification. As an initial attempt to elucidate the relationship between chromatin modification and circadian oscillation, we identified novel regulatory candidates that provide a platform for future investigations of chromatin regulation of the circadian clock.

Calcium and aluminum impacts on sugar maple physiology in a northern hardwood forest

Treesearch

Joshua M. Halman; Paul G. Schaberg; Gary J. Hawley; Linda H. Pardo; Timothy J. Fahey

2013-01-01

Forests of northeastern North America have been exposed to anthropogenic acidic inputs for decades, resulting in altered cation relations and disruptions to associated physiological processes in multiple tree species, including sugar maple (Acer saccharum Marsh.). In the current study, the impacts of calcium (Ca) and aluminum (Al) additions on mature...

Tissue Physiology and Pathology of Aromatase

PubMed Central

Stocco, Carlos

2011-01-01

Summary Aromatase is expressed in multiple tissues, indicating a crucial role for locally produced oestrogens in the differentiation, regulation and normal function of several organs and processes. This review is an overview of the role of aromatase in different tissues under normal physiological conditions and its contribution to the development of some oestrogen-related pathologies. PMID:22108547

Exercise Hypertension

PubMed Central

Schultz, Martin G.; Sharman, James E.

2014-01-01

Irrespective of apparent ‘normal' resting blood pressure (BP), some individuals may experience an excessive elevation in BP with exercise (i.e. systolic BP ≥210 mm Hg in men or ≥190 mm Hg in women or diastolic BP ≥110 mm Hg in men or women), a condition termed exercise hypertension or a ‘hypertensive response to exercise' (HRE). An HRE is a relatively common condition that is identified during standard exercise stress testing; however, due to a lack of information with respect to the clinical ramifications of an HRE, little value is usually placed on such a finding. In this review, we discuss both the clinical importance and underlying physiological contributors of exercise hypertension. Indeed, an HRE is associated with an increased propensity for target organ damage and also predicts the future development of hypertension, cardiovascular events and mortality, independent of resting BP. Moreover, recent work has highlighted that some of the elevated cardiovascular risks associated with an HRE may be related to high-normal resting BP (pre-hypertension) or ambulatory ‘masked' hypertension and that an HRE may be an early warning signal of abnormal BP control that is otherwise undetected with clinic BP. Whilst an HRE may be amenable to treatment via pharmacological and lifestyle interventions, the exact physiological mechanism of an HRE remains elusive, but it is likely a manifestation of multiple factors including large artery stiffness, increased peripheral resistance, neural circulatory control and metabolic irregularity. Future research focus may be directed towards determining threshold values to denote the increased risk associated with an HRE and further resolution of the underlying physiological factors involved in the pathogenesis of an HRE. PMID:26587435

The susceptibility and resilience of corals to thermal stress: adaptation, acclimatization or both?

PubMed

Weis, Virginia M

2010-04-01

Coral reefs are threatened with worldwide decline from multiple factors, chief among them climate change (Hughes et al. 2003; Hoegh-Guldberg et al. 2007). The foundation of coral reefs is an endosymbiosis between coral hosts and their resident photosynthetic dinoflagellates (genus Symbiodinium) and this partnership (or holobiont) is exquisitely sensitive to temperature stress. The primary response to hyperthermic stress is coral bleaching, which is the loss of symbionts from coral tissues-the collapse of the symbiosis (Weis 2008). Bleaching can result in increased coral mortality which can ultimately lead to severely compromised reef health (Hoegh-Guldberg et al. 2007). Despite this grim picture of coral bleaching and reef degradation, coral susceptibility to stress and bleaching is highly variable (Coles & Brown 2003). There is enormous interest in discovering the factors that determine susceptibility in order to help us predict if and how corals will survive a period of rapid global warming. In this issue, Barshis et al. (2010) examine the ecophysiological and genetic basis for differential responses to stress in Porites lobata in American Samoa. They combine a reciprocal transplant experimental design between two neighbouring, but very different reef environments with state-of-the-art physiological biomarkers and molecular genetic markers for both partners to tease apart the contribution of environmental and fixed influences on stress susceptibility. Their results suggest the presence of a fixed, rather than environmental effect on expression of ubiquitin conjugates, one key marker for physiological stress response. In addition, the authors show genetic differentiation in host populations between the two sites suggesting strong selection for physiological adaptation to differing environments across small geographic distances. These conclusions point the study of coral resilience and susceptibility in a new direction.

The effect of water temperature and flow on respiration in barnacles: patterns of mass transfer versus kinetic limitation.

PubMed

Nishizaki, Michael T; Carrington, Emily

2014-06-15

In aquatic systems, physiological processes such as respiration, photosynthesis and calcification are potentially limited by the exchange of dissolved materials between organisms and their environment. The nature and extent of physiological limitation is, therefore, likely to be dependent on environmental conditions. Here, we assessed the metabolic sensitivity of barnacles under a range of water temperatures and velocities, two factors that influence their distribution. Respiration rates increased in response to changes in temperature and flow, with an interaction where flow had less influence on respiration at low temperatures, and a much larger effect at high temperatures. Model analysis suggested that respiration is mass transfer limited under conditions of low velocity (<7.5 cm (-1)) and high temperature (20-25°C). In contrast, limitation by uptake reaction kinetics, when the biotic capacity of barnacles to absorb and process oxygen is slower than its physical delivery by mass transport, prevailed at high flows (40-150 cm s(-1)) and low temperatures (5-15°C). Moreover, there are intermediate flow-temperature conditions where both mass transfer and kinetic limitation are important. Behavioral monitoring revealed that barnacles fully extend their cirral appendages at low flows and display abbreviated 'testing' behaviors at high flows, suggesting some form of mechanical limitation. In low flow-high temperature treatments, however, barnacles displayed distinct 'pumping' behaviors that may serve to increase ventilation. Our results suggest that in slow-moving waters, respiration may become mass transfer limited as temperatures rise, whereas faster flows may serve to ameliorate the effects of elevated temperatures. Moreover, these results underscore the necessity for approaches that evaluate the combined effects of multiple environmental factors when examining physiological and behavioral performance. © 2014. Published by The Company of Biologists Ltd.

The complex genetics of human insulin-like growth factor 2 are not reflected in public databases.

PubMed

Rotwein, Peter

2018-03-23

Recent advances in genetics present unique opportunities for enhancing knowledge about human physiology and disease susceptibility. Understanding this information at the individual gene level is challenging and requires extracting, collating, and interpreting data from a variety of public gene repositories. Here, I illustrate this challenge by analyzing the gene for human insulin-like growth factor 2 ( IGF2 ) through the lens of several databases. IGF2, a 67-amino acid secreted peptide, is essential for normal prenatal growth and is involved in other physiological and pathophysiological processes in humans. Surprisingly, none of the genetic databases accurately described or completely delineated human IGF2 gene structure or transcript expression, even though all relevant information could be found in the published literature. Although IGF2 shares multiple features with the mouse Igf2 gene, it has several unique properties, including transcription from five promoters. Both genes undergo parental imprinting, with IGF2 / Igf2 being expressed primarily from the paternal chromosome and the adjacent H19 gene from the maternal chromosome. Unlike mouse Igf2 , whose expression declines after birth, human IGF2 remains active throughout life. This characteristic has been attributed to a unique human gene promoter that escapes imprinting, but as shown here, it involves several different promoters with distinct tissue-specific expression patterns. Because new testable hypotheses could lead to critical insights into IGF2 actions in human physiology and disease, it is incumbent that our fundamental understanding is accurate. Similar challenges affecting knowledge of other human genes should promote attempts to critically evaluate, interpret, and correct human genetic data in publicly available databases. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Physiological and physical characteristics of elite dragon boat paddlers.

PubMed

Ho, Sarah R; Smith, Richard M; Chapman, Philip G; Sinclair, Peter J; Funato, Kazuo

2013-01-01

The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.

Palmitic Acid: Physiological Role, Metabolism and Nutritional Implications

PubMed Central

Carta, Gianfranca; Murru, Elisabetta; Banni, Sebastiano; Manca, Claudia

2017-01-01

Palmitic acid (PA) has been for long time negatively depicted for its putative detrimental health effects, shadowing its multiple crucial physiological activities. PA is the most common saturated fatty acid accounting for 20–30% of total fatty acids in the human body and can be provided in the diet or synthesized endogenously via de novo lipogenesis (DNL). PA tissue content seems to be controlled around a well-defined concentration, and changes in its intake do not influence significantly its tissue concentration because the exogenous source is counterbalanced by PA endogenous biosynthesis. Particular physiopathological conditions and nutritional factors may strongly induce DNL, resulting in increased tissue content of PA and disrupted homeostatic control of its tissue concentration. The tight homeostatic control of PA tissue concentration is likely related to its fundamental physiological role to guarantee membrane physical properties but also to consent protein palmitoylation, palmitoylethanolamide (PEA) biosynthesis, and in the lung an efficient surfactant activity. In order to maintain membrane phospholipids (PL) balance may be crucial an optimal intake of PA in a certain ratio with unsaturated fatty acids, especially PUFAs of both n-6 and n-3 families. However, in presence of other factors such as positive energy balance, excessive intake of carbohydrates (in particular mono and disaccharides), and a sedentary lifestyle, the mechanisms to maintain a steady state of PA concentration may be disrupted leading to an over accumulation of tissue PA resulting in dyslipidemia, hyperglycemia, increased ectopic fat accumulation and increased inflammatory tone via toll-like receptor 4. It is therefore likely that the controversial data on the association of dietary PA with detrimental health effects, may be related to an excessive imbalance of dietary PA/PUFA ratio which, in certain physiopathological conditions, and in presence of an enhanced DNL, may further accelerate these deleterious effects. PMID:29167646

Integrated genomic approaches to identification of candidate genes underlying metabolic and cardiovascular phenotypes in the spontaneously hypertensive rat.

PubMed

Morrissey, Catherine; Grieve, Ian C; Heinig, Matthias; Atanur, Santosh; Petretto, Enrico; Pravenec, Michal; Hubner, Norbert; Aitman, Timothy J

2011-11-07

The spontaneously hypertensive rat (SHR) is a widely used rodent model of hypertension and metabolic syndrome. Previously we identified thousands of cis-regulated expression quantitative trait loci (eQTLs) across multiple tissues using a panel of rat recombinant inbred (RI) strains derived from Brown Norway and SHR progenitors. These cis-eQTLs represent potential susceptibility loci underlying physiological and pathophysiological traits manifested in SHR. We have prioritized 60 cis-eQTLs and confirmed differential expression between the parental strains by quantitative PCR in 43 (72%) of the eQTL transcripts. Quantitative trait transcript (QTT) analysis in the RI strains showed highly significant correlation between cis-eQTL transcript abundance and clinically relevant traits such as systolic blood pressure and blood glucose, with the physical location of a subset of the cis-eQTLs colocalizing with "physiological" QTLs (pQTLs) for these same traits. These colocalizing correlated cis-eQTLs (c3-eQTLs) are highly attractive as primary susceptibility loci for the colocalizing pQTLs. Furthermore, sequence analysis of the c3-eQTL genes identified single nucleotide polymorphisms (SNPs) that are predicted to affect transcription factor binding affinity, splicing and protein function. These SNPs, which potentially alter transcript abundance and stability, represent strong candidate factors underlying not just eQTL expression phenotypes, but also the correlated metabolic and physiological traits. In conclusion, by integration of genomic sequence, eQTL and QTT datasets we have identified several genes that are strong positional candidates for pathophysiological traits observed in the SHR strain. These findings provide a basis for the functional testing and ultimate elucidation of the molecular basis of these metabolic and cardiovascular phenotypes.

Effects of environmental pollutants on the reproduction and welfare of ruminants

PubMed Central

Rhind, S. M.; Evans, N. P.; Bellingham, M.; Sharpe, R. M.; Cotinot, C.; Mandon-Pepin, B.; Loup, B.; Sinclair, K. D.; Lea, R. G.; Pocar, P.; Fischer, B.; van der Zalm, E.; Hart, K.; Schmidt, J.-S.; Amezaga, M. R.; Fowler, P. A.

2010-01-01

Anthropogenic pollutants comprise a wide range of synthetic organic compounds and heavy metals, which are dispersed throughout the environment, usually at low concentrations. Exposure of ruminants, as for all other animals, is unavoidable and while the levels of exposure to most chemicals are usually too low to induce any physiological effects, combinations of pollutants can act additively or synergistically to perturb multiple physiological systems at all ages but particularly in the developing foetus. In sheep, organs affected by pollutant exposure include the ovary, testis, hypothalamus and pituitary gland and bone. Reported effects of exposure include changes in organ weight and gross structure, histology and gene and protein expression but these changes are not reflected in changes in reproductive performance under the conditions tested. These results illustrate the complexity of the effects of endocrine disrupting compounds on the reproductive axis, which make it difficult to extrapolate between, or even within, species. Effects of pollutant exposure on the thyroid gland, immune, cardiovascular and obesogenic systems have not been shown explicitly, in ruminants, but work on other species suggests that these systems can also be perturbed. It is concluded that exposure to a mixture of anthropogenic pollutants has significant effects on a wide variety of physiological systems, including the reproductive system. Although this physiological insult has not yet been shown to lead to a reduction in ruminant gross performance, there are already reports indicating that anthropogenic pollutant exposure can compromise several physiological systems and may pose a significant threat to both reproductive performance and welfare in the longer term. At present, many potential mechanisms of action for individual chemicals have been identified but knowledge of factors affecting the rate of tissue exposure and of the effects of combinations of chemicals on physiological systems is poor. Nevertheless, both are vital for the identification of risks to animal productivity and welfare. PMID:20582145

Regulation of bacterial virulence by Csr (Rsm) systems.

PubMed

Vakulskas, Christopher A; Potts, Anastasia H; Babitzke, Paul; Ahmer, Brian M M; Romeo, Tony

2015-06-01

Most bacterial pathogens have the remarkable ability to flourish in the external environment and in specialized host niches. This ability requires their metabolism, physiology, and virulence factors to be responsive to changes in their surroundings. It is no surprise that the underlying genetic circuitry that supports this adaptability is multilayered and exceedingly complex. Studies over the past 2 decades have established that the CsrA/RsmA proteins, global regulators of posttranscriptional gene expression, play important roles in the expression of virulence factors of numerous proteobacterial pathogens. To accomplish these tasks, CsrA binds to the 5' untranslated and/or early coding regions of mRNAs and alters translation, mRNA turnover, and/or transcript elongation. CsrA activity is regulated by noncoding small RNAs (sRNAs) that contain multiple CsrA binding sites, which permit them to sequester multiple CsrA homodimers away from mRNA targets. Environmental cues sensed by two-component signal transduction systems and other regulatory factors govern the expression of the CsrA-binding sRNAs and, ultimately, the effects of CsrA on secretion systems, surface molecules and biofilm formation, quorum sensing, motility, pigmentation, siderophore production, and phagocytic avoidance. This review presents the workings of the Csr system, the paradigm shift that it generated for understanding posttranscriptional regulation, and its roles in virulence networks of animal and plant pathogens. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Regulation of Bacterial Virulence by Csr (Rsm) Systems

PubMed Central

Vakulskas, Christopher A.; Potts, Anastasia H.; Babitzke, Paul; Ahmer, Brian M. M.

2015-01-01

SUMMARY Most bacterial pathogens have the remarkable ability to flourish in the external environment and in specialized host niches. This ability requires their metabolism, physiology, and virulence factors to be responsive to changes in their surroundings. It is no surprise that the underlying genetic circuitry that supports this adaptability is multilayered and exceedingly complex. Studies over the past 2 decades have established that the CsrA/RsmA proteins, global regulators of posttranscriptional gene expression, play important roles in the expression of virulence factors of numerous proteobacterial pathogens. To accomplish these tasks, CsrA binds to the 5′ untranslated and/or early coding regions of mRNAs and alters translation, mRNA turnover, and/or transcript elongation. CsrA activity is regulated by noncoding small RNAs (sRNAs) that contain multiple CsrA binding sites, which permit them to sequester multiple CsrA homodimers away from mRNA targets. Environmental cues sensed by two-component signal transduction systems and other regulatory factors govern the expression of the CsrA-binding sRNAs and, ultimately, the effects of CsrA on secretion systems, surface molecules and biofilm formation, quorum sensing, motility, pigmentation, siderophore production, and phagocytic avoidance. This review presents the workings of the Csr system, the paradigm shift that it generated for understanding posttranscriptional regulation, and its roles in virulence networks of animal and plant pathogens. PMID:25833324

Transcription factors involved in retinogenesis are co-opted by the circadian clock following photoreceptor differentiation

PubMed Central

Laranjeiro, Ricardo; Whitmore, David

2014-01-01

The circadian clock is known to regulate a wide range of physiological and cellular processes, yet remarkably little is known about its role during embryo development. Zebrafish offer a unique opportunity to explore this issue, not only because a great deal is known about key developmental events in this species, but also because the clock starts on the very first day of development. In this study, we identified numerous rhythmic genes in zebrafish larvae, including the key transcriptional regulators neurod and cdx1b, which are involved in neuronal and intestinal differentiation, respectively. Rhythmic expression of neurod and several additional transcription factors was only observed in the developing retina. Surprisingly, these rhythms in expression commenced at a stage of development after these transcription factors are known to have played their essential role in photoreceptor differentiation. Furthermore, this circadian regulation was maintained in adult retina. Thus, once mature photoreceptors are formed, multiple retinal transcription factors fall under circadian clock control, at which point they appear to play a new and important role in regulating rhythmic elements in the phototransduction pathway. PMID:24924194

Modulation of Food Reward by Endocrine and Environmental Factors: Update and Perspective.

PubMed

Figlewicz, Dianne P

2015-01-01

Palatable foods are frequently high in energy density. Chronic consumption of high-energy density foods can contribute to the development of cardiometabolic pathology including obesity, diabetes, and cardiovascular disease. This article reviews the contributions of extrinsic and intrinsic factors that influence the reward components of food intake. A narrative review was conducted to determine the behavioral and central nervous system (CNS) related processes involved in the reward components of high-energy density food intake. The rewarding aspects of food, particularly palatable and preferred foods, are regulated by CNS circuitry. Overlaying this regulation is modulation by intrinsic endocrine systems and metabolic hormones relating to energy homeostasis, developmental stage, or gender. It is now recognized that extrinsic or environmental factors, including ambient diet composition and the provocation of stress or anxiety, also contribute substantially to the expression of food reward behaviors such as motivation for, and seeking of, preferred foods. High-energy density food intake is influenced by both physiological and pathophysiological processes. Contextual, behavioral, and psychological factors and CNS-related processes represent potential targets for multiple types of therapeutic intervention.

Allostatic load as a predictor of all-cause and cause-specific mortality in the general population: Evidence from the Scottish Health Survey.

PubMed

Robertson, Tony; Beveridge, Gayle; Bromley, Catherine

2017-01-01

Allostatic load is a multiple biomarker measure of physiological 'wear and tear' that has shown some promise as marker of overall physiological health, but its power as a risk predictor for mortality and morbidity is less well known. This study has used data from the 2003 Scottish Health Survey (SHeS) (nationally representative sample of Scottish population) linked to mortality records to assess how well allostatic load predicts all-cause and cause-specific mortality. From the sample, data from 4,488 men and women were available with mortality status at 5 and 9.5 (rounded to 10) years after sampling in 2003. Cox proportional hazard models estimated the risk of death (all-cause and the five major causes of death in the population) according to allostatic load score. Multiple imputation was used to address missing values in the dataset. Analyses were also adjusted for potential confounders (sex, age and deprivation). There were 258 and 618 deaths over the 5-year and 10-year follow-up period, respectively. In the fully-adjusted model, higher allostatic load (poorer physiological 'health') was not associated with an increased risk of all-cause mortality after 5 years (HR = 1.07, 95% CI 0.94 to 1.22; p = 0.269), but it was after 10 years (HR = 1.08, 95% CI 1.01 to 1.16; p = 0.026). Allostatic load was not associated with specific causes of death over the same follow-up period. In conclusions, greater physiological wear and tear across multiple physiological systems, as measured by allostatic load, is associated with an increased risk of death, but may not be as useful as a predictor for specific causes of death.

Allostatic load as a predictor of all-cause and cause-specific mortality in the general population: Evidence from the Scottish Health Survey

PubMed Central

Beveridge, Gayle; Bromley, Catherine

2017-01-01

Allostatic load is a multiple biomarker measure of physiological ‘wear and tear’ that has shown some promise as marker of overall physiological health, but its power as a risk predictor for mortality and morbidity is less well known. This study has used data from the 2003 Scottish Health Survey (SHeS) (nationally representative sample of Scottish population) linked to mortality records to assess how well allostatic load predicts all-cause and cause-specific mortality. From the sample, data from 4,488 men and women were available with mortality status at 5 and 9.5 (rounded to 10) years after sampling in 2003. Cox proportional hazard models estimated the risk of death (all-cause and the five major causes of death in the population) according to allostatic load score. Multiple imputation was used to address missing values in the dataset. Analyses were also adjusted for potential confounders (sex, age and deprivation). There were 258 and 618 deaths over the 5-year and 10-year follow-up period, respectively. In the fully-adjusted model, higher allostatic load (poorer physiological ‘health’) was not associated with an increased risk of all-cause mortality after 5 years (HR = 1.07, 95% CI 0.94 to 1.22; p = 0.269), but it was after 10 years (HR = 1.08, 95% CI 1.01 to 1.16; p = 0.026). Allostatic load was not associated with specific causes of death over the same follow-up period. In conclusions, greater physiological wear and tear across multiple physiological systems, as measured by allostatic load, is associated with an increased risk of death, but may not be as useful as a predictor for specific causes of death. PMID:28813505

Predictors of nursing workload in elderly patients admitted to intensive care units.

PubMed

Sousa, Cleber Ricardo de; Gonçalves, Leilane Andrade; Toffoleto, Maria Cecília; Leão, Karine; Padilha, Kátia Grillo

2008-01-01

The age of patients is a controversial issue in admission to intensive care unit (ICU). The aim of this study was to compare severity and nursing workload of elderly patients with 60-69, 70-79, and e"80 years of age and to identify predictors of nursing workload in elderly patients. A cross sectional study was performed with a sample of 71 elderly patients admitted to three ICU in the city of Sao Paulo, Brazil from October to November 2004. Data were prospectively collected using Nursing Activities Score (NAS) and Simplified Acute Physiology Score II (SAPS II). There was no significant difference in nursing workload among the elderly patients age subgroups (p=0.84). Multiple regression analysis indicated that the independent risk factors of high nursing workload were severity, age e"70 years, and to be a surgical ICU patient. Age as an isolated factor should not be discriminative for elderly patients admission to ICU.

Factors and pathways involved in capacitation: how are they regulated?

PubMed Central

Jin, Shi-Kai; Yang, Wan-Xi

2017-01-01

In mammals, fertilization occurs via a comprehensive progression of events. Freshly ejaculated sperm have yet to acquire progressive motility or fertilization ability. They must first undergo a series of biochemical and physiological changes, collectively known as capacitation. Capacitation is a significant prerequisite to fertilization. During the process of capacitation, changes in membrane properties, intracellular ion concentration and the activities of enzymes, together with other protein modifications, induce multiple signaling events and pathways in defined media in vitro or in the female reproductive tract in vivo. These, in turn, stimulate the acrosome reaction and prepare spermatozoa for penetration of the egg zona pellucida prior to fertilization. In the present review, we conclude all mainstream factors and pathways regulate capacitation and highlight their crosstalk. We also summarize the relationship between capacitation and assisted reproductive technology or human disease. In the end, we sum up the open questions and future avenues in this field. PMID:27690295

Vesiculation from Pseudomonas aeruginosa under SOS.

PubMed

Maredia, Reshma; Devineni, Navya; Lentz, Peter; Dallo, Shatha F; Yu, Jiehjuen; Guentzel, Neal; Chambers, James; Arulanandam, Bernard; Haskins, William E; Weitao, Tao

2012-01-01

Bacterial infections can be aggravated by antibiotic treatment that induces SOS response and vesiculation. This leads to a hypothesis concerning association of SOS with vesiculation. To test it, we conducted multiple analyses of outer membrane vesicles (OMVs) produced from the Pseudomonas aeruginosa wild type in which SOS is induced by ciprofloxacin and from the LexA noncleavable (lexAN) strain in which SOS is repressed. The levels of OMV proteins, lipids, and cytotoxicity increased for both the treated strains, demonstrating vesiculation stimulation by the antibiotic treatment. However, the further increase was suppressed in the lexAN strains, suggesting the SOS involvement. Obviously, the stimulated vesiculation is attributed by both SOS-related and unrelated factors. OMV subproteomic analysis was performed to examine these factors, which reflected the OMV-mediated cytotoxicity and the physiology of the vesiculating cells under treatment and SOS. Thus, SOS plays a role in the vesiculation stimulation that contributes to cytotoxicity.

Vesiculation from Pseudomonas aeruginosa under SOS

PubMed Central

Maredia, Reshma; Devineni, Navya; Lentz, Peter; Dallo, Shatha F.; Yu, JiehJuen; Guentzel, Neal; Chambers, James; Arulanandam, Bernard; Haskins, William E.; Weitao, Tao

2012-01-01

Bacterial infections can be aggravated by antibiotic treatment that induces SOS response and vesiculation. This leads to a hypothesis concerning association of SOS with vesiculation. To test it, we conducted multiple analyses of outer membrane vesicles (OMVs) produced from the Pseudomonas aeruginosa wild type in which SOS is induced by ciprofloxacin and from the LexA noncleavable (lexAN) strain in which SOS is repressed. The levels of OMV proteins, lipids, and cytotoxicity increased for both the treated strains, demonstrating vesiculation stimulation by the antibiotic treatment. However, the further increase was suppressed in the lexAN strains, suggesting the SOS involvement. Obviously, the stimulated vesiculation is attributed by both SOS-related and unrelated factors. OMV subproteomic analysis was performed to examine these factors, which reflected the OMV-mediated cytotoxicity and the physiology of the vesiculating cells under treatment and SOS. Thus, SOS plays a role in the vesiculation stimulation that contributes to cytotoxicity. PMID:22448133

Coordinated regulation of photosynthesis in rice increases yield and tolerance to environmental stress

PubMed Central

Ambavaram, Madana M. R.; Basu, Supratim; Krishnan, Arjun; Ramegowda, Venkategowda; Batlang, Utlwang; Rahman, Lutfor; Baisakh, Niranjan; Pereira, Andy

2014-01-01

Plants capture solar energy and atmospheric carbon dioxide (CO2) through photosynthesis, which is the primary component of crop yield, and needs to be increased considerably to meet the growing global demand for food. Environmental stresses, which are increasing with climate change, adversely affect photosynthetic carbon metabolism (PCM) and limit yield of cereals such as rice (Oryza sativa) that feeds half the world. To study the regulation of photosynthesis, we developed a rice gene regulatory network and identified a transcription factor HYR (HIGHER YIELD RICE) associated with PCM, which on expression in rice enhances photosynthesis under multiple environmental conditions, determining a morpho-physiological programme leading to higher grain yield under normal, drought and high-temperature stress conditions. We show HYR is a master regulator, directly activating photosynthesis genes, cascades of transcription factors and other downstream genes involved in PCM and yield stability under drought and high-temperature environmental stress conditions. PMID:25358745

Measurement of lung volumes from supine portable chest radiographs.

PubMed

Ries, A L; Clausen, J L; Friedman, P J

1979-12-01

Lung volumes in supine nonambulatory patients are physiological parameters often difficult to measure with current techniques (plethysmograph, gas dilution). Existing radiographic methods for measuring lung volumes require standard upright chest radiographs. Accordingly, in 31 normal supine adults, we determined helium-dilution functional residual and total lung capacities and measured planimetric lung field areas (LFA) from corresponding portable anteroposterior and lateral radiographs. Low radiation dose methods, which delivered less than 10% of that from standard portable X-ray technique, were utilized. Correlation between lung volume and radiographic LFA was highly significant (r = 0.96, SEE = 10.6%). Multiple-step regressions using height and chest diameter correction factors reduced variance, but weight and radiographic magnification factors did not. In 17 additional subjects studied for validation, the regression equations accurately predicted radiographic lung volume. Thus, this technique can provide accurate and rapid measurement of lung volume in studies involving supine patients.

From cognition to the system: developing a multilevel taxonomy of patient safety in general practice.

PubMed

Kostopoulou, O

The paper describes the process of developing a taxonomy of patient safety in general practice. The methodologies employed included fieldwork, task analysis and confidential reporting of patient-safety events in five West Midlands practices. Reported events were traced back to their root causes and contributing factors. The resulting taxonomy is based on a theoretical model of human cognition, includes multiple levels of classification to reflect the chain of causation and considers affective and physiological influences on performance. Events are classified at three levels. At level one, the information-processing model of cognition is used to classify errors. At level two, immediate causes are identified, internal and external to the individual. At level three, more remote causal factors are classified as either 'work organization' or 'technical' with subcategories. The properties of the taxonomy (validity, reliability, comprehensiveness) as well as its usability and acceptability remain to be tested with potential users.

Consequences of not treating children with laron syndrome (primary growth hormone insensitivity).

PubMed

Laron, Z

2001-01-01

The follow-up of a large cohort of patients with Laron syndrome (LS) from infancy to adult age has enabled us to determine the effects of long-term insulin-like growth factor-I (IGF-I) deficiency on auxological, biochemical, physiological and psychological parameters. We found that early and continuous IGF-I deficiency (the anabolic effector of growth hormone) causes dwarfism, acromicria, organomicria, marked obesity, insulin resistance, retardation of skeletal maturation and osteoporosis, as well as muscular and central nervous tissue underdevelopment, and a series of biochemical changes including hypercholesterolemia. These multiple pathologies impair the quality of life of these patients. It is concluded that patients with LS need IGF-I replacement treatment throughout life.

Nanotechnology use with cosmeceuticals.

PubMed

Golubovic-Liakopoulos, Nevenka; Simon, Sanford R; Shah, Bhavdeep

2011-09-01

The skin is a complex organ and its aging is a complex process. Cutaneous aging is influenced by factors such as sun exposure, genetics, stress and the environment. While skin laxity, rhytides, and dyschromia appear on the surface, these processes originate in deeper layers including the dermis and subcutaneous tissues. Until recently, most topical skin treatments were applied to, and consequently only affected the skin surface. Skin care has evolved to be scientifically based, and as knowledge increases about the physiology of the skin, novel methods of maintaining its health and appearance are developed. New generation skin care products are targeting multiple aging mechanisms by utilizing functional active ingredients in combination with innovative delivery systems. Copyright © 2011 Elsevier Inc. All rights reserved.

Redefining the gut as the motor of critical illness.

PubMed

Mittal, Rohit; Coopersmith, Craig M

2014-04-01

The gut is hypothesized to play a central role in the progression of sepsis and multiple organ dysfunction syndrome. Critical illness alters gut integrity by increasing epithelial apoptosis and permeability and by decreasing epithelial proliferation and mucus integrity. Additionally, toxic gut-derived lymph induces distant organ injury. Although the endogenous microflora ordinarily exist in a symbiotic relationship with the gut epithelium, severe physiological insults alter this relationship, leading to induction of virulence factors in the microbiome, which, in turn, can perpetuate or worsen critical illness. This review highlights newly discovered ways in which the gut acts as the motor that perpetuates the systemic inflammatory response in critical illness. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantifying and modeling long-range cross correlations in multiple time series with applications to world stock indices

NASA Astrophysics Data System (ADS)

Wang, Duan; Podobnik, Boris; Horvatić, Davor; Stanley, H. Eugene

2011-04-01

We propose a modified time lag random matrix theory in order to study time-lag cross correlations in multiple time series. We apply the method to 48 world indices, one for each of 48 different countries. We find long-range power-law cross correlations in the absolute values of returns that quantify risk, and find that they decay much more slowly than cross correlations between the returns. The magnitude of the cross correlations constitutes “bad news” for international investment managers who may believe that risk is reduced by diversifying across countries. We find that when a market shock is transmitted around the world, the risk decays very slowly. We explain these time-lag cross correlations by introducing a global factor model (GFM) in which all index returns fluctuate in response to a single global factor. For each pair of individual time series of returns, the cross correlations between returns (or magnitudes) can be modeled with the autocorrelations of the global factor returns (or magnitudes). We estimate the global factor using principal component analysis, which minimizes the variance of the residuals after removing the global trend. Using random matrix theory, a significant fraction of the world index cross correlations can be explained by the global factor, which supports the utility of the GFM. We demonstrate applications of the GFM in forecasting risks at the world level, and in finding uncorrelated individual indices. We find ten indices that are practically uncorrelated with the global factor and with the remainder of the world indices, which is relevant information for world managers in reducing their portfolio risk. Finally, we argue that this general method can be applied to a wide range of phenomena in which time series are measured, ranging from seismology and physiology to atmospheric geophysics.

Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: focus on the cancer hallmark of tumor angiogenesis.

PubMed

Hu, Zhiwei; Brooks, Samira A; Dormoy, Valérian; Hsu, Chia-Wen; Hsu, Hsue-Yin; Lin, Liang-Tzung; Massfelder, Thierry; Rathmell, W Kimryn; Xia, Menghang; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Brown, Dustin G; Prudhomme, Kalan R; Colacci, Annamaria; Hamid, Roslida A; Mondello, Chiara; Raju, Jayadev; Ryan, Elizabeth P; Woodrick, Jordan; Scovassi, A Ivana; Singh, Neetu; Vaccari, Monica; Roy, Rabindra; Forte, Stefano; Memeo, Lorenzo; Salem, Hosni K; Lowe, Leroy; Jensen, Lasse; Bisson, William H; Kleinstreuer, Nicole

2015-06-01

One of the important 'hallmarks' of cancer is angiogenesis, which is the process of formation of new blood vessels that are necessary for tumor expansion, invasion and metastasis. Under normal physiological conditions, angiogenesis is well balanced and controlled by endogenous proangiogenic factors and antiangiogenic factors. However, factors produced by cancer cells, cancer stem cells and other cell types in the tumor stroma can disrupt the balance so that the tumor microenvironment favors tumor angiogenesis. These factors include vascular endothelial growth factor, endothelial tissue factor and other membrane bound receptors that mediate multiple intracellular signaling pathways that contribute to tumor angiogenesis. Though environmental exposures to certain chemicals have been found to initiate and promote tumor development, the role of these exposures (particularly to low doses of multiple substances), is largely unknown in relation to tumor angiogenesis. This review summarizes the evidence of the role of environmental chemical bioactivity and exposure in tumor angiogenesis and carcinogenesis. We identify a number of ubiquitous (prototypical) chemicals with disruptive potential that may warrant further investigation given their selectivity for high-throughput screening assay targets associated with proangiogenic pathways. We also consider the cross-hallmark relationships of a number of important angiogenic pathway targets with other cancer hallmarks and we make recommendations for future research. Understanding of the role of low-dose exposure of chemicals with disruptive potential could help us refine our approach to cancer risk assessment, and may ultimately aid in preventing cancer by reducing or eliminating exposures to synergistic mixtures of chemicals with carcinogenic potential. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Quantifying and modeling long-range cross correlations in multiple time series with applications to world stock indices.

PubMed

Wang, Duan; Podobnik, Boris; Horvatić, Davor; Stanley, H Eugene

2011-04-01

We propose a modified time lag random matrix theory in order to study time-lag cross correlations in multiple time series. We apply the method to 48 world indices, one for each of 48 different countries. We find long-range power-law cross correlations in the absolute values of returns that quantify risk, and find that they decay much more slowly than cross correlations between the returns. The magnitude of the cross correlations constitutes "bad news" for international investment managers who may believe that risk is reduced by diversifying across countries. We find that when a market shock is transmitted around the world, the risk decays very slowly. We explain these time-lag cross correlations by introducing a global factor model (GFM) in which all index returns fluctuate in response to a single global factor. For each pair of individual time series of returns, the cross correlations between returns (or magnitudes) can be modeled with the autocorrelations of the global factor returns (or magnitudes). We estimate the global factor using principal component analysis, which minimizes the variance of the residuals after removing the global trend. Using random matrix theory, a significant fraction of the world index cross correlations can be explained by the global factor, which supports the utility of the GFM. We demonstrate applications of the GFM in forecasting risks at the world level, and in finding uncorrelated individual indices. We find ten indices that are practically uncorrelated with the global factor and with the remainder of the world indices, which is relevant information for world managers in reducing their portfolio risk. Finally, we argue that this general method can be applied to a wide range of phenomena in which time series are measured, ranging from seismology and physiology to atmospheric geophysics.

Application of a Utility Analysis to Evaluate a Novel Assessment Tool for Clinically Oriented Physiology and Pharmacology

ERIC Educational Resources Information Center

Cramer, Nicholas; Asmar, Abdo; Gorman, Laurel; Gros, Bernard; Harris, David; Howard, Thomas; Hussain, Mujtaba; Salazar, Sergio; Kibble, Jonathan D.

2016-01-01

Multiple-choice questions are a gold-standard tool in medical school for assessment of knowledge and are the mainstay of licensing examinations. However, multiple-choice questions items can be criticized for lacking the ability to test higher-order learning or integrative thinking across multiple disciplines. Our objective was to develop a novel…

Myelin damage and repair in pathologic CNS: challenges and prospects

PubMed Central

Alizadeh, Arsalan; Dyck, Scott M.; Karimi-Abdolrezaee, Soheila

2015-01-01

Injury to the central nervous system (CNS) results in oligodendrocyte cell death and progressive demyelination. Demyelinated axons undergo considerable physiological changes and molecular reorganizations that collectively result in axonal dysfunction, degeneration and loss of sensory and motor functions. Endogenous adult oligodendrocyte precursor cells and neural stem/progenitor cells contribute to the replacement of oligodendrocytes, however, the extent and quality of endogenous remyelination is suboptimal. Emerging evidence indicates that optimal remyelination is restricted by multiple factors including (i) low levels of factors that promote oligodendrogenesis; (ii) cell death among newly generated oligodendrocytes, (iii) inhibitory factors in the post-injury milieu that impede remyelination, and (iv) deficient expression of key growth factors essential for proper re-construction of a highly organized myelin sheath. Considering these challenges, over the past several years, a number of cell-based strategies have been developed to optimize remyelination therapeutically. Outcomes of these basic and preclinical discoveries are promising and signify the importance of remyelination as a mechanism for improving functions in CNS injuries. In this review, we provide an overview on: (1) the precise organization of myelinated axons and the reciprocal axo-myelin interactions that warrant properly balanced physiological activities within the CNS; (2) underlying cause of demyelination and the structural and functional consequences of demyelination in axons following injury and disease; (3) the endogenous mechanisms of oligodendrocyte replacement; (4) the modulatory role of reactive astrocytes and inflammatory cells in remyelination; and (5) the current status of cell-based therapies for promoting remyelination. Careful elucidation of the cellular and molecular mechanisms of demyelination in the pathologic CNS is a key to better understanding the impact of remyelination for CNS repair. PMID:26283909

Indicators of Multiple Personality Disorder for the Clinician.

ERIC Educational Resources Information Center

Dalton, Thomas W.

Multiple personality disorder (MPD) is now recognized as a valid diagnostic category. Occurrence may be higher than previously suspected. While physiological testing of MPD has shown significant differences between the various personalities of individuals in terms of galvanic skin response, electroencephalogram recordings, electrodermal response…

Childhood poverty and health: cumulative risk exposure and stress dysregulation.

PubMed

Evans, Gary W; Kim, Pilyoung

2007-11-01

A massive literature documents the inverse association between poverty or low socioeconomic status and health, but little is known about the mechanisms underlying this robust relation. We examined longitudinal relations between duration of poverty exposure since birth, cumulative risk exposure, and physiological stress in two hundred seven 13-year-olds. Chronic stress was assessed by basal blood pressure and overnight cortisol levels; stress regulation was assessed by cardiovascular reactivity to a standard acute stressor and recovery after exposure to this stressor. Cumulative risk exposure was measured by multiple physical (e.g., substandard housing) and social (e.g., family turmoil) risk factors. The greater the number of years spent living in poverty, the more elevated was overnight cortisol and the more dysregulated was the cardiovascular response (i.e., muted reactivity). Cardiovascular recovery was not affected by duration of poverty exposure. Unlike the duration of poverty exposure, concurrent poverty (i.e., during adolescence) did not affect these physiological stress outcomes. The effects of childhood poverty on stress dysregulation are largely explained by cumulative risk exposure accompanying childhood poverty.

Signaling, physiological functions and clinical relevance of the G protein-coupled estrogen receptor GPER.

PubMed

Prossnitz, Eric R; Barton, Matthias

2009-09-01

GPR30, now named GPER1 (G protein-coupled estrogen receptor1) or GPER here, was first identified as an orphan 7-transmembrane G protein-coupled receptor by multiple laboratories using either homology cloning or differential expression and subsequently shown to be required for estrogen-mediated signaling in certain cancer cells. The actions of estrogen are extensive in the body and are thought to be mediated predominantly by classical nuclear estrogen receptors that act as transcription factors/regulators. Nevertheless, certain aspects of estrogen function remain incompatible with the generally accepted mechanisms of classical estrogen receptor action. Many recent studies have revealed that GPER contributes to some of the actions of estrogen, including rapid signaling events and rapid transcriptional activation. With the introduction of GPER-selective ligands and GPER knockout mice, the functions of GPER are becoming more clearly defined. In many cases, there appears to be a complex interplay between the two receptor systems, suggesting that estrogen-mediated physiological responses may be mediated by either receptor or a combination of both receptor types, with important medical implications.

Correlation between vortices and wall shear stress in a curved artery model under pulsatile flow conditions

NASA Astrophysics Data System (ADS)

Cox, Christopher; Plesniak, Michael W.

2017-11-01

One of the most physiologically relevant factors within the cardiovascular system is the wall shear stress. The wall shear stress affects endothelial cells via mechanotransduction and atherosclerotic regions are strongly correlated with curvature and branching in the human vasculature, where the shear stress is both oscillatory and multidirectional. Also, the combined effect of curvature and pulsatility in cardiovascular flows produces unsteady vortices. In this work, our goal is to assess the correlation between multiple vortex pairs and wall shear stress. To accomplish this, we use an in-house high-order flux reconstruction Navier-Stokes solver to simulate pulsatile flow of a Newtonian blood-analog fluid through a rigid 180° curved artery model. We use a physiologically relevant flow rate and generate results using both fully developed and uniform entrance conditions, the latter motivated by the fact that flow upstream to a curved artery may not be fully developed. Under these two inflow conditions, we characterize the evolution of various vortex pairs and their subsequent effect on several wall shear stress metrics. Supported by GW Center for Biomimetics and Bioinspired Engineering.

A comparative evaluation of adaptive noise cancellation algorithms for minimizing motion artifacts in a forehead-mounted wearable pulse oximeter.

PubMed

Comtois, Gary; Mendelson, Yitzhak; Ramuka, Piyush

2007-01-01

Wearable physiological monitoring using a pulse oximeter would enable field medics to monitor multiple injuries simultaneously, thereby prioritizing medical intervention when resources are limited. However, a primary factor limiting the accuracy of pulse oximetry is poor signal-to-noise ratio since photoplethysmographic (PPG) signals, from which arterial oxygen saturation (SpO2) and heart rate (HR) measurements are derived, are compromised by movement artifacts. This study was undertaken to quantify SpO2 and HR errors induced by certain motion artifacts utilizing accelerometry-based adaptive noise cancellation (ANC). Since the fingers are generally more vulnerable to motion artifacts, measurements were performed using a custom forehead-mounted wearable pulse oximeter developed for real-time remote physiological monitoring and triage applications. This study revealed that processing motion-corrupted PPG signals by least mean squares (LMS) and recursive least squares (RLS) algorithms can be effective to reduce SpO2 and HR errors during jogging, but the degree of improvement depends on filter order. Although both algorithms produced similar improvements, implementing the adaptive LMS algorithm is advantageous since it requires significantly less operations.

Basketball Performance Is Related to Maturity and Relative Age in Elite Adolescent Players.

PubMed

Torres-Unda, Jon; Zarrazquin, Idoia; Gravina, Leyre; Zubero, Jaime; Seco, Jesús; Gil, Susana M; Gil, Javier; Irazusta, Jon

2016-05-01

During a national championship, the anthropometric, physiological, and maturation characteristics of 13- to 14-year-old players of elite basketball teams and their association with sport performance were analyzed. Body parameters (weight, height, skinfold thicknesses, and lengths) were measured and physiological capacities assessed by sprint (20 m) and jump tests (i.e., countermovement jump with arm swing). Chronological age (CA) and maturity offset (years from age at peak height velocity; YAPHV) were calculated, and then predicted age at peak height velocity, as the difference between CA and YAPHV. Game performance was assessed with point averages and the performance index rating (PIR). The birth-date distribution of players was biased, those born early in the selection year outnumbering those born later. Anthropometric analysis indicated that players who performed better had longer body lengths. Physiological testing showed that semi-finalists had better sprint performance than quarter-finalists and those players with greater jump capacity scored more points. Early maturation and advanced maturity status were also associated with better PIR and scored points per game. Multiple blockwise regression analysis showed that, among the factors analyzed, YAPHV was the best predictor of basketball performance. In conclusion, around puberty, physical and physiological parameters associated with maturity and CA are important in determining the success of elite basketball players. Consequently, boys who are born in the second half of the year and/or late maturing tend to be marginalized or totally excluded, and not given the chance to play under equal conditions; their careers may then be held back by the relative disadvantage associated with inexperience.

Early life stress increases testosterone and corticosterone and alters stress physiology in zebra finches.

PubMed

Zito, J Bayley; Hanna, Angy; Kadoo, Nora; Tomaszycki, Michelle L

2017-09-01

Early life stress has enduring effects on behavior and physiology. However, the effects on hormones and stress physiology remain poorly understood. In the present study, parents of zebra finches of both sexes were exposed to an increased foraging paradigm from 3 to 33days post hatching. Plasma and brains were collected from chicks at 3 developmental time points: post hatching days 25, 60 and adulthood. Plasma was assayed for testosterone (T), estradiol (E2), and corticosterone (CORT). The paraventricular nucleus of the hypothalamus was assessed for corticotrophin releasing factor (CRH) and glucocorticoid receptor (GR) expression. As expected, body mass was lower in nutritionally stressed animals compared to controls at multiple ages. Nutritionally stressed animals overall had higher levels of CORT than did control and this was particularly apparent in females at post hatching day 25. Nutritionally stressed animals also had a higher number of cells expressing CRH and GR in the paraventricular nucleus of the hypothalamus than did controls. There was an interaction, such that both measures were higher in control animals at PHD 25, but higher in NS animals by adulthood. Females, regardless of treatment, had higher circulating CORT and a higher number of cells expressing CRH than did males. Nutritionally stressed animals also had higher levels of T than did control animals, and this difference was greatest for males at post hatching day 60. There were no effects of nutritional stress on E2. These findings suggest that nutritional stress during development has long-lasting effects on testosterone and stress physiology. Copyright © 2017 Elsevier Inc. All rights reserved.

A general enhancement of autonomic and cortisol responses during social evaluative threat

PubMed Central

Bosch, Jos A.; de Geus, Eco J.C.; Carroll, Douglas; Goedhart, Annebet D.; Anane, Leila A.; van Zanten, Jet J Veldhuizen; Helmerhorst, Eva J.; Edwards, Kate M.

2013-01-01

Objective The idea that distinct psychosocial factors may underlie specific patterns of neuroendocrine stress responses has been a topic of recurrent debate. We examined a recent contribution to this debate, the Social Self Preservation Theory, which predicts that stressors involving social evaluative threat (SET) characteristically activate the hypothalamic-pituitary-adrenal (HPA) axis. Methods Sixty-one healthy university students (31 females) performed a challenging speech task in one of three conditions that aimed to impose increasing levels of SET: performing the task alone (no social evaluation), with 1 evaluating observer, or with 4 evaluating observers. Indices of sympathetic (pre-ejection period) and parasympathetic (heart rate variability) cardiac drive were obtained by impedance- and electrocardiography. Salivary cortisol was used to index HPA activity. Questionnaires assessed affective responses. Results Affective responses (shame/embarrassment, anxiety, negative affect, and self-esteem), cortisol, heart rate, sympathetic, and parasympathetic activation all differentiated evaluative from non-evaluative task conditions (p<.001). The largest effect-sizes were observed for cardiac autonomic responses. Physiological reactivity increased in parallel with increasing audience size (p<.001). A rise in cortisol was predicted by sympathetic activation during the task (p<.001), but not by affective responses. Conclusion It would appear that SET determines the magnitude, rather than the pattern, of physiological activation. This potential to broadly perturb multiple physiological systems may help explain why social stress has been associated with a range of health outcomes. We propose a threshold-activation model as a physiological explanation for why engaging stressors, such as those involving social evaluation or uncontrollability, may appear to selectively induce cortisol release. PMID:19779143

Breath-Hold Diving.

PubMed

Fitz-Clarke, John R

2018-03-25

Breath-hold diving is practiced by recreational divers, seafood divers, military divers, and competitive athletes. It involves highly integrated physiology and extreme responses. This article reviews human breath-hold diving physiology beginning with an historical overview followed by a summary of foundational research and a survey of some contemporary issues. Immersion and cardiovascular adjustments promote a blood shift into the heart and chest vasculature. Autonomic responses include diving bradycardia, peripheral vasoconstriction, and splenic contraction, which help conserve oxygen. Competitive divers use a technique of lung hyperinflation that raises initial volume and airway pressure to facilitate longer apnea times and greater depths. Gas compression at depth leads to sequential alveolar collapse. Airway pressure decreases with depth and becomes negative relative to ambient due to limited chest compliance at low lung volumes, raising the risk of pulmonary injury called "squeeze," characterized by postdive coughing, wheezing, and hemoptysis. Hypoxia and hypercapnia influence the terminal breakpoint beyond which voluntary apnea cannot be sustained. Ascent blackout due to hypoxia is a danger during long breath-holds, and has become common amongst high-level competitors who can suppress their urge to breathe. Decompression sickness due to nitrogen accumulation causing bubble formation can occur after multiple repetitive dives, or after single deep dives during depth record attempts. Humans experience responses similar to those seen in diving mammals, but to a lesser degree. The deepest sled-assisted breath-hold dive was to 214 m. Factors that might determine ultimate human depth capabilities are discussed. © 2018 American Physiological Society. Compr Physiol 8:585-630, 2018. Copyright © 2018 American Physiological Society. All rights reserved.

A Review of Cardiac Autonomic Measures: Considerations for Examination of Physiological Response in Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Benevides, Teal W.; Lane, Shelly J.

2015-01-01

The autonomic nervous system (ANS) is responsible for multiple physiological responses, and dysfunction of this system is often hypothesized as contributing to cognitive, affective, and behavioral responses in children. Research suggests that examination of ANS activity may provide insight into behavioral dysregulation in children with autism…

Melatonin, The Pineal Gland and Circadian Rhythms

DTIC Science & Technology

1992-04-30

physiological rhythms including locomotion, sleep/wake, thermoregulation , car- diovascular function and many endocrine processes. Among the rhythms under SCN...control of a wide array of behavioral and physiological rhythms including locomotion, sleep/wake, thermoregulation , cardiovascular function and many... reptiles and birds, overt rhythmicity results from the integration of multiple circadian oscillators within the pineal gland, eyes and the presumed

Upgrading well plates using open microfluidic patterning.

PubMed

Berry, Samuel B; Zhang, Tianzi; Day, John H; Su, Xiaojing; Wilson, Ilham Z; Berthier, Erwin; Theberge, Ashleigh B

2017-12-05

Cellular communication between multiple cell types is a ubiquitous process that is responsible for vital physiological responses observed in vivo (e.g., immune response, organ function). Many in vitro coculture strategies have been developed, both in traditional culture and microscale systems, and have shown the potential to recreate some of the physiological behaviors of organs or groups of cells. A fundamental limitation of current systems is the difficulty of reconciling the additional engineering requirements for creating soluble factor signaling systems (e.g., segregated cell culture) with the use of well-characterized materials and platforms that have demonstrated successful results and biocompatibility in assays. We present a new open-microfluidic platform, the Monorail Device, that is placed in any existing well plate or Petri dish and enables patterning of segregated coculture regions, thereby allowing the direct upgrade of monoculture experiments into multiculture assays. Our platform patterns biocompatible hydrogel walls via microfluidic spontaneous capillary flow (SCF) along a rail insert set inside commercially available cultureware, creating customized pipette-accessible cell culture chambers that require fewer cells than standard macroscale culture. Importantly, the device allows the use of native surfaces without additional modification or treatments, while creating permeable dividers for the diffusion of soluble factors. Additionally, the ease of patterning afforded by our platform makes reconfiguration of the culture region as simple as changing the rail insert. We demonstrate the ability of the device to pattern flows on a variety of cell culture surfaces and create hydrogel walls in complex and precise shapes. We characterize the physical parameters that enable a reproducible SCF-driven flow and highlight specialized design features that increase the ease of use of the device and control of the open microfluidic flow. Further, we present the performance of our platform according to useful coculture criteria, including permeability and integrity of our hydrogel walls and surface-sensitive cell culture. Lastly, we show the potential of this type of platform to create modular multikingdom culture systems that can be used to study soluble factor signaling between mammalian cells, bacteria, and fungi, as well as the potential for adaptation of this technology by researchers across multiple fields.

Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer—Part 1

PubMed Central

Sagar, S.M.; Yance, D.; Wong, R.K.

2006-01-01

An integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of these agents that can inhibit tumour progression and reduce the risk of metastasis. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclooxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. The herbs that are traditionally used for anticancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose–response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as adaptogens, potentially enhancing the efficacy of the conventional therapies. PMID:17576437

Early Socioeconomic Adversity and Young Adult Physical Illness: The Role of Body Mass Index and Depressive Symptoms

PubMed Central

Wickrama, K. A. S.; Kwon, Josephine A.; Oshri, Assaf; Lee, Tae Kyoung

2014-01-01

Purpose The present study investigated the psycho-physiological inter and intra-individual processes that mediate the linkage between childhood/adolescent socioeconomic adversities and adult health outcomes. Specifically, the proposed model examined the roles of youth depressive symptoms and BMI trajectories as mediators that explain the link between early adversity and young adults’ general health and physical illnesses after controlling for gender, race/ethnicity, and earlier general health reports. Methods Using a nationally representative sample of 12,424 from National Longitudinal Study of Adolescent Health (Add Health), this study used growth curve modeling to consider both the severity (initial level) as well as the change over time (deterioration or elevation) as psycho-physiological mediators, thereby acknowledging multiple facets of depressive symptoms and BMI trajectories as psych-physiological mediators of early adversity to adult health. Results Results provide evidence for (a) the influence of early childhood and early adolescent cumulative socioeconomic adversity on both the initial levels and changes over time of depressive symptoms and BMI and (b) the independent influences depressive symptoms and BMI trajectories on the general health and the physical illnesses of young adults Conclusions These findings contribute valuable knowledge to existing research by elucidating how early adversity exerts an enduring long-term influence on physical health problems in young adulthood; further, this information suggests effective intervention and prevention programs should incorporate multiple facets (severity and change over time) of multiple mechanisms (psychological and physiological). PMID:24856408

Abnormal aldosterone physiology and cardiometabolic risk factors.

PubMed

Vaidya, Anand; Underwood, Patricia C; Hopkins, Paul N; Jeunemaitre, Xavier; Ferri, Claudio; Williams, Gordon H; Adler, Gail K

2013-04-01

Abnormal aldosterone physiology has been implicated in the pathogenesis of cardiometabolic diseases. Single aldosterone measurements capture only a limited range of aldosterone physiology. New methods of characterizing aldosterone physiology may provide a more comprehensive understanding of its relationship with cardiometabolic disease. We evaluated whether novel indices of aldosterone responses to dietary sodium modulation, the sodium-modulated aldosterone suppression-stimulation index (SASSI for serum and SAUSSI for urine), could predict cardiometabolic risk factors. We performed cross-sectional analyses on 539 subjects studied on liberal and restricted sodium diets with serum and urinary aldosterone measurements. SASSI and SAUSSI were calculated as the ratio of aldosterone on liberal (maximally suppressed aldosterone) to the aldosterone on restricted (stimulated aldosterone) diets and associated with risk factors using adjusted regression models. Cardiometabolic risk factors associated with either impaired suppression of aldosterone on liberal diet, or impaired stimulation on restricted diet, or both; in all of these individual cases, these risk factors associated with higher SASSI or SAUSSI. In the context of abnormalities that constitute the metabolic syndrome, there was a strong positive association between the number of metabolic syndrome components (0-4) and both SASSI and SAUSSI (P<0.0001) that was independent of known aldosterone secretagogues (angiotensin II, corticotropin, potassium). SASSI and SAUSSI exhibited a high sensitivity in detecting normal individuals with zero metabolic syndrome components (86% for SASSI and 83% for SAUSSI). Assessing the physiological range of aldosterone responses may provide greater insights into adrenal pathophysiology. Dysregulated aldosterone physiology may contribute to, or result from, early cardiometabolic abnormalities.

Aristotle score predicts outcome in patients requiring extracorporeal circulatory support following repair of congenital heart disease.

PubMed

Derby, Christopher D; Kolcz, Jacek; Kerins, Paul J; Duncan, Daniel R; Quezada, Emilio; Pizarro, Christian

2007-01-01

Extracorporeal membrane oxygenation (ECMO) has become the standard technique of mechanical support for the failing circulation following repair of congenital heart lesions. The objective of this study was to identify predictors of survival in patients requiring postcardiotomy ECMO. The Aristotle score, a method developed to evaluate quality of care based on complexity, was investigated as a potential predictor of outcome. Between 2003 and 2005, 37 patients required ECMO following corrective surgery for congenital heart disease. Records were reviewed retrospectively with emphasis on factors affecting survival to discharge. The comprehensive Aristotle complexity score was calculated for each patient. Overall, 28 patients (76%) survived to decannulation and 17 patients (46%) survived to discharge. There were 24 (65%) neonates and 10 patients (27%) with single ventricle physiology, with a hospital survival of 42% (10 of 24) and 50% (5 of 10), respectively. Univariate factors associated with survival included Aristotle score, duration of support, reexploration, multiple organ failure, and number of complications. Age, weight, and single-ventricle physiology were not significant. In a logistic regression model, an Aristotle score < 14 was identified as a predictor of survival (OR 0.12, CI 0.02-0.87). The Aristotle score is predictive of outcome in patients requiring postcardiotomy ECMO and may serve as a uniform criterion when comparing and evaluating quality of care and performance in this complex patient population.

Hyaluronic Acid in Vascular and Immune Homeostasis during Normal Pregnancy and Preeclampsia

PubMed Central

Ziganshina, M. M.; Pavlovich, S. V.; Bovin, N. V.; Sukhikh, G. T.

2016-01-01

Preeclampsia (PE) is a multisystem pathologic state that clinically manifests itself after the 20th week of pregnancy. It is characterized by high maternal and perinatal morbidity and mortality. According to modern concepts, the impairment of trophoblast invasion into maternal spiral arteries, leading to the development of ischemia in placenta, is considered to be the major pathogenetic factor of PE development. Ischemic lesions initiate the development of a systemic inflammatory response (SIR) and endothelial dysfunction, which is the main cause of the multiple organ failure in PE. Some data has appear indicating the importance of a glycans-forming endothelial glycocalyx and extracellular matrix (ECM) for placenta morphogenesis, as well as their role in the regulation of vascular permeability and vascular tone in hypertension disorders and, in particular, PE. Since intact glycocalyx and ECM are considered to be the major factors that maintain the physiological vascular tone and adequate intercellular interactions, their value in PE pathogenesis is underestimated. This review is focused on hyaluronic acid (HA) as the key glycan providing the organization and stabilization of the ECM and glycocalyx, its distribution in tissues in the case of presence or absence of placental pathology, as well as on the regulatory function of hyaluronic acids of various molecular weights in different physiological and pathophysiological processes. The summarized data will provide a better understanding of the PE pathogenesis, with the main focus on glycopathology. PMID:27795844

Use of erythrocyte indicators of health and condition in vertebrate ecophysiology: a review and appraisal.

PubMed

Johnstone, Christopher P; Lill, Alan; Reina, Richard D

2017-02-01

We review evidence for and against the use of erythrocyte indicators of health status and condition, parasite infection level and physiological stress in free-living vertebrates. The use of indicators that are measured directly from the blood, such as haemoglobin concentration, haematocrit and erythrocyte sedimentation rate, and parameters that are calculated from multiple measured metrics, such as mean cell volume, mean cell haemoglobin content or mean cell haemoglobin concentration is evaluated. The evidence for or against the use of any given metric is equivocal when the relevant research is considered in total, although there is sometimes strong support for using a particular metric in a particular taxon. Possibly the usefulness of these metrics is taxon, environment or condition specific. Alternatively, in an uncontrolled environment where multiple factors are influencing a metric, its response to environmental change will sometimes, but not always, be predictable. We suggest that (i) researchers should validate a metricfres utility before use, (ii) multiple metrics should be used to construct an overall erythrocyte profile for an individual or population, (iii) there is a need for researchers to compile reference ranges for free-living species, and (iv) some metrics which are useful under controlled, clinical conditions may not have the same utility or applicability for free-living vertebrates. Erythrocyte metrics provide useful information about health and condition that can be meaningfully interpreted in free-living vertebrates, but their use requires careful forethought about confounding factors. © 2015 Cambridge Philosophical Society.

Interorgan Communication Pathways in Physiology: Focus on Drosophila

PubMed Central

Droujinine, Ilia A.; Perrimon, Norbert

2017-01-01

Studies in mammals and Drosophila have demonstrated the existence and significance of secreted factors involved in communication between distal organs. In this review, primarily focusing on Drosophila, we examine the known interorgan communication factors and their functions, physiological inducers, and integration in regulating physiology. Moreover, we describe how organ-sensing screens in Drosophila can systematically identify novel conserved interorgan communication factors. Finally, we discuss how interorgan communication enabled and evolved as a result of specialization of organs. Together, we anticipate that future studies will establish a model for metazoan interorgan communication network (ICN) and how it is deregulated in disease. PMID:27732790

Interorgan Communication Pathways in Physiology: Focus on Drosophila.

PubMed

Droujinine, Ilia A; Perrimon, Norbert

2016-11-23

Studies in mammals and Drosophila have demonstrated the existence and significance of secreted factors involved in communication between distal organs. In this review, primarily focusing on Drosophila, we examine the known interorgan communication factors and their functions, physiological inducers, and integration in regulating physiology. Moreover, we describe how organ-sensing screens in Drosophila can systematically identify novel conserved interorgan communication factors. Finally, we discuss how interorgan communication enabled and evolved as a result of specialization of organs. Together, we anticipate that future studies will establish a model for metazoan interorgan communication network (ICN) and how it is deregulated in disease.

Understanding the Effects of Long-duration Space Flight on Astronant Functional Task Performance

NASA Technical Reports Server (NTRS)

Bloomberg, Jacob J.; Batson, Crystal D.; Buxton, Roxanne E.; Feiveson, Al H.; Kofman, Igor S.; Lee, Stuart M. C.; Miller, Chris A.; Mulavara, Ajitkumar P.; Peters, Brian T.; Phillips, Tiffany;

The Vitamin Nicotinamide: Translating Nutrition into Clinical Care

PubMed Central

Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

2009-01-01

Nicotinamide, the amide form of vitamin B3 (niacin), is changed to its mononucleotide compound with the enzyme nicotinic acide/nicotinamide adenylyl-transferase, and participates in the cellular energy metabolism that directly impacts normal physiology. However, nicotinamide also influences oxidative stress and modulates multiple pathways tied to both cellular survival and death. During disorders that include immune system dysfunction, diabetes, and aging-related diseases, nicotinamide is a robust cytoprotectant that blocks cellular inflammatory cell activation, early apoptotic phosphatidylserine exposure, and late nuclear DNA degradation. Nicotinamide relies upon unique cellular pathways that involve forkhead transcription factors, sirtuins, protein kinase B (Akt), Bad, caspases, and poly (ADP-ribose) polymerase that may offer a fine line with determining cellular longevity, cell survival, and unwanted cancer progression. If one is cognizant of the these considerations, it becomes evident that nicotinamide holds great potential for multiple disease entities, but the development of new therapeutic strategies rests heavily upon the elucidation of the novel cellular pathways that nicotinamide closely governs. PMID:19783937

Research on Hazardous States of Awareness and Physiological Factors in Aerospace Operations

NASA Technical Reports Server (NTRS)

Prinzel, Lawrence J., III

2002-01-01

The technical memorandum describes research conducted to examine the etiologies and nature of hazardous states of awareness and the psychophysiological factors involved in their onset in aerospace operations. A considerable amount of research has been conducted at NASA that examines psychological and human factors issues that may play a role in aviation safety. The technical memorandum describes some of the research that was conducted between 1998 and 2001, both in-house and as cooperative agreements, which addressed some of these issues. The research was sponsored as part of the physiological factors subelement of the Aviation Operation Systems (AOS) program and Physiological / Psychological Stressors and Factors project. Dr. Lance Prinzel is the Level III subelement lead and can be contacted at l.j.prinzel@larc.nasa.gov.

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.

Fractalkine and CX3CR1 Mediate a Novel Mechanism of Leukocyte Capture, Firm Adhesion, and Activation under Physiologic Flow

PubMed Central

Fong, Alan M.; Robinson, Lisa A.; Steeber, Douglas A.; Tedder, Thomas F.; Yoshie, Osamu; Imai, Toshio; Patel, Dhavalkumar D.

1998-01-01

Leukocyte migration into sites of inflammation involves multiple molecular interactions between leukocytes and vascular endothelial cells, mediating sequential leukocyte capture, rolling, and firm adhesion. In this study, we tested the role of molecular interactions between fractalkine (FKN), a transmembrane mucin-chemokine hybrid molecule expressed on activated endothelium, and its receptor (CX3CR1) in leukocyte capture, firm adhesion, and activation under physiologic flow conditions. Immobilized FKN fusion proteins captured resting peripheral blood mononuclear cells at physiologic wall shear stresses and induced firm adhesion of resting monocytes, resting and interleukin (IL)-2–activated CD8+ T lymphocytes and IL-2–activated NK cells. FKN also induced cell shape change in firmly adherent monocytes and IL-2–activated lymphocytes. CX3CR1-transfected K562 cells, but not control K562 cells, firmly adhered to FKN-expressing ECV-304 cells (ECV-FKN) and tumor necrosis factor α–activated human umbilical vein endothelial cells. This firm adhesion was not inhibited by pertussis toxin, EDTA/EGTA, or antiintegrin antibodies, indicating that the firm adhesion was integrin independent. In summary, FKN mediated the rapid capture, integrin-independent firm adhesion, and activation of circulating leukocytes under flow. Thus, FKN and CX3CR1 mediate a novel pathway for leukocyte trafficking. PMID:9782118

Injectable Hydrogels for Spinal Cord Repair: A Focus on Swelling and Intraspinal Pressure.

PubMed

Khaing, Zin Z; Ehsanipour, Arshia; Hofstetter, Christoph P; Seidlits, Stephanie K

Spinal cord injury (SCI) is a devastating condition that leaves patients with limited motor and sensory function at and below the injury site, with little to no hope of a meaningful recovery. Because of their ability to mimic multiple features of central nervous system (CNS) tissues, injectable hydrogels are being developed that can participate as therapeutic agents in reducing secondary injury and in the regeneration of spinal cord tissue. Injectable biomaterials can provide a supportive substrate for tissue regeneration, deliver therapeutic factors, and regulate local tissue physiology. Recent reports of increasing intraspinal pressure after SCI suggest that this physiological change can contribute to injury expansion, also known as secondary injury. Hydrogels contain high water content similar to native tissue, and many hydrogels absorb water and swell after formation. In the case of injectable hydrogels for the spinal cord, this process often occurs in or around the spinal cord tissue, and thus may affect intraspinal pressure. In the future, predictable swelling properties of hydrogels may be leveraged to control intraspinal pressure after injury. Here, we review the physiology of SCI, with special attention to the current clinical and experimental literature, underscoring the importance of controlling intraspinal pressure after SCI. We then discuss how hydrogel fabrication, injection, and swelling can impact intraspinal pressure in the context of developing injectable biomaterials for SCI treatment. © 2016 S. Karger AG, Basel.

Enhancing crop resilience to combined abiotic and biotic stress through the dissection of physiological and molecular crosstalk

PubMed Central

Kissoudis, Christos; van de Wiel, Clemens; Visser, Richard G. F.; van der Linden, Gerard

2014-01-01

Plants growing in their natural habitats are often challenged simultaneously by multiple stress factors, both abiotic and biotic. Research has so far been limited to responses to individual stresses, and understanding of adaptation to combinatorial stress is limited, but indicative of non-additive interactions. Omics data analysis and functional characterization of individual genes has revealed a convergence of signaling pathways for abiotic and biotic stress adaptation. Taking into account that most data originate from imposition of individual stress factors, this review summarizes these findings in a physiological context, following the pathogenesis timeline and highlighting potential differential interactions occurring between abiotic and biotic stress signaling across the different cellular compartments and at the whole plant level. Potential effects of abiotic stress on resistance components such as extracellular receptor proteins, R-genes and systemic acquired resistance will be elaborated, as well as crosstalk at the levels of hormone, reactive oxygen species, and redox signaling. Breeding targets and strategies are proposed focusing on either manipulation and deployment of individual common regulators such as transcription factors or pyramiding of non- (negatively) interacting components such as R-genes with abiotic stress resistance genes. We propose that dissection of broad spectrum stress tolerance conferred by priming chemicals may provide an insight on stress cross regulation and additional candidate genes for improving crop performance under combined stress. Validation of the proposed strategies in lab and field experiments is a first step toward the goal of achieving tolerance to combinatorial stress in crops. PMID:24904607

β2-Glycoprotein I Inhibits Vascular Endothelial Growth Factor-Induced Angiogenesis by Suppressing the Phosphorylation of Extracellular Signal-Regulated Kinase 1/2, Akt, and Endothelial Nitric Oxide Synthase

PubMed Central

Chiu, Wen-Chin; Chiou, Tzeon-Jye; Chung, Meng-Ju; Chiang, An-Na

2016-01-01

Angiogenesis is the process of new blood vessel formation, and it plays a key role in various physiological and pathological conditions. The β2-glycoprotein I (β2-GPI) is a plasma glycoprotein with multiple biological functions, some of which remain to be elucidated. This study aimed to identify the contribution of 2-GPI on the angiogenesis induced by vascular endothelial growth factor (VEGF), a pro-angiogenic factor that may regulate endothelial remodeling, and its underlying mechanism. Our results revealed that β2-GPI dose-dependently decreased the VEGF-induced increase in endothelial cell proliferation, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and the bromodeoxyuridine (BrdU) incorporation assays. Furthermore, incubation with both β2-GPI and deglycosylated β2-GPI inhibited the VEGF-induced tube formation. Our results suggest that the carbohydrate residues of β2-GPI do not participate in the function of anti-angiogenesis. Using in vivo Matrigel plug and angioreactor assays, we show that β2-GPI remarkably inhibited the VEGF-induced angiogenesis at a physiological concentration. Moreover, β2-GPI inhibited the VEGF-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), Akt, and endothelial nitric oxide synthase (eNOS). In summary, our in vitro and in vivo data reveal for the first time that β2-GPI inhibits the VEGF-induced angiogenesis and highlights the potential for β2-GPI in anti-angiogenic therapy. PMID:27579889

Using ecology to inform physiology studies: implications of high population density in the laboratory.

PubMed

Newman, Amy E M; Edmunds, Nicholas B; Ferraro, Shannon; Heffell, Quentin; Merritt, Gillian M; Pakkala, Jesse J; Schilling, Cory R; Schorno, Sarah

2015-03-15

Conspecific density is widely recognized as an important ecological factor across the animal kingdom; however, the physiological impacts are less thoroughly described. In fact, population density is rarely mentioned as a factor in physiological studies on captive animals and, when it is infrequently addressed, the animals used are reared and housed at densities far above those in nature, making the translation of results from the laboratory to natural systems difficult. We survey the literature to highlight this important ecophysiological gap and bring attention to the possibility that conspecific density prior to experimentation may be a critical factor influencing results. Across three taxa: mammals, birds, and fish, we present evidence from ecology that density influences glucocorticoid levels, immune function, and body condition with the intention of stimulating discussion and increasing consideration of population density in physiology studies. We conclude with several directives to improve the applicability of insights gained in the laboratory to organisms in the natural environment. Copyright © 2015 the American Physiological Society.

Physiological responses to environmental factors related to space flight. [hemodynamic and metabolic responses to weightlessness

NASA Technical Reports Server (NTRS)

Pace, N.

1973-01-01

Physiological base line data are established, and physiological procedures and instrumentation necessary for the automatic measurement of hemodynamic and metabolic parameters during prolonged periods of weightlessness are developed.

The IKK complex contributes to the induction of autophagy.

PubMed

Criollo, Alfredo; Senovilla, Laura; Authier, Hélène; Maiuri, Maria Chiara; Morselli, Eugenia; Vitale, Ilio; Kepp, Oliver; Tasdemir, Ezgi; Galluzzi, Lorenzo; Shen, Shensi; Tailler, Maximilien; Delahaye, Nicolas; Tesniere, Antoine; De Stefano, Daniela; Younes, Aména Ben; Harper, Francis; Pierron, Gérard; Lavandero, Sergio; Zitvogel, Laurence; Israel, Alain; Baud, Véronique; Kroemer, Guido

2010-02-03

In response to stress, cells start transcriptional and transcription-independent programs that can lead to adaptation or death. Here, we show that multiple inducers of autophagy, including nutrient depletion, trigger the activation of the IKK (IkappaB kinase) complex that is best known for its essential role in the activation of the transcription factor NF-kappaB by stress. Constitutively active IKK subunits stimulated autophagy and transduced multiple signals that operate in starvation-induced autophagy, including the phosphorylation of AMPK and JNK1. Genetic inhibition of the nuclear translocation of NF-kappaB or ablation of the p65/RelA NF-kappaB subunit failed to suppress IKK-induced autophagy, indicating that IKK can promote the autophagic pathway in an NF-kappaB-independent manner. In murine and human cells, knockout and/or knockdown of IKK subunits (but not that of p65) prevented the induction of autophagy in response to multiple stimuli. Moreover, the knockout of IKK-beta suppressed the activation of autophagy by food deprivation or rapamycin injections in vivo, in mice. Altogether, these results indicate that IKK has a cardinal role in the stimulation of autophagy by physiological and pharmacological stimuli.

Epigenomics of Hypertension

PubMed Central

Liang, Mingyu; Cowley, Allen W.; Mattson, David L.; Kotchen, Theodore A.; Liu, Yong

2013-01-01

Multiple genes and pathways are involved in the pathogenesis of hypertension. Epigenomic studies of hypertension are beginning to emerge and hold great promise of providing novel insights into the mechanisms underlying hypertension. Epigenetic marks or mediators including DNA methylation, histone modifications, and non-coding RNA can be studied at a genome or near-genome scale using epigenomic approaches. At the single gene level, several studies have identified changes in epigenetic modifications in genes expressed in the kidney that correlate with the development of hypertension. Systematic analysis and integration of epigenetic marks at the genome scale, demonstration of cellular and physiological roles of specific epigenetic modifications, and investigation of inheritance are among the major challenges and opportunities for future epigenomic and epigenetic studies of hypertension. Essential hypertension is a multifactorial disease involving multiple genetic and environmental factors and mediated by alterations in multiple biological pathways. Because the non-genetic mechanisms may involve epigenetic modifications, epigenomics is one of the latest concepts and approaches brought to bear on hypertension research. In this article, we summarize briefly the concepts and techniques for epigenomics, discuss the rationale for applying epigenomic approaches to study hypertension, and review the current state of this research area. PMID:24011581

Dual mechanisms regulating glutamate decarboxylases and accumulation of gamma-aminobutyric acid in tea (Camellia sinensis) leaves exposed to multiple stresses

PubMed Central

Mei, Xin; Chen, Yiyong; Zhang, Lingyun; Fu, Xiumin; Wei, Qing; Grierson, Don; Zhou, Ying; Huang, Yahui; Dong, Fang; Yang, Ziyin

2016-01-01

γ-Aminobutyric acid (GABA) is one of the major inhibitory neurotransmitters in the central nervous system. It has multiple positive effects on mammalian physiology and is an important bioactive component of tea (Camellia sinensis). GABA generally occurs at a very low level in plants but GABA content increases substantially after exposure to a range of stresses, especially oxygen-deficiency. During processing of tea leaves, a combination of anoxic stress and mechanical damage are essential for the high accumulation of GABA. This is believed to be initiated by a change in glutamate decarboxylase activity, but the underlying mechanisms are unclear. In the present study we characterized factors regulating the expression and activity of three tea glutamate decarboxylase genes (CsGAD1, 2, and 3), and their encoded enzymes. The results suggests that, unlike the model plant Arabidopsis thaliana, there are dual mechanisms regulating the accumulation of GABA in tea leaves exposed to multiple stresses, including activation of CsGAD1 enzymatic activity by calmodulin upon the onset of the stress and accumulation of high levels of CsGAD2 mRNA induced by a combination of anoxic stress and mechanical damage. PMID:27021285

Dual mechanisms regulating glutamate decarboxylases and accumulation of gamma-aminobutyric acid in tea (Camellia sinensis) leaves exposed to multiple stresses.

PubMed

Mei, Xin; Chen, Yiyong; Zhang, Lingyun; Fu, Xiumin; Wei, Qing; Grierson, Don; Zhou, Ying; Huang, Yahui; Dong, Fang; Yang, Ziyin

2016-03-29

γ-Aminobutyric acid (GABA) is one of the major inhibitory neurotransmitters in the central nervous system. It has multiple positive effects on mammalian physiology and is an important bioactive component of tea (Camellia sinensis). GABA generally occurs at a very low level in plants but GABA content increases substantially after exposure to a range of stresses, especially oxygen-deficiency. During processing of tea leaves, a combination of anoxic stress and mechanical damage are essential for the high accumulation of GABA. This is believed to be initiated by a change in glutamate decarboxylase activity, but the underlying mechanisms are unclear. In the present study we characterized factors regulating the expression and activity of three tea glutamate decarboxylase genes (CsGAD1, 2, and 3), and their encoded enzymes. The results suggests that, unlike the model plant Arabidopsis thaliana, there are dual mechanisms regulating the accumulation of GABA in tea leaves exposed to multiple stresses, including activation of CsGAD1 enzymatic activity by calmodulin upon the onset of the stress and accumulation of high levels of CsGAD2 mRNA induced by a combination of anoxic stress and mechanical damage.

Evaluating the Influence of Nutrition Determinants on Construction Workers' Food Choices.

PubMed

Okoro, Chioma Sylvia; Musonda, Innocent; Agumba, Justus

2017-11-01

Nutritional knowledge as well as economic, social, biological, and cultural factors have been known to determine an individual's food choices. Despite the existence of research on the factors which influence nutrition globally, there is little known about the extent to which these factors influence the food choices of construction workers, which in turn influence their health and safety during construction activities. The present article investigates the extent to which construction workers' nutrition is influenced by nutritional knowledge, as well as economic, environmental, social, psychological, and physiological factors. A field questionnaire survey was conducted on site construction workers in the Gauteng Province of South Africa. Principal components analysis and multiple regression analysis were used to analyze the data. Findings revealed that consumption of foods termed alternative foods including dairy products, eggs, nuts, fish, and cereals, was influenced by nutritional knowledge and resources. Foods termed traditional core foods were influenced by cultural background; foods termed secondary core foods comprising fruits and vegetables were influenced by economic factors, resources, and cultural background; while foods termed core foods were mostly influenced by nutritional knowledge. By providing evidence of the factors which most influence selection and consumption of certain foods by construction workers, relevant nutrition interventions will be designed and implemented, taking cognizance of these factors.

Evaluating the Influence of Nutrition Determinants on Construction Workers’ Food Choices

PubMed Central

Okoro, Chioma Sylvia; Musonda, Innocent; Agumba, Justus

2016-01-01

Nutritional knowledge as well as economic, social, biological, and cultural factors have been known to determine an individual’s food choices. Despite the existence of research on the factors which influence nutrition globally, there is little known about the extent to which these factors influence the food choices of construction workers, which in turn influence their health and safety during construction activities. The present article investigates the extent to which construction workers’ nutrition is influenced by nutritional knowledge, as well as economic, environmental, social, psychological, and physiological factors. A field questionnaire survey was conducted on site construction workers in the Gauteng Province of South Africa. Principal components analysis and multiple regression analysis were used to analyze the data. Findings revealed that consumption of foods termed alternative foods including dairy products, eggs, nuts, fish, and cereals, was influenced by nutritional knowledge and resources. Foods termed traditional core foods were influenced by cultural background; foods termed secondary core foods comprising fruits and vegetables were influenced by economic factors, resources, and cultural background; while foods termed core foods were mostly influenced by nutritional knowledge. By providing evidence of the factors which most influence selection and consumption of certain foods by construction workers, relevant nutrition interventions will be designed and implemented, taking cognizance of these factors. PMID:26821794

Next Steps Toward Understanding Human Habitation of Space: Environmental Impacts and Mechanisms

NASA Technical Reports Server (NTRS)

Globus, Ruth

2016-01-01

Entry into low earth orbit and beyond causes profound shifts in environmental conditions that have the potential to influence human productivity, long term health, and even survival. We now have evidence that microgravity, radiation and/or confinement in space can lead to demonstrably detrimental changes in the cardiovascular (e.g. vessel function, orthostatic intolerance), musculoskeletal (muscle atrophy, bone loss) and nervous (eye, neurovestibular) systems of astronauts. Because of both the limited number of astronauts who have flown (especially females) and the high degree of individual variability in the human population, important unanswered questions about responses to the space environment remain: What are the sex differences with respect to specific physiological systems? Are the responses age-dependent and/or reversible after return to Earth? Do observed detrimental changes that resemble accelerated aging progress continuously over time or plateau? What are the mechanisms of the biological responses? Answering these important questions certainly demands a multi-pronged approach, and the study of multicellular model organisms (such as rodents and flies) already has provided opportunities for exploring those questions in some detail. Recent long duration spaceflight experiments with rodents show that mice in space provide a mammalian model that uniquely combines the influence of reduced gravitational loading with increased physical activity. In addition, multiple investigators have shown that ground-based models that simulate aspects of spaceflight (including rodent hind limb unloading to mimic weightlessness and exposure to ionizing radiation), cause various transient and persistent detrimental consequences in multiple physiological systems. In general, we have found that adverse skeletal effects of simulated weightlessness and space radiation when combined, can be quantitatively, if not qualitatively, different from the influence of each environmental factor alone implying at least some shared underlying mechanisms. Thus, both ground based and spaceflight research utilizing model organisms provide the opportunity to better understand environmental factors and biological mechanisms that contribute to human health and survival in space.

Advancements in noncontact, multiparameter physiological measurements using a webcam.

PubMed

Poh, Ming-Zher; McDuff, Daniel J; Picard, Rosalind W

2011-01-01

We present a simple, low-cost method for measuring multiple physiological parameters using a basic webcam. By applying independent component analysis on the color channels in video recordings, we extracted the blood volume pulse from the facial regions. Heart rate (HR), respiratory rate, and HR variability (HRV, an index for cardiac autonomic activity) were subsequently quantified and compared to corresponding measurements using Food and Drug Administration-approved sensors. High degrees of agreement were achieved between the measurements across all physiological parameters. This technology has significant potential for advancing personal health care and telemedicine.

A Physiologically Based Pharmacokinetic Model for Pregnant Women to Predict the Pharmacokinetics of Drugs Metabolized Via Several Enzymatic Pathways.

PubMed

Dallmann, André; Ince, Ibrahim; Coboeken, Katrin; Eissing, Thomas; Hempel, Georg

2017-09-18

Physiologically based pharmacokinetic modeling is considered a valuable tool for predicting pharmacokinetic changes in pregnancy to subsequently guide in-vivo pharmacokinetic trials in pregnant women. The objective of this study was to extend and verify a previously developed physiologically based pharmacokinetic model for pregnant women for the prediction of pharmacokinetics of drugs metabolized via several cytochrome P450 enzymes. Quantitative information on gestation-specific changes in enzyme activity available in the literature was incorporated in a pregnancy physiologically based pharmacokinetic model and the pharmacokinetics of eight drugs metabolized via one or multiple cytochrome P450 enzymes was predicted. The tested drugs were caffeine, midazolam, nifedipine, metoprolol, ondansetron, granisetron, diazepam, and metronidazole. Pharmacokinetic predictions were evaluated by comparison with in-vivo pharmacokinetic data obtained from the literature. The pregnancy physiologically based pharmacokinetic model successfully predicted the pharmacokinetics of all tested drugs. The observed pregnancy-induced pharmacokinetic changes were qualitatively and quantitatively reasonably well predicted for all drugs. Ninety-seven percent of the mean plasma concentrations predicted in pregnant women fell within a twofold error range and 63% within a 1.25-fold error range. For all drugs, the predicted area under the concentration-time curve was within a 1.25-fold error range. The presented pregnancy physiologically based pharmacokinetic model can quantitatively predict the pharmacokinetics of drugs that are metabolized via one or multiple cytochrome P450 enzymes by integrating prior knowledge of the pregnancy-related effect on these enzymes. This pregnancy physiologically based pharmacokinetic model may thus be used to identify potential exposure changes in pregnant women a priori and to eventually support informed decision making when clinical trials are designed in this special population.

Stress Hormones and their Regulation in a Captive Dolphin Population

DTIC Science & Technology

2013-09-30

multiple environmental stressors, many of which are anthropogenic. The resulting stress response is mounted to manage immediate physiological needs. When...variability in stress hormones and 2) evaluating physiological and metabolic alterations that occur during stress in bottlenose dolphin. The...specific research objectives of this effort are to (1) establish protocols for improved sensitivity of low-level corticosteroids ( aldosterone and

Nutriproteomics: facts, concepts, and perspectives.

PubMed

Sauer, Sascha; Luge, Toni

2015-03-01

Nutrition is a basic component of life. Nowadays, human nutrition research focuses amongst others on health-related aspects of food ingredients and extracts, and on analyzing the outcomes of specific diets. Usually, food ingredients such as bioactive peptides come in complex matrices. Single compounds, multiple interactions thereof and the underlying food matrix can vary physiological response of the organism. Proteins and peptides derived from food and beverages can cause adverse allergic reactions but are in general required for multiple functions such as growth and homeostatic regulation. Endogenously expressed human proteins and peptides can be used as biomarkers to monitor physiological deregulation and the effects of food consumption. The intestinal microbiome seems to play a fundamental role in establishing and maintaining physiological regulation and in digesting proteins and peptides and other biomolecules derived from food. Notably, the subtle interplay of flavor naturals in food and beverages with olfactory receptors can result in establishing human taste preferences, which again influences overall physiology. This article presents basic approaches and concepts to address scientific questions in nutritional proteomics and discusses potential benefits of proteomics-based methodologies to help advance the field of molecular nutrition research. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Application of Physiologically Based Pharmacokinetic/Pharmacodynamic Modeling in Cumulative Risk Assessment for N-Methyl Carbamate Insecticides

EPA Science Inventory

Human exposure to xenobiotics may occur through multiple pathways and routes of entry punctuated by exposure intervals throughout a work or leisure day. Exposure to a single environmental chemical along multiple pathways and routes (aggregate exposure) may have an influence on an...

Diagnosing Secondary Students' Misconceptions of Photosynthesis and Respiration in Plants Using a Two-Tier Multiple Choice Instrument.

ERIC Educational Resources Information Center

Haslam, Filocha; Treagust, David F.

1987-01-01

Describes a multiple-choice instrument that reliably and validly diagnoses secondary students' understanding of photosynthesis and respiration in plants. Highlights the consistency of students' misconceptions across secondary levels and indicates a high percentage of students have misconceptions regarding plant physiology. (CW)

The effect of functional electrical stimulation on the physiological cost of gait in people with multiple sclerosis.

PubMed

Paul, L; Rafferty, D; Young, S; Miller, L; Mattison, P; McFadyen, A

2008-08-01

Functional electrical stimulation (FES) is used clinically in the management of drop foot in people suffering from neurological conditions. The aim of the study was to investigate the effects of FES, in terms of speed and physiological cost of gait, in people with multiple sclerosis (pwMS). Twelve pwMS and 12 healthy matched controls walked at their own preferred walking speed (PWS) for 5 min around a 10 m elliptical course. Subjects with MS completed the protocol with and without using their FES. In addition, control subjects completed the protocol twice more walking at the same PWS of the pwMS to which they were matched. Wearing FES lead to a significant improvement in walking speed (0.49 ms(-1) and 0.43 ms(-1) with and without their FES respectively; P<0.001) and a significant reduction in the physiological cost of gait (0.41 mL min(-1) kg(-1) m(-1) and 0.46 mL min(-1) kg(-1) m(-1) with and without FES respectively; P=0.017) in pwMS. The speed of walking, oxygen uptake, and physiological cost were significantly different between pwMS and controls both at preferred and matched speeds. Although pwMS exhibit a higher physiological cost of walking, FES offers an orthotic benefit to pwMS and should be considered as a possible treatment option.

Understanding the response to endurance exercise using a systems biology approach: combining blood metabolomics, transcriptomics and miRNomics in horses.

PubMed

Mach, Núria; Ramayo-Caldas, Yuliaxis; Clark, Allison; Moroldo, Marco; Robert, Céline; Barrey, Eric; López, Jesús Maria; Le Moyec, Laurence

2017-02-17

Endurance exercise in horses requires adaptive processes involving physiological, biochemical, and cognitive-behavioral responses in an attempt to regain homeostasis. We hypothesized that the identification of the relationships between blood metabolome, transcriptome, and miRNome during endurance exercise in horses could provide significant insights into the molecular response to endurance exercise. For this reason, the serum metabolome and whole-blood transcriptome and miRNome data were obtained from ten horses before and after a 160 km endurance competition. We obtained a global regulatory network based on 11 unique metabolites, 263 metabolic genes and 5 miRNAs whose expression was significantly altered at T1 (post- endurance competition) relative to T0 (baseline, pre-endurance competition). This network provided new insights into the cross talk between the distinct molecular pathways (e.g. energy and oxygen sensing, oxidative stress, and inflammation) that were not detectable when analyzing single metabolites or transcripts alone. Single metabolites and transcripts were carrying out multiple roles and thus sharing several biochemical pathways. Using a regulatory impact factor metric analysis, this regulatory network was further confirmed at the transcription factor and miRNA levels. In an extended cohort of 31 independent animals, multiple factor analysis confirmed the strong associations between lactate, methylene derivatives, miR-21-5p, miR-16-5p, let-7 family and genes that coded proteins involved in metabolic reactions primarily related to energy, ubiquitin proteasome and lipopolysaccharide immune responses after the endurance competition. Multiple factor analysis also identified potential biomarkers at T0 for an increased likelihood for failure to finish an endurance competition. To the best of our knowledge, the present study is the first to provide a comprehensive and integrated overview of the metabolome, transcriptome, and miRNome co-regulatory networks that may have a key role in regulating the metabolic and immune response to endurance exercise in horses.

Prospero-related homeobox 1 (Prox1) at the crossroads of diverse pathways during adult neural fate specification

PubMed Central

Stergiopoulos, Athanasios; Elkouris, Maximilianos; Politis, Panagiotis K.

2015-01-01

Over the last decades, adult neurogenesis in the central nervous system (CNS) has emerged as a fundamental process underlying physiology and disease. Recent evidence indicates that the homeobox transcription factor Prox1 is a critical intrinsic regulator of neurogenesis in the embryonic CNS and adult dentate gyrus (DG) of the hippocampus, acting in multiple ways and instructed by extrinsic cues and intrinsic factors. In the embryonic CNS, Prox1 is mechanistically involved in the regulation of proliferation vs. differentiation decisions of neural stem cells (NSCs), promoting cell cycle exit and neuronal differentiation, while inhibiting astrogliogenesis. During the complex differentiation events in adult hippocampal neurogenesis, Prox1 is required for maintenance of intermediate progenitors (IPs), differentiation and maturation of glutamatergic interneurons, as well as specification of DG cell identity over CA3 pyramidal fate. The mechanism by which Prox1 exerts multiple functions involves distinct signaling pathways currently not fully highlighted. In this mini-review, we thoroughly discuss the Prox1-dependent phenotypes and molecular pathways in adult neurogenesis in relation to different upstream signaling cues and cell fate determinants. In addition, we discuss the possibility that Prox1 may act as a cross-talk point between diverse signaling cascades to achieve specific outcomes during adult neurogenesis. PMID:25674048

Cellular and Physiological Effects of Anthrax Exotoxin and Its Relevance to Disease

PubMed Central

Lowe, David E.; Glomski, Ian J.

2012-01-01

Bacillus anthracis, the causative agent of anthrax, secretes a tri-partite exotoxin that exerts pleiotropic effects on the host. The purification of the exotoxin components, protective antigen, lethal factor, and edema factor allowed the rapid characterization of their physiologic effects on the host. As molecular biology matured, interest focused on the molecular mechanisms and cellular alterations induced by intoxication. Only recently have researchers begun to connect molecular and cellular knowledge back to the broader physiological effects of the exotoxin. This review focuses on the progress that has been made bridging molecular knowledge back to the exotoxin’s physiological effects on the host. PMID:22919667

Amyloid-β Homeostasis Bridges Inflammation, Synaptic Plasticity Deficits and Cognitive Dysfunction in Multiple Sclerosis.

PubMed

Stampanoni Bassi, Mario; Garofalo, Sara; Marfia, Girolama A; Gilio, Luana; Simonelli, Ilaria; Finardi, Annamaria; Furlan, Roberto; Sancesario, Giulia M; Di Giandomenico, Jonny; Storto, Marianna; Mori, Francesco; Centonze, Diego; Iezzi, Ennio

2017-01-01

Cognitive deficits are frequently observed in multiple sclerosis (MS), mainly involving processing speed and episodic memory. Both demyelination and gray matter atrophy can contribute to cognitive deficits in MS. In recent years, neuroinflammation is emerging as a new factor influencing clinical course in MS. Inflammatory cytokines induce synaptic dysfunction in MS. Synaptic plasticity occurring within hippocampal structures is considered as one of the basic physiological mechanisms of learning and memory. In experimental models of MS, hippocampal plasticity is profoundly altered by proinflammatory cytokines. Although mechanisms of inflammation-induced hippocampal pathology in MS are not completely understood, alteration of Amyloid-β (Aβ) metabolism is emerging as a key factor linking together inflammation, synaptic plasticity and neurodegeneration in different neurological diseases. We explored the correlation between concentrations of Aβ 1-42 and the levels of some proinflammatory and anti-inflammatory cytokines (interleukin-1β (IL-1β), IL1-ra, IL-8, IL-10, IL-12, tumor necrosis factor α (TNFα), interferon γ (IFNγ)) in the cerebrospinal fluid (CSF) of 103 remitting MS patients. CSF levels of Aβ 1-42 were negatively correlated with the proinflammatory cytokine IL-8 and positively correlated with the anti-inflammatory molecules IL-10 and interleukin-1 receptor antagonist (IL-1ra). Other correlations, although noticeable, were either borderline or not significant. Our data show that an imbalance between proinflammatory and anti-inflammatory cytokines may lead to altered Aβ homeostasis, representing a key factor linking together inflammation, synaptic plasticity and cognitive dysfunction in MS. This could be relevant to identify novel therapeutic approaches to hinder the progression of cognitive dysfunction in MS.

Cross-talk between abscisic acid-dependent and abscisic acid-independent pathways during abiotic stress.

PubMed

Roychoudhury, Aryadeep; Paul, Saikat; Basu, Supratim

2013-07-01

Salinity, drought and low temperature are the common forms of abiotic stress encountered by land plants. To cope with these adverse environmental factors, plants execute several physiological and metabolic responses. Both osmotic stress (elicited by water deficit or high salt) and cold stress increase the endogenous level of the phytohormone abscisic acid (ABA). ABA-dependent stomatal closure to reduce water loss is associated with small signaling molecules like nitric oxide, reactive oxygen species and cytosolic free calcium, and mediated by rapidly altering ion fluxes in guard cells. ABA also triggers the expression of osmotic stress-responsive (OR) genes, which usually contain single/multiple copies of cis-acting sequence called abscisic acid-responsive element (ABRE) in their upstream regions, mostly recognized by the basic leucine zipper-transcription factors (TFs), namely, ABA-responsive element-binding protein/ABA-binding factor. Another conserved sequence called the dehydration-responsive element (DRE)/C-repeat, responding to cold or osmotic stress, but not to ABA, occurs in some OR promoters, to which the DRE-binding protein/C-repeat-binding factor binds. In contrast, there are genes or TFs containing both DRE/CRT and ABRE, which can integrate input stimuli from salinity, drought, cold and ABA signaling pathways, thereby enabling cross-tolerance to multiple stresses. A strong candidate that mediates such cross-talk is calcium, which serves as a common second messenger for abiotic stress conditions and ABA. The present review highlights the involvement of both ABA-dependent and ABA-independent signaling components and their interaction or convergence in activating the stress genes. We restrict our discussion to salinity, drought and cold stress.

Perceived exertion. Antecedents and applications.

PubMed

Watt, B; Grove, R

1993-04-01

The field of perceived exertion has largely concerned itself with the problem of identifying the primary antecedents to this psychophysiological phenomenon. A vast literature has evolved addressing this problem, but it is fraught with contradictions. At this stage a comprehensive theory of perceived exertion does not exist. It is generally accepted that perception of exertion is dominated by physiological determinants. Physiological sensory cues have been separated into 2 categories: local factors (sensations from the working muscles and joints), and central factors (sensations from the cardiopulmonary system). Major reviews in this area generally agree that local factors dominate perception of exertion. Recent work in perceived exertion has placed an emphasis on examining the contributing psychological factors. Research into the psychological factors affecting perceived exertion has been highly fragmented with no apparent theoretical framework as a base. At the same time it is clear that an integration of psychological and physiological variables is required to obtain theoretically meaningful knowledge of this multidimensional construct. The assumed dominance of physiological factors has been challenged by the contention that in field situations, in which a variety of social psychological influences operate, psychological determinants of perceived exertion may be vastly more influential than previously estimated. Identification of the primary determinants of perceived exertion and knowledge of how these factors are integrated is vital for a concrete theory of perceived exertion to evolve.

ABNORMAL ALDOSTERONE PHYSIOLOGY AND CARDIO-METABOLIC RISK FACTORS

PubMed Central

Vaidya, Anand; Underwood, Patricia C.; Hopkins, Paul N.; Jeunemaitre, Xavier; Ferri, Claudio; Williams, Gordon H.; Adler, Gail K.

2013-01-01

Abnormal aldosterone physiology has been implicated in the pathogenesis of cardio-metabolic diseases. Single aldosterone measurements capture only a limited range of aldosterone physiology. New methods of characterizing aldosterone physiology may provide a more comprehensive understanding of its relationship with cardio-metabolic disease. We evaluated whether novel indices of aldosterone responses to dietary sodium modulation, the Sodium-modulated Aldosterone Suppression-Stimulation Index (SASSI for serum and SAUSSI for urine), could predict cardio-metabolic risk factors. We performed cross-sectional analyses on 539 subjects studied on liberal (LIB) and restricted (RES) sodium diets with serum and urinary aldosterone measurements. SASSI and SAUSSI were calculated as the ratio of aldosterone on LIB (maximally suppressed aldosterone) to aldosterone on RES (stimulated aldosterone) diets, and associated with risk factors using adjusted regression models. Cardio-metabolic risk factors associated with either impaired suppression of aldosterone on LIB diet, or impaired stimulation on RES diet, or both; in all of these individual cases, these risk factors associated with higher SASSI or SAUSSI. In the context of abnormalities that comprise the metabolic syndrome (MetS), there was a strong positive association between the number of MetS components (0–4) and both SASSI and SAUSSI (P<0.0001) that was independent of known aldosterone secretagogues (angiotensin II, corticotropin, potassium). SASSI and SAUSSI exhibited a high sensitivity in detecting normal individuals with zero MetS components (86% for SASSI and 83% for SAUSSI). Assessing the physiologic range of aldosterone responses may provide greater insights into adrenal pathophysiology. Dysregulated aldosterone physiology may contribute to, and/or result from, early cardio-metabolic abnormalities. PMID:23399714

Psychosocial factors in coronary heart disease

NASA Technical Reports Server (NTRS)

French, J. R. P., Jr.; Chaplan, R. D.

1969-01-01

The relationship between job satisfaction and coronary heart disease is explored for blue and white collar groups, different personalities and physiological risk factors. Differences found among administrators, engineers and scientists with regard to variables associated with heart disease are in terms of physiology, personality, reported job stress, and smoking.

Fatigue Factors in Regional Airline Operations

NASA Technical Reports Server (NTRS)

Rosekind, Mark R.; Weldon, Keri J.; Co, Elizabeth L.; Miller, Donna L.; Gregory, Kevin B.; Smith, Roy M.; Johnson, Julie M.; Gander, Philippa H.; Lebacqz, J. Victor

1994-01-01

This paper describes human sleep and circadian physiology regarding their role as contributors to fatigue engendered by flight operations. The demands of regional airline operations are then examined for potential areas where these physiological factors will be affected. Finally, approaches to systematically investigate these issues scientifically will be described.

Exercise and multiple sclerosis: physiological, psychological, and quality of life issues.

PubMed

Sutherland, G; Andersen, M B

2001-12-01

The case for the benefits of physical activity has been well documented in healthy individuals, and the potential for reducing the risk of mental and physical ill health is substantial. Yet, individuals with multiple sclerosis (MS) have long been advised to avoid participation in exercise in order to minimise the risk of exacerbations and symptoms of fatigue. There is, however, increasing interest in how acute and chronic exercise affect physiological and psychological functioning in MS. Much of the research has examined physiological tolerance to exercise and focused on responses in terms of heart rate, blood pressure, cardiorespiratory fitness, muscle function, and symptom stability. Little research has focused on understanding how exercise affects psychosocial functioning and brings about changes in depression, affect, mood, well-being, and quality of life. This paper provides a summary of the research exploring the efficacy of physical activity for people with MS. In addition, the key issues that face clinical practice are examined, and considerations for research are discussed.

Multimodality and nanoparticles in medical imaging

PubMed Central

Huang, Wen-Yen; Davis, Jason J.

2015-01-01

A number of medical imaging techniques are used heavily in the provision of spatially resolved information on disease and physiological status and accordingly play a critical role in clinical diagnostics and subsequent treatment. Though, for most imaging modes, contrast is potentially enhanced through the use of contrast agents or improved hardware or imaging protocols, no single methodology provides, in isolation, a detailed mapping of anatomy, disease markers or physiological status. In recent years, the concept of complementing the strengths of one imaging modality with those of another has come to the fore and been further bolstered by the development of fused instruments such as PET/CT and PET/MRI stations. Coupled with the continual development in imaging hardware has been a surge in reports of contrast agents bearing multiple functionality, potentially providing not only a powerful and highly sensitised means of co-localising physiological/disease status and anatomy, but also the tracking and delineation of multiple markers and indeed subsequent or simultaneous highly localized therapy (“theragnostics”). PMID:21409202

The Power of Physiology in Changing Landscapes: Considerations for the Continued Integration of Conservation and Physiology.

PubMed

Madliger, Christine L; Love, Oliver P

2015-10-01

The growing field of conservation physiology applies a diversity of physiological traits (e.g., immunological, metabolic, endocrine, and nutritional traits) to understand and predict organismal, population, and ecosystem responses to environmental change and stressors. Although the discipline of conservation physiology is gaining momentum, there is still a pressing need to better translate knowledge from physiology into real-world tools. The goal of this symposium, ‘‘Physiology in Changing Landscapes: An Integrative Perspective for Conservation Biology’’, was to highlight that many current investigations in ecological, evolutionary, and comparative physiology are necessary for understanding the applicability of physiological measures for conservation goals, particularly in the context of monitoring and predicting the health, condition, persistence, and distribution of populations in the face of environmental change. Here, we outline five major investigations common to environmental and ecological physiology that can contribute directly to the progression of the field of conservation physiology: (1) combining multiple measures of physiology and behavior; (2) employing studies of dose–responses and gradients; (3) combining a within-individual and population-level approach; (4) taking into account the context-dependency of physiological traits; and (5) linking physiological variables with fitness metrics. Overall, integrative physiologists have detailed knowledge of the physiological systems that they study; however, communicating theoretical and empirical knowledge to conservation biologists and practitioners in an approachable and applicable way is paramount to the practical development of physiological tools that will have a tangible impact for conservation.

Evaluating the validity of multiple imputation for missing physiological data in the national trauma data bank.

PubMed

Moore, Lynne; Hanley, James A; Lavoie, André; Turgeon, Alexis

2009-05-01

The National Trauma Data Bank (NTDB) is plagued by the problem of missing physiological data. The Glasgow Coma Scale score, Respiratory Rate and Systolic Blood Pressure are an essential part of risk adjustment strategies for trauma system evaluation and clinical research. Missing data on these variables may compromise the feasibility and the validity of trauma group comparisons. To evaluate the validity of Multiple Imputation (MI) for completing missing physiological data in the National Trauma Data Bank (NTDB), by assessing the impact of MI on 1) frequency distributions, 2) associations with mortality, and 3) risk adjustment. Analyses were based on 170,956 NTDB observations with complete physiological data (observed data set). Missing physiological data were artificially imposed on this data set and then imputed using MI (MI data set). To assess the impact of MI on risk adjustment, 100 pairs of hospitals were randomly selected with replacement and compared using adjusted Odds Ratios (OR) of mortality. OR generated by the observed data set were then compared to those generated by the MI data set. Frequency distributions and associations with mortality were preserved following MI. The median absolute difference between adjusted OR of mortality generated by the observed data set and by the MI data set was 3.6% (inter-quartile range: 2.4%-6.1%). This study suggests that, provided it is implemented with care, MI of missing physiological data in the NTDB leads to valid frequency distributions, preserves associations with mortality, and does not compromise risk adjustment in inter-hospital comparisons of mortality.

What have we learned about GPER function in physiology and disease from knockout mice?

PubMed Central

Prossnitz, Eric R.; Hathaway, Helen J.

2015-01-01

Estrogens, predominantly 17β-estradiol, exert diverse effects throughout the body in both normal and patho-physiology, during development and in reproductive, metabolic, endocrine, cardiovascular, nervous, musculoskeletal and immune systems. Estrogen and its receptors also play important roles in carcinogenesis and therapy, particularly for breast cancer. In addition to the classical nuclear estrogen receptors (ERα and ERβ) that traditionally mediate predominantly genomic signaling, the G protein-coupled estrogen receptor GPER has become recognized as a critical mediator of rapid signaling in response to estrogen. Mouse models, and in particular knockout (KO) mice, represent an important approach to understand the functions of receptors in normal physiology and disease. Whereas ERα KO mice display multiple significant defects in reproduction and mammary gland development, ERβ KO phenotypes are more limited, and GPER KO exhibit no reproductive deficits. However, the study of GPER KO mice over the last six years has revealed that GPER deficiency results in multiple physiological alterations including obesity, cardiovascular dysfunction, insulin resistance and glucose intolerance. In addition, the lack of estrogen-mediated effects in numerous tissues of GPER KO mice, studied in vivo or ex vivo, including those of the cardiovascular, endocrine, nervous and immune systems, reveals GPER as a genuine mediator of estrogen action. Importantly, GPER KO mice have also revealed roles for GPER in breast carcinogenesis and metastasis. In combination with the supporting effects of GPER-selective ligands and GPER knockdown approaches, GPER KO mice demonstrate the therapeutic potential of targeting GPER activity in diseases as diverse as obesity, diabetes, multiple sclerosis, hypertension, atherosclerosis, myocardial infarction, stroke and cancer. PMID:26189910

Multimodal integration of anatomy and physiology classes: How instructors utilize multimodal teaching in their classrooms

NASA Astrophysics Data System (ADS)

McGraw, Gerald M., Jr.

Multimodality is the theory of communication as it applies to social and educational semiotics (making meaning through the use of multiple signs and symbols). The term multimodality describes a communication methodology that includes multiple textual, aural, and visual applications (modes) that are woven together to create what is referred to as an artifact. Multimodal teaching methodology attempts to create a deeper meaning to course content by activating the higher cognitive areas of the student's brain, creating a more sustained retention of the information (Murray, 2009). The introduction of multimodality educational methodologies as a means to more optimally engage students has been documented within educational literature. However, studies analyzing the distribution and penetration into basic sciences, more specifically anatomy and physiology, have not been forthcoming. This study used a quantitative survey design to determine the degree to which instructors integrated multimodality teaching practices into their course curricula. The instrument used for the study was designed by the researcher based on evidence found in the literature and sent to members of three associations/societies for anatomy and physiology instructors: the Human Anatomy and Physiology Society; the iTeach Anatomy & Physiology Collaborate; and the American Physiology Society. Respondents totaled 182 instructor members of two- and four-year, private and public higher learning colleges collected from the three organizations collectively with over 13,500 members in over 925 higher learning institutions nationwide. The study concluded that the expansion of multimodal methodologies into anatomy and physiology classrooms is at the beginning of the process and that there is ample opportunity for expansion. Instructors continue to use lecture as their primary means of interaction with students. Email is still the major form of out-of-class communication for full-time instructors. Instructors with greater than 16 years of teaching anatomy and physiology are less likely to use video or animation in their classroom than instructors with fewer years.

Measuring breath acetone for monitoring fat loss: Review

PubMed Central

2015-01-01

Objective Endogenous acetone production is a by‐product of the fat metabolism process. Because of its small size, acetone appears in exhaled breath. Historically, endogenous acetone has been measured in exhaled breath to monitor ketosis in healthy and diabetic subjects. Recently, breath acetone concentration (BrAce) has been shown to correlate with the rate of fat loss in healthy individuals. In this review, the measurement of breath acetone in healthy subjects is evaluated for its utility in predicting fat loss and its sensitivity to changes in physiologic parameters. Results BrAce can range from 1 ppm in healthy non‐dieting subjects to 1,250 ppm in diabetic ketoacidosis. A strong correlation exists between increased BrAce and the rate of fat loss. Multiple metabolic and respiratory factors affect the measurement of BrAce. BrAce is most affected by changes in the following factors (in descending order): dietary macronutrient composition, caloric restriction, exercise, pulmonary factors, and other assorted factors that increase fat metabolism or inhibit acetone metabolism. Pulmonary factors affecting acetone exchange in the lung should be controlled to optimize the breath sample for measurement. Conclusions When biologic factors are controlled, BrAce measurement provides a non‐invasive tool for monitoring the rate of fat loss in healthy subjects. PMID:26524104

Measuring breath acetone for monitoring fat loss: Review.

PubMed

Anderson, Joseph C

2015-12-01

Endogenous acetone production is a by-product of the fat metabolism process. Because of its small size, acetone appears in exhaled breath. Historically, endogenous acetone has been measured in exhaled breath to monitor ketosis in healthy and diabetic subjects. Recently, breath acetone concentration (BrAce) has been shown to correlate with the rate of fat loss in healthy individuals. In this review, the measurement of breath acetone in healthy subjects is evaluated for its utility in predicting fat loss and its sensitivity to changes in physiologic parameters. BrAce can range from 1 ppm in healthy non-dieting subjects to 1,250 ppm in diabetic ketoacidosis. A strong correlation exists between increased BrAce and the rate of fat loss. Multiple metabolic and respiratory factors affect the measurement of BrAce. BrAce is most affected by changes in the following factors (in descending order): dietary macronutrient composition, caloric restriction, exercise, pulmonary factors, and other assorted factors that increase fat metabolism or inhibit acetone metabolism. Pulmonary factors affecting acetone exchange in the lung should be controlled to optimize the breath sample for measurement. When biologic factors are controlled, BrAce measurement provides a non-invasive tool for monitoring the rate of fat loss in healthy subjects. © 2015 The Authors Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

Bladder sensory physiology: neuroactive compounds and receptors, sensory transducers, and target-derived growth factors as targets to improve function

PubMed Central

Gonzalez, Eric J.; Merrill, Liana

2014-01-01

Urinary bladder dysfunction presents a major problem in the clinical management of patients suffering from pathological conditions and neurological injuries or disorders. Currently, the etiology underlying altered visceral sensations from the urinary bladder that accompany the chronic pain syndrome, bladder pain syndrome (BPS)/interstitial cystitis (IC), is not known. Bladder irritation and inflammation are histopathological features that may underlie BPS/IC that can change the properties of lower urinary tract sensory pathways (e.g., peripheral and central sensitization, neurochemical plasticity) and contribute to exaggerated responses of peripheral bladder sensory pathways. Among the potential mediators of peripheral nociceptor sensitization and urinary bladder dysfunction are neuroactive compounds (e.g., purinergic and neuropeptide and receptor pathways), sensory transducers (e.g., transient receptor potential channels) and target-derived growth factors (e.g., nerve growth factor). We review studies related to the organization of the afferent limb of the micturition reflex and discuss neuroplasticity in an animal model of urinary bladder inflammation to increase the understanding of functional bladder disorders and to identify potential novel targets for development of therapeutic interventions. Given the heterogeneity of BPS/IC and the lack of consistent treatment benefits, it is unlikely that a single treatment directed at a single target in micturition reflex pathways will have a mass benefit. Thus, the identification of multiple targets is a prudent approach, and use of cocktail treatments directed at multiple targets should be considered. PMID:24760999

Physiology and Endocrinology Symposium. Factors controlling puberty in beef heifers

USDA-ARS?s Scientific Manuscript database

The Physiology and Endocrinology Symposium on “Factors controlling puberty in beef heifers” was held at the joint annual meeting of the American Dairy Science Association and the American Society of Animal Science in New Orleans, Louisiana, USA, July 10 to 14, 2011. The objective of the symposium w...

Understanding How Solidarity Groups-A Community-Based Economic and Psychosocial Support Intervention-Can Affect Mental Health for Survivors of Conflict-Related Sexual Violence in Democratic Republic of the Congo.

PubMed

Koegler, Erica; Kennedy, Caitlin; Mrindi, Janvier; Bachunguye, Richard; Winch, Peter; Ramazani, Paul; Makambo, Maphie Tosha; Glass, Nancy

2018-06-01

Solidarity groups were established in eastern Democratic Republic of Congo to provide female survivors of conflict-related sexual violence an opportunity to generate income, establish networks of support, and cope with atrocities. Qualitative data were collected from 12 members of solidarity groups to explore factors that contributed to members' mental health. All women identified some improvement (physiological, psychological, economic, or social) since joining the solidarity group, but none of the women were free from ailments. Our findings suggest that a multifaceted intervention in women's own communities has the potential to improve multiple aspects of women's lives, including mental health.

A physiologically motivated sparse, compact, and smooth (SCS) approach to EEG source localization.

PubMed

Cao, Cheng; Akalin Acar, Zeynep; Kreutz-Delgado, Kenneth; Makeig, Scott

2012-01-01

Here, we introduce a novel approach to the EEG inverse problem based on the assumption that principal cortical sources of multi-channel EEG recordings may be assumed to be spatially sparse, compact, and smooth (SCS). To enforce these characteristics of solutions to the EEG inverse problem, we propose a correlation-variance model which factors a cortical source space covariance matrix into the multiplication of a pre-given correlation coefficient matrix and the square root of the diagonal variance matrix learned from the data under a Bayesian learning framework. We tested the SCS method using simulated EEG data with various SNR and applied it to a real ECOG data set. We compare the results of SCS to those of an established SBL algorithm.

Exploring student preferences with a Q-sort: the development of an individualized renal physiology curriculum.

PubMed

Roberts, John K; Hargett, Charles W; Nagler, Alisa; Jakoi, Emma; Lehrich, Ruediger W

2015-09-01

Medical education reform is underway, but the optimal course for change has yet to be seen. While planning for the redesign of a renal physiology course at the Duke School of Medicine, the authors used a Q-sort survey to assess students' attitudes and learning preferences to inform curricular change. The authors invited first-year medical students at the Duke School of Medicine to take a Q-sort survey on the first day of renal physiology. Students prioritized statements related to their understanding of renal physiology, learning preferences, preferred course characteristics, perceived clinical relevance of renal physiology, and interest in nephrology as a career. By-person factor analysis was performed using the centroid method. Three dominant factors were strongly defined by learning preferences: "readers" prefer using notes, a textbook, and avoid lectures; "social-auditory learners" prefer attending lectures, interactivity, and working with peers; and "visual learners" prefer studying images, diagrams, and viewing materials online. A smaller, fourth factor represented a small group of students with a strong predisposition against renal physiology and nephrology. In conclusion, the Q-sort survey identified and then described in detail the dominant viewpoints of our students. Learning style preferences better classified first-year students rather than any of the other domains. A more individualized curriculum would simultaneously cater to the different types of learners in the classroom. Copyright © 2015 The American Physiological Society.

Cardiovascular variability and introversion/extroversion, neuroticism and psychoticism.

PubMed

Burdick, J A; Van Dyck, B; Von Bargen, W J

1982-01-01

Forty-eight subjects were measured during a 10 min rest period for pulse wave velocity (PWV) and heart rate (HR) level and variability, using a Cyborg BL 907 instrument. These subjects were also evaluated by means of the Eysenck Personality Questionnaire for I-E, N, P and L. These data were factor analyzed. Five factors were identified which were accounted for 80.6% of the variance. These factors were: 'cardiovascular lability', 'heart rate time trends', 'cardiovascular balance', 'sex effects' and 'self reports'. The EPQ measurements separated from the physiological measurements in the factor analysis and none were found to be significantly loaded on any physiological variables. On the other hand, significant physiological correlations were found with N. This study adds a possible blood pressure and heart rate descripter to N.

Ecological distribution and population physiology defined by proteomics in a natural microbial community

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

Muller, R; Denef, Vincent; Kalnejals, Linda

An important challenge in microbial ecology is developing methods that simultaneously examine the physiology of organisms at the molecular level and their ecosystem level interactions in complex natural systems.We integrated extensive proteomic, geochemical, and biological information from 28 microbial communities collected from an acid mine drainage environment and representing a range of biofilm development stages and geochemical conditions to evaluate how the physiologies of the dominant and less abundant organisms change along environmental gradients. The initial colonist dominates across all environments, but its proteome changes between two stable states as communities diversify, implying that interspecies interactions affect this organism smore » metabolism. Its overall physiology is robust to abiotic environmental factors, but strong correlations exist between these factors and certain subsets of proteins, possibly accounting for its wide environmental distribution. Lower abundance populations are patchier in their distribution, and proteomic data indicate that their environmental niches may be constrained by specific sets of abiotic environmental factors. This research establishes an effective strategy to investigate ecological relationships between microbial physiology and the environment for whole communities in situ« less

Ecological distribution and population physiology defined by proteomics in a natural microbial community

USGS Publications Warehouse

Mueller, Ryan S.; Denef, Vincent J.; Kalnejais, Linda H.; Suttle, K. Blake; Thomas, Brian C.; Wilmes, Paul; Smith, Richard L.; Nordstrom, D. Kirk; McCleskey, R. Blaine; Shah, Menesh B.; VerBekmoes, Nathan C.; Hettich, Robert L.; Banfield, Jillian F.

2010-01-01

An important challenge in microbial ecology is developing methods that simultaneously examine the physiology of organisms at the molecular level and their ecosystem level interactions in complex natural systems. We integrated extensive proteomic, geochemical, and biological information from 28 microbial communities collected from an acid mine drainage environment and representing a range of biofilm development stages and geochemical conditions to evaluate how the physiologies of the dominant and less abundant organisms change along environmental gradients. The initial colonist dominates across all environments, but its proteome changes between two stable states as communities diversify, implying that interspecies interactions affect this organism's metabolism. Its overall physiology is robust to abiotic environmental factors, but strong correlations exist between these factors and certain subsets of proteins, possibly accounting for its wide environmental distribution. Lower abundance populations are patchier in their distribution, and proteomic data indicate that their environmental niches may be constrained by specific sets of abiotic environmental factors. This research establishes an effective strategy to investigate ecological relationships between microbial physiology and the environment for whole communities in situ.

Biogastronomy: Factors that determine the biological response to meal ingestion.

PubMed

Pribic, T; Azpiroz, F

2018-02-02

The biological response to a meal includes physiological changes, primarily related to the digestive process, and a sensory experience, involving sensations related to the homeostatic control of food consumption, eg, satiety and fullness, with a hedonic dimension, ie associated with changes in digestive well-being and mood. The responses to a meal include a series of events before, during and after ingestion. While much attention has been paid to the events before and during ingestion, relatively little is known about the postprandial sensations, which are key to the gastronomical experience. The aim of this narrative review is to provide a comprehensive overview and to define the framework to investigate the factors that determine the postprandial experience. Based on a series of proof-of-concept studies and related information, we propose that the biological responses to a meal depend on the characteristics of the meal, primarily its palatability and composition, and the responsiveness of the guest, which may be influenced by multiple previous and concurrent conditioning factors. This information provides the scientific backbone to the development of personalized gastronomy. © 2018 John Wiley & Sons Ltd.

Biomaterial-Stabilized Soft Tissue Healing for Healing of Critical-Sized Bone Defects: the Masquelet Technique.

PubMed

Tarchala, Magdalena; Harvey, Edward J; Barralet, Jake

2016-03-01

Critical-sized bone defects present a significant burden to the medical community due to their challenging treatment. However, a successful limb-salvaging technique, the Masquelet Technique (MT), has significantly improved the prognosis of many segmental bone defects in helping to restore form and function. Although the Masquelet Technique has proven to be clinically effective, the physiology of the healing it induces is not well understood. Multiple modifiable factors have been implicated by various surgical and research teams, but no single factor has been proven to be critical to the success of the Masquelet Technique. In this review the most recent clinical and experimental evidence that supports and helps to decipher the traditional Masquelet, as well as the modifiable factors and their effect on the success of the technique are discussed. In addition, future developments for the integration of the traditional Masquelet Technique with the use of alternative biomaterials to increase the effectiveness and expand the clinical applicability of the Masquelet Technique are reviewed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Longitudinal Associations of Parental Emotion Socialization and Children's Emotion Regulation: The Moderating Role of ADHD Symptomatology.

PubMed

Breaux, Rosanna P; McQuade, Julia D; Harvey, Elizabeth A; Zakarian, Rebecca J

2018-05-01

Theory and research suggest that parents' reactions to children's emotions play a critical role in teaching children effective emotion regulation (ER) skills, but no studies have directly examined the role that parent emotion socialization plays in the development of ER in children with ADHD. Gaining insight into the causes of impaired ER, particularly in youth with ADHD who are known to have poor ER, has important theoretical and translational significance. The present study is the first to longitudinally examine whether emotion socialization predicts later physiological and adult-reported measures of ER in children with and without ADHD. It also sought to determine if these relations are moderated by ADHD symptoms. Participants were 61 children (31 girls, 30 boys; M = 10.67 years, SD = 1.28) with and without clinically significant ADHD symptoms. At Time 1, parent reports of emotion socialization and parent- and teacher-report of child ADHD symptoms were collected. At Time 2, child ER measures were collected based on parent- and teacher-report and physiological reactivity during an impossible puzzle and a social rejection task. Physiological measures included respiratory sinus arrhythmia and skin conductance level (SCL). Supportive parenting practices were associated with better parent-rated emotion regulation skills for all children and greater SCL reactivity for children with high ADHD symptoms. Non-supportive parenting reactions were associated with greater adult-rated emotional lability for children with high ADHD symptoms. Results highlight the importance of considering multiple aspects of ER, including physiological manifestations. Findings suggest that parents' use of adaptive emotion socialization practices may serve as a protective factor for children's ER development and may be particularly critical for youth with ADHD. Our findings support the use of interventions addressing parent emotion socialization to help foster better ER in children.

Three-Dimensional Normal Human Neutral Progenitor Tissue-Like Assemblies: A Model for Persistent Varicella-Zoster Virus Infection and Platform to Study Oxidate Stress and Damage in Multiple Hit Scenarios

NASA Technical Reports Server (NTRS)

Goodwin, Thomas J.; McCarthy, M.; Osterrieder, N.; Cohrs, R. J.; Kaufer, B. B.

2014-01-01

The environment of space results in a multitude of challenges to the human physiology that present barriers to extended habitation and exploration. Over 40 years of investigation to define countermeasures to address space flight adaptation has left gaps in our knowledge regarding mitigation strategies partly due to the lack of investigative tools, monitoring strategies, and real time diagnostics to understand the central causative agent(s) responsible for physiologic adaptation and maintaining homeostasis. Spaceflight-adaptation syndrome is the combination of space environmental conditions and the synergistic reaction of the human physiology. Our work addresses the role of oxidative stress and damage (OSaD) as a negative and contributing Risk Factor (RF) in the following areas of combined spaceflight related dysregulation: i) radiation induced cellular damage [1], [2] ii) immune impacts and the inflammatory response [3], [4] and iii) varicella zoster virus (VZV) reactivation [5]. Varicella-zoster (VZV)/Chicken Pox virus is a neurotropic human alphaherpes virus resulting in varicella upon primary infection, suppressed by the immune system becomes latent in ganglionic neurons, and reactivates under stress events to re-express in zoster and possibly shingles. Our laboratory has developed a complex three-dimensional (3D) normal human neural tissue model that emulates several characteristics of the human trigeminal ganglia (TG) and allows the study of combinatorial experimentation which addresses, simultaneously, OSaD associated with Spaceflight adaptation and habitation [6]. By combining the RFs of microgravity, radiation, and viral infection we will demonstrate that living in the space environment leads to significant physiological consequences for the peripheral and subsequently the central nervous system (PNS, CNS) associated with OSaD generation and consequentially endangers long-duration and exploration-class missions.

Physiologic Impact of Circulating RBC Microparticles upon Blood-Vascular Interactions

PubMed Central

Said, Ahmed S.; Rogers, Stephen C.; Doctor, Allan

2018-01-01

Here, we review current data elucidating the role of red blood cell derived microparticles (RMPs) in normal vascular physiology and disease progression. Microparticles (MPs) are submicron-size, membrane-encapsulated vesicles derived from various parent cell types. MPs are produced in response to numerous stimuli that promote a sequence of cytoskeletal and membrane phospholipid changes and resulting MP genesis. MPs were originally considered as potential biomarkers for multiple disease processes and more recently are recognized to have pleiotropic biological effects, most notably in: promotion of coagulation, production and handling of reactive oxygen species, immune modulation, angiogenesis, and in initiating apoptosis. RMPs, specifically, form normally during RBC maturation in response to injury during circulation, and are copiously produced during processing and storage for transfusion. Notably, several factors during RBC storage are known to trigger RMP production, including: increased intracellular calcium, increased potassium leakage, and energy failure with ATP depletion. Of note, RMP composition differs markedly from that of intact RBCs and the nature/composition of RMP components are affected by the specific circumstances of RMP genesis. Described RMP bioactivities include: promotion of coagulation, immune modulation, and promotion of endothelial adhesion as well as influence upon vasoregulation via influence upon nitric oxide (NO) bioavailability. Of particular relevance, RMPs scavenge NO more avidly than do intact RBCs; this physiology has been proposed to contribute to the impaired oxygen delivery homeostasis that may be observed following transfusion. In summary, RMPs are submicron particles released from RBCs, with demonstrated vasoactive properties that appear to disturb oxygen delivery homeostasis. The clinical impact of RMPs in normal and patho-physiology and in transfusion recipients is an area of continued investigation. PMID:29379445

Physiologic Impact of Circulating RBC Microparticles upon Blood-Vascular Interactions.

PubMed

Said, Ahmed S; Rogers, Stephen C; Doctor, Allan

2017-01-01

Here, we review current data elucidating the role of red blood cell derived microparticles (RMPs) in normal vascular physiology and disease progression. Microparticles (MPs) are submicron-size, membrane-encapsulated vesicles derived from various parent cell types. MPs are produced in response to numerous stimuli that promote a sequence of cytoskeletal and membrane phospholipid changes and resulting MP genesis. MPs were originally considered as potential biomarkers for multiple disease processes and more recently are recognized to have pleiotropic biological effects, most notably in: promotion of coagulation, production and handling of reactive oxygen species, immune modulation, angiogenesis, and in initiating apoptosis. RMPs, specifically, form normally during RBC maturation in response to injury during circulation, and are copiously produced during processing and storage for transfusion. Notably, several factors during RBC storage are known to trigger RMP production, including: increased intracellular calcium, increased potassium leakage, and energy failure with ATP depletion. Of note, RMP composition differs markedly from that of intact RBCs and the nature/composition of RMP components are affected by the specific circumstances of RMP genesis. Described RMP bioactivities include: promotion of coagulation, immune modulation, and promotion of endothelial adhesion as well as influence upon vasoregulation via influence upon nitric oxide (NO) bioavailability. Of particular relevance, RMPs scavenge NO more avidly than do intact RBCs; this physiology has been proposed to contribute to the impaired oxygen delivery homeostasis that may be observed following transfusion. In summary, RMPs are submicron particles released from RBCs, with demonstrated vasoactive properties that appear to disturb oxygen delivery homeostasis. The clinical impact of RMPs in normal and patho-physiology and in transfusion recipients is an area of continued investigation.

Physiological and Functional Alterations after Spaceflight and Bed Rest.

PubMed

Mulavara, Ajitkumar P; Peters, Brian T; Miller, Chris A; Kofman, Igor S; Reschke, Millard F; Taylor, Laura C; Lawrence, Emily L; Wood, Scott J; Laurie, Steven S; Lee, Stuart M C; Buxton, Roxanne E; May-Phillips, Tiffany R; Stenger, Michael B; Ploutz-Snyder, Lori L; Ryder, Jeffrey W; Feiveson, Alan H; Bloomberg, Jacob J

2018-04-03

Exposure to microgravity causes alterations in multiple physiological systems, potentially impacting the ability of astronauts to perform critical mission tasks. The goal of this study was to determine the effects of spaceflight on functional task performance and to identify the key physiological factors contributing to their deficits. A test battery comprised of 7 functional tests and 15 physiological measures was used to investigate the sensorimotor, cardiovascular and neuromuscular adaptations to spaceflight. Astronauts were tested before and after 6-month spaceflights. Subjects were also tested before and after 70 days of 6° head-down bed rest, a spaceflight analog, to examine the role of axial body unloading on the spaceflight results. These subjects included Control and Exercise groups to examine the effects of exercise during bed rest. Spaceflight subjects showed the greatest decrement in performance during functional tasks that required the greatest demand for dynamic control of postural equilibrium which was paralleled by similar decrements in sensorimotor tests that assessed postural and dynamic gait control. Other changes included reduced lower limb muscle performance and increased heart rate to maintain blood pressure. Exercise performed during bed rest prevented detrimental change in neuromuscular and cardiovascular function, however, both bed rest groups experienced functional and balance deficits similar to spaceflight subjects. Bed rest data indicates that body support unloading experienced during spaceflight contributes to postflight postural control dysfunction. Further, the bed rest results in the Exercise group of subjects confirm that resistance and aerobic exercises performed during spaceflight can play an integral role in maintaining neuromuscular and cardiovascular function, which can help in reducing decrements in functional performance. These results indicate that a countermeasure to mitigate postflight postural control dysfunction is required to maintain functional performance.

In vitro oral drug permeation models: the importance of taking physiological and physico-chemical factors into consideration.

PubMed

Joubert, Ruan; Steyn, Johan Dewald; Heystek, Hendrik Jacobus; Steenekamp, Jan Harm; Du Preez, Jan Lourens; Hamman, Josias Hendrik

2017-02-01

The assessment of intestinal membrane permeability properties of new chemical entities is a crucial step in the drug discovery and development process and a variety of in vitro models, methods and techniques are available to estimate the extent of oral drug absorption in humans. However, variations in certain physiological and physico-chemical factors are often not reflected in the results and the complex dynamic interplay between these factors is sometimes oversimplified with in vitro models. Areas covered: In vitro models to evaluate drug pharmacokinetics are briefly outlined, while both physiological and physico-chemical factors that may have an influence on these techniques are critically reviewed. The shortcomings identified for some of the in vitro techniques are discussed in conjunction with novel ways to improve and thereby overcome some challenges. Expert opinion: Although conventional in vitro methods and theories are used as basic guidelines to predict drug absorption, critical evaluations have identified some shortcomings. Advancements in technology have made it possible to investigate and understand the role of physiological and physico-chemical factors in drug delivery more clearly, which can be used to improve and refine the techniques to more closely mimic the in vivo environment.

Effect of environmental and physiological factors on the antibacterial activity of Curvularia haloperoxidase system against Escherichia coli.

PubMed

Hansen, E H; Schäfer, T; Molin, S; Gram, L

2005-01-01

The aim of this study was to investigate the influence of environmental and physiological factors on the susceptibility of Escherichia coli to the Curvularia haloperoxidase system. The Curvularia haloperoxidase system is a novel enzyme system that produces reactive oxygen species which have an antimicrobial effect. Escherichia coli MG1655 was exposed to the Curvularia haloperoxidase system under different temperatures and NaCl concentrations and after exposure to different stress factors. Temperature clearly affected enzymatic activity with increasing antibacterial effect at increasing temperature. The presence of NaCl interfered with the enzyme system and in the presence of 1% NaCl, no antibacterial effect could be observed at pH 7. Cells grown at pH 8.0 were in one experiment more resistant than cells grown at pH 6.5, whereas cells grown in the presence of 2% NaCl were more susceptible to the Curvularia haloperoxidase system. Environmental and physiological factors can affect the antibacterial activity of the Curvularia haloperoxidase system. The study demonstrates a systematic approach in assessing the effect of environmental and physiological factors on microbial susceptibility to biocides. Such information is crucial for prediction of application as well as potential side-effects.

Endothelin-1 gene regulation

PubMed Central

Stow, Lisa R.; Jacobs, Mollie E.; Wingo, Charles S.; Cain, Brian D.

2011-01-01

Over two decades of research have demonstrated that the peptide hormone endothelin-1 (ET-1) plays multiple, complex roles in cardiovascular, neural, pulmonary, reproductive, and renal physiology. Differential and tissue-specific production of ET-1 must be tightly regulated in order to preserve these biologically diverse actions. The primary mechanism thought to control ET-1 bioavailability is the rate of transcription from the ET-1 gene (edn1). Studies conducted on a variety of cell types have identified key transcription factors that govern edn1 expression. With few exceptions, the cis-acting elements bound by these factors have been mapped in the edn1 regulatory region. Recent evidence has revealed new roles for some factors originally believed to regulate edn1 in a tissue or hormone-specific manner. In addition, other mechanisms involved in epigenetic regulation and mRNA stability have emerged as important processes for regulated edn1 expression. The goal of this review is to provide a comprehensive overview of the specific factors and signaling systems that govern edn1 activity at the molecular level.—Stow, L. R., Jacobs, M. E., Wingo, C. S., Cain, B. D. Endothelin-1 gene regulation. PMID:20837776

Transcription factors involved in retinogenesis are co-opted by the circadian clock following photoreceptor differentiation.

PubMed

Laranjeiro, Ricardo; Whitmore, David

2014-07-01

The circadian clock is known to regulate a wide range of physiological and cellular processes, yet remarkably little is known about its role during embryo development. Zebrafish offer a unique opportunity to explore this issue, not only because a great deal is known about key developmental events in this species, but also because the clock starts on the very first day of development. In this study, we identified numerous rhythmic genes in zebrafish larvae, including the key transcriptional regulators neurod and cdx1b, which are involved in neuronal and intestinal differentiation, respectively. Rhythmic expression of neurod and several additional transcription factors was only observed in the developing retina. Surprisingly, these rhythms in expression commenced at a stage of development after these transcription factors are known to have played their essential role in photoreceptor differentiation. Furthermore, this circadian regulation was maintained in adult retina. Thus, once mature photoreceptors are formed, multiple retinal transcription factors fall under circadian clock control, at which point they appear to play a new and important role in regulating rhythmic elements in the phototransduction pathway. © 2014. Published by The Company of Biologists Ltd.

Evaluation of slice accelerations using multiband echo planar imaging at 3 Tesla

PubMed Central

Xu, Junqian; Moeller, Steen; Auerbach, Edward J.; Strupp, John; Smith, Stephen M.; Feinberg, David A.; Yacoub, Essa; Uğurbil, Kâmil

2013-01-01

We evaluate residual aliasing among simultaneously excited and acquired slices in slice accelerated multiband (MB) echo planar imaging (EPI). No in-plane accelerations were used in order to maximize and evaluate achievable slice acceleration factors at 3 Tesla. We propose a novel leakage (L-) factor to quantify the effects of signal leakage between simultaneously acquired slices. With a standard 32-channel receiver coil at 3 Tesla, we demonstrate that slice acceleration factors of up to eight (MB = 8) with blipped controlled aliasing in parallel imaging (CAIPI), in the absence of in-plane accelerations, can be used routinely with acceptable image quality and integrity for whole brain imaging. Spectral analyses of single-shot fMRI time series demonstrate that temporal fluctuations due to both neuronal and physiological sources were distinguishable and comparable up to slice-acceleration factors of nine (MB = 9). The increased temporal efficiency could be employed to achieve, within a given acquisition period, higher spatial resolution, increased fMRI statistical power, multiple TEs, faster sampling of temporal events in a resting state fMRI time series, increased sampling of q-space in diffusion imaging, or more quiet time during a scan. PMID:23899722

The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish

NASA Astrophysics Data System (ADS)

Wenger, Amelia S.; Whinney, James; Taylor, Brett; Kroon, Frederieke

2016-06-01

Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change.

The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish.

PubMed

Wenger, Amelia S; Whinney, James; Taylor, Brett; Kroon, Frederieke

2016-06-28

Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change.

The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish

PubMed Central

Wenger, Amelia S.; Whinney, James; Taylor, Brett; Kroon, Frederieke

2016-01-01

Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change. PMID:27350589

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

PubMed

Castellani, John W; Young, Andrew J

2016-04-01

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

Stress and serial adult metamorphosis: multiple roles for the stress axis in socially regulated sex change.

PubMed

Solomon-Lane, Tessa K; Crespi, Erica J; Grober, Matthew S

2013-01-01

Socially regulated sex change in teleost fishes is a striking example of social status information regulating biological function in the service of reproductive success. The establishment of social dominance in sex changing species is translated into a cascade of changes in behavior, physiology, neuroendocrine function, and morphology that transforms a female into a male, or vice versa. The hypothalamic-pituitary-interrenal axis (HPI, homologous to HP-adrenal axis in mammals and birds) has been hypothesized to play a mechanistic role linking status to sex change. The HPA/I axis responds to environmental stressors by integrating relevant external and internal cues and coordinating biological responses including changes in behavior, energetics, physiology, and morphology (i.e., metamorphosis). Through actions of both corticotropin-releasing factor and glucocorticoids, the HPA/I axis has been implicated in processes central to sex change, including the regulation of agonistic behavior, social status, energetic investment, and life history transitions. In this paper, we review the hypothesized roles of the HPA/I axis in the regulation of sex change and how those hypotheses have been tested to date. We include original data on sex change in the bluebanded goby (Lythyrpnus dalli), a highly social fish capable of bidirectional sex change. We then propose a model for HPA/I involvement in sex change and discuss how these ideas might be tested in the future. Understanding the regulation of sex change has the potential to elucidate evolutionarily conserved mechanisms responsible for translating pertinent information about the environment into coordinated biological changes along multiple body axes.

Stress and serial adult metamorphosis: multiple roles for the stress axis in socially regulated sex change

PubMed Central

Solomon-Lane, Tessa K.; Crespi, Erica J.; Grober, Matthew S.

2013-01-01

Socially regulated sex change in teleost fishes is a striking example of social status information regulating biological function in the service of reproductive success. The establishment of social dominance in sex changing species is translated into a cascade of changes in behavior, physiology, neuroendocrine function, and morphology that transforms a female into a male, or vice versa. The hypothalamic-pituitary-interrenal axis (HPI, homologous to HP-adrenal axis in mammals and birds) has been hypothesized to play a mechanistic role linking status to sex change. The HPA/I axis responds to environmental stressors by integrating relevant external and internal cues and coordinating biological responses including changes in behavior, energetics, physiology, and morphology (i.e., metamorphosis). Through actions of both corticotropin-releasing factor and glucocorticoids, the HPA/I axis has been implicated in processes central to sex change, including the regulation of agonistic behavior, social status, energetic investment, and life history transitions. In this paper, we review the hypothesized roles of the HPA/I axis in the regulation of sex change and how those hypotheses have been tested to date. We include original data on sex change in the bluebanded goby (Lythyrpnus dalli), a highly social fish capable of bidirectional sex change. We then propose a model for HPA/I involvement in sex change and discuss how these ideas might be tested in the future. Understanding the regulation of sex change has the potential to elucidate evolutionarily conserved mechanisms responsible for translating pertinent information about the environment into coordinated biological changes along multiple body axes. PMID:24265604

Crew performance monitoring: Putting some feeling into it

NASA Astrophysics Data System (ADS)

Pattyn, N.; Migeotte, P.-F.; Morais, J.; Soetens, E.; Cluydts, R.; Kolinsky, R.

2009-08-01

Two hypotheses have been invoked so far to explain performance decrements in space: the microgravity hypothesis and the multiple stressors hypothesis. Furthermore, previous investigations of cognitive performance did not specifically target executive functions. The aim of this study was to investigate the impact of operational stress on cognitive control, towards both neutral and emotionally loaded material, using both psychometric and physiological indicators (autonomic nervous system activity computed through cardio-respiratory recordings). We applied the same design in a study on student pilots (N=12) in baseline conditions and right before a major evaluation flight and on astronauts (N=3) before, during and after a short-duration spaceflight. To address the problem of scarcity of subjects, we applied analytical methods derived from neuropsychology: comparing each astronaut treated as a single subject to a group of carefully matched controls (N=13). Results from both student pilots and astronauts showed that operational stress resulted in failing cognitive control, especially on emotionally loaded material that was relevant to the subjects' current concern. This impaired cognitive control was associated with a decreased physiological reactivity during mental tasks. Furthermore, for astronauts, this performance decrement appeared on the last data-collection before launch and lasted for the two in-flight measurements. These results thus allow us to conclude that: (i) performance testing including an emotional dimension seems more sensitive to operational stress, (ii) decreased heart rate reactivity was associated with impaired cognitive control and (iii) microgravity is not the sole causal factor of potential performance decrements in space, which are more likely due to the combination of multiple stressors.

Differences Between Gait on Stairs and Flat Surfaces in Relation to Fall Risk and Future Falls.

PubMed

Wang, Kejia; Delbaere, Kim; Brodie, Matthew A D; Lovell, Nigel H; Kark, Lauren; Lord, Stephen R; Redmond, Stephen J

2017-11-01

We used body-worn inertial sensors to quantify differences in semi-free-living gait between stairs and on normal flat ground in older adults, and investigated the utility of assessing gait on these terrains for predicting the occurrence of multiple falls. Eighty-two community-dwelling older adults wore two inertial sensors, on the lower back and the right ankle, during several bouts of walking on flat surfaces and up and down stairs, in between rests and activities of daily living. Derived from the vertical acceleration at the lower back, step rate was calculated from the signal's fundamental frequency. Step rate variability was the width of this fundamental frequency peak from the signal's power spectral density. Movement vigor was calculated at both body locations from the signal variance. Partial Spearman correlations between gait parameters and physiological fall risk factors (components from the Physiological Profile Assessment) were calculated while controlling for age and gender. Overall, anteroposterior vigor at the lower back in stair descent was lower in subjects with longer reaction times. Older adults walked more slowly on stairs, but they were not significantly slower on flat surfaces. Using logistic regression, faster step rate in stair descent was associated with multiple prospective falls over 12 months. No significant associations were shown from gait parameters derived during walking upstairs or on flat surfaces. These results suggest that stair descent gait may provide more insight into fall risk than regular walking and stair ascent, and that further sensor-based investigation into unsupervised gait on different terrains would be valuable.

Effects of multiple acute stressors on the predator avoidance ability and physiology of juvenile Chinook salmon

USGS Publications Warehouse

Mesa, Matthew G.

1994-01-01

Northern squaw fish Ptychocheilus oregonensis are the predominant predators of juvenile Pacific salmonids Oncorhynchus spp. in the Columbia River, and their predation rates are greatest just below dams. Because juvenile salmonids are commonly subjected to multiple stressors at dams in the course of their seaward migration, high predation rates below dams may be due in part to an increase in the vulnerability of stressed fish. I conducted laboratory experiments to examine the predator avoidance ability and physiological stress responses of juvenile chinook salmon O. tshawytscha subjected to treatments (stressors) designed to simulate routine hatchery practices (multiple handlings) or dam passage (multiple agitations). Both stressors resulted in lethargic behavior in the fish, and agitation also caused disorieniation and occasional injury. When equal numbers of stressed and unstressed fish were exposed to northern squawfish for up to 1 h, significantly more stressed fish were eaten, but this effect was not evident during longer exposures. The lack of differential predation in trials lasting up to 24 h can be explained by the rapid development of schooling behavior in the prey, but other possibilities exist, such as changing ratios of stressed and unstressed prey over time. Concentrations of plasma cortisol, glucose, and lactate in fish subjected to multiple stressors were similar and sometimes cumulative, returned to prestress levels within 6-24 h, and correlated poorly with predator avoidance ability. My results suggest that juvenile salmonids are capable of avoiding predators within 1 h after being subjected to multiple acute stressors even though physiological homeostasis may be altered for up to 24 h. Therefore, because juvenile salmonids typically reside in lailrace areas for only a short time after dam passage, measures aimed at reducing physical stress or protecting them as they migrate through dam tailraces may help alleviate the relatively intense predation in these areas.

Investigation on maternal physiological and psychological factors of cheilopalatognathus.

PubMed

Ma, J; Zhao, W; Ma, R M; Li, X J; Wen, Z H; Liu, X F; Hu, W D; Zhang, C B

2013-01-01

Case-control study on mothers of cheilopalatognathus children was conducted, to investigate the maternal physiological and psychological factors for occurrence of cheilopalatognathus. One hundred ten mothers of cheilopalatognathus children who were scheduled for one-stage surgery were selected as a research group, and 110 mothers of normal children served as a normal control group at the same time. Trait Anxiety Inventory (T-AI), Life Events Scale (LES), Trait Coping Style Questionnaire (TCSQ), Type C Behavior Scale (CBS), adult Eysenck Personality Questionnaire (EPQ), and homemade general questionnaire survey were employed for the investigation. Compared with the control group, the scores for negative event tension value, anxiety, and depressive factors were higher in the study group (p < 0.05); while the scores for positive event tension value, intellect, optimism, and social support factors were lower (p < 0.05). Regression analysis found that physiological factors included were five: education, changes in body weight during pregnancy, the intake amount of milk and beans, and intake of healthcare products, and supplementary folic acid taken or not, while the psychological factors included were four: positive event stimulation, negative event stimulation, the amount of social support, as well as introvert and extrovert personalities. The study results suggest that pregnant women's physiological and psychological factors can cause changes in cheilopalatognathus incidence, which is expected to be guidance for healthcare during pregnancy, to prevent the occurrence of cheilopalatognathus.

The Physiology and Biochemistry of Receptors.

ERIC Educational Resources Information Center

Spitzer, Judy A., Ed.

1983-01-01

The syllabus for a refresher course on the physiology and biochemistry of receptors (presented at the 1983 American Physiological Society meeting) is provided. Topics considered include receptor regulation, structural/functional aspects of receptors for insulin and insulin-like growth factors, calcium channel inhibitors, and role of lipoprotein…

Physiological responses to environmental factors related to space flight

NASA Technical Reports Server (NTRS)

Pace, N.

1972-01-01

The research is reported for establishing physiological base line data, and for developing procedures and instrumentation necessary for the automatic measurement of hemodynamic and metabolic parameters. The work in the following areas is discussed: biochemistry, bioinstrumentation, nutrition, physiology, experimental surgery, and animal colony.

Research report on the physiological effects of air ions and their significance as environmental factors

NASA Technical Reports Server (NTRS)

Varga, A.

1978-01-01

The series of experiments performed have shown that small air ions generated artificially using radioactive materials produced physiological effects in all test subjects, which are described. These results show that the air ions were important climatic factors in the production of comfortable and healthy room climates.

An Evaluation of Gestational Exposure to Perfluorooctanoic Acid (PFOA): Effects on Body Composition and Physiological Factors

EPA Science Inventory

Exposure to environmental pollutants can be a factor for induction of metabolic disorders. This study examined if exposure to PFOA during development could alter body composition and other physiological outcomes. Study 1: Pregnant CD-1 mice were gavaged with PFOA at 0,0.001,0.01,...

Relationship of aerobic and anaerobic parameters with 400 m front crawl swimming performance

PubMed Central

Kalva-Filho, CA; Campos, EZ; Andrade, VL; Silva, ASR; Zagatto, AM; Lima, MCS

2015-01-01

The aims of the present study were to investigate the relationship of aerobic and anaerobic parameters with 400 m performance, and establish which variable better explains long distance performance in swimming. Twenty-two swimmers (19.1±1.5 years, height 173.9±10.0 cm, body mass 71.2±10.2 kg; 76.6±5.3% of 400 m world record) underwent a lactate minimum test to determine lactate minimum speed (LMS) (i.e., aerobic capacity index). Moreover, the swimmers performed a 400 m maximal effort to determine mean speed (S400m), peak oxygen uptake (V.O2PEAK) and total anaerobic contribution (CANA). The CANA was assumed as the sum of alactic and lactic contributions. Physiological parameters of 400 m were determined using the backward extrapolation technique (V.O2PEAK and alactic contributions of CANA) and blood lactate concentration analysis (lactic anaerobic contributions of CANA). The Pearson correlation test and backward multiple regression analysis were used to verify the possible correlations between the physiological indices (predictor factors) and S400m (independent variable) (p < 0.05). Values are presented as mean ± standard deviation. Significant correlations were observed between S400m (1.4±0.1 m·s-1) and LMS (1.3±0.1 m·s-1; r = 0.80), V.O2PEAK (4.5±3.9 L·min-1; r = 0.72) and CANA (4.7±1.5 L·O2; r= 0.44). The best model constructed using multiple regression analysis demonstrated that LMS and V.O2PEAK explained 85% of the 400 m performance variance. When backward multiple regression analysis was performed, CANA lost significance. Thus, the results demonstrated that both aerobic parameters (capacity and power) can be used to predict 400 m swimming performance. PMID:28479663

The role of multiple-scale modelling of epilepsy in seizure forecasting

PubMed Central

Kuhlmann, Levin; Grayden, David B.; Wendling, Fabrice; Schiff, Steven J.

2014-01-01

Over the past three decades, a number of seizure prediction, or forecasting, methods have been developed. Although major achievements were accomplished regarding the statistical evaluation of proposed algorithms, it is recognized that further progress is still necessary for clinical application in patients. The lack of physiological motivation can partly explain this limitation. Therefore, a natural question is raised: can computational models of epilepsy be used to improve these methods? Here we review the literature on the multiple-scale neural modelling of epilepsy and the use of such models to infer physiological changes underlying epilepsy and epileptic seizures. We argue how these methods can be applied to advance the state-of-the-art in seizure forecasting. PMID:26035674

Advanced integrated real-time clinical displays.

PubMed

Kruger, Grant H; Tremper, Kevin K

2011-09-01

Intelligent medical displays have the potential to improve patient outcomes by integrating multiple physiologic signals, exhibiting high sensitivity and specificity, and reducing information overload for physicians. Research findings have suggested that information overload and distractions caused by patient care activities and alarms generated by multiple monitors in acute care situations, such as the operating room and the intensive care unit, may produce situations that negatively impact the outcomes of patients under anesthesia. This can be attributed to shortcomings of human-in-the-loop monitoring and the poor specificity of existing physiologic alarms. Modern artificial intelligence techniques (ie, intelligent software agents) are demonstrating the potential to meet the challenges of next-generation patient monitoring and alerting. Copyright © 2011 Elsevier Inc. All rights reserved.

Microglial Fc Receptors Mediate Physiological Changes Resulting From Antibody Cross-Linking of Myelin Oligodendrocyte Glycoprotein

PubMed Central

Marta, Cecilia B.; Bansal, Rashmi; Pfeiffer, Steven E.

2009-01-01

Antibodies to myelin oligodendrocyte glycoprotein (MOG) have been implicated in Multiple Sclerosis demyelination through activation of complement and/or macrophage-effector processes. We presented a novel mechanism, whereby MOG on oligodendrocytes, when cross-linked with anti-MOG and secondary antibody resulted in its repartitioning into lipid rafts, and changes in protein phosphorylation and morphology. Here, we show that similar events occur when anti-MOG is cross-linked with Fc receptors (FcRs) present on microglia but not with complement. These results indicate that FcRs are endogenous antigen/antibody cross-linkers in vitro, suggesting that FcRs could be physiologically relevant in vivo and possible targets for therapy in Multiple Sclerosis. PMID:18406472

Insomnia, metabolic rate and sleep restoration.

PubMed

Bonnet, M H; Arand, D L

2003-07-01

Studies have shown occasional evidence of increased physiological activity in patients with primary insomnia. We hypothesized that metabolic rate, as measured by overall oxygen use (VO2), might be a more general index of increased physiological activity. An initial experiment found elevated VO2 both at night and during the day in patients with primary insomnia as compared with matched normal sleepers. A second experiment found significant but more modest increases in VO2 in patients with Sleep State Misperception Insomnia [who complain of poor sleep but who had normal sleep by electroencephalographic (EEG) criteria]. In a third experiment, normal young adults were given caffeine 400 mg three times per day (TID) for 1 week as a means of increasing VO2 and possibly producing other symptoms of insomnia. Participants developed many symptoms consistent with those seen in patients with primary insomnia (poor sleep, increased latency on the Multiple Sleep Latency Test, increasing fatigue despite physiological activation, and increased anxiety on the Minnesota Multiphasic Personality Inventory (MMPI)). In a final experiment, physiological arousal was again produced by caffeine to determine if sleep with elevated arousal would be less restorative. All subjects (Ss) slept for 3.5 h after being given 400 mg of caffeine. During 41 h of sleep deprivation that followed, there was no significant condition difference for the Multiple Sleep Latency Test or mood measures. The results provided only weak support for the idea that sleep is less restorative after physiological arousal.

You can't take it with you? Effects of handheld portable media consoles on physiological and psychological responses to video game and movie content.

PubMed

Ivory, James D; Magee, Robert G

2009-06-01

Portable media consoles are becoming extremely popular devices for viewing a number of different types of media content, both for entertainment and for educational purposes. Given the increasingly heavy use of portable consoles as an alternative to traditional television-style monitors, it is important to investigate how physiological and psychological effects of portable consoles may differ from those of television-based consoles, because such differences in physiological and psychological responses may precipitate differences in the delivered content's effectiveness. Because portable consoles are popular as a delivery system for multiple types of media content, such as movies and video games, it is also important to investigate whether differences between the effects of portable and television-based consoles are consistent across multiple types of media. This article reports a 2 x 2 (console: portable or television-based x medium: video game or movie) mixed factorial design experiment with physiological arousal and self-reported flow experience as dependent variables, designed to explore whether console type affects media experiences and whether these effects are consistent across different media. Results indicate that portable media consoles evoke lower levels of physiological arousal and flow experience and that this effect is consistent for both video games and movies. These findings suggest that even though portable media consoles are often convenient compared to television-based consoles, the convenience may come at a cost in terms of the user experience.

Endurance exercise performance: the physiology of champions

PubMed Central

Joyner, Michael J; Coyle, Edward F

2008-01-01

Efforts to understand human physiology through the study of champion athletes and record performances have been ongoing for about a century. For endurance sports three main factors – maximal oxygen consumption , the so-called ‘lactate threshold’ and efficiency (i.e. the oxygen cost to generate a give running speed or cycling power output) – appear to play key roles in endurance performance. and lactate threshold interact to determine the ‘performance ‘ which is the oxygen consumption that can be sustained for a given period of time. Efficiency interacts with the performance to establish the speed or power that can be generated at this oxygen consumption. This review focuses on what is currently known about how these factors interact, their utility as predictors of elite performance, and areas where there is relatively less information to guide current thinking. In this context, definitive ideas about the physiological determinants of running and cycling efficiency is relatively lacking in comparison with and the lactate threshold, and there is surprisingly limited and clear information about the genetic factors that might pre-dispose for elite performance. It should also be cautioned that complex motivational and sociological factors also play important roles in who does or does not become a champion and these factors go far beyond simple physiological explanations. Therefore, the performance of elite athletes is likely to defy the types of easy explanations sought by scientific reductionism and remain an important puzzle for those interested in physiological integration well into the future. PMID:17901124

MADS-box transcription factor AGL21 regulates lateral root development and responds to multiple external and physiological signals.

PubMed

Yu, Lin-Hui; Miao, Zi-Qing; Qi, Guo-Feng; Wu, Jie; Cai, Xiao-Teng; Mao, Jie-Li; Xiang, Cheng-Bin

2014-11-01

Plant root system morphology is dramatically influenced by various environmental cues. The adaptation of root system architecture to environmental constraints, which mostly depends on the formation and growth of lateral roots, is an important agronomic trait. Lateral root development is regulated by the external signals coordinating closely with intrinsic signaling pathways. MADS-box transcription factors are known key regulators of the transition to flowering and flower development. However, their functions in root development are still poorly understood. Here we report that AGL21, an AGL17-clade MADS-box gene, plays a crucial role in lateral root development. AGL21 was highly expressed in root, particularly in the root central cylinder and lateral root primordia. AGL21 overexpression plants produced more and longer lateral roots while agl21 mutants showed impaired lateral root development, especially under nitrogen-deficient conditions. AGL21 was induced by many plant hormones and environmental stresses, suggesting a function of this gene in root system plasticity in response to various signals. Furthermore, AGL21 was found positively regulating auxin accumulation in lateral root primordia and lateral roots by enhancing local auxin biosynthesis, thus stimulating lateral root initiation and growth. We propose that AGL21 may be involved in various environmental and physiological signals-mediated lateral root development and growth. © The Author 2014. Published by Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

Microbial Changes during Pregnancy, Birth, and Infancy

PubMed Central

Nuriel-Ohayon, Meital; Neuman, Hadar; Koren, Omry

2016-01-01

Several healthy developmental processes such as pregnancy, fetal development, and infant development include a multitude of physiological changes: weight gain, hormonal, and metabolic changes, as well as immune changes. In this review, we present an additional important factor which both influences and is affected by these physiological processes—the microbiome. We summarize the known changes in microbiota composition at a variety of body sites including gut, vagina, oral cavity, and placenta, throughout pregnancy, fetal development, and early childhood. There is still a lot to be discovered; yet several pieces of research point to the healthy desired microbial changes. Future research is likely to unravel precise roles and mechanisms of the microbiota in gestation; perhaps linking the metabolic, hormonal, and immune changes together. Although some research has started to link microbial dysbiosis and specific microbial populations with unhealthy pregnancy complications, it is important to first understand the context of the natural healthy microbial changes occurring. Until recently the placenta and developing fetus were considered to be germ free, containing no apparent microbiome. We present multiple study results showing distinct microbiota compositions in the placenta and meconium, alluding to early microbial colonization. These results may change dogmas and our overall understanding of the importance and roles of microbiota from the beginning of life. We further review the main factors shaping the infant microbiome—modes of delivery, feeding, weaning, and exposure to antibiotics. Taken together, we are starting to build a broader understanding of healthy vs. abnormal microbial alterations throughout major developmental time-points. PMID:27471494

Phenotyping of subjects for large scale studies on patients with IBS.

PubMed

Boeckxstaens, G E; Drug, V; Dumitrascu, D; Farmer, A D; Hammer, J; Hausken, T; Niesler, B; Pohl, D; Pojskic, L; Polster, A; Simren, M; Goebel-Stengel, M; Van Oudenhove, L; Vassallo, M; Wensaas, K-A; Aziz, Q; Houghton, L A

2016-08-01

Irritable bowel syndrome (IBS) is a complex condition with multiple factors contributing to its aetiology and pathophysiology. Aetiologically these include genetics, life-time events and environment, and physiologically, changes in motility, central processing, visceral sensitivity, immunity, epithelial permeability and gastrointestinal microflora. Such complexity means there is currently no specific reliable biomarker for IBS, and thus IBS continues to be diagnosed and classified according to symptom based criteria, the Rome Criteria. Carefully phenotyping and characterisation of a 'large' pool of IBS patients across Europe and even the world however, might help identify sub-populations with accuracy and consistency. This will not only aid future research but improve tailoring of treatment and health care of IBS patients. The aim of this position paper is to discuss the requirements necessary to standardize the process of selecting and phenotyping IBS patients and how to organise the collection and storage of patient information/samples in such a large multi-centre pan European/global study. We include information on general demographics, gastrointestinal symptom assessment, psychological factors, quality of life, physiological evaluation, genetic/epigenetic and microbiota analysis, biopsy/blood sampling, together with discussion on the organisational, ethical and language issues associated with implementing such a study. The proposed approach and documents selected to be used in such a study was the result of a thoughtful and thorough four-year dialogue amongst experts associated with the European COST action BM1106 GENIEUR (www.GENIEUR.eu). © 2016 John Wiley & Sons Ltd.

Apology isn't good enough: an apology suppresses an approach motivation but not the physiological and psychological anger.

PubMed

Kubo, Kenta; Okanoya, Kazuo; Kawai, Nobuyuki

2012-01-01

Although studies have emphasized the multiple components of anger, little is known about the physiological and psychological mechanisms of the approach motivational component and the negative emotional component of anger. In the present study, participants wrote brief opinions about social problems (e.g., tuition hikes) and received a handwritten, insulting comment about their composition from the experimenter. Half of the participants (apology group) received a simple apologetic sentence at the end of the insulting comment. Half of the participants (no apology group) did not receive one. The physiological responses of the participants were recorded prior to, and after they read the comments. Increases in heart rate and asymmetric frontal brain activity were suppressed only in the apology group. Both groups showed an increase in skin conductance response. Our psychological scales showed that the apology suppressed self reported state anger from an approach-motivational standpoint but not from a negative emotional standpoint. The results suggest that anger is not a unitary process but has multiple components. The apology did provide a different physiological profile but did not dampen down the subjective experience of anger. Thus, providing an apology may not always be effective for alleviating the experience of anger to an insult.

Apology Isn't Good Enough: An Apology Suppresses an Approach Motivation but Not the Physiological and Psychological Anger

PubMed Central

Kubo, Kenta; Okanoya, Kazuo; Kawai, Nobuyuki

2012-01-01

Although studies have emphasized the multiple components of anger, little is known about the physiological and psychological mechanisms of the approach motivational component and the negative emotional component of anger. In the present study, participants wrote brief opinions about social problems (e.g., tuition hikes) and received a handwritten, insulting comment about their composition from the experimenter. Half of the participants (apology group) received a simple apologetic sentence at the end of the insulting comment. Half of the participants (no apology group) did not receive one. The physiological responses of the participants were recorded prior to, and after they read the comments. Increases in heart rate and asymmetric frontal brain activity were suppressed only in the apology group. Both groups showed an increase in skin conductance response. Our psychological scales showed that the apology suppressed self reported state anger from an approach-motivational standpoint but not from a negative emotional standpoint. The results suggest that anger is not a unitary process but has multiple components. The apology did provide a different physiological profile but did not dampen down the subjective experience of anger. Thus, providing an apology may not always be effective for alleviating the experience of anger to an insult. PMID:22457729

Basking behavior predicts the evolution of heat tolerance in Australian rainforest lizards.

PubMed

Muñoz, Martha M; Langham, Gary M; Brandley, Matthew C; Rosauer, Dan F; Williams, Stephen E; Moritz, Craig

2016-11-01

There is pressing urgency to understand how tropical ectotherms can behaviorally and physiologically respond to climate warming. We examine how basking behavior and thermal environment interact to influence evolutionary variation in thermal physiology of multiple species of lygosomine rainforest skinks from the Wet Tropics of northeastern Queensland, Australia (AWT). These tropical lizards are behaviorally specialized to exploit canopy or sun, and are distributed across marked thermal clines in the AWT. Using phylogenetic analyses, we demonstrate that physiological parameters are either associated with changes in local thermal habitat or to basking behavior, but not both. Cold tolerance, the optimal sprint speed, and performance breadth are primarily influenced by local thermal environment. Specifically, montane lizards are more cool tolerant, have broader performance breadths, and higher optimum sprinting temperatures than their lowland counterparts. Heat tolerance, in contrast, is strongly affected by basking behavior: there are two evolutionary optima, with basking species having considerably higher heat tolerance than shade skinks, with no effect of elevation. These distinct responses among traits indicate the multiple selective pressures and constraints that shape the evolution of thermal performance. We discuss how behavior and physiology interact to shape organisms' vulnerability and potential resilience to climate change. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Deadly diving? Physiological and behavioural management of decompression stress in diving mammals

PubMed Central

Hooker, S. K.; Fahlman, A.; Moore, M. J.; Aguilar de Soto, N.; Bernaldo de Quirós, Y.; Brubakk, A. O.; Costa, D. P.; Costidis, A. M.; Dennison, S.; Falke, K. J.; Fernandez, A.; Ferrigno, M.; Fitz-Clarke, J. R.; Garner, M. M.; Houser, D. S.; Jepson, P. D.; Ketten, D. R.; Kvadsheim, P. H.; Madsen, P. T.; Pollock, N. W.; Rotstein, D. S.; Rowles, T. K.; Simmons, S. E.; Van Bonn, W.; Weathersby, P. K.; Weise, M. J.; Williams, T. M.; Tyack, P. L.

2012-01-01

Decompression sickness (DCS; ‘the bends’) is a disease associated with gas uptake at pressure. The basic pathology and cause are relatively well known to human divers. Breath-hold diving marine mammals were thought to be relatively immune to DCS owing to multiple anatomical, physiological and behavioural adaptations that reduce nitrogen gas (N2) loading during dives. However, recent observations have shown that gas bubbles may form and tissue injury may occur in marine mammals under certain circumstances. Gas kinetic models based on measured time-depth profiles further suggest the potential occurrence of high blood and tissue N2 tensions. We review evidence for gas-bubble incidence in marine mammal tissues and discuss the theory behind gas loading and bubble formation. We suggest that diving mammals vary their physiological responses according to multiple stressors, and that the perspective on marine mammal diving physiology should change from simply minimizing N2 loading to management of the N2 load. This suggests several avenues for further study, ranging from the effects of gas bubbles at molecular, cellular and organ function levels, to comparative studies relating the presence/absence of gas bubbles to diving behaviour. Technological advances in imaging and remote instrumentation are likely to advance this field in coming years. PMID:22189402

Impact of Nutrition and Salinity Changes on Biological Performances of Green and White Sturgeon

PubMed Central

Vaz, Pedro G.; Kebreab, Ermias; Hung, Silas S. O.; Fadel, James G.; Lee, Seunghyung; Fangue, Nann A.

2015-01-01

Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate current environmental changes. Through nutrition and salinity challenges, climate change will likely have more physiological effect on young sturgeon stages, which in turn may affect growth performance. In this study, the two species were challenged in a multiple-factor experimental setting, first to levels of feeding rate, and then to salinity levels for different time periods. Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables. Using structural equation modeling, a path diagram is proposed to quantify the main linkages among nutrition status, salinity, osmoregulation variables, and growth performances. Three major trends were anticipated for the growth performance of green and white sturgeon in the juvenile stage in the SFBD: (i) a decrease in prey abundance will be highly detrimental for the growth of both species; (ii) an acute increase in salinity within the limits studied can be tolerated by both species but possibly the energy spent in osmoregulation may affect green sturgeon growth within the time window assessed; (iii) the mechanism of synergistic effects of nutrition and salinity changes will be more complex in green sturgeon, with condition factor responding nonlinearly to interactions of salinity and nutrition status or time of salinity exposure. Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the SFBD. PMID:25830227

Impact of nutrition and salinity changes on biological performances of green and white sturgeon.

PubMed

Vaz, Pedro G; Kebreab, Ermias; Hung, Silas S O; Fadel, James G; Lee, Seunghyung; Fangue, Nann A

2015-01-01

Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate current environmental changes. Through nutrition and salinity challenges, climate change will likely have more physiological effect on young sturgeon stages, which in turn may affect growth performance. In this study, the two species were challenged in a multiple-factor experimental setting, first to levels of feeding rate, and then to salinity levels for different time periods. Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables. Using structural equation modeling, a path diagram is proposed to quantify the main linkages among nutrition status, salinity, osmoregulation variables, and growth performances. Three major trends were anticipated for the growth performance of green and white sturgeon in the juvenile stage in the SFBD: (i) a decrease in prey abundance will be highly detrimental for the growth of both species; (ii) an acute increase in salinity within the limits studied can be tolerated by both species but possibly the energy spent in osmoregulation may affect green sturgeon growth within the time window assessed; (iii) the mechanism of synergistic effects of nutrition and salinity changes will be more complex in green sturgeon, with condition factor responding nonlinearly to interactions of salinity and nutrition status or time of salinity exposure. Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the SFBD.

Form Factor Evaluation of Open Body Area Network (OBAN) Physiological Status Monitoring (PSM) System Prototype Designs

DTIC Science & Technology

2018-05-11

SYSTEM PROTOTYPE DESIGNS DISCLAIMERS The opinions or assertions contained herein are the private views of the author(s) and are not to be construed as...FORM FACTOR EVALUATION OF OPEN BODY AREA NETWORK (OBAN) PHYSIOLOGICAL STATUS MONITORING (PSM) SYSTEM PROTOTYPE DESIGNS William J...security; and is designed to function for 72 hours or more. The test described in this report assesses proposed form-factor designs . Feedback using

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

Interaction between parathyroid hormone and endogenous estrogen in normal women.

PubMed

Buchanan, J R; Santen, R J; Cavaliere, A; Cauffman, S W; Greer, R B; Demers, L M

1986-06-01

It has been hypothesized that estrogens conserve bone substance by blocking the resorbing effect of parathyroid hormone (PTH). We evaluated this hypothesis by examining the relation of circulating PTH to endogenous estrogen fluctuation during four quarters of a single menstrual cycle in 20 normal women. The hypothesis predicts that PTH should vary directly with estrogen, since PTH should increase following estrogen elevation to satisfy physiologic demands for calcium. Contrary to the predicted direct variation, PTH remained constant throughout the menstrual cycle despite sharply fluctuating estrogen levels. Furthermore, PTH was negatively associated with estrone during the early follicular (r = -.65, P less than 0.005) and late follicular (r = -.84, P less than 0.0001) phases. We attempted to determine whether this unexpected relationship between estrone and PTH signified a direct physiologic link, by excluding factors which could have spuriously engendered the inverse correlation. Stepwise multiple regression and partial correlation showed that estrone contributed significantly to circulating PTH independent of the effects of dietary calcium, 25-hydroxyvitamin D, serum calcium, 1,25-dihydroxyvitamin D, phosphate, estradiol, progesterone, and body weight. Therefore, it is possible that the inverse correlation between estrone and PTH signified a direct physiologic link, as an artifactual cause for the relationship could not be identified. These data imply that estrone interacts with PTH, but not by blocking PTH-mediated bone resorption. We conclude that estrone is associated with reduced circulating PTH through an as yet undetermined mechanism.

The physiological basis of complementary and alternative medicines for polycystic ovary syndrome.

PubMed

Raja-Khan, Nazia; Stener-Victorin, Elisabet; Wu, XiaoKe; Legro, Richard S

2011-07-01

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that is characterized by chronic hyperandrogenic anovulation leading to symptoms of hirsutism, acne, irregular menses, and infertility. Multiple metabolic and cardiovascular risk factors are associated with PCOS, including insulin resistance, obesity, type 2 diabetes, hypertension, inflammation, and subclinical atherosclerosis. However, current treatments for PCOS are only moderately effective at controlling symptoms and preventing complications. This article describes how the physiological effects of major complementary and alternative medicine (CAM) treatments could reduce the severity of PCOS and its complications. Acupuncture reduces hyperandrogenism and improves menstrual frequency in PCOS. Acupuncture's clinical effects are mediated via activation of somatic afferent nerves innervating the skin and muscle, which, via modulation of the activity in the somatic and autonomic nervous system, may modulate endocrine and metabolic functions in PCOS. Chinese herbal medicines and dietary supplements may also exert beneficial physiological effects in PCOS, but there is minimal evidence that these CAM treatments are safe and effective. Mindfulness has not been investigated in PCOS, but it has been shown to reduce psychological distress and exert positive effects on the central and autonomic nervous systems, hypothalamic-pituitary-adrenal axis, and immune system, leading to reductions in blood pressure, glucose, and inflammation. In conclusion, CAM treatments may have beneficial endocrine, cardiometabolic, and reproductive effects in PCOS. However, most studies of CAM treatments for PCOS are small, nonrandomized, or uncontrolled. Future well-designed studies are needed to further evaluate the safety, effectiveness, and mechanisms of CAM treatments for PCOS.

The influence of dissolved oxygen on winter habitat selection by largemouth bass: an integration of field biotelemetry studies and laboratory experiments.

PubMed

Hasler, C T; Suski, C D; Hanson, K C; Cooke, S J; Tufts, B L

2009-01-01

In this study, field biotelemetry and laboratory physiology approaches were coupled to allow understanding of the behavioral and physiological responses of fish to winter hypoxia. The biotelemetry study compared dissolved oxygen levels measured throughout the winter period with continually tracked locations of nine adult largemouth bass obtained from a whole-lake submerged telemetry array. Fish habitat usage was compared with habitat availability to assess whether fish were selecting for specific dissolved oxygen concentrations. The laboratory study examined behavioral and physiological responses to progressive hypoxia in juvenile largemouth bass acclimated to winter temperatures. Results from the dissolved oxygen measurements made during the biotelemetry study showed high variance in under-ice dissolved oxygen levels. Avoidance of water with dissolved oxygen <2.0 mg/L by telemetered fish was demonstrated, but significant use of water with intermediate dissolved oxygen levels was also found. Results from the lab experiments showed marked changes in behavior (i.e., yawning and vertical movement) at <2.0 mg/L of dissolved oxygen but no change in tissue lactate, an indicator of anaerobic metabolism. Combined results of the biotelemetry and laboratory studies demonstrate that a dissolved oxygen content of 2.0 mg/L may be a critical threshold that induces behavioral responses by largemouth bass during the winter. In addition, the use by fish of areas with intermediate levels of dissolved oxygen suggests that there are multiple environmental factors influencing winter behavior.

Flipped classroom model improves graduate student performance in cardiovascular, respiratory, and renal physiology.

PubMed

Tune, Johnathan D; Sturek, Michael; Basile, David P

2013-12-01

The purpose of this study was to assess the effectiveness of a traditional lecture-based curriculum versus a modified "flipped classroom" curriculum of cardiovascular, respiratory, and renal physiology delivered to first-year graduate students. Students in both courses were provided the same notes and recorded lectures. Students in the modified flipped classroom were required to watch the prerecorded lectures before class and then attend class, where they received a quiz or homework covering material in each lecture (valued at 25% of the final grade) followed by a question and answer/problem-solving period. In the traditional curriculum, attending lectures was optional and there were no quizzes. Evaluation of effectiveness and student performance was achieved by having students in both courses take the same multiple-choice exams. Within a comparable group of graduate students, participants in the flipped course scored significantly higher (P ≤ 0.05) on the cardiovascular, respiratory, and weighted cumulative sections by an average of >12 percentage points. Exam averages for students in the flipped course also tended to be higher on the renal section by ∼11 percentage points (P = 0.06). Based on our experience and responses obtained in blinded student surveys, we propose that the use of homework and in-class quizzes were critical motivating factors that likely contributed to the increase in student exam performance. Taken together, our findings support that the flipped classroom model is a highly effective means in which to disseminate key physiological concepts to graduate students.

Impact of ocean acidification on the hypoxia tolerance of the woolly sculpin, Clinocottus analis.

PubMed

Hancock, Joshua R; Place, Sean P

2016-01-01

As we move into the Anthropocene, organisms inhabiting marine environments will continue to face growing challenges associated with changes in ocean pH (ocean acidification), dissolved oxygen (dead zones) and temperature. These factors, in combination with naturally variable environments such as the rocky intertidal zone, may create extreme physiological challenges for organisms that are already performing near their biological limits. Although numerous studies have examined the impacts of climate-related stressors on intertidal animals, little is known about the underlying physiological mechanisms driving adaptation to ocean acidification and how this may alter organism interactions, particularly in marine vertebrates. Therefore, we have investigated the effects of decreased ocean pH on the hypoxia response of an intertidal sculpin, Clinocottus analis . We used both whole-animal and biochemistry-based analyses to examine how the energetic demands associated with acclimation to low-pH environments may impact the fish's reliance on facultative air breathing in low-oxygen environments. Our study demonstrated that acclimation to ocean acidification resulted in elevated routine metabolic rates and acid-base regulatory capacity (Na + ,K + -ATPase activity). These, in turn, had downstream effects that resulted in decreased hypoxia tolerance (i.e. elevated critical oxygen tension). Furthermore, we present evidence that these fish may be living near their physiological capacity when challenged by ocean acidification. This serves as a reminder that the susceptibility of teleost fish to changes in ocean pH may be underestimated, particularly when considering the multiple stressors that many experience in their natural environments.

Psychoneurometric Operationalization of Threat Sensitivity: Relations with Clinical Symptom and Physiological Response Criteria

PubMed Central

Yancey, James R.; Venables, Noah C.; Patrick, Christopher J.

2015-01-01

The NIMH RDoC initiative calls for the incorporation of neurobiological approaches and findings into conceptions of mental health problems through a focus on biobehavioral constructs investigated across multiple domains of measurement (units of analysis). Though the constructs in the RDoC system are characterized in ‘process terms’ (i.e., as functional concepts with brain and behavioral referents), these constructs can also be framed as dispositions (i.e., as dimensions of variation in biobehavioral functioning across individuals). Focusing on one key RDoC construct, acute threat or ‘fear’, the current paper illustrates a construct-oriented psychoneurometric strategy to operationalizing this construct in individual-difference terms—as threat sensitivity (THT+). Utilizing data from 454 adult participants, we demonstrate empirically that: 1) a scale measure of THT+ design to tap general fear/fearlessness predicts effectively to relevant clinical problems (i.e., fear disorder symptoms), 2) this scale measure shows reliable associations with physiological indices of acute reactivity to aversive visual stimuli, and 3) a cross-domain factor reflecting the intersection of scale and physiological indicators of THT+ predicts effectively to both clinical and neurophysiological criterion measures. Results illustrate how the psychoneurometric approach can be used to create a dimensional index of a biobehavioral trait construct, in this case THT+, which can serve as a bridge between phenomena in domains of psychopathology and neurobiology. Implications and future directions are discussed with reference to the RDoC initiative and existing report-based conceptions of psycholological traits. PMID:26877132

Extracellular Matrix Reorganization During Wound Healing and Its Impact on Abnormal Scarring

PubMed Central

Xue, Meilang; Jackson, Christopher J.

2015-01-01

Significance: When a cutaneous injury occurs, the wound heals via a dynamic series of physiological events, including coagulation, granulation tissue formation, re-epithelialization, and extracellular matrix (ECM) remodeling. The final stage can take many months, yet the new ECM forms a scar that never achieves the flexibility or strength of the original tissue. In certain circumstances, the normal scar is replaced by pathological fibrotic tissue, which results in hypertrophic or keloid scars. These scars cause significant morbidity through physical dysfunction and psychological stress. Recent Advances and Critical Issues: The cutaneous ECM comprises a complex assortment of proteins that was traditionally thought to simply provide structural integrity and scaffolding characteristics. However, recent findings show that the ECM has multiple functions, including, storage and delivery of growth factors and cytokines, tissue repair and various physiological functions. Abnormal ECM reconstruction during wound healing contributes to the formation of hypertrophic and keloid scars. Whereas adult wounds heal with scarring, the developing foetus has the ability to heal wounds in a scarless fashion by regenerating skin and restoring the normal ECM architecture, strength, and function. Recent studies show that the lack of inflammation in fetal wounds contributes to this perfect healing. Future Directions: Better understanding of the exact roles of ECM components in scarring will allow us to produce therapeutic agents to prevent hypertrophic and keloid scars. This review will focus on the components of the ECM and their role in both physiological and pathological (hypertrophic and keloid) cutaneous scar formation. PMID:25785236

Psychosocial stress in pregnancy and preterm birth: associations and mechanisms

PubMed Central

Shapiro, Gabriel D.; Fraser, William D.; Frasch, Martin G.; Séguin, Jean R.

2016-01-01

Aims Psychosocial stress during pregnancy (PSP) is a risk factor of growing interest in the etiology of preterm birth (PTB). This literature review assesses the published evidence concerning the association between PSP and PTB, highlighting established and hypothesized physiological pathways mediating this association. Method The PubMed and Web of Science databases were searched using the keywords “psychosocial stress”, “pregnancy”, “pregnancy stress”, “preterm”, “preterm birth”, “gestational age”, “anxiety”, and “social support”. After applying the exclusion criteria, the search produced 107 articles. Results The association of PSP with PTB varied according to the dimensions and timing of PSP. Stronger associations were generally found in early pregnancy, and most studies demonstrating positive results found moderate effect sizes, with risk ratios between 1.2 and 2.1. Subjective perception of stress and pregnancy-related anxiety appeared to be the stress measures most closely associated with PTB. Potential physiological pathways identified included behavioral, infectious, neuroinflammatory, and neuroendocrine mechanisms. Conclusions Future research should examine the biological pathways of these different psychosocial stress dimensions and at multiple time points across pregnancy. Culture-independent characterization of the vaginal microbiome and noninvasive monitoring of cholinergic activity represent two exciting frontiers in this research. PMID:24216160

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.

Functional dyspepsia

PubMed Central

Brun, Rita; Kuo, Braden

2010-01-01

Dyspepsia is a common term used for a heterogeneous group of abdominal symptoms. Functional dyspepsia (FD) is the focus of this review. The 2006 Rome III criteria defined FD and its subgroups, postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). FD is a very common condition with a high prevalence throughout the world, adversely affecting the quality of life of patients. The pathophysiology of FD has been under investigation during the past two decades. Multiple mechanisms such as abnormal gastric emptying, visceral hypersensitivity, impaired gastric accommodation, and central nervous system factors are likely involved. Several tests are available for the assessment of various physiologic functions possibly involved in the pathogenesis of FD, and some of these could be used in clinical practice, helping to understand the abnormalities underlining patients’ complaints. Currently, the possibilities of pharmacological therapy for FD are still limited, however, experience of using prokinetics, tricyclic antidepressants, selective serotonin-reuptake inhibitors (SSRIs), proton-pump inhibitors (PPIs), and several alternative techniques has been accumulated. The different combinations of alterations in physiologic gastrointestinal and central nervous system functions result in the very heterogeneous nature of FD so combined approaches to these patients could be beneficial in challenging cases. PMID:21180597

Sublethal salinity stress contributes to habitat limitation in an endangered estuarine fish.

PubMed

Komoroske, Lisa M; Jeffries, Ken M; Connon, Richard E; Dexter, Jason; Hasenbein, Matthias; Verhille, Christine; Fangue, Nann A

2016-09-01

As global change alters multiple environmental conditions, predicting species' responses can be challenging without understanding how each environmental factor influences organismal performance. Approaches quantifying mechanistic relationships can greatly complement correlative field data, strengthening our abilities to forecast global change impacts. Substantial salinity increases are projected in the San Francisco Estuary, California, due to anthropogenic water diversion and climatic changes, where the critically endangered delta smelt (Hypomesus transpacificus) largely occurs in a low-salinity zone (LSZ), despite their ability to tolerate a much broader salinity range. In this study, we combined molecular and organismal measures to quantify the physiological mechanisms and sublethal responses involved in coping with salinity changes. Delta smelt utilize a suite of conserved molecular mechanisms to rapidly adjust their osmoregulatory physiology in response to salinity changes in estuarine environments. However, these responses can be energetically expensive, and delta smelt body condition was reduced at high salinities. Thus, acclimating to salinities outside the LSZ could impose energetic costs that constrain delta smelt's ability to exploit these habitats. By integrating data across biological levels, we provide key insight into the mechanistic relationships contributing to phenotypic plasticity and distribution limitations and advance the understanding of the molecular osmoregulatory responses in nonmodel estuarine fishes.

Hypercholesterolemia induces adipose dysfunction in conditions of obesity and nonobesity.

PubMed

Aguilar, David; Fernandez, Maria Luz

2014-09-01

It is well known that hypercholesterolemia can lead to atherosclerosis and coronary heart disease. Adipose tissue represents an active endocrine and metabolic site, which might be involved in the development of chronic disease. Because adipose tissue is a key site for cholesterol metabolism and the presence of hypercholesterolemia has been shown to induce adipocyte cholesterol overload, it is critical to investigate the role of hypercholesterolemia on normal adipose function. Studies in preadipocytes revealed that cholesterol accumulation can impair adipocyte differentiation and maturation by affecting multiple transcription factors. Hypercholesterolemia has been observed to cause adipocyte hypertrophy, adipose tissue inflammation, and disruption of endocrine function in animal studies. Moreover, these effects can also be observed in obesity-independent conditions as confirmed by clinical trials. In humans, hypercholesterolemia disrupts adipose hormone secretion of visfatin, leptin, and adiponectin, adipokines that play a central role in numerous metabolic pathways and regulate basic physiologic responses such as appetite and satiety. Remarkably, treatment with cholesterol-lowering drugs has been shown to restore adipose tissue endocrine function. In this review the role of hypercholesterolemia on adipose tissue differentiation and maturation, as well as on hormone secretion and physiologic outcomes, in obesity and non–obesity conditions is presented.

A comprehensive prediction and evaluation method of pilot workload

PubMed Central

Feng, Chuanyan; Wanyan, Xiaoru; Yang, Kun; Zhuang, Damin; Wu, Xu

2018-01-01

BACKGROUND: The prediction and evaluation of pilot workload is a key problem in human factor airworthiness of cockpit. OBJECTIVE: A pilot traffic pattern task was designed in a flight simulation environment in order to carry out the pilot workload prediction and improve the evaluation method. METHODS: The prediction of typical flight subtasks and dynamic workloads (cruise, approach, and landing) were built up based on multiple resource theory, and a favorable validity was achieved by the correlation analysis verification between sensitive physiological data and the predicted value. RESULTS: Statistical analysis indicated that eye movement indices (fixation frequency, mean fixation time, saccade frequency, mean saccade time, and mean pupil diameter), Electrocardiogram indices (mean normal-to-normal interval and the ratio between low frequency and sum of low frequency and high frequency), and Electrodermal Activity indices (mean tonic and mean phasic) were all sensitive to typical workloads of subjects. CONCLUSION: A multinominal logistic regression model based on combination of physiological indices (fixation frequency, mean normal-to-normal interval, the ratio between low frequency and sum of low frequency and high frequency, and mean tonic) was constructed, and the discriminate accuracy was comparatively ideal with a rate of 84.85%. PMID:29710742

A comprehensive prediction and evaluation method of pilot workload.

PubMed

Feng, Chuanyan; Wanyan, Xiaoru; Yang, Kun; Zhuang, Damin; Wu, Xu

2018-01-01

The prediction and evaluation of pilot workload is a key problem in human factor airworthiness of cockpit. A pilot traffic pattern task was designed in a flight simulation environment in order to carry out the pilot workload prediction and improve the evaluation method. The prediction of typical flight subtasks and dynamic workloads (cruise, approach, and landing) were built up based on multiple resource theory, and a favorable validity was achieved by the correlation analysis verification between sensitive physiological data and the predicted value. Statistical analysis indicated that eye movement indices (fixation frequency, mean fixation time, saccade frequency, mean saccade time, and mean pupil diameter), Electrocardiogram indices (mean normal-to-normal interval and the ratio between low frequency and sum of low frequency and high frequency), and Electrodermal Activity indices (mean tonic and mean phasic) were all sensitive to typical workloads of subjects. A multinominal logistic regression model based on combination of physiological indices (fixation frequency, mean normal-to-normal interval, the ratio between low frequency and sum of low frequency and high frequency, and mean tonic) was constructed, and the discriminate accuracy was comparatively ideal with a rate of 84.85%.

Modeling and Measurement of Correlation between Blood and Interstitial Glucose Changes

PubMed Central

Shi, Ting; Li, Dachao; Li, Guoqing; Zhang, Yiming; Xu, Kexin; Lu, Luo

2016-01-01

One of the most effective methods for continuous blood glucose monitoring is to continuously measure glucose in the interstitial fluid (ISF). However, multiple physiological factors can modulate glucose concentrations and affect the lag phase between blood and ISF glucose changes. This study aims to develop a compensatory tool for measuring the delay in ISF glucose variations in reference to blood glucose changes. A theoretical model was developed based on biophysics and physiology of glucose transport in the microcirculation system. Blood and interstitial fluid glucose changes were measured in mice and rats by fluorescent and isotope methods, respectively. Computer simulation mimicked curves were fitted with data resulting from fluorescent measurements of mice and isotope measurements of rats, indicating that there were lag times for ISF glucose changes. It also showed that there was a required diffusion distance for glucose to travel from center of capillaries to interstitial space in both mouse and rat models. We conclude that it is feasible with the developed model to continuously monitor dynamic changes of blood glucose concentration through measuring glucose changes in ISF with high accuracy, which requires correct parameters for determining and compensating for the delay time of glucose changes in ISF. PMID:27239479

Violent video game effects on aggression, empathy, and prosocial behavior in eastern and western countries: a meta-analytic review.

PubMed

Anderson, Craig A; Shibuya, Akiko; Ihori, Nobuko; Swing, Edward L; Bushman, Brad J; Sakamoto, Akira; Rothstein, Hannah R; Saleem, Muniba

2010-03-01

Meta-analytic procedures were used to test the effects of violent video games on aggressive behavior, aggressive cognition, aggressive affect, physiological arousal, empathy/desensitization, and prosocial behavior. Unique features of this meta-analytic review include (a) more restrictive methodological quality inclusion criteria than in past meta-analyses; (b) cross-cultural comparisons; (c) longitudinal studies for all outcomes except physiological arousal; (d) conservative statistical controls; (e) multiple moderator analyses; and (f) sensitivity analyses. Social-cognitive models and cultural differences between Japan and Western countries were used to generate theory-based predictions. Meta-analyses yielded significant effects for all 6 outcome variables. The pattern of results for different outcomes and research designs (experimental, cross-sectional, longitudinal) fit theoretical predictions well. The evidence strongly suggests that exposure to violent video games is a causal risk factor for increased aggressive behavior, aggressive cognition, and aggressive affect and for decreased empathy and prosocial behavior. Moderator analyses revealed significant research design effects, weak evidence of cultural differences in susceptibility and type of measurement effects, and no evidence of sex differences in susceptibility. Results of various sensitivity analyses revealed these effects to be robust, with little evidence of selection (publication) bias.

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).

Renal Transport of Uric Acid: Evolving Concepts and Uncertainties

PubMed Central

Bobulescu, Ion Alexandru; Moe, Orson W.

2013-01-01

In addition to its role as a metabolic waste product, uric acid has been proposed to be an important molecule with multiple functions in human physiology and pathophysiology and may be linked to human diseases beyond nephrolithiasis and gout. Uric acid homeostasis is determined by the balance between production, intestinal secretion, and renal excretion. The kidney is an important regulator of circulating uric acid levels, by reabsorbing around 90% of filtered urate, while being responsible for 60–70% of total body uric acid excretion. Defective renal handling of urate is a frequent pathophysiologic factor underpinning hyperuricemia and gout. In spite of tremendous advances over the past decade, the molecular mechanisms of renal urate transport are still incompletely understood. Many transport proteins are candidate participants in urate handling, with URAT1 and GLUT9 being the best characterized to date. Understanding these transporters is increasingly important for the practicing clinician as new research unveils their physiology, importance in drug action, and genetic association with uric acid levels in human populations. The future may see the introduction of new drugs that specifically act on individual renal urate transporters for the treatment of hyperuricemia and gout. PMID:23089270

Multiple resistances against diseases and insects in a breeding population of pinus pinaster

Treesearch

Alejandr Solla; Maria Vivas; Elena Cubera; Luis Sampedro; Xoaquin Moreira; Esther Merlo; Raul de la Mata; Rafael Zas

2012-01-01

The different plant defenses existing within a given taxon have been commonly assumed to trade-off among each other because of both evolutionary and physiological reasons. The higher the efficiency of a single defensive trait, the lower selective pressure for other redundant defenses expected. On the other hand, production of multiple defenses might be...

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

PubMed Central

Kell, Douglas B

2009-01-01

Background The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. Review We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles. Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here. Conclusion Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets. PMID:19133145

A Summary of the Biological Basis of Frailty.

PubMed

Fielding, Roger A

2015-01-01

Frailty has been defined as a geriatric syndrome that is characterized by a reduction in the physiological reserve required for an individual to respond to endogenous and exogenous stressors. Using a discrete definition of frailty that includes sedentariness, involuntary weight loss, fatigue, poor muscle strength, and slow gait speed, 'frailty' has been associated with increased disability, postsurgical complications, and increased mortality. Despite the strong associations between frailty and subsequent poor outcomes, limited attention to this common geriatric condition has been paid in clinical settings. A more fundamental basic understanding of the biological factors that contribute to the frailty phenotype has begun to emerge. Multiple underlying biological factors such as dysregulation of inflammatory processes, genomic instability, oxidative stress, mitochondrial dysfunction, and cellular senescence appear to contribute to the clinical presentation of frailty. This chapter summarizes the papers presented on the biological basis of frailty from the 83rd Nestlé Nutrition Institute Workshop on 'Frailty, Pathophysiology, Phenotype and Patient Care' held in Barcelona, Spain, in March 2014. © 2015 Nestec Ltd., Vevey/S. Karger AG, Basel.

Crew factors in flight operations. Part 4: Sleep and wakefulness in international aircrews

NASA Technical Reports Server (NTRS)

Graeber, R. C.

1986-01-01

Physiological recordings of sleep and wakefulness in operating international (B-747) flight crews were obtained. Crews spent their first layover (48 h) of a trip in a sleep laboratory where standardized EEG, electro-oculograph (EOC), and electromyograph (EMG) sleep recordings were carried out whenever volunteers chose to sleep. During periods of wakefulness they underwent multiple sleep latency tests every 2 h in order to assess daytime drowsiness. The same standardized recordings were carried out at a home-based laboratory before departure. Approximately four crews each participated in flights over 7 to 9 time zones on five routes. All participants were encouraged to use whatever sleep-wake strategies they thought would provide them with the most satisfactory crew rest. Overall, layover sleep quality was not seriously disturbed, but eastward flights produced greater sleep disruption. The contributors of individual factors and the usefulness of various sleep strategies are discussed in the individual laboratory reports and in an operational summary.

The wheat transcription factor, TabHLH39, improves tolerance to multiple abiotic stressors in transgenic plants.

PubMed

Zhai, Yiqian; Zhang, Lichao; Xia, Chuan; Fu, Silu; Zhao, Guangyao; Jia, Jizeng; Kong, Xiuying

2016-05-13

Although bHLH transcription factors play important roles regulating plant development and abiotic stress response and tolerance, few functional studies have been performed in wheat. In this study, we isolated and characterized a bHLH gene, TabHLH39, from wheat. The TabHLH39 gene is located on wheat chromosome 5DL, and the protein localized to the nucleus and activated transcription. TabHLH39 showed variable expression in roots, stems, leaves, glumes, pistils and stamens and was induced by polyethylene glycol, salt and cold treatments. Further analysis revealed that TabHLH39 overexpression in Arabidopsis significantly enhanced tolerance to drought, salt and freezing stress during the seedling stage, which was also demonstrated by enhanced abiotic stress-response gene expression and changes to several physiological indices. Therefore, TabHLH39 has potential in transgenic breeding applications to improve abiotic stress tolerance in crops. Copyright © 2016 Elsevier Inc. All rights reserved.

RIP4 is a target of multiple signal transduction pathways in keratinocytes: Implications for epidermal differentiation and cutaneous wound repair

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

Adams, Stephanie; Munz, Barbara, E-mail: barbara.munz@charite.de

2010-01-01

Receptor interacting protein 4 (RIP4) is an important regulator of epidermal morphogenesis during embryonic development. We could previously show that expression of the rip4 gene is strongly downregulated in cutaneous wound repair, which might be initiated by a broad variety of growth factors and cytokines. Here, we demonstrate that in keratinocytes, rip4 expression is controlled by a multitude of different signal transduction pathways, such as the p38 mitogen-activated protein kinase (MAPK) and the nuclear factor kappa B (NF-{kappa}B) cascade, in a unique and specific manner. Furthermore, we show that the steroid dexamethasone abolishes the physiological rip4 downregulation after injury andmore » might thus contribute to the phenotype of reduced and delayed wound reepithelialization seen in glucocorticoid-treated patients. As a whole, our data indicate that rip4 expression is regulated in a complex manner, which might have therapeutic implications.« less

The Effect of Hypoxia on Mesenchymal Stem Cell Biology

PubMed Central

Ejtehadifar, Mostafa; Shamsasenjan, Karim; Movassaghpour, Aliakbar; Akbarzadehlaleh, Parvin; Dehdilani, Nima; Abbasi, Parvaneh; Molaeipour, Zahra; Saleh, Mahshid

2015-01-01

Although physiological and pathological role of hypoxia have been appreciated in mammalians for decades however the cellular biology of hypoxia more clarified in the past 20 years. Discovery of the transcription factor hypoxia-inducible factor (HIF)-1, in the 1990s opened a new window to investigate the mechanisms behind hypoxia. In different cellular contexts HIF-1 activation show variable results by impacting various aspects of cell biology such as cell cycle, apoptosis, differentiation and etc. Mesenchymal stem cells (MSC) are unique cells which take important role in tissue regeneration. They are characterized by self-renewal capacity, multilineage potential, and immunosuppressive property. Like so many kind of cells, hypoxia induces different responses in MSCs by HIF- 1 activation. The activation of this molecule changes the growth, multiplication, differentiation and gene expression profile of MSCs in their niche by a complex of signals. This article briefly discusses the most important effects of hypoxia in growth kinetics, signalling pathways, cytokine secretion profile and expression of chemokine receptors in different conditions. PMID:26236651

Is the Gut Microbiota a New Factor Contributing to Obesity and Its Metabolic Disorders?

PubMed Central

Harris, Kristina; Kassis, Amira; Major, Geneviève; Chou, Chieh J.

2012-01-01

The gut microbiota refers to the trillions of microorganisms residing in the intestine and is integral in multiple physiological processes of the host. Recent research has shown that gut bacteria play a role in metabolic disorders such as obesity, diabetes, and cardiovascular diseases. The mechanisms by which the gut microbiota affects metabolic diseases are by two major routes: (1) the innate immune response to the structural components of bacteria (e.g., lipopolysaccharide) resulting in inflammation and (2) bacterial metabolites of dietary compounds (e.g., SCFA from fiber), which have biological activities that regulate host functions. Gut microbiota has evolved with humans as a mutualistic partner, but dysbiosis in a form of altered gut metagenome and collected microbial activities, in combination with classic genetic and environmental factors, may promote the development of metabolic disorders. This paper reviews the available literature about the gut microbiota and aforementioned metabolic disorders and reveals the gaps in knowledge for future study. PMID:22315672

A multifaceted role for MOF histone modifying factor in genome maintenance

PubMed Central

Mujoo, Kalpana; Hunt, Clayton R.; Horikoshi, Nobuo; Pandita, Tej K.

2016-01-01

MOF (males absent on the first) was initially identified as a dosage compensation factor in Drosophila that acetylates lysine 16 of histone H4 (H4K16ac) and increased gene transcription from the single copy male X-chromosome. In humans, however, the ortholog of Drosophila MOF has been shown to interact with a range of proteins that extend its potential significance well beyond transcription. For example, recent results indicate MOF is an upstream regulator of the ATM (ataxia-telangiectasia mutated) protein, the loss of which is responsible for ataxia telangiectasia (AT). ATM is a key regulatory kinase that interacts with and phosphorylates multiple substrates that influence critical, cell-cycle control and DNA damage repair pathways in addition to other pathways. Thus, directly or indirectly, MOF may be involved in a wide range of cellular functions. This review will focus on the contribution of MOF to cellular DNA repair and new results that are beginning to examine the in vivo physiological role of MOF. PMID:27038808

Interplay between chemotaxis and contact inhibition of locomotion determines exploratory cell migration

PubMed Central

Lin, Benjamin; Yin, Taofei; Wu, Yi I.; Inoue, Takanari; Levchenko, Andre

2015-01-01

Directed cell migration in native environments is influenced by multiple migratory cues. These cues may include simultaneously occurring attractive soluble growth factor gradients and repulsive effects arising from cell-cell contact, termed contact inhibition of locomotion (CIL). How single cells reconcile potentially conflicting cues remains poorly understood. Here we show that a dynamic crosstalk between epidermal growth factor (EGF) mediated chemotaxis and CIL guide metastatic breast cancer cell motility, whereby cells become progressively insensitive to CIL in a chemotactic input-dependent manner. This balance is determined via integration of protrusion-enhancing signaling from EGF gradients and protrusion-suppressing signaling induced by CIL, mediated in part through EphB. Our results further suggest that EphB and EGF signaling inputs control protrusion formation by converging onto regulation of phosphatidylinositol 3-kinase (PI3K). We propose that this intricate interplay may enhance the spread of loose cell ensembles in pathophysiological conditions such as cancer, and possibly other physiological settings. PMID:25851023

Mechanism of Sleep Disturbance in Children with Atopic Dermatitis and the Role of the Circadian Rhythm and Melatonin

PubMed Central

Chang, Yung-Sen; Chiang, Bor-Luen

2016-01-01

Sleep disturbance is common in children with atopic dermatitis (AD). It is a major factor leading to impaired quality of life in these patients and could have negative effects on neurocognitive function and behavior. However, the pathophysiology of sleep disturbance in children with AD is poorly understood, and there is no consensus on how to manage sleep problems in these patients. Pruritus and scratching could lead to sleep disruption but is unlikely the sole etiology. The circadian rhythm of cytokines, the immune system, and skin physiology such as transcutaneous water loss and skin blood flow might also play a role. Recent studies have suggested that melatonin could also be involved due to its multiple effects on sleep, immunomodulation, and anti-oxidant ability. Environmental factors should also be considered. In this review, we summarize the current understanding of the pathophysiology of sleep disturbance in children with AD, and discuss possible therapeutic implications. PMID:27043528

Role of motor unit structure in defining function

NASA Technical Reports Server (NTRS)

Monti, R. J.; Roy, R. R.; Edgerton, V. R.

2001-01-01

Motor units, defined as a motoneuron and all of its associated muscle fibers, are the basic functional units of skeletal muscle. Their activity represents the final output of the central nervous system, and their role in motor control has been widely studied. However, there has been relatively little work focused on the mechanical significance of recruiting variable numbers of motor units during different motor tasks. This review focuses on factors ranging from molecular to macroanatomical components that influence the mechanical output of a motor unit in the context of the whole muscle. These factors range from the mechanical properties of different muscle fiber types to the unique morphology of the muscle fibers constituting a motor unit of a given type and to the arrangement of those motor unit fibers in three dimensions within the muscle. We suggest that as a result of the integration of multiple levels of structural and physiological levels of organization, unique mechanical properties of motor units are likely to emerge. Copyright 2001 John Wiley & Sons, Inc.

Mortality indicators and risk factors for intra-abdominal hypertension in severe acute pancreatitis.

PubMed

Zhao, J G; Liao, Q; Zhao, Y P; Hu, Y

2014-01-01

This study assessed the risk factors associated with mortality and the development of intra-abdominal hypertension (IAH) in patients with severe acute pancreatitis (SAP). To identify significant risk factors, we assessed the following variables in 102 patients with SAP: age, gender, etiology, serum amylase level, white blood cell (WBC) count, serum calcium level, Acute Physiology and Chronic Health Evaluation II (APACHE-II) score, computed tomography severity index (CTSI) score, pancreatic necrosis, surgical interventions, and multiple organ dysfunction syndrome (MODS). Statistically significant differences were identified using the Student t test and the χ (2) test. Independent risk factors for survival were analyzed by Cox proportional hazards regression. The following variables were significantly related to both mortality and IAH: WBC count, serum calcium level, serum amylase level, APACHE-II score, CTSI score, pancreatic necrosis, pancreatic necrosis >50%, and MODS. However, it was found that surgical intervention had no significant association with mortality. MODS and pancreatic necrosis >50% were found to be independent risk factors for survival in patients with SAP. Mortality and IAH from SAP were significantly related to WBC count, serum calcium level, serum amylase level, APACHE-II score, CTSI score, pancreatic necrosis, and MODS. However, Surgical intervention did not result in higher mortality. Moreover, MODS and pancreatic necrosis >50% predicted a worse prognosis in SAP patients.

tRNA and Its Activation Targets as Biomarkers and Regulators of Breast Cancer

DTIC Science & Technology

2013-09-01

linked tRNA misregulation to cancer. We have previously reported that tRNA levels are significantly elevated in breast cancer and multiple myeloma ...significantly elevated in breast cancer and multiple myeloma cells. To further investigate the cellular and physiological effects of tRNA overexpression, we...tRNA levels are elevated in breast cancer and multiple myeloma cell lines (Pavon-Eternod et al. 2009; Zhou et al. 2009). Though abnormal RNA polymerase

Guiding Principles for a Pediatric Neurology ICU (neuroPICU) Bedside Multimodal Monitor

PubMed Central

Eldar, Yonina C.; Gopher, Daniel; Gottlieb, Amihai; Lammfromm, Rotem; Mangat, Halinder S; Peleg, Nimrod; Pon, Steven; Rozenberg, Igal; Schiff, Nicholas D; Stark, David E; Yan, Peter; Pratt, Hillel; Kosofsky, Barry E

2016-01-01

Summary Background Physicians caring for children with serious acute neurologic disease must process overwhelming amounts of physiological and medical information. Strategies to optimize real time display of this information are understudied. Objectives Our goal was to engage clinical and engineering experts to develop guiding principles for creating a pediatric neurology intensive care unit (neuroPICU) monitor that integrates and displays data from multiple sources in an intuitive and informative manner. Methods To accomplish this goal, an international group of physicians and engineers communicated regularly for one year. We integrated findings from clinical observations, interviews, a survey, signal processing, and visualization exercises to develop a concept for a neuroPICU display. Results Key conclusions from our efforts include: (1) A neuroPICU display should support (a) rapid review of retrospective time series (i.e. cardiac, pulmonary, and neurologic physiology data), (b) rapidly modifiable formats for viewing that data according to the specialty of the reviewer, and (c) communication of the degree of risk of clinical decline. (2) Specialized visualizations of physiologic parameters can highlight abnormalities in multivariable temporal data. Examples include 3-D stacked spider plots and color coded time series plots. (3) Visual summaries of EEG with spectral tools (i.e. hemispheric asymmetry and median power) can highlight seizures via patient-specific “fingerprints.” (4) Intuitive displays should emphasize subsets of physiology and processed EEG data to provide a rapid gestalt of the current status and medical stability of a patient. Conclusions A well-designed neuroPICU display must present multiple datasets in dynamic, flexible, and informative views to accommodate clinicians from multiple disciplines in a variety of clinical scenarios. PMID:27437048

Guiding Principles for a Pediatric Neurology ICU (neuroPICU) Bedside Multimodal Monitor: Findings from an International Working Group.

PubMed

Grinspan, Zachary M; Eldar, Yonina C; Gopher, Daniel; Gottlieb, Amihai; Lammfromm, Rotem; Mangat, Halinder S; Peleg, Nimrod; Pon, Steven; Rozenberg, Igal; Schiff, Nicholas D; Stark, David E; Yan, Peter; Pratt, Hillel; Kosofsky, Barry E

2016-01-01

Physicians caring for children with serious acute neurologic disease must process overwhelming amounts of physiological and medical information. Strategies to optimize real time display of this information are understudied. Our goal was to engage clinical and engineering experts to develop guiding principles for creating a pediatric neurology intensive care unit (neuroPICU) monitor that integrates and displays data from multiple sources in an intuitive and informative manner. To accomplish this goal, an international group of physicians and engineers communicated regularly for one year. We integrated findings from clinical observations, interviews, a survey, signal processing, and visualization exercises to develop a concept for a neuroPICU display. Key conclusions from our efforts include: (1) A neuroPICU display should support (a) rapid review of retrospective time series (i.e. cardiac, pulmonary, and neurologic physiology data), (b) rapidly modifiable formats for viewing that data according to the specialty of the reviewer, and (c) communication of the degree of risk of clinical decline. (2) Specialized visualizations of physiologic parameters can highlight abnormalities in multivariable temporal data. Examples include 3-D stacked spider plots and color coded time series plots. (3) Visual summaries of EEG with spectral tools (i.e. hemispheric asymmetry and median power) can highlight seizures via patient-specific "fingerprints." (4) Intuitive displays should emphasize subsets of physiology and processed EEG data to provide a rapid gestalt of the current status and medical stability of a patient. A well-designed neuroPICU display must present multiple datasets in dynamic, flexible, and informative views to accommodate clinicians from multiple disciplines in a variety of clinical scenarios.

Cell–cell signaling drives the evolution of complex traits: introduction—lung evo-devo

PubMed Central

Torday, John S.; Rehan, V. K.

2009-01-01

Physiology integrates biology with the environment through cell–cell interactions at multiple levels. The evolution of the respiratory system has been “deconvoluted” (Torday and Rehan in Am J Respir Cell Mol Biol 31:8–12, 2004) through Gene Regulatory Networks (GRNs) applied to cell–cell communication for all aspects of lung biology development, homeostasis, regeneration, and aging. Using this approach, we have predicted the phenotypic consequences of failed signaling for lung development, homeostasis, and regeneration based on evolutionary principles. This cell–cell communication model predicts other aspects of vertebrate physiology as adaptational responses. For example, the oxygen-induced differentiation of alveolar myocytes into alveolar adipocytes was critical for the evolution of the lung in land dwelling animals adapting to fluctuating Phanarezoic oxygen levels over the past 500 million years. Adipocytes prevent lung injury due to oxygen radicals and facilitate the rise of endothermy. In addition, they produce the class I cytokine leptin, which augments pulmonary surfactant activity and alveolar surface area, increasing selection pressure for both respiratory oxygenation and metabolic demand initially constrained by high-systemic vascular pressure, but subsequently compensated by the evolution of the adrenomedullary beta-adrenergic receptor mechanism. Conserted positive selection for the lung and adrenals created further selection pressure for the heart, which becomes progressively more complex phylogenetically in tandem with the lung. Developmentally, increasing heart complexity and size impinges precociously on the gut mesoderm to induce the liver. That evolutionary-developmental interaction is significant because the liver provides regulated sources of glucose and glycogen to the evolving physiologic system, which is necessary for the evolution of the neocortex. Evolution of neocortical control furthers integration of physiologic systems. Such an evolutionary vertical integration of cell-to-tissue-to-organ-to-physiology of intrinsic cell–cell signaling and extrinsic factors is the reverse of the “top-down” conventional way in which physiologic systems are usually regarded. This novel mechanistic approach, incorporating a “middle-out” cell–cell signaling component, will lead to a readily available algorithm for integrating genes and phenotypes. This symposium surveyed the phylogenetic origins of such vertically integrated mechanisms for the evolution of cell–cell communication as the basis for complex physiologic traits, from sponges to man. PMID:20607136

Contributing Factors to Student Success in Anatomy and Physiology: Lower outside Workload and Better Preparation

ERIC Educational Resources Information Center

Harris, David E.; Hannum, Lynn; Gupta, Sat

2004-01-01

A study of students of a traditional two-semester Anatomy and Physiology class was made to determine factors that contributed to success in the coursework. The test established a co-relation between the amount of study in mathematics and science done previously in school and final grades in the subject.

Effects of High Dissolved Inorganic and Organic Carbon Availability on the Physiology of the Hard Coral Acropora millepora from the Great Barrier Reef

PubMed Central

Meyer, Friedrich W.; Vogel, Nikolas; Diele, Karen; Kunzmann, Andreas; Uthicke, Sven; Wild, Christian

2016-01-01

Coral reefs are facing major global and local threats due to climate change-induced increases in dissolved inorganic carbon (DIC) and because of land-derived increases in organic and inorganic nutrients. Recent research revealed that high availability of labile dissolved organic carbon (DOC) negatively affects scleractinian corals. Studies on the interplay of these factors, however, are lacking, but urgently needed to understand coral reef functioning under present and near future conditions. This experimental study investigated the individual and combined effects of ambient and high DIC (pCO2 403 μatm/ pHTotal 8.2 and 996 μatm/pHTotal 7.8) and DOC (added as Glucose 0 and 294 μmol L-1, background DOC concentration of 83 μmol L-1) availability on the physiology (net and gross photosynthesis, respiration, dark and light calcification, and growth) of the scleractinian coral Acropora millepora (Ehrenberg, 1834) from the Great Barrier Reef over a 16 day interval. High DIC availability did not affect photosynthesis, respiration and light calcification, but significantly reduced dark calcification and growth by 50 and 23%, respectively. High DOC availability reduced net and gross photosynthesis by 51% and 39%, respectively, but did not affect respiration. DOC addition did not influence calcification, but significantly increased growth by 42%. Combination of high DIC and high DOC availability did not affect photosynthesis, light calcification, respiration or growth, but significantly decreased dark calcification when compared to both controls and DIC treatments. On the ecosystem level, high DIC concentrations may lead to reduced accretion and growth of reefs dominated by Acropora that under elevated DOC concentrations will likely exhibit reduced primary production rates, ultimately leading to loss of hard substrate and reef erosion. It is therefore important to consider the potential impacts of elevated DOC and DIC simultaneously to assess real world scenarios, as multiple rather than single factors influence key physiological processes in coral reefs. PMID:26959499

Effects of High Dissolved Inorganic and Organic Carbon Availability on the Physiology of the Hard Coral Acropora millepora from the Great Barrier Reef.

PubMed

Meyer, Friedrich W; Vogel, Nikolas; Diele, Karen; Kunzmann, Andreas; Uthicke, Sven; Wild, Christian

2016-01-01

Coral reefs are facing major global and local threats due to climate change-induced increases in dissolved inorganic carbon (DIC) and because of land-derived increases in organic and inorganic nutrients. Recent research revealed that high availability of labile dissolved organic carbon (DOC) negatively affects scleractinian corals. Studies on the interplay of these factors, however, are lacking, but urgently needed to understand coral reef functioning under present and near future conditions. This experimental study investigated the individual and combined effects of ambient and high DIC (pCO2 403 μatm/ pHTotal 8.2 and 996 μatm/pHTotal 7.8) and DOC (added as Glucose 0 and 294 μmol L-1, background DOC concentration of 83 μmol L-1) availability on the physiology (net and gross photosynthesis, respiration, dark and light calcification, and growth) of the scleractinian coral Acropora millepora (Ehrenberg, 1834) from the Great Barrier Reef over a 16 day interval. High DIC availability did not affect photosynthesis, respiration and light calcification, but significantly reduced dark calcification and growth by 50 and 23%, respectively. High DOC availability reduced net and gross photosynthesis by 51% and 39%, respectively, but did not affect respiration. DOC addition did not influence calcification, but significantly increased growth by 42%. Combination of high DIC and high DOC availability did not affect photosynthesis, light calcification, respiration or growth, but significantly decreased dark calcification when compared to both controls and DIC treatments. On the ecosystem level, high DIC concentrations may lead to reduced accretion and growth of reefs dominated by Acropora that under elevated DOC concentrations will likely exhibit reduced primary production rates, ultimately leading to loss of hard substrate and reef erosion. It is therefore important to consider the potential impacts of elevated DOC and DIC simultaneously to assess real world scenarios, as multiple rather than single factors influence key physiological processes in coral reefs.

Large Impact of Low Concentration Oxidized LDL on Angiogenic Potential of Human Endothelial Cells: A Microarray Study

PubMed Central

Khaidakov, Magomed; Mitra, Sona; Wang, Xianwei; Ding, Zufeng; Bora, Nalini; Lyzogubov, Valery; Romeo, Francesco; Schichman, Steven A.; Mehta, Jawahar L.

2012-01-01

Oxidized LDL (ox-LDL) is a key factor in atherogenesis. It is taken up by endothelial cells primarily by ox-LDL receptor-1 (LOX-1). To elucidate transcriptional responses, we performed microarray analysis on human coronary artery endothelial cells (HCAECs) exposed to small physiologic concentration of ox-LDL- 5 µg/ml for 2 and 12 hours. At 12 hours, cultures treated with ox-LDL exhibited broad shifts in transcriptional activity involving almost 1500 genes (>1.5 fold difference, p<0.05). Resulting transcriptome was enriched for genes associated with cell adhesion (p<0.002), angiogenesis (p<0.0002) and migration (p<0.006). Quantitative PCR analysis revealed that LOX-1 expression in HCAECs is at least an order of magnitude greater than the expression of other major ox-LDL specific receptors CD36 and MSR1. In keeping with the data on LOX-1 expression, pre-treatment of HCAECs with LOX-1 neutralizing antibody resulted in across-the-board inhibition of cellular response to ox-LDL. Ox-LDL upregulated a number of pro-angiogenic genes including multiple receptors, ligands and transcription factors and altered the expression of a number of genes implicated in both stimulation and inhibition of apoptosis. From a functional standpoint, physiologic concentrations of ox-LDL stimulated tube formation and inhibited susceptibility to apoptosis in HCAECs. In addition, ox-LDL exposure resulted in upregulation of miR-1974, miR-1978 and miR-21 accompanied with significant over-presentation of their target genes in the downregulated portion of ox-LDL transcriptome. Our observations indicate that ox-LDL at physiologic concentrations induces broad transcriptional responses which are mediated by LOX-1, and are, in part, shaped by ox-LDL-dependent miRNAs. We also suggest that angiogenic effects of ox-LDL are partially based on upregulation of several receptors that render cells hypersensitive to angiogenic stimuli. PMID:23115646

The physiological basis for spacecraft environmental limits

NASA Technical Reports Server (NTRS)

Waligora, J. M. (Compiler)

1979-01-01

Limits for operational environments are discussed in terms of acceptable physiological changes. The environmental factors considered are pressure, contaminants, temperature, acceleration, noise, rf radiation, and weightlessness.

Noninvasive optical monitoring multiple physiological parameters response to cytokine storm

NASA Astrophysics Data System (ADS)

Li, Zebin; Li, Ting

2018-02-01

Cancer and other disease originated by immune or genetic problems have become a main cause of death. Gene/cell therapy is a highlighted potential method for the treatment of these diseases. However, during the treatment, it always causes cytokine storm, which probably trigger acute respiratory distress syndrome and multiple organ failure. Here we developed a point-of-care device for noninvasive monitoring cytokine storm induced multiple physiological parameters simultaneously. Oxy-hemoglobin, deoxy-hemoglobin, water concentration and deep-tissue/tumor temperature variations were simultaneously measured by extended near infrared spectroscopy. Detection algorithms of symptoms such as shock, edema, deep-tissue fever and tissue fibrosis were developed and included. Based on these measurements, modeling of patient tolerance and cytokine storm intensity were carried out. This custom device was tested on patients experiencing cytokine storm in intensive care unit. The preliminary data indicated the potential of our device in popular and milestone gene/cell therapy, especially, chimeric antigen receptor T-cell immunotherapy (CAR-T).

Amyloid-β Homeostasis Bridges Inflammation, Synaptic Plasticity Deficits and Cognitive Dysfunction in Multiple Sclerosis

PubMed Central

Stampanoni Bassi, Mario; Garofalo, Sara; Marfia, Girolama A.; Gilio, Luana; Simonelli, Ilaria; Finardi, Annamaria; Furlan, Roberto; Sancesario, Giulia M.; Di Giandomenico, Jonny; Storto, Marianna; Mori, Francesco; Centonze, Diego; Iezzi, Ennio

2017-01-01

Cognitive deficits are frequently observed in multiple sclerosis (MS), mainly involving processing speed and episodic memory. Both demyelination and gray matter atrophy can contribute to cognitive deficits in MS. In recent years, neuroinflammation is emerging as a new factor influencing clinical course in MS. Inflammatory cytokines induce synaptic dysfunction in MS. Synaptic plasticity occurring within hippocampal structures is considered as one of the basic physiological mechanisms of learning and memory. In experimental models of MS, hippocampal plasticity is profoundly altered by proinflammatory cytokines. Although mechanisms of inflammation-induced hippocampal pathology in MS are not completely understood, alteration of Amyloid-β (Aβ) metabolism is emerging as a key factor linking together inflammation, synaptic plasticity and neurodegeneration in different neurological diseases. We explored the correlation between concentrations of Aβ1–42 and the levels of some proinflammatory and anti-inflammatory cytokines (interleukin-1β (IL-1β), IL1-ra, IL-8, IL-10, IL-12, tumor necrosis factor α (TNFα), interferon γ (IFNγ)) in the cerebrospinal fluid (CSF) of 103 remitting MS patients. CSF levels of Aβ1–42 were negatively correlated with the proinflammatory cytokine IL-8 and positively correlated with the anti-inflammatory molecules IL-10 and interleukin-1 receptor antagonist (IL-1ra). Other correlations, although noticeable, were either borderline or not significant. Our data show that an imbalance between proinflammatory and anti-inflammatory cytokines may lead to altered Aβ homeostasis, representing a key factor linking together inflammation, synaptic plasticity and cognitive dysfunction in MS. This could be relevant to identify novel therapeutic approaches to hinder the progression of cognitive dysfunction in MS. PMID:29209169

Exploring metabolic dysfunction in chronic kidney disease

PubMed Central

2012-01-01

Impaired kidney function and chronic kidney disease (CKD) leading to kidney failure and end-stage renal disease (ESRD) is a serious medical condition associated with increased morbidity, mortality, and in particular cardiovascular disease (CVD) risk. CKD is associated with multiple physiological and metabolic disturbances, including hypertension, dyslipidemia and the anorexia-cachexia syndrome which are linked to poor outcomes. Specific hormonal, inflammatory, and nutritional-metabolic factors may play key roles in CKD development and pathogenesis. These include raised proinflammatory cytokines, such as interleukin-1 and −6, tumor necrosis factor, altered hepatic acute phase proteins, including reduced albumin, increased C-reactive protein, and perturbations in normal anabolic hormone responses with reduced growth hormone-insulin-like growth factor-1 axis activity. Others include hyperactivation of the renin-angiotensin aldosterone system (RAAS), with angiotensin II and aldosterone implicated in hypertension and the promotion of insulin resistance, and subsequent pharmacological blockade shown to improve blood pressure, metabolic control and offer reno-protective effects. Abnormal adipocytokine levels including leptin and adiponectin may further promote the insulin resistant, and proinflammatory state in CKD. Ghrelin may be also implicated and controversial studies suggest activities may be reduced in human CKD, and may provide a rationale for administration of acyl-ghrelin. Poor vitamin D status has also been associated with patient outcome and CVD risk and may indicate a role for supplementation. Glucocorticoid activities traditionally known for their involvement in the pathogenesis of a number of disease states are increased and may be implicated in CKD-associated hypertension, insulin resistance, diabetes risk and cachexia, both directly and indirectly through effects on other systems including activation of the mineralcorticoid receptor. Insight into the multiple factors altered in CKD may provide useful information on disease pathogenesis, clinical assessment and treatment rationale such as potential pharmacological, nutritional and exercise therapies. PMID:22537670

Examination of Psychosocial and Physiological Risk for Bulimic Symptoms in Youth With Type 1 Diabetes Transitioning to an Insulin Pump: A Pilot Study.

PubMed

Peterson, Claire M; Young-Hyman, Deborah; Fischer, Sarah; Markowitz, Jessica T; Muir, Andrew B; Laffel, Lori M

2018-01-01

This study tested hypotheses drawn from a risk model positing that psychosocial risk plus disease-related and treatment factors contribute to bulimic symptoms in youth with type 1 diabetes (T1D) transitioning to an insulin pump. The goal of this study was to examine whether disease-related factors, particularly disease- and treatment-based disruption in hunger and satiety, contribute to report of bulimic symptoms in youth with T1D after accounting for psychosocial risk factors. 43 youth (ages 10-17, 54% female) with established T1D were recruited before transition from multiple daily injections to insulin-pump therapy from three tertiary pediatric diabetes centers. Participants completed measures of bulimic symptoms, depressive symptoms dietary restraint, and the Diabetes Treatment and Satiety Scale, a diabetes-specific questionnaire assessing hunger and satiety cues and eating behavior in response to blood glucose levels and treatment. Hierarchical multiple regression was used to assess contributions of psychosocial and disease-based risk to report of bulimic symptoms. After assessing the contributions of body mass index, body image dissatisfaction, and dietary restraint, a significant 2-way interaction emerged between depression and diabetes-related uncontrollable hunger related to bulimic symptoms (β = 1.82, p < .01). In addition to psychosocial risk, disease- and treatment-based hunger and satiety dysregulation appear to be important factors contributing to report of bulimic symptoms in youth with T1D. These preliminary findings have significant treatment implications for bulimic symptoms in youth with T1D. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Exposure Factors Handbook Chapter 19

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 4

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 6

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 2

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 9

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 11

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 14

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 1

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 15

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 12

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 18

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 16

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 7

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 5

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 3

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 8

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 10

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 13

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Exposure Factors Handbook Chapter 17

EPA Pesticide Factsheets

Exposure Factors Handbook: 2011 Edition. The Exposure Factors Handbook provides information on various physiological and behavioral factors commonly used in assessing exposure to environmental chemicals.

Cellular Decision Making by Non-Integrative Processing of TLR Inputs.

PubMed

Kellogg, Ryan A; Tian, Chengzhe; Etzrodt, Martin; Tay, Savaş

2017-04-04

Cells receive a multitude of signals from the environment, but how they process simultaneous signaling inputs is not well understood. Response to infection, for example, involves parallel activation of multiple Toll-like receptors (TLRs) that converge on the nuclear factor κB (NF-κB) pathway. Although we increasingly understand inflammatory responses for isolated signals, it is not clear how cells process multiple signals that co-occur in physiological settings. We therefore examined a bacterial infection scenario involving co-stimulation of TLR4 and TLR2. Independent stimulation of these receptors induced distinct NF-κB dynamic profiles, although surprisingly, under co-stimulation, single cells continued to show ligand-specific dynamic responses characteristic of TLR2 or TLR4 signaling rather than a mixed response, comprising a cellular decision that we term "non-integrative" processing. Iterating modeling and microfluidic experiments revealed that non-integrative processing occurred through interaction of switch-like NF-κB activation, receptor-specific processing timescales, cell-to-cell variability, and TLR cross-tolerance mediated by multilayer negative feedback. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Life under Multiple Extreme Conditions: Diversity and Physiology of the Halophilic Alkalithermophiles

PubMed Central

Wiegel, Juergen

2012-01-01

Around the world, there are numerous alkaline, hypersaline environments that are heated either geothermally or through intense solar radiation. It was once thought that such harsh environments were inhospitable and incapable of supporting a variety of life. However, numerous culture-dependent and -independent studies revealed the presence of an extensive diversity of aerobic and anaerobic bacteria and archaea that survive and grow under these multiple harsh conditions. This diversity includes the halophilic alkalithermophiles, a novel group of polyextremophiles that require for growth and proliferation the multiple extremes of high salinity, alkaline pH, and elevated temperature. Life under these conditions undoubtedly involves the development of unique physiological characteristics, phenotypic properties, and adaptive mechanisms that enable control of membrane permeability, control of intracellular osmotic balance, and stability of the cell wall, intracellular proteins, and other cellular constituents. This minireview highlights the ecology and growth characteristics of the extremely halophilic alkalithermophiles that have been isolated thus far. Biochemical, metabolic, and physiological properties of the extremely halophilic alkalithermophiles are described, and their roles in resistance to the combined stressors of high salinity, alkaline pH, and high temperature are discussed. The isolation of halophilic alkalithermophiles broadens the physicochemical boundaries for life and extends the boundaries for the combinations of the maximum salinity, pH, and temperature that can support microbial growth. PMID:22492435

Shared control of gene expression in bacteria by transcription factors and global physiology of the cell

PubMed Central

Berthoumieux, Sara; de Jong, Hidde; Baptist, Guillaume; Pinel, Corinne; Ranquet, Caroline; Ropers, Delphine; Geiselmann, Johannes

2013-01-01

Gene expression is controlled by the joint effect of (i) the global physiological state of the cell, in particular the activity of the gene expression machinery, and (ii) DNA-binding transcription factors and other specific regulators. We present a model-based approach to distinguish between these two effects using time-resolved measurements of promoter activities. We demonstrate the strength of the approach by analyzing a circuit involved in the regulation of carbon metabolism in E. coli. Our results show that the transcriptional response of the network is controlled by the physiological state of the cell and the signaling metabolite cyclic AMP (cAMP). The absence of a strong regulatory effect of transcription factors suggests that they are not the main coordinators of gene expression changes during growth transitions, but rather that they complement the effect of global physiological control mechanisms. This change of perspective has important consequences for the interpretation of transcriptome data and the design of biological networks in biotechnology and synthetic biology. PMID:23340840

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.

Bioactive factors in milk across lactation: maternal effects and influence on infant growth in rhesus macaques (Macaca mulatta)

PubMed Central

Bernstein, Robin; Hinde, Katie

2017-01-01

Among mammals, numerous bioactive factors in milk vary across mothers and influence offspring outcomes. This emerging area of research has primarily investigated such dynamics within rodent biomedical models, domesticated dairy breeds, and among humans in clinical contexts. Less understood are signaling factors in the milk of non-human primates. Here, we report on multiple bioactive components in rhesus macaque (Macaca mulatta) milk and their associations with maternal and infant characteristics. Milk samples were collected from 59 macaques at multiple time points across lactation in conjunction with maternal and infant morphometrics and life-history animal records. Milk was assayed for adiponectin (APN), epidermal growth factor (EGF) and its receptor (EGF-R), and transforming growth factor beta 2 (TGF-β2). Regression models were constructed to assess the contributions of maternal factors on variation in milk bioactives, and on the relationship of this variation to infant body mass and growth. Maternal body mass, parity, social rank and infant sex were all predictive of concentrations of milk bioactives. Primiparous mothers produced milk with higher adiponectin, but lower EGF, than multiparous mothers. Heavier mothers produced milk with lower EGF and EGF-R, but higher TGF-β2. Mothers of daughters produced milk with higher TGF-β2. Mid-ranking mothers produced milk with higher mean EGF and adiponectin concentrations than low-ranking mothers. Milk EGF and EGF-R were positively associated with infant body mass and growth rate. Importantly, these signaling bioactives (APN, EGF, EGF-R, TGF-β2) were significantly correlated with nutritional values of milk. The effects of milk signals remained after controlling for the available energy in milk revealing the added physiological role of non-nutritive milk bioactives in the developing infant. Integrating analyses of energetic and other bioactive components of milk yields an important perspective for interpreting the magnitude, sources, and consequences of inter-individual variation in milk synthesis. PMID:27029025

A general multiple-compartment model for the transport of trace elements through animals

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

Assimakopoulos, P.A.; Ioannides, K.G.; Pakou, A.A.

1991-08-01

Multiple-compartment models employed in the analysis of trace element transport in animals are often based on linear differential equations which relate the rate of change of contaminant (or contaminant concentration) in each compartment to the amount of contaminant (or contaminant concentration) in every other compartment in the system. This has the serious disadvantage of mixing intrinsic physiological properties with the geometry of the animal. The basic equations on which the model presented here is developed are derived from the actual physical process under way and are capable of separating intrinsic physiological properties from geometry. It is thus expected that ratemore » coefficients determined through this model will be applicable to a wider category of physiologically similar animals. A specific application of the model for the study of contamination of sheep--or indeed for any ruminant--is presented, and the temporal evolution of contaminant concentration in the various compartments of the animal is calculated. The application of this model to a system of compartments with changing geometry is also presented.« less

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

Intrinsic optical signal imaging of glucose-stimulated physiological responses in the insulin secreting INS-1 β-cell line

NASA Astrophysics Data System (ADS)

Li, Yi-Chao; Cui, Wan-Xing; Wang, Xu-Jing; Amthor, Franklin; Yao, Xin-Cheng

2011-03-01

Intrinsic optical signal (IOS) imaging has been established for noninvasive monitoring of stimulus-evoked physiological responses in the retina and other neural tissues. Recently, we extended the IOS imaging technology for functional evaluation of insulin secreting INS-1 cells. INS-1 cells provide a popular model for investigating β-cell dysfunction and diabetes. Our experiments indicate that IOS imaging allows simultaneous monitoring of glucose-stimulated physiological responses in multiple cells with high spatial (sub-cellular) and temporal (sub-second) resolution. Rapid image sequences reveal transient optical responses that have time courses comparable to glucose-evoked β-cell electrical activities.

The centrifuge facility - A life sciences research laboratory for Space Station Freedom

NASA Technical Reports Server (NTRS)

Fuller, Charles A.; Johnson, Catherine C.; Hargens, Alan R.

1991-01-01

The paper describes the centrifugal facility that is presently being developed by NASA for studies aboard the Space Station Freedom on the role of gravity, or its absence, at varying intensities for varying periods of time and with multiple model systems. Special attention is given to the design of the centrifuge system, the habitats designed to hold plants and animals, the glovebox system designed for experimental manipulations of the specimens, and the service unit. Studies planned for the facility will include experiments in the following disciplines: cell and developmental biology, plant biology, regulatory physiology, musculoskeletal physiology, behavior and performance, neurosciences, cardiopulmonary physiology, and environmental health and radiation.

Changing physiological status predicts severe injury and need for specialized trauma center resources.

PubMed

Talbert, Steven

2009-01-01

This study evaluated the association between changing physiological status (delta data) with severe injury (SI) or need for trauma center resources (TCR). Prehospital and emergency department arrival weighted RTS (RTSw) were computed for patients with complete records entered into the registry from 2002 to 2004 (n = 23,753). Physiological change was classified as unchanged, deteriorated, or improved (PreRTSw vs EDRTSw). Performance of delta data was evaluated using standard epidemiological approaches and multiple logistic regression. Deterioration status predicted SI (operating room [OR] = 1.38) and TCR (OR = 2.09). Improved status predicted TCR (OR = 1.27). Delta data independently predicted both SI and TCR.

Exploring student preferences with a Q-sort: the development of an individualized renal physiology curriculum

PubMed Central

Roberts, John K.; Hargett, Charles W.; Nagler, Alisa; Jakoi, Emma

2015-01-01

Medical education reform is underway, but the optimal course for change has yet to be seen. While planning for the redesign of a renal physiology course at the Duke School of Medicine, the authors used a Q-sort survey to assess students' attitudes and learning preferences to inform curricular change. The authors invited first-year medical students at the Duke School of Medicine to take a Q-sort survey on the first day of renal physiology. Students prioritized statements related to their understanding of renal physiology, learning preferences, preferred course characteristics, perceived clinical relevance of renal physiology, and interest in nephrology as a career. By-person factor analysis was performed using the centroid method. Three dominant factors were strongly defined by learning preferences: “readers” prefer using notes, a textbook, and avoid lectures; “social-auditory learners” prefer attending lectures, interactivity, and working with peers; and “visual learners” prefer studying images, diagrams, and viewing materials online. A smaller, fourth factor represented a small group of students with a strong predisposition against renal physiology and nephrology. In conclusion, the Q-sort survey identified and then described in detail the dominant viewpoints of our students. Learning style preferences better classified first-year students rather than any of the other domains. A more individualized curriculum would simultaneously cater to the different types of learners in the classroom. PMID:26330030

Factors Affecting the Length of Stay in the Intensive Care Unit: Our Clinical Experience

PubMed Central

Sengul Samanci, Nilay; Akkoc, İbrahim; Yucetas, Esma; Cebeci, Egemen; Ozturk, Savas

2018-01-01

Background and Aim Long hospital days in intensive care unit (ICU) due to life-threatening diseases are increasing in the world. The primary goal in ICU is to decrease length of stay in order to improve the quality of medical care and reduce cost. The aim of our study is to identify and categorize the factors associated with prolonged stays in ICU. Materials and Method We retrospectively analyzed 3925 patients. We obtained the patients' demographic, clinical, diagnostic, and physiologic variables; mortality; lengths of stay by examining the intensive care unit database records. Results The mean age of the study was 61.6 ± 18.9 years. The average length of stay in intensive care unit was 10.2 ± 25.2 days. The most common cause of hospitalization was because of multiple diseases (19.5%). The length of stay was positively correlated with urea, creatinine, and sodium. It was negatively correlated with uric acid and hematocrit levels. Length of stay was significantly higher in patients not operated on than in patients operated on (p < 0.001). Conclusion Our study showed a significantly increased length of stay in patients with cardiovascular system diseases, multiple diseases, nervous system diseases, and cerebrovascular diseases. Moreover we showed that when urea, creatinine, and sodium values increase, in parallel the length of stay increases. PMID:29750174

Non-lethal control of the cariogenic potential of an agent-based model for dental plaque.

PubMed

Head, David A; Marsh, Phil D; Devine, Deirdre A

2014-01-01

Dental caries or tooth decay is a prevalent global disease whose causative agent is the oral biofilm known as plaque. According to the ecological plaque hypothesis, this biofilm becomes pathogenic when external challenges drive it towards a state with a high proportion of acid-producing bacteria. Determining which factors control biofilm composition is therefore desirable when developing novel clinical treatments to combat caries, but is also challenging due to the system complexity and the existence of multiple bacterial species performing similar functions. Here we employ agent-based mathematical modelling to simulate a biofilm consisting of two competing, distinct types of bacterial populations, each parameterised by their nutrient uptake and aciduricity, periodically subjected to an acid challenge resulting from the metabolism of dietary carbohydrates. It was found that one population was progressively eliminated from the system to give either a benign or a pathogenic biofilm, with a tipping point between these two fates depending on a multiplicity of factors relating to microbial physiology and biofilm geometry. Parameter sensitivity was quantified by individually varying the model parameters against putative experimental measures, suggesting non-lethal interventions that can favourably modulate biofilm composition. We discuss how the same parameter sensitivity data can be used to guide the design of validation experiments, and argue for the benefits of in silico modelling in providing an additional predictive capability upstream from in vitro experiments.

A New Mechanism for the Regulation of Stomatal Aperture Size in Intact Leaves (Accumulation of Mesophyll-Derived Sucrose in the Guard-Cell Wall of Vicia faba).

PubMed Central

Lu, P.; Outlaw Jr, W. H.; Smith, B. G.; Freed, G. A.

1997-01-01

At various times after pulse-labeling broad bean (Vicia faba L.) leaflets with 14CO2, whole-leaf pieces and rinsed epidermal peels were harvested and subsequently processed for histochemical analysis. Cells dissected from whole leaf retained apoplastic contents, whereas those from rinsed peels contained only symplastic contents. Sucrose (Suc)-specific radioactivity peaked (111 GBq mol-1) in palisade cells at 20 min. In contrast, the 14C content and Sucspecific radioactivity were very low in guard cells for 20 min, implying little CO2 incorporation; both then peaked at 40 min. The guard-cell apoplast had a high maximum Suc-specific radioactivity (204 GBq mol-1) and a high Suc influx rate (0.05 pmol stoma-1 min-1). These and other comparisons implied the presence of (a) multiple Suc pools in mesophyll cells, (b) a localized mesophyll-apoplast region that exchanges with phloem and stomata, and (c) mesophyll-derived Suc in guard-cell walls sufficient to diminish stomatal opening by approximately 3 [mu]m. Factors expected to enhance Suc accumulation in guard-cell walls are (a) high transpiration rate, which closes stomata, and (b) high apoplastic Suc concentration, which is elevated when mesophyll Suc efflux exceeds translocation. Therefore, multiple physiological factors are integrated in the attenuation of stomatal aperture size by this previously unrecognized mechanism. PMID:12223693

Disruptions in Energy Balance: Does Nature overcome Nurture?

PubMed Central

Fernández, José R.; Casazza, Krista; Divers, Jasmin; López-Alarcón, Mardya

2008-01-01

Fat accumulation, in general, is the result of a breakdown in the homeostatic regulation of energy balance. Although, the specific factors influencing the disruption of energy balance and why these factors affect individuals differently are not completely understood, numerous studies have identified multiple contributors. Environmental components influence food acquisition, eating, and lifestyle habits. However, the variability in obesity-related outcomes observed among individuals placed in similar controlled environments support the notion that genetic components also wield some control. Multiple genetic regions have been associated with measures related to energy balance; however, the replication of these genetic contributors to energy intake and energy expenditure in humans is relatively small perhaps because of the heterogeneity of human populations. Genetic tools such as genetic admixture account for individual’s genetic background in gene association studies, reducing the confounding effect of population stratification, and promise to be a relevant tool on the identification of genetic contributions to energy balance, particularly among individuals of diverse racial/ethnic backgrounds. Although it has been recognized that genes are expressed according to environmental influences, the search toward the understanding of nature and nurture in obesity will require the detailed study of the effect of genes under diverse physiologic and behavioral environments. It is evident that more research is needed to elucidate the methodological and statistical issues that underlie the interactions between genes and environments in obesity and its related comorbidities. PMID:18096193

Cellular IRES-mediated translation: the war of ITAFs in pathophysiological states.

PubMed

Komar, Anton A; Hatzoglou, Maria

2011-01-15

Translation of cellular mRNAs via initiation at Internal Ribosome Entry Sites (IRESs) has received increased attention during recent years due to its emerging significance for many physiological and pathological stress conditions in eukaryotic cells. Expression of genes bearing IRES elements in their mRNAs is controlled by multiple molecular mechanisms, with IRES-mediated translation favored under conditions when cap-dependent translation is compromised. In this review, we discuss recent advances in the field and future directions that may bring us closer to understanding the complex mechanisms that guide cellular IRES-mediated expression. We present examples in which the competitive action of IRES-transacting factors (ITAFs) plays a pivotal role in IRES-mediated translation and thereby controls cell-fate decisions leading to either pro-survival stress adaptation or cell death.

The teratogenic risk.

PubMed

Tuchmann-Duplessis, H

1983-01-01

Reproduction can be impaired in animals and man by drugs and various environmental agents. Depending on the time of exposure--from fertilization through the fetal period and eventually during lactation--the consequences can range from embryotoxicity, gross malformations and a large variety of more subtle morphological, biochemical, and functional abnormalities. The high susceptibility of the embryo to exogenous agents is due to cellular multiplication and differentiation and to the lack of development of the enzyme systems necessary for the detoxification of chemicals. At present, developmental impairments represent the main cause of perinatal mortality and postnatal morbidity. After a review of prenatal physiology and teratogenic principles, the action of selected drugs and environmental agents is analyzed. The potential danger of environmental factors during intrauterine development is of particular concern because of its irreversible nature.

Neuronal modulation of D. melanogaster sexual behaviour.

PubMed

Ellendersen, Bárður Eyjólfsson; von Philipsborn, Anne C

2017-12-01

Drosophila melanogaster sexual behaviour relies on well-studied genetically determined neuronal circuits. At the same time, it can be flexible and is modulated by multiple external and internal factors. This review focuses on how physiological state, behavioural context and social experience impact sexual circuits in the two sexes. We discuss how females tune receptivity and other behaviours depending on mating status and how males adjust courtship intensity based on sexual satiety, age and the conflicting drive for aggression. Neuronal mechanisms for behavioural modulation include changes in sensory and central processing. Activity of modulatory neurons can enhance, suppress or reverse the behavioural response to sensory cues. In summary, fly sexual behaviour is an excellent model to study mechanisms of neuromodulation of complex innate behaviour on the circuit level. Copyright © 2017 Elsevier Inc. All rights reserved.

Adverse effects of anticancer agents that target the VEGF pathway.

PubMed

Chen, Helen X; Cleck, Jessica N

2009-08-01

Antiangiogenesis agents that target the VEGF/VEGF receptor pathway have become an important part of standard therapy in multiple cancer indications. With expanded clinical experience with this class of agents has come the increasing recognition of the diverse adverse effects related to disturbance of VEGF-dependent physiological functions and homeostasis in the cardiovascular and renal systems, as well as wound healing and tissue repair. Although most adverse effects of VEGF inhibitors are modest and manageable, some are associated with serious and life-threatening consequences, particularly in high-risk patients and in certain clinical settings. This Review examines the toxicity profiles of anti-VEGF antibodies and small-molecule inhibitors. The potential mechanisms of the adverse effects, risk factors, and the implications for selection of patients and management are discussed.

Intersection of Stress, Social Disadvantage, and Life Course Processes: Reframing Trauma and Mental Health.

PubMed

Nurius, Paula S; Uehara, Edwina; Zatzick, Douglas F

2013-04-01

This paper describes the intersection of converging lines of research on the social structural, psychosocial, and physiological factors involved in the production of stress and implications for the field of mental health. Of particular interest are the stress sensitization consequences stemming from exposure to adversity over the life course. Contemporary stress sensitization theory provides important clinical utility in articulating mechanisms through which these multiple levels exert influence on mental health. Stress sensitization models (a) extend understanding of neurobiological and functional contexts within which extreme stressors operate and (b) make clear how these can influence psychologically traumatic outcomes. The value of interventions that are sensitive to current contexts as well as life course profiles of cumulative stress are illustrated through recent treatment innovations.

Light Signaling in Bud Outgrowth and Branching in Plants

PubMed Central

Leduc, Nathalie; Roman, Hanaé; Barbier, François; Péron, Thomas; Huché-Thélier, Lydie; Lothier, Jérémy; Demotes-Mainard, Sabine; Sakr, Soulaiman

2014-01-01

Branching determines the final shape of plants, which influences adaptation, survival and the visual quality of many species. It is an intricate process that includes bud outgrowth and shoot extension, and these in turn respond to environmental cues and light conditions. Light is a powerful environmental factor that impacts multiple processes throughout plant life. The molecular basis of the perception and transduction of the light signal within buds is poorly understood and undoubtedly requires to be further unravelled. This review is based on current knowledge on bud outgrowth-related mechanisms and light-mediated regulation of many physiological processes. It provides an extensive, though not exhaustive, overview of the findings related to this field. In parallel, it points to issues to be addressed in the near future. PMID:27135502

Cellular mechanisms of estradiol-mediated sexual differentiation of the brain.

PubMed

Wright, Christopher L; Schwarz, Jaclyn S; Dean, Shannon L; McCarthy, Margaret M

2010-09-01

Gonadal steroids organize the developing brain during a perinatal sensitive period and have enduring consequences for adult behavior. In male rodents testicular androgens are aromatized in neurons to estrogens and initiate multiple distinct cellular processes that ultimately determine the masculine phenotype. Within specific brain regions, overall cell number and dendritic morphology are the principal targets for hormonal organization. Recent advances have been made in elucidating the cellular mechanisms by which the neurological underpinnings of sexually dimorphic physiology and behavior are determined. These include estradiol-mediated prostaglandin synthesis, presynaptic release of glutamate, postsynaptic changes in glutamate receptors and changes in cell adhesion molecules. Sex differences in cell death are mediated by hormonal modulation of survival and death factors such as TNFalpha and Bcl-2/BAX. Copyright 2010 Elsevier Ltd. All rights reserved.

Endoplasmic Reticulum-Plasma Membrane Contact Sites.

PubMed

Saheki, Yasunori; De Camilli, Pietro

2017-06-20

The endoplasmic reticulum (ER) has a broad localization throughout the cell and forms direct physical contacts with all other classes of membranous organelles, including the plasma membrane (PM). A number of protein tethers that mediate these contacts have been identified, and study of these protein tethers has revealed a multiplicity of roles in cell physiology, including regulation of intracellular Ca 2+ dynamics and signaling as well as control of lipid traffic and homeostasis. In this review, we discuss the cross talk between the ER and the PM mediated by direct contacts. We review factors that tether the two membranes, their properties, and their dynamics in response to the functional state of the cell. We focus in particular on the role of ER-PM contacts in nonvesicular lipid transport between the two bilayers mediated by lipid transfer proteins.

Intersection of Stress, Social Disadvantage, and Life Course Processes: Reframing Trauma and Mental Health

PubMed Central

Nurius, Paula S.; Uehara, Edwina; Zatzick, Douglas F.

2015-01-01

This paper describes the intersection of converging lines of research on the social structural, psychosocial, and physiological factors involved in the production of stress and implications for the field of mental health. Of particular interest are the stress sensitization consequences stemming from exposure to adversity over the life course. Contemporary stress sensitization theory provides important clinical utility in articulating mechanisms through which these multiple levels exert influence on mental health. Stress sensitization models (a) extend understanding of neurobiological and functional contexts within which extreme stressors operate and (b) make clear how these can influence psychologically traumatic outcomes. The value of interventions that are sensitive to current contexts as well as life course profiles of cumulative stress are illustrated through recent treatment innovations. PMID:25729337

Platelet-derived growth factor inhibits platelet activation in heparinized whole blood.

PubMed

Selheim, F; Holmsen, H; Vassbotn, F S

1999-08-15

We previously have demonstrated that human platelets have functionally active platelet-derived growth factor alpha-receptors. Studies with gel-filtered platelets showed that an autocrine inhibition pathway is transduced through this tyrosine kinase receptor during platelet activation. The physiological significance of this inhibitory effect of platelet-derived growth factor on gel-filtered platelets activation is, however, not known. In the present study, we investigated whether platelet-derived growth factor inhibits platelet activation under more physiological conditions in heparinized whole blood, which represents a more physiological condition than gel-filtered platelets. Using flow cytometric assays, we demonstrate here that platelet-derived growth factor inhibits thrombin-, thrombin receptor agonist peptide SFLLRN-, and collagen-induced platelet aggregation and shedding of platelet-derived microparticles from the platelet plasma membrane during platelet aggregation in stirred heparinized whole blood. The inhibitory effect of platelet-derived growth factor was dose dependent. However, under nonaggregating conditions (no stirring), we could not demonstrate any significant effect of platelet-derived growth factor on thrombin- and thrombin receptor agonist peptide-induced platelet surface expression of P-selectin. Our results demonstrate that platelet-derived growth factor appears to be a true antithrombotic agent only under aggregating conditions in heparinized whole blood.

Earpiece with sensors to measure/monitor multiple physiological variables

NASA Technical Reports Server (NTRS)

Cooper, Tommy G. (Inventor); Schulze, Arthur E. (Inventor)

2003-01-01

An apparatus and method for positioning sensors relative to one another and anatomic features in a non-invasive device for measuring and monitoring multiple physiological variables from a single site uses an earpiece incorporating a shielded pulse oximetry sensor (POS) having a miniaturized set of LEDs and photosensors configured for pulse oximetry measurements in the reflectance mode and located in the earpiece so as to position the POS against a rear wall of an ear canal. The earpiece also includes a thermopile of no larger than 7 mm. in diameter located on the earpiece to so as to position the thermopile past a second turn of an external auditory meatus so as to view the tympanic membrane. The thermopile includes a reference temperature sensor attached to its base for ambient temperature compensation.

Physiologic monitoring. A guide to networking your monitoring systems.

PubMed

2011-10-01

There are many factors to consider when choosing a physiologic monitoring system. not only should these systems perform well clinically, but they should also be able to exchange data with other information systems. We discuss some of the ins and outs of physiologic monitoring system networking and highlight eight product lines from seven suppliers.

Drug Sensitivity in Older Adults: The Role of Physiologic and Pharmacokinetic Factors.

ERIC Educational Resources Information Center

Cherry, Katie E.; Morton, Mark R.

1989-01-01

Notes that age-related changes in physiology and pharmacokinetics (how drugs are used in the body) lead to increased drug sensitivity and potentially harmful drug effects. Addresses heightened sensitivity to drug effects seen in older adults. Presents three examples of physiologic decline and discusses some broad considerations for geriatric…

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

ERIC Educational Resources Information Center

Torbert, James Brison

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

Student Perceptions and Learning Outcomes of Blended Learning in a Massive First-Year Core Physiology for Allied Health Subjects

ERIC Educational Resources Information Center

Page, Janelle; Meehan-Andrews, Terri; Weerakkody, Nivan; Hughes, Diane L.; Rathner, Joseph A.

2017-01-01

Evidence shows that factors contributing to success in physiology education for allied health students at universities include not only their high school achievement and background but also factors such as confidence with their teachers and quality of their learning experience, justifying intensive and continued survey of students' perceptions of…

Effects of an Employee Wellness Program on Physiological Risk Factors, Job Satisfaction, and Monetary Savings in a South Texas University

ERIC Educational Resources Information Center

Hamilton, Jacqueline

2009-01-01

An experimental study was conducted to investigate the effects of an Employee Wellness Program on physiological risk factors, job satisfaction, and monetary savings in a South Texas University. The non-probability sample consisted of 31 employees from lower income level positions. The employees were randomly assigned to the treatment group which…

Endogenous Pyrogen Physiology.

ERIC Educational Resources Information Center

Beisel, William R.

1980-01-01

Discusses the physiology of endogenous pyrogen (EP), the fever-producing factor of cellular origin. Included are: its hormone-like role, its molecular nature, bioassay procedures, cellular production and mechanisms of EP action. (SA)

The physiology and biomechanics of competitive swimming.

PubMed

Troup, J P

1999-04-01

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

Predictors of iron levels in 14,737 Danish blood donors: results from the Danish Blood Donor Study.

PubMed

Rigas, Andreas Stribolt; Sørensen, Cecilie Juul; Pedersen, Ole Birger; Petersen, Mikkel Steen; Thørner, Lise Wegner; Kotzé, Sebastian; Sørensen, Erik; Magnussen, Karin; Rostgaard, Klaus; Erikstrup, Christian; Ullum, Henrik

2014-03-01

Dietary studies show a relationship between the intake of iron enhancers and inhibitors and iron stores in the general population. However, the impact of dietary factors on the iron stores of blood donors, whose iron status is affected by blood donations, is incompletely understood. In the Danish Blood Donor Study, we assessed the effect of blood donation frequency, physiologic factors, lifestyle and supplemental factors, and dietary factors on ferritin levels. We used multiple linear and logistic regression analyses stratified by sex and menopausal status. Among high-frequency donors (more than nine donations in the past 3 years), we found iron deficiency (ferritin below 15 ng/mL) in 9, 39, and 22% of men, premenopausal women, and postmenopausal women, respectively. The strongest predictors of iron deficiency were sex, menopausal status, the number of blood donations in a 3-year period, and the time since last donation. Other significant factors included weight, age, intensity of menstruation, iron tablets, vitamin pills, and consumption of meat and wine. The study confirms iron deficiency as an important problem, especially among menstruating women donating frequently. The risk of iron depletion was largely explained by sex, menopausal status, and donation frequency. Other factors, including dietary and supplemental iron intake, had a much weaker effect on the risk of iron depletion. © 2013 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

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 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

Can multi-generational exposure to ocean warming and acidification lead to the adaptation of life history and physiology in a marine metazoan?

PubMed

Gibbin, Emma M; Chakravarti, Leela J; Jarrold, Michael D; Christen, Felix; Turpin, Vincent; Massamba N'Siala, Gloria; Blier, Pierre U; Calosi, Piero

2017-02-15

Ocean warming and acidification are concomitant global drivers that are currently threatening the survival of marine organisms. How species will respond to these changes depends on their capacity for plastic and adaptive responses. Little is known about the mechanisms that govern plasticity and adaptability or how global changes will influence these relationships across multiple generations. Here, we exposed the emerging model marine polychaete Ophryotrocha labronica to conditions simulating ocean warming and acidification, in isolation and in combination over five generations to identify: (i) how multiple versus single global change drivers alter both juvenile and adult life-history traits; (ii) the mechanistic link between adult physiological and fitness-related life-history traits; and (iii) whether the phenotypic changes observed over multiple generations are of plastic and/or adaptive origin. Two juvenile (developmental rate; survival to sexual maturity) and two adult (average reproductive body size; fecundity) life-history traits were measured in each generation, in addition to three physiological (cellular reactive oxygen species content, mitochondrial density, mitochondrial capacity) traits. We found that multi-generational exposure to warming alone caused an increase in juvenile developmental rate, reactive oxygen species production and mitochondrial density, decreases in average reproductive body size and fecundity, and fluctuations in mitochondrial capacity, relative to control conditions. Exposure to ocean acidification alone had only minor effects on juvenile developmental rate. Remarkably, when both drivers of global change were present, only mitochondrial capacity was significantly affected, suggesting that ocean warming and acidification act as opposing vectors of stress across multiple generations. © 2017. Published by The Company of Biologists Ltd.

Transcription elongation. Heterogeneous tracking of RNA polymerase and its biological implications.

PubMed

Imashimizu, Masahiko; Shimamoto, Nobuo; Oshima, Taku; Kashlev, Mikhail

2014-01-01

Regulation of transcription elongation via pausing of RNA polymerase has multiple physiological roles. The pausing mechanism depends on the sequence heterogeneity of the DNA being transcribed, as well as on certain interactions of polymerase with specific DNA sequences. In order to describe the mechanism of regulation, we introduce the concept of heterogeneity into the previously proposed alternative models of elongation, power stroke and Brownian ratchet. We also discuss molecular origins and physiological significances of the heterogeneity.

Assessment of anorexia nervosa in children and adolescents.

PubMed

Weaver, Laurel; Liebman, Ronald

2011-04-01

Anorexia nervosa is a debilitating illness that affects mostly females and their families. Multiple physiologic disturbances are present and can be life-threatening. Nutritional rehabilitation is the foremost initial treatment goal. Assessment skills include understanding the physiologic, developmental, and psychiatric status of the individual as well as engagement of the family system. A comprehensive assessment that stimulates patient and family to successfully engage in treatment is the cornerstone of good clinical care for this highly disabling disorder.

Effects of Yoga on Physiological Indices, Anxiety and Social Functioning in Multiple Sclerosis Patients: A Randomized Trial

PubMed Central

Hasanpour-Dehkordi, Ali; Solati, Kamal

2016-01-01

Introduction Multiple sclerosis (MS) as a chronic disease could affect patients’ various domains of life. Aim This study was conducted to study the effect of yoga on the physiological indices, anxiety and social functioning of patients with MS in southwest, Iran. Materials and Methods In this clinical trial study, 60 MS patients were enrolled according to inclusion criteria and randomly assigned to two groups of 30 each. Prior to and after intervention, the patients’ vital signs were measured. For case group yoga exercises were performed three sessions a week for 12 weeks while control group performed no exercise. The data were gathered by questionnaire and analysed by descriptive and analytical statistics in SPSS. Results Prior to intervention, there was no significant difference in fatigue severity and pain between the two groups but the mean fatigue severity and pain in case group decreased compared to the control group after the intervention. Prior to intervention, there was no significant difference in mean physiological indices between the two groups but the mean physiological indices in case group decreased significantly after the intervention (p<0.05). Conclusion Yoga is likely to increase self-efficacy of MS patients through enhancing physical activity, increasing the strength of lower limbs and balance, and decreasing fatigue and pain, and finally to promote social functioning and to relieve stress and anxiety in these patients. PMID:27504387

Evaluating learning among undergraduate medical students in schools with traditional and problem-based curricula.

PubMed

Meo, Sultan Ayoub

2013-09-01

This study aimed to assess knowledge and skills in a respiratory physiology course in traditional versus problem-based learning (PBL) groups in two different medical schools. Two different undergraduate medical schools were selected for this study. The first medical school followed the traditional [lecture-based learning (LBL)] curriculum, and the second medical school followed the PBL curriculum. Sixty first-year male medical students (30 students from each medical school) volunteered; they were apparently healthy and of the same age, sex, nationality, and regional and cultural background. Students were taught respiratory physiology according to their curriculum for a period of 2 wk. At the completion of the study period, knowledge was measured based on a single best multiple-choice question examination, and skill was measured based on the objective structured practical examination in the lung function laboratory (respiratory physiology). A Student's t-test was applied for the analysis of the data, and the level of significance was set at P < 0.05. Students belonging to the PBL curriculum obtained a higher score in the multiple-choice question examination (P = 0.001) and objective structured practical examination (P = 0.0001) compared with traditional (LBL) students. Students in the PBL group obtained significantly higher knowledge and skill scores in the respiratory physiology course compared with students in the traditional (LBL) style of medical schools.

[Preliminary study on evaluation system of mental workers strain based on primary and middle school teachers].

PubMed

Lian, Yulong; Liu, Jiwen; Zhang, Chen; Yuan, Fang

2010-09-01

To use primary and middle schools teacher as samples to preliminarily build the mental work stress effect evaluation system, providing the methological platform for the research on the stress effect mechanism and mental workers interference measures. 851 teachers in primary and middle schools were selected with randomly stratified cluster methods. Use ISTA 6.0 and Life Events Evaluation Table to measure the stress factors, and use Work Tension Reaction Questionnaire, Symptom Self-Evaluation Table Questionnaire, and General Happiness Sensing Table to measure psychological stress reaction, blood sugar and blood fat, blood cortical, ACTH, nerve behavior function, for measuring physiological stress reaction. The Comprehensive Working Ability Index Table to measure working ability. And then use the mathematical model to build the mental workers stress effect evaluation system. And apply the simple random sampling method to select 400 environmental protection workers to perform cross effect validation. The model fits relatively well (RMSEA = 0.100, GFI = 0.93, NNFI = 1.00, CFI = 1.00) and conforms with the theory, reflecting the loads of the indice, such as, working stress reaction, psychological stress reaction, physiological stress reaction and working ability, are relatively high. At the same time, the stress reaction of those 4 dimensions can fit the 2-grade factor (stress effect) very well. The physiological stress reaction is negatively correlated (P < 0.05) with the working stress reaction, psychological stress reaction, working ability decrease, while is positively correlated (P < 0.05) with the working stress, psychological stress reaction, physiological stress reaction and working ability decrease. The social support is the protection factor for working stress, psychological stress reaction, physiological stress reaction and working ability decrease (gamma(s) are -0.55, -0.77, 0.73, -0.79, respectively, P < 0.05). While working stress factors, social life stress factors and dangerous individual characters are the risk factors (P < 0.05) for working stress, psychological stress reaction, physiological stress reaction increase and the working ability decrease. The utilization of the environment protection workers further validates this model. It conforms with the theory to evaluate the mental workers stress effects from the 4 dimensions, working stress, psychological stress reaction, physiological stress reaction, and working ability. And these 4 dimensions influence each other, and also are mutually different. The working and social life stress factors influence the stress effects with certain degrees. This evaluation model can tentatively be the methodological basis for the mental workers occupational stress evaluation.

Effects of work-related sleep restriction on acute physiological and psychological stress responses and their interactions: A review among emergency service personnel.

PubMed

Wolkow, Alexander; Ferguson, Sally; Aisbett, Brad; Main, Luana

2015-01-01

Emergency work can expose personnel to sleep restriction. Inadequate amounts of sleep can negatively affect physiological and psychological stress responses. This review critiqued the emergency service literature (e.g., firefighting, police/law enforcement, defense forces, ambulance/paramedic personnel) that has investigated the effect of sleep restriction on hormonal, inflammatory and psychological responses. Furthermore, it investigated if a psycho-physiological approach can help contextualize the significance of such responses to assist emergency service agencies monitor the health of their personnel. The available literature suggests that sleep restriction across multiple work days can disrupt cytokine and cortisol levels, deteriorate mood and elicit simultaneous physiological and psychological responses. However, research concerning the interaction between such responses is limited and inconclusive. Therefore, it is unknown if a psycho-physiological relationship exists and as a result, it is currently not feasible for agencies to monitor sleep restriction related stress based on psycho- physiological interactions. Sleep restriction does however, appear to be a major stressor contributing to physiological and psychological responses and thus, warrants further investigation. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Early-Life Effects on Adult Physical Activity: Concepts, Relevance, and Experimental Approaches.

PubMed

Garland, Theodore; Cadney, Marcell D; Waterland, Robert A

Locomotion is a defining characteristic of animal life and plays a crucial role in most behaviors. Locomotion involves physical activity, which can have far-reaching effects on physiology and neurobiology, both acutely and chronically. In human populations and in laboratory rodents, higher levels of physical activity are generally associated with positive health outcomes, although excessive exercise can have adverse consequences. Whether and how such relationships occur in wild animals is unknown. Behavioral variation among individuals arises from genetic and environmental factors and their interactions as well as from developmental programming (persistent effects of early-life environment). Although tremendous progress has been made in identifying genetic and environmental influences on individual differences in behavior, early-life effects are not well understood. Early-life effects can in some cases persist across multiple generations following a single exposure and, in principle, may constrain or facilitate the rate of evolution at multiple levels of biological organization. Understanding the mechanisms of such transgenerational effects (e.g., exposure to stress hormones in utero, inherited epigenetic alterations) may prove crucial to explaining unexpected and/or sex-specific responses to selection as well as limits to adaptation. One area receiving increased attention is early-life effects on adult physical activity. Correlational data from epidemiological studies suggest that early-life nutritional stress can (adversely) affect adult human activity levels and associated physiological traits (e.g., body composition, metabolic health). The few existing studies of laboratory rodents demonstrate that both maternal and early-life exercise can affect adult levels of physical activity and related phenotypes. Going forward, rodents offer many opportunities for experimental studies of (multigenerational) early-life effects, including studies that use maternal exposures and cross-fostering designs.

Proteomic analysis of Bombyx mori molting fluid: Insights into the molting process.

PubMed

Liu, Hua-Wei; Wang, Luo-Ling; Tang, Xin; Dong, Zhao-Ming; Guo, Peng-Chao; Zhao, Dong-Chao; Xia, Qing-You; Zhao, Ping

2018-02-20

Molting is an essential biological process occurring multiple times throughout the life cycle of most Ecdysozoa. Molting fluids accumulate and function in the exuvial space during the molting process. In this study, we used liquid chromatography-tandem mass spectrometry to investigate the molting fluids to analyze the molecular mechanisms of molting in the silkworm, Bombyx mori. In total, 375 proteins were identified in molting fluids from the silkworm at 14-16h before pupation and eclosion, including 12 chitin metabolism-related enzymes, 35 serine proteases, 15 peptidases, and 38 protease inhibitors. Gene ontology analysis indicated that "catalytic" constitutes the most enriched function in the molting fluid. Gene expression patterns and bioinformatic analyses suggested that numerous enzymes are involved in the degradation of cuticle proteins and chitin. Protein-protein interaction network and activity analyses showed that protease inhibitors are involved in the regulation of multiple pathways in molting fluid. Additionally, many immune-related proteins may be involved in the immune defense during molting. These results provide a comprehensive proteomic insight into proteolytic enzymes and protease inhibitors in molting fluid, and will likely improve the current understanding of physiological processes in insect molting. Insect molting constitutes a dynamic physiological process. To better understand this process, we used LC-MS/MS to investigate the proteome of silkworm molting fluids and identified key proteins involved in silkworm molting. The biological processes of the old cuticle degradation pathway and immune defense response were analyzed in the proteome of silkworm molting fluid. We report that protease inhibitors serve as key factors in the regulation of the molting process. The proteomic results provide new insight into biological molting processes in insects. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Are Your Students Ready for Anatomy and Physiology? Developing Tools to Identify Students at Risk for Failure

ERIC Educational Resources Information Center

Gultice, Amy; Witham, Ann; Kallmeyer, Robert

2015-01-01

High failure rates in introductory college science courses, including anatomy and physiology, are common at institutions across the country, and determining the specific factors that contribute to this problem is challenging. To identify students at risk for failure in introductory physiology courses at our open-enrollment institution, an online…

Physiological Factors in Adult Learning and Instruction. Research to Practice Series.

ERIC Educational Resources Information Center

Verner, Coolie; Davison, Catherine V.

The physiological condition of the adult learner as related to his learning capability is discussed. The design of the instructional process, the selection of learning tasks, the rate at which instruction occurs, and the nature of the instructional setting may all be modified by the instructor to accomodate the variable physiological conditions of…

Soldier Performance as a Function of Stress and Load: A Review

DTIC Science & Technology

1990-01-01

1985) increasing load obstacle course decreased weight performance Ikai & Steinhaus shouting forearm flex strength increased (1961) gun shot increased...performance. Capacity represents relatively fil1 ed physiological limits of behavior, while performance is a function of psychological factors (Ikai & Steinhaus ...3), 513-524. Ikai, M., & Steinhaus , A. H. (1961). Some factors modifying the expression of human strength. Journal of ADnlied Physiology, 15, 157-163

Protein Turnover Measurements in Human Serum by Serial Immunoaffinity LC-MS/MS.

PubMed

Farrokhi, Vahid; Chen, Xiaoying; Neubert, Hendrik

2018-02-01

The half-life of target proteins is frequently an important parameter in mechanistic pharmacokinetic and pharmacodynamic (PK/PD) modeling of biotherapeutics. Clinical studies for accurate measurement of physiologically relevant protein turnover can reduce the uncertainty in PK/PD model-based predictions, for example, of the therapeutic dose and dosing regimen in first-in-human clinical trials. We used a targeted mass spectrometry work flow based on serial immunoaffinity enrichment ofmultiple human serum proteins from a [5,5,5- 2 H 3 ]-L-leucine tracer pulse-chase study in healthy volunteers. To confirm the reproducibility of turnover measurements from serial immunoaffinity enrichment, multiple aliquots from the same sample set were subjected to protein turnover analysis in varying order. Tracer incorporation was measured by multiple-reaction-monitoring mass spectrometry and target turnover was calculated using a four-compartment pharmacokinetic model. Five proteins of clinical or therapeutic relevance including soluble tumor necrosis factor receptor superfamily member 12A, tissue factor pathway inhibitor, soluble interleukin 1 receptor like 1, soluble mucosal addressin cell adhesion molecule 1, and muscle-specific creatine kinase were sequentially subjected to turnover analysis from the same human serum sample. Calculated half-lives ranged from 5-15 h; however, no tracer incorporation was observed for mucosal addressin cell adhesion molecule 1. The utility of clinical pulse-chase studies to investigate protein turnover can be extended by serial immunoaffinity enrichment of target proteins. Turnover analysis from serum and subsequently from remaining supernatants provided analytical sensitivity and reproducibility for multiple human target proteins in the same sample set, irrespective of the order of analysis. © 2017 American Association for Clinical Chemistry.

Predicting the oral pharmacokinetic profiles of multiple-unit (pellet) dosage forms using a modeling and simulation approach coupled with biorelevant dissolution testing: case example diclofenac sodium.

PubMed

Kambayashi, Atsushi; Blume, Henning; Dressman, Jennifer B

2014-07-01

The objective of this research was to characterize the dissolution profile of a poorly soluble drug, diclofenac, from a commercially available multiple-unit enteric coated dosage form, Diclo-Puren® capsules, and to develop a predictive model for its oral pharmacokinetic profile. The paddle method was used to obtain the dissolution profiles of this dosage form in biorelevant media, with the exposure to simulated gastric conditions being varied in order to simulate the gastric emptying behavior of pellets. A modified Noyes-Whitney theory was subsequently fitted to the dissolution data. A physiologically-based pharmacokinetic (PBPK) model for multiple-unit dosage forms was designed using STELLA® software and coupled with the biorelevant dissolution profiles in order to simulate the plasma concentration profiles of diclofenac from Diclo-Puren® capsule in both the fasted and fed state in humans. Gastric emptying kinetics relevant to multiple-units pellets were incorporated into the PBPK model by setting up a virtual patient population to account for physiological variations in emptying kinetics. Using in vitro biorelevant dissolution coupled with in silico PBPK modeling and simulation it was possible to predict the plasma profile of this multiple-unit formulation of diclofenac after oral administration in both the fasted and fed state. This approach might be useful to predict variability in the plasma profiles for other drugs housed in multiple-unit dosage forms. Copyright © 2014 Elsevier B.V. All rights reserved.

Deficiencies of Circulating Mucosal-associated Invariant T Cells and Natural Killer T Cells in Patients with Multiple Trauma.

PubMed

Jo, Young Goun; Choi, Hyun Jung; Kim, Jung Chul; Cho, Young Nan; Kang, Jeong Hwa; Jin, Hye Mi; Kee, Seung Jung; Park, Yong Wook

2017-05-01

Mucosal-associated invariant T (MAIT) cells and natural killer T (NKT) cells are known to play important roles in autoimmunity, infectious diseases and cancers. However, little is known about the roles of these invariant T cells in multiple trauma. The purposes of this study were to examine MAIT and NKT cell levels in patients with multiple trauma and to investigate potential relationships between these cell levels and clinical parameters. The study cohort was composed of 14 patients with multiple trauma and 22 non-injured healthy controls (HCs). Circulating MAIT and NKT cell levels in the peripheral blood were measured by flow cytometry. The severity of injury was categorised according to the scoring systems, such as Acute Physiology and Chronic Health Evaluation (APACHE) II score, Simplified Acute Physiology Score (SAPS) II, and Injury Severity Score (ISS). Circulating MAIT and NKT cell numbers were significantly lower in multiple trauma patients than in HCs. Linear regression analysis showed that circulating MAIT cell numbers were significantly correlated with age, APACHE II, SAPS II, ISS category, hemoglobin, and platelet count. NKT cell numbers in the peripheral blood were found to be significantly correlated with APACHE II, SAPS II, and ISS category. This study shows numerical deficiencies of circulating MAIT cells and NKT cells in multiple trauma. In addition, these invariant T cell deficiencies were found to be associated with disease severity. These findings provide important information for predicting the prognosis of multiple trauma. © 2017 The Korean Academy of Medical Sciences.

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.

Multiple-time scales analysis of physiological time series under neural control

NASA Technical Reports Server (NTRS)

Peng, C. K.; Hausdorff, J. M.; Havlin, S.; Mietus, J. E.; Stanley, H. E.; Goldberger, A. L.

1998-01-01

We discuss multiple-time scale properties of neurophysiological control mechanisms, using heart rate and gait regulation as model systems. We find that scaling exponents can be used as prognostic indicators. Furthermore, detection of more subtle degradation of scaling properties may provide a novel early warning system in subjects with a variety of pathologies including those at high risk of sudden death.