OBJECTIVE: Work stress contributes to risk of coronary heart disease and hypertension. This study tested the influence of job control on ambulatory blood pressure, and ratings of perceived stress and happiness in men and women systematically sampled by socio-economic status from the Whitehall II epidemiological cohort. PARTICIPANTS: A total of ...

Experiments have been undertaken exposing larval common shrimp (Crangon crangon) and lobster (Homarus gammarus) and adult copepods (Acartia tonsa) to the key stresses of entrainment within power-station cooling-water systems. The apparatus has enabled the testing of mechanical, thermal, chlorine and realistic pressure effects both alone and in combination, the range ...

Healthy physiological processes require the complex interaction of multiple control systems operating over multiple time scales. The output of these processes (for example, heart rate, blood pressure, hormonal rhythms, or postural sway) demonstrates complex variability that can be quantified using the concept of fractals, derived from the field of nonlinear ...

Borderline personality disorder (BPD) is a highly prevalent and disabling condition linked to early stressors including traumatic abuse and abandonment. While much work has addressed traumatic events in childhood, little is known about the biological sequelae of BPD including how this disorder may be differentiated from other stress-related disorders such ...

Recent studies call into question the necessity of hypertrophic growth of the heart as a "compensatory" response to hemodynamic stress. These findings, coupled with recent progress in dissecting the molecular bases of hypertrophy, raise the prospect of suppressing hypertrophy without provoking circulatory insufficiency. In this article, we focus on signaling ...

Lactate is formed and utilized continuously under fully aerobic conditions. Lactate is oxidized actively at all times, especially during exercise. Family of monocarboxylate transport proteins (MCTs) that are differentially expressed in cells and tissues accomplishes the facilitated transport of lactate across membranes. Previously we reported that there is MCT1 in ...

BACKGROUND: Iron overload has an increasing worldwide prevalence and is associated with significant cardiovascular morbidity and mortality. Elevated iron levels in the myocardium lead to impaired systolic and diastolic function and elevated oxidative stress. Taurine accounts for 25% to 50% of the amino acid pool in myocardium, possesses antioxidant properties, ...

Environmental factors in early life are clearly established risk factors for cardiovascular disease in later life. Most studies have focused on nutritional programming and analysed basal cardiovascular parameters rather than responses. In the present study we have investigated whether prenatal stress has long-term effects on cardiovascular responses in adult offspring. ...

BACKGROUND: Vascular Ehlers-Danlos syndrome (vEDS), also known as EDS type IV, an inherited disorder of connective tissue, results from mutations in the gene encoding type III procollagen (COL3A1). Affected patients are at risk for arterial dissection or rupture, the main cause of death. To understand the pathogenesis of the vascular ...

The reduction of tidal volume during mechanical ventilation has been shown to reduce mortality of patients with acute respiratory distress syndrome, but epithelial cell injury can still result from mechanical stresses imposed by the opening of occluded airways. To study these stresses, a fluid-filled parallel-plate flow chamber lined with epithelial ...

Biliary duct obstruction is an important clinical condition that stems from cholelithiasis, the neoplasm in the wall or, most commonly, gallbladder stones. The objective of this study is to understand the structural and mechanical remodeling of the common bile duct (CBD) postobstruction. Porcine CBD was ligated near the duodenum that ...

The aim was to evaluate the cardiovascular and subjective stress response to a combined physical and mental workload, and the effect of rest. Twelve females who had no prior experience of laboratory experiments participated in the study. Computer-work-related mental stressors were either added to or removed from a standardized computer ...

Experiments tested the effect of stress coupled with cholinesterase inhibition on blood pressure, heart rate, baroreflex index, and variability in time and frequency domain in conscious mice. The objective was to determine whether cholinergic systems interact with stress to alter cardiovascular responses. Male C57BL/6J mice with arterial catheters were exposed ...

In northern Italy in 1997, two earthquakes of magnitudes 5.7 and 6 (separated by nine hours) marked the beginning of a sequence that lasted more than 30 days, with thousands of aftershocks including four additional events with magnitudes between 5 and 6. This normal-faulting sequence is not well explained with ...

BACKGROUND: The downward movement of the aortic root during the cardiac cycle may be responsible for producing the circumferential tear observed in aortic dissections. METHODS AND RESULTS: Contrast injections were investigated in 40 cardiac patients, and a finite element model of the aortic root, arch, and branches of the arch ...

The objective of the present study was to gain insight into the effects of precision demands and mental pressure on the load of the upper extremity. Two computer mouse tasks were used: an aiming and a tracking task. Upper extremity loading was operationalized as the myo-electric activity of the wrist ...

This study was originally planned from September tenth through twelfth to assess concurrent use of three real-time data sources during a usual day. When the World Trade Center towers collapsed, the plan expanded to describe 24-hour blood pressure and heart rate, natural environment word use, television viewing/radio listening, and self-reported ...

I hypothesize that urbanization Murrells Inlet will affect the total number of elasmobranches present and the species diversity of elasmobranchs. I believe predation is the controlling factor for newborn sharks and young juveniles, and so I would expect to find those individuals in the areas least accessible to adult sharks. ...

We have designed a new type of aortic cannula for extracorporeal circulation which we hypothesize has superior haemodynamic characteristics compared with existing types. The aim of the study was to perform a quantitative evaluation of the haemodynamic performance of commercially available aortic cannulas against our new design. Six existing cannulas ...

The purpose of this research was to investigate whether patients experiencing nonspecific complaints of the forearm caused by sustained use of the personal computer exhibit deviant movement strategies as compared to healthy participants. Patients (N=10) and controls (N=24) performed a graphical aiming task combined with an auditory memory task. Force ...

Although enhanced cardiovascular reactivity is extensively discussed as a relevant negative factor in the alteration of vascular structure, only a few controlled studies have been published presenting approaches to alter reactivity. Therefore, we examined whether enhanced reactivity could be reduced by stress management training (SMT). To control for expectation effects, ...

Psychometric properties of a questionnaire measuring psychosocial work-related stress in terms of effort-reward imbalance and a short family stress scale were examined in a population sample of 421 working women from four work sites in Beijing, China. The internal consistency of the scales was satisfactory, and the theoretically postulated structure ...

Wall reinforcement in xylem conduits is thought to prevent wall implosion by negative pressures, but direct observations of xylem geometry during water stress are still largely lacking. In this study, we have analyzed the changes in xylem geometry during water stress in needles of four pine species (Pinus spp.). Dehydrated ...

Left ventricular hypertrophy has been shown to be an independent predictor of risk for cardiovascular morbidity and mortality. Behavioral scientists have focused on how hemodynamic factors influenced by psychosocial stress may be associated with left ventricular mass (LVM). We reviewed existing studies examining stress-related cardiovascular reactivity (CVR) and LVM, with ...

Conventional cardiovascular risk factors such as cholesterol and blood pressure do not account fully for variation in coronary heart disease suggesting the involvement of additional mechanisms. We have examined the effects of a chronic psychological stress protocol on the development of atherosclerosis in the apolipoprotein E knockout mouse. We observed ...

To identify unique cardiovascular responses to stressors in a population at genetic risk of hypertension, we studied haemodynamic responses in initial reactivity to, subsequent adaptation to, and final recovery from repeated active mental stress in young, normotensive individuals stratified by hypertension parental history (PH). Two groups (n=21/group) of normotensive white ...

OBJECTIVE: This epidemiological study examined whether the magnitude of blood pressure reactions to mental stress was associated with future blood pressure and whether the strength of association was affected by sex, age, and socioeconomic position. MATERIALS AND METHODS: Resting blood pressure was recorded at initial baseline and in response to ...

A conspicuous long-term consequence of hypertension is a thickening of the arterial wall, which many suggest returns the circumferential wall stress toward its normal value. This thickening results from an increase in smooth muscle and extracellular matrix, with the associated growth and remodeling processes depending on a host of regulatory ...

The purpose of this study was to determine if there are gender differences in stress-induced pressure natriuresis and to examine the effects of adiposity on these differences. The subjects were 151 boys and 141 girls 15 to 18 years of age who underwent a 5-hour stress protocol (2-hour prestress, 1-hour ...

This study sought to examine the psychophysiological correlates of forgiveness in response to interpersonal conflict. One hundred eight college students (44 males and 64 females) participated in two interviews about times of interpersonal betrayal, one about a parent and one about a friend/partner. Measures of forgiving personality and state forgiveness ...

Some asthma patients and physicians who treat asthma have reported that stress worsens their disease. It has also recently been shown that chronic stressful life events increase airway inflammation 6-24 h after inhalation of antigen in patients with allergic asthma. However, there is no data regarding the effect of an ...

We propose to initiate the automatic self-assessment of wear and tear as "stress and strain" by the time structures of blood pressure (BP) and heart rate (HR), in order to arrive eventually at an individualized timely and timed routine of life and to early preventive intervention as soon as needed. ...

Mitochondrial integrity is critical in the maintenance of bioenergetic homeostasis of the myocardium, with oxidative or metabolic challenge to mitochondria precipitating cell injury. In heart failure, where cardiac cells are exposed to elevated stress, mitochondrial vulnerability could contribute to the disease state. However, the mitochondrial response to stress is yet ...

BACKGROUND: The use of music as a method of relieving anxiety has been studied extensively by researchers from varying disciplines. The abundance of these reports focused on which genre of music best aided in the relief of stress. Little work has been performed in the area of auditory preference in ...

OBJECTIVE: The relationship between Type D personality (the joint tendency towards negative affectivity [NA] and social inhibition [SI]) and laboratory indices of cardiovascular health was examined. METHOD: 173 undergraduates (86 male) completed a stress protocol involving a mental arithmetic task with harassment. Blood pressure, heart rate (HR), and salivary cortisol ...

In this study, the relationship between repressive and defensive coping styles and somatovisceral responses as well as emotion self-reports were investigated in 2 situational contexts conceived to induce fear and anger. Anxiety (State-Trait Anxiety Inventory; L. Laux, P. Glanzmann, P. Schaffner, and C. D. Spielberger, 1981) x Defensiveness (Marlowe-Crowne Social ...

Epinephrine (E) and norepinephrine (NE) play a major role in regulating metabolism and cardiovascular physiology. Both are secreted in response to stress and their measurement in plasma allows the study of sympathoadrenal function. Several studies investigating sympathoadrenal physiology are conducted using mice. Review of the literature revealed that basal mouse ...

OBJECTIVE: This research examined hemodynamic processes in cardiovascular reactivity (CVR) as a function of task, ethnicity and trait hostility. METHOD: One hundred and fourteen male patrol officers from the Singapore Police Force participated in this experimental study. Trait hostility was measured using the interpersonal hostility assessment technique to derive a ...

Allostasis designates processes of bodily adaptation to stressful challenges, whereas allostatic load means the costs of wear and tear to the body as a consequence of inefficient allostasis. In distressed dementia caregivers, an acute procoagulant stress response might be one dynamic mediator of allostatic load relevant to cardiovascular endpoints. An ...

Stress of some kind is encountered everyday and release of stress hormones is essential for adaptation to change. Stress can be physical (pain, noise exposure, etc.), psychological (apprehension to impending events, acoustic conditioning, etc.) or due to homeostatic disturbance (hunger, blood pressure, inner ear pressure, etc.). Persistent elevated levels of ...

Spontaneous baroreflex control of pulse interval (PI) was assessed in healthy volunteers under thermoneutral and heat stress conditions. Subjects rested in the supine position with their lower legs in a water bath at 34 degrees C. Heat stress was imposed by increasing the bath temperature to 44 degrees C. Arterial ...

OBJECTIVE: The role of tonic sympathetic stimulation on the properties of large arteries is largely unknown. The purpose of this study was to determine the effect of mental stress on hemodynamics and arterial properties in mild hypertensives. METHOD: Twenty-three subjects with mild hypertension and 19 age-matched normotensives were compared to ...

The influence of hostility levels on verbal and nonverbal fluency, and the concurrent cerebral regulation of autonomic nervous system functioning was examined in 48 right-handed males, half classified as low-hostile, and half as high-hostile. Recent research has supported inhibitory roles for the anterior right cerebrum in sympathetic regulation, and the ...

The best method for processing allograft bone to prevent disease transmission without compromising its biomechanical function is not yet determined. We evaluated the biomechanical effects of processing bulk allograft bone segments with negative-pressure washing. Specimens were prepared from matched pairs of adult cadaveric femurs. The experimental femur underwent routine processing, ...

The pulsatile ac component (DeltaI) superimposed on the transmitted dc components (I: tissue plus blood) are obtained from a near-infrared finger photoplethysmogram using a wavelength of 810 nm. Only the dc component is given in an ischaemic circulatory state (I(t): tissue only). Based on Lambert-Beer's law, normalized pulse volume (NPV; ...

The epidermal growth factor (EGF) is a growth factor with effects on many cell types and tissue. Morphometric and passive biomechanical properties were studied in isolated segments of the esophagus in 22 EGF-treated rats and 12 control rats. The rats were divided into groups with EGF treatment for 2, 4, ...

Associations between natural killer (NK) cell, proinflammatory cytokine stress responsivity, and cardiac autonomic responses (indexed by heart rate and heart rate variability) were assessed in 211 middle-aged men and women. Blood was drawn at baseline, immediately following color-word interference and mirror tracing tasks for the assessment of NK cell numbers, ...

There is growing evidence that stress contributes to cardiovascular disease. Chronic stress contributes to the atherosclerotic process through increased allostatic load, which is mediated by the neuroendocrine and immune systems (sympathetic nervous system and hypothalamus-pituitary adrenal axis) and related chronic risk factors (insulin resistance syndrome, hypertension, diabetes, and hyperlipidemia). In ...

OBJECTIVE: This study evaluated the prospective relationship between cardiovascular reactivity to psychological stress and increases in resting blood pressure across a 3-year period among a multiethnic pediatric sample (N = 149). METHODS: Systolic and diastolic blood pressure; EKG heart rate, pre-ejection period, and mean successive difference of R to R ...

We report long-term temporal consistency of stress-related neuroendocrine and cardiovascular variables in mid-aged and older women who performed mental math and speech stress tasks two times approximately 1 year apart. Epinephrine, norepinephrine, ACTH, cortisol, cardiac preejection period (PEP), respiratory sinus arrhythmia, heart rate (HR), blood pressure, and respiration rate were ...