Introduction. Patients with essential hypertension react more strongly to mental stress than normotensives. This may be related to the type of stress coping or to increased reactivity associated with the disease. The aim of our study was to examine whether patients with essential or secondary hypertension differ in their reaction ...

This study examined the moderator effects of heart rate variability, a physiological marker of stress vulnerability, on the relationship between race-related stress and psychological distress in African Americans (N = 215). Participants were administered the Index of Race-Related Stress-Brief and the Brief Symptom Inventory-18. Resting heart rate was recorded using ...

OBJECTIVE: The aim of this study was to investigate whether systemic systolic hypertension (SHT) and diastolic hypertension (DHT) are associated with an exaggerated response of factor VII clotting activity (FVII:C), factor VIII clotting activity (FVIII:C), fibrinogen, and d-dimer to acute psychosocial stress. METHODS: We performed the 15-min Trier Social Stress ...

To test the hypothesis that cutaneous active vasodilation in heat stress is mediated by a redundant cholinergic cotransmitter system, we examined the effects of atropine on skin blood flow (SkBF) increases during heat stress in persons with (CF) and without cystic fibrosis (non-CF). Vasoactive intestinal peptide (VIP) has been implicated ...

BACKGROUND: A hypertensive response to exercise (HRE) is associated with false-positive stress echocardiograms and myocardial perfusion single photon emission computed tomography (myocardial perfusion imaging [MPI]) defects even in the absence of coronary artery disease (CAD). Transient ischemic dilation (TID) of the left ventricle on stress MPI is a marker of ...

Some pathological conditions may affect osmolarity, which can impact cell, tissue, and organ volume. The hypothesis of this study is that changes in osmolarity affect the zero-stress state and mechanical properties of the aorta. To test this hypothesis, a segment of mouse abdominal aorta was cannulated in vivo and mechanically ...

The present work describes that under increasing physical load the voice fundamental frequency (voice pitch) remains on a given level as long as the physical load is well tolerated by the subject, whereas heart rate and blood pressure continuously increase during increasing physical load. This voice pitch level was compared ...

The concentration of mechanical stress in soft tissue can cause or worsen pressure sores. We have previously reported the results of analysis of stress concentration in soft tissue using a finite element model. In the present study, we hypothesized that even if a cushion pad was thin, it would effectively ...

BACKGROUND: Oxidative stress plays an important role in the pathogenesis of atherosclerosis. Advanced oxidation protein products (AOPP) are markers of oxidative stress and mediators of inflammation. Increased arterial stiffness is associated with increased risk of cardiovascular mortality and morbidity. The aim of this study was to evaluate the relationship between ...

Posttraumatic stress disorder (PTSD) involves the onset of psychiatric symptoms after exposure to a traumatic event. PTSD has an estimated lifetime prevalence of 7.8% among adult Americans, and about 15.2% of the men and 8.5% of the women who served in Vietnam suffered from posttraumatic stress disorder (PTSD) > or ...

Vulnerable plaque morphology has been described by gross pathology and intravascular ultrasound, but morphological criteria cannot fully explain vulnerability, which involves four distinct factors: 1) inflammatory and biological processes; 2) geometry; 3) composition; and 4) hemodynamic stress. These last three aspects underlie the biomechanical study of vulnerable plaque. By virtue ...

Stress has been recognized as an important contributing factor to many forms of cardiovascular diseases. Its quantification has been sought for decades, but to no avail. We have developed a wholly noninvasive approach to quantitatively assess mental and physical stress effects on parameters that are associated with global cardiovascular function. ...

Because stress is a major factor in hypertension, research on parenting stressors and lifestyle behaviors of grandparents with hypertension is important. This study describes urban African Americans caring for grandchildren and examines effects of perceived parenting stress-ors on hypertension self-management. Hypertensive African American grandparents (N = 49) residing in a ...

http://deepblue.lib.umich.edu/bitstream/2027.42/51459/1/Jennings JR, Exaggerated Blood Pressure Responses During Mental Stress, 2004.pdf

BACKGROUND: A maximal negative stress echo identifies a low risk for subsequent hard events subset. However, the potentially prognostically relevant information on global contractile reserve on the left ventricle is missed by standard regional wall motion assessment, and can be obtained by end-systolic pressure-volume relationship (PVR) evaluation. AIM: To assess ...

Experimental mental stress by a computerized color word conflict test was developed. The effects of a single oral administration of two different β-blockers, carvedilol (a vasodilating β-/α_1-blocker, 20 mg) and metoprolol (a β_1-selective blocker, 20 mg), on a color word conflict test (mental stress)-induced increase in heart rate and systolic ...

Cardiovascular responses occur not only in the immediate presence of stressors, but also while later thinking about those experiences. Evidence suggests that these delayed responses, such as those produced by ruminating about prior angering experiences, may play an important role in the development of cardiovascular disease. We examine whether physiological ...

Functional dyspepsia (FD) is associated with impaired gastric accommodation and autonomic dysregulation. The aim of this study was to investigate the effects of autonomic manipulation on distension-induced gastric accommodation in subjects with and without FD, using a newly developed gastric barostat paradigm. Twelve healthy subjects (HS) and 18 subjects with ...

The mortality and neurological morbidity in heatstroke have been attributed to the host's inflammatory responses to heat stress, suggesting that anti-inflammatory therapy may improve outcome. We tested the hypothesis that a high dose of dexamethasone protects baboons against the lethal effects of heatstroke. Ten anesthetized baboons (Papio hamadryas) were assigned ...

PURPOSE: We previously reported marked elevation of glutamate, gamma-aminobutyric acid (GABA) and alanine in the vitreous after combined cataract surgery and vitrectomy for macular disorder. Photo-stimulation by the operating microscope and increased intraocular pressure (IOP) are possible causes of postoperative increases in amino acids. An animal model was used to ...

BACKGROUND: Dobutamine (Dob) stress myocardial perfusion scintigraphy (MPS) has been shown to have diagnostic and prognostic value. However, the protocol recommended for Dob-MPS is long and frequently associated with adverse effects. We sought to compare two stress protocols with Dob in patients undergoing MPS. METHODS AND RESULTS: 168 patients undergoing ...

The gravitational stress encountered by pilots of high-performance aircraft can cause dramatic shifts in blood volume and circulatory pressure, thus placing the cardiovascular system under significant stress, sometimes resulting in loss of consciousness due to cerebral under-perfusion. Since pilots experience both increased and decreased gravitational stress in high-risk environments, it ...

The purpose of the present investigation was to examine the association between cardiovascular reactivity to provocation and physically and relationally aggressive conduct. Blood pressure and heart rate were assessed among seventy-seven 5th-grade participants during a period of rest and while discussing a relational provocation. In addition, teachers reported on participants' ...

The aim of this study was to use magnetic resonance imaging (MRI) to evaluate the three-dimensional geometry and mechanosensory properties of the sigmoid colon. The sigmoid colon was stepwise distended by a water-filled bag in eight subjects. Simultaneous MRI, bag pressure recording and sensory assessment were performed before and after ...

The mechanical properties of the esophagus are important for its function because the esophagus is subjected to changes in wall stress and strains caused by the passage of boli and the action of peristalsis. Electrodes for impedance planimetry and an ultrasound transducer were placed on the probe inside a fluid-filled ...

The current study investigated the relationship between trait forgiveness and cardiovascular reactivity (CVR) and recovery in 99 normotensive participants (mean age=33.8). Cardiovascular parameters were obtained at 2-minute intervals during a 10-minute baseline period and a 20-minute recovery period, and at 1-minute intervals during a 4-minute anger recall task and a ...

A plasma-electrode Pockels cell (PEPC) has been developed for use on the OMEGA extended performance (EP) laser system that can be used in a high-contrast optical switch, as required for isolation of the system from retroreflected pulses. Contrast ratios reliably exceeded 500:1 locally everywhere in the clear aperture. The key ...

Controversies exist regarding the impact of psychological stress on the functioning of the immune system in humans. The aim of the present study, therefore, was to evaluate whether the condition of a pre-exam stress may or not modify resting lymphocyte subsets, as well as blood pressure and heart rate. About ...

The purpose of this study was to compare the cardiovascular responses to different types of mental stress. Ten healthy males performed a mental arithmetic task (MA) on one day and were exposed to white noise (WN, 80dB) on another day. Both the MA and the WN were composed of four ...

OBJECTIVE: We investigated whether personal exposure to particulate matter </= 10 microm in diameter (PM10) contributes to impaired cardiovascular function and increased systemic inflammation and oxidative stress in diabetic patients. METHODS: We monitored 25 patients' personal exposure to PM10 for 24 hours and then measured their heart rate, blood pressure, ...

Mechanical forces have been shown to be important stimuli for the determination and maintenance of cellular phenotype and function. Many cells are constantly exposed in vivo to cyclic pressure, shear stress, and/or strain. Therefore, the ability to study the effects of these stimuli in vitro is important for understanding how ...

Prolonged periods of driving in monotonous situations may lower a driver's activation state as well as increasing their stress level due to the compulsion to maintain safe driving, which may result in an increased risk of a traffic accident. There is therefore an opportunity for technological assessment of driver physiological ...

ABSTRACT: BACKGROUND: In some hypertensive patients, psychological stress makes blood pressure difficult to control and causes physical symptoms such as headache or dizziness. We report the case of a hypertensive man whose psychological stress-induced increase in blood pressure was attenuated by cilnidipine. CASE PRESENTATION: The patient (a 72-year-old man) had ...

The results of experimental studies suggest that estrogen may blunt blood pressure responses to stress, but increase heart rate responses. We investigated whether within-person associations of perceived stress with blood pressure and heart rate during normal working life in 26 premenopausal and 7 postmenopausal women varied according to endogenous estrogen ...

BACKGROUND: The purpose of this study was to investigate the temporal relationship between autonomic changes and pain activation in migraine and tension-type headache induced by stress in a model relevant for everyday office-work. METHODS: We measured pain, blood pressure (BP), heart rate (HR) and skin blood flow (BF) during and ...

Cardiovascular calcification occurs in a variety of location and structure in the heart and the vasculature. Many hypotheses exist in describing local phenomena, however, there is no known global and unifying mechanism to explain all types of cardiovascular soft tissue calcification. The observed calcific changes in the cardiovascular system, however, ...

Identified risk factors for atherosclerosis include diet, age, gender, family history, stress, lifestyle, smoking, diabetes, dyslipidemias, hypertension, and HIV. The mechanistic rationale to explain these associations remains poorly understood. We believe that these seemingly unrelated entities may promote atherosclerosis through a common pathway by inducing adventitial autonomic dysfunction, specifically as ...

Recently, several studies revealed that daily slow-breathing exercise lowered blood pressure and increased baroreflex sensitivity. With this interesting finding, we have been contemplating to design a compact breath-controllable device for relaxation to stress reaction during daily living for home as well as ambulatory use, as a final goal, towards reduction ...

BACKGROUND: The inherent ability of ventricular myocardium to increase its force of contraction in response to an increase in contraction frequency is known as the cardiac force-frequency relation (FFR). This relation can be easily obtained in the stress echo lab, where the force is computed as the systolic pressure/end-systolic volume ...

Both instability and residual articular incongruity are implicated in the development of post-traumatic osteoarthritis (OA) following intra-articular fracture, but currently no information exists regarding cartilage stresses for unstable residual incongruities. In this study, a transversely isotropic poroelastic cartilage finite element model was implemented and validated within physiologically relevant loading ranges. ...

ABSTRACT: BACKGROUND: Possible mechanisms behind psychophysiological hyperreactivity may be located at a cognitive-emotional level. Several personality traits have been associated with increased cardiovascular reactivity. Subjects with white coat hypertension, which may constitute a kind of hyperreactivity, are found to suppress their emotions and adapt to the surroundings to a larger ...

Pulmonary emphysema is usually the result of chronic exposure to cigarette smoke in at risk individuals. To investigate the hypothesis that lung damage in emphysema results from coincident weakening in the structural properties of the tissue and increased mechanical forces--as one explanation of the continued development of pulmonary emphysema after ...

Blood pressure reactivity to mental stress in hypertensives is much higher than in normotensives. The authors' aim in this study was to examine whether different cardiovascular responses can be induced by various stimuli in hypertensive subgroups. The authors matched 10 essential hypertensives (EHs), 10 renal hypertensives (RHs), and 10 normotensives ...

BACKGROUND: Loads acting on scoliotic spines are thought to be asymmetric and involved in progression of the scoliotic deformity; abnormal loading patterns lead to changes in bone and disc cell activity and hence to vertebral body and disc wedging. At present however there are no direct measurements of intradiscal stresses ...

This paper presents an analysis of the peristaltic flow of a couple stress fluid in an asymmetric channel. The asymmetric nature of the flow is introduced through the peristaltic waves of different amplitudes and phases on the channel walls. Mathematical modelling corresponding to a two-dimensional flow has been carried out. ...

Background: The aim of the study was to determine whether the baseline heart rate (HR) and changes in HR after mental stress (MS) can influence endothelial function in syndrome X. Methods: Forty four patients with syndrome X (F/M: 21/23, mean age: 55.4 +/- 10.7 years) were examined. The endothelium-dependent flow-mediated ...

The present study examined the association of cardiac autonomic task-induced reactivity and recovery to preclinical atherosclerosis. Thirty-three men and 33 women aged 24-39 years participated in the ongoing epidemiological Cardiovascular Risk in Young Finns study. The authors measured heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) during ...

Obesity is associated with disturbed cardiovascular responsivity to mental stress, which may mediate psychosocial disease pathways. Whether being aerobically fit is protective against psychophysiological dysfunction in the presence of overweight or obesity is undetermined. Peripheral blood flow, blood pressure, and cardiac responses were measured during a 2-min mental stress task ...

A histology-based methodology was developed and used to determine whether intramural stress and combined monocyte/macrophage density positively correlate within hypertensive bifurcations. Hypertension was induced in Sprague-Dawley rats using Angiotensin II pumps. Analysis focused on mesenteric bifurcations harvested 7 days (n = 4) post implant, but also included normotensive (n = ...

Low wariness in terrestrial island species is attributed to low predation pressure. However, we know nothing of its physiological control and little of its flexibility in the face of predator introductions. Marine iguanas on the Galápagos Islands are an excellent model to study the physiological correlates of low wariness. They ...