Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “STRESS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,243 records · Page 69Linked to original sources

The effect of a hydroxyapatite-reinforced polyethylene stress distributor in a dental implant on compressive stress levels in surrounding bone.

This study investigated various designs of stress breakers incorporated into the dental implant using 3-D finite element analysis. These designs employed hydroxyapatite-reinforced polyethylene (HRP), a material capable of inducing osseointegration. The most successful design was that of a dental implant with a peripheral HRP component that was in direct contact with the bone surrounding the neck of the implant. This design lowered the compressive stress values in bone around the neck of the implant. Attempts were also made to optimize this design.

Alveolar Process↗

[Acute stress disorder and posttraumatic stress disorder after motor vehicle accidents].

OBJECTIVE: We examined the rates of and factors associated with the development of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) after motor vehicle accidents (MVAs). METHOD: Forty hospitalized patients who had orthopedic injuries after MVAs and 26 hospitalized patients who had orthopedic injuries without a MVA were included in the study. One month after the MVA, the General Health Questionnare (GHQ) Hamilton Depression Rating Scale (HDRS), Multidimensional Scale of Perceived Social Support (MSPSS), Peritraumatic Dissociative Experiences Questionnare (PDEQ) and sociodemographic data questionnaire were given to all patients. At 3 and 6 months follow-up the Clinician Administered PTSD Scale (CAPS), HDRS, GHQ, and a questionnaire concerning medical problems caused by the accident along with economic and legal problems were applied. RESULTS: 20% of the inpatients in the MVA group developed ASD in the 1st month, 30% developed PTSD in the 3rd month and 17% developed PTSD in the 6th month, while in the control group none of the patients developed either ASD or PTSD. The MVA group had higher mean GHQ, HDRS and CAPS scores than the controls at the 1st, 3rd and the 6th months of follow-up. CONCLUSION: Serious and long-term psychiatric problems are seen after MVAs. Early intervention and rehabilitation are needed for the risk groups determined.

Accidents, Traffic↗

[The effect of teeth arrangement in maxillary complete denture on the stress distribution of bone tissue--photoelastic stress analysis].

In this paper, we make a study about the effects of 6 different kind of arrangement of the 1st molar in maxillary complete denture on the stress distribution of bone tissue. In intercuspation position, it is well-distributed when the artificial teeth are arranged on the top of alveolar ridge. There are stress concentration in the bone tissue. When the long axis of the teeth incline bucally or the teeth migrate away from the ridge center line. When the ridges relation is disharmonious, it is better that the teeth incline do not over 30 degrees buccally and the teeth migration do not over 5 mm horizontally.

Alveolar Process↗

Endogenous opioids, stress induced analgesia, and posttraumatic stress disorder.

The hypothesis that the animal model of inescapable shock (IES) is an appropriate model for posttraumatic stress disorder (PTSD) predicts that re-exposure to a traumatic stressor will precipitate opioid-mediated stress-induced analgesia in people with PTSD. Eight Vietnam veterans with PTSD and eight matched veterans without PTSD viewed a combat videotape under naloxone and placebo conditions in a randomized double-blind crossover design. In the placebo condition, but not after naloxone, the PTSD subjects reported a 30 percent decrease in pain intensity ratings of standardized heat stimuli after the combat videotape. Point biserial correlations revealed that change in pain perception was the most highly correlated with PTSD of all variables tested, including biochemical, physiological, and self-report. These results suggest that a centrally mediated opioid response to traumatic stimuli is an important feature of PTSD. Possible implications of this finding for the psychobiology of PTSD are discussed.

Endorphins↗

Stressful life situations and perception of stress in black and Indian duodenal ulcer patients.

The stressful life situations of 87 patients with endoscopically confirmed recent duodenal ulceration (DU) were compared with those of 75 essentially orthopaedic non-DU controls. Results indicated a statistically significant difference in the reporting of low income and dissatisfaction, including tensions related to considerable responsibility in the work situation but no authority, by both Indian and black DU patients. Indian DU patients reported significantly more family conflict and problems than controls, while black DU patients reported living in single hostels or in split families to a significantly greater degree than controls. Overall, DU patients experienced significantly greater stress in more areas of their lives than controls.

Adult↗

[The correlation of the severity of stress urinary incontinence with static and stress urethral pressure profiles].

The urethral pressure profile (UPP) at rest and under stress was recorded by means of double lumen microtip transducer catheter in 58 females with stress urinary incontinence (SUI). The patients were divided into three groups including mild to moderate SUI patients (n = 29, group 1), severe SUI patients (n = 16, group 2) and very severe SUI patients (n = 13, group 3) according to a one-hour pad test. The functional urethral length (FUL) was divided into four equal lengths and the pressure transmission ratio (PTR) was calculated for each quartile for each female. We examined the correlation of the severity of SUI with urethral pressure parameters: maximum urethral closure pressure (MUCP) at rest and functional urethral length (FUL) at rest and PTR. SUI patients showed a negative association between the severity of SUI and MUCP, but no significant differences in the FUL were seen between the different groups. PTR was shown to be similar in order for all groups of SUI patients showing a linear decrease in the value of the PTR along the FUL. However, we found a negative association between the severity of SUI and PTR (P < 0.05) at the middle part of the FUL (Q3). These findings indicate that there are more defective distal sphincter mechanisms in severe SUI patients than in mild to moderate SUI patients. There was an overlap between the different groups in both MUCP and PTR at the middle urethra (Q3), suggesting that other parameters are related with the severity of SUI.

Adult↗

A review of polymerization contraction: the influence of stress development versus stress relief.

The insertion of bonded resin composites into cavity preparations leads to a competition between polymerization contraction forces and the strength of bonds to tooth structure. The degree of stress development can be controlled, to some extent, by the cavity design (C-factor), the use of bases, the size, shape, and position of increments of composite resins placed in the cavity, and whether the resin is light- or chemically cured. Stress relief can be accomplished by maintaining the C-factor as low as possible, using chemical-curing resins, low modulus liners, and, over time, by water sorption. A thorough understanding of these principles permits clinicians to exercise more control over these variables, thereby improving the quality of their bonded restorations.

Absorption↗

Post-tsunami stress: a study of posttraumatic stress disorder in children living in three severely affected regions in Sri Lanka.

At 3 to 4 weeks after the December 2004 tsunami disaster we assessed symptoms of posttraumatic stress disorder (PTSD) in 264 children who lived in severely affected coastal communities in Manadkadu (northern coast), Kosgoda (western coast), and Galle (southern coast) in Sri Lanka. The prevalence rate of tsunami-related posttraumatic stress disorder (PTSD) (ignoring the time criterion) ranged between 14% and 39% and an additional 5% to 8% had PTSD unrelated to the tsunami. The PTSD symptoms were explained by the severity of the trauma exposure and family loss, as well as previous traumatic events. The results confirm the relevance of the individual history of traumatic events for the genesis of PTSD and indicate a high need of mental health assistance among the tsunami-affected children in Sri Lanka.

Adolescent↗

Urodynamic parameters in patients with slight and severe genuine stress incontinence: is the stress profile useful?

This study evaluates the usefulness of the urethral pressure profile (UPP) parameters in assessing the severity of genuine stress incontinence (GSI). Functional length (FL), maximum urethral closure pressure (MUCP), pressure transmission ratio (PTR), residual area at stress (RAS), number of patients with incontinent spikes (IS), and distribution of IS on UPP were determined in supine and standing position for 54 patients (group 1) with a 1-hour pad test < 2 g and compared with the values of 63 patients (group 2) with a 1-hour pad test > 2 g. The results were similar: FL (supine: 24 mm +/- 6/26 mm +/- 7 [P:0.2]; standing: 26 mm +/- 8/24 mm +/- 11 [P:0.5]); MUCP (supine: 51 cm H2O +/- 23/47 cm H2O +/- 20 [P:0.3]; standing: 45 cm H2O +/- 21/38 cm H2O +/- 18 [P:0.1]); and PTR (supine: 83% +/- 27/84% +/- 31 [P:0.9]; standing: 81% +/- 25 and 88% +/- 27 [P:0.3]). But the RAS was lower (supine: 502 mm2 +/- 497/246 mm2 +/- 268 [P < 0.009]; standing: 500 mm2 +/- 534/271 mm2 +/- 306 [P < 0.05]) in group 2. If the percentage of patients with IS was higher (supine: 57/93% [P < 0.001]; standing: 54/84% [P < 0.01]) in group 2, the distribution of IS over the entire FL demonstrated no differences between group 1 and 2. In conclusion, except for the RAS, standard UPP parameters cannot be considered determinant in assessing the severity of GSI.

Cough↗

Stress-induced eating: an alternative method for inducing ego-threatening stress.

This study was designed to assess the effectiveness of a modified Stroop test as a method of inducing ego-threatening stress in dieters. Twenty females completed a Stroop task and watched a fearful film, and then consumed ice cream, ad libitum, under the guise of a tasting-test. It was predicted that the Stroop task would trigger greater consumption of ice cream than a fearful film, and that this effect would be more pronounced for binge-eaters than non-binge-eaters. More ice cream was consumed following the Stroop task, however both binge-eaters and non-binge-eaters consumed more ice cream after the Stroop task than the film-task. This data suggests that the ego-threatening Stroop test has potential as a standardized method for use in studies of stress-induced eating.

Adolescent↗

Mammalian small stress proteins protect against oxidative stress through their ability to increase glucose-6-phosphate dehydrogenase activity and by maintaining optimal cellular detoxifying machinery.

The protective activity of small stress proteins (sHsp) against H2O2-mediated cell death in the highly sensitive murine L929 fibroblast has been analyzed. We report here that the human Hsp27- and murine Hsp25-mediated rise in glutathione (GSH) levels as well as the maintenance of this redox modulator in its reduced form was directly responsible for the protection observed at the level of cell morphology and mitochondrial membrane potential. sHsp expression also buffered the increase in protein oxidation following H2O2 treatment and protected several key enzymes against inactivation. In this case, however, the protection necessitated both an increase in GSH and the presence of sHsp per se since the pattern of protection against protein oxidation mediated by a simple GSH increase was different from that induced by sHsp expression. Among the enzymes analyzed, we noticed that sHsp significantly increased glucose-6-phosphate dehydrogenase (G6PD) activity and to a lesser extent glutathione reductase and glutathione transferase activities. Moreover, an increased GSH level was observed in G6PD-overexpressing L929 cell clones. Taken together our results suggest that sHsp protect against oxidative stress through a G6PD-dependent ability to increase and uphold GSH in its reduced form and by using this redox modulator as an essential parameter of their in vivo chaperone activity against oxidized proteins.

Animals↗

The endoplasmic reticulum stress-responsive protein GRP78 protects neurons against excitotoxicity and apoptosis: suppression of oxidative stress and stabilization of calcium homeostasis.

The 78-kDa glucose-regulated protein (GRP78) is localized in the endoplasmic reticulum (ER), and its expression is increased by environmental stressors in many types of nonneuronal cells. We report that levels of GRP78 are increased in cultured rat hippocampal neurons exposed to glutamate and oxidative insults (Fe2+ and amyloid beta-peptide) and that treatment of cultures with a GRP78 antisense oligodeoxynucleotide increases neuronal death following exposure to each insult. GRP78 antisense treatment enhanced apoptosis of differentiated PC12 cells following NGF withdrawal or exposure to staurosporine. Pretreatment of hippocampal cells with 2-deoxy-d-glucose, a potent inducer of GRP78 expression, protected neurons against excitotoxic and oxidative injury. GRP78 expression may function to suppress oxidative stress and stabilize calcium homeostasis because treatment with GRP78 antisense resulted in increased levels of reactive oxygen species and intracellular calcium following exposure to glutamate and oxidative insults in hippocampal neurons. Dantrolene (a blocker of ER calcium release), uric acid (an antioxidant), and zVAD-fmk (a caspase inhibitor) each protected neurons against the death-enhancing action of GRP78 antisense. The data suggest that ER stress plays a role in neuronal cell death induced by an array of insults and that GRP78 serves a neuroprotective function.

Animals↗

Sensing stress and responding to stress.

Heat shock protein gene expression is enhanced by proteotoxic stress, i.e., by conditions favoring protein unfolding. This upregulation of heat shock protein genes is mediated by heat shock transcription factor HSF1. A mechanism, the details of which are still elusive, senses adverse conditions and causes HSF1 to oligomerize and to acquire DNA-binding ability. The DNA-binding form of HSF1 then undergoes further conformational changes that render it transcriptionally competent. The current model in which heat shock protein 70 acts both as sensor of stress and as negative regulator of HSF1 oligomerization as well as alternative models involving additional protein factors are discussed.

DNA-Binding Proteins↗

Effects of exercise intensity and environmental stress on indices of oxidative stress and iron homeostasis during exercise in the horse.

The effects of prolonged variable-intensity and short-term high-intensity exercise on indices of oxidative stress and iron homeostasis were compared in six fit horses under cool [20 degrees C, 40% relative humidity (RH)] or hot/humid (30 degrees C, 80% RH) environmental conditions. The exercise protocols were designed to simulate equine competition, including racing (intense exercise) or the speed and endurance phase of a 3-day event (prolonged exercise). Increased plasma concentrations of lipid hydroperoxides and haemolysate concentrations of oxidised glutathione (GSSG) were measured within 30 min of the completion of exercise, indicating production of reactive oxygen species (ROS) and lipid membrane peroxidation. The horses were unable to complete the prolonged exercise protocol at high temperature and humidity. This coincided with higher maximal values of lipid hydroperoxides [138.2 (17.7) microM and GSSG [110.6 (18.2) microM], compared to high-intensity [105.2 (14.9) microM and 63.6 (8.6) microM, respectively] or prolonged [100.7 (18.7) microM and 86.2 (9.1) microM, respectively] exercise performed under cooler environmental conditions. Significant correlations were found between the duration of the final stage of exercise during hot/humid environmental conditions and increased levels of lipid hydroperoxides (r = 0.85), GSSG (r = 0.94), xanthine (r = 0.92) and uric acid (r = 0.96). Exercise also decreased the iron (Fe)-binding antioxidant activity of the plasma and increased the total plasma Fe levels, although this was only significant for prolonged exercise in ambient conditions. There was no detectable free Fe in the plasma at any stage of exercise. Other changes in biochemical parameters had returned to pre-exercise levels within 24 h after exercise. The results show that exercise can induce changes in biochemical parameters that are indicative of oxidative stress in the fit horse and that this was, exacerbated during exercise at high temperature and humidity.

Animals↗

[Significance of psychological stress, absence of stress and resources for health promotion at the workplace].

Stress is defined as a lasting, averse situation, the avoidance of which appears to be subjectively important and where the individual is not sure of having enough ability to control it. Eustress, contrary to this, is characterized by the individual's confidence of being able to master given demands successfully. Therefore eustress can not equated with stress. One may assume that the repeated experience of mastering given demands constitutes a resource in coping with stressors. Empirical findings have shown psychic stressors to be systematically linked with individual discomfort preceding clinical symptoms. Therefore alterations to psychic stressors may be a mean of prophylaxis. Data from surveys on blue-collar workers moreover have suggested that two working conditions themselves may provide resources for coping with stressors: decision latitude and social support. Hence enlarging decision latitude and enhancing social support may be possibilities for prevention, especially in such cases, where stressors cannot (yet) be directly changed.

Adaptation, Psychological↗

Assessment of myocardial perfusion during cold stress using thallium-201 scintigraphy in diabetic patients with abnormal changes in left ventricular function during cold stress.

Eleven type-I (insulin-dependent) diabetic patients with abnormal changes in left ventricular function in response to cold stress (CS) were investigated to try and determine the cause of these abnormal responses. Resting M-mode echocardiography demonstrated that all 11 patients had normal left ventricular dimensions and wall motion, thereby excluding overt cardiomyopathy. Thallium-201 scintigraphy was used to assess myocardial perfusion during CS and eight patients were found to have perfusion defects during stress which persisted in four. It is possible that CS unmasks evidence of myocardial ischemia but it is also possible that the abnormal responses to CS reflect altered vasomotor reactivity in the diabetic patient, producing coronary spasm. Left ventricular function may be influenced by many factors in diabetes and an abnormal CS test may not necessarily indicate structural disease. Such tests, however, may help in the further understanding of the pathophysiology of heart disease in diabetes.

Adult↗

Oxidative stress, ER stress, and the JNK pathway in type 2 diabetes.

Pancreatic beta-cell dysfunction and insulin resistance are observed in type 2 diabetes. Under diabetic conditions, oxidative stress and ER stress are induced in various tissues, leading to activation of the JNK pathway. This JNK activation suppresses insulin biosynthesis and interferes with insulin action. Indeed, suppression of the JNK pathway in diabetic mice improves insulin resistance and ameliorates glucose tolerance. Thus, the JNK pathway plays a central role in pathogenesis of type 2 diabetes and may be a potential target for diabetes therapy.

Animals↗

Trace metal concentrations and susceptibility to oxidative stress in the polychaete Sabella spallanzanii (Gmelin) (Sabellidae): potential role of antioxidants in revealing stressful environmental conditions in the Mediterranean.

The polychaete Sabella spallanzanii (Gmelin) (Sabellidae) is a widely distributed species throughout the Mediterranean where it is commonly found in sheltered shallow areas and up to 30 m depth in more exposed waters. The sedentary habit, the filter-feeding behavior and its capability to colonize disturbed environments such as harbors, suggest the potential utility of this organism as a bioindicator in environmental monitoring programs. The aim of this work was a preliminary characterization of S. spallanzanii, integrating chemical data on trace metal concentrations with the biochemical analysis of antioxidant defenses which play an important role in mediating responses and adaptation to stressful environmental conditions. Organisms were collected in four locations of the Adriatic and Tyrrhenian Sea, characterized by a moderate impact or influenced by organic enrichment or sulphuric emissions. Trace metal concentrations (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) were comparable to those of other invertebrate species and quite typical for unpolluted environments. Analyses of individual antioxidants (superoxide dismutase, catalase, glutathione peroxidases, glutathione S-transferases, glutathione reductase) were integrated with measurement of the total oxyradical scavenging capacity toward specific forms of ROS; the TOSC assay, quantifying the overall capability of a tissue to neutralize specific reactive oxygen species provide a more integrated picture of the balance between prooxidant factors and antioxidant defenses, with important indications about the role of different ROS in appearance of oxidative disease. The antioxidant profile was influenced by the different physiological functions of the analyzed tissues, namely the branchial crown, involved in filtration of large volumes of seawater, and the thorax where digestive processes occur. The analysis of antioxidant defenses revealed significant variations in polychaetes from various sampling sites suggesting the influence of specific environmental conditions like those limiting oxygen availability. Our results confirm the role of antioxidants in adaptation to stressful environmental conditions and their importance in ecotoxicological studies for the sensitivity in revealing the occurrence of biological disturbance.

Animals↗