Search results for " STRESS"
showing 10 items of 3936 documents
Dithiothreitol prevents age-associated decrease in oocyte/conceptus viability in vitro.
1998
The present study was designed to ascertain whether the negative effects on reproductive potential of post-ovulatory ageing in vitro of oocytes can be prevented by antioxidant therapy. Mouse metaphase II (MII) oocytes were aged in vitro for 12 h prior to insemination in the presence of varying concentrations of L-ascorbic acid, 6-methoxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), L-cystine dihydrochloride, ethylenediaminetetraacetic acid (EDTA), beta-mercaptoethanol and DL-dithiothreitol (DTT). In-vitro ageing of oocytes was associated with lower fertilization rate, higher proportion of concepti exhibiting cellular fragmentation at 24 h post-insemination and lower percentage of…
Computational fluid dynamics simulation to evaluate aortic coarctation gradient with contrast-enhanced CT
2014
Coarctation of aorta (CoA) is a narrowing of the aorta leading to a pressure gradient (Delta P) across the coarctation, increased afterload and reduced peripheral perfusion pressures. Indication to invasive treatment is based on values of maximal (systolic) trans-coarctation Delta P. A computational fluid dynamic (CFD) approach is herein presented for the non-invasive haemodynamic assessment of Delta P across CoA. Patient-specific CFD simulations were created from contrast-enhanced computed tomography (CT) and appropriate flow boundary conditions. Computed Delta P was validated with invasive intravascular trans-CoA pressure measurements. Haemodynamic indices, including pressure loss coeffic…
Frontal Electroencephalogram Alpha Asymmetry during Mental Stress Related to Workplace Noise
2021
This study aims to investigate the effects of workplace noise on neural activity and alpha asymmetries of the prefrontal cortex (PFC) during mental stress conditions. Workplace noise exposure is a pervasive environmental pollutant and is negatively linked to cognitive effects and selective attention. Generally, the stress theory is assumed to underlie the impact of noise on health. Evidence for the impacts of workplace noise on mental stress is lacking. Fifteen healthy volunteer subjects performed the Montreal imaging stress task in quiet and noisy workplaces while their brain activity was recorded using electroencephalography. The salivary alpha-amylase (sAA) was measured before and immedi…
Antiapoptotic effect of calcitonin gene-related peptide on oxidative stress-induced injury in H9c2 cardiomyocytes via the RAMP1/CRLR complex.
2005
Calcitonin gene-related peptide (CGRP) plays an important role in the mediation of protective effects observed in situations such as ischemic preconditioning in rat hearts. In this study, we investigated in H9c2 rat cardiomyoblasts if the protective effect of CGRP could be linked to an inhibitory effect on the apoptotic pathway. We also determined the specificity of observed effects by treatment with adrenomedullin (ADM) in stress conditions generated by 100 microM hydrogen peroxide. Using MTT assays, we demonstrate that a pretreatment with CGRP decreases by half the loss of cell viability induced by H(2)O(2). CGRP inhibits phosphatidylserine externalization, caspase 3 activation and DNA fr…
Genetic bases of urinary albumin excretion and related traits in hypertension
2010
Epidemiological as well as animal studies have recognized the potential role of genetic factors in the development of microalbuminuria and related traits (renal insufficiency, end-stage renal disease and nephroangiosclerosis) in hypertension. To unravel genetic variants of susceptibility, candidate gene, linkage and genome wide scan analysis has been used. In spite of the great efforts that have been made in the field, sound knowledge about the major genetic variants causing the susceptibility to develop renal damage in hypertension is scarce, since many associations were not replicated or only showed association in a certain subgroup of patients. Looking initially at genes of the most impo…
Adaptation of neuronal cells to chronic oxidative stress is associated with altered cholesterol and sphingolipid homeostasis and lysosomal function
2009
Chronic oxidative stress has been causally linked to several neurodegenerative disorders. As sensitivity for oxidative stress greatly differs between brain regions and neuronal cell types, specific cellular mechanisms of adaptation to chronic oxidative stress should exist. Our objective was to identify molecular mechanisms of adaptation of neuronal cells after applying chronic sublethal oxidative stress. We demonstrate that cells resistant to oxidative stress exhibit altered cholesterol and sphingomyelin metabolisms. Stress-resistant cells showed reduced levels of molecules involved in cholesterol trafficking and intracellular accumulation of cholesterol, cholesterol precursors, and metabol…
Hyperglycemia and oxidative stress in cultured endothelial cells – a comparison of primary endothelial cells with an immortalized endothelial cell li…
2012
Diabetes mellitus is a major risk factor for the development of cardiovascular disease and oxidative stress plays an important role in this process. Therefore, we investigated the effects of hyperglycemia on the formation of reactive oxygen species (ROS) and nitric oxide/cGMP signaling in two different endothelial cell cultures. Human umbilical vein endothelial cells (HUVEC) and EA.hy 926 cells showed increased oxidative stress and impaired NO-cGMP signaling in response to hyperglycemia. The major difference between the two different cell types was the dramatic decrease in viability in HUVEC whereas EA.hy cells showed rather increased growth under hyperglycemic conditions. Starvation led to…
Exploring User-Related Drivers of the Early Acceptance of Certified Digital Stress Prevention Programs in Germany.
2020
Electronic mental health services represent innovative instruments to increase the dissemination of stress programs in primary prevention. However, little is known about facilitators of their uptake. This study aimed to explore determinants of the acceptance of centrally certified digital stress coping programs and preferences for service delivery modes among adult members of German statutory health insurances. Participants completed a multi-construct 45-item questionnaire covering acceptance of digital stress prevention (behavioral use intention) and potential predictors we assessed using hierarchical regression analysis—(1) socio-demographic variables and time spent online, (2) openness …
Repeated restraint stress suppresses neurogenesis and induces biphasic PSA-NCAM expression in the adult rat dentate gyrus
2003
Chronic restraint stress has been shown to induce structural remodelling throughout the interconnected dentate gyrus-CA3 fields. To find out how this stressor affects the rate of adult hippocampal neurogenesis, we subjected rats to acute or chronic restraint stress and assessed the proliferation, survival and differentiation of newly born cells in the dentate gyrus. We also examined polysialylated neural cell adhesion molecule expression, a molecule normally expressed in immature neurons and important for morphological plasticity. The results show that acute restraint stress did not change either the proliferation of dentate gyrus precursor cells or the expression of polysialylated neural c…