Search results for "Helium"
showing 10 items of 1689 documents
Gathering of aging and estrogen withdrawal in vascular dysfunction of senescent accelerated mice.
2010
The aim of this work was to characterize a mouse model of experimental menopause and cardiovascular aging that closely reflects menopause in women. Senescence accelerated mouse (SAM)-Resistant type 1 (SAMR1, n=30) and SAM-Prone type 8 (SAMP8, n=30) were separated at 5months of age into three groups: 1) sham-operated (Sham); 2) ovariectomized (Ovx); and 3) ovariectomized chronically-treated with estrogen (Ovx+E2). Contractile responses to KCl (60mM) and thromboxane A(2) were greater in aorta from SAMP8 mice compared with SAMR1 in all groups. Neither ovariectomy nor estrogen replacement modified the contractile responses from SAMR1 mice. Conversely, in Ovx SAMP8 the increased maximal contract…
Paradoxical effect of l-arginine: Acceleration of endothelial cell senescence
2009
We have recently shown that inhibition of nitric oxide (NO) synthesis by asymmetrical dimethylarginine (ADMA) accelerated endothelial cell (EC) senescence which was prevented by coincubation with L-arginine; however the effect of long-term treatment of l-arginine alone on senescence of ECs have not been investigated. Human ECs were cultured in medium containing different concentrations of L-arginine until senescence. L-Arginine paradoxically accelerated senescence indicated by inhibiting telomerase activity. Moreover, L-arginine decreased NO metabolites, increased peroxynitrite, and 8-iso-prostaglandin F(2alpha) formation. In old cells, the mRNA expression of human amino acid transporter (h…
Telomere length and cardiovascular disease
2010
SummaryTelomeres are structures composed of deoxyribonucleic acid repeats that protect the end of chromosomes, but shorten with each cell division. They have been the subject of many studies, particularly in the field of oncology, and more recently their role in the onset, development and prognosis of cardiovascular disease has generated considerable interest. It has already been shown that these structures may deteriorate at the beginning of the atherosclerotic process, in the onset and development of arterial hypertension or during myocardial infarction, in which their length may be a predictor of outcome. As telomere length by its nature is a marker of cell senescence, it is of particula…
In vivo Microperfusion Studies: Validation and Potential Uses in Critical Patients
2010
Recent studies have suggested an increase in sepsis rates, this increase is due to several factors, such as the increase in the average age of the population, the growing number of invasive procedures and use of immunosuppressive drugs. The increase in sepsis incidence causes localized endothelial damage in various regions, it was this aspect that led us to focus the studies on the endothelium and in vivo microperfusion investigations in order to contribute to the scientific knowledge in this field. The present study will meticulously analyze this current and complex issue that affects on a daily basis, everyone involved in critical patient care.
Modulatory Role of Endothelial and Nonendothelial Nitric Oxide in 5-Hydroxytryptamine-induced Contraction in Cerebral Arteries after Subarachnoid Hem…
1996
OBJECTIVE : Endothelial dysfunction is claimed to play a role in the pathogenesis of delayed cerebral vasospasm after subarachnoid hemorrhage (SAH). We have examined the effect of experimental SAH on the modulatory action of endothelial and nonendothelial nitric oxide (NO) in the contractile response of goat middle cerebral artery to 5-hydroxytryptamine (5-HT). METHODS : We compared the 5-HT-induced contractile responses of cerebral arteries from control goats and from goats with SAH that had been experimentally induced 3 days earlier by delivery of autologous arterial blood into the subarachnoid space. Contractile responses were examined by recording the isometric tension in isolated cereb…
RUOLO DELLA LEPTINA NELLE CELLULE EPITELIALI NASALI
2014
Leptin is involved in the lung epithelial homeostasis. Its role in the nasal tract is largely unknown. Allergic rhinitis (AR) is induced by the allergen exposure leading to a consequential structural abnormalities in the nasal epithelium. Topical corticosteroids are recommended as first-line therapy in AR. Parietaria pollen is one of the most important allergenic sources in the southern Europe. In vitro on human nasal epithelial cell line RPMI 2650, we aimed to determine whether allergen stimulation acts on leptin/leptin receptor pathway and how Fluticasone Furoate (FF) influences this pathway. The effects of the major allergen rPar j 1, of FF, of leptin and of TGFβ1 on cell proliferation a…
Recent Patents on Oxidative Stress-Related Biomarkers in Chronic Heart Failure: The Central Role of Endothelium and Myeloperoxidase
2013
Endothelial cells are key modulators of multiple physiological processes, and their impairment may result in the generation of endothelial dysfunction and ultimately cardiovascular diseases. Under physiologic conditions, reactive oxygen and nitrogen mediators of endothelial cells act to propagate signals driven by different stimuli, by forming molecules with a longer half-life like hydrogen peroxide. Reactive oxygen species (ROS) are constantly produced as a consequence of aerobic metabolism. Under physiologic conditions, their tendency to cause oxidative damage is counterbalanced by the action of antioxidants or oxidant-scavenging enzymes. An imbalance in favour of oxidants leads to oxidat…