In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Epidemiological prospective data on cardiovascular (CV) events in elderly subjects from Mediterranean populations are lacking. We aimed to investigate 15-year incidence of CV events and to evaluate the association with CV risk factors in an elderly Mediterranean population.', 'The population of a small Sicilian village were enrolled, visited and a blood sample was drawn at baseline. CV events were recorded in the 15 years of follow-up. From 1351 subjects (75% of the resident population); 315 were in the age range 65-85 years; 266 subjects free from CV disease were analysed. Seventy-seven CV events were recorded in 73 out of 266 subjects, with a 19.7% rate (in 10 years). Hypertension (HTN) (hazards ratio=2.1) and diabetes mellitus (DM) (hazards ratio=1.8) were independently associated with CV events. Subjects with both DM and HTN showed a lower survival free of CV events compared to those with DM or HTN.\Question: Are hypertension and diabetes mellitus associated with cardiovascular events in the elderly without cardiovascular disease . Results of a 15-year follow-up in a Mediterranean population?
In a 15-year follow-up of an elderly Mediterranean population free from CV disease, diabetes mellitus and hypertension were related to CV events. The control of risk factors in the elderly needs to be reinforced to achieve better results in terms of CV prevention.

Context: Perls' stain is routinely used to demonstrate iron in liver biopsies. We tested the hypothesis that it may be unnecessary in cases, where no iron or another similar pigment was seen on the routine hematoxylin and eosin (H and E) stained section.", "The aim of this study was to evaluate the efficiency of H and E stain in demonstrating iron in liver biopsies as well as to determine the possibility of replacing Perls' stain with H and E stain.", "Two hundred pairs of slides of liver biopsies were taken from the archival files of the Department of Pathology from 2006 to 2011. Perls' and H and E slides were independently reviewed for the presence of iron.", "Hundred and one cases showed the presence of iron using H and E stain. 84 of 86 cases showed positive iron using both Perls' and H and E stains. Seventeen cases were positive using H and E stain but negative with Perls'. Only two cases did not show the presence of iron using H and E stain. Ninety-seven cases were negative using both Perls' and H and E stains. H and E stain showed a sensitivity, specificity, accuracy, positive predictive valve, and negative predictive value of 97.67%, 85.08%, 90.5%, 83.16%, and 97.98%, respectively.\Question: Do hematoxylin and eosin stain shows a high sensitivity but sub-optimal specificity in demonstrating iron pigment in liver biopsies?
We demonstrate that the H and E stain is a sensitive method to detect iron pigment in liver biopsies, particularly when present in large quantities. A negative H and E stain might obviate the need for extra Perls' staining, thus saving costs and shortening report turn-around times.

Context: Although estrogen replacement therapy has been associated with reduction of cardiovascular events in postmenopausal women, the mechanism for this benefit remains unclear. Because nitric oxide (NO) is considered an important endothelium-derived relaxing factor and may function to protect blood vessels against atherosclerotic development, we investigated the acute effects of physiological levels of estrogen on NO release from human internal thoracic artery endothelia and human arterial endothelia in culture.', 'We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase activity in human endothelial cells by acting on a cell-surface receptor. NO release was measured in real time with an amperometric probe. 17beta-Estradiol exposure to internal thoracic artery endothelia and human arterial endothelia in culture stimulated NO release within seconds in a concentration-dependent manner. 17beta-Estradiol conjugated to bovine serum albumin also stimulated NO release, suggesting action through a cell-surface receptor. Tamoxifen, an estrogen receptor inhibitor, antagonized this action. We further showed with the use of dual emission microfluorometry that 17beta-estradiol-stimulated release of endothelial NO was dependent on the initial stimulation of intracellular calcium transients.\Question: Do cell-surface estrogen receptors mediate calcium-dependent nitric oxide release in human endothelia?

Physiological doses of estrogen immediately stimulate NO release from human endothelial cells through activation of a cell-surface estrogen receptor that is coupled to increases in intracellular calcium.