View clinical trials related to Nitric Oxide.
Filter by:The American Heart Association (AHA) and American College of Sports Medicine (ASCM) recommend older adults (50≤ age ≤ 80) perform at least 30 minutes of moderate-intensity aerobic exercise on most days ( ≥5 days) of the week. This suggestion arises, in part, from data supporting that regular physical activity reduces the risk of adverse cardiovascular events A portion of these benefits may be from reductions in the incidence and severity of cardiovascular risk factors, including diabetes mellitus, obesity, and hypertension. While this recommendation for physical activity has been in existence for almost 15 years, the rates of obesity in the United States continue to rise and prevalence of sedentarism remains at best unchanged. Researchers have been engaged in investigating novel interventions to designed increase physical activity to reach the recommended activity targets. One promising intervention involves use of inexpensive, easy to use pedometers that allow individuals to objectively track the number of steps taken during a set period of time. Recent data suggest that an average of 10,000 steps/day as measured by a pedometer accurately estimates the activity levels recommended by the AHA, ASCM, and US government public health guidelines. While the benefits of habitual exercise are well-documented, there are no data that demonstrate current recommendations for moderate physical activity in older adults by the ASCM, AHA, and US public health guidelines reduce the risk of adverse cardiovascular events. Interestingly, prior work indicates that pedometer-centered interventions can increase physical activity, suggesting that this type of intervention could potentially lead to cardiovascular benefits. Using validated surrogate markers of cardiovascular risk including brachial artery endothelial function, tonometric measurements of vascular stiffness, and measurements derived from transthoracic echocardiography, we will determine whether increasing the physical activity of sedentary adults to an average of 10,000 steps or more/day translates into improvements in cardiovascular health. This will be determined in the context of a randomized control trial employing a control group, a study group that uses a pedometer alone, and an intervention that couples a pedometer with internet-based motivational messaging software demonstrated in our preliminary data to encourage older adults to reach and exceed the 10,000 steps/day goal.
The fraction of exhaled nitric oxide (FeNO) in expired air is a reliable measure of airway inflammation and has been used as a marker in asthma and other respiratory illnesses such as primary ciliary dyskinesia, bronchopulmonary dysplasia (BPD), liver cirrhosis, chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF). Although, some exquisite bench research experiments have demonstrated stimulation of nitric oxide production in respiratory epithelial cells infected with RSV, there is a paucity of clinical data regarding levels of feNO in viral respiratory illness and specifically RSV. The investigators conducted a pilot study from the fall of 2007 until October of 2009, looking at FeNO levels in RSV infected patients and compared it to non-RSV viral infections. The investigators recruited a total of 28 RSV positive and 1 RSV negative subjects, as well as 4 control subjects. The investigators found FeNO values not statistically significant between the study group (the two-tailed p=0.09, considered not quite significant), but there was a trend of higher FeNO values in the non-RSV group when compared to the RSV group. A larger sample may detect a statistically significance between these 2 groups. Objectives: i. To determine if the fraction of exhaled nitric oxide (feNO) is elevated in hospitalized pediatric patients with viral lower respiratory illness when compared with normal subjects without respiratory symptoms. ii. To determine if there is a difference in feNO level between RSV and non-RSV infection in hospitalized pediatric patients with viral lower respiratory illness. Method of feNO measurement utilized the offline options for preschool children & infants appropriate for age as described in the 2005 Joint Statement of the American Thoracic Society & the European Respiratory Society when discussing tidal breathing techniques with uncontrolled flow rate. The investigators plan that our sample sizes for the RSV+ and control groups will be, by design, three times as large as the RSV- group. In order to achieve 80% power, the investigators will then require 45 control and 45 RSV+ patients, and 15 RSV- patients
Nitric oxide gas is important in regulating blood vessel dilation, and consequently, blood flow. This gas is continuously produced by endothelial cells, which line the blood vessels. This study will examine whether nitrite, a molecule that normally circulates in the blood stream, can also dilate blood vessels. The results of this study may be valuable in developing treatments for people with conditions associated with impaired endothelial production of nitric oxide, including high blood pressure, high blood cholesterol, diabetes, estrogen deficiency, and others. Healthy, non-smoking normal volunteers 21 years of age or older may be eligible for this study. People who lack the enzyme G6PD or cytochrome B5 in their red blood cells may not participate. Absence of these enzymes can lead to episodes of sudden shortness of breath and cyanosis (blueness of the skin due to lack of sufficient oxygen). Participants will undergo the procedures described in study Parts A and B, as follows: - Part A - After numbing the skin, small tubes are placed in the artery and vein at the inside of the elbow of the dominant arm (right- or left-handed) and a small tube is placed in a vein of the other arm. The tubes are used for infusing saline (salt water) and for drawing blood samples. A pressure cuff is placed around the upper part of the dominant arm, and a rubber band device called a strain gauge is also placed around the arm to measure blood flow. When the cuff is inflated, blood flows into the arm, stretching the strain gauge at a rate proportional to the flow. Grip-strength of the dominant arm is measured with a dynamometer to determine maximum grip-strength. Then, several measurements of blood flow, nitrite, hemoglobin, and handgrip are made before and after administration of L-NMMA, a drug that blocks endothelial production of nitric oxide. - Part B - Part A testing is repeated, except that sodium nitrite dissolved in a saline solution is infused into the artery of the forearm for a few minutes before and during the hand-grip exercises. In addition, blood samples are drawn before and after each handgrip exercise to measure methemoglobin, a substance that, at excessive levels, can cause adverse side effects.