Obesity and Free Fatty Acid Flux

为了确定FFA通量是否存在性别和种族差异，并确保非洲裔美国人和白人的充分招募，这项调查是位于马里兰州贝塞斯达的美国国立卫生研究院（NIH）和明尼苏达州奥姆斯特德县的马约诊所之间的合作努力。美国国家卫生研究院所在的大华盛顿特区大都市区有一个大型的非洲裔美国人社区，而奥姆斯特德县90%以上的居民是白人。因此，美国国立卫生研究院将主要研究非裔美国人FFA通量的性别差异。白人FFA通量的性别差异将主要在马约诊所进行研究。将合并两项研究的结果，以确定FFA通量是否存在种族差异。为确保结果归因于种族差异（非裔美国人与白色）而非研究中心差异（NIH与马约），将在NIH招募一些白人，在马约招募一些非裔美国人。 在NIH，将招募50名非洲裔美国人（25 M，25 W）和14名白人（7 M，7 W）。将招募相同数量的正常体重、超重和肥胖受试者。作为门诊病人，参与者将接受两周的体重维持饮食，然后住院两天。在每个住院早晨，将测量静息能量消耗，并输注稳定同位素以测量FFA通量。稳定同位素是元素的天然存在形式，安全且无放射性。在美国国立卫生研究院，7名非洲裔美国男性、14名非洲裔美国女性和3名白色女性已经完成了研究方案，分析正在进行中。

To determine if there are sex and ethnic differences in FFA flux and to ensure adequate enrollment of both African American and whites, this investigation is a collaborative effort between the National Institutes of Health (NIH) in Bethesda, Maryland and the Mayo Clinic in Olmsted County, Minnesota. The greater Washington, DC, metropolitan area, where NIH is located, has a large African-American community whereas over 90% of residents of Olmsted County are whites. Therefore, sex differences in FFA flux in African Americans will be mainly studied at the National Institutes of Health. Sex differences in FFA flux in whites will be mainly studied at the Mayo Clinic. The results of the two studies will be combined to determine if there are ethnic differences in FFA flux. To ensure results are attributable to ethnic differences (African American versus white) rather than site differences (NIH versus Mayo) some whites will be enrolled at NIH and some African Americans at Mayo. At NIH, 50 African-Americans (25M, 25W) and 14 whites (7M, 7W) will be enrolled. Equal numbers of normal weight, overweight and obese subjects will be recruited. As outpatients, participants will be placed on weight maintaining diets for two weeks and then admitted for a two-day hospital stay. On each in-hospital morning, resting energy expenditure will be measured and stable isotopes infused to measure FFA flux. Stable isotopes are naturally occurring forms of elements, which are safe and non-radioactive. At NIH 7 African-American men, 14 African-American women and 3 white women have completed the protocol and analyses are underway.