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101.
Leptin in postmenopausal women: influence of hormone therapy, insulin, and fat distribution 总被引:3,自引:0,他引:3
Gower BA Nagy TR Goran MI Smith A Kent E 《The Journal of clinical endocrinology and metabolism》2000,85(5):1770-1775
Whether use of hormone-replacement therapy (HRT) influences menopause-related changes in body weight is unclear. HRT may affect energy balance by influencing synthesis of the adipocyte-derived hormone leptin. The objectives of this study were to: 1) identify factors influencing circulating leptin in postmenopausal women; 2) determine whether HRT influences serum leptin after adjusting for confounding factors; and, 3) identify potential independent effects of HRT or leptin on resting energy expenditure (REE). Subjects were 54 postmenopausal women, 45-55 yr old, 35 of whom used HRT (estrogen plus progestin). Total and regional body composition and fat distribution were determined by dual-energy x-ray absorptiometry and computed tomography; fasting serum leptin and insulin, by RIA; and REE, by indirect calorimetry. Stepwise multiple linear regression analysis indicated that serum leptin could best be predicted from total fat mass, fasting serum insulin, and total lean mass [log leptin = 1.08 x log fat mass) + (0.46 x log insulin) + (-1.25 x log lean mass) + 1.88; model R2 = 0.78, P < 0.001]. Multiple linear regression analysis indicated that visceral fat was independently related to leptin (parameter estimate = 0.23, P < 0.05), after adjusting for s.c. abdominal fat and leg fat, as well as lean mass and insulin. After adjusting for total fat mass, total lean mass, and fasting insulin, serum leptin did not differ between users and nonusers of HRT (21.7 +/- 1.0 vs. 20.2 +/- 1.3 ng/mL, P = 0.369, adjusted mean +/- SE, respectively). Serum estradiol was inversely correlated with (adjusted) leptin in non-HRT users (r = -0.50), suggesting that ovarian senescence may lead to an increase in leptin. Multiple linear regression analysis indicated that REE (adjusted for fat mass, fat-free mass, and ethnicity) was not associated with leptin (P = 0.298) or hormone use status (P = 0.999; 1323 +/- 31 vs. 1316 +/- 42 kcal/day, adjusted mean +/- SE for users and nonusers, respectively). These results indicate that, in postmenopausal women: 1) total fat mass, lean mass, and fasting insulin, but not HRT, are significant determinants of serum leptin; 2) visceral and s.c. fat contribute to serum leptin; and, 3) neither HRT nor leptin is independently related to REE. 相似文献
102.
Kent McIntosh Sterett H. Mercer Rhonda N. T. Nese Adam Ghemraoui 《Prevention science》2016,17(8):992-1001
The purpose of this study was to examine the extent to which distinct patterns of fidelity of implementation emerged for 5331 schools over a 5-year course of implementing school-wide positive behavioral interventions and supports (SWPBIS). We used latent class analysis to classify schools based on their likelihood of implementing SWPBIS with fidelity each year, then assessed school and district predictors of classifications. A four-class solution fit the model well, with two patterns of sustained implementation (Sustainers and Slow Starters) and two patterns of practice abandonment (Late Abandoners and Rapid Abandoners). Significant predictors of group membership included grade levels served, enrollment, proportion of schools implementing SWPBIS in the district (“critical mass”), and size of the implementation cohort (“community of practice”). Elementary schools, larger schools, schools in districts with more schools already implementing SWPBIS, and those starting within a larger initial district cohort were more likely to be in the sustaining classes. Results are discussed in terms of understanding patterns of implementation in schools to enhance sustained implementation of school practices. 相似文献
103.
Tomomi Koizumi Peter J. Fitzgerald Yasuhiro Honda Stephen G. Ellis Kenneth Kent Steven L. Martin Charles L. Brown A.R. Zaki Masud John B. Patterson Joel Greenberg Mark Friedman Takahiro Uchida Gregg W. Stone 《Cardiovascular Revascularization Medicine》2010,11(3):140-148
BackgroundAlthough effective coverage of coronary diffuse in-stent restenosis (ISR) lesions has warranted the use of multiple drug-eluting stents, the vessel response to paclitaxel-eluting stent (PES) overlap is not fully understood.Methods and materialsIn the TAXUS-V ISR, i.e., comparing PES versus brachytherapy for the treatment of bare-metal ISR, angiographic analyses at 9-month follow-up were available in 184 ISR lesions treated with PES.ResultsIn-stent late loss in entire stented segment of multiple PES (n=50) was 0.45±0.48 mm, whereas that of single PES (n=134) was 0.3±0.47 mm, P=.06. No aneurysm was observed at overlapping PES segments at 9 months. Stent thrombosis up to 9 months was observed in one in each group (single PES, 0.7% vs. multiple PES, 1.8%; P=.47). In a subset of 30 patients, volumetric intravascular ultrasound analysis demonstrated that in-stent net volume obstruction was 12.3±12.4 in single PES (n=20) and 14.9±9.8 in multiple PES (n=10), P=.60. The changes of vessel and lumen at the overlapping PES segment were similar to those of the adjacent 5-mm segments (Δminimum lumen area, mm2: ?1.2±1.0, ?1.1±1.1, ?0.8±0.9, P=.48; Δvessel volume, mm3/mm: ?0.2±1.4, 0.1±1.7, 0.3±1.3, P=.37; proximal, overlap, distal segment, respectively). There was no late incomplete stent apposition at overlapping PES segments.ConclusionsNo in vivo evidence of adverse local vessel response at the site of overlapping PES for the treatment of bare-metal ISR has been demonstrated. 相似文献
104.
Mohammad-Reza Movahed Tony Ngoc Nguyen Kent McAllister Jenchen Yang 《Cardiovascular Revascularization Medicine》2006,7(3):189-191
We present a case of intermittent cessation of blood flow through stent struts during systole, with normal flow during diastole in the previously stented ostial vein graft. After reviewing the initial procedure, we discovered that the operator had difficulty in positioning the stent. After stent deployment, the ostial stent was malpositioned and was protruding more than 50% into the aorta. During systole, the contrast in the stent struts, which are situated in the aorta, was being washed off by systolic blood flow, while in the diastole, the flow of contrast was normal. This is the first case report of this observation with a brief review. 相似文献
105.
Long-term anatomic fate of coronary-artery bypass grafts and functional status of patients five years after operation. 总被引:3,自引:0,他引:3
S F Seides J S Borer K M Kent D R Rosing C L McIntosh S E Epstein 《The New England journal of medicine》1978,298(22):1213-1217
To assess long-term results, coronary and graft angiography was performed 53 to 84 months after operation in 22 of 30 consecutive patients who had undergone coronary-artery bypass grafting before 1973, and who had at least one graft patent at an early (three to nine months) postoperative study. Of the 33 grafts, 31 were patent at late study. All patients had severe symptoms before operation. Of 16 who became asymptomatic early after operation, angina pectoris later redeveloped in 11. Progression of disease in ungrafted vessels accounted for symptomatic deterioration in nine of these 11 patients. We conclude that most grafts patent several months after operation remain so for at least 4 1/2 years, and that although most patients improve symptomatically after operation, symptomatic deterioration is common in the succeeding years and is most often due to progression of disease in ungrafted vessels. 相似文献
106.
Ischemic stroke is a significant health problem affecting over 6 million people in the United States alone. In addition to surgical and thrombolytic therapeutic strategies for stroke, neuroprotective therapies may offer additional benefit. N-acylethanolamines (NAEs) are signaling lipids whose synthesis is upregulated in response to ischemia, suggesting that they may be neuroprotective. To date only three NAEs, arachidonylethanolamide (NAE 20:4), palmitoylethanolamide (NAE 16:0) and oleoylethanolamide (NAE 18:1) have shown to exert neuroprotective effect in animal models for stroke. Here, we describe neuroprotective effects of the hitherto uncharacterized NAEs, lauroylethanolamide (NAE 12:0) and linoleoylethanolamide (NAE 18:2) in a middle cerebral artery occlusion model of stroke. Pretreatment with NAE 18:2 prior to ischemia/reperfusion (I/R) injury resulted in both significantly reduced cortical infarct volume and improved functional outcome as determined using the neurological deficit score. NAE 12:0 improved neurological deficits without a significant reduction lesion size. Our results suggest that NAEs, as a whole, provide neuroprotection during I/R injury and may have therapeutic benefit when used as complementary treatment with other therapies to improve stroke outcome. 相似文献
107.
William D.T. Kent Adarsh Manjunath S. Chris Malaisrie 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2014,41(3):341-343
The frozen elephant trunk procedure is a hybrid, single-staged alternative to conventional surgery for repairing diffuse pathologic conditions of the thoracic aorta. This approach is particularly advantageous in patients who have pathologic conditions of the left side of the chest, because the descending thoracic aorta can be repaired without entering a hostile pleural cavity.We present the case of a 67-year-old man who had undergone repair of acute type A aortic dissection. He presented with aneurysmal dilation of the descending thoracic aorta secondary to chronic dissection, a large acute dissection of the proximal ascending aorta, and a large paraesophageal hernia that made him a poor candidate for conventional, 2-staged open aortic repair. We describe the hybrid frozen elephant trunk technique that we used to repair the aorta, and its broader advantages. 相似文献
108.
Loscalzo ML Goh DL Loeys B Kent KC Spevak PJ Dietz HC 《American journal of medical genetics. Part A》2007,(17):1960-1967
The autosomal dominant inheritance of bicommissural aortic valve (BAV) (Online Mendelian Inheritance in Man #109730) in some families is well-documented; however, the inheritance of BAV with thoracic aortic aneurysm (TAA) is less clear. Whether the aneurysm is secondary to hemodynamic perturbation related to the valve abnormality or a primary manifestation of the disorder remains controversial. Guidelines are needed regarding the follow-up and treatment of these patients and their families. Thirteen families with at least one individual with TAA and BAV (BAV/TAA) were evaluated prospectively by standard echocardiographic methods or clinical history. Affected status was determined by the presence of BAV or TAA or a history of dissection, rupture, or surgical repair. Six of 13 families had at least two family members with both BAV and TAA, often in successive generations. Informatively, all 13 families had at least one family member with TAA in the absence of BAV. Thirty-five percent (39/110) of family members had BAV/TAA or TAA, and the majority of families (11/13) had maximal dilatation above the sinotubular junction (STJ). Vascular dissection or rupture occurred in seven of 13 families and in individuals with structurally normal aortic valves. Two families had non-manifesting, obligate carriers. Three families have members with other left heart outflow tract anomalies. This study confirms autosomal dominant inheritance with incomplete penetrance for BAV/TAA in these families. Furthermore, our data suggest that the component features, BAV and TAA, are independent manifestations of a single gene defect. To avoid the risk of early death, it is essential that all first-degree relatives receive echocardiographic follow-up at regular intervals regardless of the presence or absence of a BAV. This assessment must include imaging of the aortic region above the STJ. 相似文献
109.
Few studies have characterized or compared the pathologic features of bone marrow involvement by extranodal (EMZL), splenic (SMZL), and nodal marginal zone lymphoma (NMZL). We evaluated 45 bone marrow biopsy specimens from 39 patients with marginal zone lymphomas. As previously reported, bone marrow involvement was frequent (100%) in patients with SMZL. We also identified lymphoma involving bone marrow in 11 (44%) of 25 patients with EMZL and 1 of 2 patients with NMZL. The patterns of infiltration were mixed in all groups; however, the extent of involvement was greater in SMZL than in EMZL. In addition, germinal centers were present in bone marrow biopsy specimens involved by lymphoma in 4 patients with SMZL. Intrasinusoidal infiltration was common (10/12 [83%]) and prominent in patients with bone marrow involvement by SMZL, but was not invariably present. Intrasinusoidal infiltration of the bone marrow also was not specific for SMZL since similar infiltrates, although subtle, also were found in patients with other small B-cell lymphoproliferative disorders, including 6 (55%) of 11 patients whose bone marrow samples were infiltrated by EMZL. 相似文献
110.
Emma Sprooten Cota Navin Gupta Emma E.M. Knowles D. Reese McKay Samuel R. Mathias Joanne E. Curran Jack W. Kent Jr Melanie A. Carless Marcio A. Almeida Thomas D. Dyer Harald H.H. Göring Rene L. Olvera Peter Kochunov Peter T. Fox Ravi Duggirala Laura Almasy Vince D. Calhoun John Blangero Jessica A. Turner David C. Glahn 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2015,168(8):678-686