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81.
BACKGROUND: There is great need for simple anthropometric measures that predict risk. The authors explored the relationship between body composition measures and features of the metabolic syndrome (MtS) in women aged between 20 and 50 years with class I obesity. METHODS:This is a cross-sectional study of 49 obese (BMI 30-35) women recruited into a weight management randomized trial. An analysis was conducted of the baseline weight, anthropometric measures, skin-fold thickness, bioelectrical impedance, whole body dual-energy x-ray absorptiometry (DEXA), and their relationships with the features of the MtS. RESULTS: All women but one (n=48) had a population risk waist circumference of >88 cm. 16 of the 49 (33%) fulfilled the criteria of the metabolic syndrome. Simple anthropometric measures provided the strongest correlations with the presence of the MtS. Cut-off values were selected using receiver operator characteristics. Waist circumference of >100 cm and hip circumference <115cm was associated with odds ratios of 5.2 (95% CI, 1.4-20) and 12.3 (95% CI, 3.0-51) respectively for the MtS. Regional DEXA analysis showed that lower leg fat mass rather than fat-free mass was associated with the MtS. The dyslipidemia of the MtS was associated with a lower leg fat mass, while higher HbAlc levels and HOMA, an indirect measure of insulin resistance, were seen with increased trunk fat. Percentage fat as measured by skin-fold thickness and bioelectrical impedance were not related to any features. Women with the metabolic syndrome were found to have lower bone mineral content as measured by DEXA. CONCLUSION: Weight distribution is highly predictive of metabolic risk. Smaller hip and larger waist circumference provided independent effect. BMI adjusted anthropometric measures may be of value. 相似文献
82.
Cheryl A. Krause‐Parello Erika Friedmann Candy Wilson Jennifer J. Hatzfeld John Kolassa Alisha Hackney Kristie A. Morales 《Stress and health》2019,35(4):480-490
Animal‐assisted interventions (AAIs) have been found to decrease stress in some settings, but it is not known if AAI is feasible in an aeromedical staging facility or effective in reducing stress following aeromedical evacuation (AE) of military personnel. An experimental design was used to evaluate the efficacy of AAI at reducing stress in AE military patients (N = 120). Patients participated in a 20‐min AAI (n = 60) or 20‐min informational session about assistance dogs as an attention‐control group (n = 60). Demographics, post‐traumatic stress symptom severity (PTSSS), and stress biomarkers (cortisol, alpha‐amylase, and immunoglobulin A) were collected regular intervals. AAI was found feasible and efficacious at reducing stress. Cortisol decreased significantly (p < .05) in the AAI group compared with the attention‐control group. PTSSS moderated the immunoglobulin A responses to AAI as demonstrated by the interaction of PTSD Checklist–Military Version score, group, and time, F(1, 111.23) = 4.15 p = .044; effect size: d = 0.31. This research supports AAI as a stress‐reducing modality in AE patients, particularly those who report higher PTSSS. Implications for future research are discussed. 相似文献
83.
PURPOSE: We used the rabbit model of obesity and exercise training to determine effects of exercise training during the development of obesity on resting blood pressure and heart rate, ventricular hypertrophy, blood volume, and hormonal profile. METHODS: Female New Zealand white rabbits were assigned to one of four groups: lean sedentary (L-S, N = 17), lean exercise-trained (L-EX, N = 16), obese sedentary (O-S, N = 18), and obese exercise-trained (O-EX, N = 15). Lean rabbits were fed a maintenance diet whereas obese rabbits were fed an ad libitum high fat (10% added fat) diet. Simultaneously, exercise-trained animals underwent a progressive treadmill exercise training protocol for 12 wk. After 12 wk of diet and exercise regimens, resting blood pressure and heart rate were measured from a central ear artery catheter. Ventricular hypertrophy was evaluated using wet ventricular weights. Blood volume was measured using the Evans blue dye procedure; hormonal profile was evaluated from arterial plasma/serum samples. RESULTS: After 12 wk, O-S and O-EX had similar body weights and similar percentage increases in body weight. Despite similar body weights, O-EX had an approximate 6-mm Hg lower mean blood pressure compared with the elevated pressure seen in O-S (P < or = 0.05). Obese rabbits had greater resting heart rate, plasma cholesterol and triglycerides, and plasma renin activity compared with lean rabbits, and these values were unaffected by exercise training. Plasma and blood volumes, as well as plasma insulin, cortisol, and aldosterone were unaffected by exercise training. CONCLUSION: These data suggest that exercise training, in the absence of differences in body weight, may be useful in the reduction of obesity-induced hypertension but that other therapies may be needed in order to control other cardiovascular risk factors. 相似文献
84.
Daniel A Herzka Peter Kellman Anthony H Aletras Michael A Guttman Elliot R McVeigh 《Magnetic resonance in medicine》2002,47(4):655-664
Refocused steady-state free precession (SSFP), or fast imaging with steady precession (FISP or TrueFISP), has recently proven valuable for cardiac imaging because of its high signal-to-noise ratio (SNR) and excellent blood-myocardium contrast. In this study, various implementations of multiecho SSFP or EPI-SSFP for imaging in the heart are presented. EPI-SSFP has higher scan-time efficiency than single-echo SSFP, as two or more phase-encode lines are acquired per repetition time (TR) at the cost of a modest increase in TR. To minimize TR, a noninterleaved phase-encode order in conjunction with a phased-array ghost elimination (PAGE) technique was employed, removing the need for echo time shifting (ETS). The multishot implementation of EPI-SSFP was used to decrease the breath-hold duration for cine acquisitions or to increase the temporal or spatial resolution for a fixed breath-hold duration. The greatest gain in efficiency was obtained with the use of a three-echo acquisition. Image quality for cardiac cine applications using multishot EPI-SSFP was comparable to that of single-echo SSFP in terms of blood-myocardium contrast and contrast-to-noise ratio (CNR). The PAGE method considerably reduced flow artifacts due to both the inherent ghost suppression and the concomitant reduction in phase-encode blip size. The increased TR of multishot EPI-SSFP led to a reduced specific absorption rate (SAR) for a fixed RF flip angle, and allowed the use of a larger flip angle without increasing the SAR above the FDA-approved limits. 相似文献
85.
Michael P. Recht Josef Kramer Cheryl A. Petersilge Joseph Yu Mini Pathria Debra Trudell David J. Sartoris Donald Resnick 《Journal of magnetic resonance imaging : JMRI》1994,4(2):173-177
Although magnetic resonance (MR) images of the glenohumeral joint frequently demonstrate intraarticular fluid, no specific criteria have, to the authors' knowledge, been published that allow accurate assessment of the amount of fluid present. Also, despite the increasing use of MR arthrography of the shoulder, the optimal amount of intra-articular fluid that should be used with this technique has not been determined. The authors progressively distended the glenohumeral joint in six cadaveric shoulder specimens with a dilute gadopentetate dimeglumine solution and obtained MR images after injection of 2, 5, 10, 15, and 20 mL of the solution. The pattern of fluid distribution was evaluated, and these results were then used to estimate the amount of fluid that was present in the glenohumeral joint on MR images of 20 shoulders obtained in 12 asymptomatic volunteers. In 14 of these shoulders, intraarticular fluid was present; however, in none was more than 2 mL evident. Results of the cadaveric study also indicated that 15 mL of intraarticular fluid appears to be the optimal amount for MR arthrography. 相似文献
86.
Wong LL Hernandez B Kwee S Albright CL Okimoto G Tsai N 《American journal of surgery》2012,203(6):726-732
BackgroundHawaii has the highest incidence of hepatocellular cancer (HCC) in the United States and the largest proportion of Asians and Pacific Islanders. HCC studies generally combine these groups into 1 ethnicity, and we sought to examine differences between Asian and Pacific Islander subpopulations.MethodsDemographic, clinical, and treatment data for 617 patients with HCC (420 Asians, 114 whites, and 83 Pacific Islanders) were reviewed. Main outcome measures included HCC screening and liver transplantation.ResultsAsian and Pacific Islander subgroups had significantly more immigrants, and age was different between groups. Compared with whites, Pacific Islanders and Filipinos had less HCC screening and liver transplantation procedures, fewer met Milan criteria, and a smaller proportion of those with Milan criteria actually underwent transplantation.ConclusionsThere were significant differences in risk factors, clinical presentation, treatment, and access to care among Asian, Pacific Islander, and white patients with HCC. Future HCC studies may benefit from differentiating subgroups within Asian and Pacific Islander populations to better focus these efforts. 相似文献
87.
88.
Nguyen DH Truong PT Walter CV Hayashi E Christie JL Alexander C 《Annals of surgical oncology》2012,19(9):3028-3034
Purpose
The prognosis of patients with breast cancer presenting with distant metastasis can vary depending on disease extent. This study evaluates a definition of limited M1 disease in association with survival in a cohort of women presenting with metastatic breast cancer.Methods
The study cohort comprised 692 women referred to the BC Cancer Agency between 1996 and 2005 with M1 breast cancer at presentation. Limited M1 disease was defined as <5 metastatic lesions confined to one anatomic subsite. Extensive M1 disease was defined as ??5 lesions or disease in more than one subsite. Clinicopathologic and treatment characteristics and overall survival (OS) were compared between subjects with limited (n?=?233) versus extensive (n?=?459) M1 disease. Multivariable analysis was performed by Cox regression modeling.Results
Median follow-up time was 1.9?years. Five-year Kaplan-Meier OS was significantly higher in patients with limited compared to extensive M1 disease (29.7 vs. 13.1?%, p?0.001). In the multivariable Cox regression analysis, limited M1 disease was significantly associated with OS (hazard ratio 0.51, 95?% confidence interval 0.40?C0.66, p?0.001). The only patient subsets with limited M1 disease with poor 5-year OS <15?% were patients with Eastern Cooperative Oncology Group performance status of ??2 or estrogen receptor-negative status.Conclusions
Limited M1 disease, defined as <5 metastatic lesions confined to one anatomic subsite, is a relevant favorable prognostic factor in patients with stage IV breast cancer. This definition may be used in conjunction with other clinicopathologic factors to select patients for more aggressive systemic and locoregional treatments. 相似文献89.
Transforming growth factor-beta regulation of the insulin-like growth factor binding protein-4 protease system in cultured human osteoblasts. 总被引:5,自引:0,他引:5
Christopher O Ortiz Bing-Kun Chen Laurie K Bale Michael T Overgaard Claus Oxvig Cheryl A Conover 《Journal of bone and mineral research》2003,18(6):1066-1072
IGFBP-4 is an inhibitor of IGF-I in bone. We show that TGF-beta regulates IGFBP-4 and enhances IGF-I-stimulated growth of cultured human bone cells through increased expression of an IGFBP-4 protease, PAPP-A. This effect of TGF-beta on IGF-I bioavailability may promote local bone formation. Insulin-like growth factor binding protein (IGFBP-4) proteolysis is implicated in the regulation of local insulin-like growth factor (IGF)-I bioavailability during bone remodeling. The IGFBP-4 protease secreted by normal adult human osteoblastic (hOB) cells in culture is a novel metalloproteinase, pregnancy-associated plasma protein-A (PAPP-A). We have recently identified an inhibitor of PAPP-A, the precursor form of major basic protein (proMBP). Very little is known about the molecular regulation of this IGFBP-4 protease system. In the present study, we determined the effect of transforming growth factor (TGF)-beta and IGF-II, the two most abundant growth factors in human bone, on PAPP-A and proMBP expression in primary cultures of hOB cells. Treatment with TGF-beta resulted in time- and dose-dependent increases in PAPP-A mRNA expression, with a maximal 12-fold increase after 24 h of stimulation with 10 ng/ml TGF-beta. Increased PAPP-A levels in hOB cell-conditioned medium paralleled PAPP-A gene expression. In addition, TGF-beta completely suppressed proMBP expression. Treatment of hOB cells with IGF-II had no effect on PAPP-A or proMBP gene expression. However, IGFBP-4 proteolysis in cell-free assay was dependent on IGF-II, and there was increased IGF-II-dependent IGFBP-4 protease activity in conditioned medium from hOB cells that were treated with TGF-beta. IGF-I stimulation of hOB cell proliferation was markedly enhanced by pretreatment with TGF-beta and [Leu27]IGF-II, and this enhancement was prevented with protease-resistant IGFBP-4. In summary, TGF-beta regulates IGFBP-4 proteolysis in hOB cells through increased expression of the protease, PAPP-A, and decreased expression of the inhibitor, proMBP. However, functional activation of the IGFBP-4 protease system is dependent on IGF-II, which acts at a post-translational level. These data support a model whereby local TGF-beta and IGF-II in the bone microenvironment coordinately amplify IGF-I bioavailability through controlled IGFBP-4 proteolysis, which may be a means to promote bone formation. 相似文献
90.
PURPOSE: Broadened applications of imaging modalities have increased the incidental detection of renal cell carcinoma (RCC) over the past decade. Previous small series have suggested a prognostic benefit for incidental presentation. This study utilizes a large contemporary patient cohort to examine patterns of RCC presentation and their clinical implications. MATERIALS AND METHODS: Retrospective analysis was performed on 721 patients (260 women, 461 men) who underwent 750 nephrectomies for treatment of RCC between 7/1/89 and 12/31/97; 29 patients required two operations for bilateral RCC. Median age and follow-up were 63 years and 41 months, respectively. Indicators of symptomatic presentation included flank pain, flank mass, hematuria, varicocele, constitutional symptoms, paraneoplastic syndromes, and bone pain related to metastatic disease. Mode of presentation was compared with clinicopathologic parameters using Chi-square and t-test analyses. Survival analysis was performed using Kaplan-Meier estimates (log-rank test) and Cox regression modeling. RESULTS: Incidental and symptomatic presentation occurred in 57% and 42% of cases, respectively. When compared to incidental cases, symptomatic presentation was predominantly detected in younger patients (mean age, 59 years; P < .001), in males (P < .04), and in tumors with conventional (clear cell) histology (P < .001), larger size (mean, 8 cm; P < .001), and non-organ confined pathology (P < .001). In univariate analysis, symptomatic cases had a more adverse disease-free (P < .0001) and disease-specific (P < .0001) survival. In multivariate analysis, mode of presentation was an independent predictor of disease-free (P < 0.0001) and disease-specific survival (P < 0.005). CONCLUSIONS: Symptomatic presentation correlates with an aggressive histology and advanced disease. Incidental tumors may be frequently detected in female and elderly patients, as these groups traditionally seek general medical care more regularly. Mode of presentation can independently predict an adverse patient outcome and should be included in RCC-specific modeling systems. 相似文献