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561.
Aim The aim of this study was to investigate the relationships between bone mineral density (BMD) vs insulin resistance and metabolic risk factors in obese adolescents with nonalcoholic fatty liver disease (NAFLD). Patients and methods Eighty‐two obese adolescents [45 girls and 37 boys, mean age: 12·3 ± 1·7 years, mean body mass index‐standard deviation score (BMI‐SDS): 1·9 ± 0·2] and 30 control subjects (15 girls and 15 boys, mean age: 12·3 ± 1·45 years, mean BMI‐SDS: 0·5 ± 0·7) were enrolled the study. The obese subjects were divided into two groups based on the presence or absence of liver steatosis with high transaminases (NAFLD group and non‐NAFLD group). Insulin resistance was evaluated by homeostasis model assessment (HOMA‐IR) from fasting samples. BMD was determined by dual‐energy X‐ray absorptiometry. Results Fasting insulin levels in the NAFLD group were significantly higher than in the non‐NAFLD obese (32·3 ± 24·0 vs 11·02 ± 2·95 mU/l, P < 0·001) and control groups (8·4 ± 2·4 mU/l, P< 0·001). The NAFLD group had higher values of HOMA‐IR than the non‐NAFLD obese (7·3 ± 0·1 vs 2·3 ± 0·7, P < 0·001) and control groups (1·8 ± 0·5, P < 0·001). BMD‐SDS measurements were lower in the NAFLD group than in the non‐NAFLD (0·56 ± 0·3 vs 1·02 ± 0·9, P < 0·001) and control groups (0·56 ± 0·3 vs 1·37 ± 1·04, P < 0·001). BMD‐SDS was positively correlated with BMI‐SDS (r = 0·530, P = 0·004) and negatively correlated with HOMA‐IR (r = ?0·628, P = 0·017) in the NAFLD obese group. Conclusion This study reports the association between BMD‐SDS and insulin resistance in obese adolescents both with and without NAFLD, although the NAFLD group had a lower BMD‐SDS than the non‐NAFLD group. We suggest that NAFLD has a detrimental effect on bone health in adolescents, and it is correlated with increased insulin resistance.  相似文献   
562.
Background: Carotid intima‐media thickness (CIMT) is a potential indicator of subclinical atherosclerosis in patients with metabolic syndrome (MetS). Epicardial fat thickness (EFT) is suggested as a new cardiometabolic risk factor. We investigated the association between EFT and CIMT in patients with MetS. Methods: Forty patients with MetS were compared with 40 age‐ and sex‐matched subjects without MetS in terms of echocardiographic EFT, CIMT, anthropometric measurements, and metabolic profile in this cross‐sectional study. Results: The waist circumference, total and LDL‐cholesterol, fasting glucose, triglycerides, systolics and diastolic blood pressure levels, hs‐CRP, and homeostasis model assessment index for insulin resistance (HOMA‐IR) were significantly increased in patients with MetS. The EFT and CIMT were also increased significantly in patients with MetS compared to controls (7.2 ± 2 mm vs. 5.7 ± 1.9 mm; P = 0.001, 0.74 ± 0.1 mm vs. 0.59 ± 0.1 mm; P < 0.01, respectively). Echocardiographic EFT was the only independent predictor of CIMT in the multivariate analysis (standardized β coefficient = 0.74, P < 0.001). Conclusion: EFT is associated with increased CIMT in patients with MetS. (Echocardiography 2011;28:853‐858)  相似文献   
563.
Objectives: Primary hyperparathyroidism (PHP) is associated with a variety of cardiovascular disturbances such as left ventricular (LV) hypertrophy, diastolic cardiac dysfunction, and hypertension. LV asynchrony is defined as the loss of the simultaneous peak contraction of corresponding cardiac segments. The objective of this study was to assess systolic asynchrony in patients with overt hyperparthyroidism. Methods: Asynchrony was evaluated in 22 patients with PHP and 24 controls. All the patients and controls were subjected to a tissue synchronization imaging (TSI). The time to regional peak systolic tissue velocity (Ts) in LV by the six‐basal‐six‐midsegmental model was measured on ejection phase TSI images and four TSI parameters of systolic asynchrony were computed. Results: All TSI parameters of LV asynchrony increased in patients with PHP patients compared to the controls: the standard deviation (SD) of the 12 LV segments Ts (37.3 ± 20.6 vs. 21.5 ± 11.1, P = 0.01); the maximal difference in Ts between any 2 of the 12 LV segments (111.2 ± 59.8 vs. 70.2 ± 32.1, P = 0.01); the SD of the 6 basal LV segments (42.9 ± 36.4 vs. 18.5 ± 13, P = 0.003); and the maximal difference in Ts between any 2 of the 6 basal LV segments (89.6 ± 50.5 vs. 48 ± 31.1, P = 0.003). Conclusion: Patients with PHP show an evidence of LV asynchrony by TSI. Asynchrony may contribute to the harmful cardiovascular effects of PHP. (Echocardiography 2011;28:955‐960)  相似文献   
564.
[Purpose] Sclerostin is mechanosensitive protein that is produced exclusively by osteocytes. It was reported that the plasma sclerostin level increases in the 10th minute after the application of Whole-Body Vibration. The aim of this study was to determine whether single extremity-vibration induces any change in the serum sclerostin level. [Subjects and Methods] Eight healthy young-adult volunteers were recruited for this pilot study. The participants sat on a chair with their left hip and knee joints flexed at 90 degrees. The lower leg was exposed to vibration: 40 Hz, 4 mm, 60 s. Blood samples were collected before and after the vibration. The serum sclerostin levels were blindly measured in dual-controlled blood samples. [Results] The serum sclerostin level before vibration was 328.2±589.9 pg/ml, and it showed no significant change after vibration. [Conclusion] Unlike Whole-Body Vibration, Single-Extremity Vibration did not affect the serum sclerostin level significantly. This finding can be explained by the limited bone volume exposed to vibration. Bone volume exposed to vibration is less during Single-Extremity Vibration than during Whole-Body Vibration.Key words: Sclerostin, Whole-Body Vibration, Bone  相似文献   
565.
OBJECTIVE: Carotid artery intima-media thickness (IMT) is now widely used as a surrogate marker for atherosclerotic disease. Carotid IMT measured by ultrasound has been shown to be correlated with coronary artery disease as defined by angiography. However, the relation between carotid IMT and isolated coronary artery ectasia (CAE) has not been investigated. The aim of our study was to assess this relation. METHODS: Twenty-five patients with isolated CAE without stenosis and 25 control subjects with angiographically normal coronary arteries were included in this study. These were examined by B-mode ultrasound to measure the IMT at the far wall of the common carotid artery. RESULTS: Patients with isolated CAE had significantly higher carotid IMT compared to control subjects with angiographically normal coronary arteries (0.95+/-0.12 versus 0.71+/-0.10mm respectively, p<0.0001). In addition, we detected a significant positive correlation between the presence of CAE and carotid IMT (r=0.748, p<0.001). CONCLUSION: We have shown for the first time an association between increased carotid IMT and isolated CAE, suggesting that atherosclerosis may be involved in the pathogenesis of isolated CAE in the adult population.  相似文献   
566.
OBJECTIVE: We performed this prospective study on patients with signs and symptoms of chronic venous disease to emphasize short saphenous vein (SSV) insufficiency, which is not routinely evaluated with Doppler ultrasonography in every center. METHODS: One hundred seventy-eight patients with signs and symptoms of chronic venous disease were included in the study. We used the CEAP (clinical, etiologic, anatomic, and pathophysiologic data) classification in evaluation of the limbs with isolated and nonisolated SSV incompetence. Patients were classified according to age, occupation, body mass index, and associated chronic illness. A chi(2) test and a t test were used in the statistical analysis. RESULTS: Reflux was observed in 190 (53%) of 356 limbs. In 11 limbs, isolated SSV reflux was observed. These 11 limbs were classified as CEAP grade 2 (3 limbs), CEAP grade 3 (3 limbs), and CEAP grade 4 (5 limbs). Short saphenous vein reflux was observed in 21 (5.9%) of 356 limbs. Mean SSV diameters were 3.89 mm (range, 1-11 mm) on the right and 4.03 mm (1.3-10 mm) on the left. CONCLUSIONS: No statistical significance was found between age, sex, body mass index, occupation, and associated chronic disease and deep or superficial venous system incompetence. A statistically significant difference was found between the SSV diameter of the limbs and associated venous incompetence.  相似文献   
567.
BackgroundAtrial electromechanical delay (EMD) parameters predict the development of atrial fibrillation. We investigated the effect of telmisartan treatment on atrial EMD parameters in patients with newly diagnosed essential hypertension.MethodsThirty-six patients with essential hypertension were treated with telmisartan (80 mg/day) for 6 months. Baseline electrocardiographic P-wave measurements and echocardiographic atrial EMD parameters were compared with the 6-month follow-up.ResultsPmax and Pd were significantly decreased (108.4 ± 6.1 vs 93.9 ± 6.2 milliseconds, 33.4 ± 8.6 vs 19.5 ± 7.0 milliseconds, respectively, P = .0001 for each) after 6-month telmisartan therapy. The atrial EMD parameters were decreased from baseline (mitral EMD, 68.9 ± 4.9 vs 53.8 ± 4.9 milliseconds; septum EMD, 51.6 ± 7.1 vs 42.6 ± 7. milliseconds1; tricuspid EMD, 48 ± 6.9 vs 39 ± 6.9 milliseconds; interatrial EMD, 20.9 ± 5.5 vs 14.8 ± 5.7 milliseconds; P = .0001 for each parameter). The reduction of interatrial EMD was correlated with the reduction in systolic BP nighttime and the increase in mitral E wave velocity/mitral A wave velocity ratio.ConclusionTelmisartan decreased the atrial EMD parameters in patients with newly diagnosed essential hypertension.  相似文献   
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