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Biomarkers of endothelial dysfunction and risk of type 2 diabetes mellitus   总被引:31,自引:0,他引:31  
Meigs JB  Hu FB  Rifai N  Manson JE 《JAMA》2004,291(16):1978-1986
Context  Endothelial dysfunction occurs in diagnosed type 2 diabetes mellitus but may also precede development of diabetes. Objective  To determine whether elevated plasma levels of biomarkers reflecting endothelial dysfunction (E-selectin; intercellular adhesion molecule 1 [ICAM-1]; and vascular cell adhesion molecule 1 [VCAM-1]) predict development of type 2 diabetes in initially nondiabetic women. Design and Setting  Prospective, nested case-control study within the Nurses' Health Study, an ongoing US study initiated in 1976. Participants  Of 121 700 women initially enrolled, 32 826 provided blood samples in 1989-1990; of those free of diabetes, cardiovascular disease, or cancer at baseline, 737 developed incident diabetes by 2000. Controls (n = 785) were selected according to matched age, fasting status, and race. Main Outcome Measure  Risk of confirmed clinically diagnosed type 2 diabetes by baseline levels of E-selectin, ICAM-1, and VCAM-1. Results  Baseline median levels of the biomarkers were significantly higher among cases than among controls (E-selectin, 61.2 vs 45.4 ng/mL; ICAM-1, 264.9 vs 247.0 ng/mL; VCAM-1, 545.4 vs 526.0 ng/mL [all P values .004]). Elevated E-selectin and ICAM-1 levels predicted incident diabetes in logistic regression models conditioned on matching criteria and adjusted for body mass index (BMI), family history of diabetes, smoking, diet score, alcohol intake, activity index, and postmenopausal hormone use. The adjusted relative risks for incident diabetes in the top quintile vs the bottom quintiles were 5.43 for E-selectin (95% confidence interval [CI], 3.47-8.50), 3.56 for ICAM-1 (95% CI, 2.28-5.58), and 1.12 for VCAM-1 (95% CI, 0.76-1.66). Adjustment for waist circumference instead of BMI or further adjustment for baseline levels of C-reactive protein, fasting insulin, and hemoglobin A1c or exclusion of cases diagnosed during the first 4 years of follow-up did not alter these associations. Conclusion  Endothelial dysfunction predicts type 2 diabetes in women independent of other known risk factors, including obesity and subclinical inflammation.   相似文献   
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<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],  相似文献   
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Patients with hemophilia suffer from low bone mineral density (BMD) due to several risk factors including arthropathy and resulting immobility. Recent studies have shown variable frequency of low BMD in this group of patients. This study attempts to assess the prevalence of low BMD (osteoporosis and osteopenia) and the associated risk factors in a group of Iranian hemophilia patients. Patients with moderate or severe hemophilia underwent BMD measurement by dual energy X-ray absorptiometry. The results were correlated with other variables including physical activity, calcium intake and demographic data. Forty two patients with the mean age of 31 years (range 18–72) completed the study. The prevalence of osteoporosis in the spine and the left femoral neck was 23.8 and 14.6 %, respectively, and osteopenia in the spine and femoral neck was seen in 45.2 and 31.7 % of the patients, respectively based on the WHO T-score criteria. We found only cigarette smoking to be significantly related to low BMD (P < 0.001). There were two cases of pathologic fracture at femoral neck and forearm (4.8 %). Low BMD is very common in patients with hemophilia. Appropriate assessment of BMD and control of predisposing factors such as prophylactic factor replacement (to prevent hemarthrosis) and cessation of cigarette smoking are warranted.  相似文献   
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Boiling histotripsy is a non-invasive, cavitation-based ultrasonic technique which uses a number of millisecond pulses to mechanically fractionate tissue. Though a number of studies have demonstrated the efficacy of boiling histotripsy for fractionation of solid tumours, treatment monitoring by cavitation measurement is not well studied because of the limited understanding of the dynamics of bubbles induced by boiling histotripsy. The main objectives of this work are to (a) extract qualitative and quantitative features of bubbles excited by shockwaves and (b) distinguish between the different types of cavitation activity for either a thermally or a mechanically induced lesion in the liver. A numerical bubble model based on the Gilmore equation accounting for heat and mass transfer (gas and water vapour) was developed to investigate the dynamics of a single bubble in tissue exposed to different High Intensity Focused Ultrasound fields as a function of temperature variation in the fluid. Furthermore, ex vivo liver experiments were performed with a passive cavitation detection system to obtain acoustic emissions. The numerical simulations showed that the asymmetry in a shockwave and water vapour transport are the key parameters which lead the bubble to undergo rectified growth at a boiling temperature of 100°C. The onset of rectified radial bubble motion manifested itself as (a) an increase in the radiated pressure and (b) the sudden appearance of higher order multiple harmonics in the corresponding spectrogram. Examining the frequency spectra produced by the thermal ablation and the boiling histotripsy exposures, it was observed that higher order multiple harmonics as well as higher levels of broadband emissions occurred during the boiling histotripsy insonation. These unique features in the emitted acoustic signals were consistent with the experimental measurements. These features can, therefore, be used to monitor (a) the different types of acoustic cavitation activity for either a thermal ablation or a mechanical fractionation process and (b) the onset of the formation of a boiling bubble at the focus in the course of HIFU exposure.  相似文献   
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Background

Although used as criterion for early drain removal, postoperative day (POD) 1 drain fluid amylase (DFA) ≤ 5000 U/L has low negative predictive value for clinically relevant postoperative pancreatic fistula (CR-POPF). It was hypothesized that POD3 DFA ≤ 350 could provide further information to guide early drain removal.

Methods

Data from a pancreas surgery consortium database for pancreatoduodenectomy and distal pancreatectomy patients were analyzed retrospectively. Those patients without drains or POD 1 and 3 DFA data were excluded. Patients with POD1 DFA ≤ 5000 were divided into groups based on POD3 DFA: Group A (≤350) and Group B (>350). Operative characteristics and 60-day outcomes were compared using chi-square test.

Results

Among 687 patients in the database, all data were available for 380. Fifty-five (14.5%) had a POD1 DFA > 5000. Among 325 with POD1 DFA ≤ 5000, 254 (78.2%) were in Group A and 71 (21.8%) in Group B. Complications (35 (49.3%) vs 87 (34.4%); p = 0.021) and CR-POPF (13 (18.3%) vs 10 (3.9%); p < 0.001) were more frequent in Group B.

Conclusions

In patients with POD1 DFA ≤ 5000, POD3 DFA ≤ 350 may be a practical test to guide safe early drain removal. Further prospective testing may be useful.  相似文献   
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