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Background and aims

Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.

Methods and results

In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.

Conclusion

SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE.  相似文献   
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OBJECTIVES: The aim of this study is to evaluate the effect of ZnSO(4) addition to a conventional glass ionomer and a resin-modified glass ionomer on solubility, flexural strength, zinc and fluoride (F) release, and Streptococcus mutans growth inhibition. METHODS: 5 or 10% ZnSO(4) was added to Vitremer and Ketac-Fil powders. Solubility test was performed based on ISO 7489. Flexural strength was determined by 3-point bending test based on ISO 4049. Zn release/uptake was determined by atomic emission spectrometry; F release/uptake was measured using a F-specific electrode. Both release measurements were performed for 15 d before and 15 d after recharging. Antibacterial test was conducted according to agar plate methods against S. mutans, by measuring the inhibition halos in 1-h and 15-d specimens. Data were analyzed by ANOVA. RESULTS: Solubility increased with higher ZnSO(4) content, but remained below the ISO 7489 limit. Flexural strength was not affected by ZnSO(4) addition, and Vitremer performed better than Ketac-Fil. The control materials released no zinc. Vitremer with 10% ZnSO(4) released the highest amount of zinc. Fluoride release was similar for Ketac-Fil and Vitremer. In both cases, the highest amounts were released in the first 24 h. The growth inhibition halo of S. mutans was similar for both materials with highest content of ZnSO(4) and occurred only with 1-h specimens. SIGNIFICANCE: Zinc addition decreased microorganisms growth and improved fluoride release, without significantly affecting the materials' flexural strength and solubility.  相似文献   
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The aim of the study was to evaluate differences in the relationship between peripheral diabetic neuropathy and microvascular reactivity in type 1 and type 2 diabetic patients. Twenty-eight type 1 and 37 type 2 diabetic patients were included in the study. Control groups consisted of 18 and 25, age and body mass index matched healthy persons. The presence of peripheral neuropathy was estimated by vibration perception threshold higher than 20 V evaluated by biothesiometry. Microvascular reactivity was examined by laser doppler fluxmetry using postocclusive reactive hyperemia and thermal hyperemia. The following variables of vascular reactivity were examined: peak flow after occlusion as a difference between maximal and basal perfusion (PORH (max)), mean velocity increase during postocclusive hyperemia (PORH (max)/t (1)), peak flow during thermal hyperemia (TH (max)) and the mean velocity increase in the perfusion during thermal hyperemia (TH (max)/t (2)). These parameters are expressed in perfusion units (PU) or in perfusion units per second (PU . s (-1)). The microvascular reactivity in type 1 diabetic patients without evidence of peripheral neuropathy was comparable with that in healthy persons and it was significantly higher than in type 1 diabetic patients with peripheral neuropathy in all tested parameters (PORH (max): 64 [40; 81] PU vs. 24 [17; 40] PU, p < 0.001, PORH (max)/t (1): 5.41 [2.69; 8.18] PU/s vs. 1.21 [0.69; 2.5] PU/s, p < 0.001, TH (max): 105 [77; 156] PU vs. 56 [46; 85] PU, p < 0.001 and TH (max)/t (2): 2.48 [1.67; 3.33] PU/s vs. 0.87 [0.73; 1.06] PU/s, p < 0.001). On the contrary, no difference in the microvascular reactivity parameters was found between type 2 diabetic patients with and without neuropathy (PORH (max): 48 [30; 60] PU vs. 49 [36; 57] PU, NS, PORH (max)/t (1): 3.46 [2.15; 5.19] PU/s vs. 3.29 [2.45; 4.8] PU/s, NS, TH (max): 95 [78; 156] PU vs. 97 [73; 127] PU, NS and TH (max)/t (2): 1.45 [0.95; 2.84] PU/s vs. 1.37 [1.12; 1.95] PU/s, NS). In both these groups microvascular reactivity was comparable with that estimated in the age and BMI matched healthy persons. An inverse relationship was observed between microvascular reactivity and vibratory perception threshold in type 1 diabetic patients, but it was not true in type 2 diabetic patients. We suppose that the pathogenesis of neuropathy and impaired microvascular reactivity may be differently influenced by metabolic factors in type 1 and type 2 diabetic patients.  相似文献   
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