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991.
Overall stent performance should be characterized by geometric luminal gain acquisition, neointimal coverage of the stent struts, and stabilization of the underlying inflammatory neoatheroma. The aim of this study was to compare the performance of zotarolimus-eluting stent (ZES), everolimus-eluting stent (EES) and bare metal stent (BMS) using optical coherence tomography (OCT) and coronary angioscopy. For 36 stented coronary lesions (BMS, 12 lesions; ZES, 11 lesions; EES, 13 lesions) in 27 patients, we calculated neointimal area and uncovered stent strut rate based on OCT findings at 10 months after stent placement. The grades of neointimal coverage and yellow color, both of which were classified from 0 to 3, were also assessed by coronary angioscopy. The plaque area of the ZES lesions was larger than that of the EES lesions (P < 0.05) but smaller than that of the BMS lesions (P < 0.05). The OCT-based uncovered rate of the ZES lesions was less than that of the EES lesions (P < 0.01), but similar to that of the BMS lesions. The stent coverage grade by angioscopy was higher in the ZES lesions than in the EES lesions (P < 0.05), but similar to the BMS lesions. The yellow grade was less in the ZES lesions than in the EES lesions (P < 0.01), but similar to the BMS lesions. ZES might be better than BMS in terms of neointimal thickening, and better than EES in terms of neointimal coverage as well as prevention of neoatheroma formation. ZES may have superior performance compared with EES.  相似文献   
992.
BACKGROUND: Reclining in the right lateral decubitus position in chronic heart failure (CHF) is a self-protective mechanism for normalizing impaired cardiac autonomic nervous activity (CANA). HYPOTHESIS: Candesartan, an angiotensin II receptor blocker, exerts beneficial effects on CANA and postural preferences in patients with CHF. METHODS: We studied 15 patients with CHF due to coronary artery disease. Cardiac autonomic nervous activity was assessed using spectral heart rate variability (HRV) analysis based on 24-h ambulatory electrocardiogram monitoring before and after an 8-week treatment with candesartan. The patients' posture was simultaneously recorded using a specially devised detector, as the right (R) or left (L) lateral decubitus or supine (S) positions, to evaluate postural modulations of CANA. Normalized high-frequency (0.15 to 0.40 Hz) power (nHF) and the low-frequency (0.04 to 0.15 Hz)/high-frequency power ratio (LF/HF) were used as indices of vagal activity and sympathovagal balance, respectively. RESULTS: When HRV was analyzed in each position, CANA was changed in L and S, but not in R, from sympathetic to parasympathetic prevalence by the treatment (R, nHF, 50 +/- 20 vs. 52 +/- 19 nu, p = 0.87; LF/HF, 1.39 +/- 1.11 vs. 1.32 +/- 1.32, p =0.93; L, nHF, 28 +/- 13 vs. 47 +/- 19 nu, p = 0.019; LF/HF, 3.34 +/- 2.48 vs. 1.56 +/- 1.39, p = 0.029; S, nHF, 38 +/- 17 vs. 53 +/- 16 nu, p = 0.0023; LF/HF, 2.43 +/- 2.21 vs. 1.03 +/- 0.59, p = 0.025). The fractions of the time in R and L were decreased and increased, respectively, by the treatment (R, 40 +/- 30 vs. 18 +/- 24%, p = 0.0018; L, 11 +/- 20 vs. 27 +/- 26%, p = 0.025). CONCLUSIONS: In patients with CHF, candesartan treatment improves cardiac autonomic balance, and the preference for the right lateral decubitus position disappears after the treatment.  相似文献   
993.
The mechanisms by which fibroblast growth factor 23 (FGF23) alters inorganic phosphate (Pi) homeostasis is not entirely clear. In the present study, we examined the effect of FGF23 on intestinal sodium-dependent Pi transport in mice. Injection of FGF23(R179Q) markedly reduced serum Pi and 1,25(OH)2D3 levels in normal mice. Those animals show the reduction of intestinal sodium-dependent Pi transport activity and the amount of type IIb sodium-dependent Pi cotransporter (type IIb NaPi) protein in the brush border membrane vesicles. In vitamin D receptor null mice (VDR-/-), FGF23(R179Q) had no effect on intestinal sodium-dependent Pi transport activity and type IIb NaPi protein levels. The present study suggests that FGF23(R179Q) reduces intestinal sodium-dependent Pi transport activity and type IIb NaPi protein levels by a mechanism that is dependent on VDR.  相似文献   
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Although the cellular and molecular mechanisms governing angiogenesis are only beginning to be understood, signaling through endothelial-restricted receptors, particularly receptor tyrosine kinases, has been shown to play a pivotal role in these events. Recent reports show that EphB receptor tyrosine kinases and their transmembrane-type ephrin-B2 ligands play essential roles in the embryonic vasculature. These studies suggest that cell-to-cell repellent effects due to bidirectional EphB/ephrin-B2 signaling may be crucial for vascular development, similar to the mechanism described for neuronal development. To test this hypothesis, we disrupted the precise expression pattern of EphB/ephrin-B2 in vivo by generating transgenic (CAGp-ephrin-B2 Tg) mice that express ephrin-B2 under the control of a ubiquitous and constitutive promoter, CMV enhancer-beta-actin promoter-beta-globin splicing acceptor (CAG). These mice displayed an abnormal segmental arrangement of intersomitic vessels, while such anomalies were not observed in Tie-2p-ephrin-B2 Tg mice in which ephrin-B2 was overexpressed in only vascular endothelial cells (ECs). This finding suggests that non-ECs expressing ephrin-B2 alter the migration of ECs expressing EphB receptors into the intersomitic region where ephrin-B2 expression is normally absent. CAGp-ephrin-B2 Tg mice show sudden death at neonatal stages from aortic dissecting aneurysms due to defective recruitment of vascular smooth muscle cells to the ascending aorta. EphB/ephrin-B2 signaling between endothelial cells and surrounding mesenchymal cells plays an essential role in vasculogenesis, angiogenesis, and vessel maturation.  相似文献   
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We evaluated the incidence and outcome of lung involvement in 35 patients with autoimmune pancreatitis (AIP). Our results indicate that lung involvement is commonly observed in AIP (40%). In addition, corticosteroid treatment improved the lung lesions and appeared to reduce the probability of relapse compared with pancreatic lesions (0% vs 36%). This is the first report to assess the long‐term outcome of lung involvement in AIP (52 ± 33 months).  相似文献   
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Journal of Interventional Cardiac Electrophysiology - Concealed sinus node dysfunction (SND) may become manifest after restoration of sinus rhythm by ablation in patients with persistent atrial...  相似文献   
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