553 research outputs found
Preventive effect of statin pretreatment on contrast-induced acute kidney injury in patients undergoing coronary angioplasty: Propensity score analysis from a multicenter registry
BackgroundThe prophylactic benefit of statins in reducing the incidence of contrast-induced acute kidney injury (CI-AKI) has been investigated in several studies with conflicting results. We sought to investigate whether statin pretreatment prevents CI-AKI in coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI).MethodsA total of 2198 CAD patients who underwent PCI, except for those undergoing dialysis or who died within 7 days after angioplasty, were analyzed from the ICAS (Ibaraki Cardiovascular Assessment Study) multicenter registry. Analyzed subjects were divided into 2 groups according to statin pretreatment: statin pretreatment (n = 839) and non-statin pretreatment (n = 1359). Selection bias of statin pretreatment was adjusted by propensity score-matching method: pretreatment statin (n = 565) and non-statin pretreatment (n = 565). CI-AKI was defined as an increase in serum creatinine of ≥ 25% or 0.5 mg/dl from baseline within 1 week of contrast medium exposure.ResultsA total of 192 (8.7%) patients developed CI-AKI. No significant differences were observed in baseline patient characteristics between the statin and non-statin pretreatment groups after propensity score matching. In the propensity score-matched groups, the incidence of CI-AKI was significantly lower in patients with statin pretreatment than in those without statin pretreatment (3.5% vs.10.6%, odds ratio [OR]: 0.31, 95% confidence interval [CI]: 0.18–0.52, P < 0.001). Multivariate logistic regression analysis showed that statin pretreatment remained an independent negative predictor of CI-AKI (OR: 0.31, 95% CI: 0.18–0.53, P < 0.001) among propensity score-matched subjects.ConclusionsStatin pretreatment was associated with a significant decrease in the risk of CI-AKI in CAD patients undergoing PCI in the ICAS Registry
Anti-hypertensive effect of radiofrequency renal denervation in spontaneously hypertensive rats
AimsWe aimed to investigate the anti-hypertensive effect of radiofrequency (RF) renal denervation (RDN) in an animal model of hypertension.Materials and methodsRF energy was delivered to bilateral renal arteries through a 2Fr catheter with opening abdomen in 8 spontaneously hypertensive rats (SHRs) and 8 Wistar–Kyoto rats (WKYs). Sham operation was performed in other 8 SHRs and 8 WKYs. Blood pressure (BP), heart rate (HR), and urinary norepinephrine excretion were followed up for 3 months. Plasma and renal tissue concentrations of norepinephrine and plasma renin activity were measured 3 months after the procedure. The RDN was confirmed by a decrease in renal tissue norepinephrine.Key findingsRF-RDN restrained a spontaneous rise in systolic BP (46 ± 12% increase from 158 ± 8 to 230 ± 14 mm Hg vs. 21 ± 18% increase from 165 ± 9 to 197 ± 20 mm Hg, p = 0.01) and diastolic BP (55 ± 27% increase from 117 ± 9 to 179 ± 23 mm Hg vs. 28 ± 13% increase from 120 ± 7 to 154 ± 13 mm Hg, p = 0.04) in SHRs; however, WKYs were not affected. Although there were no changes in HR and systemic norepinephrine, the renal tissue norepinephrine was decreased by RF-RDN in both SHR (302 ± 41 vs. 159 ± 44 ng/g kidney, p < 0.01) and WKY (203 ± 33 vs. 145 ± 26 ng/g kidney, p = 0.01). Plasma renin activity was reduced by the RF-RDN only in SHR (35.3 ± 9.5 vs. 21.4 ± 8.6 ng/mL/h, p < 0.01).SignificanceRF-RDN demonstrated an anti-hypertensive effect with a reduction of renal tissue norepinephrine and plasma renin activity in SHR
Impact of Coronary Plaque Composition on Cardiac Troponin Elevation After Percutaneous Coronary Intervention in Stable Angina Pectoris : A Computed Tomography Analysis
ObjectivesThe authors used multidetector computed tomography (MDCT) to study the relation between culprit plaque characteristics and cardiac troponin T (cTnT) elevation after percutaneous coronary intervention (PCI).BackgroundPercutaneous coronary intervention is often complicated by post-procedural myocardial necrosis manifested by elevated cardiac biomarkers.MethodsStable angina patients (n = 107) with normal pre-PCI cTnT levels underwent 64-slice MDCT before PCI to evaluate plaque characteristics of culprit lesions. Patients were divided into 2 groups according to presence (group I, n = 36) or absence (group II, n = 71) of post-PCI cTnT elevation ≥3 times the upper limit of normal (0.010 ng/ml) at 24 h after PCI.ResultsComputed tomography attenuation values were significantly lower in group I than in group II (43.0 [26.5 to 75.7] HU vs. 94.0 [65.0 to 109.0] HU, p 1.05; odds ratio: 4.54; 95% confidence interval: 1.36 to 15.9; p = 0.014) and spotty calcification (odds ratio: 4.27; 95% confidence interval: 1.30 to 14.8; p = 0.016) were statistically significant independent predictors for cTnT elevation. For prediction of cTnT elevation, the presence of all 3 variables (CT attenuation value 1.05, and spotty calcification) showed a high positive predictive value of 94%, and their absence showed a high negative predictive value of 90%.ConclusionsMDCT may be useful in detecting which lesions are at high risk for myocardial necrosis after PCI
Superconductivity of Ti-Nb-Si Alloys Crystallized from the Amorphous State
This paper presents the relationship between superconducting properties and crystallization behavior of Ti-Nb-Si amorphous alloys. Continuous amorphous tapes with complete bend ductility were prepared in a limited composition range of Ti-Nb-Si ternary system. The superconducting properties (T_c, J_c and H_c) of these alloys improved remarkably on crystallization. The improvement in superconductivity after crystallization was attributed to the precipitation of a b. c. c. β-phase of titanium containing a large amount of niobium in solid solution. The T_c value increased with increasing niobium content and the highest value attained was about 9.9 K for Ti_ Nb_Si_ alloy annealed for 1 h at 1023 K. The same tendency was recognized for J_c and H_c, and the highest values were about 1.2×10^5 A/cm^2 at zero applied field and 4.2 K and more than about 7.2×10^6 A/m at 4.2 K for Ti_Nb_Si_. These values of T_c, J_c and H_c are almost of the same order as those of conventional superconducting Ti-Nb binary alloys. The easy formation of continuous amorphous tapes with highly ductile nature suggests the prospect of alternative methods for the production of superconducting materials
Structural phase diagram of LaO1-xFxBiSSe: suppression of the structural phase transition by partial F substitutions
We have investigated low-temperature crystal structure of BiCh2-based
compounds LaO1-xFxBiSSe (x = 0, 0.01, 0.02, 0.03, and 0.5), in which anomalous
two-fold-symmetric in-plane anisotropy of superconducting states has been
observed for x = 0.5. From synchrotron X-ray diffraction experiments, a
structural transition from tetragonal to monoclinic was observed for x = 0 and
0.01 at 340 and 240 K, respectively. For x = 0.03, a structural transition and
broadening of the diffraction peak were not observed down to 100 K. These facts
suggest that the structural transition could be suppressed by 3% F substitution
in LaO1-xFxBiSSe. Furthermore, the crystal structure for x = 0.5 at 4 K was
examined by low-temperature (laboratory) X-ray diffraction, which confirmed
that the tetragonal structure is maintained at 4 K for x = 0.5. Our results
suggest that the two-fold-symmetric in-plane anisotropy of superconducting
states observed for LaO0.5F0.5BiSSe was not originated from structural symmetry
lowering.Comment: 15 pages, 5 figures + 3 supplemental figure
Binocularly suppressed stimuli induce brain activities related to aesthetic emotions
Frontiers in Neuroscience. 2024, 18, 1339479journal articl
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