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61.

Objectives

The influence of dentin adhesive systems (Scotchbond Multi-Purpose, XP Bond, Xeno V, Clearfil Protect Bond, AdheSE) on cell survival, viability and proliferation was characterized after direct and indirect exposure using different cell culture techniques.

Materials and methods

The primers and cured bonding parts were directly exposed to cells using cell culture inserts, and complete materials were analyzed in a dentin barrier test. Cell responses were examined in 3T3 mouse fibroblasts after 24- and 72-h exposure periods by the estimation of total cell numbers (survival), apoptosis (viability) and cell proliferation.

Results

Cell numbers were effectively reduced by the primers of AdheSE, Protect Bond, and Scotchbond Multi-Purpose as well as XP bond after direct exposure in a cell culture insert test device. Likewise, Scotchbond Multi-Purpose primer induced a rate of apoptosis (93.9%) even higher than detected with Protect Bond primer (91.6%). Cell proliferation was entirely inhibited by primers and by Xp Bond as well. The Scotchbond Multi-Purpose was most cytotoxic in a dentin barrier test device after a 24-h indirect exposure. It also increased the percentage of cells in apoptosis to 15.4% compared to untreated controls.

Conclusion

Unpolymerized primers of dentin adhesives were more cytotoxic than polymerized bonding counterparts. Moreover, total etch dentin adhesives were more cytotoxic than self-etch adhesives.

Clinical relevance

When dentin adhesives are used in deep cavities without a protective dentin barrier the leachable hydrophobic and hydrophilic component of dentin adhesive systems can penetrate to the pulp and may induce cytotoxic responses in pulp tissues.  相似文献   
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To investigate the efficacy of phonophoresis with nonsteroid anti-inflammatory drugs (P-NSAID) and corticosteroids (P-CS) in the treatment for carpal tunnel syndrome (CTS) and to compare the efficacy of phonophoresis with local CS injection (LCSI) and splinting with a 3-month follow-up. 84 hands of 51 patients with CTS were treated by applying LCSI, P-CS, P-NSAID, and wrist splinting. Electrophysiological studies, grip strength, hand dexterity, and sensory recovery of the first three digits were assessed. Duru?z hand index (DHI) was used to assess the functional hand disability. For clinical evaluation, we used Phalen and Tinnel signs. Pain intensity was evaluated by visual analog scale. The LCIS group showed a significant improvement in pain relief and DHI, but this group had significant deterioration in the results of monofilament and pegboard tests. The P-CS group showed improvement in sensory nerve conduction velocity, distal latency, grip strength, and DHI parameters. There was a significant improvement in grip strength, pegboard test, and pain intensity in the P-NSAID group. There was improvement only in pain intensity in the splinting group. We identified marked improvement in the electrophysiological studies in the P-CS group. Splinting had no effect on hand functions, disability, and electrophysiological studies.  相似文献   
64.
Aspiration is a serious complication of gastrointestinal (GI) decontamination procedure. Studies have shown that tumor necrosis factor-α (TNF-α) blockers have beneficial effects on lung injury. Therefore, the authors investigated the attenuation by infliximab (INF) on activated charcoal (AC)- and polyethylene glycol (PEG)-induced lung injury in rat model. Forty-two male Sprague-Dawley rats were allotted into 1 of 6 groups: saline (NS), activated charcoal (AC), polyethylene glycol (PEG), NS+INF treated, AC+INF treated, and PEG+INF treated. All materials were aspirated into the lungs at a volume of 1 mL/kg. Before aspiration, the rats were injected subcutaneously with INF. Seven days later, both lungs and serum specimens in all groups were evaluated histopathologically, immunohistochemically, and biochemically. Following aspiration of AC and PEG, evident histopathological changes were assigned in the lung tissue that were associated with increased expression of inducible nitric oxide synthase (iNOS), increased serum levels of oxidative stress markers (malondialdehyde [MDA], surfactant protein-D [SP-D], TNF-α), and decreased antioxidant enzyme (glutathione peroxidase [GSH-Px]) activities. INF treatment significantly decreased the elevated serum MDA and TNF-α levels and increased serum GSH-Px levels. Furthermore, the current results show that there is a significant reduction in the activity of iNOS in lung tissue and increased serum SP-D levels of AC and PEG aspiration-induced lung injury with INF treatment. These findings suggest that INF attenuates lung inflammation and prevents GI decontamination agent-induced lung injury in rats.  相似文献   
65.
Introduction and Objective: The present study aims to quantitatively evaluate the right ventricle (RV) function by means of transthoracic echocardiography in normal children and childhood congenital heart disease patients with pulmonary hypertension. Patients and Methods: This study was conducted in a cohort including 40 healthy children and 30 pediatric patients with pulmonary hypertension who were diagnosed under close surveillance at the study center between October 2009 and November 2010. Results: Statistically significant differences were found between the patient and control groups for the right ventricle myocardial performance index (RVMPI), the left ventricle myocardial performance index (LVMPI), the tricuspid valve systolic flow velocity (Ts), the ratio of systolic pulmonary artery pressure to the right ventricle outflow tract systolic flow velocity time integral (sPAP/RVOT VTI), and the ratio of systolic pulmonary artery pressure to right ventricle outflow tract systolic flow velocity time integral × heart rate (sPAP/[RVOT VTI×HR]). When the children were divided into three groups based on their pulmonary vascular resistance significant differences emerged that predicted an increasing severity of RV dysfunction. Significant differences were also observed for the RVMPI, the LVMPI, and the Ts as well as for echocardiographic pulmonary flow (Qp) and systemic flow (Qs). Discussion: The present study demonstrates that echocardiographic parameters can be used for the quantitative detection of RV dysfunction in childhood congenital heart disease patients with high pulmonary artery pressure (systolic, diastolic, and mean) or pulmonary vascular resistance.  相似文献   
66.

OBJECTIVES:

Acute ST-elevation myocardial infarction is associated with ventricular dysfunction due to ischemia-induced progressive myocardial damage. The decrease in ventricular compliance causes left atrial dilatation and stretching of the atrial myocardium, which are the main stimuli for the secretion of atrial natriuretic peptide. The aim of this study was to evaluate left atrial dimensions and atrial natriuretic peptide levels in patients early after their first acute ST-elevation myocardial infarction and assess the probable interaction between coronary lesions and these measurements.

METHODS:

A total of 110 patients with acute myocardial infarction and 50 controls were studied. Plasma atrial natriuretic peptide was measured at admission. Left ventricular function, diameter, and volume index were evaluated using transthoracic echocardiography. Gensini and vessel scores of the patients who underwent coronary angiography were calculated.

RESULTS:

Plasma atrial natriuretic peptide in the patients with myocardial infarction was increased compared with that in controls (3.90±3.75 vs. 1.35±0.72 nmol/L, p<0.001). Although the left atrial diameter was comparable in patients and controls, the left atrial volume index was increased in patients with acute myocardial infarction (26.5±7.1 vs. 21.3±4.9 mL/m2, p<0.01). Multivariate regression analysis showed a strong independent correlation between the left atrial volume index and the plasma atrial natriuretic peptide level (β = 0.23, p = 0.03).

CONCLUSIONS:

The left atrial volume index and plasma atrial natriuretic peptide level were correlated in patients with acute myocardial infarction.  相似文献   
67.
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69.
Background: A tombstoning pattern (T‐pattern) is associated with in‐hospital poor outcomes patients with ST‐segment elevation myocardial infarction (STEMI), but no data are available for midterm follow‐up. We sought to determine the prognostic value of a T‐pattern on admission electrocardiography (ECG) for in‐hospital and midterm mortality in patients with anterior wall STEMI treated with primary percutaneous coronary intervention (PCI). Methods: After exclusion, 169 consecutive patients with anterior wall STEMI (mean age: 55 ± 12.9 years; 145 men) undergoing primary PCI were prospectively enrolled in this study. Patients were classified as a T‐pattern (n = 32) or non–T‐pattern (n = 137) based upon the admission ECG. Follow‐up to 6 months was performed. Results: In‐hospital mortality tended to be higher in the T‐pattern group compared with non–T‐pattern group (9.3% vs 2.1% respectively, P = 0.05). All‐cause mortality was higher in the T‐pattern group than non–T‐pattern group for 6 month (P = 0.004). After adjusting the baseline characteristics, the T‐pattern remained an independent predictor of 6‐month all‐cause mortality (odds ratio: 5.18; 95% confidence interval: 1.25–21.47, P = 0.02). Conclusion: A T‐pattern is a strong independent predictor of 6‐month all‐cause mortality in anterior STEMI treated with primary PCI. Therefore, it may be an indicator of high risk among patients with anterior wall STEMI.  相似文献   
70.
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