Metal ion release from silver soldering and laser welding caused by different types of mouthwash

Objective:To compare metal ion release from samples welded with silver soldering and laser welding when immersed into mouthwashes with different ingredients.Materials and Methods:A total of 72 samples were prepared: 36 laser welded and 36 silver soldered. Four samples were chosen from each subgroup to study the morphologic changes on their surfaces via scanning electron microscopy (SEM). Each group was further divided into four groups where the samples were submerged into mouthwash containing sodium fluoride (NaF), mouthwash containing sodium fluoride + alcohol (NaF + alcohol), mouthwash containing chlorhexidine (CHX), or artificial saliva (AS) for 24 hours and removed thereafter. Subsequently, the metal ion release from the samples was measured with inductively coupled plasma mass spectrometry (ICP-MS). The metal ion release among the solutions and the welding methods were compared. The Kruskal-Wallis and analysis of variance (ANOVA) tests were used for the group comparisons, and post hoc Dunn multiple comparison test was utilized for the two group comparisons.Results:The level of metal ion release from samples of silver soldering was higher than from samples of laser welding. Furthermore, greater amounts of nickel, chrome, and iron were released from silver soldering. With regard to the mouthwash solutions, the lowest amounts of metal ions were released in CHX, and the highest amounts of metal ions were released in NaF + alcohol. SEM images were in accord with these findings.Conclusions:The laser welding should be preferred over silver soldering. CHX can be recommended for patients who have welded appliances for orthodontic reasons.     

N-acetylcysteine for the prevention of postoperative atrial fibrillation: a prospective, randomized, placebo-controlled pilot study.

AIMS: Oxidative stress has recently been implicated in the pathophysiology of atrial fibrillation (AF). The aim of the present study was to evaluate the effects of antioxidant agent N-acetylcysteine (NAC) on postoperative AF. METHODS AND RESULTS: The population of this prospective, randomized, double-blind, placebo-controlled study consisted of 115 patients undergoing coronary artery bypass and/or valve surgery. All the patients were treated with standard medical therapy and were randomized to NAC group (n = 58) or placebo (saline, n = 57). An AF episode >5 min during hospitalization was accepted as endpoint. During follow-up period, 15 patients (15/115, 13%) had AF. The rate of AF was lower in NAC group compared with placebo group (three patients in NAC group [5.2%] and 12 patients in placebo group [21.1%] had postoperative AF; odds ratio [OR] 0.20; 95% confidence interval [CI] 0.05 to 0.77; P = 0.019). In the multivariable logistic regression analysis, independent predictors of postoperative AF were left atrial diameter (OR, 1.18; 95% CI, 1.06-1.31; P = 0.002) and the use of NAC (OR, 0.20; 95% CI, 0.04-0.91; P = 0.038). CONCLUSION: The result of this study indicates that NAC treatment decreases the incidence of postoperative AF.     

Lysophosphatidylcholine-induced modulation of Ca(2+)-activated K(+)channels contributes to ROS-dependent proliferation of cultured human endothelial cells

Proliferation of endothelial cells plays a crucial role in the process of atherosclerotic plaque destabilization. The major component of oxidized low-density lipoprotein lysophosphatidylcholine (LPC) has been shown to promote endothelial proliferation by increasing the production of reactive oxygen species (ROS). Since K(+) channels are known to control the cell cycle, we investigated the role of Ca(2+)-activated K(+) channels (BK(Ca)) in the regulation of LPC-induced endothelial proliferation and ROS generation. A significant increase of cell growth induced by LPC (20 micromol/l; cell counts (CCs): +87%, thymidin incorporation: +89%; n = 12, P < 0.01) was observed, which was inhibited by the BK(Ca) inhibitor iberiotoxin (IBX; 100 nmol/l), by the NAD(P)H-oxidase inhibitor diphenyleneiodonium (5 micromol/l) and by transfection with antisense (AS) oligonucleotides against NAD(P)H oxidase, whereas N(G)-monomethyl-l-arginine (l-NMMA) further increased LPC-induced cell growth. Using the patch-clamp technique a significant increase of BK(Ca) open-state probability (control: 0.004 +/- 0.002; LPC: 0.104 +/- 0.035; n = 21, P < 0.05) by LPC was observed. Using dichlorofluorescein fluorescence microscopy a significant increase of ROS induced by LPC was reported, that was blocked by IBX and Ca(2+) antagonists. Intracellular Ca(2+) measurements revealed a capacitative Ca(2+) influx caused by LPC. Bioactivity of nitric oxide (NO) was measured using a [(3)H]-cGMP radioimmunoassay. LPC significantly decreased acetylcholine-induced NO synthesis. LPC significantly increased cGMP levels in endothelial cells transfected with AS, which was blocked by IBX. In conclusion, our results demonstrate that LPC activates BK(Ca) thereby increasing ROS production which induces endothelial proliferation. In addition LPC-induced BK(Ca)-activation contributes to increased cGMP levels, if ROS production is prevented by AS.     

Tyrosinase and Cholinesterase Inhibitory Potential and Flavonoid Characterization of Viola odorata L. (Sweet Violet)

Inhibitory potential of the dichloromethane, ethyl acetate, ethanol, and aqueous extracts of Viola odorata L. (VO) was investigated against tyrosinase (TYR) and cholinesterases by microplate assays. The antioxidant activity was tested using six in vitro assays. Only the ethanol extract inhibited TYR (80.23 ± 0.87% at 100 µg mL^?1), whereas none of them were able to inhibit cholinesterases. The extracts were more able to scavenge NO radical (31.98 ± 0.53–56.68 ± 1.10%) than other radicals tested, and displayed low to moderate activity in the rest of the assays. HPLC analysis revealed that the aqueous extract of VO contained a substantial amount of vitexin (18.81 ± 0.047 mg g^?1 extract), while the ethanol extract also possessed rutin (1.31 ± 0.013 mg g^?1 extract) and vitexin (4.65 ± 0.103 mg g^?1 extract). Furthermore, three flavonoids (rutin, isovitexin, and kaempferol‐6‐glucoside) were isolated from the ethanol extract. This is the first report on TYR inhibitory activity of VO as well as presence of vitexin and isovitexin in this species. Copyright © 2015 John Wiley & Sons, Ltd.     

Electrophysiological Heterogeneity of Atrial Fibrillation and Local Effect of Propafenone in the Human Right Atrium: Analysis Based on Symbolic Dynamics

A recently developed algorithm that is based on symbolic dynamics and computation of the normalized algorithmic complexity (C) was applied to basket-catheter mapping of the atrial fibrillation (AF). The aim of our study was to analyze the spatial distribution of the C during AF and effects of propafenone on this distribution. During right atrial mapping in 25 patients with AF 31 intra-atrial and 1 surface bipolar channels were acquired. The anatomical location of the intra-atrial electrodes was defined fluoroscopically. C was calculated for a moving window (size: 2000 points; step 500 points). Generated C was analyzed within 10 minutes before and after administration of propafenone. The inter-regional C distribution was analyzed using the Friedman-test (intra-individually) and Kruskall-Wallis-H-test (inter- individually). A value of p=0.05 was set for an error probability. Inter-regional C differences were found in all patients (p<0.001). The right atrium could be divided in high- and low complexity areas according to individual patterns. A significant C increase in cranio-caudal direction (with the exception of septum) was confirmed inter-individually (p<0.01). The administration of propafenone enlarged the areas of low complexity.Conclusions: This new method utilizing the combination of symbolic dynamics and adaptive power estimation can provide complex evaluation of the dynamics of AF in man. High-density mapping will be required for further evaluation of results.     

Impact of the age of stored blood on trauma patient mortality: a systematic review

Background

The impact of the age of stored red blood cells on mortality in patients sustaining traumatic injuries requiring transfusion of blood products is unknown. The objective of this systematic review was to identify and describe the available literature on the use of older versus newer blood in trauma patient populations.

Methods

We searched PubMed, Embase, Lilac and the Cochrane Database for published studies comparing the transfusion of newer versus older red blood cells in adult patients sustaining traumatic injuries. Studies included for review reported on trauma patients receiving transfusions of packed red blood cells, identified the age of stored blood that was transfused and reported patient mortality as an end point. We extracted data using a standardized form and assessed study quality using the Newcastle–Ottawa Scale.

Results

Seven studies were identified (6780 patients) from 3936 initial search results. Four studies reported that transfusion of older blood was independently associated with increased mortality in trauma patients, while 3 studies did not observe any increase in patient mortality with the use of older versus newer blood. Three studies associated the transfusion of older blood with adverse patient outcomes, including longer stay in the intensive care unit, complicated sepsis, pneumonia and renal dysfunction. Studies varied considerably in design, volumes of blood transfused and definitions applied for old and new blood.

Conclusion

The impact of the age of stored packed red blood cells on mortality in trauma patients is inconclusive. Future investigations are warranted.