Background: Replication of influenza virus to high titer is a prerequisite for successful cell-based vaccine production. Entry of virus into the cell depends on the cleavage of the hemagglutinin precursor (HA0) protein mediated by trypsin. Objectives: The aim of the present study was to apply a technique to establish MDCK/FX manipulated cell, which may provide a new platform for developing influenza vaccine based on the cell culture approaches. Methods: Chicken embryo FX expressed into the pCDNA3. 1 vector was transfected into the MDCK cell line. The longevity of the geneRATEd cell and the viable cell density were evaluated for 17 passages prior to virus inoculation. Then, the ability of MDCK/FX cell for efficient replication of H9N2 influenza virus was evaluated by viral titration and quantitative RT-PCR. Results: RT-PCR data revealed that FX was stably expressed in the cell after the subsequent passages without any change in the RATE of culture’ s confluency. Growth kinetic of H9N2 virus analysis demonstRATEd that MDCK/FX cell supported high-titer growth of the virus in which the viral titer is comparable to the virus grown in MDCK cells supplemented with TPCK-trypsin. Quantification of influenza infectious particles in the cell culture revealed the equivalents viral RNA copies and viral titers. Conclusions: The results indicated a potential application for the MDCK/FX in influenza virus replication procedure and related studies.

Background and Aim: Toothbrushing can potentially abrade the teeth and direct and indirect dental restorations, and may also affect their color. This study aimed to assess the color change (Δ, E) of Ceramill Zolid FX following abrasion with/without toothpaste in two groups of simultaneous and sepaRATE staining and glazing. Materials and Methods: This in vitro, experimental study was conducted on 40 cylindrical specimens measuring 2 x 10 mm fabricated from Ceramill Zolid FX by the computer-aided design/computer-aided manufacturing technology. The samples were randomly divided into four groups (simultaneous and sepaRATE staining and glazing) and subjected to simulation of 3, 6 and 9 years of toothbrushing in a cross-brushing machine with and without toothpaste. The Δ, E of specimens was measured before and after the intervention by using Shade Pilot spectrophotometer, and compared using the Mann-Whitney and Friedman tests (alpha=0. 05). Results: Significant differences were noted in Δ, E of simultaneous staining and glazing control (without toothpaste) and intervention (with toothpaste) groups over time (both P=0. 000). Both the control and intervention subgroups in sepaRATE staining and glazing group also showed significant differences in Δ, E over time (both P=0. 000). Conclusion: The results showed greater color change over time in simultaneous staining and glazing group due to the presence of one layer of stain and glaze, compared with sepaRATE staining and glazing. The effect of toothpaste on color change was only significant at 9 years in both simultaneous and sepaRATE staining and glazing groups.

In searching a market-neutral arbitrage stRATEgy in forex market, we took a portfolio of three major currency pairs, EUR-USD, USD-JPY, and EUR-JPY. There are eight approaches, different cases of short and long positions; for example buying 1st and selling two others, etc.Historical daily FX RATEs were gathered since January 1990 until February 2011. Monthly covariances between daily growth RATE of FX RATEs and monthly means of profit or loss of all approaches were calculated. Some different tests were applied.Eight approaches have been compared with each other in 28 states. Compared profit or loss of approaches in each state was calculated.With an ANOVA test, we found that the difference between means of approaches was significant. We found that covariance’s often tend to be only positive or negative. We categorized different cases of covariances on the basis of its positive or negative signs in four categories. In each category, means of eight approaches were calculated and they have been compared binarilyin 28 states. There were relations between conditions of the categories (their negative or positive signs) and results of different approaches derived.It has been recommended to use a covariance indicator in forex softwares to make better orders.With computing the weighted average of approaches (on the basis of occurrence ratio of category) we found that BSS (buying 1st and selling the two others) and SSS (selling all the pairs) were the best approaches. They are not completely neutral, but in most of the time, they can eventuate to profit.