A Fully Automated Process Using a Magnetic Particle Based Kit for Removal of Dye Terminators from Sequencing Reactions

Prolinx,® Inc. of Bothell, WA has developed the RapXtract™ 384 Dye Terminator Removal Kit for full automation of DNA sequencing reaction purification. The RapXtract product line is based upon proprietary superparamagnetic particle technology that eliminates the need for centrifugation, vacuum filtration, or modified primers to achieve purification of sequencing reactions. The kit described here is pre-dispensed in a 384-well microtiter plate and run on the TECAN GENESIS Workstation 150 (Tecan U.S. Inc., Research Triangle Park, NC). This system enables rapid purification of up to 384 sequencing reactions in a single run.As the completion of the Human Genome Project nears, it is imperative for biotechnology and pharmaceutical companies to increase throughput of DNA sequencing in order to be competitive in the drug discovery and validation process. The “race to market” requires a shift from standard DNA sequencing processes-including DNA sequencing reaction purification-towards complete walk-away automation for all steps.Existing sequencing reaction purification methods (Table 1) require considerable resources including: plastic and other laboratory consumables; specialized equipment, such as high-speed centrifuges or vacuum filtration apparatus; and labor-intensive protocols requiring large amounts of technician time. As a result, walk-away automation of standard purification methods is difficult and expensive.     

Prediction of chromatographic retention and protein identification in liquid chromatography/mass spectrometry

Liquid chromatography coupled on- or off-line with mass spectrometry is rapidly advancing as a tool in proteomics capable of dealing with the inherent complexity in biology and complementing conventional approaches based on two-dimensional gel electrophoresis. Proteins can be identified by proteolytic digestion and peptide mass fingerprinting or by searching databases using short-sequence tags generated by tandem mass spectrometry. This paper shows that information on the chromatographic behavior of peptides can assist protein identification by peptide mass fingerprinting in liquid chromatography/mass spectrometry. This additional information is significant and already available at no extra experimental cost.     

The SARS Crisis: Was Anybody Responsible?

As scholars in fields such as media studies, crisis studies and public policy studies have argued, there exists a fundamental link between crises and the media. Once an event has been interpreted as a crisis, questions of accountability inevitably appear on the media agenda, and the struggle to attribute blame and responsibility to a specific entity or entities—the blame game—thus becomes an inexorable part of the crisis process. Focusing on three liberal Western newspapers with an international, primarily Western elite readership and a reputation for in‐depth analysis of global events, The Economist, the Financial Times and the International Herald Tribune, this article employs Iyengar's and Valkenburg's notions of responsibility frames to examine whether initial coverage of the 2003 SARS crisis in these accounts held any particular entity accountable for the crisis, looks at three key themes used to communicate to the reader a particular way of thinking about responsibility for SARS and examines some of the consequences of the kind of responsibility frame constructed around the SARS crisis in these accounts. As our findings show, there is an entity that the early news accounts studied consistently held responsible for the 2003 SARS crisis, the Chinese system, and the corresponding responsibility frame at operation in these accounts is thematic rather than episodic in nature, since it consistently places the SARS crisis within a broader context (a product of “China” itself and/or of societal‐governmental forces in China) rather than in relation to a specific episode or as the result of the particular actions of individuals. The SARS crisis narrative therefore presented in these accounts tells the story of an anachronistic Chinese system faced with a contemporary health threat that, by its very nature, it is incapable of assessing accurately or managing responsibly. By way of conclusion, we argue that, while the use of such a thematic frame to explain China's role in the 2003 SARS crisis may be accurate in certain respects, this frame falls short in other respects and proves particularly inadequate to the challenge of capturing the economic complexities of China's role during the crisis.     

Cocaine-conditioned place preference in young precocial domestic fowl.

Experiment 1 established conditioned place preference (CPP) control procedures for young precocial domestic fowl (test day age?=?13–25 days). Chicks displayed a preference (greater choice time) for white stimulus cards on first exposure to white versus red cards and equivalent preference for these stimulus cards after 6 exposures. Chicks in Experiment 2 displayed a cocaine CPP at each dose (0.5, 1.0, and 2.0 mg/kg intraperitoneally) after 6 cocaine-red card and 6 saline-white card pairings. This CPP decreased and was no longer significant over 2 additional nonreinforced test days. Experiment 3 results replicated the cocaine CPP (2.0 mg/kg) and demonstrated that the CPP did not develop when cocaine was administered several hours after card exposure. To our knowledge, these results are the first to demonstrate drug CPP in a nonmammalian model and support the notion that drug reinforcement processes are highly conserved. This precocial avian model may prove a useful addition to existing altricial models for the study of determinants of human drug use and abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gas chromatographic separation of linoleic acid hydroperoxides as trimethylsilyl ethers of methyl hydroxystearates

The primary products, 9- and 13-hydroperoxy-octadecadienoic acids, from lipoxygenase catalyzed oxidation of linoleic acid, were converted into the trimethylsilyl ethers of methyl 9- and 13-hydroxystearates which were completely separated by gas chromatography on an OV-17 methyl silicone (50% phenyl groups), capillary column.     

Do work technique and musculoskeletal symptoms differ between men and women performing the same type of work tasks?

Musculoskeletal disorders are more common among women than among men. When comparing the difference between men and women in the prevalence of musculoskeletal disorders, methodological problems arise as men and women seldom perform the same type of activities, neither at work nor at home.

The main objective of this cross-sectional case study was to compare work technique and self-reported musculoskeletal symptoms between men and women performing the same type of work tasks within a metal industry. Other factors, such as leisure activities, were also taken into consideration. Three data collection methods were used; questionnaire, interviews and systematic observations. The results from the observations revealed that women worked more frequently and during longer times with their hands above shoulder height than men. Working with hands above shoulder height is considered a risk factor for neck and shoulder disorders according to previous studies. Workplace design factors were probably a reason for differences in working technique between men and women. A higher proportion of women than men reported shoulder symptoms. Women spent more time on household activities than men, which indicates a higher total workload in paid and unpaid work.     

Simple and comprehensive two-dimensional reversed-phase HPLC using monolithic silica columns

Simple and comprehensive two-dimensional (2D)-HPLC was studied in a reversed-phase mode using monolithic silica columns for second-dimension (2nd-D) separation. Every fraction from the first column, 15 cm long (4.6-mm i.d.), packed with fluoroalkylsilyl-bonded (FR) silica particles, was subjected to the separation in the 2nd-D using one or two octadecylsilylated (C(18)) monolithic silica columns (4.6-mm i.d., 3 cm). Monolithic silica columns in the 2nd-D were eluted at a flow rate of up to 10 mL/min with separation time of 30 s that meets the fractionation every 15-30 s at the first dimension (1st-D) operated at a flow rate of 0.4-0.8 mL/min. Three cases were studied. (1) In the simplest scheme of 2D-HPLC, effluent of the 1st-D was directly loaded into an injector loop of 2nd-D HPLC for 28 s, and 2 s was allowed for injection. (2) Two six-port valves each having a sample loop were used to hold the effluent of the 1st-D alternately for 30 s for one 2nd-D column to effect comprehensive 2D-HPLC without the loss of 1st-D effluent. (3) Two monolithic silica columns were used for 2nd-D by using a switching valve and two sets of 2nd-D chromatographs separating each fraction of the 1st-D effluent with the two 2nd-D columns alternately. In this case, two columns of the same stationary phase (C(18)) or different phases, C(18) and (pentabromobenzyloxy)propylsilyl-bonded (PBB), could be employed at the 2nd-D, although the latter needed two complementary runs. The systems produced peak capacity of approximately 1000 in approximately 60 min in cases 1 and 2 and in approximately 30 min in case 3. The three stationary phases, FR, C(18), and PBB, showed widely different selectivity from each other, making 2D separations possible. The simple and comprehensive 2D-HPLC utilizes the stability and high efficiency at high linear velocities of monolithic silica columns.     

A faster approach to infrared rheo-optics using a planar array infrared spectrograph

Infrared rheo-optics combines dynamic mechanical analysis with infrared spectroscopy to provide molecular level information about the segmental reorientation and the changes in local environment associated with the dynamic deformation of polymers. Up to now, the application of this technique has been limited by the amount of time necessary to perform the experiments. In this article, we demonstrate that the use of a planar array infrared (PA-IR) spectrograph can accelerate the acquisition time by as much as two orders of magnitude while maintaining a signal-to-noise ratio (SNR) similar to that obtained using step-scan Fourier transform infrared (FT-IR) spectrometry, and by more than three orders of magnitude at the expense of a reduced SNR. The advantages and drawbacks of this new technique are discussed.