A high efficient protocol for soybean root transformation by Agrobacterium rhizogenes and most stable reference genes for RT-qPCR analysis.

KEY MESSAGE: A 55% transformation efficiency was obtained by our optimized protocol; and we showed that GmELF1 - ß and GmELF1 - α are the most stable reference genes for expression analyses under this specific condition. Gene functional analyses are essential to the validation of results obtained from in silico and/or gene-prospecting studies. Genetic transformation methods that yield tissues of transient expression quickly have been of considerable interest to researchers. Agrobacterium rhizogenes-mediated transformation methods, which are employed to generate plants with transformed roots, have proven useful for the study of stress caused by root phytopathogens via gene overexpression and/or silencing. While some protocols have been adapted to soybean plants, transformation efficiencies remain limited; thus, few viable plants are available for performing bioassays. Furthermore, mRNA analyses that employ reverse transcription quantitative polymerase chain reactions (RT-qPCR) require the use of reference genes with stable expression levels across different organs, development steps and treatments. In the present study, an A. rhizogenes-mediated soybean root transformation approach was optimized. The method delivers significantly higher transformation efficiency levels and rates of transformed plant recovery, thus enhancing studies of soybean abiotic conditions or interactions between phytopathogens, such as nematodes. A 55% transformation efficiency was obtained following the addition of an acclimation step that involves hydroponics and different selection processes. The present study also validated the reference genes GmELF1-ß and GmELF1-α as the most stable to be used in RT-qPCR analysis in composite plants, mainly under nematode infection.

A randomized trial of the peri-operative use of COX-2 inhibitors in Lichtenstein herniorrhaphy.

INTRODUCTION: We present a randomized controlled trial to evaluate the value of the cyclo-oxygenase-2 (COX-2) inhibitor, rofecoxib, as an adjuvant for pain management for patients undergoing a conventional Lichtenstein inguinal herniorrhaphy. The drug was removed from the market coincidentally with the conclusion of the trial due to thrombotic complications. We believe that the data remains important, however, because of the imminent release of similar compounds with a better safety profile. No industry support was sought or accepted for this trial, with the exception of the study drug and an identical placebo preparation supplied by Merck in a completely unrestricted agreement. METHODS AND MATERIALS: Seventy-nine patients were recruited for the single-center randomized controlled double blinded trial, with 27 receiving placebo, 26 who received rofecoxib only in the post-operative period, and 26 who received rofecoxib both in the pre- and post-operative period. The patients were followed for 6 weeks with serial administration of the short form 36 health survey questionnaire (SF-36), visual analog scale (VAS) questionnaire, and activity restriction questionnaire. Statistical analysis was performed using multivariate generalized estimating equations in a blinded fashion. RESULTS: The mean pain over time decreased over the 6 weeks and was significantly lower in the group that received rofecoxib in the post-operative period than the other two groups (P = 0.02). The number of rescue narcotic medications taken by patients on day 1 were 3.0 (2.4) [mean (SD)] in the placebo group, 2.2 (1.7) (P < 0.001) in the post-operative only group, and 2.9 (2.3) (P = 0.37) in the peri-operative group. There was no statistical significance between the physical health composite scores or the mental health composite scores at 6 weeks. CONCLUSION: The use of post-operative rofecoxib decreases the amount of pain post-operatively after inguinal herniorrhaphy and decreases the number of rescue narcotic medications used, but it does not change the quality of life. This effect is lacking in the peri-operative group. There is no evidence to recommend the routine use of rofecoxib or similar COX-2 inhibitors after inguinal hernia surgery.

Heidegger's relevance for engineering: questioning technology.

Heidegger affirmed traditional technology, but was opposed to science-based modern technology, in which everything (including man) is considered to be a mere "resource". This opposition was expressed in the form of deep questioning and a suspicion of superficial evaluation, because the true nature of things was often concealed, though disclosed at times. Ways in which engineers should question technology are proposed, highlighting some of the hazards and injustices associated with technology and also its subtle sociological and psychological influences. The demands of engineering ethics and the use of metaphor in design are other ways in which a narrowly rationalistic technological outlook can be confronted.