1.Highly Efficient Synthesis of an Emerging Lipophilic Antioxidant: 2-Ethylhexyl Ferulate.
Huang KC1, Li Y2, Kuo CH3, Twu YK4, Shieh CJ5. Molecules. 2016 Apr 12;21(4). pii: E478.
Ferulic acid in ester form has shown a stronger ability in ameliorating certain pathological conditions and inhibiting lipid oxidation. In present study, a solvent-free and reduced pressure evaporation system was developed for lipase-catalyzed synthesis of 2-ethylhexyl ferulate (2-EF) from ferulic acid and 2-ethylhexanol. A Box-Behnken design with response surface methodology (RSM) and artificial neural network (ANN) was selected to model and optimize the process. Based on the yields of 2-EF, reaction temperature was shown to be the most important process factor on the molar conversion among all variables. The residual values and the coefficient of determination (R²) calculated from the design data indicated that ANN was better than RSM in data fitting. Overall, the present lipase-catalyzed approach for 2-EF synthesis at low reaction temperature in a reduced pressure evaporation system shows high 2-EF production efficiency. Notably, this approach can reduce the enzyme denaturation and ferulic acid oxidation that usually occur during long-term biosynthetic operations at high temperature.
2.Evaluation of bias associated with high-multiplex, target-specific pre-amplification.
Okino ST1, Kong M1, Sarras H2, Wang Y1. Biomol Detect Quantif. 2015 Dec 21;6:13-21. doi: 10.1016/j.bdq.2015.12.001. eCollection 2016.
We developed a novel PCR-based pre-amplification (PreAmp) technology that can increase the abundance of over 350 target genes one million-fold. To assess potential bias introduced by PreAmp we utilized ERCC RNA reference standards, a model system that quantifies measurement error in RNA analysis. We assessed three types of bias: amplification bias, dynamic range bias and fold-change bias. We show that our PreAmp workflow introduces only minimal amplification and fold-change bias under stringent conditions. We do detect dynamic range bias if a target gene is highly abundant and PreAmp occurred for 16 or more PCR cycles; however, this type of bias is easily correctable. To assess PreAmp bias in a gene expression profiling experiment, we analyzed a panel of genes that are regulated during differentiation using the NTera2 stem cell model system. We find that results generated using PreAmp are similar to results obtained using standard qPCR (without the pre-amplification step).
3.Mechanisms of Lipid Accumulation in the Bone Morphogenic Protein Receptor 2 Mutant Right Ventricle.
Talati MH1, Brittain EL2, Fessel JP3, Penner N4, Atkinson J5, Funke M6, Grueter C7, Jerome WG8, Freeman M9, Newman JH10, West J11, Hemnes AR12. Am J Respir Crit Care Med. 2016 Apr 14. [Epub ahead of print]
RATIONALE: In heritable pulmonary arterial hypertension (HPAH) with germline mutation in the bone morphogenetic protein receptor 2 (BMPR2) gene, right ventricular (RV) dysfunction is associated with RV lipotoxicity, however the underlying mechanism for lipid accumulation is not known.
4.Multiple Natural Substitutions in Avian Influenza A Virus PB2 Facilitate Efficient Replication in Human Cells.
Mänz B1, de Graaf M1, Mögling R1, Richard M1, Bestebroer TM1, Rimmelzwaan GF1, Fouchier RA2. J Virol. 2016 Apr 13. pii: JVI.00130-16. [Epub ahead of print]
A strong restriction of the avian influenza A virus polymerase in mammalian cells generally limits viral host-range switching. Although substitutions like E627K in the PB2 polymerase subunit can facilitate polymerase activity to allow replication in mammals, many human H5N1 and H7N9 viruses lack this adaptive substitution. Here, several previously unknown, naturally occurring, adaptive substitutions in PB2 were identified by bioinformatics, and their enhancing activity verified usingin vitroassays. Adaptive substitutions enhanced polymerase activity and virus replication in mammalian cells for avian H5N1 and H7N9 viruses, but not for a partially human-adapted H5N1 virus. Adaptive substitutions towards basic amino acids were frequent and were mostly clustered in a putative RNA exit channel in a polymerase crystal structure. Phylogenetic analysis demonstrated divergent dependency of influenza viruses on adaptive substitutions. The novel adaptive substitutions found in this study increase basic understanding of influenza virus host adaptation and will help in surveillance efforts.
