European Heart and Rhythm Association guidelines on new oral anticoagulants: A bold step forward

[Rate and rhythm control in atrial fibrillation : pharmacological approaches]

Atrial fibrillation is the most common form of cardiac arrhythmia, occurring in 1-2 % of the population and due to an increased life expectancy the prevalence will increase further. Pharmacological treatment of atrial fibrillation is an important component of basic initial therapeutic options for patients with atrial fibrillation. Independent of an individually adjusted prevention of thromboembolism, rate and rhythm management can also be carried out. While rate control mainly applies to all patients, rhythm control is only indicated in patients who remain clinically symptomatic despite sufficient rate control. Profound knowledge about antiarrhythmic drugs including specific interactions is necessary due to the variable individual effects and sometimes severe side effects.

Biochemistry and biology of mammalian DNA methyltransferases

DNA methylation is a stable but not irreversible epigenetic signal that silences gene expression. It has a variety of important functions in mammals, including control of gene expression, cellular differentiation and development, preservation of chromosomal integrity, parental imprinting and X-chromosome inactivation. In addition, it has been implicated in brain function and the development of the immune system. Somatic alterations in genomic methylation patterns contribute to the etiology of human cancers and ageing. It is tightly interwoven with the modification of histone tails and other epigenetic signals. Here we review our current understanding of the molecular enzymology of the mammalian DNA methyltransferases Dnmt1, Dnmt3a, Dnmt3b and Dnmt2 and the roles of the enzymes in the above-mentioned biological processes.