Animal models of arrhythmia: classic electrophysiology to genetically modified large animals

Engineered nucleases that cleave specific DNA sequences in vivo are valuable reagents for targeted mutagenesis. Here we report a new class of sequence-specific nucleases created by fusing transcription activator-like effectors (TALEs) to the catalytic domain of the FokI endonuclease. Both native and custom TALE-nuclease fusions direct DNA double-strand breaks to specific, targeted sites.

Swine are considered to be one of the major animal species used in translational research, surgical models, and procedural training and are increasingly being used as an alternative to the dog or monkey as the choice of nonrodent species in preclinical toxicologic testing of pharmaceuticals. There are unique advantages to the use of swine in this setting given that they share with humans similar anatomic and physiologic characteristics involving the cardiovascular, urinary, integumentary, and digestive systems. However, the investigator needs to be familiar with important anatomic, histopathologic, and clinicopathologic features of the laboratory pig and minipig in order to put background lesions or xenobiotically induced toxicologic changes in their proper perspective and also needs to consider specific anatomic differences when using the pig as a surgical model. Ethical considerations, as well as the existence of significant amounts of background data, from a regulatory perspective, provide further support for the use of this species in experimental or pharmaceutical research studies. It is likely that pigs and minipigs will become an increasingly important animal model for research and pharmaceutical development applications.

To describe the effect of atrial fibrillation on long-term morbidity and mortality. The Renfrew/Paisley Study surveyed 7052 men and 8354 women aged 45-64 years between 1972 and 1976. All hospitalizations and deaths occurring during the subsequent 20 years were analyzed by the presence or absence of atrial fibrillation at baseline. Lone atrial fibrillation was defined in the absence of other cardiovascular signs or symptoms. Cox proportional hazards models were used to adjust for age and cardiovascular conditions. After 20 years, 42 (89%) of the 47 women with atrial fibrillation had a cardiovascular event (death or hospitalization), compared with 2276 (27%) of the 8307 women without this arrhythmia. Among men, 35 (66%) of 53 with atrial fibrillation had an event, compared with 3151 (45%) of 6999 without atrial fibrillation. In women, atrial fibrillation was an independent predictor of cardiovascular events (rate ratio [RR] = 3.0; 95% confidence interval [CI]: 2.1-4.2), fatal or nonfatal strokes (RR = 3.2; 95% CI: 1.0-5.0), and heart failure (RR = 3.4; 95% CI: 1.9-6.2). The rate ratios among men were 1.8 (95% CI: 1.3-2.5) for cardiovascular events, 2.5 (95% CI: 1.3-4.8) for strokes, and 3.4 (95% CI: 1.7-6.8) for heart failure. Atrial fibrillation was an independent predictor of all-cause mortality in women (RR = 2.2; 95% CI: 1.5-3.2) and men (RR = 1.5; 95% CI: 1.2-2.2). However, lone atrial fibrillation (which occurred in 15 subjects) was not associated with a statistically significant increase in either cardiovascular events (RR = 1.5; 95% CI: 0.6-3.6) or mortality (RR = 1.8; 95% CI: 0.9-3.8). Atrial fibrillation is associated with an increased long-term risk of stroke, heart failure, and all-cause mortality, especially in women.