Registration of Zak ERA8 Soft White Spring Wheat Germplasm with Enhanced Response to ABA and Increased Seed Dormancy

Zak (ENHANCED RESPONSE to ABA8) (Reg. No. GP-966, PI 669443) is a unique line derived from soft white spring wheat ( L.) cultivar Zak that has increased seed dormancy but after-ripens within 10 to 16 wk. The goal in developing this germplasm was to use increased seed dormancy to improve tolerance to preharvest sprouting, a problem that can cause severe economic losses. This germplasm was developed by USDA-ARS, Pullman, WA, in collaboration with Washington State University. Zak was tested under experimental number 60.1.27.10. The mutation was generated by chemical mutagenesis followed by selection for the inability to germinate on abscisic acid (ABA) concentrations too low to inhibit wild-type Zak seed germination. The semidominant Zak line has been backcrossed twice to wild-type Zak. Following the first backcross, Zak showed similar morphological and grain quality traits to the original Zak cultivar

Radiofrequency Catheter Ablation for Pediatric Atrioventricular Nodal Reentrant Tachycardia: Impact of Age on Procedural Methods and Durable Success

Background Catheter‐based slow‐pathway modification (SPM) is the treatment of choice for symptomatic atrioventricular nodal reentrant tachycardia (AVNRT). We sought to investigate the interactions between patient age and procedural outcomes in pediatric patients undergoing catheter‐based SPM for AVNRT. Methods and Results A retrospective cohort study was performed, including consecutive patients undergoing acutely successful SPM for AVNRT from 2008 to 2017. Those with congenital heart disease, cardiomyopathy, and accessory pathways were excluded. Patients were stratified by age quartile at time of SPM. The primary outcome was AVNRT recurrence. A total of 512 patients underwent successful SPM for AVNRT. Age quartile 1 had 129 patients with a median age and weight of 8.9 years and 30.6 kg, respectively. Radiofrequency energy was used in 98% of cases. Follow‐up was available in 447 (87%) patients with a median duration of 0.8 years (interquartile range, 0.2–2.5 years). AVNRT recurred in 22 patients. Multivariable Cox proportional hazard modeling identified atypical AVNRT (hazard ratio [HR], 5.83; 95% CI, 2.01–16.96; P=0.001), dual atrioventricular nodal only (HR, 4.09; 95% CI, 1.39–12.02; P=0.011), total radiofrequency lesions (HR, 1.06 per lesion; 95% CI, 1.01–1.12; P=0.032), and the use of a long sheath (HR, 3.52; 95% CI, 1.23–10.03; P=0.010) as predictors of AVNRT recurrence; quartile 1 patients were not at higher risk of recurrence (HR, 0.45; 95% CI, 0.10–1.97; P=0.29). Complete heart block requiring permanent pacing occurred in one quartile 2 patient at 14.9 years of age. Conclusions Pediatric AVNRT can be treated with radiofrequency‐SPM with high procedural efficacy and minimal risk of complications, including heart block. Atypical AVNRT and dual atrioventricular nodal physiology without inducible tachycardia remain challenging substrates

Registration of Zak ERA8

Zak ERA8 (ENHANCED RESPONSE to ABA8) (Reg. No. GP-966, PI 669443) is a unique line derived from soft white spring wheat (Triticum aestivum L.) cultivar Zak that has increased seed dormancy but after-ripens within 10 to 16 wk. The goal in developing this germplasm was to use increased seed dormancy to improve tolerance to preharvest sprouting, a problem that can cause severe economic losses. This germplasm was developed by USDA–ARS, Pullman, WA, in collaboration with Washington State University. Zak ERA8was tested under experimental number 60.1.27.10. The ERA8mutation was generated by chemical mutagenesis followed by selection for the inability to germinate on abscisic acid (ABA) concentrations too low to inhibit wild-type Zak seed germination. The semidominant Zak ERA8 line has been backcrossed twice to wild-type Zak. Following the first backcross, Zak ERA8 showed similar morphological and grain quality traits to the original Zak cultivar