The action potential duration (APD) of isolated guinea pig papillary muscle is directly related to the medium glucose concentration regardless of the gas mixture with which it is in equilibrium. The APD can be maintained at control value for many hours by a glucose concentration of 50 mM in the complete absence of oxygen. Following reduction of the APD by incubation of the muscle in medium cont...

This study examined the nature of the undergraduate curricula for Auditory Processing Disorders (APD) for communication pathologists (speech-language therapists and audiologists) within the South African context. An exploratory descriptive survey design was utilised. The respondents (N=9) were the authoritative voices in the area of APD, i.e. academics based at training institutions involved in...

Monoclonal antibodies (mAbs) targeting the immune checkpoint anti-programmed cell death protein 1 (aPD-1) have demonstrated impressive benefits for the treatment of some cancers; however, these drugs are not always effective, and we still have a limited understanding of the mechanisms that contribute to their efficacy or lack thereof. We used in vivo imaging to uncover the fate and activity of ...

T-wave alternans, a powerful marker of arrhythmic events, results from alternation in action potential duration (APD). The underlying cellular mechanism of APD alternans is unknown but has been attributed to either intracellular calcium (Ca2+) cycling or membrane ionic currents, manifested by a steep slope of cellular APD restitution. To address these mechanisms, high-resolution optical mapping...

BACKGROUND T-wave alternans, which is associated with the genesis of cardiac fibrillation, has recently been related to discordant action potential duration (APD) alternans. However, the cellular electrophysiological mechanisms responsible for discordant alternans are poorly understood. METHODS AND RESULTS We simulated a 2D sheet of cardiac tissue using phase 1 of the Luo-Rudy cardiac action ...

As the serotonin transporter gene (SLC6A4 or 5-HTT) is a key regulator of central serotonergic activity, several association studies between Antisocial Personality Disorder (APD) and the SLC6A4 polymorphisms have been conducted in the last decade. In the present study, the role of both 5-HTTLPR and 5-HTTVNTR polymorphisms of the SLC6A4 gene in APD is investigated. A sample of 147 male inmates w...

Pediatric hearing evaluation based on pure tone audiometry does not always reflect how a child hears in everyday life. This practice is inappropriate when evaluating the difficulties children experiencing auditory processing disorder (APD) in school or on the playground. Despite the marked increase in research on pediatric APD, there remains limited access to proper evaluation worldwide. This p...

Using a new method for long-term recording of monophasic action potentials from the human heart, we studied in 17 patients the effects on ventricular action potential duration (APD) of three clinically pertinent cycle length perturbations: (1) single extrastimuli, (2) abrupt sustained rate acceleration and deceleration, and (3) different steady-state cycle lengths. Results were: (a) APD after s...

The aim of this study was to explore primary school teachers’ awareness and knowledge of (Central) Auditory Processing Disorder ((C)APD). Teachers’ awareness and knowledge are crucial for initial recognition and appropriate referral of children suspected of having (C)APD. When a child is diagnosed with (C)APD, teachers have a role in implementing and monitoring the effectiveness of intervention...

BACKGROUND Restitution kinetics and alternans of ventricular action potential duration (APD) have been shown to be important determinants of cardiac electrical stability. In this study, we tested the hypothesis that APD restitution and alternans properties differ between normal and diseased human ventricular myocardium. METHODS AND RESULTS Monophasic action potentials were recorded from the r...