ABSTRACT
In the last two decades, the zebrafish has emerged as an important model species for heart regeneration studies. Various approaches to model loss of cardiac myocytes and myocardial infarction in the zebrafish have been devised, and have included resection, genetic ablation, and cryoinjury. However, to date, the response of the zebrafish ventricle to cautery injury has not been reported. Here, we describe a simple and reproducible method using cautery injury via a modified nichrome inoculating needle as a probe to model myocardial infarction in the zebrafish ventricle. Using light and electron microscopy, we show that cardiac cautery injury is attended by significant inflammatory cell infiltration, accumulation of collagen in the injured area, and the reconstitution of the ventricular myocardium. Additionally, we document the ablation of cardiac nerve fibers, and report that the re-innervation of the injured zebrafish ventricle is protracted, compared to other repair processes that accompany the regeneration of the cauterized ventricle. Taken together, our study demonstrates that cautery injury is a simple and effective means for generating necrotic tissue and eliciting a remodeling and regenerative response in the zebrafish heart. This approach may serve as an important tool in the methods toolbox for regeneration studies in the zebrafish.
ABSTRACT
AimTo explore, for the first time, whether a modified mindfulness-based cognitive therapy (MBCT) course has the potential to reduce stress and burnout among National Health Service (NHS) General Practitioners. BACKGROUND: There is a crisis of low morale among NHS GPs, with most describing their workload as 'unmanageable'. MBCT has been demonstrated to improve stress and burnout in other populations, but has not yet been evaluated in a cohort of NHS GPs. METHODS: NHS GPs in South East England (n=22) attended a modified version of the MBCT course approved by National Institute for Health and Care Excellence for prevention of depressive relapse. This comprised eight weekly 2-h sessions with homework (mindfulness practice) between sessions. Participants completed the Maslach Burnout Inventory (MBI) and Perceived Stress Scale (PSS) before (baseline) and then again one month (T2) and three months (T3) after attending the course. We also obtained qualitative data on participants' experiences of the course.FindingsCompliance with the intervention was very high. All GPs attended at least six sessions and all completed baseline questionnaires. At T2, data were obtained from 21 participants (95%); PSS scores were significantly lower than at baseline (P<0.001), as were MBI emotional exhaustion (P<0.001) and depersonalization scores (P=0.0421). At T3 we obtained data for 13 participants (59%); PSS scores and MBI emotional exhaustion scores were significantly lower (P<0.001; P=0.0024, respectively) and personal accomplishment scores were significantly higher (P<0.001) than at baseline. Participants reported that the course helped them to manage work pressures, feel more relaxed, enjoy their work and experience greater empathy and compassion (for self, colleagues and patients). Findings of this preliminary evaluation are promising. Further research is needed to evaluate this approach within a larger randomized-controlled trial.
