A role for neurotrophic factors, in particular brain-derived neurotrophic factor (BDNF), in modulating synaptic plasticity in the adult brain has been described in recent years by several laboratories. A great deal of emphasis has been placed on establishing its precise role in the expression of long-term potentiation (LTP) in the hippocampus. Here we attempt to address this question by investigating, ®rst, its release following induction of LTP in perforant path-granule cell synapses and, second, the signalling events which follow activation of the BDNF receptor, TrkB, in the presynaptic terminal. We report that BDNF release is increased from slices of dentate gyrus following tetanic stimulation of the perforant path and that TrkB activation is increased in synaptosomes prepared from tetanized dentate gyrus. These changes are accompanied by increased activation of one member of the family of mitogen-activated protein kinases, extracellular signal-regulated kinase (ERK) and the data indicate that these events play a role in modulating release of glutamate from perforant path-granule cell synapses, because the Trk inhibitor K252a and the ERK inhibitor, UO126, both inhibited the BDNF-induced enhancement of release. We propose that the increase in phosphorylation of the transcription factor cAMP response element binding protein and in protein synthesis might underlie the more persistent components of LTP in dentate gyrus.
In this study, the authors investigate changes in the presynaptic terminal of the dentate gyrus that accompany 2 types of hippocampal-dependent plasticity: spatial learning and long-term potentiation (LTP). Parallel changes occurred in the dentate gyrus of rats that had undergone training in the Morris water maze and had sustained LTP. In both cases, KCl-induced brain-derived neurotrophic factor release was increased, and this was accompanied by increased phosphorylation of TrkB and the mitogen-activated protein kinase, ERK. Glutamate release was also enhanced, and the data suggest that this may be a consequence of increased activation of TrkB and ERK. Because the data indicate that similar cellular modifications are shared by these 2 forms of plasticity, they provide circumstantial evidence that LTP satisfies some of the requirements of a memory-inducing cellular substrate.
Compassion and empathy are viewed as important by both nurses and patients. The positive emotions that nurses feel as a result of compassionate and empathic practice are known as compassion satisfaction, whilst the negative consequences are known as burnout and compassion fatigue. Empathy has two distinct components: emotional empathy, which involves feeling the emotions of another, and cognitive empathy, which relates to self-regulation of the emotion felt. The purpose of this literature review is to examine the relationship between burnout and empathy in the nursing literature. The results suggest that the relationship between these constructs is complex, and an ability to self-regulate emotions during empathic engagement may reduce the risk of burnout. The implications for nurses, health care organisations, educators and health care policy makers are discussed. This review provides insight into how adaptive empathic engagement may reduce the risk of burnout.
Healthcare delivery systems must ensure that early symptoms are addressed effectively in the presurgery period to improve quality of life and reduce adverse outcomes postsurgery.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.