Seasonal reproduction represents a naturally occurring example of functional plasticity in the adult brain since it reflects changes in neuroendocrine pathways controlling GnRH secretion and, in particular, the responsiveness of GnRH neurons to estradiol negative feedback. Structural plasticity within this neural circuitry may, in part, be responsible for seasonal switches in the negative feedback control of GnRH secretion that underlies annual reproductive transitions. In this paper, we review evidence for structural changes in the circuitry responsible for seasonal inhibition of GnRH secretion in sheep. These include changes in synaptic inputs onto GnRH neurons, as well as onto dopamine neurons in the A15 cell group, a nucleus that play a key role in estradiol negative feedback. We also present preliminary data suggesting a role for neurotrophins and neurotrophin receptors as an early mechanistic step in the plasticity that accompanies seasonal reproductive transitions in the sheep. Finally, we review recent evidence suggesting that kisspeptin cells of the arcuate nucleus constitute a critical intermediary in the control of seasonal reproduction. While a majority of the data for a role of neuronal plasticity in seasonal reproduction has come from the sheep model, the players and principles are likely to have relevance for reproduction in a wide variety of vertebrates, including humans, and in both health and disease.
To evaluate the significance of persistent negative T waves during severe ischemia, we prospectively studied 62 patients admitted for unstable angina without evidence of recent or ongoing myocardial infarction. A critical stenosis on the left anterior descending coronary artery (LAD), considered as the culprit lesion, was successfully treated by percutaneous transluminal coronary angioplasty (PTCA). The patients were divided into two groups according to the admission electrocardiogram: T NEG group (n =32) had persistent negative T waves, and the T POS group (n=30) had normal positive T waves on precordial leads. The two groups had similar baseline clinical, hemodynamic, and angiographic characteristics. All patients underwent a complete clinical and angiographic evaluation (coronary arteriography and left ventriculography) before undergoing PTCA and 8±3 months later. Left ventricular anterior wall motion was evaluated by the percent shortening of three areas (S1, S2, and S3) considered as LAD-related segments on left ventriculograms. Before PTCA, there was no significant difference in global ejection fraction between the two groups despite a significant depression in anterior mean percent area shortening in the T NEG compared with the T POS group (S1, 44 versus 54, p<0.01; S2, 39 versus 48, p<0.01; S3, 44 versus 50, NS). At repeated angiography, the anterior mean percent area shortening improved significantly in the T NEG group (S1, from 44 to 61,p<0.001; S2, from 39 to 58,p<0.001; S3, from 44 to 61,p<0.001). This resulted in a reduced end-systolic volume (from 41±14 to 31 + 13 ml/m2, p <0.01) and improved ejection fraction (from 61±8% to 69±10%, p
qualitative research, via a semi-structured interview with 10% of the 120 strong consultant body. A thematic analysis was undertaken. Results Thematic review showed doctors felt they lacked influence, that communication from senior management was poor and they lacked a feeling of belonging.We have encouraged senior medics to lead on a host of strategic clinical initiatives, pathways and QI projects.We have instigated a series of 'quick wins' from feedback gained thus far, to address doctors concerns and communicated these widely through a 'you said, we did' approach.Our repeat Pulse Check survey has shown improvement in medical engagement across all domains.
Phenomenon: Satellite campuses of medical schools in Canada introduce smaller communities to new medical learners. Non-physician health care professionals (NPHCPs) in regional hospitals may have had little prior exposure to learners. Lack of clarity regarding the role of the medical student is a barrier that hinders interprofessional collaboration. The purpose of this project was to examine the educational relationship between students and NPHCPs in regional hospitals. Approach: Surveys were distributed to NPHCPs of various disciplines at two community hospitals in Waterloo Region. A second survey was distributed to medical students attending a satellite medical campus of McMaster University. Findings: Surveys completed by 141 NPHCPs identified the following themes: frequent student interaction, no orientation to students, uncertainty of roles, willingness to teach, and barriers to teaching. Student surveys demonstrated frequent interactions, lack of familiarity of their role by NPHCPs at regional hospitals, desire to learn from NPHCPs, and specific teachable procedures. Insights: NPHCPs and medical students agree that interprofessional medical education can improve patient care, communication and the quality of education. While there is interest in involving NPHCPs in teaching, orienting NPHCPs to the roles of students in regional hospitals may improve relationships and allow informal teaching opportunities.
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