The purpose of this study was to determine whether aged myocardium exhibits decreased responsiveness to adenosine A1 and A(2a) receptor activation. Studies were conducted in adult (4-6 months) and aged (24-26 months) Fischer 344 x Brown Norway hybrid (F344 x BN) rats. Effects of the adenosine A1/A(2a) agonist AMP579 were measured in isolated hearts and in rats submitted to in vivo regional myocardial ischemia. Aged isolated hearts exhibited lower spontaneous heart rates and higher coronary resistance, as well as normal A1- and A(2a)-mediated responses. There was no difference in control infarct size between adult and aged rats; however, AMP579 treatment resulted in a 50% greater infarct size reduction in aged rats (18 +/- 4% of risk area) compared to adult rats (37 +/- 3%). These findings suggest that adenosine A1 and A(2a) receptor-mediated effects are not diminished in normal aged myocardium, and that aged hearts exhibit increased adenosine agonist-induced infarct reduction.
Effective leadership in academic medicine requires a broad constellation of skills, experiences, and core values. The authors sought to describe and define these.
The authors conducted a web-based survey among 132 Chairs of North American departments of psychiatry.
Eighty-five Chairs (64%) responded to the survey, the majority of whom were first-time Chairs. Identified leadership attributes included strategic/visionary acumen, interpersonal communication skills, core administrative and academic/technical skills, motivational capacity, personal integrity, and altruism/tenacity.
The identified values are consistent with the leadership attributes that are described as necessary for success in the business community. Developing the required skill-set among faculty who aspire to become a departmental Chair is an important commitment for Deans and extant psychiatry Chairs.
The neuropathological findings of 32 progressive supranuclear palsy (PSP) cases over a period of 17 years were reviewed.
Of the 26 cases with adequate clinical data, 20 patients either presented with cognitive dysfunction or developed a cognitive impairment subsequently during the course of the disease. Co-existing changes of argyrophilic grains and corticobasal degeneration (CBD) were found in 28% and 32% of the cases respectively. Alzheimer-related pathology was found in 69% of cases but only 18.75% of cases fulfilled the consortium to establish a registry for Alzheimer's disease (CERAD) criteria for either definite or probable Alzheimer's disease. Lewy bodies were noted in four cases (12.5%), all in the subcortical regions. Only seven cases of PSP showed no pathological evidence of other co-existing neurodegenerative diseases. The severity of the cerebrovascular pathology in this cohort was insufficient to explain any clinical symptomatology.
As in previous studies, this study has demonstrated the frequent co-existence of pathological changes usually noted in other neurodegenerative diseases in PSP. Whether these co-existing pathological changes contribute to the cognitive impairment in PSP remains uncertain.