Current Aging Science (v.9, #2)
Methods: Through a review of published data, the cellular aging programs of both single cell and multicellular organisms are described. Since all organisms live in communities (ecosystems) of diverse species, the role of multi-level selection is discussed within this context and a proposal is advanced that aging represents an adaptive phenotype.Results: Single cell organisms evolved an aging phenotype in which the primary feature was replicative arrest prior to cell death. The evolution of multicellularity represented the emergence of a new level of biological organization. Multicellularity required cell-cell cooperation as well as a division of labor. In simple multicellular organisms aging was rooted in an age-related decline in stem cell function (renewal and differentiation). In complex multicellular organisms cellular aging/ death programs (senescence, autophagy, apoptosis) were used as a form of cell “altruistic” suicide carried out for the benefit of the whole organism (morphogenesis, tissue repair and maintenance). Organisms do not live in isolation. Species occupy ecological niches and communities of diverse species comprise an ecosystem. Ecosystems are highly regulated and structured biological organizations. The effective functioning and productivity of an ecosystem is determined by its biological diversity and relative species densities. Multilevel selection acts to balance optimal functioning of both the whole ecosystem and its compositional species/organisms.
Conclusions: Organismal aging and death programs are adaptive; these programs provide a mechanism for regulating species population densities within the constraints imposed by the ecosystem organization. A unique feature of humans has been the development of a second inheritance system, culture. Through cultural practices, humans have expanded our ecological niche to be global in size. Our technology enriched urban ecosystem is very different from natural ecosystems. Our future evolution, including aging and lifespan, will be determined by our unique urban ecosystem through geneculture co-evolution.
Objective: The goal of the present experiment was to test whether this beneficial effect of distracter exposure was observed in aged rats.
Method: Male FBNF hybrid rats (n=20) trained in a two-lever visual sustained attention task that required discrimination of brief illumination of a centrally located panel light compared with trials when the light was not illuminated. At age 20 months, half of the animals received a flashing houselight distracter for the remaining testing sessions and the other animals did not. After 20 sessions, new task trials were interspersed within the sessions, when the rats received water access for pressing the lever under the left or right panel light after that light was illuminated.
Results: When 70% of the trials in a session were the new discrimination task, the distracter-exposed animals had higher accuracy in detecting the shortest signal in the remaining attention task trials compared with rats not exposed to the distracter.
Conclusion: The present results suggest that aged animals' learning can benefit from overcoming distracter exposure, although not to the same extent as younger animals.
Objective: To summarise for individuals ?65 the rates of Potentially Inappropriate Medications (PIMs) identified by application of STOPP, and Potential Prescribing Omissions (PPOs) by START criteria.
Methods: Search: Databases were searched 1980 to 1 December 2015. For Medline the search yielded 3,691 systematic reviews or meta-analyses and 301 when limited to 65 years and over. STOPP.mp yielded 180 citations, START.mp 109,132 and 105 when limited to both. For Embase the search yielded 24,681 systematic reviews or meta-analyses, and 881 when limited to 65+ years. STOPP.mp yielded 427 citations and START.mp 147,322, and 327 when limited to both.
Results: Search: identified 28 studies with data and plus a systematic review using STOPP/START criteria. For community dwelling-individuals for national outpatient databases (n=1,528,785) PIMs weighted average was 31%, PPOs 47%. For small community studies (n=2,228) PIMs weighted average was 26%, PPOs 24%. For hospitalised patients (n=4,237) PIMs weighted average was 47%, PPOs 50%. For nursing home patients PIMs weighted average (n=1,539 patients) was 59%, PPOs (n=463 residents) 49%. Principal PIMs were benzodiazepines, proton pump inhibitors, NSAIDs, aspirin, and duplicate medications. Principal PPOs were omissions of medications for cardiovascular diseases, hypertension, osteoporosis, diabetes and hyperlipidemia.
Conclusions: Rates of PIMs and PPOs are high. Criteria are currently based on expert consensus. Next steps are to link criteria to the best internationally-accepted evidence-based systematic reviews/guidelines and conduct RCTs to test whether application of the criteria leads to lower rates of medication errors and hospital admissions.