A Concept Analysis of Transitions of Care for Population Health

Background: Compelling evidence indicates that gaps in quality, safety, and experiences occur when patients encounter transitions across the care continuum. Differences in the organization of healthcare services as well as disparities in health across the globe, may have a unique impact on processes associated with transitions of care for client populations. Purpose: Increased attention to the concept of transitions of care has resulted in disparate meanings and lack of clarity about its nature. Therefore, the purpose of this manuscript is to address this knowledge gap by analyzing the concept of transitions of care at the population level. Methodology: To address the knowledge gap of what constitutes transitions of care at the population level, a concept analysis was done guided by the methodology of Walker and Avant. A comprehensive search of the literature yielded a small but relevant number of publications. Results: This analysis identified four defining attributes, together with antecedents and consequences of transitions of care at the macro-system level of healthcare. A synthesized definition of transitions of care was developed. Implications for Practice: This analysis provides conceptual clarity for the concept of transitions of care at the macro-system level of care. It can be used to guide the development of a middle-range theory to inform clinical practice and health policy

The matrix metalloproteinase inhibitor marimastat promotes neural progenitor cell differentiation into neurons by gelatinase-independent TIMP-2-dependent mechanisms.

Metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs), produced in the brain by cells of non-neural and neural origin, including neural progenitors (NPs), are emerging as regulators of nervous system development and adult brain functions. In the present study, we explored whether MMP-2, MMP-9, and TIMP-2, abundantly produced in the brain, modulate NP developmental properties. We found that treatment of NPs, isolated from the murine fetal cerebral cortex or adult subventricular zone, with the clinically tested broad-spectrum MMP inhibitor Marimastat profoundly affected the NP differentiation fate. Marimastat treatment allowed for an enrichment of our cultures in neuronal cells, inducing NPs to generate higher percentage of neurons and a lower percentage of astrocytes, possibly affecting NP commitment. Consistently with its proneurogenic effect, Marimastat early downregulated the expression of Notch target genes, such as Hes1 and Hes5. MMP-2 and MMP-9 profiling on proliferating and differentiating NPs revealed that MMP-9 was not expressed under these conditions, whereas MMP-2 increased in the medium as pro-MMP-2 (72 kDa) during differentiation; its active form (62 kDa) was not detectable by gel zymography. MMP-2 silencing or administration of recombinant active MMP-2 demonstrated that MMP-2 does not affect NP neuronal differentiation, nor it is involved in the Marimastat proneurogenic effect. We also found that TIMP-2 is expressed in NPs and increases during late differentiation, mainly as a consequence of astrocyte generation. Endogenous TIMP-2 did not modulate NP neurogenic potential; however, the proneurogenic action of Marimastat was mediated by TIMP-2, as demonstrated by silencing experiments. In conclusion, our data exclude a major involvement of MMP-2 and MMP-9 in the regulation of basal NP differentiation, but highlight the ability of TIMP-2 to act as key effector of the proneurogenic response to an inducing stimulus such as Marimastat