Critical Care Recovery Center: a model of agile implementation in intensive care unit (ICU) survivors.

BACKGROUND: As many as 70% of intensive care unit (ICU) survivors suffer from long-term physical, cognitive, and psychological impairments known as post-intensive care syndrome (PICS). We describe how the first ICU survivor clinic in the United States, the Critical Care Recovery Center (CCRC), was designed to address PICS using the principles of Agile Implementation (AI). METHODS: The CCRC was designed using an eight-step process known as the AI Science Playbook. Patients who required mechanical ventilation or were delirious ≥48 hours during their ICU stay were enrolled in the CCRC. One hundred twenty subjects who completed baseline HABC-M CG assessments and had demographics collected were included in the analysis to identify baseline characteristics that correlated with higher HABC-M CG scores. A subset of patients and caregivers also participated in focus group interviews to describe their perceptions of PICS. RESULTS: Quantitative analyses showed that the cognitive impairment was a major concern of caregivers. Focus group data also confirmed that caregivers of ICU survivors (n = 8) were more likely to perceive cognitive and mental health symptoms than ICU survivors (n = 10). Caregivers also described a need for ongoing psychoeducation about PICS, particularly cognitive and mental health symptoms, and for ongoing support from other caregivers with similar experiences. CONCLUSIONS: Our study demonstrated how the AI Science Playbook was used to build the first ICU survivor clinic in the United States. Caregivers of ICU survivors continue to struggle with PICS, particularly cognitive impairment, months to years after discharge. Future studies will need to examine whether the CCRC model of care can be adapted to other complex patient populations seen by health-care professionals.

ROCK1 functions as a critical regulator of stress erythropoiesis and survival by regulating p53.

Erythropoiesis is a dynamic, multistep process whereby hematopoietic stem cells differentiate toward a progressively committed erythroid lineage through intermediate progenitors. Although several downstream signaling molecules have been identified that regulate steady-state erythropoiesis, the major regulators under conditions of stress remain poorly defined. Rho kinases (ROCKs) belong to a family of serine/threonine kinases. Using gene-targeted ROCK1-deficient mice, we show that lack of ROCK1 in phenylhydrazine-induced oxidative stress model results in enhanced recovery from hemolytic anemia as well as enhanced splenic stress erythropoiesis compared with control mice. Deficiency of ROCK1 also results in enhanced survival, whereas wild-type mice die rapidly in response to stress. Enhanced survivability of ROCK1-deficient mice is associated with reduced level of reactive oxygen species. BM transplantation studies revealed that enhanced stress erythropoiesis in ROCK1-deficient mice is stem cell autonomous. We show that ROCK1 binds to p53 and regulates its stability and expression. In the absence of ROCK1, p53 phosphorylation and expression is significantly reduced. Our findings reveal that ROCK1 functions as a physiologic regulator of p53 under conditions of erythroid stress. These findings are expected to offer new perspectives on stress erythropoiesis and may provide a potential therapeutic target in human disease characterized by anemia.

p85ß regulatory subunit of class IA PI3 kinase negatively regulates mast cell growth, maturation, and leukemogenesis.

We show that loss of p85α inhibits the growth and maturation of mast cells, whereas loss of p85ß enhances this process. Whereas restoring the expression of p85α in P85α(-/-) cells restores these functions, overexpression of p85ß has the opposite effect. Consistently, overexpression of p85ß in WT mast cells represses KIT-induced proliferation and IL-3-mediated maturation by inhibiting the expression of Microphthalmia transcription factor. Because p85α and p85ß differ in their N-terminal sequences, chimeric proteins consisting of amino or carboxy-terminal of p85α and/or p85ß do not rescue the growth defects of p85α(-/-) cells, suggesting cooperation between these domains for normal mast cell function. Loss of p85ß impaired ligand induced KIT receptor internalization and its overexpression enhanced this process, partly because of increased binding of c-Cbl to p85ß relative to p85α. In vivo, loss of p85ß resulted in increased mast cells, and bone marrow transplantation of cells overexpressing p85ß resulted in significant reduction in some tissue mast cells. Overexpression of p85ß suppressed the growth of oncogenic KIT-expressing cells in vitro and prolonged the survival of leukemic mice in vivo. Thus, p85α and p85ß differentially regulate SCF and oncogenic KIT-induced signals in myeloid lineage-derived mast cells.

Essential role for focal adhesion kinase in regulating stress hematopoiesis.

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that has been extensively studied in fibroblasts; however its function in hematopoiesis remains an enigma. FAK is thought to be expressed in myeloid and erythroid progenitors, and its expression is enhanced in response to cytokines such as granu-locyte macrophage colony-stimulating factor. Furthermore, bone marrow cells cultured in granulocyte macrophage colony-stimulating factor show active migration and chemoattractant-induced polarization, which correlates with FAK induction. While loss of FAK in mice results in embryonic lethality, we have deleted FAK in the adult bone marrow. We show an essential role for FAK in regulating hemolytic, myelotoxic, as well as acute inflammatory stress responses in vivo. In vitro, loss of FAK in erythroid and myeloid progenitor's results in impaired cytokine induced growth and survival, as well as defects in the activation and expression of antiapoptotic proteins caspase 3 and Bcl-x(L). Additionally, reduced migration and adhesion of myeloid cells on extracellular matrix proteins, as well as impaired activation of Rac GTPase is also observed in the absence of FAK. Our studies reveal an essential role for FAK in integrating growth/survival and adhesion based functions in myeloid and erythroid cells predominantly under conditions of stress.

ROCK1 functions as a suppressor of inflammatory cell migration by regulating PTEN phosphorylation and stability.

Rho kinases belong to a family of serine/threonine kinases whose role in recruitment and migration of inflammatory cells is poorly understood. We show that deficiency of ROCK1 results in increased recruitment and migration of macrophages and neutrophils in vitro and in vivo. Enhanced migration resulting from ROCK1 deficiency is observed despite normal expression of ROCK2 and a significant reduction in overall ROCK activity. ROCK1 directly binds PTEN in response to receptor activation and is essential for PTEN phosphorylation and stability. In the absence of ROCK1, PTEN phosphorylation, stability, and its activity are significantly impaired. Consequently, increased activation of downstream targets of PTEN, including PIP3, AKT, GSK-3beta, and cyclin D1, is observed. Our results reveal ROCK1 as a physiologic regulator of PTEN whose function is to repress excessive recruitment of macrophages and neutrophils during acute inflammation.