Interest of the MGAP score on in-hospital trauma patients: Comparison with TRISS, ISS and NISS scores.

Trauma scoring systems were created to predict mortality and enhance triage capabilities. However, efficacy of scoring systems to predict mortality and accuracy of originally reported severity thresholds remains uncertain. A single-center, retrospective study was conducted at University of Virginia (UVA), an American College of Surgeons verified Level I trauma center. We compared four scoring systems: MGAP (Mechanism, Glasgow Coma Scale, Age, and arterial pressure), Injury Severity Score (ISS), New Injury Severity Score (NISS), and Trauma Related Injury Severity Score (TRISS) to predict in-hospital mortality and disposition from the emergency department to higher acuity level of care including mortality (i.e. operating room, intensive care unit, morgue) versus standard floor admission using area under the curve (AUC) for receiver operating characteristic analysis. Second, we examined sensitivity of these scores at standard thresholds to determine if adjustments were needed to minimize under-triage (sensitivity ≥95%). TRISS was the best predictor of mortality in a cohort of n = 16,265 with AUC of 0.920 (95% CI: 0.911-0.929, p<0.0001), followed by MGAP with AUC of 0.900 (95% CI: 0.889-0.911, p<0.0001), and finally ISS and NISS (0.830 (95% CI: 0.814-0.847) and 0.827 (95% CI: 0.809-0.844) respectively). NISS was the best predictor of high acuity disposition with an AUC of 0.729 (95% CI: 0.721-0.736, p<0.0001), followed by ISS with AUC of 0.714 (95% CI: 0.707-0.722, p<0.0001), and finally TRISS and MGAP (0.673 (95% CI: 0.665-0.682) and 0.613 (95% CI: 0.604-0.621) respectively (p<0.0001). At historic thresholds, no scoring system displayed adequate sensitivity to predict mortality, with values ranging from 73% for ISS to 80% for NISS. In conclusion, in the reported study cohort, TRISS was the best predictor of mortality while NISS was the best predictor of high acuity disposition. We also stress updating scoring system thresholds to achieve ideal sensitivity, and investigating how scoring systems derived to predict mortality perform when predicting indicators of morbidity such as disposition from the emergency department.

Autoantibodies to red blood cell surface Glycophorin A impact the activation poise of circulating leukocytes.

BACKGROUND: Both M and N alleles encode antigens on Glycophorin A (GPA), a red blood cell (RBC) surface sialoglycoprotein. Interaction between RBC GPA and leukocyte surface lectins may downregulate their activation. The current study investigates if RBC autoantibodies against GPA, such as auto-anti-M/N, prime an activated phenotype in peripheral blood leukocytes. METHODS: Leukocyte activation was assessed in whole blood from patients with auto-anti-GPA (anti-M/N) and compared to those with allo-anti-M/N and healthy subjects. Control samples from healthy subjects with no antibodies incubated in vitro with either anti-GPA or anti-Rh were analyzed for neutrophil and monocyte surface activation marker expression, reactive oxygen species (ROS) content, and formation of aggregates with RBCs. Samples incubated with an IgG1 isotype antibody served as controls. RESULTS: Ex vivo, neutrophil CD66b and monocyte CD63 surface expression was increased in patients with auto-anti-M/N compared to those with allo anti-M/N (p = .1757; p = .0698) and to healthy subjects (p = .0186; p = .013). In vitro, neutrophil CD66b and monocyte CD63 surface expression was increased following incubation with anti-GPA compared to anti-Rh (p = .0003; p = .0328) and isotype control (p = .000; p = .0062). Intracellular ROS content increased in both neutrophils and monocytes incubated with anti-GPA compared to anti-Rh (p = .0012; p = .0693) and isotype control (p = .001; p = .0021). Percentage of neutrophil-RBC aggregates was decreased when incubated with anti-GPA compared to isotype control (p < .01). CONCLUSIONS: Neutrophils and monocytes in peripheral blood exposed to an antibody directed against GPA on RBC surfaces, such as M or N antigens, may be primed towards an activated phenotype.

Dendritic remodeling of D1 neurons by RhoA/Rho-kinase mediates depression-like behavior.

Depression alters the structure and function of brain reward circuitry. Preclinical evidence suggests that medium spiny neurons (MSNs) in the nucleus accumbens (NAc) undergo structural plasticity; however, the molecular mechanism and behavioral significance is poorly understood. Here we report that atrophy of D1, but not D2 receptor containing MSNs is strongly associated with social avoidance in mice subject to social defeat stress. D1-MSN atrophy is caused by cell-type specific upregulation of the GTPase RhoA and its effector Rho-kinase. Pharmacologic and genetic reduction of activated RhoA prevents depressive outcomes to stress by preventing loss of D1-MSN dendritic arbor. Pharmacologic and genetic promotion of activated RhoA enhances depressive outcomes by reducing D1-MSN dendritic arbor and is sufficient to promote depressive-like behaviors in the absence of stress. Chronic treatment with Rho-kinase inhibitor Y-27632 after chronic social defeat stress reverses depression-like behaviors by restoring D1-MSN dendritic complexity. Taken together, our data indicate functional roles for RhoA and Rho-kinase in mediating depression-like behaviors via dendritic remodeling of NAc D1-MSNs and may prove a useful target for new depression therapeutics.

Fabrication of Tobacco Mosaic Virus-Like Nanorods for Peptide Display.

Virus-like particles (VLPs) are genome-free protein shells assembled from virus coat proteins (CPs). The uniform and nanoscale structure of VLPs combined with their noninfectious nature have made them ideal candidates for the display of functional peptides. While the vast majority of VLPs are derived from spherical viruses, tobacco mosaic virus (TMV) produces a rod-shaped particle with a hollow central channel. However, under physiological conditions the TMV CP forms only disk-shaped macromolecules. Here, we describe the design, construction, purification, and processing of rod-shaped TMV-VLPs using a simple bacterial expression system. The robust nature of this system allows for the display of functional peptides and molecules on the outer surface of this novel VLP.