Biological and behavioral markers of pain following nerve injury in humans

The evolution of peripheral and central changes following a peripheral nerve injury imply the onset of afferent signals that affect the brain. Changes to inflammatory processes may contribute to peripheral and central alterations such as altered psychological state and are not well characterized in humans. We focused on four elements that change peripheral and central nervous systems following ankle injury in 24 adolescent patients and 12 age-sex matched controls. Findings include (a) Changes in tibial, fibular, and sciatic nerve divisions consistent with neurodegeneration; (b) Changes within the primary motor and somatosensory areas as well as higher order brain regions implicated in pain processing; (c) Increased expression of fear of pain and pain reporting; and (d) Significant changes in cytokine profiles relating to neuroinflammatory signaling pathways. Findings address how changes resulting from peripheral nerve injury may develop into chronic neuropathic pain through changes in the peripheral and central nervous system

Staged Left Ventricular Recruitment After Single-Ventricle Palliation in Patients With Borderline Left Heart Hypoplasia

ObjectivesThe goal of this study was to review results of a novel management strategy intended to rehabilitate the left heart (LH) in patients with LH hypoplasia who have undergone single-ventricle palliation (SVP).BackgroundManagement of patients with hypoplastic LH syndrome and borderline left ventricle (LV) involves 2 options: SVP or biventricular repair. We hypothesized that staged LV recruitment and biventricular conversion may be achieved after SVP by using a strategy consisting of relief of inflow and outflow tract obstructions, resection of endocardial fibroelastosis, and promotion of flow through the LV.MethodsPatients with hypoplastic LH and borderline LV who underwent traditional SVP (n = 34) or staged LV recruitment (n = 34) between 1995 and 2010 were retrospectively analyzed and compared with a control SVP group.ResultsMean initial z-scores for LH structures before stage 1 SVP were not significantly different between groups. Mortality occurred in 4 of 34 patients after LV recruitment and in 7 of 34 after traditional SVP. LH dimension z-scores increased significantly over time after LV recruitment, whereas they declined after traditional SVP, with significant interaction between stage of palliation and treatment group. Restriction of the atrial septum (conducted in 19 of 34 patients) was the only predictor of increase in left ventricular end-diastolic volume (p < 0.001). Native biventricular circulation was achieved in 12 patients after staged LV recruitment; all of these patients had restriction at the atrial septum.ConclusionsIn these patients with borderline LH disease who underwent SVP, it is possible to increase LH dimensions by using an LV recruitment strategy. In a subset of patients, this strategy allowed establishment of biventricular circulation

Evidence-based decision support for pediatric rheumatology reduces diagnostic errors.

BACKGROUND: The number of trained specialists world-wide is insufficient to serve all children with pediatric rheumatologic disorders, even in the countries with robust medical resources. We evaluated the potential of diagnostic decision support software (DDSS) to alleviate this shortage by assessing the ability of such software to improve the diagnostic accuracy of non-specialists. METHODS: Using vignettes of actual clinical cases, clinician testers generated a differential diagnosis before and after using diagnostic decision support software. The evaluation used the SimulConsult® DDSS tool, based on Bayesian pattern matching with temporal onset of each finding in each disease. The tool covered 5405 diseases (averaging 22 findings per disease). Rheumatology content in the database was developed using both primary references and textbooks. The frequency, timing, age of onset and age of disappearance of findings, as well as their incidence, treatability, and heritability were taken into account in order to guide diagnostic decision making. These capabilities allowed key information such as pertinent negatives and evolution over time to be used in the computations. Efficacy was measured by comparing whether the correct condition was included in the differential diagnosis generated by clinicians before using the software ( unaided ), versus after use of the DDSS ( aided ). RESULTS: The 26 clinicians demonstrated a significant reduction in diagnostic errors following introduction of the software, from 28% errors while unaided to 15% using decision support (p \u3c 0.0001). Improvement was greatest for emergency medicine physicians (p = 0.013) and clinicians in practice for less than 10 years (p = 0.012). This error reduction occurred despite the fact that testers employed an open book approach to generate their initial lists of potential diagnoses, spending an average of 8.6 min using printed and electronic sources of medical information before using the diagnostic software. CONCLUSIONS: These findings suggest that decision support can reduce diagnostic errors and improve use of relevant information by generalists. Such assistance could potentially help relieve the shortage of experts in pediatric rheumatology and similarly underserved specialties by improving generalists\u27 ability to evaluate and diagnose patients presenting with musculoskeletal complaints. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT02205086

Microstructural Alterations and Oligodendrocyte Dysmaturation in White Matter After Cardiopulmonary Bypass in a Juvenile Porcine Model.

BACKGROUND: Newly developed white matter (WM) injury is common after cardiopulmonary bypass (CPB) in severe/complex congenital heart disease. Fractional anisotropy (FA) allows measurement of macroscopic organization of WM pathology but has rarely been applied after CPB. The aims of our animal study were to define CPB-induced FA alterations and to determine correlations between these changes and cellular events after congenital heart disease surgery. METHODS AND RESULTS: Normal porcine WM development was first assessed between 3 and 7 weeks of age: 3-week-old piglets were randomly assigned to 1 of 3 CPB-induced insults. FA was analyzed in 31 WM structures. WM oligodendrocytes, astrocytes, and microglia were assessed immunohistologically. Normal porcine WM development resembles human WM development in early infancy. We found region-specific WM vulnerability to insults associated with CPB. FA changes after CPB were also insult dependent. Within various WM areas, WM within the frontal cortex was susceptible, suggesting that FA in the frontal cortex should be a biomarker for WM injury after CPB. FA increases occur parallel to cellular processes of WM maturation during normal development; however, they are altered following surgery. CPB-induced oligodendrocyte dysmaturation, astrogliosis, and microglial expansion affect these changes. FA enabled capturing CPB-induced cellular events 4 weeks postoperatively. Regions most resilient to CPB-induced FA reduction were those that maintained mature oligodendrocytes. CONCLUSIONS: Reducing alterations of oligodendrocyte development in the frontal cortex can be both a metric and a goal to improve neurodevelopmental impairment in the congenital heart disease population. Studies using this model can provide important data needed to better interpret human imaging studies

Influence of Bleeding Risk on Outcomes of Radial and Femoral Access for Percutaneous Coronary Intervention: An Analysis From the GLOBAL LEADERS Trial

Background: Radial artery access has been shown to reduce mortality and bleeding events, especially in patients with acute coronary syndromes. Despite this, interventional cardiologists experienced in femoral artery access still prefer that route for percutaneous coronary intervention. Little is known regarding the merits of each vascular access in patients stratified by their risk of bleeding. Methods: Patients from the Global Leaders trial were dichotomized into low or high risk of bleeding by the median of the PRECISE-DAPT score. Clinical outcomes were compared at 30 days. Results: In the overall population, there were no statistical differences between radial and femoral access in the rate of the primary end point, a composite of all-cause mortality, or new Q-wave myocardial infarction (MI) (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.42-1.15). Radial access was associated with a significantly lower rate of the secondary safety end point, Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding (HR 0.55, 95% CI 0.36-0.84). Compared by bleeding risk strata, in the high bleeding score population, the primary (HR 0.47, 95% CI 0.26-0.85; P = 0.012; Pinteraction = 0.019) and secondary safety (HR 0.57, 95% CI 0.35-0.95; P = 0.030; Pinteraction = 0.631) end points favoured radial access. In the low bleeding score population, however, the differences in the primary and secondary safety end points between radial and femoral artery access were no longer statistically significant. Conclusions: Our findings suggest that the outcomes of mortality or new Q-wave MI and BARC 3 or 5 bleeding favour radial access in patients with a high, but not those with a low, risk of bleeding. Because thisContexte : Il a et e d emontr e que l ’accès par l’artère radiale reduit la mortalite et les h emorragies, en particulier chez les patients presentant un syndrome coronarien aigu. Malgr e cela, les cardiologues interventionnels qui ont acquis de l’experience en matière d ’accès par l’artère femorale pr efèrent encore utiliser cette voie lorsqu ’ils doivent pratiquer une intervention coronarienne percutanee. On connaît mal l’interêt de chacune de ces techniques d ’accès vasculaire au regard du risque d’hemorragie. Methodologie : Les patients de l’essai GLOBAL LEADERS ont et e repartis en deux groupes, selon qu ’ils presentaient un risque d’hemorragie faible ou elev e d ’après le score PRECISE-DAPT median, puis les resultats cliniques ont et e compar es à 30 jours. Resultats : Dans l’ensemble de la population, aucune difference sta- tistiquement significative n’a et e observ ee entre l ’accès radial et l’accès femoral quant au critère d ’evaluation principal, compos e de la mortalite toutes causes confondues et d ’un nouvel infarctus du myocarde (IM) avec onde Q (rapport des risques instantanes [RRI] de 0,70; intervalle de confiance [IC] à 95 % : 0,42-1,15). L’accès radial a et e associe à un taux signi ficativement plus faible de survenue du critère secondaire d’evaluation de l ’innocuite, c ’est-à-dire une hemorragie de type 3 ou 5 selon la classification du BARC (Bleeding Academic Research Consortium) (RRI de 0,55; IC à 95 % : 0,36-0,84). Lorsqu’on compare les sujets en fonction du risque d’hemorragie, les critères d’evaluation de l ’innocuite principal (RRI de 0,47; IC à 95 % : 0,26- 0,85; p ¼ 0,012; pinteraction ¼ 0,019) et secondaire (RRI de 0,57; IC à 95 % : 0,35-0,95; p ¼ 0,030; pinteraction ¼ 0,631) sont favorables à l’accès radial au sein de la population presentant un risque d ’hemor- ragie elev e. Dans la population pr esentant un risque d ’hemorragie faible, les differences entre l ’accès radial et l’accès femoral quant aux critères d’evaluation de l ’innocuite principal et secondaire ne sont toutefois plus statistiquement significatives. Conclusions : Selon ces observations, les resultats concernant la mortalite ou la survenue d ’un nouvel IM avec onde Q et le risque d’hemorragie de type 3 ou 5 selon la classi fication du BARC indiquent que l’accès radial serait à privilegier lorsque le risque d ’hemorragie est elev e, mais pas lorsqu ’il est faible. Comme il ne s’agissait pas d’une analyse principale, il convient de considerer ces observations comme etant g en eratrices d ’hypothèses

Ephedrine Blocks Rat Sciatic Nerve In Vivo and Sodium Channels In Vitro

Background: The sympathomimetic drug ephedrine has been used intrathecally as the sole local anesthetic for labor and delivery. Because ephedrine may be a useful adjuvant to local anesthetics, the authors investigated the local anesthetic properties of ephedrine in a rat sciatic nerve block model and the underlying mechanism in cultured cells stably expressing N

A Dynamical Systems Model for Combinatorial Cancer Therapy Enhances Oncolytic Adenovirus Efficacy by MEK-Inhibition

Oncolytic adenoviruses, such as ONYX-015, have been tested in clinical trials for currently untreatable tumors, but have yet to demonstrate adequate therapeutic efficacy. The extent to which viruses infect targeted cells determines the efficacy of this approach but many tumors down-regulate the Coxsackievirus and Adenovirus Receptor (CAR), rendering them less susceptible to infection. Disrupting MAPK pathway signaling by pharmacological inhibition of MEK up-regulates CAR expression, offering possible enhanced adenovirus infection. MEK inhibition, however, interferes with adenovirus replication due to resulting G1-phase cell cycle arrest. Therefore, enhanced efficacy will depend on treatment protocols that productively balance these competing effects. Predictive understanding of how to attain and enhance therapeutic efficacy of combinatorial treatment is difficult since the effects of MEK inhibitors, in conjunction with adenovirus/cell interactions, are complex nonlinear dynamic processes. We investigated combinatorial treatment strategies using a mathematical model that predicts the impact of MEK inhibition on tumor cell proliferation, ONYX-015 infection, and oncolysis. Specifically, we fit a nonlinear differential equation system to dedicated experimental data and analyzed the resulting simulations for favorable treatment strategies. Simulations predicted enhanced combinatorial therapy when both treatments were applied simultaneously; we successfully validated these predictions in an ensuing explicit test study. Further analysis revealed that a CAR-independent mechanism may be responsible for amplified virus production and cell death. We conclude that integrated computational and experimental analysis of combinatorial therapy provides a useful means to identify treatment/infection protocols that yield clinically significant oncolysis. Enhanced oncolytic therapy has the potential to dramatically improve non-surgical cancer treatment, especially in locally advanced or metastatic cases where treatment options remain limited.National Institutes of Health (U.S.) (Grant R01 CA118545)National Institutes of Health (U.S.) (Grant R01 CA095701)National Institutes of Health (U.S.) (Grant U54 CA11297)National Institutes of Health (U.S.) (Grant U54-CA112967

In Silico Simulation of Corticosteroids Effect on an NFkB- Dependent Physicochemical Model of Systemic Inflammation

During the onset of an inflammatory response signaling pathways are activated for "translating" extracellular signals into intracellular responses converging to the activation of nuclear factor (NF)-kB, a central transcription factor in driving the inflammatory response. An inadequate control of its transcriptional activity is associated with the culmination of a hyper-inflammatory response making it a desired therapeutic target. Predicated upon the nature of the response, a systems level analysis might provide rational leads for the development of strategies that promote the resolution of the response.A physicochemical host response model is proposed to integrate biological information in the form of kinetic rules and signaling cascades with pharmacokinetic models of drug action for the modulation of the response. The unifying hypothesis is that the response is triggered by the activation of the NFkB signaling module and corticosteroids serve as a template for assessing anti-inflammatory strategies. The proposed in silico model is evaluated through its ability to predict and modulate uncontrolled responses. The pre-exposure of the system to hypercortisolemia, i.e. 6 hr before or simultaneously with the infectious challenge "reprograms" the dynamics of the host towards a balanced inflammatory response. However, if such an intervention occurs long before the inflammatory insult a symptomatic effect is observed instead of a protective relief while a steroid infusion after inducing inflammation requires much higher drug doses.We propose a reversed engineered inflammation model that seeks to describe how the system responds to a multitude of external signals. Timing of intervention and dosage regimes appears to be key determinants for the protective or symptomatic effect of exogenous corticosteroids. Such results lie in qualitative agreement with in vivo human studies exposed both to LPS and corticosteroids under various time intervals thus improving our understanding of how interacting modules generate a behavior