Novel role for integrin-linked kinase in modulation of coxsackievirus B3 replication and virus-induced cardiomyocyte injury

Viral myocarditis is a major cause of sudden cardiac death in children and young adults. Among viruses, coxsackievirus B3 (CVB3) is the most common agent for myocarditis. Recently, more consideration has been given to the role of signaling pathways in pathogenesis of enteroviral myocarditis, providing new platform for identifying a new potential therapeutic target for this, so far, incurable disease. Previously, we reported on the role of the protein kinase-B/Akt in CVB3 replication and virus-induced cell injury. Here, we report on regulation of virus-induced Akt activation by the integrin-linked kinase in infected mouse cardiomyocytes and HeLa cells. This study also presents the first observation that inhibition of ILK in CVB3-infected cells significantly improves the viability of infected cells, while blocking viral replication and virus release. Complementary experiments using a constitutively active form of Akt1 revealed that the observed protective effect of ILK inhibition is dependent on the associated downregulation of virus-induced Akt activation. To our knowledge, this is the first report of such beneficial effects of ILK inhibition in a viral infection model and conveys new insights in our efforts to characterize a novel therapeutic target for treatment of enteroviral myocarditis.     

Toll-like receptors differentially regulate CC and CXC chemokines in skeletal muscle via NF-kappaB and calcineurin

Immunologically active molecules such as cytokines and chemokines have been implicated in skeletal muscle weakness during sepsis as well as recovery from muscle injury. In sepsis, Toll-like receptors (TLRs) act as key sentinel molecules of the innate immune system. Here we determined skeletal muscle cell responses of two prototypical CC and CXC chemokine genes (monocyte chemoattractant protein 1 [MCP-1] and KC, respectively), to stimulation with specific TLR ligands. In addition, we examined whether NF-kappaB and calcineurin signaling are involved in these responses. Differentiated myotubes and intact whole muscles expressed TLR2, TLR4, TLR5, and TLR9. Stimulation with ligands for TLR2 (peptidoglycan) or TLR4 (LPS) elicited robust and equivalent levels of MCP-1 and KC mRNA expression, whereas stimulation of TLR5 (by flagellin) required gamma interferon priming to induce similar effects. Although both TLR2 and TLR4 ligands activated the NF-kappaB pathway, NF-kappaB reporter activity was approximately 20-fold greater after TLR4 stimulation than after TLR2 stimulation. Inhibitory effects of NF-kappaB blockade on TLR-mediated chemokine gene expression, by either pharmacological (pyrrolidine dithiocarbamate) or molecular (IKKbeta dominant-negative transfection) methods, were also more pronounced during TLR4 stimulation. In contrast, inhibitory effects on TLR-mediated chemokine expression of calcineurin blockade (by FK506) were greater for TLR2 than for TLR4 stimulation. MCP-1 and KC mRNA levels also demonstrated differential responses to NF-kappaB and calcineurin blockade during stimulation with specific TLR ligands. We conclude that skeletal muscle cells differentially utilize the NF-kappaB and calcineurin pathways in a TLR-specific manner to enable complex regulation of CC and CXC chemokine gene expression.     

Socioeconomic characteristics and comorbidities of diverticular disease in Sweden 1997–2012

Purpose

This study aimed to evaluate the association of socioeconomic status and comorbidities with uncomplicated and complicated diverticular disease (DD) in Sweden.

Methods

We identified all individuals aged ≥30 years in Sweden diagnosed with DD between 1997 and 2012 using the Swedish National Population and Housing Census and the Hospital Discharge Register. Data were analyzed by multivariable logistic regression, with individual-level characteristics as covariates.

Results

A total of 79,481 patients (median age 66 [range 30–86] years) were hospitalized for DD, 15,878 (20%) of whom for complicated DD. Admissions for both uncomplicated and complicated DD were more common in women (p < 0.001). A low education level was identified as a risk factor for uncomplicated (unadjusted hazard ratio [HR] 1.79, 95% confidence interval [CI] 1.75–1.82; adjusted HR 1.22, 95% CI 1.19–1.24) and complicated DD (unadjusted HR 1.84, 95% CI 1.77–1.92; adjusted HR 1.26, 95% CI 1.21–1.32). Patients with the lowest income had a lower risk of hospitalization for uncomplicated (adjusted HR 0.94, 95% CI 0.91–0.96) and complicated DD (adjusted HR 0.87, 95% CI 0.83–0.92) than those with the highest income. The correlation coefficient between income and education was 0.25. Diabetes and cardiovascular disease were identified as protective factors against uncomplicated DD (adjusted HR 0.68, 95% CI 0.66–0.69 and HR 0.79, 95% CI 0.74–0.84, respectively).

Conclusions

Patients with the lowest education level had an increased risk of hospitalization for DD. Further studies are needed to explore the association of diabetes and cardiovascular disease with uncomplicated DD.

     

Early innate and adaptive immune perturbations determine long-term severity of chronic virus and Mycobacterium tuberculosis coinfection

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Using email reminders to engage physicians in an Internet-based CME intervention

Background  

Engaging practicing physicians in educational strategies that reinforce guideline adoption and improve the quality of healthcare may be difficult. Push technologies such as email offer new opportunities to engage physicians in online educational reinforcing strategies. The objectives are to investigate 1) the effectiveness of email announcements in engaging recruited community-based primary care physicians in an online guideline reinforcement strategy designed to promote Chlamydia screening, 2) the characteristics of physicians who respond to email announcements, as well as 3) how quickly and when they respond to email announcements.     

Effects of treadmill running on spatial learning and memory in streptozotocin-induced diabetic rats

Previous studies have shown an association between diabetes mellitus and impairments in learning and memory. These deficits were partially reversed by the use of insulin. Due to the fact that exercise has positive effects on many physiological systems, including the central nervous system, the present study, evaluated the effects of treadmill running on spatial learning and memory in streptozotocin (STZ)-induced diabetic rats. The exercise program was treadmill running at 17 meters per minute (m/min) at 0° inclination for 40 minutes per day (min/day), 7 days/week, for 12 weeks. Experimental groups were: the control-rest, the control-exercise, the diabetes-rest and the diabetes-exercise. Spatial learning and memory was investigated by Morris water maze test in the rats after 12 weeks of diabetes induction and the exercise period. Our data showed that spatial learning and memory was significantly impaired in the diabetes-rest group with respect to the control-rest group. However, there were no differences between the other groups. The present results suggest that spatial learning and memory is affected under diabetic conditions and that treadmill running prevents these effects. The data correspond to the possibility that treadmill running is helpful in the prevention and alleviation of the cognitive decline in diabetes mellitus.     

Myocardial Perfusion SPECT Imaging Radiomic Features and Machine Learning Algorithms for Cardiac Contractile Pattern Recognition

A U-shaped contraction pattern was shown to be associated with a better Cardiac resynchronization therapy (CRT) response. The main goal of this study is to automatically recognize left ventricular contractile patterns using machine learning algorithms trained on conventional quantitative features (ConQuaFea) and radiomic features extracted from Gated single-photon emission computed tomography myocardial perfusion imaging (GSPECT MPI). Among 98 patients with standard resting GSPECT MPI included in this study, 29 received CRT therapy and 69 did not (also had CRT inclusion criteria but did not receive treatment yet at the time of data collection, or refused treatment). A total of 69 non-CRT patients were employed for training, and the 29 were employed for testing. The models were built utilizing features from three distinct feature sets (ConQuaFea, radiomics, and ConQuaFea + radiomics (combined)), which were chosen using Recursive feature elimination (RFE) feature selection (FS), and then trained using seven different machine learning (ML) classifiers. In addition, CRT outcome prediction was assessed by different treatment inclusion criteria as the study’s final phase. The MLP classifier had the highest performance among ConQuaFea models (AUC, SEN, SPE = 0.80, 0.85, 0.76). RF achieved the best performance in terms of AUC, SEN, and SPE with values of 0.65, 0.62, and 0.68, respectively, among radiomic models. GB and RF approaches achieved the best AUC, SEN, and SPE values of 0.78, 0.92, and 0.63 and 0.74, 0.93, and 0.56, respectively, among the combined models. A promising outcome was obtained when using radiomic and ConQuaFea from GSPECT MPI to detect left ventricular contractile patterns by machine learning.

     

Neutrophil and platelet activity and quantification following delayed tPA therapy in a rabbit model of thromboembolic stroke

Although there is considerable interest in the role of neutrophils and platelets in acute cerebral ischemiareperfusion, there are very little data related to the effect of systemic thrombolytic therapy on these blood elements. In the present study a rabbit model was used to examine the effects of cerebral ischemia, tissue-plasminogen activator therapy, or both on neutrophil and platelet peripheral counts and activity, the latter studied by stimulated neutrophil and platelet impedance aggregation and neutrophil oxygen-free radical chemiluminescence. New Zealand white rabbits (n=25) were randomized to receive either tissue-plasminogen activator (6.3 mg/kg IV; 20% bolus, remainder as a 2-hour infusion) or vehicle (0.9% saline) 3 hours following either autologous clot embolization or sham carotid artery isolation. Thus, four groups were examined: sham (n=4), tPA only (n=4), stroke only (n=8), and stroke plus tPA (n=9). Two hours after completion of thrombolytic therapy or vehicle infusion, the experiments were terminated, that is, 7 hours following autologous clot embolization or sham instrumentation. Blood was sampled from the thoracic aorta, and neutrophil and platelet peripheral counts and activity were determined prior to embolization and 0.5, 2.0, 4.0, and 7.0 hours following autologous clot embolization. No significant difference in platelet counts, either over time or between groups, was noted. In contrast to the platelet counts, the neutrophil count significantly increased over time, rising approximately 2.5-fold from baseline in all four groups (p<0.001). No significant increase in neutrophil accumulation (myeloperoxidase assay; 10⁷ PMNs/g tissue; mean ± SEM) was noted within infarcted regions of either the stroke (1.26±0.07; n=5) or stroke plus tissue-plasminogen activator (1.26±0.09; n=5) groups when compared to either viable brain regions within the ischemic hemisphere (1.29±0.03; n=4) or in sham controls (1.36±0.35; n=4). Neutrophil activity (aggregation, oxygen-free radical release) in both groups undergoing autologous clot embolization demonstrated a trend toward higher values when compared to the two sham-operated groups. Tissue-plasminogen activator administration did not significantly affect ex vivo neutrophil activity. In contrast, platelet aggregation was significantly reduced by the administration of tPA with (p=0.001) or without (p<0.01) autologous clot embolization. Thus, in the present rabbit model platelet but not neutrophil activity is modulated by the administration of tissue-plasminogen activator, while autologous clot embolization results in a trend toward acute neutrophil activation.     

No increased risk of early revision during the implementation phase of new cup designs

Background and purpose — In Sweden, less than 5% of patients who undergo total hip arthroplasty (THA) have revision. Younger patients have an increased risk of revision. New prosthetic designs are being introduced in order to improve outcomes further. We investigated whether the introductory phase of new cup designs would increase the revision rate.

Patients and methods — All THAs and first-time cup revisions performed from 1993 through 2011 were identified in the Swedish Hip Arthroplasty Register. The 15 types of cups used in more than 500 operations and inserted in more than 50 cases in each hospital (n = 52,903) were selected. All cups were given an order number, based on the order in which the cup had been inserted at each hospital. The influence of order number on the risk of revision was analyzed in a regression model, which was adjusted for potentially confounding demographic and surgical data. Revision within 2 years for all reasons (n = 940) was used as primary endpoint. Changes in the risk of revision based on the order number were analyzed using a spline.

Results — The order number of the cup had no influence on the risk of early revision (p ≥ 0.7). Categorizing the order number using cutoff values obtained from the splines did not result in any statistically significant changes in risk of revision (p ≥ 0.2).

Interpretation — We did not find any increased risk of early revision during the implementation phase of new cup designs. This finding is unexpected, and partly conflicts with data from other registries. The structured and stepwise introduction of new prosthesis designs, facilitated by the annual feedback from the Swedish Hip Arthroplasty Register, may partly explain this discrepancy.