An Evaluation of Mandatory Communicable Disease Reporting in North Carolina

The current communicable disease surveillance system in the United States largely relies on reporting of communicable diseases and conditions by both physicians and laboratories. Incomplete or inaccurate reporting of these diseases impairs the estimation of incidence rates from surveillance systems as well as hinders the implementation and evaluation of public health control measures. The extent of incomplete reporting has not been quantified for a large geographic area over time or for more than a few diseases. Therefore, the completeness of communicable disease reporting was studied using a retrospective cohort study at 8 large healthcare systems in North Carolina (NC) spanning a ten-year time period. The NC Department of Health and Human Services (NC DHHS) communicable disease surveillance system is based on mandatory reporting of more than 60 diseases and conditions and is a passive surveillance system. Diagnostic codes from healthcare system billing records were used to ascertain the eligible cases to be reported to the communicable disease surveillance system, and a unique identifier was used to match these eligible patients to the case-patients who were reported to the NC DHHS surveillance system. In addition, a validation study was also conducted to estimate positive predictive values of the diagnostic codes for communicable disease case ascertainment because these codes are widely used for both public health surveillance and research. Quantification of communicable disease reporting completeness is critical to understanding the impact on two public health surveillance system goals, that is, disease incidence rate estimation and public health initiation of disease transmission control measures. In addition, these analyses may guide the development of local, state and national strategies for improvement of disease reporting and surveillance

Lipoprotein profile in older patients with vascular dementia and Alzheimer's disease

BACKGROUND: Some alterations of the lipoprotein profile have been associated with cerebrovascular disease. Recently, it has been suggested that cerebrovascular disease might play a role in the pathogenesis of both vascular dementia (VD) and Alzheimer's disease (AD). Nevertheless, the possible association of dyslipidemias with VD or AD is still a controversial issue. METHODS: We investigated the lipoprotein profile in 100 older patients with vascular dementia (VD; n°: 60) or Late Onset Alzheimer's Disease (LOAD; n°: 40). The patients were compared with 54 community dwelling non-demented older controls. RESULTS: After adjustment for functional status, blood sedimentation rate, and serum albumin levels, no differences in lipoprotein profile emerged between the three groups, with the exception of HDL-C that was lower in VD compared with controls. Low HDL-C (< 45 mg/dL) was associated with VD (O.R.: 6.52, C.I. 95%: 1.42–30.70 vs controls, and 4.31, C.I. 95%: 0.93–19.82 vs LOAD), after multivariate adjustment. No differences in plasma lipid levels emerged between the three groups after stratification for apo E4 genotype. CONCLUSIONS: In this cross-sectional study low HDL-C levels are associated with VD, but not with LOAD, in a sample of older subjects

Staring, a Novel E3 Ubiquitin-Protein Ligase That Targets Syntaxin 1 for Degradation

Syntaxin 1 is an essential component of the neurotransmitter release machinery, and regulation of syntaxin 1 expression levels is thought to contribute to the mechanism underlying learning and memory. However, the molecular events that control the degradation of syntaxin 1 remain undefined. Here we report the identification and characterization of a novel RING finger protein, Staring, that interacts with syntaxin 1. Staring is expressed throughout the brain, where it exists in both cytosolic and membrane-associated pools. Staring binds and recruits the brain-enriched E2 ubiquitin-conjugating enzyme UbcH8 to syntaxin 1 and facilitates the ubiquitination and proteasome-dependent degradation of syntaxin 1. These findings suggest that Staring is a novel E3 ubiquitin-protein ligase that targets syntaxin 1 for degradation by the ubiquitin-proteasome pathway

Transcatheter versus surgical aortic valve replacement in intermediate risk patients: a meta-analysis

BACKGROUND: Transcatheter aortic valve replacement (TAVR) has been approved in patients with high or prohibited surgical risk for surgery for treatment of severe symptomatic aortic stenosis. Prospective studies examining the benefits of TAVR in intermediate risk patients are ongoing. Other smaller studies including lower risk patients have been conducted, but further meta-analysis of these studies is required to draw more broad comparisons. METHODS: A Medline search was conducted using standard methodology to search for clinical trials and observational studies including intermediate risk patients. We limited our meta-analysis to studies matching patient populations by propensity scores or randomization and examined clinical outcomes between TAVR and surgical aortic valve replacement (SAVR). RESULTS: Analysis of the TAVR and SAVR cohorts revealed no significant differences in the outcomes of 30-day [OR (95% CI): 0.85 (0.57, 1.26)] or 1-year mortality [OR (95% CI): 0.96 (0.75, 1.23)]. A trend towards benefit with TAVR was noted in terms of neurological events and myocardial infarction (MI) without statistical significance. A statistically significant decrease in risk of post-procedural acute renal failure in the TAVR group [OR (95% CI): 0.52 (0.27, 0.99)] was observed, but so was a significantly higher rate of pacemaker implantations for the TAVR group [OR (95% CI): 6.51 (3.23, 13.12)]. CONCLUSIONS: We conclude that in intermediate risk patients undergoing aortic valve replacement, the risk of mortality, neurological outcomes, and MI do not appear to be significantly different between TAVR and SAVR. However, there appears to be a significant reduction in risk of acute renal failure at the expense of an increased risk of requiring a permanent pacemaker in low and intermediate risk patients undergoing TAVR compared to SAVR

A Model of Fluid-Structure and Biochemical Interactions for Applications to Subclinical Leaflet Thrombosis

Subclinical leaflet thrombosis (SLT) is a potentially serious complication of aortic valve replacement with a bioprosthetic valve in which blood clots form on the replacement valve. SLT is associated with increased risk of transient ischemic attacks and strokes and can progress to clinical leaflet thrombosis. SLT following aortic valve replacement also may be related to subsequent structural valve deterioration, which can impair the durability of the valve replacement. Because of the difficulty in clinical imaging of SLT, models are needed to determine the mechanisms of SLT and could eventually predict which patients will develop SLT. To this end, we develop methods to simulate leaflet thrombosis that combine fluid-structure interaction and a simplified thrombosis model that allows for deposition along the moving leaflets. Additionally, this model can be adapted to model deposition or absorption along other moving boundaries. We present convergence results and quantify the model's ability to realize changes in valve opening and pressures. These new approaches are an important advancement in our tools for modeling thrombosis in which they incorporate both adhesion to the surface of the moving leaflets and feedback to the fluid-structure interaction.Comment: 29 pages, 11 figure

Simulating Cardiac Fluid Dynamics in the Human Heart

Cardiac fluid dynamics fundamentally involves interactions between complex blood flows and the structural deformations of the muscular heart walls and the thin, flexible valve leaflets. There has been longstanding scientific, engineering, and medical interest in creating mathematical models of the heart that capture, explain, and predict these fluid-structure interactions. However, existing computational models that account for interactions among the blood, the actively contracting myocardium, and the cardiac valves are limited in their abilities to predict valve performance, resolve fine-scale flow features, or use realistic descriptions of tissue biomechanics. Here we introduce and benchmark a comprehensive mathematical model of cardiac fluid dynamics in the human heart. A unique feature of our model is that it incorporates biomechanically detailed descriptions of all major cardiac structures that are calibrated using tensile tests of human tissue specimens to reflect the heart's microstructure. Further, it is the first fluid-structure interaction model of the heart that provides anatomically and physiologically detailed representations of all four cardiac valves. We demonstrate that this integrative model generates physiologic dynamics, including realistic pressure-volume loops that automatically capture isovolumetric contraction and relaxation, and predicts fine-scale flow features. None of these outputs are prescribed; instead, they emerge from interactions within our comprehensive description of cardiac physiology. Such models can serve as tools for predicting the impacts of medical devices or clinical interventions. They also can serve as platforms for mechanistic studies of cardiac pathophysiology and dysfunction, including congenital defects, cardiomyopathies, and heart failure, that are difficult or impossible to perform in patients

SNIP, a Novel SNAP-25-interacting Protein Implicated in Regulated Exocytosis

Synaptosome-associated protein of 25 kDa (SNAP-25) is a presynaptic membrane protein that has been clearly implicated in membrane fusion in both developing and mature neurons, although its mechanisms of action are unclear. We have now identified a novel SNAP-25-interacting protein named SNIP. SNIP is a hydrophilic, 145-kDa protein that comprises two predicted coiled-coil domains, two highly charged regions, and two proline-rich domains with multiple PPXY and PXXP motifs. SNIP is selectively expressed in brain where it co-distributes with SNAP-25 in most brain regions. Biochemical studies have revealed that SNIP is tightly associated with the brain cytoskeleton. Subcellular fractionation and immunofluorescence localization studies have demonstrated that SNIP co-localizes with SNAP-25 as well as the cortical actin cytoskeleton, suggesting that SNIP serves as a linker protein connecting SNAP-25 to the submembranous cytoskeleton. By using deletion analysis, we have mapped the binding domains of SNIP and SNAP-25, and we have demonstrated that the SNIP-SNAP-25 association is mediated via coiled-coil interactions. Moreover, we have shown that overexpression of SNIP or its SNAP-25-interacting domain inhibits Ca(2+)-dependent exocytosis from PC12 cells. These results indicate that SNIP is involved in regulation of neurosecretion, perhaps via its interaction with SNAP-25 and the cytoskeleton

The medically managed patient with severe symptomatic aortic stenosis in the TAVR era: Patient characteristics, reasons for medical management, and quality of shared decision making at heart valve treatment centers

Background Little is known about patients with severe symptomatic aortic stenosis (AS) who receive medical management despite evaluation at a heart valve treatment center. Objective We identified patient characteristics associated with medical management, physician-reported reasons for selecting medical management, and patients’ perceptions of their involvement and satisfaction with treatment selection. Methods and results Of 454 patients evaluated for AS at 9 established heart valve treatment centers from December 12, 2013 to August 19, 2014, we included 407 with severe symptomatic AS. Information was collected using medical record review and survey of patients and treating physicians. Of 407 patients, 212 received transcatheter aortic valve replacement (TAVR), 124 received surgical aortic valve replacement (SAVR), and 71 received medical management (no SAVR/TAVR). Thirty-day predicted mortality was higher in patients receiving TAVR (8.7%) or medical management (9.8%) compared with SAVR (3.4%) (P<0.001). Physician-reported reasons for medical management included patient preference (31.0%), medical futility (19.7%), inoperability/anatomic infeasibility (11.3%), and inadequate vascular access (8.5%). Compared with patients receiving AVR, medically managed patients were less likely to report that they received enough information about the pros and cons of treatment options (P = 0.03), that their physicians involved them in treatment decisions (P<0.001), and that final decisions were the right ones (P<0.001). Conclusions Patient preference was the most common physician-reported reason for selecting non-invasive AS management, yet patients not undergoing AVR after valve center evaluation reported being less likely to receive sufficient education about treatment options and more likely to feel uncertain about final treatment decisions. Greater attention to shared decision making may improve the experience of care for this vulnerable group of patients