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BACKGROUND: Angiopoietin-1 and 2 (Ang1, Ang2) are important mediators of angiogenesis. Angiopoietin levels are perturbed in cardiovascular disease, but it is unclear whether angiopoietin signaling is causative, an adaptive response, or merely epiphenomenon of disease activity. METHODS AND RESULTS: In a cohort free of cardiovascular disease at baseline (MESA), relationships between angiopoietins, cardiac morphology, and subsequent incidence of heart failure or cardiovascular death were evaluated. In cohorts with pulmonary arterial hypertension (PAH) or left heart disease (LHD), associations between angiopoietins, invasive hemodynamics, and adverse clinical outcomes were evaluated. In MESA, Ang2 was associated with a higher incidence of heart failure or cardiovascular death (HR 1.21 per standard deviation, P

Previous benchtop studies have shown that robotic bulldog clamps provide incomplete vascular control of a Penrose drain. We determined the efficacy of robotic and laparoscopic bulldog clamps to ensure hemostasis on the human renal artery. The effect of clamp position on vascular control was also examined.Fresh human cadaveric renal arteries were used to determine the leak point pressure of 7 bulldog clamps from a total of 3 manufacturers. Five trials were performed per clamp at 4 locations, including the fulcrum, proximal, middle and distal positions. Comparison was done using the Kruskal-Wallis test with p0.05 considered significant.None of the bulldog clamps leaked at a pressure less than 215 mm Hg when applied at the proximal, middle or distal position. In general leak point pressure decreased as the artery was positioned more distal along the clamp. The exception was when the vessel was placed at the fulcrum position. At that position 80% to 100% of trials with the Klein laparoscopic, 100% with the Klein robotic (Klein Robotic, San Antonio, Texas) and 60% to 80% with the Scanlan robotic (Scanlan International, Saint Paul, Minnesota) clamp leaked at pressure below 215 mm Hg.Each vascular clamp adequately occluded flow at physiological pressure when placed at the proximal, middle or distal position. Furthermore, these results demonstrate that there is leakage at physiological pressure when the artery is placed at the fulcrum of certain clamp types. These results suggest that applying a bulldog clamp at the fulcrum could potentially lead to inadequate vessel occlusion and intraoperative bleeding.

Given the potential importance of marginal artery localization in automated registration in computed tomography colonography (CTC), we have devised a semi-automated method of marginal vessel detection employing sequential Monte Carlo tracking (also known as particle filtering tracking) by multiple cue fusion based on intensity, vesselness, organ detection, and minimum spanning tree information for poorly enhanced vessel segments. We then employed a random forest algorithm for intelligent cue fusion and decision making which achieved high sensitivity and robustness. After applying a vessel pruning procedure to the tracking results, we achieved statistically significantly improved precision compared to a baseline Hessian detection method (2.7% versus 75.2%, p < 0.001). This method also showed statistically significantly improved recall rate compared to a 2-cue baseline method using fewer vessel cues (30.7% versus 67.7%, p < 0.001). These results demonstrate that marginal artery localization on CTC is feasible by combining a discriminative classifier (i.e., random forest) with a sequential Monte Carlo tracking mechanism. In so doing, we present the effective application of an anatomical probability map to vessel pruning as well as a supplementary spatial coordinate system for colonic segmentation and registration when this task has been confounded by colon lumen collapse. Published by Elsevier B.V.

To investigate the effect of laser fiber stripping on stone fragmentation and laser fiber power output.In a benchtop simulation of laser lithotripsy, 20 BegoStone phantoms were positioned within a ureteral model and irradiated for 10 minutes at 8 Hz and 0.8 J. A freshly cleaved 365 μm laser fiber was used for all trials, with half of the fibers also undergoing stripping. Power output was measured at 1-minute intervals, beginning with an initial prelithotripsy recording at 0 minutes. Fiber tips were imaged with scanning electron microscopy. In a single-blinded manner, final masses of residual stone fragments were measured and used to quantify stone breakdown. Independent-sample Mann-Whitney U tests were performed with significance set at p 0.05, comparing stripped and unstripped fiber tips with respect to power output and fraction of stone fragmentation.Mean power output after 1 minute of lasing was significantly greater in unstripped laser fibers (p = 0.015), while fibers, whether stripped or not, demonstrated no significant output differences prelithotripsy or at any time from 2 to 10 minutes. However, stripped laser fibers achieved significantly increased stone breakdown compared to unstripped fibers (p = 0.004), fragmenting 63 mg (25%) more of the initial stone mass per trial.Although unstripped laser fibers provided superior power output at 1 minute, output at all other time points was similar between stripped and unstripped fibers. However, despite similar optical output, stripped laser fibers achieved greater stone fragmentation, possibly due to improved contact between stone and fiber tip.

Various cleave techniques have recently been shown to significantly impact initial laser fiber power output during holmium laser lithotripsy. The impact of cleave technique on long-term power output has not been well characterized. The purpose of this study was to determine the effect of laser cleave technique on power output over time.In this randomized single-blinded study, five cleave techniques were tested on two holmium laser fiber diameters (200, 365 μm) over 15 minutes of laser lithotripsy with calcium oxalate monohydrate stones. Comparisons between cleave techniques and fiber diameters were performed using independent samples Mann-Whitney U, Kruskal-Wallis, and homogeneity of variance tests with a significance of p 0.05.The 365-μm fiber was more durable and less affected by burnback degradation than the 200-μm fiber (p 0.05). While initial power output varied between cleave techniques, all significance disappeared by 3 minutes. Power output decreased rapidly by a mean of 0.62 W over 4 minutes (p 0.05), following which there was no significant change.These findings confirm that initial laser fiber power output is significantly influenced by cleave technique, and the ceramic scissor is the optimal tool for cleaving between procedures. However, because of rapid fiber tip degradation and power loss, this study argues against routine cleaving to improve procedural efficiency in lengthy ureteroscopy cases.

Purpose Depression poses a significant public health burden, with varying prevalence by race/ethnicity, gender, and socioeconomic status (SES). It is unclear whether race/ethnicity and gender modify relationships between SES and depression. The purpose of this study was to investigate such effect modification. Methods A cross-sectional analysis was performed on Multi-Ethnic Study of Atherosclerosis participants at the baseline ( n = 5559). Multivariable logistic regression models stratified by race/ethnicity and gender were performed to evaluate associations between income, education, occupation, and neighborhood SES with depressive symptoms, defined by Center for Epidemiologic Studies Depression Scale values of 16 or greater. Results Depressive symptom odds were lower with increasing income, and this was pronounced in white women, black men, and Hispanic women. Lower odds of depressive symptoms were seen in management/professional occupations for Hispanic men, and in blacks as neighborhood SES increased. Education was not associated with odds of depressive symptoms. Multiplicative interaction terms were significant for gender-income ( P = .028) and race/ethnicity-neighborhood ( P = .010). Race/ethnicity-neighborhood interaction was also observed on the additive scale. Conclusions Associations varied across races/ethnicities and gender, and evidence for effect modification was seen by gender with income, and by race/ethnicity with neighborhood SES. These findings provide a nuanced understanding of race/ethnicity and gender differences in SES related to depressive symptoms.

INTRODUCTION AND OBJECTIVES: Ball tipped laser fibers have been introduced for laser lithotripsy with the intent to allow passage of the fiber through a deflected ureteroscope, without causing trauma to the working channel. We objectively compare a series of commercially available and prototype ball tipped fibers in order to characterize differences in performance characteristics and to compare them to a non-ball tipped variant (Flexiva 200, Boston Scientific). METHODS: A series of experiments were performed to evaluate (i) the insertion force needed to pass the fiber through a ureteroscope deflected to 240 degrees, (ii) the true diameter, (iii) the flexibility (max deflection in Stryker U-500), (iv) energy transmission pre and post testing, and (iv) the resistance to fracture with energy transmission during deflection. RESULTS: Results are summarized in Table 1. CONCLUSIONS: The Med Fibers Dome Tip had the lowest energy transmission. The Flexiva and Flexiva TracTip were the most resistant to fracture with energy transmission during deflection. Three of the four ball-tipped laser fibers required less force than the non-ball tipped fiber for insertion through a maximally deflected ureteroscope (p < 0.05). The Flexiva TracTip allows more facile insertion compared to other ball tipped fibers (p < 0.05) and performs on par or better than the Flexiva 200.

In this work we formulate vessel segmentation on contrast-enhanced CT angiogram images as a Bayesian tracking problem. To obtain posterior probability estimation of vessel location, we employ sequential Monte Carlo tracking and propose a new vessel segmentation method by fusing multiple cues extracted from CT images. These cues include intensity, vesselness, organ detection, and bridge information for poorly enhanced segments from global path minimization. By fusing local and global information for vessel tracking, we achieved high accuracy and robustness, with significantly improved precision compared to a traditional segmentation method (p = 0.0002). Our method was applied to the segmentation of the marginal artery of the colon, a small bore vessel of potential importance for colon segmentation and CT colonography. Experimental results indicate the effectiveness of the proposed method.