Machine Learning Algorithm Detection of Confluent B-Lines.

OBJECTIVE: B-lines are a ring-down artifact of lung ultrasound that arise with increased alveolar water in conditions such as pulmonary edema and infectious pneumonitis. Confluent B-line presence may signify a different level of pathology compared with single B-lines. Existing algorithms aimed at B-line counting do not distinguish between single and confluent B-lines. The objective of this study was to test a machine learning algorithm for confluent B-line identification. METHODS: This study used a subset of 416 clips from 157 subjects, previously acquired in a prospective study enrolling adults with shortness of breath at two academic medical centers, using a hand-held tablet and a 14-zone protocol. After exclusions, random sampling generated a total of 416 clips (146 curvilinear, 150 sector and 120 linear) for review. A group of five experts in point-of-care ultrasound blindly evaluated the clips for presence/absence of confluent B-lines. Ground truth was defined as majority agreement among the experts and used for comparison with the algorithm. RESULTS: Confluent B-lines were present in 206 of 416 clips (49.5%). Sensitivity and specificity of confluent B-line detection by algorithm compared with expert determination were 83% (95% confidence interval [CI]: 0.77-0.88) and 92% (95% CI: 0.88-0.96). Sensitivity and specificity did not statistically differ between transducers. Agreement between algorithm and expert for confluent B-lines measured by unweighted κ was 0.75 (95% CI: 0.69-0.81) for the overall set. CONCLUSION: The confluent B-line detection algorithm had high sensitivity and specificity for detection of confluent B-lines in lung ultrasound point-of-care clips, compared with expert determination.

The Affordable Care Act: Disparities in emergency department use for mental health diagnoses in young adults.

BACKGROUND: There is little consensus as to the effects of insurance expansion on emergency department (ED) utilization for mental health purposes. We aimed to study the race specific association between the dependent coverage provision of the Affordable Care Act (ACA) and changes in young adults' usage of emergency department services for psychiatric diagnoses. METHODS: We utilized a Quasi-Experimental analysis of ED use in California from 2009-2011 for behavioral health diagnoses of individuals aged 19 to 31 years. Analysis used a difference-in-differences approach comparing those targeted by the ACA dependent provision (19-25 years) and those who were not (27 to 31 years), evaluating changes in ED visit rates per 1 000 in California. Primary outcomes measured included the quarterly ED visit rates with any psychiatric diagnosis. Subgroups were analyzed for differences based on race and gender. RESULTS: The ACA dependent provision was associated with 0.05 per 1 000 people fewer psychiatric ED visits among the treatment group (19-25 years) compared to the control group (27-31 years). Hispanics and Asian/Pacific Islanders were the only racial subgroups who did not see this significant reduction and were the only racial subgroups that did not see significant gains in the proportion of psychiatric ED visits covered by private insurance. CONCLUSION: The ACA dependent provision was associated with a modest reduction in the growth rate of ED use for psychiatric reasons, however, racial disparities in the effect of this provision exist for patients of Hispanic and Asian/Pacific Islander racial groups.

The Affordable Care Act: Disparities in emergency department use for mental health diagnoses in young adults / 世界急诊医学杂志（英文）

@#BACKGROUND: There is little consensus as to the effects of insurance expansion on emergency department (ED) utilization for mental health purposes. We aimed to study the race specific association between the dependent coverage provision of the Affordable Care Act (ACA) and changes in young adults' usage of emergency department services for psychiatric diagnoses. METHODS:We utilized a Quasi-Experimental analysis of ED use in California from 2009–2011 for behavioral health diagnoses of individuals aged 19 to 31 years. Analysis used a difference-in-differences approach comparing those targeted by the ACA dependent provision (19–25 years) and those who were not (27 to 31 years), evaluating changes in ED visit rates per 1000 in California. Primary outcomes measured included the quarterly ED visit rates with any psychiatric diagnosis. Subgroups were analyzed for differences based on race and gender. RESULTS:The ACA dependent provision was associated with 0.05 per 1000 people fewer psychiatric ED visits among the treatment group (19–25 years) compared to the control group (27–31 years). Hispanics and Asian/Pacific Islanders were the only racial subgroups who did not see this significant reduction and were the only racial subgroups that did not see significant gains in the proportion of psychiatric ED visits covered by private insurance. CONCLUSION:The ACA dependent provision was associated with a modest reduction in the growth rate of ED use for psychiatric reasons, however, racial disparities in the effect of this provision exist for patients of Hispanic and Asian/Pacific Islander racial groups.

Differential affinity of vitronectin versus collagen for synthetic biodegradable scaffolds for urethroplastic applications.

Cell-seeded synthetic polymer scaffolds constitute an emerging technology for urethroplastic applications. The study goal was to identify urethral proteins appropriate for cell attachment and optimize their adsorption onto two types of scaffolds: porous poly(ester urethane) with a poly(caprolactone) soft segment (PEU-PCL) and poly-(96% L/4% D)-lactic acid (P96L/4DLA). Specimens from eight men undergoing urethral reconstruction for stricture diseases were subjected to immunohistochemical analysis. Type I collagen, type IV collagen and vitronectin were detected at the interface between the epithelium and its basement membrane. Electrophoresis confirmed that polypeptide chains in the starting material were also present in fractions eluted from adsorbed scaffolds. Over a 4 week incubation assay, only vitronectin exhibited 100% retention levels for all scaffolds. The saturation point for each protein on each scaffold type was determined by titration and ELISA. The collective evidence indicates the concept that vitronectin > type IV collagen > type I collagen are preferred adsorption proteins for PEU-PCL and P96L/4DLA.

Dual sources of vitronectin in the human lower urinary tract: synthesis by urothelium vs. extravasation from the bloodstream.

Vitronectin (VN), secreted into the bloodstream by liver hepatocytes, is known to anchor epithelial cells to basement membranes through interactions with cell surface integrin receptors. We report here that VN is also synthesized by urothelial cells of urothelium in vivo and in vitro. In situ hybridization, dideoxy sequencing, immunohistochemistry, and ELISA of urothelial cell mRNA, cDNA, tissue, and protein extracts demonstrated that the VN gene is active in vivo and in vitro. The expression of VN by urothelium is hypothesized to constitute one of several pathways that anchor basal cells to an underlying substratum and explains why urothelial cells adhere to glass and propagate under serum-free conditions. Therefore, two sources of VN in the human urinary bladder are recognized: 1) localized synthesis by urothelial cells and 2) extravasation of liver VN through fenestrated capillaries. When human plasma was fractionated by denaturing heparin affinity chromatography, VN was isolated in a biologically active form that supported rapid spreading of urothelial cells in vitro under serum-free conditions. This activity was inhibited by the matricellular protein SPARC via direct binding of VN to SPARC through a Ca(+2)-dependent mechanism. A novel form of VN, isolated from the same heparin affinity chromatography column and designated as the VN(c) chromatomer, also supported cell spreading but failed to interact with SPARC. Therefore, the steady-state balance among urothelial cells, their extracellular milieu, and matricellular proteins constitutes a principal mechanism by which urothelia are anchored to an underlying substrata in the face of constant bladder cycling.