Development and evaluation of ensemble-based classification models for predicting unplanned hospital readmissions after hysterectomy

Unplanned hospital readmissions are a key indicator of quality in healthcare and can lead to high unnecessary costs for the hospital due to additional required resources or reduced payments by insurers or governments. Predictive analytics can support the identification of patients at high-risk for readmission early on to enable timely interventions. In Australia, hysterectomies present the 2nd highest observed readmission rates of all surgical procedures in public hospitals. Prior research so far only focuses on developing explanatory models to identify associated risk factors for past patients. In this study, we develop and compare 24 prediction models using state-of-the-art sampling and ensemble methods to counter common problems in readmission prediction, such as imbalanced data and poor performance of individual classifiers. The application and evaluation of these models are presented, resulting in an excellent predictive power with under- and oversampling and an additional slight increase in performance when combined with ensemble methods

Neighborhood Social Conditions Mediate the Association Between Physical Deterioration and Mental Health

This study investigates how neighborhood deterioration is associated with stress and depressive symptoms and the mediating effects of perceived neighborhood social conditions. Data come from a community survey of 801 respondents geocoded and linked to a systematic on‐site assessment of the physical characteristics of nearly all residential and commercial structures around respondents' homes. Structural equation models controlling for demographic effects indicate that the association between neighborhood deterioration and well‐being appear to be mediated through social contact, social capital, and perceptions of crime, but not through neighborhood satisfaction. Specifically, residential deterioration was mediated by social contact, then, social capital and fear of crime. Commercial deterioration, on the other hand, was mediated only through fear of crime. Additionally, data indicate that the functional definition of a “neighborhood” depends on the characteristics measured. These findings suggest that upstream interventions designed to improve neighborhood conditions as well as proximal interventions focused on social relationships, may promote well‐being.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117109/1/ajcp9139.pd

Semi-automated detection of fractional shortening in zebrafish embryo heart videos

Quantifying cardiac functions in model organisms like embryonic zebrafish is of high importance in small molecule screens for new therapeutic compounds. One relevant cardiac parameter is the fractional shortening (FS). A method for semi-automatic quantification of FS in video recordings of zebrafish embryo hearts is presented. The software provides automated visual information about the end-systolic and end-diastolic stages of the heart by displaying corresponding colored lines into a Motion-mode display. After manually marking the ventricle diameters in frames of end-systolic and end-diastolic stages, the FS is calculated. The software was evaluated by comparing the results of the determination of FS with results obtained from another established method. Correlations of 0.96 < r < 0.99 between the two methods were found indicating that the new software provides comparable results for the determination of the FS

Relationships Among Disease, Social Support, and Perceived Health: A Lifespan Approach

We examined the relationship between the cumulative presence of major disease (cancer, stroke, diabetes, heart disease, and hypertension), social support, and self‐reported general and emotional well‐being in a community representative sample of predominantly White and African American respondents (N = 1349). Across all ages, greater presence of disease predicted poorer reported general health, and predicted lower emotional well‐being for respondents 40 and above. In contrast, social support predicted better‐reported general and emotional well‐being. We predicted that different types of social support (blood relatives, children, friends, community members) would be relatively more important for health in different age groups based on a lifespan or life stage model. This hypothesis was supported; across all ages, social support was related to better reported general and emotional health, but sources of support differed by age. Broadly, those in younger age groups tended to list familial members as their strongest sources of support, whereas older group members listed their friends and community members. As a whole, social support mediated the effect of disease on reported well‐being, however, moderated mediation by type of support was not significant. The results are consistent with a lifespan approach to changing social ties throughout the life course.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/116357/1/ajcp9758.pd

Significant impact of different oxygen breathing conditions on noninvasive in vivo tumor-hypoxia imaging using [18F]-fluoro-azomycinarabino-furanoside ([18F]FAZA)

<p>Abstract</p> <p>Background</p> <p>[¹⁸F]FAZA is a PET biomarker with great potential for imaging tumor hypoxia. Aim of our study was to compare [¹⁸F]FAZA uptake in mice with subcutaneous exogenous CT26 colon carcinomas and endogenous polyoma middle-T (PyV-mT) mammary carcinomas and to analyze the influence of different breathing protocols in CT26 colon carcinomas as well as the reversibility or irreversibility of [¹⁸F]FAZA uptake.</p> <p>Methods</p> <p>We injected subcutaneous CT26 colon carcinoma or polyomavirus middle-T (PyV-mT) mammary carcinoma-bearing mice intravenously with¹⁸F-FAZA and performed PET scans 1-3 h post injection (<it>p.i.</it>). To analyze the impact of oxygen supply in CT26 carcinomas we used three different breathing protocols: (P0) air; (P1) 100% oxygen 1 h prior injection until 3 h <it>p.i.</it>; (P2) 100% oxygen breathing starting 2 min prior tracer injection until 1 h <it>p.i. </it>and during the PET scans; mice were breathing air between the 2 h and 3 h 10 min static scans. Normalized PET images were analyzed by using defined regions of interest. Finally, some mice were dissected for pimonidazole immunohistochemistry.</p> <p>Results</p> <p>There was no difference in¹⁸F-FAZA uptake 1-3 h <it>p.i. </it>between the two carcinoma types (CT26: 1.58 ± 0.45%ID/cc; PyV-mT: 1.47 ± 0.89%ID/cc, 1 h <it>p.i.</it>, tumor size < 0.5 cm³). We measured a significant tracer clearance, which was more pronounced in muscle tissue (P0). The [¹⁸F]FAZA tumor-to-muscle-ratios in CT26 colon carcinoma-bearing mice 2 h and 3 h, but not 1 h <it>p.i. </it>were significantly higher when the mice breathed air (P0: 3.56 ± 0.55, 3 h) compared to the oxygen breathing protocols (P1: 2.45 ± 0.58; P2: 2.77 ± 0.42, 3 h). Surprisingly, the breathing protocols P1 and P2 showed no significant differences in T/M ratios, thus indicating that the crucial [¹⁸F]FAZA uptake phase is during the first hour after [¹⁸F]FAZA injection. Importantly, the muscle clearance was not affected by the different oxygen breathing conditions while the tumor clearance was lower when mice were breathing air.</p> <p>Conclusion</p> <p>Exogenous CT26 colon carcinomas and endogenous polyoma middle-T (PyV-mT) mammary carcinomas showed no differences in [¹⁸F]FAZA uptake 1-3 h <it>p.i. </it>Our analysis using various breathing protocols with air (P0) and with pure oxygen (P1, P2) clearly indicate that [¹⁸F]FAZA is an appropriate PET biomarker for <it>in vivo </it>analysis of hypoxia revealing an enhanced tracer uptake in tumors with reduced oxygen supply. [¹⁸F]FAZA uptake was independent of tumor-type.</p

MIF Participates in Toxoplasma gondii-Induced Pathology Following Oral Infection

BACKGROUND: Macrophage migration inhibitory factor (MIF) is essential for controlling parasite burden and survival in a model of systemic Toxoplasma gondii infection. Peroral T. gondii infection induces small intestine necrosis and death in susceptible hosts, and in many aspects resembles inflammatory bowel disease (IBD). Considering the critical role of MIF in the pathogenesis of IBD, we hypothesized that MIF participates in the inflammatory response induced by oral infection with T. gondii. METHODOLOGY/PRINCIPAL FINDINGS: Mif deficient (Mif(-/-)) and wild-type mice in the C57Bl/6 background were orally infected with T. gondii strain ME49. Mif(-/-) mice had reduced lethality, ileal inflammation and tissue damage despite of an increased intestinal parasite load compared to wt mice. Lack of MIF caused a reduction of TNF-α, IL-12, IFN-γ and IL-23 and an increased expression of IL-22 in ileal mucosa. Moreover, suppressed pro-inflammatory responses at the ileal mucosa observed in Mif(-/-) mice was not due to upregulation of IL-4, IL-10 or TGF-β. MIF also affected the expression of matrix metalloproteinase-9 (MMP-9) but not MMP-2 in the intestine of infected mice. Signs of systemic inflammation including the increased concentrations of inflammatory cytokines in the plasma and liver damage were less pronounced in Mif(-/-) mice compared to wild-type mice. CONCLUSION/SIGNIFICANCE: In conclusion, our data suggested that in susceptible hosts MIF controls T. gondii infection with the cost of increasing local and systemic inflammation, tissue damage and death

Identification of Novel Genetic Loci Associated with Thyroid Peroxidase Antibodies and Clinical Thyroid Disease

Peer reviewe

Perceptions Mediate the Effects of Neighborhood Physical Conditions on Mental Health

This study investigates how neighborhood deterioration is associated with stress and depressive symptoms and the mediating effects of perceived neighborhood social conditions. Data come from a community survey of 801 respondents geocoded and linked to a systematic on-site assessment of the physical characteristics of nearly all residential and commercial structures around respondents’ homes. Structural equation models controlling for demographic effects indicate that the association between neighborhood deterioration and well-being appear to be mediated through social contact, social capital, and perceptions of crime, but not through neighborhood satisfaction. Specifically, residential deterioration was mediated by social contact, then, social capital and fear of crime. Commercial deterioration, on the other hand, was mediated only through fear of crime. Additionally, data indicate that the functional definition of a ‘‘neighborhood’’ depends on the characteristics measured. These findings suggest that upstream interventions designed to improve neighborhood conditions as well as proximal interventions focused on social relationships, may promote well-being

Perceptions Mediate the Effects of Neighborhood Physical Conditions on Mental Health

This study investigates how neighborhood deterioration is associated with stress and depressive symptoms and the mediating effects of perceived neighborhood social conditions. Data come from a community survey of 801 respondents geocoded and linked to a systematic on-site assessment of the physical characteristics of nearly all residential and commercial structures around respondents’ homes. Structural equation models controlling for demographic effects indicate that the association between neighborhood deterioration and well-being appear to be mediated through social contact, social capital, and perceptions of crime, but not through neighborhood satisfaction. Specifically, residential deterioration was mediated by social contact, then, social capital and fear of crime. Commercial deterioration, on the other hand, was mediated only through fear of crime. Additionally, data indicate that the functional definition of a ‘‘neighborhood’’ depends on the characteristics measured. These findings suggest that upstream interventions designed to improve neighborhood conditions as well as proximal interventions focused on social relationships, may promote well-being