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Matthew J. O’Brien Ji Young Lee Mercedes R. Carnethon Ronald T. Ackermann Maria C. Vargas Andrew Hamilton Nivedita Mohanty Sarah S. Rittner Jessica N. Park Amro Hassan David R. Buchanan Lei Liu Joseph Feinglass 《PLoS medicine》2016,13(7)
BackgroundIn 2015, the United States Preventive Services Task Force (USPSTF) recommended targeted screening for prediabetes and diabetes (dysglycemia) in adults who are aged 40 to 70 y old and overweight or obese. Given increasing prevalence of dysglycemia at younger ages and lower body weight, particularly among racial/ethnic minorities, we sought to determine whether the current screening criteria may fail to identify some high-risk population subgroups.ConclusionsTargeted diabetes screening based on new USPSTF criteria may detect approximately half of adult community health center patients with undiagnosed dysglycemia and proportionately fewer racial/ethnic minorities than whites. Future research is needed to estimate the performance of these screening criteria in population-based samples. 相似文献
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Adi L. Tarca Edgar Hernandez-Andrade Hyunyoung Ahn Maynor Garcia Zhonghui Xu Steven J. Korzeniewski Homam Saker Tinnakorn Chaiworapongsa Sonia S. Hassan Lami Yeo Roberto Romero 《PloS one》2016,11(11)
ObjectivesTo assess the value of single and serial fetal biometry for the prediction of small- (SGA) and large-for-gestational-age (LGA) neonates delivered preterm or at term.MethodsA cohort study of 3,971 women with singleton pregnancies was conducted from the first trimester until delivery with 3,440 pregnancies (17,334 scans) meeting the following inclusion criteria: 1) delivery of a live neonate after 33 gestational weeks and 2) two or more ultrasound examinations with fetal biometry parameters obtained at ≤36 weeks. Primary outcomes were SGA (<5th centile) and LGA (>95th centile) at birth based on INTERGROWTH-21st gender-specific standards. Fetus-specific estimated fetal weight (EFW) trajectories were calculated by linear mixed-effects models using data up to a fixed gestational age (GA) cutoff (28, 32, or 36 weeks) for fetuses having two or more measurements before the GA cutoff and not already delivered. A screen test positive for single biometry was based on Z-scores of EFW at the last scan before each GA cut-off so that the false positive rate (FPR) was 10%. Similarly, a screen test positive for the longitudinal analysis was based on the projected (extrapolated) EFW at 40 weeks from all available measurements before each cutoff for each fetus.ResultsFetal abdominal and head circumference measurements, as well as birth weights in the Detroit population, matched well to the INTERGROWTH-21st standards, yet this was not the case for biparietal diameter (BPD) and femur length (FL) (up to 9% and 10% discrepancy for mean and confidence intervals, respectively), mainly due to differences in the measurement technique. Single biometry based on EFW at the last scan at ≤32 weeks (GA IQR: 27.4–30.9 weeks) had a sensitivity of 50% and 53% (FPR = 10%) to detect preterm and term SGA and LGA neonates, respectively (AUC of 82% both). For the detection of LGA using data up to 32- and 36-week cutoffs, single biometry analysis had higher sensitivity than longitudinal analysis (52% vs 46% and 62% vs 52%, respectively; both p<0.05). Restricting the analysis to subjects with the last observation taken within two weeks from the cutoff, the sensitivity for detection of LGA, but not SGA, increased to 65% and 72% for single biometry at the 32- and 36-week cutoffs, respectively. SGA screening performance was higher for preterm (<37 weeks) than for term cases (73% vs 46% sensitivity; p<0.05) for single biometry at ≤32 weeks.ConclusionsWhen growth abnormalities are defined based on birth weight, growth velocity (captured in the longitudinal analysis) does not provide additional information when compared to the last measurement for predicting SGA and LGA neonates, with both approaches detecting one-half of the neonates (FPR = 10%) from data collected at ≤32 weeks. Unlike for SGA, LGA detection can be improved if ultrasound scans are scheduled as close as possible to the gestational-age cutoff when a decision regarding the clinical management of the patient needs to be made. Screening performance for SGA is higher for neonates that will be delivered preterm. 相似文献
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Ahmad Chaddad Christian Desrosiers Ahmed Bouridane Matthew Toews Lama Hassan Camel Tanougast 《PloS one》2016,11(2)
Purpose
This paper proposes to characterize the continuum of colorectal cancer (CRC) using multiple texture features extracted from multispectral optical microscopy images. Three types of pathological tissues (PT) are considered: benign hyperplasia, intraepithelial neoplasia and carcinoma.Materials and Methods
In the proposed approach, the region of interest containing PT is first extracted from multispectral images using active contour segmentation. This region is then encoded using texture features based on the Laplacian-of-Gaussian (LoG) filter, discrete wavelets (DW) and gray level co-occurrence matrices (GLCM). To assess the significance of textural differences between PT types, a statistical analysis based on the Kruskal-Wallis test is performed. The usefulness of texture features is then evaluated quantitatively in terms of their ability to predict PT types using various classifier models.Results
Preliminary results show significant texture differences between PT types, for all texture features (p-value < 0.01). Individually, GLCM texture features outperform LoG and DW features in terms of PT type prediction. However, a higher performance can be achieved by combining all texture features, resulting in a mean classification accuracy of 98.92%, sensitivity of 98.12%, and specificity of 99.67%.Conclusions
These results demonstrate the efficiency and effectiveness of combining multiple texture features for characterizing the continuum of CRC and discriminating between pathological tissues in multispectral images. 相似文献156.
The persistence of species taxa within fragmented habitats is dependent on the source–sink metapopulation processes, and forest patch size and isolation are key factors. Unveiling species–patch area and/or species–patch isolation relationships may help provide crucial information for species and landscape management. In this study, relationship between forest patch size and isolation with abundance and occupancy probability of forest-dependent birds was investigated. This study was based within a coastal landscape that faces deleterious human activities such as clearing for agriculture. The study aimed to answer the question of whether the size and extent of isolation of forest patches influence abundance and/or occupancy probability of forest-specialist and generalist birds. Two bird species, namely Tiny Greenbul Phyllastrephus debilis subsp. rabai and Yellow-bellied Greenbul Chlorocichla flaviventris, were used as models. Birds were surveyed using distance sampling methods, and spatial metrics were measured from satellite imagery. Focal forest size and distance between forest patches were the most influential metrics whereby abundance and occupancy probabilities increased with increasing patch size, but were negatively influenced by increasing gaps between patches. These findings provide evidence of the existence of patch size/ isolation–occupancy relationships characterised by higher occupancy rate of large patches and distance-dependent dispersal, which decreased with increasing gaps between patches. Controlling deleterious human activities that reduce forest size should be a priority for the long-term conservation of forest-dependent birds. 相似文献
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The present study aimed to investigate the effects of different levels of dietary supplementation of grape seed extract (GSE) on growth performance, carcass traits and antioxidant status of rabbits under heat stress conditions (temperature humidity index 87.5–93.5). Weaned male New Zealand White (NZW) rabbits about 6 weeks old (n = 144, mean body weight 705 g) were randomly allotted to four dietary groups. The Control group was fed a basal diet without GSE; the experimental groups received the basal diet with 100, 200 and 300 mg GSE/kg (Groups 100 GSE, 200 GSE and 300 GSE, respectively). The experimental period lasted for 8 weeks. Compared with other groups, rabbits of Group 300 GSE had the best body weight gain and feed conversion ratio and the lowest mortality. Dietary GSE improved carcass weight, percentage of hot carcass, intestine and edible giblets, while total non-edible parts were reduced (p ≤ 0.05) in comparison with the Control group. In Groups 200 GSE and 300 GSE, plasma total protein, albumin and globulin were increased (p ≤ 0.05). In contrast, all supplementation levels of GSE reduced (p ≤ 0.05) the plasma concentrations of total lipids, total cholesterol, triglycerides and low-density lipoproteins. Antioxidant enzymes of rabbits (superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase) and total antioxidant capacity in blood were increased (p ≤ 0.05) by adding dietary GSE. However, malondialdehyde was reduced (p ≤ 0.001) with increasing GSE levels. Generally, grape seeds can be considered as rich source of phenolic and flavonoid compounds. The results of the study revealed that all tested levels of GSE were useful as a natural protection against heat stress to maintain performance, carcass traits and antioxidant status and could reduce the negative effects of heat stress in rabbits. 相似文献