5 research outputs found

    Assessment of Artifacts and Reproducibility across Spectral- and Time-Domain Optical Coherence Tomography Devices

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    Purpose To report the frequency of optical coherence tomography (OCT) scan artifacts and to compare macular thickness measurements, interscan reproducibility, and interdevice agreeability across 3 spectral-domain (SD) OCT (also known as Fourier domain; Cirrus HD-OCT, RTVue-100, and Topcon 3D-OCT 1000) devices and 1 time-domain (TD) OCT (Stratus OCT) device. Design Prospective, noncomparative, noninterventional case series. Participants Fifty-two patients seen at the New England Eye Center, Tufts Medical Center Retina Service, between February and August 2008. Methods Two scans were performed for each of the SD OCT protocols: Cirrus macular cube 512×128 (software version 3.0; Carl Zeiss Meditec, Inc., Dublin, CA), RTVue (E)MM5 and MM6 (software version 3.5; Optovue, Inc., Fremont, CA), Topcon 3D Macular and Radial (software version 2.12; Topcon, Inc., Paramus, NJ), in addition to 1 TD OCT scan via Stratus macular thickness protocol (software version 4.0; Carl Zeiss Meditec, Inc.). Scans were inspected for 6 types of OCT scan artifacts and were analyzed. Interscan reproducibility and interdevice agreeability were assessed by intraclass correlation coefficients (ICCs) and Bland-Altman plots, respectively. Main Outcome Measures Optical coherence tomography image artifacts, macular thickness, reproducibility, and agreeability. Results Time-domain OCT scans contained a significantly higher percentage of clinically significant improper central foveal thickness (IFT) after manual correction (11-μm change or more) compared with SD OCT scans. Cirrus HD-OCT had a significantly lower percentage of clinically significant IFT (11.1%) compared with the other SD OCT devices (Topcon 3D, 20.4%; Topcon Radial, 29.6%; RTVue (E)MM5, 42.6%; RTVue MM6, 24.1%; P = 0.001). All 3 SD OCT devices had central foveal subfield thicknesses that were significantly more than that of TD OCT after manual correction (P<0.0001). All 3 SD OCT devices demonstrated a high degree of reproducibility in the central foveal region (ICCs, 0.92–0.97). Bland-Altman plots showed low agreeability between TD and SD OCT scans. Conclusions Out of all OCT devices analyzed, cirrus HD-OCT scans exhibited the lowest occurrence of any artifacts (68.5%), IFT (40.7%), and clinically significant IFT (11.1%), whereas Stratus OCT scans exhibited the highest occurrence of clinically significant IFT. Further work on improving segmentation algorithm to decrease artifacts is warranted.Research to Prevent Blindness, Inc. (United States) (Challenge Grant)National Institutes of Health (U.S.) (Grant R01-EY11289-23)National Institutes of Health (U.S.) (Grant R01-EY13178-07)National Institutes of Health (U.S.) (Grant P30-EY008098)United States. Air Force Office of Scientific Research (Grant FA9550-07-1-0101)United States. Air Force Office of Scientific Research (Grant FA9550-07-1-0014

    Genome-wide meta-analyses of nonsyndromic cleft lip with or without cleft palate identify six new risk loci

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    We have conducted the first meta-analyses for nonsyndromic cleft lip with or without cleft palate (NSCL/P) using data from the two largest genome-wide association studies published to date. We confirmed associations with all previously identified loci and identified six additional susceptibility regions (1p36, 2p21, 3p11.1, 8q21.3, 13q31.1 and 15q22). Analysis of phenotypic variability identified the first specific genetic risk factor for NSCLP (nonsyndromic cleft lip plus palate) (rs8001641; P(NSCLP) = 6.51 × 10(-11); homozygote relative risk = 2.41, 95% confidence interval (CI) 1.84-3.16)

    Association between genes on chromosome 4p16 and non-syndromic oral clefts in four populations

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    Isolated cleft lip with or without cleft palate and cleft palate are among the most common human birth defects. Several candidate gene studies on MSX1 have shown significant association between markers in MSX1 and risk of oral clefts, and re-sequencing studies have identified multiple mutations in MSX1 in a small minority of cases, which may account for 1–2% of all isolated oral clefts cases. We explored the 2-Mb region around MSX1, using a marker map of 393 single nucleotide polymorphisms (SNPs) in 297 cleft lip, with or without cleft palate, case–parent trios and 84 cleft palate trios from Maryland, Taiwan, Singapore, and Korea. Both individual markers and haplotypes of two to five SNPs showed several regions yielding statistical evidence for linkage and disequilibrium. Two genes (STK32B and EVC) yielded consistent evidence from cleft lip, with or without cleft palate, trios in all four populations. These two genes plus EVC2 also yielded suggestive evidence for linkage and disequilibrium among cleft palate trios. This analysis suggests that several genes, not just MSX1, in this region may influence risk of oral clefts

    The effects of social capital and organizational innovativeness in different institutional contexts

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    This paper examines how social capital and organizational innovativeness influence business performance through their separate, indirect, or interactive effects, and how these effects differ across the institutional contexts of a transition economy and a market economy. In line with institutional theory, our findings show that the effects of social capital are more extensive and probably more malignant in a transition economy than in a market economy. Furthermore, different types of organizational innovativeness, as corporate culture, can be cultivated by different forms of social capital in different institutional contexts. The implications for institutional theory and social capital theory, and the managerial implications, are discussed. Journal of International Business Studies (2008) 39, 589–612. doi:10.1057/palgrave.jibs.8400373
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