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2.
Sensors (Basel) ; 23(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37896452

RESUMO

A multichannel soft X-ray (SXR) array has been developed to measure the electron temperature in the Versatile Experiment Spherical Torus (VEST). To estimate electron temperature using the two-filter method applied to SXR intensity, we designed a pinhole camera that has two photodiode arrays with different metallic filters. We also adopted a filter wheel and tested various filter parameters to find the optimal filter set. Through tests, the combination of aluminum and beryllium was found to be the most suitable for the current experimental conditions in VEST. The filtered SXR signals were acquired with a low-noise preamplifier, exhibiting sufficient signal-to-noise ratios for electron temperature estimation based on the intensity ratio of two signals obtained with different filters. The estimated electron temperature from the developed two-filter SXR array showed reasonably matched levels and consistent trends with Thomson scattering measurements. Error contribution from impurity line emission is also discussed.

3.
Ophthalmol Sci ; 3(4): 100325, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37292179

RESUMO

Purpose: To determine the interreader agreement for reticular pseudodrusen (RPD) assessment on combined infrared reflectance (IR) and OCT imaging in the early stages of age-related macular degeneration across a range of different criteria to define their presence. Design: Interreader agreement study. Participants: Twelve readers from 6 reading centers. Methods: All readers evaluated 100 eyes from individuals with bilateral large drusen for the following: (1) the presence of RPD across a range of different criteria and (2) the number of Stage 2 or 3 RPD lesions (from 0 to ≥ 5 lesions) on an entire OCT volume scan and on a selected OCT B-scan. Supportive information was available from the corresponding IR image. Main Outcome Measures: Interreader agreement, as assessed by Gwet's first-order agreement coefficient (AC1). Results: When evaluating an entire OCT volume scan, there was substantial interreader agreement for the presence of any RPD, any or ≥ 5 Stage 2 or 3 lesions, and ≥ 5 definite lesions on en face IR images corresponding to Stage 2 or 3 lesions (AC1 = 0.60-0.72). On selected OCT B-scans, there was also moderate-to-substantial agreement for the presence of any RPD, any or ≥ 5 Stage 2 or 3 lesions (AC1 = 0.58-0.65) and increasing levels of agreement with increasing RPD stage (AC1 = 0.08, 0.56, 0.78, and 0.99 for the presence of any Stage 1, 2, 3, and 4 lesions, respectively). There was substantial agreement regarding the number of Stage 2 or 3 lesions on an entire OCT volume scan (AC1 = 0.68), but only fair agreement for this evaluation on selected B-scans (AC1 = 0.30). Conclusions: There was generally substantial or near-substantial-but not near-perfect-agreement for assessing the presence of RPD on entire OCT volume scans or selected B-scans across a range of differing RPD criteria. These findings underscore how interreader variability would likely contribute to the variability of findings related to the clinical associations of RPD. The low levels of agreement for assessing RPD number on OCT B-scans underscore the likely challenges of quantifying RPD extent with manual grading. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.

4.
Epidemiol Psychiatr Sci ; 32: e9, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36762596

RESUMO

AIMS: Obsessive-compulsive disorder (OCD) and schizophrenia are often reported as co-morbid conditions. However, the evidence of an association between OCD and the risk of schizophrenia is limited. This study investigated the risk of schizophrenia in patients newly diagnosed with OCD using a nationally representative sample cohort in South Korea. METHODS: Data were obtained from the 2002-2013 Korean National Health Insurance Service-National Sample Cohort of the National Health Insurance Service. Using propensity score matching, 2509 patients with OCD and a control group of 7527 patients were included in the analysis. Chi-squared tests were used to investigate and compare the general characteristics of the study population. The risk of schizophrenia was analysed using the Cox proportional hazard model. RESULTS: The incidence rate was 45.79/10 000 person-year for patients with OCD and 4.19/10 000 person-year for patients without OCD. Patients with OCD had a higher risk of schizophrenia compared to the control group after adjusting for covariates (hazard ratio = 10.46, 95% confidence interval = 6.07-18.00). CONCLUSIONS: This study identified an association between the diagnosis of OCD and the risk of schizophrenia in a South Korean national representative cohort. Further research using a prospective design to clarify the causality of OCD in schizophrenia in a controlled environment should be conducted to validate these findings.


Assuntos
Transtorno Obsessivo-Compulsivo , Esquizofrenia , Humanos , Esquizofrenia/epidemiologia , Esquizofrenia/complicações , Estudos Retrospectivos , Transtorno Obsessivo-Compulsivo/epidemiologia , Fatores de Risco , Programas Nacionais de Saúde , Comorbidade
5.
Ophthalmol Retina ; 7(2): 111-117, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35940477

RESUMO

PURPOSE: To identify the prevalence of extramacular drusen and their role in the progression of age-related macular degeneration (AMD). DESIGN: Retrospective analysis of a prospective cohort study. PARTICIPANTS: The study was conducted in 4168 eyes (2998 participants) with intermediate AMD in one or both eyes enrolled in the Age-Related Eye Disease Study 2 (AREDS2), a 5-year multicenter study of nutritional supplements. METHODS: Baseline 3-field 30-degree color photographs were evaluated for drusen characteristics outside the macular grid, including size, area, and location. The characteristics of extramacular drusen were compared with those of drusen within the macula. MAIN OUTCOME MEASURES: Progression rates to late AMD. RESULTS: Although extramacular drusen were observed in 3624 (86.9%) eyes, they represented a small area (< 0.5 mm2) in 50.3% of eyes, with only 17.5% exhibiting an area of > 1 disc area. Eyes with extramacular drusen exhibited larger macular drusen size and area than eyes without extramacular drusen (P < 0.001). Extramacular drusen were not associated with progression to late AMD. The hazard ratio adjusted for baseline age, sex, smoking, AMD severity level, and reticular pseudodrusen for 4043 eyes at risk of developing late AMD over 5 years was 1.17 (95% confidence interval [CI], 0.88-1.54; P = 0.27) for geographic atrophy and 0.96 (95% CI, 0.76-1.2; P = 0.7) for neovascular AMD. CONCLUSIONS: Extramacular drusen are commonly observed in eyes with AMD and are more frequent with an increasing drusen burden within the macula. In eyes with intermediate AMD, extramacular drusen do not confer additional risk to previously identified risk factors in progression to late AMD.


Assuntos
Degeneração Macular , Drusas Retinianas , Humanos , Inibidores da Angiogênese/uso terapêutico , Estudos Prospectivos , Drusas Retinianas/complicações , Drusas Retinianas/diagnóstico , Drusas Retinianas/epidemiologia , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular , Acuidade Visual , Degeneração Macular Exsudativa/etiologia , Degeneração Macular/etiologia
6.
Ophthalmol Sci ; 2(4): 100191, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36531589

RESUMO

Objective: To evaluate changes in retinal thickness and morphology using OCT in youth with type 2 diabetes (T2D) and to identify systemic biomarkers correlating with these changes. Design: Retrospective subgroup analysis of a prospective study. Participants: Participants who underwent OCT imaging in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) trial and its follow-up study TODAY2. Methods: In 2010-2011 (TODAY) and 2017-2018 (TODAY2), 6 × 6-mm macular volume OCT scans were acquired, segmented, and analyzed to generate total retinal thickness, inner retinal thickness, and outer retinal thickness. The main retinal morphologies graded were intraretinal cystoid spaces, subretinal fluid, and posterior vitreous detachment (PVD). Main Outcome Measures: Changes in total and individual retinal layer thickness and development of abnormal vitreomacular morphology between TODAY and TODAY2. Results: Participants had a mean age of 17.9 ± 2.4 years and glycated hemoglobin (HbA1c) of 8.2 ± 2.8% in TODAY and a mean age of 25.0 ± 2.4 years and mean HbA1c of 9.5 ± 2.8% in TODAY2. Longitudinally between assessments, there were overall decreases in outer retinal thickness from 167.2 ± 11.5 microns to 158.4 ± 12.8 microns (P < 0.001) and in photoreceptor thickness from 30.3 ± 2.9 microns to 29.8 ± 4.1 microns (P = 0.04) in the central subfield, while in the inner subfield, we noted a decrease in outer retinal thickness from 150.5 ± 10.1 microns to 144.9 ± 10.5 microns (P < 0.001) and an increase in inner retinal thickness from 136.9 ± 11.5 microns to 137.4 ± 12.6 microns (P = 0.01). Multivariate analysis showed that in the center subfield, HbA1c increases were associated with increases in total retinal thickness (r: 0.67, P = 0.001), whereas fasting glucose was positively correlated with inner retinal thickness (r: 0.02, P = 0.02). In the inner subfield, both systolic (r: -0.22, P < 0.001) and diastolic (r: -0.22, P = 0.003) blood pressures were negatively correlated with total retinal thickness. There was an increase in PVD (18.9%) and cystoid spaces (4.2%). Conclusions: Youth with T2D develop retinal thickness changes on OCT, including increases in total retinal and inner retinal thickness in the center subfield that correlate with HbA1c and fasting glucose, respectively. Taken together with the increased prevalence of abnormal vitreomacular morphology in this cohort at risk, these findings emphasize the importance of controlling risk factors to prevent the development of sight-threatening retinal complications.

7.
Ophthalmol Retina ; 6(9): 835-846, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35339727

RESUMO

PURPOSE: There is growing evidence of a direct association between pentosan polysulfate (PPS) therapy and the development of macular changes. Using standardized visual acuity (VA) testing and multimodal imaging, we investigated the impact of PPS therapy on vision and described an expanded spectrum of imaging findings among PPS users. DESIGN: Cross-sectional screening study. PARTICIPANTS: Thirty-nine patients who were current or recent users of PPS. METHODS: The participants underwent a brief eye examination and answered a comprehensive medical and ophthalmic history questionnaire. Color fundus photography, fundus autofluorescence (FAF), and spectral-domain OCT (SD-OCT) were performed. The images were evaluated by expert graders at Wisconsin Reading Center. Abnormalities were categorized as definite toxicity (DT) if seen on both FAF and SD-OCT and as questionable toxicity (QT) if seen on either FAF or SD-OCT. MAIN OUTCOME MEASURES: ETDRS and Snellen VA, the dosage and duration of PPS exposure, and the prevalence of retinal toxicity on imaging. RESULTS: The mean ETDRS and Snellen VA of the study cohort were 85 letters and 20/22, respectively. The mean PPS daily dose was 282 mg (range, 88-400 mg), whereas the mean cumulative dose was 915 g (range, 19-3650 g) over a mean period of 8.8 years (range, 2 months-25 years). There was evidence of retinopathy in 41% of the eyes; DT was identified in 24 eyes (31%) and QT in 8 eyes (10%). Retinal pigment epithelium (RPE) abnormalities (thickening or thinning or both) were present in all eyes with DT. Retinal pigment epithelium atrophy was seen in 7 eyes (9%). In addition to well-established findings, the unique SD-OCT features of this cohort included interdigitation zone abnormalities and the presence of a flying saucer-type defect. Fundus autofluorescence abnormalities were seen in 24 eyes (30.8%), with 20 (66.7%) of these exhibiting abnormalities located outside the central subfield and extending beyond the arcades. CONCLUSIONS: Findings from the masked grading of multimodal imaging at a centralized reading center suggest a wider phenotypic spectrum of structural abnormalities among patients taking PPS. Macular changes selectively involve the RPE and outer retina, with a range of findings often seen beyond the arcades. The subtle and atypical findings in this cohort should prompt clinicians to consider lowering the threshold for diagnosing PPS retinopathy.


Assuntos
Poliéster Sulfúrico de Pentosana , Degeneração Retiniana , Estudos Transversais , Angiofluoresceinografia/métodos , Humanos , Imagem Multimodal , Poliéster Sulfúrico de Pentosana/efeitos adversos , Tomografia de Coerência Óptica/métodos
8.
Ophthalmol Retina ; 6(1): 4-14, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766801

RESUMO

PURPOSE: To determine the interreader agreement for incomplete retinal pigment epithelium (RPE) and outer retinal atrophy (iRORA) and complete RPE and outer retinal atrophy (cRORA) and their related features in age-related macular degeneration (AMD). DESIGN: Interreader agreement study. PARTICIPANTS: Twelve readers from 6 reading centers. METHODS: After formal training, readers qualitatively assessed 60 OCT B-scans from 60 eyes with AMD for 9 individual features associated with early atrophy and performed 7 different annotations to quantify the spatial extent of OCT features within regions of interest. The qualitative and quantitative features were used to derive the presence of iRORA and cRORA and also in an exploratory analysis to examine if agreement could be improved using different combinations of features to define OCT atrophy. MAIN OUTCOME MEASURES: Interreader agreement based on Gwet's first-order agreement coefficient (AC1) for qualitatively graded OCT features and classification of iRORA and cRORA, and smallest real difference (SRD) for quantitatively graded OCT features. RESULTS: Substantial or better interreader agreement was observed for all qualitatively graded OCT features associated with atrophy (AC1 = 0.63-0.87), except for RPE attenuation (AC1 = 0.46) and disruption (AC1 = 0.26). The lowest SRD for the quantitatively graded horizontal features was observed for the zone of choroidal hypertransmission (± 190.8 µm). Moderate agreement was found for a 3-category classification of no atrophy, iRORA, and cRORA (AC1 = 0.53). Exploratory analyses suggested a significantly higher level of agreement for a 3-category classification using (1) no atrophy; (2) presence of inner nuclear layer and outer plexiform layer subsidence, or a hyporeflective wedge-shaped band, as a less severe atrophic grade; and (3) the latter plus an additional requirement of choroidal hypertransmission of 250 µm or more for a more severe atrophic grade (AC1 = 0.68; P = 0.013). CONCLUSIONS: Assessment of iRORA and cRORA, and most of their associated features, can be performed relatively consistently and robustly. A refined combination of features to define early atrophy could further improve interreader agreement.


Assuntos
Corioide/diagnóstico por imagem , Diagnóstico Precoce , Angiofluoresceinografia/métodos , Atrofia Geográfica/diagnóstico , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Fundo de Olho , Humanos , Curva ROC
9.
Invest Ophthalmol Vis Sci ; 62(9): 20, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34254974

RESUMO

Purpose: We investigated whether dietary carotenoids lutein and zeaxanthin (L/Z) in the serum and macula were associated with central retinal arteriole and venule calibers in a follow-up ancillary study among older women in the Women's Health Initiative. Methods: Among 390 women who participated in Carotenoids in Age-Related Eye Disease Study 2 (CAREDS2) (2016-2019), we investigated associations between serum L/Z at Women's Health Initiative baseline (1994-1998), and macular pigment optical density (MPOD) at CAREDS baseline (2001-2004), with central retinal vessel caliber in CAREDS2. MPOD was measured using heterochromatic flicker photometry (0.5° from the foveal center) in CAREDS baseline and CAREDS2. Vessel calibers were measured from fundus photographs (CAREDS2). We also explored associations in women with stable MPOD (±0.10 optical density units) over 15 years (n = 106), given the long-term increases in MPOD related to diet patterns and supplement use. Associations were investigated using linear modeling. Results: In the full sample (n = 390), higher serum L/Z (tertile 3 vs. 1) was positively associated with arteriole caliber (mean ± SE, 145.0 ± 1.4 µm vs. 140.8 ± 1.4 µm; P = 0.05) and venule caliber (214.6 ± 2.2 µm vs. 207.5 ± 2.2 µm; P = 0.03). MPOD was also associated with wider vessel calibers (tertile 3 vs. 1), but the trend was only statistically significant for venules (144.4 ± 1.4 µm vs. 141.1 ± 1.4 µm [P = 0.12] and 213.3 ± 2.1 µm vs. 206.0 ± 2.1 µm [P = 0.02], respectively.) Most associations were strengthened in women with stable MPOD over 15 years, including between MPOD and arteriole caliber (149.8 ± 2.6 µm vs.135.8 ± 3.0 µm; P = 0.001). Conclusions: Higher L/Z status in serum and retina was associated with larger central retinal vessel calibers. Prospective studies and clinical trials are needed to elucidate whether L/Z supplementation prevents vision loss through increasing blood flow.


Assuntos
Carotenoides/metabolismo , Previsões , Macula Lutea/metabolismo , Degeneração Macular/metabolismo , Vasos Retinianos/fisiopatologia , Acuidade Visual , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Progressão da Doença , Feminino , Seguimentos , Humanos , Macula Lutea/patologia , Degeneração Macular/diagnóstico , Degeneração Macular/fisiopatologia , Masculino , Estudos Prospectivos , Pigmentos da Retina/metabolismo , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia
10.
Ophthalmol Retina ; 5(8): 721-729, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33387684

RESUMO

PURPOSE: To determine the prevalence and morphologic features of reticular pseudodrusen (RPD) and their association with participant demographics and age-related macular degeneration (AMD) status in the Carotenoids in Age-Related Eye Disease Study 2 (CAREDS2) sample, an ancillary study of the Women's Health Initiative Observational Study. DESIGN: Cross-sectional, multicenter, natural history study. PARTICIPANTS: Nine hundred and twenty-seven eyes from 466 postmenopausal women 69 to 101 years of age. METHODS: Multimodal imaging, including spectral-domain (SD) OCT and infrared reflectance (IR), were used to identify RPD characteristics, including location (within or outside the 6-mm diameter circle centered at the macula), presence of peripapillary RPD, pattern of RPD, and RPD area. Age-related macular degeneration features from SD OCT, IR, and color photographs also were assessed and AMD severity was categorized. MAIN OUTCOME MEASURES: Reticular pseudodrusen prevalence using SD OCT and IR imaging and AMD status. RESULTS: Reticular pseudodrusen were present in 130 eyes (14% of eyes, 16% of participants), with increasing prevalence with age: 7% in those younger than 78 years, 14% in those 78 to 83 years of age, and 30% in those older than 83 years. Using clinical classification of AMD with color photography, RPD were seen in 2.4% of eyes with no AMD or aging changes, 11.5% in early AMD, 25.1% in intermediate AMD, and 51.1% in late AMD. Mean RPD area was 17.4 mm2 (standard deviation, 14.7 mm2). Ribbon morphologic RPD (53%) was more common than dot morphologic RPD (36%). Reticular pseudodrusen mostly were located both within and outside the 6-mm circle with primarily superior retinal distribution. Reticular pseudodrusen were visualized with corresponding color fundus photography in only 38 eyes (4% of total eyes). Participants with and without RPD had a visual acuity±standard error of 77.9 ± 1.4 letters and 81.3 ± 0.4 letters, respectively (P = 0.02). CONCLUSIONS: The prevalence of RPD in CAREDS2 increased with age and was associated with AMD severity. Reticular pseudodrusen were detected in eyes without other features of AMD and could represent an earlier disease state. Multimodal imaging with SD OCT and IR has significantly greater sensitivity for visualizing RPD than color fundus photography.


Assuntos
Carotenoides/farmacologia , Degeneração Macular/tratamento farmacológico , Imagem Multimodal/métodos , Drusas Retinianas/epidemiologia , Acuidade Visual , Saúde da Mulher , Idoso , Idoso de 80 Anos ou mais , Antioxidantes/farmacologia , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Fundo de Olho , Humanos , Macula Lutea/diagnóstico por imagem , Degeneração Macular/complicações , Degeneração Macular/epidemiologia , Oftalmoscopia , Prognóstico , Drusas Retinianas/diagnóstico , Drusas Retinianas/etiologia , Tomografia de Coerência Óptica/métodos , Estados Unidos/epidemiologia
11.
AJNR Am J Neuroradiol ; 41(12): 2320-2326, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33060104

RESUMO

BACKGROUND AND PURPOSE: Transoral robotic surgery is an emerging strategy for treating human papillomavirus-positive cancers, but the role of MR imaging in predicting the surgical outcome has not been established. We aimed to identify preoperative MR imaging characteristics that predispose the outcome of transoral robotic surgery toward an insecure (positive or close) surgical margin in human papillomavirus-positive tonsillar squamous cell carcinoma. MATERIALS AND METHODS: Between December 2012 and May 2019, sixty-nine patients underwent transoral robotic surgery at our institution. Among these, 29 who were diagnosed with human papillomavirus-positive tonsillar squamous cell carcinoma, did not receive neoadjuvant treatment, underwent preoperative 3T MR imaging, and had postoperative pathologic reports and were included in this retrospective study. Two neuroradiologists evaluated the preoperative MR imaging scans to determine the tumor spread through the pharyngeal constrictor muscle using a 5-point scale: 1, normal constrictor; 2, bulging constrictor; 3, thinning constrictor; 4, obscured constrictor; and 5, tumor protrusion into the parapharyngeal fat. The risk of an insecure surgical margin (involved or <1 mm) according to the MR imaging scores was predicted using logistic regression with the Firth correction. RESULTS: The interobserver agreement for the MR imaging scores was excellent (κ = 0.955, P < .001). A score of ≥4 could predict an insecure margin with 87.5% sensitivity and 92.3% specificity (area under the curve = 0.899) and was the only significant factor associated with an insecure margin in the multivariable analysis (OR, 6.59; 95% CI, 3.11-22.28; P < .001). CONCLUSIONS: The pre-transoral robotic surgery MR imaging scoring system for the pharyngeal constrictor muscle is a promising predictor of the surgical margin in human papillomavirus-positive tonsillar squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/cirurgia , Margens de Excisão , Neoplasias Tonsilares/diagnóstico por imagem , Neoplasias Tonsilares/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/virologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculos/diagnóstico por imagem , Músculos/patologia , Infecções por Papillomavirus/complicações , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Cirurgia Assistida por Computador/métodos , Neoplasias Tonsilares/virologia , Resultado do Tratamento
12.
JACC Cardiovasc Imaging ; 13(10): 2162-2173, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32682719

RESUMO

OBJECTIVES: This study sought to identify culprit lesion (CL) precursors among acute coronary syndrome (ACS) patients based on qualitative and quantitative computed tomography-based plaque characteristics. BACKGROUND: Coronary computed tomography angiography (CTA) has been validated for patient-level prediction of ACS. However, the applicability of coronary CTA to CL assessment is not known. METHODS: Utilizing the ICONIC (Incident COroNary Syndromes Identified by Computed Tomography) study, a nested case-control study of 468 patients with baseline coronary CTA, the study included ACS patients with invasive coronary angiography-adjudicated CLs that could be aligned to CL precursors on baseline coronary CTA. Separate blinded core laboratories adjudicated CLs and performed atherosclerotic plaque evaluation. Thereafter, the study used a boosted ensemble algorithm (XGBoost) to develop a predictive model of CLs. Data were randomly split into a training set (80%) and a test set (20%). The area under the receiver-operating characteristic curve of this model was compared with that of diameter stenosis (model 1), high-risk plaque features (model 2), and lesion-level features of CL precursors from the ICONIC study (model 3). Thereafter, the machine learning (ML) model was applied to 234 non-ACS patients with 864 lesions to determine model performance for CL exclusion. RESULTS: CL precursors were identified by both coronary angiography and baseline coronary CTA in 124 of 234 (53.0%) patients, with a total of 582 lesions (containing 124 CLs) included in the analysis. The ML model demonstrated significantly higher area under the receiver-operating characteristic curve for discriminating CL precursors (0.774; 95% confidence interval [CI]: 0.758 to 0.790) compared with model 1 (0.599; 95% CI: 0.599 to 0.599; p < 0.01), model 2 (0.532; 95% CI: 0.501 to 0.563; p < 0.01), and model 3 (0.672; 95% CI: 0.662 to 0.682; p < 0.01). When applied to the non-ACS cohort, the ML model had a specificity of 89.3% for excluding CLs. CONCLUSIONS: In a high-risk cohort, a boosted ensemble algorithm can be used to predict CL from non-CL precursors on coronary CTA.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Algoritmos , Estudos de Casos e Controles , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Estenose Coronária , Humanos , Valor Preditivo dos Testes , Índice de Gravidade de Doença
14.
PLoS One ; 15(5): e0232573, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374784

RESUMO

OBJECTIVES: To develop, demonstrate and evaluate an automated deep learning method for multiple cardiovascular structure segmentation. BACKGROUND: Segmentation of cardiovascular images is resource-intensive. We design an automated deep learning method for the segmentation of multiple structures from Coronary Computed Tomography Angiography (CCTA) images. METHODS: Images from a multicenter registry of patients that underwent clinically-indicated CCTA were used. The proximal ascending and descending aorta (PAA, DA), superior and inferior vena cavae (SVC, IVC), pulmonary artery (PA), coronary sinus (CS), right ventricular wall (RVW) and left atrial wall (LAW) were annotated as ground truth. The U-net-derived deep learning model was trained, validated and tested in a 70:20:10 split. RESULTS: The dataset comprised 206 patients, with 5.130 billion pixels. Mean age was 59.9 ± 9.4 yrs., and was 42.7% female. An overall median Dice score of 0.820 (0.782, 0.843) was achieved. Median Dice scores for PAA, DA, SVC, IVC, PA, CS, RVW and LAW were 0.969 (0.979, 0.988), 0.953 (0.955, 0.983), 0.937 (0.934, 0.965), 0.903 (0.897, 0.948), 0.775 (0.724, 0.925), 0.720 (0.642, 0.809), 0.685 (0.631, 0.761) and 0.625 (0.596, 0.749) respectively. Apart from the CS, there were no significant differences in performance between sexes or age groups. CONCLUSIONS: An automated deep learning model demonstrated segmentation of multiple cardiovascular structures from CCTA images with reasonable overall accuracy when evaluated on a pixel level.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Vasos Coronários/diagnóstico por imagem , Aprendizado Profundo , Coração/diagnóstico por imagem , Idoso , Feminino , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade
15.
Vet Med Sci ; 6(3): 447-453, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32323490

RESUMO

We examined the effect of ice-binding protein derived from Leucosporidium (LeIBP) on the cryopreservation of bull semen and compared it with that derived from previously reported Antifreeze Protein III (AFPIII). Six concentrations of LeIBP (10-1  ~ 104  µg/ml) and AFPIII (10-1  ~ 104  µg/ml) were added to the bull semen extender, respectively. Sperm kinematic parameters were measured to examine sperm toxicity and cryopreserved sperm quality. Measures of antioxidant activity such as superoxide dismutase (SOD), reduced glutathione/oxidative glutathione (GSH/GSSG), and total antioxidant capacity (TAC) were analysed to identify the effect of LeIBP on sperm quality. In addition, sperm viability was analysed using a flow cytometer and fluorescence microscope by SYBR14/PI staining. The results showed that the LeIBP groups (0.1, 1 and 10 µg/ml) were less toxic, and the quality of the sperm were dramatically improved in the extenders containing 0.1 µg/ml LeIBP among concentrations of LeIBP and AFPIII. The SOD activity of LeIBP was greater than that of AFPIII and control. In addition, sperm viability was enhanced in the LeIBP-treated group. In summary, LeIBP is a useful cryoprotective adjuvant for bull sperm cryopreservation, and the most efficient concentration of LeIBP is 0.1 µg/ml.


Assuntos
Basidiomycota/química , Proteínas de Transporte/farmacologia , Bovinos/fisiologia , Criopreservação/veterinária , Crioprotetores/farmacologia , Preservação do Sêmen/veterinária , Sêmen/efeitos dos fármacos , Animais , Criopreservação/métodos , Gelo , Masculino , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos
16.
ACS Appl Mater Interfaces ; 12(13): 15239-15245, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32150374

RESUMO

Z-scheme transfer is an ideal photocatalytic system with stronger redox ability, but its design and construction still lack understanding. Herein, the work function difference and the band bending are found to be the determining factors for the construction of the Z-scheme transfer mechanism of photoexcited charges in TiO2/WO3. The control of work function and band bending achieved by carbon insertion results from the hybridization of orbitals and redistribution of electron density, as demonstrated by ultraviolet photoelectron spectroscopy and photocatalytic analysis. The heterojunction system, TiO2/WO3, with controlled work function and band bending, shows 2 times faster •OH radical formation rate (0.011 µmol min-1) compared to the undisturbed system. First-principles calculation reveals that the changes in work function and band bending result in an interfacial electric field, which shifts the charge transfer mechanism from type II to Z-scheme. This work proves that the design of work function and band bending allows reconstructing charge transfer mechanism by forming the interfacial electric field in heterojunction systems.

17.
Bone Joint J ; 102-B(2): 227-231, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32009431

RESUMO

AIMS: The purpose of this study was to evaluate the relationships between the degree of injury to the medial and lateral collateral ligaments (MCL and LCL) and associated fractures in patients with a posterolateral dislocation of the elbow, using CT and MRI. METHODS: We retrospectively reviewed 64 patients who presented between March 2009 and March 2018 with a posterolateral dislocation of the elbow and who underwent CT and MRI. CT revealed fractures of the radial head, coronoid process, and medial and lateral humeral epicondyles. MRI was used to identify contusion of the bone and collateral ligament injuries by tear, partial or complete tear. RESULTS: A total of 54 patients had a fracture; some had more than one. Radial head fractures were found in 25 patients and coronoid fractures in 42. Lateral and medial humeral epicondylar fractures were found in eight and six patients, respectively. Contusion of the capitellum was found in 43 patients and rupture of the LCL was seen in all patients (partial in eight and complete in 56), there was complete rupture of the MCL in 37 patients, partial rupture in 19 and eight had no evidence of rupture. The LCL tear did not significantly correlate with the presence of fracture, but the MCL rupture was complete in patients with a radial head fracture (p = 0.047) and there was significantly increased association in those without a coronoid fracture (p = 0.015). CONCLUSION: In posterolateral dislocation of the elbow, LCL ruptures are mostly complete, while the MCL exhibits various degrees of injury, which are significantly associated with the associated fractures. Cite this article: Bone Joint J 2020;102-B(2):227-231.


Assuntos
Ligamentos Colaterais/diagnóstico por imagem , Articulação do Cotovelo/diagnóstico por imagem , Fraturas do Úmero/diagnóstico por imagem , Luxações Articulares/diagnóstico por imagem , Fraturas do Rádio/diagnóstico por imagem , Fraturas da Ulna/diagnóstico por imagem , Adulto , Idoso , Ligamentos Colaterais/lesões , Feminino , Humanos , Fraturas do Úmero/complicações , Luxações Articulares/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fraturas do Rádio/complicações , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ulna/diagnóstico por imagem , Ulna/lesões , Fraturas da Ulna/complicações , Adulto Jovem , Lesões no Cotovelo
20.
JAMA Ophthalmol ; 138(2): 119-126, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31804666

RESUMO

Importance: Artifacts can affect optical coherence tomographic angiography (OCTA) images and may be associated with misinterpretation of OCT scans in both clinical trials and clinical settings. Objectives: To identify the prevalence and type of artifacts in OCTA images associated with quantitative output and to analyze the role of proprietary quality indices in establishing image reliability. Design, Setting, and Participants: This cross-sectional study evaluated baseline OCTA images acquired in multicenter clinical trials and submitted to the Fundus Photograph Reading Center in Madison, Wisconsin, between January 1, 2016, and December 31, 2018. Images were captured using the 3 mm × 3 mm and/or 6 mm × 6 mm scan protocol with commercially available OCTA systems. Artifacts, including decentration, segmentation error, movement, blink, refraction shift, defocus, shadow, Z offset, tilt, and projection, were given a severity grade based on involvement of cross-sectional OCT and area of OCT grid affected. Main Outcomes and Measures: Prevalence and severity of OCTA artifacts and area under the receiver operating characteristic curve (AUC) of quality indices with image reliability. Results: A total of 406 OCTA images from 234 eyes were included in this study, of which 221 (54.4%) were 6 mm × 6 mm scans and 185 (45.6%) were 3 mm × 3 mm scans. At least 1 artifact was documented in 395 images (97.3%). Severe artifacts associated with the reliability of quantitative outputs were found in 217 images (53.5%). Shadow (26.9% [109 images]), defocus (20.9% [85 images]), and movement (16.0% [65 images]) were the 3 most prevalent artifacts. Prevalence of artifacts did not vary with the imaging system used or with the scan protocol; however, the type of artifacts varied. Commercially recommended quality index thresholds had an AUC of 0.80 to 0.83, sensitivity of 97% to 99%, and specificity of 37% to 41% for reliable images. Conclusions and Relevance: Findings from this study suggest that artifacts associated with quantitative outputs on commercially available OCTA devices are highly prevalent and that identifying common artifacts may require correlation with the angiogram and cross-sectional OCT scans. Knowledge of these artifacts and their implications for OCTA indices appears to be warranted for more accurate interpretation of OCTA images.


Assuntos
Angiofluoresceinografia , Tomografia de Coerência Óptica , Artefatos , Estudos Transversais , Humanos , Prevalência
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