IC-P1-022: High specificity in automated computer classification of probable AD using multi-site ADNI MRI

ABSTRACTSerological testing to detect toxoplasmosis is of major importance to avoid the possible effects of the disease in newborns. This study assessed anti-ToxoplasmaIgG and IgM with the Vidas (bioMérieux), Architect (Abbott), and Liaison (DiaSorin) systems in 631 sera from pregnant women and newborns as well as anti-ToxoplasmaIgG avidity with these three systems on 54 sera from pregnant women with positive IgG and IgM. The IgG and IgM results were in agreement in, respectively, 95.2% and 98.3% (Vidas versus Architect) and 96.9% and 95.3% (Vidas versus Liaison) of the samples. Specificities were excellent for all the assays, while Vidas sensitivities ranged (depending on the classification of gray zone results) from 93.8 to 98.4% for IgG (Architect, 84.4 to 93.8%; Liaison, 93.8%) and from 81.8 to 90.9% for IgM (Architect, 63.6%; Liaison, 81.8 to 90.9%). In seroconversion sequences, IgMs were generally detected simultaneously by the three assays, while Architect was the earliest assay to detect IgG. In noninfected children, maternally transmitted IgGs were detected for a longer time with Architect than with the other systems. IgMs were positive in only one infected child with the Vidas and Liaison systems. Significantly more sera were classified in the high-avidity category with Vidas than with Architect. This evaluation shows similar performances for Vidas and more recent systems. The Vidas system adequately detects toxoplasmosis in pregnant women and newborns. This system fits the needs of laboratories working on small routine series for first-line testing as well as expert laboratories, due to a high specificity and a powerful avidity test.

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Computer Classification of Roots from Digitized Video Images

HortScience ◽

10.21273/hortsci.30.4.906e ◽

1995 ◽

Vol 30 (4) ◽

pp. 906E-906 ◽

Cited By ~ 1

Author(s):

Gary W. Stutte ◽

Elizabeth C. Stryjewski

Keyword(s):

Root Length ◽

Space Shuttle ◽

Root Systems ◽

Image Capture ◽

Pixel Intensity ◽

Nih Image ◽

Video Images ◽

Computer Classification ◽

Manual Methods

Manual methods for estimating root length are tedious and time-consuming. Image capture and analysis systems can be used to obtain precise measurements of root length and growth angle. Root activity can also be determined through analysis of the mean pixel intensity of a digitized image. Both commercial (the IBM-compatible ICAS System) and public domain (the Macintosh-based NIH Image) image capture and analysis software have been used to analyze intact root systems. Examples of ICAS classification of hydroponic and soil-grown root systems will be presented. Advantages of the NIH Image software for analysis of micro-gravity experiments aboard the Space Shuttle will be discussed.

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Criteria for defining interictal epileptiform discharges in EEG

Neurology ◽

10.1212/wnl.0000000000009439 ◽

2020 ◽

Vol 94 (20) ◽

pp. e2139-e2147 ◽

Cited By ~ 4

Author(s):

Mustafa Aykut Kural ◽

Lene Duez ◽

Vibeke Sejer Hansen ◽

Pål G. Larsson ◽

Stefan Rampp ◽

...

Keyword(s):

Clinical Neurophysiology ◽

High Specificity ◽

Class Iii ◽

Clinical Implementation ◽

Accurate Identification ◽

Epileptiform Discharges ◽

Interictal Epileptiform Discharges ◽

Space Method ◽

Video Eeg

ObjectiveTo define and validate criteria for accurate identification of EEG interictal epileptiform discharges (IEDs) using (1) the 6 sensor space criteria proposed by the International Federation of Clinical Neurophysiology (IFCN) and (2) a novel source space method. Criteria yielding high specificity are needed because EEG over-reading is a common cause of epilepsy misdiagnosis.MethodsSeven raters reviewed EEG sharp transients from 100 patients with and without epilepsy (diagnosed definitively by video-EEG recording of habitual events). Raters reviewed the transients, randomized, and classified them as epileptiform or nonepileptiform in 3 separate rounds: in 2, EEG was reviewed in sensor space (scoring the presence/absence of each IFCN criterion for each transient or classifying unrestricted by criteria [expert scoring]); in the other, review and classification were performed in source space.ResultsCutoff values of 4 and 5 criteria in sensor space and analysis in source space provided high accuracy (91%, 88%, and 90%, respectively), similar to expert scoring (92%). Two methods had specificity exceeding the desired threshold of 95%: using 5 IFCN criteria as cutoff and analysis in source space (both 95.65%); the sensitivity of these methods was 81.48% and 85.19%, respectively.ConclusionsThe presence of 5 IFCN criteria in sensor space and analysis in source space are optimal for clinical implementation. By extracting these objective features, diagnostic accuracy similar to expert scorings is achieved.Classification of evidenceThis study provides Class III evidence that IFCN criteria in sensor space and analysis in source space have high specificity (>95%) and sensitivity (81%–85%) for identification of IEDs.

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Information Features for the Computer Classification of Pollen Grains

Intellekt Sist Proizv ◽

10.22213/2410-9304-2018-2-105-112 ◽

2018 ◽

Vol 16 (2) ◽

pp. 105

Author(s):

Yu B Kamalova ◽

G V Lomaev

Keyword(s):

Pollen Grains ◽

Computer Classification

В статье рассмотрены информационные признаки для компьютерной классификации пыльцевых зерен, а также проанализировано их морфологическое строение с рассмотрением геометрических признаков на разных уровнях. В качестве признаков для распознавания выявлены размеры (экваториальный диаметр и полярный радиус и др.), очертания, скульптура, апертура, текстура, полярность пыльцевых зерен. Приведен пример классификации пыльцевых зерен. Были найдены интервалы и количество растений, попадающих в данные интервалы по признакам, - экваториальному диаметру и полярному радиусу. Для экваториального диаметра было выявлено, что максимальное число растений (25 шт.) лежит в диапазоне от 40 до 50 мкм и т. д. По выявленным данным была построена таблица диапазонов экваториального диаметра и количества растений, попадающих в данный диапазон, и диаграмма. Было выявлено, что в диапазон значений полярного радиуса от 0 до 10 мкм не попало ни одного растения, в диапазон от 10 до 20 мкм попало 6 растений, от 20 до 30 мкм - 28 растений и т. д. По выявленным данным была построена таблица диапазонов полярного радиуса и количества растений, попадающих в данный диапазон, и диаграмма.

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Structural Basis for Different Substrate Specificities of Two ADP-Ribose Pyrophosphatases from Thermus thermophilus HB8

Journal of Bacteriology ◽

10.1128/jb.01522-07 ◽

2007 ◽

Vol 190 (3) ◽

pp. 1108-1117 ◽

Cited By ~ 13

Author(s):

Taisuke Wakamatsu ◽

Noriko Nakagawa ◽

Seiki Kuramitsu ◽

Ryoji Masui

Keyword(s):

Crystal Structure ◽

Flavin Adenine Dinucleotide ◽

Thermus Thermophilus ◽

High Specificity ◽

Ternary Complexes ◽

Structural Basis ◽

Water Molecules ◽

Substrate Specificities ◽

Catalytic Mechanisms

ABSTRACT ADP-ribose (ADPR) is one of the main substrates of Nudix proteins. Among the eight Nudix proteins of Thermus thermophilus HB8, we previously determined the crystal structure of Ndx4, an ADPR pyrophosphatase (ADPRase). In this study we show that Ndx2 of T. thermophilus also preferentially hydrolyzes ADPR and flavin adenine dinucleotide and have determined its crystal structure. We have determined the structures of Ndx2 alone and in complex with Mg2+, with Mg2+ and AMP, and with Mg2+ and a nonhydrolyzable ADPR analogue. Although Ndx2 recognizes the AMP moiety in a manner similar to those for other ADPRases, it recognizes the terminal ribose in a distinct manner. The residues responsible for the recognition of the substrate in Ndx2 are not conserved among ADPRases. This may reflect the diversity in substrate specificity among ADPRases. Based on these results, we propose the classification of ADPRases into two types: ADPRase-I enzymes, which exhibit high specificity for ADPR; and ADPRase-II enzymes, which exhibit low specificity for ADPR. In the active site of the ternary complexes, three Mg2+ ions are coordinated to the side chains of conserved glutamate residues and water molecules. Substitution of Glu90 and Glu94 with glutamine suggests that these residues are essential for catalysis. These results suggest that ADPRase-I and ADPRase-II enzymes have nearly identical catalytic mechanisms but different mechanisms of substrate recognition.

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