scholarly journals Performance of Fetal Cardiac Volume Derived from VOCAL (Virtual Organ Computer-Aided AnaLysis) in Predicting Hemoglobin (Hb) Bart’s Disease

2021 ◽  
Vol 10 (20) ◽  
pp. 4651
Author(s):  
Keooudone Thammavong ◽  
Suchaya Luewan ◽  
Theera Tongsong
Keyword(s):  
At Risk ◽  
High Performance ◽  
Peak Systolic Velocity ◽  
Cardiac Volume ◽  
Vocal Technique ◽  
Computer Aided Analysis ◽  
The Mean ◽  
Hb Bart's ◽  
Very High ◽  
Better Than

Objective: To determine the performance of fetal cardiac volume (CV) in the detection of fetal Hb Bart’s disease among fetuses at risk at 18–22 weeks of gestation and to compare the performance with those of cardiothoracic diameter ratio (CTR) and middle cerebral artery peak systolic velocity (MCA-PSV). Methods: Fetuses at risk of Hb Bart’s disease between 18 and 22 weeks of gestation prospectively underwent echocardiography with acquisition of the volume datasets (VDS) of fetal heart, using 4D-cardiac STIC. Subsequently, off-line analysis was blindly performed to measure cardiac volume using the VOCAL technique. Results: A total of 502 fetuses at risk meeting the inclusion criteria were included in the analysis, consisting of 117 (23.3%) fetuses with Hb Bart’s disease and 385 (76.7%) unaffected fetuses. The mean (±SD) gestational age at the time of ultrasound examination was 19.70 ± 1.3 weeks. In predicting fetal Hb Bart’s disease, CV, using a cut-off Z-score of 1.7, had a sensitivity of 94.9% and specificity of 94.0%. The performance of CV was slightly better than that of CTR but very superior to that of MCA-PSV (areas under curve: 0.988, 0.974 and 0.862, respectively). Conclusions: Fetal CV has a very high performance in predicting fetal Hb Bart’s disease at mid-pregnancy, comparable with CTR and much better than MCA-PSV.

Fetal Hemodynamic Response to Anemia in Early Gestation: Using Hemoglobin Bart’s Disease as a Study Model

2021 ◽  
Author(s):  
Suchaya Luewan ◽  
Fuanglada Tongprasert ◽  
Kasemsri Srisupundit ◽  
Kuntharee Traisrisilp ◽  
Phudit Jatavan ◽  
...  
Keyword(s):  
At Risk ◽  
Peak Systolic Velocity ◽  
Invasive Procedure ◽  
Doppler Velocity ◽  
Early Gestation ◽  
Volume Load ◽  
Sphericity Index ◽  
The Right ◽  
A Prospective Study ◽  
Hb Bart's

Abstract Objective To assess fetal hemodynamic changes in response to anemia in early gestation, using fetal Hb Bart’s disease as a study model. Methods A prospective study was conducted on pregnancies at risk for fetal Hb Bart’s disease at 12–14 weeks of gestation. Fetal hemodynamics were comprehensively assessed by 2D ultrasound, Doppler velocity, and cardio-STIC just prior to the invasive procedure for diagnosis. The various hemodynamic parameters of the affected and unaffected fetuses were compared. Results Of 56 fetuses at risk, 17 had Hb Bart’s disease and 39 were unaffected. The right and combined ventricular cardiac outputs (CO) were significantly higher in the affected fetuses (0.993 vs. 1.358; p < 0.001 and 1.010 vs. 1.236; p < 0.001, respectively), whereas the left CO tended to be higher but not significantly (1.027 vs. 1.113; p = 0.058). Cardiac dimensions, middle-cerebral artery peak systolic velocity, Tei index, and isovolemic contraction time were significantly increased, while the global sphericity index was significantly decreased. Interestingly, cardiac preload, ventricular wall thickness, shortening fraction, isovolemic relaxation time, and fetal heart rate were unchanged. Four fetuses had hydropic changes, but all cardiac functions were normal. Conclusion Fetal anemia induces hypervolemia and increases cardiac output to meet the tissue oxygen requirement, resulting in an increase in size without hypertrophy, volume load without pressure load, and a decrease in the globular sphericity index. The heart works very well but works harder, especially systolic ventricular load. Hydrops fetalis due to anemia appears not to be caused by heart failure as previously believed but rather by volume load with high vascular permeability at least in early pregnancy.

Comparison of the Performances of Middle Cerebral Artery Peak Systolic Velocity and Cardiothoracic Diameter Ratio in Predicting Fetal Anemia: Using Fetal Hemoglobin Bart’s Disease as a Study Model

2021 ◽  
pp. 1-8
Author(s):  
Wisit Chankhunaphas ◽  
Theera Tongsong ◽  
Fuanglada Tongprasert ◽  
Kasemsri Srisupundit ◽  
Suchaya Luewan ◽  
...  
Keyword(s):  
At Risk ◽  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Gestational Age ◽  
Peak Systolic Velocity ◽  
Fetal Hemoglobin ◽  
Diameter Ratio ◽  
Fetal Anemia ◽  
Receiver Operating Characteristic Curves ◽  
Hb Bart's

<b><i>Objective:</i></b> The aim of the study was to compare the performances of cardiothoracic diameter ratio (CTR) and middle cerebral artery peak systolic velocity (MCA-PSV) in predicting fetal hemoglobin (Hb) Bart’s disease and identify the best CTR cut-off for each gestational period. <b><i>Methods:</i></b> Pregnancies at risk of fetal Hb Bart’s disease (gestational ages of 12–36 weeks) were prospectively recruited to undergo ultrasound examination. The measurements of CTR and MCA-PSV were performed and recorded before invasive diagnosis. <b><i>Results:</i></b> During the study period (2005–2019), a total of 1,717 pregnancies at risk of fetal Hb Bart’s disease met the inclusion criteria and were available for analysis, including 329 (19.2%) fetuses with Hb Bart’s disease. The mean gestational age at the time of diagnosis was 19.30 ± 5.6 weeks, ranging from 12 to 36 weeks. The overall performance of CTR <i>Z</i>-scores is superior to that of MCA-PSV multiple of median (MoM) values; area under curve of 0.866 versus 0.711, <i>p</i> value &#x3c;0.001. The diagnostic indices of CTR and MCA-PSV are increased with gestational age. Based on receiver operating characteristic curves of CTR <i>Z</i>-scores, the best cut-off points of CTR at 12–14, 15–17, 18–20, 21–23, and ≥24 weeks are 0.48, 0.49, 0.50, 0.51, and 0.54, respectively. The best cut-off of MCA-PSV is 1.3 MoM, giving the best performance at 21–23 weeks with a sensitivity of 91.8% and specificity of 85.5%. <b><i>Conclusion:</i></b> The performance of CTR is much better than MCA-PSV in predicting fetal anemia caused by Hb Bart’s disease. Nevertheless, whether this can be reproduced in anemia due to other causes, like isoimmunization, is yet to be explored.

Appearance of Abnormal Cardiothoracic Ratio of Fetuses with Hemoglobin Bart’s Disease: Life Table Analysis

2017 ◽  
Vol 38 (05) ◽  
pp. 544-548 ◽  
Author(s):  
Chanane Wanapirak ◽  
Supatra Sirichotiyakul ◽  
Suchaya Luewan ◽  
Kasemsri Srisupundit ◽  
Fuanglada Tongprasert ◽  
...  
Keyword(s):  
At Risk ◽  
Life Table ◽  
Peak Systolic Velocity ◽  
First Trimester ◽  
Life Table Analysis ◽  
Prospective Longitudinal Study ◽  
Cardiothoracic Ratio ◽  
Table Analysis ◽  
Prospective Longitudinal ◽  
Hb Bart's

Abstract Objective To determine the timeline of the first appearance of an increased CT ratio of fetuses with hemoglobin (Hb) Bart’s disease. Materials and Methods A prospective longitudinal study was conducted on pregnancies at risk for fetal Hb Bart’s disease. Sonographic markers including cardiothoracic (CT) ratio and middle cerebral artery peak systolic velocity (MCA-PSV) were serially assessed and recorded from the first trimester. The definite diagnosis of fetal Hb Bart’s disease based on DNA analysis (CVS), or fetal Hb typing (HPLC; cordocentesis) was performed at the first appearance of an increased CT ratio. Results Of 275 pregnancies at risk, 64 fetuses were finally proven to be affected and life table analysis was performed. Most affected fetuses showed an increased CT ratio in late first trimester and early second trimester, with median time of the first appearance at 13 weeks and all affected fetuses were detected at 23 weeks or less. The CT ratio yielded a sensitivity of 100 % at a gestational age of 23 weeks with a false-positive rate of 8 %. MCA-PSV appeared later than CT ratio. Only 9.4 % of affected cases developed abnormal MCA-PSV before an increased CT ratio. Conclusion The timeline of the first appearance of an increased CT ratio of fetuses with Hb Bart’s disease was established. This may help us identify Hb Bart’s disease among fetuses at risk in earlier gestation and proper schedules for serial ultrasound could be made more effectively.

scholarly journals Short-time measurements of interception in mountain spruce forest

2010 ◽  
Vol 58 (4) ◽  
pp. 213-220
Author(s):  
Ladislav Holko
Keyword(s):  
Spruce Forest ◽  
Open Area ◽  
Time Data ◽  
Rainfall Events ◽  
Mean Values ◽  
Rainfall Depth ◽  
The Mean ◽  
Short Time ◽  
Very High ◽  
Better Than

Short-time measurements of interception in mountain spruce forestOpen area rainfall and throughfall measurements in the Western Tatra Mountains (altitude about 1500 m a.s.l.) made by tipping bucket gauges were used to estimate the usefulness of the short-time data in analysis of spruce interception. The 10-minute data from period 13 May-13 October 2009 did not reveal meaningful correlations between the open area rainfall and throughfall. Aggregated measurements representing individual rainfall events were more useful. They showed linear relationship between open area rainfall and throughfall for events with total rainfall depth in the open area exceeding 5 mm. Correlation between open area rainfall and throughfall for rainfall events with duration above 120 minutes was significantly better than for the shorter ones. Mean values of interception (percentage of open area rainfall which did not appear in throughfall) of individual rainfall events was high. When we excluded events for which throughfall was higher than the open area rainfall, mean interception for larger and longer rainfall events was 46% and 48%, respectively. For smaller (runoff depth below 5 mm) and shorter events (duration below 2 hours) the mean interception was 70% and 72%, respectively. However, the data revealed very high variability of interception.

Advances in imaging SIMS studies of stained and BrdU-labelled human metaphase chromosomes

1995 ◽  
Vol 53 ◽  
pp. 932-933
Author(s):  
R. Levi-Setti ◽  
J. M. Chabala ◽  
R. Espinosa ◽  
M. M. Le Beau
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Analytical Sensitivity ◽  
Metaphase Chromosomes ◽  
Banding Patterns ◽  
Sector Mass Spectrometer ◽  
Staining Methods ◽  
The University ◽  
Secondary Ion ◽  
Better Than

We have shown previously that isotope-labelled nucleotides in human metaphase chromosomes can be detected and mapped by imaging secondary ion mass spectrometry (SIMS), using the University of Chicago high resolution scanning ion microprobe (UC SIM). These early studies, conducted with BrdU- and 14C-thymidine-labelled chromosomes via detection of the Br and 28CN- (14C14N-> labelcarrying signals, provided some evidence for the condensation of the label into banding patterns along the chromatids (SIMS bands) reminiscent of the well known Q- and G-bands obtained by conventional staining methods for optical microscopy. The potential of this technique has been greatly enhanced by the recent upgrade of the UC SIM, now coupled to a high performance magnetic sector mass spectrometer in lieu of the previous RF quadrupole mass filter. The high transmission of the new spectrometer improves the SIMS analytical sensitivity of the microprobe better than a hundredfold, overcoming most of the previous imaging limitations resulting from low count statistics.

Discriminant Validation of the Test of Reading Performance (TORP) for Identifying Children at Risk of Reading Difficulties

2000 ◽  
Vol 16 (2) ◽  
pp. 139-146 ◽  
Author(s):  
Padeliadu Susana ◽  
Georgios D. Sideridis
Keyword(s):  
At Risk ◽  
Elementary School Students ◽  
Reading Difficulties ◽  
Reading Performance ◽  
Low Achievers ◽  
Children At Risk ◽  
School Students ◽  
Students At Risk ◽  
Group A ◽  
The Mean

Abstract This study investigated the discriminant validation of the Test of Reading Performance (TORP), a new scale designed to evaluate the reading performance of elementary-school students. The sample consisted of 181 elementary-school students drawn from public elementary schools in northern Greece using stratified random procedures. The TORP was hypothesized to measure six constructs, namely: “letter knowledge,” “phoneme blending,” “word identification,” “syntax,” “morphology,” and “passage comprehension.” Using standard deviations (SD) from the mean, three groups of students were formed as follows: A group of low achievers in reading (N = 9) including students who scored between -1 and -1.5 SD from the mean of the group. A group of students at risk of reading difficulties (N = 6) including students who scored between -1.5 and -2 SDs below the mean of the group. A group of students at risk of serious reading difficulties (N = 6) including students who scored -2 or more SDs below the mean of the group. The rest of the students (no risk, N = 122) comprised the fourth group. Using discriminant analyses it was evaluated how well the linear combination of the 15 variables that comprised the TORP could discriminate students of different reading ability. Results indicated that correct classification rates for low achievers, those at risk for reading problems, those at risk of serious reading problems, and the no-risk group were 89%, 100%, 83%, and 97%, respectively. Evidence for partial validation of the TORP was provided through the use of confirmatory factor analysis and indices of sensitivity and specificity. It is concluded that the TORP can be ut ilized for the identification of children at risk for low achievement in reading. Analysis of the misclassified cases indicated that increased variability might have been responsible for the existing misclassification. More research is needed to determine the discriminant validation of TORP with samples of children with specific reading disabilities.

Monoamine Oxidase and Other Mitochondrial Enzymes in Density Subpopulations of Human Platelets

1988 ◽  
Vol 59 (01) ◽  
pp. 029-033 ◽  
Author(s):  
K G Chamberlain ◽  
D G Penington
Keyword(s):  
Monoamine Oxidase ◽  
Protein Concentration ◽  
Close Correlation ◽  
Human Platelets ◽  
Mitochondrial Enzymes ◽  
Density Fractions ◽  
Percoll Gradients ◽  
Normal Human ◽  
The Mean ◽  
Very High

SummaryNormal human platelets have been separated according to density on continuous Percoll gradients and the platelet distribution divided into five fractions containing approximately equal numbers of platelets. The mean volumes and protein contents of the platelets in each fraction were found to correlate positively with density while the protein concentration did not differ significantly between the fractions. Four mitochondrial enzymes (monoamine oxidase, glutamate dehydrogenase, cytochrome oxidase and NADP-dependent isocitrate dehydrogenase) were assayed and their activities per unit volume were found to increase in a very similar monotonie fashion with platelet density. When MAO and GDH were assayed on the same set of density fractions the correlation between the two activities was very high (r = 0.94–1.00, p <0.001) and a similar close correlation was found between MAO and ICDH. The results support the hypothesis that high density platelets either have a higher concentration of mitochondria or have larger mitochondria than low density platelets.

Placental Transfer of Vitamin K1 and Its Implications in Fetal Hemostasis

1988 ◽  
Vol 60 (01) ◽  
pp. 039-043 ◽  
Author(s):  
L Mandelbrot ◽  
M Guillaumont ◽  
M Leclercq ◽  
J J Lefrère ◽  
D Gozin ◽  
...  
Keyword(s):  
Vitamin K ◽  
High Performance ◽  
Ultrasound Guidance ◽  
Placental Transfer ◽  
Vitamin K1 ◽  
Vitamin K Deficiency ◽  
Prothrombin Activity ◽  
Oral Supplementation ◽  
K Deficiency ◽  
The Mean

SummaryVitamin K status was evaluated using coagulation studies and/ or vitamin IQ assays in a total of 53 normal fetuses and 47 neonates. Second trimester fetal blood samples were obtained for prenatal diagnosis under ultrasound guidance. Endogenous vitamin K1 concentrations (determined by high performance liquid chromatography) were substantially lower than maternal levels. The mean maternal-fetal gradient was 14-fold at mid trimester and 18-fold at birth. Despite low vitamin K levels, descarboxy prothrombin, detected by a staphylocoagulase assay, was elevated in only a single fetus and a single neonate.After maternal oral supplementation with vitamin K1, cord vitamin K1 levels were boosted 30-fold at mid trimester and 60 fold at term, demonstrating placental transfer. However, these levels were substantially lower than corresponding supplemented maternal levels. Despite elevated vitamin K1 concentrations, supplemented fetuses and neonates showed no increase in total or coagulant prothrombin activity. These results suggest that the low prothrombin levels found during intrauterine life are not due to vitamin K deficiency.

KEMPER C688

Alloy Digest ◽  
2017 ◽  
Vol 66 (12) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Copper Alloy ◽  
High Performance ◽  
High Conductivity ◽  
Bend Strength ◽  
Very High

Abstract Alloy C688 is a high-performance copper alloy with very high conductivity. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as forming and joining. Filing Code: Cu-867. Producer or source: Gebr. Kemper GmbH + Company KG Metallwerke.

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