scholarly journals Difference in hemoglobin %A2 between homozygous hemoglobin A and hemoglobin S-trait patients as measured by capillary electrophoresis

2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S32-S32
Author(s):  
C M Tucker ◽  
D Stickle
Keyword(s):  
Capillary Electrophoresis ◽  
High Performance ◽  
Glycated Hemoglobin ◽  
Hemoglobin S ◽  
Analytical Interference ◽  
Hemoglobin Variants ◽  
Variant Analysis ◽  
R Programming ◽  
Hemoglobin A2

Abstract Introduction/Objective Quantitation by high-performance liquid chromatography (HPLC) of hemoglobin %A2 is often not used in evaluation for thalassemia of hemoglobin S-trait patients, due to analytical interference from glycated hemoglobin S1d to increase %A2. In contrast, an increase in %A2 for S-trait when measured by capillary electrophoresis (CE) has been reported, without known analytical interference. This observation has not been re- evaluated in modern versions of CE, however. For validation exercises associated with startup of CE at our institution, we compared distributions of %A2 among A patients and S-trait patients using Sebia “Capillarys® 2” CE. Methods/Case Report %A2 is provided in two Sebia “Capillarys® 2” methods: analysis of A1c (method 1, M1) and analysis of hemoglobin variants (method 2, M2). To minimize effect of potential preselection for thalassemia among M2 samples, we first evaluated distributions of %A2 for A and S-trait among M1 samples. We then evaluated correlation of A2 measurements between M1 and M2. Statistical analyses were conducted using R programming. Results (if a Case Study enter NA) Using M1, %A2 for S-trait patients (2.61±0.31%, n=116) was higher than for A patients (2.11±0.27%, n=108) (p<0.001), with difference=0.42-0.57 %A2 (95% confidence interval, CI). %A2 by M1 was consistently less than %A2 by M2, for both A and S-trait (p>0.25): for A, M1/M2=0.89±0.05 (n=35); for S-trait, M1/M2=0.88±0.05 (n=32). Decreased %A2 by M1 compared to M2 may in part be due to separation in M1 of a glycated form of A2. Using M2, %A2 for S-trait patients (3.05±0.29%, n=32) was higher than for A patients (2.41±0.29%, n=35) (p<0.001), with difference=0.50-0.76 %A2 (CI). M2 results were consistent with M1 data when combined with the observed M1/M2 ratios. Conclusion Results suggest a physiological increase in %A2 in S-trait patients compared to A patients, not likely to be attributable to thalassemia. The average increase is ~0.6 %A2 for hemoglobin variant analysis by CE.

Screening for hemoglobinopathy with capillary electrophoresis in adult patients

2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S18-S18
Author(s):  
Bremansu Osa-Andrews ◽  
Nicole Desimone ◽  
Ravi Sarode ◽  
Sarita Paulino ◽  
Jing Cao
Keyword(s):  
Bone Marrow ◽  
Capillary Electrophoresis ◽  
Gel Electrophoresis ◽  
Screening Method ◽  
Adult Patients ◽  
Red Blood Cell Indices ◽  
Hemoglobin Variants ◽  
Clinically Significant ◽  
Hemoglobin A2 ◽  
Rule Out

Abstract Hemoglobinopathy screening is frequently needed in adult patients, including prenatal carrier screen, workup of unexplained anemia, and bone marrow donor and recipient screening. However, the preferred test method for screening of hemoglobinopathy is not well established due to limited guidance from professional societies. American College of Obstetricians and Gynecologists’ Committee on Genetics recommended hemoglobin electrophoresis as the screening method of hemoglobinopathy in pregnancy; nevertheless, electrophoresis employs various methodologies, including acid gel electrophoresis, alkaline gel electrophoresis, and capillary electrophoresis (CE) with alkaline buffer. For other adult patient populations who need hemoglobinopathy screening, no clear guidelines dictate the method of choice. A previous study has shown that CE captures major hemoglobinopathies with comparable performance to high-performance liquid chromatography (HPLC) in pediatric patients but no study has investigated using CE alone in adult patient screening. In this retrospective study, we evaluated the utility of CE as a screening method to rule out clinically significant hemoglobin variants. During eight months, 312 adult patients without previously identified hemoglobin variants had hemoglobinopathy screening performed using a comprehensive testing algorithm. This cascade algorithm screens for hemoglobinopathy using both CE (Capillarys, Sebia, Paris, France) and HPLC (laboratory-developed test) with reflex to more advanced variant identification such as mass spectrometry and genetic analyses. Categories of abnormal findings were reviewed to determine if hemoglobinopathy can be identified by using CE only. The patient population mainly consists of pregnant women and anemic patients with hematologic malignancies with an average age of 42. Out of the 312 screened patients, 47 had abnormal results. The most frequent condition was elevated hemoglobin F (N=25) ranging 2-5% seen in leukemia patients on chemotherapy attributed to bone marrow stress. Eight cases of beta plus thalassemia (featuring hemoglobin A2 >4%) and 3 cases of hemoglobin C trait were identified in patients with little to mild clinical manifestations (red blood cell indices suggesting anemia). Decreased hemoglobin A2 fraction was observed in 7 patients, and potential causes were alpha thalassemia or iron deficiency. Other less common hemoglobinopathies included heterozygote A2 prime (N=3, a benign delta chain variant that migrates separately from hemoglobin A2 on CE) and hemoglobin G-Philadelphia (N=1). All of the abnormal results are identifiable by CE alone, although HPLC and more advanced methods help confirm the diagnosis. Our study shows that CE as the first line of screening method would rule out major hemoglobinopathies in adults. There have been reports that rare but clinically significant hemoglobin variants like hemoglobin Malmo may not be detected by CE, and therefore, certain pre-test probability factors need to be considered when testing for hemoglobinopathies, such as race/ethnicity background, family history, red blood cell indices, and iron deficiency status.

Simple method for determination of A1c-type glycated hemoglobin(s) in rats using high performance liquid chromatography

1989 ◽  
Vol 21 (3) ◽  
pp. 211-221 ◽  
Author(s):  
Naoto Kondo ◽  
Yoji Shibayama ◽  
Yoshio Toyomaki ◽  
Masashi Yamamoto ◽  
Hiroyuki Ohara ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Glycated Hemoglobin ◽  
Simple Method ◽  
Hemoglobin S

scholarly journals False measurement of glycated hemoglobin in patients without hemoglobin A

2019 ◽  
Vol 39 (1) ◽  
Author(s):  
Minghuan Suo ◽  
Dongmei Wen ◽  
Weijia Wang ◽  
Decai Zhang ◽  
Shengnan Xu ◽  
...  
Keyword(s):  
Capillary Electrophoresis ◽  
Glycated Hemoglobin ◽  
Biochemical Marker ◽  
Compound Heterozygous ◽  
Test Results ◽  
Ion Exchange Hplc ◽  
Hemoglobin Variants ◽  
Hba1c Measurement ◽  
Compound Heterozygotes ◽  
Electrophoresis Technique

Abstract Background: Hemoglobin (Hb) A1c, a biochemical marker widely used in monitoring diabetes mellitus, can be quantitatively measured by various examining systems. However, significant errors still exist. In the present study, we evaluated the HbA1c level in five patients with compound heterozygotes by five different examining systems and our goal is to identify the existence of erroneous HbA1c measurement. Methods: Blood samples collected from normal (no hemoglobin variants) and abnormal (compound heterozygotes) patients were analyzed by capillary electrophoresis technique and sequence analysis. The samples without HbA expression via above methods were further analyzed for HbA1c by ion exchange HPLC Variant II/ Variant II Turbo 2.0 (VII and VII-T 2.0), boronate affinity HPLC, capillary electrophoresis, and Tinaquant immunoassay. Results: HbA1c expression were unexpectedly detected in the compound heterozygous samples by using additional examining systems: The HPLC VII and VII-T 2.0 detected HbA1c expression in two of five samples and failed to detect the abnormal HbA2 expression; the CE system detected HbA1c expression in one of five samples with abnormal HbA2 expression; the Ultra2 and PPI system detected the HbA1c expression of all samples without abnormal HbA2. Conclusions: Five human samples without HbA expression were additionally detected with HbA1c expression with or without abnormal HbA2 expression by five analysis systems and the different examining assay potentially affected the test results. These results demonstrated that the limitations of current examining systems for monitoring patients with hemoglobin disorders highlighting the further improvement in the method of clinical HbA examination.

THE USE OF CASE STUDY METHOD IN TEACHING THE TERMINOLOGY IN THE FIELD OF AGRICULTURAL MACHINERY

2019 ◽  
pp. 123-130
Keyword(s):  
Case Studies ◽  
High Performance ◽  
Mechanical Engineering ◽  
The United States ◽  
Machine Building ◽  
Soil Tillage ◽  
Case Study Method ◽  
Agricultural Machine ◽  
Manufacturing Machine

The scientific research works concerning the field of mechanical engineering such as, manufacturing machine slate, soil tillage, sowing and harvesting based on the requirements for the implementation of agrotechnical measures for the cultivation of plants in its transportation, through the development of mastering new types of high-performance and energy-saving machines in manufacturing machine slate, creation of multifunctional machines, allowing simultaneous soil cultivation, by means of several planting operations, integration of agricultural machine designs are taken into account in manufacturing of the local universal tractor designed basing on high ergonomic indicators. For this reason, this article explores the use of case studies in teaching agricultural terminology by means analyzing the researches in machine building. Case study method was firstly used in 1870 in Harvard University of Law School in the United States. Also in the article, we give the examples of agricultural machine-building terms, teaching terminology and case methods, case study process and case studies method itself. The research works in the field of mechanical engineering and the use of case studies in teaching terminology have also been analyzed. In addition, the requirements for the development of case study tasks are given in their practical didactic nature. We also give case study models that allow us analyzing and evaluating students' activities.

Sulphonamide: Distribution, Toxicology, Environmental Characteristics, and Analysis - A Review

2020 ◽  
Vol 16 ◽  
Author(s):  
Kirubanandam Grace Pavithra ◽  
Vasudevan Jaikumar ◽  
Ponnusamy Senthil Kumar ◽  
PanneerSelvam SundarRajan
Keyword(s):  
Aqueous Solution ◽  
High Performance Liquid Chromatography ◽  
Capillary Electrophoresis ◽  
Liquid Chromatography ◽  
High Performance ◽  
Uv Spectroscopy ◽  
Relevant Information ◽  
Fluorometric Determination ◽  
Distinctive Features ◽  
The World

Background: Many antibiotics were widely used as medication based on their distinctive features. Among them, sulphonamides were commonly used, however their recalcitrant nature makes them difficult to dispose. Hence, their interaction with environment and analytic technique requires considerable attention globally. Objective: Therefore, this review aimed to provide detailed discussion about environmental as well as human health behaviour and analytic techniques corresponding to sulphonamides. Methods: Various results and discussion were extracted from technical journals and books published by different researchers from all over the world. The cited bibliographic references were intentionally investigated in order to extract relevant information related to proposed work. Results: In this review, the determination techniques such as UV-spectroscopy, Enthalpimetry, Immunosensor, Chromatography, Chemiluminescence, Photoinduced fluorometric determination, Capillary electrophoresis for sulphonamide determination were discussed in detail. Among them, High performance liquid chromatography (HPLC) and UV-spectroscopy was effective and extensively used for screening sulphonamide. Conclusion: Knowing the quantification and behaviour of sulphonamide in aqueous solution is mandatory to opt the suitable wastewater treatment required. Hence, choosing appropriate high precision and feasible screening techniques is necessary, which can be attained with this review.

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