Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

On 20 consecutive work days during four weeks, one technologist performed 24 microchromatographic determinations of hemoglobin A2 (Hb A2) by each of four methods: the Efremov procedure requiring Tris/HCl buffer, the original Huisman technique with use of glycine developer, and two commercial test kits in which a modified glycine developer is used. The bloood samples tested were obtained from 12 adults with no hematological abnormality and from 12 beta-thalassemia carriers previously diagnosed by familial and hematologic studies. Results by the first method and the two commercial kits (one from Helena Laboratories and one from Isolab, Inc.) did not differ significantly in precision for either the normal or beta-thalassemia trait samples. For both sample types, the second method yielded larger coefficients of variation than those obtained with the other methods. Moreover, the second method was the only one with which values overlapped for normal samples and samples with above-normal Hb A2 concentrations.
 ...
PMID:Microchromatographic methods for hemoglobin A2 quantitation compared. 71 69

A new test for the laboratory diagnosis of spherocytosis, conventionally called 'Pink test', is presented. This test, semi-quantitatively or quantitatively, determines the hemolysis of small blood samples in a solution containing glycerol (135 mmol/l), NaCl (25 mmol/l), NaN3 (1.5 mmol/l), buffered to pH 6.66 with Bis-Tris (70 mmol/l) and HCl. 'Pink test', as well as 'acidified' glycerol lysis test, were positive in 100% of 42 patients suffering from hereditary spherocytosis, and optimally discriminated them from healthy subjects, showing a diagnostic sensitivity greater than 'standard' glycerol lysis test and osmotic fragility in hypotonic saline solutions of fresh or incubated blood. 'Pink test' was also positive in some cases of renal failure, immunohemolytic anemia, chronic hemoproliferative disorders, normal pregnant women, and negative in other microcytic anemias (beta-thalassemia, iron deficiency anemia). The results do not critically depend on pH of the solution (differently from those obtained with 'acidified' glycerol lysis test), and for this reason they show a good reproducibility.
 ...
PMID:A new test for the laboratory diagnosis of spherocytosis. 643 93

Commercial microcolumns introduced in 1976 by Helena Laboratories ("Hb A2 Quik Column") and by Isolab, Inc. ("Quik-Sep") provide a rapid, simple, accurate method for quantitation of hemoglobin A2 (Hb A2). However, these kits cannot be used for the quantitation of Hb A2 in the presence of slow-moving variants such as Hb S. Recently, Isolab, Inc., produced a new kit ("Quik-Sep Improved Hb A2 Test") for quantitation of both Hb A2 and Hb S. We compared results obtained with the new Isolab kit to results obtained with the original Tris/HCl method for quantitation of Hb A2 and Hb S. Blood was drawn from persons with sickle cell trait (A/S), sickle cell anemia (S/S), sickle cell/beta+ thalassemia (S/beta+ thal) and sickle cell/beta 0 thalassemia (S/beta 0 thal) and percentages of Hb A2 and Hb S were determined by each method. We found no significant differences in Hb A2 percentages by the two methods, and the coefficients of variation were similar. Both methods showed only slight overlap of Hb A2 values from subjects with some form of beta thalassemia and those with A/S or S/S. However, the Tris/HCl method consistently gave values for Hb S that were higher and closer to those expected, suggesting that the Isolab kit does not accurately quantitate Hb S.
 ...
PMID:Evaluation of a commercial kit for microchromatographic quantitation of hemoglobin A2 in the presence of hemoglobin S. 723 91

A flow injection (FI)-reduced volume column system was developed for hemoglobin (Hb) typing to be used as an initial screening method for thalassemia. The column was packed with 140 microl diethylaminoethyl (DEAE)-Sephadex A-50 ion exchange beads. Hb can be separated using Tris-HCl buffer solution with pH gradient 8.5-6.5 and then monitored spectrophotometrically at 415 nm. The hemolysate of 40 blood samples from packed red cells were screened for thalassemia by determining the amount of HbA(2) and HbE present. The proposed system was able to predict positive test results from those samples with beta, E-trait and EE homozygous thalassemia, Hb types that were independently identified following the conventional method at the hospital laboratory. Advantages of the proposed system over the conventional column technique include low amount of reagents and blood sample needed, short analysis time and low cost. Each analysis required only 80 microl of 50 times diluted packed cells, which is equivalent to 1.6 microl undiluted packed cells, and it can be completed in only 35 min. This simple FI-reduced volume column system was demonstrated to be an economic alternative system for Hb typing to initially screen some types of thalassemia such as beta-trait, E-trait and EE-homozygous which are commonly found in Thailand.
 ...
PMID:A simple flow injection-reduced volume column system for hemoglobin typing. 1896 42