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Manual Methods (manual + methods)
Selected AbstractsAutomated QT Measurement and Application to Detection of Moxifloxacin-Induced ChangesANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2009David W. Mortara Ph.D. Background: Concern for drug-induced QT prolongation has caused significant investment in QT measurement to safety-test new compounds. Manual methods are expensive and time-consuming. Reliable automatic methods would be highly desirable. Methods: Twelve-lead Holter recordings were annotated beat-to-beat by an automatic algorithm for global QRS onset and T offset. T offset was established from the time of peak T downslope plus a rate-dependent offset, analogous to the "tangent method," wherein T offset is determined by extrapolating the T downslope to an intersection with the baseline. Results and Conclusions: Variances of the beat-to-beat QT measurements were in the range 2.5,3.4 ms over three distinct databases, including a large heart failure database. Application to a moxifloxacin/placebo control database of 29 subjects showed excellent results. [source] Multicenter clinical experience with flow cytometric method for fetomaternal hemorrhage detectionCYTOMETRY, Issue 6 2002Jenn C. Chen Abstract BACKGROUND Enumeration of fetal red blood cells (RBCs) is important in the management of fetomaternal hemorrhage (FMH), particularly in situations of Rh incompatibility. METHODS We evaluated results from three institutions using the flow cytometric method (FCM) to detect fetal RBCs based on the anti-hemoglobin F (HbF) monoclonal antibody method. RESULTS During 1997,2001, 69 of 1,248 patients (5.5%) had measurable fetal erythrocytes (RBCs) in maternal blood. Only 21 patients (1.7%) had more than 30 mL of fetal blood detected in maternal blood. Of the 11 patients with large FMH and clinical follow-up, 7 had fetal demise (64%). In positive samples, significant differences were found in the fluorescence intensity (FI) of anti-HbF antibody staining between HbF-negative erythrocytes (HbF-) and adult HbF containing erythrocytes (F cells; 4 ± 0 versus 57 ± 9 linear mean channels [LMC]; P < 0.001) and between HbF-cells and fetal RBCs (4 ± 0 versus 433 ± 136 LMC; P < 0.001). In addition, significant differences were observed in forward light scatter intensity between HbF-cells and fetal RBCs (298 ± 15 versus 355 ± 68 LMC, P = 0.03). The transportability of the test is also addressed by comparing results from two other laboratories. The experience of our three laboratories, as well as the results from the recently reinitiated College of American Pathologists survey, which compares FCM and manual methods, clearly documents the superiority of the FCM test over the manual Kleihauer-Betke (KB) test. CONCLUSIONS The FCM is a simpler, more objective, and more precise alternative to the KB method in clinical testing. The high mortality rate associated with large FMH and therapeutic implications of these results should give laboratories motivation to abandon the KB method with more robust FCM to detect FMH. Cytometry (Clin. Cytometry) 50:285,290, 2002. © 2002 Wiley-Liss, Inc. [source] Antioxidant capacity of rapeseed meal and rapeseed oils enriched with meal extractEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2010Aleksandra Szyd, owska-Czerniak Abstract Response surface methodology (RSM) was used to evaluate the quantitative effects of two independent variables: solvent polarity and temperature of the extraction process on the antioxidant capacity (AC) and total phenolics content (TPC) in meal rapeseed extracts. The mean AC and TPC results for meal ranged between 1181,9974,µmol TE/100,g and 73.8,814,mg sinapic acid/100,g of meal. The experimental results of AC and TPC were close to the predicted values calculated from the polynomial response surface models equations (R2,=,0.9758 and 0.9603, respectively). The effect of solvent polarity on AC and TPC in the examined extracts was about 3.6 and 2.6 times greater, respectively, than the effect of processing temperature. The predicted optimum solvent polarity of ,,=,78.3 and 63.8, and temperature of 89.4 and 74.2°C resulted in an AC of 10,014,µmol TE/100,g and TPC of 863,mg SAE/100,g meal, respectively. The phenolic profile of rapeseed meal was determined by an HPLC method. The main phenolics in rapeseed meal were sinapine and sinapic acid. Refined rapeseed oils were fortified with an extract , rich in polyphenols , obtained from rapeseed meal. The supplemented rapeseed oil had higher AC and TPC than the refined oil without addition of meal extracts. However, AC and TPC in the enriched oils decreased during storage. The TPC in the studied meal extracts and rapeseed oils correlated significantly (p<0.0000001) positively with their AC (R2,=,0.9387). Practical applications: Many bioactive compounds extracted from rapeseed meal provide health benefits and have antioxidative properties. Therefore, it seems worth to consider the application of antioxidants extracted from the rapeseed meal for the production of rapeseed oils with potent AC. Moreover, antioxidants extracted from the rapeseed meal were added to refined rapeseed oil in order to enhance its AC. AC was then tested by FRAP assay. FRAP method is based on the reduction of the ferric tripyridyltriazine (Fe3+ -TPTZ) complex to the ferrous tripyridyltriazine (Fe2+ -TPTZ), and it is simple, fast, low cost, and robust method. FRAP method does not require specialized equipment and can be performed using automated, semi-automatic, or manual methods. Therefore the proposed FRAP method can be employed by the fat industry laboratories to asses the AC of rapeseed oils and meal. [source] Quantification of red blood cell fragmentation by the automated hematology analyzer XE-2100 in patients with living donor liver transplantationINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2005S. BANNO Summary The fragmented red cell (FRC) is a useful index for diagnosing and determining the severity of thrombotic thrombocytopenic purpura (TTP), thrombotic microangiopathy (TMA) and other similar conditions, as it is found in peripheral blood in patients with these diseases. The FRC expression rate has conventionally been determined by manual methods using smear samples. However, it is difficult to attain accurate quantification by such methods as they are time consuming and prone to a great margin of error. With cases of living donor liver transplantation, the current study examined the possibility of using a multi-parameter automated hematology analyzer, the XE-2100 (Sysmex Corporation) for FRC quantification. While there was a notable correlation between the manual and automated measurements, the manual measurement resulted in higher values. This suggested remarkable variations in judgment by individuals. The FRC values had a significant correlation with the reticulocyte count, red blood cell distribution width (RDW), fibrin/fibrinogen degradation products (P-FDP) and lactate dehydrogenase (LDH) among the test parameters, and this finding was consistent with the clinical progression in patients. The automated method can offer precise measurements in a short time without inter-observer differences, meeting the requirement for standardization. The determination of FRC count (%) by the XE-2100 that enables early diagnoses and monitoring of TTP or TMA will be useful in the clinical field. [source] 4332: Determination of corneal endothelial cell density in French eye banks: second lookACTA OPHTHALMOLOGICA, Issue 2010N DELESALLE Purpose Considering the importance of having a precise, robust and especially reproducible ECD counting method, Afssaps organized from April 2008 to June 2009 a second assessment of the reliability of the routine cell count within the 18 french Eye banks. Methods The study design was similar to the first assessment driven by the laboratory ,Biology, engineering and imaging of Corneal Graft' in 2003 (Transplantation 2004; 78: 1299-1302).5 test corneas (1 mm2 of flat mounted, fixed and alizarin stained human corneal endothelium) were selected and sent to the 18 Eye banks. All the usual technicians of each bank had to count the test corneas using the routine method(s) employed to assess grafts. Results 430 counts were carried out by 70 eye banks technicians, by manual and/or image analysis system. 42% (180/430) deviated by more than 10% from the expected ECD. Among them, 128 were over-estimated (max +88%) and 52 were under-estimated (max -31%). 2 banks constantly over-estimated (in the mean +31,7% and +42,7%, no calibration and/or material problem) but the 16 other banks were in average within ±13% from expected ECDs. For manual methods, a statistically significant difference between banks was observed for the 5 test corneas, whereas no difference was observed with image analyzers. ECD obtained with the analysers were closer to expected values than with the manual methods. Compared to the 2003 study, reliability of ECD determination globally improved. Conclusion Image analysis systems prove more reliable (precise and with a lower intra and inter observer variability) than manual counting methods. This ,second look' of Eye banks will allow editing recommendations to improve ECD determination. [source] | |||||||||||||