Evaluation of a Gilford "Automatic Enzyme Analyzer" Modified to Assay 60 Samples per Hour

1974 ◽  
Vol 20 (10) ◽  
pp. 1295-1304 ◽  
Author(s):  
Samuel A Morell ◽  
Daniel A Bach ◽  
Valborg E Ayers

Abstract A Gilford 3400 Automatic Enzyme Analyzer has been modified to assay 60 samples per hour in modes 1 and 2 (28 and 61 seconds of incubation) or 30 samples per hour in mode 3 (187 seconds of incubation). The calculation cycle was reduced threefold to print activity based on ΔA/20 s, rather than ΔA/60 s. Linear ranges at 30 and 37 °C for lactate dehydrogenase, aspartate aminotransferase, and alkaline phosphatase were determined with control sera at rates of 60 samples per hour and for creatine kinase activated by dithiothreitol at 30 samples per hour. AutoAnalyzer end-point assays of patients' sera were correlated with the Gilford U/liter values. Application of the Micromedic pipette to the Gilford AEA system provided a convenient mean to study the linear range, precision, and accuracy of an enzyme assay.

1973 ◽  
Vol 19 (9) ◽  
pp. 1079-1080
Author(s):  
Ted W Fendley ◽  
Jane M Hochholzer ◽  
Christopher S Frings

Abstract We have evaluated the effect of diluting serum with water or NaCl solution (8.5 or 9.0 g/liter) before assaying by a manual method for creatine kinase (EC 2.7.3.2), alkaline phosphatase (EC 3.1.3.1), lactate dehydrogenase (EC 1.1.1.27), and aspartate aminotransferase (EC 2.6.1.1) activity. The t test and the F test show no significant difference in the accuracy and precision of the assays at the 95% confidence level when 100 different samples were compared for each enzyme activity after use of the three diluents.


Author(s):  
R T P Jansen ◽  
A P Jansen

In a trial of the Netherlands coupled external/internal quality control program a control serum and an enzyme standard were analysed over a period of eight weeks, five times each week. Five enzymes were determined: alkaline phosphatase, creatine kinase, lactate dehydrogenase, alanine aminotransferase, and γ-glutamyltransferase. The measured values in the serum were converted to the standards. Those laboratories using the recommended methods also submitted their non-transformed serum values. The following standardisation techniques have been compared: ( a) no standardisation of methodology but use of enzyme standards; ( b) standardisation of methodology; ( c) standardisation of methodology combined with use of an enzyme standard. Results were submitted to analysis of variance. Standardisation of methodology did not yield smaller interlaboratory variation than the standardisation with enzyme standards. In this trial a combination of both standardisation techniques yielded generally better results. Results for γ-glutamyltransferase indicate that standardisation of substrate may be necessary apart from the use of an enzyme standard. The preparation of stable enzyme standards is stressed.


1975 ◽  
Vol 21 (1) ◽  
pp. 154-155
Author(s):  
Ted W Fendley ◽  
Christopher S Frings

Abstract In assays of creatine kinase (EC 2.7.3.2), alkaline phosphatase (EC 3.1.3.1), lactate dehydrogenase (EC 1.1.1.27), or asparate aminotransferase (EC 2.6.1.1) activities by certain end-point methods, we found no significant difference in the accuracy and precision of the results when serum was diluted with heat-inactivated pooled serum or NaCl solution (8.5 g/liter). For creatine kinase, asparate aminotransferase, and alkaline phosphatase, correlations were good for the two diluents, but poor in the case of lactate dehydrogenase.


1986 ◽  
Vol 32 (10) ◽  
pp. 1901-1905 ◽  
Author(s):  
J C Koedam ◽  
G M Steentjes ◽  
S Buitenhuis ◽  
E Schmidt ◽  
R Klauke

Abstract We produced three batches of a human-serum-based enzyme reference material (ERM) enriched with human aspartate aminotransferase (EC 2.6.1.1), alanine aminotransferase (EC 2.6.1.2), creatine kinase (EC 2.7.3.2), and lactate dehydrogenase (EC 1.1.1.27). The added enzymes were not exhaustively purified; thus the final ERMs contained some enzymes as contaminants, of which only glutamate dehydrogenase activity might interfere. The stability during storage and after reconstitution was good. The commutability of the four enzymes in the three ERM batches was also good, except when German or Scandinavian methods for aminotransferases were involved. The temperature-conversion factors for the ERMs were equivalent to those for patients' sera. Reactivation after reconstitution was complete within 5 min and was independent of the temperature of the reconstitution fluid. We believe that these secondary ERMs will aid in the transfer of accuracy between well-defined reference methods and daily working methods so that clinical enzymology results will become more comparable from laboratory to laboratory.


1987 ◽  
Vol 21 (1) ◽  
pp. 60-67 ◽  
Author(s):  
C. W. Davy ◽  
P. N. Trennery ◽  
J. G. Edmunds ◽  
J. F. B. Altman ◽  
D. A. Eichler

An investigation of raised plasma aspartate aminotransferase (AST) in marmosets after intramuscular ketamine injection suggested a local myotoxicity. This was confirmed by a range of histopathological findings from myofibrillar striation loss to necrosis. In addition to the elevations in AST levels, creatine kinase and the lactate dehydrogenase-5 isoenzyme levels were elevated. It was further demonstrated that, although the physical properties of the injectable solution (pH, osmolality) and to a lesser extent the injection procedure itself caused slight changes in plasma enzyme levels, the ketamine was predominantly responsible for the lesion. No hepatic interactions were seen. This effect should be taken into consideration when this anaesthetic is used in the marmoset if the primary objectives of the experiment entail routine blood analyses.


Author(s):  
Anna Nowakowska ◽  
Dorota Kostrzewa-Nowak ◽  
Rafał Buryta ◽  
Robert Nowak

Physical exercise strongly affects human metabolism and causes biochemical changes. This study aimed to investigate the relationship between routine plasma biomarker levels and recovery efficiency in soccer players during an entire competitive match season. The players participating in the study were divided into a midfielder/defender group (seven midfielders and seven defenders) and a goalie/substitute group (six persons—goalkeepers and players with a short cumulative match-time). The fasting capillary blood samples were taken 17–24 h after each competitive match. The blood plasma was used to determine the creatinine, urea, alkaline phosphatase, creatine kinase, lactate dehydrogenase, aspartate and alanine aminotransferase, iron and magnesium levels of the athletes. The levels of (AST) (aspartate aminotransferase), (ALT) (alanine aminotransferase) and (Cr) creatinine were higher in the midfielder/defender group than in the control group, but only AST and Cr significantly varied over time (AST decreased, and Cr increased with time). The (LDH) (lactate dehydrogenase) activity and urea level were significantly lower in the midfielder/defender group than in the goalie/substitute group, and it significantly varied over time (LDH decreased, and urea increased with time). No differences in the (CK) creatine kinase and (ALP) alkaline phosphatase activities between the groups was found, although CK increased significantly with time in the midfielder/defender group (particularly midfielders in the spring round). In midfielders, the AST activity and the iron level were significantly lower in the spring than in the autumn round. On the contrary, ALT, CK, urea and magnesium levels were significantly higher in the spring than in autumn round. A long-term measurement of biochemical parameters in elite soccer players indicated that AST, CK, LDH and creatinine levels, when analyzed together, could constitute a useful set of markers for monitoring recovery periods.


1986 ◽  
Vol 32 (1) ◽  
pp. 165-169
Author(s):  
G C Moses ◽  
G O Lightle ◽  
J F Tuckerman ◽  
A R Henderson

Abstract We evaluated the analytical performance of the EPOS (Eppendorf Patient Oriented System) Automated Selective Chemistry Analyzer, using the following tests for serum analytes: alanine and aspartate aminotransferases, lactate dehydrogenase, creatine kinase, gamma-glutamyltransferase, alkaline phosphatase, and glucose. Results from the EPOS correlated well with those from comparison instruments (r greater than or equal to 0.990). Precision and linearity limits were excellent for all tests; linearity of the optical and pipetting systems was satisfactory. Reagent carryover was negligible. Sample-to-sample carryover was less than 1% for all tests, but only lactate dehydrogenase was less than the manufacturer's specified 0.5%. Volumes aspirated and dispensed by the sample and reagent II pipetting systems differed significantly from preset values, especially at lower settings; the reagent I system was satisfactory at all volumes tested. Minimal daily maintenance and an external data-reduction system make the EPOS a practical alternative to other bench-top chemistry analyzers.


1975 ◽  
Vol 21 (1) ◽  
pp. 151-154
Author(s):  
Louis Rosenfeld

Abstract Data are presented for an electronic device that automatically halves "off-scale" signal voltages on the "SMA Flex-6" System (Technicon). This extends the usefulness of the system by obviating the need for most repeat analyses on dilutions of specimens containing constituents in concentrations that exceed the limits of the pre-calibrated chart paper. Accurate results are obtained because the chemical reactions are shown to be linear up to nearly twice the maximum calibration on the recorder paper for the following analytes: bilirubin, total and direct (20.0 mg/dl); alkaline phosphatase (700 U/ liter); lactate dehydrogenase (1200 U/liter); creatine kinase (2400 U/liter); and aspartate aminotransferase (600 U/liter). In contrast, dilution of sera 2-, 5-, and 10-fold with sodium chloride solution (8.5 g/liter) produces positive errors ranging from 6 to 38% for these enzymes, but has no significant effect on bilirubin.


Our Nature ◽  
1970 ◽  
Vol 3 (1) ◽  
pp. 20-25 ◽  
Author(s):  
H. Bhattacharya ◽  
L. Lun ◽  
G.D. Gomez R.

Biochemical changes in the liver, kidneys and gills of rosy barbs due to toxicity of CCl4 were measured after 96 hour exposure. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), blood urea nitrogen (BUN) and creatinin (CRN), levels were measured. Significant increase in ALP, ALT, LDH and BUN activities were observed in the liver in the treated groups compared to controls (P < 0.05). AST level was significantly higher in the kidneys. This study indicates that the enzymatic activity was comparatively higher in the liver than kidneys or gills, suggesting that the liver is the target organ of CCL4 toxicity to rosy barbs.Keywords: Toxicity, Rosy Barb, CCl4doi:10.3126/on.v3i1.330Our Nature (2005)5:20-25


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